2 files changed, 30 insertions, 15 deletions
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index 6720c6a728..21cdd6cdbe 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -258,20 +258,29 @@ class MessageHandler(BaseHandler):
 
     @defer.inlineCallbacks
     def _check_in_room_or_world_readable(self, room_id, user_id, is_guest):
-        if is_guest:
-            visibility = yield self.state_handler.get_current_state(
-                room_id, EventTypes.RoomHistoryVisibility, ""
-            )
-            if visibility.content["history_visibility"] == "world_readable":
-                defer.returnValue((Membership.JOIN, None))
-                return
-            else:
-                raise AuthError(
-                    403, "Guest access not allowed", errcode=Codes.GUEST_ACCESS_FORBIDDEN
-                )
-        else:
+        try:
+            # check_user_was_in_room will return the most recent membership
+            # event for the user if:
+            #  * The user is a non-guest user, and was ever in the room
+            #  * The user is a guest user, and has joined the room
+            # else it will throw.
             member_event = yield self.auth.check_user_was_in_room(room_id, user_id)
             defer.returnValue((member_event.membership, member_event.event_id))
+            return
+        except AuthError:
+            if not is_guest:
+                raise
+
+        visibility = yield self.state_handler.get_current_state(
+            room_id, EventTypes.RoomHistoryVisibility, ""
+        )
+        if visibility.content["history_visibility"] == "world_readable":
+            defer.returnValue((Membership.JOIN, None))
+            return
+        else:
+            raise AuthError(
+                403, "Guest access not allowed", errcode=Codes.GUEST_ACCESS_FORBIDDEN
+            )
 
     @defer.inlineCallbacks
     def get_state_events(self, user_id, room_id, is_guest=False):
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 7d18218cd9..0266926fc7 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -765,7 +765,7 @@ class RoomListHandler(BaseHandler):
 
 class RoomContextHandler(BaseHandler):
     @defer.inlineCallbacks
-    def get_event_context(self, user, room_id, event_id, limit):
+    def get_event_context(self, user, room_id, event_id, limit, is_guest):
         """Retrieves events, pagination tokens and state around a given event
         in a room.
 
@@ -789,11 +789,17 @@ class RoomContextHandler(BaseHandler):
         )
 
         results["events_before"] = yield self._filter_events_for_client(
-            user.to_string(), results["events_before"]
+            user.to_string(),
+            results["events_before"],
+            is_guest=is_guest,
+            require_all_visible_for_guests=False
         )
 
         results["events_after"] = yield self._filter_events_for_client(
-            user.to_string(), results["events_after"]
+            user.to_string(),
+            results["events_after"],
+            is_guest=is_guest,
+            require_all_visible_for_guests=False
         )
 
         if results["events_after"]: