#include "main.h" #include "client.h" #include "tox_bootstrap.h" static Tox_Options tox_options; Tox *tox; int client_socket = 0; /** CONFIGURATION OPTIONS **/ /* Whether we're a client */ int client_mode = 0; /* Just send a ping and exit */ int ping_mode = 0; /* Open a local port and forward it */ int client_local_port_mode = 0; /* Forward stdin/stdout to remote machine - SSH ProxyCommand mode */ int client_pipe_mode = 0; /* Remote Tox ID in client mode */ char *remote_tox_id = NULL; /* Directory with config and tox save */ char config_path[500] = "/etc/tuntox/"; /* Ports and hostname for port forwarding */ int remote_port = 0; char *remote_host = NULL; int local_port = 0; fd_set master_server_fds; /* We keep two hash tables: one indexed by sockfd and another by "connection id" */ tunnel *by_id = NULL; /* Highest used fd + 1 for select() */ int select_nfds = 4; /* Generate an unique tunnel ID. To be used in a server. */ uint16_t get_random_tunnel_id() { while(1) { int key; uint16_t tunnel_id; tunnel *tun; tunnel_id = (uint16_t)rand(); key = tunnel_id; HASH_FIND_INT(by_id, &key, tun); if(!tun) { return tunnel_id; } fprintf(stderr, "[i] Found duplicated tunnel ID %d\n", key); } } void update_select_nfds(int fd) { /* TODO maybe replace with a scan every time to make select() more efficient in the long run? */ if(fd + 1 > select_nfds) { select_nfds = fd + 1; } } /* Constructor. Returns NULL on failure. */ tunnel *tunnel_create(int sockfd, int connid, uint32_t friendnumber) { tunnel *t = NULL; t = calloc(1, sizeof(tunnel)); if(!t) { return NULL; } t->sockfd = sockfd; t->connid = connid; t->friendnumber = friendnumber; fprintf(stderr, "Created a new tunnel object connid=%d sockfd=%d\n", connid, sockfd); update_select_nfds(t->sockfd); HASH_ADD_INT( by_id, connid, t ); return t; } void tunnel_delete(tunnel *t) { fprintf(stderr, "Deleting tunnel #%d\n", t->connid); if(t->sockfd) { close(t->sockfd); } HASH_DEL( by_id, t ); free(t); } /* bootstrap to dht with bootstrap_nodes */ /* From uTox/tox.c */ static void do_bootstrap(Tox *tox) { static unsigned int j = 0; if (j == 0) j = rand(); int i = 0; while(i < 4) { struct bootstrap_node *d = &bootstrap_nodes[j % countof(bootstrap_nodes)]; tox_bootstrap_from_address(tox, d->address, d->port, d->key); i++; j++; } } /* Set username to the machine's FQDN */ void set_tox_username(Tox *tox) { unsigned char hostname[1024]; struct addrinfo hints, *info, *p; int gai_result; gethostname(hostname, 1024); hostname[1023] = '\0'; tox_set_name(tox, hostname, strlen(hostname)); } /* Get sockaddr, IPv4 or IPv6 */ void *get_in_addr(struct sockaddr *sa) { if (sa->sa_family == AF_INET) { return &(((struct sockaddr_in*)sa)->sin_addr); } return &(((struct sockaddr_in6*)sa)->sin6_addr); } int get_client_socket(char *hostname, int port) { int sockfd, numbytes; char buf[READ_BUFFER_SIZE]; struct addrinfo hints, *servinfo, *p; int rv; char s[INET6_ADDRSTRLEN]; char port_str[6]; snprintf(port_str, 6, "%d", port); memset(&hints, 0, sizeof hints); hints.ai_family = AF_INET; hints.ai_socktype = SOCK_STREAM; if ((rv = getaddrinfo(hostname, port_str, &hints, &servinfo)) != 0) { /* Add a special case for "localhost" when name resolution is broken */ if(!strncmp("localhost", hostname, 256)) { const char localhostname[] = "127.0.0.1"; if ((rv = getaddrinfo(localhostname, port_str, &hints, &servinfo)) != 0) { fprintf(stderr, "getaddrinfo failed for 127.0.0.1: %s\n", gai_strerror(rv)); return -1; } } else { fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv)); return -1; } } // loop through all the results and connect to the first we can for(p = servinfo; p != NULL; p = p->ai_next) { if (p->ai_family != AF_INET && p->ai_family != AF_INET6) continue; if ((sockfd = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == -1) { perror("client: socket"); continue; } if (connect(sockfd, p->ai_addr, p->ai_addrlen) == -1) { close(sockfd); perror("client: connect"); continue; } break; } if (p == NULL) { fprintf(stderr, "failed to connect to %s:%d\n", hostname, port); return -1; } inet_ntop(p->ai_family, get_in_addr((struct sockaddr *)p->ai_addr), s, sizeof s); fprintf(stderr, "connecting to %s\n", s); freeaddrinfo(servinfo); // all done with this structure fprintf(stderr, "Connected to %s:%d\n", hostname, port); return sockfd; } /* Proto - our protocol handling */ /* * send_frame: (almost) zero-copy. Overwrites first PROTOCOL_BUFFER_OFFSET bytes of data * so actual data should start at position PROTOCOL_BUFFER_OFFSET */ int send_frame(protocol_frame *frame, uint8_t *data) { int rv = -1; int try = 0; int i; data[0] = PROTOCOL_MAGIC_HIGH; data[1] = PROTOCOL_MAGIC_LOW; data[2] = BYTE2(frame->packet_type); data[3] = BYTE1(frame->packet_type); data[4] = BYTE2(frame->connid); data[5] = BYTE1(frame->connid); data[6] = BYTE2(frame->data_length); data[7] = BYTE1(frame->data_length); for(i = 0; i < 65;) /* 1.27 seconds per packet max */ { int j; try++; rv = tox_send_lossless_packet( tox, frame->friendnumber, data, frame->data_length + PROTOCOL_BUFFER_OFFSET ); if(rv < 0) { /* If this branch is ran, most likely we've hit congestion control. */ fprintf(stderr, "[%d] Failed to send packet to friend %d\n", i, frame->friendnumber); } else { break; } if(i == 0) i = 2; else i = i * 2; for(j = 0; j < i; j++) { tox_do(tox); usleep(j * 10000); } } if(i > 0 && rv >= 0) { fprintf(stderr, "Packet succeeded at try %d\n", try); } return rv; } int send_tunnel_ack_frame(tunnel *tun) { protocol_frame frame_st; protocol_frame *frame; char data[PROTOCOL_BUFFER_OFFSET]; frame = &frame_st; memset(frame, 0, sizeof(protocol_frame)); frame->packet_type = PACKET_TYPE_ACKTUNNEL; frame->connid = tun->connid; frame->data_length = 0; frame->friendnumber = tun->friendnumber; return send_frame(frame, data); } int handle_ping_frame(protocol_frame *rcvd_frame) { uint8_t data[TOX_MAX_CUSTOM_PACKET_SIZE]; protocol_frame frame_s; protocol_frame *frame = &frame_s; frame->data = data + PROTOCOL_BUFFER_OFFSET; memcpy(frame->data, rcvd_frame->data, rcvd_frame->data_length); frame->friendnumber = rcvd_frame->friendnumber; frame->packet_type = PACKET_TYPE_PONG; frame->data_length = rcvd_frame->data_length; send_frame(frame, data); } int handle_request_tunnel_frame(protocol_frame *rcvd_frame) { char *hostname = NULL; tunnel *tun; int port = -1; int sockfd = 0; uint16_t tunnel_id; if(client_mode) { fprintf(stderr, "Got tunnel request frame from friend #%d when in client mode\n", rcvd_frame->friendnumber); return -1; } port = rcvd_frame->connid; hostname = calloc(1, rcvd_frame->data_length + 1); if(!hostname) { fprintf(stderr, "Could not allocate memory for tunnel request hostname\n"); return -1; } strncpy(hostname, rcvd_frame->data, rcvd_frame->data_length); hostname[rcvd_frame->data_length] = '\0'; fprintf(stderr, "Got a request to forward data from %s:%d\n", hostname, port); tunnel_id = get_random_tunnel_id(); fprintf(stderr, "Tunnel ID: %d\n", tunnel_id); /* TODO make connection */ sockfd = get_client_socket(hostname, port); if(sockfd > 0) { tun = tunnel_create(sockfd, tunnel_id, rcvd_frame->friendnumber); if(tun) { FD_SET(sockfd, &master_server_fds); update_select_nfds(sockfd); fprintf(stderr, "Created tunnel, yay!\n"); send_tunnel_ack_frame(tun); } else { fprintf(stderr, "Couldn't allocate memory for tunnel\n"); } } else { fprintf(stderr, "Could not connect to %s:%d\n", hostname, port); /* TODO send reject */ } } /* Handle a TCP frame received from client */ int handle_client_tcp_frame(protocol_frame *rcvd_frame) { tunnel *tun=NULL; int offset = 0; int connid = rcvd_frame->connid; HASH_FIND_INT(by_id, &connid, tun); if(!tun) { fprintf(stderr, "Got TCP frame with unknown tunnel ID %d\n", rcvd_frame->connid); return -1; } if(tun->friendnumber != rcvd_frame->friendnumber) { fprintf(stderr, "Friend #%d tried to send packet to a tunnel which belongs to #%d\n", rcvd_frame->friendnumber, tun->friendnumber); return -1; } while(offset < rcvd_frame->data_length) { int sent_bytes; sent_bytes = send( tun->sockfd, rcvd_frame->data + offset, rcvd_frame->data_length - offset, MSG_NOSIGNAL ); if(sent_bytes < 0) { fprintf(stderr, "Could not write to socket %d: %s\n", tun->sockfd, strerror(errno)); return -1; } offset += sent_bytes; } return 0; } /* Handle close-tunnel frame received from the client */ int handle_client_tcp_fin_frame(protocol_frame *rcvd_frame) { tunnel *tun=NULL; int offset = 0; int connid = rcvd_frame->connid; HASH_FIND_INT(by_id, &connid, tun); if(!tun) { fprintf(stderr, "Got TCP FIN frame with unknown tunnel ID %d\n", rcvd_frame->connid); return -1; } if(tun->friendnumber != rcvd_frame->friendnumber) { fprintf(stderr, "Friend #%d tried to close tunnel which belongs to #%d\n", rcvd_frame->friendnumber, tun->friendnumber); return -1; } tunnel_delete(tun); } /* This is a dispatcher for our encapsulated protocol */ int handle_frame(protocol_frame *frame) { switch(frame->packet_type) { case PACKET_TYPE_PING: return handle_ping_frame(frame); break; case PACKET_TYPE_PONG: return handle_pong_frame(frame); break; case PACKET_TYPE_TCP: if(client_mode) { return handle_server_tcp_frame(frame); } else { return handle_client_tcp_frame(frame); } break; case PACKET_TYPE_REQUESTTUNNEL: handle_request_tunnel_frame(frame); break; case PACKET_TYPE_ACKTUNNEL: handle_acktunnel_frame(frame); break; case PACKET_TYPE_TCP_FIN: if(client_mode) { return handle_server_tcp_fin_frame(frame); } else { return handle_client_tcp_fin_frame(frame); } break; default: fprintf(stderr, "Got unknown packet type 0x%x from friend %d\n", frame->packet_type, frame->friendnumber ); } return 0; } /* * This is a callback which gets a packet from Tox core. * It checks for basic inconsistiencies and allocates the * protocol_frame structure. */ int parse_lossless_packet(Tox *tox, int32_t friendnumber, const uint8_t *data, uint32_t len, void *sender_uc) { protocol_frame *frame = NULL; if(len < PROTOCOL_BUFFER_OFFSET) { fprintf(stderr, "Received too short data frame - only %d bytes, at least %d expected\n", len, PROTOCOL_BUFFER_OFFSET); return -1; } /* if(!data) { fprintf(stderr, "Got NULL pointer from toxcore - WTF?\n"); return -1; } */ if(data[0] != PROTOCOL_MAGIC_HIGH || data[1] != PROTOCOL_MAGIC_LOW) { fprintf(stderr, "Received data frame with invalid protocol magic number 0x%x%x\n", data[0], data[1]); return -1; } frame = calloc(1, sizeof(protocol_frame)); if(!frame) { fprintf(stderr, "Could not allocate memory for protocol_frame_t\n"); return -1; } /* TODO check if friendnumber is the same in sender and connid tunnel*/ frame->magic = INT16_AT(data, 0); frame->packet_type = INT16_AT(data, 2); frame->connid = INT16_AT(data, 4); frame->data_length = INT16_AT(data, 6); frame->data = (uint8_t *)(data + PROTOCOL_BUFFER_OFFSET); frame->friendnumber = *((uint32_t*)sender_uc); fprintf(stderr, "Got protocol frame magic 0x%x type 0x%x from friend %d\n", frame->magic, frame->packet_type, frame->friendnumber); if(len < frame->data_length + PROTOCOL_BUFFER_OFFSET) { fprintf(stderr, "Received frame too small (attempted buffer overflow?): %d bytes, excepted at least %d bytes\n", len, frame->data_length + PROTOCOL_BUFFER_OFFSET); return -1; } if(frame->data_length > (TOX_MAX_CUSTOM_PACKET_SIZE - PROTOCOL_BUFFER_OFFSET)) { fprintf(stderr, "Declared data length too big (attempted buffer overflow?): %d bytes, excepted at most %d bytes\n", frame->data_length, (TOX_MAX_CUSTOM_PACKET_SIZE - PROTOCOL_BUFFER_OFFSET)); return -1; } handle_frame(frame); } int send_tunnel_request_packet(char *remote_host, int remote_port, int friend_number) { int packet_length = 0; protocol_frame frame_i, *frame; char *data = NULL; fprintf(stderr, "Sending packet to friend #%d to forward %s:%d\n", friend_number, remote_host, remote_port); packet_length = PROTOCOL_BUFFER_OFFSET + strlen(remote_host); frame = &frame_i; data = calloc(1, packet_length); if(!data) { fprintf(stderr, "Could not allocate memory for tunnel request packet\n"); exit(1); } strcpy(data+PROTOCOL_BUFFER_OFFSET, remote_host); frame->friendnumber = friend_number; frame->packet_type = PACKET_TYPE_REQUESTTUNNEL; frame->connid = remote_port; frame->data_length = strlen(remote_host); send_frame(frame, data); free(data); return 0; } /* End proto */ /* Save tox identity to a file */ static void write_save(Tox *tox) { void *data; uint32_t size; uint8_t path_tmp[512], path_real[512], *p; FILE *file; size = tox_size(tox); data = malloc(size); tox_save(tox, data); strncpy(path_real, config_path, sizeof(config_path)); p = path_real + strlen(path_real); memcpy(p, "tox_save", sizeof("tox_save")); unsigned int path_len = (p - path_real) + sizeof("tox_save"); memcpy(path_tmp, path_real, path_len); memcpy(path_tmp + (path_len - 1), ".tmp", sizeof(".tmp")); file = fopen((char*)path_tmp, "wb"); if(file) { fwrite(data, size, 1, file); fflush(file); fclose(file); if (rename((char*)path_tmp, (char*)path_real) != 0) { fprintf(stderr, "Failed to rename file. %s to %s deleting and trying again\n", path_tmp, path_real); remove((const char *)path_real); if (rename((char*)path_tmp, (char*)path_real) != 0) { fprintf(stderr, "Saving Failed\n"); } else { fprintf(stderr, "Saved data\n"); } } else { fprintf(stderr, "Saved data\n"); } } else { fprintf(stderr, "Could not open save file\n"); } free(data); } /* Load tox identity from a file */ static int load_save(Tox *tox) { void *data; uint32_t size; uint8_t path_tmp[512], path_real[512], *p; FILE *file; strncpy(path_real, config_path, sizeof(config_path)); p = path_real + strlen(path_real); memcpy(p, "tox_save", sizeof("tox_save")); unsigned int path_len = (p - path_real) + sizeof("tox_save"); data = file_raw((char *)path_real, &size); if(data) { tox_load(tox, data, size); free(data); return 1; } else { fprintf(stderr, "Could not open save file\n"); return 0; } } void accept_friend_request(Tox *tox, const uint8_t *public_key, const uint8_t *data, uint16_t length, void *userdata) { unsigned char tox_printable_id[TOX_FRIEND_ADDRESS_SIZE * 2 + 1]; int32_t friendnumber; int32_t *friendnumber_ptr = NULL; fprintf(stderr, "Got friend request\n"); friendnumber = tox_add_friend_norequest(tox, public_key); memset(tox_printable_id, '\0', sizeof(tox_printable_id)); id_to_string(tox_printable_id, public_key); fprintf(stderr, "Accepted friend request from %s as %d\n", tox_printable_id, friendnumber); /* TODO: this is not freed right now, we're leaking 4 bytes per contact (OMG!) */ friendnumber_ptr = malloc(sizeof(int32_t)); if(!friendnumber_ptr) { fprintf(stderr, "Could not allocate memory for friendnumber_ptr\n"); return; } *friendnumber_ptr = friendnumber; tox_lossless_packet_registerhandler(tox, friendnumber, (PROTOCOL_MAGIC_V1)>>8, parse_lossless_packet, (void*)friendnumber_ptr); } void cleanup(int status, void *tmp) { fprintf(stderr, "kthxbye\n"); fflush(stdout); tox_kill(tox); if(client_socket) { close(client_socket); } } int do_server_loop() { struct timeval tv; fd_set fds; unsigned char tox_packet_buf[PROTOCOL_MAX_PACKET_SIZE]; tunnel *tun = NULL; tunnel *tmp = NULL; int connected = 0; tv.tv_sec = 0; tv.tv_usec = 20000; FD_ZERO(&master_server_fds); while(1) { int tmp_isconnected = 0; /* Let tox do its stuff */ tox_do(tox); /* Check change in connection state */ tmp_isconnected = tox_isconnected(tox); if(tmp_isconnected != connected) { connected = tmp_isconnected; if(connected) { fprintf(stderr, "Connected to Tox network\n"); } else { fprintf(stderr, "Disconnected from Tox network\n"); } } fds = master_server_fds; /* Poll for data from our client connection */ select(select_nfds, &fds, NULL, NULL, &tv); HASH_ITER(hh, by_id, tun, tmp) { if(FD_ISSET(tun->sockfd, &fds)) { int nbytes = recv(tun->sockfd, tox_packet_buf+PROTOCOL_BUFFER_OFFSET, READ_BUFFER_SIZE, 0); /* Check if connection closed */ if(nbytes == 0) { char data[PROTOCOL_BUFFER_OFFSET]; protocol_frame frame_st, *frame; fprintf(stderr, "conn closed!\n"); frame = &frame_st; memset(frame, 0, sizeof(protocol_frame)); frame->friendnumber = tun->friendnumber; frame->packet_type = PACKET_TYPE_TCP_FIN; frame->connid = tun->connid; frame->data_length = 0; send_frame(frame, data); tunnel_delete(tun); continue; } else { protocol_frame frame_st, *frame; frame = &frame_st; memset(frame, 0, sizeof(protocol_frame)); frame->friendnumber = tun->friendnumber; frame->packet_type = PACKET_TYPE_TCP; frame->connid = tun->connid; frame->data_length = nbytes; send_frame(frame, tox_packet_buf); } } } } } void help() { fprintf(stderr, "tuntox - Forward ports over the Tox protocol\n"); fprintf(stderr, "USAGE:\n\n"); fprintf(stderr, "-i - remote point Tox ID\n"); fprintf(stderr, "-L :: - forward : to 127.0.0.1:\n"); fprintf(stderr, "-P : - forward : to stdin/stdout (SSH ProxyCommand mode)\n"); fprintf(stderr, "-p - ping the server from -i and exit\n"); fprintf(stderr, "-C - save private key in instead of /etc/tuntox in server mode\n"); } int main(int argc, char *argv[]) { unsigned char tox_id[TOX_FRIEND_ADDRESS_SIZE]; unsigned char tox_printable_id[TOX_FRIEND_ADDRESS_SIZE * 2 + 1]; int oc; while ((oc = getopt(argc, argv, "L:pi:C:P:")) != -1) { switch(oc) { case 'L': /* Local port forwarding */ client_mode = 1; client_local_port_mode = 1; if(parse_local_port_forward(optarg, &local_port, &remote_host, &remote_port) < 0) { fprintf(stderr, "Invalid value for -L option - use something like -L 22:127.0.0.1:22\n"); exit(1); } fprintf(stderr, "Forwarding remote port %d to local port %d\n", remote_port, local_port); break; case 'P': /* Pipe forwarding */ client_mode = 1; client_pipe_mode = 1; if(parse_pipe_port_forward(optarg, &remote_host, &remote_port) < 0) { fprintf(stderr, "Invalid value for -P option - use something like -P 127.0.0.1:22\n"); exit(1); } fprintf(stderr, "Forwarding remote port %d to stdin/out\n", remote_port); break; case 'p': /* Ping */ client_mode = 1; ping_mode = 1; break; case 'i': /* Tox ID */ remote_tox_id = optarg; break; case 'C': /* Config directory */ strncpy(config_path, optarg, sizeof(config_path) - 1); if(optarg[strlen(optarg) - 1] != '/') { int optarg_len = strlen(optarg); config_path[optarg_len] = '/'; config_path[optarg_len + 1] = '\0'; } break; case '?': default: help(); exit(1); } } on_exit(cleanup, NULL); /* Bootstrap tox */ tox_options.ipv6enabled = TOX_ENABLE_IPV6_DEFAULT; tox_options.udp_disabled = 0; tox_options.proxy_enabled = 0; tox = tox_new(&tox_options); if(tox == NULL) { fprintf(stderr, "tox_new() failed - trying without proxy\n"); if(!tox_options.proxy_enabled || (tox_options.proxy_enabled = 0, (tox = tox_new(&tox_options)) == NULL)) { fprintf(stderr, "tox_new() failed - trying without IPv6\n"); if(!tox_options.ipv6enabled || (tox_options.ipv6enabled = 0, (tox = tox_new(&tox_options)) == NULL)) { fprintf(stderr, "tox_new() failed - exiting\n"); exit(1); } } } set_tox_username(tox); do_bootstrap(tox); /* TODO use proper argparse */ if(client_mode) { tox_get_address(tox, tox_id); id_to_string(tox_printable_id, tox_id); tox_printable_id[TOX_FRIEND_ADDRESS_SIZE * 2] = '\0'; fprintf(stderr, "Generated Tox ID: %s\n", tox_printable_id); if(!remote_tox_id) { fprintf(stderr, "Tox id is required in client mode. Use -i 58435984ABCDEF475...\n"); exit(1); } do_client_loop(remote_tox_id); } else { /* Connect to the forwarded service */ // client_socket = get_client_socket(); if(!load_save(tox)) { /* Write generated ID if one is not already present */ write_save(tox); } tox_get_address(tox, tox_id); memset(tox_printable_id, '\0', sizeof(tox_printable_id)); id_to_string(tox_printable_id, tox_id); tox_printable_id[TOX_FRIEND_ADDRESS_SIZE * 2] = '\0'; fprintf(stderr, "Using Tox ID: %s\n", tox_printable_id); tox_callback_friend_request(tox, accept_friend_request, NULL); do_server_loop(); } return 0; }