//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(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;
}