Add support for GCM cipher suites from RFC 7714.

webrtc/p2p/base/transportchannel.h

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 106 matching lines @@
   virtual bool SetSrtpCiphers(const std::vector<std::string>& ciphers);
 
   // Finds out which DTLS-SRTP cipher was negotiated.
   // TODO(guoweis): Remove this once all dependencies implement this.
   virtual bool GetSrtpCryptoSuite(int* cipher) { return false; }
 
   // Finds out which DTLS cipher was negotiated.
   // TODO(guoweis): Remove this once all dependencies implement this.
   virtual bool GetSslCipherSuite(int* cipher) { return false; }
 
+  // May GCM ciphers be used?
+  virtual bool IsEnableGcmCiphers() const { return false; }
+
   // Gets the local RTCCertificate used for DTLS.
   virtual rtc::scoped_refptr<rtc::RTCCertificate>
   GetLocalCertificate() const = 0;
 
   // Gets a copy of the remote side's SSL certificate, owned by the caller.
   virtual bool GetRemoteSSLCertificate(rtc::SSLCertificate** cert) const = 0;
 
   // Allows key material to be extracted for external encryption.
   virtual bool ExportKeyingMaterial(const std::string& label,
                                     const uint8_t* context,
@@ skipping 37 matching lines @@
   bool writable_;
   bool receiving_;
   DtlsTransportState dtls_state_ = DTLS_TRANSPORT_NEW;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(TransportChannel);
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_TRANSPORTCHANNEL_H_