From 85b0bd8fe05ed78548c9b2b0da768927582f7d70 Mon Sep 17 00:00:00 2001 From: Jorik Schellekens Date: Mon, 29 Jul 2019 16:34:44 +0100 Subject: [PATCH] Update the device list cache when keys/query is called (#5693) --- changelog.d/5693.bugfix | 1 + synapse/handlers/device.py | 150 ++++++++++++++++++----------------- synapse/handlers/e2e_keys.py | 60 +++++++++++++- 3 files changed, 137 insertions(+), 74 deletions(-) create mode 100644 changelog.d/5693.bugfix diff --git a/changelog.d/5693.bugfix b/changelog.d/5693.bugfix new file mode 100644 index 0000000000..d6f4e590ae --- /dev/null +++ b/changelog.d/5693.bugfix @@ -0,0 +1 @@ +Fix UISIs during homeserver outage. diff --git a/synapse/handlers/device.py b/synapse/handlers/device.py index d6ab337783..5c1cf83c9d 100644 --- a/synapse/handlers/device.py +++ b/synapse/handlers/device.py @@ -209,12 +209,12 @@ class DeviceHandler(DeviceWorkerHandler): self.federation_sender = hs.get_federation_sender() - self._edu_updater = DeviceListEduUpdater(hs, self) + self.device_list_updater = DeviceListUpdater(hs, self) federation_registry = hs.get_federation_registry() federation_registry.register_edu_handler( - "m.device_list_update", self._edu_updater.incoming_device_list_update + "m.device_list_update", self.device_list_updater.incoming_device_list_update ) federation_registry.register_query_handler( "user_devices", self.on_federation_query_user_devices @@ -426,7 +426,7 @@ def _update_device_from_client_ips(device, client_ips): device.update({"last_seen_ts": ip.get("last_seen"), "last_seen_ip": ip.get("ip")}) -class DeviceListEduUpdater(object): +class DeviceListUpdater(object): "Handles incoming device list updates from federation and updates the DB" def __init__(self, hs, device_handler): @@ -519,75 +519,7 @@ class DeviceListEduUpdater(object): logger.debug("Need to re-sync devices for %r? %r", user_id, resync) if resync: - # Fetch all devices for the user. - origin = get_domain_from_id(user_id) - try: - result = yield self.federation.query_user_devices(origin, user_id) - except ( - NotRetryingDestination, - RequestSendFailed, - HttpResponseException, - ): - # TODO: Remember that we are now out of sync and try again - # later - logger.warn("Failed to handle device list update for %s", user_id) - # We abort on exceptions rather than accepting the update - # as otherwise synapse will 'forget' that its device list - # is out of date. If we bail then we will retry the resync - # next time we get a device list update for this user_id. - # This makes it more likely that the device lists will - # eventually become consistent. - return - except FederationDeniedError as e: - logger.info(e) - return - except Exception: - # TODO: Remember that we are now out of sync and try again - # later - logger.exception( - "Failed to handle device list update for %s", user_id - ) - return - - stream_id = result["stream_id"] - devices = result["devices"] - - # If the remote server has more than ~1000 devices for this user - # we assume that something is going horribly wrong (e.g. a bot - # that logs in and creates a new device every time it tries to - # send a message). Maintaining lots of devices per user in the - # cache can cause serious performance issues as if this request - # takes more than 60s to complete, internal replication from the - # inbound federation worker to the synapse master may time out - # causing the inbound federation to fail and causing the remote - # server to retry, causing a DoS. So in this scenario we give - # up on storing the total list of devices and only handle the - # delta instead. - if len(devices) > 1000: - logger.warn( - "Ignoring device list snapshot for %s as it has >1K devs (%d)", - user_id, - len(devices), - ) - devices = [] - - for device in devices: - logger.debug( - "Handling resync update %r/%r, ID: %r", - user_id, - device["device_id"], - stream_id, - ) - - yield self.store.update_remote_device_list_cache( - user_id, devices, stream_id - ) - device_ids = [device["device_id"] for device in devices] - yield self.device_handler.notify_device_update(user_id, device_ids) - - # We clobber the seen updates since we've re-synced from a given - # point. - self._seen_updates[user_id] = set([stream_id]) + yield self.user_device_resync(user_id) else: # Simply update the single device, since we know that is the only # change (because of the single prev_id matching the current cache) @@ -634,3 +566,77 @@ class DeviceListEduUpdater(object): stream_id_in_updates.add(stream_id) return False + + @defer.inlineCallbacks + def user_device_resync(self, user_id): + """Fetches all devices for a user and updates the device cache with them. + + Args: + user_id (str): The user's id whose device_list will be updated. + Returns: + Deferred[dict]: a dict with device info as under the "devices" in the result of this + request: + https://matrix.org/docs/spec/server_server/r0.1.2#get-matrix-federation-v1-user-devices-userid + """ + # Fetch all devices for the user. + origin = get_domain_from_id(user_id) + try: + result = yield self.federation.query_user_devices(origin, user_id) + except (NotRetryingDestination, RequestSendFailed, HttpResponseException): + # TODO: Remember that we are now out of sync and try again + # later + logger.warn("Failed to handle device list update for %s", user_id) + # We abort on exceptions rather than accepting the update + # as otherwise synapse will 'forget' that its device list + # is out of date. If we bail then we will retry the resync + # next time we get a device list update for this user_id. + # This makes it more likely that the device lists will + # eventually become consistent. + return + except FederationDeniedError as e: + logger.info(e) + return + except Exception: + # TODO: Remember that we are now out of sync and try again + # later + logger.exception("Failed to handle device list update for %s", user_id) + return + stream_id = result["stream_id"] + devices = result["devices"] + + # If the remote server has more than ~1000 devices for this user + # we assume that something is going horribly wrong (e.g. a bot + # that logs in and creates a new device every time it tries to + # send a message). Maintaining lots of devices per user in the + # cache can cause serious performance issues as if this request + # takes more than 60s to complete, internal replication from the + # inbound federation worker to the synapse master may time out + # causing the inbound federation to fail and causing the remote + # server to retry, causing a DoS. So in this scenario we give + # up on storing the total list of devices and only handle the + # delta instead. + if len(devices) > 1000: + logger.warn( + "Ignoring device list snapshot for %s as it has >1K devs (%d)", + user_id, + len(devices), + ) + devices = [] + + for device in devices: + logger.debug( + "Handling resync update %r/%r, ID: %r", + user_id, + device["device_id"], + stream_id, + ) + + yield self.store.update_remote_device_list_cache(user_id, devices, stream_id) + device_ids = [device["device_id"] for device in devices] + yield self.device_handler.notify_device_update(user_id, device_ids) + + # We clobber the seen updates since we've re-synced from a given + # point. + self._seen_updates[user_id] = set([stream_id]) + + defer.returnValue(result) diff --git a/synapse/handlers/e2e_keys.py b/synapse/handlers/e2e_keys.py index 1300b540e3..366a0bc68b 100644 --- a/synapse/handlers/e2e_keys.py +++ b/synapse/handlers/e2e_keys.py @@ -65,6 +65,7 @@ class E2eKeysHandler(object): } } """ + device_keys_query = query_body.get("device_keys", {}) # separate users by domain. @@ -121,7 +122,58 @@ class E2eKeysHandler(object): # Now fetch any devices that we don't have in our cache @defer.inlineCallbacks def do_remote_query(destination): + """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 = yield 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: + user_devices = yield self.device_handler.device_list_updater.user_device_resync( + user_id + ) + user_devices = user_devices["devices"] + for device in user_devices: + results[user_id] = {device["device_id"]: device["keys"]} + user_ids_updated.append(user_id) + except Exception as e: + failures[destination] = failures.get(destination, []).append( + _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 = yield self.federation.query_client_keys( destination, {"device_keys": destination_query}, timeout=timeout @@ -132,7 +184,8 @@ class E2eKeysHandler(object): results[user_id] = keys except Exception as e: - failures[destination] = _exception_to_failure(e) + failure = _exception_to_failure(e) + failures[destination] = failure yield make_deferred_yieldable( defer.gatherResults( @@ -234,8 +287,10 @@ class E2eKeysHandler(object): for user_id, keys in remote_result["one_time_keys"].items(): if user_id in device_keys: json_result[user_id] = keys + except Exception as e: - failures[destination] = _exception_to_failure(e) + failure = _exception_to_failure(e) + failures[destination] = failure yield make_deferred_yieldable( defer.gatherResults( @@ -263,6 +318,7 @@ class E2eKeysHandler(object): @defer.inlineCallbacks def upload_keys_for_user(self, user_id, device_id, keys): + time_now = self.clock.time_msec() # TODO: Validate the JSON to make sure it has the right keys.