Do not propagate typing notifications from shadow-banned users. (#8176)

1 files changed, 16 insertions, 5 deletions

diff --git a/synapse/handlers/typing.py b/synapse/handlers/typing.py
index a86ac0150e..1d828bd7be 100644
--- a/synapse/handlers/typing.py
+++ b/synapse/handlers/typing.py
@@ -14,10 +14,11 @@
 # limitations under the License.
 
 import logging
+import random
 from collections import namedtuple
 from typing import TYPE_CHECKING, List, Set, Tuple
 
-from synapse.api.errors import AuthError, SynapseError
+from synapse.api.errors import AuthError, ShadowBanError, SynapseError
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.replication.tcp.streams import TypingStream
 from synapse.types import UserID, get_domain_from_id
@@ -227,9 +228,9 @@ class TypingWriterHandler(FollowerTypingHandler):
             self._stopped_typing(member)
             return
 
-    async def started_typing(self, target_user, auth_user, room_id, timeout):
+    async def started_typing(self, target_user, requester, room_id, timeout):
         target_user_id = target_user.to_string()
-        auth_user_id = auth_user.to_string()
+        auth_user_id = requester.user.to_string()
 
         if not self.is_mine_id(target_user_id):
             raise SynapseError(400, "User is not hosted on this homeserver")
@@ -237,6 +238,11 @@ class TypingWriterHandler(FollowerTypingHandler):
         if target_user_id != auth_user_id:
             raise AuthError(400, "Cannot set another user's typing state")
 
+        if requester.shadow_banned:
+            # We randomly sleep a bit just to annoy the requester.
+            await self.clock.sleep(random.randint(1, 10))
+            raise ShadowBanError()
+
         await self.auth.check_user_in_room(room_id, target_user_id)
 
         logger.debug("%s has started typing in %s", target_user_id, room_id)
@@ -256,9 +262,9 @@ class TypingWriterHandler(FollowerTypingHandler):
 
         self._push_update(member=member, typing=True)
 
-    async def stopped_typing(self, target_user, auth_user, room_id):
+    async def stopped_typing(self, target_user, requester, room_id):
         target_user_id = target_user.to_string()
-        auth_user_id = auth_user.to_string()
+        auth_user_id = requester.user.to_string()
 
         if not self.is_mine_id(target_user_id):
             raise SynapseError(400, "User is not hosted on this homeserver")
@@ -266,6 +272,11 @@ class TypingWriterHandler(FollowerTypingHandler):
         if target_user_id != auth_user_id:
             raise AuthError(400, "Cannot set another user's typing state")
 
+        if requester.shadow_banned:
+            # We randomly sleep a bit just to annoy the requester.
+            await self.clock.sleep(random.randint(1, 10))
+            raise ShadowBanError()
+
         await self.auth.check_user_in_room(room_id, target_user_id)
 
         logger.debug("%s has stopped typing in %s", target_user_id, room_id)