Do not generate self-signed TLS certificates by default. (#4509)

tests/config/test_generate.py

@@ -50,8 +50,6 @@ class ConfigGenerationTestCase(unittest.TestCase):
                     "homeserver.yaml",
                     "lemurs.win.log.config",
                     "lemurs.win.signing.key",
-                    "lemurs.win.tls.crt",
-                    "lemurs.win.tls.key",
                 ]
             ),
             set(os.listdir(self.dir)),

tests/config/test_tls.py

@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# 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 os
+
+from synapse.config.tls import TlsConfig
+
+from tests.unittest import TestCase
+
+
+class TLSConfigTests(TestCase):
+
+    def test_warn_self_signed(self):
+        """
+        Synapse will give a warning when it loads a self-signed certificate.
+        """
+        config_dir = self.mktemp()
+        os.mkdir(config_dir)
+        with open(os.path.join(config_dir, "cert.pem"), 'w') as f:
+            f.write("""-----BEGIN CERTIFICATE-----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=
+-----END CERTIFICATE-----""")
+
+        config = {
+            "tls_certificate_path": os.path.join(config_dir, "cert.pem"),
+            "no_tls": True,
+            "tls_fingerprints": []
+        }
+
+        t = TlsConfig()
+        t.read_config(config)
+        t.read_certificate_from_disk()
+
+        warnings = self.flushWarnings()
+        self.assertEqual(len(warnings), 1)
+        self.assertEqual(
+            warnings[0]["message"],
+            (
+                "Self-signed TLS certificates will not be accepted by "
+                "Synapse 1.0. Please either provide a valid certificate, "
+                "or use Synapse's ACME support to provision one."
+            )
+        )