1 /* 2 * libjingle 3 * Copyright 2004--2005, Google Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #ifndef TALK_BASE_NATTYPE_H__ 29 #define TALK_BASE_NATTYPE_H__ 30 31 namespace talk_base { 32 33 /* Identifies each type of NAT that can be simulated. */ 34 enum NATType { 35 NAT_OPEN_CONE, 36 NAT_ADDR_RESTRICTED, 37 NAT_PORT_RESTRICTED, 38 NAT_SYMMETRIC 39 }; 40 41 // Implements the rules for each specific type of NAT. 42 class NAT { 43 public: 44 virtual ~NAT() { } 45 46 // Determines whether this NAT uses both source and destination address when 47 // checking whether a mapping already exists. 48 virtual bool IsSymmetric() = 0; 49 50 // Determines whether this NAT drops packets received from a different IP 51 // the one last sent to. 52 virtual bool FiltersIP() = 0; 53 54 // Determines whether this NAT drops packets received from a different port 55 // the one last sent to. 56 virtual bool FiltersPort() = 0; 57 58 // Returns an implementation of the given type of NAT. 59 static NAT* Create(NATType type); 60 }; 61 62 } // namespace talk_base 63 64 #endif // TALK_BASE_NATTYPE_H__ 65
