2 device.c -- Interaction BSD tun/tap device
3 Copyright (C) 2001-2005 Ivo Timmermans,
4 2001-2016 Guus Sliepen <guus@tinc-vpn.org>
5 2009 Grzegorz Dymarek <gregd72002@googlemail.com>
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License along
18 with this program; if not, write to the Free Software Foundation, Inc.,
19 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
22 #include "../system.h"
25 #include "../device.h"
26 #include "../logger.h"
30 #include "../xalloc.h"
36 #ifdef HAVE_NET_IF_UTUN_H
37 #include <sys/sys_domain.h>
38 #include <sys/kern_control.h>
39 #include <net/if_utun.h>
42 #define DEFAULT_TUN_DEVICE "/dev/tun0"
43 #define DEFAULT_TAP_DEVICE "/dev/tap0"
45 typedef enum device_type {
47 DEVICE_TYPE_TUNIFHEAD,
52 #ifdef HAVE_NET_IF_UTUN_H
60 static char *device_info = NULL;
61 static uint64_t device_total_in = 0;
62 static uint64_t device_total_out = 0;
63 #if defined(ENABLE_TUNEMU)
64 static device_type_t device_type = DEVICE_TYPE_TUNEMU;
65 #elif defined(HAVE_OPENBSD) || defined(HAVE_FREEBSD) || defined(HAVE_DRAGONFLY)
66 static device_type_t device_type = DEVICE_TYPE_TUNIFHEAD;
68 static device_type_t device_type = DEVICE_TYPE_TUN;
71 #ifdef HAVE_NET_IF_UTUN_H
72 static bool setup_utun(void) {
73 device_fd = socket(PF_SYSTEM, SOCK_DGRAM, SYSPROTO_CONTROL);
75 logger(LOG_ERR, "Could not open PF_SYSTEM socket: %s\n", strerror(errno));
79 struct ctl_info info = {};
80 strlcpy(info.ctl_name, UTUN_CONTROL_NAME, sizeof info.ctl_name);
82 if(ioctl(device_fd, CTLIOCGINFO, &info) == -1) {
83 logger(LOG_ERR, "ioctl(CTLIOCGINFO) failed: %s", strerror(errno));
88 char *p = strstr(device, "utun"), *e = NULL;
90 unit = strtol(p + 4, &e, 10);
95 struct sockaddr_ctl sc = {
98 .sc_family = AF_SYSTEM,
99 .ss_sysaddr = AF_SYS_CONTROL,
103 if(connect(device_fd, (struct sockaddr *)&sc, sizeof(sc)) == -1) {
104 logger(LOG_ERR, "Could not connect utun socket: %s\n", strerror(errno));
109 socklen_t len = sizeof name;
110 if(getsockopt(device_fd, SYSPROTO_CONTROL, UTUN_OPT_IFNAME, name, &len)) {
111 iface = xstrdup(device);
113 iface = xstrdup(name);
116 device_info = "OS X utun device";
118 logger(LOG_INFO, "%s is a %s", device, device_info);
124 static bool setup_device(void) {
125 // Find out which device file to open
127 if(!get_config_string(lookup_config(config_tree, "Device"), &device)) {
128 if(routing_mode == RMODE_ROUTER)
129 device = xstrdup(DEFAULT_TUN_DEVICE);
131 device = xstrdup(DEFAULT_TAP_DEVICE);
134 // Find out if it's supposed to be a tun or a tap device
138 if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
139 if(!strcasecmp(type, "tun"))
142 else if(!strcasecmp(type, "tunemu"))
143 device_type = DEVICE_TYPE_TUNEMU;
145 #ifdef HAVE_NET_IF_UTUN_H
146 else if(!strcasecmp(type, "utun"))
147 device_type = DEVICE_TYPE_UTUN;
149 else if(!strcasecmp(type, "tunnohead"))
150 device_type = DEVICE_TYPE_TUN;
151 else if(!strcasecmp(type, "tunifhead"))
152 device_type = DEVICE_TYPE_TUNIFHEAD;
153 else if(!strcasecmp(type, "tap"))
154 device_type = DEVICE_TYPE_TAP;
156 logger(LOG_ERR, "Unknown device type %s!", type);
160 #ifdef HAVE_NET_IF_UTUN_H
161 if(strncmp(device, "utun", 4) == 0 || strncmp(device, "/dev/utun", 9) == 0)
162 device_type = DEVICE_TYPE_UTUN;
165 if(strstr(device, "tap") || routing_mode != RMODE_ROUTER)
166 device_type = DEVICE_TYPE_TAP;
169 if(routing_mode == RMODE_SWITCH && device_type != DEVICE_TYPE_TAP) {
170 logger(LOG_ERR, "Only tap devices support switch mode!");
176 switch(device_type) {
178 case DEVICE_TYPE_TUNEMU: {
179 char dynamic_name[256] = "";
180 device_fd = tunemu_open(dynamic_name);
184 #ifdef HAVE_NET_IF_UTUN_H
185 case DEVICE_TYPE_UTUN:
189 device_fd = open(device, O_RDWR | O_NONBLOCK);
193 logger(LOG_ERR, "Could not open %s: %s", device, strerror(errno));
198 fcntl(device_fd, F_SETFD, FD_CLOEXEC);
201 // Guess what the corresponding interface is called
205 #if defined(HAVE_FDEVNAME)
206 realname = fdevname(device_fd) ? : device;
207 #elif defined(HAVE_DEVNAME)
209 if(!fstat(device_fd, &buf))
210 realname = devname(buf.st_rdev, S_IFCHR) ? : device;
215 if(!get_config_string(lookup_config(config_tree, "Interface"), &iface))
216 iface = xstrdup(strrchr(realname, '/') ? strrchr(realname, '/') + 1 : realname);
217 else if(strcmp(iface, strrchr(realname, '/') ? strrchr(realname, '/') + 1 : realname))
218 logger(LOG_WARNING, "Warning: Interface does not match Device. $INTERFACE might be set incorrectly.");
220 // Configure the device as best as we can
222 switch(device_type) {
224 device_type = DEVICE_TYPE_TUN;
225 case DEVICE_TYPE_TUN:
229 if(ioctl(device_fd, TUNSIFHEAD, &zero, sizeof zero) == -1) {
230 logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno));
235 #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST)
237 const int mode = IFF_BROADCAST | IFF_MULTICAST;
238 ioctl(device_fd, TUNSIFMODE, &mode, sizeof mode);
242 device_info = "Generic BSD tun device";
244 case DEVICE_TYPE_TUNIFHEAD:
248 if(ioctl(device_fd, TUNSIFHEAD, &one, sizeof one) == -1) {
249 logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno));
254 #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST)
256 const int mode = IFF_BROADCAST | IFF_MULTICAST;
257 ioctl(device_fd, TUNSIFMODE, &mode, sizeof mode);
261 device_info = "Generic BSD tun device";
263 case DEVICE_TYPE_TAP:
264 if(routing_mode == RMODE_ROUTER)
265 overwrite_mac = true;
266 device_info = "Generic BSD tap device";
270 if(ioctl(device_fd, TAPGIFNAME, (void*)&ifr) == 0) {
273 iface = xstrdup(ifr.ifr_name);
280 case DEVICE_TYPE_TUNEMU:
281 device_info = "BSD tunemu device";
288 ioctl(device_fd, SIOCGIFADDR, mymac.x);
291 logger(LOG_INFO, "%s is a %s", device, device_info);
296 static void close_device(void) {
297 switch(device_type) {
299 case DEVICE_TYPE_TUNEMU:
300 tunemu_close(device_fd);
311 static bool read_packet(vpn_packet_t *packet) {
314 switch(device_type) {
315 case DEVICE_TYPE_TUN:
317 case DEVICE_TYPE_TUNEMU:
318 if(device_type == DEVICE_TYPE_TUNEMU)
319 lenin = tunemu_read(device_fd, packet->data + 14, MTU - 14);
322 lenin = read(device_fd, packet->data + 14, MTU - 14);
325 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
326 device, strerror(errno));
330 switch(packet->data[14] >> 4) {
332 packet->data[12] = 0x08;
333 packet->data[13] = 0x00;
336 packet->data[12] = 0x86;
337 packet->data[13] = 0xDD;
340 ifdebug(TRAFFIC) logger(LOG_ERR,
341 "Unknown IP version %d while reading packet from %s %s",
342 packet->data[14] >> 4, device_info, device);
346 memset(packet->data, 0, 12);
347 packet->len = lenin + 14;
350 case DEVICE_TYPE_UTUN:
351 case DEVICE_TYPE_TUNIFHEAD: {
352 if((lenin = read(device_fd, packet->data + 10, MTU - 10)) <= 0) {
353 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
354 device, strerror(errno));
358 switch(packet->data[14] >> 4) {
360 packet->data[12] = 0x08;
361 packet->data[13] = 0x00;
364 packet->data[12] = 0x86;
365 packet->data[13] = 0xDD;
368 ifdebug(TRAFFIC) logger(LOG_ERR,
369 "Unknown IP version %d while reading packet from %s %s",
370 packet->data[14] >> 4, device_info, device);
374 memset(packet->data, 0, 12);
375 packet->len = lenin + 10;
379 case DEVICE_TYPE_TAP:
380 if((lenin = read(device_fd, packet->data, MTU)) <= 0) {
381 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
382 device, strerror(errno));
393 device_total_in += packet->len;
395 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Read packet of %d bytes from %s",
396 packet->len, device_info);
401 static bool write_packet(vpn_packet_t *packet) {
402 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Writing packet of %d bytes to %s",
403 packet->len, device_info);
405 switch(device_type) {
406 case DEVICE_TYPE_TUN:
407 if(write(device_fd, packet->data + 14, packet->len - 14) < 0) {
408 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
409 device, strerror(errno));
414 case DEVICE_TYPE_UTUN:
415 case DEVICE_TYPE_TUNIFHEAD: {
416 int af = (packet->data[12] << 8) + packet->data[13];
421 type = htonl(AF_INET);
424 type = htonl(AF_INET6);
427 ifdebug(TRAFFIC) logger(LOG_ERR,
428 "Unknown address family %x while writing packet to %s %s",
429 af, device_info, device);
433 memcpy(packet->data + 10, &type, sizeof type);
435 if(write(device_fd, packet->data + 10, packet->len - 10) < 0) {
436 logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
443 case DEVICE_TYPE_TAP:
444 if(write(device_fd, packet->data, packet->len) < 0) {
445 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
446 device, strerror(errno));
452 case DEVICE_TYPE_TUNEMU:
453 if(tunemu_write(device_fd, packet->data + 14, packet->len - 14) < 0) {
454 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
455 device, strerror(errno));
465 device_total_out += packet->len;
470 static void dump_device_stats(void) {
471 logger(LOG_DEBUG, "Statistics for %s %s:", device_info, device);
472 logger(LOG_DEBUG, " total bytes in: %10"PRIu64, device_total_in);
473 logger(LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
476 const devops_t os_devops = {
477 .setup = setup_device,
478 .close = close_device,
480 .write = write_packet,
481 .dump_stats = dump_device_stats,