/* device.c -- Interaction BSD tun/tap device Copyright (C) 2001-2005 Ivo Timmermans, 2001-2009 Guus Sliepen 2009 Grzegorz Dymarek This program 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 2 of the License, or (at your option) any later version. This program 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 this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #include "system.h" #include "conf.h" #include "logger.h" #include "net.h" #include "route.h" #include "utils.h" #include "xalloc.h" #ifdef HAVE_TUNEMU #include "bsd/tunemu.h" #endif #define DEFAULT_DEVICE "/dev/tun0" typedef enum device_type { DEVICE_TYPE_TUN, DEVICE_TYPE_TUNIFHEAD, DEVICE_TYPE_TAP, #ifdef HAVE_TUNEMU DEVICE_TYPE_TUNEMU, #endif } device_type_t; int device_fd = -1; char *device = NULL; char *iface = NULL; static char *device_info = NULL; static int device_total_in = 0; static int device_total_out = 0; #if defined(TUNEMU) static device_type_t device_type = DEVICE_TYPE_TUNEMU; #elif defined(HAVE_OPENBSD) || defined(HAVE_FREEBSD) static device_type_t device_type = DEVICE_TYPE_TUNIFHEAD; #else static device_type_t device_type = DEVICE_TYPE_TUN; #endif bool setup_device(void) { char *type; if(!get_config_string(lookup_config(config_tree, "Device"), &device)) device = xstrdup(DEFAULT_DEVICE); if(!get_config_string(lookup_config(config_tree, "Interface"), &iface)) iface = xstrdup(rindex(device, '/') ? rindex(device, '/') + 1 : device); if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) { if(!strcasecmp(type, "tun")) /* use default */; #ifdef HAVE_TUNEMU else if(!strcasecmp(type, "tunemu")) device_type = DEVICE_TYPE_TUNEMU; #endif else if(!strcasecmp(type, "tunnohead")) device_type = DEVICE_TYPE_TUN; else if(!strcasecmp(type, "tunifhead")) device_type = DEVICE_TYPE_TUNIFHEAD; else if(!strcasecmp(type, "tap")) device_type = DEVICE_TYPE_TAP; else { logger(LOG_ERR, "Unknown device type %s!", type); return false; } } else { if(strstr(device, "tap") || routing_mode != RMODE_ROUTER) device_type = DEVICE_TYPE_TAP; } switch(device_type) { #ifdef HAVE_TUNEMU case DEVICE_TYPE_TUNEMU: { char dynamic_name[256] = ""; device_fd = tunemu_open(dynamic_name); } break; #endif default: device_fd = open(device, O_RDWR | O_NONBLOCK); } if(device_fd < 0) { logger(LOG_ERR, "Could not open %s: %s", device, strerror(errno)); return false; } switch(device_type) { default: device_type = DEVICE_TYPE_TUN; case DEVICE_TYPE_TUN: #ifdef TUNSIFHEAD { const int zero = 0; if(ioctl(device_fd, TUNSIFHEAD, &zero, sizeof zero) == -1) { logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno)); return false; } } #endif #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST) { const int mode = IFF_BROADCAST | IFF_MULTICAST; ioctl(device_fd, TUNSIFMODE, &mode, sizeof mode); } #endif device_info = "Generic BSD tun device"; break; case DEVICE_TYPE_TUNIFHEAD: #ifdef TUNSIFHEAD { const int one = 1; if(ioctl(device_fd, TUNSIFHEAD, &one, sizeof one) == -1) { logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno)); return false; } } #endif #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST) { const int mode = IFF_BROADCAST | IFF_MULTICAST; ioctl(device_fd, TUNSIFMODE, &mode, sizeof mode); } #endif device_info = "Generic BSD tun device"; break; case DEVICE_TYPE_TAP: if(routing_mode == RMODE_ROUTER) overwrite_mac = true; device_info = "Generic BSD tap device"; break; #ifdef HAVE_TUNEMU case DEVICE_TYPE_TUNEMU: device_info = "BSD tunemu device"; break; #endif } logger(LOG_INFO, "%s is a %s", device, device_info); return true; } void close_device(void) { switch(device_type) { #ifdef HAVE_TUNEMU case DEVICE_TYPE_TUNEMU: tunemu_close(device_fd); break; #endif default: close(device_fd); } free(device); free(iface); } bool read_packet(vpn_packet_t *packet) { int lenin; switch(device_type) { case DEVICE_TYPE_TUN: #ifdef HAVE_TUNEMU case DEVICE_TYPE_TUNEMU: if(device_type == DEVICE_TYPE_TUNEMU) lenin = tunemu_read(device_fd, packet->data + 14, MTU - 14); else #else lenin = read(device_fd, packet->data + 14, MTU - 14); #endif if(lenin <= 0) { logger(LOG_ERR, "Error while reading from %s %s: %s", device_info, device, strerror(errno)); return false; } switch(packet->data[14] >> 4) { case 4: packet->data[12] = 0x08; packet->data[13] = 0x00; break; case 6: packet->data[12] = 0x86; packet->data[13] = 0xDD; break; default: ifdebug(TRAFFIC) logger(LOG_ERR, _ ("Unknown IP version %d while reading packet from %s %s"), packet->data[14] >> 4, device_info, device); return false; } packet->len = lenin + 14; break; case DEVICE_TYPE_TUNIFHEAD: { u_int32_t type; struct iovec vector[2] = {{&type, sizeof(type)}, {packet->data + 14, MTU - 14}}; if((lenin = readv(device_fd, vector, 2)) <= 0) { logger(LOG_ERR, "Error while reading from %s %s: %s", device_info, device, strerror(errno)); return false; } switch (ntohl(type)) { case AF_INET: packet->data[12] = 0x08; packet->data[13] = 0x00; break; case AF_INET6: packet->data[12] = 0x86; packet->data[13] = 0xDD; break; default: ifdebug(TRAFFIC) logger(LOG_ERR, _ ("Unknown address family %x while reading packet from %s %s"), ntohl(type), device_info, device); return false; } packet->len = lenin + 10; break; } case DEVICE_TYPE_TAP: if((lenin = read(device_fd, packet->data, MTU)) <= 0) { logger(LOG_ERR, "Error while reading from %s %s: %s", device_info, device, strerror(errno)); return false; } packet->len = lenin; break; default: return false; } device_total_in += packet->len; ifdebug(TRAFFIC) logger(LOG_DEBUG, "Read packet of %d bytes from %s", packet->len, device_info); logger(LOG_INFO, "E:fd_read"); return true; } bool write_packet(vpn_packet_t *packet) { ifdebug(TRAFFIC) logger(LOG_DEBUG, "Writing packet of %d bytes to %s", packet->len, device_info); switch(device_type) { case DEVICE_TYPE_TUN: if(write(device_fd, packet->data + 14, packet->len - 14) < 0) { logger(LOG_ERR, "Error while writing to %s %s: %s", device_info, device, strerror(errno)); return false; } break; case DEVICE_TYPE_TUNIFHEAD: { u_int32_t type; struct iovec vector[2] = {{&type, sizeof(type)}, {packet->data + 14, packet->len - 14}}; int af; af = (packet->data[12] << 8) + packet->data[13]; switch (af) { case 0x0800: type = htonl(AF_INET); break; case 0x86DD: type = htonl(AF_INET6); break; default: ifdebug(TRAFFIC) logger(LOG_ERR, "Unknown address family %x while writing packet to %s %s", af, device_info, device); return false; } if(writev(device_fd, vector, 2) < 0) { logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device, strerror(errno)); return false; } break; } case DEVICE_TYPE_TAP: if(write(device_fd, packet->data, packet->len) < 0) { logger(LOG_ERR, "Error while writing to %s %s: %s", device_info, device, strerror(errno)); return false; } break; #ifdef HAVE_TUNEMU case DEVICE_TYPE_TUNEMU: if(tunemu_write(device_fd, packet->data + 14, packet->len - 14) < 0) { logger(LOG_ERR, "Error while writing to %s %s: %s", device_info, device, strerror(errno)); return false; } break; #endif default: return false; } device_total_out += packet->len; return true; } void dump_device_stats(void) { logger(LOG_DEBUG, "Statistics for %s %s:", device_info, device); logger(LOG_DEBUG, " total bytes in: %10d", device_total_in); logger(LOG_DEBUG, " total bytes out: %10d", device_total_out); }