Merge pull request #6253 from matrix-org/uhoreg/e2e_backup_delete_keys

delete keys when deleting backup versions

changelog.d/6253.bugfix

@@ -0,0 +1 @@
+Delete keys from key backup when deleting backup versions.

synapse/storage/data_stores/main/e2e_room_keys.py

@@ -321,9 +321,17 @@ class EndToEndRoomKeyStore(SQLBaseStore):
         def _delete_e2e_room_keys_version_txn(txn):
             if version is None:
                 this_version = self._get_current_version(txn, user_id)
+                if this_version is None:
+                    raise StoreError(404, "No current backup version")
             else:
                 this_version = version
 
+            self._simple_delete_txn(
+                txn,
+                table="e2e_room_keys",
+                keyvalues={"user_id": user_id, "version": this_version},
+            )
+
             return self._simple_update_one_txn(
                 txn,
                 table="e2e_room_keys_versions",

synapse/storage/data_stores/main/schema/delta/56/delete_keys_from_deleted_backups.sql

@@ -0,0 +1,25 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* delete room keys that belong to deleted room key version, or to room key
+ * versions that don't exist (anymore)
+ */
+DELETE FROM e2e_room_keys
+WHERE version NOT IN (
+  SELECT version
+  FROM e2e_room_keys_versions
+  WHERE e2e_room_keys.user_id = e2e_room_keys_versions.user_id
+  AND e2e_room_keys_versions.deleted = 0
+);

tests/storage/test_e2e_room_keys.py

@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from tests import unittest
+
+# sample room_key data for use in the tests
+room_key = {
+    "first_message_index": 1,
+    "forwarded_count": 1,
+    "is_verified": False,
+    "session_data": "SSBBTSBBIEZJU0gK",
+}
+
+
+class E2eRoomKeysHandlerTestCase(unittest.HomeserverTestCase):
+    def make_homeserver(self, reactor, clock):
+        hs = self.setup_test_homeserver("server", http_client=None)
+        self.store = hs.get_datastore()
+        return hs
+
+    def test_room_keys_version_delete(self):
+        # test that deleting a room key backup deletes the keys
+        version1 = self.get_success(
+            self.store.create_e2e_room_keys_version(
+                "user_id", {"algorithm": "rot13", "auth_data": {}}
+            )
+        )
+
+        self.get_success(
+            self.store.set_e2e_room_key(
+                "user_id", version1, "room", "session", room_key
+            )
+        )
+
+        version2 = self.get_success(
+            self.store.create_e2e_room_keys_version(
+                "user_id", {"algorithm": "rot13", "auth_data": {}}
+            )
+        )
+
+        self.get_success(
+            self.store.set_e2e_room_key(
+                "user_id", version2, "room", "session", room_key
+            )
+        )
+
+        # make sure the keys were stored properly
+        keys = self.get_success(self.store.get_e2e_room_keys("user_id", version1))
+        self.assertEqual(len(keys["rooms"]), 1)
+
+        keys = self.get_success(self.store.get_e2e_room_keys("user_id", version2))
+        self.assertEqual(len(keys["rooms"]), 1)
+
+        # delete version1
+        self.get_success(self.store.delete_e2e_room_keys_version("user_id", version1))
+
+        # make sure the key from version1 is gone, and the key from version2 is
+        # still there
+        keys = self.get_success(self.store.get_e2e_room_keys("user_id", version1))
+        self.assertEqual(len(keys["rooms"]), 0)
+
+        keys = self.get_success(self.store.get_e2e_room_keys("user_id", version2))
+        self.assertEqual(len(keys["rooms"]), 1)