iplink.c revision d5b7420a269e6e220e00cfbd69546d157fac1332 
1/*
2 * iplink.c		"ip link".
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:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 */
12
13#include <stdio.h>
14#include <stdlib.h>
15#include <unistd.h>
16#include <syslog.h>
17#include <fcntl.h>
18#include <dlfcn.h>
19#include <errno.h>
20#include <sys/socket.h>
21#include <linux/if.h>
22#include <linux/if_packet.h>
23#include <linux/if_ether.h>
24#include <linux/sockios.h>
25#include <netinet/in.h>
26#include <arpa/inet.h>
27#include <string.h>
28#include <sys/ioctl.h>
29#include <linux/sockios.h>
30
31#include "rt_names.h"
32#include "utils.h"
33#include "ip_common.h"
34
35#define IPLINK_IOCTL_COMPAT	1
36#ifndef LIBDIR
37#define LIBDIR "/usr/lib/"
38#endif
39
40static void usage(void) __attribute__((noreturn));
41static int iplink_have_newlink(void);
42
43void iplink_usage(void)
44{
45	if (iplink_have_newlink()) {
46		fprintf(stderr, "Usage: ip link add link DEV [ name ] NAME\n");
47		fprintf(stderr, "                   [ txqueuelen PACKETS ]\n");
48		fprintf(stderr, "                   [ address LLADDR ]\n");
49		fprintf(stderr, "                   [ broadcast LLADDR ]\n");
50		fprintf(stderr, "                   [ mtu MTU ]\n");
51		fprintf(stderr, "                   type TYPE [ ARGS ]\n");
52		fprintf(stderr, "       ip link delete DEV type TYPE [ ARGS ]\n");
53		fprintf(stderr, "\n");
54		fprintf(stderr, "       ip link set { dev DEVICE | group DEVGROUP } [ { up | down } ]\n");
55	} else
56		fprintf(stderr, "Usage: ip link set DEVICE [ { up | down } ]\n");
57
58	fprintf(stderr, "	                  [ arp { on | off } ]\n");
59	fprintf(stderr, "	                  [ dynamic { on | off } ]\n");
60	fprintf(stderr, "	                  [ multicast { on | off } ]\n");
61	fprintf(stderr, "	                  [ allmulticast { on | off } ]\n");
62	fprintf(stderr, "	                  [ promisc { on | off } ]\n");
63	fprintf(stderr, "	                  [ trailers { on | off } ]\n");
64	fprintf(stderr, "	                  [ txqueuelen PACKETS ]\n");
65	fprintf(stderr, "	                  [ name NEWNAME ]\n");
66	fprintf(stderr, "	                  [ address LLADDR ]\n");
67	fprintf(stderr, "	                  [ broadcast LLADDR ]\n");
68	fprintf(stderr, "	                  [ mtu MTU ]\n");
69	fprintf(stderr, "	                  [ netns PID ]\n");
70	fprintf(stderr, "			  [ alias NAME ]\n");
71	fprintf(stderr, "	                  [ vf NUM [ mac LLADDR ]\n");
72	fprintf(stderr, "				   [ vlan VLANID [ qos VLAN-QOS ] ]\n");
73	fprintf(stderr, "				   [ rate TXRATE ] ] \n");
74	fprintf(stderr, "			  [ master DEVICE ]\n");
75	fprintf(stderr, "			  [ nomaster ]\n");
76	fprintf(stderr, "       ip link show [ DEVICE | group GROUP ]\n");
77
78	if (iplink_have_newlink()) {
79		fprintf(stderr, "\n");
80		fprintf(stderr, "TYPE := { vlan | veth | vcan | dummy | ifb | macvlan | can }\n");
81	}
82	exit(-1);
83}
84
85static void usage(void)
86{
87	iplink_usage();
88}
89
90static int on_off(char *msg)
91{
92	fprintf(stderr, "Error: argument of \"%s\" must be \"on\" or \"off\"\n", msg);
93	return -1;
94}
95
96static void *BODY;		/* cached dlopen(NULL) handle */
97static struct link_util *linkutil_list;
98
99struct link_util *get_link_kind(const char *id)
100{
101	void *dlh;
102	char buf[256];
103	struct link_util *l;
104
105	for (l = linkutil_list; l; l = l->next)
106		if (strcmp(l->id, id) == 0)
107			return l;
108
109	snprintf(buf, sizeof(buf), LIBDIR "/ip/link_%s.so", id);
110	dlh = dlopen(buf, RTLD_LAZY);
111	if (dlh == NULL) {
112		/* look in current binary, only open once */
113		dlh = BODY;
114		if (dlh == NULL) {
115			dlh = BODY = dlopen(NULL, RTLD_LAZY);
116			if (dlh == NULL)
117				return NULL;
118		}
119	}
120
121	snprintf(buf, sizeof(buf), "%s_link_util", id);
122	l = dlsym(dlh, buf);
123	if (l == NULL)
124		return NULL;
125
126	l->next = linkutil_list;
127	linkutil_list = l;
128	return l;
129}
130
131#if IPLINK_IOCTL_COMPAT
132static int have_rtnl_newlink = -1;
133
134static int accept_msg(const struct sockaddr_nl *who,
135		      struct nlmsghdr *n, void *arg)
136{
137	struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(n);
138
139	if (n->nlmsg_type == NLMSG_ERROR &&
140	    (err->error == -EOPNOTSUPP || err->error == -EINVAL))
141		have_rtnl_newlink = 0;
142	else
143		have_rtnl_newlink = 1;
144	return -1;
145}
146
147static int iplink_have_newlink(void)
148{
149	struct {
150		struct nlmsghdr		n;
151		struct ifinfomsg	i;
152		char			buf[1024];
153	} req;
154
155	if (have_rtnl_newlink < 0) {
156		memset(&req, 0, sizeof(req));
157
158		req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
159		req.n.nlmsg_flags = NLM_F_REQUEST|NLM_F_ACK;
160		req.n.nlmsg_type = RTM_NEWLINK;
161		req.i.ifi_family = AF_UNSPEC;
162
163		rtnl_send(&rth, (char *)&req.n, req.n.nlmsg_len);
164		rtnl_listen(&rth, accept_msg, NULL);
165	}
166	return have_rtnl_newlink;
167}
168#else /* IPLINK_IOCTL_COMPAT */
169static int iplink_have_newlink(void)
170{
171	return 1;
172}
173#endif /* ! IPLINK_IOCTL_COMPAT */
174
175struct iplink_req {
176	struct nlmsghdr		n;
177	struct ifinfomsg	i;
178	char			buf[1024];
179};
180
181int iplink_parse_vf(int vf, int *argcp, char ***argvp,
182			   struct iplink_req *req)
183{
184	int len, argc = *argcp;
185	char **argv = *argvp;
186	struct rtattr *vfinfo;
187
188	vfinfo = addattr_nest(&req->n, sizeof(*req), IFLA_VF_INFO);
189
190	while (NEXT_ARG_OK()) {
191		NEXT_ARG();
192		if (matches(*argv, "mac") == 0) {
193			struct ifla_vf_mac ivm;
194			NEXT_ARG();
195			ivm.vf = vf;
196			len = ll_addr_a2n((char *)ivm.mac, 32, *argv);
197			if (len < 0)
198				return -1;
199			addattr_l(&req->n, sizeof(*req), IFLA_VF_MAC, &ivm, sizeof(ivm));
200		} else if (matches(*argv, "vlan") == 0) {
201			struct ifla_vf_vlan ivv;
202			NEXT_ARG();
203			if (get_unsigned(&ivv.vlan, *argv, 0)) {
204				invarg("Invalid \"vlan\" value\n", *argv);
205			}
206			ivv.vf = vf;
207			ivv.qos = 0;
208			if (NEXT_ARG_OK()) {
209				NEXT_ARG();
210				if (matches(*argv, "qos") == 0) {
211					NEXT_ARG();
212					if (get_unsigned(&ivv.qos, *argv, 0)) {
213						invarg("Invalid \"qos\" value\n", *argv);
214					}
215				} else {
216					/* rewind arg */
217					PREV_ARG();
218				}
219			}
220			addattr_l(&req->n, sizeof(*req), IFLA_VF_VLAN, &ivv, sizeof(ivv));
221		} else if (matches(*argv, "rate") == 0) {
222			struct ifla_vf_tx_rate ivt;
223			NEXT_ARG();
224			if (get_unsigned(&ivt.rate, *argv, 0)) {
225				invarg("Invalid \"rate\" value\n", *argv);
226			}
227			ivt.vf = vf;
228			addattr_l(&req->n, sizeof(*req), IFLA_VF_TX_RATE, &ivt, sizeof(ivt));
229
230		} else {
231			/* rewind arg */
232			PREV_ARG();
233			break;
234		}
235	}
236
237	if (argc == *argcp)
238		incomplete_command();
239
240	addattr_nest_end(&req->n, vfinfo);
241
242	*argcp = argc;
243	*argvp = argv;
244	return 0;
245}
246
247
248int iplink_parse(int argc, char **argv, struct iplink_req *req,
249		char **name, char **type, char **link, char **dev, int *group)
250{
251	int ret, len;
252	char abuf[32];
253	int qlen = -1;
254	int mtu = -1;
255	int netns = -1;
256	int vf = -1;
257
258	*group = -1;
259	ret = argc;
260
261	while (argc > 0) {
262		if (strcmp(*argv, "up") == 0) {
263			req->i.ifi_change |= IFF_UP;
264			req->i.ifi_flags |= IFF_UP;
265		} else if (strcmp(*argv, "down") == 0) {
266			req->i.ifi_change |= IFF_UP;
267			req->i.ifi_flags &= ~IFF_UP;
268		} else if (strcmp(*argv, "name") == 0) {
269			NEXT_ARG();
270			*name = *argv;
271		} else if (matches(*argv, "link") == 0) {
272			NEXT_ARG();
273			*link = *argv;
274		} else if (matches(*argv, "address") == 0) {
275			NEXT_ARG();
276			len = ll_addr_a2n(abuf, sizeof(abuf), *argv);
277			if (len < 0)
278				return -1;
279			addattr_l(&req->n, sizeof(*req), IFLA_ADDRESS, abuf, len);
280		} else if (matches(*argv, "broadcast") == 0 ||
281				strcmp(*argv, "brd") == 0) {
282			NEXT_ARG();
283			len = ll_addr_a2n(abuf, sizeof(abuf), *argv);
284			if (len < 0)
285				return -1;
286			addattr_l(&req->n, sizeof(*req), IFLA_BROADCAST, abuf, len);
287		} else if (matches(*argv, "txqueuelen") == 0 ||
288				strcmp(*argv, "qlen") == 0 ||
289				matches(*argv, "txqlen") == 0) {
290			NEXT_ARG();
291			if (qlen != -1)
292				duparg("txqueuelen", *argv);
293			if (get_integer(&qlen,  *argv, 0))
294				invarg("Invalid \"txqueuelen\" value\n", *argv);
295			addattr_l(&req->n, sizeof(*req), IFLA_TXQLEN, &qlen, 4);
296		} else if (strcmp(*argv, "mtu") == 0) {
297			NEXT_ARG();
298			if (mtu != -1)
299				duparg("mtu", *argv);
300			if (get_integer(&mtu, *argv, 0))
301				invarg("Invalid \"mtu\" value\n", *argv);
302			addattr_l(&req->n, sizeof(*req), IFLA_MTU, &mtu, 4);
303                } else if (strcmp(*argv, "netns") == 0) {
304                        NEXT_ARG();
305                        if (netns != -1)
306                                duparg("netns", *argv);
307                        if (get_integer(&netns, *argv, 0))
308                                invarg("Invalid \"netns\" value\n", *argv);
309                        addattr_l(&req->n, sizeof(*req), IFLA_NET_NS_PID, &netns, 4);
310		} else if (strcmp(*argv, "multicast") == 0) {
311			NEXT_ARG();
312			req->i.ifi_change |= IFF_MULTICAST;
313			if (strcmp(*argv, "on") == 0) {
314				req->i.ifi_flags |= IFF_MULTICAST;
315			} else if (strcmp(*argv, "off") == 0) {
316				req->i.ifi_flags &= ~IFF_MULTICAST;
317			} else
318				return on_off("multicast");
319		} else if (strcmp(*argv, "allmulticast") == 0) {
320			NEXT_ARG();
321			req->i.ifi_change |= IFF_ALLMULTI;
322			if (strcmp(*argv, "on") == 0) {
323				req->i.ifi_flags |= IFF_ALLMULTI;
324			} else if (strcmp(*argv, "off") == 0) {
325				req->i.ifi_flags &= ~IFF_ALLMULTI;
326			} else
327				return on_off("allmulticast");
328		} else if (strcmp(*argv, "promisc") == 0) {
329			NEXT_ARG();
330			req->i.ifi_change |= IFF_PROMISC;
331			if (strcmp(*argv, "on") == 0) {
332				req->i.ifi_flags |= IFF_PROMISC;
333			} else if (strcmp(*argv, "off") == 0) {
334				req->i.ifi_flags &= ~IFF_PROMISC;
335			} else
336				return on_off("promisc");
337		} else if (strcmp(*argv, "trailers") == 0) {
338			NEXT_ARG();
339			req->i.ifi_change |= IFF_NOTRAILERS;
340			if (strcmp(*argv, "off") == 0) {
341				req->i.ifi_flags |= IFF_NOTRAILERS;
342			} else if (strcmp(*argv, "on") == 0) {
343				req->i.ifi_flags &= ~IFF_NOTRAILERS;
344			} else
345				return on_off("trailers");
346		} else if (strcmp(*argv, "arp") == 0) {
347			NEXT_ARG();
348			req->i.ifi_change |= IFF_NOARP;
349			if (strcmp(*argv, "on") == 0) {
350				req->i.ifi_flags &= ~IFF_NOARP;
351			} else if (strcmp(*argv, "off") == 0) {
352				req->i.ifi_flags |= IFF_NOARP;
353			} else
354				return on_off("noarp");
355		} else if (strcmp(*argv, "vf") == 0) {
356			struct rtattr *vflist;
357			NEXT_ARG();
358			if (get_integer(&vf,  *argv, 0)) {
359				invarg("Invalid \"vf\" value\n", *argv);
360			}
361			vflist = addattr_nest(&req->n, sizeof(*req),
362					      IFLA_VFINFO_LIST);
363			len = iplink_parse_vf(vf, &argc, &argv, req);
364			if (len < 0)
365				return -1;
366			addattr_nest_end(&req->n, vflist);
367		} else if (matches(*argv, "master") == 0) {
368			int ifindex;
369			NEXT_ARG();
370			ifindex = ll_name_to_index(*argv);
371			if (!ifindex)
372				invarg("Device does not exist\n", *argv);
373			addattr_l(&req->n, sizeof(*req), IFLA_MASTER,
374				  &ifindex, 4);
375		} else if (matches(*argv, "nomaster") == 0) {
376			int ifindex = 0;
377			addattr_l(&req->n, sizeof(*req), IFLA_MASTER,
378				  &ifindex, 4);
379		} else if (matches(*argv, "dynamic") == 0) {
380			NEXT_ARG();
381			req->i.ifi_change |= IFF_DYNAMIC;
382			if (strcmp(*argv, "on") == 0) {
383				req->i.ifi_flags |= IFF_DYNAMIC;
384			} else if (strcmp(*argv, "off") == 0) {
385				req->i.ifi_flags &= ~IFF_DYNAMIC;
386			} else
387				return on_off("dynamic");
388		} else if (matches(*argv, "type") == 0) {
389			NEXT_ARG();
390			*type = *argv;
391			argc--; argv++;
392			break;
393		} else if (matches(*argv, "alias") == 0) {
394			NEXT_ARG();
395			addattr_l(&req->n, sizeof(*req), IFLA_IFALIAS,
396				  *argv, strlen(*argv));
397			argc--; argv++;
398			break;
399		} else if (strcmp(*argv, "group") == 0) {
400			NEXT_ARG();
401			if (*group != -1)
402				duparg("group", *argv);
403			if (rtnl_group_a2n(group, *argv))
404				invarg("Invalid \"group\" value\n", *argv);
405		} else {
406			if (strcmp(*argv, "dev") == 0) {
407				NEXT_ARG();
408			}
409			if (matches(*argv, "help") == 0)
410				usage();
411			if (*dev)
412				duparg2("dev", *argv);
413			*dev = *argv;
414		}
415		argc--; argv++;
416	}
417
418	return ret - argc;
419}
420
421static int iplink_modify(int cmd, unsigned int flags, int argc, char **argv)
422{
423	int len;
424	char *dev = NULL;
425	char *name = NULL;
426	char *link = NULL;
427	char *type = NULL;
428	int group;
429	struct link_util *lu = NULL;
430	struct iplink_req req;
431	int ret;
432
433	memset(&req, 0, sizeof(req));
434
435	req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
436	req.n.nlmsg_flags = NLM_F_REQUEST|flags;
437	req.n.nlmsg_type = cmd;
438	req.i.ifi_family = preferred_family;
439
440	ret = iplink_parse(argc, argv, &req, &name, &type, &link, &dev, &group);
441	if (ret < 0)
442		return ret;
443
444	argc -= ret;
445	argv += ret;
446
447	if (group != -1) {
448		if (dev)
449			addattr_l(&req.n, sizeof(req), IFLA_GROUP,
450					&group, sizeof(group));
451		else {
452			if (argc) {
453				fprintf(stderr, "Garbage instead of arguments "
454						"\"%s ...\". Try \"ip link "
455						"help\".\n", *argv);
456				return -1;
457			}
458			if (flags & NLM_F_CREATE) {
459				fprintf(stderr, "group cannot be used when "
460						"creating devices.\n");
461				return -1;
462			}
463
464			req.i.ifi_index = 0;
465			addattr32(&req.n, sizeof(req), IFLA_GROUP, group);
466			if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
467				exit(2);
468			return 0;
469		}
470	}
471
472	ll_init_map(&rth);
473
474	if (type) {
475		struct rtattr *linkinfo = NLMSG_TAIL(&req.n);
476		addattr_l(&req.n, sizeof(req), IFLA_LINKINFO, NULL, 0);
477		addattr_l(&req.n, sizeof(req), IFLA_INFO_KIND, type,
478			 strlen(type));
479
480		lu = get_link_kind(type);
481		if (lu && argc) {
482			struct rtattr * data = NLMSG_TAIL(&req.n);
483			addattr_l(&req.n, sizeof(req), IFLA_INFO_DATA, NULL, 0);
484
485			if (lu->parse_opt &&
486			    lu->parse_opt(lu, argc, argv, &req.n))
487				return -1;
488
489			data->rta_len = (void *)NLMSG_TAIL(&req.n) - (void *)data;
490		} else if (argc) {
491			if (matches(*argv, "help") == 0)
492				usage();
493			fprintf(stderr, "Garbage instead of arguments \"%s ...\". "
494					"Try \"ip link help\".\n", *argv);
495			return -1;
496		}
497		linkinfo->rta_len = (void *)NLMSG_TAIL(&req.n) - (void *)linkinfo;
498	} else if (flags & NLM_F_CREATE) {
499		fprintf(stderr, "Not enough information: \"type\" argument "
500				"is required\n");
501		return -1;
502	}
503
504	if (!(flags & NLM_F_CREATE)) {
505		if (!dev) {
506			fprintf(stderr, "Not enough information: \"dev\" "
507					"argument is required.\n");
508			exit(-1);
509		}
510
511		req.i.ifi_index = ll_name_to_index(dev);
512		if (req.i.ifi_index == 0) {
513			fprintf(stderr, "Cannot find device \"%s\"\n", dev);
514			return -1;
515		}
516	} else {
517		/* Allow "ip link add dev" and "ip link add name" */
518		if (!name)
519			name = dev;
520
521		if (link) {
522			int ifindex;
523
524			ifindex = ll_name_to_index(link);
525			if (ifindex == 0) {
526				fprintf(stderr, "Cannot find device \"%s\"\n",
527					link);
528				return -1;
529			}
530			addattr_l(&req.n, sizeof(req), IFLA_LINK, &ifindex, 4);
531		}
532	}
533
534	if (name) {
535		len = strlen(name) + 1;
536		if (len == 1)
537			invarg("\"\" is not a valid device identifier\n", "name");
538		if (len > IFNAMSIZ)
539			invarg("\"name\" too long\n", name);
540		addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, len);
541	}
542
543	if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
544		exit(2);
545
546	return 0;
547}
548
549#if IPLINK_IOCTL_COMPAT
550static int get_ctl_fd(void)
551{
552	int s_errno;
553	int fd;
554
555	fd = socket(PF_INET, SOCK_DGRAM, 0);
556	if (fd >= 0)
557		return fd;
558	s_errno = errno;
559	fd = socket(PF_PACKET, SOCK_DGRAM, 0);
560	if (fd >= 0)
561		return fd;
562	fd = socket(PF_INET6, SOCK_DGRAM, 0);
563	if (fd >= 0)
564		return fd;
565	errno = s_errno;
566	perror("Cannot create control socket");
567	return -1;
568}
569
570static int do_chflags(const char *dev, __u32 flags, __u32 mask)
571{
572	struct ifreq ifr;
573	int fd;
574	int err;
575
576	strncpy(ifr.ifr_name, dev, IFNAMSIZ);
577	fd = get_ctl_fd();
578	if (fd < 0)
579		return -1;
580	err = ioctl(fd, SIOCGIFFLAGS, &ifr);
581	if (err) {
582		perror("SIOCGIFFLAGS");
583		close(fd);
584		return -1;
585	}
586	if ((ifr.ifr_flags^flags)&mask) {
587		ifr.ifr_flags &= ~mask;
588		ifr.ifr_flags |= mask&flags;
589		err = ioctl(fd, SIOCSIFFLAGS, &ifr);
590		if (err)
591			perror("SIOCSIFFLAGS");
592	}
593	close(fd);
594	return err;
595}
596
597static int do_changename(const char *dev, const char *newdev)
598{
599	struct ifreq ifr;
600	int fd;
601	int err;
602
603	strncpy(ifr.ifr_name, dev, IFNAMSIZ);
604	strncpy(ifr.ifr_newname, newdev, IFNAMSIZ);
605	fd = get_ctl_fd();
606	if (fd < 0)
607		return -1;
608	err = ioctl(fd, SIOCSIFNAME, &ifr);
609	if (err) {
610		perror("SIOCSIFNAME");
611		close(fd);
612		return -1;
613	}
614	close(fd);
615	return err;
616}
617
618static int set_qlen(const char *dev, int qlen)
619{
620	struct ifreq ifr;
621	int s;
622
623	s = get_ctl_fd();
624	if (s < 0)
625		return -1;
626
627	memset(&ifr, 0, sizeof(ifr));
628	strncpy(ifr.ifr_name, dev, IFNAMSIZ);
629	ifr.ifr_qlen = qlen;
630	if (ioctl(s, SIOCSIFTXQLEN, &ifr) < 0) {
631		perror("SIOCSIFXQLEN");
632		close(s);
633		return -1;
634	}
635	close(s);
636
637	return 0;
638}
639
640static int set_mtu(const char *dev, int mtu)
641{
642	struct ifreq ifr;
643	int s;
644
645	s = get_ctl_fd();
646	if (s < 0)
647		return -1;
648
649	memset(&ifr, 0, sizeof(ifr));
650	strncpy(ifr.ifr_name, dev, IFNAMSIZ);
651	ifr.ifr_mtu = mtu;
652	if (ioctl(s, SIOCSIFMTU, &ifr) < 0) {
653		perror("SIOCSIFMTU");
654		close(s);
655		return -1;
656	}
657	close(s);
658
659	return 0;
660}
661
662static int get_address(const char *dev, int *htype)
663{
664	struct ifreq ifr;
665	struct sockaddr_ll me;
666	socklen_t alen;
667	int s;
668
669	s = socket(PF_PACKET, SOCK_DGRAM, 0);
670	if (s < 0) {
671		perror("socket(PF_PACKET)");
672		return -1;
673	}
674
675	memset(&ifr, 0, sizeof(ifr));
676	strncpy(ifr.ifr_name, dev, IFNAMSIZ);
677	if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
678		perror("SIOCGIFINDEX");
679		close(s);
680		return -1;
681	}
682
683	memset(&me, 0, sizeof(me));
684	me.sll_family = AF_PACKET;
685	me.sll_ifindex = ifr.ifr_ifindex;
686	me.sll_protocol = htons(ETH_P_LOOP);
687	if (bind(s, (struct sockaddr*)&me, sizeof(me)) == -1) {
688		perror("bind");
689		close(s);
690		return -1;
691	}
692
693	alen = sizeof(me);
694	if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
695		perror("getsockname");
696		close(s);
697		return -1;
698	}
699	close(s);
700	*htype = me.sll_hatype;
701	return me.sll_halen;
702}
703
704static int parse_address(const char *dev, int hatype, int halen,
705		char *lla, struct ifreq *ifr)
706{
707	int alen;
708
709	memset(ifr, 0, sizeof(*ifr));
710	strncpy(ifr->ifr_name, dev, IFNAMSIZ);
711	ifr->ifr_hwaddr.sa_family = hatype;
712	alen = ll_addr_a2n(ifr->ifr_hwaddr.sa_data, 14, lla);
713	if (alen < 0)
714		return -1;
715	if (alen != halen) {
716		fprintf(stderr, "Wrong address (%s) length: expected %d bytes\n", lla, halen);
717		return -1;
718	}
719	return 0;
720}
721
722static int set_address(struct ifreq *ifr, int brd)
723{
724	int s;
725
726	s = get_ctl_fd();
727	if (s < 0)
728		return -1;
729	if (ioctl(s, brd?SIOCSIFHWBROADCAST:SIOCSIFHWADDR, ifr) < 0) {
730		perror(brd?"SIOCSIFHWBROADCAST":"SIOCSIFHWADDR");
731		close(s);
732		return -1;
733	}
734	close(s);
735	return 0;
736}
737
738
739static int do_set(int argc, char **argv)
740{
741	char *dev = NULL;
742	__u32 mask = 0;
743	__u32 flags = 0;
744	int qlen = -1;
745	int mtu = -1;
746	char *newaddr = NULL;
747	char *newbrd = NULL;
748	struct ifreq ifr0, ifr1;
749	char *newname = NULL;
750	int htype, halen;
751
752	while (argc > 0) {
753		if (strcmp(*argv, "up") == 0) {
754			mask |= IFF_UP;
755			flags |= IFF_UP;
756		} else if (strcmp(*argv, "down") == 0) {
757			mask |= IFF_UP;
758			flags &= ~IFF_UP;
759		} else if (strcmp(*argv, "name") == 0) {
760			NEXT_ARG();
761			newname = *argv;
762		} else if (matches(*argv, "address") == 0) {
763			NEXT_ARG();
764			newaddr = *argv;
765		} else if (matches(*argv, "broadcast") == 0 ||
766			   strcmp(*argv, "brd") == 0) {
767			NEXT_ARG();
768			newbrd = *argv;
769		} else if (matches(*argv, "txqueuelen") == 0 ||
770			   strcmp(*argv, "qlen") == 0 ||
771			   matches(*argv, "txqlen") == 0) {
772			NEXT_ARG();
773			if (qlen != -1)
774				duparg("txqueuelen", *argv);
775			if (get_integer(&qlen,  *argv, 0))
776				invarg("Invalid \"txqueuelen\" value\n", *argv);
777		} else if (strcmp(*argv, "mtu") == 0) {
778			NEXT_ARG();
779			if (mtu != -1)
780				duparg("mtu", *argv);
781			if (get_integer(&mtu, *argv, 0))
782				invarg("Invalid \"mtu\" value\n", *argv);
783		} else if (strcmp(*argv, "multicast") == 0) {
784			NEXT_ARG();
785			mask |= IFF_MULTICAST;
786			if (strcmp(*argv, "on") == 0) {
787				flags |= IFF_MULTICAST;
788			} else if (strcmp(*argv, "off") == 0) {
789				flags &= ~IFF_MULTICAST;
790			} else
791				return on_off("multicast");
792		} else if (strcmp(*argv, "allmulticast") == 0) {
793			NEXT_ARG();
794			mask |= IFF_ALLMULTI;
795			if (strcmp(*argv, "on") == 0) {
796				flags |= IFF_ALLMULTI;
797			} else if (strcmp(*argv, "off") == 0) {
798				flags &= ~IFF_ALLMULTI;
799			} else
800				return on_off("allmulticast");
801		} else if (strcmp(*argv, "promisc") == 0) {
802			NEXT_ARG();
803			mask |= IFF_PROMISC;
804			if (strcmp(*argv, "on") == 0) {
805				flags |= IFF_PROMISC;
806			} else if (strcmp(*argv, "off") == 0) {
807				flags &= ~IFF_PROMISC;
808			} else
809				return on_off("promisc");
810		} else if (strcmp(*argv, "trailers") == 0) {
811			NEXT_ARG();
812			mask |= IFF_NOTRAILERS;
813			if (strcmp(*argv, "off") == 0) {
814				flags |= IFF_NOTRAILERS;
815			} else if (strcmp(*argv, "on") == 0) {
816				flags &= ~IFF_NOTRAILERS;
817			} else
818				return on_off("trailers");
819		} else if (strcmp(*argv, "arp") == 0) {
820			NEXT_ARG();
821			mask |= IFF_NOARP;
822			if (strcmp(*argv, "on") == 0) {
823				flags &= ~IFF_NOARP;
824			} else if (strcmp(*argv, "off") == 0) {
825				flags |= IFF_NOARP;
826			} else
827				return on_off("noarp");
828		} else if (matches(*argv, "dynamic") == 0) {
829			NEXT_ARG();
830			mask |= IFF_DYNAMIC;
831			if (strcmp(*argv, "on") == 0) {
832				flags |= IFF_DYNAMIC;
833			} else if (strcmp(*argv, "off") == 0) {
834				flags &= ~IFF_DYNAMIC;
835			} else
836				return on_off("dynamic");
837		} else {
838                        if (strcmp(*argv, "dev") == 0) {
839				NEXT_ARG();
840			}
841			if (matches(*argv, "help") == 0)
842				usage();
843			if (dev)
844				duparg2("dev", *argv);
845			dev = *argv;
846		}
847		argc--; argv++;
848	}
849
850	if (!dev) {
851		fprintf(stderr, "Not enough of information: \"dev\" argument is required.\n");
852		exit(-1);
853	}
854
855	if (newaddr || newbrd) {
856		halen = get_address(dev, &htype);
857		if (halen < 0)
858			return -1;
859		if (newaddr) {
860			if (parse_address(dev, htype, halen, newaddr, &ifr0) < 0)
861				return -1;
862		}
863		if (newbrd) {
864			if (parse_address(dev, htype, halen, newbrd, &ifr1) < 0)
865				return -1;
866		}
867	}
868
869	if (newname && strcmp(dev, newname)) {
870		if (strlen(newname) == 0)
871			invarg("\"\" is not a valid device identifier\n", "name");
872		if (do_changename(dev, newname) < 0)
873			return -1;
874		dev = newname;
875	}
876	if (qlen != -1) {
877		if (set_qlen(dev, qlen) < 0)
878			return -1;
879	}
880	if (mtu != -1) {
881		if (set_mtu(dev, mtu) < 0)
882			return -1;
883	}
884	if (newaddr || newbrd) {
885		if (newbrd) {
886			if (set_address(&ifr1, 1) < 0)
887				return -1;
888		}
889		if (newaddr) {
890			if (set_address(&ifr0, 0) < 0)
891				return -1;
892		}
893	}
894	if (mask)
895		return do_chflags(dev, flags, mask);
896	return 0;
897}
898#endif /* IPLINK_IOCTL_COMPAT */
899
900int do_iplink(int argc, char **argv)
901{
902	if (argc > 0) {
903		if (iplink_have_newlink()) {
904			if (matches(*argv, "add") == 0)
905				return iplink_modify(RTM_NEWLINK,
906						     NLM_F_CREATE|NLM_F_EXCL,
907						     argc-1, argv+1);
908			if (matches(*argv, "set") == 0 ||
909			    matches(*argv, "change") == 0)
910				return iplink_modify(RTM_NEWLINK, 0,
911						     argc-1, argv+1);
912			if (matches(*argv, "replace") == 0)
913				return iplink_modify(RTM_NEWLINK,
914						     NLM_F_CREATE|NLM_F_REPLACE,
915						     argc-1, argv+1);
916			if (matches(*argv, "delete") == 0)
917				return iplink_modify(RTM_DELLINK, 0,
918						     argc-1, argv+1);
919		} else {
920#if IPLINK_IOCTL_COMPAT
921			if (matches(*argv, "set") == 0)
922				return do_set(argc-1, argv+1);
923#endif
924		}
925		if (matches(*argv, "show") == 0 ||
926		    matches(*argv, "lst") == 0 ||
927		    matches(*argv, "list") == 0)
928			return ipaddr_list_link(argc-1, argv+1);
929		if (matches(*argv, "help") == 0)
930			usage();
931	} else
932		return ipaddr_list_link(0, NULL);
933
934	fprintf(stderr, "Command \"%s\" is unknown, try \"ip link help\".\n", *argv);
935	exit(-1);
936}
937