Merge pull request #272 from matrix-org/daniel/insecureclient

Allow configuration to ignore invalid SSL certs

synapse/app/homeserver.py

@@ -221,7 +221,7 @@ class SynapseHomeServer(HomeServer):
                     listener_config,
                     root_resource,
                 ),
-                self.tls_context_factory,
+                self.tls_server_context_factory,
                 interface=bind_address
             )
         else:
@@ -365,7 +365,6 @@ def setup(config_options):
     Args:
         config_options_options: The options passed to Synapse. Usually
             `sys.argv[1:]`.
-        should_run (bool): Whether to start the reactor.
 
     Returns:
         HomeServer
@@ -388,7 +387,7 @@ def setup(config_options):
 
     events.USE_FROZEN_DICTS = config.use_frozen_dicts
 
-    tls_context_factory = context_factory.ServerContextFactory(config)
+    tls_server_context_factory = context_factory.ServerContextFactory(config)
 
     database_engine = create_engine(config.database_config["name"])
     config.database_config["args"]["cp_openfun"] = database_engine.on_new_connection
@@ -396,7 +395,7 @@ def setup(config_options):
     hs = SynapseHomeServer(
         config.server_name,
         db_config=config.database_config,
-        tls_context_factory=tls_context_factory,
+        tls_server_context_factory=tls_server_context_factory,
         config=config,
         content_addr=config.content_addr,
         version_string=version_string,

synapse/config/tls.py

@@ -42,6 +42,14 @@ class TlsConfig(Config):
             config.get("tls_dh_params_path"), "tls_dh_params"
         )
 
+        # This config option applies to non-federation HTTP clients
+        # (e.g. for talking to recaptcha, identity servers, and such)
+        # It should never be used in production, and is intended for
+        # use only when running tests.
+        self.use_insecure_ssl_client_just_for_testing_do_not_use = config.get(
+            "use_insecure_ssl_client_just_for_testing_do_not_use"
+        )
+
     def default_config(self, config_dir_path, server_name):
         base_key_name = os.path.join(config_dir_path, server_name)
 

synapse/crypto/keyring.py

@@ -470,7 +470,7 @@ class Keyring(object):
                 continue
 
             (response, tls_certificate) = yield fetch_server_key(
-                server_name, self.hs.tls_context_factory,
+                server_name, self.hs.tls_server_context_factory,
                 path=(b"/_matrix/key/v2/server/%s" % (
                     urllib.quote(requested_key_id),
                 )).encode("ascii"),
@@ -604,7 +604,7 @@ class Keyring(object):
         # Try to fetch the key from the remote server.
 
         (response, tls_certificate) = yield fetch_server_key(
-            server_name, self.hs.tls_context_factory
+            server_name, self.hs.tls_server_context_factory
         )
 
         # Check the response.

synapse/handlers/auth.py

@@ -19,7 +19,6 @@ from ._base import BaseHandler
 from synapse.api.constants import LoginType
 from synapse.types import UserID
 from synapse.api.errors import LoginError, Codes
-from synapse.http.client import SimpleHttpClient
 from synapse.util.async import run_on_reactor
 
 from twisted.web.client import PartialDownloadError
@@ -187,7 +186,7 @@ class AuthHandler(BaseHandler):
         # TODO: get this from the homeserver rather than creating a new one for
         # each request
         try:
-            client = SimpleHttpClient(self.hs)
+            client = self.hs.get_simple_http_client()
             resp_body = yield client.post_urlencoded_get_json(
                 self.hs.config.recaptcha_siteverify_api,
                 args={

synapse/http/client.py

@@ -12,6 +12,8 @@
 # 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 OpenSSL import SSL
+from OpenSSL.SSL import VERIFY_NONE
 
 from synapse.api.errors import CodeMessageException
 from synapse.util.logcontext import preserve_context_over_fn
@@ -19,7 +21,7 @@ import synapse.metrics
 
 from canonicaljson import encode_canonical_json
 
-from twisted.internet import defer, reactor
+from twisted.internet import defer, reactor, ssl
 from twisted.web.client import (
     Agent, readBody, FileBodyProducer, PartialDownloadError,
     HTTPConnectionPool,
@@ -59,7 +61,12 @@ class SimpleHttpClient(object):
         # 'like a browser'
         pool = HTTPConnectionPool(reactor)
         pool.maxPersistentPerHost = 10
-        self.agent = Agent(reactor, pool=pool)
+        self.agent = Agent(
+            reactor,
+            pool=pool,
+            connectTimeout=15,
+            contextFactory=hs.get_http_client_context_factory()
+        )
         self.version_string = hs.version_string
 
     def request(self, method, uri, *args, **kwargs):
@@ -252,3 +259,18 @@ def _print_ex(e):
             _print_ex(ex)
     else:
         logger.exception(e)
+
+
+class InsecureInterceptableContextFactory(ssl.ContextFactory):
+    """
+    Factory for PyOpenSSL SSL contexts which accepts any certificate for any domain.
+
+    Do not use this since it allows an attacker to intercept your communications.
+    """
+
+    def __init__(self):
+        self._context = SSL.Context(SSL.SSLv23_METHOD)
+        self._context.set_verify(VERIFY_NONE, lambda *_: None)
+
+    def getContext(self, hostname, port):
+        return self._context

synapse/http/matrixfederationclient.py

@@ -57,14 +57,14 @@ incoming_responses_counter = metrics.register_counter(
 
 class MatrixFederationEndpointFactory(object):
     def __init__(self, hs):
-        self.tls_context_factory = hs.tls_context_factory
+        self.tls_server_context_factory = hs.tls_server_context_factory
 
     def endpointForURI(self, uri):
         destination = uri.netloc
 
         return matrix_federation_endpoint(
             reactor, destination, timeout=10,
-            ssl_context_factory=self.tls_context_factory
+            ssl_context_factory=self.tls_server_context_factory
         )
 
 

synapse/server.py

@@ -19,7 +19,9 @@
 # partial one for unit test mocking.
 
 # Imports required for the default HomeServer() implementation
+from twisted.web.client import BrowserLikePolicyForHTTPS
 from synapse.federation import initialize_http_replication
+from synapse.http.client import SimpleHttpClient,  InsecureInterceptableContextFactory
 from synapse.notifier import Notifier
 from synapse.api.auth import Auth
 from synapse.handlers import Handlers
@@ -87,6 +89,8 @@ class BaseHomeServer(object):
         'pusherpool',
         'event_builder_factory',
         'filtering',
+        'http_client_context_factory',
+        'simple_http_client',
     ]
 
     def __init__(self, hostname, **kwargs):
@@ -174,6 +178,17 @@ class HomeServer(BaseHomeServer):
     def build_auth(self):
         return Auth(self)
 
+    def build_http_client_context_factory(self):
+        config = self.get_config()
+        return (
+            InsecureInterceptableContextFactory()
+            if config.use_insecure_ssl_client_just_for_testing_do_not_use
+            else BrowserLikePolicyForHTTPS()
+        )
+
+    def build_simple_http_client(self):
+        return SimpleHttpClient(self)
+
     def build_v1auth(self):
         orf = Auth(self)
         # Matrix spec makes no reference to what HTTP status code is returned,