| /* |
| * Copyright 2004 The WebRTC Project Authors. All rights reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "p2p/base/stun_server.h" |
| |
| #include <utility> |
| |
| #include "rtc_base/byte_buffer.h" |
| #include "rtc_base/logging.h" |
| |
| namespace cricket { |
| |
| StunServer::StunServer(rtc::AsyncUDPSocket* socket) : socket_(socket) { |
| socket_->SignalReadPacket.connect(this, &StunServer::OnPacket); |
| } |
| |
| StunServer::~StunServer() { |
| socket_->SignalReadPacket.disconnect(this); |
| } |
| |
| void StunServer::OnPacket(rtc::AsyncPacketSocket* socket, |
| const char* buf, |
| size_t size, |
| const rtc::SocketAddress& remote_addr, |
| const int64_t& /* packet_time_us */) { |
| // Parse the STUN message; eat any messages that fail to parse. |
| rtc::ByteBufferReader bbuf(buf, size); |
| StunMessage msg; |
| if (!msg.Read(&bbuf)) { |
| return; |
| } |
| |
| // TODO(?): If unknown non-optional (<= 0x7fff) attributes are found, send a |
| // 420 "Unknown Attribute" response. |
| |
| // Send the message to the appropriate handler function. |
| switch (msg.type()) { |
| case STUN_BINDING_REQUEST: |
| OnBindingRequest(&msg, remote_addr); |
| break; |
| |
| default: |
| SendErrorResponse(msg, remote_addr, 600, "Operation Not Supported"); |
| } |
| } |
| |
| void StunServer::OnBindingRequest(StunMessage* msg, |
| const rtc::SocketAddress& remote_addr) { |
| StunMessage response; |
| GetStunBindResponse(msg, remote_addr, &response); |
| SendResponse(response, remote_addr); |
| } |
| |
| void StunServer::SendErrorResponse(const StunMessage& msg, |
| const rtc::SocketAddress& addr, |
| int error_code, |
| const char* error_desc) { |
| StunMessage err_msg; |
| err_msg.SetType(GetStunErrorResponseType(msg.type())); |
| err_msg.SetTransactionID(msg.transaction_id()); |
| |
| auto err_code = StunAttribute::CreateErrorCode(); |
| err_code->SetCode(error_code); |
| err_code->SetReason(error_desc); |
| err_msg.AddAttribute(std::move(err_code)); |
| |
| SendResponse(err_msg, addr); |
| } |
| |
| void StunServer::SendResponse(const StunMessage& msg, |
| const rtc::SocketAddress& addr) { |
| rtc::ByteBufferWriter buf; |
| msg.Write(&buf); |
| rtc::PacketOptions options; |
| if (socket_->SendTo(buf.Data(), buf.Length(), addr, options) < 0) |
| RTC_LOG_ERR(LS_ERROR) << "sendto"; |
| } |
| |
| void StunServer::GetStunBindResponse(StunMessage* request, |
| const rtc::SocketAddress& remote_addr, |
| StunMessage* response) const { |
| response->SetType(STUN_BINDING_RESPONSE); |
| response->SetTransactionID(request->transaction_id()); |
| |
| // Tell the user the address that we received their request from. |
| std::unique_ptr<StunAddressAttribute> mapped_addr; |
| if (request->IsLegacy()) { |
| mapped_addr = StunAttribute::CreateAddress(STUN_ATTR_MAPPED_ADDRESS); |
| } else { |
| mapped_addr = StunAttribute::CreateXorAddress(STUN_ATTR_XOR_MAPPED_ADDRESS); |
| } |
| mapped_addr->SetAddress(remote_addr); |
| response->AddAttribute(std::move(mapped_addr)); |
| } |
| |
| } // namespace cricket |