//Send responses to requester
bool __fastcall SendToRequester(
char *RecvBuffer,
const size_t RecvSize,
const size_t MaxLen,
const uint16_t Protocol,
const SOCKET_DATA &LocalSocketData)
{
//Response check
if (RecvSize < DNS_PACKET_MINSIZE || CheckEmptyBuffer(RecvBuffer, RecvSize) ||
((pdns_hdr)RecvBuffer)->ID == 0 || ((pdns_hdr)RecvBuffer)->Flags == 0) //DNS header ID and flags must not be set 0.
return false;
//TCP protocol
if (Protocol == IPPROTO_TCP)
{
if (AddLengthDataToHeader(RecvBuffer, RecvSize, MaxLen) == EXIT_FAILURE)
{
shutdown(LocalSocketData.Socket, SD_BOTH);
closesocket(LocalSocketData.Socket);
return false;
}
else {
send(LocalSocketData.Socket, RecvBuffer, (int)(RecvSize + sizeof(uint16_t)), 0);
shutdown(LocalSocketData.Socket, SD_BOTH);
closesocket(LocalSocketData.Socket);
}
}
//UDP protocol
else {
sendto(LocalSocketData.Socket, RecvBuffer, (int)RecvSize, 0, (PSOCKADDR)&LocalSocketData.SockAddr, LocalSocketData.AddrLen);
}
return true;
}
//Send responses to requester
bool __fastcall SendToRequester(
PSTR RecvBuffer,
const size_t RecvSize,
const uint16_t Protocol,
const SOCKET_DATA &LocalSocketData)
{
//TCP
if (Protocol == IPPROTO_TCP)
{
if (AddLengthDataToHeader(RecvBuffer, RecvSize, LARGE_PACKET_MAXSIZE) == EXIT_FAILURE)
{
shutdown(LocalSocketData.Socket, SD_BOTH);
closesocket(LocalSocketData.Socket);
return false;
}
send(LocalSocketData.Socket, RecvBuffer, (int)(RecvSize + sizeof(uint16_t)), 0);
shutdown(LocalSocketData.Socket, SD_BOTH);
closesocket(LocalSocketData.Socket);
}
//UDP
else {
sendto(LocalSocketData.Socket, RecvBuffer, (int)RecvSize, 0, (PSOCKADDR)&LocalSocketData.SockAddr, LocalSocketData.AddrLen);
}
return true;
}
//Transmission and reception of SOCKS protocol(TCP)
size_t __fastcall SOCKSTCPRequest(
const char *OriginalSend,
const size_t SendSize,
char *OriginalRecv,
const size_t RecvSize)
{
//Initialization
std::shared_ptr<char> SendBuffer(new char[LARGE_PACKET_MAXSIZE]());
memset(SendBuffer.get(), 0, LARGE_PACKET_MAXSIZE);
SOCKET_DATA TCPSocketData = {0};
memset(OriginalRecv, 0, RecvSize);
//Socket initialization
if (Parameter.SOCKS_Address_IPv6.Storage.ss_family > 0 && //IPv6
(Parameter.SOCKS_Protocol_Network == REQUEST_MODE_NETWORK_BOTH && GlobalRunningStatus.GatewayAvailable_IPv6 || //Auto select
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV6 || //IPv6
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV4 && Parameter.SOCKS_Address_IPv4.Storage.ss_family == 0)) //Non-IPv4
{
TCPSocketData.SockAddr.ss_family = AF_INET6;
((PSOCKADDR_IN6)&TCPSocketData.SockAddr)->sin6_addr = Parameter.SOCKS_Address_IPv6.IPv6.sin6_addr;
((PSOCKADDR_IN6)&TCPSocketData.SockAddr)->sin6_port = Parameter.SOCKS_Address_IPv6.IPv6.sin6_port;
TCPSocketData.AddrLen = sizeof(sockaddr_in6);
TCPSocketData.Socket = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
}
else if (Parameter.SOCKS_Address_IPv4.Storage.ss_family > 0 && //IPv4
(Parameter.SOCKS_Protocol_Network == REQUEST_MODE_NETWORK_BOTH && GlobalRunningStatus.GatewayAvailable_IPv4 || //Auto select
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV4 || //IPv4
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV6 && Parameter.SOCKS_Address_IPv6.Storage.ss_family == 0)) //Non-IPv6
{
TCPSocketData.SockAddr.ss_family = AF_INET;
((PSOCKADDR_IN)&TCPSocketData.SockAddr)->sin_addr = Parameter.SOCKS_Address_IPv4.IPv4.sin_addr;
((PSOCKADDR_IN)&TCPSocketData.SockAddr)->sin_port = Parameter.SOCKS_Address_IPv4.IPv4.sin_port;
TCPSocketData.AddrLen = sizeof(sockaddr_in);
TCPSocketData.Socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
}
else {
return EXIT_FAILURE;
}
//Socket check
if (!SocketSetting(TCPSocketData.Socket, SOCKET_SETTING_INVALID_CHECK, false, nullptr))
{
PrintError(LOG_LEVEL_2, LOG_ERROR_NETWORK, L"SOCKS socket initialization error", 0, nullptr, 0);
return EXIT_FAILURE;
}
//Non-blocking mode setting and Hop Limits setting
if (!SocketSetting(TCPSocketData.Socket, SOCKET_SETTING_NON_BLOCKING_MODE, true, nullptr) ||
TCPSocketData.SockAddr.ss_family == AF_INET6 && !SocketSetting(TCPSocketData.Socket, SOCKET_SETTING_HOP_LIMITS_IPV6, true, nullptr) ||
TCPSocketData.SockAddr.ss_family == AF_INET && (!SocketSetting(TCPSocketData.Socket, SOCKET_SETTING_HOP_LIMITS_IPV4, true, nullptr) ||
!SocketSetting(TCPSocketData.Socket, SOCKET_SETTING_DO_NOT_FRAGMENT, true, nullptr)))
{
shutdown(TCPSocketData.Socket, SD_BOTH);
closesocket(TCPSocketData.Socket);
return EXIT_FAILURE;
}
//Selecting structure setting
fd_set ReadFDS = {0}, WriteFDS = {0};
timeval Timeout = {0};
//Selection exchange process
if (Parameter.SOCKS_Version == SOCKS_VERSION_5)
{
if (!SOCKSSelectionExchange(&TCPSocketData, &ReadFDS, &WriteFDS, &Timeout, SendBuffer.get(), OriginalRecv, RecvSize))
{
shutdown(TCPSocketData.Socket, SD_BOTH);
closesocket(TCPSocketData.Socket);
return EXIT_FAILURE;
}
else {
memset(SendBuffer.get(), 0, LARGE_PACKET_MAXSIZE);
}
}
//Client command request process
if (!SOCKSClientCommandRequest(IPPROTO_TCP, TCPSocketData.Socket, &ReadFDS, &WriteFDS, &Timeout, SendBuffer.get(), OriginalRecv, RecvSize, &TCPSocketData))
{
shutdown(TCPSocketData.Socket, SD_BOTH);
closesocket(TCPSocketData.Socket);
return EXIT_FAILURE;
}
else {
memset(SendBuffer.get(), 0, LARGE_PACKET_MAXSIZE);
}
//Add length of request packet(It must be written in header when transpot with TCP protocol).
memcpy_s(SendBuffer.get(), RecvSize, OriginalSend, SendSize);
SSIZE_T RecvLen = AddLengthDataToHeader(SendBuffer.get(), SendSize, RecvSize);
if (RecvLen < (SSIZE_T)DNS_PACKET_MINSIZE)
{
shutdown(TCPSocketData.Socket, SD_BOTH);
closesocket(TCPSocketData.Socket);
return EXIT_FAILURE;
}
//Socket timeout setting
#if defined(PLATFORM_WIN)
Timeout.tv_sec = Parameter.SOCKS_SocketTimeout_Reliable / SECOND_TO_MILLISECOND;
Timeout.tv_usec = Parameter.SOCKS_SocketTimeout_Reliable % SECOND_TO_MILLISECOND * MICROSECOND_TO_MILLISECOND;
#elif (defined(PLATFORM_LINUX) || defined(PLATFORM_MACX))
Timeout.tv_sec = Parameter.SOCKS_SocketTimeout_Reliable.tv_sec;
Timeout.tv_usec = Parameter.SOCKS_SocketTimeout_Reliable.tv_usec;
#endif
//Data exchange
RecvLen = ProxySocketSelecting(TCPSocketData.Socket, &ReadFDS, &WriteFDS, &Timeout, SendBuffer.get(), RecvLen, OriginalRecv, RecvSize, DNS_PACKET_MINSIZE, nullptr);
shutdown(TCPSocketData.Socket, SD_BOTH);
closesocket(TCPSocketData.Socket);
//Server response check
if (RecvLen >= (SSIZE_T)DNS_PACKET_MINSIZE && ntohs(((uint16_t *)OriginalRecv)[0]) >= DNS_PACKET_MINSIZE &&
RecvLen >= ntohs(((uint16_t *)OriginalRecv)[0]))
{
RecvLen = ntohs(((uint16_t *)OriginalRecv)[0]);
memmove_s(OriginalRecv, RecvSize, OriginalRecv + sizeof(uint16_t), RecvLen);
//Responses check
RecvLen = CheckResponseData(
REQUEST_PROCESS_SOCKS,
OriginalRecv,
RecvLen,
RecvSize,
nullptr);
if (RecvLen < (SSIZE_T)DNS_PACKET_MINSIZE)
return EXIT_FAILURE;
//Mark DNS cache.
if (Parameter.CacheType > 0)
MarkDomainCache(OriginalRecv, RecvLen);
return RecvLen;
}
return EXIT_FAILURE;
}
//Transmission and reception of HTTP protocol
size_t __fastcall HTTPRequest(
const char *OriginalSend,
const size_t SendSize,
char *OriginalRecv,
const size_t RecvSize)
{
//Initialization
SOCKET_DATA HTTPSocketData = {0};
memset(OriginalRecv, 0, RecvSize);
//Socket initialization
if (Parameter.HTTP_Address_IPv6.Storage.ss_family > 0 && //IPv6
(Parameter.HTTP_Protocol == REQUEST_MODE_NETWORK_BOTH && GlobalRunningStatus.GatewayAvailable_IPv6 || //Auto select
Parameter.HTTP_Protocol == REQUEST_MODE_IPV6 || //IPv6
Parameter.HTTP_Protocol == REQUEST_MODE_IPV4 && Parameter.HTTP_Address_IPv4.Storage.ss_family == 0)) //Non-IPv4
{
HTTPSocketData.SockAddr.ss_family = AF_INET6;
((PSOCKADDR_IN6)&HTTPSocketData.SockAddr)->sin6_addr = Parameter.HTTP_Address_IPv6.IPv6.sin6_addr;
((PSOCKADDR_IN6)&HTTPSocketData.SockAddr)->sin6_port = Parameter.HTTP_Address_IPv6.IPv6.sin6_port;
HTTPSocketData.AddrLen = sizeof(sockaddr_in6);
HTTPSocketData.Socket = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
}
else if (Parameter.HTTP_Address_IPv4.Storage.ss_family > 0 && //IPv4
(Parameter.HTTP_Protocol == REQUEST_MODE_NETWORK_BOTH && GlobalRunningStatus.GatewayAvailable_IPv4 || //Auto select
Parameter.HTTP_Protocol == REQUEST_MODE_IPV4 || //IPv4
Parameter.HTTP_Protocol == REQUEST_MODE_IPV6 && Parameter.HTTP_Address_IPv6.Storage.ss_family == 0)) //Non-IPv6
{
HTTPSocketData.SockAddr.ss_family = AF_INET;
((PSOCKADDR_IN)&HTTPSocketData.SockAddr)->sin_addr = Parameter.HTTP_Address_IPv4.IPv4.sin_addr;
((PSOCKADDR_IN)&HTTPSocketData.SockAddr)->sin_port = Parameter.HTTP_Address_IPv4.IPv4.sin_port;
HTTPSocketData.AddrLen = sizeof(sockaddr_in);
HTTPSocketData.Socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
}
else {
return EXIT_FAILURE;
}
//Socket check
if (!SocketSetting(HTTPSocketData.Socket, SOCKET_SETTING_INVALID_CHECK, nullptr))
{
PrintError(LOG_ERROR_NETWORK, L"HTTP socket initialization error", 0, nullptr, 0);
return EXIT_FAILURE;
}
//Non-blocking mode setting
if (!SocketSetting(HTTPSocketData.Socket, SOCKET_SETTING_NON_BLOCKING_MODE, nullptr))
{
shutdown(HTTPSocketData.Socket, SD_BOTH);
closesocket(HTTPSocketData.Socket);
PrintError(LOG_ERROR_NETWORK, L"Socket non-blocking mode setting error", 0, nullptr, 0);
return EXIT_FAILURE;
}
//Selecting structure setting
fd_set ReadFDS = {0}, WriteFDS = {0};
timeval Timeout = {0};
//HTTP CONNECT request
if (Parameter.HTTP_TargetDomain == nullptr || Parameter.HTTP_Version == nullptr ||
!HTTP_CONNECTRequest(&HTTPSocketData, &ReadFDS, &WriteFDS, &Timeout, OriginalRecv, RecvSize))
{
shutdown(HTTPSocketData.Socket, SD_BOTH);
closesocket(HTTPSocketData.Socket);
return EXIT_FAILURE;
}
//Add length of request packet(It must be written in header when transpot with TCP protocol).
std::shared_ptr<char> SendBuffer(new char[LARGE_PACKET_MAXSIZE]());
memset(SendBuffer.get(), 0, LARGE_PACKET_MAXSIZE);
memcpy_s(SendBuffer.get(), RecvSize, OriginalSend, SendSize);
SSIZE_T RecvLen = AddLengthDataToHeader(SendBuffer.get(), SendSize, RecvSize);
if (RecvLen < (SSIZE_T)DNS_PACKET_MINSIZE)
{
shutdown(HTTPSocketData.Socket, SD_BOTH);
closesocket(HTTPSocketData.Socket);
return EXIT_FAILURE;
}
//Socket timeout setting
#if defined(PLATFORM_WIN)
Timeout.tv_sec = Parameter.HTTP_SocketTimeout / SECOND_TO_MILLISECOND;
Timeout.tv_usec = Parameter.HTTP_SocketTimeout % SECOND_TO_MILLISECOND * MICROSECOND_TO_MILLISECOND;
#elif (defined(PLATFORM_LINUX) || defined(PLATFORM_MACX))
Timeout.tv_sec = Parameter.HTTP_SocketTimeout.tv_sec;
Timeout.tv_usec = Parameter.HTTP_SocketTimeout.tv_usec;
#endif
//Data exchange
RecvLen = ProxySocketSelecting(HTTPSocketData.Socket, &ReadFDS, &WriteFDS, &Timeout, SendBuffer.get(), RecvLen, OriginalRecv, RecvSize, DNS_PACKET_MINSIZE, nullptr);
shutdown(HTTPSocketData.Socket, SD_BOTH);
closesocket(HTTPSocketData.Socket);
//Server response check
if (RecvLen >= (SSIZE_T)DNS_PACKET_MINSIZE && ntohs(((uint16_t *)OriginalRecv)[0]) >= DNS_PACKET_MINSIZE &&
RecvLen >= ntohs(((uint16_t *)OriginalRecv)[0]))
{
RecvLen = ntohs(((uint16_t *)OriginalRecv)[0]);
memmove_s(OriginalRecv, RecvSize, OriginalRecv + sizeof(uint16_t), RecvLen);
//Responses check
RecvLen = CheckResponseData(
REQUEST_PROCESS_HTTP,
OriginalRecv,
RecvLen,
RecvSize,
nullptr);
if (RecvLen < (SSIZE_T)DNS_PACKET_MINSIZE)
return EXIT_FAILURE;
//Mark DNS cache.
if (Parameter.CacheType > 0)
MarkDomainCache(OriginalRecv, RecvLen);
return RecvLen;
}
return EXIT_FAILURE;
}
//Transmission and reception of SOCKS protocol(TCP)
size_t __fastcall SOCKSTCPRequest(
const char *OriginalSend,
const size_t SendSize,
PSTR OriginalRecv,
const size_t RecvSize)
{
//Initialization
std::shared_ptr<char> SendBuffer(new char[LARGE_PACKET_MAXSIZE]());
std::shared_ptr<SOCKET_DATA> TCPSocketData(new SOCKET_DATA());
memset(SendBuffer.get(), 0, LARGE_PACKET_MAXSIZE);
memset(TCPSocketData.get(), 0, sizeof(SOCKET_DATA));
//Socket initialization
if (Parameter.SOCKS_Address_IPv6.Storage.ss_family > 0 && //IPv6
(Parameter.SOCKS_Protocol_Network == REQUEST_MODE_NETWORK_BOTH && GlobalRunningStatus.GatewayAvailable_IPv6 || //Auto select
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV6 || //IPv6
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV4 && Parameter.SOCKS_Address_IPv4.Storage.ss_family == 0)) //Non-IPv4
{
TCPSocketData->SockAddr.ss_family = AF_INET6;
((PSOCKADDR_IN6)&TCPSocketData->SockAddr)->sin6_addr = Parameter.SOCKS_Address_IPv6.IPv6.sin6_addr;
((PSOCKADDR_IN6)&TCPSocketData->SockAddr)->sin6_port = Parameter.SOCKS_Address_IPv6.IPv6.sin6_port;
TCPSocketData->AddrLen = sizeof(sockaddr_in6);
TCPSocketData->Socket = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
}
else if (Parameter.SOCKS_Address_IPv4.Storage.ss_family > 0 && //IPv4
(Parameter.SOCKS_Protocol_Network == REQUEST_MODE_NETWORK_BOTH && GlobalRunningStatus.GatewayAvailable_IPv4 || //Auto select
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV4 || //IPv4
Parameter.SOCKS_Protocol_Network == REQUEST_MODE_IPV6 && Parameter.SOCKS_Address_IPv6.Storage.ss_family == 0)) //Non-IPv6
{
TCPSocketData->SockAddr.ss_family = AF_INET;
((PSOCKADDR_IN)&TCPSocketData->SockAddr)->sin_addr = Parameter.SOCKS_Address_IPv4.IPv4.sin_addr;
((PSOCKADDR_IN)&TCPSocketData->SockAddr)->sin_port = Parameter.SOCKS_Address_IPv4.IPv4.sin_port;
TCPSocketData->AddrLen = sizeof(sockaddr_in);
TCPSocketData->Socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
}
else {
return EXIT_FAILURE;
}
//Socket check
if (!SocketSetting(TCPSocketData->Socket, SOCKET_SETTING_INVALID_CHECK, nullptr))
{
PrintError(LOG_ERROR_NETWORK, L"SOCKS socket initialization error", 0, nullptr, 0);
return EXIT_FAILURE;
}
//Non-blocking mode setting
if (!SocketSetting(TCPSocketData->Socket, SOCKET_SETTING_NON_BLOCKING_MODE, nullptr))
{
shutdown(TCPSocketData->Socket, SD_BOTH);
closesocket(TCPSocketData->Socket);
PrintError(LOG_ERROR_NETWORK, L"Socket non-blocking mode setting error", 0, nullptr, 0);
return EXIT_FAILURE;
}
//Selecting structure setting
std::shared_ptr<fd_set> ReadFDS(new fd_set()), WriteFDS(new fd_set());
std::shared_ptr<timeval> Timeout(new timeval());
memset(ReadFDS.get(), 0, sizeof(fd_set));
memset(WriteFDS.get(), 0, sizeof(fd_set));
memset(Timeout.get(), 0, sizeof(timeval));
//Selection exchange process
if (Parameter.SOCKS_Version == SOCKS_VERSION_5)
{
if (!SOCKSSelectionExchange(TCPSocketData.get(), ReadFDS.get(), WriteFDS.get(), Timeout.get(), SendBuffer.get(), OriginalRecv, RecvSize))
{
shutdown(TCPSocketData->Socket, SD_BOTH);
closesocket(TCPSocketData->Socket);
return EXIT_FAILURE;
}
else {
memset(SendBuffer.get(), 0, LARGE_PACKET_MAXSIZE);
}
}
//Client command request process
if (!SOCKSClientCommandRequest(IPPROTO_TCP, TCPSocketData->Socket, ReadFDS.get(), WriteFDS.get(), Timeout.get(), SendBuffer.get(), OriginalRecv, RecvSize, TCPSocketData.get()))
{
shutdown(TCPSocketData->Socket, SD_BOTH);
closesocket(TCPSocketData->Socket);
return EXIT_FAILURE;
}
else {
memset(SendBuffer.get(), 0, LARGE_PACKET_MAXSIZE);
}
//Add length of request packet(It must be written in header when transpot with TCP protocol).
memcpy_s(SendBuffer.get(), RecvSize, OriginalSend, SendSize);
SSIZE_T RecvLen = AddLengthDataToHeader(SendBuffer.get(), SendSize, RecvSize);
if (RecvLen < (SSIZE_T)DNS_PACKET_MINSIZE)
{
shutdown(TCPSocketData->Socket, SD_BOTH);
closesocket(TCPSocketData->Socket);
return EXIT_FAILURE;
}
//Data exchange
RecvLen = SOCKSSocketSelecting(TCPSocketData->Socket, ReadFDS.get(), WriteFDS.get(), Timeout.get(), SendBuffer.get(), RecvLen, OriginalRecv, RecvSize, DNS_PACKET_MINSIZE);
shutdown(TCPSocketData->Socket, SD_BOTH);
closesocket(TCPSocketData->Socket);
if (RecvLen >= (SSIZE_T)DNS_PACKET_MINSIZE)
{
memmove_s(OriginalRecv, RecvSize, OriginalRecv + sizeof(uint16_t), RecvLen);
return RecvLen;
}
return EXIT_FAILURE;
}