# -*- coding: utf-8 -*- # Copyright 2014 - 2016 OpenMarket Ltd # Copyright 2017 - 2018 New Vector Ltd # # 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 twisted.internet import defer from synapse.api.constants import EventTypes, Membership from synapse.api.errors import AuthError, Codes, SynapseError from synapse.crypto.event_signing import add_hashes_and_signatures from synapse.events.utils import serialize_event from synapse.events.validator import EventValidator from synapse.types import ( UserID, RoomAlias, RoomStreamToken, ) from synapse.util.async import run_on_reactor, ReadWriteLock, Limiter from synapse.util.logcontext import preserve_fn from synapse.util.metrics import measure_func from synapse.util.frozenutils import unfreeze from synapse.visibility import filter_events_for_client from ._base import BaseHandler from canonicaljson import encode_canonical_json import logging import random import ujson logger = logging.getLogger(__name__) class MessageHandler(BaseHandler): def __init__(self, hs): super(MessageHandler, self).__init__(hs) self.hs = hs self.state = hs.get_state_handler() self.clock = hs.get_clock() self.pagination_lock = ReadWriteLock() @defer.inlineCallbacks def purge_history(self, room_id, event_id): event = yield self.store.get_event(event_id) if event.room_id != room_id: raise SynapseError(400, "Event is for wrong room.") depth = event.depth with (yield self.pagination_lock.write(room_id)): yield self.store.delete_old_state(room_id, depth) @defer.inlineCallbacks def get_messages(self, requester, room_id=None, pagin_config=None, as_client_event=True, event_filter=None): """Get messages in a room. Args: requester (Requester): The user requesting messages. room_id (str): The room they want messages from. pagin_config (synapse.api.streams.PaginationConfig): The pagination config rules to apply, if any. as_client_event (bool): True to get events in client-server format. event_filter (Filter): Filter to apply to results or None Returns: dict: Pagination API results """ user_id = requester.user.to_string() if pagin_config.from_token: room_token = pagin_config.from_token.room_key else: pagin_config.from_token = ( yield self.hs.get_event_sources().get_current_token_for_room( room_id=room_id ) ) room_token = pagin_config.from_token.room_key room_token = RoomStreamToken.parse(room_token) pagin_config.from_token = pagin_config.from_token.copy_and_replace( "room_key", str(room_token) ) source_config = pagin_config.get_source_config("room") with (yield self.pagination_lock.read(room_id)): membership, member_event_id = yield self._check_in_room_or_world_readable( room_id, user_id ) if source_config.direction == 'b': # if we're going backwards, we might need to backfill. This # requires that we have a topo token. if room_token.topological: max_topo = room_token.topological else: max_topo = yield self.store.get_max_topological_token( room_id, room_token.stream ) if membership == Membership.LEAVE: # If they have left the room then clamp the token to be before # they left the room, to save the effort of loading from the # database. leave_token = yield self.store.get_topological_token_for_event( member_event_id ) leave_token = RoomStreamToken.parse(leave_token) if leave_token.topological < max_topo: source_config.from_key = str(leave_token) yield self.hs.get_handlers().federation_handler.maybe_backfill( room_id, max_topo ) events, next_key = yield self.store.paginate_room_events( room_id=room_id, from_key=source_config.from_key, to_key=source_config.to_key, direction=source_config.direction, limit=source_config.limit, event_filter=event_filter, ) next_token = pagin_config.from_token.copy_and_replace( "room_key", next_key ) if not events: defer.returnValue({ "chunk": [], "start": pagin_config.from_token.to_string(), "end": next_token.to_string(), }) if event_filter: events = event_filter.filter(events) events = yield filter_events_for_client( self.store, user_id, events, is_peeking=(member_event_id is None), ) time_now = self.clock.time_msec() chunk = { "chunk": [ serialize_event(e, time_now, as_client_event) for e in events ], "start": pagin_config.from_token.to_string(), "end": next_token.to_string(), } defer.returnValue(chunk) @defer.inlineCallbacks def get_room_data(self, user_id=None, room_id=None, event_type=None, state_key="", is_guest=False): """ Get data from a room. Args: event : The room path event Returns: The path data content. Raises: SynapseError if something went wrong. """ membership, membership_event_id = yield self._check_in_room_or_world_readable( room_id, user_id ) if membership == Membership.JOIN: data = yield self.state_handler.get_current_state( room_id, event_type, state_key ) elif membership == Membership.LEAVE: key = (event_type, state_key) room_state = yield self.store.get_state_for_events( [membership_event_id], [key] ) data = room_state[membership_event_id].get(key) defer.returnValue(data) @defer.inlineCallbacks def _check_in_room_or_world_readable(self, room_id, user_id): try: # check_user_was_in_room will return the most recent membership # event for the user if: # * The user is a non-guest user, and was ever in the room # * The user is a guest user, and has joined the room # else it will throw. member_event = yield self.auth.check_user_was_in_room(room_id, user_id) defer.returnValue((member_event.membership, member_event.event_id)) return except AuthError: visibility = yield self.state_handler.get_current_state( room_id, EventTypes.RoomHistoryVisibility, "" ) if ( visibility and visibility.content["history_visibility"] == "world_readable" ): defer.returnValue((Membership.JOIN, None)) return raise AuthError( 403, "Guest access not allowed", errcode=Codes.GUEST_ACCESS_FORBIDDEN ) @defer.inlineCallbacks def get_state_events(self, user_id, room_id, is_guest=False): """Retrieve all state events for a given room. If the user is joined to the room then return the current state. If the user has left the room return the state events from when they left. Args: user_id(str): The user requesting state events. room_id(str): The room ID to get all state events from. Returns: A list of dicts representing state events. [{}, {}, {}] """ membership, membership_event_id = yield self._check_in_room_or_world_readable( room_id, user_id ) if membership == Membership.JOIN: room_state = yield self.state_handler.get_current_state(room_id) elif membership == Membership.LEAVE: room_state = yield self.store.get_state_for_events( [membership_event_id], None ) room_state = room_state[membership_event_id] now = self.clock.time_msec() defer.returnValue( [serialize_event(c, now) for c in room_state.values()] ) @defer.inlineCallbacks def get_joined_members(self, requester, room_id): """Get all the joined members in the room and their profile information. If the user has left the room return the state events from when they left. Args: requester(Requester): The user requesting state events. room_id(str): The room ID to get all state events from. Returns: A dict of user_id to profile info """ user_id = requester.user.to_string() if not requester.app_service: # We check AS auth after fetching the room membership, as it # requires us to pull out all joined members anyway. membership, _ = yield self._check_in_room_or_world_readable( room_id, user_id ) if membership != Membership.JOIN: raise NotImplementedError( "Getting joined members after leaving is not implemented" ) users_with_profile = yield self.state.get_current_user_in_room(room_id) # If this is an AS, double check that they are allowed to see the members. # This can either be because the AS user is in the room or becuase there # is a user in the room that the AS is "interested in" if requester.app_service and user_id not in users_with_profile: for uid in users_with_profile: if requester.app_service.is_interested_in_user(uid): break else: # Loop fell through, AS has no interested users in room raise AuthError(403, "Appservice not in room") defer.returnValue({ user_id: { "avatar_url": profile.avatar_url, "display_name": profile.display_name, } for user_id, profile in users_with_profile.iteritems() }) class EventCreationHandler(object): def __init__(self, hs): self.hs = hs self.auth = hs.get_auth() self.store = hs.get_datastore() self.state = hs.get_state_handler() self.clock = hs.get_clock() self.validator = EventValidator() self.profile_handler = hs.get_profile_handler() self.event_builder_factory = hs.get_event_builder_factory() self.server_name = hs.hostname self.ratelimiter = hs.get_ratelimiter() self.notifier = hs.get_notifier() # This is only used to get at ratelimit function, and maybe_kick_guest_users self.base_handler = BaseHandler(hs) self.pusher_pool = hs.get_pusherpool() # We arbitrarily limit concurrent event creation for a room to 5. # This is to stop us from diverging history *too* much. self.limiter = Limiter(max_count=5) self.action_generator = hs.get_action_generator() self.spam_checker = hs.get_spam_checker() @defer.inlineCallbacks def create_event(self, requester, event_dict, token_id=None, txn_id=None, prev_event_ids=None): """ Given a dict from a client, create a new event. Creates an FrozenEvent object, filling out auth_events, prev_events, etc. Adds display names to Join membership events. Args: requester event_dict (dict): An entire event token_id (str) txn_id (str) prev_event_ids (list): The prev event ids to use when creating the event Returns: Tuple of created event (FrozenEvent), Context """ builder = self.event_builder_factory.new(event_dict) with (yield self.limiter.queue(builder.room_id)): self.validator.validate_new(builder) if builder.type == EventTypes.Member: membership = builder.content.get("membership", None) target = UserID.from_string(builder.state_key) if membership in {Membership.JOIN, Membership.INVITE}: # If event doesn't include a display name, add one. profile = self.profile_handler content = builder.content try: if "displayname" not in content: content["displayname"] = yield profile.get_displayname(target) if "avatar_url" not in content: content["avatar_url"] = yield profile.get_avatar_url(target) except Exception as e: logger.info( "Failed to get profile information for %r: %s", target, e ) if token_id is not None: builder.internal_metadata.token_id = token_id if txn_id is not None: builder.internal_metadata.txn_id = txn_id event, context = yield self.create_new_client_event( builder=builder, requester=requester, prev_event_ids=prev_event_ids, ) defer.returnValue((event, context)) @defer.inlineCallbacks def send_nonmember_event(self, requester, event, context, ratelimit=True): """ Persists and notifies local clients and federation of an event. Args: event (FrozenEvent) the event to send. context (Context) the context of the event. ratelimit (bool): Whether to rate limit this send. is_guest (bool): Whether the sender is a guest. """ if event.type == EventTypes.Member: raise SynapseError( 500, "Tried to send member event through non-member codepath" ) # We check here if we are currently being rate limited, so that we # don't do unnecessary work. We check again just before we actually # send the event. yield self.base_handler.ratelimit(requester, update=False) user = UserID.from_string(event.sender) assert self.hs.is_mine(user), "User must be our own: %s" % (user,) if event.is_state(): prev_state = yield self.deduplicate_state_event(event, context) if prev_state is not None: defer.returnValue(prev_state) yield self.handle_new_client_event( requester=requester, event=event, context=context, ratelimit=ratelimit, ) if event.type == EventTypes.Message: presence = self.hs.get_presence_handler() # We don't want to block sending messages on any presence code. This # matters as sometimes presence code can take a while. preserve_fn(presence.bump_presence_active_time)(user) @defer.inlineCallbacks def deduplicate_state_event(self, event, context): """ Checks whether event is in the latest resolved state in context. If so, returns the version of the event in context. Otherwise, returns None. """ prev_event_id = context.prev_state_ids.get((event.type, event.state_key)) prev_event = yield self.store.get_event(prev_event_id, allow_none=True) if not prev_event: return if prev_event and event.user_id == prev_event.user_id: prev_content = encode_canonical_json(prev_event.content) next_content = encode_canonical_json(event.content) if prev_content == next_content: defer.returnValue(prev_event) return @defer.inlineCallbacks def create_and_send_nonmember_event( self, requester, event_dict, ratelimit=True, txn_id=None ): """ Creates an event, then sends it. See self.create_event and self.send_nonmember_event. """ event, context = yield self.create_event( requester, event_dict, token_id=requester.access_token_id, txn_id=txn_id ) spam_error = self.spam_checker.check_event_for_spam(event) if spam_error: if not isinstance(spam_error, basestring): spam_error = "Spam is not permitted here" raise SynapseError( 403, spam_error, Codes.FORBIDDEN ) yield self.send_nonmember_event( requester, event, context, ratelimit=ratelimit, ) defer.returnValue(event) @measure_func("create_new_client_event") @defer.inlineCallbacks def create_new_client_event(self, builder, requester=None, prev_event_ids=None): if prev_event_ids: prev_events = yield self.store.add_event_hashes(prev_event_ids) prev_max_depth = yield self.store.get_max_depth_of_events(prev_event_ids) depth = prev_max_depth + 1 else: latest_ret = yield self.store.get_latest_event_ids_and_hashes_in_room( builder.room_id, ) # We want to limit the max number of prev events we point to in our # new event if len(latest_ret) > 10: # Sort by reverse depth, so we point to the most recent. latest_ret.sort(key=lambda a: -a[2]) new_latest_ret = latest_ret[:5] # We also randomly point to some of the older events, to make # sure that we don't completely ignore the older events. if latest_ret[5:]: sample_size = min(5, len(latest_ret[5:])) new_latest_ret.extend(random.sample(latest_ret[5:], sample_size)) latest_ret = new_latest_ret if latest_ret: depth = max([d for _, _, d in latest_ret]) + 1 else: depth = 1 prev_events = [ (event_id, prev_hashes) for event_id, prev_hashes, _ in latest_ret ] builder.prev_events = prev_events builder.depth = depth context = yield self.state.compute_event_context(builder) if requester: context.app_service = requester.app_service if builder.is_state(): builder.prev_state = yield self.store.add_event_hashes( context.prev_state_events ) yield self.auth.add_auth_events(builder, context) signing_key = self.hs.config.signing_key[0] add_hashes_and_signatures( builder, self.server_name, signing_key ) event = builder.build() logger.debug( "Created event %s with state: %s", event.event_id, context.prev_state_ids, ) defer.returnValue( (event, context,) ) @measure_func("handle_new_client_event") @defer.inlineCallbacks def handle_new_client_event( self, requester, event, context, ratelimit=True, extra_users=[] ): # We now need to go and hit out to wherever we need to hit out to. if ratelimit: yield self.base_handler.ratelimit(requester) try: yield self.auth.check_from_context(event, context) except AuthError as err: logger.warn("Denying new event %r because %s", event, err) raise err # Ensure that we can round trip before trying to persist in db try: dump = ujson.dumps(unfreeze(event.content)) ujson.loads(dump) except Exception: logger.exception("Failed to encode content: %r", event.content) raise yield self.base_handler.maybe_kick_guest_users(event, context) if event.type == EventTypes.CanonicalAlias: # Check the alias is acually valid (at this time at least) room_alias_str = event.content.get("alias", None) if room_alias_str: room_alias = RoomAlias.from_string(room_alias_str) directory_handler = self.hs.get_handlers().directory_handler mapping = yield directory_handler.get_association(room_alias) if mapping["room_id"] != event.room_id: raise SynapseError( 400, "Room alias %s does not point to the room" % ( room_alias_str, ) ) federation_handler = self.hs.get_handlers().federation_handler if event.type == EventTypes.Member: if event.content["membership"] == Membership.INVITE: def is_inviter_member_event(e): return ( e.type == EventTypes.Member and e.sender == event.sender ) state_to_include_ids = [ e_id for k, e_id in context.current_state_ids.iteritems() if k[0] in self.hs.config.room_invite_state_types or k == (EventTypes.Member, event.sender) ] state_to_include = yield self.store.get_events(state_to_include_ids) event.unsigned["invite_room_state"] = [ { "type": e.type, "state_key": e.state_key, "content": e.content, "sender": e.sender, } for e in state_to_include.itervalues() ] invitee = UserID.from_string(event.state_key) if not self.hs.is_mine(invitee): # TODO: Can we add signature from remote server in a nicer # way? If we have been invited by a remote server, we need # to get them to sign the event. returned_invite = yield federation_handler.send_invite( invitee.domain, event, ) event.unsigned.pop("room_state", None) # TODO: Make sure the signatures actually are correct. event.signatures.update( returned_invite.signatures ) if event.type == EventTypes.Redaction: auth_events_ids = yield self.auth.compute_auth_events( event, context.prev_state_ids, for_verification=True, ) auth_events = yield self.store.get_events(auth_events_ids) auth_events = { (e.type, e.state_key): e for e in auth_events.values() } if self.auth.check_redaction(event, auth_events=auth_events): original_event = yield self.store.get_event( event.redacts, check_redacted=False, get_prev_content=False, allow_rejected=False, allow_none=False ) if event.user_id != original_event.user_id: raise AuthError( 403, "You don't have permission to redact events" ) if event.type == EventTypes.Create and context.prev_state_ids: raise AuthError( 403, "Changing the room create event is forbidden", ) yield self.action_generator.handle_push_actions_for_event( event, context ) (event_stream_id, max_stream_id) = yield self.store.persist_event( event, context=context ) # this intentionally does not yield: we don't care about the result # and don't need to wait for it. preserve_fn(self.pusher_pool.on_new_notifications)( event_stream_id, max_stream_id ) @defer.inlineCallbacks def _notify(): yield run_on_reactor() self.notifier.on_new_room_event( event, event_stream_id, max_stream_id, extra_users=extra_users ) preserve_fn(_notify)()