diff options
Diffstat (limited to 'src/libui_sdl/LAN_Socket.cpp')
-rw-r--r-- | src/libui_sdl/LAN_Socket.cpp | 1145 |
1 files changed, 0 insertions, 1145 deletions
diff --git a/src/libui_sdl/LAN_Socket.cpp b/src/libui_sdl/LAN_Socket.cpp deleted file mode 100644 index c6fbd4b..0000000 --- a/src/libui_sdl/LAN_Socket.cpp +++ /dev/null @@ -1,1145 +0,0 @@ -/* - Copyright 2016-2020 Arisotura - - This file is part of melonDS. - - melonDS is free software: you can redistribute it and/or modify it under - the terms of the GNU General Public License as published by the Free - Software Foundation, either version 3 of the License, or (at your option) - any later version. - - melonDS is distributed in the hope that it will be useful, but WITHOUT ANY - WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS - FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. - - You should have received a copy of the GNU General Public License along - with melonDS. If not, see http://www.gnu.org/licenses/. -*/ - -// indirect LAN interface, powered by BSD sockets. - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include "../Wifi.h" -#include "LAN_Socket.h" -#include "../Config.h" - -#ifdef __WIN32__ - #include <winsock2.h> - #include <ws2tcpip.h> - #define socket_t SOCKET - #define sockaddr_t SOCKADDR -#else - #include <unistd.h> - #include <arpa/inet.h> - #include <netinet/in.h> - #include <sys/types.h> - #include <sys/select.h> - #include <sys/socket.h> - #include <netdb.h> - #define socket_t int - #define sockaddr_t struct sockaddr - #define closesocket close -#endif - -#ifndef INVALID_SOCKET -#define INVALID_SOCKET (socket_t)-1 -#endif - - -namespace LAN_Socket -{ - -const u32 kSubnet = 0x0A400000; -const u32 kServerIP = kSubnet | 0x01; -const u32 kDNSIP = kSubnet | 0x02; -const u32 kClientIP = kSubnet | 0x10; - -const u8 kServerMAC[6] = {0x00, 0xAB, 0x33, 0x28, 0x99, 0x44}; -const u8 kDNSMAC[6] = {0x00, 0xAB, 0x33, 0x28, 0x99, 0x55}; - -u8 PacketBuffer[2048]; -int PacketLen; -volatile int RXNum; - -u16 IPv4ID; - - -// TODO: UDP sockets -// * use FIFO list -// * assign new socket when seeing new IP/port - - -typedef struct -{ - u8 DestIP[4]; - u16 SourcePort; - u16 DestPort; - - u32 SeqNum; // sequence number for incoming frames - u32 AckNum; - - // 0: unused - // 1: connected - u8 Status; - - socket_t Backend; - -} TCPSocket; - -typedef struct -{ - u8 DestIP[4]; - u16 SourcePort; - u16 DestPort; - - socket_t Backend; - struct sockaddr_in BackendAddr; - -} UDPSocket; - -TCPSocket TCPSocketList[16]; -UDPSocket UDPSocketList[4]; - -int UDPSocketID = 0; - - -bool Init() -{ - // TODO: how to deal with cases where an adapter is unplugged or changes config?? - //if (PCapLib) return true; - - //Lib = NULL; - PacketLen = 0; - RXNum = 0; - - IPv4ID = 1; - - memset(TCPSocketList, 0, sizeof(TCPSocketList)); - memset(UDPSocketList, 0, sizeof(UDPSocketList)); - - UDPSocketID = 0; - - return true; -} - -void DeInit() -{ - for (int i = 0; i < (sizeof(TCPSocketList)/sizeof(TCPSocket)); i++) - { - TCPSocket* sock = &TCPSocketList[i]; - if (sock->Backend) closesocket(sock->Backend); - } - - for (int i = 0; i < (sizeof(UDPSocketList)/sizeof(UDPSocket)); i++) - { - UDPSocket* sock = &UDPSocketList[i]; - if (sock->Backend) closesocket(sock->Backend); - } -} - - -void FinishUDPFrame(u8* data, int len) -{ - u8* ipheader = &data[0xE]; - u8* udpheader = &data[0x22]; - - // lengths - *(u16*)&ipheader[2] = htons(len - 0xE); - *(u16*)&udpheader[4] = htons(len - (0xE + 0x14)); - - // IP checksum - u32 tmp = 0; - - for (int i = 0; i < 20; i += 2) - tmp += ntohs(*(u16*)&ipheader[i]); - while (tmp >> 16) - tmp = (tmp & 0xFFFF) + (tmp >> 16); - tmp ^= 0xFFFF; - *(u16*)&ipheader[10] = htons(tmp); - - // UDP checksum - // (note: normally not mandatory, but some older sgIP versions require it) - tmp = 0; - tmp += ntohs(*(u16*)&ipheader[12]); - tmp += ntohs(*(u16*)&ipheader[14]); - tmp += ntohs(*(u16*)&ipheader[16]); - tmp += ntohs(*(u16*)&ipheader[18]); - tmp += ntohs(0x1100); - tmp += (len-0x22); - for (u8* i = udpheader; i < &udpheader[len-0x23]; i += 2) - tmp += ntohs(*(u16*)i); - if (len & 1) - tmp += ntohs((u_short)udpheader[len-0x23]); - while (tmp >> 16) - tmp = (tmp & 0xFFFF) + (tmp >> 16); - tmp ^= 0xFFFF; - if (tmp == 0) tmp = 0xFFFF; - *(u16*)&udpheader[6] = htons(tmp); -} - -void FinishTCPFrame(u8* data, int len) -{ - u8* ipheader = &data[0xE]; - u8* tcpheader = &data[0x22]; - - // lengths - *(u16*)&ipheader[2] = htons(len - 0xE); - - // IP checksum - u32 tmp = 0; - - for (int i = 0; i < 20; i += 2) - tmp += ntohs(*(u16*)&ipheader[i]); - while (tmp >> 16) - tmp = (tmp & 0xFFFF) + (tmp >> 16); - tmp ^= 0xFFFF; - *(u16*)&ipheader[10] = htons(tmp); - - u32 tcplen = ntohs(*(u16*)&ipheader[2]) - 0x14; - - // TCP checksum - tmp = 0; - tmp += ntohs(*(u16*)&ipheader[12]); - tmp += ntohs(*(u16*)&ipheader[14]); - tmp += ntohs(*(u16*)&ipheader[16]); - tmp += ntohs(*(u16*)&ipheader[18]); - tmp += ntohs(0x0600); - tmp += tcplen; - for (u8* i = tcpheader; i < &tcpheader[tcplen-1]; i += 2) - tmp += ntohs(*(u16*)i); - if (tcplen & 1) - tmp += ntohs((u_short)tcpheader[tcplen-1]); - while (tmp >> 16) - tmp = (tmp & 0xFFFF) + (tmp >> 16); - tmp ^= 0xFFFF; - *(u16*)&tcpheader[16] = htons(tmp); -} - - -void HandleDHCPFrame(u8* data, int len) -{ - u8 type = 0xFF; - - u32 transid = *(u32*)&data[0x2E]; - - u8* options = &data[0x11A]; - for (;;) - { - if (options >= &data[len]) break; - u8 opt = *options++; - if (opt == 255) break; - - u8 len = *options++; - switch (opt) - { - case 53: // frame type - type = options[0]; - break; - } - - options += len; - } - - if (type == 0xFF) - { - printf("DHCP: bad frame\n"); - return; - } - - printf("DHCP: frame type %d, transid %08X\n", type, transid); - - if (type == 1 || // discover - type == 3) // request - { - u8 resp[512]; - u8* out = &resp[0]; - - // ethernet - memcpy(out, &data[6], 6); out += 6; - memcpy(out, kServerMAC, 6); out += 6; - *(u16*)out = htons(0x0800); out += 2; - - // IP - u8* ipheader = out; - *out++ = 0x45; - *out++ = 0x00; - *(u16*)out = 0; out += 2; // total length - *(u16*)out = htons(IPv4ID); out += 2; IPv4ID++; - *out++ = 0x00; - *out++ = 0x00; - *out++ = 0x80; // TTL - *out++ = 0x11; // protocol (UDP) - *(u16*)out = 0; out += 2; // checksum - *(u32*)out = htonl(kServerIP); out += 4; // source IP - if (type == 1) - { - *(u32*)out = htonl(0xFFFFFFFF); out += 4; // destination IP - } - else if (type == 3) - { - *(u32*)out = htonl(kClientIP); out += 4; // destination IP - } - - // UDP - u8* udpheader = out; - *(u16*)out = htons(67); out += 2; // source port - *(u16*)out = htons(68); out += 2; // destination port - *(u16*)out = 0; out += 2; // length - *(u16*)out = 0; out += 2; // checksum - - // DHCP - u8* body = out; - *out++ = 0x02; - *out++ = 0x01; - *out++ = 0x06; - *out++ = 0x00; - *(u32*)out = transid; out += 4; - *(u16*)out = 0; out += 2; // seconds elapsed - *(u16*)out = 0; out += 2; - *(u32*)out = htonl(0x00000000); out += 4; // client IP - *(u32*)out = htonl(kClientIP); out += 4; // your IP - *(u32*)out = htonl(kServerIP); out += 4; // server IP - *(u32*)out = htonl(0x00000000); out += 4; // gateway IP - memcpy(out, &data[6], 6); out += 6; - memset(out, 0, 10); out += 10; - memset(out, 0, 192); out += 192; - *(u32*)out = 0x63538263; out += 4; // DHCP magic - - // DHCP options - *out++ = 53; *out++ = 1; - *out++ = (type==1) ? 2 : 5; // DHCP type: offer/ack - *out++ = 1; *out++ = 4; - *(u32*)out = htonl(0xFFFFFF00); out += 4; // subnet mask - *out++ = 3; *out++ = 4; - *(u32*)out = htonl(kServerIP); out += 4; // router - *out++ = 51; *out++ = 4; - *(u32*)out = htonl(442030); out += 4; // lease time - *out++ = 54; *out++ = 4; - *(u32*)out = htonl(kServerIP); out += 4; // DHCP server - *out++ = 6; *out++ = 4; - *(u32*)out = htonl(kDNSIP); out += 4; // DNS (hax) - - *out++ = 0xFF; - memset(out, 0, 20); out += 20; - - u32 framelen = (u32)(out - &resp[0]); - if (framelen & 1) { *out++ = 0; framelen++; } - FinishUDPFrame(resp, framelen); - - // TODO: if there is already a packet queued, this will overwrite it - // that being said, this will only happen during DHCP setup, so probably - // not a big deal - - PacketLen = framelen; - memcpy(PacketBuffer, resp, PacketLen); - RXNum = 1; - } -} - -void HandleDNSFrame(u8* data, int len) -{ - u8* ipheader = &data[0xE]; - u8* udpheader = &data[0x22]; - u8* dnsbody = &data[0x2A]; - - u32 srcip = ntohl(*(u32*)&ipheader[12]); - u16 srcport = ntohs(*(u16*)&udpheader[0]); - - u16 id = ntohs(*(u16*)&dnsbody[0]); - u16 flags = ntohs(*(u16*)&dnsbody[2]); - u16 numquestions = ntohs(*(u16*)&dnsbody[4]); - u16 numanswers = ntohs(*(u16*)&dnsbody[6]); - u16 numauth = ntohs(*(u16*)&dnsbody[8]); - u16 numadd = ntohs(*(u16*)&dnsbody[10]); - - printf("DNS: ID=%04X, flags=%04X, Q=%d, A=%d, auth=%d, add=%d\n", - id, flags, numquestions, numanswers, numauth, numadd); - - // for now we only take 'simple' DNS requests - if (flags & 0x8000) return; - if (numquestions != 1 || numanswers != 0) return; - - u8 resp[1024]; - u8* out = &resp[0]; - - // ethernet - memcpy(out, &data[6], 6); out += 6; - memcpy(out, kServerMAC, 6); out += 6; - *(u16*)out = htons(0x0800); out += 2; - - // IP - u8* resp_ipheader = out; - *out++ = 0x45; - *out++ = 0x00; - *(u16*)out = 0; out += 2; // total length - *(u16*)out = htons(IPv4ID); out += 2; IPv4ID++; - *out++ = 0x00; - *out++ = 0x00; - *out++ = 0x80; // TTL - *out++ = 0x11; // protocol (UDP) - *(u16*)out = 0; out += 2; // checksum - *(u32*)out = htonl(kDNSIP); out += 4; // source IP - *(u32*)out = htonl(srcip); out += 4; // destination IP - - // UDP - u8* resp_udpheader = out; - *(u16*)out = htons(53); out += 2; // source port - *(u16*)out = htons(srcport); out += 2; // destination port - *(u16*)out = 0; out += 2; // length - *(u16*)out = 0; out += 2; // checksum - - // DNS - u8* resp_body = out; - *(u16*)out = htons(id); out += 2; // ID - *(u16*)out = htons(0x8000); out += 2; // flags - *(u16*)out = htons(numquestions); out += 2; // num questions - *(u16*)out = htons(numquestions); out += 2; // num answers - *(u16*)out = 0; out += 2; // num authority - *(u16*)out = 0; out += 2; // num additional - - u32 curoffset = 12; - for (u16 i = 0; i < numquestions; i++) - { - if (curoffset >= (len-0x2A)) return; - - u8 bitlength = 0; - while ((bitlength = dnsbody[curoffset++]) != 0) - curoffset += bitlength; - - curoffset += 4; - } - - u32 qlen = curoffset-12; - if (qlen > 512) return; - memcpy(out, &dnsbody[12], qlen); out += qlen; - - curoffset = 12; - for (u16 i = 0; i < numquestions; i++) - { - // assemble the requested domain name - u8 bitlength = 0; - char domainname[256] = ""; int o = 0; - while ((bitlength = dnsbody[curoffset++]) != 0) - { - if ((o+bitlength) >= 255) - { - // welp. atleast try not to explode. - domainname[o++] = '\0'; - break; - } - - strncpy(&domainname[o], (const char *)&dnsbody[curoffset], bitlength); - o += bitlength; - - curoffset += bitlength; - if (dnsbody[curoffset] != 0) - domainname[o++] = '.'; - else - domainname[o++] = '\0'; - } - - u16 type = ntohs(*(u16*)&dnsbody[curoffset]); - u16 cls = ntohs(*(u16*)&dnsbody[curoffset+2]); - - printf("- q%d: %04X %04X %s", i, type, cls, domainname); - - // get answer - struct addrinfo dns_hint; - struct addrinfo* dns_res; - u32 addr_res; - - memset(&dns_hint, 0, sizeof(dns_hint)); - dns_hint.ai_family = AF_INET; // TODO: other address types (INET6, etc) - if (getaddrinfo(domainname, "0", &dns_hint, &dns_res) == 0) - { - struct addrinfo* p = dns_res; - while (p) - { - struct sockaddr_in* addr = (struct sockaddr_in*)p->ai_addr; - /*printf(" -> %d.%d.%d.%d", - addr->sin_addr.S_un.S_un_b.s_b1, addr->sin_addr.S_un.S_un_b.s_b2, - addr->sin_addr.S_un.S_un_b.s_b3, addr->sin_addr.S_un.S_un_b.s_b4);*/ - - //addr_res = addr->sin_addr.S_un.S_addr; - addr_res = *(u32*)&addr->sin_addr; - p = p->ai_next; - } - } - else - { - printf(" shat itself :("); - addr_res = 0; - } - - printf("\n"); - curoffset += 4; - - // TODO: betterer support - // (under which conditions does the C00C marker work?) - *(u16*)out = htons(0xC00C); out += 2; - *(u16*)out = htons(type); out += 2; - *(u16*)out = htons(cls); out += 2; - *(u32*)out = htonl(3600); out += 4; // TTL (hardcoded for now) - *(u16*)out = htons(4); out += 2; // address length - *(u32*)out = addr_res; out += 4; // address - } - - u32 framelen = (u32)(out - &resp[0]); - if (framelen & 1) { *out++ = 0; framelen++; } - FinishUDPFrame(resp, framelen); - - // TODO: if there is already a packet queued, this will overwrite it - // that being said, this will only happen during DHCP setup, so probably - // not a big deal - - PacketLen = framelen; - memcpy(PacketBuffer, resp, PacketLen); - RXNum = 1; -} - -void UDP_BuildIncomingFrame(UDPSocket* sock, u8* data, int len) -{ - u8 resp[2048]; - u8* out = &resp[0]; - - if (len > 1536) return; - - // ethernet - memcpy(out, Wifi::GetMAC(), 6); out += 6; // hurf - memcpy(out, kServerMAC, 6); out += 6; - *(u16*)out = htons(0x0800); out += 2; - - // IP - u8* resp_ipheader = out; - *out++ = 0x45; - *out++ = 0x00; - *(u16*)out = 0; out += 2; // total length - *(u16*)out = htons(IPv4ID); out += 2; IPv4ID++; - *out++ = 0x00; - *out++ = 0x00; - *out++ = 0x80; // TTL - *out++ = 0x11; // protocol (UDP) - *(u16*)out = 0; out += 2; // checksum - memcpy(out, sock->DestIP, 4); out += 4; // source IP - *(u32*)out = htonl(kClientIP); out += 4; // destination IP - - // UDP - u8* resp_tcpheader = out; - *(u16*)out = htons(sock->DestPort); out += 2; // source port - *(u16*)out = htons(sock->SourcePort); out += 2; // destination port - *(u16*)out = htons(len+8); out += 2; // length of header+data - *(u16*)out = 0; out += 2; // checksum - - memcpy(out, data, len); out += len; - - u32 framelen = (u32)(out - &resp[0]); - FinishUDPFrame(resp, framelen); - - // TODO: if there is already a packet queued, this will overwrite it - // that being said, this will only happen during DHCP setup, so probably - // not a big deal - - PacketLen = framelen; - memcpy(PacketBuffer, resp, PacketLen); - RXNum = 1; -} - -void HandleUDPFrame(u8* data, int len) -{ - u8* ipheader = &data[0xE]; - u8* udpheader = &data[0x22]; - - // debug - /*for (int j = 0; j < len; j += 16) - { - int rem = len - j; - if (rem > 16) rem = 16; - for (int i = 0; i < rem; i++) - { - printf("%02X ", data[i+j]); - } - printf("\n"); - }*/ - - u16 srcport = ntohs(*(u16*)&udpheader[0]); - u16 dstport = ntohs(*(u16*)&udpheader[2]); - - int sockid = -1; - UDPSocket* sock; - for (int i = 0; i < (sizeof(UDPSocketList)/sizeof(UDPSocket)); i++) - { - sock = &UDPSocketList[i]; - if (sock->Backend != 0 && !memcmp(&sock->DestIP, &ipheader[16], 4) && - sock->SourcePort == srcport && sock->DestPort == dstport) - { - sockid = i; - break; - } - } - - if (sockid == -1) - { - sockid = UDPSocketID; - sock = &UDPSocketList[sockid]; - - UDPSocketID++; - if (UDPSocketID >= (sizeof(UDPSocketList)/sizeof(UDPSocket))) - UDPSocketID = 0; - - if (sock->Backend != 0) - { - printf("LANMAGIC: closing previous UDP socket #%d\n", sockid); - closesocket(sock->Backend); - } - - sock->Backend = socket(AF_INET, SOCK_DGRAM, 0); - - memcpy(sock->DestIP, &ipheader[16], 4); - sock->SourcePort = srcport; - sock->DestPort = dstport; - - memset(&sock->BackendAddr, 0, sizeof(sock->BackendAddr)); - sock->BackendAddr.sin_family = AF_INET; - sock->BackendAddr.sin_port = htons(dstport); - memcpy(&sock->BackendAddr.sin_addr, &ipheader[16], 4); - /*if (bind(sock->Backend, (struct sockaddr*)&sock->BackendAddr, sizeof(sock->BackendAddr)) == -1) - { - printf("bind() shat itself :(\n"); - }*/ - - printf("LANMAGIC: opening UDP socket #%d to %d.%d.%d.%d:%d, srcport %d\n", - sockid, - ipheader[16], ipheader[17], ipheader[18], ipheader[19], - dstport, srcport); - } - - u16 udplen = ntohs(*(u16*)&udpheader[4]) - 8; - - printf("UDP: socket %d sending %d bytes\n", sockid, udplen); - sendto(sock->Backend, (char*)&udpheader[8], udplen, 0, - (struct sockaddr*)&sock->BackendAddr, sizeof(sock->BackendAddr)); -} - -void TCP_SYNACK(TCPSocket* sock, u8* data, int len) -{ - u8 resp[128]; - u8* out = &resp[0]; - - u8* ipheader = &data[0xE]; - u8* tcpheader = &data[0x22]; - - u32 seqnum = htonl(*(u32*)&tcpheader[4]); - seqnum++; - sock->AckNum = seqnum; - - //printf("SYNACK SEQ=%08X|%08X\n", sock->SeqNum, sock->AckNum); - - // ethernet - memcpy(out, &data[6], 6); out += 6; - memcpy(out, kServerMAC, 6); out += 6; - *(u16*)out = htons(0x0800); out += 2; - - // IP - u8* resp_ipheader = out; - *out++ = 0x45; - *out++ = 0x00; - *(u16*)out = 0; out += 2; // total length - *(u16*)out = htons(IPv4ID); out += 2; IPv4ID++; - *out++ = 0x00; - *out++ = 0x00; - *out++ = 0x80; // TTL - *out++ = 0x06; // protocol (TCP) - *(u16*)out = 0; out += 2; // checksum - *(u32*)out = *(u32*)&ipheader[16]; out += 4; // source IP - *(u32*)out = *(u32*)&ipheader[12]; out += 4; // destination IP - - // TCP - u8* resp_tcpheader = out; - *(u16*)out = *(u16*)&tcpheader[2]; out += 2; // source port - *(u16*)out = *(u16*)&tcpheader[0]; out += 2; // destination port - *(u32*)out = htonl(sock->SeqNum); out += 4; sock->SeqNum++; // seq number - *(u32*)out = htonl(seqnum); out += 4; // ack seq number - *(u16*)out = htons(0x8012); out += 2; // flags (SYN+ACK) - *(u16*)out = htons(0x7000); out += 2; // window size (uuuh) - *(u16*)out = 0; out += 2; // checksum - *(u16*)out = 0; out += 2; // urgent pointer - - // TCP options - *out++ = 0x02; *out++ = 0x04; // max segment size - *(u16*)out = htons(0x05B4); out += 2; - *out++ = 0x01; - *out++ = 0x01; - *out++ = 0x04; *out++ = 0x02; // SACK permitted - *out++ = 0x01; - *out++ = 0x03; *out++ = 0x03; // window size - *out++ = 0x08; - - u32 framelen = (u32)(out - &resp[0]); - //if (framelen & 1) { *out++ = 0; framelen++; } - FinishTCPFrame(resp, framelen); - - // TODO: if there is already a packet queued, this will overwrite it - // that being said, this will only happen during DHCP setup, so probably - // not a big deal - - PacketLen = framelen; - memcpy(PacketBuffer, resp, PacketLen); - RXNum = 1; -} - -void TCP_ACK(TCPSocket* sock, bool fin) -{ - u8 resp[64]; - u8* out = &resp[0]; - - u16 flags = 0x5010; - if (fin) flags |= 0x0001; - - //printf("%sACK SEQ=%08X|%08X\n", fin?"FIN":" ", sock->SeqNum, sock->AckNum); - - // ethernet - memcpy(out, Wifi::GetMAC(), 6); out += 6; - memcpy(out, kServerMAC, 6); out += 6; - *(u16*)out = htons(0x0800); out += 2; - - // IP - u8* resp_ipheader = out; - *out++ = 0x45; - *out++ = 0x00; - *(u16*)out = 0; out += 2; // total length - *(u16*)out = htons(IPv4ID); out += 2; IPv4ID++; - *out++ = 0x00; - *out++ = 0x00; - *out++ = 0x80; // TTL - *out++ = 0x06; // protocol (TCP) - *(u16*)out = 0; out += 2; // checksum - *(u32*)out = *(u32*)&sock->DestIP; out += 4; // source IP - *(u32*)out = htonl(kClientIP); out += 4; // destination IP - - // TCP - u8* resp_tcpheader = out; - *(u16*)out = htonl(sock->DestPort); out += 2; // source port - *(u16*)out = htonl(sock->SourcePort); out += 2; // destination port - *(u32*)out = htonl(sock->SeqNum); out += 4; // seq number - *(u32*)out = htonl(sock->AckNum); out += 4; // ack seq number - *(u16*)out = htons(flags); out += 2; // flags - *(u16*)out = htons(0x7000); out += 2; // window size (uuuh) - *(u16*)out = 0; out += 2; // checksum - *(u16*)out = 0; out += 2; // urgent pointer - - u32 framelen = (u32)(out - &resp[0]); - //if (framelen & 1) { *out++ = 0; framelen++; } - FinishTCPFrame(resp, framelen); - - // TODO: if there is already a packet queued, this will overwrite it - // that being said, this will only happen during DHCP setup, so probably - // not a big deal - - PacketLen = framelen; - memcpy(PacketBuffer, resp, PacketLen); - RXNum = 1; -} - -void TCP_BuildIncomingFrame(TCPSocket* sock, u8* data, int len) -{ - u8 resp[2048]; - u8* out = &resp[0]; - - if (len > 1536) return; -//printf("INCOMING SEQ=%08X|%08X\n", sock->SeqNum, sock->AckNum); - // ethernet - memcpy(out, Wifi::GetMAC(), 6); out += 6; // hurf - memcpy(out, kServerMAC, 6); out += 6; - *(u16*)out = htons(0x0800); out += 2; - - // IP - u8* resp_ipheader = out; - *out++ = 0x45; - *out++ = 0x00; - *(u16*)out = 0; out += 2; // total length - *(u16*)out = htons(IPv4ID); out += 2; IPv4ID++; - *out++ = 0x00; - *out++ = 0x00; - *out++ = 0x80; // TTL - *out++ = 0x06; // protocol (TCP) - *(u16*)out = 0; out += 2; // checksum - memcpy(out, sock->DestIP, 4); out += 4; // source IP - *(u32*)out = htonl(kClientIP); out += 4; // destination IP - - // TCP - u8* resp_tcpheader = out; - *(u16*)out = htons(sock->DestPort); out += 2; // source port - *(u16*)out = htons(sock->SourcePort); out += 2; // destination port - *(u32*)out = htonl(sock->SeqNum); out += 4; // seq number - *(u32*)out = htonl(sock->AckNum); out += 4; // ack seq number - *(u16*)out = htons(0x5018); out += 2; // flags (ACK, PSH) - *(u16*)out = htons(0x7000); out += 2; // window size (uuuh) - *(u16*)out = 0; out += 2; // checksum - *(u16*)out = 0; out += 2; // urgent pointer - - memcpy(out, data, len); out += len; - - u32 framelen = (u32)(out - &resp[0]); - FinishTCPFrame(resp, framelen); - - // TODO: if there is already a packet queued, this will overwrite it - // that being said, this will only happen during DHCP setup, so probably - // not a big deal - - PacketLen = framelen; - memcpy(PacketBuffer, resp, PacketLen); - RXNum = 1; - - sock->SeqNum += len; -} - -void HandleTCPFrame(u8* data, int len) -{ - u8* ipheader = &data[0xE]; - u8* tcpheader = &data[0x22]; - - u16 srcport = ntohs(*(u16*)&tcpheader[0]); - u16 dstport = ntohs(*(u16*)&tcpheader[2]); - u16 flags = ntohs(*(u16*)&tcpheader[12]); - - u32 tcpheaderlen = 4 * (flags >> 12); - u32 tcplen = ntohs(*(u16*)&ipheader[2]) - 0x14; - u32 tcpdatalen = tcplen - tcpheaderlen; - - /*printf("tcpflags=%04X header=%d data=%d seq=%08X|%08X\n", - flags, tcpheaderlen, tcpdatalen, - ntohl(*(u32*)&tcpheader[4]), - ntohl(*(u32*)&tcpheader[8]));*/ - - if (flags & 0x002) // SYN - { - int sockid = -1; - TCPSocket* sock; - for (int i = 0; i < (sizeof(TCPSocketList)/sizeof(TCPSocket)); i++) - { - sock = &TCPSocketList[i]; - if (sock->Status != 0 && !memcmp(&sock->DestIP, &ipheader[16], 4) && - sock->SourcePort == srcport && sock->DestPort == dstport) - { - printf("LANMAGIC: duplicate TCP socket\n"); - sockid = i; - break; - } - } - - if (sockid == -1) - { - for (int i = 0; i < (sizeof(TCPSocketList)/sizeof(TCPSocket)); i++) - { - sock = &TCPSocketList[i]; - if (sock->Status == 0) - { - sockid = i; - break; - } - } - } - - if (sockid == -1) - { - printf("LANMAGIC: !! TCP SOCKET LIST FULL\n"); - return; - } - - printf("LANMAGIC: opening TCP socket #%d to %d.%d.%d.%d:%d, srcport %d\n", - sockid, - ipheader[16], ipheader[17], ipheader[18], ipheader[19], - dstport, srcport); - - // keep track of it - sock->Status = 1; - memcpy(sock->DestIP, &ipheader[16], 4); - sock->DestPort = dstport; - sock->SourcePort = srcport; - sock->SeqNum = 0x13370000; - sock->AckNum = 0; - - // open backend socket - if (!sock->Backend) - { - sock->Backend = socket(AF_INET, SOCK_STREAM, 0); - } - - struct sockaddr_in conn_addr; - memset(&conn_addr, 0, sizeof(conn_addr)); - conn_addr.sin_family = AF_INET; - memcpy(&conn_addr.sin_addr, &ipheader[16], 4); - conn_addr.sin_port = htons(dstport); - if (connect(sock->Backend, (sockaddr*)&conn_addr, sizeof(conn_addr)) == -1) - { - printf("connect() shat itself :(\n"); - } - else - { - // acknowledge it - TCP_SYNACK(sock, data, len); - } - } - else - { - int sockid = -1; - TCPSocket* sock; - for (int i = 0; i < (sizeof(TCPSocketList)/sizeof(TCPSocket)); i++) - { - sock = &TCPSocketList[i]; - if (sock->Status != 0 && !memcmp(&sock->DestIP, &ipheader[16], 4) && - sock->SourcePort == srcport && sock->DestPort == dstport) - { - sockid = i; - break; - } - } - - if (sockid == -1) - { - printf("LANMAGIC: bad TCP packet\n"); - return; - } - - // TODO: check those - u32 seqnum = ntohl(*(u32*)&tcpheader[4]); - u32 acknum = ntohl(*(u32*)&tcpheader[8]); - sock->SeqNum = acknum; - sock->AckNum = seqnum + tcpdatalen; - - // send data over the socket - if (tcpdatalen > 0) - { - u8* tcpdata = &tcpheader[tcpheaderlen]; - - printf("TCP: socket %d sending %d bytes (flags=%04X)\n", sockid, tcpdatalen, flags); - send(sock->Backend, (char*)tcpdata, tcpdatalen, 0); - - // kind of a hack, there - TCP_ACK(sock, false); - } - - if (flags & 0x001) // FIN - { - // TODO: timeout etc - printf("TCP: socket %d closing\n", sockid); - - sock->Status = 0; - closesocket(sock->Backend); - sock->Backend = 0; - } - } -} - -void HandleARPFrame(u8* data, int len) -{ - u16 protocol = ntohs(*(u16*)&data[0x10]); - if (protocol != 0x0800) return; - - u16 op = ntohs(*(u16*)&data[0x14]); - u32 targetip = ntohl(*(u32*)&data[0x26]); - - // TODO: handle ARP to the client - // this only handles ARP to the DHCP/router - - if (op == 1) - { - // opcode 1=req 2=reply - // sender MAC - // sender IP - // target MAC - // target IP - - const u8* targetmac; - if (targetip == kServerIP) targetmac = kServerMAC; - else if (targetip == kDNSIP) targetmac = kDNSMAC; - else return; - - u8 resp[64]; - u8* out = &resp[0]; - - // ethernet - memcpy(out, &data[6], 6); out += 6; - memcpy(out, kServerMAC, 6); out += 6; - *(u16*)out = htons(0x0806); out += 2; - - // ARP - *(u16*)out = htons(0x0001); out += 2; // hardware type - *(u16*)out = htons(0x0800); out += 2; // protocol - *out++ = 6; // MAC address size - *out++ = 4; // IP address size - *(u16*)out = htons(0x0002); out += 2; // opcode - memcpy(out, targetmac, 6); out += 6; - *(u32*)out = htonl(targetip); out += 4; - memcpy(out, &data[0x16], 6+4); out += 6+4; - - u32 framelen = (u32)(out - &resp[0]); - - // TODO: if there is already a packet queued, this will overwrite it - // that being said, this will only happen during DHCP setup, so probably - // not a big deal - - PacketLen = framelen; - memcpy(PacketBuffer, resp, PacketLen); - RXNum = 1; - } - else - { - printf("wat??\n"); - } -} - -void HandlePacket(u8* data, int len) -{ - u16 ethertype = ntohs(*(u16*)&data[0xC]); - - if (ethertype == 0x0800) // IPv4 - { - u8 protocol = data[0x17]; - if (protocol == 0x11) // UDP - { - u16 srcport = ntohs(*(u16*)&data[0x22]); - u16 dstport = ntohs(*(u16*)&data[0x24]); - if (srcport == 68 && dstport == 67) // DHCP - { - printf("LANMAGIC: DHCP packet\n"); - return HandleDHCPFrame(data, len); - } - else if (dstport == 53 && htonl(*(u32*)&data[0x1E]) == kDNSIP) // DNS - { - printf("LANMAGIC: DNS packet\n"); - return HandleDNSFrame(data, len); - } - - printf("LANMAGIC: UDP packet %d->%d\n", srcport, dstport); - return HandleUDPFrame(data, len); - } - else if (protocol == 0x06) // TCP - { - printf("LANMAGIC: TCP packet\n"); - return HandleTCPFrame(data, len); - } - else - printf("LANMAGIC: unsupported IP protocol %02X\n", protocol); - } - else if (ethertype == 0x0806) // ARP - { - printf("LANMAGIC: ARP packet\n"); - return HandleARPFrame(data, len); - } - else - printf("LANMAGIC: unsupported ethernet type %04X\n", ethertype); -} - -int SendPacket(u8* data, int len) -{ - if (len > 2048) - { - printf("LAN_SendPacket: error: packet too long (%d)\n", len); - return 0; - } - - HandlePacket(data, len); - return len; -} - -int RecvPacket(u8* data) -{ - int ret = 0; - if (RXNum > 0) - { - memcpy(data, PacketBuffer, PacketLen); - ret = PacketLen; - RXNum = 0; - } - - for (int i = 0; i < (sizeof(TCPSocketList)/sizeof(TCPSocket)); i++) - { - TCPSocket* sock = &TCPSocketList[i]; - if (sock->Status != 1) continue; - - fd_set fd; - struct timeval tv; - - FD_ZERO(&fd); - FD_SET(sock->Backend, &fd); - tv.tv_sec = 0; - tv.tv_usec = 0; - - if (!select(sock->Backend+1, &fd, 0, 0, &tv)) - { - continue; - } - - u8 recvbuf[1024]; - int recvlen = recv(sock->Backend, (char*)recvbuf, 1024, 0); - if (recvlen < 1) - { - if (recvlen == 0) - { - // socket has closed from the other side - printf("TCP: socket %d closed from other side\n", i); - sock->Status = 2; - TCP_ACK(sock, true); - } - continue; - } - - printf("TCP: socket %d receiving %d bytes\n", i, recvlen); - TCP_BuildIncomingFrame(sock, recvbuf, recvlen); - - // debug - /*for (int j = 0; j < recvlen; j += 16) - { - int rem = recvlen - j; - if (rem > 16) rem = 16; - for (int k = 0; k < rem; k++) - { - printf("%02X ", recvbuf[k+j]); - } - printf("\n"); - }*/ - - //recvlen = recv(sock->Backend, (char*)recvbuf, 1024, 0); - //if (recvlen == 0) printf("it closed immediately after\n"); - } - - for (int i = 0; i < (sizeof(UDPSocketList)/sizeof(UDPSocket)); i++) - { - UDPSocket* sock = &UDPSocketList[i]; - if (sock->Backend == 0) continue; - - fd_set fd; - struct timeval tv; - - FD_ZERO(&fd); - FD_SET(sock->Backend, &fd); - tv.tv_sec = 0; - tv.tv_usec = 0; - - if (!select(sock->Backend+1, &fd, 0, 0, &tv)) - { - continue; - } - - u8 recvbuf[1024]; - sockaddr_t fromAddr; - socklen_t fromLen = sizeof(sockaddr_t); - int recvlen = recvfrom(sock->Backend, (char*)recvbuf, 1024, 0, &fromAddr, &fromLen); - if (recvlen < 1) continue; - - if (fromAddr.sa_family != AF_INET) continue; - struct sockaddr_in* fromAddrIn = (struct sockaddr_in*)&fromAddr; - if (memcmp(&fromAddrIn->sin_addr, sock->DestIP, 4)) continue; - if (ntohs(fromAddrIn->sin_port) != sock->DestPort) continue; - - printf("UDP: socket %d receiving %d bytes\n", i, recvlen); - UDP_BuildIncomingFrame(sock, recvbuf, recvlen); - } - - return ret; -} - -} |