Delete devices in various logout situations

Make sure that we delete devices whenever a user is logged out due to any of
the following situations:

 * /logout
 * /logout_all
 * change password
 * deactivate account (by the user or by an admin)
 * invalidate access token from a dynamic module

Fixes #2672.

synapse/handlers/deactivate_account.py

@@ -26,6 +26,7 @@ class DeactivateAccountHandler(BaseHandler):
     def __init__(self, hs):
         super(DeactivateAccountHandler, self).__init__(hs)
         self._auth_handler = hs.get_auth_handler()
+        self._device_handler = hs.get_device_handler()
 
     @defer.inlineCallbacks
     def deactivate_account(self, user_id):
@@ -39,6 +40,13 @@ class DeactivateAccountHandler(BaseHandler):
         """
         # FIXME: Theoretically there is a race here wherein user resets
         # password using threepid.
+
+        # first delete any devices belonging to the user, which will also
+        # delete corresponding access tokens.
+        yield self._device_handler.delete_all_devices_for_user(user_id)
+        # then delete any remaining access tokens which weren't associated with
+        # a device.
         yield self._auth_handler.delete_access_tokens_for_user(user_id)
+
         yield self.store.user_delete_threepids(user_id)
         yield self.store.user_set_password_hash(user_id, None)

synapse/handlers/device.py

@@ -170,13 +170,31 @@ class DeviceHandler(BaseHandler):
 
         yield self.notify_device_update(user_id, [device_id])
 
+    @defer.inlineCallbacks
+    def delete_all_devices_for_user(self, user_id, except_device_id=None):
+        """Delete all of the user's devices
+
+        Args:
+            user_id (str):
+            except_device_id (str|None): optional device id which should not
+                be deleted
+
+        Returns:
+            defer.Deferred:
+        """
+        device_map = yield self.store.get_devices_by_user(user_id)
+        device_ids = device_map.keys()
+        if except_device_id is not None:
+            device_ids = [d for d in device_ids if d != except_device_id]
+        yield self.delete_devices(user_id, device_ids)
+
     @defer.inlineCallbacks
     def delete_devices(self, user_id, device_ids):
         """ Delete several devices
 
         Args:
             user_id (str):
-            device_ids (str): The list of device IDs to delete
+            device_ids (List[str]): The list of device IDs to delete
 
         Returns:
             defer.Deferred:

synapse/handlers/set_password.py

@@ -27,11 +27,13 @@ class SetPasswordHandler(BaseHandler):
     def __init__(self, hs):
         super(SetPasswordHandler, self).__init__(hs)
         self._auth_handler = hs.get_auth_handler()
+        self._device_handler = hs.get_device_handler()
 
     @defer.inlineCallbacks
     def set_password(self, user_id, newpassword, requester=None):
         password_hash = self._auth_handler.hash(newpassword)
 
+        except_device_id = requester.device_id if requester else None
         except_access_token_id = requester.access_token_id if requester else None
 
         try:
@@ -40,6 +42,15 @@ class SetPasswordHandler(BaseHandler):
             if e.code == 404:
                 raise SynapseError(404, "Unknown user", Codes.NOT_FOUND)
             raise e
+
+        # we want to log out all of the user's other sessions. First delete
+        # all his other devices.
+        yield self._device_handler.delete_all_devices_for_user(
+            user_id, except_device_id=except_device_id,
+        )
+
+        # and now delete any access tokens which weren't associated with
+        # devices (or were associated with this device).
         yield self._auth_handler.delete_access_tokens_for_user(
             user_id, except_token_id=except_access_token_id,
         )