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,
58 static char *device_info = NULL;
59 static uint64_t device_total_in = 0;
60 static uint64_t device_total_out = 0;
61 #if defined(ENABLE_TUNEMU)
62 static device_type_t device_type = DEVICE_TYPE_TUNEMU;
63 #elif defined(HAVE_OPENBSD) || defined(HAVE_FREEBSD) || defined(HAVE_DRAGONFLY)
64 static device_type_t device_type = DEVICE_TYPE_TUNIFHEAD;
66 static device_type_t device_type = DEVICE_TYPE_TUN;
69 #ifdef HAVE_NET_IF_UTUN_H
70 static bool setup_utun(void) {
71 device_fd = socket(PF_SYSTEM, SOCK_DGRAM, SYSPROTO_CONTROL);
74 logger(LOG_ERR, "Could not open PF_SYSTEM socket: %s\n", strerror(errno));
78 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;
91 unit = strtol(p + 4, &e, 10);
98 struct sockaddr_ctl sc = {
100 .sc_len = sizeof(sc),
101 .sc_family = AF_SYSTEM,
102 .ss_sysaddr = AF_SYS_CONTROL,
106 if(connect(device_fd, (struct sockaddr *)&sc, sizeof(sc)) == -1) {
107 logger(LOG_ERR, "Could not connect utun socket: %s\n", strerror(errno));
112 socklen_t len = sizeof(name);
114 if(getsockopt(device_fd, SYSPROTO_CONTROL, UTUN_OPT_IFNAME, name, &len)) {
115 iface = xstrdup(device);
117 iface = xstrdup(name);
120 device_info = "OS X utun device";
122 logger(LOG_INFO, "%s is a %s", device, device_info);
128 static bool setup_device(void) {
129 // Find out which device file to open
131 if(!get_config_string(lookup_config(config_tree, "Device"), &device)) {
132 if(routing_mode == RMODE_ROUTER) {
133 device = xstrdup(DEFAULT_TUN_DEVICE);
135 device = xstrdup(DEFAULT_TAP_DEVICE);
139 // Find out if it's supposed to be a tun or a tap device
143 if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
144 if(!strcasecmp(type, "tun"))
148 else if(!strcasecmp(type, "tunemu")) {
149 device_type = DEVICE_TYPE_TUNEMU;
153 #ifdef HAVE_NET_IF_UTUN_H
154 else if(!strcasecmp(type, "utun")) {
155 device_type = DEVICE_TYPE_UTUN;
159 else if(!strcasecmp(type, "tunnohead")) {
160 device_type = DEVICE_TYPE_TUN;
161 } else if(!strcasecmp(type, "tunifhead")) {
162 device_type = DEVICE_TYPE_TUNIFHEAD;
163 } else if(!strcasecmp(type, "tap")) {
164 device_type = DEVICE_TYPE_TAP;
166 logger(LOG_ERR, "Unknown device type %s!", type);
170 #ifdef HAVE_NET_IF_UTUN_H
172 if(strncmp(device, "utun", 4) == 0 || strncmp(device, "/dev/utun", 9) == 0) {
173 device_type = DEVICE_TYPE_UTUN;
176 if(strstr(device, "tap") || routing_mode != RMODE_ROUTER) {
177 device_type = DEVICE_TYPE_TAP;
181 if(routing_mode == RMODE_SWITCH && device_type != DEVICE_TYPE_TAP) {
182 logger(LOG_ERR, "Only tap devices support switch mode!");
188 switch(device_type) {
191 case DEVICE_TYPE_TUNEMU: {
192 char dynamic_name[256] = "";
193 device_fd = tunemu_open(dynamic_name);
197 #ifdef HAVE_NET_IF_UTUN_H
199 case DEVICE_TYPE_UTUN:
204 device_fd = open(device, O_RDWR | O_NONBLOCK);
208 logger(LOG_ERR, "Could not open %s: %s", device, strerror(errno));
213 fcntl(device_fd, F_SETFD, FD_CLOEXEC);
216 // Guess what the corresponding interface is called
218 char *realname = NULL;
220 #if defined(HAVE_FDEVNAME)
221 realname = fdevname(device_fd);
222 #elif defined(HAVE_DEVNAME)
225 if(!fstat(device_fd, &buf)) {
226 realname = devname(buf.st_rdev, S_IFCHR);
235 if(!get_config_string(lookup_config(config_tree, "Interface"), &iface)) {
236 iface = xstrdup(strrchr(realname, '/') ? strrchr(realname, '/') + 1 : realname);
237 } else if(strcmp(iface, strrchr(realname, '/') ? strrchr(realname, '/') + 1 : realname)) {
238 logger(LOG_WARNING, "Warning: Interface does not match Device. $INTERFACE might be set incorrectly.");
241 // Configure the device as best as we can
243 switch(device_type) {
245 device_type = DEVICE_TYPE_TUN;
247 case DEVICE_TYPE_TUN:
252 if(ioctl(device_fd, TUNSIFHEAD, &zero, sizeof(zero)) == -1) {
253 logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno));
259 #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST)
261 const int mode = IFF_BROADCAST | IFF_MULTICAST;
262 ioctl(device_fd, TUNSIFMODE, &mode, sizeof(mode));
266 device_info = "Generic BSD tun device";
269 case DEVICE_TYPE_TUNIFHEAD:
274 if(ioctl(device_fd, TUNSIFHEAD, &one, sizeof(one)) == -1) {
275 logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno));
281 #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST)
283 const int mode = IFF_BROADCAST | IFF_MULTICAST;
284 ioctl(device_fd, TUNSIFMODE, &mode, sizeof(mode));
288 device_info = "Generic BSD tun device";
291 case DEVICE_TYPE_TAP:
292 if(routing_mode == RMODE_ROUTER) {
293 overwrite_mac = true;
296 device_info = "Generic BSD tap device";
301 if(ioctl(device_fd, TAPGIFNAME, (void *)&ifr) == 0) {
306 iface = xstrdup(ifr.ifr_name);
314 case DEVICE_TYPE_TUNEMU:
315 device_info = "BSD tunemu device";
323 ioctl(device_fd, SIOCGIFADDR, mymac.x);
328 logger(LOG_INFO, "%s is a %s", device, device_info);
333 static void close_device(void) {
334 switch(device_type) {
337 case DEVICE_TYPE_TUNEMU:
338 tunemu_close(device_fd);
350 static bool read_packet(vpn_packet_t *packet) {
353 switch(device_type) {
354 case DEVICE_TYPE_TUN:
356 case DEVICE_TYPE_TUNEMU:
357 if(device_type == DEVICE_TYPE_TUNEMU) {
358 lenin = tunemu_read(device_fd, packet->data + 14, MTU - 14);
361 lenin = read(device_fd, packet->data + 14, MTU - 14);
364 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
365 device, strerror(errno));
369 switch(packet->data[14] >> 4) {
371 packet->data[12] = 0x08;
372 packet->data[13] = 0x00;
376 packet->data[12] = 0x86;
377 packet->data[13] = 0xDD;
381 ifdebug(TRAFFIC) logger(LOG_ERR,
382 "Unknown IP version %d while reading packet from %s %s",
383 packet->data[14] >> 4, device_info, device);
387 memset(packet->data, 0, 12);
388 packet->len = lenin + 14;
391 case DEVICE_TYPE_UTUN:
392 case DEVICE_TYPE_TUNIFHEAD: {
393 if((lenin = read(device_fd, packet->data + 10, MTU - 10)) <= 0) {
394 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
395 device, strerror(errno));
399 switch(packet->data[14] >> 4) {
401 packet->data[12] = 0x08;
402 packet->data[13] = 0x00;
406 packet->data[12] = 0x86;
407 packet->data[13] = 0xDD;
411 ifdebug(TRAFFIC) logger(LOG_ERR,
412 "Unknown IP version %d while reading packet from %s %s",
413 packet->data[14] >> 4, device_info, device);
417 memset(packet->data, 0, 12);
418 packet->len = lenin + 10;
422 case DEVICE_TYPE_TAP:
423 if((lenin = read(device_fd, packet->data, MTU)) <= 0) {
424 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
425 device, strerror(errno));
436 device_total_in += packet->len;
438 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Read packet of %d bytes from %s",
439 packet->len, device_info);
444 static bool write_packet(vpn_packet_t *packet) {
445 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Writing packet of %d bytes to %s",
446 packet->len, device_info);
448 switch(device_type) {
449 case DEVICE_TYPE_TUN:
450 if(write(device_fd, packet->data + 14, packet->len - 14) < 0) {
451 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
452 device, strerror(errno));
458 case DEVICE_TYPE_UTUN:
459 case DEVICE_TYPE_TUNIFHEAD: {
460 int af = (packet->data[12] << 8) + packet->data[13];
465 type = htonl(AF_INET);
469 type = htonl(AF_INET6);
473 ifdebug(TRAFFIC) logger(LOG_ERR,
474 "Unknown address family %x while writing packet to %s %s",
475 af, device_info, device);
479 memcpy(packet->data + 10, &type, sizeof(type));
481 if(write(device_fd, packet->data + 10, packet->len - 10) < 0) {
482 logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
490 case DEVICE_TYPE_TAP:
491 if(write(device_fd, packet->data, packet->len) < 0) {
492 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
493 device, strerror(errno));
501 case DEVICE_TYPE_TUNEMU:
502 if(tunemu_write(device_fd, packet->data + 14, packet->len - 14) < 0) {
503 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
504 device, strerror(errno));
515 device_total_out += packet->len;
520 static void dump_device_stats(void) {
521 logger(LOG_DEBUG, "Statistics for %s %s:", device_info, device);
522 logger(LOG_DEBUG, " total bytes in: %10"PRIu64, device_total_in);
523 logger(LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
526 const devops_t os_devops = {
527 .setup = setup_device,
528 .close = close_device,
530 .write = write_packet,
531 .dump_stats = dump_device_stats,