From 77078d6c8ef11e2401406edc1ca340e0d7779267 Mon Sep 17 00:00:00 2001 From: Amber Brown Date: Wed, 27 Jun 2018 11:27:32 +0100 Subject: handle federation not telling us about prev_events --- synapse/handlers/federation.py | 87 ++++++++++++++++++++++++++++++------------ 1 file changed, 62 insertions(+), 25 deletions(-) (limited to 'synapse/handlers/federation.py') diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index b6f8d4cf82..250a5509d8 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -44,6 +44,7 @@ from synapse.util.frozenutils import unfreeze from synapse.crypto.event_signing import ( compute_event_signature, add_hashes_and_signatures, ) +from synapse.state import resolve_events_with_factory from synapse.types import UserID, get_domain_from_id from synapse.events.utils import prune_event @@ -89,7 +90,9 @@ class FederationHandler(BaseHandler): @defer.inlineCallbacks @log_function - def on_receive_pdu(self, origin, pdu, get_missing=True): + def on_receive_pdu( + self, origin, pdu, get_missing=True, sent_to_us_directly=False, + ): """ Process a PDU received via a federation /send/ transaction, or via backfill of missing prev_events @@ -163,7 +166,7 @@ class FederationHandler(BaseHandler): "Ignoring PDU %s for room %s from %s as we've left the room!", pdu.event_id, pdu.room_id, origin, ) - return + defer.returnValue(None) state = None @@ -225,26 +228,54 @@ class FederationHandler(BaseHandler): list(prevs - seen)[:5], ) - if prevs - seen: - logger.info( - "Still missing %d events for room %r: %r...", - len(prevs - seen), pdu.room_id, list(prevs - seen)[:5] + if sent_to_us_directly and prevs - seen: + # If they have sent it to us directly, and the server + # isn't telling us about the auth events that it's + # made a message referencing, we explode + raise FederationError( + "ERROR", + 403, + ("Your server isn't divulging details about prev_events " + "referenced in this event."), + affected=pdu.event_id, ) - fetch_state = True + elif prevs - seen: + # If we're walking back up the chain to fetch it, then + # try and find the states. If we can't get the states, + # discard it. + state_groups = [] + auth_chains = set() + try: + # Get the ones we know about + ours = yield self.store.get_state_groups(pdu.room_id, list(seen)) + state_groups.append(ours) - if fetch_state: - # We need to get the state at this event, since we haven't - # processed all the prev events. - logger.debug( - "_handle_new_pdu getting state for %s", - pdu.room_id - ) - try: - state, auth_chain = yield self.replication_layer.get_state_for_room( - origin, pdu.room_id, pdu.event_id, - ) - except Exception: - logger.exception("Failed to get state for event: %s", pdu.event_id) + for p in prevs - seen: + state, auth_chain = yield self.replication_layer.get_state_for_room( + origin, pdu.room_id, p + ) + auth_chains.update(auth_chain) + state_group = { + (x.type, x.state_key): x.event_id for x in state + } + state_groups.append(state_group) + + def fetch(ev_ids): + return self.store.get_events( + ev_ids, get_prev_content=False, check_redacted=False, + ) + + state = yield resolve_events_with_factory(state_groups, {pdu.event_id: pdu}, fetch) + + state = yield self.store.get_events(state.values()) + state = state.values() + except Exception: + raise FederationError( + "ERROR", + 403, + "We can't get valid state history.", + affected=pdu.event_id, + ) yield self._process_received_pdu( origin, @@ -322,11 +353,17 @@ class FederationHandler(BaseHandler): for e in missing_events: logger.info("Handling found event %s", e.event_id) - yield self.on_receive_pdu( - origin, - e, - get_missing=False - ) + try: + yield self.on_receive_pdu( + origin, + e, + get_missing=False + ) + except FederationError as e: + if e.code == 403: + logger.warn("Event %s failed history check.") + else: + raise @log_function @defer.inlineCallbacks -- cgit 1.4.1 From a7ecf34b70b215f1402ce545e1f6a7c163f8ac28 Mon Sep 17 00:00:00 2001 From: Amber Brown Date: Wed, 27 Jun 2018 11:36:03 +0100 Subject: cleanups --- synapse/handlers/federation.py | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) (limited to 'synapse/handlers/federation.py') diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index 250a5509d8..e9c5d1026a 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -240,35 +240,37 @@ class FederationHandler(BaseHandler): affected=pdu.event_id, ) elif prevs - seen: - # If we're walking back up the chain to fetch it, then - # try and find the states. If we can't get the states, - # discard it. + # Calculate the state of the previous events, and + # de-conflict them to find the current state. state_groups = [] auth_chains = set() try: - # Get the ones we know about + # Get the state of the events we know about ours = yield self.store.get_state_groups(pdu.room_id, list(seen)) state_groups.append(ours) + # Ask the remote server for the states we don't + # know about for p in prevs - seen: - state, auth_chain = yield self.replication_layer.get_state_for_room( + state, got_auth_chain = yield self.replication_layer.get_state_for_room( origin, pdu.room_id, p ) - auth_chains.update(auth_chain) - state_group = { - (x.type, x.state_key): x.event_id for x in state - } + auth_chains.update(got_auth_chain) + state_group = {(x.type, x.state_key): x.event_id for x in state} state_groups.append(state_group) + # Resolve any conflicting state def fetch(ev_ids): return self.store.get_events( - ev_ids, get_prev_content=False, check_redacted=False, + ev_ids, get_prev_content=False, check_redacted=False ) - state = yield resolve_events_with_factory(state_groups, {pdu.event_id: pdu}, fetch) + state_map = yield resolve_events_with_factory( + state_groups, {pdu.event_id: pdu}, fetch + ) - state = yield self.store.get_events(state.values()) - state = state.values() + state = (yield self.store.get_events(state_map.values())).values() + auth_chain = list(auth_chains) except Exception: raise FederationError( "ERROR", -- cgit 1.4.1 From f03a5d1a1759221bd94d75604f3e4e787cd4133e Mon Sep 17 00:00:00 2001 From: Amber Brown Date: Wed, 27 Jun 2018 11:38:14 +0100 Subject: pep8 --- synapse/handlers/federation.py | 10 ++++------ tests/test_federation.py | 7 ++----- 2 files changed, 6 insertions(+), 11 deletions(-) (limited to 'synapse/handlers/federation.py') diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index e9c5d1026a..c4d96749a3 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -169,11 +169,8 @@ class FederationHandler(BaseHandler): defer.returnValue(None) state = None - auth_chain = [] - fetch_state = False - # Get missing pdus if necessary. if not pdu.internal_metadata.is_outlier(): # We only backfill backwards to the min depth. @@ -252,9 +249,10 @@ class FederationHandler(BaseHandler): # Ask the remote server for the states we don't # know about for p in prevs - seen: - state, got_auth_chain = yield self.replication_layer.get_state_for_room( - origin, pdu.room_id, p - ) + state, got_auth_chain = ( + yield self.replication_layer.get_state_for_room( + origin, pdu.room_id, p + )) auth_chains.update(got_auth_chain) state_group = {(x.type, x.state_key): x.event_id for x in state} state_groups.append(state_group) diff --git a/tests/test_federation.py b/tests/test_federation.py index 95fa73723c..fc80a69369 100644 --- a/tests/test_federation.py +++ b/tests/test_federation.py @@ -1,18 +1,15 @@ -from twisted.internet.defer import Deferred, succeed, maybeDeferred +from twisted.internet.defer import succeed, maybeDeferred from synapse.util import Clock from synapse.events import FrozenEvent from synapse.types import Requester, UserID -from synapse.replication.slave.storage.events import SlavedEventStore from tests import unittest -from tests.server import make_request, setup_test_homeserver, ThreadedMemoryReactorClock +from tests.server import setup_test_homeserver, ThreadedMemoryReactorClock from mock import Mock -from synapse.api.errors import CodeMessageException, HttpResponseException - class MessageAcceptTests(unittest.TestCase): def setUp(self): -- cgit 1.4.1 From 99800de63ddec41125c6e1c779c33f96f1cad848 Mon Sep 17 00:00:00 2001 From: Amber Brown Date: Wed, 27 Jun 2018 11:40:27 +0100 Subject: try and clean up --- synapse/handlers/federation.py | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'synapse/handlers/federation.py') diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index c4d96749a3..13117d70fe 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -232,8 +232,10 @@ class FederationHandler(BaseHandler): raise FederationError( "ERROR", 403, - ("Your server isn't divulging details about prev_events " - "referenced in this event."), + ( + "Your server isn't divulging details about prev_events " + "referenced in this event." + ), affected=pdu.event_id, ) elif prevs - seen: @@ -252,7 +254,8 @@ class FederationHandler(BaseHandler): state, got_auth_chain = ( yield self.replication_layer.get_state_for_room( origin, pdu.room_id, p - )) + ) + ) auth_chains.update(got_auth_chain) state_group = {(x.type, x.state_key): x.event_id for x in state} state_groups.append(state_group) -- cgit 1.4.1