1 files changed, 60 insertions, 0 deletions
diff --git a/synapse/rest/voip.py b/synapse/rest/voip.py
new file mode 100644
index 0000000000..2e4627606f
--- /dev/null
+++ b/synapse/rest/voip.py
@@ -0,0 +1,60 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014 OpenMarket 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.
+
+from twisted.internet import defer
+
+from base import RestServlet, client_path_pattern
+
+
+import hmac
+import hashlib
+import base64
+
+
+class VoipRestServlet(RestServlet):
+    PATTERN = client_path_pattern("/voip/turnServer$")
+
+    @defer.inlineCallbacks
+    def on_GET(self, request):
+        auth_user = yield self.auth.get_user_by_req(request)
+
+        turnUris = self.hs.config.turn_uris
+        turnSecret = self.hs.config.turn_shared_secret
+        userLifetime = self.hs.config.turn_user_lifetime
+        if not turnUris or not turnSecret or not userLifetime:
+            defer.returnValue( (200, {}) )
+
+        expiry = self.hs.get_clock().time_msec() + userLifetime
+        username = "%d:%s" % (expiry, auth_user.to_string())
+         
+        mac = hmac.new(turnSecret, msg=username, digestmod=hashlib.sha1)
+        # We need to use standard base64 encoding here, *not* syutil's encode_base64
+        # because we need to add the standard padding to get the same result as the
+        # TURN server.
+        password = base64.b64encode(mac.digest())
+
+        defer.returnValue( (200, {
+            'username': username,
+            'password': password,
+            'ttl': userLifetime / 1000,
+            'uris': turnUris,
+        }) )
+
+    def on_OPTIONS(self, request):
+        return (200, {})
+
+
+def register_servlets(hs, http_server):
+    VoipRestServlet(hs).register(http_server)