diff options
Diffstat (limited to 'synapse')
| -rw-r--r-- | synapse/config/server.py | 41 | ||||
| -rw-r--r-- | synapse/federation/federation_client.py | 36 | ||||
| -rw-r--r-- | synapse/federation/transport/client.py | 31 | ||||
| -rw-r--r-- | synapse/handlers/federation.py | 25 | ||||
| -rw-r--r-- | synapse/handlers/room_member.py | 84 |
5 files changed, 206 insertions, 11 deletions
diff --git a/synapse/config/server.py b/synapse/config/server.py index 00170f1393..15449695d1 100644 --- a/synapse/config/server.py +++ b/synapse/config/server.py @@ -18,6 +18,7 @@ import logging import os.path +import attr from netaddr import IPSet from synapse.api.room_versions import KNOWN_ROOM_VERSIONS @@ -38,6 +39,12 @@ DEFAULT_BIND_ADDRESSES = ["::", "0.0.0.0"] DEFAULT_ROOM_VERSION = "4" +ROOM_COMPLEXITY_TOO_GREAT = ( + "Your homeserver is unable to join rooms this large or complex. " + "Please speak to your server administrator, or upgrade your instance " + "to join this room." +) + class ServerConfig(Config): def read_config(self, config, **kwargs): @@ -247,6 +254,23 @@ class ServerConfig(Config): self.gc_thresholds = read_gc_thresholds(config.get("gc_thresholds", None)) + @attr.s + class LimitRemoteRoomsConfig(object): + enabled = attr.ib( + validator=attr.validators.instance_of(bool), default=False + ) + complexity = attr.ib( + validator=attr.validators.instance_of((int, float)), default=1.0 + ) + complexity_error = attr.ib( + validator=attr.validators.instance_of(str), + default=ROOM_COMPLEXITY_TOO_GREAT, + ) + + self.limit_remote_rooms = LimitRemoteRoomsConfig( + **config.get("limit_remote_rooms", {}) + ) + bind_port = config.get("bind_port") if bind_port: if config.get("no_tls", False): @@ -617,6 +641,23 @@ class ServerConfig(Config): # Used by phonehome stats to group together related servers. #server_context: context + # Resource-constrained Homeserver Settings + # + # If limit_remote_rooms.enabled is True, the room complexity will be + # checked before a user joins a new remote room. If it is above + # limit_remote_rooms.complexity, it will disallow joining or + # instantly leave. + # + # limit_remote_rooms.complexity_error can be set to customise the text + # displayed to the user when a room above the complexity threshold has + # its join cancelled. + # + # Uncomment the below lines to enable: + #limit_remote_rooms: + # enabled: True + # complexity: 1.0 + # complexity_error: "This room is too complex." + # Whether to require a user to be in the room to add an alias to it. # Defaults to 'true'. # diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index 25ed1257f1..6e03ce21af 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -993,3 +993,39 @@ class FederationClient(FederationBase): ) raise RuntimeError("Failed to send to any server.") + + @defer.inlineCallbacks + def get_room_complexity(self, destination, room_id): + """ + Fetch the complexity of a remote room from another server. + + Args: + destination (str): The remote server + room_id (str): The room ID to ask about. + + Returns: + Deferred[dict] or Deferred[None]: Dict contains the complexity + metric versions, while None means we could not fetch the complexity. + """ + try: + complexity = yield self.transport_layer.get_room_complexity( + destination=destination, room_id=room_id + ) + defer.returnValue(complexity) + except CodeMessageException as e: + # We didn't manage to get it -- probably a 404. We are okay if other + # servers don't give it to us. + logger.debug( + "Failed to fetch room complexity via %s for %s, got a %d", + destination, + room_id, + e.code, + ) + except Exception: + logger.exception( + "Failed to fetch room complexity via %s for %s", destination, room_id + ) + + # If we don't manage to find it, return None. It's not an error if a + # server doesn't give it to us. + defer.returnValue(None) diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py index 2a6709ff48..0cea0d2a10 100644 --- a/synapse/federation/transport/client.py +++ b/synapse/federation/transport/client.py @@ -21,7 +21,11 @@ from six.moves import urllib from twisted.internet import defer from synapse.api.constants import Membership -from synapse.api.urls import FEDERATION_V1_PREFIX, FEDERATION_V2_PREFIX +from synapse.api.urls import ( + FEDERATION_UNSTABLE_PREFIX, + FEDERATION_V1_PREFIX, + FEDERATION_V2_PREFIX, +) from synapse.logging.utils import log_function logger = logging.getLogger(__name__) @@ -935,6 +939,23 @@ class TransportLayerClient(object): destination=destination, path=path, data=content, ignore_backoff=True ) + def get_room_complexity(self, destination, room_id): + """ + Args: + destination (str): The remote server + room_id (str): The room ID to ask about. + """ + path = _create_path(FEDERATION_UNSTABLE_PREFIX, "/rooms/%s/complexity", room_id) + + return self.client.get_json(destination=destination, path=path) + + +def _create_path(federation_prefix, path, *args): + """ + Ensures that all args are url encoded. + """ + return federation_prefix + path % tuple(urllib.parse.quote(arg, "") for arg in args) + def _create_v1_path(path, *args): """Creates a path against V1 federation API from the path template and @@ -951,9 +972,7 @@ def _create_v1_path(path, *args): Returns: str """ - return FEDERATION_V1_PREFIX + path % tuple( - urllib.parse.quote(arg, "") for arg in args - ) + return _create_path(FEDERATION_V1_PREFIX, path, *args) def _create_v2_path(path, *args): @@ -971,6 +990,4 @@ def _create_v2_path(path, *args): Returns: str """ - return FEDERATION_V2_PREFIX + path % tuple( - urllib.parse.quote(arg, "") for arg in args - ) + return _create_path(FEDERATION_V2_PREFIX, path, *args) diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index 89b37dbc1c..10160bfe86 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -2796,3 +2796,28 @@ class FederationHandler(BaseHandler): ) else: return user_joined_room(self.distributor, user, room_id) + + @defer.inlineCallbacks + def get_room_complexity(self, remote_room_hosts, room_id): + """ + Fetch the complexity of a remote room over federation. + + Args: + remote_room_hosts (list[str]): The remote servers to ask. + room_id (str): The room ID to ask about. + + Returns: + Deferred[dict] or Deferred[None]: Dict contains the complexity + metric versions, while None means we could not fetch the complexity. + """ + + for host in remote_room_hosts: + res = yield self.federation_client.get_room_complexity(host, room_id) + + # We got a result, return it. + if res: + defer.returnValue(res) + + # We fell off the bottom, couldn't get the complexity from anyone. Oh + # well. + defer.returnValue(None) diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py index baea08ddd0..249a6d9c5d 100644 --- a/synapse/handlers/room_member.py +++ b/synapse/handlers/room_member.py @@ -26,8 +26,7 @@ from unpaddedbase64 import decode_base64 from twisted.internet import defer -import synapse.server -import synapse.types +from synapse import types from synapse.api.constants import EventTypes, Membership from synapse.api.errors import AuthError, Codes, HttpResponseException, SynapseError from synapse.types import RoomID, UserID @@ -543,7 +542,7 @@ class RoomMemberHandler(object): ), "Sender (%s) must be same as requester (%s)" % (sender, requester.user) assert self.hs.is_mine(sender), "Sender must be our own: %s" % (sender,) else: - requester = synapse.types.create_requester(target_user) + requester = types.create_requester(target_user) prev_event = yield self.event_creation_handler.deduplicate_state_event( event, context @@ -946,13 +945,53 @@ class RoomMemberMasterHandler(RoomMemberHandler): self.distributor.declare("user_left_room") @defer.inlineCallbacks + def _is_remote_room_too_complex(self, room_id, remote_room_hosts): + """ + Check if complexity of a remote room is too great. + + Args: + room_id (str) + remote_room_hosts (list[str]) + + Returns: bool of whether the complexity is too great, or None + if unable to be fetched + """ + max_complexity = self.hs.config.limit_remote_rooms.complexity + complexity = yield self.federation_handler.get_room_complexity( + remote_room_hosts, room_id + ) + + if complexity: + if complexity["v1"] > max_complexity: + return True + return False + return None + + @defer.inlineCallbacks + def _is_local_room_too_complex(self, room_id): + """ + Check if the complexity of a local room is too great. + + Args: + room_id (str) + + Returns: bool + """ + max_complexity = self.hs.config.limit_remote_rooms.complexity + complexity = yield self.store.get_room_complexity(room_id) + + if complexity["v1"] > max_complexity: + return True + + return False + + @defer.inlineCallbacks def _remote_join(self, requester, remote_room_hosts, room_id, user, content): """Implements RoomMemberHandler._remote_join """ # filter ourselves out of remote_room_hosts: do_invite_join ignores it # and if it is the only entry we'd like to return a 404 rather than a # 500. - remote_room_hosts = [ host for host in remote_room_hosts if host != self.hs.hostname ] @@ -960,6 +999,18 @@ class RoomMemberMasterHandler(RoomMemberHandler): if len(remote_room_hosts) == 0: raise SynapseError(404, "No known servers") + if self.hs.config.limit_remote_rooms.enabled: + # Fetch the room complexity + too_complex = yield self._is_remote_room_too_complex( + room_id, remote_room_hosts + ) + if too_complex is True: + raise SynapseError( + code=400, + msg=self.hs.config.limit_remote_rooms.complexity_error, + errcode=Codes.RESOURCE_LIMIT_EXCEEDED, + ) + # We don't do an auth check if we are doing an invite # join dance for now, since we're kinda implicitly checking # that we are allowed to join when we decide whether or not we @@ -969,6 +1020,31 @@ class RoomMemberMasterHandler(RoomMemberHandler): ) yield self._user_joined_room(user, room_id) + # Check the room we just joined wasn't too large, if we didn't fetch the + # complexity of it before. + if self.hs.config.limit_remote_rooms.enabled: + if too_complex is False: + # We checked, and we're under the limit. + return + + # Check again, but with the local state events + too_complex = yield self._is_local_room_too_complex(room_id) + + if too_complex is False: + # We're under the limit. + return + + # The room is too large. Leave. + requester = types.create_requester(user, None, False, None) + yield self.update_membership( + requester=requester, target=user, room_id=room_id, action="leave" + ) + raise SynapseError( + code=400, + msg=self.hs.config.limit_remote_rooms.complexity_error, + errcode=Codes.RESOURCE_LIMIT_EXCEEDED, + ) + @defer.inlineCallbacks def _remote_reject_invite(self, requester, remote_room_hosts, room_id, target): """Implements RoomMemberHandler._remote_reject_invite |