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 #ifdef POSIX 29 #include <errno.h> 30 #endif // POSIX 31 32 #include "talk/p2p/base/stunserver.h" 33 #include "talk/base/bytebuffer.h" 34 #include "talk/base/logging.h" 35 36 namespace cricket { 37 38 StunServer::StunServer(talk_base::AsyncUDPSocket* socket) : socket_(socket) { 39 socket_->SignalReadPacket.connect(this, &StunServer::OnPacket); 40 } 41 42 StunServer::~StunServer() { 43 socket_->SignalReadPacket.disconnect(this); 44 } 45 46 void StunServer::OnPacket( 47 talk_base::AsyncPacketSocket* socket, const char* buf, size_t size, 48 const talk_base::SocketAddress& remote_addr) { 49 50 // TODO: If appropriate, look for the magic cookie before parsing. 51 52 // Parse the STUN message. 53 talk_base::ByteBuffer bbuf(buf, size); 54 StunMessage msg; 55 if (!msg.Read(&bbuf)) { 56 SendErrorResponse(msg, remote_addr, 400, "Bad Request"); 57 return; 58 } 59 60 // TODO: If this is UDP, then we shouldn't allow non-fully-parsed messages. 61 62 // TODO: If unknown non-optiional (<= 0x7fff) attributes are found, send a 63 // 420 "Unknown Attribute" response. 64 65 // TODO: Check that a message-integrity attribute was given (or send 401 66 // "Unauthorized"). Check that a username attribute was given (or send 67 // 432 "Missing Username"). Look up the username and password. If it 68 // is missing or the HMAC is wrong, send 431 "Integrity Check Failure". 69 70 // Send the message to the appropriate handler function. 71 switch (msg.type()) { 72 case STUN_BINDING_REQUEST: 73 OnBindingRequest(&msg, remote_addr); 74 return; 75 76 case STUN_ALLOCATE_REQUEST: 77 OnAllocateRequest(&msg, remote_addr); 78 return; 79 80 default: 81 SendErrorResponse(msg, remote_addr, 600, "Operation Not Supported"); 82 } 83 } 84 85 void StunServer::OnBindingRequest( 86 StunMessage* msg, const talk_base::SocketAddress& remote_addr) { 87 StunMessage response; 88 response.SetType(STUN_BINDING_RESPONSE); 89 response.SetTransactionID(msg->transaction_id()); 90 91 // Tell the user the address that we received their request from. 92 StunAddressAttribute* mapped_addr = 93 StunAttribute::CreateAddress(STUN_ATTR_MAPPED_ADDRESS); 94 mapped_addr->SetFamily(1); 95 mapped_addr->SetPort(remote_addr.port()); 96 mapped_addr->SetIP(remote_addr.ip()); 97 response.AddAttribute(mapped_addr); 98 99 // Tell the user the address that we are sending the response from. 100 // This method should not be called if socket address is not 101 // allocated yet. 102 bool allocated; 103 talk_base::SocketAddress local_addr = socket_->GetLocalAddress(&allocated); 104 ASSERT(allocated); 105 106 StunAddressAttribute* source_addr = 107 StunAttribute::CreateAddress(STUN_ATTR_SOURCE_ADDRESS); 108 source_addr->SetFamily(1); 109 source_addr->SetPort(local_addr.port()); 110 source_addr->SetIP(local_addr.ip()); 111 response.AddAttribute(source_addr); 112 113 // TODO: Add username and message-integrity. 114 115 // TODO: Add changed-address. (Keep information about three other servers.) 116 117 SendResponse(response, remote_addr); 118 } 119 120 void StunServer::OnAllocateRequest( 121 StunMessage* msg, const talk_base::SocketAddress& addr) { 122 SendErrorResponse(*msg, addr, 600, "Operation Not Supported"); 123 } 124 125 void StunServer::OnSharedSecretRequest( 126 StunMessage* msg, const talk_base::SocketAddress& addr) { 127 SendErrorResponse(*msg, addr, 600, "Operation Not Supported"); 128 } 129 130 void StunServer::OnSendRequest(StunMessage* msg, 131 const talk_base::SocketAddress& addr) { 132 SendErrorResponse(*msg, addr, 600, "Operation Not Supported"); 133 } 134 135 void StunServer::SendErrorResponse( 136 const StunMessage& msg, const talk_base::SocketAddress& addr, 137 int error_code, const char* error_desc) { 138 139 StunMessage err_msg; 140 err_msg.SetType(GetStunErrorResponseType(msg.type())); 141 err_msg.SetTransactionID(msg.transaction_id()); 142 143 StunErrorCodeAttribute* err_code = StunAttribute::CreateErrorCode(); 144 err_code->SetErrorClass(error_code / 100); 145 err_code->SetNumber(error_code % 100); 146 err_code->SetReason(error_desc); 147 err_msg.AddAttribute(err_code); 148 149 SendResponse(err_msg, addr); 150 } 151 152 void StunServer::SendResponse( 153 const StunMessage& msg, const talk_base::SocketAddress& addr) { 154 155 talk_base::ByteBuffer buf; 156 msg.Write(&buf); 157 158 // TODO: Allow response addr attribute if sent from another stun server. 159 160 if (socket_->SendTo(buf.Data(), buf.Length(), addr) < 0) 161 LOG_ERR(LS_ERROR) << "sendto"; 162 } 163 164 } // namespace cricket 165
