//Request Process(Local part)
bool __fastcall LocalRequestProcess(const char *OriginalSend, const size_t SendSize, PSTR OriginalRecv, const uint16_t Protocol, const SOCKET_DATA &LocalSocketData)
{
size_t DataLength = 0;
//TCP Mode
if (Parameter.RequestMode_Transport == REQUEST_MODE_TCP || Protocol == IPPROTO_TCP)
{
DataLength = TCPRequest(OriginalSend, SendSize, OriginalRecv, LARGE_PACKET_MAXSIZE, true);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < LARGE_PACKET_MAXSIZE)
{
SendToRequester(OriginalRecv, DataLength, Protocol, LocalSocketData);
return true;
}
}
//UDP Mode(REQUEST_MODE_UDP)
if (Protocol == IPPROTO_TCP) //TCP requesting
DataLength = LARGE_PACKET_MAXSIZE;
//UDP requesting
else
DataLength = PACKET_MAXSIZE;
DataLength = UDPCompleteRequest(OriginalSend, SendSize, OriginalRecv, DataLength, true);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && (DataLength < PACKET_MAXSIZE || Protocol == IPPROTO_TCP && DataLength < LARGE_PACKET_MAXSIZE))
{
SendToRequester(OriginalRecv, DataLength, Protocol, LocalSocketData);
return true;
}
return false;
}
//Request Process(Direct connections part)
bool __fastcall DirectRequestProcess(
const char *OriginalSend,
const size_t SendSize,
PSTR OriginalRecv,
const uint16_t Protocol,
const bool DirectRequest,
const SOCKET_DATA &LocalSocketData)
{
size_t DataLength = 0;
//Direct Request mode check
DataLength = SelectNetworkProtocol();
if (DirectRequest && (DataLength == AF_INET6 && Parameter.DirectRequest == DIRECT_REQUEST_MODE_IPV4 || //IPv6
DataLength == AF_INET && Parameter.DirectRequest == DIRECT_REQUEST_MODE_IPV6)) //IPv4
return false;
//TCP Mode
if (Parameter.RequestMode_Transport == REQUEST_MODE_TCP || Protocol == IPPROTO_TCP)
{
//Multi requesting.
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U)
DataLength = TCPRequestMulti(OriginalSend, SendSize, OriginalRecv, LARGE_PACKET_MAXSIZE);
//Normal requesting
else
DataLength = TCPRequest(OriginalSend, SendSize, OriginalRecv, LARGE_PACKET_MAXSIZE, false);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < LARGE_PACKET_MAXSIZE)
{
SendToRequester(OriginalRecv, DataLength, Protocol, LocalSocketData);
return true;
}
}
//UDP Mode(REQUEST_MODE_UDP)
if (Protocol == IPPROTO_TCP) //TCP requesting
DataLength = LARGE_PACKET_MAXSIZE;
else //UDP requesting
DataLength = PACKET_MAXSIZE;
//Multi requesting.
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U)
DataLength = UDPCompleteRequestMulti(OriginalSend, SendSize, OriginalRecv, DataLength);
//Normal requesting
else
DataLength = UDPCompleteRequest(OriginalSend, SendSize, OriginalRecv, DataLength, false);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && (DataLength < PACKET_MAXSIZE || Protocol == IPPROTO_TCP && DataLength < LARGE_PACKET_MAXSIZE))
{
SendToRequester(OriginalRecv, DataLength, Protocol, LocalSocketData);
return true;
}
return false;
}
//Request Process(SOCKS part)
bool __fastcall SOCKSRequestProcess(
const DNS_PACKET_DATA &Packet,
char *OriginalRecv,
const size_t RecvSize,
const SOCKET_DATA &LocalSocketData)
{
size_t DataLength = 0;
memset(OriginalRecv, 0, RecvSize);
//EDNS switching(Part 1)
size_t EDNS_SwitchLength = Packet.Length;
uint16_t EDNS_Packet_Flags = ((dns_hdr *)(Packet.Buffer))->Flags;
if (Parameter.EDNS_Label && !Parameter.EDNS_Switch.EDNS_SOCKS)
{
//Reset EDNS flags, resource record counts and packet length.
((dns_hdr *)(Packet.Buffer))->Flags = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Flags) & (~DNS_GET_BIT_AD));
((dns_hdr *)(Packet.Buffer))->Flags = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Flags) & (~DNS_GET_BIT_CD));
if (((dns_hdr *)(Packet.Buffer))->Additional > 0)
((dns_hdr *)(Packet.Buffer))->Additional = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Additional) - 1U);
EDNS_SwitchLength -= Packet.EDNS_Record;
}
//UDP request
if (Parameter.SOCKS_Version == SOCKS_VERSION_5 && Parameter.SOCKS_Protocol_Transport == REQUEST_MODE_UDP)
{
//UDP request process
DataLength = SOCKSUDPRequest(Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < RecvSize)
{
SendToRequester(OriginalRecv, DataLength, RecvSize, Packet.Protocol, LocalSocketData);
return true;
}
}
//TCP request
DataLength = SOCKSTCPRequest(Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < RecvSize)
{
SendToRequester(OriginalRecv, DataLength, RecvSize, Packet.Protocol, LocalSocketData);
return true;
}
//EDNS switching(Part 2)
if (Parameter.EDNS_Label && !Parameter.EDNS_Switch.EDNS_SOCKS)
{
((dns_hdr *)(Packet.Buffer))->Flags = EDNS_Packet_Flags;
((dns_hdr *)(Packet.Buffer))->Additional = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Additional) + 1U);
}
return false;
}
bool __fastcall DNSCurveRequestProcess(
const char *OriginalSend,
const size_t SendSize,
PSTR OriginalRecv,
const uint16_t Protocol,
const SOCKET_DATA &LocalSocketData)
{
size_t DataLength = 0;
//TCP requesting
if (DNSCurveParameter.DNSCurveProtocol_Transport == REQUEST_MODE_TCP || Protocol == IPPROTO_TCP)
{
//Multi requesting.
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U)
DataLength = DNSCurveTCPRequestMulti(OriginalSend, SendSize, OriginalRecv, LARGE_PACKET_MAXSIZE);
//Normal requesting
else
DataLength = DNSCurveTCPRequest(OriginalSend, SendSize, OriginalRecv, LARGE_PACKET_MAXSIZE);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < LARGE_PACKET_MAXSIZE)
{
SendToRequester(OriginalRecv, DataLength, Protocol, LocalSocketData);
return true;
}
}
//UDP Mode(REQUEST_MODE_UDP)
if (Protocol == IPPROTO_TCP) //TCP requesting
DataLength = LARGE_PACKET_MAXSIZE;
else //UDP requesting
DataLength = PACKET_MAXSIZE;
//Multi requesting.
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U)
DataLength = DNSCurveUDPRequestMulti(OriginalSend, SendSize, OriginalRecv, DataLength);
//Normal requesting
else
DataLength = DNSCurveUDPRequest(OriginalSend, SendSize, OriginalRecv, DataLength);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && (DataLength < PACKET_MAXSIZE || Protocol == IPPROTO_TCP && DataLength < LARGE_PACKET_MAXSIZE))
{
SendToRequester(OriginalRecv, DataLength, Protocol, LocalSocketData);
return true;
}
return false;
}
//Request Process(TCP part)
bool __fastcall TCPRequestProcess(
const char *OriginalSend,
const size_t SendSize,
PSTR OriginalRecv,
const uint16_t Protocol,
const SOCKET_DATA &LocalSocketData)
{
size_t DataLength = 0;
//Multi requesting.
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U)
DataLength = TCPRequestMulti(OriginalSend, SendSize, OriginalRecv, LARGE_PACKET_MAXSIZE);
//Normal requesting
else
DataLength = TCPRequest(OriginalSend, SendSize, OriginalRecv, LARGE_PACKET_MAXSIZE, false);
//Send response.
if (DataLength >= sizeof(uint16_t) + DNS_PACKET_MINSIZE && DataLength < LARGE_PACKET_MAXSIZE)
{
SendToRequester(OriginalRecv, DataLength, Protocol, LocalSocketData);
return true;
}
return false;
}
//Request Process(TCP part)
bool __fastcall TCPRequestProcess(
const DNS_PACKET_DATA &Packet,
char *OriginalRecv,
const size_t RecvSize,
const SOCKET_DATA &LocalSocketData)
{
size_t DataLength = 0;
memset(OriginalRecv, 0, RecvSize);
//EDNS switching(Part 1)
size_t EDNS_SwitchLength = Packet.Length;
uint16_t EDNS_Packet_Flags = ((dns_hdr *)(Packet.Buffer))->Flags;
if (Parameter.EDNS_Label && !Parameter.EDNS_Switch.EDNS_TCP)
{
//Reset EDNS flags, resource record counts and packet length.
((dns_hdr *)(Packet.Buffer))->Flags = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Flags) & (~DNS_GET_BIT_AD));
((dns_hdr *)(Packet.Buffer))->Flags = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Flags) & (~DNS_GET_BIT_CD));
if (((dns_hdr *)(Packet.Buffer))->Additional > 0)
((dns_hdr *)(Packet.Buffer))->Additional = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Additional) - 1U);
EDNS_SwitchLength -= Packet.EDNS_Record;
}
//Multi request process
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U)
DataLength = TCPRequestMulti(REQUEST_PROCESS_TCP, Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
//Normal request process
else
DataLength = TCPRequest(REQUEST_PROCESS_TCP, Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < RecvSize)
{
SendToRequester(OriginalRecv, DataLength, RecvSize, Packet.Protocol, LocalSocketData);
return true;
}
//EDNS switching(Part 2)
if (Parameter.EDNS_Label && !Parameter.EDNS_Switch.EDNS_TCP)
{
((dns_hdr *)(Packet.Buffer))->Flags = EDNS_Packet_Flags;
((dns_hdr *)(Packet.Buffer))->Additional = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Additional) + 1U);
}
return false;
}
//Request Process(Direct connections part)
bool __fastcall DirectRequestProcess(
const DNS_PACKET_DATA &Packet,
char *OriginalRecv,
const size_t RecvSize,
const bool DirectRequest,
const SOCKET_DATA &LocalSocketData)
{
size_t DataLength = 0;
memset(OriginalRecv, 0, RecvSize);
//Direct Request mode check
DataLength = SelectNetworkProtocol();
if (DirectRequest && (DataLength == AF_INET6 && Parameter.DirectRequest == DIRECT_REQUEST_MODE_IPV4 || //IPv6
DataLength == AF_INET && Parameter.DirectRequest == DIRECT_REQUEST_MODE_IPV6)) //IPv4
return false;
//EDNS switching(Part 1)
size_t EDNS_SwitchLength = Packet.Length;
uint16_t EDNS_Packet_Flags = ((dns_hdr *)(Packet.Buffer))->Flags;
if (Parameter.EDNS_Label && !Parameter.EDNS_Switch.EDNS_Direct)
{
//Reset EDNS flags, resource record counts and packet length.
((dns_hdr *)(Packet.Buffer))->Flags = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Flags) & (~DNS_GET_BIT_AD));
((dns_hdr *)(Packet.Buffer))->Flags = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Flags) & (~DNS_GET_BIT_CD));
if (((dns_hdr *)(Packet.Buffer))->Additional > 0)
((dns_hdr *)(Packet.Buffer))->Additional = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Additional) - 1U);
EDNS_SwitchLength -= Packet.EDNS_Record;
}
//TCP request
if (Parameter.RequestMode_Transport == REQUEST_MODE_TCP || Packet.Protocol == IPPROTO_TCP)
{
//Multi request process
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U)
DataLength = TCPRequestMulti(REQUEST_PROCESS_DIRECT, Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
//Normal request process
else
DataLength = TCPRequest(REQUEST_PROCESS_DIRECT, Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < RecvSize)
{
SendToRequester(OriginalRecv, DataLength, RecvSize, Packet.Protocol, LocalSocketData);
return true;
}
}
//UDP request
if (Parameter.AlternateMultiRequest || Parameter.MultiRequestTimes > 1U) //Multi request process
DataLength = UDPCompleteRequestMulti(REQUEST_PROCESS_DIRECT, Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
else //Normal request process
DataLength = UDPCompleteRequest(REQUEST_PROCESS_DIRECT, Packet.Buffer, EDNS_SwitchLength, OriginalRecv, RecvSize);
//Send response.
if (DataLength >= DNS_PACKET_MINSIZE && DataLength < RecvSize)
{
SendToRequester(OriginalRecv, DataLength, RecvSize, Packet.Protocol, LocalSocketData);
return true;
}
//EDNS switching(Part 2)
if (Parameter.EDNS_Label && !Parameter.EDNS_Switch.EDNS_Direct)
{
((dns_hdr *)(Packet.Buffer))->Flags = EDNS_Packet_Flags;
((dns_hdr *)(Packet.Buffer))->Additional = htons(ntohs(((dns_hdr *)(Packet.Buffer))->Additional) + 1U);
}
return false;
}
//Match port of responses and send responses to system sockets process
bool __fastcall MatchPortToSend(const char *Buffer, const size_t Length, const uint16_t Protocol, const uint16_t Port)
{
//Initialization
std::shared_ptr<SOCKET_DATA> SocketData_Input(new SOCKET_DATA());
memset(SocketData_Input.get(), 0, sizeof(SOCKET_DATA));
uint16_t SystemProtocol = 0;
size_t ReceiveIndex = 0;
//Match port.
std::unique_lock<std::mutex> OutputPacketListMutex(OutputPacketListLock);
for (auto &PortTableIter:OutputPacketList)
{
for (auto &SocketDataIter:PortTableIter.SocketData_Output)
{
if (PortTableIter.ClearPortTime > 0 && //Do not scan timeout data.
Protocol == AF_INET6 && SocketDataIter.AddrLen == sizeof(sockaddr_in6) && SocketDataIter.SockAddr.ss_family == AF_INET6 &&
Port == ((PSOCKADDR_IN6)&SocketDataIter.SockAddr)->sin6_port || //IPv6
Protocol == AF_INET && SocketDataIter.AddrLen == sizeof(sockaddr_in) && SocketDataIter.SockAddr.ss_family == AF_INET &&
Port == ((PSOCKADDR_IN)&SocketDataIter.SockAddr)->sin_port) //IPv4
{
if (Parameter.ReceiveWaiting > 0)
{
++PortTableIter.ReceiveIndex;
ReceiveIndex = PortTableIter.ReceiveIndex;
OutputPacketListLock.unlock();
goto StopLoop;
}
else {
*SocketData_Input = PortTableIter.SocketData_Input;
SystemProtocol = PortTableIter.Protocol_Network;
PortTableIter.ClearPortTime = 0;
goto ClearOutputPacketListData;
}
}
}
}
goto ClearOutputPacketListData;
//Stop loop, wait receiving and match port again.
StopLoop:
Sleep(Parameter.ReceiveWaiting);
OutputPacketListLock.lock();
for (auto &PortTableIter:OutputPacketList)
{
for (auto &SocketDataIter:PortTableIter.SocketData_Output)
{
if (PortTableIter.ClearPortTime > 0 && //Do not scan timeout data.
Protocol == AF_INET6 && SocketDataIter.AddrLen == sizeof(sockaddr_in6) && SocketDataIter.SockAddr.ss_family == AF_INET6 &&
Port == ((PSOCKADDR_IN6)&SocketDataIter.SockAddr)->sin6_port || //IPv6
Protocol == AF_INET && SocketDataIter.AddrLen == sizeof(sockaddr_in) && SocketDataIter.SockAddr.ss_family == AF_INET &&
Port == ((PSOCKADDR_IN)&SocketDataIter.SockAddr)->sin_port) //IPv4
{
if (PortTableIter.ReceiveIndex == ReceiveIndex)
{
*SocketData_Input = PortTableIter.SocketData_Input;
SystemProtocol = PortTableIter.Protocol_Network;
PortTableIter.ClearPortTime = 0;
}
else {
return false;
}
goto ClearOutputPacketListData;
}
}
}
//Stop loop and clear timeout data.
ClearOutputPacketListData:
//Minimum supported system of GetTickCount64() is Windows Vista(Windows XP with SP3 support).
#if (defined(PLATFORM_WIN32) && !defined(PLATFORM_WIN64))
if (Parameter.FunctionPTR_GetTickCount64 != nullptr)
{
while (!OutputPacketList.empty() && OutputPacketList.front().ClearPortTime <= (size_t)((*Parameter.FunctionPTR_GetTickCount64)()))
{
//Mark timeout.
if (OutputPacketList.front().ClearPortTime > 0)
{
if (OutputPacketList.front().Protocol_Network == AF_INET6) //IPv6
{
if (OutputPacketList.front().Protocol_Transport == IPPROTO_TCP) //TCP
++AlternateSwapList.TimeoutTimes[0];
else //UDP
++AlternateSwapList.TimeoutTimes[2U];
}
else if (OutputPacketList.front().Protocol_Network == AF_INET) //IPv4
{
if (OutputPacketList.front().Protocol_Transport == IPPROTO_TCP) //TCP
++AlternateSwapList.TimeoutTimes[1U];
else //UDP
++AlternateSwapList.TimeoutTimes[3U];
}
}
OutputPacketList.pop_front();
}
}
else {
while (!OutputPacketList.empty() && OutputPacketList.front().ClearPortTime <= GetTickCount())
{
//Mark timeout.
if (OutputPacketList.front().ClearPortTime > 0)
{
if (OutputPacketList.front().Protocol_Network == AF_INET6) //IPv6
{
if (OutputPacketList.front().Protocol_Transport == IPPROTO_TCP) //TCP
++AlternateSwapList.TimeoutTimes[0];
else //UDP
++AlternateSwapList.TimeoutTimes[2U];
}
else if (OutputPacketList.front().Protocol_Network == AF_INET) //IPv4
{
if (OutputPacketList.front().Protocol_Transport == IPPROTO_TCP) //TCP
++AlternateSwapList.TimeoutTimes[1U];
else //UDP
++AlternateSwapList.TimeoutTimes[3U];
}
}
OutputPacketList.pop_front();
}
}
#else
while (!OutputPacketList.empty() && OutputPacketList.front().ClearPortTime <= GetTickCount64())
{
//Mark timeout.
if (OutputPacketList.front().ClearPortTime > 0)
{
if (OutputPacketList.front().Protocol_Network == AF_INET6) //IPv6
{
if (OutputPacketList.front().Protocol_Transport == IPPROTO_TCP) //TCP
++AlternateSwapList.TimeoutTimes[0];
else //UDP
++AlternateSwapList.TimeoutTimes[2U];
}
else if (OutputPacketList.front().Protocol_Network == AF_INET) //IPv4
{
if (OutputPacketList.front().Protocol_Transport == IPPROTO_TCP) //TCP
++AlternateSwapList.TimeoutTimes[1U];
else //UDP
++AlternateSwapList.TimeoutTimes[3U];
}
}
OutputPacketList.pop_front();
}
#endif
OutputPacketListMutex.unlock();
//Drop resopnses which not in OutputPacketList.
if (SocketData_Input->Socket == 0 || SocketData_Input->AddrLen == 0 || SocketData_Input->SockAddr.ss_family == 0 || SystemProtocol == 0)
return false;
//Mark DNS Cache.
if (Parameter.CacheType > 0)
MarkDomainCache(Buffer, Length);
//Send to localhost.
SendToRequester((PSTR)Buffer, Length, SystemProtocol, *SocketData_Input);
if (SystemProtocol == IPPROTO_TCP)
return true;
//Check global sockets.
if (Parameter.LocalSocket != nullptr && !Parameter.LocalSocket->empty())
{
for (auto SocketIter:*Parameter.LocalSocket)
{
if (SocketIter == SocketData_Input->Socket)
return true;
}
}
shutdown(SocketData_Input->Socket, SD_BOTH);
closesocket(SocketData_Input->Socket);
return true;
}