From af784644c3380d0a2ea885abbe748fbe69d3a990 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Tue, 9 Nov 2021 11:45:36 +0000 Subject: [PATCH] Include cross-signing signatures when syncing remote devices for the first time (#11234) When fetching remote devices for the first time, we did not correctly include the cross signing keys in the returned results. c.f. #11159 --- changelog.d/11234.bugfix | 1 + synapse/handlers/e2e_keys.py | 211 +++++++++++++++++++------------- tests/handlers/test_e2e_keys.py | 151 +++++++++++++++++++++++ 3 files changed, 277 insertions(+), 86 deletions(-) create mode 100644 changelog.d/11234.bugfix diff --git a/changelog.d/11234.bugfix b/changelog.d/11234.bugfix new file mode 100644 index 0000000000..c0c02a58f6 --- /dev/null +++ b/changelog.d/11234.bugfix @@ -0,0 +1 @@ +Fix long-standing bug where cross signing keys were not included in the response to `/r0/keys/query` the first time a remote user was queried. diff --git a/synapse/handlers/e2e_keys.py b/synapse/handlers/e2e_keys.py index d0fb2fc7dc..60c11e3d21 100644 --- a/synapse/handlers/e2e_keys.py +++ b/synapse/handlers/e2e_keys.py @@ -201,95 +201,19 @@ class E2eKeysHandler: r[user_id] = remote_queries[user_id] # Now fetch any devices that we don't have in our cache - @trace - async def do_remote_query(destination: str) -> None: - """This is called when we are querying the device list of a user on - a remote homeserver and their device list is not in the device list - cache. If we share a room with this user and we're not querying for - specific user we will update the cache with their device list. - """ - - destination_query = remote_queries_not_in_cache[destination] - - # We first consider whether we wish to update the device list cache with - # the users device list. We want to track a user's devices when the - # authenticated user shares a room with the queried user and the query - # has not specified a particular device. - # If we update the cache for the queried user we remove them from further - # queries. We use the more efficient batched query_client_keys for all - # remaining users - user_ids_updated = [] - for (user_id, device_list) in destination_query.items(): - if user_id in user_ids_updated: - continue - - if device_list: - continue - - room_ids = await self.store.get_rooms_for_user(user_id) - if not room_ids: - continue - - # We've decided we're sharing a room with this user and should - # probably be tracking their device lists. However, we haven't - # done an initial sync on the device list so we do it now. - try: - if self._is_master: - user_devices = await self.device_handler.device_list_updater.user_device_resync( - user_id - ) - else: - user_devices = await self._user_device_resync_client( - user_id=user_id - ) - - user_devices = user_devices["devices"] - user_results = results.setdefault(user_id, {}) - for device in user_devices: - user_results[device["device_id"]] = device["keys"] - user_ids_updated.append(user_id) - except Exception as e: - failures[destination] = _exception_to_failure(e) - - if len(destination_query) == len(user_ids_updated): - # We've updated all the users in the query and we do not need to - # make any further remote calls. - return - - # Remove all the users from the query which we have updated - for user_id in user_ids_updated: - destination_query.pop(user_id) - - try: - remote_result = await self.federation.query_client_keys( - destination, {"device_keys": destination_query}, timeout=timeout - ) - - for user_id, keys in remote_result["device_keys"].items(): - if user_id in destination_query: - results[user_id] = keys - - if "master_keys" in remote_result: - for user_id, key in remote_result["master_keys"].items(): - if user_id in destination_query: - cross_signing_keys["master_keys"][user_id] = key - - if "self_signing_keys" in remote_result: - for user_id, key in remote_result["self_signing_keys"].items(): - if user_id in destination_query: - cross_signing_keys["self_signing_keys"][user_id] = key - - except Exception as e: - failure = _exception_to_failure(e) - failures[destination] = failure - set_tag("error", True) - set_tag("reason", failure) - await make_deferred_yieldable( defer.gatherResults( [ - run_in_background(do_remote_query, destination) - for destination in remote_queries_not_in_cache + run_in_background( + self._query_devices_for_destination, + results, + cross_signing_keys, + failures, + destination, + queries, + timeout, + ) + for destination, queries in remote_queries_not_in_cache.items() ], consumeErrors=True, ).addErrback(unwrapFirstError) @@ -301,6 +225,121 @@ class E2eKeysHandler: return ret + @trace + async def _query_devices_for_destination( + self, + results: JsonDict, + cross_signing_keys: JsonDict, + failures: Dict[str, JsonDict], + destination: str, + destination_query: Dict[str, Iterable[str]], + timeout: int, + ) -> None: + """This is called when we are querying the device list of a user on + a remote homeserver and their device list is not in the device list + cache. If we share a room with this user and we're not querying for + specific user we will update the cache with their device list. + + Args: + results: A map from user ID to their device keys, which gets + updated with the newly fetched keys. + cross_signing_keys: Map from user ID to their cross signing keys, + which gets updated with the newly fetched keys. + failures: Map of destinations to failures that have occurred while + attempting to fetch keys. + destination: The remote server to query + destination_query: The query dict of devices to query the remote + server for. + timeout: The timeout for remote HTTP requests. + """ + + # We first consider whether we wish to update the device list cache with + # the users device list. We want to track a user's devices when the + # authenticated user shares a room with the queried user and the query + # has not specified a particular device. + # If we update the cache for the queried user we remove them from further + # queries. We use the more efficient batched query_client_keys for all + # remaining users + user_ids_updated = [] + for (user_id, device_list) in destination_query.items(): + if user_id in user_ids_updated: + continue + + if device_list: + continue + + room_ids = await self.store.get_rooms_for_user(user_id) + if not room_ids: + continue + + # We've decided we're sharing a room with this user and should + # probably be tracking their device lists. However, we haven't + # done an initial sync on the device list so we do it now. + try: + if self._is_master: + resync_results = await self.device_handler.device_list_updater.user_device_resync( + user_id + ) + else: + resync_results = await self._user_device_resync_client( + user_id=user_id + ) + + # Add the device keys to the results. + user_devices = resync_results["devices"] + user_results = results.setdefault(user_id, {}) + for device in user_devices: + user_results[device["device_id"]] = device["keys"] + user_ids_updated.append(user_id) + + # Add any cross signing keys to the results. + master_key = resync_results.get("master_key") + self_signing_key = resync_results.get("self_signing_key") + + if master_key: + cross_signing_keys["master_keys"][user_id] = master_key + + if self_signing_key: + cross_signing_keys["self_signing_keys"][user_id] = self_signing_key + except Exception as e: + failures[destination] = _exception_to_failure(e) + + if len(destination_query) == len(user_ids_updated): + # We've updated all the users in the query and we do not need to + # make any further remote calls. + return + + # Remove all the users from the query which we have updated + for user_id in user_ids_updated: + destination_query.pop(user_id) + + try: + remote_result = await self.federation.query_client_keys( + destination, {"device_keys": destination_query}, timeout=timeout + ) + + for user_id, keys in remote_result["device_keys"].items(): + if user_id in destination_query: + results[user_id] = keys + + if "master_keys" in remote_result: + for user_id, key in remote_result["master_keys"].items(): + if user_id in destination_query: + cross_signing_keys["master_keys"][user_id] = key + + if "self_signing_keys" in remote_result: + for user_id, key in remote_result["self_signing_keys"].items(): + if user_id in destination_query: + cross_signing_keys["self_signing_keys"][user_id] = key + + except Exception as e: + failure = _exception_to_failure(e) + failures[destination] = failure + set_tag("error", True) + set_tag("reason", failure) + + return + async def get_cross_signing_keys_from_cache( self, query: Iterable[str], from_user_id: Optional[str] ) -> Dict[str, Dict[str, dict]]: diff --git a/tests/handlers/test_e2e_keys.py b/tests/handlers/test_e2e_keys.py index 39e7b1ab25..0c3b86fda9 100644 --- a/tests/handlers/test_e2e_keys.py +++ b/tests/handlers/test_e2e_keys.py @@ -17,6 +17,8 @@ from unittest import mock from signedjson import key as key, sign as sign +from twisted.internet import defer + from synapse.api.constants import RoomEncryptionAlgorithms from synapse.api.errors import Codes, SynapseError @@ -630,3 +632,152 @@ class E2eKeysHandlerTestCase(unittest.HomeserverTestCase): ], other_master_key["signatures"][local_user]["ed25519:" + usersigning_pubkey], ) + + def test_query_devices_remote_no_sync(self): + """Tests that querying keys for a remote user that we don't share a room + with returns the cross signing keys correctly. + """ + + remote_user_id = "@test:other" + local_user_id = "@test:test" + + remote_master_key = "85T7JXPFBAySB/jwby4S3lBPTqY3+Zg53nYuGmu1ggY" + remote_self_signing_key = "QeIiFEjluPBtI7WQdG365QKZcFs9kqmHir6RBD0//nQ" + + self.hs.get_federation_client().query_client_keys = mock.Mock( + return_value=defer.succeed( + { + "device_keys": {remote_user_id: {}}, + "master_keys": { + remote_user_id: { + "user_id": remote_user_id, + "usage": ["master"], + "keys": {"ed25519:" + remote_master_key: remote_master_key}, + }, + }, + "self_signing_keys": { + remote_user_id: { + "user_id": remote_user_id, + "usage": ["self_signing"], + "keys": { + "ed25519:" + + remote_self_signing_key: remote_self_signing_key + }, + } + }, + } + ) + ) + + e2e_handler = self.hs.get_e2e_keys_handler() + + query_result = self.get_success( + e2e_handler.query_devices( + { + "device_keys": {remote_user_id: []}, + }, + timeout=10, + from_user_id=local_user_id, + from_device_id="some_device_id", + ) + ) + + self.assertEqual(query_result["failures"], {}) + self.assertEqual( + query_result["master_keys"], + { + remote_user_id: { + "user_id": remote_user_id, + "usage": ["master"], + "keys": {"ed25519:" + remote_master_key: remote_master_key}, + }, + }, + ) + self.assertEqual( + query_result["self_signing_keys"], + { + remote_user_id: { + "user_id": remote_user_id, + "usage": ["self_signing"], + "keys": { + "ed25519:" + remote_self_signing_key: remote_self_signing_key + }, + } + }, + ) + + def test_query_devices_remote_sync(self): + """Tests that querying keys for a remote user that we share a room with, + but haven't yet fetched the keys for, returns the cross signing keys + correctly. + """ + + remote_user_id = "@test:other" + local_user_id = "@test:test" + + self.store.get_rooms_for_user = mock.Mock( + return_value=defer.succeed({"some_room_id"}) + ) + + remote_master_key = "85T7JXPFBAySB/jwby4S3lBPTqY3+Zg53nYuGmu1ggY" + remote_self_signing_key = "QeIiFEjluPBtI7WQdG365QKZcFs9kqmHir6RBD0//nQ" + + self.hs.get_federation_client().query_user_devices = mock.Mock( + return_value=defer.succeed( + { + "user_id": remote_user_id, + "stream_id": 1, + "devices": [], + "master_key": { + "user_id": remote_user_id, + "usage": ["master"], + "keys": {"ed25519:" + remote_master_key: remote_master_key}, + }, + "self_signing_key": { + "user_id": remote_user_id, + "usage": ["self_signing"], + "keys": { + "ed25519:" + + remote_self_signing_key: remote_self_signing_key + }, + }, + } + ) + ) + + e2e_handler = self.hs.get_e2e_keys_handler() + + query_result = self.get_success( + e2e_handler.query_devices( + { + "device_keys": {remote_user_id: []}, + }, + timeout=10, + from_user_id=local_user_id, + from_device_id="some_device_id", + ) + ) + + self.assertEqual(query_result["failures"], {}) + self.assertEqual( + query_result["master_keys"], + { + remote_user_id: { + "user_id": remote_user_id, + "usage": ["master"], + "keys": {"ed25519:" + remote_master_key: remote_master_key}, + } + }, + ) + self.assertEqual( + query_result["self_signing_keys"], + { + remote_user_id: { + "user_id": remote_user_id, + "usage": ["self_signing"], + "keys": { + "ed25519:" + remote_self_signing_key: remote_self_signing_key + }, + } + }, + )