Chris Coutinho
e331544cee
feat: Implement RFC 8693 token exchange for Keycloak (ADR-002 Tier 2)
...
Implements OAuth 2.0 Token Exchange (RFC 8693) enabling the MCP server to
exchange service account tokens for user-scoped tokens. This provides an
alternative to refresh tokens for background operations.
**Core Implementation:**
- Added `get_service_account_token()` method to KeycloakOAuthClient for
client_credentials grant
- Added `exchange_token_for_user()` method implementing RFC 8693 token exchange
- Fixed Fernet encryption key handling in RefreshTokenStorage (was incorrectly
base64 decoding already-encoded keys)
- Updated OAuth configuration to support offline_access scope and refresh token
storage infrastructure
**Keycloak Configuration:**
- Enabled `serviceAccountsEnabled` in realm-export.json
- Added `token.exchange.grant.enabled` attribute
- Added `client.token.exchange.standard.enabled` attribute (required for
Keycloak 26.2+ Standard Token Exchange V2)
- Fresh Keycloak imports now correctly enable token exchange
**Docker Compose:**
- Added TOKEN_ENCRYPTION_KEY and ENABLE_OFFLINE_ACCESS environment variables
- Created oauth-tokens volume for refresh token storage
- Configured both mcp-oauth and mcp-keycloak services
**Testing & Documentation:**
- Added tests/manual/test_token_exchange.py - Validates complete RFC 8693 flow
- Added tests/manual/test_nextcloud_impersonate.py - Documents session-based
impersonation limitations
- Added docs/oauth-impersonation-findings.md - Comprehensive investigation
findings and resolution documentation
**Verified Working:**
✅ Service account token acquisition (client_credentials grant)
✅ RFC 8693 token exchange for internal-to-internal tokens
✅ Exchanged tokens validate with Nextcloud APIs
✅ Keycloak 26.4.2 Standard Token Exchange V2 support
**Known Limitations:**
- User impersonation (requested_subject) requires Keycloak Legacy V1 with
preview features
- Cross-client token exchange limited to same realm
- Refresh token storage infrastructure ready but unused (MCP protocol limitation)
Dependencies: aiosqlite>=0.20.0
🤖 Generated with [Claude Code](https://claude.com/claude-code )
Co-Authored-By: Claude <noreply@anthropic.com >
2025-11-02 22:03:19 +01:00
Chris Coutinho
f34366a260
feat: Add Keycloak OAuth provider support with refresh token storage
...
Implements Keycloak as an external OIDC provider following ADR-002
architecture for background job authentication using offline_access.
## Features
- Keycloak OAuth provider with PKCE and offline_access support
- Refresh token storage with Fernet encryption
- Token verifier for both JWT and opaque tokens
- Multi-client validation (realm-level trust)
- Sample configuration for Keycloak integration
## Implementation
### OAuth Provider (keycloak_oauth.py)
- Authorization Code Flow with PKCE
- Refresh token exchange
- OIDC discovery endpoint support
- Token validation with JWKS
### Token Storage (refresh_token_storage.py)
- Encrypted storage using Fernet symmetric encryption
- SQLite backend for persistence
- Token rotation support
- Per-user token management
### Token Verifier Updates
- Support both JWT (self-encoded) and opaque tokens
- JWKS-based JWT signature verification
- Introspection endpoint fallback for opaque tokens
- Scope extraction from both token types
### Configuration
- .env.keycloak.sample: Example configuration with Keycloak URLs
- docs/keycloak-multi-client-validation.md: Realm-level validation documentation
- app-hooks/post-installation/10-install-user_oidc-app.sh: Updated dependencies
## Architecture Notes
- MCP Server is a protected resource (requires OAuth)
- MCP Client initiates OAuth flow and shares refresh tokens
- Refresh tokens enable background operations without admin credentials
- Supports future token exchange delegation when Keycloak implements it
## References
- ADR-002: Vector Database Background Sync Authentication
- RFC 6749: OAuth 2.0 (offline_access, refresh tokens)
- RFC 7517: JSON Web Key (JWK)
🤖 Generated with [Claude Code](https://claude.com/claude-code )
Co-Authored-By: Claude <noreply@anthropic.com >
2025-11-02 22:03:19 +01:00
Chris Coutinho
415b1c901b
docs: Parse available scopes from registered tools and update docs
2025-10-25 21:16:40 +02:00
Chris Coutinho
50b69a2531
fix: Add support for RFC 7592 client registration and deletion
2025-10-24 19:19:27 +02:00
Chris Coutinho
8e0a4d8ce5
feat(auth): Add support for client registration deletion
2025-10-24 18:54:24 +02:00
Chris Coutinho
1e877f17f7
test: Replace persistent OAuth client cache with session-scoped fixtures
...
Remove file-based caching of OAuth client credentials and implement automatic
client lifecycle management for test fixtures.
Changes:
- Add RFC 7592 client deletion function in auth/client_registration.py
- Remove cache_file parameter from _create_oauth_client_with_scopes helper
- Update all OAuth credential fixtures to use yield/finalizer pattern
- Add automatic client cleanup at end of test session (best-effort)
- Remove persistent .nextcloud_oauth_*.json cache files
Benefits:
- No persistent cache files cluttering repository
- Fresh OAuth clients created for each test session via DCR
- Automatic cleanup attempts (RFC 7592 DELETE endpoint)
- Cleaner test environment with proper fixture lifecycle
Note: Client deletion may fail due to Nextcloud authentication middleware
(logged as warning). The key improvement is removing persistent cache files.
OAuth clients may accumulate in Nextcloud but can be cleaned manually.
2025-10-24 08:11:22 +02:00
Chris Coutinho
d452684535
feat: Split read/write scopes into app:read/write scopes
2025-10-24 04:38:49 +02:00
Chris Coutinho
bdb0e17401
chore: Add logging to token introspection
2025-10-23 21:18:14 +02:00
Chris Coutinho
e9a16c43b5
refactor: Update JWT client to use DCR, re-enable tool filtering
2025-10-23 09:33:06 +02:00
Chris Coutinho
e48f5f3f30
feat(server): Add support for custom OIDC scopes and permissions via JWTs
2025-10-23 08:37:36 +02:00
Chris Coutinho
c069d78f80
feat: Initialize JWT-scoped tools
2025-10-22 06:21:16 +02:00
Chris Coutinho
63b898c0e3
chore: Update logs
2025-10-20 22:57:18 +02:00
Chris Coutinho
3ad9198f36
fix(oauth): Remove the option to force_register new clients
2025-10-15 16:27:22 +02:00
Chris Coutinho
13e4915e38
test: Remove unused pytest fixtures
2025-10-14 01:23:39 +02:00
Chris Coutinho
f58a9883a6
test: Fix oauth2 token extract from starlette requests
2025-10-14 01:23:37 +02:00
Chris Coutinho
33b962a7fc
test: Setup interactive browser test
2025-10-14 01:23:30 +02:00
Chris Coutinho
4d7e4b9a4b
feat(server): Experimental support for OAuth2/OIDC authentication
2025-10-14 01:22:15 +02:00