From 49d3bca37b91fa092e13fd28c42dcf970fb86bb7 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Mon, 27 Jan 2020 16:14:54 +0000 Subject: [PATCH] Implement updated auth rules from MSC2260 --- synapse/api/room_versions.py | 16 ++++++++++++++++ synapse/event_auth.py | 24 +++++++++++++++++++----- 2 files changed, 35 insertions(+), 5 deletions(-) diff --git a/synapse/api/room_versions.py b/synapse/api/room_versions.py index c6f50fd7b..cf7ee60d3 100644 --- a/synapse/api/room_versions.py +++ b/synapse/api/room_versions.py @@ -57,6 +57,9 @@ class RoomVersion(object): state_res = attr.ib() # int; one of the StateResolutionVersions enforce_key_validity = attr.ib() # bool + # bool: before MSC2260, anyone was allowed to send an aliases event + special_case_aliases_auth = attr.ib(type=bool, default=False) + class RoomVersions(object): V1 = RoomVersion( @@ -65,6 +68,7 @@ class RoomVersions(object): EventFormatVersions.V1, StateResolutionVersions.V1, enforce_key_validity=False, + special_case_aliases_auth=True, ) V2 = RoomVersion( "2", @@ -72,6 +76,7 @@ class RoomVersions(object): EventFormatVersions.V1, StateResolutionVersions.V2, enforce_key_validity=False, + special_case_aliases_auth=True, ) V3 = RoomVersion( "3", @@ -79,6 +84,7 @@ class RoomVersions(object): EventFormatVersions.V2, StateResolutionVersions.V2, enforce_key_validity=False, + special_case_aliases_auth=True, ) V4 = RoomVersion( "4", @@ -86,6 +92,7 @@ class RoomVersions(object): EventFormatVersions.V3, StateResolutionVersions.V2, enforce_key_validity=False, + special_case_aliases_auth=True, ) V5 = RoomVersion( "5", @@ -93,6 +100,14 @@ class RoomVersions(object): EventFormatVersions.V3, StateResolutionVersions.V2, enforce_key_validity=True, + special_case_aliases_auth=True, + ) + MSC2260_DEV = RoomVersion( + "org.matrix.msc2260", + RoomDisposition.UNSTABLE, + EventFormatVersions.V3, + StateResolutionVersions.V2, + enforce_key_validity=True, ) @@ -104,5 +119,6 @@ KNOWN_ROOM_VERSIONS = { RoomVersions.V3, RoomVersions.V4, RoomVersions.V5, + RoomVersions.MSC2260_DEV, ) } # type: Dict[str, RoomVersion] diff --git a/synapse/event_auth.py b/synapse/event_auth.py index 016d5678e..3240e8a7b 100644 --- a/synapse/event_auth.py +++ b/synapse/event_auth.py @@ -100,7 +100,12 @@ def check( if not event.signatures.get(event_id_domain): raise AuthError(403, "Event not signed by sending server") + # Implementation of https://matrix.org/docs/spec/rooms/v1#authorization-rules + # + # 1. If type is m.room.create: if event.type == EventTypes.Create: + # 1b. If the domain of the room_id does not match the domain of the sender, + # reject. sender_domain = get_domain_from_id(event.sender) room_id_domain = get_domain_from_id(event.room_id) if room_id_domain != sender_domain: @@ -108,40 +113,49 @@ def check( 403, "Creation event's room_id domain does not match sender's" ) + # 1c. If content.room_version is present and is not a recognised version, reject room_version_prop = event.content.get("room_version", "1") if room_version_prop not in KNOWN_ROOM_VERSIONS: raise AuthError( 403, "room appears to have unsupported version %s" % (room_version_prop,), ) - # FIXME + logger.debug("Allowing! %s", event) return + # 3. If event does not have a m.room.create in its auth_events, reject. creation_event = auth_events.get((EventTypes.Create, ""), None) - if not creation_event: raise AuthError(403, "No create event in auth events") + # additional check for m.federate creating_domain = get_domain_from_id(event.room_id) originating_domain = get_domain_from_id(event.sender) if creating_domain != originating_domain: if not _can_federate(event, auth_events): raise AuthError(403, "This room has been marked as unfederatable.") - # FIXME: Temp hack + # 4. If type is m.room.aliases if event.type == EventTypes.Aliases: + # 4a. If event has no state_key, reject if not event.is_state(): raise AuthError(403, "Alias event must be a state event") if not event.state_key: raise AuthError(403, "Alias event must have non-empty state_key") + + # 4b. If sender's domain doesn't matches [sic] state_key, reject sender_domain = get_domain_from_id(event.sender) if event.state_key != sender_domain: raise AuthError( 403, "Alias event's state_key does not match sender's domain" ) - logger.debug("Allowing! %s", event) - return + + # 4c. Otherwise, allow. + # This is removed by https://github.com/matrix-org/matrix-doc/pull/2260 + if room_version.special_case_aliases_auth: + logger.debug("Allowing! %s", event) + return if logger.isEnabledFor(logging.DEBUG): logger.debug("Auth events: %s", [a.event_id for a in auth_events.values()])