Issue #22641: In asyncio, the default SSL context for client connections is now created using ssl.create_default_context(), for stronger security.

2 files changed, 19 insertions, 7 deletions

diff --git a/Lib/asyncio/selector_events.py b/Lib/asyncio/selector_events.py
index a55eff78767..c5debf8f02b 100644
--- a/Lib/asyncio/selector_events.py
+++ b/Lib/asyncio/selector_events.py
@@ -689,16 +689,17 @@ class _SelectorSslTransport(_SelectorTransport):
             if not sslcontext:
                 # Client side may pass ssl=True to use a default
                 # context; in that case the sslcontext passed is None.
-                # The default is the same as used by urllib with
-                # cadefault=True.
-                if hasattr(ssl, '_create_stdlib_context'):
-                    sslcontext = ssl._create_stdlib_context(
-                        cert_reqs=ssl.CERT_REQUIRED,
-                        check_hostname=bool(server_hostname))
+                # The default is secure for client connections.
+                if hasattr(ssl, 'create_default_context'):
+                    # Python 3.4+: use up-to-date strong settings.
+                    sslcontext = ssl.create_default_context()
+                    if not server_hostname:
+                        sslcontext.check_hostname = False
                 else:
                     # Fallback for Python 3.3.
                     sslcontext = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
                     sslcontext.options |= ssl.OP_NO_SSLv2
+                    sslcontext.options |= ssl.OP_NO_SSLv3
                     sslcontext.set_default_verify_paths()
                     sslcontext.verify_mode = ssl.CERT_REQUIRED
 
diff --git a/Lib/asyncio/test_utils.py b/Lib/asyncio/test_utils.py
index ac7680de453..3e5eee54397 100644
--- a/Lib/asyncio/test_utils.py
+++ b/Lib/asyncio/test_utils.py
@@ -91,6 +91,13 @@ class SilentWSGIRequestHandler(WSGIRequestHandler):
 
 class SilentWSGIServer(WSGIServer):
 
+    request_timeout = 2
+
+    def get_request(self):
+        request, client_addr = super().get_request()
+        request.settimeout(self.request_timeout)
+        return request, client_addr
+
     def handle_error(self, request, client_address):
         pass
 
@@ -138,7 +145,8 @@ def _run_test_server(*, address, use_ssl=False, server_cls, server_ssl_cls):
     httpd = server_class(address, SilentWSGIRequestHandler)
     httpd.set_app(app)
     httpd.address = httpd.server_address
-    server_thread = threading.Thread(target=httpd.serve_forever)
+    server_thread = threading.Thread(
+        target=lambda: httpd.serve_forever(poll_interval=0.05))
     server_thread.start()
     try:
         yield httpd
@@ -160,12 +168,15 @@ if hasattr(socket, 'AF_UNIX'):
 
     class UnixWSGIServer(UnixHTTPServer, WSGIServer):
 
+        request_timeout = 2
+
         def server_bind(self):
             UnixHTTPServer.server_bind(self)
             self.setup_environ()
 
         def get_request(self):
             request, client_addr = super().get_request()
+            request.settimeout(self.request_timeout)
             # Code in the stdlib expects that get_request
             # will return a socket and a tuple (host, port).
             # However, this isn't true for UNIX sockets,