diff options
Diffstat (limited to 'synapse/handlers/message.py')
| -rw-r--r-- | synapse/handlers/message.py | 381 |
1 files changed, 238 insertions, 143 deletions
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py index ee271e85e5..96843338ae 100644 --- a/synapse/handlers/message.py +++ b/synapse/handlers/message.py @@ -50,15 +50,15 @@ from synapse.replication.http.send_event import ReplicationSendEventRestServlet from synapse.storage.databases.main.events_worker import EventRedactBehaviour from synapse.storage.state import StateFilter from synapse.types import Requester, RoomAlias, StreamToken, UserID, create_requester -from synapse.util import json_decoder +from synapse.util import json_decoder, json_encoder from synapse.util.async_helpers import Linearizer -from synapse.util.frozenutils import frozendict_json_encoder from synapse.util.metrics import measure_func from synapse.visibility import filter_events_for_client from ._base import BaseHandler if TYPE_CHECKING: + from synapse.events.third_party_rules import ThirdPartyEventRules from synapse.server import HomeServer logger = logging.getLogger(__name__) @@ -393,27 +393,31 @@ class EventCreationHandler: self.action_generator = hs.get_action_generator() self.spam_checker = hs.get_spam_checker() - self.third_party_event_rules = hs.get_third_party_event_rules() + self.third_party_event_rules = ( + self.hs.get_third_party_event_rules() + ) # type: ThirdPartyEventRules self._block_events_without_consent_error = ( self.config.block_events_without_consent_error ) + # we need to construct a ConsentURIBuilder here, as it checks that the necessary + # config options, but *only* if we have a configuration for which we are + # going to need it. + if self._block_events_without_consent_error: + self._consent_uri_builder = ConsentURIBuilder(self.config) + # Rooms which should be excluded from dummy insertion. (For instance, # those without local users who can send events into the room). # # map from room id to time-of-last-attempt. # self._rooms_to_exclude_from_dummy_event_insertion = {} # type: Dict[str, int] - - # we need to construct a ConsentURIBuilder here, as it checks that the necessary - # config options, but *only* if we have a configuration for which we are - # going to need it. - if self._block_events_without_consent_error: - self._consent_uri_builder = ConsentURIBuilder(self.config) + # The number of forward extremeities before a dummy event is sent. + self._dummy_events_threshold = hs.config.dummy_events_threshold if ( - not self.config.worker_app + self.config.run_background_tasks and self.config.cleanup_extremities_with_dummy_events ): self.clock.looping_call( @@ -428,15 +432,13 @@ class EventCreationHandler: self._ephemeral_events_enabled = hs.config.enable_ephemeral_messages - self._dummy_events_threshold = hs.config.dummy_events_threshold - async def create_event( self, requester: Requester, event_dict: dict, - token_id: Optional[str] = None, txn_id: Optional[str] = None, prev_event_ids: Optional[List[str]] = None, + auth_event_ids: Optional[List[str]] = None, require_consent: bool = True, ) -> Tuple[EventBase, EventContext]: """ @@ -450,13 +452,18 @@ class EventCreationHandler: Args: requester event_dict: An entire event - token_id txn_id prev_event_ids: the forward extremities to use as the prev_events for the new event. If None, they will be requested from the database. + + auth_event_ids: + The event ids to use as the auth_events for the new event. + Should normally be left as None, which will cause them to be calculated + based on the room state at the prev_events. + require_consent: Whether to check if the requester has consented to the privacy policy. Raises: @@ -465,7 +472,7 @@ class EventCreationHandler: Returns: Tuple of created event, Context """ - await self.auth.check_auth_blocking(requester.user.to_string()) + await self.auth.check_auth_blocking(requester=requester) if event_dict["type"] == EventTypes.Create and event_dict["state_key"] == "": room_version = event_dict["content"]["room_version"] @@ -508,14 +515,17 @@ class EventCreationHandler: if require_consent and not is_exempt: await self.assert_accepted_privacy_policy(requester) - if token_id is not None: - builder.internal_metadata.token_id = token_id + if requester.access_token_id is not None: + builder.internal_metadata.token_id = requester.access_token_id if txn_id is not None: builder.internal_metadata.txn_id = txn_id event, context = await self.create_new_client_event( - builder=builder, requester=requester, prev_event_ids=prev_event_ids, + builder=builder, + requester=requester, + prev_event_ids=prev_event_ids, + auth_event_ids=auth_event_ids, ) # In an ideal world we wouldn't need the second part of this condition. However, @@ -609,7 +619,13 @@ class EventCreationHandler: if requester.app_service is not None: return - user_id = requester.user.to_string() + user_id = requester.authenticated_entity + if not user_id.startswith("@"): + # The authenticated entity might not be a user, e.g. if it's the + # server puppetting the user. + return + + user = UserID.from_string(user_id) # exempt the system notices user if ( @@ -629,65 +645,10 @@ class EventCreationHandler: if u["consent_version"] == self.config.user_consent_version: return - consent_uri = self._consent_uri_builder.build_user_consent_uri( - requester.user.localpart - ) + consent_uri = self._consent_uri_builder.build_user_consent_uri(user.localpart) msg = self._block_events_without_consent_error % {"consent_uri": consent_uri} raise ConsentNotGivenError(msg=msg, consent_uri=consent_uri) - async def send_nonmember_event( - self, - requester: Requester, - event: EventBase, - context: EventContext, - ratelimit: bool = True, - ignore_shadow_ban: bool = False, - ) -> int: - """ - Persists and notifies local clients and federation of an event. - - Args: - requester: The requester sending the event. - event: The event to send. - context: The context of the event. - ratelimit: Whether to rate limit this send. - ignore_shadow_ban: True if shadow-banned users should be allowed to - send this event. - - Return: - The stream_id of the persisted event. - - Raises: - ShadowBanError if the requester has been shadow-banned. - """ - if event.type == EventTypes.Member: - raise SynapseError( - 500, "Tried to send member event through non-member codepath" - ) - - if not ignore_shadow_ban and requester.shadow_banned: - # We randomly sleep a bit just to annoy the requester. - await self.clock.sleep(random.randint(1, 10)) - raise ShadowBanError() - - user = UserID.from_string(event.sender) - - assert self.hs.is_mine(user), "User must be our own: %s" % (user,) - - if event.is_state(): - prev_event = await self.deduplicate_state_event(event, context) - if prev_event is not None: - logger.info( - "Not bothering to persist state event %s duplicated by %s", - event.event_id, - prev_event.event_id, - ) - return await self.store.get_stream_id_for_event(prev_event.event_id) - - return await self.handle_new_client_event( - requester=requester, event=event, context=context, ratelimit=ratelimit - ) - async def deduplicate_state_event( self, event: EventBase, context: EventContext ) -> Optional[EventBase]: @@ -699,7 +660,7 @@ class EventCreationHandler: context: The event context. Returns: - The previous verion of the event is returned, if it is found in the + The previous version of the event is returned, if it is found in the event context. Otherwise, None is returned. """ prev_state_ids = await context.get_prev_state_ids() @@ -728,7 +689,7 @@ class EventCreationHandler: """ Creates an event, then sends it. - See self.create_event and self.send_nonmember_event. + See self.create_event and self.handle_new_client_event. Args: requester: The requester sending the event. @@ -738,9 +699,19 @@ class EventCreationHandler: ignore_shadow_ban: True if shadow-banned users should be allowed to send this event. + Returns: + The event, and its stream ordering (if deduplication happened, + the previous, duplicate event). + Raises: ShadowBanError if the requester has been shadow-banned. """ + + if event_dict["type"] == EventTypes.Member: + raise SynapseError( + 500, "Tried to send member event through non-member codepath" + ) + if not ignore_shadow_ban and requester.shadow_banned: # We randomly sleep a bit just to annoy the requester. await self.clock.sleep(random.randint(1, 10)) @@ -752,8 +723,25 @@ class EventCreationHandler: # extremities to pile up, which in turn leads to state resolution # taking longer. with (await self.limiter.queue(event_dict["room_id"])): + if txn_id and requester.access_token_id: + existing_event_id = await self.store.get_event_id_from_transaction_id( + event_dict["room_id"], + requester.user.to_string(), + requester.access_token_id, + txn_id, + ) + if existing_event_id: + event = await self.store.get_event(existing_event_id) + # we know it was persisted, so must have a stream ordering + assert event.internal_metadata.stream_ordering + return event, event.internal_metadata.stream_ordering + event, context = await self.create_event( - requester, event_dict, token_id=requester.access_token_id, txn_id=txn_id + requester, event_dict, txn_id=txn_id + ) + + assert self.hs.is_mine_id(event.sender), "User must be our own: %s" % ( + event.sender, ) spam_error = self.spam_checker.check_event_for_spam(event) @@ -762,14 +750,17 @@ class EventCreationHandler: spam_error = "Spam is not permitted here" raise SynapseError(403, spam_error, Codes.FORBIDDEN) - stream_id = await self.send_nonmember_event( - requester, - event, - context, + ev = await self.handle_new_client_event( + requester=requester, + event=event, + context=context, ratelimit=ratelimit, ignore_shadow_ban=ignore_shadow_ban, ) - return event, stream_id + + # we know it was persisted, so must have a stream ordering + assert ev.internal_metadata.stream_ordering + return ev, ev.internal_metadata.stream_ordering @measure_func("create_new_client_event") async def create_new_client_event( @@ -777,6 +768,7 @@ class EventCreationHandler: builder: EventBuilder, requester: Optional[Requester] = None, prev_event_ids: Optional[List[str]] = None, + auth_event_ids: Optional[List[str]] = None, ) -> Tuple[EventBase, EventContext]: """Create a new event for a local client @@ -789,6 +781,11 @@ class EventCreationHandler: If None, they will be requested from the database. + auth_event_ids: + The event ids to use as the auth_events for the new event. + Should normally be left as None, which will cause them to be calculated + based on the room state at the prev_events. + Returns: Tuple of created event, context """ @@ -810,11 +807,30 @@ class EventCreationHandler: builder.type == EventTypes.Create or len(prev_event_ids) > 0 ), "Attempting to create an event with no prev_events" - event = await builder.build(prev_event_ids=prev_event_ids) + event = await builder.build( + prev_event_ids=prev_event_ids, auth_event_ids=auth_event_ids + ) context = await self.state.compute_event_context(event) if requester: context.app_service = requester.app_service + third_party_result = await self.third_party_event_rules.check_event_allowed( + event, context + ) + if not third_party_result: + logger.info( + "Event %s forbidden by third-party rules", event, + ) + raise SynapseError( + 403, "This event is not allowed in this context", Codes.FORBIDDEN + ) + elif isinstance(third_party_result, dict): + # the third-party rules want to replace the event. We'll need to build a new + # event. + event, context = await self._rebuild_event_after_third_party_rules( + third_party_result, event + ) + self.validator.validate_new(event, self.config) # If this event is an annotation then we check that that the sender @@ -843,8 +859,11 @@ class EventCreationHandler: context: EventContext, ratelimit: bool = True, extra_users: List[UserID] = [], - ) -> int: - """Processes a new event. This includes checking auth, persisting it, + ignore_shadow_ban: bool = False, + ) -> EventBase: + """Processes a new event. + + This includes deduplicating, checking auth, persisting, notifying users, sending to remote servers, etc. If called from a worker will hit out to the master process for final @@ -857,10 +876,39 @@ class EventCreationHandler: ratelimit extra_users: Any extra users to notify about event + ignore_shadow_ban: True if shadow-banned users should be allowed to + send this event. + Return: - The stream_id of the persisted event. + If the event was deduplicated, the previous, duplicate, event. Otherwise, + `event`. + + Raises: + ShadowBanError if the requester has been shadow-banned. """ + # we don't apply shadow-banning to membership events here. Invites are blocked + # higher up the stack, and we allow shadow-banned users to send join and leave + # events as normal. + if ( + event.type != EventTypes.Member + and not ignore_shadow_ban + and requester.shadow_banned + ): + # We randomly sleep a bit just to annoy the requester. + await self.clock.sleep(random.randint(1, 10)) + raise ShadowBanError() + + if event.is_state(): + prev_event = await self.deduplicate_state_event(event, context) + if prev_event is not None: + logger.info( + "Not bothering to persist state event %s duplicated by %s", + event.event_id, + prev_event.event_id, + ) + return prev_event + if event.is_state() and (event.type, event.state_key) == ( EventTypes.Create, "", @@ -869,14 +917,6 @@ class EventCreationHandler: else: room_version = await self.store.get_room_version_id(event.room_id) - event_allowed = await self.third_party_event_rules.check_event_allowed( - event, context - ) - if not event_allowed: - raise SynapseError( - 403, "This event is not allowed in this context", Codes.FORBIDDEN - ) - if event.internal_metadata.is_out_of_band_membership(): # the only sort of out-of-band-membership events we expect to see here # are invite rejections we have generated ourselves. @@ -891,7 +931,7 @@ class EventCreationHandler: # Ensure that we can round trip before trying to persist in db try: - dump = frozendict_json_encoder.encode(event.content) + dump = json_encoder.encode(event.content) json_decoder.decode(dump) except Exception: logger.exception("Failed to encode content: %r", event.content) @@ -914,14 +954,24 @@ class EventCreationHandler: extra_users=extra_users, ) stream_id = result["stream_id"] - event.internal_metadata.stream_ordering = stream_id - return stream_id - - stream_id = await self.persist_and_notify_client_event( + event_id = result["event_id"] + if event_id != event.event_id: + # If we get a different event back then it means that its + # been de-duplicated, so we replace the given event with the + # one already persisted. + event = await self.store.get_event(event_id) + else: + # If we newly persisted the event then we need to update its + # stream_ordering entry manually (as it was persisted on + # another worker). + event.internal_metadata.stream_ordering = stream_id + return event + + event = await self.persist_and_notify_client_event( requester, event, context, ratelimit=ratelimit, extra_users=extra_users ) - return stream_id + return event except Exception: # Ensure that we actually remove the entries in the push actions # staging area, if we calculated them. @@ -966,11 +1016,16 @@ class EventCreationHandler: context: EventContext, ratelimit: bool = True, extra_users: List[UserID] = [], - ) -> int: + ) -> EventBase: """Called when we have fully built the event, have already calculated the push actions for the event, and checked auth. This should only be run on the instance in charge of persisting events. + + Returns: + The persisted event. This may be different than the given event if + it was de-duplicated (e.g. because we had already persisted an + event with the same transaction ID.) """ assert self.storage.persistence is not None assert self._events_shard_config.should_handle( @@ -1018,7 +1073,7 @@ class EventCreationHandler: # Check the alias is currently valid (if it has changed). room_alias_str = event.content.get("alias", None) - directory_handler = self.hs.get_handlers().directory_handler + directory_handler = self.hs.get_directory_handler() if room_alias_str and room_alias_str != original_alias: await self._validate_canonical_alias( directory_handler, room_alias_str, event.room_id @@ -1044,38 +1099,17 @@ class EventCreationHandler: directory_handler, alias_str, event.room_id ) - federation_handler = self.hs.get_handlers().federation_handler + federation_handler = self.hs.get_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 - - current_state_ids = await context.get_current_state_ids() - - # We know this event is not an outlier, so this must be - # non-None. - assert current_state_ids is not None - - state_to_include_ids = [ - e_id - for k, e_id in current_state_ids.items() - if k[0] in self.room_invite_state_types - or k == (EventTypes.Member, event.sender) - ] - - state_to_include = await 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.values() - ] + event.unsigned[ + "invite_room_state" + ] = await self.store.get_stripped_room_state_from_event_context( + context, + self.room_invite_state_types, + membership_user_id=event.sender, + ) invitee = UserID.from_string(event.state_key) if not self.hs.is_mine(invitee): @@ -1108,6 +1142,9 @@ class EventCreationHandler: if original_event.room_id != event.room_id: raise SynapseError(400, "Cannot redact event from a different room") + if original_event.type == EventTypes.ServerACL: + raise AuthError(403, "Redacting server ACL events is not permitted") + prev_state_ids = await context.get_prev_state_ids() auth_events_ids = self.auth.compute_auth_events( event, prev_state_ids, for_verification=True @@ -1138,9 +1175,13 @@ class EventCreationHandler: if prev_state_ids: raise AuthError(403, "Changing the room create event is forbidden") - event_pos, max_stream_token = await self.storage.persistence.persist_event( - event, context=context - ) + # Note that this returns the event that was persisted, which may not be + # the same as we passed in if it was deduplicated due transaction IDs. + ( + event, + event_pos, + max_stream_token, + ) = await self.storage.persistence.persist_event(event, context=context) if self._ephemeral_events_enabled: # If there's an expiry timestamp on the event, schedule its expiry. @@ -1161,7 +1202,7 @@ class EventCreationHandler: # matters as sometimes presence code can take a while. run_in_background(self._bump_active_time, requester.user) - return event_pos.stream + return event async def _bump_active_time(self, user: UserID) -> None: try: @@ -1215,7 +1256,7 @@ class EventCreationHandler: for user_id in members: if not self.hs.is_mine_id(user_id): continue - requester = create_requester(user_id) + requester = create_requester(user_id, authenticated_entity=self.server_name) try: event, context = await self.create_event( requester, @@ -1232,15 +1273,10 @@ class EventCreationHandler: # Since this is a dummy-event it is OK if it is sent by a # shadow-banned user. - await self.send_nonmember_event( + await self.handle_new_client_event( requester, event, context, ratelimit=False, ignore_shadow_ban=True, ) return True - except ConsentNotGivenError: - logger.info( - "Failed to send dummy event into room %s for user %s due to " - "lack of consent. Will try another user" % (room_id, user_id) - ) except AuthError: logger.info( "Failed to send dummy event into room %s for user %s due to " @@ -1260,3 +1296,62 @@ class EventCreationHandler: room_id, ) del self._rooms_to_exclude_from_dummy_event_insertion[room_id] + + async def _rebuild_event_after_third_party_rules( + self, third_party_result: dict, original_event: EventBase + ) -> Tuple[EventBase, EventContext]: + # the third_party_event_rules want to replace the event. + # we do some basic checks, and then return the replacement event and context. + + # Construct a new EventBuilder and validate it, which helps with the + # rest of these checks. + try: + builder = self.event_builder_factory.for_room_version( + original_event.room_version, third_party_result + ) + self.validator.validate_builder(builder) + except SynapseError as e: + raise Exception( + "Third party rules module created an invalid event: " + e.msg, + ) + + immutable_fields = [ + # changing the room is going to break things: we've already checked that the + # room exists, and are holding a concurrency limiter token for that room. + # Also, we might need to use a different room version. + "room_id", + # changing the type or state key might work, but we'd need to check that the + # calling functions aren't making assumptions about them. + "type", + "state_key", + ] + + for k in immutable_fields: + if getattr(builder, k, None) != original_event.get(k): + raise Exception( + "Third party rules module created an invalid event: " + "cannot change field " + k + ) + + # check that the new sender belongs to this HS + if not self.hs.is_mine_id(builder.sender): + raise Exception( + "Third party rules module created an invalid event: " + "invalid sender " + builder.sender + ) + + # copy over the original internal metadata + for k, v in original_event.internal_metadata.get_dict().items(): + setattr(builder.internal_metadata, k, v) + + # the event type hasn't changed, so there's no point in re-calculating the + # auth events. + event = await builder.build( + prev_event_ids=original_event.prev_event_ids(), + auth_event_ids=original_event.auth_event_ids(), + ) + + # we rebuild the event context, to be on the safe side. If nothing else, + # delta_ids might need an update. + context = await self.state.compute_event_context(event) + return event, context |