Delete TLS version fallback code in net/http.

net/http/http_network_transaction_ssl_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
@@ skipping 104 matching lines @@
   MockHostResolver mock_resolver_;
   HttpServerPropertiesImpl http_server_properties_;
   MockCertVerifier cert_verifier_;
   TransportSecurityState transport_security_state_;
   MultiLogCTVerifier ct_verifier_;
   CTPolicyEnforcer ct_policy_enforcer_;
   HttpNetworkSession::Params session_params_;
   std::vector<std::unique_ptr<HttpRequestInfo>> request_info_vector_;
 };
 
-// Tests that HttpNetworkTransaction attempts to fallback from
-// TLS 1.2 to TLS 1.1.
-TEST_F(HttpNetworkTransactionSSLTest, SSLFallback) {
-  ssl_config_service_ = new TLS12SSLConfigService;
-  session_params_.ssl_config_service = ssl_config_service_.get();
-  // |ssl_data1| is for the first handshake (TLS 1.2), which will fail
-  // for protocol reasons (e.g., simulating a version rollback attack).
-  SSLSocketDataProvider ssl_data1(ASYNC, ERR_SSL_PROTOCOL_ERROR);
-  mock_socket_factory_.AddSSLSocketDataProvider(&ssl_data1);
-  StaticSocketDataProvider data1(NULL, 0, NULL, 0);
-  mock_socket_factory_.AddSocketDataProvider(&data1);
-
-  // |ssl_data2| contains the handshake result for a TLS 1.1
-  // handshake which will be attempted after the TLS 1.2
-  // handshake fails.
-  SSLSocketDataProvider ssl_data2(ASYNC, ERR_SSL_PROTOCOL_ERROR);
-  mock_socket_factory_.AddSSLSocketDataProvider(&ssl_data2);
-  StaticSocketDataProvider data2(NULL, 0, NULL, 0);
-  mock_socket_factory_.AddSocketDataProvider(&data2);
-
-  HttpNetworkSession session(session_params_);
-  HttpNetworkTransaction trans(DEFAULT_PRIORITY, &session);
-
-  TestCompletionCallback callback;
-  // This will consume |ssl_data1| and |ssl_data2|.
-  int rv =
-      callback.GetResult(trans.Start(GetRequestInfo("https://www.paypal.com/"),
-                                     callback.callback(), BoundNetLog()));
-  EXPECT_EQ(ERR_SSL_PROTOCOL_ERROR, rv);
-
-  SocketDataProviderArray<SocketDataProvider>& mock_data =
-      mock_socket_factory_.mock_data();
-  // Confirms that |ssl_data1| and |ssl_data2| are consumed.
-  EXPECT_EQ(2u, mock_data.next_index());
-
-  SSLConfig& ssl_config = GetServerSSLConfig(&trans);
-  // |version_max| falls back to TLS 1.1.
-  EXPECT_EQ(SSL_PROTOCOL_VERSION_TLS1_1, ssl_config.version_max);
-  EXPECT_TRUE(ssl_config.version_fallback);
-}
-
 #if !defined(OS_IOS)
 TEST_F(HttpNetworkTransactionSSLTest, TokenBinding) {
   ssl_config_service_ = new TokenBindingSSLConfigService;
   session_params_.ssl_config_service = ssl_config_service_.get();
   ChannelIDService channel_id_service(new DefaultChannelIDStore(NULL),
                                       base::ThreadTaskRunnerHandle::Get());
   session_params_.channel_id_service = &channel_id_service;
 
   SSLSocketDataProvider ssl_data(ASYNC, OK);
   ssl_data.token_binding_negotiated = true;
@@ skipping 67 matching lines @@
 
   HttpRequestHeaders headers;
   ASSERT_TRUE(trans.GetFullRequestHeaders(&headers));
   std::string token_binding_header;
   EXPECT_FALSE(headers.GetHeader(HttpRequestHeaders::kTokenBinding,
                                  &token_binding_header));
 }
 #endif  // !defined(OS_IOS)
 
 }  // namespace net