diff options
| -rw-r--r-- | synapse/api/auth.py | 35 | ||||
| -rw-r--r-- | synapse/handlers/_base.py | 17 |
2 files changed, 43 insertions, 9 deletions
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: |