diff options
| -rw-r--r-- | changelog.d/11033.bugfix | 1 | ||||
| -rw-r--r-- | docs/modules/third_party_rules_callbacks.md | 8 | ||||
| -rw-r--r-- | synapse/api/errors.py | 7 | ||||
| -rw-r--r-- | synapse/events/third_party_rules.py | 9 | ||||
| -rw-r--r-- | tests/rest/client/test_third_party_rules.py | 16 |
5 files changed, 24 insertions, 17 deletions
diff --git a/changelog.d/11033.bugfix b/changelog.d/11033.bugfix new file mode 100644 index 0000000000..fa99f187b8 --- /dev/null +++ b/changelog.d/11033.bugfix @@ -0,0 +1 @@ +Do not accept events if a third-party rule module API callback raises an exception. diff --git a/docs/modules/third_party_rules_callbacks.md b/docs/modules/third_party_rules_callbacks.md index a16e272f79..a3a17096a8 100644 --- a/docs/modules/third_party_rules_callbacks.md +++ b/docs/modules/third_party_rules_callbacks.md @@ -43,6 +43,14 @@ event with new data by returning the new event's data as a dictionary. In order that, it is recommended the module calls `event.get_dict()` to get the current event as a dictionary, and modify the returned dictionary accordingly. +If `check_event_allowed` raises an exception, the module is assumed to have failed. +The event will not be accepted but is not treated as explicitly rejected, either. +An HTTP request causing the module check will likely result in a 500 Internal +Server Error. + +When the boolean returned by the module is `False`, the event is rejected. +(Module developers should not use exceptions for rejection.) + Note that replacing the event only works for events sent by local users, not for events received over federation. diff --git a/synapse/api/errors.py b/synapse/api/errors.py index 685d1c25cf..85302163da 100644 --- a/synapse/api/errors.py +++ b/synapse/api/errors.py @@ -596,3 +596,10 @@ class ShadowBanError(Exception): This should be caught and a proper "fake" success response sent to the user. """ + + +class ModuleFailedException(Exception): + """ + Raised when a module API callback fails, for example because it raised an + exception. + """ diff --git a/synapse/events/third_party_rules.py b/synapse/events/third_party_rules.py index 8816ef4b76..1bb8ca7145 100644 --- a/synapse/events/third_party_rules.py +++ b/synapse/events/third_party_rules.py @@ -14,7 +14,7 @@ import logging from typing import TYPE_CHECKING, Any, Awaitable, Callable, List, Optional, Tuple -from synapse.api.errors import SynapseError +from synapse.api.errors import ModuleFailedException, SynapseError from synapse.events import EventBase from synapse.events.snapshot import EventContext from synapse.types import Requester, StateMap @@ -233,9 +233,10 @@ class ThirdPartyEventRules: # This module callback needs a rework so that hacks such as # this one are not necessary. raise e - except Exception as e: - logger.warning("Failed to run module API callback %s: %s", callback, e) - continue + except Exception: + raise ModuleFailedException( + "Failed to run `check_event_allowed` module API callback" + ) # Return if the event shouldn't be allowed or if the module came up with a # replacement dict for the event. diff --git a/tests/rest/client/test_third_party_rules.py b/tests/rest/client/test_third_party_rules.py index 1c42c46630..4e71b6ec12 100644 --- a/tests/rest/client/test_third_party_rules.py +++ b/tests/rest/client/test_third_party_rules.py @@ -216,19 +216,9 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase): {"x": "x"}, access_token=self.tok, ) - # check_event_allowed has some error handling, so it shouldn't 500 just because a - # module did something bad. - self.assertEqual(channel.code, 200, channel.result) - event_id = channel.json_body["event_id"] - - channel = self.make_request( - "GET", - "/_matrix/client/r0/rooms/%s/event/%s" % (self.room_id, event_id), - access_token=self.tok, - ) - self.assertEqual(channel.code, 200, channel.result) - ev = channel.json_body - self.assertEqual(ev["content"]["x"], "x") + # Because check_event_allowed raises an exception, it leads to a + # 500 Internal Server Error + self.assertEqual(channel.code, 500, channel.result) def test_modify_event(self): """The module can return a modified version of the event""" |