From 19a17068f1bc98a1556ff618b544b5fbf57eeba0 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Mon, 6 Aug 2018 15:15:19 +0100 Subject: [PATCH] Check m.room.create for sane room_versions --- synapse/event_auth.py | 10 +++++++++- synapse/federation/federation_client.py | 26 ++++++++++++++++++++++--- 2 files changed, 32 insertions(+), 4 deletions(-) diff --git a/synapse/event_auth.py b/synapse/event_auth.py index b32f64e72..6baeccca3 100644 --- a/synapse/event_auth.py +++ b/synapse/event_auth.py @@ -20,7 +20,7 @@ from signedjson.key import decode_verify_key_bytes from signedjson.sign import SignatureVerifyException, verify_signed_json from unpaddedbase64 import decode_base64 -from synapse.api.constants import EventTypes, JoinRules, Membership +from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventTypes, JoinRules, Membership from synapse.api.errors import AuthError, EventSizeError, SynapseError from synapse.types import UserID, get_domain_from_id @@ -83,6 +83,14 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True): 403, "Creation event's room_id domain does not match sender's" ) + + room_version = event.content.get("room_version", "1") + if room_version not in KNOWN_ROOM_VERSIONS: + raise AuthError( + 403, + "room appears to have unsupported version %s" % ( + room_version, + )) # FIXME logger.debug("Allowing! %s", event) return diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index 7ec1d7a88..c9f3c2d35 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -25,7 +25,7 @@ from prometheus_client import Counter from twisted.internet import defer -from synapse.api.constants import Membership +from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventTypes, Membership from synapse.api.errors import ( CodeMessageException, FederationDeniedError, @@ -518,7 +518,7 @@ class FederationClient(FederationBase): description, destination, exc_info=1, ) - raise RuntimeError("Failed to %s via any server", description) + raise RuntimeError("Failed to %s via any server" % (description, )) def make_membership_event(self, destinations, room_id, user_id, membership, content, params): @@ -609,6 +609,26 @@ class FederationClient(FederationBase): Fails with a ``RuntimeError`` if no servers were reachable. """ + def check_authchain_validity(signed_auth_chain): + for e in signed_auth_chain: + if e.type == EventTypes.Create: + create_event = e + break + else: + raise InvalidResponseError( + "no %s in auth chain" % (EventTypes.Create,), + ) + + # the room version should be sane. + room_version = create_event.content.get("room_version", "1") + if room_version not in KNOWN_ROOM_VERSIONS: + # This shouldn't be possible, because the remote server should have + # rejected the join attempt during make_join. + raise InvalidResponseError( + "room appears to have unsupported version %s" % ( + room_version, + )) + @defer.inlineCallbacks def send_request(destination): time_now = self._clock.time_msec() @@ -665,7 +685,7 @@ class FederationClient(FederationBase): for s in signed_state: s.internal_metadata = copy.deepcopy(s.internal_metadata) - auth_chain.sort(key=lambda e: e.depth) + check_authchain_validity(signed_auth) defer.returnValue({ "state": signed_state,