diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index 65ee1452ce..0c0d678562 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -20,7 +20,7 @@ from twisted.internet import defer
from synapse.api.constants import EventTypes, Membership, JoinRules
from synapse.api.errors import AuthError, Codes, SynapseError
from synapse.util.logutils import log_function
-from synapse.types import UserID
+from synapse.types import UserID, EventID
import logging
@@ -91,7 +91,7 @@ class Auth(object):
self._check_power_levels(event, auth_events)
if event.type == EventTypes.Redaction:
- self._check_redaction(event, auth_events)
+ self.check_redaction(event, auth_events)
logger.debug("Allowing! %s", event)
except AuthError as e:
@@ -541,16 +541,35 @@ class Auth(object):
return True
- def _check_redaction(self, event, auth_events):
+ def check_redaction(self, event, auth_events):
+ """Check whether the event sender is allowed to redact the target event.
+
+ Returns:
+ True if the the sender is allowed to redact the target event if the
+ target event was created by them.
+ False if the sender is allowed to redact the target event with no
+ further checks.
+
+ Raises:
+ AuthError if the event sender is definitely not allowed to redact
+ the target event.
+ """
user_level = self._get_user_power_level(event.user_id, auth_events)
redact_level = self._get_named_level(auth_events, "redact", 50)
- if user_level < redact_level:
- raise AuthError(
- 403,
- "You don't have permission to redact events"
- )
+ if user_level > redact_level:
+ return False
+
+ redacter_domain = EventID.from_string(event.event_id).domain
+ redactee_domain = EventID.from_string(event.redacts).domain
+ if redacter_domain == redactee_domain:
+ return True
+
+ raise AuthError(
+ 403,
+ "You don't have permission to redact events"
+ )
def _check_power_levels(self, event, auth_events):
user_list = event.content.get("users", {})
diff --git a/synapse/handlers/_base.py b/synapse/handlers/_base.py
index cb992143f5..60ac6617ae 100644
--- a/synapse/handlers/_base.py
+++ b/synapse/handlers/_base.py
@@ -15,7 +15,7 @@
from twisted.internet import defer
-from synapse.api.errors import LimitExceededError, SynapseError
+from synapse.api.errors import LimitExceededError, SynapseError, AuthError
from synapse.crypto.event_signing import add_hashes_and_signatures
from synapse.api.constants import Membership, EventTypes
from synapse.types import UserID, RoomAlias
@@ -146,6 +146,21 @@ class BaseHandler(object):
returned_invite.signatures
)
+ if event.type == EventTypes.Redaction:
+ if self.auth.check_redaction(event, auth_events=context.current_state):
+ original_event = yield self.store.get_event(
+ event.redacts,
+ check_redacted=False,
+ get_prev_content=False,
+ allow_rejected=False,
+ allow_none=False
+ )
+ if event.user_id != original_event.user_id:
+ raise AuthError(
+ 403,
+ "You don't have permission to redact events"
+ )
+
destinations = set(extra_destinations)
for k, s in context.current_state.items():
try:
|
