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- # -*- coding: utf-8 -*-
- # Copyright 2014-2016 OpenMarket Ltd
- # Copyright 2017-2018 New Vector Ltd
- # Copyright 2019 The Matrix.org Foundation C.I.C.
- #
- # 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.
- """Contains handlers for federation events."""
- import itertools
- import logging
- import six
- from six import iteritems, itervalues
- from six.moves import http_client, zip
- from signedjson.key import decode_verify_key_bytes
- from signedjson.sign import verify_signed_json
- from unpaddedbase64 import decode_base64
- from twisted.internet import defer
- from synapse.api.constants import EventTypes, Membership, RejectedReason
- from synapse.api.errors import (
- AuthError,
- CodeMessageException,
- Codes,
- FederationDeniedError,
- FederationError,
- RequestSendFailed,
- StoreError,
- SynapseError,
- )
- from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersions
- from synapse.crypto.event_signing import compute_event_signature
- from synapse.event_auth import auth_types_for_event
- from synapse.events.validator import EventValidator
- from synapse.logging.context import (
- make_deferred_yieldable,
- nested_logging_context,
- preserve_fn,
- run_in_background,
- )
- from synapse.logging.utils import log_function
- from synapse.replication.http.federation import (
- ReplicationCleanRoomRestServlet,
- ReplicationFederationSendEventsRestServlet,
- )
- from synapse.replication.http.membership import ReplicationUserJoinedLeftRoomRestServlet
- from synapse.state import StateResolutionStore, resolve_events_with_store
- from synapse.types import UserID, get_domain_from_id
- from synapse.util import unwrapFirstError
- from synapse.util.async_helpers import Linearizer
- from synapse.util.distributor import user_joined_room
- from synapse.util.retryutils import NotRetryingDestination
- from synapse.visibility import filter_events_for_server
- from ._base import BaseHandler
- logger = logging.getLogger(__name__)
- def shortstr(iterable, maxitems=5):
- """If iterable has maxitems or fewer, return the stringification of a list
- containing those items.
- Otherwise, return the stringification of a a list with the first maxitems items,
- followed by "...".
- Args:
- iterable (Iterable): iterable to truncate
- maxitems (int): number of items to return before truncating
- Returns:
- unicode
- """
- items = list(itertools.islice(iterable, maxitems + 1))
- if len(items) <= maxitems:
- return str(items)
- return "[" + ", ".join(repr(r) for r in items[:maxitems]) + ", ...]"
- class FederationHandler(BaseHandler):
- """Handles events that originated from federation.
- Responsible for:
- a) handling received Pdus before handing them on as Events to the rest
- of the home server (including auth and state conflict resoultion)
- b) converting events that were produced by local clients that may need
- to be sent to remote home servers.
- c) doing the necessary dances to invite remote users and join remote
- rooms.
- """
- def __init__(self, hs):
- super(FederationHandler, self).__init__(hs)
- self.hs = hs
- self.store = hs.get_datastore()
- self.federation_client = hs.get_federation_client()
- self.state_handler = hs.get_state_handler()
- self.server_name = hs.hostname
- self.keyring = hs.get_keyring()
- self.action_generator = hs.get_action_generator()
- self.is_mine_id = hs.is_mine_id
- self.pusher_pool = hs.get_pusherpool()
- self.spam_checker = hs.get_spam_checker()
- self.event_creation_handler = hs.get_event_creation_handler()
- self._server_notices_mxid = hs.config.server_notices_mxid
- self.config = hs.config
- self.http_client = hs.get_simple_http_client()
- self._send_events_to_master = ReplicationFederationSendEventsRestServlet.make_client(
- hs
- )
- self._notify_user_membership_change = ReplicationUserJoinedLeftRoomRestServlet.make_client(
- hs
- )
- self._clean_room_for_join_client = ReplicationCleanRoomRestServlet.make_client(
- hs
- )
- # When joining a room we need to queue any events for that room up
- self.room_queues = {}
- self._room_pdu_linearizer = Linearizer("fed_room_pdu")
- self.third_party_event_rules = hs.get_third_party_event_rules()
- @defer.inlineCallbacks
- def on_receive_pdu(self, origin, pdu, sent_to_us_directly=False):
- """ Process a PDU received via a federation /send/ transaction, or
- via backfill of missing prev_events
- Args:
- origin (str): server which initiated the /send/ transaction. Will
- be used to fetch missing events or state.
- pdu (FrozenEvent): received PDU
- sent_to_us_directly (bool): True if this event was pushed to us; False if
- we pulled it as the result of a missing prev_event.
- Returns (Deferred): completes with None
- """
- room_id = pdu.room_id
- event_id = pdu.event_id
- logger.info("[%s %s] handling received PDU: %s", room_id, event_id, pdu)
- # We reprocess pdus when we have seen them only as outliers
- existing = yield self.store.get_event(
- event_id, allow_none=True, allow_rejected=True
- )
- # FIXME: Currently we fetch an event again when we already have it
- # if it has been marked as an outlier.
- already_seen = existing and (
- not existing.internal_metadata.is_outlier()
- or pdu.internal_metadata.is_outlier()
- )
- if already_seen:
- logger.debug("[%s %s]: Already seen pdu", room_id, event_id)
- return
- # do some initial sanity-checking of the event. In particular, make
- # sure it doesn't have hundreds of prev_events or auth_events, which
- # could cause a huge state resolution or cascade of event fetches.
- try:
- self._sanity_check_event(pdu)
- except SynapseError as err:
- logger.warn(
- "[%s %s] Received event failed sanity checks", room_id, event_id
- )
- raise FederationError("ERROR", err.code, err.msg, affected=pdu.event_id)
- # If we are currently in the process of joining this room, then we
- # queue up events for later processing.
- if room_id in self.room_queues:
- logger.info(
- "[%s %s] Queuing PDU from %s for now: join in progress",
- room_id,
- event_id,
- origin,
- )
- self.room_queues[room_id].append((pdu, origin))
- return
- # If we're not in the room just ditch the event entirely. This is
- # probably an old server that has come back and thinks we're still in
- # the room (or we've been rejoined to the room by a state reset).
- #
- # Note that if we were never in the room then we would have already
- # dropped the event, since we wouldn't know the room version.
- is_in_room = yield self.auth.check_host_in_room(room_id, self.server_name)
- if not is_in_room:
- logger.info(
- "[%s %s] Ignoring PDU from %s as we're not in the room",
- room_id,
- event_id,
- origin,
- )
- return None
- state = None
- auth_chain = []
- # Get missing pdus if necessary.
- if not pdu.internal_metadata.is_outlier():
- # We only backfill backwards to the min depth.
- min_depth = yield self.get_min_depth_for_context(pdu.room_id)
- logger.debug("[%s %s] min_depth: %d", room_id, event_id, min_depth)
- prevs = set(pdu.prev_event_ids())
- seen = yield self.store.have_seen_events(prevs)
- if min_depth and pdu.depth < min_depth:
- # This is so that we don't notify the user about this
- # message, to work around the fact that some events will
- # reference really really old events we really don't want to
- # send to the clients.
- pdu.internal_metadata.outlier = True
- elif min_depth and pdu.depth > min_depth:
- missing_prevs = prevs - seen
- if sent_to_us_directly and missing_prevs:
- # If we're missing stuff, ensure we only fetch stuff one
- # at a time.
- logger.info(
- "[%s %s] Acquiring room lock to fetch %d missing prev_events: %s",
- room_id,
- event_id,
- len(missing_prevs),
- shortstr(missing_prevs),
- )
- with (yield self._room_pdu_linearizer.queue(pdu.room_id)):
- logger.info(
- "[%s %s] Acquired room lock to fetch %d missing prev_events",
- room_id,
- event_id,
- len(missing_prevs),
- )
- yield self._get_missing_events_for_pdu(
- origin, pdu, prevs, min_depth
- )
- # Update the set of things we've seen after trying to
- # fetch the missing stuff
- seen = yield self.store.have_seen_events(prevs)
- if not prevs - seen:
- logger.info(
- "[%s %s] Found all missing prev_events",
- room_id,
- event_id,
- )
- elif missing_prevs:
- logger.info(
- "[%s %s] Not recursively fetching %d missing prev_events: %s",
- room_id,
- event_id,
- len(missing_prevs),
- shortstr(missing_prevs),
- )
- if prevs - seen:
- # We've still not been able to get all of the prev_events for this event.
- #
- # In this case, we need to fall back to asking another server in the
- # federation for the state at this event. That's ok provided we then
- # resolve the state against other bits of the DAG before using it (which
- # will ensure that you can't just take over a room by sending an event,
- # withholding its prev_events, and declaring yourself to be an admin in
- # the subsequent state request).
- #
- # Now, if we're pulling this event as a missing prev_event, then clearly
- # this event is not going to become the only forward-extremity and we are
- # guaranteed to resolve its state against our existing forward
- # extremities, so that should be fine.
- #
- # On the other hand, if this event was pushed to us, it is possible for
- # it to become the only forward-extremity in the room, and we would then
- # trust its state to be the state for the whole room. This is very bad.
- # Further, if the event was pushed to us, there is no excuse for us not to
- # have all the prev_events. We therefore reject any such events.
- #
- # XXX this really feels like it could/should be merged with the above,
- # but there is an interaction with min_depth that I'm not really
- # following.
- if sent_to_us_directly:
- logger.warn(
- "[%s %s] Rejecting: failed to fetch %d prev events: %s",
- room_id,
- event_id,
- len(prevs - seen),
- shortstr(prevs - seen),
- )
- raise FederationError(
- "ERROR",
- 403,
- (
- "Your server isn't divulging details about prev_events "
- "referenced in this event."
- ),
- affected=pdu.event_id,
- )
- # Calculate the state after each of the previous events, and
- # resolve them to find the correct state at the current event.
- auth_chains = set()
- event_map = {event_id: pdu}
- try:
- # Get the state of the events we know about
- ours = yield self.store.get_state_groups_ids(room_id, seen)
- # state_maps is a list of mappings from (type, state_key) to event_id
- # type: list[dict[tuple[str, str], str]]
- state_maps = list(ours.values())
- # we don't need this any more, let's delete it.
- del ours
- # Ask the remote server for the states we don't
- # know about
- for p in prevs - seen:
- logger.info(
- "[%s %s] Requesting state at missing prev_event %s",
- room_id,
- event_id,
- p,
- )
- room_version = yield self.store.get_room_version(room_id)
- with nested_logging_context(p):
- # note that if any of the missing prevs share missing state or
- # auth events, the requests to fetch those events are deduped
- # by the get_pdu_cache in federation_client.
- remote_state, got_auth_chain = (
- yield self.federation_client.get_state_for_room(
- origin, room_id, p
- )
- )
- # we want the state *after* p; get_state_for_room returns the
- # state *before* p.
- remote_event = yield self.federation_client.get_pdu(
- [origin], p, room_version, outlier=True
- )
- if remote_event is None:
- raise Exception(
- "Unable to get missing prev_event %s" % (p,)
- )
- if remote_event.is_state():
- remote_state.append(remote_event)
- # XXX hrm I'm not convinced that duplicate events will compare
- # for equality, so I'm not sure this does what the author
- # hoped.
- auth_chains.update(got_auth_chain)
- remote_state_map = {
- (x.type, x.state_key): x.event_id for x in remote_state
- }
- state_maps.append(remote_state_map)
- for x in remote_state:
- event_map[x.event_id] = x
- state_map = yield resolve_events_with_store(
- room_version,
- state_maps,
- event_map,
- state_res_store=StateResolutionStore(self.store),
- )
- # We need to give _process_received_pdu the actual state events
- # rather than event ids, so generate that now.
- # First though we need to fetch all the events that are in
- # state_map, so we can build up the state below.
- evs = yield self.store.get_events(
- list(state_map.values()),
- get_prev_content=False,
- check_redacted=False,
- )
- event_map.update(evs)
- state = [event_map[e] for e in six.itervalues(state_map)]
- auth_chain = list(auth_chains)
- except Exception:
- logger.warn(
- "[%s %s] Error attempting to resolve state at missing "
- "prev_events",
- room_id,
- event_id,
- exc_info=True,
- )
- raise FederationError(
- "ERROR",
- 403,
- "We can't get valid state history.",
- affected=event_id,
- )
- yield self._process_received_pdu(
- origin, pdu, state=state, auth_chain=auth_chain
- )
- @defer.inlineCallbacks
- def _get_missing_events_for_pdu(self, origin, pdu, prevs, min_depth):
- """
- Args:
- origin (str): Origin of the pdu. Will be called to get the missing events
- pdu: received pdu
- prevs (set(str)): List of event ids which we are missing
- min_depth (int): Minimum depth of events to return.
- """
- room_id = pdu.room_id
- event_id = pdu.event_id
- seen = yield self.store.have_seen_events(prevs)
- if not prevs - seen:
- return
- latest = yield self.store.get_latest_event_ids_in_room(room_id)
- # We add the prev events that we have seen to the latest
- # list to ensure the remote server doesn't give them to us
- latest = set(latest)
- latest |= seen
- logger.info(
- "[%s %s]: Requesting missing events between %s and %s",
- room_id,
- event_id,
- shortstr(latest),
- event_id,
- )
- # XXX: we set timeout to 10s to help workaround
- # https://github.com/matrix-org/synapse/issues/1733.
- # The reason is to avoid holding the linearizer lock
- # whilst processing inbound /send transactions, causing
- # FDs to stack up and block other inbound transactions
- # which empirically can currently take up to 30 minutes.
- #
- # N.B. this explicitly disables retry attempts.
- #
- # N.B. this also increases our chances of falling back to
- # fetching fresh state for the room if the missing event
- # can't be found, which slightly reduces our security.
- # it may also increase our DAG extremity count for the room,
- # causing additional state resolution? See #1760.
- # However, fetching state doesn't hold the linearizer lock
- # apparently.
- #
- # see https://github.com/matrix-org/synapse/pull/1744
- #
- # ----
- #
- # Update richvdh 2018/09/18: There are a number of problems with timing this
- # request out agressively on the client side:
- #
- # - it plays badly with the server-side rate-limiter, which starts tarpitting you
- # if you send too many requests at once, so you end up with the server carefully
- # working through the backlog of your requests, which you have already timed
- # out.
- #
- # - for this request in particular, we now (as of
- # https://github.com/matrix-org/synapse/pull/3456) reject any PDUs where the
- # server can't produce a plausible-looking set of prev_events - so we becone
- # much more likely to reject the event.
- #
- # - contrary to what it says above, we do *not* fall back to fetching fresh state
- # for the room if get_missing_events times out. Rather, we give up processing
- # the PDU whose prevs we are missing, which then makes it much more likely that
- # we'll end up back here for the *next* PDU in the list, which exacerbates the
- # problem.
- #
- # - the agressive 10s timeout was introduced to deal with incoming federation
- # requests taking 8 hours to process. It's not entirely clear why that was going
- # on; certainly there were other issues causing traffic storms which are now
- # resolved, and I think in any case we may be more sensible about our locking
- # now. We're *certainly* more sensible about our logging.
- #
- # All that said: Let's try increasing the timout to 60s and see what happens.
- try:
- missing_events = yield self.federation_client.get_missing_events(
- origin,
- room_id,
- earliest_events_ids=list(latest),
- latest_events=[pdu],
- limit=10,
- min_depth=min_depth,
- timeout=60000,
- )
- except RequestSendFailed as e:
- # We failed to get the missing events, but since we need to handle
- # the case of `get_missing_events` not returning the necessary
- # events anyway, it is safe to simply log the error and continue.
- logger.warn("[%s %s]: Failed to get prev_events: %s", room_id, event_id, e)
- return
- logger.info(
- "[%s %s]: Got %d prev_events: %s",
- room_id,
- event_id,
- len(missing_events),
- shortstr(missing_events),
- )
- # We want to sort these by depth so we process them and
- # tell clients about them in order.
- missing_events.sort(key=lambda x: x.depth)
- for ev in missing_events:
- logger.info(
- "[%s %s] Handling received prev_event %s",
- room_id,
- event_id,
- ev.event_id,
- )
- with nested_logging_context(ev.event_id):
- try:
- yield self.on_receive_pdu(origin, ev, sent_to_us_directly=False)
- except FederationError as e:
- if e.code == 403:
- logger.warn(
- "[%s %s] Received prev_event %s failed history check.",
- room_id,
- event_id,
- ev.event_id,
- )
- else:
- raise
- @defer.inlineCallbacks
- def _process_received_pdu(self, origin, event, state, auth_chain):
- """ Called when we have a new pdu. We need to do auth checks and put it
- through the StateHandler.
- """
- room_id = event.room_id
- event_id = event.event_id
- logger.debug("[%s %s] Processing event: %s", room_id, event_id, event)
- event_ids = set()
- if state:
- event_ids |= {e.event_id for e in state}
- if auth_chain:
- event_ids |= {e.event_id for e in auth_chain}
- seen_ids = yield self.store.have_seen_events(event_ids)
- if state and auth_chain is not None:
- # If we have any state or auth_chain given to us by the replication
- # layer, then we should handle them (if we haven't before.)
- event_infos = []
- for e in itertools.chain(auth_chain, state):
- if e.event_id in seen_ids:
- continue
- e.internal_metadata.outlier = True
- auth_ids = e.auth_event_ids()
- auth = {
- (e.type, e.state_key): e
- for e in auth_chain
- if e.event_id in auth_ids or e.type == EventTypes.Create
- }
- event_infos.append({"event": e, "auth_events": auth})
- seen_ids.add(e.event_id)
- logger.info(
- "[%s %s] persisting newly-received auth/state events %s",
- room_id,
- event_id,
- [e["event"].event_id for e in event_infos],
- )
- yield self._handle_new_events(origin, event_infos)
- try:
- context = yield self._handle_new_event(origin, event, state=state)
- except AuthError as e:
- raise FederationError("ERROR", e.code, e.msg, affected=event.event_id)
- room = yield self.store.get_room(room_id)
- if not room:
- try:
- yield self.store.store_room(
- room_id=room_id, room_creator_user_id="", is_public=False
- )
- except StoreError:
- logger.exception("Failed to store room.")
- if event.type == EventTypes.Member:
- if event.membership == Membership.JOIN:
- # Only fire user_joined_room if the user has acutally
- # joined the room. Don't bother if the user is just
- # changing their profile info.
- newly_joined = True
- prev_state_ids = yield context.get_prev_state_ids(self.store)
- prev_state_id = prev_state_ids.get((event.type, event.state_key))
- if prev_state_id:
- prev_state = yield self.store.get_event(
- prev_state_id, allow_none=True
- )
- if prev_state and prev_state.membership == Membership.JOIN:
- newly_joined = False
- if newly_joined:
- user = UserID.from_string(event.state_key)
- yield self.user_joined_room(user, room_id)
- @log_function
- @defer.inlineCallbacks
- def backfill(self, dest, room_id, limit, extremities):
- """ Trigger a backfill request to `dest` for the given `room_id`
- This will attempt to get more events from the remote. If the other side
- has no new events to offer, this will return an empty list.
- As the events are received, we check their signatures, and also do some
- sanity-checking on them. If any of the backfilled events are invalid,
- this method throws a SynapseError.
- TODO: make this more useful to distinguish failures of the remote
- server from invalid events (there is probably no point in trying to
- re-fetch invalid events from every other HS in the room.)
- """
- if dest == self.server_name:
- raise SynapseError(400, "Can't backfill from self.")
- room_version = yield self.store.get_room_version(room_id)
- events = yield self.federation_client.backfill(
- dest, room_id, limit=limit, extremities=extremities
- )
- # ideally we'd sanity check the events here for excess prev_events etc,
- # but it's hard to reject events at this point without completely
- # breaking backfill in the same way that it is currently broken by
- # events whose signature we cannot verify (#3121).
- #
- # So for now we accept the events anyway. #3124 tracks this.
- #
- # for ev in events:
- # self._sanity_check_event(ev)
- # Don't bother processing events we already have.
- seen_events = yield self.store.have_events_in_timeline(
- set(e.event_id for e in events)
- )
- events = [e for e in events if e.event_id not in seen_events]
- if not events:
- return []
- event_map = {e.event_id: e for e in events}
- event_ids = set(e.event_id for e in events)
- edges = [ev.event_id for ev in events if set(ev.prev_event_ids()) - event_ids]
- logger.info("backfill: Got %d events with %d edges", len(events), len(edges))
- # For each edge get the current state.
- auth_events = {}
- state_events = {}
- events_to_state = {}
- for e_id in edges:
- state, auth = yield self.federation_client.get_state_for_room(
- destination=dest, room_id=room_id, event_id=e_id
- )
- auth_events.update({a.event_id: a for a in auth})
- auth_events.update({s.event_id: s for s in state})
- state_events.update({s.event_id: s for s in state})
- events_to_state[e_id] = state
- required_auth = set(
- a_id
- for event in events
- + list(state_events.values())
- + list(auth_events.values())
- for a_id in event.auth_event_ids()
- )
- auth_events.update(
- {e_id: event_map[e_id] for e_id in required_auth if e_id in event_map}
- )
- missing_auth = required_auth - set(auth_events)
- failed_to_fetch = set()
- # Try and fetch any missing auth events from both DB and remote servers.
- # We repeatedly do this until we stop finding new auth events.
- while missing_auth - failed_to_fetch:
- logger.info("Missing auth for backfill: %r", missing_auth)
- ret_events = yield self.store.get_events(missing_auth - failed_to_fetch)
- auth_events.update(ret_events)
- required_auth.update(
- a_id for event in ret_events.values() for a_id in event.auth_event_ids()
- )
- missing_auth = required_auth - set(auth_events)
- if missing_auth - failed_to_fetch:
- logger.info(
- "Fetching missing auth for backfill: %r",
- missing_auth - failed_to_fetch,
- )
- results = yield make_deferred_yieldable(
- defer.gatherResults(
- [
- run_in_background(
- self.federation_client.get_pdu,
- [dest],
- event_id,
- room_version=room_version,
- outlier=True,
- timeout=10000,
- )
- for event_id in missing_auth - failed_to_fetch
- ],
- consumeErrors=True,
- )
- ).addErrback(unwrapFirstError)
- auth_events.update({a.event_id: a for a in results if a})
- required_auth.update(
- a_id
- for event in results
- if event
- for a_id in event.auth_event_ids()
- )
- missing_auth = required_auth - set(auth_events)
- failed_to_fetch = missing_auth - set(auth_events)
- seen_events = yield self.store.have_seen_events(
- set(auth_events.keys()) | set(state_events.keys())
- )
- # We now have a chunk of events plus associated state and auth chain to
- # persist. We do the persistence in two steps:
- # 1. Auth events and state get persisted as outliers, plus the
- # backward extremities get persisted (as non-outliers).
- # 2. The rest of the events in the chunk get persisted one by one, as
- # each one depends on the previous event for its state.
- #
- # The important thing is that events in the chunk get persisted as
- # non-outliers, including when those events are also in the state or
- # auth chain. Caution must therefore be taken to ensure that they are
- # not accidentally marked as outliers.
- # Step 1a: persist auth events that *don't* appear in the chunk
- ev_infos = []
- for a in auth_events.values():
- # We only want to persist auth events as outliers that we haven't
- # seen and aren't about to persist as part of the backfilled chunk.
- if a.event_id in seen_events or a.event_id in event_map:
- continue
- a.internal_metadata.outlier = True
- ev_infos.append(
- {
- "event": a,
- "auth_events": {
- (
- auth_events[a_id].type,
- auth_events[a_id].state_key,
- ): auth_events[a_id]
- for a_id in a.auth_event_ids()
- if a_id in auth_events
- },
- }
- )
- # Step 1b: persist the events in the chunk we fetched state for (i.e.
- # the backwards extremities) as non-outliers.
- for e_id in events_to_state:
- # For paranoia we ensure that these events are marked as
- # non-outliers
- ev = event_map[e_id]
- assert not ev.internal_metadata.is_outlier()
- ev_infos.append(
- {
- "event": ev,
- "state": events_to_state[e_id],
- "auth_events": {
- (
- auth_events[a_id].type,
- auth_events[a_id].state_key,
- ): auth_events[a_id]
- for a_id in ev.auth_event_ids()
- if a_id in auth_events
- },
- }
- )
- yield self._handle_new_events(dest, ev_infos, backfilled=True)
- # Step 2: Persist the rest of the events in the chunk one by one
- events.sort(key=lambda e: e.depth)
- for event in events:
- if event in events_to_state:
- continue
- # For paranoia we ensure that these events are marked as
- # non-outliers
- assert not event.internal_metadata.is_outlier()
- # We store these one at a time since each event depends on the
- # previous to work out the state.
- # TODO: We can probably do something more clever here.
- yield self._handle_new_event(dest, event, backfilled=True)
- return events
- @defer.inlineCallbacks
- def maybe_backfill(self, room_id, current_depth):
- """Checks the database to see if we should backfill before paginating,
- and if so do.
- """
- extremities = yield self.store.get_oldest_events_with_depth_in_room(room_id)
- if not extremities:
- logger.debug("Not backfilling as no extremeties found.")
- return
- # We only want to paginate if we can actually see the events we'll get,
- # as otherwise we'll just spend a lot of resources to get redacted
- # events.
- #
- # We do this by filtering all the backwards extremities and seeing if
- # any remain. Given we don't have the extremity events themselves, we
- # need to actually check the events that reference them.
- #
- # *Note*: the spec wants us to keep backfilling until we reach the start
- # of the room in case we are allowed to see some of the history. However
- # in practice that causes more issues than its worth, as a) its
- # relatively rare for there to be any visible history and b) even when
- # there is its often sufficiently long ago that clients would stop
- # attempting to paginate before backfill reached the visible history.
- #
- # TODO: If we do do a backfill then we should filter the backwards
- # extremities to only include those that point to visible portions of
- # history.
- #
- # TODO: Correctly handle the case where we are allowed to see the
- # forward event but not the backward extremity, e.g. in the case of
- # initial join of the server where we are allowed to see the join
- # event but not anything before it. This would require looking at the
- # state *before* the event, ignoring the special casing certain event
- # types have.
- forward_events = yield self.store.get_successor_events(list(extremities))
- extremities_events = yield self.store.get_events(
- forward_events, check_redacted=False, get_prev_content=False
- )
- # We set `check_history_visibility_only` as we might otherwise get false
- # positives from users having been erased.
- filtered_extremities = yield filter_events_for_server(
- self.store,
- self.server_name,
- list(extremities_events.values()),
- redact=False,
- check_history_visibility_only=True,
- )
- if not filtered_extremities:
- return False
- # Check if we reached a point where we should start backfilling.
- sorted_extremeties_tuple = sorted(extremities.items(), key=lambda e: -int(e[1]))
- max_depth = sorted_extremeties_tuple[0][1]
- # We don't want to specify too many extremities as it causes the backfill
- # request URI to be too long.
- extremities = dict(sorted_extremeties_tuple[:5])
- if current_depth > max_depth:
- logger.debug(
- "Not backfilling as we don't need to. %d < %d", max_depth, current_depth
- )
- return
- # Now we need to decide which hosts to hit first.
- # First we try hosts that are already in the room
- # TODO: HEURISTIC ALERT.
- curr_state = yield self.state_handler.get_current_state(room_id)
- def get_domains_from_state(state):
- """Get joined domains from state
- Args:
- state (dict[tuple, FrozenEvent]): State map from type/state
- key to event.
- Returns:
- list[tuple[str, int]]: Returns a list of servers with the
- lowest depth of their joins. Sorted by lowest depth first.
- """
- joined_users = [
- (state_key, int(event.depth))
- for (e_type, state_key), event in iteritems(state)
- if e_type == EventTypes.Member and event.membership == Membership.JOIN
- ]
- joined_domains = {}
- for u, d in joined_users:
- try:
- dom = get_domain_from_id(u)
- old_d = joined_domains.get(dom)
- if old_d:
- joined_domains[dom] = min(d, old_d)
- else:
- joined_domains[dom] = d
- except Exception:
- pass
- return sorted(joined_domains.items(), key=lambda d: d[1])
- curr_domains = get_domains_from_state(curr_state)
- likely_domains = [
- domain for domain, depth in curr_domains if domain != self.server_name
- ]
- @defer.inlineCallbacks
- def try_backfill(domains):
- # TODO: Should we try multiple of these at a time?
- for dom in domains:
- try:
- yield self.backfill(
- dom, room_id, limit=100, extremities=extremities
- )
- # If this succeeded then we probably already have the
- # appropriate stuff.
- # TODO: We can probably do something more intelligent here.
- return True
- except SynapseError as e:
- logger.info("Failed to backfill from %s because %s", dom, e)
- continue
- except CodeMessageException as e:
- if 400 <= e.code < 500:
- raise
- logger.info("Failed to backfill from %s because %s", dom, e)
- continue
- except NotRetryingDestination as e:
- logger.info(str(e))
- continue
- except FederationDeniedError as e:
- logger.info(e)
- continue
- except Exception as e:
- logger.exception("Failed to backfill from %s because %s", dom, e)
- continue
- return False
- success = yield try_backfill(likely_domains)
- if success:
- return True
- # Huh, well *those* domains didn't work out. Lets try some domains
- # from the time.
- tried_domains = set(likely_domains)
- tried_domains.add(self.server_name)
- event_ids = list(extremities.keys())
- logger.debug("calling resolve_state_groups in _maybe_backfill")
- resolve = preserve_fn(self.state_handler.resolve_state_groups_for_events)
- states = yield make_deferred_yieldable(
- defer.gatherResults(
- [resolve(room_id, [e]) for e in event_ids], consumeErrors=True
- )
- )
- # dict[str, dict[tuple, str]], a map from event_id to state map of
- # event_ids.
- states = dict(zip(event_ids, [s.state for s in states]))
- state_map = yield self.store.get_events(
- [e_id for ids in itervalues(states) for e_id in itervalues(ids)],
- get_prev_content=False,
- )
- states = {
- key: {
- k: state_map[e_id]
- for k, e_id in iteritems(state_dict)
- if e_id in state_map
- }
- for key, state_dict in iteritems(states)
- }
- for e_id, _ in sorted_extremeties_tuple:
- likely_domains = get_domains_from_state(states[e_id])
- success = yield try_backfill(
- [dom for dom, _ in likely_domains if dom not in tried_domains]
- )
- if success:
- return True
- tried_domains.update(dom for dom, _ in likely_domains)
- return False
- def _sanity_check_event(self, ev):
- """
- Do some early sanity checks of a received event
- In particular, checks it doesn't have an excessive number of
- prev_events or auth_events, which could cause a huge state resolution
- or cascade of event fetches.
- Args:
- ev (synapse.events.EventBase): event to be checked
- Returns: None
- Raises:
- SynapseError if the event does not pass muster
- """
- if len(ev.prev_event_ids()) > 20:
- logger.warn(
- "Rejecting event %s which has %i prev_events",
- ev.event_id,
- len(ev.prev_event_ids()),
- )
- raise SynapseError(http_client.BAD_REQUEST, "Too many prev_events")
- if len(ev.auth_event_ids()) > 10:
- logger.warn(
- "Rejecting event %s which has %i auth_events",
- ev.event_id,
- len(ev.auth_event_ids()),
- )
- raise SynapseError(http_client.BAD_REQUEST, "Too many auth_events")
- @defer.inlineCallbacks
- def send_invite(self, target_host, event):
- """ Sends the invite to the remote server for signing.
- Invites must be signed by the invitee's server before distribution.
- """
- pdu = yield self.federation_client.send_invite(
- destination=target_host,
- room_id=event.room_id,
- event_id=event.event_id,
- pdu=event,
- )
- return pdu
- @defer.inlineCallbacks
- def on_event_auth(self, event_id):
- event = yield self.store.get_event(event_id)
- auth = yield self.store.get_auth_chain(
- [auth_id for auth_id in event.auth_event_ids()], include_given=True
- )
- return [e for e in auth]
- @log_function
- @defer.inlineCallbacks
- def do_invite_join(self, target_hosts, room_id, joinee, content):
- """ Attempts to join the `joinee` to the room `room_id` via the
- server `target_host`.
- This first triggers a /make_join/ request that returns a partial
- event that we can fill out and sign. This is then sent to the
- remote server via /send_join/ which responds with the state at that
- event and the auth_chains.
- We suspend processing of any received events from this room until we
- have finished processing the join.
- """
- logger.debug("Joining %s to %s", joinee, room_id)
- origin, event, event_format_version = yield self._make_and_verify_event(
- target_hosts,
- room_id,
- joinee,
- "join",
- content,
- params={"ver": KNOWN_ROOM_VERSIONS},
- )
- # This shouldn't happen, because the RoomMemberHandler has a
- # linearizer lock which only allows one operation per user per room
- # at a time - so this is just paranoia.
- assert room_id not in self.room_queues
- self.room_queues[room_id] = []
- yield self._clean_room_for_join(room_id)
- handled_events = set()
- try:
- # Try the host we successfully got a response to /make_join/
- # request first.
- try:
- target_hosts.remove(origin)
- target_hosts.insert(0, origin)
- except ValueError:
- pass
- ret = yield self.federation_client.send_join(
- target_hosts, event, event_format_version
- )
- origin = ret["origin"]
- state = ret["state"]
- auth_chain = ret["auth_chain"]
- auth_chain.sort(key=lambda e: e.depth)
- handled_events.update([s.event_id for s in state])
- handled_events.update([a.event_id for a in auth_chain])
- handled_events.add(event.event_id)
- logger.debug("do_invite_join auth_chain: %s", auth_chain)
- logger.debug("do_invite_join state: %s", state)
- logger.debug("do_invite_join event: %s", event)
- try:
- yield self.store.store_room(
- room_id=room_id, room_creator_user_id="", is_public=False
- )
- except Exception:
- # FIXME
- pass
- yield self._persist_auth_tree(origin, auth_chain, state, event)
- logger.debug("Finished joining %s to %s", joinee, room_id)
- finally:
- room_queue = self.room_queues[room_id]
- del self.room_queues[room_id]
- # we don't need to wait for the queued events to be processed -
- # it's just a best-effort thing at this point. We do want to do
- # them roughly in order, though, otherwise we'll end up making
- # lots of requests for missing prev_events which we do actually
- # have. Hence we fire off the deferred, but don't wait for it.
- run_in_background(self._handle_queued_pdus, room_queue)
- return True
- @defer.inlineCallbacks
- def _handle_queued_pdus(self, room_queue):
- """Process PDUs which got queued up while we were busy send_joining.
- Args:
- room_queue (list[FrozenEvent, str]): list of PDUs to be processed
- and the servers that sent them
- """
- for p, origin in room_queue:
- try:
- logger.info(
- "Processing queued PDU %s which was received "
- "while we were joining %s",
- p.event_id,
- p.room_id,
- )
- with nested_logging_context(p.event_id):
- yield self.on_receive_pdu(origin, p, sent_to_us_directly=True)
- except Exception as e:
- logger.warn(
- "Error handling queued PDU %s from %s: %s", p.event_id, origin, e
- )
- @defer.inlineCallbacks
- @log_function
- def on_make_join_request(self, room_id, user_id):
- """ We've received a /make_join/ request, so we create a partial
- join event for the room and return that. We do *not* persist or
- process it until the other server has signed it and sent it back.
- """
- event_content = {"membership": Membership.JOIN}
- room_version = yield self.store.get_room_version(room_id)
- builder = self.event_builder_factory.new(
- room_version,
- {
- "type": EventTypes.Member,
- "content": event_content,
- "room_id": room_id,
- "sender": user_id,
- "state_key": user_id,
- },
- )
- try:
- event, context = yield self.event_creation_handler.create_new_client_event(
- builder=builder
- )
- except AuthError as e:
- logger.warn("Failed to create join %r because %s", event, e)
- raise e
- event_allowed = yield self.third_party_event_rules.check_event_allowed(
- event, context
- )
- if not event_allowed:
- logger.info("Creation of join %s forbidden by third-party rules", event)
- raise SynapseError(
- 403, "This event is not allowed in this context", Codes.FORBIDDEN
- )
- # The remote hasn't signed it yet, obviously. We'll do the full checks
- # when we get the event back in `on_send_join_request`
- yield self.auth.check_from_context(
- room_version, event, context, do_sig_check=False
- )
- return event
- @defer.inlineCallbacks
- @log_function
- def on_send_join_request(self, origin, pdu):
- """ We have received a join event for a room. Fully process it and
- respond with the current state and auth chains.
- """
- event = pdu
- logger.debug(
- "on_send_join_request: Got event: %s, signatures: %s",
- event.event_id,
- event.signatures,
- )
- event.internal_metadata.outlier = False
- # Send this event on behalf of the origin server.
- #
- # The reasons we have the destination server rather than the origin
- # server send it are slightly mysterious: the origin server should have
- # all the neccessary state once it gets the response to the send_join,
- # so it could send the event itself if it wanted to. It may be that
- # doing it this way reduces failure modes, or avoids certain attacks
- # where a new server selectively tells a subset of the federation that
- # it has joined.
- #
- # The fact is that, as of the current writing, Synapse doesn't send out
- # the join event over federation after joining, and changing it now
- # would introduce the danger of backwards-compatibility problems.
- event.internal_metadata.send_on_behalf_of = origin
- context = yield self._handle_new_event(origin, event)
- event_allowed = yield self.third_party_event_rules.check_event_allowed(
- event, context
- )
- if not event_allowed:
- logger.info("Sending of join %s forbidden by third-party rules", event)
- raise SynapseError(
- 403, "This event is not allowed in this context", Codes.FORBIDDEN
- )
- logger.debug(
- "on_send_join_request: After _handle_new_event: %s, sigs: %s",
- event.event_id,
- event.signatures,
- )
- if event.type == EventTypes.Member:
- if event.content["membership"] == Membership.JOIN:
- user = UserID.from_string(event.state_key)
- yield self.user_joined_room(user, event.room_id)
- prev_state_ids = yield context.get_prev_state_ids(self.store)
- state_ids = list(prev_state_ids.values())
- auth_chain = yield self.store.get_auth_chain(state_ids)
- state = yield self.store.get_events(list(prev_state_ids.values()))
- return {"state": list(state.values()), "auth_chain": auth_chain}
- @defer.inlineCallbacks
- def on_invite_request(self, origin, pdu):
- """ We've got an invite event. Process and persist it. Sign it.
- Respond with the now signed event.
- """
- event = pdu
- if event.state_key is None:
- raise SynapseError(400, "The invite event did not have a state key")
- is_blocked = yield self.store.is_room_blocked(event.room_id)
- if is_blocked:
- raise SynapseError(403, "This room has been blocked on this server")
- if self.hs.config.block_non_admin_invites:
- raise SynapseError(403, "This server does not accept room invites")
- if not self.spam_checker.user_may_invite(
- event.sender, event.state_key, event.room_id
- ):
- raise SynapseError(
- 403, "This user is not permitted to send invites to this server/user"
- )
- membership = event.content.get("membership")
- if event.type != EventTypes.Member or membership != Membership.INVITE:
- raise SynapseError(400, "The event was not an m.room.member invite event")
- sender_domain = get_domain_from_id(event.sender)
- if sender_domain != origin:
- raise SynapseError(
- 400, "The invite event was not from the server sending it"
- )
- if not self.is_mine_id(event.state_key):
- raise SynapseError(400, "The invite event must be for this server")
- # block any attempts to invite the server notices mxid
- if event.state_key == self._server_notices_mxid:
- raise SynapseError(http_client.FORBIDDEN, "Cannot invite this user")
- event.internal_metadata.outlier = True
- event.internal_metadata.out_of_band_membership = True
- event.signatures.update(
- compute_event_signature(
- event.get_pdu_json(), self.hs.hostname, self.hs.config.signing_key[0]
- )
- )
- context = yield self.state_handler.compute_event_context(event)
- yield self.persist_events_and_notify([(event, context)])
- return event
- @defer.inlineCallbacks
- def do_remotely_reject_invite(self, target_hosts, room_id, user_id):
- origin, event, event_format_version = yield self._make_and_verify_event(
- target_hosts, room_id, user_id, "leave"
- )
- # Mark as outlier as we don't have any state for this event; we're not
- # even in the room.
- event.internal_metadata.outlier = True
- event.internal_metadata.out_of_band_membership = True
- # Try the host that we succesfully called /make_leave/ on first for
- # the /send_leave/ request.
- try:
- target_hosts.remove(origin)
- target_hosts.insert(0, origin)
- except ValueError:
- pass
- yield self.federation_client.send_leave(target_hosts, event)
- context = yield self.state_handler.compute_event_context(event)
- yield self.persist_events_and_notify([(event, context)])
- return event
- @defer.inlineCallbacks
- def _make_and_verify_event(
- self, target_hosts, room_id, user_id, membership, content={}, params=None
- ):
- origin, event, format_ver = yield self.federation_client.make_membership_event(
- target_hosts, room_id, user_id, membership, content, params=params
- )
- logger.debug("Got response to make_%s: %s", membership, event)
- # We should assert some things.
- # FIXME: Do this in a nicer way
- assert event.type == EventTypes.Member
- assert event.user_id == user_id
- assert event.state_key == user_id
- assert event.room_id == room_id
- return (origin, event, format_ver)
- @defer.inlineCallbacks
- @log_function
- def on_make_leave_request(self, room_id, user_id):
- """ We've received a /make_leave/ request, so we create a partial
- leave event for the room and return that. We do *not* persist or
- process it until the other server has signed it and sent it back.
- """
- room_version = yield self.store.get_room_version(room_id)
- builder = self.event_builder_factory.new(
- room_version,
- {
- "type": EventTypes.Member,
- "content": {"membership": Membership.LEAVE},
- "room_id": room_id,
- "sender": user_id,
- "state_key": user_id,
- },
- )
- event, context = yield self.event_creation_handler.create_new_client_event(
- builder=builder
- )
- event_allowed = yield self.third_party_event_rules.check_event_allowed(
- event, context
- )
- if not event_allowed:
- logger.warning("Creation of leave %s forbidden by third-party rules", event)
- raise SynapseError(
- 403, "This event is not allowed in this context", Codes.FORBIDDEN
- )
- try:
- # The remote hasn't signed it yet, obviously. We'll do the full checks
- # when we get the event back in `on_send_leave_request`
- yield self.auth.check_from_context(
- room_version, event, context, do_sig_check=False
- )
- except AuthError as e:
- logger.warn("Failed to create new leave %r because %s", event, e)
- raise e
- return event
- @defer.inlineCallbacks
- @log_function
- def on_send_leave_request(self, origin, pdu):
- """ We have received a leave event for a room. Fully process it."""
- event = pdu
- logger.debug(
- "on_send_leave_request: Got event: %s, signatures: %s",
- event.event_id,
- event.signatures,
- )
- event.internal_metadata.outlier = False
- context = yield self._handle_new_event(origin, event)
- event_allowed = yield self.third_party_event_rules.check_event_allowed(
- event, context
- )
- if not event_allowed:
- logger.info("Sending of leave %s forbidden by third-party rules", event)
- raise SynapseError(
- 403, "This event is not allowed in this context", Codes.FORBIDDEN
- )
- logger.debug(
- "on_send_leave_request: After _handle_new_event: %s, sigs: %s",
- event.event_id,
- event.signatures,
- )
- return None
- @defer.inlineCallbacks
- def get_state_for_pdu(self, room_id, event_id):
- """Returns the state at the event. i.e. not including said event.
- """
- event = yield self.store.get_event(
- event_id, allow_none=False, check_room_id=room_id
- )
- state_groups = yield self.store.get_state_groups(room_id, [event_id])
- if state_groups:
- _, state = list(iteritems(state_groups)).pop()
- results = {(e.type, e.state_key): e for e in state}
- if event.is_state():
- # Get previous state
- if "replaces_state" in event.unsigned:
- prev_id = event.unsigned["replaces_state"]
- if prev_id != event.event_id:
- prev_event = yield self.store.get_event(prev_id)
- results[(event.type, event.state_key)] = prev_event
- else:
- del results[(event.type, event.state_key)]
- res = list(results.values())
- return res
- else:
- return []
- @defer.inlineCallbacks
- def get_state_ids_for_pdu(self, room_id, event_id):
- """Returns the state at the event. i.e. not including said event.
- """
- event = yield self.store.get_event(
- event_id, allow_none=False, check_room_id=room_id
- )
- state_groups = yield self.store.get_state_groups_ids(room_id, [event_id])
- if state_groups:
- _, state = list(state_groups.items()).pop()
- results = state
- if event.is_state():
- # Get previous state
- if "replaces_state" in event.unsigned:
- prev_id = event.unsigned["replaces_state"]
- if prev_id != event.event_id:
- results[(event.type, event.state_key)] = prev_id
- else:
- results.pop((event.type, event.state_key), None)
- return list(results.values())
- else:
- return []
- @defer.inlineCallbacks
- @log_function
- def on_backfill_request(self, origin, room_id, pdu_list, limit):
- in_room = yield self.auth.check_host_in_room(room_id, origin)
- if not in_room:
- raise AuthError(403, "Host not in room.")
- events = yield self.store.get_backfill_events(room_id, pdu_list, limit)
- events = yield filter_events_for_server(self.store, origin, events)
- return events
- @defer.inlineCallbacks
- @log_function
- def get_persisted_pdu(self, origin, event_id):
- """Get an event from the database for the given server.
- Args:
- origin [str]: hostname of server which is requesting the event; we
- will check that the server is allowed to see it.
- event_id [str]: id of the event being requested
- Returns:
- Deferred[EventBase|None]: None if we know nothing about the event;
- otherwise the (possibly-redacted) event.
- Raises:
- AuthError if the server is not currently in the room
- """
- event = yield self.store.get_event(
- event_id, allow_none=True, allow_rejected=True
- )
- if event:
- in_room = yield self.auth.check_host_in_room(event.room_id, origin)
- if not in_room:
- raise AuthError(403, "Host not in room.")
- events = yield filter_events_for_server(self.store, origin, [event])
- event = events[0]
- return event
- else:
- return None
- def get_min_depth_for_context(self, context):
- return self.store.get_min_depth(context)
- @defer.inlineCallbacks
- def _handle_new_event(
- self, origin, event, state=None, auth_events=None, backfilled=False
- ):
- context = yield self._prep_event(
- origin, event, state=state, auth_events=auth_events, backfilled=backfilled
- )
- # reraise does not allow inlineCallbacks to preserve the stacktrace, so we
- # hack around with a try/finally instead.
- success = False
- try:
- if not event.internal_metadata.is_outlier() and not backfilled:
- yield self.action_generator.handle_push_actions_for_event(
- event, context
- )
- yield self.persist_events_and_notify(
- [(event, context)], backfilled=backfilled
- )
- success = True
- finally:
- if not success:
- run_in_background(
- self.store.remove_push_actions_from_staging, event.event_id
- )
- return context
- @defer.inlineCallbacks
- def _handle_new_events(self, origin, event_infos, backfilled=False):
- """Creates the appropriate contexts and persists events. The events
- should not depend on one another, e.g. this should be used to persist
- a bunch of outliers, but not a chunk of individual events that depend
- on each other for state calculations.
- Notifies about the events where appropriate.
- """
- @defer.inlineCallbacks
- def prep(ev_info):
- event = ev_info["event"]
- with nested_logging_context(suffix=event.event_id):
- res = yield self._prep_event(
- origin,
- event,
- state=ev_info.get("state"),
- auth_events=ev_info.get("auth_events"),
- backfilled=backfilled,
- )
- return res
- contexts = yield make_deferred_yieldable(
- defer.gatherResults(
- [run_in_background(prep, ev_info) for ev_info in event_infos],
- consumeErrors=True,
- )
- )
- yield self.persist_events_and_notify(
- [
- (ev_info["event"], context)
- for ev_info, context in zip(event_infos, contexts)
- ],
- backfilled=backfilled,
- )
- @defer.inlineCallbacks
- def _persist_auth_tree(self, origin, auth_events, state, event):
- """Checks the auth chain is valid (and passes auth checks) for the
- state and event. Then persists the auth chain and state atomically.
- Persists the event separately. Notifies about the persisted events
- where appropriate.
- Will attempt to fetch missing auth events.
- Args:
- origin (str): Where the events came from
- auth_events (list)
- state (list)
- event (Event)
- Returns:
- Deferred
- """
- events_to_context = {}
- for e in itertools.chain(auth_events, state):
- e.internal_metadata.outlier = True
- ctx = yield self.state_handler.compute_event_context(e)
- events_to_context[e.event_id] = ctx
- event_map = {
- e.event_id: e for e in itertools.chain(auth_events, state, [event])
- }
- create_event = None
- for e in auth_events:
- if (e.type, e.state_key) == (EventTypes.Create, ""):
- create_event = e
- break
- if create_event is None:
- # If the state doesn't have a create event then the room is
- # invalid, and it would fail auth checks anyway.
- raise SynapseError(400, "No create event in state")
- room_version = create_event.content.get(
- "room_version", RoomVersions.V1.identifier
- )
- missing_auth_events = set()
- for e in itertools.chain(auth_events, state, [event]):
- for e_id in e.auth_event_ids():
- if e_id not in event_map:
- missing_auth_events.add(e_id)
- for e_id in missing_auth_events:
- m_ev = yield self.federation_client.get_pdu(
- [origin], e_id, room_version=room_version, outlier=True, timeout=10000
- )
- if m_ev and m_ev.event_id == e_id:
- event_map[e_id] = m_ev
- else:
- logger.info("Failed to find auth event %r", e_id)
- for e in itertools.chain(auth_events, state, [event]):
- auth_for_e = {
- (event_map[e_id].type, event_map[e_id].state_key): event_map[e_id]
- for e_id in e.auth_event_ids()
- if e_id in event_map
- }
- if create_event:
- auth_for_e[(EventTypes.Create, "")] = create_event
- try:
- self.auth.check(room_version, e, auth_events=auth_for_e)
- except SynapseError as err:
- # we may get SynapseErrors here as well as AuthErrors. For
- # instance, there are a couple of (ancient) events in some
- # rooms whose senders do not have the correct sigil; these
- # cause SynapseErrors in auth.check. We don't want to give up
- # the attempt to federate altogether in such cases.
- logger.warn("Rejecting %s because %s", e.event_id, err.msg)
- if e == event:
- raise
- events_to_context[e.event_id].rejected = RejectedReason.AUTH_ERROR
- yield self.persist_events_and_notify(
- [
- (e, events_to_context[e.event_id])
- for e in itertools.chain(auth_events, state)
- ]
- )
- new_event_context = yield self.state_handler.compute_event_context(
- event, old_state=state
- )
- yield self.persist_events_and_notify([(event, new_event_context)])
- @defer.inlineCallbacks
- def _prep_event(self, origin, event, state, auth_events, backfilled):
- """
- Args:
- origin:
- event:
- state:
- auth_events:
- backfilled (bool)
- Returns:
- Deferred, which resolves to synapse.events.snapshot.EventContext
- """
- context = yield self.state_handler.compute_event_context(event, old_state=state)
- if not auth_events:
- prev_state_ids = yield context.get_prev_state_ids(self.store)
- auth_events_ids = yield self.auth.compute_auth_events(
- event, 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()}
- # This is a hack to fix some old rooms where the initial join event
- # didn't reference the create event in its auth events.
- if event.type == EventTypes.Member and not event.auth_event_ids():
- if len(event.prev_event_ids()) == 1 and event.depth < 5:
- c = yield self.store.get_event(
- event.prev_event_ids()[0], allow_none=True
- )
- if c and c.type == EventTypes.Create:
- auth_events[(c.type, c.state_key)] = c
- try:
- yield self.do_auth(origin, event, context, auth_events=auth_events)
- except AuthError as e:
- logger.warn("[%s %s] Rejecting: %s", event.room_id, event.event_id, e.msg)
- context.rejected = RejectedReason.AUTH_ERROR
- if not context.rejected:
- yield self._check_for_soft_fail(event, state, backfilled)
- if event.type == EventTypes.GuestAccess and not context.rejected:
- yield self.maybe_kick_guest_users(event)
- return context
- @defer.inlineCallbacks
- def _check_for_soft_fail(self, event, state, backfilled):
- """Checks if we should soft fail the event, if so marks the event as
- such.
- Args:
- event (FrozenEvent)
- state (dict|None): The state at the event if we don't have all the
- event's prev events
- backfilled (bool): Whether the event is from backfill
- Returns:
- Deferred
- """
- # For new (non-backfilled and non-outlier) events we check if the event
- # passes auth based on the current state. If it doesn't then we
- # "soft-fail" the event.
- do_soft_fail_check = not backfilled and not event.internal_metadata.is_outlier()
- if do_soft_fail_check:
- extrem_ids = yield self.store.get_latest_event_ids_in_room(event.room_id)
- extrem_ids = set(extrem_ids)
- prev_event_ids = set(event.prev_event_ids())
- if extrem_ids == prev_event_ids:
- # If they're the same then the current state is the same as the
- # state at the event, so no point rechecking auth for soft fail.
- do_soft_fail_check = False
- if do_soft_fail_check:
- room_version = yield self.store.get_room_version(event.room_id)
- # Calculate the "current state".
- if state is not None:
- # If we're explicitly given the state then we won't have all the
- # prev events, and so we have a gap in the graph. In this case
- # we want to be a little careful as we might have been down for
- # a while and have an incorrect view of the current state,
- # however we still want to do checks as gaps are easy to
- # maliciously manufacture.
- #
- # So we use a "current state" that is actually a state
- # resolution across the current forward extremities and the
- # given state at the event. This should correctly handle cases
- # like bans, especially with state res v2.
- state_sets = yield self.store.get_state_groups(
- event.room_id, extrem_ids
- )
- state_sets = list(state_sets.values())
- state_sets.append(state)
- current_state_ids = yield self.state_handler.resolve_events(
- room_version, state_sets, event
- )
- current_state_ids = {
- k: e.event_id for k, e in iteritems(current_state_ids)
- }
- else:
- current_state_ids = yield self.state_handler.get_current_state_ids(
- event.room_id, latest_event_ids=extrem_ids
- )
- logger.debug(
- "Doing soft-fail check for %s: state %s",
- event.event_id,
- current_state_ids,
- )
- # Now check if event pass auth against said current state
- auth_types = auth_types_for_event(event)
- current_state_ids = [
- e for k, e in iteritems(current_state_ids) if k in auth_types
- ]
- current_auth_events = yield self.store.get_events(current_state_ids)
- current_auth_events = {
- (e.type, e.state_key): e for e in current_auth_events.values()
- }
- try:
- self.auth.check(room_version, event, auth_events=current_auth_events)
- except AuthError as e:
- logger.warn("Soft-failing %r because %s", event, e)
- event.internal_metadata.soft_failed = True
- @defer.inlineCallbacks
- def on_query_auth(
- self, origin, event_id, room_id, remote_auth_chain, rejects, missing
- ):
- in_room = yield self.auth.check_host_in_room(room_id, origin)
- if not in_room:
- raise AuthError(403, "Host not in room.")
- event = yield self.store.get_event(
- event_id, allow_none=False, check_room_id=room_id
- )
- # Just go through and process each event in `remote_auth_chain`. We
- # don't want to fall into the trap of `missing` being wrong.
- for e in remote_auth_chain:
- try:
- yield self._handle_new_event(origin, e)
- except AuthError:
- pass
- # Now get the current auth_chain for the event.
- local_auth_chain = yield self.store.get_auth_chain(
- [auth_id for auth_id in event.auth_event_ids()], include_given=True
- )
- # TODO: Check if we would now reject event_id. If so we need to tell
- # everyone.
- ret = yield self.construct_auth_difference(local_auth_chain, remote_auth_chain)
- logger.debug("on_query_auth returning: %s", ret)
- return ret
- @defer.inlineCallbacks
- def on_get_missing_events(
- self, origin, room_id, earliest_events, latest_events, limit
- ):
- in_room = yield self.auth.check_host_in_room(room_id, origin)
- if not in_room:
- raise AuthError(403, "Host not in room.")
- limit = min(limit, 20)
- missing_events = yield self.store.get_missing_events(
- room_id=room_id,
- earliest_events=earliest_events,
- latest_events=latest_events,
- limit=limit,
- )
- missing_events = yield filter_events_for_server(
- self.store, origin, missing_events
- )
- return missing_events
- @defer.inlineCallbacks
- @log_function
- def do_auth(self, origin, event, context, auth_events):
- """
- Args:
- origin (str):
- event (synapse.events.EventBase):
- context (synapse.events.snapshot.EventContext):
- auth_events (dict[(str, str)->synapse.events.EventBase]):
- Map from (event_type, state_key) to event
- What we expect the event's auth_events to be, based on the event's
- position in the dag. I think? maybe??
- Also NB that this function adds entries to it.
- Returns:
- defer.Deferred[None]
- """
- room_version = yield self.store.get_room_version(event.room_id)
- try:
- yield self._update_auth_events_and_context_for_auth(
- origin, event, context, auth_events
- )
- except Exception:
- # We don't really mind if the above fails, so lets not fail
- # processing if it does. However, it really shouldn't fail so
- # let's still log as an exception since we'll still want to fix
- # any bugs.
- logger.exception(
- "Failed to double check auth events for %s with remote. "
- "Ignoring failure and continuing processing of event.",
- event.event_id,
- )
- try:
- self.auth.check(room_version, event, auth_events=auth_events)
- except AuthError as e:
- logger.warn("Failed auth resolution for %r because %s", event, e)
- raise e
- @defer.inlineCallbacks
- def _update_auth_events_and_context_for_auth(
- self, origin, event, context, auth_events
- ):
- """Helper for do_auth. See there for docs.
- Checks whether a given event has the expected auth events. If it
- doesn't then we talk to the remote server to compare state to see if
- we can come to a consensus (e.g. if one server missed some valid
- state).
- This attempts to resovle any potential divergence of state between
- servers, but is not essential and so failures should not block further
- processing of the event.
- Args:
- origin (str):
- event (synapse.events.EventBase):
- context (synapse.events.snapshot.EventContext):
- auth_events (dict[(str, str)->synapse.events.EventBase]):
- Returns:
- defer.Deferred[None]
- """
- event_auth_events = set(event.auth_event_ids())
- if event.is_state():
- event_key = (event.type, event.state_key)
- else:
- event_key = None
- # if the event's auth_events refers to events which are not in our
- # calculated auth_events, we need to fetch those events from somewhere.
- #
- # we start by fetching them from the store, and then try calling /event_auth/.
- missing_auth = event_auth_events.difference(
- e.event_id for e in auth_events.values()
- )
- if missing_auth:
- # TODO: can we use store.have_seen_events here instead?
- have_events = yield self.store.get_seen_events_with_rejections(missing_auth)
- logger.debug("Got events %s from store", have_events)
- missing_auth.difference_update(have_events.keys())
- else:
- have_events = {}
- have_events.update({e.event_id: "" for e in auth_events.values()})
- if missing_auth:
- # If we don't have all the auth events, we need to get them.
- logger.info("auth_events contains unknown events: %s", missing_auth)
- try:
- try:
- remote_auth_chain = yield self.federation_client.get_event_auth(
- origin, event.room_id, event.event_id
- )
- except RequestSendFailed as e:
- # The other side isn't around or doesn't implement the
- # endpoint, so lets just bail out.
- logger.info("Failed to get event auth from remote: %s", e)
- return
- seen_remotes = yield self.store.have_seen_events(
- [e.event_id for e in remote_auth_chain]
- )
- for e in remote_auth_chain:
- if e.event_id in seen_remotes:
- continue
- if e.event_id == event.event_id:
- continue
- try:
- auth_ids = e.auth_event_ids()
- auth = {
- (e.type, e.state_key): e
- for e in remote_auth_chain
- if e.event_id in auth_ids or e.type == EventTypes.Create
- }
- e.internal_metadata.outlier = True
- logger.debug(
- "do_auth %s missing_auth: %s", event.event_id, e.event_id
- )
- yield self._handle_new_event(origin, e, auth_events=auth)
- if e.event_id in event_auth_events:
- auth_events[(e.type, e.state_key)] = e
- except AuthError:
- pass
- have_events = yield self.store.get_seen_events_with_rejections(
- event.auth_event_ids()
- )
- except Exception:
- # FIXME:
- logger.exception("Failed to get auth chain")
- if event.internal_metadata.is_outlier():
- logger.info("Skipping auth_event fetch for outlier")
- return
- # FIXME: Assumes we have and stored all the state for all the
- # prev_events
- different_auth = event_auth_events.difference(
- e.event_id for e in auth_events.values()
- )
- if not different_auth:
- return
- logger.info(
- "auth_events refers to events which are not in our calculated auth "
- "chain: %s",
- different_auth,
- )
- room_version = yield self.store.get_room_version(event.room_id)
- different_events = yield make_deferred_yieldable(
- defer.gatherResults(
- [
- run_in_background(
- self.store.get_event, d, allow_none=True, allow_rejected=False
- )
- for d in different_auth
- if d in have_events and not have_events[d]
- ],
- consumeErrors=True,
- )
- ).addErrback(unwrapFirstError)
- if different_events:
- local_view = dict(auth_events)
- remote_view = dict(auth_events)
- remote_view.update(
- {(d.type, d.state_key): d for d in different_events if d}
- )
- new_state = yield self.state_handler.resolve_events(
- room_version,
- [list(local_view.values()), list(remote_view.values())],
- event,
- )
- logger.info(
- "After state res: updating auth_events with new state %s",
- {
- (d.type, d.state_key): d.event_id
- for d in new_state.values()
- if auth_events.get((d.type, d.state_key)) != d
- },
- )
- auth_events.update(new_state)
- different_auth = event_auth_events.difference(
- e.event_id for e in auth_events.values()
- )
- yield self._update_context_for_auth_events(
- event, context, auth_events, event_key
- )
- if not different_auth:
- # we're done
- return
- logger.info(
- "auth_events still refers to events which are not in the calculated auth "
- "chain after state resolution: %s",
- different_auth,
- )
- # Only do auth resolution if we have something new to say.
- # We can't prove an auth failure.
- do_resolution = False
- for e_id in different_auth:
- if e_id in have_events:
- if have_events[e_id] == RejectedReason.NOT_ANCESTOR:
- do_resolution = True
- break
- if not do_resolution:
- logger.info(
- "Skipping auth resolution due to lack of provable rejection reasons"
- )
- return
- logger.info("Doing auth resolution")
- prev_state_ids = yield context.get_prev_state_ids(self.store)
- # 1. Get what we think is the auth chain.
- auth_ids = yield self.auth.compute_auth_events(event, prev_state_ids)
- local_auth_chain = yield self.store.get_auth_chain(auth_ids, include_given=True)
- try:
- # 2. Get remote difference.
- try:
- result = yield self.federation_client.query_auth(
- origin, event.room_id, event.event_id, local_auth_chain
- )
- except RequestSendFailed as e:
- # The other side isn't around or doesn't implement the
- # endpoint, so lets just bail out.
- logger.info("Failed to query auth from remote: %s", e)
- return
- seen_remotes = yield self.store.have_seen_events(
- [e.event_id for e in result["auth_chain"]]
- )
- # 3. Process any remote auth chain events we haven't seen.
- for ev in result["auth_chain"]:
- if ev.event_id in seen_remotes:
- continue
- if ev.event_id == event.event_id:
- continue
- try:
- auth_ids = ev.auth_event_ids()
- auth = {
- (e.type, e.state_key): e
- for e in result["auth_chain"]
- if e.event_id in auth_ids or event.type == EventTypes.Create
- }
- ev.internal_metadata.outlier = True
- logger.debug(
- "do_auth %s different_auth: %s", event.event_id, e.event_id
- )
- yield self._handle_new_event(origin, ev, auth_events=auth)
- if ev.event_id in event_auth_events:
- auth_events[(ev.type, ev.state_key)] = ev
- except AuthError:
- pass
- except Exception:
- # FIXME:
- logger.exception("Failed to query auth chain")
- # 4. Look at rejects and their proofs.
- # TODO.
- yield self._update_context_for_auth_events(
- event, context, auth_events, event_key
- )
- @defer.inlineCallbacks
- def _update_context_for_auth_events(self, event, context, auth_events, event_key):
- """Update the state_ids in an event context after auth event resolution,
- storing the changes as a new state group.
- Args:
- event (Event): The event we're handling the context for
- context (synapse.events.snapshot.EventContext): event context
- to be updated
- auth_events (dict[(str, str)->str]): Events to update in the event
- context.
- event_key ((str, str)): (type, state_key) for the current event.
- this will not be included in the current_state in the context.
- """
- state_updates = {
- k: a.event_id for k, a in iteritems(auth_events) if k != event_key
- }
- current_state_ids = yield context.get_current_state_ids(self.store)
- current_state_ids = dict(current_state_ids)
- current_state_ids.update(state_updates)
- prev_state_ids = yield context.get_prev_state_ids(self.store)
- prev_state_ids = dict(prev_state_ids)
- prev_state_ids.update({k: a.event_id for k, a in iteritems(auth_events)})
- # create a new state group as a delta from the existing one.
- prev_group = context.state_group
- state_group = yield self.store.store_state_group(
- event.event_id,
- event.room_id,
- prev_group=prev_group,
- delta_ids=state_updates,
- current_state_ids=current_state_ids,
- )
- yield context.update_state(
- state_group=state_group,
- current_state_ids=current_state_ids,
- prev_state_ids=prev_state_ids,
- prev_group=prev_group,
- delta_ids=state_updates,
- )
- @defer.inlineCallbacks
- def construct_auth_difference(self, local_auth, remote_auth):
- """ Given a local and remote auth chain, find the differences. This
- assumes that we have already processed all events in remote_auth
- Params:
- local_auth (list)
- remote_auth (list)
- Returns:
- dict
- """
- logger.debug("construct_auth_difference Start!")
- # TODO: Make sure we are OK with local_auth or remote_auth having more
- # auth events in them than strictly necessary.
- def sort_fun(ev):
- return ev.depth, ev.event_id
- logger.debug("construct_auth_difference after sort_fun!")
- # We find the differences by starting at the "bottom" of each list
- # and iterating up on both lists. The lists are ordered by depth and
- # then event_id, we iterate up both lists until we find the event ids
- # don't match. Then we look at depth/event_id to see which side is
- # missing that event, and iterate only up that list. Repeat.
- remote_list = list(remote_auth)
- remote_list.sort(key=sort_fun)
- local_list = list(local_auth)
- local_list.sort(key=sort_fun)
- local_iter = iter(local_list)
- remote_iter = iter(remote_list)
- logger.debug("construct_auth_difference before get_next!")
- def get_next(it, opt=None):
- try:
- return next(it)
- except Exception:
- return opt
- current_local = get_next(local_iter)
- current_remote = get_next(remote_iter)
- logger.debug("construct_auth_difference before while")
- missing_remotes = []
- missing_locals = []
- while current_local or current_remote:
- if current_remote is None:
- missing_locals.append(current_local)
- current_local = get_next(local_iter)
- continue
- if current_local is None:
- missing_remotes.append(current_remote)
- current_remote = get_next(remote_iter)
- continue
- if current_local.event_id == current_remote.event_id:
- current_local = get_next(local_iter)
- current_remote = get_next(remote_iter)
- continue
- if current_local.depth < current_remote.depth:
- missing_locals.append(current_local)
- current_local = get_next(local_iter)
- continue
- if current_local.depth > current_remote.depth:
- missing_remotes.append(current_remote)
- current_remote = get_next(remote_iter)
- continue
- # They have the same depth, so we fall back to the event_id order
- if current_local.event_id < current_remote.event_id:
- missing_locals.append(current_local)
- current_local = get_next(local_iter)
- if current_local.event_id > current_remote.event_id:
- missing_remotes.append(current_remote)
- current_remote = get_next(remote_iter)
- continue
- logger.debug("construct_auth_difference after while")
- # missing locals should be sent to the server
- # We should find why we are missing remotes, as they will have been
- # rejected.
- # Remove events from missing_remotes if they are referencing a missing
- # remote. We only care about the "root" rejected ones.
- missing_remote_ids = [e.event_id for e in missing_remotes]
- base_remote_rejected = list(missing_remotes)
- for e in missing_remotes:
- for e_id in e.auth_event_ids():
- if e_id in missing_remote_ids:
- try:
- base_remote_rejected.remove(e)
- except ValueError:
- pass
- reason_map = {}
- for e in base_remote_rejected:
- reason = yield self.store.get_rejection_reason(e.event_id)
- if reason is None:
- # TODO: e is not in the current state, so we should
- # construct some proof of that.
- continue
- reason_map[e.event_id] = reason
- if reason == RejectedReason.AUTH_ERROR:
- pass
- elif reason == RejectedReason.REPLACED:
- # TODO: Get proof
- pass
- elif reason == RejectedReason.NOT_ANCESTOR:
- # TODO: Get proof.
- pass
- logger.debug("construct_auth_difference returning")
- return {
- "auth_chain": local_auth,
- "rejects": {
- e.event_id: {"reason": reason_map[e.event_id], "proof": None}
- for e in base_remote_rejected
- },
- "missing": [e.event_id for e in missing_locals],
- }
- @defer.inlineCallbacks
- @log_function
- def exchange_third_party_invite(
- self, sender_user_id, target_user_id, room_id, signed
- ):
- third_party_invite = {"signed": signed}
- event_dict = {
- "type": EventTypes.Member,
- "content": {
- "membership": Membership.INVITE,
- "third_party_invite": third_party_invite,
- },
- "room_id": room_id,
- "sender": sender_user_id,
- "state_key": target_user_id,
- }
- if (yield self.auth.check_host_in_room(room_id, self.hs.hostname)):
- room_version = yield self.store.get_room_version(room_id)
- builder = self.event_builder_factory.new(room_version, event_dict)
- EventValidator().validate_builder(builder)
- event, context = yield self.event_creation_handler.create_new_client_event(
- builder=builder
- )
- event_allowed = yield self.third_party_event_rules.check_event_allowed(
- event, context
- )
- if not event_allowed:
- logger.info(
- "Creation of threepid invite %s forbidden by third-party rules",
- event,
- )
- raise SynapseError(
- 403, "This event is not allowed in this context", Codes.FORBIDDEN
- )
- event, context = yield self.add_display_name_to_third_party_invite(
- room_version, event_dict, event, context
- )
- EventValidator().validate_new(event)
- # We need to tell the transaction queue to send this out, even
- # though the sender isn't a local user.
- event.internal_metadata.send_on_behalf_of = self.hs.hostname
- try:
- yield self.auth.check_from_context(room_version, event, context)
- except AuthError as e:
- logger.warn("Denying new third party invite %r because %s", event, e)
- raise e
- yield self._check_signature(event, context)
- member_handler = self.hs.get_room_member_handler()
- yield member_handler.send_membership_event(None, event, context)
- else:
- destinations = set(x.split(":", 1)[-1] for x in (sender_user_id, room_id))
- yield self.federation_client.forward_third_party_invite(
- destinations, room_id, event_dict
- )
- @defer.inlineCallbacks
- @log_function
- def on_exchange_third_party_invite_request(self, origin, room_id, event_dict):
- """Handle an exchange_third_party_invite request from a remote server
- The remote server will call this when it wants to turn a 3pid invite
- into a normal m.room.member invite.
- Returns:
- Deferred: resolves (to None)
- """
- room_version = yield self.store.get_room_version(room_id)
- # NB: event_dict has a particular specced format we might need to fudge
- # if we change event formats too much.
- builder = self.event_builder_factory.new(room_version, event_dict)
- event, context = yield self.event_creation_handler.create_new_client_event(
- builder=builder
- )
- event_allowed = yield self.third_party_event_rules.check_event_allowed(
- event, context
- )
- if not event_allowed:
- logger.warning(
- "Exchange of threepid invite %s forbidden by third-party rules", event
- )
- raise SynapseError(
- 403, "This event is not allowed in this context", Codes.FORBIDDEN
- )
- event, context = yield self.add_display_name_to_third_party_invite(
- room_version, event_dict, event, context
- )
- try:
- self.auth.check_from_context(room_version, event, context)
- except AuthError as e:
- logger.warn("Denying third party invite %r because %s", event, e)
- raise e
- yield self._check_signature(event, context)
- # We need to tell the transaction queue to send this out, even
- # though the sender isn't a local user.
- event.internal_metadata.send_on_behalf_of = get_domain_from_id(event.sender)
- member_handler = self.hs.get_room_member_handler()
- yield member_handler.send_membership_event(None, event, context)
- @defer.inlineCallbacks
- def add_display_name_to_third_party_invite(
- self, room_version, event_dict, event, context
- ):
- key = (
- EventTypes.ThirdPartyInvite,
- event.content["third_party_invite"]["signed"]["token"],
- )
- original_invite = None
- prev_state_ids = yield context.get_prev_state_ids(self.store)
- original_invite_id = prev_state_ids.get(key)
- if original_invite_id:
- original_invite = yield self.store.get_event(
- original_invite_id, allow_none=True
- )
- if original_invite:
- display_name = original_invite.content["display_name"]
- event_dict["content"]["third_party_invite"]["display_name"] = display_name
- else:
- logger.info(
- "Could not find invite event for third_party_invite: %r", event_dict
- )
- # We don't discard here as this is not the appropriate place to do
- # auth checks. If we need the invite and don't have it then the
- # auth check code will explode appropriately.
- builder = self.event_builder_factory.new(room_version, event_dict)
- EventValidator().validate_builder(builder)
- event, context = yield self.event_creation_handler.create_new_client_event(
- builder=builder
- )
- EventValidator().validate_new(event)
- return (event, context)
- @defer.inlineCallbacks
- def _check_signature(self, event, context):
- """
- Checks that the signature in the event is consistent with its invite.
- Args:
- event (Event): The m.room.member event to check
- context (EventContext):
- Raises:
- AuthError: if signature didn't match any keys, or key has been
- revoked,
- SynapseError: if a transient error meant a key couldn't be checked
- for revocation.
- """
- signed = event.content["third_party_invite"]["signed"]
- token = signed["token"]
- prev_state_ids = yield context.get_prev_state_ids(self.store)
- invite_event_id = prev_state_ids.get((EventTypes.ThirdPartyInvite, token))
- invite_event = None
- if invite_event_id:
- invite_event = yield self.store.get_event(invite_event_id, allow_none=True)
- if not invite_event:
- raise AuthError(403, "Could not find invite")
- logger.debug("Checking auth on event %r", event.content)
- last_exception = None
- # for each public key in the 3pid invite event
- for public_key_object in self.hs.get_auth().get_public_keys(invite_event):
- try:
- # for each sig on the third_party_invite block of the actual invite
- for server, signature_block in signed["signatures"].items():
- for key_name, encoded_signature in signature_block.items():
- if not key_name.startswith("ed25519:"):
- continue
- logger.debug(
- "Attempting to verify sig with key %s from %r "
- "against pubkey %r",
- key_name,
- server,
- public_key_object,
- )
- try:
- public_key = public_key_object["public_key"]
- verify_key = decode_verify_key_bytes(
- key_name, decode_base64(public_key)
- )
- verify_signed_json(signed, server, verify_key)
- logger.debug(
- "Successfully verified sig with key %s from %r "
- "against pubkey %r",
- key_name,
- server,
- public_key_object,
- )
- except Exception:
- logger.info(
- "Failed to verify sig with key %s from %r "
- "against pubkey %r",
- key_name,
- server,
- public_key_object,
- )
- raise
- try:
- if "key_validity_url" in public_key_object:
- yield self._check_key_revocation(
- public_key, public_key_object["key_validity_url"]
- )
- except Exception:
- logger.info(
- "Failed to query key_validity_url %s",
- public_key_object["key_validity_url"],
- )
- raise
- return
- except Exception as e:
- last_exception = e
- raise last_exception
- @defer.inlineCallbacks
- def _check_key_revocation(self, public_key, url):
- """
- Checks whether public_key has been revoked.
- Args:
- public_key (str): base-64 encoded public key.
- url (str): Key revocation URL.
- Raises:
- AuthError: if they key has been revoked.
- SynapseError: if a transient error meant a key couldn't be checked
- for revocation.
- """
- try:
- response = yield self.http_client.get_json(url, {"public_key": public_key})
- except Exception:
- raise SynapseError(502, "Third party certificate could not be checked")
- if "valid" not in response or not response["valid"]:
- raise AuthError(403, "Third party certificate was invalid")
- @defer.inlineCallbacks
- def persist_events_and_notify(self, event_and_contexts, backfilled=False):
- """Persists events and tells the notifier/pushers about them, if
- necessary.
- Args:
- event_and_contexts(list[tuple[FrozenEvent, EventContext]])
- backfilled (bool): Whether these events are a result of
- backfilling or not
- Returns:
- Deferred
- """
- if self.config.worker_app:
- yield self._send_events_to_master(
- store=self.store,
- event_and_contexts=event_and_contexts,
- backfilled=backfilled,
- )
- else:
- max_stream_id = yield self.store.persist_events(
- event_and_contexts, backfilled=backfilled
- )
- if not backfilled: # Never notify for backfilled events
- for event, _ in event_and_contexts:
- yield self._notify_persisted_event(event, max_stream_id)
- def _notify_persisted_event(self, event, max_stream_id):
- """Checks to see if notifier/pushers should be notified about the
- event or not.
- Args:
- event (FrozenEvent)
- max_stream_id (int): The max_stream_id returned by persist_events
- """
- extra_users = []
- if event.type == EventTypes.Member:
- target_user_id = event.state_key
- # We notify for memberships if its an invite for one of our
- # users
- if event.internal_metadata.is_outlier():
- if event.membership != Membership.INVITE:
- if not self.is_mine_id(target_user_id):
- return
- target_user = UserID.from_string(target_user_id)
- extra_users.append(target_user)
- elif event.internal_metadata.is_outlier():
- return
- event_stream_id = event.internal_metadata.stream_ordering
- self.notifier.on_new_room_event(
- event, event_stream_id, max_stream_id, extra_users=extra_users
- )
- return self.pusher_pool.on_new_notifications(event_stream_id, max_stream_id)
- def _clean_room_for_join(self, room_id):
- """Called to clean up any data in DB for a given room, ready for the
- server to join the room.
- Args:
- room_id (str)
- """
- if self.config.worker_app:
- return self._clean_room_for_join_client(room_id)
- else:
- return self.store.clean_room_for_join(room_id)
- def user_joined_room(self, user, room_id):
- """Called when a new user has joined the room
- """
- if self.config.worker_app:
- return self._notify_user_membership_change(
- room_id=room_id, user_id=user.to_string(), change="joined"
- )
- else:
- return user_joined_room(self.distributor, user, room_id)
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