/* network.h * * Functions for the core networking. * * Copyright (C) 2013 Tox project All Rights Reserved. * * This file is part of Tox. * * Tox 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. * * Tox 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 Tox. If not, see . * */ #include "network.h" /* returns current UNIX time in microseconds (us). */ uint64_t current_time(void) { uint64_t time; #ifdef WIN32 /* This probably works fine */ FILETIME ft; GetSystemTimeAsFileTime(&ft); time = ft.dwHighDateTime; time <<= 32; time |= ft.dwLowDateTime; time -= 116444736000000000UL; return time / 10; #else struct timeval a; gettimeofday(&a, NULL); time = 1000000UL * a.tv_sec + a.tv_usec; return time; #endif } /* return a random number NOTE: this function should probably not be used where cryptographic randomness is absolutely necessary */ uint32_t random_int(void) { #ifndef VANILLA_NACL //NOTE: this function comes from libsodium return randombytes_random(); #else return random(); #endif } /* Basic network functions: Function to send packet(data) of length length to ip_port */ int sendpacket(int sock, IP_Port ip_port, uint8_t *data, uint32_t length) { ADDR addr = {AF_INET, ip_port.port, ip_port.ip}; return sendto(sock, (char *) data, length, 0, (struct sockaddr *)&addr, sizeof(addr)); } /* Function to receive data, ip and port of sender is put into ip_port the packet data into data the packet length into length. dump all empty packets. */ static int receivepacket(int sock, IP_Port *ip_port, uint8_t *data, uint32_t *length) { ADDR addr; #ifdef WIN32 int addrlen = sizeof(addr); #else uint32_t addrlen = sizeof(addr); #endif (*(int32_t *)length) = recvfrom(sock, (char *) data, MAX_UDP_PACKET_SIZE, 0, (struct sockaddr *)&addr, &addrlen); if (*(int32_t *)length <= 0) return -1; /* nothing received or empty packet */ ip_port->ip = addr.ip; ip_port->port = addr.port; return 0; } void networking_registerhandler(Networking_Core *net, uint8_t byte, packet_handler_callback cb, void *object) { net->packethandlers[byte].function = cb; net->packethandlers[byte].object = object; } void networking_poll(Networking_Core *net) { IP_Port ip_port; uint8_t data[MAX_UDP_PACKET_SIZE]; uint32_t length; while (receivepacket(net->sock, &ip_port, data, &length) != -1) { if (length < 1) continue; if (!(net->packethandlers[data[0]].function)) continue; net->packethandlers[data[0]].function(net->packethandlers[data[0]].object, ip_port, data, length); } } uint8_t at_startup_ran; static void at_startup(void) { if (at_startup_ran != 0) return; #ifdef WIN32 WSADATA wsaData; if (WSAStartup(MAKEWORD(2, 2), &wsaData) != NO_ERROR) return -1; #else srandom((uint32_t)current_time()); #endif srand((uint32_t)current_time()); at_startup_ran = 1; } /* TODO: put this somewhere static void at_shutdown(void) { #ifdef WIN32 WSACleanup(); #endif } */ /* initialize networking bind to ip and port ip must be in network order EX: 127.0.0.1 = (7F000001) port is in host byte order (this means don't worry about it) returns Networking_Core object if no problems returns NULL if there are problems */ Networking_Core *new_networking(IP ip, uint16_t port) { at_startup(); /* initialize our socket */ Networking_Core *temp = calloc(1, sizeof(Networking_Core)); if (temp == NULL) return NULL; temp->sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); /* Check for socket error */ #ifdef WIN32 if (temp->sock == INVALID_SOCKET) { /* MSDN recommends this */ free(temp); return NULL; } #else if (temp->sock < 0) { free(temp); return NULL; } #endif /* Functions to increase the size of the send and receive UDP buffers NOTE: uncomment if necessary */ /* int n = 1024 * 1024 * 2; if(setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (char*)&n, sizeof(n)) == -1) { return -1; } if(setsockopt(sock, SOL_SOCKET, SO_SNDBUF, (char*)&n, sizeof(n)) == -1) return -1; */ /* Enable broadcast on socket */ int broadcast = 1; setsockopt(temp->sock, SOL_SOCKET, SO_BROADCAST, (char *)&broadcast, sizeof(broadcast)); /* Set socket nonblocking */ #ifdef WIN32 /* I think this works for windows */ u_long mode = 1; /* ioctl(sock, FIONBIO, &mode); */ ioctlsocket(temp->sock, FIONBIO, &mode); #else fcntl(temp->sock, F_SETFL, O_NONBLOCK, 1); #endif /* Bind our socket to port PORT and address 0.0.0.0 */ ADDR addr = {AF_INET, htons(port), ip}; bind(temp->sock, (struct sockaddr *)&addr, sizeof(addr)); return temp; } /* function to cleanup networking stuff */ void kill_networking(Networking_Core *net) { #ifdef WIN32 closesocket(net->sock); #else close(net->sock); #endif free(net); return; } /* resolve_addr(): address should represent IPv4 or a hostname with A record returns a data in network byte order that can be used to set IP.i or IP_Port.ip.i returns 0 on failure TODO: Fix ipv6 support */ uint32_t resolve_addr(const char *address) { struct addrinfo *server = NULL; struct addrinfo hints; int rc; uint32_t addr; memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_INET; // IPv4 only right now. hints.ai_socktype = SOCK_DGRAM; // type of socket Tox uses. rc = getaddrinfo(address, "echo", &hints, &server); // Lookup failed. if (rc != 0) { return 0; } // IPv4 records only.. if (server->ai_family != AF_INET) { freeaddrinfo(server); return 0; } addr = ((struct sockaddr_in *)server->ai_addr)->sin_addr.s_addr; freeaddrinfo(server); return addr; }