diff options
Diffstat (limited to 'synapse/federation/federation_base.py')
| -rw-r--r-- | synapse/federation/federation_base.py | 89 |
1 files changed, 42 insertions, 47 deletions
diff --git a/synapse/federation/federation_base.py b/synapse/federation/federation_base.py index 7bc54b9988..a6232e048b 100644 --- a/synapse/federation/federation_base.py +++ b/synapse/federation/federation_base.py @@ -32,6 +32,18 @@ if TYPE_CHECKING: logger = logging.getLogger(__name__) +class InvalidEventSignatureError(RuntimeError): + """Raised when the signature on an event is invalid. + + The stringification of this exception is just the error message without reference + to the event id. The event id is available as a property. + """ + + def __init__(self, message: str, event_id: str): + super().__init__(message) + self.event_id = event_id + + class FederationBase: def __init__(self, hs: "HomeServer"): self.hs = hs @@ -59,20 +71,13 @@ class FederationBase: Returns: * the original event if the checks pass * a redacted version of the event (if the signature - matched but the hash did not) + matched but the hash did not). In this case a warning will be logged. Raises: - SynapseError if the signature check failed. + InvalidEventSignatureError if the signature check failed. Nothing + will be logged in this case. """ - try: - await _check_sigs_on_pdu(self.keyring, room_version, pdu) - except SynapseError as e: - logger.warning( - "Signature check failed for %s: %s", - pdu.event_id, - e, - ) - raise + await _check_sigs_on_pdu(self.keyring, room_version, pdu) if not check_event_content_hash(pdu): # let's try to distinguish between failures because the event was @@ -87,7 +92,7 @@ class FederationBase: if set(redacted_event.keys()) == set(pdu.keys()) and set( redacted_event.content.keys() ) == set(pdu.content.keys()): - logger.info( + logger.debug( "Event %s seems to have been redacted; using our redacted copy", pdu.event_id, ) @@ -116,12 +121,13 @@ async def _check_sigs_on_pdu( ) -> None: """Check that the given events are correctly signed - Raise a SynapseError if the event wasn't correctly signed. - Args: keyring: keyring object to do the checks room_version: the room version of the PDUs pdus: the events to be checked + + Raises: + InvalidEventSignatureError if the event wasn't correctly signed. """ # we want to check that the event is signed by: @@ -147,44 +153,38 @@ async def _check_sigs_on_pdu( # 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) + sender_domain = get_domain_from_id(pdu.sender) if not _is_invite_via_3pid(pdu): try: await keyring.verify_event_for_server( - get_domain_from_id(pdu.sender), + sender_domain, pdu, pdu.origin_server_ts if room_version.enforce_key_validity else 0, ) except Exception as e: - errmsg = "event id %s: unable to verify signature for sender %s: %s" % ( + raise InvalidEventSignatureError( + f"unable to verify signature for sender domain {sender_domain}: {e}", pdu.event_id, - get_domain_from_id(pdu.sender), - e, - ) - raise SynapseError(403, errmsg, Codes.FORBIDDEN) + ) from None # 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 # (ie, the room version uses old-style non-hash event IDs). - if room_version.event_format == EventFormatVersions.V1 and get_domain_from_id( - pdu.event_id - ) != get_domain_from_id(pdu.sender): - try: - await keyring.verify_event_for_server( - get_domain_from_id(pdu.event_id), - pdu, - pdu.origin_server_ts if room_version.enforce_key_validity else 0, - ) - except Exception as e: - errmsg = ( - "event id %s: unable to verify signature for event id domain %s: %s" - % ( - pdu.event_id, - get_domain_from_id(pdu.event_id), - e, + if room_version.event_format == EventFormatVersions.V1: + event_domain = get_domain_from_id(pdu.event_id) + if event_domain != sender_domain: + try: + await keyring.verify_event_for_server( + event_domain, + pdu, + pdu.origin_server_ts if room_version.enforce_key_validity else 0, ) - ) - raise SynapseError(403, errmsg, Codes.FORBIDDEN) + except Exception as e: + raise InvalidEventSignatureError( + f"unable to verify signature for event domain {event_domain}: {e}", + pdu.event_id, + ) from None # If this is a join event for a restricted room it may have been authorised # via a different server from the sending server. Check those signatures. @@ -204,15 +204,10 @@ async def _check_sigs_on_pdu( pdu.origin_server_ts if room_version.enforce_key_validity else 0, ) except Exception as e: - errmsg = ( - "event id %s: unable to verify signature for authorising server %s: %s" - % ( - pdu.event_id, - authorising_server, - e, - ) - ) - raise SynapseError(403, errmsg, Codes.FORBIDDEN) + raise InvalidEventSignatureError( + f"unable to verify signature for authorising serve {authorising_server}: {e}", + pdu.event_id, + ) from None def _is_invite_via_3pid(event: EventBase) -> bool: |