Function main_build_identity

src/main.c:1202–1258

}

static main_build_identity_status_t main_build_identity(cbm_daemon_build_identity_t *identity) {
    if (!identity) {
        return MAIN_BUILD_IDENTITY_INVALID_OUTPUT;
    }
    if (!cbm_index_supervisor_capture_build_fingerprint()) {
        return MAIN_BUILD_IDENTITY_PROCESS_FINGERPRINT;
    }
    const char *fingerprint = cbm_index_supervisor_build_fingerprint();
    if (!fingerprint) {
        return MAIN_BUILD_IDENTITY_PROCESS_FINGERPRINT;
    }
    const char *cache = cbm_resolve_cache_dir();
    char canonical_cache[MAIN_PATH_CAP];
    static char cache_fingerprint[CBM_SHA256_HEX_LEN + 1];
    if (!cache || !cache[0]) {
        return MAIN_BUILD_IDENTITY_CACHE_RESOLVE;
    }
    /* Preserve one intentional alias spelling at the process boundary: an
     * existing directory (including a symlink supplied by the user) is
     * resolved first. Only a genuinely absent root goes through mkdir_p's
     * component-by-component no-follow creation path. The process then uses
     * only the resulting canonical path, so retargeting the original alias
     * cannot move storage after cohort admission. */
    bool cache_ready = cbm_canonical_path(cache, canonical_cache, sizeof(canonical_cache));
    if (!cache_ready && cbm_mkdir_p(cache, 0700)) {
        cache_ready = cbm_canonical_path(cache, canonical_cache, sizeof(canonical_cache));
    }
    if (!cache_ready || !cbm_is_dir(canonical_cache)) {
        return MAIN_BUILD_IDENTITY_CACHE_CANONICALIZE;
    }
    cbm_normalize_path_sep(canonical_cache);
    /* Admission is account-scoped, so its storage authority must be too.
     * Harden the canonical object before hashing it. Replacement of this
     * owner-only path by the same already-compromised OS account is outside
     * the v1 threat boundary; cross-account and unsafe filesystem states fail
     * here before any daemon/cohort state is opened. */
    if (!cbm_daemon_ipc_private_directory_secure(canonical_cache)) {
        return MAIN_BUILD_IDENTITY_CACHE_PRIVATE;
    }
    /* Every cache consumer in this process must use the exact path whose
     * fingerprint joins the account-wide cohort. Keeping an original symlink
     * spelling in the environment would let a later retarget move storage
     * while the process still advertises the old canonical root. */
    if (cbm_setenv("CBM_CACHE_DIR", canonical_cache, 1) != 0) {
        return MAIN_BUILD_IDENTITY_CACHE_ENVIRONMENT;
    }
    cbm_sha256_hex(canonical_cache, strlen(canonical_cache), cache_fingerprint);
    *identity = (cbm_daemon_build_identity_t){
        .semantic_version = CBM_VERSION,
        .build_fingerprint = fingerprint,
        .cache_fingerprint = cache_fingerprint,
        .protocol_abi = CBM_DAEMON_RUNTIME_WIRE_ABI,
        .store_abi = 1,
        .feature_abi = 1,
    };
    return MAIN_BUILD_IDENTITY_OK;
}