xref: /openbsd-src/usr.sbin/arp/arp.c (revision 0b7734b3d77bb9b21afec6f4621cae6c805dbd45)
1 /*	$OpenBSD: arp.c,v 1.75 2016/05/28 07:00:18 natano Exp $ */
2 /*	$NetBSD: arp.c,v 1.12 1995/04/24 13:25:18 cgd Exp $ */
3 
4 /*
5  * Copyright (c) 1984, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Sun Microsystems, Inc.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 /*
37  * arp - display, set, delete arp table entries and wake up hosts.
38  */
39 
40 #include <sys/file.h>
41 #include <sys/socket.h>
42 #include <sys/sysctl.h>
43 #include <sys/ioctl.h>
44 #include <net/bpf.h>
45 #include <net/if.h>
46 #include <net/if_dl.h>
47 #include <net/if_types.h>
48 #include <net/route.h>
49 #include <netinet/in.h>
50 #include <netinet/if_ether.h>
51 #include <arpa/inet.h>
52 
53 #include <netdb.h>
54 #include <errno.h>
55 #include <err.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <paths.h>
60 #include <unistd.h>
61 #include <limits.h>
62 #include <ifaddrs.h>
63 
64 void dump(void);
65 int delete(const char *);
66 void search(in_addr_t addr, void (*action)(struct sockaddr_dl *sdl,
67 	struct sockaddr_inarp *sin, struct rt_msghdr *rtm));
68 void print_entry(struct sockaddr_dl *sdl,
69 	struct sockaddr_inarp *sin, struct rt_msghdr *rtm);
70 void nuke_entry(struct sockaddr_dl *sdl,
71 	struct sockaddr_inarp *sin, struct rt_msghdr *rtm);
72 static char *ether_str(struct sockaddr_dl *);
73 int wake(const char *ether_addr, const char *iface);
74 int file(char *);
75 int get(const char *);
76 int getinetaddr(const char *, struct in_addr *);
77 void getsocket(void);
78 int rtget(struct sockaddr_inarp **, struct sockaddr_dl **);
79 int rtmsg(int);
80 int set(int, char **);
81 void usage(void);
82 static char *sec2str(time_t);
83 
84 static pid_t pid;
85 static int replace;	/* replace entries when adding */
86 static int nflag;	/* no reverse dns lookups */
87 static int aflag;	/* do it for all entries */
88 static int s = -1;
89 static int rdomain;
90 
91 extern int h_errno;
92 
93 /* ROUNDUP() is nasty, but it is identical to what's in the kernel. */
94 #define ROUNDUP(a)					\
95 	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
96 
97 /* which function we're supposed to do */
98 #define F_GET		1
99 #define F_SET		2
100 #define F_FILESET	3
101 #define F_DELETE	4
102 #define F_WAKE		5
103 
104 int
105 main(int argc, char *argv[])
106 {
107 	int		 ch, func = 0, error = 0;
108 	const char	*errstr;
109 
110 	pid = getpid();
111 	opterr = 0;
112 	rdomain = getrtable();
113 	while ((ch = getopt(argc, argv, "andsFfV:W")) != -1) {
114 		switch (ch) {
115 		case 'a':
116 			aflag = 1;
117 			break;
118 		case 'n':
119 			nflag = 1;
120 			break;
121 		case 'd':
122 			if (func)
123 				usage();
124 			func = F_DELETE;
125 			break;
126 		case 's':
127 			if (func)
128 				usage();
129 			func = F_SET;
130 			break;
131 		case 'F':
132 			replace = 1;
133 			break;
134 		case 'f':
135 			if (func)
136 				usage();
137 			func = F_FILESET;
138 			break;
139 		case 'V':
140 			rdomain = strtonum(optarg, 0, RT_TABLEID_MAX, &errstr);
141 			if (errstr != NULL) {
142 				warn("bad rdomain: %s", errstr);
143 				usage();
144 			}
145 			break;
146 		case 'W':
147 			if (func)
148 				usage();
149 			func = F_WAKE;
150 			break;
151 		default:
152 			usage();
153 			break;
154 		}
155 	}
156 	argc -= optind;
157 	argv += optind;
158 
159 	if (!func)
160 		func = F_GET;
161 
162 	switch (func) {
163 	case F_GET:
164 		if (aflag && argc == 0)
165 			dump();
166 		else if (!aflag && argc == 1)
167 			error = get(argv[0]);
168 		else
169 			usage();
170 		break;
171 	case F_SET:
172 		if (argc < 2 || argc > 5)
173 			usage();
174 		if (replace)
175 			delete(argv[0]);
176 		error = set(argc, argv) ? 1 : 0;
177 		break;
178 	case F_DELETE:
179 		if (aflag && argc == 0)
180 			search(0, nuke_entry);
181 		else if (!aflag && argc == 1)
182 			error = delete(argv[0]);
183 		else
184 			usage();
185 		break;
186 	case F_FILESET:
187 		if (argc != 1)
188 			usage();
189 		error = file(argv[0]);
190 		break;
191 	case F_WAKE:
192 		if (aflag || nflag || replace || rdomain > 0)
193 			usage();
194 		if (argc == 1)
195 			error = wake(argv[0], NULL);
196 		else if (argc == 2)
197 			error = wake(argv[0], argv[1]);
198 		else
199 			usage();
200 		break;
201 	}
202 	return (error);
203 }
204 
205 /*
206  * Process a file to set standard arp entries
207  */
208 int
209 file(char *name)
210 {
211 	char	 line[100], arg[5][50], *args[5];
212 	int	 i, retval;
213 	FILE	*fp;
214 
215 	if ((fp = fopen(name, "r")) == NULL)
216 		err(1, "cannot open %s", name);
217 	args[0] = &arg[0][0];
218 	args[1] = &arg[1][0];
219 	args[2] = &arg[2][0];
220 	args[3] = &arg[3][0];
221 	args[4] = &arg[4][0];
222 	retval = 0;
223 	while (fgets(line, sizeof(line), fp) != NULL) {
224 		i = sscanf(line, "%49s %49s %49s %49s %49s", arg[0], arg[1],
225 		    arg[2], arg[3], arg[4]);
226 		if (i < 2) {
227 			warnx("bad line: %s", line);
228 			retval = 1;
229 			continue;
230 		}
231 		if (replace)
232 			delete(arg[0]);
233 		if (set(i, args))
234 			retval = 1;
235 	}
236 	fclose(fp);
237 	return (retval);
238 }
239 
240 void
241 getsocket(void)
242 {
243 	socklen_t len = sizeof(rdomain);
244 
245 	if (s >= 0)
246 		return;
247 	s = socket(PF_ROUTE, SOCK_RAW, 0);
248 	if (s < 0)
249 		err(1, "socket");
250 	if (setsockopt(s, PF_ROUTE, ROUTE_TABLEFILTER, &rdomain, len) < 0)
251 		err(1, "ROUTE_TABLEFILTER");
252 
253 	if (pledge("stdio dns", NULL) == -1)
254 		err(1, "pledge");
255 }
256 
257 struct sockaddr_in	so_mask = { 8, 0, 0, { 0xffffffff } };
258 struct sockaddr_inarp	blank_sin = { sizeof(blank_sin), AF_INET }, sin_m;
259 struct sockaddr_dl	blank_sdl = { sizeof(blank_sdl), AF_LINK }, sdl_m;
260 struct sockaddr_dl	ifp_m = { sizeof(&ifp_m), AF_LINK };
261 time_t			expire_time;
262 int			flags, export_only, doing_proxy, found_entry;
263 struct	{
264 	struct rt_msghdr	m_rtm;
265 	char			m_space[512];
266 }	m_rtmsg;
267 
268 /*
269  * Set an individual arp entry
270  */
271 int
272 set(int argc, char *argv[])
273 {
274 	struct sockaddr_inarp *sin;
275 	struct sockaddr_dl *sdl;
276 	struct rt_msghdr *rtm;
277 	char *eaddr = argv[1], *host = argv[0];
278 	struct ether_addr *ea;
279 
280 	sin = &sin_m;
281 	rtm = &(m_rtmsg.m_rtm);
282 
283 	getsocket();
284 	argc -= 2;
285 	argv += 2;
286 	sdl_m = blank_sdl;		/* struct copy */
287 	sin_m = blank_sin;		/* struct copy */
288 	if (getinetaddr(host, &sin->sin_addr) == -1)
289 		return (1);
290 	ea = ether_aton(eaddr);
291 	if (ea == NULL)
292 		errx(1, "invalid ethernet address: %s", eaddr);
293 	memcpy(LLADDR(&sdl_m), ea, sizeof(*ea));
294 	sdl_m.sdl_alen = 6;
295 	expire_time = 0;
296 	doing_proxy = flags = export_only = 0;
297 	while (argc-- > 0) {
298 		if (strncmp(argv[0], "temp", 4) == 0) {
299 			struct timeval now;
300 
301 			gettimeofday(&now, 0);
302 			expire_time = now.tv_sec + 20 * 60;
303 			if (flags & RTF_PERMANENT_ARP) {
304 				/* temp or permanent, not both */
305 				usage();
306 				return (0);
307 			}
308 		} else if (strncmp(argv[0], "pub", 3) == 0) {
309 			flags |= RTF_ANNOUNCE;
310 			doing_proxy = SIN_PROXY;
311 		} else if (strncmp(argv[0], "permanent", 9) == 0) {
312 			flags |= RTF_PERMANENT_ARP;
313 			if (expire_time != 0) {
314 				/* temp or permanent, not both */
315 				usage();
316 				return (0);
317 			}
318 		}
319 
320 		argv++;
321 	}
322 
323 tryagain:
324 	if (rtget(&sin, &sdl)) {
325 		warn("%s", host);
326 		return (1);
327 	}
328 
329 	if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
330 		if (sdl->sdl_family == AF_LINK &&
331 		    (rtm->rtm_flags & RTF_LLINFO) &&
332 		    !(rtm->rtm_flags & RTF_GATEWAY))
333 			switch (sdl->sdl_type) {
334 			case IFT_ETHER:
335 			case IFT_FDDI:
336 			case IFT_ISO88023:
337 			case IFT_ISO88024:
338 			case IFT_ISO88025:
339 			case IFT_CARP:
340 				goto overwrite;
341 			}
342 
343 		if (doing_proxy == 0) {
344 			printf("set: can only proxy for %s\n", host);
345 			return (1);
346 		}
347 		if (sin_m.sin_other & SIN_PROXY) {
348 			printf("set: proxy entry exists for non 802 device\n");
349 			return (1);
350 		}
351 		sin_m.sin_other = SIN_PROXY;
352 		export_only = 1;
353 		goto tryagain;
354 	}
355 
356 overwrite:
357 	if (sdl->sdl_family != AF_LINK) {
358 		printf("cannot intuit interface index and type for %s\n", host);
359 		return (1);
360 	}
361 	sdl_m.sdl_type = sdl->sdl_type;
362 	sdl_m.sdl_index = sdl->sdl_index;
363 	return (rtmsg(RTM_ADD));
364 }
365 
366 #define W_ADDR	36
367 #define W_LL	17
368 #define W_IF	6
369 
370 /*
371  * Display an individual arp entry
372  */
373 int
374 get(const char *host)
375 {
376 	struct sockaddr_inarp *sin;
377 
378 	sin = &sin_m;
379 	sin_m = blank_sin;		/* struct copy */
380 	if (getinetaddr(host, &sin->sin_addr) == -1)
381 		exit(1);
382 
383 	printf("%-*.*s %-*.*s %*.*s %-10.10s %5s\n",
384 	    W_ADDR, W_ADDR, "Host", W_LL, W_LL, "Ethernet Address",
385 	    W_IF, W_IF, "Netif", "Expire", "Flags");
386 
387 	search(sin->sin_addr.s_addr, print_entry);
388 	if (found_entry == 0) {
389 		printf("%-*.*s no entry\n", W_ADDR, W_ADDR,
390 		    inet_ntoa(sin->sin_addr));
391 		return (1);
392 	}
393 	return (0);
394 }
395 
396 /*
397  * Delete an arp entry
398  */
399 int
400 delete(const char *host)
401 {
402 	struct sockaddr_inarp *sin;
403 	struct rt_msghdr *rtm;
404 	struct sockaddr_dl *sdl;
405 
406 	sin = &sin_m;
407 	rtm = &m_rtmsg.m_rtm;
408 
409 	getsocket();
410 	sin_m = blank_sin;		/* struct copy */
411 	if (getinetaddr(host, &sin->sin_addr) == -1)
412 		return (1);
413 tryagain:
414 	if (rtget(&sin, &sdl)) {
415 		warn("%s", host);
416 		return (1);
417 	}
418 	if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
419 		if (sdl->sdl_family == AF_LINK && rtm->rtm_flags & RTF_LLINFO) {
420 			if (rtm->rtm_flags & RTF_LOCAL)
421 				return (0);
422 		    	if (!(rtm->rtm_flags & RTF_GATEWAY))
423 				switch (sdl->sdl_type) {
424 				case IFT_ETHER:
425 				case IFT_FDDI:
426 				case IFT_ISO88023:
427 				case IFT_ISO88024:
428 				case IFT_ISO88025:
429 				case IFT_CARP:
430 					goto delete;
431 				}
432 		}
433 	}
434 
435 	if (sin_m.sin_other & SIN_PROXY) {
436 		warnx("delete: can't locate %s", host);
437 		return (1);
438 	} else {
439 		sin_m.sin_other = SIN_PROXY;
440 		goto tryagain;
441 	}
442 delete:
443 	if (sdl->sdl_family != AF_LINK) {
444 		printf("cannot locate %s\n", host);
445 		return (1);
446 	}
447 	if (rtmsg(RTM_DELETE))
448 		return (1);
449 	printf("%s (%s) deleted\n", host, inet_ntoa(sin->sin_addr));
450 	return (0);
451 }
452 
453 /*
454  * Search the entire arp table, and do some action on matching entries.
455  */
456 void
457 search(in_addr_t addr, void (*action)(struct sockaddr_dl *sdl,
458     struct sockaddr_inarp *sin, struct rt_msghdr *rtm))
459 {
460 	int mib[7];
461 	size_t needed;
462 	char *lim, *buf = NULL, *next;
463 	struct rt_msghdr *rtm;
464 	struct sockaddr_inarp *sin;
465 	struct sockaddr_dl *sdl;
466 
467 	mib[0] = CTL_NET;
468 	mib[1] = PF_ROUTE;
469 	mib[2] = 0;
470 	mib[3] = AF_INET;
471 	mib[4] = NET_RT_FLAGS;
472 	mib[5] = RTF_LLINFO;
473 	mib[6] = rdomain;
474 	while (1) {
475 		if (sysctl(mib, 7, NULL, &needed, NULL, 0) == -1)
476 			err(1, "route-sysctl-estimate");
477 		if (needed == 0)
478 			return;
479 		if ((buf = realloc(buf, needed)) == NULL)
480 			err(1, "malloc");
481 		if (sysctl(mib, 7, buf, &needed, NULL, 0) == -1) {
482 			if (errno == ENOMEM)
483 				continue;
484 			err(1, "actual retrieval of routing table");
485 		}
486 		lim = buf + needed;
487 		break;
488 	}
489 	for (next = buf; next < lim; next += rtm->rtm_msglen) {
490 		rtm = (struct rt_msghdr *)next;
491 		if (rtm->rtm_version != RTM_VERSION)
492 			continue;
493 		sin = (struct sockaddr_inarp *)(next + rtm->rtm_hdrlen);
494 		sdl = (struct sockaddr_dl *)(sin + 1);
495 		if (addr) {
496 			if (addr != sin->sin_addr.s_addr)
497 				continue;
498 			found_entry = 1;
499 		}
500 		(*action)(sdl, sin, rtm);
501 	}
502 	free(buf);
503 }
504 
505 /*
506  * Dump the entire ARP table
507  */
508 void
509 dump(void)
510 {
511 	printf("%-*.*s %-*.*s %*.*s %-10.10s %5s\n",
512 	    W_ADDR, W_ADDR, "Host", W_LL, W_LL, "Ethernet Address",
513 	    W_IF, W_IF, "Netif", "Expire", "Flags");
514 
515 	search(0, print_entry);
516 }
517 
518 /*
519  * Display an arp entry
520  */
521 void
522 print_entry(struct sockaddr_dl *sdl, struct sockaddr_inarp *sin,
523     struct rt_msghdr *rtm)
524 {
525 	char ifix_buf[IFNAMSIZ], *ifname, *host;
526 	struct hostent *hp = NULL;
527 	int addrwidth, llwidth, ifwidth ;
528 	struct timeval now;
529 
530 	gettimeofday(&now, 0);
531 
532 	if (nflag == 0)
533 		hp = gethostbyaddr((caddr_t)&(sin->sin_addr),
534 		    sizeof(sin->sin_addr), AF_INET);
535 	if (hp)
536 		host = hp->h_name;
537 	else
538 		host = inet_ntoa(sin->sin_addr);
539 
540 	addrwidth = strlen(host);
541 	if (addrwidth < W_ADDR)
542 		addrwidth = W_ADDR;
543 	llwidth = strlen(ether_str(sdl));
544 	if (W_ADDR + W_LL - addrwidth > llwidth)
545 		llwidth = W_ADDR + W_LL - addrwidth;
546 	ifname = if_indextoname(sdl->sdl_index, ifix_buf);
547 	if (!ifname)
548 		ifname = "?";
549 	ifwidth = strlen(ifname);
550 	if (W_ADDR + W_LL + W_IF - addrwidth - llwidth > ifwidth)
551 		ifwidth = W_ADDR + W_LL + W_IF - addrwidth - llwidth;
552 
553 	printf("%-*.*s %-*.*s %*.*s", addrwidth, addrwidth, host,
554 	    llwidth, llwidth, ether_str(sdl), ifwidth, ifwidth, ifname);
555 
556 	if (rtm->rtm_flags & (RTF_PERMANENT_ARP|RTF_LOCAL))
557 		printf(" %-10.10s", "permanent");
558 	else if (rtm->rtm_rmx.rmx_expire == 0)
559 		printf(" %-10.10s", "static");
560 	else if (rtm->rtm_rmx.rmx_expire > now.tv_sec)
561 		printf(" %-10.10s",
562 		    sec2str(rtm->rtm_rmx.rmx_expire - now.tv_sec));
563 	else
564 		printf(" %-10.10s", "expired");
565 
566 	printf(" %s%s\n",
567 	    (rtm->rtm_flags & RTF_LOCAL) ? "l" : "",
568 	    (rtm->rtm_flags & RTF_ANNOUNCE) ? "p" : "");
569 }
570 
571 /*
572  * Nuke an arp entry
573  */
574 void
575 nuke_entry(struct sockaddr_dl *sdl, struct sockaddr_inarp *sin,
576     struct rt_msghdr *rtm)
577 {
578 	char ip[20];
579 
580 	strlcpy(ip, inet_ntoa(sin->sin_addr), sizeof(ip));
581 	delete(ip);
582 }
583 
584 static char *
585 ether_str(struct sockaddr_dl *sdl)
586 {
587 	static char hbuf[NI_MAXHOST];
588 	u_char *cp;
589 
590 	if (sdl->sdl_alen) {
591 		cp = (u_char *)LLADDR(sdl);
592 		snprintf(hbuf, sizeof(hbuf), "%02x:%02x:%02x:%02x:%02x:%02x",
593 		    cp[0], cp[1], cp[2], cp[3], cp[4], cp[5]);
594 	} else
595 		snprintf(hbuf, sizeof(hbuf), "(incomplete)");
596 
597 	return(hbuf);
598 }
599 
600 void
601 usage(void)
602 {
603 	fprintf(stderr, "usage: arp [-adn] [-V rdomain] hostname\n");
604 	fprintf(stderr, "       arp [-F] [-f file] [-V rdomain] "
605 	    "-s hostname ether_addr\n"
606 	    "           [temp | permanent] [pub]\n");
607 	fprintf(stderr, "       arp -W ether_addr [iface]\n");
608 	exit(1);
609 }
610 
611 int
612 rtmsg(int cmd)
613 {
614 	static int seq;
615 	struct rt_msghdr *rtm;
616 	char *cp;
617 	int l;
618 
619 	rtm = &m_rtmsg.m_rtm;
620 	cp = m_rtmsg.m_space;
621 	errno = 0;
622 
623 	if (cmd == RTM_DELETE)
624 		goto doit;
625 	memset(&m_rtmsg, 0, sizeof(m_rtmsg));
626 	rtm->rtm_flags = flags;
627 	rtm->rtm_version = RTM_VERSION;
628 	rtm->rtm_hdrlen = sizeof(*rtm);
629 	rtm->rtm_tableid = rdomain;
630 
631 	switch (cmd) {
632 	default:
633 		errx(1, "internal wrong cmd");
634 		/*NOTREACHED*/
635 	case RTM_ADD:
636 		rtm->rtm_addrs |= RTA_GATEWAY;
637 		rtm->rtm_rmx.rmx_expire = expire_time;
638 		rtm->rtm_inits = RTV_EXPIRE;
639 		rtm->rtm_flags |= (RTF_HOST | RTF_STATIC);
640 		sin_m.sin_other = 0;
641 		if (doing_proxy) {
642 			if (export_only)
643 				sin_m.sin_other = SIN_PROXY;
644 			else {
645 				rtm->rtm_addrs |= RTA_NETMASK;
646 				rtm->rtm_flags &= ~RTF_HOST;
647 			}
648 		}
649 		/* FALLTHROUGH */
650 	case RTM_GET:
651 		rtm->rtm_addrs |= (RTA_DST | RTA_IFP);
652 	}
653 
654 #define NEXTADDR(w, s)					\
655 	if (rtm->rtm_addrs & (w)) {			\
656 		memcpy(cp, &s, sizeof(s));		\
657 		cp += ROUNDUP(sizeof(s));		\
658 	}
659 
660 	NEXTADDR(RTA_DST, sin_m);
661 	NEXTADDR(RTA_GATEWAY, sdl_m);
662 	NEXTADDR(RTA_NETMASK, so_mask);
663 	NEXTADDR(RTA_IFP, ifp_m);
664 
665 	rtm->rtm_msglen = cp - (char *)&m_rtmsg;
666 doit:
667 	l = rtm->rtm_msglen;
668 	rtm->rtm_seq = ++seq;
669 	rtm->rtm_type = cmd;
670 	if (write(s, (char *)&m_rtmsg, l) < 0)
671 		if (errno != ESRCH || cmd != RTM_DELETE) {
672 			warn("writing to routing socket");
673 			return (-1);
674 		}
675 
676 	do {
677 		l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
678 	} while (l > 0 && (rtm->rtm_version != RTM_VERSION ||
679 	    rtm->rtm_seq != seq || rtm->rtm_pid != pid));
680 
681 	if (l < 0)
682 		warn("read from routing socket");
683 	return (0);
684 }
685 
686 int
687 rtget(struct sockaddr_inarp **sinp, struct sockaddr_dl **sdlp)
688 {
689 	struct rt_msghdr *rtm = &(m_rtmsg.m_rtm);
690 	struct sockaddr_inarp *sin = NULL;
691 	struct sockaddr_dl *sdl = NULL;
692 	struct sockaddr *sa;
693 	char *cp;
694 	unsigned int i;
695 
696 	if (rtmsg(RTM_GET) < 0)
697 		return (1);
698 
699 	if (rtm->rtm_addrs) {
700 		cp = ((char *)rtm + rtm->rtm_hdrlen);
701 		for (i = 1; i; i <<= 1) {
702 			if (i & rtm->rtm_addrs) {
703 				sa = (struct sockaddr *)cp;
704 				switch (i) {
705 				case RTA_DST:
706 					sin = (struct sockaddr_inarp *)sa;
707 					break;
708 				case RTA_IFP:
709 					sdl = (struct sockaddr_dl *)sa;
710 					break;
711 				default:
712 					break;
713 				}
714 				cp += ROUNDUP(sa->sa_len);
715 			}
716 		}
717 	}
718 
719 	if (sin == NULL || sdl == NULL)
720 		return (1);
721 
722 	*sinp = sin;
723 	*sdlp = sdl;
724 
725 	return (0);
726 }
727 
728 int
729 getinetaddr(const char *host, struct in_addr *inap)
730 {
731 	struct hostent *hp;
732 
733 	if (inet_aton(host, inap) == 1)
734 		return (0);
735 	if ((hp = gethostbyname(host)) == NULL) {
736 		warnx("%s: %s", host, hstrerror(h_errno));
737 		return (-1);
738 	}
739 	memcpy(inap, hp->h_addr, sizeof(*inap));
740 	return (0);
741 }
742 
743 static char *
744 sec2str(time_t total)
745 {
746 	static char result[256];
747 	int days, hours, mins, secs;
748 	int first = 1;
749 	char *p = result;
750 	char *ep = &result[sizeof(result)];
751 	int n;
752 
753 	days = total / 3600 / 24;
754 	hours = (total / 3600) % 24;
755 	mins = (total / 60) % 60;
756 	secs = total % 60;
757 
758 	if (days) {
759 		first = 0;
760 		n = snprintf(p, ep - p, "%dd", days);
761 		if (n < 0 || n >= ep - p)
762 			return "?";
763 		p += n;
764 	}
765 	if (!first || hours) {
766 		first = 0;
767 		n = snprintf(p, ep - p, "%dh", hours);
768 		if (n < 0 || n >= ep - p)
769 			return "?";
770 		p += n;
771 	}
772 	if (!first || mins) {
773 		first = 0;
774 		n = snprintf(p, ep - p, "%dm", mins);
775 		if (n < 0 || n >= ep - p)
776 			return "?";
777 		p += n;
778 	}
779 	snprintf(p, ep - p, "%ds", secs);
780 
781 	return(result);
782 }
783 
784 /*
785  * Copyright (c) 2011 Jasper Lievisse Adriaanse <jasper@openbsd.org>
786  * Copyright (C) 2006,2007,2008,2009 Marc Balmer <mbalmer@openbsd.org>
787  * Copyright (C) 2000 Eugene M. Kim.  All rights reserved.
788  *
789  * Redistribution and use in source and binary forms, with or without
790  * modification, are permitted provided that the following conditions
791  * are met:
792  *
793  * 1. Redistributions of source code must retain the above copyright
794  *    notice, this list of conditions and the following disclaimer.
795  * 2. Author's name may not be used endorse or promote products derived
796  *    from this software without specific prior written permission.
797  *
798  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
799  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
800  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
801  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
802  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
803  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
804  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
805  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
806  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
807  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
808  * POSSIBILITY OF SUCH DAMAGE.
809  */
810 
811 int	do_wakeup(const char *, const char *, int);
812 int	bind_if_to_bpf(const char *, int);
813 int	get_ether(const char *, struct ether_addr *);
814 int	send_frame(int, const struct ether_addr *);
815 
816 int
817 wake(const char *ether_addr, const char *iface)
818 {
819 	struct ifaddrs		*ifa, *ifap;
820 	char			*pname = NULL;
821 	int			 bpf;
822 
823 	if ((bpf = open("/dev/bpf0", O_RDWR)) == -1)
824 		err(1, "Failed to bind to bpf");
825 
826 	if (iface == NULL) {
827 		if (getifaddrs(&ifa) == -1)
828 			errx(1, "Could not get interface addresses.");
829 
830 		for (ifap = ifa; ifap != NULL; ifap = ifap->ifa_next){
831 			if (pname && !strcmp(pname, ifap->ifa_name))
832 				continue;
833 			pname = ifap->ifa_name;
834 
835 			/*
836 			 * We're only interested in sending the WoL frame on
837 			 * certain interfaces. So skip the loopback interface,
838 			 * as well as point-to-point and down interfaces.
839 			 */
840 			if ((ifap->ifa_flags & IFF_LOOPBACK) ||
841 			    (ifap->ifa_flags & IFF_POINTOPOINT) ||
842 			    (!(ifap->ifa_flags & IFF_UP)) ||
843 			    (!(ifap->ifa_flags & IFF_BROADCAST)))
844 				continue;
845 
846 			do_wakeup(ether_addr, ifap->ifa_name, bpf);
847 		}
848 		freeifaddrs(ifa);
849 	} else {
850 		do_wakeup(ether_addr, iface, bpf);
851 	}
852 
853 	(void)close(bpf);
854 
855 	return 0;
856 }
857 
858 int
859 do_wakeup(const char *eaddr, const char *iface, int bpf)
860 {
861 	struct ether_addr	 macaddr;
862 
863 	if (get_ether(eaddr, &macaddr) != 0)
864 		errx(1, "Invalid Ethernet address: %s", eaddr);
865 	if (bind_if_to_bpf(iface, bpf) != 0)
866 		errx(1, "Failed to bind %s to bpf.", iface);
867 	if (send_frame(bpf, &macaddr) != 0)
868 		errx(1, "Failed to send WoL frame on %s", iface);
869 	return 0;
870 }
871 
872 int
873 bind_if_to_bpf(const char *ifname, int bpf)
874 {
875 	struct ifreq ifr;
876 	u_int dlt;
877 
878 	if (strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name)) >=
879 	    sizeof(ifr.ifr_name))
880 		return -1;
881 	if (ioctl(bpf, BIOCSETIF, &ifr) == -1)
882 		return -1;
883 	if (ioctl(bpf, BIOCGDLT, &dlt) == -1)
884 		return -1;
885 	if (dlt != DLT_EN10MB)
886 		return -1;
887 	return 0;
888 }
889 
890 int
891 get_ether(const char *text, struct ether_addr *addr)
892 {
893 	struct ether_addr *eaddr;
894 
895 	eaddr = ether_aton(text);
896 
897 	if (eaddr == NULL) {
898 		if (ether_hostton(text, addr))
899 			return -1;
900 	} else {
901 		*addr = *eaddr;
902 		return 0;
903 	}
904 
905 	return 0;
906 }
907 
908 #define SYNC_LEN 6
909 #define DESTADDR_COUNT 16
910 
911 int
912 send_frame(int bpf, const struct ether_addr *addr)
913 {
914 	struct {
915 		struct ether_header hdr;
916 		u_char sync[SYNC_LEN];
917 		u_char dest[ETHER_ADDR_LEN * DESTADDR_COUNT];
918 	} __packed pkt;
919 	u_char *p;
920 	int i;
921 
922 	(void)memset(&pkt, 0, sizeof(pkt));
923 	(void)memset(&pkt.hdr.ether_dhost, 0xff, sizeof(pkt.hdr.ether_dhost));
924 	pkt.hdr.ether_type = htons(0);
925 	(void)memset(pkt.sync, 0xff, SYNC_LEN);
926 	for (p = pkt.dest, i = 0; i < DESTADDR_COUNT; p += ETHER_ADDR_LEN, i++)
927 		bcopy(addr->ether_addr_octet, p, ETHER_ADDR_LEN);
928 	if (write(bpf, &pkt, sizeof(pkt)) != sizeof(pkt))
929 		return (errno);
930 	return (0);
931 }
932