1 /* 2 * Copyright 2004 The WebRTC Project Authors. All rights reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef WEBRTC_BASE_NATTYPE_H__ 12 #define WEBRTC_BASE_NATTYPE_H__ 13 14 namespace rtc { 15 16 /* Identifies each type of NAT that can be simulated. */ 17 enum NATType { 18 NAT_OPEN_CONE, 19 NAT_ADDR_RESTRICTED, 20 NAT_PORT_RESTRICTED, 21 NAT_SYMMETRIC 22 }; 23 24 // Implements the rules for each specific type of NAT. 25 class NAT { 26 public: ~NAT()27 virtual ~NAT() { } 28 29 // Determines whether this NAT uses both source and destination address when 30 // checking whether a mapping already exists. 31 virtual bool IsSymmetric() = 0; 32 33 // Determines whether this NAT drops packets received from a different IP 34 // the one last sent to. 35 virtual bool FiltersIP() = 0; 36 37 // Determines whether this NAT drops packets received from a different port 38 // the one last sent to. 39 virtual bool FiltersPort() = 0; 40 41 // Returns an implementation of the given type of NAT. 42 static NAT* Create(NATType type); 43 }; 44 45 } // namespace rtc 46 47 #endif // WEBRTC_BASE_NATTYPE_H__ 48