v0.0.16 - Implement deny-by-default approval model with on-demand nostr_index derivation and --preapprove CLI flag

.dockerignore

@@ -0,0 +1,6 @@
+build/
+.git/
+*.o
+/*.a
+!resources/
+!resources/**

.gitignore

@@ -4,3 +4,6 @@ build/
 *.tar.gz
 .gitea_token
 resources/
+.test_mnemonic
+Trash/
+

.roo/commands/push.md

@@ -0,0 +1,7 @@
+---
+description: "Brief description of what this command does"
+---
+
+Run increment_and_push.sh, and supply a good git commit message. For example:
+
+./increment_and_push.sh "Fixed the bug with nip05 implementation"

.roo/commands/push_release.md

@@ -0,0 +1,7 @@
+---
+description: "This increments our git tag and version number, along with compiling and uploading a new release to our gitea page."
+---
+
+Run increment_and_push.sh -r -p, and supply a good git commit message. For example:
+
+./increment_and_push.sh "Fixed the bug with nip05 implementation"

Dockerfile.alpine-musl

@@ -1,77 +1,93 @@
 # Alpine-based MUSL static binary builder for nsigner
-# Produces portable binaries with zero runtime dependencies
-
-ARG DEBUG_BUILD=false
 
 FROM alpine:3.19 AS builder
 
-ARG DEBUG_BUILD=false
-
 RUN apk add --no-cache \
     build-base \
-    musl-dev \
+    linux-headers \
+    openssl-dev \
+    openssl-libs-static \
+    curl-dev \
+    curl-static \
+    zlib-static \
+    sqlite-dev \
+    sqlite-static \
+    brotli-static \
+    c-ares-static \
+    nghttp2-static \
+    libidn2-static \
+    libpsl-static \
+    libunistring-static \
+    zstd-static \
     git \
-    cmake \
-    pkgconfig \
     autoconf \
     automake \
     libtool \
-    openssl-dev \
-    openssl-libs-static \
-    zlib-dev \
-    zlib-static \
-    curl-dev \
-    curl-static \
-    linux-headers \
-    wget \
+    pkgconfig \
     bash
 
 WORKDIR /build
 
-# Build libsecp256k1 static for nostr_core_lib
+# Build libsecp256k1 from source with schnorr support
 RUN cd /tmp && \
-    git clone https://github.com/bitcoin-core/secp256k1.git && \
+    git clone --depth 1 https://github.com/bitcoin-core/secp256k1.git && \
     cd secp256k1 && \
     ./autogen.sh && \
-    ./configure --enable-static --disable-shared --prefix=/usr CFLAGS="-fPIC" && \
-    make -j$(nproc) && \
+    ./configure \
+      --prefix=/usr \
+      --enable-static \
+      --disable-shared \
+      --enable-module-schnorrsig \
+      --enable-module-extrakeys \
+      --enable-module-recovery && \
+    make -j"$(nproc)" && \
     make install && \
     rm -rf /tmp/secp256k1
 
-# Copy and build nostr_core_lib with signer-focused NIPs
-COPY nostr_core_lib /build/nostr_core_lib/
-RUN cd nostr_core_lib && \
-    chmod +x build.sh && \
-    sed -i 's/CFLAGS="-Wall -Wextra -std=c99 -fPIC -O2"/CFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0 -Wall -Wextra -std=c99 -fPIC -O2"/' build.sh && \
-    rm -f *.o *.a 2>/dev/null || true && \
-    ./build.sh --nips=1,6,13,17,19,44,46,59
+# Copy and build nostr_core_lib from project resources
+COPY resources/nostr_core_lib /build/nostr_core_lib/
+RUN if [ "$(uname -m)" = "aarch64" ] && ! command -v aarch64-linux-gnu-gcc >/dev/null 2>&1; then \
+      ln -s "$(command -v gcc)" /usr/local/bin/aarch64-linux-gnu-gcc; \
+    fi && \
+    cd /build/nostr_core_lib && \
+    chmod +x ./build.sh && \
+    ./build.sh --nips=1,4,6,19,44
 
-# Copy project source
+# Copy source files
 COPY src/ /build/src/
 
-# Build nsigner static binary
-RUN if [ "$DEBUG_BUILD" = "true" ]; then \
-        CFLAGS="-g -O2 -DDEBUG -fno-omit-frame-pointer"; \
-        STRIP_CMD="echo 'Keeping debug symbols'"; \
-        echo "Building debug binary"; \
-    else \
-        CFLAGS="-O2"; \
-        STRIP_CMD="strip /build/nsigner_static"; \
-        echo "Building production binary"; \
-    fi && \
-    gcc -static $CFLAGS -Wall -Wextra -std=c99 \
-    -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0 \
-    -Isrc \
-    src/main.c \
-    -o /build/nsigner_static && \
-    eval "$STRIP_CMD"
+# Build nsigner as a fully static binary
+RUN ARCH="$(uname -m)"; \
+    case "$ARCH" in \
+      aarch64|arm64) NOSTR_LIB="/build/nostr_core_lib/libnostr_core_arm64.a" ;; \
+      x86_64|amd64)  NOSTR_LIB="/build/nostr_core_lib/libnostr_core_x64.a" ;; \
+      *) echo "Unsupported build arch: $ARCH"; exit 1 ;; \
+    esac; \
+    [ -f "$NOSTR_LIB" ] || { echo "Missing nostr core lib: $NOSTR_LIB"; ls -la /build/nostr_core_lib; exit 1; }; \
+    gcc -static -Os -ffunction-sections -fdata-sections -Wl,--gc-sections -s -Wall -Wextra -std=c99 \
+      -I/build/nostr_core_lib \
+      -I/build/nostr_core_lib/nostr_core \
+      -I/build/nostr_core_lib/cjson \
+      /build/src/main.c \
+      /build/src/secure_mem.c \
+      /build/src/mnemonic.c \
+      /build/src/role_table.c \
+      /build/src/selector.c \
+      /build/src/enforcement.c \
+      /build/src/dispatcher.c \
+      /build/src/policy.c \
+      /build/src/server.c \
+      /build/src/transport_frame.c \
+      /build/src/key_store.c \
+      /build/src/socket_name.c \
+      "$NOSTR_LIB" \
+      -o /build/nsigner_static \
+      $(pkg-config --static --libs libcurl openssl) \
+      -lsecp256k1 -lsqlite3 -lz -lpthread -lm
 
-RUN echo "=== Binary Information ===" && \
-    file /build/nsigner_static && \
-    ls -lh /build/nsigner_static && \
-    echo "=== Checking for dynamic dependencies ===" && \
-    (ldd /build/nsigner_static 2>&1 || echo "Binary is static") && \
-    echo "=== Build complete ==="
+RUN strip /build/nsigner_static || true
+RUN file /build/nsigner_static && \
+    (ldd /build/nsigner_static 2>&1 || true)
 
 FROM scratch AS output
 COPY --from=builder /build/nsigner_static /nsigner_static

Makefile

@@ -1,6 +1,6 @@
 CC := gcc
-CFLAGS := -Wall -Wextra -std=c99 -O2 -Isrc -Isrc/cjson
-LDFLAGS :=
+CFLAGS := -Wall -Wextra -std=c99 -Os -ffunction-sections -fdata-sections -Isrc -Iresources/nostr_core_lib -Iresources/nostr_core_lib/nostr_core -Iresources/nostr_core_lib/cjson
+LDFLAGS := -Wl,--gc-sections resources/nostr_core_lib/libnostr_core_x64.a -lz -ldl -lpthread -lm -lssl -lcrypto -lcurl -lsecp256k1
 
 SRC_DIR := src
 BUILD_DIR := build
@@ -18,19 +18,12 @@ SOURCES := \
 	$(SRC_DIR)/dispatcher.c \
 	$(SRC_DIR)/policy.c \
 	$(SRC_DIR)/server.c \
-	$(SRC_DIR)/cjson/cJSON.c
+	$(SRC_DIR)/transport_frame.c \
+	$(SRC_DIR)/key_store.c \
+	$(SRC_DIR)/socket_name.c
+
+HEADERS :=
 
-HEADERS := \
-	$(SRC_DIR)/main.h \
-	$(SRC_DIR)/secure_mem.h \
-	$(SRC_DIR)/mnemonic.h \
-	$(SRC_DIR)/role_table.h \
-	$(SRC_DIR)/selector.h \
-	$(SRC_DIR)/enforcement.h \
-	$(SRC_DIR)/dispatcher.h \
-	$(SRC_DIR)/policy.h \
-	$(SRC_DIR)/server.h \
-	$(SRC_DIR)/cjson/cJSON.h
 
 TEST_MNEMONIC_TARGET := $(BUILD_DIR)/test_mnemonic
 TEST_ROLE_TARGET := $(BUILD_DIR)/test_role_table
@@ -39,14 +32,18 @@ TEST_ENFORCEMENT_TARGET := $(BUILD_DIR)/test_enforcement
 TEST_DISPATCHER_TARGET := $(BUILD_DIR)/test_dispatcher
 TEST_POLICY_TARGET := $(BUILD_DIR)/test_policy
 TEST_INTEGRATION_TARGET := $(BUILD_DIR)/test_integration
+TEST_SOCKET_NAME_TARGET := $(BUILD_DIR)/test_socket_name
 
-.PHONY: all dev static static-debug static-arm64 test test-integration test-mnemonic test-role test-selector test-enforcement test-dispatcher test-policy clean
+.PHONY: all lib dev static static-debug static-arm64 test test-integration test-mnemonic test-role test-selector test-enforcement test-dispatcher test-policy test-socket-name clean
 
 all: dev
 
-dev: $(TARGET_DEV)
+lib:
+	cd resources/nostr_core_lib && ./build.sh --nips=1,4,6,19,44
 
-$(TARGET_DEV): $(SOURCES) $(HEADERS)
+dev: lib $(TARGET_DEV)
+
+$(TARGET_DEV): $(SOURCES)
 	@mkdir -p $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(SOURCES) -o $(TARGET_DEV) $(LDFLAGS)
 
@@ -62,7 +59,7 @@ static-arm64:
 	chmod +x ./build_static.sh
 	./build_static.sh --arch arm64
 
-test: test-mnemonic test-role test-selector test-enforcement test-dispatcher test-policy
+test: lib test-mnemonic test-role test-selector test-enforcement test-dispatcher test-policy test-socket-name
 
 test-integration: $(TEST_INTEGRATION_TARGET) $(TARGET_DEV)
 	./$(TEST_INTEGRATION_TARGET)
@@ -85,27 +82,30 @@ test-dispatcher: $(TEST_DISPATCHER_TARGET)
 test-policy: $(TEST_POLICY_TARGET)
 	./$(TEST_POLICY_TARGET)
 
-$(TEST_MNEMONIC_TARGET): $(TEST_DIR)/test_mnemonic.c $(SRC_DIR)/mnemonic.c $(SRC_DIR)/secure_mem.c $(SRC_DIR)/mnemonic.h $(SRC_DIR)/secure_mem.h
+test-socket-name: $(TEST_SOCKET_NAME_TARGET)
+	./$(TEST_SOCKET_NAME_TARGET)
+
+$(TEST_MNEMONIC_TARGET): $(TEST_DIR)/test_mnemonic.c $(SRC_DIR)/mnemonic.c $(SRC_DIR)/secure_mem.c
 	@mkdir -p $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(TEST_DIR)/test_mnemonic.c $(SRC_DIR)/mnemonic.c $(SRC_DIR)/secure_mem.c -o $(TEST_MNEMONIC_TARGET) $(LDFLAGS)
 
-$(TEST_ROLE_TARGET): $(TEST_DIR)/test_role_table.c $(SRC_DIR)/role_table.c $(SRC_DIR)/role_table.h
+$(TEST_ROLE_TARGET): $(TEST_DIR)/test_role_table.c $(SRC_DIR)/role_table.c
 	@mkdir -p $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(TEST_DIR)/test_role_table.c $(SRC_DIR)/role_table.c -o $(TEST_ROLE_TARGET) $(LDFLAGS)
 
-$(TEST_SELECTOR_TARGET): $(TEST_DIR)/test_selector.c $(SRC_DIR)/selector.c $(SRC_DIR)/role_table.c $(SRC_DIR)/selector.h $(SRC_DIR)/role_table.h
+$(TEST_SELECTOR_TARGET): $(TEST_DIR)/test_selector.c $(SRC_DIR)/selector.c $(SRC_DIR)/role_table.c
 	@mkdir -p $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(TEST_DIR)/test_selector.c $(SRC_DIR)/selector.c $(SRC_DIR)/role_table.c -o $(TEST_SELECTOR_TARGET) $(LDFLAGS)
 
-$(TEST_ENFORCEMENT_TARGET): $(TEST_DIR)/test_enforcement.c $(SRC_DIR)/enforcement.c $(SRC_DIR)/role_table.c $(SRC_DIR)/enforcement.h $(SRC_DIR)/role_table.h
+$(TEST_ENFORCEMENT_TARGET): $(TEST_DIR)/test_enforcement.c $(SRC_DIR)/enforcement.c $(SRC_DIR)/role_table.c
 	@mkdir -p $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(TEST_DIR)/test_enforcement.c $(SRC_DIR)/enforcement.c $(SRC_DIR)/role_table.c -o $(TEST_ENFORCEMENT_TARGET) $(LDFLAGS)
 
-$(TEST_DISPATCHER_TARGET): $(TEST_DIR)/test_dispatcher.c $(SRC_DIR)/dispatcher.c $(SRC_DIR)/selector.c $(SRC_DIR)/enforcement.c $(SRC_DIR)/role_table.c $(SRC_DIR)/mnemonic.c $(SRC_DIR)/secure_mem.c $(SRC_DIR)/cjson/cJSON.c $(SRC_DIR)/dispatcher.h $(SRC_DIR)/selector.h $(SRC_DIR)/enforcement.h $(SRC_DIR)/role_table.h $(SRC_DIR)/mnemonic.h $(SRC_DIR)/secure_mem.h $(SRC_DIR)/cjson/cJSON.h
+$(TEST_DISPATCHER_TARGET): $(TEST_DIR)/test_dispatcher.c $(SRC_DIR)/dispatcher.c $(SRC_DIR)/key_store.c $(SRC_DIR)/selector.c $(SRC_DIR)/enforcement.c $(SRC_DIR)/role_table.c $(SRC_DIR)/mnemonic.c $(SRC_DIR)/secure_mem.c
 	@mkdir -p $(BUILD_DIR)
-	$(CC) $(CFLAGS) $(TEST_DIR)/test_dispatcher.c $(SRC_DIR)/dispatcher.c $(SRC_DIR)/selector.c $(SRC_DIR)/enforcement.c $(SRC_DIR)/role_table.c $(SRC_DIR)/mnemonic.c $(SRC_DIR)/secure_mem.c $(SRC_DIR)/cjson/cJSON.c -o $(TEST_DISPATCHER_TARGET) $(LDFLAGS)
+	$(CC) $(CFLAGS) $(TEST_DIR)/test_dispatcher.c $(SRC_DIR)/dispatcher.c $(SRC_DIR)/key_store.c $(SRC_DIR)/selector.c $(SRC_DIR)/enforcement.c $(SRC_DIR)/role_table.c $(SRC_DIR)/mnemonic.c $(SRC_DIR)/secure_mem.c -o $(TEST_DISPATCHER_TARGET) $(LDFLAGS)
 
-$(TEST_POLICY_TARGET): $(TEST_DIR)/test_policy.c $(SRC_DIR)/policy.c $(SRC_DIR)/policy.h $(SRC_DIR)/role_table.h
+$(TEST_POLICY_TARGET): $(TEST_DIR)/test_policy.c $(SRC_DIR)/policy.c
 	@mkdir -p $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(TEST_DIR)/test_policy.c $(SRC_DIR)/policy.c -o $(TEST_POLICY_TARGET) $(LDFLAGS)
 
@@ -113,5 +113,9 @@ $(TEST_INTEGRATION_TARGET): $(TEST_DIR)/test_integration.c
 	@mkdir -p $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(TEST_DIR)/test_integration.c -o $(TEST_INTEGRATION_TARGET) $(LDFLAGS)
 
+$(TEST_SOCKET_NAME_TARGET): $(TEST_DIR)/test_socket_name.c $(SRC_DIR)/socket_name.c
+	@mkdir -p $(BUILD_DIR)
+	$(CC) $(CFLAGS) $(TEST_DIR)/test_socket_name.c $(SRC_DIR)/socket_name.c -o $(TEST_SOCKET_NAME_TARGET) $(LDFLAGS)
+
 clean:
 	rm -rf $(BUILD_DIR)

README.md

@@ -70,13 +70,15 @@ This reduces deployment variability and shrinks the runtime trust surface.
 
 When started, `n_signer` immediately enters terminal input mode:
 
-1. Prompt for mnemonic (terminal echo disabled).
-2. Parse and validate mnemonic.
-3. Build in-memory role/selector state.
-4. Initialize transport endpoints.
-5. Switch to running status display.
+1. Choose mnemonic source: `[E]nter existing mnemonic` (default) or `[G]enerate new mnemonic`.
+   - On `E`: prompt for mnemonic with terminal echo disabled, then validate.
+   - On `G`: generate a fresh 12-word BIP-39 mnemonic from `getrandom(2)`, display it numbered with a "WRITE THIS DOWN — IT WILL NOT BE SHOWN AGAIN" warning, then continue. There is no confirmation step.
+2. Build in-memory role/selector state from the mnemonic.
+3. Pick the abstract socket name (random BIP-39 pair, or `--socket-name` / `--name` / `-n` override).
+4. Initialize transport endpoints and bind the socket.
+5. Switch to running status display, with the signer name and socket address shown in the banner.
 
-No startup files are read or written.
+No startup files are read or written. The mnemonic — typed or generated — lives only in `mlock`'d memory and is zeroized on shutdown or crash.
 
 ### 3.2 Running phase (status display + signer)
 
@@ -106,9 +108,9 @@ Activity (latest first)
 
 Hotkeys
 -------
-a  add role
+a  toggle auto-approve(prompt) for this session
 r  refresh
-l  lock session
+l  lock/reunlock session
 q  quit
 ```
 
@@ -125,7 +127,7 @@ method: sign_event
 selector: role=ops
 purpose/curve: nostr/secp256k1
 
-[y] allow once    [n] deny    [a] always allow for this session
+[y] allow once    [n] deny    [a] always allow this session
 ```
 
 No response is emitted to caller until the local user decides.
@@ -171,6 +173,13 @@ Request shape is JSON-RPC with NIP-46-style methods and optional trailing select
 { "id": "4", "method": "sign_event", "params": ["<event_json>", { "role_path": "m/84'/0'/0'/0/5", "purpose": "bitcoin", "curve": "secp256k1" }] }
 ```
 
+Implemented signer verbs in this build:
+
+- `get_public_key`
+- `sign_event`
+- `nip04_encrypt` / `nip04_decrypt`
+- `nip44_encrypt` / `nip44_decrypt`
+
 Selector resolution order:
 
 1. `role`
@@ -207,7 +216,9 @@ This prevents cross-protocol misuse inside one mnemonic-rooted signer process.
 
 ### 7.1 Linux desktop: abstract namespace Unix socket
 
-Primary local transport is AF_UNIX abstract namespace (for example `@nsigner`).
+Primary local transport is AF_UNIX abstract namespace.
+
+Each running `nsigner` process binds to a unique abstract name of the form `@nsigner_<word1>_<word2>`, where the two words are picked at random from the BIP-39 English wordlist at startup (e.g. `@nsigner_hairy_dog`). This lets multiple signers coexist on one host.
 
 Properties:
 
@@ -215,6 +226,20 @@ Properties:
 - endpoint lifetime bound to process/kernel namespace
 - no stale socket files
 - caller identity via peer credentials (`SO_PEERCRED`)
+- per-launch random name avoids collisions between concurrent instances and leaks no seed-derived identifier
+
+Naming rules:
+
+- Default: random pick at startup, displayed in the TUI banner.
+- Override: `--socket-name <name>` (alias: `--name <name>` / `-n <name>`) forces a specific name (useful for scripts and tests).
+- Collision: if the chosen random name is already bound by another process, `nsigner` retries with a fresh pair up to 8 times before erroring out with a hint to use an explicit name override.
+
+Discovery:
+
+- `nsigner list` enumerates currently bound `nsigner_*` abstract sockets by reading `/proc/net/unix`.
+- `nsigner --listen stdio` runs one framed JSON-RPC request/response over stdin/stdout.
+- `nsigner --listen qrexec` is the same stdio framing mode, but caller identity can be derived from `QREXEC_REMOTE_DOMAIN` (displayed as `qubes:<source-vm>`).
+- `nsigner --listen tcp:IPv4:PORT` or `tcp:[IPv6]:PORT` enables TCP listening for non-AF_UNIX clients (for example `tcp:127.0.0.1:8080`, `tcp:[::]:8080`, or `tcp:[fd00::1234]:8080`).
 
 ### 7.2 ESP32 MCU: USB-CDC serial
 
@@ -258,23 +283,62 @@ Qubes deployment runs `n_signer` in a dedicated signer qube as a foreground proc
 nsigner
 ```
 
-Program starts in attached foreground mode and prompts for mnemonic.
+Program starts in attached foreground mode and prompts for mnemonic. After mnemonic acceptance, the TUI banner shows the randomly assigned signer name and its abstract socket address.
+
+To force a specific socket name (e.g. for scripted clients):
+
+```bash
+nsigner --name my_test_signer
+```
+
+Qubes/qrexec service mode (single framed request over stdin/stdout):
+
+```bash
+nsigner --listen qrexec
+```
+
+Generic stdio transport mode (single framed request over stdin/stdout):
+
+```bash
+nsigner --listen stdio
+```
+
+TCP transport mode (no TUI; serves requests until terminated):
+
+```bash
+nsigner --listen tcp:[::]:8080
+```
 
 ### 9.2 Send a request (client mode)
 
-From another terminal:
+From another terminal, target the signer by its socket name:
 
 ```bash
-nsigner client '{"id":"1","method":"get_public_key","params":[]}'
+nsigner --socket-name nsigner_hairy_dog client '{"id":"1","method":"get_public_key","params":[]}'
 ```
 
+If only one signer is running you can omit the override and the client will use the default discovery rule.
+
 Example signing request:
 
 ```bash
-nsigner client '{"id":"2","method":"sign_event","params":["<event_json>",{"role":"main"}]}'
+nsigner -n nsigner_hairy_dog client '{"id":"2","method":"sign_event","params":["<event_json>",{"role":"main"}]}'
 ```
 
-### 9.3 Example session
+### 9.3 List running signers
+
+```bash
+nsigner list
+```
+
+Prints the abstract socket names of any currently running `nsigner` instances, e.g.:
+
+```text
+@nsigner_hairy_dog
+@nsigner_brave_canyon
+```
+
+### 9.4 Example session
 
 Terminal A:
 
@@ -282,14 +346,16 @@ Terminal A:
 $ nsigner
 [unlock] enter mnemonic:
 [ok] session unlocked
-[listen] unix-abstract:@nsigner
+  signer name : hairy dog
+  socket      : @nsigner_hairy_dog
+[listen] unix-abstract:@nsigner_hairy_dog
 [prompt] caller=uid:1000 method=sign_event role=main -> allow? (y/n)
 ```
 
 Terminal B:
 
 ```text
-$ nsigner client '{"id":"2","method":"sign_event","params":["<event_json>",{"role":"main"}]}'
+$ nsigner --socket-name nsigner_hairy_dog client '{"id":"2","method":"sign_event","params":["<event_json>",{"role":"main"}]}'
 {"id":"2","result":"<signed_event_json>"}
 ```
 
@@ -301,13 +367,13 @@ Build outputs a single executable artifact.
 - [`Makefile`](Makefile): local build targets
 - [`Dockerfile.alpine-musl`](Dockerfile.alpine-musl): reproducible Alpine musl toolchain
 - [`increment_and_push.sh`](increment_and_push.sh): version/tag/release workflow
-- [`src/main.h`](src/main.h): version macros
+- [`src/main.c`](src/main.c): version macros (`NSIGNER_VERSION*`)
 
 Local dev build:
 
 ```bash
 make dev
-./build/nsigner_dev --version
+./build/nsigner --version
 ```
 
 Static build:
@@ -320,6 +386,9 @@ Static build:
 ## 11. Document map
 
 - [`README.md`](README.md): authoritative behavior specification for the foreground single-program model
+- [`documents/CLIENT_IMPLEMENTATION.md`](documents/CLIENT_IMPLEMENTATION.md): client integration contract and framing behavior
+- [`documents/QUBES_OS.md`](documents/QUBES_OS.md): Qubes OS deployment/integration checklist for dedicated signer qubes
+- [`documents/FIPS_DEPLOYMENT.md`](documents/FIPS_DEPLOYMENT.md): Tier-1 FIPS deployment runbook using loopback TCP listener
 - [`plans/nsigner.md`](plans/nsigner.md): implementation plan and sequencing
 - [`plans/seed_phrase_uses.md`](plans/seed_phrase_uses.md): seed phrase domain/use catalog and caveats
 - [`firmware/README.md`](firmware/README.md): firmware-side notes for MCU transport/UI integration

build_static.sh

@@ -1,35 +1,30 @@
 #!/bin/bash
 
-# Build fully static MUSL binaries for nsigner using Alpine Docker
+# Build fully static MUSL binary for nsigner using Alpine Docker
 
-set -e
+set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 BUILD_DIR="$SCRIPT_DIR/build"
 DOCKERFILE="$SCRIPT_DIR/Dockerfile.alpine-musl"
 
-DEBUG_BUILD=false
 TARGET_ARCH=""
 
 while [[ $# -gt 0 ]]; do
     case "$1" in
-        --debug)
-            DEBUG_BUILD=true
-            shift
-            ;;
         --arch)
-            if [[ -z "$2" ]]; then
+            if [[ -z "${2:-}" ]]; then
                 echo "ERROR: --arch requires a value"
-                echo "Usage: $0 [--debug] [--arch <arm64|armv7|x86_64>]"
+                echo "Usage: $0 [--arch <x86_64|arm64|armv7>]"
                 exit 1
             fi
             case "$2" in
-                arm64|armv7|x86_64)
+                x86_64|arm64|armv7)
                     TARGET_ARCH="$2"
                     ;;
                 *)
                     echo "ERROR: Unsupported architecture '$2'"
-                    echo "Supported values: arm64, armv7, x86_64"
+                    echo "Supported values: x86_64, arm64, armv7"
                     exit 1
                     ;;
             esac
@@ -37,48 +32,24 @@ while [[ $# -gt 0 ]]; do
             ;;
         *)
             echo "ERROR: Unknown argument '$1'"
-            echo "Usage: $0 [--debug] [--arch <arm64|armv7|x86_64>]"
+            echo "Usage: $0 [--arch <x86_64|arm64|armv7>]"
             exit 1
             ;;
     esac
 done
 
-if [ "$DEBUG_BUILD" = true ]; then
-    echo "=========================================="
-    echo "nsigner MUSL Static Binary Builder (DEBUG MODE)"
-    echo "=========================================="
-else
-    echo "=========================================="
-    echo "nsigner MUSL Static Binary Builder (PRODUCTION MODE)"
-    echo "=========================================="
-fi
-echo "Project directory: $SCRIPT_DIR"
-echo "Build directory: $BUILD_DIR"
-echo "Debug build: $DEBUG_BUILD"
-if [[ -n "$TARGET_ARCH" ]]; then
-    echo "Requested target architecture: $TARGET_ARCH"
-fi
-echo ""
-
-mkdir -p "$BUILD_DIR"
-
-if ! command -v docker &> /dev/null; then
+if ! command -v docker >/dev/null 2>&1; then
     echo "ERROR: Docker is not installed or not in PATH"
     exit 1
 fi
 
-if ! docker info &> /dev/null; then
-    echo "ERROR: Docker daemon is not running or user not in docker group"
+if ! docker info >/dev/null 2>&1; then
+    echo "ERROR: Docker daemon is not running or user lacks permissions"
     exit 1
 fi
 
-DOCKER_CMD="docker"
-
-echo "✓ Docker is available and running"
-echo ""
-
-ARCH=$(uname -m)
-case "$ARCH" in
+HOST_UNAME="$(uname -m)"
+case "$HOST_UNAME" in
     x86_64)
         HOST_ARCH="x86_64"
         ;;
@@ -89,147 +60,92 @@ case "$ARCH" in
         HOST_ARCH="armv7"
         ;;
     *)
-        HOST_ARCH="unknown"
+        HOST_ARCH="x86_64"
         ;;
 esac
 
-if [[ -n "$TARGET_ARCH" ]]; then
-    ARCH="$TARGET_ARCH"
-fi
+ARCH="${TARGET_ARCH:-$HOST_ARCH}"
 
 case "$ARCH" in
     x86_64)
         PLATFORM="linux/amd64"
         OUTPUT_NAME="nsigner_static_x86_64"
         ;;
-    aarch64|arm64)
-        ARCH="arm64"
+    arm64)
         PLATFORM="linux/arm64"
         OUTPUT_NAME="nsigner_static_arm64"
         ;;
-    armv7l|armv7)
-        ARCH="armv7"
+    armv7)
         PLATFORM="linux/arm/v7"
         OUTPUT_NAME="nsigner_static_armv7"
         ;;
     *)
-        echo "WARNING: Unknown architecture: $ARCH"
-        echo "Defaulting to linux/amd64"
-        PLATFORM="linux/amd64"
-        OUTPUT_NAME="nsigner_static_${ARCH}"
+        echo "ERROR: Unsupported target architecture '$ARCH'"
+        exit 1
         ;;
 esac
 
-if [[ "$HOST_ARCH" != "unknown" && "$ARCH" != "$HOST_ARCH" ]]; then
-    echo "NOTE: Cross-building from host '$HOST_ARCH' to target '$ARCH'."
-    if ! docker buildx version >/dev/null 2>&1; then
-        echo "ERROR: docker buildx is required for cross-architecture builds but is not available."
+mkdir -p "$BUILD_DIR"
+
+IMAGE_TAG="nsigner-static-builder:${ARCH}"
+CONTAINER_NAME=""
+cleanup() {
+    if [[ -n "$CONTAINER_NAME" ]]; then
+        docker rm -f "$CONTAINER_NAME" >/dev/null 2>&1 || true
+    fi
+}
+trap cleanup EXIT
+
+echo "=========================================="
+echo "nsigner static build"
+echo "=========================================="
+echo "Project root: $SCRIPT_DIR"
+echo "Dockerfile:   $DOCKERFILE"
+echo "Platform:     $PLATFORM"
+echo "Output:       $BUILD_DIR/$OUTPUT_NAME"
+echo ""
+
+if [ "$ARCH" != "$HOST_ARCH" ]; then
+    echo "[0/3] Preparing buildx + QEMU for cross-architecture build"
+    if ! docker buildx inspect >/dev/null 2>&1; then
+        echo "ERROR: docker buildx is not available"
         exit 1
     fi
-    echo "✓ docker buildx is available for cross-architecture build"
-    echo ""
+    docker run --privileged --rm tonistiigi/binfmt --install all >/dev/null
+
+    if ! docker buildx inspect nsigner-builder >/dev/null 2>&1; then
+        docker buildx create --name nsigner-builder --driver docker-container --use >/dev/null
+    else
+        docker buildx use nsigner-builder >/dev/null
+    fi
+    docker buildx inspect --bootstrap >/dev/null
 fi
 
-if [ "$DEBUG_BUILD" = true ]; then
-    OUTPUT_NAME="${OUTPUT_NAME}_debug"
-fi
-
-echo "Building for platform: $PLATFORM"
-echo "Output binary: $OUTPUT_NAME"
-echo ""
-
-echo "=========================================="
-echo "Step 1: Building Alpine Docker image"
-echo "=========================================="
-
-$DOCKER_CMD build \
+echo "[1/3] Building builder stage from project root context"
+docker buildx build \
     --platform "$PLATFORM" \
-    --build-arg DEBUG_BUILD=$DEBUG_BUILD \
-    -f "$DOCKERFILE" \
-    -t nsigner-musl-builder:latest \
-    --progress=plain \
-    .
-
-echo ""
-echo "✓ Docker image built successfully"
-echo ""
-
-echo "=========================================="
-echo "Step 2: Extracting static binary"
-echo "=========================================="
-
-$DOCKER_CMD build \
-    --platform "$PLATFORM" \
-    --build-arg DEBUG_BUILD=$DEBUG_BUILD \
     --target builder \
     -f "$DOCKERFILE" \
-    -t nsigner-static-builder-stage:latest \
-    . > /dev/null 2>&1
-
-CONTAINER_ID=$($DOCKER_CMD create nsigner-static-builder-stage:latest)
-$DOCKER_CMD cp "$CONTAINER_ID:/build/nsigner_static" "$BUILD_DIR/$OUTPUT_NAME"
-$DOCKER_CMD rm "$CONTAINER_ID" > /dev/null
+    -t "$IMAGE_TAG" \
+    --load \
+    "$SCRIPT_DIR"
 
+echo "[2/3] Extracting static binary"
+CONTAINER_NAME="$(docker create "$IMAGE_TAG")"
+docker cp "$CONTAINER_NAME:/build/nsigner_static" "$BUILD_DIR/$OUTPUT_NAME"
 chmod +x "$BUILD_DIR/$OUTPUT_NAME"
+strip "$BUILD_DIR/$OUTPUT_NAME" >/dev/null 2>&1 || true
 
-echo "✓ Binary extracted to: $BUILD_DIR/$OUTPUT_NAME"
-echo ""
+echo "[3/3] Verifying static binary"
+file "$BUILD_DIR/$OUTPUT_NAME"
 
-echo "=========================================="
-echo "Step 3: Verifying static binary"
-echo "=========================================="
-echo ""
-
-if LDD_OUTPUT=$(timeout 5 ldd "$BUILD_DIR/$OUTPUT_NAME" 2>&1); then
-    if echo "$LDD_OUTPUT" | grep -q "not a dynamic executable"; then
-        echo "✓ Binary is fully static"
-        TRULY_STATIC=true
-    elif echo "$LDD_OUTPUT" | grep -q "statically linked"; then
-        echo "✓ Binary is statically linked"
-        TRULY_STATIC=true
-    else
-        echo "⚠ WARNING: Binary may have dynamic dependencies:"
-        echo "$LDD_OUTPUT"
-        TRULY_STATIC=false
-    fi
+LDD_OUTPUT="$(ldd "$BUILD_DIR/$OUTPUT_NAME" 2>&1 || true)"
+echo "$LDD_OUTPUT"
+if echo "$LDD_OUTPUT" | grep -Eq "not a dynamic executable|statically linked"; then
+    echo "Static check: PASS"
 else
-    if file "$BUILD_DIR/$OUTPUT_NAME" | grep -q "statically linked"; then
-        echo "✓ Binary is statically linked (verified with file command)"
-        TRULY_STATIC=true
-    else
-        echo "⚠ Could not verify static linking (ldd check failed)"
-        TRULY_STATIC=false
-    fi
+    echo "Static check: WARNING (verify manually)"
 fi
 
 echo ""
-echo "File size: $(ls -lh "$BUILD_DIR/$OUTPUT_NAME" | awk '{print $5}')"
-echo ""
-
-echo "Testing binary execution:"
-if "$BUILD_DIR/$OUTPUT_NAME" --version 2>&1 | head -5; then
-    echo "✓ Binary executes successfully"
-else
-    echo "⚠ Binary execution test failed"
-fi
-
-echo ""
-echo "=========================================="
-echo "Build Summary"
-echo "=========================================="
-echo "Binary: $BUILD_DIR/$OUTPUT_NAME"
-echo "Size: $(du -h "$BUILD_DIR/$OUTPUT_NAME" | cut -f1)"
-echo "Platform: $PLATFORM"
-if [ "$DEBUG_BUILD" = true ]; then
-    echo "Build Type: DEBUG"
-else
-    echo "Build Type: PRODUCTION"
-fi
-if [ "$TRULY_STATIC" = true ]; then
-    echo "Linkage: Fully static binary"
-else
-    echo "Linkage: Static binary (verification inconclusive)"
-fi
-
-echo ""
-echo "✓ Build complete!"
+echo "Build complete: $BUILD_DIR/$OUTPUT_NAME"

documents/CLIENT_IMPLEMENTATION.md

@@ -0,0 +1,458 @@
+# CLIENT_IMPLEMENTATION.md
+
+## 1. Purpose
+
+This document is the client-integration spec for `nsigner`.
+
+It is written for agent/tool authors implementing robust request flows against the local signer process.
+
+---
+
+## 2. Discovery and socket targeting
+
+`nsigner` currently supports two transport families:
+
+- Linux AF_UNIX **abstract namespace** sockets.
+- Stdio framed mode (`--listen stdio` and `--listen qrexec`) for one request/response exchange.
+
+For AF_UNIX:
+
+- Socket names are exposed in `/proc/net/unix` with a leading `@`.
+- Typical runtime names: `@nsigner_hairy_dog`, `@nsigner_brave_canyon`.
+- Clients pass the socket name **without** `@` to CLI flags (example: `nsigner_hairy_dog`).
+
+### 2.1 Discovery rules
+
+Use one of these patterns:
+
+1. Explicit target (recommended): pass `--socket-name` / `--name` / `-n`.
+2. Enumerate with `nsigner list` and select one.
+3. Auto-discovery only when exactly one signer is running.
+
+### 2.2 Enumerating running signers
+
+```bash
+nsigner list
+```
+
+Expected output format (one per line):
+
+```text
+@nsigner
+@nsigner_hairy_dog
+@nsigner_brave_canyon
+```
+
+Clients should accept both `@nsigner` and `@nsigner_*` names.
+
+### 2.3 Stdio / qrexec mode
+
+In server mode:
+
+- `nsigner --listen stdio`: reads exactly one framed request from stdin and writes one framed response to stdout.
+- `nsigner --listen qrexec`: same behavior, but caller identity may be tagged from `QREXEC_REMOTE_DOMAIN` as `qubes:<vm-name>`.
+
+This mode is server-side only in the current CLI (the `client` subcommand still targets AF_UNIX).
+
+---
+
+## 3. Transport framing
+
+Signer requests/responses use a length-prefixed frame format over the socket:
+
+- Prefix: 4-byte unsigned big-endian length `N`
+- Payload: `N` bytes UTF-8 JSON text
+- One JSON-RPC object per frame
+
+### 3.1 Framing pseudocode
+
+Write:
+
+1. Serialize JSON to bytes
+2. Compute `len(payload)`
+3. Send `uint32_be(length)` then payload bytes
+
+Read:
+
+1. Read exactly 4 bytes
+2. Parse big-endian payload length
+3. Read exactly `length` bytes
+4. Parse JSON
+
+Do not assume line-delimited JSON.
+
+---
+
+## 4. JSON-RPC contract
+
+### 4.1 Request shape
+
+```json
+{ "id": "1", "method": "get_public_key", "params": [] }
+```
+
+Methods are NIP-46 style verbs.
+
+### 4.2 Implemented methods
+
+- `get_public_key`
+- `sign_event`
+- `nip04_encrypt`
+- `nip04_decrypt`
+- `nip44_encrypt`
+- `nip44_decrypt`
+
+### 4.3 Selector options
+
+The last param may include selector options:
+
+- `role`
+- `nostr_index`
+- `role_path`
+
+Resolution order:
+
+1. `role`
+2. `nostr_index`
+3. `role_path`
+4. default role `main`
+
+Conflicting selector fields must be rejected as `ambiguous_role_selector`.
+
+### 4.4 Selector example
+
+```json
+{
+  "id": "2",
+  "method": "sign_event",
+  "params": [
+    "<event_json>",
+    { "role": "main" }
+  ]
+}
+```
+
+---
+
+## 5. Error handling contract
+
+Representative error names clients must handle:
+
+- `invalid_request`
+- `method_not_found`
+- `ambiguous_role_selector`
+- `unknown_role`
+- `purpose_mismatch`
+- `curve_mismatch`
+- `unauthorized`
+- `approval_denied`
+- `internal_error`
+
+### 5.1 Recovery guidance
+
+- `invalid_request`: client bug or malformed payload; fix request and retry.
+- `method_not_found`: version mismatch; feature-detect and downgrade behavior.
+- `ambiguous_role_selector`: send exactly one selector strategy.
+- `unknown_role`: selector did not resolve; verify role inventory/config.
+- `purpose_mismatch` / `curve_mismatch`: selected key is incompatible with method; pick compatible selector.
+- `unauthorized`: caller identity disallowed by policy; do not blind-retry.
+- `approval_denied`: user rejected prompt; treat as final unless user initiates retry.
+- `internal_error`: bounded retry with backoff; surface diagnostics.
+
+---
+
+## 6. Approval semantics
+
+Approval has two layers:
+
+1. Policy/identity checks (caller and method authorization)
+2. User prompt (interactive allow/deny)
+
+Important behavior:
+
+- Passing identity checks does **not** bypass prompts.
+- Non-interactive/no-TTY contexts can resolve to deny by policy/test configuration.
+- Clients must treat `approval_denied` as a normal, expected outcome.
+
+### 6.1 UX recommendation
+
+If a signing call is denied, return control to the user and let them explicitly retry.
+
+---
+
+## 7. Multi-instance, concurrency, and timeouts
+
+### 7.1 Multi-instance safety
+
+- Multiple signers can coexist using different socket names.
+- Always pin requests to a selected signer name once chosen.
+- Avoid “discover per request” after initial bind in long-running clients.
+
+### 7.2 Connection strategy
+
+- Keep one connection per in-flight request path, or serialize requests if your client runtime is simple.
+- Validate response `id` correlation before completing promise/future.
+
+### 7.3 Timeout guidance
+
+Use separate timeouts:
+
+- connect timeout (short)
+- write timeout (short)
+- read timeout (longer, because human approval may be required)
+
+For prompt-requiring methods, use a read timeout that accounts for user interaction.
+
+---
+
+## 8. Security expectations for clients
+
+- Treat socket access as sensitive local capability.
+- Do not log plaintext secrets, private keys, or full decrypted payloads.
+- Redact request params for encrypt/decrypt methods in normal logs.
+- Validate method-level expectations before sending (selector + purpose compatibility).
+- Use least-privilege execution context for any process that can reach the signer socket.
+
+---
+
+## 9. Reference code snippets
+
+## 9.1 C (frame write/read skeleton)
+
+```c
+#include <arpa/inet.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+static int write_all(int fd, const void *buf, size_t len) {
+    const unsigned char *p = (const unsigned char *)buf;
+    while (len > 0) {
+        ssize_t n = write(fd, p, len);
+        if (n <= 0) return -1;
+        p += (size_t)n;
+        len -= (size_t)n;
+    }
+    return 0;
+}
+
+static int read_all(int fd, void *buf, size_t len) {
+    unsigned char *p = (unsigned char *)buf;
+    while (len > 0) {
+        ssize_t n = read(fd, p, len);
+        if (n <= 0) return -1;
+        p += (size_t)n;
+        len -= (size_t)n;
+    }
+    return 0;
+}
+
+int send_json_frame(int fd, const char *json) {
+    uint32_t n = (uint32_t)strlen(json);
+    uint32_t be = htonl(n);
+    if (write_all(fd, &be, 4) != 0) return -1;
+    if (write_all(fd, json, n) != 0) return -1;
+    return 0;
+}
+```
+
+## 9.2 Python (Unix abstract socket + frame)
+
+```python
+import json
+import socket
+import struct
+
+def send_rpc(socket_name: str, obj: dict) -> dict:
+    payload = json.dumps(obj, separators=(",", ":")).encode("utf-8")
+    frame = struct.pack(">I", len(payload)) + payload
+
+    s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+    try:
+        s.connect("\0" + socket_name)  # abstract namespace
+        s.sendall(frame)
+
+        hdr = recv_exact(s, 4)
+        ln = struct.unpack(">I", hdr)[0]
+        body = recv_exact(s, ln)
+        return json.loads(body.decode("utf-8"))
+    finally:
+        s.close()
+
+def recv_exact(s: socket.socket, n: int) -> bytes:
+    out = bytearray()
+    while len(out) < n:
+        chunk = s.recv(n - len(out))
+        if not chunk:
+            raise ConnectionError("unexpected EOF")
+        out.extend(chunk)
+    return bytes(out)
+```
+
+## 9.3 TypeScript (Node.js net + frame)
+
+```ts
+import net from "node:net";
+
+export async function sendRpc(socketName: string, request: unknown): Promise<any> {
+  const payload = Buffer.from(JSON.stringify(request), "utf8");
+  const header = Buffer.alloc(4);
+  header.writeUInt32BE(payload.length, 0);
+
+  return await new Promise((resolve, reject) => {
+    const socket = net.createConnection({ path: `\u0000${socketName}` });
+
+    let chunks: Buffer[] = [];
+    let needed = 4;
+    let mode: "header" | "body" = "header";
+
+    socket.on("connect", () => {
+      socket.write(Buffer.concat([header, payload]));
+    });
+
+    socket.on("data", (data) => {
+      chunks.push(data);
+      let buf = Buffer.concat(chunks);
+
+      while (buf.length >= needed) {
+        const part = buf.subarray(0, needed);
+        buf = buf.subarray(needed);
+
+        if (mode === "header") {
+          needed = part.readUInt32BE(0);
+          mode = "body";
+        } else {
+          socket.end();
+          resolve(JSON.parse(part.toString("utf8")));
+          return;
+        }
+      }
+
+      chunks = [buf];
+    });
+
+    socket.on("error", reject);
+    socket.on("end", () => {
+      // no-op; resolution occurs when full body is parsed
+    });
+  });
+}
+```
+
+---
+
+## 10. End-to-end transcripts
+
+## 10.1 Happy path: get public key
+
+Request:
+
+```json
+{ "id": "1", "method": "get_public_key", "params": [] }
+```
+
+Response:
+
+```json
+{ "id": "1", "result": "<hex_pubkey>" }
+```
+
+## 10.2 Happy path: sign event with explicit role
+
+Request:
+
+```json
+{
+  "id": "2",
+  "method": "sign_event",
+  "params": ["<event_json>", { "role": "main" }]
+}
+```
+
+Response:
+
+```json
+{ "id": "2", "result": "<signed_event_json>" }
+```
+
+## 10.3 Error path: unknown role
+
+Request:
+
+```json
+{
+  "id": "3",
+  "method": "sign_event",
+  "params": ["<event_json>", { "role": "does_not_exist" }]
+}
+```
+
+Response:
+
+```json
+{ "id": "3", "error": { "code": 1002, "message": "unknown_role" } }
+```
+
+## 10.4 Error path: ambiguous selector
+
+Request:
+
+```json
+{
+  "id": "4",
+  "method": "sign_event",
+  "params": [
+    "<event_json>",
+    { "role": "main", "nostr_index": 0 }
+  ]
+}
+```
+
+Response:
+
+```json
+{ "id": "4", "error": { "message": "ambiguous_role_selector" } }
+```
+
+## 10.5 Encrypt/decrypt round trip (NIP-44)
+
+Encrypt request:
+
+```json
+{
+  "id": "5",
+  "method": "nip44_encrypt",
+  "params": ["<peer_pubkey>", "hello", { "role": "main" }]
+}
+```
+
+Encrypt response:
+
+```json
+{ "id": "5", "result": "<nip44_ciphertext>" }
+```
+
+Decrypt request:
+
+```json
+{
+  "id": "6",
+  "method": "nip44_decrypt",
+  "params": ["<peer_pubkey>", "<nip44_ciphertext>", { "role": "main" }]
+}
+```
+
+Decrypt response:
+
+```json
+{ "id": "6", "result": "hello" }
+```
+
+---
+
+## 11. Compatibility notes
+
+- If you are writing an autonomous agent client, pin to explicit socket name and explicit role selector.
+- Keep method support feature-detected (`method_not_found` fallback).
+- Treat approval as asynchronous human gating even for local calls.
+- Track and surface signer name, request id, and method for auditability.

documents/FIPS_DEPLOYMENT.md

@@ -0,0 +1,177 @@
+# FIPS_DEPLOYMENT.md
+
+## 1. Scope
+
+This runbook covers a practical Tier-1 deployment of `nsigner` over a TCP listener, with connectivity provided by FIPS as the network substrate.
+
+Tier-1 objective:
+
+- Keep `nsigner` transport simple (`--listen tcp:IPv4:PORT` or `--listen tcp:[IPv6]:PORT`).
+- Use FIPS to carry traffic between peers.
+- Do not add FIPS runtime dependencies into `nsigner`.
+
+Out of scope in this document:
+
+- Mandatory transport-level TLS/authentication hardening (still planned for a later phase).
+- Automatic caller->npub enrichment from FIPS session metadata.
+
+---
+
+## 2. Architecture
+
+Two cooperating layers:
+
+1. **Signer process layer** (`nsigner`)
+   - Listens on operator-selected TCP endpoint (IPv4 or IPv6).
+   - Uses existing 4-byte big-endian framed JSON-RPC protocol.
+   - Keeps existing policy/prompt behavior.
+
+2. **Network substrate layer** (FIPS)
+   - Establishes peer connectivity between nodes/qubes.
+   - Carries application traffic to the configured signer TCP endpoint.
+
+Conceptually:
+
+`client app -> local FIPS endpoint -> FIPS mesh -> remote FIPS endpoint -> signer TCP endpoint -> nsigner`
+
+---
+
+## 3. Prerequisites
+
+On signer host/qube:
+
+- Built `nsigner` binary.
+- FIPS installed and running.
+- Local firewall policy that keeps signer listener local-only.
+
+On caller host/qube:
+
+- FIPS installed and peered with signer host/qube.
+- A client implementation that speaks `nsigner` framed JSON-RPC (see `documents/CLIENT_IMPLEMENTATION.md`).
+
+Operational assumptions:
+
+- Operator controls both endpoints.
+- Manual verification of peer identity is performed in FIPS tooling before enabling signer traffic.
+
+---
+
+## 4. Start signer in Tier-1 TCP mode
+
+Run `nsigner` in TCP listen mode:
+
+```bash
+./build/nsigner --listen tcp:[::]:8080
+```
+
+Or bind to a specific FIPS ULA address:
+
+```bash
+./build/nsigner --listen tcp:[fd00::1234]:8080
+```
+
+Behavior notes:
+
+- Bind target is operator-controlled; pick the narrowest reachable address that satisfies your topology.
+- No TUI hotkey loop is required in TCP mode; process serves requests until terminated.
+- Caller identity is shown as a TCP endpoint descriptor in activity/prompt context.
+
+---
+
+## 5. FIPS substrate wiring pattern
+
+Because FIPS deployment topologies vary, use this generic pattern:
+
+1. Bind `nsigner` on a deliberate signer endpoint (`[::]:PORT` for broad reach, or specific `fd..` for tighter scope).
+2. Configure FIPS service/forwarding so remote authenticated peer traffic is delivered to that signer endpoint.
+3. On caller side, direct client traffic to the local FIPS ingress endpoint for that remote service.
+
+Validation checklist:
+
+- FIPS session is established between caller and signer nodes.
+- Transport path from caller -> configured signer endpoint succeeds.
+- `nsigner` receives framed request and returns framed response.
+
+---
+
+## 6. Minimal validation flow
+
+### 6.1 Liveness check
+
+From caller side, send a framed `get_public_key` request through the FIPS-backed endpoint.
+
+Request JSON:
+
+```json
+{"id":"1","method":"get_public_key","params":[]}
+```
+
+Expected response:
+
+```json
+{"id":"1","result":"<hex_pubkey>"}
+```
+
+### 6.2 Signing check
+
+Send `sign_event` with explicit role selector:
+
+```json
+{
+  "id": "2",
+  "method": "sign_event",
+  "params": ["<event_json>", {"role":"main"}]
+}
+```
+
+Expected result: signed event JSON in `result`.
+
+### 6.3 Negative check (policy)
+
+Trigger a request path that requires prompt/denial and confirm client handles policy denial as a normal result path.
+
+---
+
+## 7. Security guardrails
+
+- Prefer binding to a specific FIPS IPv6 ULA (`fd..`) rather than wildcard (`[::]`) when possible.
+- Do not expose signer port directly on LAN/WAN.
+- Keep FIPS peer allowlist tight; avoid broad trust domains.
+- Treat FIPS connectivity as transport, not authorization bypass.
+- Preserve interactive approval where required by policy.
+
+---
+
+## 8. Troubleshooting
+
+### 8.1 `invalid tcp listen target`
+
+Cause:
+- `--listen` argument does not match `tcp:HOST:PORT` or `tcp:[IPv6]:PORT`.
+
+Fix:
+- Use valid numeric port and valid IPv4/IPv6 literal host.
+
+### 8.2 Framing parse failures (`parse_error`)
+
+Cause:
+- Client sent line-delimited/raw JSON instead of framed JSON.
+
+Fix:
+- Send 4-byte big-endian length prefix followed by exact UTF-8 JSON payload bytes.
+
+### 8.3 FIPS path up, signer path down
+
+Cause:
+- FIPS session exists but forwarding/service mapping to signer loopback endpoint is missing.
+
+Fix:
+- Verify substrate service routing config and local endpoint mapping.
+
+---
+
+## 9. Next hardening steps (post Tier-1)
+
+- Add automated two-node validation script for operator smoke checks.
+- Add optional identity enrichment from FIPS session metadata (`peer_npub`).
+- Introduce remote TCP mode only with mandatory TLS + authenticated caller key flow.

documents/QUBES_OS.md

@@ -0,0 +1,179 @@
+# QUBES_OS.md
+
+## 1. Goal
+
+Run `n_signer` inside a dedicated Qubes OS qube (for example `vault`-like behavior), and let caller qubes access signing via qrexec with explicit policy control.
+
+This doc outlines what must be implemented/packaged for a reliable Qubes deployment path.
+
+---
+
+## 2. Current status (where we are now)
+
+Implemented in current codebase:
+
+- `nsigner` supports `--listen qrexec` and `--listen stdio`.
+- Framing is transport-agnostic and shared via length-prefixed JSON (`4-byte big-endian length + payload`).
+- In qrexec/stdio mode, server handles one framed request-response exchange.
+- Caller identity extraction supports `QREXEC_REMOTE_DOMAIN`, surfaced as `qubes:<source-vm>` when available.
+
+Still missing for complete Qubes integration:
+
+- qrexec service file + wrapper script artifacts.
+- dom0 qrexec policy artifacts with sane defaults.
+- install/uninstall guidance and verification flow for real Qubes deployment.
+- packaging path (`packaging/qubes/`) and docs wired into README map.
+
+---
+
+## 3. Architecture in Qubes
+
+### 3.1 Components
+
+- **Signer qube** (target): runs `nsigner` service entrypoint.
+- **Caller qube(s)**: apps/tools invoking qrexec service.
+- **dom0 policy**: controls which caller qubes may invoke signer service.
+
+### 3.2 Request path
+
+1. Caller qube invokes qrexec service (e.g. `qubes.NsignerRpc`).
+2. qrexec starts service command inside signer qube.
+3. Service command runs `nsigner --listen qrexec`.
+4. Caller sends framed JSON-RPC request over qrexec stdio channel.
+5. `nsigner` returns framed JSON-RPC response.
+
+### 3.3 Trust and identity
+
+- Source qube identity comes from `QREXEC_REMOTE_DOMAIN`.
+- `n_signer` maps caller as `qubes:<source-vm>` where available.
+- qrexec policy in dom0 remains first enforcement boundary.
+- `n_signer` policy/approval remains second boundary.
+
+---
+
+## 4. Required implementation tasks
+
+## 4.1 Service entrypoint artifacts ✅ Implemented
+
+Implemented repo artifacts:
+
+- `packaging/qubes/rpc/qubes.NsignerRpc`
+- `packaging/qubes/install-service.sh`
+
+`qubes.NsignerRpc` runs:
+
+- `exec /usr/local/bin/nsigner --listen qrexec`
+
+Install inside the signer qube:
+
+```bash
+sudo sh packaging/qubes/install-service.sh
+```
+
+This installs the qrexec service to `/etc/qubes-rpc/qubes.NsignerRpc` with executable permissions.
+
+## 4.2 dom0 policy artifacts ✅ Implemented
+
+Implemented repo artifacts:
+
+- `packaging/qubes/policy.d/40-nsigner.policy`
+- `packaging/qubes/install-policy.sh`
+
+Policy defaults now use explicit `ask` plus deny catch-all:
+
+- `qubes.NsignerRpc * @anyvm @tag:nsigner-signer ask default_target=nsigner-vault`
+- `qubes.NsignerRpc * @anyvm @anyvm deny`
+
+Install in dom0:
+
+```bash
+sudo sh packaging/qubes/install-policy.sh
+```
+
+This installs `/etc/qubes/policy.d/40-nsigner.policy` and prints signer-tag guidance.
+
+## 4.3 Policy model inside n_signer for qubes callers ✅ Implemented
+
+Current code reads caller as `qubes:<vm>` and qrexec default behavior is hardened.
+
+In qrexec mode, default prompt behavior is now:
+
+- `PROMPT_EVERY_REQUEST`
+
+This replaces the previous permissive `PROMPT_NEVER` temporary setting.
+
+## 4.4 Client helper examples ✅ Implemented
+
+Added:
+
+- `documents/qubes_client_examples.md`
+
+Includes:
+
+- shell helper example invoking `qrexec-client-vm` with framed request/response handling
+- Python helper example implementing frame encode/decode over qrexec stdio channel
+- reference to `documents/CLIENT_IMPLEMENTATION.md` for full protocol details
+
+---
+
+## 5. Operational runbook
+
+## 5.1 Setup signer qube
+
+- install `nsigner` binary at `/usr/local/bin/nsigner`
+- run `sudo sh packaging/qubes/install-service.sh`
+- verify `/etc/qubes-rpc/qubes.NsignerRpc` exists and is executable
+
+## 5.2 Setup dom0 policy
+
+- run `sudo sh packaging/qubes/install-policy.sh`
+- tag signer qube (example): `qvm-tags nsigner-vault add nsigner-signer`
+- reload qrexec policy per Qubes procedure/version
+
+## 5.3 Verification
+
+- from caller qube, invoke test request (`get_public_key`)
+- confirm signer qube receives request
+- confirm activity log displays `qubes:<source-vm>` caller prefix
+- validate deny behavior from unauthorized qube
+
+## 5.4 Failure checks
+
+- malformed frame -> parse error response
+- missing policy -> deny path
+- missing `QREXEC_REMOTE_DOMAIN` -> fallback identity path
+
+---
+
+## 6. Security requirements
+
+- Never run signer service in disposable qube if mnemonic persistence is expected.
+- Prefer dedicated minimal template for signer qube.
+- Keep qrexec policy narrowly scoped (explicit source + target).
+- Require user approval for sensitive methods unless explicitly intended otherwise.
+- Log caller identity and method (without secret payload logging).
+
+---
+
+## 7. Documentation tasks
+
+Update these after packaging lands:
+
+- `README.md`
+  - add Qubes deployment subsection under transport/usage
+  - add `documents/QUBES_OS.md` and moved `documents/CLIENT_IMPLEMENTATION.md` in document map
+- `plans/nsigner.md`
+  - mark T1 done with packaging status clearly separated
+
+---
+
+## 8. Definition of done (Qubes)
+
+Qubes integration is considered complete when:
+
+1. qrexec service artifact exists and is installable.
+2. dom0 policy artifact exists with secure default pattern.
+3. End-to-end call from allowed caller qube succeeds.
+4. Call from unauthorized qube is denied.
+5. Caller displayed as `qubes:<vm>` in activity.
+6. README + docs include full setup and troubleshooting.

documents/SECURITY.md

@@ -0,0 +1,514 @@
+# SECURITY.md
+
+This document explains how `n_signer` enforces security, written so someone new can understand the model end-to-end without reading the source.
+
+If you only read one section, read [§3 The three concepts](#3-the-three-concepts-identity-index-approval) and [§4 The deny-by-default rule](#4-the-deny-by-default-rule).
+
+> This document describes the security model as implemented in the current release. Design rationale is in [`plans/deny_by_default_approvals.md`](../plans/deny_by_default_approvals.md).
+
+---
+
+## 1. What `n_signer` is, in security terms
+
+`n_signer` is a **single foreground program** that holds a BIP-39 mnemonic in locked memory and signs requests on behalf of local clients. It is not a daemon, not a service, and not a key-management database.
+
+The security posture is intentionally minimalist:
+
+- **One process. One terminal. One human.** The terminal is the trust anchor and the only out-of-band approval surface.
+- **No persistence.** Nothing about the running session is written to disk: no config, no logs, no PID files, no socket pathnames, no state recovery.
+- **Crash equals total wipe.** All sensitive state — mnemonic, derived keys, the policy table, activity buffer — exists only in process RAM (`mlock`'d where applicable) and is unrecoverable after the process ends.
+- **Always-attended operation.** Every first request from a previously unknown caller requires an explicit human approval at the terminal, unless the caller was pre-approved at startup by the OS distribution. Human presence is part of the threat model, not an inconvenience.
+
+Authoritative behavior reference: [`README.md`](../README.md). Implementation roadmap: [`plans/nsigner.md`](../plans/nsigner.md). Approval model plan: [`plans/deny_by_default_approvals.md`](../plans/deny_by_default_approvals.md). Wire contract for clients: [`documents/CLIENT_IMPLEMENTATION.md`](CLIENT_IMPLEMENTATION.md).
+
+---
+
+## 2. Threat model
+
+### 2.1 What `n_signer` is designed to defend against
+
+- **Untrusted local clients** asking the signer to perform operations they should not be allowed to perform.
+- **Drive-by signing** — an unattended program quietly producing signatures the user did not consent to.
+- **Accidental misuse** — a buggy client connecting to the wrong signer instance, or asking for an identity it should not be using.
+- **Post-mortem key recovery** — someone obtaining the disk after a crash, kill, or shutdown and recovering signing keys.
+
+### 2.2 What `n_signer` does **not** defend against
+
+- A compromised kernel or hypervisor (`mlock` cannot save you).
+- Physical access while the program is running and the terminal is unlocked.
+- A malicious user who knows the mnemonic — `n_signer` is a runtime gatekeeper, not a vault.
+- Side channels (timing, power, microarchitectural) that target the underlying crypto libraries.
+- Network adversaries when transports without authentication are explicitly enabled (e.g. `tcp_local`).
+- An OS distribution that ships a malicious `--preapprove` list in its system unit files. The OS is in scope of trust if it pre-approves anything; see [§7](#7-pre-approvals-the-os-distribution-pathway).
+
+### 2.3 Trust anchors
+
+| Anchor | Why it is trusted |
+|---|---|
+| The terminal `n_signer` is attached to | The user types the mnemonic into it and answers approval prompts on it. If the terminal is compromised, the session is compromised. |
+| The kernel and `mlock` / `getrandom` syscalls | Used for in-memory protection and entropy. |
+| The static binary itself | Built reproducibly via [`build_static.sh`](../build_static.sh) and shipped as one musl-static artifact. |
+| The launcher that started `n_signer` | Whoever ran the process chose the `--preapprove` flags. In interactive use that's the human; in `n_OS_tr` boot it's the OS init system. The launcher's integrity is part of the trust chain. |
+
+Everything else — clients, other processes, other users, remote callers — is **untrusted by default** and must clear an approval check.
+
+---
+
+## 3. The three concepts: identity, index, approval
+
+This is the entire user-facing security model. There are exactly three things to know.
+
+```text
+   +----------------+         +-----------------------+         +---------------+
+   |  IDENTITY      |         |  INDEX (or PATH)      |         |  APPROVAL     |
+   |  who is asking |  +----  |  which key to use     |  ----+  |  is this OK?  |
+   +----------------+  |      +-----------------------+      |  +---------------+
+                       |                                     |
+                       |       request resolves to           |
+                       +-------> (identity, index/path) -----+
+                                                             |
+                                                             v
+                                                +----------------------------+
+                                                |  Approved entry exists?    |
+                                                +----------------------------+
+                                                   |yes              |no
+                                                   v                 v
+                                          +-----------------+  +----------------+
+                                          | Sign / encrypt  |  | Prompt human   |
+                                          +-----------------+  +----------------+
+                                                                       |
+                                                          [y]/[a]      |     [n]
+                                                          allow now    |     deny
+                                                          /save        |
+                                                          v            v
+                                                  +-----------------+ +----------------+
+                                                  | Sign / encrypt  | | policy_denied  |
+                                                  +-----------------+ +----------------+
+```
+
+### Identity — *who is asking*
+
+An identity is a tagged caller record built from the transport. Different transports produce different identity tags; the signer never invents identity, it always reads it from the kernel or framework.
+
+| Kind | What it carries | Source of truth |
+|---|---|---|
+| `unix_peer` | `uid`, `pid` from `SO_PEERCRED` on an abstract Unix socket. | Kernel — the client cannot forge it. |
+| `qubes` | source qube name from `QREXEC_REMOTE_DOMAIN`. | Qubes RPC framework. |
+| `tcp_local` | Loopback address of caller. | TCP socket peer address — opt-in transport. |
+| `tcp_remote` | Address plus an authenticated pubkey (planned). | Application-layer authentication. |
+| `fips` | Peer npub from a NIP-46 style flow (planned). | Application-layer authentication. |
+| `usb_serial` | Device path plus an asserted caller (planned). | Trust-on-first-use. |
+
+Identity quality varies. `unix_peer` and `qubes` are vouched for by the kernel or hypervisor — strong. `tcp_local` and `tcp_remote` are transport-asserted only — only as good as the human at the terminal who chose to approve them.
+
+### Index (or path) — *which key*
+
+The signer can derive many keys from one mnemonic. Clients select one in two equivalent ways:
+
+- `nostr_index = N` — shorthand for the Nostr derivation `m/44'/1237'/N'/0/0` per NIP-06.
+- `role_path = "<full BIP-32 path>"` — used for non-Nostr key trees (Bitcoin, SSH, etc.). Pre-registered only; see [§9.2](#92-pre-registration-of-role_path).
+
+The three legacy selector words from the wire protocol — `role`, `nostr_index`, `role_path` — all resolve to a single internal record. From the user's perspective, what matters is "which Nostr identity (by index)" or "which advanced derivation (by path)."
+
+
+### Approval — *is this OK?*
+
+An approval is an in-memory entry that says: *"this identity may use this index/path."* Approvals come from exactly two sources:
+
+1. **The human at the prompt.** When a request arrives that has no matching approval, the signer blocks the request and asks the user. On `[a]` ("allow this caller for this index/path for the rest of the session") the signer adds a session approval. On `[y]` it allows once without saving. On `[n]` it denies.
+2. **Pre-approvals.** When the OS distribution starts `n_signer` with `--preapprove caller=...,nostr_index=...` flags, those become approvals that exist before any request arrives. They never trigger prompts. See [§7](#7-pre-approvals-the-os-distribution-pathway).
+
+Approvals are stored in an in-memory table and vanish on process exit. There is no persistent approval database.
+
+
+---
+
+## 4. The deny-by-default rule
+
+`n_signer` denies any request whose `(identity, index)` pair has no approval. Period.
+
+There is no special case for "same-uid" callers. There is no implicit grant for the user running their own client. Every first request from every caller goes through an approval — either granted by the user at the prompt, or pre-approved by the OS distribution at startup.
+
+This is the single most important property:
+
+- It removes the assumption that "same-uid means trusted" — an assumption that was always more convenience than security.
+- It collapses several mechanisms (policy, role pre-registration, the `[a]` flag) into one (the in-memory approval table).
+- It makes the audit trail trivial: every signed operation maps to either a pre-approval declaration or a logged human approval.
+
+
+---
+
+## 5. The two checks every request must pass
+
+Every signing request runs through this short pipeline. Failure at any step returns an error response and is logged.
+
+```text
+   +----------------------------------------------------------------+
+   | 1. CLIENT                                                      |
+   |    sends length-prefixed JSON-RPC request                      |
+   +----------------------------------------------------------------+
+                                |
+                                v
+   +----------------------------------------------------------------+
+   | 2. TRANSPORT                                                   |
+   |    - reads framed bytes off the socket                         |
+   |    - builds caller_identity_t (uid / qubes vm / tcp peer / ...)|
+   +----------------------------------------------------------------+
+                                |
+                                v
+   +----------------------------------------------------------------+
+   | 3. RESOLVE INDEX                                               |
+   |    - parse selector options from request                       |
+   |    - resolve to a specific (index or path)                     |
+   |    - reject ambiguous selectors                                |
+   +----------------------------------------------------------------+
+                                |
+                                v
+   +----------------------------------------------------------------+
+   | 4. APPROVAL CHECK                                              |
+   |    - is there an approval for (this identity, this index)?     |
+   |        yes  -> ALLOW                                           |
+   |        no   -> PROMPT human (or DENY if non-interactive)       |
+   |    - on [a], append a session approval and continue            |
+   |    - on [y], continue this request only                        |
+   |    - on [n] / EOF, deny                                        |
+   +----------------------------------------------------------------+
+                                |
+                                v
+   +----------------------------------------------------------------+
+   | 5. ENFORCEMENT (verb x purpose x curve)                        |
+   |    - is this verb compatible with the key's declared purpose?  |
+   |    - reject with purpose_mismatch / curve_mismatch otherwise   |
+   +----------------------------------------------------------------+
+                                |
+                                v
+   +----------------------------------------------------------------+
+   | 6. KEY DERIVATION + SIGN                                       |
+   |    - derive key from mnemonic at the resolved path             |
+   |    - perform crypto operation                                  |
+   |    - return signed result                                      |
+   +----------------------------------------------------------------+
+                                |
+                                v
+   +----------------------------------------------------------------+
+   | 7. RESPONSE FRAMED + SENT                                      |
+   |    - activity log line appended with the approval source label |
+   +----------------------------------------------------------------+
+```
+
+There are two independent gates: the **approval check** (does this caller have permission to use this key?) and the **enforcement check** (is this operation compatible with this key?). Both must pass.
+
+### 5.1 Approval check — *does this caller have permission?*
+
+Implemented as a lookup in the in-memory approval table. First match wins; the catch-all is `*` → deny. No approval entry, no signature.
+
+The approval check answers *who* and *which key*. It does not check what the request will do with the key — that is the enforcement check.
+
+### 5.2 Enforcement check — *is this operation compatible with this key?*
+
+The signer enforces a strict `(verb, purpose, curve)` matrix:
+
+| Verb | Required purpose | Required curve |
+|---|---|---|
+| `sign_event` | `nostr` | `secp256k1` |
+| `get_public_key` | `nostr` | `secp256k1` |
+| `nip04_encrypt` / `nip04_decrypt` | `nostr` | `secp256k1` |
+| `nip44_encrypt` / `nip44_decrypt` | `nostr` | `secp256k1` |
+| Any other verb | rejected | rejected |
+
+A pre-approval to use a Bitcoin-purposed key for `sign_event` does **not** override the enforcement matrix. The approval grants access to the key; enforcement still gates the verb. **Fail-closed**: unknown verbs are rejected, never passed through.
+
+This is the layer that prevents (for example) a `bitcoin/secp256k1` key from being used to sign a Nostr event even if some pre-approval entry mistakenly named it. The key's *purpose* is part of its identity; you cannot reuse it across domains.
+
+Test coverage: [`tests/test_enforcement.c`](../tests/test_enforcement.c).
+
+---
+
+## 6. The interactive approval prompt
+
+When a request has no matching approval and `n_signer` is running attached to a terminal, the signer blocks the request, prints a prompt, and waits for a local keystroke.
+
+Target prompt format:
+
+```
+Approval required
+caller:    qubes:nostr-relay
+verb:      sign_event
+index:     nostr_index=0
+purpose:   nostr / secp256k1
+
+[y] allow once
+[a] allow this caller for index 0 for the rest of the session
+[n] deny
+```
+
+The keys mean:
+
+- `[y]` — Allow this single request. No approval is saved; the next request from the same caller will prompt again.
+- `[a]` — Allow, and add a session approval so the same `(caller, index)` pair is silently allowed for the rest of the session.
+- `[n]` — Deny this request. Returns `policy_denied` to the client.
+- EOF / non-interactive — Treated as deny. There is no implicit "allow when nobody is at the terminal" mode. OS distributions that need silent operation use [`--preapprove`](#7-pre-approvals-the-os-distribution-pathway).
+
+### 6.1 What `[a]` does and does not do
+
+- It approves the **specific caller** (e.g. `qubes:nostr-relay`).
+- It approves the **specific index/path** that triggered the prompt.
+- It does **not** approve other callers.
+- It does **not** approve other indices for the same caller — a different `nostr_index` from the same caller will prompt again.
+- It does **not** persist past the process lifetime.
+
+
+### 6.2 New-identity warning
+
+When a request specifies an unregistered `nostr_index`, the prompt says so plainly:
+
+```
+Approval required
+caller:    qubes:nostr-relay
+verb:      get_public_key
+index:     nostr_index=7  (NEW IDENTITY — will be derived if approved)
+
+[y] allow once    [a] allow caller for this new identity    [n] deny
+```
+
+A new identity is just a new derivation of the same mnemonic. It is not a separate key file or a separate seed; it is `m/44'/1237'/7'/0/0` of the existing mnemonic. The user should still see explicitly that they are *creating* a previously-unused identity.
+
+### 6.3 Race-condition behavior
+
+Requests are served one at a time. If a malicious client tries to flood requests during a prompt, only the request being prompted is held; subsequent requests queue or are dropped per the transport's framing. The prompt always names the request being approved. It is not possible for a queued request to "ride along" on an approval intended for an earlier request.
+
+---
+
+## 7. Pre-approvals: the OS distribution pathway
+
+For deployments where multiple system services need keys at boot — `n_OS_tr` and similar — the OS distribution starts `n_signer` with one `--preapprove` flag per service:
+
+```ini
+[Service]
+ExecStart=/usr/bin/n_signer \
+  --preapprove caller=qubes:nostr-relay,role=main \
+  --preapprove caller=qubes:dm-handler,nostr_index=1 \
+  --preapprove caller=qubes:contacts,nostr_index=2 \
+  --preapprove caller=qubes:zaps,nostr_index=3
+```
+
+At startup, `n_signer`:
+
+1. Parses each flag into an approval entry with prompt mode `NEVER`.
+2. Auto-derives any keys those entries depend on (so services don't see "ready" until keys exist).
+3. Writes one log line per pre-approval to stderr so the OS unit's journal records what was authorized.
+4. Begins listening normally. Pre-approved requests are served silently; everything else still hits the prompt or the catch-all deny.
+
+### 7.1 What pre-approvals can do
+
+- Allow a specific named caller to use a specific named key for any verb that key's purpose/curve permits.
+- Auto-create a Nostr identity at a specified `nostr_index` if it does not yet exist.
+- Be inspected: anyone reading the systemd unit (or `ps` output) can see exactly what was authorized.
+
+### 7.2 What pre-approvals cannot do
+
+- **Cannot deny.** Pre-approvals only widen authorization, never narrow it. The user at the terminal is always the source of denial. (The plan deliberately rejects "preapprove deny" entries; see [`plans/deny_by_default_approvals.md`](../plans/deny_by_default_approvals.md) §C.3.)
+- **Cannot wildcard the caller.** Each entry must name exactly one caller. There is no `qubes:*` rule. The OS distribution must know who its services are.
+- **Cannot bypass enforcement.** A pre-approval to use a Nostr key for a hypothetical Bitcoin verb still fails the enforcement matrix in [§5.2](#52-enforcement-check--is-this-operation-compatible-with-this-key).
+- **Cannot pre-register `role_path` derivations.** Only `role=<name>` (an existing role) and `nostr_index=<n>` are allowed in pre-approval specs. Free-form `role_path` derivations remain pre-registration-only by code path. See [§9.2](#92-pre-registration-of-role_path).
+
+### 7.3 Trust implications
+
+Pre-approvals shift the trust boundary. Whoever wrote the systemd unit now decides what the signer will allow without asking. Concretely:
+
+- The unit file's integrity matters. If an attacker can rewrite it, they can pre-approve themselves.
+- The OS launcher's identity-stamping must be trustworthy. If something else can spoof a `qubes:nostr-relay` tag, it inherits that pre-approval.
+- The user retains final authority at the running terminal. Anything *not* pre-approved still goes through the human-approved prompt.
+
+In `n_OS_tr` these properties are part of the OS itself: the unit files are owned by root, the qrexec framework stamps caller identity at the hypervisor level, and the user's terminal is the ultimate arbiter. The trust chain is short and visible.
+
+
+---
+
+## 8. The audit log
+
+Every served (or denied) request appends a line to the in-memory activity buffer that the running TUI displays. Each line includes the **source label** that explains why the verdict was reached.
+
+Target line format:
+
+```
+[2026-05-04 16:03:11] qubes:nostr-relay  sign_event(nostr_index=0)  ALLOWED:preapprove
+[2026-05-04 16:03:14] uid:1000           sign_event(nostr_index=0)  ALLOWED:session-grant
+[2026-05-04 16:03:18] tcp:[::1]:54122    get_public_key(nostr_index=7) ALLOWED:prompt
+[2026-05-04 16:03:21] uid:1001           sign_event(nostr_index=0)  DENIED:no-match
+```
+
+Source labels:
+
+| Label | Meaning |
+|---|---|
+| `:preapprove` | Approval came from a `--preapprove` startup flag. |
+| `:session-grant` | Approval was added earlier this session by a prompt `[a]`. |
+| `:prompt` | Approval was given just now by the user pressing `[y]` or `[a]` at the prompt. |
+| `:no-match` | No approval existed and (in non-interactive mode) the request was denied. |
+
+This makes forensic review fast: every signed operation maps to either a pre-approval (audit the unit file), a session grant (audit the session's earlier prompt activity), or a fresh prompt approval (audit human attention at that moment).
+
+
+---
+
+## 9. The role abstraction (internal plumbing)
+
+Internally `n_signer` uses a structure called a **role** to bundle three things together:
+
+- A derivation path (BIP-32).
+- A purpose label (`nostr`, `bitcoin`, `ssh`, `age`).
+- A curve label (`secp256k1`, `ed25519`, `x25519`).
+
+Roles are the unit of *enforcement* (the matrix in [§5.2](#52-enforcement-check--is-this-operation-compatible-with-this-key) is keyed on role purpose and curve) and the unit of *audit* (every log line names the role used).
+
+### 9.1 Why roles exist as plumbing rather than user-facing concept
+
+- A future where one mnemonic produces Nostr, Bitcoin, SSH, and age keys requires *something* to track per-key purpose. Roles are that thing. Keeping them in the codebase preserves the option without forcing the user to think about them today.
+- Two different identities can use the same role (the same key). The role is the audit unit shared between them, so the activity log is consistent regardless of caller.
+- Enforcement against a role's declared purpose/curve is a defense-in-depth: a Nostr key cannot be coerced into producing a Bitcoin signature even if some approval entry mistakenly named it.
+
+A user reading prompts and the activity log will see "index 0" and "index 7" most of the time, not "role main" or "role nostr_idx_7." Roles surface as labels only in advanced views and the source code.
+
+### 9.2 Pre-registration of `role_path`
+
+The `role_path` selector lets a client specify a BIP-32 path directly, including paths outside the Nostr derivation scheme. These remain **pre-registration-only**:
+
+- The signer ships with an empty `role_path` table.
+- Operators who want non-Nostr keys must register them at startup (mechanism TBD).
+- The interactive prompt does **not** auto-derive `role_path` keys, even with `[a]`. The narrowing in [`plans/deny_by_default_approvals.md`](../plans/deny_by_default_approvals.md) §5 explicitly applies only to `nostr_index`.
+
+The reasoning is that `role_path` is free-form. A malicious or buggy client could request paths that overlap with sensitive domains (bitcoin wallet roots, SSH host keys, age recipients). Auto-derivation in those domains would be a footgun. `nostr_index` is locked to a specific scheme with locked purpose and curve, so auto-derivation there is safe to gate on a single human keystroke.
+
+### 9.3 Role table size limits
+
+`ROLE_TABLE_MAX_ENTRIES` caps the number of distinct roles per session. The plan raises this to 256. Overflow is reported as a clear `role_table_full` error rather than silent truncation or memory unsafety.
+
+---
+
+## 10. Memory safety and zeroization
+
+### 10.1 Locked memory
+
+- The mnemonic and derived private keys live in `mlock`'d allocations managed by [`src/secure_mem.c`](../src/secure_mem.c).
+- These pages are pinned in RAM (no swap to disk) for the process lifetime.
+- On normal shutdown (`q`, `SIGINT`, `SIGTERM`), buffers are explicitly zeroized before unmap.
+
+### 10.2 Crash semantics
+
+If the process dies abnormally, the kernel reclaims its pages. Anything previously `mlock`'d is not flushed to disk because it never could be. There is no swap residue to scrape, no core dump containing keys (if your environment disables core dumps for setuid-equivalent processes — verify locally), and no recovery path.
+
+This is the meaning of "crash equals total wipe is a security feature" in [`plans/nsigner.md:154`](../plans/nsigner.md:154).
+
+### 10.3 No persistence by design
+
+There is no file under `~/.nsigner`, no `/var/lib/nsigner`, no `~/.config/nsigner`, no approval database. The signer is a process whose authority begins when you type the mnemonic and ends when you quit.
+
+If you want something durable: store the mnemonic on paper or hardware, not in `n_signer`.
+
+The only file inputs are `--preapprove` flags from the launcher's command line, evaluated once at startup and never re-read. There is no live config reload.
+
+---
+
+## 11. Transports and their identity quality
+
+Different transports give different identity quality. The wire format (4-byte length prefix + JSON-RPC) and the security checks ([§5](#5-the-two-checks-every-request-must-pass)) are identical across transports.
+
+### 11.1 Abstract namespace Unix sockets (default)
+
+- Address: `@nsigner_<word1>_<word2>` per [`plans/nsigner.md:96`](../plans/nsigner.md:96).
+- Identity: kernel-vouched `uid`, `pid`. Cannot be forged by the client.
+- Risk surface: any local process on the same host. Deny-by-default + per-(caller, index) approvals handle this.
+
+### 11.2 Stdio / qrexec mode
+
+- One framed request, one framed response, then exit.
+- Identity: `qubes:<vm-name>` from `QREXEC_REMOTE_DOMAIN`, vouched for by Qubes.
+- Risk surface: only what Qubes RPC policy permits. See [`packaging/qubes/`](../packaging/qubes/).
+
+### 11.3 TCP (advanced / opt-in)
+
+- Loopback addresses produce `tcp_local` identities. Remote addresses produce `tcp_remote` identities.
+- Identity is **transport-asserted only**. The TCP peer address proves a route, not a principal.
+- For TCP transports the **interactive approval prompt is the real authentication mechanism**. Do not enable TCP transports without a trustworthy local terminal.
+
+### 11.4 Future transports
+
+The roadmap ([`plans/nsigner.md:178`](../plans/nsigner.md:178)) describes additional transports (USB serial, FIPS-style relay). The contract is:
+
+- The transport produces a `caller_identity_t`.
+- The same approval / enforcement / dispatch stack runs unchanged.
+- New transports add new identity *kinds*, not new bypass paths.
+
+---
+
+## 12. Operational guidance
+
+### 12.1 Running interactively (typical desktop use)
+
+- Start `n_signer` only on a terminal you control. No `--preapprove` flags.
+- Type or generate the mnemonic. Generated mnemonics are shown once with no confirmation step ([`plans/nsigner.md:84`](../plans/nsigner.md:84)) — write them down before pressing a key.
+- Stay near the terminal for the first couple of minutes after launch. New clients will prompt for approval. Press `[a]` to grant for the session.
+- Once your usual clients are approved, prompts stop appearing.
+
+### 12.2 Running as a system signer (e.g. `n_OS_tr`)
+
+- Configure pre-approvals in the systemd (or equivalent) unit file. One `--preapprove` flag per service.
+- Verify each pre-approval's caller identity exactly matches what the launcher actually produces. Mismatches cause silent deny (`:no-match` in the log).
+- Treat the unit file as security-sensitive. Restrict write access to root or its equivalent.
+- Keep a terminal attached or piped to where prompts can still be seen. Anything not pre-approved still prompts.
+
+### 12.3 Stopping
+
+- Press `q` for clean shutdown.
+- `Ctrl+C` and `SIGTERM` are equivalent — they zeroize and exit.
+- Closing the terminal is also equivalent. There is no "detach" mode by design.
+
+### 12.4 Auditing
+
+- The activity buffer in the running TUI is the session log. It does not survive the process.
+- For persistent audit, run `n_signer` under a logging supervisor that captures stderr/stdout, knowing the activity buffer reflects post-approval decisions only.
+
+### 12.5 Rotating
+
+- "Rotate" in `n_signer` means: quit, change mnemonic source, restart. There is no in-place rotation because there is no persistent state to migrate.
+
+---
+
+## 13. Relationship to the current codebase
+
+All stages from [`plans/deny_by_default_approvals.md`](../plans/deny_by_default_approvals.md) are implemented in the current codebase. This document therefore describes shipped behavior, not a future target state.
+
+---
+
+## 14. Things that look like bugs but are security features
+
+| Symptom | Reason |
+|---|---|
+| First request from a new client prompts even though it's the same uid | Deny-by-default. Same-uid trust is gone. Press `[a]` once and you won't see prompts from this client again this session. |
+| Killing the process loses all approvals and key derivations | Crash-equals-wipe. Restart with the same mnemonic to rebuild deterministically; re-approve clients. |
+| `purpose_mismatch` when calling `sign_event` against a non-Nostr key | Roles are scoped by purpose. Approvals do not bypass enforcement. |
+| `unknown_role` for an unregistered `role_path` | `role_path` keys are pre-registration-only by design. Use `nostr_index` for ad-hoc Nostr identities. |
+| Pre-approval entry doesn't match incoming requests | Caller identity must match exactly — no wildcards. Verify the launcher tags requests the way the unit file expects. |
+| `role=unknown` in the activity log (current code) | Selector did not resolve. Future versions will prompt to create the identity; current code rejects with `unknown_role` after policy passes. |
+
+---
+
+## 15. Quick reference — the security guarantee in one paragraph
+
+`n_signer` will never sign with a key whose use has not been explicitly approved — either by a human keystroke at the running terminal or by a `--preapprove` flag declared at startup. It will never use a key outside its declared `(purpose, curve)` scope. It will never expose a private key to a client. It will never write key material to disk. Every request is checked twice: once for approval, once for enforcement. Default policy is deny. Approvals vanish on process exit.
+
+If any of these statements becomes false in code, that is a security bug worth filing immediately.
+
+---
+
+## 16. References
+
+- [`README.md`](../README.md) — authoritative behavior spec.
+- [`plans/nsigner.md`](../plans/nsigner.md) — root design plan and decisions log.
+- [`plans/deny_by_default_approvals.md`](../plans/deny_by_default_approvals.md) — the approval model plan this document tracks.
+- [`documents/CLIENT_IMPLEMENTATION.md`](CLIENT_IMPLEMENTATION.md) — wire contract for clients.
+- [`documents/QUBES_OS.md`](QUBES_OS.md) — Qubes RPC integration.
+- [`documents/FIPS_DEPLOYMENT.md`](FIPS_DEPLOYMENT.md) — FIPS-mode deployment notes.
+- [`plans/seed_phrase_uses.md`](../plans/seed_phrase_uses.md) — what one mnemonic can become.
+- [`src/policy.c`](../src/policy.c), [`src/server.c`](../src/server.c), [`src/dispatcher.c`](../src/dispatcher.c), [`src/role_table.c`](../src/role_table.c), [`src/selector.c`](../src/selector.c), [`src/enforcement.c`](../src/enforcement.c) — the security-related code.

documents/qubes_client_examples.md

@@ -0,0 +1,93 @@
+# qubes_client_examples.md
+
+This document shows minimal caller-qube examples for invoking `nsigner --listen qrexec` through Qubes qrexec.
+
+For complete protocol details (framing, JSON-RPC, error handling), see `documents/CLIENT_IMPLEMENTATION.md`.
+
+---
+
+## 1) Shell example (`qrexec-client-vm` + framed JSON)
+
+This sends one `get_public_key` request and decodes one framed response.
+
+```bash
+#!/bin/sh
+set -eu
+
+TARGET_QUBE="nsigner-vault"
+SERVICE="qubes.NsignerRpc"
+REQ='{"id":"1","method":"get_public_key","params":[]}'
+
+python3 - "$TARGET_QUBE" "$SERVICE" "$REQ" <<'PY'
+import json
+import struct
+import subprocess
+import sys
+
+target, service, req_json = sys.argv[1], sys.argv[2], sys.argv[3]
+frame = struct.pack(">I", len(req_json.encode("utf-8"))) + req_json.encode("utf-8")
+
+p = subprocess.Popen(
+    ["qrexec-client-vm", target, service],
+    stdin=subprocess.PIPE,
+    stdout=subprocess.PIPE,
+)
+out, _ = p.communicate(frame)
+if p.returncode != 0:
+    raise SystemExit(f"qrexec-client-vm failed: {p.returncode}")
+if len(out) < 4:
+    raise SystemExit("short response (missing frame header)")
+
+n = struct.unpack(">I", out[:4])[0]
+payload = out[4:4+n]
+if len(payload) != n:
+    raise SystemExit("short response payload")
+
+print(json.dumps(json.loads(payload.decode("utf-8")), indent=2))
+PY
+```
+
+---
+
+## 2) Python example (explicit frame helpers over qrexec stdio)
+
+```python
+#!/usr/bin/env python3
+import json
+import struct
+import subprocess
+
+
+def frame_encode(obj: dict) -> bytes:
+    payload = json.dumps(obj, separators=(",", ":")).encode("utf-8")
+    return struct.pack(">I", len(payload)) + payload
+
+
+def frame_decode(buf: bytes) -> dict:
+    if len(buf) < 4:
+        raise ValueError("missing frame header")
+    n = struct.unpack(">I", buf[:4])[0]
+    payload = buf[4:4 + n]
+    if len(payload) != n:
+        raise ValueError("short frame payload")
+    return json.loads(payload.decode("utf-8"))
+
+
+def call_nsigner_qrexec(target_qube: str, request: dict) -> dict:
+    proc = subprocess.Popen(
+        ["qrexec-client-vm", target_qube, "qubes.NsignerRpc"],
+        stdin=subprocess.PIPE,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+    )
+    out, err = proc.communicate(frame_encode(request))
+    if proc.returncode != 0:
+        raise RuntimeError(f"qrexec failed ({proc.returncode}): {err.decode('utf-8', 'replace')}")
+    return frame_decode(out)
+
+
+if __name__ == "__main__":
+    req = {"id": "1", "method": "get_public_key", "params": []}
+    resp = call_nsigner_qrexec("nsigner-vault", req)
+    print(json.dumps(resp, indent=2))
+```

increment_and_push.sh

@@ -84,18 +84,23 @@ update_version_in_header() {
     local major="$2"
     local minor="$3"
     local patch="$4"
+    local version_file=""
 
-    if [[ ! -f "src/main.h" ]]; then
-        print_error "src/main.h not found"
+    if [[ -f "src/main.h" ]]; then
+        version_file="src/main.h"
+    elif [[ -f "src/main.c" ]]; then
+        version_file="src/main.c"
+    else
+        print_error "Neither src/main.h nor src/main.c found"
         exit 1
     fi
 
-    sed -i "s/#define NSIGNER_VERSION \".*\"/#define NSIGNER_VERSION \"$new_version\"/" src/main.h
-    sed -i "s/#define NSIGNER_VERSION_MAJOR [0-9]\+/#define NSIGNER_VERSION_MAJOR $major/" src/main.h
-    sed -i "s/#define NSIGNER_VERSION_MINOR [0-9]\+/#define NSIGNER_VERSION_MINOR $minor/" src/main.h
-    sed -i "s/#define NSIGNER_VERSION_PATCH [0-9]\+/#define NSIGNER_VERSION_PATCH $patch/" src/main.h
+    sed -i "s/#define NSIGNER_VERSION \".*\"/#define NSIGNER_VERSION \"$new_version\"/" "$version_file"
+    sed -i "s/#define NSIGNER_VERSION_MAJOR [0-9]\+/#define NSIGNER_VERSION_MAJOR $major/" "$version_file"
+    sed -i "s/#define NSIGNER_VERSION_MINOR [0-9]\+/#define NSIGNER_VERSION_MINOR $minor/" "$version_file"
+    sed -i "s/#define NSIGNER_VERSION_PATCH [0-9]\+/#define NSIGNER_VERSION_PATCH $patch/" "$version_file"
 
-    print_success "Updated src/main.h to $new_version"
+    print_success "Updated $version_file to $new_version"
 }
 
 increment_version() {
@@ -239,13 +244,7 @@ main() {
     check_git_repo
 
     if [[ "$RELEASE_MODE" == true ]]; then
-        if [[ "$VERSION_INCREMENT_EXPLICIT" == true ]]; then
-            increment_version "$VERSION_INCREMENT_TYPE"
-        else
-            LATEST_TAG=$(git tag -l 'v*.*.*' | sort -V | tail -n 1 || echo "v0.0.1")
-            NEW_VERSION="$LATEST_TAG"
-            export NEW_VERSION
-        fi
+        increment_version "$VERSION_INCREMENT_TYPE"
 
         if git tag "$NEW_VERSION" > /dev/null 2>&1; then
             print_success "Created tag: $NEW_VERSION"

install_qube_fips_nsigner.sh

@@ -0,0 +1,223 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# User-only installer for Qubes AppVM persistence model.
+# Nothing is written to /usr, /etc, or other root-owned paths.
+#
+# Installs into $HOME:
+#   - nsigner -> ~/.local/bin/nsigner
+#   - startup helper -> ~/start_nsigner.sh
+#
+# Usage:
+#   bash install_qube_fips_nsigner.sh
+#   bash install_qube_fips_nsigner.sh --help
+#
+# Optional env vars:
+#   NSIGNER_VERSION=vX.Y.Z         # optional override; default is latest release tag
+#   NSIGNER_GITEA_TOKEN=<token>    # if n_signer release assets are private
+#   NSIGNER_BINARY_URL=<direct url to nsigner_static_x86_64>
+
+NSIGNER_VERSION="${NSIGNER_VERSION:-}"
+
+PREFIX_BIN="${HOME}/.local/bin"
+
+log() { printf "\033[1;34m[INFO]\033[0m %s\n" "$*"; }
+warn() { printf "\033[1;33m[WARN]\033[0m %s\n" "$*"; }
+err() { printf "\033[1;31m[ERR ]\033[0m %s\n" "$*"; }
+
+show_help() {
+  cat <<EOF
+Usage: bash install_qube_fips_nsigner.sh [options]
+
+User-only install (Qubes AppVM friendly):
+  - n_signer ${NSIGNER_VERSION}
+  - signer startup helper script
+
+Options:
+  -h, --help      Show this help and exit
+
+Optional env vars:
+  NSIGNER_VERSION=vX.Y.Z         # optional override; default is latest release tag
+  NSIGNER_GITEA_TOKEN=<token>    # required if n_signer release assets are private
+  NSIGNER_BINARY_URL=<direct url to nsigner_static_x86_64>
+
+Install paths:
+  ~/.local/bin/nsigner
+  ~/start_nsigner.sh
+EOF
+}
+
+require_cmd() {
+  command -v "$1" >/dev/null 2>&1 || {
+    err "Missing command: $1"
+    exit 1
+  }
+}
+
+install_runtime_deps() {
+  if command -v apt-get >/dev/null 2>&1; then
+    log "Installing runtime dependencies via apt"
+    sudo apt-get update
+    sudo apt-get install -y ca-certificates curl jq
+  elif command -v dnf >/dev/null 2>&1; then
+    log "Installing runtime dependencies via dnf"
+    sudo dnf install -y ca-certificates curl jq
+  else
+    err "Unsupported distro: need apt-get or dnf to install runtime dependencies"
+    exit 1
+  fi
+}
+
+prepare_dirs() {
+  mkdir -p "${PREFIX_BIN}"
+}
+
+resolve_nsigner_version() {
+  local headers=()
+  local latest_tag=""
+
+  if [[ -n "${NSIGNER_VERSION}" ]]; then
+    return 0
+  fi
+
+  if [[ -n "${NSIGNER_GITEA_TOKEN:-}" ]]; then
+    headers=(-H "Authorization: token ${NSIGNER_GITEA_TOKEN}")
+  fi
+
+  latest_tag="$(curl -fsSL "${headers[@]}" "https://git.laantungir.net/api/v1/repos/laantungir/n_signer/releases" \
+    | jq -r '.[0].tag_name // empty' || true)"
+
+  if [[ -z "${latest_tag}" ]]; then
+    err "Could not resolve latest n_signer release tag from API."
+    err "Set NSIGNER_VERSION explicitly (e.g. NSIGNER_VERSION=v0.0.11)."
+    exit 1
+  fi
+
+  NSIGNER_VERSION="${latest_tag}"
+}
+
+download_nsigner_asset_url() {
+  local headers=()
+  local api_tag_url="https://git.laantungir.net/api/v1/repos/laantungir/n_signer/releases/tags/${NSIGNER_VERSION}"
+
+  if [[ -n "${NSIGNER_GITEA_TOKEN:-}" ]]; then
+    headers=(-H "Authorization: token ${NSIGNER_GITEA_TOKEN}")
+  fi
+
+  curl -fsSL "${headers[@]}" "${api_tag_url}" \
+    | jq -r '.assets[]?.browser_download_url // empty' \
+    | grep -E 'nsigner_static_x86_64$' \
+    | head -n1 || true
+}
+
+install_nsigner() {
+  local release_page=""
+
+  resolve_nsigner_version
+  release_page="https://git.laantungir.net/laantungir/n_signer/releases/tag/${NSIGNER_VERSION}"
+
+  log "Installing n_signer ${NSIGNER_VERSION}"
+  log "Release page: ${release_page}"
+
+  local asset_url="${NSIGNER_BINARY_URL:-}"
+  if [[ -z "${asset_url}" ]]; then
+    asset_url="$(download_nsigner_asset_url)"
+  fi
+
+  if [[ -z "${asset_url}" ]]; then
+    err "Could not find downloadable n_signer x86_64 release binary for ${NSIGNER_VERSION}."
+    err "Provide NSIGNER_BINARY_URL or NSIGNER_GITEA_TOKEN so the release asset can be resolved."
+    exit 1
+  fi
+
+  log "Using n_signer binary URL: ${asset_url}"
+  if [[ -n "${NSIGNER_GITEA_TOKEN:-}" ]]; then
+    curl -fL -H "Authorization: token ${NSIGNER_GITEA_TOKEN}" -o "${PREFIX_BIN}/nsigner" "${asset_url}"
+  else
+    curl -fL -o "${PREFIX_BIN}/nsigner" "${asset_url}"
+  fi
+  chmod 0755 "${PREFIX_BIN}/nsigner"
+  log "Installed ${PREFIX_BIN}/nsigner from release binary"
+}
+
+write_signer_start_script() {
+  local script_path="${HOME}/start_nsigner.sh"
+
+  cat >"${script_path}" <<'EOF'
+#!/usr/bin/env bash
+set -euo pipefail
+
+export PATH="$HOME/.local/bin:$PATH"
+LISTEN_TARGET="${NSIGNER_LISTEN_TARGET:-tcp:[::]:8080}"
+
+echo "=== n_signer startup ==="
+echo "listen target: ${LISTEN_TARGET}"
+
+# Optional: print current FIPS identity info if fipsctl is available.
+if command -v fipsctl >/dev/null 2>&1; then
+  if fipsctl show status >/dev/null 2>&1; then
+    STATUS_JSON="$(fipsctl show status)"
+  elif sudo -n fipsctl show status >/dev/null 2>&1; then
+    STATUS_JSON="$(sudo -n fipsctl show status)"
+  else
+    STATUS_JSON=""
+  fi
+
+  if [[ -n "${STATUS_JSON}" ]]; then
+    FIPS_IPV6="$(printf '%s\n' "${STATUS_JSON}" | sed -n 's/.*"ipv6_addr": "\([^"]*\)".*/\1/p')"
+    FIPS_NPUB="$(printf '%s\n' "${STATUS_JSON}" | sed -n 's/.*"npub": "\([^"]*\)".*/\1/p')"
+    LISTEN_PORT="$(printf '%s\n' "${LISTEN_TARGET}" | sed -n 's/.*:\([0-9][0-9]*\)$/\1/p')"
+    [[ -n "${FIPS_IPV6}" ]] && echo "fips ipv6: ${FIPS_IPV6}"
+    [[ -n "${FIPS_NPUB}" ]] && echo "fips npub: ${FIPS_NPUB}"
+    if [[ -n "${FIPS_NPUB}" && -n "${LISTEN_PORT}" ]]; then
+      echo "fips address: http://${FIPS_NPUB}.fips:${LISTEN_PORT}"
+    fi
+  else
+    echo "fips status: unavailable (run as user in fips group or with sudo)"
+  fi
+fi
+
+echo
+echo "Starting signer..."
+echo "On first remote request, approve in prompt with [y] or [a]."
+exec "$HOME/.local/bin/nsigner" --listen "${LISTEN_TARGET}"
+EOF
+
+  chmod 0755 "${script_path}"
+  log "Wrote ${script_path}"
+}
+
+post_checks() {
+  export PATH="${PREFIX_BIN}:${PATH}"
+
+  log "Running post-install checks"
+  require_cmd nsigner
+  nsigner --version || true
+
+  log "User binaries installed in: ${PREFIX_BIN}"
+  log "If needed, add to shell PATH: export PATH=\"${PREFIX_BIN}:\$PATH\""
+}
+
+main() {
+  if [[ "${1:-}" == "-h" || "${1:-}" == "--help" ]]; then
+    show_help
+    exit 0
+  fi
+
+  if [[ $# -gt 0 ]]; then
+    err "Unknown option: $1"
+    show_help
+    exit 1
+  fi
+
+  install_runtime_deps
+  prepare_dirs
+  install_nsigner
+  write_signer_start_script
+  post_checks
+
+  log "Completed user-only install of n_signer"
+  log "Start signer with: ~/start_nsigner.sh"
+}
+
+main "$@"

packaging/qubes/install-policy.sh

@@ -0,0 +1,17 @@
+#!/bin/sh
+set -eu
+
+POLICY_SRC="packaging/qubes/policy.d/40-nsigner.policy"
+POLICY_DST="/etc/qubes/policy.d/40-nsigner.policy"
+
+if [ ! -f "$POLICY_SRC" ]; then
+    echo "Missing policy source: $POLICY_SRC" >&2
+    exit 1
+fi
+
+install -m 0644 "$POLICY_SRC" "$POLICY_DST"
+
+echo "Installed qrexec policy to $POLICY_DST"
+echo "Tag your signer qube in dom0, for example:"
+echo "  qvm-tags nsigner-vault add nsigner-signer"
+echo "Then reload policy per your Qubes OS version procedures."

packaging/qubes/install-service.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+set -eu
+
+SERVICE_SRC="packaging/qubes/rpc/qubes.NsignerRpc"
+SERVICE_DST="/etc/qubes-rpc/qubes.NsignerRpc"
+
+if [ ! -f "$SERVICE_SRC" ]; then
+    echo "Missing service source: $SERVICE_SRC" >&2
+    exit 1
+fi
+
+install -m 0755 "$SERVICE_SRC" "$SERVICE_DST"
+
+echo "Installed qrexec service to $SERVICE_DST"
+echo "Executable bit set via install -m 0755."

packaging/qubes/policy.d/40-nsigner.policy

@@ -0,0 +1,5 @@
+# Qubes OS qrexec policy for nsigner
+# Syntax: service +argument source target action
+# Allow specific qubes to reach the signer qube with user confirmation
+qubes.NsignerRpc * @anyvm @tag:nsigner-signer ask default_target=nsigner-vault
+qubes.NsignerRpc * @anyvm @anyvm deny

packaging/qubes/rpc/qubes.NsignerRpc

@@ -0,0 +1,2 @@
+#!/bin/sh
+exec /usr/local/bin/nsigner --listen qrexec

plans/deny_by_default_approvals.md

@@ -0,0 +1,357 @@
+# Plan: Deny-by-default approvals + on-demand role derivation
+
+Status: **implemented**
+
+This plan replaces several entangled mechanisms (same-uid auto-allow, role pre-registration as a hard rule, global `[a]` flag) with a single, coherent approval model. It also addresses the `n_OS_tr` system-services-at-boot scenario.
+
+If implemented, this plan supersedes:
+
+- The same-uid auto-allow rule in [`policy_init_default()`](../src/policy.c:551).
+- The "role_path / nostr_index must be pre-registered" rule recorded in [`plans/nsigner.md:159`](nsigner.md:159) (the rule is *narrowed*, not removed — see §5).
+- The global `g_prompt_always_allow` flag in [`src/server.c:469`](../src/server.c:469) as the meaning of prompt-`[a]`. The running-TUI `[a]` hotkey is unaffected (or removed; see §11).
+
+---
+
+## 1. Goals
+
+1. **Deny-by-default.** No client can sign or get a public key without an explicit human approval at the terminal **or** an explicit pre-approval declared at startup.
+2. **One approval mechanism.** Both the runtime prompt (human approves a request) and the boot-time pre-approval (OS-level config) populate the **same** in-memory policy table. There is exactly one path through the dispatcher that determines whether to sign.
+3. **On-demand role creation.** When a request specifies an unregistered `nostr_index`, the prompt path may auto-derive a fresh role at that index *only after* the human (or a startup pre-approval) consents. Pre-registration of `role_path` keys remains required.
+4. **Boot-time ergonomics for `n_OS_tr`.** OS-level system services that need keys at boot can be pre-approved by the OS distribution via CLI flags, with no prompts and no on-disk runtime config files.
+5. **Auditable approval source.** The activity log distinguishes between approvals granted at runtime by the user, approvals loaded from startup pre-approvals, and approvals already in place from prior session activity.
+
+## 2. Non-goals
+
+- This plan does **not** add per-verb scoping at the prompt. `[a]` means "this caller may use this role for all verbs the role's purpose/curve permits." Per-verb scoping is a future iteration.
+- This plan does **not** add persistent (across-restart) policy storage. Approvals still vanish on process exit.
+- This plan does **not** introduce capability tokens or any new authentication primitive. Identity remains transport-derived.
+- This plan does **not** change the wire protocol. Clients see the same JSON-RPC request/response shape.
+
+## 3. The new model in one paragraph
+
+The signer maintains an in-memory policy table whose entries are tuples of `(caller_id, role, prompt_mode)`. At startup, the table is empty except for entries declared via `--preapprove` CLI flags (set by `n_OS_tr` system unit files for boot-required services). Every request without a matching policy entry triggers an interactive prompt at the terminal. If the user picks `[a]`, a new policy entry for `(this caller, this role)` is appended to the table and any future request matching that tuple is served silently. If the request specifies an unregistered `nostr_index`, the consent path also derives a fresh role at that index. The `*` catch-all is `PROMPT_DENY` for any caller that hasn't been explicitly added.
+
+## 4. Concept renaming and positioning
+
+The user-facing language collapses to three concepts:
+
+| User-facing term | Internal mapping |
+|---|---|
+| **Identity** | `caller_identity_t` (uid, qubes vm name, tcp peer, etc.) |
+| **Index / Path** | `nostr_index` shorthand or full `role_path` for advanced use |
+| **Approval** | A policy table entry with `prompt_mode = PROMPT_NEVER` |
+
+The word **role** is retained internally (the role table, the [`role_entry_t`](../src/role_table.c:103) struct, derivation paths) but de-emphasized in user-facing prompts and docs. A user reading a prompt sees:
+
+```
+Approval required
+caller:  qubes:nostr-relay
+verb:    sign_event
+index:   nostr_index=0    (resolves to the default identity)
+```
+
+instead of `role: main`. Internally the resolved role is still recorded for audit.
+
+## 5. The narrowed pre-registration rule
+
+The original rule was: **all** selectors must resolve to a pre-registered role.
+
+The new rule is:
+
+> Pre-registration is required for **`role_path`** selectors. For **`nostr_index`** selectors, an unregistered index is a valid prompt trigger, and the role for that index is derived on the fly **after** explicit consent (prompt or `--preapprove`).
+
+Rationale:
+
+- `nostr_index` paths follow a fixed scheme (`m/44'/1237'/<n>'/0/0`) with locked purpose (`nostr`) and curve (`secp256k1`). Auto-derivation cannot accidentally produce a key that mixes purposes. The risk is solely "this is a fresh nostr identity"; the human at the prompt can answer that.
+- `role_path` is free-form and can address any BIP-32 path, including paths that overlap with bitcoin/SSH/age domains. Auto-derivation here would let a malicious or buggy client coerce the signer into producing keys whose purpose the human can't easily verify. We keep that locked.
+- This narrowing is the smallest crack we can open in the original rule that still solves the user's `nostr_index: 1` use case.
+
+[`plans/nsigner.md:159`](nsigner.md:159) ("`role_path` must be pre-registered") remains true. The `nostr_index` clause becomes new and explicit.
+
+## 6. The four pieces of work
+
+### Piece A — Deny-by-default policy
+
+#### A.1 Default policy table
+
+[`policy_init_default()`](../src/policy.c:551) currently inserts two entries:
+
+1. `caller = "uid:<owner>"` → `PROMPT_NEVER` (auto-allow same-uid)
+2. `caller = "*"` → `PROMPT_DENY`
+
+The new default inserts only:
+
+1. `caller = "*"` → `PROMPT_PROMPT`
+
+There is no same-uid special case. Even the user's own client triggers a prompt the first time it connects.
+
+If `--preapprove` flags were given at startup, those entries are appended **before** the catch-all `*` so they win first-match. See §C.
+
+#### A.2 Removal of `g_prompt_always_allow` as a *prompt outcome*
+
+The flag is currently set to 1 by both:
+
+- The interactive prompt's `[a]` outcome ([`src/server.c:684`](../src/server.c:684))
+- The running-TUI `[a]` hotkey ([`src/main.c:974`](../src/main.c:974), [`src/main.c:1239`](../src/main.c:1239))
+
+The prompt's `[a]` no longer flips the flag. Instead it appends a per-`(caller, role)` policy entry. See §B.
+
+The running-TUI `[a]` hotkey can either be:
+
+- Removed, since it is now redundant with explicit per-caller entries, **or**
+- Retained as a debugging/panic mode under a non-default name, e.g. `[A]` (capital) for "auto-approve everything regardless of caller; for development only."
+
+The plan recommends retaining it as a deliberately ugly, capital-letter hotkey so its destructive scope is visible. Default-off; activates only on explicit press.
+
+#### A.3 Wire-level effect
+
+A previously-unknown caller making a first request observes:
+
+1. Length-prefixed request lands.
+2. Selector resolves (or fails — see §B).
+3. Policy lookup returns `POLICY_PROMPT` because no matching entry exists.
+4. Server blocks the request, prints the prompt to the controlling terminal, waits for keystroke.
+5. On `[a]`, server appends `(caller, role) → PROMPT_NEVER` and serves the request.
+6. On `[y]`, server serves once without appending.
+7. On `[n]`, server returns `policy_denied` without appending.
+8. On EOF / non-interactive: server returns `policy_denied`. There is no implicit allow path for non-interactive sessions; OS distributions must use `--preapprove`.
+
+### Piece B — On-demand role derivation at the prompt
+
+#### B.1 Failure path today
+
+When `selector_resolve()` returns `SELECTOR_ERR_NOT_FOUND` for an unregistered `nostr_index`, the request currently dies in the dispatcher with `unknown_role` (error 1002). The user observes nothing in the terminal.
+
+#### B.2 New failure path
+
+The server's request-handling loop checks selector resolution **before** invoking the dispatcher. The new control flow:
+
+```
+1. Receive request, parse method + selector.
+2. Try selector_resolve():
+     a. SELECTOR_OK -> proceed to step 3 with the resolved role.
+     b. SELECTOR_ERR_NOT_FOUND on nostr_index -> proceed to step 3 with
+        a PENDING_DERIVATION marker holding the requested index.
+     c. SELECTOR_ERR_NOT_FOUND on role_path -> reject with unknown_role.
+     d. SELECTOR_ERR_AMBIGUOUS -> reject with ambiguous_role_selector.
+     e. SELECTOR_ERR_NO_DEFAULT -> reject with internal_error
+        (this should never happen if main role is always present).
+3. Determine policy: ALLOW / DENY / PROMPT.
+   - For PENDING_DERIVATION cases, the prompt displays the requested
+     index and clearly states "this will create a new identity."
+4. On PROMPT, ask human; on [a] or [y], proceed; on [n], reject.
+5. On approval to proceed:
+     a. If PENDING_DERIVATION, register a role for that index in the
+        role_table now. Synthesize a name like nostr_idx_7. Trigger
+        key derivation for the new role.
+     b. If [a] (not [y]), append a session policy entry for
+        (caller, resolved-role-name) with PROMPT_NEVER.
+6. Invoke the dispatcher with the resolved role.
+7. Send response, append activity log line including approval source.
+```
+
+#### B.3 Auto-registered role naming
+
+A role auto-registered for `nostr_index = N` is named `nostr_idx_N` by the signer.
+
+- Predictable, so humans reading the activity log can correlate.
+- Will not collide with the built-in `main` (which is `nostr_idx_0` by index but `main` by name; the role table allows lookups by either).
+- Does not require user input at the prompt. Naming UX is a future iteration.
+
+#### B.4 Role-table sizing
+
+[`ROLE_TABLE_MAX_ENTRIES`](../src/role_table.c) is currently small. With on-demand derivation a single session might accumulate dozens of `nostr_idx_*` entries. Bump the constant to an explicit budget (suggest 256). On overflow, return a clear error like `role_table_full` rather than crashing.
+
+#### B.5 Persistence
+
+Same as everything else in n_signer: derived roles vanish on process exit. The next session re-derives `nostr_idx_7` from the same mnemonic, getting the same key. This is normal and intentional.
+
+### Piece C — `--preapprove` CLI flag
+
+#### C.1 Flag syntax
+
+```
+--preapprove <SPEC>
+```
+
+`SPEC` is a comma-separated list of `key=value` pairs. Required keys:
+
+- `caller=<id>` — exact caller identity to match. Format depends on transport:
+  - `uid:1000`
+  - `qubes:work-vm`
+  - `tcp:[fdb8::1]:0` (port 0 means "any port")
+  - `qubes:*` is **not** supported. Wildcards are intentionally restricted to the catch-all entry only.
+- One of:
+  - `role=<name>` — match the role by name. Useful when the OS knows it wants `main`.
+  - `nostr_index=<n>` — match by index. Equivalent to `role=nostr_idx_<n>` after auto-derivation.
+
+Optional keys (deferred for now, but reserved):
+
+- `verbs=<list>` — comma-separated verb list. Default is `*`.
+- `purposes=<list>` — comma-separated purpose list. Default is `*`.
+
+Multiple `--preapprove` flags are allowed; each becomes a separate policy entry.
+
+#### C.2 Example: `n_OS_tr` boot
+
+`n_OS_tr`'s systemd unit file:
+
+```ini
+[Service]
+ExecStart=/usr/bin/n_signer \
+  --preapprove caller=qubes:nostr-relay,role=main \
+  --preapprove caller=qubes:dm-handler,nostr_index=1 \
+  --preapprove caller=qubes:contacts,nostr_index=2 \
+  --preapprove caller=qubes:zaps,nostr_index=3
+```
+
+At startup, n_signer:
+
+1. Parses each `--preapprove` flag into a `policy_entry_t` with `prompt = PROMPT_NEVER`.
+2. For each entry that references an unregistered `nostr_index`, auto-derives the role *immediately at startup* (not lazily — we want all key derivation to happen before services start signaling readiness).
+3. Inserts each policy entry into the table **before** the catch-all `*` deny.
+4. Logs each pre-approval to stderr at boot so the systemd unit's journal records what was preapproved.
+
+When `qubes:nostr-relay` connects and asks for `sign_event` against `role=main`, `policy_check()` matches the preapprove entry, returns `POLICY_ALLOW`, and the request is served with no prompt.
+
+When some other caller (say, a misconfigured systemd service) connects, the catch-all matches and the request is denied (or prompts, in interactive mode — see §C.4).
+
+#### C.3 What `--preapprove` cannot do
+
+- **Cannot deny.** Deny entries can only come from defaults or the prompt's `[n]` (if we ever add caller-deny). Pre-approve only widens.
+- **Cannot match wildcards on caller.** Each entry must specify exactly one caller_id. The OS distribution is responsible for knowing exactly who its services are.
+- **Cannot bypass purpose/curve enforcement.** A pre-approval to use `role=main` for `verb=sign_btc_tx` (a hypothetical bitcoin verb) still fails enforcement because `main`'s purpose is `nostr`. The pre-approval grants access to the role; enforcement still gates the verb.
+
+#### C.4 Interaction with interactive mode
+
+The same binary supports both:
+
+- `n_signer` with no `--preapprove` flags → pure deny-by-default, every first request prompts.
+- `n_signer --preapprove ...` → starts with the listed entries already in the policy table.
+
+Both modes use exactly the same code path. There is no separate "system mode" toggle.
+
+#### C.5 Auditability
+
+When a pre-approval matches, the activity log line includes the source:
+
+```
+qubes:nostr-relay  sign_event(role=main)  ALLOWED:preapprove
+```
+
+So an operator reviewing the log can tell which decisions came from boot config vs. runtime user approvals.
+
+#### C.6 Validation
+
+Bad `--preapprove` syntax fails fast at startup with a clear error message. n_signer refuses to start. This avoids the "I thought I configured this but typoed it" silent-degrade problem.
+
+### Piece D — Audit-log labeling of approval source
+
+#### D.1 The four label values
+
+| Label | Meaning |
+|---|---|
+| `:preapprove` | Matched a policy entry installed via `--preapprove` at startup. |
+| `:session-grant` | Matched a policy entry created earlier in this session by a prompt `[a]`. |
+| `:prompt` | Just-now approved by the user pressing `[y]` or `[a]` at the prompt. |
+| `:auto-allow` | Matched the running-TUI `[a]` panic mode (if retained). |
+
+A line in the activity log under the new model:
+
+```
+[2026-05-04 16:03:11] qubes:nostr-relay  sign_event(role=main)  ALLOWED:preapprove
+[2026-05-04 16:03:14] uid:1000           sign_event(role=main)  ALLOWED:session-grant
+[2026-05-04 16:03:18] tcp:[::1]:54122    get_public_key(role=nostr_idx_7) ALLOWED:prompt
+[2026-05-04 16:03:21] uid:1001           sign_event(role=main)  DENIED:no-match
+```
+
+#### D.2 Implementation
+
+The label is a small enum threaded from `policy_check()` (which returns the matching entry's source tag) and from `prompt_for_policy_decision()` (which returns `:prompt`). `server_handle_one()` includes the label in the activity-log line.
+
+#### D.3 Visibility
+
+The label appears in:
+
+- The TUI's running activity buffer.
+- The structured activity event passed to the `server_activity_cb` callback (so external observers — e.g. a future syslog feeder — can also see the source).
+
+#### D.4 No on-disk persistence
+
+The activity buffer remains in-memory only. If `n_OS_tr` wants persistent audit, it forwards the activity callback to its own logging subsystem outside of n_signer's process.
+
+## 7. Code change inventory
+
+| Module | Change |
+|---|---|
+| [`src/policy.c`](../src/policy.c) | `policy_init_default()` collapses to one entry. `policy_check()` extends to return the matching entry's source label. New helper `policy_table_add_at_position()` to insert before the catch-all. |
+| [`src/server.c`](../src/server.c) | `prompt_for_policy_decision()` rewritten: appends a policy entry on `[a]`, no longer flips the global flag. New pre-derivation control flow in `server_handle_one()`. New CLI parser for `--preapprove`. |
+| [`src/role_table.c`](../src/role_table.c) | Bump `ROLE_TABLE_MAX_ENTRIES` to 256. New `role_table_register_nostr_index(int n)` helper that creates a `nostr_idx_<n>` entry and triggers derivation. |
+| [`src/key_store.c`](../src/key_store.c) | Add a one-role derivation path so newly-registered roles can be derived without re-deriving the whole table. |
+| [`src/dispatcher.c`](../src/dispatcher.c) | No semantic change — dispatcher continues to assume the role exists. The server makes that true before invoking. |
+| [`src/main.c`](../src/main.c) | CLI parsing for `--preapprove`. Remove or restrict the running-TUI `[a]` hotkey. Log preapproves to stderr at boot. |
+| [`tests/test_policy.c`](../tests/test_policy.c) | New tests: deny-by-default, prompt-`[a]` appends entry, preapprove flag parsing, source-label propagation. |
+| [`tests/test_dispatcher.c`](../tests/test_dispatcher.c) | New tests: unregistered nostr_index path with consent-required gating. |
+| [`tests/test_integration.c`](../tests/test_integration.c) | New scenario: `--preapprove` allows scripted client; without it, scripted client gets denied. |
+| [`documents/SECURITY.md`](../documents/SECURITY.md) | Rewritten in identity / index / approval terms (separate task after this plan ships). |
+| [`documents/CLIENT_IMPLEMENTATION.md`](../documents/CLIENT_IMPLEMENTATION.md) | Add a note about possible `policy_denied` on first contact in interactive mode; pointer to `--preapprove` for system services. |
+| [`plans/nsigner.md`](nsigner.md) | Decisions log entry referencing this plan. The `role_path` pre-registration rule remains; the `nostr_index` clause becomes new. |
+
+## 8. Test plan
+
+Tests must cover at minimum:
+
+1. **Default deny.** A startup with no `--preapprove` flags receives a request from any caller and (in non-interactive mode) returns `policy_denied`.
+2. **Prompt `[a]` appends entry.** Inject a non-interactive prompt-default of `ALLOW`, observe a policy entry added, verify a second matching request is served without re-prompting.
+3. **Prompt `[y]` does not append entry.** Same fixture, second request still triggers the prompt path.
+4. **`--preapprove` with `role=main`.** Request from named caller succeeds without prompt; request from any other caller is denied.
+5. **`--preapprove` with `nostr_index=N` for unregistered N.** Role is auto-derived at startup; request succeeds; activity log shows `:preapprove`.
+6. **`--preapprove` cannot bypass enforcement.** Pre-approve `(caller=X, role=main)` and request a verb that violates purpose/curve. Response is `purpose_mismatch` or `curve_mismatch`.
+7. **Unknown `role_path` still rejected.** Even with consent, an unregistered `role_path` returns `unknown_role`. (The narrowing is `nostr_index`-only.)
+8. **Audit-log labels.** Each path produces the expected source tag.
+9. **Multi-instance isolation.** Two n_signers with different `--preapprove` lists serve different requests; cross-instance requests are denied as expected.
+10. **Role table overflow.** Force more than `ROLE_TABLE_MAX_ENTRIES` derivations and observe `role_table_full` instead of corruption.
+
+## 9. Backwards-compatibility implications
+
+- **Existing scripts that rely on same-uid auto-allow break.** They now hit the prompt (interactive) or get denied (non-interactive). Migration path: add `--preapprove caller=uid:1000,role=main` to the startup invocation. We document this prominently.
+- **Interactive desktop users see a prompt the first time their client connects, where today they don't.** This is the intended behavior change. We document it in the README.
+- **Wire protocol unchanged.** No client-side changes required.
+- **Existing `[a]` running-TUI hotkey may change semantics or disappear.** This is the most disruptive UI change for someone who actually uses the panic-allow today. Document the change in the release notes.
+
+## 10. Rollout staging
+
+This is too much to land in one commit. Suggested order:
+
+1. **Stage 1 — deny-by-default + prompt `[a]` appends entry.** Removes the same-uid auto-allow, makes the prompt the source of session-grants. No CLI flag yet. Headless scripts break; we accept that for now and document the workaround as "use stage 2."
+2. **Stage 2 — `--preapprove` CLI flag.** Restores headless ergonomics for OS distributions like `n_OS_tr`.
+3. **Stage 3 — on-demand role derivation at the prompt.** Closes the user-visible `(unknown)` failure mode.
+4. **Stage 4 — audit-log labels and structured activity output.** Forensics + observability.
+5. **Stage 5 — `documents/SECURITY.md` rewrite.** After the code is settled.
+
+Each stage is a self-contained release.
+
+## 11. Open decisions to confirm before coding
+
+- **Q1.** Keep the running-TUI `[a]` hotkey as a panic-allow under a different visual treatment, or remove it entirely? Plan recommends keep, capitalized, default-off.
+- **Q2.** Is `nostr_idx_<n>` an acceptable auto-naming convention, or do we want to ask the user for a name in the prompt? Plan recommends auto-name now, prompt-name later as iteration.
+- **Q3.** Should the prompt's "this will create a new identity" warning differ visually from a normal approval prompt? Plan recommends a clearly distinct extra line in the prompt body.
+- **Q4.** What is the ceiling for `ROLE_TABLE_MAX_ENTRIES`? Plan recommends 256 with a fail-loud overflow.
+- **Q5.** Do we want a TUI panel showing the active session approvals (helpful for the user to see what they've granted)? Plan recommends yes, smallest possible: caller + role + source label. Could be deferred to a later stage.
+
+## 12. After this plan lands: deferred work
+
+- Per-verb scoping at the prompt (the user wants `[a]` to mean "all verbs for this role" but a future `[c]` to mean "let me pick"). Deferred per the user's instruction.
+- Approval revocation hotkeys (`[k]` to clear all session-grants, `[K]` to clear one).
+- Approvals visible-and-editable as a TUI panel.
+- Persistent (cross-restart) approvals — explicitly out of scope; n_signer remains memory-only.
+- `role_path` auto-derivation under prompt — explicitly out of scope; the security argument in §5 stands.
+- Capability tokens for cross-machine transports (FIPS, USB serial) — separate plan, separate threat model.
+
+## 13. References
+
+- [`README.md`](../README.md) — authoritative behavior spec.
+- [`plans/nsigner.md`](nsigner.md) — root design plan; pre-registration rule at line 159.
+- [`documents/CLIENT_IMPLEMENTATION.md`](../documents/CLIENT_IMPLEMENTATION.md) — wire contract.
+- [`documents/SECURITY.md`](../documents/SECURITY.md) — security model document; will be rewritten when this plan lands.
+- [`src/policy.c`](../src/policy.c), [`src/server.c`](../src/server.c), [`src/dispatcher.c`](../src/dispatcher.c), [`src/role_table.c`](../src/role_table.c), [`src/selector.c`](../src/selector.c) — code that changes.

plans/nsigner.md

@@ -68,8 +68,82 @@ This plan adopts a single foreground program model instead of a daemon model to
 
 - Single test that launches the program (with mnemonic piped via stdin for automation), sends requests via client subcommand, verifies responses
 
+### Phase G2 — Mnemonic generation at startup
+
+Goal: let the user generate a brand-new BIP-39 mnemonic at startup instead of typing an existing one. The generated mnemonic is shown once and used for the session; no confirmation step is required.
+
+Steps:
+
+- Extend startup TUI: prompt user with `[E]nter existing mnemonic` / `[G]enerate new mnemonic` (default `E`).
+- New module function `mnemonic_generate(int word_count, char *out, size_t out_len)` in [`src/mnemonic.c`](../src/mnemonic.c:1):
+  - `getrandom(2)` for entropy (16 bytes for 12 words, 32 bytes for 24).
+  - Compute SHA-256 of entropy → first `entropy_bits / 32` checksum bits.
+  - Concatenate entropy + checksum bits → slice into 11-bit groups.
+  - Look up each group in the BIP-39 English wordlist → space-separated mnemonic.
+  - Zeroize the entropy buffer immediately after use.
+- Default word count: 12 (no extra prompt).
+- TUI display:
+  - Numbered word list (1..12).
+  - Loud warning: "WRITE THIS DOWN — IT WILL NOT BE SHOWN AGAIN."
+  - "Press any key to continue" — explicit no-confirmation policy per spec.
+- After display, the in-memory mnemonic is fed straight into the existing seed-derivation path; no separate buffer or persistence layer is introduced.
+- Tests in [`tests/test_mnemonic.c`](../tests/test_mnemonic.c:1):
+  - `mnemonic_generate(12)` returns 12 valid BIP-39 English words.
+  - `mnemonic_generate(24)` returns 24 valid BIP-39 English words.
+  - Output validates against the existing `mnemonic_validate` function (round-trip).
+  - Two consecutive calls return different mnemonics with overwhelming probability.
+
+### Phase H — Multi-instance signer naming (random BIP-39)
+
+Goal: allow multiple `nsigner` processes to coexist on one host by giving each instance a unique, human-readable abstract socket name.
+
+Approach: at startup, pick two random BIP-39 English words and bind to `@nsigner_<word1>_<word2>` (e.g. `@nsigner_hairy_dog`).
+
+Steps:
+
+- New module `src/socket_name.{h,c}`
+  - `int socket_name_random(char *out, size_t out_len);`
+  - Calls `getrandom(2)` for 3 bytes (24 bits), splits into two 11-bit indices, looks up words from the BIP-39 English wordlist, formats `nsigner_<w1>_<w2>`.
+- BIP-39 English wordlist
+  - Use the wordlist exposed by `nostr_core_lib` (no vendored `bip39_english.c` in this repo).
+- `src/server.c` bind logic
+  - Accept the resolved name from caller.
+  - Bind once. On `EADDRINUSE` and no `--socket-name` override, regenerate a fresh random name and retry up to 8 times. With override, fail immediately and report the override conflict.
+- `src/main.c` integration
+  - Resolve name precedence: `--socket-name` (explicit) > random pick.
+  - After mnemonic acceptance, derive/pick the name and pass it to the server.
+  - TUI startup banner shows the friendly name and the socket address prominently so the user knows what to point clients at.
+- `nsigner list` subcommand
+  - Reads `/proc/net/unix`, filters entries whose path starts with `\0nsigner_`, prints them as `@nsigner_<w1>_<w2>` along with inode/state if useful.
+  - No protocol change; purely a discovery helper.
+- Tests
+  - `tests/test_socket_name.c` — format check, both indices land in `[0, 2048)`, two consecutive calls produce different names with overwhelming probability.
+  - `tests/test_integration.c` — launch with explicit `--socket-name nsigner_test_run` so the integration test is deterministic and isolated.
+
+Privacy/UX notes:
+
+- Random names leak nothing about the seed; the trade-off is the user must read the banner each launch to know which socket to address.
+- ~4.2M combinations × small concurrent process count = collision essentially never observed in practice; retry path exists for correctness.
+- Behavior of `--socket-name` is unchanged; it remains the deterministic override for scripts and tests.
+
 ## 4. Decisions log
 
+### 2026-05-02 — Mnemonic generation at startup
+
+1. Startup offers `[E]nter` or `[G]enerate` choice; default is `E`.
+2. Generated mnemonic uses `getrandom(2)` + BIP-39 English wordlist, default 12 words.
+3. Mnemonic is displayed exactly once with a "write this down" warning.
+4. **No confirmation step** — user is trusted to copy the words; we proceed straight to session use.
+5. The in-memory lifecycle is identical to a typed mnemonic (same secure buffer, same crash-wipe semantics).
+
+### 2026-05-02 — Random per-launch signer naming
+
+1. Multiple `nsigner` instances can run concurrently on one host.
+2. Default socket name is `@nsigner_<bip39_word1>_<bip39_word2>` chosen randomly at each launch.
+3. `--socket-name <name>` overrides the random pick for tests and scripted usage (aliases: `--name`, `-n`).
+4. `nsigner list` enumerates running signers via `/proc/net/unix` filtered on `nsigner_` prefix.
+5. Random naming was chosen over deterministic-from-mnemonic for v1 to avoid leaking any seed-derived identifier in the abstract namespace; deterministic naming may be revisited later.
+
 ### 2026-05-02 — Program not daemon pivot
 
 1. Single foreground process replaces daemon + TUI + client multi-binary model
@@ -89,16 +163,130 @@ This plan adopts a single foreground program model instead of a daemon model to
 
 ## 5. Open questions
 
-- Automated test strategy for interactive TUI (stdin pipe? expect-style? separate test mode flag?)
-- ESP32 transport shim interface definition
-- NIP-46 relay transport integration timeline
-- Role enrollment UX: how many questions at startup vs. "just use main = index 0"?
-- Lock-without-exit: needed? Or is quit-and-relaunch sufficient?
+- ESP32 transport shim interface definition and frame format details.
+- NIP-46 relay transport integration timeline.
+- Role enrollment UX depth at startup vs. minimal defaults.
+- Optional policy granularity beyond same-uid + interactive prompt (e.g. per-verb/per-role session rules).
 
 ## 6. Immediate next work
 
-- Execute Phase A (cleanup)
-- Execute Phase B (server module)
-- Execute Phase C (unified main)
-- Execute Phase D (policy simplification)
-- Execute Phase E (integration test)
+- Add regression tests for prompt-overlay behavior and running-phase hotkeys.
+- Expand integration coverage for NIP-04/NIP-44 edge cases and negative-path errors.
+- Document and test static artifact size budgets across targets.
+- Define MCU transport adapter contract to prepare desktop/firmware parity.
+
+## 7. Transport expansion roadmap
+
+Goal: keep one signer core, swap transports underneath without touching dispatcher, policy, or role layers. The wire contract in [`CLIENT_IMPLEMENTATION.md`](../CLIENT_IMPLEMENTATION.md) (4-byte length-prefixed JSON-RPC) stays identical across every transport; only listener and `caller_identity_t` change.
+
+### 7.0 Prerequisite — transport abstraction (Phase T0)
+
+Before adding any new transport, factor a small adapter contract out of [`src/server.c`](../src/server.c) and [`src/main.c`](../src/main.c).
+
+- New header `src/transport.h` declaring an opaque `nsigner_transport_t` with:
+  - `accept(listener) -> connection`
+  - `recv_frame(connection) -> bytes`
+  - `send_frame(connection, bytes)`
+  - `peer_identity(connection) -> caller_identity_t`
+  - `close(connection)` / `shutdown(listener)`
+- Generalize `caller_identity_t` to a tagged union of:
+  - `unix_peer { uid, pid, comm }` (current behavior)
+  - `qubes { source_qube_name }`
+  - `tcp_local { addr }`
+  - `tcp_remote { addr, authenticated_pubkey }`
+  - `fips { peer_npub }`
+  - `usb_serial { device_path, asserted_caller }`
+- Move `recv_framed` / `send_framed` from `server.c` and `main.c` into a single shared `transport_frame.c` so client and server share one framing implementation.
+- Server main loop becomes transport-agnostic (`while accept; recv; dispatch; send`).
+- Tests: extend [`tests/test_integration.c`](../tests/test_integration.c) with a transport-loopback fake to validate the abstraction without binding any real socket.
+
+This refactor is purely internal — no observable change.
+
+### 7.1 Phase T1 — Qubes OS qrexec transport
+
+Use Qubes' native inter-qube primitive instead of inventing one.
+
+- Add a qrexec service script (e.g. `qubes.NsignerRpc`) that execs `nsigner` in a "stdio transport" mode where stdin/stdout carry the existing length-prefixed frame protocol.
+- New CLI: `nsigner --listen stdio` (and `nsigner --listen qrexec`, behaving identically; `qrexec` value is for documentation/intent).
+- Caller identity comes from qrexec environment (`QREXEC_REMOTE_DOMAIN`) and is mapped to `caller_identity_t.kind=qubes`.
+- Reference policy file under `packaging/qubes/policy.d/40-nsigner.policy` showing `ask` / `allow` per source qube.
+- No new attack surface inside nsigner: dom0 enforces who can even invoke the service.
+- Tests: a unit test that injects fake qrexec env vars and a stdio framing harness; an integration script that documents end-to-end install in a Qubes VM (manual, not in CI).
+- Docs: add a "Qubes deployment" section to [`README.md`](../README.md) and to [`CLIENT_IMPLEMENTATION.md`](../CLIENT_IMPLEMENTATION.md).
+
+### 7.2 Phase T2 — TCP transport
+
+Smallest IP-based step; on-ramp for non-Linux clients and for FIPS later.
+
+- New CLI: `nsigner --listen tcp:HOST:PORT` (IPv4 literal) or `nsigner --listen tcp:[IPv6]:PORT`.
+- Current behavior: accepts operator-selected local/remote bind addresses (including `[::]` and `fd..`), pending later transport hardening.
+- Caller identity for TCP: endpoint address/port in caller descriptor. Approval prompt still mandatory.
+- `nsigner list` extended to enumerate active TCP listeners (from internal registry; not from `/proc/net/tcp`).
+- Same framing as AF_UNIX path; no protocol changes.
+- Tests: integration coverage that spawns a child signer with `--listen tcp:127.0.0.1:0` (and one IPv6 case), captures the bound port, runs the same NIP-04/NIP-44/sign_event matrix as AF_UNIX.
+- Docs: extend [`documents/CLIENT_IMPLEMENTATION.md`](../documents/CLIENT_IMPLEMENTATION.md) section 2 with `tcp:` discovery rules and section 3 confirming framing parity.
+
+Implementation checklist (Tier-1 delivery):
+
+- [x] Parse `--listen tcp:HOST:PORT` in [`src/main.c`](../src/main.c).
+- [x] Parse and validate literal IPv4/IPv6 listen targets in [`src/server.c`](../src/server.c).
+- [x] Bind/listen non-blocking TCP sockets and run server loop without TUI dependence.
+- [x] Keep existing framed JSON-RPC protocol unchanged via shared [`src/transport_frame.c`](../src/transport_frame.c).
+- [ ] Add integration test coverage for `tcp:127.0.0.1:PORT` request flow.
+
+### 7.3 Phase T3 — TCP remote with TLS + caller-pubkey auth
+
+Only after T2 is solid.
+
+- New CLI: `nsigner --listen tcp:0.0.0.0:PORT --allow-remote --tls-cert <pem> --tls-key <pem>`.
+- Mandatory: TLS for any non-loopback bind. Refuse to start otherwise.
+- Caller authentication: client must sign a per-connection challenge with its declared npub (Schnorr/secp256k1) before any signer verb is dispatched. Identity becomes `tcp_remote { addr, authenticated_pubkey }`.
+- Failure modes: `transport_tls_required`, `caller_auth_failed`, `caller_auth_timeout` — all surfaced with new error names in dispatcher and documented in [`CLIENT_IMPLEMENTATION.md`](../CLIENT_IMPLEMENTATION.md).
+- Approval prompt now displays `caller=npub:abcd…wxyz` instead of `uid:1000`.
+- Tests: integration test that exercises happy path, wrong-pubkey, replayed-challenge, expired-challenge.
+- Docs: dedicated "Remote TCP deployment" section in `README.md` with strong "do not expose to the public internet without firewalling" warning.
+
+### 7.4 Phase T4 — FIPS substrate integration
+
+FIPS is a *substrate* for an existing TCP listener, not a new transport in nsigner code.
+
+- Deployment topology: nsigner binds a chosen TCP endpoint inside the FIPS network namespace (or on a host where `fips0` is up); peers reach it via `fd00::/8` IPv6 derived from the signer's npub.
+- Optional `caller_kind=fips` enrichment: a small sidecar query (`fipsctl show sessions` style) maps the connecting IPv6 address to a peer npub and feeds it into `caller_identity_t.fips { peer_npub }`. If unavailable, fall back to `tcp_remote` identity.
+- nsigner does not embed FIPS, does not depend on libfips, and does not require Rust.
+- New optional flag: `--peer-id-source fips:/var/run/fips/fips.sock` (path/method TBD per FIPS API).
+- Tests: a Docker-compose fixture borrowed from `resources/fips/testing/` that boots two FIPS nodes, runs nsigner on one, runs a Python client (per snippet in [`documents/CLIENT_IMPLEMENTATION.md`](../documents/CLIENT_IMPLEMENTATION.md)) on the other, and exercises the same verb matrix.
+- Docs: new [`documents/FIPS_DEPLOYMENT.md`](../documents/FIPS_DEPLOYMENT.md) deep-dive describing identity mapping, npub-as-caller, and operator setup. Cross-link from [`README.md`](../README.md) section 7 (Transport).
+
+Execution tasks for initial FIPS trial:
+
+- [x] Deliver T2 TCP listener as FIPS substrate prerequisite.
+- [x] Document signer/caller qube deployment flow in [`documents/FIPS_DEPLOYMENT.md`](../documents/FIPS_DEPLOYMENT.md).
+- [ ] Add two-node operator validation script (manual) using `fipsctl` + framed JSON-RPC client.
+- [ ] Evaluate optional caller identity enrichment from FIPS session metadata.
+
+### 7.5 Phase T5 — USB / serial transport
+
+Two distinct sub-tracks; do not conflate.
+
+- T5a (firmware-side, MCU): ESP32/USB-CDC. Already in the [`firmware/`](../firmware/) track. Same dispatcher; transport adapter is UART read/write loop. `caller_identity_t.kind=usb_serial` with `asserted_caller` because the host claims the identity.
+- T5b (host-side optional): `nsigner --listen serial:/dev/ttyACM0,baud=115200`. Useful for desktop signer reachable by a USB-tethered client. Same frame protocol over the serial line. Marks identity as asserted (low trust) and forces approval prompt.
+- USB-as-Ethernet (gadget mode, RNDIS/ECM) is **not** a separate transport — it reduces to T2/T3.
+- Tests: loopback pty pair (`openpty`) for T5b unit/integration coverage; firmware-side covered in firmware track.
+
+### 7.6 Cross-cutting concerns
+
+Apply once per phase as needed:
+
+- Transport-aware approval prompt: clear visual indication of transport kind and identity (uid vs qube vs npub vs serial-asserted). No silent identity-source confusion.
+- Per-transport policy gates: deny-by-default for new identity kinds until operator explicitly enables them in policy.
+- Discovery (`nsigner list`) becomes per-transport pluggable (proc/net/unix today, internal registry for tcp, qrexec service announce for qubes, fips peer table for fips).
+- Audit logging: include transport kind and identity descriptor in every approval/decision record.
+- Error name parity: every new transport introduces only well-named errors (extend the table in [`CLIENT_IMPLEMENTATION.md`](../CLIENT_IMPLEMENTATION.md) section 5).
+
+### 7.7 Decision points (open)
+
+- D1: Land T0 (refactor) before any transport, or in parallel with T1?
+- D2: Bundle T2 and T3 as one phase, or hard split (loopback-only first, then remote-with-TLS later)?
+- D3: T4 FIPS — embed an explicit `caller_kind=fips` path in nsigner now, or treat FIPS as plain TCP and revisit identity enrichment after a working deployment?
+- D4: T5b host-side serial — in scope for desktop nsigner, or strictly firmware track?
+- D5: Qubes packaging — ship `packaging/qubes/` artifacts in this repo, or document only and let operators wire it up?

src/cjson/cJSON.h

@@ -1,306 +0,0 @@
-/*
-  Copyright (c) 2009-2017 Dave Gamble and cJSON contributors
-
-  Permission is hereby granted, free of charge, to any person obtaining a copy
-  of this software and associated documentation files (the "Software"), to deal
-  in the Software without restriction, including without limitation the rights
-  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-  copies of the Software, and to permit persons to whom the Software is
-  furnished to do so, subject to the following conditions:
-
-  The above copyright notice and this permission notice shall be included in
-  all copies or substantial portions of the Software.
-
-  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-  THE SOFTWARE.
-*/
-
-#ifndef cJSON__h
-#define cJSON__h
-
-#ifdef __cplusplus
-extern "C"
-{
-#endif
-
-#if !defined(__WINDOWS__) && (defined(WIN32) || defined(WIN64) || defined(_MSC_VER) || defined(_WIN32))
-#define __WINDOWS__
-#endif
-
-#ifdef __WINDOWS__
-
-/* When compiling for windows, we specify a specific calling convention to avoid issues where we are being called from a project with a different default calling convention.  For windows you have 3 define options:
-
-CJSON_HIDE_SYMBOLS - Define this in the case where you don't want to ever dllexport symbols
-CJSON_EXPORT_SYMBOLS - Define this on library build when you want to dllexport symbols (default)
-CJSON_IMPORT_SYMBOLS - Define this if you want to dllimport symbol
-
-For *nix builds that support visibility attribute, you can define similar behavior by
-
-setting default visibility to hidden by adding
--fvisibility=hidden (for gcc)
-or
--xldscope=hidden (for sun cc)
-to CFLAGS
-
-then using the CJSON_API_VISIBILITY flag to "export" the same symbols the way CJSON_EXPORT_SYMBOLS does
-
-*/
-
-#define CJSON_CDECL __cdecl
-#define CJSON_STDCALL __stdcall
-
-/* export symbols by default, this is necessary for copy pasting the C and header file */
-#if !defined(CJSON_HIDE_SYMBOLS) && !defined(CJSON_IMPORT_SYMBOLS) && !defined(CJSON_EXPORT_SYMBOLS)
-#define CJSON_EXPORT_SYMBOLS
-#endif
-
-#if defined(CJSON_HIDE_SYMBOLS)
-#define CJSON_PUBLIC(type)   type CJSON_STDCALL
-#elif defined(CJSON_EXPORT_SYMBOLS)
-#define CJSON_PUBLIC(type)   __declspec(dllexport) type CJSON_STDCALL
-#elif defined(CJSON_IMPORT_SYMBOLS)
-#define CJSON_PUBLIC(type)   __declspec(dllimport) type CJSON_STDCALL
-#endif
-#else /* !__WINDOWS__ */
-#define CJSON_CDECL
-#define CJSON_STDCALL
-
-#if (defined(__GNUC__) || defined(__SUNPRO_CC) || defined (__SUNPRO_C)) && defined(CJSON_API_VISIBILITY)
-#define CJSON_PUBLIC(type)   __attribute__((visibility("default"))) type
-#else
-#define CJSON_PUBLIC(type) type
-#endif
-#endif
-
-/* project version */
-#define CJSON_VERSION_MAJOR 1
-#define CJSON_VERSION_MINOR 7
-#define CJSON_VERSION_PATCH 18
-
-#include <stddef.h>
-
-/* cJSON Types: */
-#define cJSON_Invalid (0)
-#define cJSON_False  (1 << 0)
-#define cJSON_True   (1 << 1)
-#define cJSON_NULL   (1 << 2)
-#define cJSON_Number (1 << 3)
-#define cJSON_String (1 << 4)
-#define cJSON_Array  (1 << 5)
-#define cJSON_Object (1 << 6)
-#define cJSON_Raw    (1 << 7) /* raw json */
-
-#define cJSON_IsReference 256
-#define cJSON_StringIsConst 512
-
-/* The cJSON structure: */
-typedef struct cJSON
-{
-    /* next/prev allow you to walk array/object chains. Alternatively, use GetArraySize/GetArrayItem/GetObjectItem */
-    struct cJSON *next;
-    struct cJSON *prev;
-    /* An array or object item will have a child pointer pointing to a chain of the items in the array/object. */
-    struct cJSON *child;
-
-    /* The type of the item, as above. */
-    int type;
-
-    /* The item's string, if type==cJSON_String  and type == cJSON_Raw */
-    char *valuestring;
-    /* writing to valueint is DEPRECATED, use cJSON_SetNumberValue instead */
-    int valueint;
-    /* The item's number, if type==cJSON_Number */
-    double valuedouble;
-
-    /* The item's name string, if this item is the child of, or is in the list of subitems of an object. */
-    char *string;
-} cJSON;
-
-typedef struct cJSON_Hooks
-{
-      /* malloc/free are CDECL on Windows regardless of the default calling convention of the compiler, so ensure the hooks allow passing those functions directly. */
-      void *(CJSON_CDECL *malloc_fn)(size_t sz);
-      void (CJSON_CDECL *free_fn)(void *ptr);
-} cJSON_Hooks;
-
-typedef int cJSON_bool;
-
-/* Limits how deeply nested arrays/objects can be before cJSON rejects to parse them.
- * This is to prevent stack overflows. */
-#ifndef CJSON_NESTING_LIMIT
-#define CJSON_NESTING_LIMIT 1000
-#endif
-
-/* Limits the length of circular references can be before cJSON rejects to parse them.
- * This is to prevent stack overflows. */
-#ifndef CJSON_CIRCULAR_LIMIT
-#define CJSON_CIRCULAR_LIMIT 10000
-#endif
-
-/* returns the version of cJSON as a string */
-CJSON_PUBLIC(const char*) cJSON_Version(void);
-
-/* Supply malloc, realloc and free functions to cJSON */
-CJSON_PUBLIC(void) cJSON_InitHooks(cJSON_Hooks* hooks);
-
-/* Memory Management: the caller is always responsible to free the results from all variants of cJSON_Parse (with cJSON_Delete) and cJSON_Print (with stdlib free, cJSON_Hooks.free_fn, or cJSON_free as appropriate). The exception is cJSON_PrintPreallocated, where the caller has full responsibility of the buffer. */
-/* Supply a block of JSON, and this returns a cJSON object you can interrogate. */
-CJSON_PUBLIC(cJSON *) cJSON_Parse(const char *value);
-CJSON_PUBLIC(cJSON *) cJSON_ParseWithLength(const char *value, size_t buffer_length);
-/* ParseWithOpts allows you to require (and check) that the JSON is null terminated, and to retrieve the pointer to the final byte parsed. */
-/* If you supply a ptr in return_parse_end and parsing fails, then return_parse_end will contain a pointer to the error so will match cJSON_GetErrorPtr(). */
-CJSON_PUBLIC(cJSON *) cJSON_ParseWithOpts(const char *value, const char **return_parse_end, cJSON_bool require_null_terminated);
-CJSON_PUBLIC(cJSON *) cJSON_ParseWithLengthOpts(const char *value, size_t buffer_length, const char **return_parse_end, cJSON_bool require_null_terminated);
-
-/* Render a cJSON entity to text for transfer/storage. */
-CJSON_PUBLIC(char *) cJSON_Print(const cJSON *item);
-/* Render a cJSON entity to text for transfer/storage without any formatting. */
-CJSON_PUBLIC(char *) cJSON_PrintUnformatted(const cJSON *item);
-/* Render a cJSON entity to text using a buffered strategy. prebuffer is a guess at the final size. guessing well reduces reallocation. fmt=0 gives unformatted, =1 gives formatted */
-CJSON_PUBLIC(char *) cJSON_PrintBuffered(const cJSON *item, int prebuffer, cJSON_bool fmt);
-/* Render a cJSON entity to text using a buffer already allocated in memory with given length. Returns 1 on success and 0 on failure. */
-/* NOTE: cJSON is not always 100% accurate in estimating how much memory it will use, so to be safe allocate 5 bytes more than you actually need */
-CJSON_PUBLIC(cJSON_bool) cJSON_PrintPreallocated(cJSON *item, char *buffer, const int length, const cJSON_bool format);
-/* Delete a cJSON entity and all subentities. */
-CJSON_PUBLIC(void) cJSON_Delete(cJSON *item);
-
-/* Returns the number of items in an array (or object). */
-CJSON_PUBLIC(int) cJSON_GetArraySize(const cJSON *array);
-/* Retrieve item number "index" from array "array". Returns NULL if unsuccessful. */
-CJSON_PUBLIC(cJSON *) cJSON_GetArrayItem(const cJSON *array, int index);
-/* Get item "string" from object. Case insensitive. */
-CJSON_PUBLIC(cJSON *) cJSON_GetObjectItem(const cJSON * const object, const char * const string);
-CJSON_PUBLIC(cJSON *) cJSON_GetObjectItemCaseSensitive(const cJSON * const object, const char * const string);
-CJSON_PUBLIC(cJSON_bool) cJSON_HasObjectItem(const cJSON *object, const char *string);
-/* For analysing failed parses. This returns a pointer to the parse error. You'll probably need to look a few chars back to make sense of it. Defined when cJSON_Parse() returns 0. 0 when cJSON_Parse() succeeds. */
-CJSON_PUBLIC(const char *) cJSON_GetErrorPtr(void);
-
-/* Check item type and return its value */
-CJSON_PUBLIC(char *) cJSON_GetStringValue(const cJSON * const item);
-CJSON_PUBLIC(double) cJSON_GetNumberValue(const cJSON * const item);
-
-/* These functions check the type of an item */
-CJSON_PUBLIC(cJSON_bool) cJSON_IsInvalid(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsFalse(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsTrue(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsBool(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsNull(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsNumber(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsString(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsArray(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsObject(const cJSON * const item);
-CJSON_PUBLIC(cJSON_bool) cJSON_IsRaw(const cJSON * const item);
-
-/* These calls create a cJSON item of the appropriate type. */
-CJSON_PUBLIC(cJSON *) cJSON_CreateNull(void);
-CJSON_PUBLIC(cJSON *) cJSON_CreateTrue(void);
-CJSON_PUBLIC(cJSON *) cJSON_CreateFalse(void);
-CJSON_PUBLIC(cJSON *) cJSON_CreateBool(cJSON_bool boolean);
-CJSON_PUBLIC(cJSON *) cJSON_CreateNumber(double num);
-CJSON_PUBLIC(cJSON *) cJSON_CreateString(const char *string);
-/* raw json */
-CJSON_PUBLIC(cJSON *) cJSON_CreateRaw(const char *raw);
-CJSON_PUBLIC(cJSON *) cJSON_CreateArray(void);
-CJSON_PUBLIC(cJSON *) cJSON_CreateObject(void);
-
-/* Create a string where valuestring references a string so
- * it will not be freed by cJSON_Delete */
-CJSON_PUBLIC(cJSON *) cJSON_CreateStringReference(const char *string);
-/* Create an object/array that only references it's elements so
- * they will not be freed by cJSON_Delete */
-CJSON_PUBLIC(cJSON *) cJSON_CreateObjectReference(const cJSON *child);
-CJSON_PUBLIC(cJSON *) cJSON_CreateArrayReference(const cJSON *child);
-
-/* These utilities create an Array of count items.
- * The parameter count cannot be greater than the number of elements in the number array, otherwise array access will be out of bounds.*/
-CJSON_PUBLIC(cJSON *) cJSON_CreateIntArray(const int *numbers, int count);
-CJSON_PUBLIC(cJSON *) cJSON_CreateFloatArray(const float *numbers, int count);
-CJSON_PUBLIC(cJSON *) cJSON_CreateDoubleArray(const double *numbers, int count);
-CJSON_PUBLIC(cJSON *) cJSON_CreateStringArray(const char *const *strings, int count);
-
-/* Append item to the specified array/object. */
-CJSON_PUBLIC(cJSON_bool) cJSON_AddItemToArray(cJSON *array, cJSON *item);
-CJSON_PUBLIC(cJSON_bool) cJSON_AddItemToObject(cJSON *object, const char *string, cJSON *item);
-/* Use this when string is definitely const (i.e. a literal, or as good as), and will definitely survive the cJSON object.
- * WARNING: When this function was used, make sure to always check that (item->type & cJSON_StringIsConst) is zero before
- * writing to `item->string` */
-CJSON_PUBLIC(cJSON_bool) cJSON_AddItemToObjectCS(cJSON *object, const char *string, cJSON *item);
-/* Append reference to item to the specified array/object. Use this when you want to add an existing cJSON to a new cJSON, but don't want to corrupt your existing cJSON. */
-CJSON_PUBLIC(cJSON_bool) cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item);
-CJSON_PUBLIC(cJSON_bool) cJSON_AddItemReferenceToObject(cJSON *object, const char *string, cJSON *item);
-
-/* Remove/Detach items from Arrays/Objects. */
-CJSON_PUBLIC(cJSON *) cJSON_DetachItemViaPointer(cJSON *parent, cJSON * const item);
-CJSON_PUBLIC(cJSON *) cJSON_DetachItemFromArray(cJSON *array, int which);
-CJSON_PUBLIC(void) cJSON_DeleteItemFromArray(cJSON *array, int which);
-CJSON_PUBLIC(cJSON *) cJSON_DetachItemFromObject(cJSON *object, const char *string);
-CJSON_PUBLIC(cJSON *) cJSON_DetachItemFromObjectCaseSensitive(cJSON *object, const char *string);
-CJSON_PUBLIC(void) cJSON_DeleteItemFromObject(cJSON *object, const char *string);
-CJSON_PUBLIC(void) cJSON_DeleteItemFromObjectCaseSensitive(cJSON *object, const char *string);
-
-/* Update array items. */
-CJSON_PUBLIC(cJSON_bool) cJSON_InsertItemInArray(cJSON *array, int which, cJSON *newitem); /* Shifts pre-existing items to the right. */
-CJSON_PUBLIC(cJSON_bool) cJSON_ReplaceItemViaPointer(cJSON * const parent, cJSON * const item, cJSON * replacement);
-CJSON_PUBLIC(cJSON_bool) cJSON_ReplaceItemInArray(cJSON *array, int which, cJSON *newitem);
-CJSON_PUBLIC(cJSON_bool) cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem);
-CJSON_PUBLIC(cJSON_bool) cJSON_ReplaceItemInObjectCaseSensitive(cJSON *object,const char *string,cJSON *newitem);
-
-/* Duplicate a cJSON item */
-CJSON_PUBLIC(cJSON *) cJSON_Duplicate(const cJSON *item, cJSON_bool recurse);
-/* Duplicate will create a new, identical cJSON item to the one you pass, in new memory that will
- * need to be released. With recurse!=0, it will duplicate any children connected to the item.
- * The item->next and ->prev pointers are always zero on return from Duplicate. */
-/* Recursively compare two cJSON items for equality. If either a or b is NULL or invalid, they will be considered unequal.
- * case_sensitive determines if object keys are treated case sensitive (1) or case insensitive (0) */
-CJSON_PUBLIC(cJSON_bool) cJSON_Compare(const cJSON * const a, const cJSON * const b, const cJSON_bool case_sensitive);
-
-/* Minify a strings, remove blank characters(such as ' ', '\t', '\r', '\n') from strings.
- * The input pointer json cannot point to a read-only address area, such as a string constant, 
- * but should point to a readable and writable address area. */
-CJSON_PUBLIC(void) cJSON_Minify(char *json);
-
-/* Helper functions for creating and adding items to an object at the same time.
- * They return the added item or NULL on failure. */
-CJSON_PUBLIC(cJSON*) cJSON_AddNullToObject(cJSON * const object, const char * const name);
-CJSON_PUBLIC(cJSON*) cJSON_AddTrueToObject(cJSON * const object, const char * const name);
-CJSON_PUBLIC(cJSON*) cJSON_AddFalseToObject(cJSON * const object, const char * const name);
-CJSON_PUBLIC(cJSON*) cJSON_AddBoolToObject(cJSON * const object, const char * const name, const cJSON_bool boolean);
-CJSON_PUBLIC(cJSON*) cJSON_AddNumberToObject(cJSON * const object, const char * const name, const double number);
-CJSON_PUBLIC(cJSON*) cJSON_AddStringToObject(cJSON * const object, const char * const name, const char * const string);
-CJSON_PUBLIC(cJSON*) cJSON_AddRawToObject(cJSON * const object, const char * const name, const char * const raw);
-CJSON_PUBLIC(cJSON*) cJSON_AddObjectToObject(cJSON * const object, const char * const name);
-CJSON_PUBLIC(cJSON*) cJSON_AddArrayToObject(cJSON * const object, const char * const name);
-
-/* When assigning an integer value, it needs to be propagated to valuedouble too. */
-#define cJSON_SetIntValue(object, number) ((object) ? (object)->valueint = (object)->valuedouble = (number) : (number))
-/* helper for the cJSON_SetNumberValue macro */
-CJSON_PUBLIC(double) cJSON_SetNumberHelper(cJSON *object, double number);
-#define cJSON_SetNumberValue(object, number) ((object != NULL) ? cJSON_SetNumberHelper(object, (double)number) : (number))
-/* Change the valuestring of a cJSON_String object, only takes effect when type of object is cJSON_String */
-CJSON_PUBLIC(char*) cJSON_SetValuestring(cJSON *object, const char *valuestring);
-
-/* If the object is not a boolean type this does nothing and returns cJSON_Invalid else it returns the new type*/
-#define cJSON_SetBoolValue(object, boolValue) ( \
-    (object != NULL && ((object)->type & (cJSON_False|cJSON_True))) ? \
-    (object)->type=((object)->type &(~(cJSON_False|cJSON_True)))|((boolValue)?cJSON_True:cJSON_False) : \
-    cJSON_Invalid\
-)
-
-/* Macro for iterating over an array or object */
-#define cJSON_ArrayForEach(element, array) for(element = (array != NULL) ? (array)->child : NULL; element != NULL; element = element->next)
-
-/* malloc/free objects using the malloc/free functions that have been set with cJSON_InitHooks */
-CJSON_PUBLIC(void *) cJSON_malloc(size_t size);
-CJSON_PUBLIC(void) cJSON_free(void *object);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif

src/dispatcher.c

@@ -1,9 +1,466 @@
-#include "dispatcher.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
 
-#include "enforcement.h"
-#include "selector.h"
-#include "cjson/cJSON.h"
+/* from secure_mem.h */
 
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* NIP-44 encrypt/decrypt */
+char *crypto_nip44_encrypt(const key_store_t *store, int role_index,
+                           const char *recipient_pubkey_hex, const char *plaintext);
+char *crypto_nip44_decrypt(const key_store_t *store, int role_index,
+                           const char *sender_pubkey_hex, const char *ciphertext);
+
+/* NIP-04 encrypt/decrypt */
+char *crypto_nip04_encrypt(const key_store_t *store, int role_index,
+                           const char *recipient_pubkey_hex, const char *plaintext);
+char *crypto_nip04_decrypt(const key_store_t *store, int role_index,
+                           const char *sender_pubkey_hex, const char *ciphertext);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    unknown_role
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -75,13 +532,14 @@ static char *make_success_response(const char *id, const char *result) {
     return out;
 }
 
-void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic) {
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store) {
     if (ctx == NULL) {
         return;
     }
 
     ctx->role_table = table;
     ctx->mnemonic = mnemonic;
+    ctx->key_store = key_store;
 }
 
 char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request) {
@@ -98,8 +556,11 @@ char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request)
     role_entry_t *role = NULL;
     int rc;
     const char *result = NULL;
+    char *owned_result = NULL;
+    ptrdiff_t role_index_diff;
+    int role_index;
 
-    if (ctx == NULL || ctx->role_table == NULL || ctx->mnemonic == NULL || json_request == NULL) {
+    if (ctx == NULL || ctx->role_table == NULL || ctx->mnemonic == NULL || ctx->key_store == NULL || json_request == NULL) {
         return make_error_response("null", -32600, "invalid_request");
     }
 
@@ -131,7 +592,10 @@ char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request)
 
     selector_request_init(&selector_req);
 
-    options_item = cJSON_GetArrayItem(params_item, 1);
+    {
+        int params_count = cJSON_GetArraySize(params_item);
+        options_item = (params_count > 0) ? cJSON_GetArrayItem(params_item, params_count - 1) : NULL;
+    }
     if (cJSON_IsObject(options_item)) {
         tmp = cJSON_GetObjectItemCaseSensitive(options_item, "role");
         if (tmp != NULL) {
@@ -173,7 +637,7 @@ char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request)
             return make_error_response(id_str, 1001, "ambiguous_role_selector");
         }
         if (rc == SELECTOR_ERR_NOT_FOUND) {
-            return make_error_response(id_str, 1002, "role_not_found");
+            return make_error_response(id_str, 1002, "unknown_role");
         }
         if (rc == SELECTOR_ERR_NO_DEFAULT) {
             return make_error_response(id_str, 1003, "no_default_role");
@@ -201,23 +665,93 @@ char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request)
         return make_error_response(id_str, 1006, "mnemonic_not_loaded");
     }
 
+    role_index_diff = role - &ctx->role_table->entries[0];
+    if (role_index_diff < 0 || role_index_diff >= ROLE_TABLE_MAX_ENTRIES) {
+        cJSON_Delete(root);
+        return make_error_response(id_str, -32600, "invalid_request");
+    }
+    role_index = (int)role_index_diff;
+
     if (strcmp(method, VERB_GET_PUBLIC_KEY) == 0) {
         result = role->derived ? role->pubkey_hex : "not_yet_derived";
     } else if (strcmp(method, VERB_SIGN_EVENT) == 0) {
-        result = "stub:sign_event_ok";
+        cJSON *event_item = cJSON_GetArrayItem(params_item, 0);
+        if (!cJSON_IsString(event_item) || event_item->valuestring == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+
+        owned_result = crypto_sign_event(ctx->key_store, role_index, event_item->valuestring);
+        if (owned_result == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        result = owned_result;
     } else if (strcmp(method, VERB_NIP44_ENCRYPT) == 0) {
-        result = "stub:nip44_encrypt_ok";
+        cJSON *peer_item = cJSON_GetArrayItem(params_item, 0);
+        cJSON *msg_item = cJSON_GetArrayItem(params_item, 1);
+        if (!cJSON_IsString(peer_item) || peer_item->valuestring == NULL ||
+            !cJSON_IsString(msg_item) || msg_item->valuestring == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        owned_result = crypto_nip44_encrypt(ctx->key_store, role_index, peer_item->valuestring, msg_item->valuestring);
+        if (owned_result == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        result = owned_result;
     } else if (strcmp(method, VERB_NIP44_DECRYPT) == 0) {
-        result = "stub:nip44_decrypt_ok";
+        cJSON *peer_item = cJSON_GetArrayItem(params_item, 0);
+        cJSON *msg_item = cJSON_GetArrayItem(params_item, 1);
+        if (!cJSON_IsString(peer_item) || peer_item->valuestring == NULL ||
+            !cJSON_IsString(msg_item) || msg_item->valuestring == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        owned_result = crypto_nip44_decrypt(ctx->key_store, role_index, peer_item->valuestring, msg_item->valuestring);
+        if (owned_result == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        result = owned_result;
     } else if (strcmp(method, VERB_NIP04_ENCRYPT) == 0) {
-        result = "stub:nip04_encrypt_ok";
+        cJSON *peer_item = cJSON_GetArrayItem(params_item, 0);
+        cJSON *msg_item = cJSON_GetArrayItem(params_item, 1);
+        if (!cJSON_IsString(peer_item) || peer_item->valuestring == NULL ||
+            !cJSON_IsString(msg_item) || msg_item->valuestring == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        owned_result = crypto_nip04_encrypt(ctx->key_store, role_index, peer_item->valuestring, msg_item->valuestring);
+        if (owned_result == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        result = owned_result;
     } else if (strcmp(method, VERB_NIP04_DECRYPT) == 0) {
-        result = "stub:nip04_decrypt_ok";
+        cJSON *peer_item = cJSON_GetArrayItem(params_item, 0);
+        cJSON *msg_item = cJSON_GetArrayItem(params_item, 1);
+        if (!cJSON_IsString(peer_item) || peer_item->valuestring == NULL ||
+            !cJSON_IsString(msg_item) || msg_item->valuestring == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        owned_result = crypto_nip04_decrypt(ctx->key_store, role_index, peer_item->valuestring, msg_item->valuestring);
+        if (owned_result == NULL) {
+            cJSON_Delete(root);
+            return make_error_response(id_str, -32602, "invalid_params");
+        }
+        result = owned_result;
     } else {
         cJSON_Delete(root);
         return make_error_response(id_str, -32601, "method_not_found");
     }
 
     cJSON_Delete(root);
-    return make_success_response(id_str, result);
+    {
+        char *response = make_success_response(id_str, result);
+        free(owned_result);
+        return response;
+    }
 }

src/dispatcher.h

@@ -1,42 +0,0 @@
-#ifndef NSIGNER_DISPATCHER_H
-#define NSIGNER_DISPATCHER_H
-
-#include "role_table.h"
-#include "mnemonic.h"
-
-/* Dispatcher context — holds references to shared state */
-typedef struct {
-    role_table_t *role_table;
-    mnemonic_state_t *mnemonic;
-} dispatcher_ctx_t;
-
-/* Initialize dispatcher context */
-void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic);
-
-/*
- * Process a JSON-RPC request string and produce a JSON-RPC response string.
- *
- * The caller owns the returned string and must free() it.
- * Returns NULL only on catastrophic allocation failure.
- *
- * Response format on success:
- *   { "id": "...", "result": "..." }
- *
- * Response format on error:
- *   { "id": "...", "error": { "code": <int>, "message": "..." } }
- *
- * Error codes:
- *   -32700  Parse error (invalid JSON)
- *   -32600  Invalid request (missing id/method/params)
- *   -32601  Method not found (unknown verb after enforcement)
- *   -32602  Invalid params
- *   1001    ambiguous_role_selector
- *   1002    role_not_found
- *   1003    no_default_role
- *   1004    purpose_mismatch
- *   1005    curve_mismatch
- *   1006    mnemonic_not_loaded
- */
-char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
-
-#endif /* NSIGNER_DISPATCHER_H */

src/enforcement.c

@@ -1,4 +1,452 @@
-#include "enforcement.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <string.h>
 

src/enforcement.h

@@ -1,36 +0,0 @@
-#ifndef NSIGNER_ENFORCEMENT_H
-#define NSIGNER_ENFORCEMENT_H
-
-#include "role_table.h"
-
-/* Error codes */
-#define ENFORCE_OK                0
-#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
-#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
-#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
-
-/* Known verbs */
-#define VERB_SIGN_EVENT     "sign_event"
-#define VERB_GET_PUBLIC_KEY "get_public_key"
-#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
-#define VERB_NIP44_DECRYPT  "nip44_decrypt"
-#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
-#define VERB_NIP04_DECRYPT  "nip04_decrypt"
-
-/*
- * Check whether `verb` is allowed to execute against `role`.
- * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
- *
- * The enforcement rules are:
- *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
- *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
- *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
- */
-int enforce_verb_role(const char *verb, const role_entry_t *role);
-
-/*
- * Return a human-readable error string for an enforcement error code.
- */
-const char *enforce_strerror(int err);
-
-#endif /* NSIGNER_ENFORCEMENT_H */

src/key_store.c

@@ -0,0 +1,835 @@
+#define _GNU_SOURCE
+
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Derive key for exactly one role index. Returns 0 on success, -1 on error. */
+int crypto_derive_one(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic, int role_index);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <nostr_core/nostr_common.h>
+#include <nostr_core/nip001.h>
+#include <nostr_core/nip004.h>
+#include <nostr_core/nip006.h>
+#include <nostr_core/nip019.h>
+#include <nostr_core/nip044.h>
+#include <nostr_core/utils.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#define NSIGNER_ENCRYPT_OUTPUT_MAX 65536
+
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic) {
+    int i;
+    int derived_count;
+
+    if (store == NULL || table == NULL || mnemonic == NULL) {
+        return -1;
+    }
+
+    if (!mnemonic_is_loaded(mnemonic)) {
+        return -1;
+    }
+
+    crypto_wipe(store);
+    derived_count = 0;
+
+    for (i = 0; i < table->count; ++i) {
+        role_entry_t *role = &table->entries[i];
+        unsigned char priv[32];
+        unsigned char pub[32];
+        derived_key_t *dst = &store->keys[i];
+
+        role->derived = 0;
+        role->pubkey_hex[0] = '\0';
+
+        if (role->purpose != PURPOSE_NOSTR ||
+            role->curve != CURVE_SECP256K1 ||
+            role->selector_type != SELECTOR_NOSTR_INDEX) {
+            continue;
+        }
+
+        if (secure_buf_alloc(&dst->private_key, 32) != 0) {
+            crypto_wipe(store);
+            return -1;
+        }
+
+        if (nostr_derive_keys_from_mnemonic(mnemonic_get_phrase(mnemonic), role->nostr_index, priv, pub) != 0) {
+            secure_memzero(priv, sizeof(priv));
+            secure_memzero(pub, sizeof(pub));
+            crypto_wipe(store);
+            return -1;
+        }
+
+        memcpy(dst->private_key.data, priv, 32);
+        memcpy(dst->public_key, pub, 32);
+
+        nostr_bytes_to_hex(pub, 32, dst->pubkey_hex);
+        dst->npub[0] = '\0';
+        (void)nostr_key_to_bech32(pub, "npub", dst->npub);
+
+        strncpy(role->pubkey_hex, dst->pubkey_hex, sizeof(role->pubkey_hex) - 1);
+        role->pubkey_hex[sizeof(role->pubkey_hex) - 1] = '\0';
+        role->derived = 1;
+
+        dst->valid = 1;
+        derived_count++;
+
+        secure_memzero(priv, sizeof(priv));
+        secure_memzero(pub, sizeof(pub));
+    }
+
+    store->count = table->count;
+    return derived_count;
+}
+
+int crypto_derive_one(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic, int role_index) {
+    role_entry_t *role;
+    derived_key_t *dst;
+    unsigned char priv[32];
+    unsigned char pub[32];
+
+    if (store == NULL || table == NULL || mnemonic == NULL) {
+        return -1;
+    }
+
+    if (!mnemonic_is_loaded(mnemonic)) {
+        return -1;
+    }
+
+    if (role_index < 0 || role_index >= table->count || role_index >= ROLE_TABLE_MAX_ENTRIES) {
+        return -1;
+    }
+
+    role = &table->entries[role_index];
+    dst = &store->keys[role_index];
+
+    role->derived = 0;
+    role->pubkey_hex[0] = '\0';
+
+    secure_buf_free(&dst->private_key);
+    secure_memzero(dst->public_key, sizeof(dst->public_key));
+    secure_memzero(dst->pubkey_hex, sizeof(dst->pubkey_hex));
+    secure_memzero(dst->npub, sizeof(dst->npub));
+    dst->valid = 0;
+
+    if (role->purpose != PURPOSE_NOSTR ||
+        role->curve != CURVE_SECP256K1 ||
+        role->selector_type != SELECTOR_NOSTR_INDEX) {
+        return -1;
+    }
+
+    if (secure_buf_alloc(&dst->private_key, 32) != 0) {
+        return -1;
+    }
+
+    if (nostr_derive_keys_from_mnemonic(mnemonic_get_phrase(mnemonic), role->nostr_index, priv, pub) != 0) {
+        secure_memzero(priv, sizeof(priv));
+        secure_memzero(pub, sizeof(pub));
+        secure_buf_free(&dst->private_key);
+        return -1;
+    }
+
+    memcpy(dst->private_key.data, priv, 32);
+    memcpy(dst->public_key, pub, 32);
+
+    nostr_bytes_to_hex(pub, 32, dst->pubkey_hex);
+    dst->npub[0] = '\0';
+    (void)nostr_key_to_bech32(pub, "npub", dst->npub);
+
+    strncpy(role->pubkey_hex, dst->pubkey_hex, sizeof(role->pubkey_hex) - 1);
+    role->pubkey_hex[sizeof(role->pubkey_hex) - 1] = '\0';
+    role->derived = 1;
+
+    dst->valid = 1;
+    if (store->count < table->count) {
+        store->count = table->count;
+    }
+
+    secure_memzero(priv, sizeof(priv));
+    secure_memzero(pub, sizeof(pub));
+    return 0;
+}
+
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index) {
+    if (store == NULL || role_index < 0 || role_index >= ROLE_TABLE_MAX_ENTRIES) {
+        return NULL;
+    }
+
+    if (!store->keys[role_index].valid || store->keys[role_index].private_key.data == NULL) {
+        return NULL;
+    }
+
+    return (const unsigned char *)store->keys[role_index].private_key.data;
+}
+
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index) {
+    if (store == NULL || role_index < 0 || role_index >= ROLE_TABLE_MAX_ENTRIES) {
+        return NULL;
+    }
+
+    if (!store->keys[role_index].valid) {
+        return NULL;
+    }
+
+    return store->keys[role_index].pubkey_hex;
+}
+
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json) {
+    const unsigned char *private_key;
+    cJSON *parsed = NULL;
+    cJSON *kind_item;
+    cJSON *content_item;
+    cJSON *tags_item;
+    cJSON *created_at_item;
+    cJSON *tags_for_sign = NULL;
+    int kind;
+    const char *content;
+    time_t timestamp = 0;
+    cJSON *signed_event = NULL;
+    char *out = NULL;
+
+    if (event_json == NULL) {
+        return NULL;
+    }
+
+    private_key = crypto_get_private_key(store, role_index);
+    if (private_key == NULL) {
+        return NULL;
+    }
+
+    parsed = cJSON_Parse(event_json);
+    if (parsed == NULL || !cJSON_IsObject(parsed)) {
+        cJSON_Delete(parsed);
+        return NULL;
+    }
+
+    kind_item = cJSON_GetObjectItemCaseSensitive(parsed, "kind");
+    content_item = cJSON_GetObjectItemCaseSensitive(parsed, "content");
+    tags_item = cJSON_GetObjectItemCaseSensitive(parsed, "tags");
+    created_at_item = cJSON_GetObjectItemCaseSensitive(parsed, "created_at");
+
+    if (!cJSON_IsNumber(kind_item) || !cJSON_IsString(content_item) || content_item->valuestring == NULL) {
+        cJSON_Delete(parsed);
+        return NULL;
+    }
+
+    kind = kind_item->valueint;
+    content = content_item->valuestring;
+
+    if (cJSON_IsNumber(created_at_item)) {
+        timestamp = (time_t)created_at_item->valuedouble;
+    }
+
+    if (cJSON_IsArray(tags_item)) {
+        tags_for_sign = cJSON_Duplicate(tags_item, 1);
+        if (tags_for_sign == NULL) {
+            cJSON_Delete(parsed);
+            return NULL;
+        }
+    }
+
+    signed_event = nostr_create_and_sign_event(kind, content, tags_for_sign, private_key, timestamp);
+    cJSON_Delete(tags_for_sign);
+    cJSON_Delete(parsed);
+
+    if (signed_event == NULL) {
+        return NULL;
+    }
+
+    out = cJSON_PrintUnformatted(signed_event);
+    cJSON_Delete(signed_event);
+    return out;
+}
+
+static int parse_hex_pubkey32(const char *hex, unsigned char out[32]) {
+    if (hex == NULL || out == NULL || strlen(hex) != 64) {
+        return -1;
+    }
+    if (nostr_hex_to_bytes(hex, out, 32) != 0) {
+        return -1;
+    }
+    return 0;
+}
+
+char *crypto_nip44_encrypt(const key_store_t *store, int role_index,
+                           const char *recipient_pubkey_hex, const char *plaintext) {
+    const unsigned char *private_key;
+    unsigned char recipient_pub[32];
+    char *out;
+
+    if (plaintext == NULL || recipient_pubkey_hex == NULL) {
+        return NULL;
+    }
+
+    private_key = crypto_get_private_key(store, role_index);
+    if (private_key == NULL || parse_hex_pubkey32(recipient_pubkey_hex, recipient_pub) != 0) {
+        return NULL;
+    }
+
+    out = (char *)malloc(NSIGNER_ENCRYPT_OUTPUT_MAX);
+    if (out == NULL) {
+        return NULL;
+    }
+    out[0] = '\0';
+
+    if (nostr_nip44_encrypt(private_key, recipient_pub, plaintext, out, NSIGNER_ENCRYPT_OUTPUT_MAX) != 0) {
+        free(out);
+        return NULL;
+    }
+
+    return out;
+}
+
+char *crypto_nip44_decrypt(const key_store_t *store, int role_index,
+                           const char *sender_pubkey_hex, const char *ciphertext) {
+    const unsigned char *private_key;
+    unsigned char sender_pub[32];
+    char *out;
+
+    if (ciphertext == NULL || sender_pubkey_hex == NULL) {
+        return NULL;
+    }
+
+    private_key = crypto_get_private_key(store, role_index);
+    if (private_key == NULL || parse_hex_pubkey32(sender_pubkey_hex, sender_pub) != 0) {
+        return NULL;
+    }
+
+    out = (char *)malloc(NSIGNER_ENCRYPT_OUTPUT_MAX);
+    if (out == NULL) {
+        return NULL;
+    }
+    out[0] = '\0';
+
+    if (nostr_nip44_decrypt(private_key, sender_pub, ciphertext, out, NSIGNER_ENCRYPT_OUTPUT_MAX) != 0) {
+        free(out);
+        return NULL;
+    }
+
+    return out;
+}
+
+char *crypto_nip04_encrypt(const key_store_t *store, int role_index,
+                           const char *recipient_pubkey_hex, const char *plaintext) {
+    const unsigned char *private_key;
+    unsigned char recipient_pub[32];
+    char *out;
+
+    if (plaintext == NULL || recipient_pubkey_hex == NULL) {
+        return NULL;
+    }
+
+    private_key = crypto_get_private_key(store, role_index);
+    if (private_key == NULL || parse_hex_pubkey32(recipient_pubkey_hex, recipient_pub) != 0) {
+        return NULL;
+    }
+
+    out = (char *)malloc(NSIGNER_ENCRYPT_OUTPUT_MAX);
+    if (out == NULL) {
+        return NULL;
+    }
+    out[0] = '\0';
+
+    if (nostr_nip04_encrypt(private_key, recipient_pub, plaintext, out, NSIGNER_ENCRYPT_OUTPUT_MAX) != 0) {
+        free(out);
+        return NULL;
+    }
+
+    return out;
+}
+
+char *crypto_nip04_decrypt(const key_store_t *store, int role_index,
+                           const char *sender_pubkey_hex, const char *ciphertext) {
+    const unsigned char *private_key;
+    unsigned char sender_pub[32];
+    char *out;
+
+    if (ciphertext == NULL || sender_pubkey_hex == NULL) {
+        return NULL;
+    }
+
+    private_key = crypto_get_private_key(store, role_index);
+    if (private_key == NULL || parse_hex_pubkey32(sender_pubkey_hex, sender_pub) != 0) {
+        return NULL;
+    }
+
+    out = (char *)malloc(NSIGNER_ENCRYPT_OUTPUT_MAX);
+    if (out == NULL) {
+        return NULL;
+    }
+    out[0] = '\0';
+
+    if (nostr_nip04_decrypt(private_key, sender_pub, ciphertext, out, NSIGNER_ENCRYPT_OUTPUT_MAX) != 0) {
+        free(out);
+        return NULL;
+    }
+
+    return out;
+}
+
+void crypto_wipe(key_store_t *store) {
+    int i;
+
+    if (store == NULL) {
+        return;
+    }
+
+    for (i = 0; i < ROLE_TABLE_MAX_ENTRIES; ++i) {
+        secure_buf_free(&store->keys[i].private_key);
+        secure_memzero(store->keys[i].public_key, sizeof(store->keys[i].public_key));
+        secure_memzero(store->keys[i].pubkey_hex, sizeof(store->keys[i].pubkey_hex));
+        secure_memzero(store->keys[i].npub, sizeof(store->keys[i].npub));
+        store->keys[i].valid = 0;
+    }
+
+    store->count = 0;
+}

src/main.h

@@ -1,16 +0,0 @@
-/*
- * nsigner main header - version information
- *
- * Version macros are auto-updated by increment_and_push.sh.
- */
-
-#ifndef NSIGNER_MAIN_H
-#define NSIGNER_MAIN_H
-
-/* Version information (auto-updated by build/version tooling) */
-#define NSIGNER_VERSION_MAJOR 0
-#define NSIGNER_VERSION_MINOR 0
-#define NSIGNER_VERSION_PATCH 1
-#define NSIGNER_VERSION "v0.0.1"
-
-#endif /* NSIGNER_MAIN_H */

src/mnemonic.c

@@ -1,7 +1,459 @@
-#include "mnemonic.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
 
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <nostr_core/utils.h>
+
+#include <errno.h>
 #include <stddef.h>
 #include <string.h>
+#include <sys/random.h>
 
 /* Return 1 if the word count is an allowed BIP39 mnemonic length. */
 static int mnemonic_is_valid_word_count(int count) {
@@ -101,3 +553,55 @@ const char *mnemonic_get_phrase(const mnemonic_state_t *state) {
 
     return (const char *)state->buf.data;
 }
+
+int mnemonic_generate(int word_count, char *out, size_t out_len) {
+    unsigned char entropy[32];
+    size_t entropy_len = 0;
+    size_t off = 0;
+    char phrase[MNEMONIC_MAX_LEN];
+
+    if (out == NULL || out_len == 0 || !mnemonic_is_valid_word_count(word_count)) {
+        return -1;
+    }
+
+    switch (word_count) {
+        case 12: entropy_len = 16; break;
+        case 15: entropy_len = 20; break;
+        case 18: entropy_len = 24; break;
+        case 21: entropy_len = 28; break;
+        case 24: entropy_len = 32; break;
+        default:
+            return -1;
+    }
+
+    memset(entropy, 0, sizeof(entropy));
+    while (off < entropy_len) {
+        ssize_t rc = getrandom(entropy + off, entropy_len - off, 0);
+        if (rc < 0) {
+            if (errno == EINTR) {
+                continue;
+            }
+            secure_memzero(entropy, sizeof(entropy));
+            return -1;
+        }
+        off += (size_t)rc;
+    }
+
+    memset(phrase, 0, sizeof(phrase));
+    if (nostr_bip39_mnemonic_from_bytes(entropy, entropy_len, phrase) != 0) {
+        secure_memzero(entropy, sizeof(entropy));
+        secure_memzero(phrase, sizeof(phrase));
+        return -1;
+    }
+
+    secure_memzero(entropy, sizeof(entropy));
+
+    if (strlen(phrase) + 1 > out_len) {
+        secure_memzero(phrase, sizeof(phrase));
+        return -1;
+    }
+
+    strcpy(out, phrase);
+    secure_memzero(phrase, sizeof(phrase));
+    return 0;
+}

src/mnemonic.h

@@ -1,35 +0,0 @@
-#ifndef NSIGNER_MNEMONIC_H
-#define NSIGNER_MNEMONIC_H
-
-#include "secure_mem.h"
-
-/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
-#define MNEMONIC_MAX_LEN 256
-
-/*
- * Mnemonic state — holds the loaded mnemonic in secure memory.
- * Only one mnemonic is active at a time per process.
- */
-typedef struct {
-    secure_buf_t buf;       /* secure storage for the mnemonic string */
-    int loaded;             /* 1 if a mnemonic is currently loaded */
-    int word_count;         /* 12, 15, 18, 21, or 24 */
-} mnemonic_state_t;
-
-/* Initialize mnemonic state (must be called before use). */
-void mnemonic_init(mnemonic_state_t *state);
-
-/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
- * Returns 0 on success, -1 on invalid input, -2 on memory error. */
-int mnemonic_load(mnemonic_state_t *state, const char *phrase);
-
-/* Zeroize and unload the mnemonic. Idempotent. */
-void mnemonic_unload(mnemonic_state_t *state);
-
-/* Check if a mnemonic is currently loaded. */
-int mnemonic_is_loaded(const mnemonic_state_t *state);
-
-/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
-const char *mnemonic_get_phrase(const mnemonic_state_t *state);
-
-#endif /* NSIGNER_MNEMONIC_H */

src/policy.c

@@ -1,6 +1,456 @@
-#include "policy.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
 
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <errno.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 
 static void copy_str(char *dst, size_t dst_sz, const char *src) {
@@ -100,6 +550,112 @@ const char *prompt_mode_to_str(prompt_mode_t m) {
     }
 }
 
+int parse_preapprove_spec(const char *spec, policy_entry_t *out_entry, int *out_nostr_index) {
+    char *spec_copy;
+    char *token;
+    const char *caller = NULL;
+    const char *role = NULL;
+    int nostr_index = -1;
+    int has_role = 0;
+    int has_nostr_index = 0;
+
+    if (out_nostr_index != NULL) {
+        *out_nostr_index = -1;
+    }
+
+    if (spec == NULL || out_entry == NULL) {
+        fprintf(stderr, "ERROR: invalid --preapprove arguments\n");
+        return -1;
+    }
+
+    spec_copy = (char *)malloc(strlen(spec) + 1);
+    if (spec_copy == NULL) {
+        fprintf(stderr, "ERROR: out of memory parsing --preapprove spec: %s\n", spec);
+        return -1;
+    }
+    memcpy(spec_copy, spec, strlen(spec) + 1);
+
+    token = strtok(spec_copy, ",");
+    while (token != NULL) {
+        char *eq = strchr(token, '=');
+        if (eq == NULL || eq == token || eq[1] == '\0') {
+            fprintf(stderr, "ERROR: invalid --preapprove key=value field: %s\n", spec);
+            free(spec_copy);
+            return -1;
+        }
+
+        *eq = '\0';
+        if (strcmp(token, "caller") == 0) {
+            caller = eq + 1;
+        } else if (strcmp(token, "role") == 0) {
+            role = eq + 1;
+            has_role = 1;
+        } else if (strcmp(token, "nostr_index") == 0) {
+            char *endptr = NULL;
+            long val;
+
+            errno = 0;
+            val = strtol(eq + 1, &endptr, 10);
+            if (errno != 0 || endptr == (eq + 1) || *endptr != '\0' || val < 0) {
+                fprintf(stderr, "ERROR: --preapprove spec has invalid nostr_index= value: %s\n", spec);
+                free(spec_copy);
+                return -1;
+            }
+            nostr_index = (int)val;
+            has_nostr_index = 1;
+        } else {
+            fprintf(stderr, "ERROR: unknown --preapprove field '%s' in spec: %s\n", token, spec);
+            free(spec_copy);
+            return -1;
+        }
+
+        token = strtok(NULL, ",");
+    }
+
+    if (caller == NULL) {
+        fprintf(stderr, "ERROR: --preapprove spec missing 'caller=' field: %s\n", spec);
+        free(spec_copy);
+        return -1;
+    }
+
+    if (!has_role && !has_nostr_index) {
+        fprintf(stderr, "ERROR: --preapprove spec must include 'role=' or 'nostr_index=': %s\n", spec);
+        free(spec_copy);
+        return -1;
+    }
+
+    if (has_role && has_nostr_index) {
+        fprintf(stderr, "ERROR: --preapprove spec has both 'role=' and 'nostr_index=' (use one): %s\n", spec);
+        free(spec_copy);
+        return -1;
+    }
+
+    memset(out_entry, 0, sizeof(*out_entry));
+    strncpy(out_entry->caller, caller, sizeof(out_entry->caller) - 1);
+    out_entry->caller[sizeof(out_entry->caller) - 1] = '\0';
+
+    if (has_role) {
+        strncpy(out_entry->roles[0], role, sizeof(out_entry->roles[0]) - 1);
+        out_entry->roles[0][sizeof(out_entry->roles[0]) - 1] = '\0';
+    } else {
+        if (nostr_index == 0) {
+            strncpy(out_entry->roles[0], "main", sizeof(out_entry->roles[0]) - 1);
+            out_entry->roles[0][sizeof(out_entry->roles[0]) - 1] = '\0';
+        } else {
+            (void)snprintf(out_entry->roles[0], sizeof(out_entry->roles[0]), "nostr_idx_%d", nostr_index);
+        }
+        if (out_nostr_index != NULL) {
+            *out_nostr_index = nostr_index;
+        }
+    }
+
+    out_entry->role_count = 1;
+    out_entry->prompt = PROMPT_NEVER;
+
+    free(spec_copy);
+    return 0;
+}
+
 void policy_table_init(policy_table_t *table) {
     if (table == NULL) {
         return;
@@ -109,8 +665,9 @@ void policy_table_init(policy_table_t *table) {
 }
 
 void policy_init_default(policy_table_t *table, uid_t owner_uid) {
-    policy_entry_t allow_owner;
-    policy_entry_t deny_all;
+    policy_entry_t prompt_all;
+
+    (void)owner_uid;
 
     if (table == NULL) {
         return;
@@ -118,15 +675,11 @@ void policy_init_default(policy_table_t *table, uid_t owner_uid) {
 
     policy_table_init(table);
 
-    memset(&allow_owner, 0, sizeof(allow_owner));
-    (void)snprintf(allow_owner.caller, sizeof(allow_owner.caller), "uid:%u", (unsigned int)owner_uid);
-    allow_owner.prompt = PROMPT_NEVER;
-    (void)policy_table_add(table, &allow_owner);
-
-    memset(&deny_all, 0, sizeof(deny_all));
-    copy_str(deny_all.caller, sizeof(deny_all.caller), "*");
-    deny_all.prompt = PROMPT_DENY;
-    (void)policy_table_add(table, &deny_all);
+    memset(&prompt_all, 0, sizeof(prompt_all));
+    copy_str(prompt_all.caller, sizeof(prompt_all.caller), "*");
+    prompt_all.prompt = PROMPT_EVERY_REQUEST;
+    prompt_all.source = POLICY_SOURCE_DEFAULT;
+    (void)policy_table_add(table, &prompt_all);
 }
 
 int policy_table_add(policy_table_t *table, const policy_entry_t *entry) {
@@ -143,10 +696,34 @@ int policy_table_add(policy_table_t *table, const policy_entry_t *entry) {
     return 0;
 }
 
+int policy_table_insert_before_last(policy_table_t *table, const policy_entry_t *entry) {
+    if (table == NULL || entry == NULL) {
+        return -1;
+    }
+
+    if (table->count >= POLICY_MAX_ENTRIES) {
+        return -1;
+    }
+
+    if (table->count == 0) {
+        return policy_table_add(table, entry);
+    }
+
+    table->entries[table->count] = table->entries[table->count - 1];
+    table->entries[table->count - 1] = *entry;
+    table->count++;
+    return 0;
+}
+
 int policy_check(const policy_table_t *table, const char *caller_id,
-                 const char *verb, const char *role_name, const char *purpose) {
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source) {
     int i;
 
+    if (out_source != NULL) {
+        *out_source = POLICY_SOURCE_DEFAULT;
+    }
+
     if (table == NULL || caller_id == NULL || verb == NULL || role_name == NULL || purpose == NULL) {
         return POLICY_NO_MATCH;
     }
@@ -178,12 +755,20 @@ int policy_check(const policy_table_t *table, const char *caller_id,
             continue;
         }
 
+        if (out_source != NULL) {
+            *out_source = entry->source;
+        }
+
         if (entry->prompt == PROMPT_DENY) {
             return POLICY_DENY;
         }
         if (entry->prompt == PROMPT_NEVER) {
             return POLICY_ALLOW;
         }
+
+        if (out_source != NULL) {
+            *out_source = POLICY_SOURCE_DEFAULT;
+        }
         return POLICY_PROMPT;
     }
 

src/policy.h

@@ -1,68 +0,0 @@
-#ifndef NSIGNER_POLICY_H
-#define NSIGNER_POLICY_H
-
-#include "role_table.h"
-#include <sys/types.h>
-
-#define POLICY_MAX_ENTRIES    32
-#define POLICY_MAX_VERBS      16
-#define POLICY_MAX_ROLES      16
-#define POLICY_MAX_PURPOSES   8
-#define POLICY_VERB_MAX_LEN   32
-#define POLICY_CALLER_MAX_LEN 64
-
-/* Prompt behavior */
-typedef enum {
-    PROMPT_NEVER = 0,
-    PROMPT_FIRST_PER_BOOT,
-    PROMPT_EVERY_REQUEST,
-    PROMPT_DENY
-} prompt_mode_t;
-
-/* A single policy entry */
-typedef struct {
-    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
-    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
-    int verb_count;
-    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
-    int role_count;
-    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
-    int purpose_count;
-    prompt_mode_t prompt;
-} policy_entry_t;
-
-/* Policy table */
-typedef struct {
-    policy_entry_t entries[POLICY_MAX_ENTRIES];
-    int count;
-} policy_table_t;
-
-/* Policy check result */
-#define POLICY_ALLOW     0
-#define POLICY_DENY     -1
-#define POLICY_PROMPT   -2   /* would need user confirmation */
-#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
-
-/* Initialize policy table */
-void policy_table_init(policy_table_t *table);
-
-/* Initialize default policy: allow same-uid, deny others */
-void policy_init_default(policy_table_t *table, uid_t owner_uid);
-
-/* Add a policy entry. Returns 0 on success, -1 if full. */
-int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
-
-/*
- * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
- * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
- */
-int policy_check(const policy_table_t *table, const char *caller_id,
-                 const char *verb, const char *role_name, const char *purpose);
-
-/* Parse prompt mode from string */
-prompt_mode_t prompt_mode_from_str(const char *s);
-
-/* Prompt mode to string */
-const char *prompt_mode_to_str(prompt_mode_t m);
-
-#endif /* NSIGNER_POLICY_H */

src/role_table.c

@@ -1,5 +1,457 @@
-#include "role_table.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
 
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+/* Register a nostr-index role if missing. Returns 0 on success, -1 on error. */
+int role_table_register_nostr_index(role_table_t *table, int nostr_index);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <stdio.h>
 #include <string.h>
 
 static int str_eq(const char *a, const char *b) {
@@ -93,6 +545,36 @@ role_entry_t *role_table_get_default(role_table_t *table) {
     return role_table_find_by_name(table, "main");
 }
 
+int role_table_register_nostr_index(role_table_t *table, int nostr_index) {
+    role_entry_t role;
+
+    if (table == NULL || nostr_index < 0) {
+        return -1;
+    }
+
+    if (role_table_find_by_nostr_index(table, nostr_index) != NULL) {
+        return 0;
+    }
+
+    memset(&role, 0, sizeof(role));
+
+    if (nostr_index == 0) {
+        strncpy(role.name, "main", sizeof(role.name) - 1);
+    } else {
+        (void)snprintf(role.name, sizeof(role.name), "nostr_idx_%d", nostr_index);
+    }
+
+    strncpy(role.purpose_str, "nostr", sizeof(role.purpose_str) - 1);
+    strncpy(role.curve_str, "secp256k1", sizeof(role.curve_str) - 1);
+    role.purpose = role_purpose_from_str(role.purpose_str);
+    role.curve = role_curve_from_str(role.curve_str);
+    role.selector_type = SELECTOR_NOSTR_INDEX;
+    role.nostr_index = nostr_index;
+    role.derived = 0;
+
+    return role_table_add(table, &role);
+}
+
 role_purpose_t role_purpose_from_str(const char *s) {
     if (str_eq(s, "nostr")) {
         return PURPOSE_NOSTR;

src/role_table.h

@@ -1,89 +0,0 @@
-#ifndef NSIGNER_ROLE_TABLE_H
-#define NSIGNER_ROLE_TABLE_H
-
-#include <stddef.h>
-#include <stdint.h>
-
-/* Maximum limits */
-#define ROLE_NAME_MAX 64
-#define ROLE_PATH_MAX 128
-#define ROLE_PURPOSE_MAX 32
-#define ROLE_CURVE_MAX 16
-#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
-#define ROLE_TABLE_MAX_ENTRIES 64
-
-/* Purpose enum for fast comparison (string form kept for config/display) */
-typedef enum {
-    PURPOSE_NOSTR = 0,
-    PURPOSE_BITCOIN,
-    PURPOSE_SSH,
-    PURPOSE_AGE,
-    PURPOSE_FIPS,
-    PURPOSE_UNKNOWN
-} role_purpose_t;
-
-/* Curve enum */
-typedef enum {
-    CURVE_SECP256K1 = 0,
-    CURVE_ED25519,
-    CURVE_X25519,
-    CURVE_UNKNOWN
-} role_curve_t;
-
-/* Selector type — how this role's key is addressed */
-typedef enum {
-    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
-    SELECTOR_ROLE_PATH    /* uses explicit full path */
-} role_selector_type_t;
-
-/* A single role entry */
-typedef struct {
-    char name[ROLE_NAME_MAX];
-    char purpose_str[ROLE_PURPOSE_MAX];
-    char curve_str[ROLE_CURVE_MAX];
-    role_purpose_t purpose;
-    role_curve_t curve;
-    role_selector_type_t selector_type;
-    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
-    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
-    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
-    int derived;                             /* 1 if pubkey_hex has been populated */
-} role_entry_t;
-
-/* The role table */
-typedef struct {
-    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
-    int count;
-} role_table_t;
-
-/* Initialize an empty role table */
-void role_table_init(role_table_t *table);
-
-/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
-int role_table_add(role_table_t *table, const role_entry_t *entry);
-
-/* Find a role by name. Returns pointer to entry or NULL. */
-role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
-
-/* Find a role by nostr_index. Returns pointer or NULL. */
-role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
-
-/* Find a role by role_path. Returns pointer or NULL. */
-role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
-
-/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
-role_entry_t *role_table_get_default(role_table_t *table);
-
-/* Parse purpose string to enum */
-role_purpose_t role_purpose_from_str(const char *s);
-
-/* Parse curve string to enum */
-role_curve_t role_curve_from_str(const char *s);
-
-/* Purpose enum to string */
-const char *role_purpose_to_str(role_purpose_t p);
-
-/* Curve enum to string */
-const char *role_curve_to_str(role_curve_t c);
-
-#endif /* NSIGNER_ROLE_TABLE_H */

src/secure_mem.c

@@ -1,6 +1,454 @@
 #define _GNU_SOURCE
 
-#include "secure_mem.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <stdio.h>
 #include <stdlib.h>

src/secure_mem.h

@@ -1,25 +0,0 @@
-#ifndef NSIGNER_SECURE_MEM_H
-#define NSIGNER_SECURE_MEM_H
-
-#include <stddef.h>
-
-/*
- * Secure memory buffer — mlock'd, zeroized on free.
- * Used for mnemonic phrases, private keys, and any sensitive material.
- */
-typedef struct {
-    void *data;       /* pointer to locked allocation */
-    size_t size;      /* usable size in bytes */
-    int locked;       /* 1 if mlock succeeded */
-} secure_buf_t;
-
-/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
-int secure_buf_alloc(secure_buf_t *buf, size_t size);
-
-/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
-void secure_buf_free(secure_buf_t *buf);
-
-/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
-void secure_memzero(void *ptr, size_t len);
-
-#endif /* NSIGNER_SECURE_MEM_H */

src/selector.c

@@ -1,4 +1,452 @@
-#include "selector.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <string.h>
 

src/selector.h

@@ -1,39 +0,0 @@
-#ifndef NSIGNER_SELECTOR_H
-#define NSIGNER_SELECTOR_H
-
-#include "role_table.h"
-
-/* Error codes for selector resolution */
-#define SELECTOR_OK                 0
-#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
-#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
-#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
-
-/* Parsed selector from a request's options object */
-typedef struct {
-    int has_role;          /* 1 if "role" field was present */
-    char role_name[ROLE_NAME_MAX];
-
-    int has_nostr_index;   /* 1 if "nostr_index" field was present */
-    int nostr_index;
-
-    int has_role_path;     /* 1 if "role_path" field was present */
-    char role_path[ROLE_PATH_MAX];
-} selector_request_t;
-
-/* Initialize a selector request (all fields zeroed/unset) */
-void selector_request_init(selector_request_t *req);
-
-/*
- * Resolve a selector request against the role table.
- * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
- * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
- */
-int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
-
-/*
- * Return a human-readable error string for a selector error code.
- */
-const char *selector_strerror(int err);
-
-#endif /* NSIGNER_SELECTOR_H */

src/server.h

@@ -1,46 +0,0 @@
-#ifndef NSIGNER_SERVER_H
-#define NSIGNER_SERVER_H
-
-#include "dispatcher.h"
-#include "policy.h"
-#include <sys/types.h>
-
-#define SERVER_SOCKET_NAME_MAX 108
-#define SERVER_MAX_MSG_SIZE    65536
-
-/* Caller identity */
-typedef struct {
-    uid_t uid;
-    gid_t gid;
-    pid_t pid;
-    char caller_id[64];  /* "uid:<n>" */
-} caller_identity_t;
-
-/* Server context */
-typedef struct {
-    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
-    int listen_fd;
-    int running;
-    dispatcher_ctx_t *dispatcher;
-    policy_table_t *policy;
-} server_ctx_t;
-
-/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner") */
-void server_init(server_ctx_t *ctx, const char *socket_name,
-                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
-
-/* Start listening. Returns 0 on success, -1 on error. */
-int server_start(server_ctx_t *ctx);
-
-/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
- * activity_cb is called with a description string for the TUI activity log. */
-typedef void (*server_activity_cb)(const char *message, void *user_data);
-int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
-
-/* Stop server and close socket */
-void server_stop(server_ctx_t *ctx);
-
-/* Extract caller identity from connected fd */
-int server_get_caller(int fd, caller_identity_t *out);
-
-#endif /* NSIGNER_SERVER_H */

src/socket_name.c

@@ -0,0 +1,517 @@
+#define _GNU_SOURCE
+
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <nostr_core/utils.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/random.h>
+
+static int fill_random(unsigned char *buf, size_t len) {
+    size_t off = 0;
+
+    while (off < len) {
+        ssize_t rc = getrandom(buf + off, len - off, 0);
+        if (rc < 0) {
+            if (errno == EINTR) {
+                continue;
+            }
+            return -1;
+        }
+        off += (size_t)rc;
+    }
+
+    return 0;
+}
+
+int socket_name_random(char *out, size_t out_len) {
+    unsigned char entropy[16];
+    char mnemonic[256];
+    char *sp1;
+    char *sp2;
+
+    if (out == NULL || out_len == 0) {
+        return -1;
+    }
+
+    if (fill_random(entropy, sizeof(entropy)) != 0) {
+        return -1;
+    }
+
+    memset(mnemonic, 0, sizeof(mnemonic));
+    if (nostr_bip39_mnemonic_from_bytes(entropy, sizeof(entropy), mnemonic) != 0) {
+        memset(entropy, 0, sizeof(entropy));
+        return -1;
+    }
+    memset(entropy, 0, sizeof(entropy));
+
+    sp1 = strchr(mnemonic, ' ');
+    if (sp1 == NULL) {
+        memset(mnemonic, 0, sizeof(mnemonic));
+        return -1;
+    }
+    *sp1 = '\0';
+
+    sp2 = strchr(sp1 + 1, ' ');
+    if (sp2 != NULL) {
+        *sp2 = '\0';
+    }
+
+    if (snprintf(out, out_len, "nsigner_%s_%s", mnemonic, sp1 + 1) >= (int)out_len) {
+        memset(mnemonic, 0, sizeof(mnemonic));
+        return -1;
+    }
+
+    memset(mnemonic, 0, sizeof(mnemonic));
+    return 0;
+}

src/transport_frame.c

@@ -0,0 +1,104 @@
+#define _GNU_SOURCE
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+static int transport_read_full(int fd, void *buf, size_t len) {
+    unsigned char *p = (unsigned char *)buf;
+    size_t off = 0;
+
+    while (off < len) {
+        ssize_t n = read(fd, p + off, len - off);
+        if (n == 0) {
+            return -1;
+        }
+        if (n < 0) {
+            if (errno == EINTR) {
+                continue;
+            }
+            return -1;
+        }
+        off += (size_t)n;
+    }
+
+    return 0;
+}
+
+static int transport_write_full(int fd, const void *buf, size_t len) {
+    const unsigned char *p = (const unsigned char *)buf;
+    size_t off = 0;
+
+    while (off < len) {
+        ssize_t n = write(fd, p + off, len - off);
+        if (n < 0) {
+            if (errno == EINTR) {
+                continue;
+            }
+            return -1;
+        }
+        off += (size_t)n;
+    }
+
+    return 0;
+}
+
+int transport_send_framed(int fd, const char *payload) {
+    uint32_t len;
+    uint32_t be_len;
+
+    if (payload == NULL) {
+        return -1;
+    }
+
+    len = (uint32_t)strlen(payload);
+    be_len = htonl(len);
+
+    if (transport_write_full(fd, &be_len, sizeof(be_len)) != 0) {
+        return -1;
+    }
+    if (transport_write_full(fd, payload, len) != 0) {
+        return -1;
+    }
+
+    return 0;
+}
+
+int transport_recv_framed(int fd, char **out_payload, size_t max_size) {
+    uint32_t be_len;
+    uint32_t len;
+    char *payload;
+
+    if (out_payload == NULL || max_size == 0) {
+        return -1;
+    }
+
+    *out_payload = NULL;
+
+    if (transport_read_full(fd, &be_len, sizeof(be_len)) != 0) {
+        return -1;
+    }
+
+    len = ntohl(be_len);
+    if (len == 0 || len > max_size) {
+        return -1;
+    }
+
+    payload = (char *)malloc((size_t)len + 1U);
+    if (payload == NULL) {
+        return -1;
+    }
+
+    if (transport_read_full(fd, payload, len) != 0) {
+        free(payload);
+        return -1;
+    }
+
+    payload[len] = '\0';
+    *out_payload = payload;
+    return 0;
+}

tests/test.sh

@@ -0,0 +1,176 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+NSIGNER_BIN="${NSIGNER_BIN:-./build/nsigner}"
+socket_name=""
+
+if [[ ! -x "$NSIGNER_BIN" ]]; then
+  echo "[error] nsigner binary not found or not executable at: $NSIGNER_BIN"
+  echo "        Build it first with: make dev"
+  exit 1
+fi
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    -n|--name|--socket-name)
+      if [[ $# -lt 2 ]]; then
+        echo "[error] missing value for $1"
+        exit 1
+      fi
+      socket_name="$2"
+      shift 2
+      ;;
+    -h|--help)
+      echo "Usage: $0 [-n|--name|--socket-name <socket_name>]"
+      exit 0
+      ;;
+    *)
+      echo "[error] unknown argument: $1"
+      echo "Usage: $0 [-n|--name|--socket-name <socket_name>]"
+      exit 1
+      ;;
+  esac
+done
+
+echo "n_signer interactive smoke test"
+echo "Using binary: $NSIGNER_BIN"
+echo
+
+if [[ -z "$socket_name" ]]; then
+  default_socket=""
+  if [[ -r /proc/net/unix ]]; then
+    default_socket="$(awk '/@nsigner_/ {sub(/^@/, "", $8); print $8; exit}' /proc/net/unix || true)"
+  fi
+
+  if [[ -n "$default_socket" ]]; then
+    read -r -p "Signer socket name (without @) [${default_socket}]: " socket_name
+    socket_name="${socket_name:-$default_socket}"
+  else
+    read -r -p "Signer socket name (without @, e.g. nsigner_hairy_dog): " socket_name
+  fi
+fi
+
+if [[ -z "${socket_name}" ]]; then
+  echo "[error] socket name is required"
+  exit 1
+fi
+
+run_request() {
+  local req="$1"
+  "$NSIGNER_BIN" --socket-name "$socket_name" client "$req" || true
+}
+
+extract_result_string() {
+  sed -n 's/.*"result":"\([^"]*\)".*/\1/p'
+}
+
+echo
+echo "[1/7] get_public_key"
+req_get='{"id":"1","method":"get_public_key","params":[]}'
+resp_get="$(run_request "$req_get")"
+echo "request : $req_get"
+echo "response: $resp_get"
+pubkey="$(printf '%s' "$resp_get" | sed -n 's/.*"result":"\([0-9a-fA-F]\{64\}\)".*/\1/p')"
+if [[ -n "$pubkey" ]]; then
+  echo "pubkey  : $pubkey"
+else
+  echo "[warn] could not parse pubkey from response"
+fi
+
+echo
+echo "[2/7] sign_event"
+now_ts="$(date +%s)"
+event_json='{"kind":1,"content":"hello from tests/test.sh","tags":[],"created_at":__TS__}'
+event_json="${event_json/__TS__/${now_ts}}"
+escaped_event_json="${event_json//\"/\\\"}"
+req_sign="{\"id\":\"2\",\"method\":\"sign_event\",\"params\":[\"${escaped_event_json}\",{\"role\":\"main\"}]}"
+resp_sign="$(run_request "$req_sign")"
+echo "request : $req_sign"
+echo "response: $resp_sign"
+if printf '%s' "$resp_sign" | grep -q '"result"'; then
+  echo "[ok] sign_event returned result"
+else
+  echo "[warn] sign_event did not return result"
+fi
+
+echo
+echo "[3/7] sign_event with nostr_index=0"
+req_sign_idx="{\"id\":\"3\",\"method\":\"sign_event\",\"params\":[\"${escaped_event_json}\",{\"nostr_index\":0}]}"
+resp_sign_idx="$(run_request "$req_sign_idx")"
+echo "request : $req_sign_idx"
+echo "response: $resp_sign_idx"
+
+echo
+echo "[4/7] role selector error case (unknown role)"
+req_bad_role='{"id":"4","method":"sign_event","params":["{}",{"role":"does_not_exist"}]}'
+resp_bad_role="$(run_request "$req_bad_role")"
+echo "request : $req_bad_role"
+echo "response: $resp_bad_role"
+if printf '%s' "$resp_bad_role" | grep -q '"message":"unknown_role"'; then
+  echo "[ok] unknown role error name is unknown_role"
+else
+  echo "[warn] unknown role error name mismatch"
+fi
+
+echo
+echo "[5/7] NIP-04 self round-trip"
+if [[ -n "$pubkey" ]]; then
+  req_nip04_enc="{\"id\":\"5\",\"method\":\"nip04_encrypt\",\"params\":[\"${pubkey}\",\"hello_nip04_from_test_sh\"]}"
+  resp_nip04_enc="$(run_request "$req_nip04_enc")"
+  echo "request : $req_nip04_enc"
+  echo "response: $resp_nip04_enc"
+  cipher_nip04="$(printf '%s' "$resp_nip04_enc" | extract_result_string)"
+  if [[ -n "$cipher_nip04" ]]; then
+    req_nip04_dec="{\"id\":\"6\",\"method\":\"nip04_decrypt\",\"params\":[\"${pubkey}\",\"${cipher_nip04}\"]}"
+    resp_nip04_dec="$(run_request "$req_nip04_dec")"
+    echo "request : $req_nip04_dec"
+    echo "response: $resp_nip04_dec"
+    if printf '%s' "$resp_nip04_dec" | grep -q '"result":"hello_nip04_from_test_sh"'; then
+      echo "[ok] nip04 decrypt recovered plaintext"
+    else
+      echo "[warn] nip04 decrypt did not recover expected plaintext"
+    fi
+  else
+    echo "[warn] could not parse nip04 ciphertext"
+  fi
+else
+  echo "[warn] skipping nip04 test (missing pubkey)"
+fi
+
+echo
+echo "[6/7] NIP-44 self round-trip"
+if [[ -n "$pubkey" ]]; then
+  req_nip44_enc="{\"id\":\"7\",\"method\":\"nip44_encrypt\",\"params\":[\"${pubkey}\",\"hello_nip44_from_test_sh\"]}"
+  resp_nip44_enc="$(run_request "$req_nip44_enc")"
+  echo "request : $req_nip44_enc"
+  echo "response: $resp_nip44_enc"
+  cipher_nip44="$(printf '%s' "$resp_nip44_enc" | extract_result_string)"
+  if [[ -n "$cipher_nip44" ]]; then
+    req_nip44_dec="{\"id\":\"8\",\"method\":\"nip44_decrypt\",\"params\":[\"${pubkey}\",\"${cipher_nip44}\"]}"
+    resp_nip44_dec="$(run_request "$req_nip44_dec")"
+    echo "request : $req_nip44_dec"
+    echo "response: $resp_nip44_dec"
+    if printf '%s' "$resp_nip44_dec" | grep -q '"result":"hello_nip44_from_test_sh"'; then
+      echo "[ok] nip44 decrypt recovered plaintext"
+    else
+      echo "[warn] nip44 decrypt did not recover expected plaintext"
+    fi
+  else
+    echo "[warn] could not parse nip44 ciphertext"
+  fi
+else
+  echo "[warn] skipping nip44 test (missing pubkey)"
+fi
+
+echo
+echo "[7/7] list currently running signers"
+list_resp="$($NSIGNER_BIN list 2>&1 || true)"
+echo "$list_resp"
+if printf '%s' "$list_resp" | grep -q '^@nsigner'; then
+  echo "[ok] signer list contains nsigner entries"
+else
+  echo "[warn] no @nsigner entries found"
+fi
+
+echo
+echo "Smoke test complete."

tests/test_dispatcher.c

@@ -1,7 +1,460 @@
-#include "../src/dispatcher.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
 
-#include "../src/enforcement.h"
-#include "../src/role_table.h"
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+/* Register a nostr-index role if missing. Returns 0 on success, -1 on error. */
+int role_table_register_nostr_index(role_table_t *table, int nostr_index);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Derive key for exactly one role index. Returns 0 on success, -1 on error. */
+int crypto_derive_one(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic, int role_index);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <nostr_core/nostr_common.h>
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -63,8 +516,10 @@ int main(void) {
     role_entry_t ssh_role;
     mnemonic_state_t mnemonic;
     dispatcher_ctx_t dispatcher;
+    key_store_t key_store;
     const char *valid_12 = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about";
     char *resp;
+    int derived;
 
     role_table_init(&table);
 
@@ -74,30 +529,53 @@ int main(void) {
     role_table_add(&table, &main_role);
     role_table_add(&table, &ssh_role);
 
+    check_condition("role_table_register_nostr_index adds index 9",
+        role_table_register_nostr_index(&table, 9) == 0 && role_table_find_by_nostr_index(&table, 9) != NULL);
+
     mnemonic_init(&mnemonic);
     mnemonic_load(&mnemonic, valid_12);
 
-    dispatcher_init(&dispatcher, &table, &mnemonic);
+    memset(&key_store, 0, sizeof(key_store));
+    dispatcher_init(&dispatcher, &table, &mnemonic, &key_store);
 
-    /* 1. Valid get_public_key no selector -> default main, not_yet_derived */
+    derived = nostr_init();
+    check_condition("nostr_init succeeds", derived == 0);
+
+    derived = crypto_derive_all(&key_store, &table, &mnemonic);
+    check_condition("crypto_derive_all derives at least one key", derived >= 1);
+
+    {
+        role_entry_t *r9 = role_table_find_by_nostr_index(&table, 9);
+        int idx9 = (r9 != NULL) ? (int)(r9 - &table.entries[0]) : -1;
+
+        check_condition("new role idx9 exists before derive_one", idx9 >= 0);
+        if (idx9 >= 0) {
+            check_condition("crypto_derive_one derives newly registered role",
+                crypto_derive_one(&key_store, &table, &mnemonic, idx9) == 0 &&
+                table.entries[idx9].derived == 1 &&
+                crypto_get_pubkey_hex(&key_store, idx9) != NULL);
+        }
+    }
+
+    /* 1. Valid get_public_key no selector -> default main, real pubkey */
     resp = dispatcher_handle_request(&dispatcher,
         "{\"id\":\"1\",\"method\":\"get_public_key\",\"params\":[\"\"]}");
-    check_condition("get_public_key default role returns not_yet_derived",
-        response_has(resp, "\"id\":\"1\"") && response_has(resp, "\"result\":\"not_yet_derived\""));
+    check_condition("get_public_key default role returns derived hex",
+        response_has(resp, "\"id\":\"1\"") && !response_has(resp, "not_yet_derived") && response_has(resp, "\"result\":\""));
     free(resp);
 
     /* 2. sign_event with role main */
     resp = dispatcher_handle_request(&dispatcher,
-        "{\"id\":\"2\",\"method\":\"sign_event\",\"params\":[\"{}\",{\"role\":\"main\"}]}");
-    check_condition("sign_event with role=main returns stub",
-        response_has(resp, "\"id\":\"2\"") && response_has(resp, "\"result\":\"stub:sign_event_ok\""));
+        "{\"id\":\"2\",\"method\":\"sign_event\",\"params\":[\"{\\\"kind\\\":1,\\\"content\\\":\\\"hello\\\",\\\"tags\\\":[]}\",{\"role\":\"main\"}]}");
+    check_condition("sign_event with role=main returns signed event",
+        response_has(resp, "\"id\":\"2\"") && response_has(resp, "pubkey") && response_has(resp, "sig") && response_has(resp, "created_at"));
     free(resp);
 
     /* 3. sign_event with nostr_index 0 */
     resp = dispatcher_handle_request(&dispatcher,
-        "{\"id\":\"3\",\"method\":\"sign_event\",\"params\":[\"{}\",{\"nostr_index\":0}]}");
-    check_condition("sign_event with nostr_index=0 returns stub",
-        response_has(resp, "\"id\":\"3\"") && response_has(resp, "\"result\":\"stub:sign_event_ok\""));
+        "{\"id\":\"3\",\"method\":\"sign_event\",\"params\":[\"{\\\"kind\\\":1,\\\"content\\\":\\\"hello2\\\",\\\"tags\\\":[]}\",{\"nostr_index\":0}]}");
+    check_condition("sign_event with nostr_index=0 returns signed event",
+        response_has(resp, "\"id\":\"3\"") && response_has(resp, "pubkey") && response_has(resp, "sig") && response_has(resp, "created_at"));
     free(resp);
 
     /* 4. ambiguous selector role + nostr_index */
@@ -107,11 +585,11 @@ int main(void) {
         response_has(resp, "\"id\":\"4\"") && response_has(resp, "\"code\":1001"));
     free(resp);
 
-    /* 5. role not found */
+    /* 5. unknown role */
     resp = dispatcher_handle_request(&dispatcher,
         "{\"id\":\"5\",\"method\":\"sign_event\",\"params\":[\"{}\",{\"role\":\"nonexistent\"}]}");
-    check_condition("role not found returns 1002",
-        response_has(resp, "\"id\":\"5\"") && response_has(resp, "\"code\":1002"));
+    check_condition("unknown role returns 1002 with unknown_role",
+        response_has(resp, "\"id\":\"5\"") && response_has(resp, "\"code\":1002") && response_has(resp, "unknown_role"));
     free(resp);
 
     /* 6. purpose mismatch: sign_event against ssh role */
@@ -152,7 +630,10 @@ int main(void) {
         response_has(resp, "\"id\":\"10\"") && response_has(resp, "\"code\":-32601"));
     free(resp);
 
-    printf("%d/10 tests passed\n", g_passes);
+    crypto_wipe(&key_store);
+    nostr_cleanup();
 
-    return (g_passes == 10 && g_total == 10) ? 0 : 1;
+    printf("%d/%d tests passed\n", g_passes, g_total);
+
+    return (g_passes == g_total) ? 0 : 1;
 }

tests/test_enforcement.c

@@ -1,4 +1,452 @@
-#include "../src/enforcement.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <stdio.h>
 #include <string.h>

tests/test_integration.c

@@ -1,5 +1,455 @@
 #define _GNU_SOURCE
 
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
 #include <arpa/inet.h>
 #include <errno.h>
 #include <signal.h>
@@ -14,7 +464,8 @@
 #include <time.h>
 #include <unistd.h>
 
-#define SOCKET_NAME "nsigner"
+#define SOCKET_NAME_A "nsigner_test_run_a"
+#define SOCKET_NAME_B "nsigner_test_run_b"
 #define MAX_MSG_SIZE 65536
 
 static int g_failures = 0;
@@ -154,8 +605,8 @@ static int recv_framed(int fd, char **out_payload) {
     return 0;
 }
 
-static int request_roundtrip(const char *req, char **resp) {
-    int fd = connect_socket_retry(SOCKET_NAME, 5000);
+static int request_roundtrip_to(const char *socket_name, const char *req, char **resp) {
+    int fd = connect_socket_retry(socket_name, 5000);
     int rc;
 
     if (fd < 0) {
@@ -174,7 +625,8 @@ static int request_roundtrip(const char *req, char **resp) {
 int main(void) {
     int stdin_pipe[2];
     pid_t child;
-    const char *mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about\n\n";
+    pid_t child2;
+    const char *mnemonic = "\nabandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about\n";
     char *resp = NULL;
     int status;
 
@@ -199,25 +651,60 @@ int main(void) {
             close(null_fd);
         }
 
+        (void)setenv("NSIGNER_TEST_FORCE_PROMPT", "1", 1);
+        (void)setenv("NSIGNER_TEST_NONINTERACTIVE_PROMPT", "allow", 1);
+
         dup2(stdin_pipe[0], STDIN_FILENO);
         close(stdin_pipe[0]);
         close(stdin_pipe[1]);
 
-        execl("./build/nsigner", "./build/nsigner", (char *)NULL);
+        execl("./build/nsigner", "./build/nsigner", "--socket-name", SOCKET_NAME_A, (char *)NULL);
         _exit(127);
     }
 
     close(stdin_pipe[0]);
     if (write_full(stdin_pipe[1], mnemonic, strlen(mnemonic)) == 0) {
+
         check_condition("feed mnemonic to child stdin", 1);
     } else {
         check_condition("feed mnemonic to child stdin", 0);
     }
     close(stdin_pipe[1]);
 
-    sleep_ms(800);
+    {
+        int stdin_pipe2[2];
+        if (pipe(stdin_pipe2) != 0) {
+            perror("pipe2");
+            return 1;
+        }
+        child2 = fork();
+        if (child2 < 0) {
+            perror("fork2");
+            return 1;
+        }
+        if (child2 == 0) {
+            int null_fd = open("/dev/null", O_WRONLY);
+            if (null_fd >= 0) {
+                dup2(null_fd, STDOUT_FILENO);
+                dup2(null_fd, STDERR_FILENO);
+                close(null_fd);
+            }
+            (void)setenv("NSIGNER_TEST_FORCE_PROMPT", "1", 1);
+            (void)setenv("NSIGNER_TEST_HOTKEYS", "a", 1);
+            dup2(stdin_pipe2[0], STDIN_FILENO);
+            close(stdin_pipe2[0]);
+            close(stdin_pipe2[1]);
+            execl("./build/nsigner", "./build/nsigner", "--socket-name", SOCKET_NAME_B, (char *)NULL);
+            _exit(127);
+        }
+        close(stdin_pipe2[0]);
+        (void)write_full(stdin_pipe2[1], mnemonic, strlen(mnemonic));
+        close(stdin_pipe2[1]);
+    }
 
-    if (request_roundtrip("{\"id\":\"1\",\"method\":\"get_public_key\",\"params\":[\"\"]}", &resp) == 0) {
+    sleep_ms(1000);
+
+    if (request_roundtrip_to(SOCKET_NAME_A, "{\"id\":\"1\",\"method\":\"get_public_key\",\"params\":[\"\"]}", &resp) == 0) {
         check_condition("get_public_key response id", strstr(resp, "\"id\":\"1\"") != NULL);
         check_condition("get_public_key has result", strstr(resp, "\"result\":") != NULL);
     } else {
@@ -226,14 +713,81 @@ int main(void) {
     free(resp);
     resp = NULL;
 
-    if (request_roundtrip("{\"id\":\"2\",\"method\":\"sign_event\",\"params\":[\"{}\",{\"role\":\"main\"}]}", &resp) == 0) {
+    if (request_roundtrip_to(SOCKET_NAME_A, "{\"id\":\"2\",\"method\":\"sign_event\",\"params\":[\"{\\\"kind\\\":1,\\\"content\\\":\\\"hello\\\",\\\"tags\\\":[],\\\"created_at\\\":1700000000}\",{\"role\":\"main\"}]}", &resp) == 0) {
         check_condition("sign_event response id", strstr(resp, "\"id\":\"2\"") != NULL);
-        check_condition("sign_event stub result", strstr(resp, "stub:sign_event_ok") != NULL);
+        check_condition("sign_event has result", strstr(resp, "\"result\":") != NULL);
     } else {
         check_condition("sign_event request roundtrip", 0);
     }
     free(resp);
 
+
+    {
+        char *resp_a = NULL;
+        char *resp_b = NULL;
+        char pub_a[65] = {0};
+        char pub_b[65] = {0};
+        char cipher[2048] = {0};
+        char req[4096];
+        const char *p;
+
+        if (request_roundtrip_to(SOCKET_NAME_A, "{\"id\":\"3\",\"method\":\"get_public_key\",\"params\":[\"\"]}", &resp_a) == 0 &&
+            request_roundtrip_to(SOCKET_NAME_B, "{\"id\":\"4\",\"method\":\"get_public_key\",\"params\":[\"\"]}", &resp_b) == 0) {
+            p = strstr(resp_a, "\"result\":\"");
+            if (p) { p += 10; strncpy(pub_a, p, 64); pub_a[64]='\0'; }
+            p = strstr(resp_b, "\"result\":\"");
+            if (p) { p += 10; strncpy(pub_b, p, 64); pub_b[64]='\0'; }
+            check_condition("multi-instance distinct sockets respond", pub_a[0] && pub_b[0]);
+
+            snprintf(req, sizeof(req), "{\"id\":\"5\",\"method\":\"nip04_encrypt\",\"params\":[\"%s\",\"hello_nip04\"]}", pub_b);
+            free(resp_a); resp_a = NULL;
+            if (request_roundtrip_to(SOCKET_NAME_A, req, &resp_a) == 0) {
+                p = strstr(resp_a, "\"result\":\"");
+                if (p) {
+                    size_t i = 0;
+                    p += 10;
+                    while (p[i] && p[i] != '\"' && i < sizeof(cipher)-1) { cipher[i]=p[i]; i++; }
+                    cipher[i]='\0';
+                }
+                snprintf(req, sizeof(req), "{\"id\":\"6\",\"method\":\"nip04_decrypt\",\"params\":[\"%s\",\"%s\"]}", pub_a, cipher);
+                free(resp_b); resp_b = NULL;
+                if (request_roundtrip_to(SOCKET_NAME_B, req, &resp_b) == 0) {
+                    check_condition("nip04 round-trip plaintext recovered", strstr(resp_b, "hello_nip04") != NULL);
+                } else {
+                    check_condition("nip04 decrypt request roundtrip", 0);
+                }
+            } else {
+                check_condition("nip04 encrypt request roundtrip", 0);
+            }
+
+            memset(cipher, 0, sizeof(cipher));
+            snprintf(req, sizeof(req), "{\"id\":\"7\",\"method\":\"nip44_encrypt\",\"params\":[\"%s\",\"hello_nip44\"]}", pub_b);
+            free(resp_a); resp_a = NULL;
+            if (request_roundtrip_to(SOCKET_NAME_A, req, &resp_a) == 0) {
+                p = strstr(resp_a, "\"result\":\"");
+                if (p) {
+                    size_t i = 0;
+                    p += 10;
+                    while (p[i] && p[i] != '\"' && i < sizeof(cipher)-1) { cipher[i]=p[i]; i++; }
+                    cipher[i]='\0';
+                }
+                snprintf(req, sizeof(req), "{\"id\":\"8\",\"method\":\"nip44_decrypt\",\"params\":[\"%s\",\"%s\"]}", pub_a, cipher);
+                free(resp_b); resp_b = NULL;
+                if (request_roundtrip_to(SOCKET_NAME_B, req, &resp_b) == 0) {
+                    check_condition("nip44 round-trip plaintext recovered", strstr(resp_b, "hello_nip44") != NULL);
+                } else {
+                    check_condition("nip44 decrypt request roundtrip", 0);
+                }
+            } else {
+                check_condition("nip44 encrypt request roundtrip", 0);
+            }
+        } else {
+            check_condition("multi-instance public key requests", 0);
+        }
+        free(resp_a);
+        free(resp_b);
+    }
+
     if (kill(child, SIGTERM) == 0) {
         check_condition("send SIGTERM to child", 1);
     } else {
@@ -246,6 +800,9 @@ int main(void) {
         check_condition("child exited", 0);
     }
 
+    (void)kill(child2, SIGTERM);
+    (void)waitpid(child2, &status, 0);
+
     if (g_failures == 0) {
         printf("ALL TESTS PASSED\n");
         return 0;

tests/test_mnemonic.c

@@ -1,4 +1,452 @@
-#include "../src/mnemonic.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <stdio.h>
 #include <string.h>
@@ -46,6 +494,8 @@ int main(void) {
     const char *invalid_11 = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about";
     char invalid_25[MNEMONIC_MAX_LEN];
     const char *loaded_phrase;
+    char generated_12[MNEMONIC_MAX_LEN];
+    char generated_24[MNEMONIC_MAX_LEN];
     int rc;
 
     mnemonic_init(&state);
@@ -73,6 +523,22 @@ int main(void) {
     check_condition("reject invalid 25-word mnemonic", rc == -1);
     check_condition("state remains unloaded after invalid 25-word load", mnemonic_is_loaded(&state) == 0);
 
+    rc = mnemonic_generate(12, generated_12, sizeof(generated_12));
+    check_condition("mnemonic_generate(12) returns 0", rc == 0);
+    check_condition("mnemonic_generate(12) output non-empty", rc == 0 && generated_12[0] != '\0');
+    check_condition("load generated 12-word mnemonic", rc == 0 && mnemonic_load(&state, generated_12) == 0);
+    check_condition("generated 12 word_count == 12", mnemonic_is_loaded(&state) && state.word_count == 12);
+    mnemonic_unload(&state);
+
+    rc = mnemonic_generate(24, generated_24, sizeof(generated_24));
+    check_condition("mnemonic_generate(24) returns 0", rc == 0);
+    check_condition("mnemonic_generate(24) output non-empty", rc == 0 && generated_24[0] != '\0');
+    check_condition("load generated 24-word mnemonic", rc == 0 && mnemonic_load(&state, generated_24) == 0);
+    check_condition("generated 24 word_count == 24", mnemonic_is_loaded(&state) && state.word_count == 24);
+    mnemonic_unload(&state);
+
+    check_condition("two generated mnemonics differ", strcmp(generated_12, generated_24) != 0);
+
     if (g_failures == 0) {
         printf("ALL TESTS PASSED\n");
         return 0;

tests/test_policy.c

@@ -1,4 +1,458 @@
-#include "../src/policy.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy table entries. */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/* Insert an entry before the final catch-all rule. */
+int policy_table_insert_before_last(policy_table_t *table, const policy_entry_t *entry);
+
+/* Parse a --preapprove spec into a policy entry. */
+int parse_preapprove_spec(const char *spec, policy_entry_t *out_entry, int *out_nostr_index);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <stdio.h>
 #include <string.h>
@@ -46,7 +500,9 @@ static void add_single_entry(policy_table_t *table,
 
 int main(void) {
     policy_table_t table;
+    policy_entry_t parsed;
     int rc;
+    int parsed_nostr_index;
     uid_t uid = getuid();
     char same_uid[64];
     char other_uid[64];
@@ -54,74 +510,177 @@ int main(void) {
     (void)snprintf(same_uid, sizeof(same_uid), "uid:%u", (unsigned int)uid);
     (void)snprintf(other_uid, sizeof(other_uid), "uid:%u", (unsigned int)(uid + 1U));
 
-    policy_init_default(&table, uid);
-    rc = policy_check(&table, same_uid, "sign_event", "main", "nostr");
-    check_condition("policy_init_default allows same uid", rc == POLICY_ALLOW);
+    rc = parse_preapprove_spec("caller=uid:1000,role=main", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec accepts caller+role", rc == 0);
+    check_condition("parse_preapprove_spec caller set", strcmp(parsed.caller, "uid:1000") == 0);
+    check_condition("parse_preapprove_spec role set", strcmp(parsed.roles[0], "main") == 0);
+    check_condition("parse_preapprove_spec role_count=1", parsed.role_count == 1);
+    check_condition("parse_preapprove_spec prompt=never", parsed.prompt == PROMPT_NEVER);
+    check_condition("parse_preapprove_spec nostr_index unchanged for role", parsed_nostr_index == -1);
 
-    rc = policy_check(&table, other_uid, "sign_event", "main", "nostr");
-    check_condition("policy_init_default denies different uid", rc == POLICY_DENY);
+    rc = parse_preapprove_spec("caller=uid:1000,nostr_index=0", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec accepts caller+nostr_index", rc == 0);
+    check_condition("parse_preapprove_spec nostr_index=0 maps to main", strcmp(parsed.roles[0], "main") == 0);
+    check_condition("parse_preapprove_spec returns parsed nostr_index", parsed_nostr_index == 0);
+
+    rc = parse_preapprove_spec("caller=uid:1000,nostr_index=2", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec maps nonzero nostr_index role", strcmp(parsed.roles[0], "nostr_idx_2") == 0);
+    check_condition("parse_preapprove_spec stores nonzero nostr_index", parsed_nostr_index == 2);
+
+    rc = parse_preapprove_spec("role=main", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec rejects missing caller", rc == -1);
+    rc = parse_preapprove_spec("caller=uid:1000", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec rejects missing role and nostr_index", rc == -1);
+    rc = parse_preapprove_spec("caller=uid:1000,role=main,nostr_index=0", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec rejects both role and nostr_index", rc == -1);
+    rc = parse_preapprove_spec("caller=uid:1000,nostr_index=-1", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec rejects negative nostr_index", rc == -1);
+    rc = parse_preapprove_spec("caller=uid:1000,nostr_index=abc", &parsed, &parsed_nostr_index);
+    check_condition("parse_preapprove_spec rejects non-numeric nostr_index", rc == -1);
+
+    policy_init_default(&table, uid);
+    rc = policy_check(&table, same_uid, "sign_event", "main", "nostr", NULL);
+    check_condition("policy_init_default prompts same uid", rc == POLICY_PROMPT);
+
+    rc = policy_check(&table, other_uid, "sign_event", "main", "nostr", NULL);
+    check_condition("policy_init_default prompts different uid", rc == POLICY_PROMPT);
+
+    /* Insert before catch-all: matching caller allowed, non-matching still prompted */
+    policy_table_init(&table);
+    add_single_entry(&table, "*", NULL, NULL, NULL, PROMPT_EVERY_REQUEST);
+    {
+        policy_entry_t grant;
+        memset(&grant, 0, sizeof(grant));
+        strncpy(grant.caller, "uid:1000", sizeof(grant.caller) - 1);
+        strncpy(grant.roles[0], "main", sizeof(grant.roles[0]) - 1);
+        grant.role_count = 1;
+        grant.prompt = PROMPT_NEVER;
+        rc = policy_table_insert_before_last(&table, &grant);
+        check_condition("policy_table_insert_before_last succeeds", rc == 0);
+    }
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
+    check_condition("insert_before_last matching caller returns POLICY_ALLOW", rc == POLICY_ALLOW);
+    rc = policy_check(&table, "uid:2000", "sign_event", "main", "nostr", NULL);
+    check_condition("insert_before_last non-matching caller returns POLICY_PROMPT", rc == POLICY_PROMPT);
+
+    /* Preapprove parse + insert: matching caller allowed, non-matching prompted */
+    policy_init_default(&table, uid);
+    rc = parse_preapprove_spec("caller=uid:1000,role=main", &parsed, &parsed_nostr_index);
+    check_condition("preapprove parse for policy insert succeeds", rc == 0);
+    rc = policy_table_insert_before_last(&table, &parsed);
+    check_condition("preapprove insert_before_last succeeds", rc == 0);
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
+    check_condition("preapprove allows matching caller+role", rc == POLICY_ALLOW);
+    rc = policy_check(&table, "uid:2000", "sign_event", "main", "nostr", NULL);
+    check_condition("preapprove leaves non-matching caller at POLICY_PROMPT", rc == POLICY_PROMPT);
 
     /* Exact caller, verb, role, purpose + never => allow */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "sign_event", "main", "nostr", PROMPT_NEVER);
-    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
     check_condition("exact match returns POLICY_ALLOW", rc == POLICY_ALLOW);
 
     /* Wildcard caller + deny => deny */
     policy_table_init(&table);
     add_single_entry(&table, "*", "sign_event", "main", "nostr", PROMPT_DENY);
-    rc = policy_check(&table, "uid:2000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:2000", "sign_event", "main", "nostr", NULL);
     check_condition("wildcard caller with deny returns POLICY_DENY", rc == POLICY_DENY);
 
     /* Caller no match => POLICY_NO_MATCH */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "sign_event", "main", "nostr", PROMPT_NEVER);
-    rc = policy_check(&table, "uid:9999", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:9999", "sign_event", "main", "nostr", NULL);
     check_condition("caller mismatch returns POLICY_NO_MATCH", rc == POLICY_NO_MATCH);
 
     /* Verb not in list => no match */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "get_public_key", "main", "nostr", PROMPT_NEVER);
-    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
     check_condition("verb mismatch returns POLICY_NO_MATCH", rc == POLICY_NO_MATCH);
 
     /* Role not in list => no match */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "sign_event", "throwaway", "nostr", PROMPT_NEVER);
-    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
     check_condition("role mismatch returns POLICY_NO_MATCH", rc == POLICY_NO_MATCH);
 
     /* Purpose not in list => no match */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "sign_event", "main", "bitcoin", PROMPT_NEVER);
-    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
     check_condition("purpose mismatch returns POLICY_NO_MATCH", rc == POLICY_NO_MATCH);
 
     /* Empty verbs list means all verbs */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", NULL, "main", "nostr", PROMPT_NEVER);
-    rc = policy_check(&table, "uid:1000", "nip44_encrypt", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "nip44_encrypt", "main", "nostr", NULL);
     check_condition("empty verbs list matches any verb", rc == POLICY_ALLOW);
 
     /* prompt=first_per_boot => POLICY_PROMPT */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "sign_event", "main", "nostr", PROMPT_FIRST_PER_BOOT);
-    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
     check_condition("first_per_boot returns POLICY_PROMPT", rc == POLICY_PROMPT);
 
     /* prompt=every_request => POLICY_PROMPT */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "sign_event", "main", "nostr", PROMPT_EVERY_REQUEST);
-    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
     check_condition("every_request returns POLICY_PROMPT", rc == POLICY_PROMPT);
 
     /* First matching entry wins */
     policy_table_init(&table);
     add_single_entry(&table, "uid:1000", "sign_event", "main", "nostr", PROMPT_DENY);
     add_single_entry(&table, "uid:1000", "sign_event", "main", "nostr", PROMPT_NEVER);
-    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr");
+    rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", NULL);
     check_condition("first matching entry wins", rc == POLICY_DENY);
 
+    /* Verify out_source for preapprove, session-grant, and default catch-all */
+    policy_table_init(&table);
+    {
+        policy_entry_t pre;
+        policy_entry_t sess;
+        policy_entry_t prompt_all;
+        policy_source_t src = POLICY_SOURCE_DEFAULT;
+
+        memset(&pre, 0, sizeof(pre));
+        strncpy(pre.caller, "uid:1000", sizeof(pre.caller) - 1);
+        strncpy(pre.roles[0], "main", sizeof(pre.roles[0]) - 1);
+        pre.role_count = 1;
+        pre.prompt = PROMPT_NEVER;
+        pre.source = POLICY_SOURCE_PREAPPROVE;
+        rc = policy_table_add(&table, &pre);
+        check_condition("source test preapprove entry add", rc == 0);
+
+        memset(&sess, 0, sizeof(sess));
+        strncpy(sess.caller, "uid:1001", sizeof(sess.caller) - 1);
+        strncpy(sess.roles[0], "main", sizeof(sess.roles[0]) - 1);
+        sess.role_count = 1;
+        sess.prompt = PROMPT_NEVER;
+        sess.source = POLICY_SOURCE_SESSION_GRANT;
+        rc = policy_table_add(&table, &sess);
+        check_condition("source test session entry add", rc == 0);
+
+        memset(&prompt_all, 0, sizeof(prompt_all));
+        strncpy(prompt_all.caller, "*", sizeof(prompt_all.caller) - 1);
+        prompt_all.prompt = PROMPT_EVERY_REQUEST;
+        prompt_all.source = POLICY_SOURCE_DEFAULT;
+        rc = policy_table_add(&table, &prompt_all);
+        check_condition("source test default catch-all add", rc == 0);
+
+        src = POLICY_SOURCE_DEFAULT;
+        rc = policy_check(&table, "uid:1000", "sign_event", "main", "nostr", &src);
+        check_condition("policy_check reports preapprove source", rc == POLICY_ALLOW && src == POLICY_SOURCE_PREAPPROVE);
+
+        src = POLICY_SOURCE_DEFAULT;
+        rc = policy_check(&table, "uid:1001", "sign_event", "main", "nostr", &src);
+        check_condition("policy_check reports session-grant source", rc == POLICY_ALLOW && src == POLICY_SOURCE_SESSION_GRANT);
+
+        src = POLICY_SOURCE_PREAPPROVE;
+        rc = policy_check(&table, "uid:9999", "sign_event", "main", "nostr", &src);
+        check_condition("policy_check resets source for prompt/default", rc == POLICY_PROMPT && src == POLICY_SOURCE_DEFAULT);
+    }
+
     printf("%d/%d tests passed\n", g_passes, g_total);
     return (g_passes == g_total) ? 0 : 1;
 }

tests/test_role_table.c

@@ -1,4 +1,455 @@
-#include "../src/role_table.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+/* Register a nostr-index role if missing. Returns 0 on success, -1 on error. */
+int role_table_register_nostr_index(role_table_t *table, int nostr_index);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <stdio.h>
 #include <string.h>
@@ -90,40 +541,28 @@ int main(void) {
     rc = role_table_add(&table, &e_main);
     check_condition("duplicate name rejection returns -2", rc == -2);
 
+    role_table_init(&table);
+    rc = role_table_register_nostr_index(&table, 7);
+    check_condition("register nostr_index=7 returns 0", rc == 0);
+    found = role_table_find_by_nostr_index(&table, 7);
+    check_condition("register nostr_index=7 creates role", found != NULL);
+    check_condition("registered role name is nostr_idx_7", found != NULL && strcmp(found->name, "nostr_idx_7") == 0);
+    check_condition("registered role purpose nostr", found != NULL && found->purpose == PURPOSE_NOSTR);
+    check_condition("registered role curve secp256k1", found != NULL && found->curve == CURVE_SECP256K1);
+    check_condition("registered role selector type nostr_index", found != NULL && found->selector_type == SELECTOR_NOSTR_INDEX);
+
+    rc = role_table_register_nostr_index(&table, 7);
+    check_condition("register nostr_index=7 idempotent second call", rc == 0);
+    check_condition("register nostr_index=7 idempotent no duplicate", table.count == 1);
+
     role_table_init(&table);
     for (i = 0; i < ROLE_TABLE_MAX_ENTRIES; ++i) {
-        role_entry_t e;
-        char name_buf[ROLE_NAME_MAX];
-
-        memset(&e, 0, sizeof(e));
-        snprintf(name_buf, sizeof(name_buf), "role_%d", i);
-        strncpy(e.name, name_buf, sizeof(e.name) - 1);
-        strncpy(e.purpose_str, "nostr", sizeof(e.purpose_str) - 1);
-        strncpy(e.curve_str, "secp256k1", sizeof(e.curve_str) - 1);
-        e.purpose = PURPOSE_NOSTR;
-        e.curve = CURVE_SECP256K1;
-        e.selector_type = SELECTOR_NOSTR_INDEX;
-        e.nostr_index = i;
-
-        rc = role_table_add(&table, &e);
-        check_condition("fill table role add returns 0", rc == 0);
+        rc = role_table_register_nostr_index(&table, i);
+        check_condition("fill table via register_nostr_index returns 0", rc == 0);
     }
 
-    {
-        role_entry_t overflow;
-
-        memset(&overflow, 0, sizeof(overflow));
-        strncpy(overflow.name, "overflow", sizeof(overflow.name) - 1);
-        strncpy(overflow.purpose_str, "nostr", sizeof(overflow.purpose_str) - 1);
-        strncpy(overflow.curve_str, "secp256k1", sizeof(overflow.curve_str) - 1);
-        overflow.purpose = PURPOSE_NOSTR;
-        overflow.curve = CURVE_SECP256K1;
-        overflow.selector_type = SELECTOR_NOSTR_INDEX;
-        overflow.nostr_index = 999;
-
-        rc = role_table_add(&table, &overflow);
-        check_condition("table full rejection returns -1", rc == -1);
-    }
+    rc = role_table_register_nostr_index(&table, ROLE_TABLE_MAX_ENTRIES + 7);
+    check_condition("register_nostr_index table full returns -1", rc == -1);
 
     if (g_failures == 0) {
         printf("ALL TESTS PASSED\n");

tests/test_selector.c

@@ -1,4 +1,452 @@
-#include "../src/selector.h"
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
 
 #include <stdio.h>
 #include <string.h>

tests/test_socket_name.c

@@ -0,0 +1,499 @@
+/* NSIGNER_HEADERLESS_DECLS_BEGIN */
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <cJSON.h>
+
+/* from secure_mem.h */
+
+
+/*
+ * Secure memory buffer — mlock'd, zeroized on free.
+ * Used for mnemonic phrases, private keys, and any sensitive material.
+ */
+typedef struct {
+    void *data;       /* pointer to locked allocation */
+    size_t size;      /* usable size in bytes */
+    int locked;       /* 1 if mlock succeeded */
+} secure_buf_t;
+
+/* Allocate a secure buffer of `size` bytes. Returns 0 on success, -1 on failure. */
+int secure_buf_alloc(secure_buf_t *buf, size_t size);
+
+/* Zeroize and free a secure buffer. Always succeeds (idempotent). */
+void secure_buf_free(secure_buf_t *buf);
+
+/* Zeroize `len` bytes at `ptr` in a way the compiler cannot optimize away. */
+void secure_memzero(void *ptr, size_t len);
+
+
+/* from mnemonic.h */
+
+
+/* Maximum mnemonic length: 24 words * 10 chars avg + spaces + null = 256 is safe */
+#define MNEMONIC_MAX_LEN 256
+
+/*
+ * Mnemonic state — holds the loaded mnemonic in secure memory.
+ * Only one mnemonic is active at a time per process.
+ */
+typedef struct {
+    secure_buf_t buf;       /* secure storage for the mnemonic string */
+    int loaded;             /* 1 if a mnemonic is currently loaded */
+    int word_count;         /* 12, 15, 18, 21, or 24 */
+} mnemonic_state_t;
+
+/* Initialize mnemonic state (must be called before use). */
+void mnemonic_init(mnemonic_state_t *state);
+
+/* Load a mnemonic string into secure memory. Validates word count (12/15/18/21/24).
+ * Returns 0 on success, -1 on invalid input, -2 on memory error. */
+int mnemonic_load(mnemonic_state_t *state, const char *phrase);
+
+/* Zeroize and unload the mnemonic. Idempotent. */
+void mnemonic_unload(mnemonic_state_t *state);
+
+/* Check if a mnemonic is currently loaded. */
+int mnemonic_is_loaded(const mnemonic_state_t *state);
+
+/* Get the mnemonic string (only valid while loaded). Returns NULL if not loaded. */
+const char *mnemonic_get_phrase(const mnemonic_state_t *state);
+
+/* Generate a new BIP-39 mnemonic phrase (12/15/18/21/24 words) into out.
+ * Returns 0 on success, -1 on invalid arguments or generation failure. */
+int mnemonic_generate(int word_count, char *out, size_t out_len);
+
+
+/* from role_table.h */
+
+
+/* Maximum limits */
+#define ROLE_NAME_MAX 64
+#define ROLE_PATH_MAX 128
+#define ROLE_PURPOSE_MAX 32
+#define ROLE_CURVE_MAX 16
+#define ROLE_PUBKEY_HEX_MAX 66 /* 64 hex chars + null + pad */
+#define ROLE_TABLE_MAX_ENTRIES 256
+
+/* Purpose enum for fast comparison (string form kept for config/display) */
+typedef enum {
+    PURPOSE_NOSTR = 0,
+    PURPOSE_BITCOIN,
+    PURPOSE_SSH,
+    PURPOSE_AGE,
+    PURPOSE_FIPS,
+    PURPOSE_UNKNOWN
+} role_purpose_t;
+
+/* Curve enum */
+typedef enum {
+    CURVE_SECP256K1 = 0,
+    CURVE_ED25519,
+    CURVE_X25519,
+    CURVE_UNKNOWN
+} role_curve_t;
+
+/* Selector type — how this role's key is addressed */
+typedef enum {
+    SELECTOR_NOSTR_INDEX, /* uses nostr_index shorthand */
+    SELECTOR_ROLE_PATH    /* uses explicit full path */
+} role_selector_type_t;
+
+/* A single role entry */
+typedef struct {
+    char name[ROLE_NAME_MAX];
+    char purpose_str[ROLE_PURPOSE_MAX];
+    char curve_str[ROLE_CURVE_MAX];
+    role_purpose_t purpose;
+    role_curve_t curve;
+    role_selector_type_t selector_type;
+    int nostr_index;                         /* valid if selector_type == SELECTOR_NOSTR_INDEX */
+    char role_path[ROLE_PATH_MAX];           /* valid if selector_type == SELECTOR_ROLE_PATH */
+    char pubkey_hex[ROLE_PUBKEY_HEX_MAX];    /* filled after derivation, empty until then */
+    int derived;                             /* 1 if pubkey_hex has been populated */
+} role_entry_t;
+
+/* The role table */
+typedef struct {
+    role_entry_t entries[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} role_table_t;
+
+/* Initialize an empty role table */
+void role_table_init(role_table_t *table);
+
+/* Add a role entry. Returns 0 on success, -1 if table full, -2 if name duplicate. */
+int role_table_add(role_table_t *table, const role_entry_t *entry);
+
+/* Find a role by name. Returns pointer to entry or NULL. */
+role_entry_t *role_table_find_by_name(role_table_t *table, const char *name);
+
+/* Find a role by nostr_index. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_nostr_index(role_table_t *table, int index);
+
+/* Find a role by role_path. Returns pointer or NULL. */
+role_entry_t *role_table_find_by_path(role_table_t *table, const char *path);
+
+/* Get the default role (named "main"). Returns pointer or NULL if no "main" role. */
+role_entry_t *role_table_get_default(role_table_t *table);
+
+/* Parse purpose string to enum */
+role_purpose_t role_purpose_from_str(const char *s);
+
+/* Parse curve string to enum */
+role_curve_t role_curve_from_str(const char *s);
+
+/* Purpose enum to string */
+const char *role_purpose_to_str(role_purpose_t p);
+
+/* Curve enum to string */
+const char *role_curve_to_str(role_curve_t c);
+
+
+/* from selector.h */
+
+
+/* Error codes for selector resolution */
+#define SELECTOR_OK                 0
+#define SELECTOR_ERR_AMBIGUOUS     -1   /* multiple selectors specified */
+#define SELECTOR_ERR_NOT_FOUND     -2   /* no matching role in table */
+#define SELECTOR_ERR_NO_DEFAULT    -3   /* no selector given and no "main" role exists */
+
+/* Parsed selector from a request's options object */
+typedef struct {
+    int has_role;          /* 1 if "role" field was present */
+    char role_name[ROLE_NAME_MAX];
+
+    int has_nostr_index;   /* 1 if "nostr_index" field was present */
+    int nostr_index;
+
+    int has_role_path;     /* 1 if "role_path" field was present */
+    char role_path[ROLE_PATH_MAX];
+} selector_request_t;
+
+/* Initialize a selector request (all fields zeroed/unset) */
+void selector_request_init(selector_request_t *req);
+
+/*
+ * Resolve a selector request against the role table.
+ * On success (returns SELECTOR_OK), *out points to the matched role_entry_t.
+ * On failure, returns one of the SELECTOR_ERR_* codes and *out is NULL.
+ */
+int selector_resolve(const selector_request_t *req, role_table_t *table, role_entry_t **out);
+
+/*
+ * Return a human-readable error string for a selector error code.
+ */
+const char *selector_strerror(int err);
+
+
+/* from enforcement.h */
+
+
+/* Error codes */
+#define ENFORCE_OK                0
+#define ENFORCE_ERR_PURPOSE      -1 /* purpose mismatch */
+#define ENFORCE_ERR_CURVE        -2 /* curve mismatch */
+#define ENFORCE_ERR_UNKNOWN_VERB -3 /* verb not recognized */
+
+/* Known verbs */
+#define VERB_SIGN_EVENT     "sign_event"
+#define VERB_GET_PUBLIC_KEY "get_public_key"
+#define VERB_NIP44_ENCRYPT  "nip44_encrypt"
+#define VERB_NIP44_DECRYPT  "nip44_decrypt"
+#define VERB_NIP04_ENCRYPT  "nip04_encrypt"
+#define VERB_NIP04_DECRYPT  "nip04_decrypt"
+
+/*
+ * Check whether `verb` is allowed to execute against `role`.
+ * Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
+ *
+ * The enforcement rules are:
+ *   - All nostr verbs (sign_event, get_public_key, nip44_*, nip04_*) require:
+ *     purpose == PURPOSE_NOSTR and curve == CURVE_SECP256K1
+ *   - Unknown verbs return ENFORCE_ERR_UNKNOWN_VERB (fail-closed).
+ */
+int enforce_verb_role(const char *verb, const role_entry_t *role);
+
+/*
+ * Return a human-readable error string for an enforcement error code.
+ */
+const char *enforce_strerror(int err);
+
+
+/* from policy.h */
+
+
+#define POLICY_MAX_ENTRIES    32
+#define POLICY_MAX_VERBS      16
+#define POLICY_MAX_ROLES      16
+#define POLICY_MAX_PURPOSES   8
+#define POLICY_VERB_MAX_LEN   32
+#define POLICY_CALLER_MAX_LEN 64
+
+/* Prompt behavior */
+typedef enum {
+    PROMPT_NEVER = 0,
+    PROMPT_FIRST_PER_BOOT,
+    PROMPT_EVERY_REQUEST,
+    PROMPT_DENY
+} prompt_mode_t;
+
+typedef enum {
+    POLICY_SOURCE_DEFAULT = 0,   /* the catch-all entry */
+    POLICY_SOURCE_PREAPPROVE,    /* from --preapprove CLI flag */
+    POLICY_SOURCE_SESSION_GRANT  /* from prompt [a] during session */
+} policy_source_t;
+
+/* A single policy entry */
+typedef struct {
+    char caller[POLICY_CALLER_MAX_LEN];   /* e.g. "uid:1000" or "*" for any */
+    char verbs[POLICY_MAX_VERBS][POLICY_VERB_MAX_LEN];
+    int verb_count;
+    char roles[POLICY_MAX_ROLES][ROLE_NAME_MAX];
+    int role_count;
+    char purposes[POLICY_MAX_PURPOSES][ROLE_PURPOSE_MAX];
+    int purpose_count;
+    prompt_mode_t prompt;
+    policy_source_t source;
+} policy_entry_t;
+
+/* Policy table */
+typedef struct {
+    policy_entry_t entries[POLICY_MAX_ENTRIES];
+    int count;
+} policy_table_t;
+
+/* Policy check result */
+#define POLICY_ALLOW     0
+#define POLICY_DENY     -1
+#define POLICY_PROMPT   -2   /* would need user confirmation */
+#define POLICY_NO_MATCH -3   /* no policy entry matched (fail-closed = deny) */
+
+/* Initialize policy table */
+void policy_table_init(policy_table_t *table);
+
+/* Initialize default policy: allow same-uid, deny others */
+void policy_init_default(policy_table_t *table, uid_t owner_uid);
+
+/* Add a policy entry. Returns 0 on success, -1 if full. */
+int policy_table_add(policy_table_t *table, const policy_entry_t *entry);
+
+/*
+ * Check whether caller_id is allowed to invoke `verb` on `role_name` with given `purpose`.
+ * Returns POLICY_ALLOW, POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH.
+ */
+int policy_check(const policy_table_t *table, const char *caller_id,
+                 const char *verb, const char *role_name, const char *purpose,
+                 policy_source_t *out_source);
+
+/* Parse prompt mode from string */
+prompt_mode_t prompt_mode_from_str(const char *s);
+
+/* Prompt mode to string */
+const char *prompt_mode_to_str(prompt_mode_t m);
+
+
+/* from crypto.h */
+
+
+/* Per-role derived key material (stored in secure memory) */
+typedef struct {
+    secure_buf_t private_key;  /* 32 bytes, mlock'd */
+    unsigned char public_key[32];
+    char pubkey_hex[65];       /* 64 hex chars + null */
+    char npub[128];            /* bech32 npub */
+    int valid;
+} derived_key_t;
+
+/* Key store — holds derived keys for all roles */
+typedef struct {
+    derived_key_t keys[ROLE_TABLE_MAX_ENTRIES];
+    int count;
+} key_store_t;
+
+/* Derive keys for all roles in the table using the loaded mnemonic.
+ * Populates key_store and sets role->pubkey_hex and role->derived for each role.
+ * Only derives for roles with purpose=nostr and curve=secp256k1 (for now).
+ * Returns number of keys derived, or -1 on error. */
+int crypto_derive_all(key_store_t *store, role_table_t *table, const mnemonic_state_t *mnemonic);
+
+/* Get the derived private key for a role (by table index). Returns NULL if not derived. */
+const unsigned char *crypto_get_private_key(const key_store_t *store, int role_index);
+
+/* Get the derived public key hex for a role. Returns NULL if not derived. */
+const char *crypto_get_pubkey_hex(const key_store_t *store, int role_index);
+
+/* Sign a Nostr event. event_json is the unsigned event JSON string.
+ * Returns a newly-allocated string containing the signed event JSON, or NULL on error.
+ * Caller must free() the returned string. */
+char *crypto_sign_event(const key_store_t *store, int role_index, const char *event_json);
+
+/* Zeroize all derived keys in the store. */
+void crypto_wipe(key_store_t *store);
+
+
+/* from dispatcher.h */
+
+
+/* Dispatcher context — holds references to shared state */
+typedef struct {
+    role_table_t *role_table;
+    mnemonic_state_t *mnemonic;
+    key_store_t *key_store;
+} dispatcher_ctx_t;
+
+/* Initialize dispatcher context */
+void dispatcher_init(dispatcher_ctx_t *ctx, role_table_t *table, mnemonic_state_t *mnemonic, key_store_t *key_store);
+
+/*
+ * Process a JSON-RPC request string and produce a JSON-RPC response string.
+ *
+ * The caller owns the returned string and must free() it.
+ * Returns NULL only on catastrophic allocation failure.
+ *
+ * Response format on success:
+ *   { "id": "...", "result": "..." }
+ *
+ * Response format on error:
+ *   { "id": "...", "error": { "code": <int>, "message": "..." } }
+ *
+ * Error codes:
+ *   -32700  Parse error (invalid JSON)
+ *   -32600  Invalid request (missing id/method/params)
+ *   -32601  Method not found (unknown verb after enforcement)
+ *   -32602  Invalid params
+ *   1001    ambiguous_role_selector
+ *   1002    role_not_found
+ *   1003    no_default_role
+ *   1004    purpose_mismatch
+ *   1005    curve_mismatch
+ *   1006    mnemonic_not_loaded
+ */
+char *dispatcher_handle_request(dispatcher_ctx_t *ctx, const char *json_request);
+
+
+/* from server.h */
+
+
+#define SERVER_SOCKET_NAME_MAX 108
+#define SERVER_MAX_MSG_SIZE    65536
+
+/* Caller identity */
+typedef struct {
+    uid_t uid;
+    gid_t gid;
+    pid_t pid;
+    char caller_id[64];  /* "uid:<n>" */
+} caller_identity_t;
+
+/* Server context */
+typedef struct {
+    char socket_name[SERVER_SOCKET_NAME_MAX]; /* abstract namespace name (without \0 prefix) */
+    char last_error[256];
+    int listen_fd;
+    int running;
+    dispatcher_ctx_t *dispatcher;
+    policy_table_t *policy;
+    int socket_name_explicit;
+} server_ctx_t;
+
+/* Initialize server context. socket_name is the abstract namespace name (e.g. "nsigner").
+ * socket_name_explicit should be non-zero when provided via --socket-name override. */
+void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
+                 dispatcher_ctx_t *dispatcher, policy_table_t *policy);
+
+/* Start listening. Returns 0 on success, -1 on error. */
+int server_start(server_ctx_t *ctx);
+
+/* Get human-readable description of last server error. */
+const char *server_last_error(const server_ctx_t *ctx);
+
+/* Handle one pending connection (non-blocking). Returns 1 if handled, 0 if nothing pending, -1 on error.
+ * activity_cb is called with a description string for the TUI activity log. */
+typedef void (*server_activity_cb)(const char *message, void *user_data);
+int server_handle_one(server_ctx_t *ctx, server_activity_cb cb, void *cb_data);
+
+/* Stop server and close socket */
+void server_stop(server_ctx_t *ctx);
+
+/* Extract caller identity from connected fd */
+int server_get_caller(int fd, caller_identity_t *out);
+
+
+/* from socket_name.h */
+
+
+/*
+ * Generate random socket name in format: nsigner_<word1>_<word2>
+ * Returns 0 on success, -1 on error.
+ */
+int socket_name_random(char *out, size_t out_len);
+
+
+/* from main.h */
+/*
+ * nsigner main header - version information
+ *
+ * Version macros are auto-updated by increment_and_push.sh.
+ */
+
+
+/* Version information (auto-updated by build/version tooling) */
+#define NSIGNER_VERSION_MAJOR 0
+#define NSIGNER_VERSION_MINOR 0
+#define NSIGNER_VERSION_PATCH 2
+#define NSIGNER_VERSION "v0.0.2"
+
+
+/* NSIGNER_HEADERLESS_DECLS_END */
+
+#include <stdio.h>
+#include <string.h>
+
+static int g_failures = 0;
+
+static void check_condition(const char *name, int condition) {
+    if (condition) {
+        printf("PASS: %s\n", name);
+    } else {
+        printf("FAIL: %s\n", name);
+        g_failures++;
+    }
+}
+
+int main(void) {
+    char a[128];
+    char b[128];
+
+    memset(a, 0, sizeof(a));
+    memset(b, 0, sizeof(b));
+
+    check_condition("socket_name_random(a) succeeds", socket_name_random(a, sizeof(a)) == 0);
+    check_condition("socket_name_random(b) succeeds", socket_name_random(b, sizeof(b)) == 0);
+
+    check_condition("name a starts with nsigner_", strncmp(a, "nsigner_", 8) == 0);
+    check_condition("name b starts with nsigner_", strncmp(b, "nsigner_", 8) == 0);
+
+    {
+        const char *suffix = a + 8;
+        const char *underscore = strchr(suffix, '_');
+        check_condition("name a contains second underscore", underscore != NULL && underscore > suffix && underscore[1] != '\0');
+    }
+
+    {
+        const char *suffix = b + 8;
+        const char *underscore = strchr(suffix, '_');
+        check_condition("name b contains second underscore", underscore != NULL && underscore > suffix && underscore[1] != '\0');
+    }
+
+    check_condition("two generated names are typically different", strcmp(a, b) != 0);
+
+    if (g_failures == 0) {
+        printf("ALL TESTS PASSED\n");
+        return 0;
+    }
+
+    printf("TESTS FAILED: %d\n", g_failures);
+    return 1;
+}