Validate client_secret parameter (#6767)

tests/util/test_stringutils.py

@@ -0,0 +1,51 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 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 synapse.api.errors import SynapseError
+from synapse.util.stringutils import assert_valid_client_secret
+
+from .. import unittest
+
+
+class StringUtilsTestCase(unittest.TestCase):
+    def test_client_secret_regex(self):
+        """Ensure that client_secret does not contain illegal characters"""
+        good = [
+            "abcde12345",
+            "ABCabc123",
+            "_--something==_",
+            "...--==-18913",
+            "8Dj2odd-e9asd.cd==_--ddas-secret-",
+            # We temporarily allow : characters: https://github.com/matrix-org/synapse/issues/6766
+            # To be removed in a future release
+            "SECRET:1234567890",
+        ]
+
+        bad = [
+            "--+-/secret",
+            "\\dx--dsa288",
+            "",
+            "AAS//",
+            "asdj**",
+            ">X><Z<!!-)))",
+            "a@b.com",
+        ]
+
+        for client_secret in good:
+            assert_valid_client_secret(client_secret)
+
+        for client_secret in bad:
+            with self.assertRaises(SynapseError):
+                assert_valid_client_secret(client_secret)