Issue #19500: Add client-side SSL session resumption to the ssl module.

1 files changed, 110 insertions, 2 deletions

diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py
index aed226c7e1..61744ae95a 100644
--- a/Lib/test/test_ssl.py
+++ b/Lib/test/test_ssl.py
@@ -2163,7 +2163,8 @@ if _have_threads:
             self.server.close()
 
     def server_params_test(client_context, server_context, indata=b"FOO\n",
-                           chatty=True, connectionchatty=False, sni_name=None):
+                           chatty=True, connectionchatty=False, sni_name=None,
+                           session=None):
         """
         Launch a server, connect a client to it and try various reads
         and writes.
@@ -2174,7 +2175,7 @@ if _have_threads:
                                     connectionchatty=False)
         with server:
             with client_context.wrap_socket(socket.socket(),
-                    server_hostname=sni_name) as s:
+                    server_hostname=sni_name, session=session) as s:
                 s.connect((HOST, server.port))
                 for arg in [indata, bytearray(indata), memoryview(indata)]:
                     if connectionchatty:
@@ -2202,6 +2203,8 @@ if _have_threads:
                     'client_alpn_protocol': s.selected_alpn_protocol(),
                     'client_npn_protocol': s.selected_npn_protocol(),
                     'version': s.version(),
+                    'session_reused': s.session_reused,
+                    'session': s.session,
                 })
                 s.close()
             stats['server_alpn_protocols'] = server.selected_alpn_protocols
@@ -3412,6 +3415,111 @@ if _have_threads:
                         s.sendfile(file)
                         self.assertEqual(s.recv(1024), TEST_DATA)
 
+        def test_session(self):
+            server_context = ssl.SSLContext(ssl.PROTOCOL_TLSv1)
+            server_context.load_cert_chain(SIGNED_CERTFILE)
+            client_context = ssl.SSLContext(ssl.PROTOCOL_TLSv1)
+            client_context.verify_mode = ssl.CERT_REQUIRED
+            client_context.load_verify_locations(SIGNING_CA)
+
+            # first conncetion without session
+            stats = server_params_test(client_context, server_context)
+            session = stats['session']
+            self.assertTrue(session.id)
+            self.assertGreater(session.time, 0)
+            self.assertGreater(session.timeout, 0)
+            self.assertTrue(session.has_ticket)
+            if ssl.OPENSSL_VERSION_INFO > (1, 0, 1):
+                self.assertGreater(session.ticket_lifetime_hint, 0)
+            self.assertFalse(stats['session_reused'])
+            sess_stat = server_context.session_stats()
+            self.assertEqual(sess_stat['accept'], 1)
+            self.assertEqual(sess_stat['hits'], 0)
+
+            # reuse session
+            stats = server_params_test(client_context, server_context, session=session)
+            sess_stat = server_context.session_stats()
+            self.assertEqual(sess_stat['accept'], 2)
+            self.assertEqual(sess_stat['hits'], 1)
+            self.assertTrue(stats['session_reused'])
+            session2 = stats['session']
+            self.assertEqual(session2.id, session.id)
+            self.assertEqual(session2, session)
+            self.assertIsNot(session2, session)
+            self.assertGreaterEqual(session2.time, session.time)
+            self.assertGreaterEqual(session2.timeout, session.timeout)
+
+            # another one without session
+            stats = server_params_test(client_context, server_context)
+            self.assertFalse(stats['session_reused'])
+            session3 = stats['session']
+            self.assertNotEqual(session3.id, session.id)
+            self.assertNotEqual(session3, session)
+            sess_stat = server_context.session_stats()
+            self.assertEqual(sess_stat['accept'], 3)
+            self.assertEqual(sess_stat['hits'], 1)
+
+            # reuse session again
+            stats = server_params_test(client_context, server_context, session=session)
+            self.assertTrue(stats['session_reused'])
+            session4 = stats['session']
+            self.assertEqual(session4.id, session.id)
+            self.assertEqual(session4, session)
+            self.assertGreaterEqual(session4.time, session.time)
+            self.assertGreaterEqual(session4.timeout, session.timeout)
+            sess_stat = server_context.session_stats()
+            self.assertEqual(sess_stat['accept'], 4)
+            self.assertEqual(sess_stat['hits'], 2)
+
+        def test_session_handling(self):
+            context = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
+            context.verify_mode = ssl.CERT_REQUIRED
+            context.load_verify_locations(CERTFILE)
+            context.load_cert_chain(CERTFILE)
+
+            context2 = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
+            context2.verify_mode = ssl.CERT_REQUIRED
+            context2.load_verify_locations(CERTFILE)
+            context2.load_cert_chain(CERTFILE)
+
+            server = ThreadedEchoServer(context=context, chatty=False)
+            with server:
+                with context.wrap_socket(socket.socket()) as s:
+                    # session is None before handshake
+                    self.assertEqual(s.session, None)
+                    self.assertEqual(s.session_reused, None)
+                    s.connect((HOST, server.port))
+                    session = s.session
+                    self.assertTrue(session)
+                    with self.assertRaises(TypeError) as e:
+                        s.session = object
+                    self.assertEqual(str(e.exception), 'Value is not a SSLSession.')
+
+                with context.wrap_socket(socket.socket()) as s:
+                    s.connect((HOST, server.port))
+                    # cannot set session after handshake
+                    with self.assertRaises(ValueError) as e:
+                        s.session = session
+                    self.assertEqual(str(e.exception),
+                                     'Cannot set session after handshake.')
+
+                with context.wrap_socket(socket.socket()) as s:
+                    # can set session before handshake and before the
+                    # connection was established
+                    s.session = session
+                    s.connect((HOST, server.port))
+                    self.assertEqual(s.session.id, session.id)
+                    self.assertEqual(s.session, session)
+                    self.assertEqual(s.session_reused, True)
+
+                with context2.wrap_socket(socket.socket()) as s:
+                    # cannot re-use session with a different SSLContext
+                    with self.assertRaises(ValueError) as e:
+                        s.session = session
+                        s.connect((HOST, server.port))
+                    self.assertEqual(str(e.exception),
+                                     'Session refers to a different SSLContext.')
+
 
 def test_main(verbose=False):
     if support.verbose: