diff --git a/changelog.d/7502.feature b/changelog.d/7502.feature
new file mode 100644
index 0000000000..059a05bfca
--- /dev/null
+++ b/changelog.d/7502.feature
@@ -0,0 +1 @@
+Add additional authentication checks for m.room.power_levels event per [MSC2209](https://github.com/matrix-org/matrix-doc/pull/2209).
diff --git a/synapse/api/room_versions.py b/synapse/api/room_versions.py
index 871179749a..af3612ed61 100644
--- a/synapse/api/room_versions.py
+++ b/synapse/api/room_versions.py
@@ -58,7 +58,11 @@ class RoomVersion(object):
enforce_key_validity = attr.ib() # bool
# bool: before MSC2261/MSC2432, m.room.aliases had special auth rules and redaction rules
- special_case_aliases_auth = attr.ib(type=bool, default=False)
+ special_case_aliases_auth = attr.ib(type=bool)
+
+ # bool: MSC2209: Check 'notifications' key while verifying
+ # m.room.power_levels auth rules.
+ limit_notifications_power_levels = attr.ib(type=bool)
class RoomVersions(object):
@@ -69,6 +73,7 @@ class RoomVersions(object):
StateResolutionVersions.V1,
enforce_key_validity=False,
special_case_aliases_auth=True,
+ limit_notifications_power_levels=False,
)
V2 = RoomVersion(
"2",
@@ -77,6 +82,7 @@ class RoomVersions(object):
StateResolutionVersions.V2,
enforce_key_validity=False,
special_case_aliases_auth=True,
+ limit_notifications_power_levels=False,
)
V3 = RoomVersion(
"3",
@@ -85,6 +91,7 @@ class RoomVersions(object):
StateResolutionVersions.V2,
enforce_key_validity=False,
special_case_aliases_auth=True,
+ limit_notifications_power_levels=False,
)
V4 = RoomVersion(
"4",
@@ -93,6 +100,7 @@ class RoomVersions(object):
StateResolutionVersions.V2,
enforce_key_validity=False,
special_case_aliases_auth=True,
+ limit_notifications_power_levels=False,
)
V5 = RoomVersion(
"5",
@@ -101,6 +109,7 @@ class RoomVersions(object):
StateResolutionVersions.V2,
enforce_key_validity=True,
special_case_aliases_auth=True,
+ limit_notifications_power_levels=False,
)
MSC2432_DEV = RoomVersion(
"org.matrix.msc2432",
@@ -109,6 +118,16 @@ class RoomVersions(object):
StateResolutionVersions.V2,
enforce_key_validity=True,
special_case_aliases_auth=False,
+ limit_notifications_power_levels=False,
+ )
+ MSC2209_DEV = RoomVersion(
+ "org.matrix.msc2209",
+ RoomDisposition.UNSTABLE,
+ EventFormatVersions.V3,
+ StateResolutionVersions.V2,
+ enforce_key_validity=True,
+ special_case_aliases_auth=True,
+ limit_notifications_power_levels=True,
)
@@ -121,5 +140,6 @@ KNOWN_ROOM_VERSIONS = {
RoomVersions.V4,
RoomVersions.V5,
RoomVersions.MSC2432_DEV,
+ RoomVersions.MSC2209_DEV,
)
} # type: Dict[str, RoomVersion]
diff --git a/synapse/event_auth.py b/synapse/event_auth.py
index 46beb5334f..5a5b568a95 100644
--- a/synapse/event_auth.py
+++ b/synapse/event_auth.py
@@ -181,7 +181,7 @@ def check(
_can_send_event(event, auth_events)
if event.type == EventTypes.PowerLevels:
- _check_power_levels(event, auth_events)
+ _check_power_levels(room_version_obj, event, auth_events)
if event.type == EventTypes.Redaction:
check_redaction(room_version_obj, event, auth_events)
@@ -442,7 +442,7 @@ def check_redaction(room_version_obj: RoomVersion, event, auth_events):
raise AuthError(403, "You don't have permission to redact events")
-def _check_power_levels(event, auth_events):
+def _check_power_levels(room_version_obj, event, auth_events):
user_list = event.content.get("users", {})
# Validate users
for k, v in user_list.items():
@@ -484,6 +484,14 @@ def _check_power_levels(event, auth_events):
for ev_id in set(list(old_list) + list(new_list)):
levels_to_check.append((ev_id, "events"))
+ # MSC2209 specifies these checks should also be done for the "notifications"
+ # key.
+ if room_version_obj.limit_notifications_power_levels:
+ old_list = current_state.content.get("notifications", {})
+ new_list = event.content.get("notifications", {})
+ for ev_id in set(list(old_list) + list(new_list)):
+ levels_to_check.append((ev_id, "notifications"))
+
old_state = current_state.content
new_state = event.content
diff --git a/tests/test_event_auth.py b/tests/test_event_auth.py
index 6c2351cf55..f2def601fb 100644
--- a/tests/test_event_auth.py
+++ b/tests/test_event_auth.py
@@ -165,6 +165,39 @@ class EventAuthTestCase(unittest.TestCase):
do_sig_check=False,
)
+ def test_msc2209(self):
+ """
+ Notifications power levels get checked due to MSC2209.
+ """
+ creator = "@creator:example.com"
+ pleb = "@joiner:example.com"
+
+ auth_events = {
+ ("m.room.create", ""): _create_event(creator),
+ ("m.room.member", creator): _join_event(creator),
+ ("m.room.power_levels", ""): _power_levels_event(
+ creator, {"state_default": "30", "users": {pleb: "30"}}
+ ),
+ ("m.room.member", pleb): _join_event(pleb),
+ }
+
+ # pleb should be able to modify the notifications power level.
+ event_auth.check(
+ RoomVersions.V1,
+ _power_levels_event(pleb, {"notifications": {"room": 100}}),
+ auth_events,
+ do_sig_check=False,
+ )
+
+ # But an MSC2209 room rejects this change.
+ with self.assertRaises(AuthError):
+ event_auth.check(
+ RoomVersions.MSC2209_DEV,
+ _power_levels_event(pleb, {"notifications": {"room": 100}}),
+ auth_events,
+ do_sig_check=False,
+ )
+
# helpers for making events
|
