Files
n_signer/src/key_store.c

1667 lines
56 KiB
C

#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_PQ_SIG, /* post-quantum signatures (ML-DSA, SLH-DSA) */
PURPOSE_PQ_KEM, /* post-quantum key encapsulation (ML-KEM) */
PURPOSE_UNKNOWN
} role_purpose_t;
/* Curve enum */
typedef enum {
CURVE_SECP256K1 = 0,
CURVE_ED25519,
CURVE_X25519,
CURVE_ML_DSA_65,
CURVE_SLH_DSA_128S,
CURVE_ML_KEM_768,
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 */
#define ENFORCE_ERR_ALGORITHM -4 /* algorithm not valid for verb */
/* New algorithm-based verb defines (algorithm is a parameter, not implicit) */
#define VERB_SIGN "sign"
#define VERB_VERIFY "verify"
#define VERB_ENCAPSULATE "encapsulate"
#define VERB_DECAPSULATE "decapsulate"
#define VERB_DERIVE_SHARED "derive_shared_secret"
/* 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"
#define VERB_MINE_EVENT "mine_event"
#define VERB_SIGN_DATA "sign_data"
#define VERB_VERIFY_SIG "verify_signature"
#define VERB_SSH_SIGN "ssh_sign"
#define VERB_KEM_ENCAPS "kem_encapsulate"
#define VERB_KEM_DECAPS "kem_decapsulate"
/*
* Check whether `verb` is allowed to execute against `role`.
* Returns ENFORCE_OK if allowed, or an ENFORCE_ERR_* code.
*/
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 160
#define POLICY_MAX_ALGS 16
/* 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;
/* Algorithm-based (new) */
char algorithms[16][32]; /* algorithm names; POLICY_MAX_ALGS */
int alg_count;
int index_min; /* -1 = any */
int index_max; /* -1 = any */
/* Common */
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);
/* Check whether caller_id is allowed to invoke `verb` with the given
* algorithm and index (algorithm-based policy). Returns POLICY_ALLOW,
* POLICY_DENY, POLICY_PROMPT, or POLICY_NO_MATCH. */
int policy_check_algorithm(const policy_table_t *table, const char *caller_id,
const char *verb, const char *algorithm, int index,
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 pq_crypto.h */
/* Algorithm identifiers */
typedef enum {
CRYPTO_ALG_SECP256K1 = 0, /* existing, Nostr */
CRYPTO_ALG_ED25519, /* new, SSH signatures */
CRYPTO_ALG_X25519, /* new, key agreement */
CRYPTO_ALG_ML_DSA_65, /* new, PQ signatures */
CRYPTO_ALG_SLH_DSA_128S, /* new, PQ signatures */
CRYPTO_ALG_ML_KEM_768, /* new, PQ KEM */
CRYPTO_ALG_UNKNOWN
} crypto_alg_t;
/* Key sizes for each algorithm (compile-time constants) */
typedef struct {
size_t priv_key_len;
size_t pub_key_len;
size_t sig_len; /* 0 for KEM */
size_t ciphertext_len; /* 0 for signatures */
size_t shared_secret_len; /* 0 for signatures */
} crypto_alg_sizes_t;
/* Get size info for an algorithm. Returns NULL for CRYPTO_ALG_UNKNOWN. */
const crypto_alg_sizes_t *crypto_alg_get_sizes(crypto_alg_t alg);
/* Map role_curve_t + role_purpose_t to crypto_alg_t.
* Returns CRYPTO_ALG_UNKNOWN for unsupported combinations. */
crypto_alg_t crypto_alg_from_role(role_curve_t curve, role_purpose_t purpose);
/* Convert crypto_alg_t to string. Returns NULL for unknown. */
const char *crypto_alg_to_str(crypto_alg_t alg);
/* Parse string to crypto_alg_t. Returns CRYPTO_ALG_UNKNOWN for unrecognized. */
crypto_alg_t crypto_alg_from_str(const char *s);
/* ed25519: derive keypair from a 32-byte seed.
* priv_out and pub_out must be at least 32 bytes each.
* Returns 0 on success, -1 on error. */
int crypto_ed25519_keygen_from_seed(const unsigned char *seed, size_t seed_len,
unsigned char *priv_out, unsigned char *pub_out);
/* ed25519: sign a message. priv is 32-byte private key.
* sig_out must be at least 64 bytes. Returns 0 on success, -1 on error. */
int crypto_ed25519_sign(const unsigned char *priv, size_t priv_len,
const unsigned char *msg, size_t msg_len,
unsigned char *sig_out, size_t *sig_out_len);
/* ed25519: verify a signature. pub is 32-byte public key.
* Returns 0 on valid, 1 on invalid, -1 on error. */
int crypto_ed25519_verify(const unsigned char *pub, size_t pub_len,
const unsigned char *msg, size_t msg_len,
const unsigned char *sig, size_t sig_len);
/* x25519: derive keypair from a 32-byte seed.
* priv_out and pub_out must be at least 32 bytes each.
* Returns 0 on success, -1 on error. */
int crypto_x25519_keygen_from_seed(const unsigned char *seed, size_t seed_len,
unsigned char *priv_out, unsigned char *pub_out);
/* x25519: derive shared secret from our private key and peer's public key.
* shared_out must be at least 32 bytes. Returns 0 on success, -1 on error. */
int crypto_x25519_ecdh(const unsigned char *our_priv, size_t priv_len,
const unsigned char *peer_pub, size_t pub_len,
unsigned char *shared_out, size_t *shared_out_len);
/* Derive a 32-byte seed from a mnemonic using a BIP-44 path (SLIP-0010).
* seed_out must be at least 32 bytes. Returns 0 on success, -1 on error. */
int crypto_derive_seed_from_mnemonic(const char *mnemonic, const char *path,
unsigned char *seed_out, size_t seed_out_len);
/* ML-DSA-65: generate keypair from a 32-byte seed (deterministic).
* priv_out must be at least 4032 bytes, pub_out at least 1952 bytes.
* Returns 0 on success, -1 on error. */
int crypto_ml_dsa_65_keygen_from_seed(const unsigned char *seed, size_t seed_len,
unsigned char *priv_out, unsigned char *pub_out);
/* ML-DSA-65: sign a message. priv is 4032-byte private key.
* sig_out must be at least 3309 bytes. Returns 0 on success, -1 on error. */
int crypto_ml_dsa_65_sign(const unsigned char *priv, size_t priv_len,
const unsigned char *msg, size_t msg_len,
unsigned char *sig_out, size_t *sig_out_len);
/* ML-DSA-65: verify a signature. pub is 1952-byte public key.
* Returns 0 on valid, 1 on invalid, -1 on error. */
int crypto_ml_dsa_65_verify(const unsigned char *pub, size_t pub_len,
const unsigned char *msg, size_t msg_len,
const unsigned char *sig, size_t sig_len);
/* SLH-DSA-128s: generate keypair from a 32-byte seed (deterministic).
* priv_out must be at least 64 bytes, pub_out at least 32 bytes.
* Returns 0 on success, -1 on error. */
int crypto_slh_dsa_128s_keygen_from_seed(const unsigned char *seed, size_t seed_len,
unsigned char *priv_out, unsigned char *pub_out);
/* SLH-DSA-128s: sign a message. priv is 64-byte private key.
* sig_out must be at least 7856 bytes. Returns 0 on success, -1 on error. */
int crypto_slh_dsa_128s_sign(const unsigned char *priv, size_t priv_len,
const unsigned char *msg, size_t msg_len,
unsigned char *sig_out, size_t *sig_out_len);
/* SLH-DSA-128s: verify a signature. pub is 32-byte public key.
* Returns 0 on valid, 1 on invalid, -1 on error. */
int crypto_slh_dsa_128s_verify(const unsigned char *pub, size_t pub_len,
const unsigned char *msg, size_t msg_len,
const unsigned char *sig, size_t sig_len);
/* ML-KEM-768: generate keypair from a 32-byte seed (deterministic).
* priv_out must be at least 2400 bytes, pub_out at least 1184 bytes.
* Returns 0 on success, -1 on error. */
int crypto_ml_kem_768_keygen_from_seed(const unsigned char *seed, size_t seed_len,
unsigned char *priv_out, unsigned char *pub_out);
/* ML-KEM-768: encapsulate. pub is 1184-byte public key.
* ct_out must be at least 1088 bytes, ss_out at least 32 bytes.
* Returns 0 on success, -1 on error. */
int crypto_ml_kem_768_encaps(const unsigned char *pub, size_t pub_len,
unsigned char *ct_out, unsigned char *ss_out);
/* ML-KEM-768: decapsulate. priv is 2400-byte secret key, ct is 1088-byte ciphertext.
* ss_out must be at least 32 bytes. Returns 0 on success, -1 on error. */
int crypto_ml_kem_768_decaps(const unsigned char *priv, size_t priv_len,
const unsigned char *ct, size_t ct_len,
unsigned char *ss_out);
/* Deterministic PRNG for PQ keygen (replaces PQClean randombytes()). */
void pq_drbg_init(const unsigned char *seed, size_t seed_len);
int pq_drbg_randombytes(unsigned char *buf, size_t len);
void pq_drbg_zeroize(void);
/* from alg_api.h */
/* Check whether a verb is valid for an algorithm (algorithm-based enforcement).
* Returns ENFORCE_OK, ENFORCE_ERR_ALGORITHM, or ENFORCE_ERR_UNKNOWN_VERB.
* Does NOT check purpose — purpose is irrelevant for the new verbs. */
int enforce_verb_algorithm(const char *verb, crypto_alg_t alg);
/* secp256k1 Schnorr (BIP-340) sign arbitrary bytes.
* priv is 32-byte scalar, pub is 32-byte x-only pubkey, sig_out is 64 bytes.
* Hashes the message with SHA-256 before signing (like Nostr event signing).
* Returns 0 on success, -1 on error. */
int crypto_secp256k1_schnorr_sign(const unsigned char *priv, size_t priv_len,
const unsigned char *msg, size_t msg_len,
unsigned char *sig_out, size_t *sig_out_len);
/* secp256k1 Schnorr (BIP-340) verify.
* pub is 32-byte x-only pubkey, sig is 64 bytes.
* Returns 0 on valid, 1 on invalid, -1 on error. */
int crypto_secp256k1_schnorr_verify(const unsigned char *pub, size_t pub_len,
const unsigned char *msg, size_t msg_len,
const unsigned char *sig, size_t sig_len);
/* secp256k1 ECDSA sign arbitrary bytes.
* priv is 32-byte scalar, sig_out must be at least 64 bytes (compact DER r||s).
* Hashes the message with SHA-256 before signing.
* Returns 0 on success, -1 on error. */
int crypto_secp256k1_ecdsa_sign(const unsigned char *priv, size_t priv_len,
const unsigned char *msg, size_t msg_len,
unsigned char *sig_out, size_t *sig_out_len);
/* secp256k1 ECDSA verify.
* pub is 32-byte x-only pubkey (converted internally to compressed form).
* sig is 64-byte compact (r||s). Returns 0 on valid, 1 on invalid, -1 on error. */
int crypto_secp256k1_ecdsa_verify(const unsigned char *pub, size_t pub_len,
const unsigned char *msg, size_t msg_len,
const unsigned char *sig, size_t sig_len);
/* ---- Algorithm key cache ----
* On-demand key derivation by algorithm+index, separate from the role-based
* key_store. Holds up to ALG_KEY_CACHE_MAX derived keys in secure memory.
* When full, the oldest entry is evicted (FIFO). */
#define ALG_KEY_CACHE_MAX 32
typedef struct {
crypto_alg_t alg;
int index;
secure_buf_t private_key;
secure_buf_t public_key;
char pubkey_hex[8192];
char key_id[17];
int valid;
} alg_key_entry_t;
typedef struct {
alg_key_entry_t entries[ALG_KEY_CACHE_MAX];
int count;
} algorithm_key_cache_t;
/* Initialize an empty cache. */
void alg_key_cache_init(algorithm_key_cache_t *cache);
/* Zeroize and free all entries. Idempotent. */
void alg_key_cache_wipe(algorithm_key_cache_t *cache);
/* Look up a cached entry by (alg, index). Returns NULL if not present. */
const alg_key_entry_t *alg_key_cache_get(algorithm_key_cache_t *cache, crypto_alg_t alg, int index);
/* Derive a key on-demand by (alg, index) and store it in the cache.
* Uses the standard derivation path for the algorithm.
* Returns 0 on success, -1 on error. */
int alg_key_cache_derive(algorithm_key_cache_t *cache, const mnemonic_state_t *mnemonic, crypto_alg_t alg, int index);
/* from crypto.h */
/* Per-role derived key material (stored in secure memory) */
typedef struct {
secure_buf_t private_key; /* mlock'd, variable size per algorithm */
secure_buf_t public_key; /* mlock'd, variable size per algorithm */
char pubkey_hex[8192]; /* hex-encoded public key (PQ pubkeys are large) */
char npub[128]; /* bech32 npub (secp256k1 only, empty for others) */
crypto_alg_t alg; /* which algorithm this key was derived for */
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.
* 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);
/* Mine a Nostr event with NIP-13 proof-of-work, then sign it.
* event_json is the unsigned event JSON string.
* difficulty: target leading zero bits (0 = no target, mine for full timeout)
* threads: number of mining threads (1..32)
* timeout_sec: time budget in seconds (0 = use 600s safety default)
* Returns a newly-allocated JSON string containing a result object:
* {"event":"<signed event json>","achieved_difficulty":N,"target_difficulty":N,
* "target_reached":bool,"elapsed_sec":N,"attempts":N}
* Returns NULL on error. Caller must free() the returned string. */
char *crypto_mine_event(const key_store_t *store, int role_index,
const char *event_json, int difficulty,
int threads, int timeout_sec);
/* 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;
algorithm_key_cache_t *alg_key_cache; /* algorithm-based on-demand keys */
} 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, algorithm_key_cache_t *alg_key_cache);
/*
* 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.
*/
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[POLICY_CALLER_MAX_LEN]; /* "uid:<n>" */
} caller_identity_t;
/* Server context */
typedef struct {
char socket_name[SERVER_SOCKET_NAME_MAX];
char last_error[256];
int listen_fd;
int running;
dispatcher_ctx_t *dispatcher;
policy_table_t *policy;
int socket_name_explicit;
} server_ctx_t;
void server_init(server_ctx_t *ctx, const char *socket_name, int socket_name_explicit,
dispatcher_ctx_t *dispatcher, policy_table_t *policy);
int server_start(server_ctx_t *ctx);
const char *server_last_error(const server_ctx_t *ctx);
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);
void server_stop(server_ctx_t *ctx);
int server_get_caller(int fd, caller_identity_t *out);
/* from socket_name.h */
int socket_name_random(char *out, size_t out_len);
/* from main.h */
#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/nip013.h>
#include <nostr_core/nip019.h>
#include <nostr_core/nip044.h>
#include <nostr_core/utils.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#define NSIGNER_ENCRYPT_OUTPUT_MAX 65536
/*
* Derive a secp256k1 (Nostr) key for a role into the variable-length
* derived_key_t. Returns 0 on success, -1 on failure.
*/
static int derive_secp256k1(derived_key_t *dst, const role_entry_t *role,
const mnemonic_state_t *mnemonic) {
unsigned char priv[32];
unsigned char pub[32];
const crypto_alg_sizes_t *sz;
sz = crypto_alg_get_sizes(CRYPTO_ALG_SECP256K1);
if (sz == NULL) {
return -1;
}
if (secure_buf_alloc(&dst->private_key, sz->priv_key_len) != 0) {
return -1;
}
if (secure_buf_alloc(&dst->public_key, sz->pub_key_len) != 0) {
secure_buf_free(&dst->private_key);
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);
secure_buf_free(&dst->public_key);
return -1;
}
memcpy(dst->private_key.data, priv, sz->priv_key_len);
memcpy(dst->public_key.data, pub, sz->pub_key_len);
nostr_bytes_to_hex((const unsigned char *)dst->public_key.data,
sz->pub_key_len, dst->pubkey_hex);
dst->npub[0] = '\0';
(void)nostr_key_to_bech32(pub, "npub", dst->npub);
dst->alg = CRYPTO_ALG_SECP256K1;
dst->valid = 1;
secure_memzero(priv, sizeof(priv));
secure_memzero(pub, sizeof(pub));
return 0;
}
/*
* Derive an ed25519 key for a role using SLIP-0010 derivation from the
* mnemonic. The path is m/44'/102001'/<n>'/0'/0' (all hardened).
* Returns 0 on success, -1 on failure.
*/
static int derive_ed25519(derived_key_t *dst, const role_entry_t *role,
const mnemonic_state_t *mnemonic) {
unsigned char seed[32];
unsigned char priv[32];
unsigned char pub[32];
const crypto_alg_sizes_t *sz;
char path[ROLE_PATH_MAX];
sz = crypto_alg_get_sizes(CRYPTO_ALG_ED25519);
if (sz == NULL) {
return -1;
}
if (secure_buf_alloc(&dst->private_key, sz->priv_key_len) != 0) {
return -1;
}
if (secure_buf_alloc(&dst->public_key, sz->pub_key_len) != 0) {
secure_buf_free(&dst->private_key);
return -1;
}
snprintf(path, sizeof(path), "m/44'/102001'/%d'/0'/0'", role->nostr_index);
if (crypto_derive_seed_from_mnemonic(mnemonic_get_phrase(mnemonic), path,
seed, sizeof(seed)) != 0) {
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
if (crypto_ed25519_keygen_from_seed(seed, sizeof(seed), priv, pub) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
memcpy(dst->private_key.data, priv, sz->priv_key_len);
memcpy(dst->public_key.data, pub, sz->pub_key_len);
nostr_bytes_to_hex((const unsigned char *)dst->public_key.data,
sz->pub_key_len, dst->pubkey_hex);
dst->npub[0] = '\0';
dst->alg = CRYPTO_ALG_ED25519;
dst->valid = 1;
secure_memzero(seed, sizeof(seed));
secure_memzero(priv, sizeof(priv));
secure_memzero(pub, sizeof(pub));
return 0;
}
/*
* Derive an x25519 key for a role using SLIP-0010 derivation from the
* mnemonic. The path is m/44'/102002'/<n>'/0'/0' (all hardened).
* Returns 0 on success, -1 on failure.
*/
static int derive_x25519(derived_key_t *dst, const role_entry_t *role,
const mnemonic_state_t *mnemonic) {
unsigned char seed[32];
unsigned char priv[32];
unsigned char pub[32];
const crypto_alg_sizes_t *sz;
char path[ROLE_PATH_MAX];
sz = crypto_alg_get_sizes(CRYPTO_ALG_X25519);
if (sz == NULL) {
return -1;
}
if (secure_buf_alloc(&dst->private_key, sz->priv_key_len) != 0) {
return -1;
}
if (secure_buf_alloc(&dst->public_key, sz->pub_key_len) != 0) {
secure_buf_free(&dst->private_key);
return -1;
}
snprintf(path, sizeof(path), "m/44'/102002'/%d'/0'/0'", role->nostr_index);
if (crypto_derive_seed_from_mnemonic(mnemonic_get_phrase(mnemonic), path,
seed, sizeof(seed)) != 0) {
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
if (crypto_x25519_keygen_from_seed(seed, sizeof(seed), priv, pub) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
memcpy(dst->private_key.data, priv, sz->priv_key_len);
memcpy(dst->public_key.data, pub, sz->pub_key_len);
nostr_bytes_to_hex((const unsigned char *)dst->public_key.data,
sz->pub_key_len, dst->pubkey_hex);
dst->npub[0] = '\0';
dst->alg = CRYPTO_ALG_X25519;
dst->valid = 1;
secure_memzero(seed, sizeof(seed));
secure_memzero(priv, sizeof(priv));
secure_memzero(pub, sizeof(pub));
return 0;
}
/*
* Derive an ML-DSA-65 key for a role using SLIP-0010 derivation from the
* mnemonic. The path is m/44'/102003'/<n>'/0'/0' (all hardened).
* Returns 0 on success, -1 on failure.
*/
static int derive_ml_dsa_65(derived_key_t *dst, const role_entry_t *role,
const mnemonic_state_t *mnemonic) {
unsigned char seed[32];
const crypto_alg_sizes_t *sz;
char path[ROLE_PATH_MAX];
sz = crypto_alg_get_sizes(CRYPTO_ALG_ML_DSA_65);
if (sz == NULL) {
return -1;
}
if (secure_buf_alloc(&dst->private_key, sz->priv_key_len) != 0) {
return -1;
}
if (secure_buf_alloc(&dst->public_key, sz->pub_key_len) != 0) {
secure_buf_free(&dst->private_key);
return -1;
}
snprintf(path, sizeof(path), "m/44'/102003'/%d'/0'/0'", role->nostr_index);
if (crypto_derive_seed_from_mnemonic(mnemonic_get_phrase(mnemonic), path,
seed, sizeof(seed)) != 0) {
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
if (crypto_ml_dsa_65_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)dst->private_key.data,
(unsigned char *)dst->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
nostr_bytes_to_hex((const unsigned char *)dst->public_key.data,
sz->pub_key_len, dst->pubkey_hex);
dst->npub[0] = '\0';
dst->alg = CRYPTO_ALG_ML_DSA_65;
dst->valid = 1;
secure_memzero(seed, sizeof(seed));
return 0;
}
/*
* Derive an SLH-DSA-128s key for a role using SLIP-0010 derivation from the
* mnemonic. The path is m/44'/102004'/<n>'/0'/0' (all hardened).
* Returns 0 on success, -1 on failure.
*/
static int derive_slh_dsa_128s(derived_key_t *dst, const role_entry_t *role,
const mnemonic_state_t *mnemonic) {
unsigned char seed[32];
const crypto_alg_sizes_t *sz;
char path[ROLE_PATH_MAX];
sz = crypto_alg_get_sizes(CRYPTO_ALG_SLH_DSA_128S);
if (sz == NULL) {
return -1;
}
if (secure_buf_alloc(&dst->private_key, sz->priv_key_len) != 0) {
return -1;
}
if (secure_buf_alloc(&dst->public_key, sz->pub_key_len) != 0) {
secure_buf_free(&dst->private_key);
return -1;
}
snprintf(path, sizeof(path), "m/44'/102004'/%d'/0'/0'", role->nostr_index);
if (crypto_derive_seed_from_mnemonic(mnemonic_get_phrase(mnemonic), path,
seed, sizeof(seed)) != 0) {
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
if (crypto_slh_dsa_128s_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)dst->private_key.data,
(unsigned char *)dst->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
nostr_bytes_to_hex((const unsigned char *)dst->public_key.data,
sz->pub_key_len, dst->pubkey_hex);
dst->npub[0] = '\0';
dst->alg = CRYPTO_ALG_SLH_DSA_128S;
dst->valid = 1;
secure_memzero(seed, sizeof(seed));
return 0;
}
/*
* Derive an ML-KEM-768 key for a role using SLIP-0010 derivation from the
* mnemonic. The path is m/44'/102005'/<n>'/0'/0' (all hardened).
* Returns 0 on success, -1 on failure.
*/
static int derive_ml_kem_768(derived_key_t *dst, const role_entry_t *role,
const mnemonic_state_t *mnemonic) {
unsigned char seed[32];
const crypto_alg_sizes_t *sz;
char path[ROLE_PATH_MAX];
sz = crypto_alg_get_sizes(CRYPTO_ALG_ML_KEM_768);
if (sz == NULL) {
return -1;
}
if (secure_buf_alloc(&dst->private_key, sz->priv_key_len) != 0) {
return -1;
}
if (secure_buf_alloc(&dst->public_key, sz->pub_key_len) != 0) {
secure_buf_free(&dst->private_key);
return -1;
}
snprintf(path, sizeof(path), "m/44'/102005'/%d'/0'/0'", role->nostr_index);
if (crypto_derive_seed_from_mnemonic(mnemonic_get_phrase(mnemonic), path,
seed, sizeof(seed)) != 0) {
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
if (crypto_ml_kem_768_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)dst->private_key.data,
(unsigned char *)dst->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&dst->private_key);
secure_buf_free(&dst->public_key);
return -1;
}
nostr_bytes_to_hex((const unsigned char *)dst->public_key.data,
sz->pub_key_len, dst->pubkey_hex);
dst->npub[0] = '\0';
dst->alg = CRYPTO_ALG_ML_KEM_768;
dst->valid = 1;
secure_memzero(seed, sizeof(seed));
return 0;
}
/*
* Derive a key for a single role into `dst` using the algorithm selected
* by crypto_alg_from_role(). Returns 0 on success, -1 if the algorithm
* is unsupported/unknown or derivation fails.
*/
static int derive_for_role(derived_key_t *dst, const role_entry_t *role,
const mnemonic_state_t *mnemonic) {
crypto_alg_t alg;
alg = crypto_alg_from_role(role->curve, role->purpose);
if (alg == CRYPTO_ALG_UNKNOWN) {
return -1;
}
switch (alg) {
case CRYPTO_ALG_SECP256K1:
return derive_secp256k1(dst, role, mnemonic);
case CRYPTO_ALG_ED25519:
return derive_ed25519(dst, role, mnemonic);
case CRYPTO_ALG_X25519:
return derive_x25519(dst, role, mnemonic);
case CRYPTO_ALG_ML_DSA_65:
return derive_ml_dsa_65(dst, role, mnemonic);
case CRYPTO_ALG_SLH_DSA_128S:
return derive_slh_dsa_128s(dst, role, mnemonic);
case CRYPTO_ALG_ML_KEM_768:
return derive_ml_kem_768(dst, role, mnemonic);
case CRYPTO_ALG_UNKNOWN:
default:
return -1;
}
}
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];
derived_key_t *dst = &store->keys[i];
role->derived = 0;
role->pubkey_hex[0] = '\0';
if (role->selector_type != SELECTOR_NOSTR_INDEX) {
continue;
}
if (derive_for_role(dst, role, mnemonic) != 0) {
continue;
}
strncpy(role->pubkey_hex, dst->pubkey_hex, sizeof(role->pubkey_hex) - 1);
role->pubkey_hex[sizeof(role->pubkey_hex) - 1] = '\0';
role->derived = 1;
derived_count++;
}
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;
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_buf_free(&dst->public_key);
secure_memzero(dst->pubkey_hex, sizeof(dst->pubkey_hex));
secure_memzero(dst->npub, sizeof(dst->npub));
dst->alg = CRYPTO_ALG_UNKNOWN;
dst->valid = 0;
if (role->selector_type != SELECTOR_NOSTR_INDEX) {
return -1;
}
if (derive_for_role(dst, role, mnemonic) != 0) {
return -1;
}
strncpy(role->pubkey_hex, dst->pubkey_hex, sizeof(role->pubkey_hex) - 1);
role->pubkey_hex[sizeof(role->pubkey_hex) - 1] = '\0';
role->derived = 1;
if (store->count < table->count) {
store->count = table->count;
}
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;
}
/* ---- mine_result_t and miner_run are defined in miner.c ---- */
typedef struct {
cJSON *best_event;
int achieved_difficulty;
int target_difficulty;
int target_reached;
int elapsed_sec;
uint64_t total_attempts;
} mine_result_t;
int miner_run(cJSON *event, const unsigned char *private_key,
int target_difficulty, int thread_count, int timeout_sec,
mine_result_t *result);
char *crypto_mine_event(const key_store_t *store, int role_index,
const char *event_json, int difficulty,
int threads, int timeout_sec) {
const unsigned char *private_key;
cJSON *parsed = NULL;
mine_result_t result;
char *event_str = NULL;
cJSON *result_obj = 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;
}
memset(&result, 0, sizeof(result));
if (miner_run(parsed, private_key, difficulty, threads, timeout_sec, &result) != 0) {
cJSON_Delete(parsed);
return NULL;
}
if (result.best_event == NULL) {
cJSON_Delete(parsed);
return NULL;
}
event_str = cJSON_PrintUnformatted(result.best_event);
cJSON_Delete(result.best_event);
cJSON_Delete(parsed);
if (event_str == NULL) {
return NULL;
}
result_obj = cJSON_CreateObject();
if (result_obj == NULL) {
free(event_str);
return NULL;
}
cJSON_AddItemToObject(result_obj, "event", cJSON_CreateString(event_str));
free(event_str);
cJSON_AddNumberToObject(result_obj, "achieved_difficulty", result.achieved_difficulty);
cJSON_AddNumberToObject(result_obj, "target_difficulty", result.target_difficulty);
cJSON_AddBoolToObject(result_obj, "target_reached", result.target_reached);
cJSON_AddNumberToObject(result_obj, "elapsed_sec", result.elapsed_sec);
cJSON_AddNumberToObject(result_obj, "attempts", (double)result.total_attempts);
out = cJSON_PrintUnformatted(result_obj);
cJSON_Delete(result_obj);
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_buf_free(&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].alg = CRYPTO_ALG_UNKNOWN;
store->keys[i].valid = 0;
}
store->count = 0;
}
/* ===========================================================================
* Algorithm key cache — on-demand key derivation by (algorithm, index).
* ========================================================================== */
static int alg_key_derive_entry(alg_key_entry_t *entry,
const mnemonic_state_t *mnemonic,
crypto_alg_t alg, int index) {
unsigned char seed[32];
const crypto_alg_sizes_t *sz;
char path[ROLE_PATH_MAX];
int path_cointype;
if (entry == NULL || mnemonic == NULL) {
return -1;
}
sz = crypto_alg_get_sizes(alg);
if (sz == NULL) {
return -1;
}
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
secure_memzero(entry->pubkey_hex, sizeof(entry->pubkey_hex));
secure_memzero(entry->key_id, sizeof(entry->key_id));
entry->valid = 0;
entry->alg = CRYPTO_ALG_UNKNOWN;
entry->index = 0;
if (secure_buf_alloc(&entry->private_key, sz->priv_key_len) != 0) {
return -1;
}
if (secure_buf_alloc(&entry->public_key, sz->pub_key_len) != 0) {
secure_buf_free(&entry->private_key);
return -1;
}
if (alg == CRYPTO_ALG_SECP256K1) {
if (nostr_derive_keys_from_mnemonic(mnemonic_get_phrase(mnemonic),
index,
(unsigned char *)entry->private_key.data,
(unsigned char *)entry->public_key.data) != 0) {
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
} else {
switch (alg) {
case CRYPTO_ALG_ED25519: path_cointype = 102001; break;
case CRYPTO_ALG_X25519: path_cointype = 102002; break;
case CRYPTO_ALG_ML_DSA_65: path_cointype = 102003; break;
case CRYPTO_ALG_SLH_DSA_128S: path_cointype = 102004; break;
case CRYPTO_ALG_ML_KEM_768: path_cointype = 102005; break;
default:
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
snprintf(path, sizeof(path), "m/44'/%d'/%d'/0'/0'", path_cointype, index);
if (crypto_derive_seed_from_mnemonic(mnemonic_get_phrase(mnemonic), path,
seed, sizeof(seed)) != 0) {
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
switch (alg) {
case CRYPTO_ALG_ED25519:
if (crypto_ed25519_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)entry->private_key.data,
(unsigned char *)entry->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
break;
case CRYPTO_ALG_X25519:
if (crypto_x25519_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)entry->private_key.data,
(unsigned char *)entry->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
break;
case CRYPTO_ALG_ML_DSA_65:
if (crypto_ml_dsa_65_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)entry->private_key.data,
(unsigned char *)entry->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
break;
case CRYPTO_ALG_SLH_DSA_128S:
if (crypto_slh_dsa_128s_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)entry->private_key.data,
(unsigned char *)entry->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
break;
case CRYPTO_ALG_ML_KEM_768:
if (crypto_ml_kem_768_keygen_from_seed(seed, sizeof(seed),
(unsigned char *)entry->private_key.data,
(unsigned char *)entry->public_key.data) != 0) {
secure_memzero(seed, sizeof(seed));
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
break;
default:
secure_memzero(seed, sizeof(seed));
secure_buf_free(&entry->private_key);
secure_buf_free(&entry->public_key);
return -1;
}
secure_memzero(seed, sizeof(seed));
}
nostr_bytes_to_hex((const unsigned char *)entry->public_key.data,
sz->pub_key_len, entry->pubkey_hex);
if (strlen(entry->pubkey_hex) >= 16) {
memcpy(entry->key_id, entry->pubkey_hex, 16);
entry->key_id[16] = '\0';
} else {
entry->key_id[0] = '\0';
}
entry->alg = alg;
entry->index = index;
entry->valid = 1;
return 0;
}
void alg_key_cache_init(algorithm_key_cache_t *cache) {
if (cache == NULL) {
return;
}
memset(cache, 0, sizeof(*cache));
}
void alg_key_cache_wipe(algorithm_key_cache_t *cache) {
int i;
if (cache == NULL) {
return;
}
for (i = 0; i < ALG_KEY_CACHE_MAX; ++i) {
secure_buf_free(&cache->entries[i].private_key);
secure_buf_free(&cache->entries[i].public_key);
secure_memzero(cache->entries[i].pubkey_hex, sizeof(cache->entries[i].pubkey_hex));
secure_memzero(cache->entries[i].key_id, sizeof(cache->entries[i].key_id));
cache->entries[i].alg = CRYPTO_ALG_UNKNOWN;
cache->entries[i].index = 0;
cache->entries[i].valid = 0;
}
cache->count = 0;
}
const alg_key_entry_t *alg_key_cache_get(algorithm_key_cache_t *cache, crypto_alg_t alg, int index) {
int i;
if (cache == NULL) {
return NULL;
}
for (i = 0; i < cache->count && i < ALG_KEY_CACHE_MAX; ++i) {
if (cache->entries[i].valid &&
cache->entries[i].alg == alg &&
cache->entries[i].index == index) {
return &cache->entries[i];
}
}
return NULL;
}
int alg_key_cache_derive(algorithm_key_cache_t *cache, const mnemonic_state_t *mnemonic, crypto_alg_t alg, int index) {
int slot;
if (cache == NULL || mnemonic == NULL) {
return -1;
}
if (!mnemonic_is_loaded(mnemonic)) {
return -1;
}
if (alg_key_cache_get(cache, alg, index) != NULL) {
return 0;
}
if (cache->count >= ALG_KEY_CACHE_MAX) {
secure_buf_free(&cache->entries[0].private_key);
secure_buf_free(&cache->entries[0].public_key);
secure_memzero(&cache->entries[0], sizeof(cache->entries[0]));
memmove(&cache->entries[0], &cache->entries[1],
(ALG_KEY_CACHE_MAX - 1) * sizeof(alg_key_entry_t));
memset(&cache->entries[ALG_KEY_CACHE_MAX - 1], 0, sizeof(alg_key_entry_t));
slot = ALG_KEY_CACHE_MAX - 1;
cache->count = ALG_KEY_CACHE_MAX;
} else {
slot = cache->count;
cache->count++;
}
if (alg_key_derive_entry(&cache->entries[slot], mnemonic, alg, index) != 0) {
cache->count = slot;
memset(&cache->entries[slot], 0, sizeof(cache->entries[slot]));
return -1;
}
return 0;
}