This CL adds methods to manipulate RTP header extension, particularly

content/browser/renderer_host/p2p/socket_host_tcp.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 "content/browser/renderer_host/p2p/socket_host_tcp.h"
 
 #include "base/sys_byteorder.h"
 #include "content/common/p2p_messages.h"
 #include "ipc/ipc_sender.h"
 #include "jingle/glue/fake_ssl_client_socket.h"
 #include "jingle/glue/proxy_resolving_client_socket.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_util.h"
 #include "net/socket/client_socket_factory.h"
 #include "net/socket/client_socket_handle.h"
 #include "net/socket/ssl_client_socket.h"
 #include "net/socket/tcp_client_socket.h"
 #include "net/url_request/url_request_context.h"
 #include "net/url_request/url_request_context_getter.h"
+#include "third_party/libjingle/source/talk/base/asyncpacketsocket.h"
 
 namespace {
 
 typedef uint16 PacketLength;
 const int kPacketHeaderSize = sizeof(PacketLength);
 const int kReadBufferSize = 4096;
 const int kPacketLengthOffset = 2;
 const int kTurnChannelDataHeaderSize = 4;
 const int kRecvSocketBufferSize = 128 * 1024;
 const int kSendSocketBufferSize = 128 * 1024;
@@ skipping 277 matching lines @@
     P2PSocketHost::StunMessageType type = P2PSocketHost::StunMessageType();
     bool stun = GetStunPacketType(&*data.begin(), data.size(), &type);
     if (!stun || type == STUN_DATA_INDICATION) {
       LOG(ERROR) << "Page tried to send a data packet to " << to.ToString()
                  << " before STUN binding is finished.";
       OnError();
       return;
     }
   }
 
-  DoSend(to, data);
+  DoSend(to, data, options);
 }
 
 void P2PSocketHostTcpBase::WriteOrQueue(
     scoped_refptr<net::DrainableIOBuffer>& buffer) {
   if (write_buffer_.get()) {
     write_queue_.push(buffer);
     return;
   }
 
   write_buffer_ = buffer;
@@ skipping 111 matching lines @@
 
   int consumed = kPacketHeaderSize;
   char* cur = input + consumed;
   std::vector<char> data(cur, cur + packet_size);
   OnPacket(data);
   consumed += packet_size;
   return consumed;
 }
 
 void P2PSocketHostTcp::DoSend(const net::IPEndPoint& to,
-                              const std::vector<char>& data) {
+                              const std::vector<char>& data,
+                              const talk_base::PacketOptions& options) {
   int size = kPacketHeaderSize + data.size();
   scoped_refptr<net::DrainableIOBuffer> buffer =
       new net::DrainableIOBuffer(new net::IOBuffer(size), size);
   *reinterpret_cast<uint16*>(buffer->data()) = base::HostToNet16(data.size());
   memcpy(buffer->data() + kPacketHeaderSize, &data[0], data.size());
 
+  packet_processing_helpers::MaybeUpdatePacketAbsSendTimeExtnAndRtpAuthTag(
+      buffer->data(), buffer->BytesRemaining(), options);
+
   WriteOrQueue(buffer);
 }
 
 // P2PSocketHostStunTcp
 P2PSocketHostStunTcp::P2PSocketHostStunTcp(
     IPC::Sender* message_sender, int id,
     P2PSocketType type, net::URLRequestContextGetter* url_context)
     : P2PSocketHostTcpBase(message_sender, id, type, url_context) {
   DCHECK(type == P2P_SOCKET_STUN_TCP_CLIENT ||
          type == P2P_SOCKET_STUN_SSLTCP_CLIENT ||
@@ skipping 18 matching lines @@
   int consumed = 0;
   char* cur = input;
   std::vector<char> data(cur, cur + packet_size);
   OnPacket(data);
   consumed += packet_size;
   consumed += pad_bytes;
   return consumed;
 }
 
 void P2PSocketHostStunTcp::DoSend(const net::IPEndPoint& to,
-                                  const std::vector<char>& data) {
+                                  const std::vector<char>& data,
+                                  const talk_base::PacketOptions& options) {
   // Each packet is expected to have header (STUN/TURN ChannelData), where
   // header contains message type and and length of message.
   if (data.size() < kPacketHeaderSize + kPacketLengthOffset) {
     NOTREACHED();
     OnError();
     return;
   }
 
   int pad_bytes;
   size_t expected_len = GetExpectedPacketSize(
       &data[0], data.size(), &pad_bytes);
 
   // Accepts only complete STUN/TURN packets.
   if (data.size() != expected_len) {
     NOTREACHED();
     OnError();
     return;
   }
 
   // Add any pad bytes to the total size.
   int size = data.size() + pad_bytes;
 
   scoped_refptr<net::DrainableIOBuffer> buffer =
       new net::DrainableIOBuffer(new net::IOBuffer(size), size);
   memcpy(buffer->data(), &data[0], data.size());
 
+  // Update HMAC before writing padding bytes at the end.

[Solis, 2014/03/06 09:41:53]

Comment is not true. AST will also be updated if present.

[Mallinath (Gone from Chromium), 2014/03/06 16:18:13]

comment is still true, I just not mentioned AST in it. The reason i mentioned
only HMAC is, we may calculate different HMAC if we write padding bytes.

On 2014/03/06 09:41:53, Solis wrote:

[Solis, 2014/03/06 16:36:28]

Don't you think that is misleading? Remove the comment.

On 2014/03/06 16:18:13, mallinath2 wrote:

[Mallinath (Gone from Chromium), 2014/03/07 04:02:37]

Done.

+  packet_processing_helpers::MaybeUpdatePacketAbsSendTimeExtnAndRtpAuthTag(
+      buffer->data(), data.size(), options);
+
   if (pad_bytes) {
     char padding[4] = {0};
     DCHECK_LE(pad_bytes, 4);
     memcpy(buffer->data() + data.size(), padding, pad_bytes);
   }
   WriteOrQueue(buffer);
 }
 
 int P2PSocketHostStunTcp::GetExpectedPacketSize(
     const char* data, int len, int* pad_bytes) {
@@ skipping 12 matching lines @@
   } else {
     packet_size += kTurnChannelDataHeaderSize;
     // Calculate any padding if present.
     if (packet_size % 4)
       *pad_bytes = 4 - packet_size % 4;
   }
   return packet_size;
 }
 
 }  // namespace content