`POST /renew` is authenticated by mTLS with the very leaf it renews, so once
that leaf lapsed the host could never renew it and the tunnel stayed down until
an operator re-paired by hand. Production hit exactly this: the Mac slept
through its 8h renewal window, the 24h leaf expired, and the agent then logged
`client certificate has expired; renew before dialling` 6380 times over 8 days
without recovering.
Three layers independently refused an expired leaf, so all three had to move:
- agent `buildTlsOptions` gains an opt-in `expiredGraceMs`. Absent/0 keeps the
historical fail-closed behaviour, and the TUNNEL dial never passes it — only
the renew transport does. Past the window it throws the new
`CertExpiredBeyondGraceError`.
- agent rotator routes an already-expired leaf to a separate recovery endpoint
and treats "beyond grace" as TERMINAL: report once via `onExhausted`, stop
retrying, and name the fix (re-pair) instead of spamming warnings forever.
- control-plane `assertPresentedCertTrusted` grants a bounded grace on
`notAfter` only. Chain validation, SPIFFE identity, `notBefore`, and the
registry `active`/account checks are all unchanged, so revocation still bites.
- new `deploy/nginx/recover-mtls.conf` (:8472). The strict enroll vhost cannot
host this: under `ssl_verify_client optional` nginx answers a bare 400 as soon
as a presented cert fails verification, so an expired leaf never reaches the
location — and the directive is server-level, not per-location.
Grace defaults to 30 days on both ends and is configurable (`RECOVER_URL`,
`expiredRenewGraceMs`). The honest trade is recorded in the code: a stale stolen
leaf stays reusable for the window, which widens an existing exposure (an
unexpired stolen leaf already renews indefinitely) rather than opening a new one.
Verified: agent 296/296, control-plane 286/286, tsc clean on both.
Multi-tenant reverse-tunnel service ("ngrok for Claude Code" with E2E): a
host-agent dials OUT to an operator-run relay; external devices reach the host
THROUGH the relay, routed by per-tenant subdomain, forwarding ciphertext only
(the relay never sees plaintext). Lets a customer reach their own self-hosted
web-terminal from anywhere with zero networking setup.
Packages — all tsc-strict + vitest green (656 tests), cross-package integration verified:
- relay-contracts: frozen shared contracts (mux frame codec, data model,
capability token, E2E envelope, pairing) — the src/types.ts analog
- term-relay: native WS mux + stateless data plane (subdomain routing, ciphertext forward)
- agent: host-agent (pairing, per-host Ed25519 + mTLS dial-out, forwards to 127.0.0.1:3000)
- control-plane: accounts/hosts registry, pairing-code flow, routing table, provisioning
- relay-e2e: browser<->agent E2E (X25519 ECDH through relay, AEAD, anti-replay, recoverable replay key)
- relay-auth: Passkey/WebAuthn, capability tokens, per-host certs, deny-by-default tenant isolation
- relay-web: browser login + Web Crypto E2E + client-side preview rendering
Security invariants INV1-15 enforced; cross-tenant isolation CI tripwire live
(.github/workflows/relay-tripwire.yml). Design + implementation-level plans in
docs/PLAN_RELAY_*.md and docs/EXPLORE_RELAY_SERVICE.md.
NOTE: generated autonomously per the reviewed plans. The security-critical
packages (relay-e2e, relay-auth) REQUIRE expert security audit before any real
deployment — passing tests prove self-consistency, not resistance to attackers.
Base app (src/, public/) unchanged; concurrent desktop work left uncommitted.
