CLI Machine-ID Token

Overview

OmniRoute CLI commands authenticate against the local management API using a HMAC-SHA256(machine-id, salt) token sent via the x-omniroute-cli-token request header.

This allows CLI subcommands (omniroute status, omniroute providers, etc.) to call management endpoints without requiring the user to supply a JWT or password on every invocation.

How it works

1. getMachineTokenSync() reads the hardware machine ID via node-machine-id (falls back to an empty string on failure, disabling CLI auth).
2. It computes HMAC-SHA256(machine_id, salt) and returns the full 64-char hex digest — a deterministic, non-reversible token tied to this machine.
3. The CLI sends the token as x-omniroute-cli-token only when the resolved destination is an explicit loopback URL (localhost, 127.0.0.0/8, or loopback IPv6). Requests carrying the token use redirect: error, so a local redirect cannot forward it to another origin. Remote contexts use scoped access tokens instead. If derivation is unavailable, the CLI omits the header and omniroute doctor reports the failure instead of treating an empty token as valid.
4. The server (src/server/authz/policies/management.ts) recomputes the expected token with the same salt and compares via timingSafeEqual to prevent timing-based extraction.

Security properties

Property	Detail
Loopback-only	Accepted only when the server’s trusted peer-locality stamp (derived from the real TCP peer address) says loopback. The client-controlled Host header is never trusted for locality.
Constant-time compare	crypto.timingSafeEqual prevents timing attacks.
Non-reversible	HMAC output cannot recover the machine-id.
No always-protected bypass	isAlwaysProtectedPath() is evaluated before the CLI token check. /api/shutdown and /api/settings/database always require JWT.
Non-exportable	Token is never written to disk or logged.

Default salt (random per install)

When OMNIROUTE_CLI_SALT is not set, the salt is a random 64-char hex string generated once and persisted at <DATA_DIR>/cli-token-salt.json (mode 0600) — not the checked-in literal omniroute-cli-auth-v1. Both getActiveSalt() in src/lib/machineToken.ts and its mirror in bin/cli/utils/cliToken.mjs read the same file, so the server and every CLI invocation on this install converge on the same value; the checked-in literal is used only as a last-resort fallback when no persisted or env salt can be established yet (for example a fresh CLI-only install before the server has ever run). This closes a weakness of the old fixed literal default: /etc/machine-id is commonly world-readable, so any local user could otherwise derive the same token for every install that never set OMNIROUTE_CLI_SALT.

Salt rotation

Set OMNIROUTE_CLI_SALT to rotate the derived token without code changes — it always takes priority over the persisted per-install salt. After rotation, all CLI processes on this machine will use the new token automatically. Useful after a process-list leak that may have exposed the previous derived value.

# Persistent rotation (add to shell profile)
export OMNIROUTE_CLI_SALT="my-secret-salt-2026"

# Verify new token is in use
omniroute status

Legacy format (SHA-256, 32-char) — still accepted

Before the HMAC format above, the CLI derived its token as SHA-256(machineId + salt).hex[0..32] (a 32-char prefix) in bin/cli/utils/cliToken.mjs (getLegacyCliTokenSync in src/lib/machineToken.ts).

For backwards compatibility the server accepts both formats: the verifier builds expectedTokens = [getMachineTokenSync(), getLegacyCliTokenSync()] and compares the incoming header against each with timingSafeEqual (src/server/authz/policies/management.ts and src/lib/middleware/cliTokenAuth.ts). So a token is valid if it matches either the 64-char HMAC digest or the 32-char legacy SHA-256 prefix.

Opt-out: set OMNIROUTE_DISABLE_CLI_TOKEN=true (env or .env) to disable the CLI token mechanism entirely; all access then requires an explicit API key. On multi-user hosts this is recommended, since machine-id is per-device (not per-user) and another user on the same host could compute the same token.

Files

File	Purpose
src/lib/machineToken.ts	Token derivation (getMachineTokenSync)
bin/cli/utils/cliToken.mjs	CLI-side mirror of the same derivation
<DATA_DIR>/cli-token-salt.json	Persisted random per-install salt
src/server/authz/headers.ts	CLI_TOKEN_HEADER constant
src/server/authz/policies/management.ts	Server-side verification
src/server/authz/routeGuard.ts	Loopback host check (isLoopbackHost)

See also

• docs/security/ROUTE_GUARD_TIERS.md — route protection tiers
• docs/architecture/AUTHZ_GUIDE.md — full authorization pipeline

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OmniRoute source repository (a58000c7685f)