Adding Short Record Header feature.

net/socket/ssl_client_socket_impl.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 "net/socket/ssl_client_socket_impl.h"
 
 #include <errno.h>
 #include <string.h>
 
 #include <algorithm>
@@ skipping 201 matching lines @@
   if (base::StringToInt(base::FieldTrialList::FindFullName(field_trial),
                         &override_buffer_size)) {
     buffer_size = override_buffer_size;
     buffer_size = std::max(buffer_size, 1000);
     buffer_size = std::min(buffer_size, 2 * kDefaultOpenSSLBufferSize);
   }
 #endif  // !defined(OS_NACL)
   return buffer_size;
 }
 
 #if defined(OS_NACL)

[davidben, 2017/01/02 10:48:10]

Ooh, I guess we don't need to worry about build targets not explicitly
initializing base::Feature anymore:
https://chromium.googlesource.com/chromium/src/+/958f0473b8039a057b0e31412c2a...

 bool AreLegacyECDSACiphersEnabled() {
   return false;
 }
 #else
 // TODO(davidben): Remove this after the ECDSA CBC removal sticks.
 // https:/crbug.com/666191.
 const base::Feature kLegacyECDSACiphersFeature{
     "SSLLegacyECDSACiphers", base::FEATURE_DISABLED_BY_DEFAULT};
 
 bool AreLegacyECDSACiphersEnabled() {
   return base::FeatureList::IsEnabled(kLegacyECDSACiphersFeature);
 }
 #endif
 
+const base::Feature kShortRecordHeaderFeature{
+    "SSLShortRecordHeader", base::FEATURE_DISABLED_BY_DEFAULT};

[davidben, 2017/01/02 10:48:10]

Should this go in testing/variations/fieldtrial_testing_config.json or something
like the TLS 1.3 negotiation was? (To that end, I probably should have put
SSLLegacyECDSACiphers in there. Oops.)

+
 }  // namespace
 
 class SSLClientSocketImpl::SSLContext {
  public:
   static SSLContext* GetInstance() {
     return base::Singleton<SSLContext>::get();
   }
   SSL_CTX* ssl_ctx() { return ssl_ctx_.get(); }
   SSLClientSessionCache* session_cache() { return &session_cache_; }
 
@@ skipping 35 matching lines @@
 
     // Disable the internal session cache. Session caching is handled
     // externally (i.e. by SSLClientSessionCache).
     SSL_CTX_set_session_cache_mode(
         ssl_ctx_.get(), SSL_SESS_CACHE_CLIENT | SSL_SESS_CACHE_NO_INTERNAL);
     SSL_CTX_sess_set_new_cb(ssl_ctx_.get(), NewSessionCallback);
     SSL_CTX_set_timeout(ssl_ctx_.get(), 1 * 60 * 60 /* one hour */);
 
     SSL_CTX_set_grease_enabled(ssl_ctx_.get(), 1);
 
+    if (base::FeatureList::IsEnabled(kShortRecordHeaderFeature)) {
+      SSL_CTX_set_short_header_enabled(ssl_ctx_.get(), 1);
+    }
+
     if (!SSL_CTX_add_client_custom_ext(ssl_ctx_.get(), kTbExtNum,
                                        &TokenBindingAddCallback,
                                        &TokenBindingFreeCallback, nullptr,
                                        &TokenBindingParseCallback, nullptr)) {
       NOTREACHED();
     }
   }
 
   static int TokenBindingAddCallback(SSL* ssl,
                                      unsigned int extension_value,
@@ skipping 1756 matching lines @@
     if (ERR_GET_REASON(info->error_code) == SSL_R_TLSV1_ALERT_ACCESS_DENIED &&
         !certificate_requested_) {
       net_error = ERR_SSL_PROTOCOL_ERROR;
     }
   }
 
   return net_error;
 }
 
 }  // namespace net