Security restrictions for P2P UDP Sockets.

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/p2p_sockets.h"
 
+#include "ipc/ipc_message.h"
 #include "net/base/ip_endpoint.h"
 
-class P2PSocketsHost;
-
 // Base class for P2P sockets used by P2PSocketsHost.
 class P2PSocketHost {
  public:
   // Creates P2PSocketHost of the specific type.
-  static P2PSocketHost* Create(P2PSocketsHost* host, int routing_id, int id,
-                               P2PSocketType type);
+  static P2PSocketHost* Create(IPC::Message::Sender* message_sender,
+                               int routing_id, int id, P2PSocketType type);
 
   virtual ~P2PSocketHost();
 
   // Initalizes the socket. Returns false when initiazations fails.
   virtual bool Init(const net::IPEndPoint& local_address) = 0;
 
-  // Sends |data| on the socket to |socket_address|.
-  virtual void Send(const net::IPEndPoint& socket_address,
+  // Sends |data| on the socket to |to|.
+  virtual void Send(const net::IPEndPoint& to,
                     const std::vector<char>& data) = 0;
 
  protected:
-  P2PSocketHost(P2PSocketsHost* host, int routing_id, int id);
+  enum StunPacketType {
+    STUN_INVALID_PACKET,
+    STUN_BINDING_REQUEST,
+    STUN_BINDING_RESPONSE,
+    STUN_BINDING_ERROR,
+    STUN_UNKNOWN_TYPE,
+  };
 
-  P2PSocketsHost* host_;
+  P2PSocketHost(IPC::Message::Sender* message_sender, int routing_id, int id);
+
+  // Verifies that the packet |data| has a valid STUN header.
+  StunPacketType GetStunPacketType(const char* data, int data_size);
+
+  IPC::Message::Sender* message_sender_;
   int routing_id_;
   int id_;
 
   DISALLOW_COPY_AND_ASSIGN(P2PSocketHost);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_P2P_SOCKET_HOST_H_