Add a tool to decrypt a secret

This is mostly a debugging aid.

Change-Id: I843c9a993299c86b66fa5e6c11aed08769d79980

tools/decrypt_secret.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python
+
+# 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.
+
+import argparse
+from zuul.lib import encryption
+import zuul.configloader
+import zuul.model
+
+
+DESCRIPTION = """Decrypt a Zuul secret.
+"""
+
+
+def main():
+    parser = argparse.ArgumentParser(description=DESCRIPTION)
+    parser.add_argument('private_key',
+                        help="The path to the private key")
+    parser.add_argument('file',
+                        help="The YAML file with secrets")
+    args = parser.parse_args()
+
+    (private_secrets_key, public_secrets_key) = \
+        encryption.deserialize_rsa_keypair(open(args.private_key, 'rb').read())
+    parser = zuul.configloader.SecretParser(None)
+    sc = zuul.model.SourceContext('project', 'master', 'path', False)
+
+    data = zuul.configloader.safe_load_yaml(open(args.file).read(), sc)
+    for element in data:
+        if 'secret' not in element:
+            continue
+        s = element['secret']
+        secret = parser.fromYaml(s)
+        print(secret.name)
+        print(secret.decrypt(private_secrets_key).secret_data)
+
+
+if __name__ == '__main__':
+    main()