[mirror_iproute2.git] / ip / iptuntap.c

/*
 * iptunnel.c	       "ip tuntap"
 *
 *		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.
 *
 * Authors:	David Woodhouse <David.Woodhouse@intel.com>
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
#include <linux/if.h>
#include <linux/if_tun.h>
#include <pwd.h>
#include <grp.h>
#include <fcntl.h>
#include <dirent.h>
#include <errno.h>

#include "rt_names.h"
#include "utils.h"
#include "ip_common.h"

#define TUNDEV "/dev/net/tun"

static void usage(void) __attribute__((noreturn));

static void usage(void)
{
	fprintf(stderr, "Usage: ip tuntap { add | del | show | list | lst | help } [ dev PHYS_DEV ] \n");
	fprintf(stderr, "          [ mode { tun | tap } ] [ user USER ] [ group GROUP ]\n");
	fprintf(stderr, "          [ one_queue ] [ pi ] [ vnet_hdr ] [ multi_queue ]\n");
	fprintf(stderr, "\n");
	fprintf(stderr, "Where: USER  := { STRING | NUMBER }\n");
	fprintf(stderr, "       GROUP := { STRING | NUMBER }\n");
	exit(-1);
}

static int tap_add_ioctl(struct ifreq *ifr, uid_t uid, gid_t gid)
{
	int fd;
	int ret = -1;

#ifdef IFF_TUN_EXCL
	ifr->ifr_flags |= IFF_TUN_EXCL;
#endif

	fd = open(TUNDEV, O_RDWR);
	if (fd < 0) {
		perror("open");
		return -1;
	}
	if (ioctl(fd, TUNSETIFF, ifr)) {
		perror("ioctl(TUNSETIFF)");
		goto out;
	}
	if (uid != -1 && ioctl(fd, TUNSETOWNER, uid)) {
		perror("ioctl(TUNSETOWNER)");
		goto out;
	}
	if (gid != -1 && ioctl(fd, TUNSETGROUP, gid)) {
		perror("ioctl(TUNSETGROUP)");
		goto out;
	}
	if (ioctl(fd, TUNSETPERSIST, 1)) {
		perror("ioctl(TUNSETPERSIST)");
		goto out;
	}
	ret = 0;
 out:
	close(fd);
	return ret;
}

static int tap_del_ioctl(struct ifreq *ifr)
{
	int fd = open(TUNDEV, O_RDWR);
	int ret = -1;

	if (fd < 0) {
		perror("open");
		return -1;
	}
	if (ioctl(fd, TUNSETIFF, ifr)) {
		perror("ioctl(TUNSETIFF)");
		goto out;
	}
	if (ioctl(fd, TUNSETPERSIST, 0)) {
		perror("ioctl(TUNSETPERSIST)");
		goto out;
	}
	ret = 0;
 out:
	close(fd);
	return ret;

}
static int parse_args(int argc, char **argv, struct ifreq *ifr, uid_t *uid, gid_t *gid)
{
	int count = 0;

	memset(ifr, 0, sizeof(*ifr));

	ifr->ifr_flags |= IFF_NO_PI;

	while (argc > 0) {
		if (matches(*argv, "mode") == 0) {
			NEXT_ARG();
			if (matches(*argv, "tun") == 0) {
				if (ifr->ifr_flags & IFF_TAP) {
					fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
					exit(-1);
				}
				ifr->ifr_flags |= IFF_TUN;
			} else if (matches(*argv, "tap") == 0) {
				if (ifr->ifr_flags & IFF_TUN) {
					fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
					exit(-1);
				}
				ifr->ifr_flags |= IFF_TAP;
			} else {
				fprintf(stderr,"Unknown tunnel mode \"%s\"\n", *argv);
				exit(-1);
			}
		} else if (uid && matches(*argv, "user") == 0) {
			char *end;
			unsigned long user;

			NEXT_ARG();
			if (**argv && ((user = strtol(*argv, &end, 10)), !*end))
				*uid = user;
			else {
				struct passwd *pw = getpwnam(*argv);
				if (!pw) {
					fprintf(stderr, "invalid user \"%s\"\n", *argv);
					exit(-1);
				}
				*uid = pw->pw_uid;
			}
		} else if (gid && matches(*argv, "group") == 0) {
			char *end;
			unsigned long group;

			NEXT_ARG();

			if (**argv && ((group = strtol(*argv, &end, 10)), !*end))
				*gid = group;
			else {
				struct group *gr = getgrnam(*argv);
				if (!gr) {
					fprintf(stderr, "invalid group \"%s\"\n", *argv);
					exit(-1);
				}
				*gid = gr->gr_gid;
			}
		} else if (matches(*argv, "pi") == 0) {
			ifr->ifr_flags &= ~IFF_NO_PI;
		} else if (matches(*argv, "one_queue") == 0) {
			ifr->ifr_flags |= IFF_ONE_QUEUE;
		} else if (matches(*argv, "vnet_hdr") == 0) {
			ifr->ifr_flags |= IFF_VNET_HDR;
		} else if (matches(*argv, "multi_queue") == 0) {
			ifr->ifr_flags |= IFF_MULTI_QUEUE;
		} else if (matches(*argv, "dev") == 0) {
			NEXT_ARG();
			strncpy(ifr->ifr_name, *argv, IFNAMSIZ-1);
		} else {
			if (matches(*argv, "name") == 0) {
				NEXT_ARG();
			} else if (matches(*argv, "help") == 0)
				usage();
			if (ifr->ifr_name[0])
				duparg2("name", *argv);
			strncpy(ifr->ifr_name, *argv, IFNAMSIZ);
		}
		count++;
		argc--; argv++;
	}

	if (!(ifr->ifr_flags & TUN_TYPE_MASK)) {
		fprintf(stderr, "You failed to specify a tunnel mode\n");
		return -1;
	}

	return 0;
}


static int do_add(int argc, char **argv)
{
	struct ifreq ifr;
	uid_t uid = -1;
	gid_t gid = -1;

	if (parse_args(argc, argv, &ifr, &uid, &gid) < 0)
		return -1;

	return tap_add_ioctl(&ifr, uid, gid);
}

static int do_del(int argc, char **argv)
{
	struct ifreq ifr;

	if (parse_args(argc, argv, &ifr, NULL, NULL) < 0)
		return -1;

	return tap_del_ioctl(&ifr);
}

static int read_prop(char *dev, char *prop, long *value)
{
	char fname[IFNAMSIZ+25], buf[80], *endp;
	ssize_t len;
	int fd;
	long result;

	sprintf(fname, "/sys/class/net/%s/%s", dev, prop);
	fd = open(fname, O_RDONLY);
	if (fd < 0) {
		if (strcmp(prop, "tun_flags"))
			fprintf(stderr, "open %s: %s\n", fname,
				strerror(errno));
		return -1;
	}
	len = read(fd, buf, sizeof(buf)-1);
	close(fd);
	if (len < 0) {
		fprintf(stderr, "read %s: %s", fname, strerror(errno));
		return -1;
	}

	buf[len] = 0;
	result = strtol(buf, &endp, 0);
	if (*endp != '\n') {
		fprintf(stderr, "Failed to parse %s\n", fname);
		return -1;
	}
	*value = result;
	return 0;
}

static void print_flags(long flags)
{
	if (flags & IFF_TUN)
		printf(" tun");

	if (flags & IFF_TAP)
		printf(" tap");

	if (!(flags & IFF_NO_PI))
		printf(" pi");

	if (flags & IFF_ONE_QUEUE)
		printf(" one_queue");

	if (flags & IFF_VNET_HDR)
		printf(" vnet_hdr");

	flags &= ~(IFF_TUN|IFF_TAP|IFF_NO_PI|IFF_ONE_QUEUE|IFF_VNET_HDR);
	if (flags)
		printf(" UNKNOWN_FLAGS:%lx", flags);
}

static int do_show(int argc, char **argv)
{
	DIR *dir;
	struct dirent *d;
	long flags, owner = -1, group = -1;

	dir = opendir("/sys/class/net");
	if (!dir) {
		perror("opendir");
		return -1;
	}
	while ((d = readdir(dir))) {
		if (d->d_name[0] == '.' &&
		    (d->d_name[1] == 0 || d->d_name[1] == '.'))
			continue;

		if (read_prop(d->d_name, "tun_flags", &flags))
			continue;

		read_prop(d->d_name, "owner", &owner);
		read_prop(d->d_name, "group", &group);

		printf("%s:", d->d_name);
		print_flags(flags);
		if (owner != -1)
			printf(" user %ld", owner);
		if (group != -1)
			printf(" group %ld", group);
		printf("\n");
	}
	closedir(dir);
	return 0;
}

int do_iptuntap(int argc, char **argv)
{
	if (argc > 0) {
		if (matches(*argv, "add") == 0)
			return do_add(argc-1, argv+1);
		if (matches(*argv, "delete") == 0)
			return do_del(argc-1, argv+1);
		if (matches(*argv, "show") == 0 ||
                    matches(*argv, "lst") == 0 ||
                    matches(*argv, "list") == 0)
                        return do_show(argc-1, argv+1);
		if (matches(*argv, "help") == 0)
			usage();
	} else
		return do_show(0, NULL);

	fprintf(stderr, "Command \"%s\" is unknown, try \"ip tuntap help\".\n",
		*argv);
	exit(-1);
}
Commit	Line	Data
580fbd88 DW	1	/*
	2	* iptunnel.c "ip tuntap"
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation; either version
	7	* 2 of the License, or (at your option) any later version.
	8	*
	9	* Authors: David Woodhouse <David.Woodhouse@intel.com>
	10	*
	11	*/
	12
	13	#include <stdio.h>
	14	#include <stdlib.h>
	15	#include <string.h>
	16	#include <unistd.h>
	17	#include <sys/types.h>
	18	#include <sys/socket.h>
	19	#include <arpa/inet.h>
	20	#include <sys/ioctl.h>
	21	#include <linux/if.h>
	22	#include <linux/if_tun.h>
	23	#include <pwd.h>
	24	#include <grp.h>
	25	#include <fcntl.h>
	26	#include <dirent.h>
	27	#include <errno.h>
	28
	29	#include "rt_names.h"
	30	#include "utils.h"
	31	#include "ip_common.h"
	32
	33	#define TUNDEV "/dev/net/tun"
	34
	35	static void usage(void) __attribute__((noreturn));
	36
	37	static void usage(void)
	38	{
08ce8ae9	39	fprintf(stderr, "Usage: ip tuntap { add \| del \| show \| list \| lst \| help } [ dev PHYS_DEV ] \n");
580fbd88	40	fprintf(stderr, " [ mode { tun \| tap } ] [ user USER ] [ group GROUP ]\n");
c41e038f	41	fprintf(stderr, " [ one_queue ] [ pi ] [ vnet_hdr ] [ multi_queue ]\n");
580fbd88 DW	42	fprintf(stderr, "\n");
	43	fprintf(stderr, "Where: USER := { STRING \| NUMBER }\n");
	44	fprintf(stderr, " GROUP := { STRING \| NUMBER }\n");
	45	exit(-1);
	46	}
	47
	48	static int tap_add_ioctl(struct ifreq *ifr, uid_t uid, gid_t gid)
	49	{
1313ceb4	50	int fd;
580fbd88 DW	51	int ret = -1;
	52
	53	#ifdef IFF_TUN_EXCL
	54	ifr->ifr_flags \|= IFF_TUN_EXCL;
	55	#endif
	56
	57	fd = open(TUNDEV, O_RDWR);
	58	if (fd < 0) {
	59	perror("open");
	60	return -1;
	61	}
	62	if (ioctl(fd, TUNSETIFF, ifr)) {
	63	perror("ioctl(TUNSETIFF)");
	64	goto out;
	65	}
	66	if (uid != -1 && ioctl(fd, TUNSETOWNER, uid)) {
	67	perror("ioctl(TUNSETOWNER)");
	68	goto out;
	69	}
	70	if (gid != -1 && ioctl(fd, TUNSETGROUP, gid)) {
	71	perror("ioctl(TUNSETGROUP)");
	72	goto out;
	73	}
	74	if (ioctl(fd, TUNSETPERSIST, 1)) {
	75	perror("ioctl(TUNSETPERSIST)");
	76	goto out;
	77	}
	78	ret = 0;
	79	out:
	80	close(fd);
	81	return ret;
	82	}
	83
	84	static int tap_del_ioctl(struct ifreq *ifr)
	85	{
	86	int fd = open(TUNDEV, O_RDWR);
	87	int ret = -1;
	88
	89	if (fd < 0) {
	90	perror("open");
	91	return -1;
	92	}
	93	if (ioctl(fd, TUNSETIFF, ifr)) {
	94	perror("ioctl(TUNSETIFF)");
	95	goto out;
	96	}
	97	if (ioctl(fd, TUNSETPERSIST, 0)) {
	98	perror("ioctl(TUNSETPERSIST)");
	99	goto out;
	100	}
	101	ret = 0;
	102	out:
	103	close(fd);
	104	return ret;
	105
	106	}
	107	static int parse_args(int argc, char *argv, struct ifreq ifr, uid_t uid, gid_t gid)
	108	{
	109	int count = 0;
	110
	111	memset(ifr, 0, sizeof(*ifr));
	112
	113	ifr->ifr_flags \|= IFF_NO_PI;
	114
115	while (argc > 0) {
116	if (matches(*argv, "mode") == 0) {
117	NEXT_ARG();
118	if (matches(*argv, "tun") == 0) {
119	if (ifr->ifr_flags & IFF_TAP) {
120	fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
121	exit(-1);
122	}
123	ifr->ifr_flags \|= IFF_TUN;
124	} else if (matches(*argv, "tap") == 0) {
125	if (ifr->ifr_flags & IFF_TUN) {
126	fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
127	exit(-1);
128	}
129	ifr->ifr_flags \|= IFF_TAP;
130	} else {
14645ec2	131	fprintf(stderr,"Unknown tunnel mode \"%s\"\n", *argv);
580fbd88 DW	132	exit(-1);
	133	}
	134	} else if (uid && matches(*argv, "user") == 0) {
	135	char *end;
	136	unsigned long user;
	137
	138	NEXT_ARG();
	139	if (*argv && ((user = strtol(argv, &end, 10)), !*end))
	140	*uid = user;
	141	else {
	142	struct passwd pw = getpwnam(argv);
	143	if (!pw) {
	144	fprintf(stderr, "invalid user \"%s\"\n", *argv);
	145	exit(-1);
	146	}
	147	*uid = pw->pw_uid;
	148	}
	149	} else if (gid && matches(*argv, "group") == 0) {
	150	char *end;
	151	unsigned long group;
	152
	153	NEXT_ARG();
	154
	155	if (*argv && ((group = strtol(argv, &end, 10)), !*end))
	156	*gid = group;
	157	else {
	158	struct group gr = getgrnam(argv);
	159	if (!gr) {
	160	fprintf(stderr, "invalid group \"%s\"\n", *argv);
	161	exit(-1);
	162	}
	163	*gid = gr->gr_gid;
	164	}
	165	} else if (matches(*argv, "pi") == 0) {
	166	ifr->ifr_flags &= ~IFF_NO_PI;
	167	} else if (matches(*argv, "one_queue") == 0) {
	168	ifr->ifr_flags \|= IFF_ONE_QUEUE;
	169	} else if (matches(*argv, "vnet_hdr") == 0) {
	170	ifr->ifr_flags \|= IFF_VNET_HDR;
c41e038f SN	171	} else if (matches(*argv, "multi_queue") == 0) {
c41e038f SN	172	ifr->ifr_flags \|= IFF_MULTI_QUEUE;
580fbd88 DW	173	} else if (matches(*argv, "dev") == 0) {
	174	NEXT_ARG();
	175	strncpy(ifr->ifr_name, *argv, IFNAMSIZ-1);
	176	} else {
	177	if (matches(*argv, "name") == 0) {
	178	NEXT_ARG();
	179	} else if (matches(*argv, "help") == 0)
	180	usage();
	181	if (ifr->ifr_name[0])
	182	duparg2("name", *argv);
	183	strncpy(ifr->ifr_name, *argv, IFNAMSIZ);
	184	}
	185	count++;
	186	argc--; argv++;
	187	}
	188
f1a505ac	189	if (!(ifr->ifr_flags & TUN_TYPE_MASK)) {
	190	fprintf(stderr, "You failed to specify a tunnel mode\n");
	191	return -1;
	192	}
	193
580fbd88 DW	194	return 0;
	195	}
	196
	197
	198	static int do_add(int argc, char **argv)
	199	{
	200	struct ifreq ifr;
	201	uid_t uid = -1;
	202	gid_t gid = -1;
	203
	204	if (parse_args(argc, argv, &ifr, &uid, &gid) < 0)
	205	return -1;
	206
580fbd88 DW	207	return tap_add_ioctl(&ifr, uid, gid);
	208	}
	209
	210	static int do_del(int argc, char **argv)
	211	{
	212	struct ifreq ifr;
	213
	214	if (parse_args(argc, argv, &ifr, NULL, NULL) < 0)
	215	return -1;
	216
	217	return tap_del_ioctl(&ifr);
	218	}
	219
	220	static int read_prop(char dev, char prop, long *value)
	221	{
	222	char fname[IFNAMSIZ+25], buf[80], *endp;
	223	ssize_t len;
	224	int fd;
	225	long result;
	226
	227	sprintf(fname, "/sys/class/net/%s/%s", dev, prop);
	228	fd = open(fname, O_RDONLY);
	229	if (fd < 0) {
	230	if (strcmp(prop, "tun_flags"))
	231	fprintf(stderr, "open %s: %s\n", fname,
	232	strerror(errno));
	233	return -1;
	234	}
	235	len = read(fd, buf, sizeof(buf)-1);
	236	close(fd);
	237	if (len < 0) {
	238	fprintf(stderr, "read %s: %s", fname, strerror(errno));
	239	return -1;
	240	}
	241
	242	buf[len] = 0;
	243	result = strtol(buf, &endp, 0);
	244	if (*endp != '\n') {
	245	fprintf(stderr, "Failed to parse %s\n", fname);
	246	return -1;
	247	}
	248	*value = result;
	249	return 0;
	250	}
	251
	252	static void print_flags(long flags)
	253	{
	254	if (flags & IFF_TUN)
	255	printf(" tun");
	256
	257	if (flags & IFF_TAP)
	258	printf(" tap");
	259
	260	if (!(flags & IFF_NO_PI))
	261	printf(" pi");
	262
	263	if (flags & IFF_ONE_QUEUE)
	264	printf(" one_queue");
	265
	266	if (flags & IFF_VNET_HDR)
	267	printf(" vnet_hdr");
	268
	269	flags &= ~(IFF_TUN\|IFF_TAP\|IFF_NO_PI\|IFF_ONE_QUEUE\|IFF_VNET_HDR);
	270	if (flags)
271	printf(" UNKNOWN_FLAGS:%lx", flags);
272	}
273
274	static int do_show(int argc, char **argv)
275	{
276	DIR *dir;
277	struct dirent *d;
278	long flags, owner = -1, group = -1;
279
280	dir = opendir("/sys/class/net");
281	if (!dir) {
282	perror("opendir");
283	return -1;
284	}
285	while ((d = readdir(dir))) {
286	if (d->d_name[0] == '.' &&
287	(d->d_name[1] == 0 \|\| d->d_name[1] == '.'))
288	continue;
289
290	if (read_prop(d->d_name, "tun_flags", &flags))
291	continue;
292
293	read_prop(d->d_name, "owner", &owner);
294	read_prop(d->d_name, "group", &group);
295
296	printf("%s:", d->d_name);
297	print_flags(flags);
298	if (owner != -1)
299	printf(" user %ld", owner);
300	if (group != -1)
301	printf(" group %ld", group);
302	printf("\n");
303	}
e9a927dc	304	closedir(dir);
580fbd88 DW	305	return 0;
	306	}
	307
	308	int do_iptuntap(int argc, char **argv)
	309	{
	310	if (argc > 0) {
	311	if (matches(*argv, "add") == 0)
	312	return do_add(argc-1, argv+1);
6e30461e	313	if (matches(*argv, "delete") == 0)
580fbd88 DW	314	return do_del(argc-1, argv+1);
	315	if (matches(*argv, "show") == 0 \|\|
	316	matches(*argv, "lst") == 0 \|\|
	317	matches(*argv, "list") == 0)
	318	return do_show(argc-1, argv+1);
	319	if (matches(*argv, "help") == 0)
	320	usage();
	321	} else
	322	return do_show(0, NULL);
	323
	324	fprintf(stderr, "Command \"%s\" is unknown, try \"ip tuntap help\".\n",
	325	*argv);
	326	exit(-1);
	327	}