diff options
Diffstat (limited to 'synapse/handlers/federation.py')
| -rw-r--r-- | synapse/handlers/federation.py | 429 |
1 files changed, 310 insertions, 119 deletions
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index bcdcc90a18..40836e0c51 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -17,19 +17,16 @@ from ._base import BaseHandler -from synapse.events.utils import prune_event from synapse.api.errors import ( - AuthError, FederationError, SynapseError, StoreError, + AuthError, FederationError, StoreError, ) -from synapse.api.constants import EventTypes, Membership +from synapse.api.constants import EventTypes, Membership, RejectedReason from synapse.util.logutils import log_function from synapse.util.async import run_on_reactor from synapse.crypto.event_signing import ( - compute_event_signature, check_event_content_hash, - add_hashes_and_signatures, + compute_event_signature, add_hashes_and_signatures, ) from synapse.types import UserID -from syutil.jsonutil import encode_canonical_json from twisted.internet import defer @@ -113,33 +110,6 @@ class FederationHandler(BaseHandler): logger.debug("Processing event: %s", event.event_id) - redacted_event = prune_event(event) - - redacted_pdu_json = redacted_event.get_pdu_json() - try: - yield self.keyring.verify_json_for_server( - event.origin, redacted_pdu_json - ) - except SynapseError as e: - logger.warn( - "Signature check failed for %s redacted to %s", - encode_canonical_json(pdu.get_pdu_json()), - encode_canonical_json(redacted_pdu_json), - ) - raise FederationError( - "ERROR", - e.code, - e.msg, - affected=event.event_id, - ) - - if not check_event_content_hash(event): - logger.warn( - "Event content has been tampered, redacting %s, %s", - event.event_id, encode_canonical_json(event.get_dict()) - ) - event = redacted_event - logger.debug("Event: %s", event) # FIXME (erikj): Awful hack to make the case where we are not currently @@ -149,41 +119,20 @@ class FederationHandler(BaseHandler): event.room_id, self.server_name ) - if not is_in_room and not event.internal_metadata.outlier: + if not is_in_room and not event.internal_metadata.is_outlier(): logger.debug("Got event for room we're not in.") - - replication = self.replication_layer - - if not state: - state, auth_chain = yield replication.get_state_for_room( - origin, context=event.room_id, event_id=event.event_id, - ) - - if not auth_chain: - auth_chain = yield replication.get_event_auth( - origin, - context=event.room_id, - event_id=event.event_id, - ) - - for e in auth_chain: - e.internal_metadata.outlier = True - try: - yield self._handle_new_event(e, fetch_auth_from=origin) - except: - logger.exception( - "Failed to handle auth event %s", - e.event_id, - ) - current_state = state - if state: + if state and auth_chain is not None: for e in state: - logging.info("A :) %r", e) e.internal_metadata.outlier = True try: - yield self._handle_new_event(e) + auth_ids = [e_id for e_id, _ in e.auth_events] + auth = { + (e.type, e.state_key): e for e in auth_chain + if e.event_id in auth_ids + } + yield self._handle_new_event(origin, e, auth_events=auth) except: logger.exception( "Failed to handle state event %s", @@ -192,6 +141,7 @@ class FederationHandler(BaseHandler): try: yield self._handle_new_event( + origin, event, state=state, backfilled=backfilled, @@ -394,7 +344,14 @@ class FederationHandler(BaseHandler): for e in auth_chain: e.internal_metadata.outlier = True try: - yield self._handle_new_event(e) + auth_ids = [e_id for e_id, _ in e.auth_events] + auth = { + (e.type, e.state_key): e for e in auth_chain + if e.event_id in auth_ids + } + yield self._handle_new_event( + target_host, e, auth_events=auth + ) except: logger.exception( "Failed to handle auth event %s", @@ -405,8 +362,13 @@ class FederationHandler(BaseHandler): # FIXME: Auth these. e.internal_metadata.outlier = True try: + auth_ids = [e_id for e_id, _ in e.auth_events] + auth = { + (e.type, e.state_key): e for e in auth_chain + if e.event_id in auth_ids + } yield self._handle_new_event( - e, fetch_auth_from=target_host + target_host, e, auth_events=auth ) except: logger.exception( @@ -415,6 +377,7 @@ class FederationHandler(BaseHandler): ) yield self._handle_new_event( + target_host, new_event, state=state, current_state=state, @@ -481,7 +444,7 @@ class FederationHandler(BaseHandler): event.internal_metadata.outlier = False - context = yield self._handle_new_event(event) + context = yield self._handle_new_event(origin, event) logger.debug( "on_send_join_request: After _handle_new_event: %s, sigs: %s", @@ -682,11 +645,12 @@ class FederationHandler(BaseHandler): waiters.pop().callback(None) @defer.inlineCallbacks - def _handle_new_event(self, event, state=None, backfilled=False, - current_state=None, fetch_auth_from=None): + @log_function + def _handle_new_event(self, origin, event, state=None, backfilled=False, + current_state=None, auth_events=None): logger.debug( - "_handle_new_event: Before annotate: %s, sigs: %s", + "_handle_new_event: %s, sigs: %s", event.event_id, event.signatures, ) @@ -694,65 +658,44 @@ class FederationHandler(BaseHandler): event, old_state=state ) + if not auth_events: + auth_events = context.auth_events + logger.debug( - "_handle_new_event: Before auth fetch: %s, sigs: %s", - event.event_id, event.signatures, + "_handle_new_event: %s, auth_events: %s", + event.event_id, auth_events, ) is_new_state = not event.internal_metadata.is_outlier() - known_ids = set( - [s.event_id for s in context.auth_events.values()] - ) - - for e_id, _ in event.auth_events: - if e_id not in known_ids: - e = yield self.store.get_event(e_id, allow_none=True) - - if not e and fetch_auth_from is not None: - # Grab the auth_chain over federation if we are missing - # auth events. - auth_chain = yield self.replication_layer.get_event_auth( - fetch_auth_from, event.event_id, event.room_id - ) - for auth_event in auth_chain: - yield self._handle_new_event(auth_event) - e = yield self.store.get_event(e_id, allow_none=True) - - if not e: - # TODO: Do some conflict res to make sure that we're - # not the ones who are wrong. - logger.info( - "Rejecting %s as %s not in db or %s", - event.event_id, e_id, known_ids, - ) - # FIXME: How does raising AuthError work with federation? - raise AuthError(403, "Cannot find auth event") - - context.auth_events[(e.type, e.state_key)] = e - - logger.debug( - "_handle_new_event: Before hack: %s, sigs: %s", - event.event_id, event.signatures, - ) - + # 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_events: if len(event.prev_events) == 1: c = yield self.store.get_event(event.prev_events[0][0]) if c.type == EventTypes.Create: - context.auth_events[(c.type, c.state_key)] = c + auth_events[(c.type, c.state_key)] = c - logger.debug( - "_handle_new_event: Before auth check: %s, sigs: %s", - event.event_id, event.signatures, - ) + try: + yield self.do_auth( + origin, event, context, auth_events=auth_events + ) + except AuthError as e: + logger.warn( + "Rejecting %s because %s", + event.event_id, e.msg + ) - self.auth.check(event, auth_events=context.auth_events) + context.rejected = RejectedReason.AUTH_ERROR - logger.debug( - "_handle_new_event: Before persist_event: %s, sigs: %s", - event.event_id, event.signatures, - ) + yield self.store.persist_event( + event, + context=context, + backfilled=backfilled, + is_new_state=False, + current_state=current_state, + ) + raise yield self.store.persist_event( event, @@ -762,9 +705,257 @@ class FederationHandler(BaseHandler): current_state=current_state, ) - logger.debug( - "_handle_new_event: After persist_event: %s, sigs: %s", - event.event_id, event.signatures, + defer.returnValue(context) + + @defer.inlineCallbacks + def on_query_auth(self, origin, event_id, remote_auth_chain, rejects, + missing): + # 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([event_id]) + + # 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 ) - defer.returnValue(context) + logger.debug("on_query_auth reutrning: %s", ret) + + defer.returnValue(ret) + + @defer.inlineCallbacks + @log_function + def do_auth(self, origin, event, context, auth_events): + # Check if we have all the auth events. + res = yield self.store.have_events( + [e_id for e_id, _ in event.auth_events] + ) + + event_auth_events = set(e_id for e_id, _ in event.auth_events) + seen_events = set(res.keys()) + + missing_auth = event_auth_events - seen_events + + if missing_auth: + logger.debug("Missing auth: %s", missing_auth) + # If we don't have all the auth events, we need to get them. + remote_auth_chain = yield self.replication_layer.get_event_auth( + origin, event.room_id, event.event_id + ) + + for e in remote_auth_chain: + try: + auth_ids = [e_id for e_id, _ in e.auth_events] + auth = { + (e.type, e.state_key): e for e in remote_auth_chain + if e.event_id in auth_ids + } + e.internal_metadata.outlier = True + yield self._handle_new_event( + origin, e, auth_events=auth + ) + auth_events[(e.type, e.state_key)] = e + except AuthError: + pass + + # FIXME: Assumes we have and stored all the state for all the + # prev_events + current_state = set(e.event_id for e in auth_events.values()) + different_auth = event_auth_events - current_state + + if different_auth and not event.internal_metadata.is_outlier(): + # Do auth conflict res. + logger.debug("Different auth: %s", different_auth) + + # 1. Get what we think is the auth chain. + auth_ids = self.auth.compute_auth_events(event, context) + local_auth_chain = yield self.store.get_auth_chain(auth_ids) + + # 2. Get remote difference. + result = yield self.replication_layer.query_auth( + origin, + event.room_id, + event.event_id, + local_auth_chain, + ) + + # 3. Process any remote auth chain events we haven't seen. + for missing_id in result.get("missing", []): + try: + for e in result["auth_chain"]: + if e.event_id == missing_id: + ev = e + break + + auth_ids = [e_id for e_id, _ in ev.auth_events] + auth = { + (e.type, e.state_key): e for e in result["auth_chain"] + if e.event_id in auth_ids + } + ev.internal_metadata.outlier = True + 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 + + # 4. Look at rejects and their proofs. + # TODO. + + context.current_state.update(auth_events) + context.state_group = None + + try: + self.auth.check(event, auth_events=auth_events) + except AuthError: + raise + + @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 it.next() + except: + 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_events: + if e_id in missing_remote_ids: + base_remote_rejected.remove(e) + + reason_map = {} + + for e in base_remote_rejected: + reason = yield self.store.get_rejection_reason(e.event_id) + if reason is None: + # FIXME: ERRR?! + logger.warn("Could not find reason for %s", e.event_id) + raise RuntimeError("") + + 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") + + defer.returnValue({ + "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], + }) |