Configure renegotiations on, then disable after the handshake.

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 1024 matching lines @@
   }
 
   if (ssl_config_.signed_cert_timestamps_enabled) {
     SSL_enable_signed_cert_timestamps(ssl_.get());
     SSL_enable_ocsp_stapling(ssl_.get());
   }
 
   if (cert_verifier_->SupportsOCSPStapling())
     SSL_enable_ocsp_stapling(ssl_.get());
 
+  // Configure BoringSSL to allow renegotiations. Once the initial handshake
+  // completes, if renegotiations are not allowed, the default reject value will
+  // be restored. This is done in this order to permit a BoringSSL
+  // optimization. See https://crbug.com/boringssl/123.
+  SSL_set_renegotiate_mode(ssl_.get(), ssl_renegotiate_freely);
+
   return OK;
 }
 
 void SSLClientSocketImpl::DoReadCallback(int rv) {
   // Since Run may result in Read being called, clear |user_read_callback_|
   // up front.
   if (rv > 0)
     was_ever_used_ = true;
   user_read_buf_ = NULL;
   user_read_buf_len_ = 0;
@@ skipping 118 matching lines @@
   size_t ocsp_response_len;
   SSL_get0_ocsp_response(ssl_.get(), &ocsp_response_raw, &ocsp_response_len);
   set_stapled_ocsp_response_received(ocsp_response_len != 0);
   UMA_HISTOGRAM_BOOLEAN("Net.OCSPResponseStapled", ocsp_response_len != 0);
 
   const uint8_t* sct_list;
   size_t sct_list_len;
   SSL_get0_signed_cert_timestamp_list(ssl_.get(), &sct_list, &sct_list_len);
   set_signed_cert_timestamps_received(sct_list_len != 0);
 
-  if (IsRenegotiationAllowed())
-    SSL_set_renegotiate_mode(ssl_.get(), ssl_renegotiate_freely);
+  if (!IsRenegotiationAllowed())
+    SSL_set_renegotiate_mode(ssl_.get(), ssl_renegotiate_never);
 
   uint16_t signature_algorithm = SSL_get_peer_signature_algorithm(ssl_.get());
   if (signature_algorithm != 0) {
     UMA_HISTOGRAM_SPARSE_SLOWLY("Net.SSLSignatureAlgorithm",
                                 signature_algorithm);
   }
 
   // Verify the certificate.
   UpdateServerCert();
   next_handshake_state_ = STATE_VERIFY_CERT;
@@ skipping 845 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