diff options
Diffstat (limited to 'synapse/federation/federation_base.py')
| -rw-r--r-- | synapse/federation/federation_base.py | 96 |
1 files changed, 59 insertions, 37 deletions
diff --git a/synapse/federation/federation_base.py b/synapse/federation/federation_base.py index b7ad729c63..a7a2ec4523 100644 --- a/synapse/federation/federation_base.py +++ b/synapse/federation/federation_base.py @@ -20,10 +20,10 @@ import six from twisted.internet import defer from twisted.internet.defer import DeferredList -from synapse.api.constants import MAX_DEPTH, EventTypes, Membership +from synapse.api.constants import MAX_DEPTH, EventTypes, Membership, RoomVersions from synapse.api.errors import Codes, SynapseError from synapse.crypto.event_signing import check_event_content_hash -from synapse.events import FrozenEvent +from synapse.events import event_type_from_format_version from synapse.events.utils import prune_event from synapse.http.servlet import assert_params_in_dict from synapse.types import get_domain_from_id @@ -43,8 +43,8 @@ class FederationBase(object): self._clock = hs.get_clock() @defer.inlineCallbacks - def _check_sigs_and_hash_and_fetch(self, origin, pdus, outlier=False, - include_none=False): + def _check_sigs_and_hash_and_fetch(self, origin, pdus, room_version, + outlier=False, include_none=False): """Takes a list of PDUs and checks the signatures and hashs of each one. If a PDU fails its signature check then we check if we have it in the database and if not then request if from the originating server of @@ -56,13 +56,17 @@ class FederationBase(object): a new list. Args: + origin (str) pdu (list) - outlier (bool) + room_version (str) + outlier (bool): Whether the events are outliers or not + include_none (str): Whether to include None in the returned list + for events that have failed their checks Returns: Deferred : A list of PDUs that have valid signatures and hashes. """ - deferreds = self._check_sigs_and_hashes(pdus) + deferreds = self._check_sigs_and_hashes(room_version, pdus) @defer.inlineCallbacks def handle_check_result(pdu, deferred): @@ -84,6 +88,7 @@ class FederationBase(object): res = yield self.get_pdu( destinations=[pdu.origin], event_id=pdu.event_id, + room_version=room_version, outlier=outlier, timeout=10000, ) @@ -116,16 +121,17 @@ class FederationBase(object): else: defer.returnValue([p for p in valid_pdus if p]) - def _check_sigs_and_hash(self, pdu): + def _check_sigs_and_hash(self, room_version, pdu): return logcontext.make_deferred_yieldable( - self._check_sigs_and_hashes([pdu])[0], + self._check_sigs_and_hashes(room_version, [pdu])[0], ) - def _check_sigs_and_hashes(self, pdus): + def _check_sigs_and_hashes(self, room_version, pdus): """Checks that each of the received events is correctly signed by the sending server. Args: + room_version (str): The room version of the PDUs pdus (list[FrozenEvent]): the events to be checked Returns: @@ -136,7 +142,7 @@ class FederationBase(object): * throws a SynapseError if the signature check failed. The deferreds run their callbacks in the sentinel logcontext. """ - deferreds = _check_sigs_on_pdus(self.keyring, pdus) + deferreds = _check_sigs_on_pdus(self.keyring, room_version, pdus) ctx = logcontext.LoggingContext.current_context() @@ -198,16 +204,17 @@ class FederationBase(object): class PduToCheckSig(namedtuple("PduToCheckSig", [ - "pdu", "redacted_pdu_json", "event_id_domain", "sender_domain", "deferreds", + "pdu", "redacted_pdu_json", "sender_domain", "deferreds", ])): pass -def _check_sigs_on_pdus(keyring, pdus): +def _check_sigs_on_pdus(keyring, room_version, pdus): """Check that the given events are correctly signed Args: keyring (synapse.crypto.Keyring): keyring object to do the checks + room_version (str): the room version of the PDUs pdus (Collection[EventBase]): the events to be checked Returns: @@ -220,9 +227,7 @@ def _check_sigs_on_pdus(keyring, pdus): # we want to check that the event is signed by: # - # (a) the server which created the event_id - # - # (b) the sender's server. + # (a) the sender's server # # - except in the case of invites created from a 3pid invite, which are exempt # from this check, because the sender has to match that of the original 3pid @@ -236,34 +241,26 @@ def _check_sigs_on_pdus(keyring, pdus): # and signatures are *supposed* to be valid whether or not an event has been # redacted. But this isn't the worst of the ways that 3pid invites are broken. # + # (b) for V1 and V2 rooms, the server which created the event_id + # # let's start by getting the domain for each pdu, and flattening the event back # to JSON. + pdus_to_check = [ PduToCheckSig( pdu=p, redacted_pdu_json=prune_event(p).get_pdu_json(), - event_id_domain=get_domain_from_id(p.event_id), sender_domain=get_domain_from_id(p.sender), deferreds=[], ) for p in pdus ] - # first make sure that the event is signed by the event_id's domain - deferreds = keyring.verify_json_objects_for_server([ - (p.event_id_domain, p.redacted_pdu_json) - for p in pdus_to_check - ]) - - for p, d in zip(pdus_to_check, deferreds): - p.deferreds.append(d) - - # now let's look for events where the sender's domain is different to the - # event id's domain (normally only the case for joins/leaves), and add additional - # checks. + # First we check that the sender event is signed by the sender's domain + # (except if its a 3pid invite, in which case it may be sent by any server) pdus_to_check_sender = [ p for p in pdus_to_check - if p.sender_domain != p.event_id_domain and not _is_invite_via_3pid(p.pdu) + if not _is_invite_via_3pid(p.pdu) ] more_deferreds = keyring.verify_json_objects_for_server([ @@ -274,19 +271,43 @@ def _check_sigs_on_pdus(keyring, pdus): for p, d in zip(pdus_to_check_sender, more_deferreds): p.deferreds.append(d) + # now let's look for events where the sender's domain is different to the + # event id's domain (normally only the case for joins/leaves), and add additional + # checks. Only do this if the room version has a concept of event ID domain + if room_version in ( + RoomVersions.V1, RoomVersions.V2, RoomVersions.STATE_V2_TEST, + ): + pdus_to_check_event_id = [ + p for p in pdus_to_check + if p.sender_domain != get_domain_from_id(p.pdu.event_id) + ] + + more_deferreds = keyring.verify_json_objects_for_server([ + (get_domain_from_id(p.pdu.event_id), p.redacted_pdu_json) + for p in pdus_to_check_event_id + ]) + + for p, d in zip(pdus_to_check_event_id, more_deferreds): + p.deferreds.append(d) + elif room_version in (RoomVersions.V3,): + pass # No further checks needed, as event IDs are hashes here + else: + raise RuntimeError("Unrecognized room version %s" % (room_version,)) + # replace lists of deferreds with single Deferreds return [_flatten_deferred_list(p.deferreds) for p in pdus_to_check] def _flatten_deferred_list(deferreds): - """Given a list of one or more deferreds, either return the single deferred, or - combine into a DeferredList. + """Given a list of deferreds, either return the single deferred, + combine into a DeferredList, or return an already resolved deferred. """ if len(deferreds) > 1: return DeferredList(deferreds, fireOnOneErrback=True, consumeErrors=True) - else: - assert len(deferreds) == 1 + elif len(deferreds) == 1: return deferreds[0] + else: + return defer.succeed(None) def _is_invite_via_3pid(event): @@ -297,11 +318,12 @@ def _is_invite_via_3pid(event): ) -def event_from_pdu_json(pdu_json, outlier=False): +def event_from_pdu_json(pdu_json, event_format_version, outlier=False): """Construct a FrozenEvent from an event json received over federation Args: pdu_json (object): pdu as received over federation + event_format_version (int): The event format version outlier (bool): True to mark this event as an outlier Returns: @@ -313,7 +335,7 @@ def event_from_pdu_json(pdu_json, outlier=False): """ # we could probably enforce a bunch of other fields here (room_id, sender, # origin, etc etc) - assert_params_in_dict(pdu_json, ('event_id', 'type', 'depth')) + assert_params_in_dict(pdu_json, ('type', 'depth')) depth = pdu_json['depth'] if not isinstance(depth, six.integer_types): @@ -325,8 +347,8 @@ def event_from_pdu_json(pdu_json, outlier=False): elif depth > MAX_DEPTH: raise SynapseError(400, "Depth too large", Codes.BAD_JSON) - event = FrozenEvent( - pdu_json + event = event_type_from_format_version(event_format_version)( + pdu_json, ) event.internal_metadata.outlier = outlier |