This CL adds methods to manipulate RTP header extension, particularly

content/browser/renderer_host/p2p/socket_host.h

 // Copyright (c) 2011 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_P2P_SOCKET_HOST_H_
 #define CONTENT_BROWSER_RENDERER_HOST_P2P_SOCKET_HOST_H_
 
 #include "content/common/content_export.h"
 #include "content/common/p2p_socket_type.h"
 #include "net/base/ip_endpoint.h"
 #include "net/udp/datagram_socket.h"
 
 namespace IPC {
 class Sender;
 }
 
 namespace net {
 class URLRequestContextGetter;
 }
 
 namespace talk_base {
 struct PacketOptions;
 }
 
 namespace content {
 class P2PMessageThrottler;
 
+namespace packet_processing_helpers {
+
+// This method can handle only RTP packet, otherwise this method must not be
+// called. It will try to do, 1. update absolute send time extension header
+// if present with current time and 2. update HMAC in RTP packet.
+// If time_in_sec is 0, ApplyPacketOption will call get current time from
+// system.
+bool ApplyPacketOptions(char* data, int length,
+                        const talk_base::PacketOptions& options,
+                        uint64 time_in_sec);

[Solis, 2014/03/07 09:39:42]

I'm sorry, but "time_in_sec" is wrong. This value is poked directly into the ast
field so it is definitely not in seconds. Maybe it's better to call it
abs_send_time and make it a uint32.

[Mallinath (Gone from Chromium), 2014/03/07 22:17:22]

That's very good point. Thanks.
On 2014/03/07 09:39:42, Solis wrote:

+
+// Helper method which finds RTP ofset and length if the packet is encapsulated
+// in a TURN Channel Message or TURN Send Indication message.
+bool GetRtpPacketStartPositionAndLength(char* data, int length,
+                                        int* rtp_start_pos,
+                                        int* rtp_packet_length);
+// Helper method which updates absoulute send time extension if present.
+bool UpdateRtpAbsSendTimeExtn(char* rtp, int length,
+                              int extension_id, uint64 time_in_sec);
+
+}  // packet_processing_helpers
+
 // Base class for P2P sockets.
 class CONTENT_EXPORT P2PSocketHost {
  public:
   static const int kStunHeaderSize = 20;
   // Creates P2PSocketHost of the specific type.
   static P2PSocketHost* Create(IPC::Sender* message_sender,
                                int id, P2PSocketType type,
                                net::URLRequestContextGetter* url_context,
                                P2PMessageThrottler* throttler);
 
   virtual ~P2PSocketHost();
 
   // Initalizes the socket. Returns false when initiazations fails.
   virtual bool Init(const net::IPEndPoint& local_address,
                     const net::IPEndPoint& remote_address) = 0;
 
   // Sends |data| on the socket to |to|.
   virtual void Send(const net::IPEndPoint& to,
                     const std::vector<char>& data,
                     const talk_base::PacketOptions& options,
                     uint64 packet_id) = 0;
 
   virtual P2PSocketHost* AcceptIncomingTcpConnection(
       const net::IPEndPoint& remote_address, int id) = 0;
 
   virtual bool SetOption(P2PSocketOption option, int value) = 0;
 
  protected:
-  friend class P2PSocketHostTcpTestBase;
 
   // TODO(mallinath) - Remove this below enum and use one defined in
   // libjingle/souce/talk/p2p/base/stun.h
   enum StunMessageType {
     STUN_BINDING_REQUEST = 0x0001,
     STUN_BINDING_RESPONSE = 0x0101,
     STUN_BINDING_ERROR_RESPONSE = 0x0111,
     STUN_SHARED_SECRET_REQUEST = 0x0002,
     STUN_SHARED_SECRET_RESPONSE = 0x0102,
     STUN_SHARED_SECRET_ERROR_RESPONSE = 0x0112,
@@ skipping 33 matching lines @@
   IPC::Sender* message_sender_;
   int id_;
   State state_;
 
   DISALLOW_COPY_AND_ASSIGN(P2PSocketHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_P2P_SOCKET_HOST_H_