feat(auth): Add CSRF debug logging for login flow#107153
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Add debug logging to help diagnose CSRF token mismatches affecting staff/superusers on POST /auth/2fa/. Changes: - Log CSRF cookie hash and session key hash on all /auth/* requests - Enhanced csrf_failure logging with cookie hash, POST token hash, origin, user-agent, and path This allows comparing token hashes between form render (GET) and submit (POST) to verify the multi-tab cookie overwrite hypothesis. Only first 8 chars of SHA256 hashes are logged to avoid leaking sensitive token values.
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## Summary Add debug logging to help diagnose CSRF token mismatches affecting staff/superusers on `POST /auth/2fa/` with reason "CSRF token from POST incorrect". ## Changes **`src/sentry/web/frontend/base.py`** - Added `csrf.auth_request` logging in `dispatch()` for all `/auth/*` paths - Logs: `path`, `method`, `csrf_cookie_hash`, `session_key_hash`, `user_id` **`src/sentry/web/frontend/csrf_failure.py`** - Enhanced `csrf_failure` logging with: - `csrf_cookie_hash` and `csrf_post_token_hash` (for comparison) - `path`, `origin`, `user_agent` - Preserved existing fields (`reason`, `referer`, `user_id`, etc.) ## How to Debug When a CSRF failure occurs, compare the logs: 1. **`csrf.auth_request`** (on GET /auth/2fa/) - Shows `csrf_cookie_hash` at form render time 2. **`csrf.auth_request`** (on POST /auth/2fa/) - Shows `csrf_cookie_hash` at submit time 3. **`csrf_failure`** - Shows both `csrf_cookie_hash` and `csrf_post_token_hash` | Scenario | Indicates | |----------|-----------| | `csrf_cookie_hash` differs between GET and POST | Cookie was overwritten (multi-tab hypothesis) | | Hashes match but `csrf_post_token_hash` differs from `csrf_cookie_hash` | Stale form token | ## Security Only first 8 chars of SHA256 hashes are logged to avoid leaking sensitive token values. ## Test Plan - [x] Ran `pytest tests/sentry/web/frontend/test_twofactor.py` - 6 passed - [x] Ran `pytest tests/sentry/web/frontend/test_auth_login.py` - 45 passed - [x] Pre-commit hooks pass
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Summary
Add debug logging to help diagnose CSRF token mismatches affecting staff/superusers on
POST /auth/2fa/with reason "CSRF token from POST incorrect".Changes
src/sentry/web/frontend/base.pycsrf.auth_requestlogging indispatch()for all/auth/*pathspath,method,csrf_cookie_hash,session_key_hash,user_idsrc/sentry/web/frontend/csrf_failure.pycsrf_failurelogging with:csrf_cookie_hashandcsrf_post_token_hash(for comparison)path,origin,user_agentreason,referer,user_id, etc.)How to Debug
When a CSRF failure occurs, compare the logs:
csrf.auth_request(on GET /auth/2fa/) - Showscsrf_cookie_hashat form render timecsrf.auth_request(on POST /auth/2fa/) - Showscsrf_cookie_hashat submit timecsrf_failure- Shows bothcsrf_cookie_hashandcsrf_post_token_hashcsrf_cookie_hashdiffers between GET and POSTcsrf_post_token_hashdiffers fromcsrf_cookie_hashSecurity
Only first 8 chars of SHA256 hashes are logged to avoid leaking sensitive token values.
Test Plan
pytest tests/sentry/web/frontend/test_twofactor.py- 6 passedpytest tests/sentry/web/frontend/test_auth_login.py- 45 passed