fips/CHANGELOG.md

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[Unreleased]

Added

• PR-REVIEW.md — the 13-criteria PR review checklist the maintainer runs against every incoming PR, published at the repo root so contributors can run the same pass on their own change (directly or by handing the document to a coding agent) before opening. Linked from CONTRIBUTING.md under "Submitting pull requests" and "Further reading". Running the checklist before opening surfaces problems that would otherwise come back as review comments, saving a round trip.

Changed

• Sidecar example (examples/sidecar-nostr-relay): udp.mtu is now overridable via the FIPS_UDP_MTU environment variable, defaulting to 1472 (preserving prior behavior). Plumbed through docker-compose.yml and documented in the README env-var table. Annotated the static-CI node template mtu: 1472 literal with the same Docker-bridge rationale and a pointer at the daemon's 1280 default.
• Overhauled CONTRIBUTING.md: replaced generic Rust-template framing with a FIPS-specific entry point covering the four-layer architecture, branch model and PR-target selection, structured bug reporting, scope discipline and local-CI requirements, an AI coding assistant policy, and project communication channels. Added docs/branching.md as the long-form companion covering the release workflow, version conventions, and merge-direction rationale.
• CI and release-publish workflows hardened:
  • ci.yml declares a top-level concurrency block keyed on (workflow, ref) with cancel-in-progress: true. Force-pushes and rapid successive pushes to the same ref now retire any in-flight run rather than letting superseded and current-tip runs both burn runner minutes.
  • aur-publish.yml rewritten to fetch the upstream source tarball and compute its b2sum in CI, then patch pkgver and the b2sums SKIP placeholder in PKGBUILD in-place. Previously updpkgsums: true downloaded the tarball into the AUR working tree, where it was rejected by AUR's 488 KiB max-blob hook — silently no-op'ing the v0.3.0 stable AUR push. fips.sysusers / fips.tmpfiles asset b2sums are recomputed in the same step to stay in sync with the local files. workflow_dispatch gains a tag input so historical release tags can be re-published manually, and continue-on-error: true is dropped so future regressions surface in CI.
  • New aur-publish-git.yml workflow for the fips-git VCS PKGBUILD, triggered on master pushes touching PKGBUILD-git or companion files plus workflow_dispatch. pkgver is computed at build time by the PKGBUILD's pkgver() function, so this workflow is not tied to release tags.
  • Tag-triggered package-* release-build workflows remain untouched.

Fixed

• Coord cache invalidation made surgical at parent-position-change and root-change sites. Replaces the previous unconditional CoordCache::clear() calls with two targeted methods: invalidate_via_node(node_addr) (drops entries whose cached ancestry contains the changed node, used at parent-switch / become-root / loop-detection sites) and invalidate_other_roots (drops entries from a different tree, used at root-change sites). The previous global flush left find_next_hop returning None for every non-direct-peer destination after every parent switch until the cache passively re-warmed; surgical invalidation preserves entries that remain correct across the topology change. Peer-removal retains the original "no invalidation" behavior (find_next_hop already recomputes against the current peer set every call, and Discovery handles "no route" on demand).
• Rekey integration test (testing/static/scripts/rekey-test.sh): Phase 1, Phase 3, and Phase 5 strict per-pair pings now retry up to 4 attempts (configurable via MAX_PING_ATTEMPTS / PING_RETRY_DELAY). Under low-level packet loss (1% per direction), single-shot 20-pair ping_all misses with probability ~33% per phase from ICMP noise alone, masking the routing-state signal the asserts target. The 4-attempt retry brings that floor to ~3.2e-6 per phase. The wait_for_full_baseline convergence loop itself stays single-shot — retries there would conflate transient ping loss with still-converging routing state. Test scaffold only; no daemon code changes.
• Apply ±15s symmetric jitter per session to the FMP and FSP rekey timer trigger. Eliminates the steady-state dual-initiation race in symmetric-start meshes; previously the smaller-NodeAddr tie-breaker resolved correctness after every cycle's collision. node.rekey.after_secs becomes the nominal interval rather than a floor; mean is preserved.
• Rekey integration test (testing/static/scripts/rekey-test.sh): bumped Phase 1 baseline-convergence headroom from 36s to 60s. Eliminates the intermittent GitHub-runner Phase 1 timeout that previously required gh run rerun --failed. Cost on the success path is unchanged because the wait loop returns as soon as all 20 pairs converge.
• Rekey integration test (testing/static/scripts/rekey-test.sh): added a post-second-rekey settle window in Phase 5, mirroring Phase 3's existing 12-second pattern. Closes the intermittent GitHub-runner Phase 5 per-pair-ping flake caused by post-rekey routing convergence exceeding the per-ping 5-second timeout under runner CPU contention. Cost on the success path is a fixed 12s per suite run.
• ACL-allowlist integration test (testing/acl-allowlist/test.sh): converted assert_log_contains from a one-shot docker logs | grep snapshot into a bounded poll with the same wait-with-timeout shape as wait_for_peers_exact. Absorbs the millisecond-to-second variance in the XX-handshake cross-connection tie-breaker: the inbound-handshake-context rejection can land tens of milliseconds after the test's previous one-shot grep gave up, producing a pre-existing flake on next-branch CI. Success-path cost is unchanged — the helper returns as soon as the pattern appears.
• Nostr-discovered NAT-traversal events (BootstrapEvent::Established and BootstrapEvent::Failed) for peers that are already connected or actively handshaking are now short-circuited at the poll_nostr_discovery dispatch sites before any cooldown bookkeeping or fallback retry scheduling runs. Stale Failed events previously poisoned the per-peer failure-state cooldown of healthy peers and could trigger redundant retraversal attempts via schedule_retry / try_peer_addresses; stale Established handoffs could attempt to adopt a second socket against a live connection. A defense-in-depth guard was added to adopt_established_traversal so the same invariant holds if a future caller bypasses the outer dispatch check. As a side benefit, narrows a cooldown-poisoning vector previously available to an attacker injecting stale failure events for an active peer.

[0.3.0] - 2026-05-11

Added

Mesh Layer (FMP)

• Overlay-discovery and NAT-hole-punching path (opt-in via node.discovery.nostr.enabled). Nodes publish signed overlay adverts as Nostr kind 37195 parameterized replaceable events listing reachable transport endpoints to a configurable set of public relays, and consume peer adverts to populate fallback addresses for via_nostr peers or, under policy: open, for non-configured peers within a budget cap. The kind value is FIPS-specific: 37195 sits in the application-defined replaceable range 30000–39999, and the digits visually spell FIPS (7=F, 1=I, 9=P, 5=S)
• STUN-assisted UDP hole punching for addr: "nat" UDP endpoints. STUN reflexive observation, gift-wrap (NIP-59) offer/answer signaling, and candidate-pair punch planner (LAN-private + reflexive paths attempted in parallel). Successful punches hand the live socket into the standard FIPS UDP transport via a bootstrap-handoff API
• New node.discovery.nostr.* configuration tree with operator-tunable resource caps, replay tracking, and punch timing; new peers[].via_nostr and per-transport advertise_on_nostr / public flags. Cross-field validation at startup catches mis-configured combinations
• Docker NAT lab covering cone, symmetric (TCP-fallback), and LAN scenarios, wired into the integration CI matrix
• One-shot startup advert sweep for Nostr open-discovery. On daemon startup under node.discovery.nostr.policy: open, after a short settle delay (startup_sweep_delay_secs, default 5s) the cached overlay-advert table is iterated once and recent adverts (newer than startup_sweep_max_age_secs, default 3600s) are queued for outbound retry, modulo the same skip-filters as the per-tick sweep (configured peer, already connected, retry-pending, connecting). Closes the gap where peers learned only through relay backlog at startup were not dialed until they republished.
• Diagnostic logging on the open-discovery sweep. Each queued retry now logs at info-level with the peer short-npub and advert age, and a one-line summary (cached count, queued count, per-reason skip counts) is emitted on every startup sweep and on any per-tick sweep that queues at least one retry. Operator-facing visibility into what the auto-dial path is doing.

Platform Support

• Windows platform support: wintun TUN device, TCP control socket on localhost:21210 (in place of the Unix domain socket), Windows Service lifecycle (--install-service, --uninstall-service, --service), ZIP packaging with PowerShell install/uninstall scripts, and CI build/test matrix entry (#45)
• macOS platform support: native utun TUN interface management, raw Ethernet transport via BPF, .pkg packaging with launchd plist and uninstall script, x86_64 cross-compile from arm64, and CI build/unit test jobs
• MIPS atomic ABI support: std::sync::atomic replaced with portable_atomic so 32-bit MIPS targets without native atomics link cleanly (#62, @andrewheadricke).

Mesh Peer Transports

• Bluetooth Low Energy (BLE) L2CAP Connection-Oriented Channel transport (Linux only, requires BlueZ): per-link MTU negotiation, continuous scan/probe peer discovery with cooldown-based deduplication, continuous advertising, deterministic NodeAddr cross-probe tie-breaker, and a configurable connection pool with eviction.
• transports.udp.outbound_only (default false). When true, the UDP transport binds a kernel-assigned ephemeral port (0.0.0.0:0) instead of the configured bind_addr, refuses inbound handshakes, and is never advertised on Nostr regardless of advertise_on_nostr. Use this to participate in the mesh as a pure client — initiate outbound links without exposing an inbound listener on a known port. Implements the long-form fix for udp.bind_addr: "127.0.0.1:..." not actually working as a workaround (Linux pins the loopback source IP, dropping outbound flows to external peers at the routing layer)
• transports.udp.accept_connections (default true). Mirrors the Ethernet/BLE knob; setting to false produces a "client" posture (initiate outbound, refuse inbound msg1 from new addresses). The Node-level handshake gate carves out msg1 from peers already established on this transport so rekey continues to work. Affects every transport via the Transport trait
• Startup validation now rejects transports.udp[*].bind_addr set to a loopback address when at least one peer has a non-loopback UDP address. Replaces the silent "peer link won't establish" failure mode where Linux's source-address routing check dropped outbound flows from the loopback-bound socket. outbound_only: true is exempt from the check (it overrides bind_addr to 0.0.0.0:0)

Security

• Mesh-interface nftables baseline (Linux). Ships /etc/fips/fips.nft as a documented operator conffile and fips-firewall.service (disabled by default) for default-deny inbound on the fips0 mesh interface. Operators enable explicitly with systemctl enable --now fips-firewall.service. Drop-ins in /etc/fips/fips.d/*.nft. See docs/fips-security.md.
• Peer access control list enforcement: optional /etc/fips/peers.allow and /etc/fips/peers.deny files (TCP-Wrappers style) gate outbound connect, inbound msg1, and outbound msg2 against npub, hex pubkey, host alias, or ALL. Files are reloaded automatically on mtime change. New fipsctl acl show query reports the effective rule set (#50, @alexxie16).

LAN Gateway

• New fips-gateway binary that lets unmodified LAN hosts reach FIPS mesh destinations via DNS-allocated virtual IPs and kernel nftables NAT. Virtual-IP pool (fd01::/112 by default) with state-machine lifecycle and TTL-based reclamation; conntrack-backed session tracking; proxy NDP on the LAN interface; control socket at /run/fips/gateway.sock with show_gateway and show_mappings; fipstop Gateway tab with pool gauge and mappings table; design doc at docs/design/fips-gateway.md; integration test harness
• Inbound mesh port forwarding on fips-gateway: new gateway.port_forwards config (list of { listen_port, proto, target } entries, IPv6 targets only) installs prerouting DNAT rules so mesh peers can reach a configured host:port on the gateway's LAN. A LAN-side masquerade is added when any forwards are configured so replies flow back through conntrack.
• Gateway packaging: systemd service unit with After=fips.service, Debian and AUR package entries, OpenWrt procd init with dnsmasq forwarding, proxy NDP, RA route advertisements, and IPv6 forwarding sysctls. Gateway enabled by default on OpenWrt
• fips-gateway DNS upstream probe now retries up to 5 times with a 1-second per-attempt timeout and a 1-second delay between attempts (~10 second worst-case wait), instead of a single 3-second hard-fail. Covers the cold-boot race where the daemon's TUN is up (the systemd ExecStartPre wait gates on that) but the DNS responder is still binding [::1]:5354. Without retry the gateway exited and relied on Restart=on-failure for recovery (5-second blip + spurious error log line per cycle); with retry the gateway recovers gracefully without a unit restart

IPv6 Adapter

• Overhauled .fips DNS handling for systemd-based hosts. The default dns.bind_addr is ::1 (IPv6 loopback) and the setup script picks one of five backends in priority order: a global drop-in at /etc/systemd/resolved.conf.d/fips.conf, the systemd dns-delegate path, resolvectl per-link, standalone dnsmasq, or NetworkManager's dnsmasq plugin. Teardown reverses only what was applied. New testing/dns-resolver/ harness exercises every backend across Debian 12, Debian 13, Ubuntu 22.04, Ubuntu 24.04, and Ubuntu 26.04 (#58, fixes #52, #77).

Operator Tooling

• node.log_level config field (case-insensitive, default info) replaces the hardcoded RUST_LOG=info previously baked into systemd units and the OpenWrt procd init script. The daemon now loads config before initializing tracing so the configured level takes effect; RUST_LOG still overrides when set
• fipsctl show identity-cache lists every cached node identity (npub, IPv6 address, display name, LRU age) alongside the configured cache capacity
• fipsctl show peers extended with per-peer security signals (replay suppression count, consecutive decrypt failures), Noise session counters, session indices, and rekey lifecycle state
• fipsctl show sessions extended with handshake resend count during establishment and rekey/session health fields when established (session start, K-bit epoch, coords warmup remaining, drain state)
• fipsctl show cache now includes individual coordinate cache entries (tree coordinates, depth, path MTU, age). The top-level count field was renamed from entries to count for clarity
• fipsctl show routing expands pending_lookups from a count to per-target detail (attempt, age, last sent), adds pending TUN packet queue depth, and adds per-peer connection retry state (#42, @osh)
• Historical node and per-peer statistics: in-memory time-series rings on the daemon, surfaced through new control-socket queries, fipsctl stats subcommands, and a fipstop Graphs tab with btop-style sparklines (#64).
• fipstop Node tab now carries a "Listening on fips0" panel (right-half of the Traffic block) that lists local IPv6 listening sockets reachable from the mesh interface, paired with the inet fips baseline filter classification for each (proto, port). Rows render in default White (OPEN — the chain has a canonical unrestricted accept rule), DarkGray (filt — chain falls through to counter drop), or DarkGray with a ? State suffix (filt? — the chain references the port but with matchers the panel cannot fully decompose, e.g. saddr filters or jumps). When the fips-firewall.service is not active, the panel renders a yellow banner reminding the operator that all listeners are mesh-exposed. Wildcard binds (local_addr == ::) carry a * suffix in the Process column. Powered by a new show_listening_sockets control query (Linux-only).

Packaging and Deployment

• Arch Linux AUR packaging for fips (release) and fips-git (development) packages with sysusers.d/tmpfiles.d integration (#21, @dskvr)
• packaging/debian/fips-gateway.service now waits up to 30 seconds for the daemon's fips0 TUN to appear before exec'ing the gateway binary (ExecStartPre poll loop). Eliminates the cold-boot race where fips-gateway exits with fips0 interface not found and recovers via Restart=on-failure, producing a 5-second blip and a spurious error log line per restart cycle. If fips0 never appears within 30 seconds, the existing error path runs as before
• packaging/debian/build-deb.sh now auto-derives a per-commit Debian Version field for dev builds (Cargo.toml version ending in -dev) using the form <base>~dev+git<YYYYMMDD>.<sha>[.dirty]-1, e.g. 0.3.0~dev+git20260429.6def31b-1. Each commit produces a uniquely- comparable Version string so apt install ./*.deb and ansible.builtin.apt: deb: no longer silently no-op when one dev build is installed on top of another. The ~dev marker sorts pre-0.3.0 so a tagged release supersedes any prior dev .deb. Tagged release builds (no -dev in Cargo.toml) keep the clean <version>-1 form. Operator override via --version still wins

Examples

• macOS WireGuard sidecar: run FIPS in a local Docker container and route .fips traffic from the macOS host through a WireGuard tunnel to the container's fips0 interface. Only traffic destined for fd00::/8 transits the sidecar; regular internet traffic continues to use the host network (#51)

Documentation

• docs/design/port-advertisement-and-nat-traversal.md documents how nodes find each other through Nostr relays and the STUN-assisted UDP hole punch

Changed

• Noise session ChaCha20-Poly1305 backend switched from RustCrypto's chacha20poly1305 to ring 0.17. ring wraps BoringSSL's hand-tuned ChaCha20-Poly1305 implementation, dispatching to NEON on aarch64 and AVX2 / AVX-512 on x86_64 — typically 3-5 GB/s/core vs the ~600-800 MB/s/core RustCrypto soft path on the same hardware. Wire format unchanged: ChaCha20-Poly1305 is byte-deterministic for a given (key, nonce, plaintext, aad), so any correct AEAD produces identical ciphertext and a mixed pre-swap / post-swap mesh interoperates without protocol awareness. The keyed AEAD is now cached on CipherState instead of being re-derived per packet (the cached Poly1305 key state is the actual perf win); EndToEndState grew from ~600 B to ~1.5 KB as a consequence and is annotated #[allow(clippy::large_enum_variant)] since boxing would re-add a per-packet indirection on every encrypt/decrypt. aarch64 measurements (Apple Silicon docker, two nodes): TCP 1-stream 437 → 1097 Mbps (~2.5×); UDP at 1000 Mbit goes from 599 Mbps / 40 % loss to lossless line-rate; 3-node ping under load 7.68 ms avg / 215 ms max → 0.72 ms / 3.6 ms max as the relay path stops being crypto-bound (#80, @mmalmi)
• Linux UDP receive path uses recvmmsg(2) with a 32-packet batch in place of single-packet recvmsg(2). A single readable() wakeup drains up to 32 datagrams in one syscall before yielding back to the reactor, eliminating the per-packet scheduler-hop + futex cost that previously capped inbound rate at one event per scheduler quantum independent of CPU. SO_RXQ_OVFL is sampled once per batch from the cmsg chain of msgs[0] and surfaced through AsyncUdpSocket::recv_batch so the 1Hz sample_transport_congestion() detector continues to feed the per-transport dropping flag. macOS / Windows fall through to the per-packet path; recvmmsg is Linux-specific (#81, @mmalmi)
• Node::run_rx_loop drains up to 256 additional ready items via try_recv() after each tokio::select! await fires on packet_rx / tun_outbound_rx, in a tight inner loop before yielding. Previously the select cost a full scheduler hop + futex per packet, capping throughput at one event per scheduler quantum with the worker near-idle. biased ordering keeps data-plane branches priority over tick / control / DNS under sustained load; the 256 cap is empirically tuned to keep the worker on a busy stream between yield points (≈ 400 KB of contiguous traffic) while still bounding the inner loop so a flood on one branch can't starve the periodic tick or control socket. Pairs with the UDP recvmmsg change above (#81, @mmalmi)
• PeerIdentity::pubkey_full() now precomputes the parity-aware full public key at construction in from_pubkey. Previously the method fell through to a secp256k1 EC point parse (fe_sqrt + fe_mul + ge_set_xo_var) on every call when the full key wasn't passed at construction (i.e. for every peer constructed from an npub or x-only key) — ~6% of per-packet CPU on the bulk-data send path for a value that never changed after construction. The same EC point parse already runs at construction inside NodeAddr::from_pubkey, so the cost is paid once where it would be paid anyway (#81, @mmalmi)
• Cargo feature flags tui, ble, gateway, and nostr-discovery removed; subsystem inclusion is now driven by platform cfg gates so plain cargo build compiles everything available on the target (#79)
• MMP link-layer report intervals retuned for constrained transports: steady-state floor raised from 100ms to 1000ms, ceiling from 2000ms to 5000ms. Cold-start uses a 200ms floor for the first 5 SRTT samples before switching to steady-state. Reduces BLE overhead ~10× while keeping reports well above the EWMA convergence threshold. Session-layer intervals unchanged
• 35 info-level log messages demoted to debug (handshake cross-connection mechanics, periodic MMP telemetry, TUN/transport shutdown, retry scheduling). Info output now focuses on operator-relevant state changes: lifecycle events, peer promotions, session establishment, parent switches, transport start/stop
• Breaking (control socket JSON): show_cache response field entries has changed type from a u64 count to an array of entry objects; a new count field carries the previous scalar value. show_routing response field pending_lookups has changed type from a u64 count to an array of per-target lookup objects. External consumers parsing these fields as numbers must be updated. In-tree fipstop is adjusted to the new schema. The control socket interface is still pre-1.0 and not covered by stability guarantees
• Discovery rate limiting retuned to be less aggressive at cold start. The previous defaults (30s base post-failure suppression, doubling to a 300s cap, with reset only on parent change / new peer / first RTT / reconnection) reliably outlasted initial mesh convergence: a single timed-out lookup during bloom-filter propagation suppressed any retry for 30s while none of the reset triggers fired on a stable post-handshake topology. The suppression window dictated effective time-to-converge instead of bounding repeat traffic. Replaces the single-lookup-with-internal-retry model (timeout_secs/retry_interval_secs/max_attempts) with a per-attempt timeout sequence in node.discovery.attempt_timeouts_secs (default [1, 2, 4, 8]). Each attempt sends a fresh LookupRequest with a new request_id, which lets successive attempts take different forwarding paths as the bloom and tree state evolve. The destination is declared unreachable only after the full sequence is exhausted (15s total at the default). Disables post-failure suppression by default (backoff_base_secs/backoff_max_secs now both 0); operators with chatty apps generating repeat lookups against unreachable destinations can opt back in
• The docs/ tree is reorganised so readers can find content by what they're trying to do: tutorials for new users, how-to guides for specific tasks, reference material for configuration and protocol details, and design discussion for architectural background. New top-level getting-started.md and per-section landing pages anchor the entry points. Content was reconciled against current source: protocol layer details, wire-format diagrams, configuration knobs, and CLI references were brought back into agreement with the implementation. Gateway feature-set documentation was rewritten end-to-end.
• Test coverage was substantially expanded for the new release surface (discovery state machine, control-socket query handlers, decrypt-failure thresholds, STUN parser, gateway, NAT traversal, packaging install paths) alongside CI-side hardening for the new Windows and macOS platforms.
• Gateway dns.listen source default changed from [::]:53 to [::1]:5353 to match the canonical deployment model (a host already serving DHCP/DNS to a LAN segment, where port 53 is taken by the existing resolver and .fips queries are forwarded to the gateway over loopback). The OpenWrt ipk previously overrode this in its packaged config; the override is now redundant and has been dropped. Operators on a host without a pre-existing resolver on port 53 can opt back into the wildcard bind by setting dns.listen: "[::]:53" explicitly. The new default binds IPv6 loopback only — forwarders that reach the gateway over IPv4 loopback need an explicit IPv4 listen address.
• Generic systemd install tarball brought to feature parity with the .deb and AUR packages. The tarball now ships the fips-gateway binary with its (operator-opt-in) fips-gateway.service, a fips-firewall.service unit with the /etc/fips/fips.nft mesh-interface nftables baseline (also opt-in), an /etc/fips/fips.d/ operator drop-in directory for per-service nft rules, and the multi-backend fips-dns-setup / fips-dns-teardown helpers. install.sh and uninstall.sh handle the new units and conffile (preserve-on-upgrade for fips.nft, like fips.yaml). README.install.md documents the gateway, firewall, and DNS-routing services. Closes the longest-standing parity gap for non-Debian / non-Arch systemd Linux distros (Fedora, RHEL/CentOS, openSUSE, etc.) installing from the release-distribution tarball.

Fixed

• Generic systemd install tarball: install.sh now correctly resolves the fips-dns-setup and fips-dns-teardown helpers from the tarball staging directory. Previously the script referenced them at ${SCRIPT_DIR}/../common/, a path that exists only in the source-repo layout, not in the extracted tarball. Bug latent since the multi-backend DNS helpers landed in 7260ad2; only manifested when operators ran install.sh from an extracted tarball rather than from a source checkout.

• Adopted NAT-traversed UDP transports inherit the primary listener's MTU and buffer config. Node::adopt_established_traversal constructed the adopted UDP transport with UdpConfig::default() (MTU 1280, default recv/send buffer sizes, default accept/advertise flags) regardless of the operator's primary [transports.udp] listener. Operators who set the primary MTU higher (e.g. 1500 on a known-clean LAN path) silently dropped full-sized tunnel datagrams over the NAT-traversed link with no log explaining why throughput collapsed. Lookup now tries transport_name first (so multiple named listeners pick up inheritance from the matching one) and falls back to the unnamed Single listener; bind / external-address fields are cleared since the adopted socket is already bound. The 1280 default was deliberately the IPv6 minimum (the only value guaranteed across arbitrary middlebox paths); with this change, operators who raise the primary MTU accept the tradeoff that NAT-traversed flows initially attempt the higher MTU and may black-hole on tighter paths until reactive MtuExceeded recovery kicks in (#83, @mmalmi)

• TreeAnnounce ancestry on self-root transitions. When a node had no smaller-NodeAddr peer to use as a parent, the spanning-tree state correctly promoted it to root, but the ancestry it advertised on the next TreeAnnounce still referenced its previous parent's path. Receiving peers rejected the announce with invalid ancestry: advertised root X is not the minimum path entry Y, blocking mesh transit on any path that needed to traverse the node. The self-root transition is now detected explicitly in TreeState::become_root and the advertised ancestry rebuilt to start from self. The MMP receive handler surfaces the same path so stale ancestry inherited across reconnect is corrected eagerly rather than waiting for the next observation tick (#82, @mmalmi)

• Auto-connect retry refetches the cached overlay advert unconditionally before each retry attempt, not only when fetch_advert returns zero endpoints (NoTransportForType). The much more common stale-cache failure was: cache returned an endpoint that looked valid (the address learned before the peer's NAT rebound), the dial succeeded at the IP layer, the handshake timed out, MMP fired, the next retry hit the same cached endpoint, looped forever — no NoTransportForType ever fired because the cache had data, just dead data. Refetch now runs unconditionally before each retry attempt (one Filter query against advert_relays with a 2s per-attempt timeout, bounded by the retry backoff cadence). Keeps the retry loop pinned to relay ground truth instead of whatever the cache happened to learn at startup (#82, @mmalmi)

• Stale overlay-advert eviction on NoTransportForType. Mirrors the existing stale-advert sweep that ran from the BootstrapEvent::Failed (NAT-traversal-streak) path, but covers the case where initiate_peer_connection / a retry tick returns NodeError::NoTransportForType — the cache had no addresses for the peer at all. A fire-and-forget refetch_advert_for_stale_check against the peer's npub re-fetches kind 37195 from advert_relays; if the relay has a newer advert it replaces the cached entry, if it has nothing it evicts the entry. Either way the next retry tick goes to fresh data instead of looping on the same dead endpoint. Resolves a deployment regression where a macOS daemon's view of a Linux peer would flap after NAT rebind with no recovery short of a daemon restart (#82, @mmalmi)

• Schedule retry on startup peer-init failure. When initiate_peer_connections() ran at boot, an address-resolution failure (no operational transport for the configured transport types, all addresses unreachable, NAT rebind invalidating cached endpoints) was logged and silently forgotten — the peer entry stayed in a dead state forever, accepting incoming pings but unable to answer them, until the daemon was manually restarted. Now mirrors the BootstrapEvent::Failed path: on a startup peer-init error, parse the peer's npub and call schedule_retry so the peer recovers without operator intervention (#82, @mmalmi)

• Default control-socket path resolution: daemon and client tools now use a shared resolver, eliminating a divergence where fipsctl / fipstop could connect to a socket the daemon never bound (notably on dev runs with XDG_RUNTIME_DIR set, or after a prior packaged install left a root-owned /run/fips behind). Canonical order is /run/fips → $XDG_RUNTIME_DIR/fips/ → /tmp/fips-<name>. The /run/fips arm is selected by directory existence; the kernel enforces actual access at connect(2) time, surfacing a clear EACCES for users not yet in the fips group rather than silently steering them to a path the daemon never bound. XDG_RUNTIME_DIR is validated as an existing directory before being used so stale post-logout values are treated as missing. The deployed fleet is unaffected: packaged configs set node.control.socket_path explicitly.

• UDP transport with advertise_on_nostr: true + public: true + a wildcard bind_addr (e.g. 0.0.0.0:2121) is now advertised with its STUN-discovered public IPv4 instead of being silently dropped from the published Kind 37195 advert. Previously the advert builder filtered the wildcard out (since 0.0.0.0 is not a valid endpoint), but emitted no log explaining what happened — operators saw the daemon up, both flags set, and no UDP endpoint in the advert. The fix runs a one-shot STUN observation against an ephemeral socket on the daemon's configured stun_servers and combines the reflexive IPv4 with the configured listener port for the advert (udp:<eip>:<port>). Successful STUN observations are cached per-transport for one advert_refresh_secs cycle (default 30 min) so we don't re-STUN every refresh. Failed observations are cached for only 60s, so a transient STUN flake at startup retries within ~a minute and grows the advert with UDP as soon as STUN starts working — rather than waiting the full 30-min cycle. Per-server STUN response timeout is 5s for the advert-publish path (vs. 2s for the latency-sensitive per-traversal path), giving slow first-call STUN time to complete without giving up. On STUN failure, the wildcard-bind path still skips, but now logs a loud warn! pointing at the operator-side fixes (set external_addr, bind to a specific IP, or ensure stun_servers reachable). Restores zero-config public-IP autodiscovery on AWS EIP / GCP / Azure setups where binding to the public IP directly is impossible (1:1 NAT)

• New external_addr field on transports.udp.* and transports.tcp.* for explicit advertise-as override. Accepts either a bare IP ("198.51.100.1" — the configured bind_addr port is appended) or a full host:port ("198.51.100.1:8443"). Takes precedence over both the bound address and any STUN-derived autodiscovery. Required for TCP on cloud-NAT setups (AWS EIP, GCP/Azure external IPs) where binding to the public IP directly fails with EADDRNOTAVAIL (the EIP isn't on a host interface). Optional but useful for UDP as a deterministic alternative to STUN — operators who want to skip STUN egress (or whose STUN is blocked) can specify it explicitly. Without external_addr, TCP with a wildcard bind_addr + advertise_on_nostr: true now logs a loud warn! pointing at the two fixes instead of silently skipping

• Nostr-discovery now tolerates ±60s of clock skew on offer/answer freshness checks so a responder whose wall clock leads the initiator's by less than that no longer silently rejects every offer. Previously, a public-test daemon with un-NTP'd peers (or long uptime — now_ms() anchors to SystemTime once at startup, then advances monotonically; post-startup NTP step adjustments don't propagate) would see ~100% signal-timeout rate against skewed peers, indistinguishable from "peer is offline." New optional offerReceivedAt field on the answer payload lets the initiator log per-peer NTP-style skew estimates (DEBUG when ≥30s) for operator visibility. Backward-compatible — older responders that don't fill the field still produce valid answers

• Nostr-discovery NAT-traversal failure suppression: per-npub consecutive-failure counter triggers a 30-min extended cooldown after 5 failures, preventing the daemon from hammering Nostr relays with offers to peers that have gone away. WARN log lines rate-limited to one per peer per 5 min (subsequent failures emit DEBUG with consecutive_failures + remaining cooldown_secs). Threshold-crossing also fires a one-shot active re-check of the peer's Kind 37195 advert against advert_relays; absent → evict cache; newer → refresh + reset streak; same → cooldown stands. New failure_streak_threshold, extended_cooldown_secs, warn_log_interval_secs, failure_state_max_entries config fields under node.discovery.nostr. Per-peer state visible in fipsctl show peers JSON under nostr_traversal

• Tor onion adverts published over Nostr overlay discovery now include the public-facing port (<onion>.onion:<port>) instead of just the bare onion hostname. The publisher previously emitted a bare onion that the parser refused (expected host:port), producing a persistent retry-fail loop on any peer whose Tor advert was the only entry in the discovery cache. New transports.tor.advertised_port config field (default 443, matching the Tor HiddenServicePort convention) controls the advertised port; operators with non-default virtual ports can override.

• TCP-over-FIPS reliability on mesh paths with mixed transport MTUs (e.g. a UDP-1280 hop in the picker set) improved. Three interlocking changes: Node::transport_mtu() is now deterministic across restarts (min across operational transports rather than insertion-order-dependent); the TCP MSS clamp at the TUN boundary reads per-destination path MTU instead of a single global ceiling; and reactive MtuExceeded from forwarders is mirrored back into the TUN-side path_mtu_lookup so later flows pick up forward-path bottlenecks without re-discovery. Windows TUN reader receives the same per-destination plumbing.

• Proactive end-to-end PathMtuNotification now mirrors into the TUN-side path_mtu_lookup (TCP MSS clamp store), parallel to the reactive MtuExceeded mirror that already existed. Previously the proactive handler only updated the session-canonical MmpSessionState.path_mtu; on stable long-lived paths where the destination's echo had tightened the session MTU but no transit router had emitted a fresh MtuExceeded (because all current traffic was already sized by the tighter session value), new TCP flows opened in that window kept getting clamped by the staler discovery-time value. The proactive mirror closes that gap with the same tighter-only semantics — never loosens the clamp.

• Nostr-discovered peers running an FMP-protocol version we cannot speak no longer trigger an indefinite retraversal storm. Open- discovery NAT-traversal succeeds at the UDP layer regardless of protocol version, so the daemon would adopt the punched socket, drop every incoming packet at Unknown FMP version, idle out after 31s, and re-fire the full STUN-offer-answer-punch sequence ~30s later — every minute, forever, against peers the handshake literally cannot complete with. The rx loop now detects mismatched- version packets arriving on adopted bootstrap transports, reverse- maps to the originating npub, and applies a long structural cooldown to the discovery layer's failure_state so the next open-discovery sweep skips the peer until either side upgrades. One-shot WARN per fresh observation; subsequent mismatches inside the cooldown window are silent. New protocol_mismatch_cooldown_secs config field under node.discovery.nostr (default 86400 = 24h), separate from the transient-failure extended_cooldown_secs.

• fipstop now uses ratatui::try_init() instead of ratatui::init(), so terminal initialization failures (e.g. Docker on macOS Sequoia, or environments without a usable tty) produce a clean error message instead of a hard crash

• Spanning-tree updates that change only the internal path between root and leaf — without changing the root or the depth — now propagate to leaves correctly. Previously a leaf could continue routing against a stale internal path until the parent or depth also changed.

[0.2.1] - 2026-05-11

Added

• Linux release artifact workflow: builds x86_64 and aarch64 tarballs and .deb packages on v* tag push, with SHA-256 checksums
• AUR publish workflow for tagged stable releases

Changed

• Validate bloom filter fill ratio on FilterAnnounce ingress. Inbound FilterAnnounce messages whose derived false-positive rate exceeds node.bloom.max_inbound_fpr (new config field, default 0.05) are rejected silently on the wire, logged at WARN, and counted in a new bloom.fill_exceeded counter. A rate-limited WARN also fires if our own outgoing filter's FPR exceeds the cap. BloomFilter::estimated_count now takes max_fpr and returns Option<f64>, returning None for saturated filters; this propagates through compute_mesh_size into estimated_mesh_size (already Option<u64>)

Fixed

• Control socket path detection in fipsctl and fipstop now checks for the /run/fips/ directory instead of the socket file inside it, so users not yet in the fips group get a clear "Permission denied" error instead of a misleading "No such file" fallback to $XDG_RUNTIME_DIR (#30, reported by @Sebastix)
• OpenWrt ipk build excluded BLE feature that requires D-Bus, which is unavailable on OpenWrt targets
• IPv6 routing policy rule added at TUN setup to protect fd00::/8 from interception by Tailscale's table 52 default route
• Bloom filter routing no longer swallows traffic when no bloom candidate is strictly closer than the current node. find_next_hop now falls through to greedy tree routing in that case instead of returning NoRoute, which previously caused dropped packets in topologies where the tree parent was closer but not a bloom candidate
• Auto-connect peers now reconnect after a graceful Disconnect notification from the remote side. handle_disconnect previously removed the peer without scheduling a reconnect, orphaning the entry on a clean upstream shutdown; the other removal paths (link-dead, decrypt failure, peer restart) already scheduled reconnect (#60, reported by @SwapMarket)
• fipsctl connect now rejects FIPS mesh (fd00::/8) addresses for udp, tcp, and ethernet transports with a clear error message instead of echoing success while the daemon silently failed the bind with EAFNOSUPPORT (#61, reported by @SwapMarket)
• Tighten TreeAnnounce ancestry validation to match the spanning tree specification. The receive path now verifies that the ancestry is structurally consistent with the signed parent declaration before mutating tree state.
• Make the tree ancestry acceptance unit test deterministic. test_tree_announce_validate_semantics_accepts_valid_non_root generated a random signing identity while pinning the fixed root to node_addr[0] = 0x01; about 2 in 256 random identities were numerically smaller than the claimed root, triggering AncestryRootNotMinimum. The test now regenerates the identity until its node_addr is strictly larger than both the fixed parent and root.

[0.2.0] - 2026-03-22

Added

Operator Tooling

• fipsctl connect and disconnect commands for runtime peer management via control socket, with hostname resolution from /etc/fips/hosts

IPv6 Adapter

• Pre-seed identity cache from configured peer npubs at startup, so TUN packets can be dispatched immediately without waiting for handshake completion (@v0l)

Mesh Peer Transports

• New Tor transport with SOCKS5 and directory-mode onion service for anonymous inbound and outbound peering
• DNS hostname support in peer addresses for UDP and TCP transports
• Non-blocking transport connect for connection-oriented transports (TCP, Tor)

Packaging and Deployment

• Reproducible build infrastructure: Rust toolchain pinning via rust-toolchain.toml, SOURCE_DATE_EPOCH in CI and packaging scripts, deterministic archive timestamps
• Top-level packaging Makefile for unified build across formats
• Kubernetes sidecar deployment example with Nostr relay demo
• Nostr release publishing in OpenWrt package workflow
• SHA-256 hash output in CI build and OpenWrt workflows

Testing and CI

• Maelstrom chaos scenario with dynamic topology mutation and ephemeral node identities via connect/disconnect commands
• Consolidated Docker test harness infrastructure

Changed

• Discovery protocol: replace flooding with bloom-filter-guided tree routing. Includes originator retry (T=0/T=5s/T=10s), exponential backoff after timeouts and bloom misses, and transit-side per-target rate limiting. Removed 257-byte visited bloom filter from LookupRequest wire format. This is a breaking change; nodes running versions prior to this release will not be compatible.

Fixed

• DNS responder returned NXDOMAIN for A queries on valid .fips names, causing resolvers to give up without trying AAAA. Now returns NOERROR with empty answers for non-AAAA queries on resolvable names. (#9, reported by @alopatindev)
• Stale end-to-end session left in session table after peer removal blocked session re-establishment on reconnect — remove_active_peer now cleans up self.sessions and self.pending_tun_packets. (#5, @v0l)
• schedule_reconnect reset exponential backoff to zero on each link-dead cycle instead of preserving accumulated retry count. (#5, @v0l)
• FMP/FSP rekey dual-initiation race on high-latency links (Tor): both sides' timers fired simultaneously, both msg1s crossed in flight, each side's responder path destroyed the initiator state. Fixed with deterministic tie-breaker (smaller NodeAddr wins as initiator).
• Parent selection SRTT gate bypass: evaluate_parent used default cost 1.0 for peers filtered out by has_srtt(), defeating the MMP eligibility gate. Now skips unmeasured candidates when any peer has cost data.
• FSP rekey cutover race: initiator cut over before responder received msg3, causing AEAD failures. Fixed by deferring initiator cutover by 2 seconds.
• MMP metric discontinuity after rekey: receiver state carried stale counters across rekey, inflating reorder counts and jitter. Fixed via reset_for_rekey().
• Auto-connect peers exhausted max_retries on initial connection failures and were permanently abandoned. Now retry indefinitely with exponential backoff capped at 300 seconds.
• Control socket permissions: non-root users couldn't connect. Daemon now chowns socket and directory to root:fips group at bind time.
• Post-rekey jitter spikes: old-session frames arriving via the drain window produced 2,000–7,000ms jitter spikes that corrupted the EWMA estimator. Added a 15-second grace period after rekey cutover that suppresses jitter updates until drain-window frames have flushed. (#10)
• ICMPv6 Packet Too Big source was set to the local FIPS address, which Linux ignores (loopback PTB check). Now uses the original packet's destination so the kernel honors the PMTU update. (#16, @v0l)
• Reverse delivery ratio used lifetime cumulative counters instead of per-interval deltas, making ETX unresponsive to recent loss. (#14)
• MMP delta guards used prev_rr > 0 to detect first report, conflating it with a legitimate zero counter. Replaced with has_prev_rr. (#14)

[0.1.0] - 2026-03-12

Added (Initial Release)

Session Layer (FSP)

• End-to-end encrypted datagram service between mesh nodes addressed by Nostr npub
• Noise XK sessions with mutual authentication, replay protection, and forward secrecy
• Automatic session rekeying with configurable time/message thresholds and drain window for in-flight packets
• Port multiplexing for multiple services over a single session
• Session-layer metrics: sender/receiver reports with RTT, jitter, delivery ratio, and burst loss tracking
• Passive RTT measurement via spin bit

IPv6 Adapter

• IPv6 adapter interface allowing tunneling TCP/IPv6 through FIPS mesh for traditional IP applications (TUN interface)
• DNS resolver allowing IP applications to reach nodes by npub.fips name
• Host-to-npub static mappings: resolve hostname.fips via host map populated from peer config aliases and /etc/fips/hosts file

Mesh Layer (FMP)

• Self-organized core mesh routing protocol with adaptive least cost forwarding
• Noise IK hop-by-hop link encryption with mutual authentication and replay protection between peer nodes
• Distributed spanning tree construction with cost-based parent selection and adaptive reconfiguration
• Destination route discovery via bloom filter-based directed search protocol
• Path MTU discovery with per-link MTU tracking and MtuExceeded error signaling
• Link-layer MMP: SRTT, jitter, one-way delay trends, packet loss, and ETX metrics
• Link-layer heartbeat with configurable liveness timeout for dead peer detection
• Epoch-based peer restart detection
• Automatic link rekeying with K-bit epoch coordination and drain window
• Static peer auto-reconnect with exponential backoff
• Multi-address peers with transport priority-based failover
• Msg1 rate limiting for handshake DoS protection

Mesh Peer Transports

• UDP overlay transport with inbound and static outbound peer configuration
• TCP overlay transport with listening port and static outbound peer support
• Ethernet/WiFi transport (MAC address based, no IP stack) with optional automatic peer discovery and auto-connect

Operator Tooling

• Ephemeral or persistent node identity with key file management
• Unix domain control socket for runtime observability
• fipsctl CLI tool for control socket interaction and node management
• Comprehensive node and transport statistics via control socket
• fipstop TUI monitoring tool with real-time session, peer, and transport configuration and metrics display

Packaging and Deployment

• Debian/Ubuntu .deb packaging via cargo-deb
• Systemd service packaging with tarball installer
• OpenWRT package with opkg feed and init script
• Docker sidecar deployment for containerized services
• Build version metadata: git commit hash, dirty flag, and target triple embedded in all binaries via --version

Testing and CI

• Comprehensive unit and integration tests covering all protocol layers and transports
• Docker test harness with static and stochastic topologies
• Chaos testing with simulated severe network conditions: latency, packet loss, reordering, and peer churn
• CI with GitHub Actions: x86_64 and aarch64, integration test matrix, nextest JUnit reporting
• Local CI runner script (testing/ci-local.sh)

Project

• Design documentation suite covering all protocol layers
• CHANGELOG.md following Keep a Changelog format
• Repository mirrored to ngit