Five findings from the latest review on #758 (2 medium, 3 nit):
Medium:
- browser_oauth_routes.oauth_login_callback + oauth_routes.oauth_callback_nextcloud:
fail closed with 400 when the oauth_session row is unknown/expired. Previously
both callbacks fell through with code_verifier="" and expected_nonce=None,
silently bypassing the PKCE + nonce protections introduced in earlier rounds.
Symmetric unit tests pin both contracts.
- token_utils.verify_id_token: use secrets.compare_digest for the nonce check
instead of short-circuit !=. Mirrors the sibling PKCE verifier comparison;
closes the last secret-equality timing-side-channel surface in the auth path.
Nit:
- Tighten the comment at all 4 mcp_authorization_code/code_verifier store +
retrieve sites so a future refactor sees the field reuse immediately
(renaming the column requires a schema migration).
- _should_use_secure_cookies: explicit string normalisation instead of
bool(settings.cookie_secure). Dynaconf normally coerces but tests / direct
settings.set calls can leave the raw string in place — bool("false") is True.
New parametrized unit tests cover the coercion matrix + http/https fallback.
- oauth_routes.py:591 f-string log converted to lazy %s formatting (folded into
the Flow 2 callback rewrite).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Seven findings from the latest review on #758, plus a regression test
catching the substance of the cache-stampede fix:
- verify_id_token: widen id_token annotation to str | None to match
callers passing nc_token_response.get("id_token")
- extract_user_id_from_token: use JSON-RPC reserved error code -32001
instead of -1
- _get_cached: per-URL anyio.Lock dict + meta-lock coalesces concurrent
cache misses into a single IdP fetch (mirrors token_broker.py idiom)
- delete_browser_session: collapse SELECT+DELETE into atomic
DELETE ... RETURNING user_id (SQLite >= 3.35)
- new test_origin_normalise.py: parametrized port/scheme/host equivalence
cases for the CSRF Origin guard
- browser_oauth_routes: correct misleading "PR #758 finding 5" cross-
references (finding 5 was Fernet-key hardening, not CSRF)
- ASProxySession.nonce: make required, drop spurious "legacy session"
default; reword the in-flight `or None` comment to reflect that
ASProxySession is purely in-memory
- new test_get_cached_coalesces_concurrent_misses: pins the
cache-stampede protection — fires 10 concurrent _get_cached calls and
asserts exactly one HTTP fetch
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- oauth_login_callback's integrated-mode token-exchange branch now reuses
the shared discovery cache via get_oidc_discovery (round-2 finding 1).
- AS proxy flow now generates an OIDC nonce in oauth_authorize, stores it
on ASProxySession, forwards it to the IdP, and passes it as
expected_nonce to verify_id_token in _oauth_callback_as_proxy
(round-2 finding 2).
- Consolidate the two parallel discovery caches: oauth_routes' local
_discovery_cache and _get_cached_discovery are removed; all callers
now go through token_utils.get_oidc_discovery, which acquires the
follow_redirects=True knob it needs for Nextcloud installs without
pretty URLs (round-2 finding 3).
- Demote per-user INFO logs in oauth_tools.py (check_logged_in,
get_provisioning_status) to DEBUG; the elicitation auth URL is no
longer logged because it contains a sensitive state token
(round-2 finding 4).
Also pin nonce binding behaviour with a new unit test that asserts
_oauth_callback_as_proxy forwards session.nonce to verify_id_token, and
update test mocks to track the cache consolidation.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Blocking:
- AS proxy callback now calls verify_id_token before caching the proxy
code so a tampered IdP response can't smuggle identity claims.
Important:
- Browser OAuth flow generates and verifies an OIDC nonce; new alembic
migration 006 adds the nonce column to oauth_sessions.
- _origin_matches_self logs a warning when CSRF check is bypassed.
- oauth_tools.py uses get_shared_storage instead of fresh handles.
Nits:
- New token_utils.get_oidc_discovery shares the 5-minute cache with
verify_id_token; oauth_login (integrated) and _revoke_refresh_token_at_idp
now use it instead of issuing fresh discovery fetches.
- Drop typing.Optional from oauth_tools.py in favour of X | None.
CI:
- test.yml generates an ephemeral Fernet TOKEN_ENCRYPTION_KEY per run
with openssl, removing the dependency on a missing repo secret.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Addresses the two remaining 🟡 findings from the PR #758 follow-up review:
1. extract_user_id_from_token previously fell back to "default_user" when
the verified access token had no sub claim. In a multi-tenant deployment
a malformed IdP token could have bucketed every request under a single
sentinel user, risking cross-tenant data exposure. The function now
raises McpError on that branch; the BasicAuth no-token sentinel path is
preserved.
2. oauth_callback_nextcloud (Flow 2) read the PKCE code_verifier from
oauth_sessions but never deleted the row, leaving the verifier valid for
the full 10-minute TTL. The row is now deleted eagerly inside the same
branch, mirroring oauth_login_callback in browser_oauth_routes.
Also wires TOKEN_ENCRYPTION_KEY through the docker-compose step in the CI
test workflow so the integration matrix can boot — every job had been
failing fast on the ${TOKEN_ENCRYPTION_KEY:?...} interpolation guard added
in PR #758 finding 5.
Tests pin both fixes (test_token_utils_user_id.py,
test_oauth_callback_session_cleanup.py).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
