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 const char *device_info = "OS X utun device";
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 logger(LOG_INFO, "%s is a %s", device, device_info);
126 static bool setup_device(void) {
127 // Find out which device file to open
129 if(!get_config_string(lookup_config(config_tree, "Device"), &device)) {
130 if(routing_mode == RMODE_ROUTER) {
131 device = xstrdup(DEFAULT_TUN_DEVICE);
133 device = xstrdup(DEFAULT_TAP_DEVICE);
137 // Find out if it's supposed to be a tun or a tap device
141 if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
142 if(!strcasecmp(type, "tun"))
146 else if(!strcasecmp(type, "tunemu")) {
147 device_type = DEVICE_TYPE_TUNEMU;
151 #ifdef HAVE_NET_IF_UTUN_H
152 else if(!strcasecmp(type, "utun")) {
153 device_type = DEVICE_TYPE_UTUN;
157 else if(!strcasecmp(type, "tunnohead")) {
158 device_type = DEVICE_TYPE_TUN;
159 } else if(!strcasecmp(type, "tunifhead")) {
160 device_type = DEVICE_TYPE_TUNIFHEAD;
161 } else if(!strcasecmp(type, "tap")) {
162 device_type = DEVICE_TYPE_TAP;
164 logger(LOG_ERR, "Unknown device type %s!", type);
168 #ifdef HAVE_NET_IF_UTUN_H
170 if(strncmp(device, "utun", 4) == 0 || strncmp(device, "/dev/utun", 9) == 0) {
171 device_type = DEVICE_TYPE_UTUN;
174 if(strstr(device, "tap") || routing_mode != RMODE_ROUTER) {
175 device_type = DEVICE_TYPE_TAP;
179 if(routing_mode == RMODE_SWITCH && device_type != DEVICE_TYPE_TAP) {
180 logger(LOG_ERR, "Only tap devices support switch mode!");
186 switch(device_type) {
189 case DEVICE_TYPE_TUNEMU: {
190 char dynamic_name[256] = "";
191 device_fd = tunemu_open(dynamic_name);
195 #ifdef HAVE_NET_IF_UTUN_H
197 case DEVICE_TYPE_UTUN:
202 device_fd = open(device, O_RDWR | O_NONBLOCK);
206 logger(LOG_ERR, "Could not open %s: %s", device, strerror(errno));
211 fcntl(device_fd, F_SETFD, FD_CLOEXEC);
214 // Guess what the corresponding interface is called
216 char *realname = NULL;
218 #if defined(HAVE_FDEVNAME)
219 realname = fdevname(device_fd);
220 #elif defined(HAVE_DEVNAME)
223 if(!fstat(device_fd, &buf)) {
224 realname = devname(buf.st_rdev, S_IFCHR);
233 if(!get_config_string(lookup_config(config_tree, "Interface"), &iface)) {
234 iface = xstrdup(strrchr(realname, '/') ? strrchr(realname, '/') + 1 : realname);
235 } else if(strcmp(iface, strrchr(realname, '/') ? strrchr(realname, '/') + 1 : realname)) {
236 logger(LOG_WARNING, "Warning: Interface does not match Device. $INTERFACE might be set incorrectly.");
239 // Configure the device as best as we can
241 switch(device_type) {
243 device_type = DEVICE_TYPE_TUN;
245 case DEVICE_TYPE_TUN:
250 if(ioctl(device_fd, TUNSIFHEAD, &zero, sizeof(zero)) == -1) {
251 logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno));
257 #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST)
259 const int mode = IFF_BROADCAST | IFF_MULTICAST;
260 ioctl(device_fd, TUNSIFMODE, &mode, sizeof(mode));
264 device_info = "Generic BSD tun device";
267 case DEVICE_TYPE_TUNIFHEAD:
272 if(ioctl(device_fd, TUNSIFHEAD, &one, sizeof(one)) == -1) {
273 logger(LOG_ERR, "System call `%s' failed: %s", "ioctl", strerror(errno));
279 #if defined(TUNSIFMODE) && defined(IFF_BROADCAST) && defined(IFF_MULTICAST)
281 const int mode = IFF_BROADCAST | IFF_MULTICAST;
282 ioctl(device_fd, TUNSIFMODE, &mode, sizeof(mode));
286 device_info = "Generic BSD tun device";
289 case DEVICE_TYPE_TAP:
290 if(routing_mode == RMODE_ROUTER) {
291 overwrite_mac = true;
294 device_info = "Generic BSD tap device";
299 if(ioctl(device_fd, TAPGIFNAME, (void *)&ifr) == 0) {
304 iface = xstrdup(ifr.ifr_name);
312 case DEVICE_TYPE_TUNEMU:
313 device_info = "BSD tunemu device";
321 ioctl(device_fd, SIOCGIFADDR, mymac.x);
326 logger(LOG_INFO, "%s is a %s", device, device_info);
331 static void close_device(void) {
332 switch(device_type) {
335 case DEVICE_TYPE_TUNEMU:
336 tunemu_close(device_fd);
348 static bool read_packet(vpn_packet_t *packet) {
351 switch(device_type) {
352 case DEVICE_TYPE_TUN:
354 case DEVICE_TYPE_TUNEMU:
355 if(device_type == DEVICE_TYPE_TUNEMU) {
356 lenin = tunemu_read(device_fd, packet->data + 14, MTU - 14);
359 lenin = read(device_fd, packet->data + 14, MTU - 14);
362 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
363 device, strerror(errno));
367 switch(packet->data[14] >> 4) {
369 packet->data[12] = 0x08;
370 packet->data[13] = 0x00;
374 packet->data[12] = 0x86;
375 packet->data[13] = 0xDD;
379 ifdebug(TRAFFIC) logger(LOG_ERR,
380 "Unknown IP version %d while reading packet from %s %s",
381 packet->data[14] >> 4, device_info, device);
385 memset(packet->data, 0, 12);
386 packet->len = lenin + 14;
389 case DEVICE_TYPE_UTUN:
390 case DEVICE_TYPE_TUNIFHEAD: {
391 if((lenin = read(device_fd, packet->data + 10, MTU - 10)) <= 0) {
392 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
393 device, strerror(errno));
397 switch(packet->data[14] >> 4) {
399 packet->data[12] = 0x08;
400 packet->data[13] = 0x00;
404 packet->data[12] = 0x86;
405 packet->data[13] = 0xDD;
409 ifdebug(TRAFFIC) logger(LOG_ERR,
410 "Unknown IP version %d while reading packet from %s %s",
411 packet->data[14] >> 4, device_info, device);
415 memset(packet->data, 0, 12);
416 packet->len = lenin + 10;
420 case DEVICE_TYPE_TAP:
421 if((lenin = read(device_fd, packet->data, MTU)) <= 0) {
422 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
423 device, strerror(errno));
434 device_total_in += packet->len;
436 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Read packet of %d bytes from %s",
437 packet->len, device_info);
442 static bool write_packet(vpn_packet_t *packet) {
443 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Writing packet of %d bytes to %s",
444 packet->len, device_info);
446 switch(device_type) {
447 case DEVICE_TYPE_TUN:
448 if(write(device_fd, packet->data + 14, packet->len - 14) < 0) {
449 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
450 device, strerror(errno));
456 case DEVICE_TYPE_UTUN:
457 case DEVICE_TYPE_TUNIFHEAD: {
458 int af = (packet->data[12] << 8) + packet->data[13];
463 type = htonl(AF_INET);
467 type = htonl(AF_INET6);
471 ifdebug(TRAFFIC) logger(LOG_ERR,
472 "Unknown address family %x while writing packet to %s %s",
473 af, device_info, device);
477 memcpy(packet->data + 10, &type, sizeof(type));
479 if(write(device_fd, packet->data + 10, packet->len - 10) < 0) {
480 logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
488 case DEVICE_TYPE_TAP:
489 if(write(device_fd, packet->data, packet->len) < 0) {
490 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
491 device, strerror(errno));
499 case DEVICE_TYPE_TUNEMU:
500 if(tunemu_write(device_fd, packet->data + 14, packet->len - 14) < 0) {
501 logger(LOG_ERR, "Error while writing to %s %s: %s", device_info,
502 device, strerror(errno));
513 device_total_out += packet->len;
518 static void dump_device_stats(void) {
519 logger(LOG_DEBUG, "Statistics for %s %s:", device_info, device);
520 logger(LOG_DEBUG, " total bytes in: %10"PRIu64, device_total_in);
521 logger(LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
524 const devops_t os_devops = {
525 .setup = setup_device,
526 .close = close_device,
528 .write = write_packet,
529 .dump_stats = dump_device_stats,