Add an admin endpoint to allow authorizing server to signal token revocations (#16125)

2 files changed, 58 insertions, 0 deletions

diff --git a/synapse/rest/admin/__init__.py b/synapse/rest/admin/__init__.py
index fe8177ed4d..55e752fda8 100644
--- a/synapse/rest/admin/__init__.py
+++ b/synapse/rest/admin/__init__.py
@@ -47,6 +47,7 @@ from synapse.rest.admin.federation import (
     ListDestinationsRestServlet,
 )
 from synapse.rest.admin.media import ListMediaInRoom, register_servlets_for_media_repo
+from synapse.rest.admin.oidc import OIDCTokenRevocationRestServlet
 from synapse.rest.admin.registration_tokens import (
     ListRegistrationTokensRestServlet,
     NewRegistrationTokenRestServlet,
@@ -297,6 +298,8 @@ def register_servlets(hs: "HomeServer", http_server: HttpServer) -> None:
     BackgroundUpdateRestServlet(hs).register(http_server)
     BackgroundUpdateStartJobRestServlet(hs).register(http_server)
     ExperimentalFeaturesRestServlet(hs).register(http_server)
+    if hs.config.experimental.msc3861.enabled:
+        OIDCTokenRevocationRestServlet(hs).register(http_server)
 
 
 def register_servlets_for_client_rest_resource(
diff --git a/synapse/rest/admin/oidc.py b/synapse/rest/admin/oidc.py
new file mode 100644
index 0000000000..64d2d40550
--- /dev/null
+++ b/synapse/rest/admin/oidc.py
@@ -0,0 +1,55 @@
+# Copyright 2023 The Matrix.org Foundation C.I.C
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+from http import HTTPStatus
+from typing import TYPE_CHECKING, Dict, Tuple
+
+from synapse.http.servlet import RestServlet
+from synapse.http.site import SynapseRequest
+from synapse.rest.admin._base import admin_patterns, assert_requester_is_admin
+
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
+
+class OIDCTokenRevocationRestServlet(RestServlet):
+    """
+    Delete a given token introspection response - identified by the `jti` field - from the
+    introspection token cache when a token is revoked at the authorizing server
+    """
+
+    PATTERNS = admin_patterns("/OIDC_token_revocation/(?P<token_id>[^/]*)")
+
+    def __init__(self, hs: "HomeServer"):
+        super().__init__()
+        auth = hs.get_auth()
+
+        # If this endpoint is loaded then we must have enabled delegated auth.
+        from synapse.api.auth.msc3861_delegated import MSC3861DelegatedAuth
+
+        assert isinstance(auth, MSC3861DelegatedAuth)
+
+        self.auth = auth
+        self.store = hs.get_datastores().main
+
+    async def on_DELETE(
+        self, request: SynapseRequest, token_id: str
+    ) -> Tuple[HTTPStatus, Dict]:
+        await assert_requester_is_admin(self.auth, request)
+
+        self.auth._token_cache.invalidate(token_id)
+
+        # make sure we invalidate the cache on any workers
+        await self.store.stream_introspection_token_invalidation((token_id,))
+
+        return HTTPStatus.OK, {}