From 54a51ff6c1a1d9c7174e239acdd2dee7bed744f7 Mon Sep 17 00:00:00 2001 From: Shay Date: Thu, 17 Aug 2023 10:53:10 -0700 Subject: [PATCH] Cache token introspection response from OIDC provider (#16117) --- changelog.d/16117.misc | 1 + synapse/api/auth/msc3861_delegated.py | 40 +++++++++++++++- tests/handlers/test_oauth_delegation.py | 62 +++++++++++++++++++++++++ 3 files changed, 101 insertions(+), 2 deletions(-) create mode 100644 changelog.d/16117.misc diff --git a/changelog.d/16117.misc b/changelog.d/16117.misc new file mode 100644 index 0000000000..f33fa6dc17 --- /dev/null +++ b/changelog.d/16117.misc @@ -0,0 +1 @@ +Cache token introspection response from OIDC provider. diff --git a/synapse/api/auth/msc3861_delegated.py b/synapse/api/auth/msc3861_delegated.py index 9524102a30..3a516093f5 100644 --- a/synapse/api/auth/msc3861_delegated.py +++ b/synapse/api/auth/msc3861_delegated.py @@ -39,6 +39,7 @@ from synapse.logging.context import make_deferred_yieldable from synapse.types import Requester, UserID, create_requester from synapse.util import json_decoder from synapse.util.caches.cached_call import RetryOnExceptionCachedCall +from synapse.util.caches.expiringcache import ExpiringCache if TYPE_CHECKING: from synapse.server import HomeServer @@ -106,6 +107,14 @@ class MSC3861DelegatedAuth(BaseAuth): self._issuer_metadata = RetryOnExceptionCachedCall(self._load_metadata) + self._clock = hs.get_clock() + self._token_cache: ExpiringCache[str, IntrospectionToken] = ExpiringCache( + cache_name="introspection_token_cache", + clock=self._clock, + max_len=10000, + expiry_ms=5 * 60 * 1000, + ) + if isinstance(auth_method, PrivateKeyJWTWithKid): # Use the JWK as the client secret when using the private_key_jwt method assert self._config.jwk, "No JWK provided" @@ -144,6 +153,20 @@ class MSC3861DelegatedAuth(BaseAuth): Returns: The introspection response """ + # check the cache before doing a request + introspection_token = self._token_cache.get(token, None) + + if introspection_token: + # check the expiration field of the token (if it exists) + exp = introspection_token.get("exp", None) + if exp: + time_now = self._clock.time() + expired = time_now > exp + if not expired: + return introspection_token + else: + return introspection_token + metadata = await self._issuer_metadata.get() introspection_endpoint = metadata.get("introspection_endpoint") raw_headers: Dict[str, str] = { @@ -157,7 +180,10 @@ class MSC3861DelegatedAuth(BaseAuth): # Fill the body/headers with credentials uri, raw_headers, body = self._client_auth.prepare( - method="POST", uri=introspection_endpoint, headers=raw_headers, body=body + method="POST", + uri=introspection_endpoint, + headers=raw_headers, + body=body, ) headers = Headers({k: [v] for (k, v) in raw_headers.items()}) @@ -187,7 +213,17 @@ class MSC3861DelegatedAuth(BaseAuth): "The introspection endpoint returned an invalid JSON response." ) - return IntrospectionToken(**resp) + expiration = resp.get("exp", None) + if expiration: + if self._clock.time() > expiration: + raise InvalidClientTokenError("Token is expired.") + + introspection_token = IntrospectionToken(**resp) + + # add token to cache + self._token_cache[token] = introspection_token + + return introspection_token async def is_server_admin(self, requester: Requester) -> bool: return "urn:synapse:admin:*" in requester.scope diff --git a/tests/handlers/test_oauth_delegation.py b/tests/handlers/test_oauth_delegation.py index 6309d7b36e..82c26e303f 100644 --- a/tests/handlers/test_oauth_delegation.py +++ b/tests/handlers/test_oauth_delegation.py @@ -491,6 +491,68 @@ class MSC3861OAuthDelegation(HomeserverTestCase): error = self.get_failure(self.auth.get_user_by_req(request), SynapseError) self.assertEqual(error.value.code, 503) + def test_introspection_token_cache(self) -> None: + access_token = "open_sesame" + self.http_client.request = simple_async_mock( + return_value=FakeResponse.json( + code=200, + payload={"active": "true", "scope": "guest", "jti": access_token}, + ) + ) + + # first call should cache response + # Mpyp ignores below are due to mypy not understanding the dynamic substitution of msc3861 auth code + # for regular auth code via the config + self.get_success( + self.auth._introspect_token(access_token) # type: ignore[attr-defined] + ) + introspection_token = self.auth._token_cache.get(access_token) # type: ignore[attr-defined] + self.assertEqual(introspection_token["jti"], access_token) + # there's been one http request + self.http_client.request.assert_called_once() + + # second call should pull from cache, there should still be only one http request + token = self.get_success(self.auth._introspect_token(access_token)) # type: ignore[attr-defined] + self.http_client.request.assert_called_once() + self.assertEqual(token["jti"], access_token) + + # advance past five minutes and check that cache expired - there should be more than one http call now + self.reactor.advance(360) + token_2 = self.get_success(self.auth._introspect_token(access_token)) # type: ignore[attr-defined] + self.assertEqual(self.http_client.request.call_count, 2) + self.assertEqual(token_2["jti"], access_token) + + # test that if a cached token is expired, a fresh token will be pulled from authorizing server - first add a + # token with a soon-to-expire `exp` field to the cache + self.http_client.request = simple_async_mock( + return_value=FakeResponse.json( + code=200, + payload={ + "active": "true", + "scope": "guest", + "jti": "stale", + "exp": self.clock.time() + 100, + }, + ) + ) + self.get_success( + self.auth._introspect_token("stale") # type: ignore[attr-defined] + ) + introspection_token = self.auth._token_cache.get("stale") # type: ignore[attr-defined] + self.assertEqual(introspection_token["jti"], "stale") + self.assertEqual(self.http_client.request.call_count, 1) + + # advance the reactor past the token expiry but less than the cache expiry + self.reactor.advance(120) + self.assertEqual(self.auth._token_cache.get("stale"), introspection_token) # type: ignore[attr-defined] + + # check that the next call causes another http request (which will fail because the token is technically expired + # but the important thing is we discard the token from the cache and try the network) + self.get_failure( + self.auth._introspect_token("stale"), InvalidClientTokenError # type: ignore[attr-defined] + ) + self.assertEqual(self.http_client.request.call_count, 2) + def make_device_keys(self, user_id: str, device_id: str) -> JsonDict: # We only generate a master key to simplify the test. master_signing_key = generate_signing_key(device_id)