xref: /freebsd/usr.sbin/rtsold/rtsold.c (revision 3fc36ee018bb836bd1796067cf4ef8683f166ebc)
1 /*	$KAME: rtsold.c,v 1.67 2003/05/17 18:16:15 itojun Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 #include <sys/types.h>
35 #include <sys/ioctl.h>
36 #include <sys/socket.h>
37 #include <sys/param.h>
38 
39 #include <net/if.h>
40 #include <net/if_dl.h>
41 
42 #include <netinet/in.h>
43 #include <netinet/icmp6.h>
44 #include <netinet/in_var.h>
45 #include <arpa/inet.h>
46 
47 #include <netinet6/nd6.h>
48 
49 #include <signal.h>
50 #include <unistd.h>
51 #include <syslog.h>
52 #include <string.h>
53 #include <stdlib.h>
54 #include <stdio.h>
55 #include <time.h>
56 #include <errno.h>
57 #include <err.h>
58 #include <stdarg.h>
59 #include <ifaddrs.h>
60 #include <poll.h>
61 
62 #include "rtsold.h"
63 
64 #define RTSOL_DUMPFILE	"/var/run/rtsold.dump";
65 #define RTSOL_PIDFILE	"/var/run/rtsold.pid";
66 
67 struct timespec tm_max;
68 static int log_upto = 999;
69 static int fflag = 0;
70 
71 int Fflag = 0;	/* force setting sysctl parameters */
72 int aflag = 0;
73 int dflag = 0;
74 int uflag = 0;
75 
76 const char *otherconf_script;
77 const char *resolvconf_script = "/sbin/resolvconf";
78 
79 /* protocol constants */
80 #define MAX_RTR_SOLICITATION_DELAY	1 /* second */
81 #define RTR_SOLICITATION_INTERVAL	4 /* seconds */
82 #define MAX_RTR_SOLICITATIONS		3 /* times */
83 
84 /*
85  * implementation dependent constants in seconds
86  * XXX: should be configurable
87  */
88 #define PROBE_INTERVAL 60
89 
90 /* static variables and functions */
91 static int mobile_node = 0;
92 static const char *pidfilename = RTSOL_PIDFILE;
93 
94 #ifndef SMALL
95 static int do_dump;
96 static const char *dumpfilename = RTSOL_DUMPFILE;
97 #endif
98 
99 #if 0
100 static int ifreconfig(char *);
101 #endif
102 
103 static int make_packet(struct ifinfo *);
104 static struct timespec *rtsol_check_timer(void);
105 
106 #ifndef SMALL
107 static void rtsold_set_dump_file(int);
108 #endif
109 static void usage(void);
110 
111 int
112 main(int argc, char **argv)
113 {
114 	int s, ch, once = 0;
115 	struct timespec *timeout;
116 	const char *opts;
117 	struct pollfd set[2];
118 	int rtsock;
119 	char *argv0;
120 
121 #ifndef SMALL
122 	/* rtsold */
123 	opts = "adDfFm1O:p:R:u";
124 #else
125 	/* rtsol */
126 	opts = "adDFO:R:u";
127 	fflag = 1;
128 	once = 1;
129 #endif
130 	argv0 = argv[0];
131 
132 	while ((ch = getopt(argc, argv, opts)) != -1) {
133 		switch (ch) {
134 		case 'a':
135 			aflag = 1;
136 			break;
137 		case 'd':
138 			dflag += 1;
139 			break;
140 		case 'D':
141 			dflag += 2;
142 			break;
143 		case 'f':
144 			fflag = 1;
145 			break;
146 		case 'F':
147 			Fflag = 1;
148 			break;
149 		case 'm':
150 			mobile_node = 1;
151 			break;
152 		case '1':
153 			once = 1;
154 			break;
155 		case 'O':
156 			otherconf_script = optarg;
157 			break;
158 		case 'p':
159 			pidfilename = optarg;
160 			break;
161 		case 'R':
162 			resolvconf_script = optarg;
163 			break;
164 		case 'u':
165 			uflag = 1;
166 			break;
167 		default:
168 			usage();
169 			exit(1);
170 		}
171 	}
172 	argc -= optind;
173 	argv += optind;
174 
175 	if ((!aflag && argc == 0) || (aflag && argc != 0)) {
176 		usage();
177 		exit(1);
178 	}
179 
180 	/* Generate maximum time in timespec. */
181 	tm_max.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
182 	tm_max.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
183 
184 	/* set log level */
185 	if (dflag > 1)
186 		log_upto = LOG_DEBUG;
187 	else if (dflag > 0)
188 		log_upto = LOG_INFO;
189 	else
190 		log_upto = LOG_NOTICE;
191 
192 	if (!fflag) {
193 		char *ident;
194 
195 		ident = strrchr(argv0, '/');
196 		if (!ident)
197 			ident = argv0;
198 		else
199 			ident++;
200 		openlog(ident, LOG_NDELAY|LOG_PID, LOG_DAEMON);
201 		if (log_upto >= 0)
202 			setlogmask(LOG_UPTO(log_upto));
203 	}
204 
205 	if (otherconf_script && *otherconf_script != '/') {
206 		errx(1, "configuration script (%s) must be an absolute path",
207 		    otherconf_script);
208 	}
209 	if (resolvconf_script && *resolvconf_script != '/') {
210 		errx(1, "configuration script (%s) must be an absolute path",
211 		    resolvconf_script);
212 	}
213 	if (pidfilename && *pidfilename != '/') {
214 		errx(1, "pid filename (%s) must be an absolute path",
215 		    pidfilename);
216 	}
217 
218 #if (__FreeBSD_version < 900000)
219 	if (Fflag) {
220 		setinet6sysctl(IPV6CTL_FORWARDING, 0);
221 	} else {
222 		/* warn if forwarding is up */
223 		if (getinet6sysctl(IPV6CTL_FORWARDING))
224 			warnx("kernel is configured as a router, not a host");
225 	}
226 #endif
227 
228 #ifndef SMALL
229 	/* initialization to dump internal status to a file */
230 	signal(SIGUSR1, rtsold_set_dump_file);
231 #endif
232 
233 	if (!fflag)
234 		daemon(0, 0);		/* act as a daemon */
235 
236 	/*
237 	 * Open a socket for sending RS and receiving RA.
238 	 * This should be done before calling ifinit(), since the function
239 	 * uses the socket.
240 	 */
241 	if ((s = sockopen()) < 0) {
242 		warnmsg(LOG_ERR, __func__, "failed to open a socket");
243 		exit(1);
244 	}
245 	set[0].fd = s;
246 	set[0].events = POLLIN;
247 	set[1].fd = -1;
248 
249 	if ((rtsock = rtsock_open()) < 0) {
250 		warnmsg(LOG_ERR, __func__, "failed to open a socket");
251 		exit(1);
252 	}
253 	set[1].fd = rtsock;
254 	set[1].events = POLLIN;
255 
256 	/* configuration per interface */
257 	if (ifinit()) {
258 		warnmsg(LOG_ERR, __func__,
259 		    "failed to initialize interfaces");
260 		exit(1);
261 	}
262 	if (aflag)
263 		argv = autoifprobe();
264 	while (argv && *argv) {
265 		if (ifconfig(*argv)) {
266 			warnmsg(LOG_ERR, __func__,
267 			    "failed to initialize %s", *argv);
268 			exit(1);
269 		}
270 		argv++;
271 	}
272 
273 	/* setup for probing default routers */
274 	if (probe_init()) {
275 		warnmsg(LOG_ERR, __func__,
276 		    "failed to setup for probing routers");
277 		exit(1);
278 		/*NOTREACHED*/
279 	}
280 
281 	/* dump the current pid */
282 	if (!once) {
283 		pid_t pid = getpid();
284 		FILE *fp;
285 
286 		if ((fp = fopen(pidfilename, "w")) == NULL)
287 			warnmsg(LOG_ERR, __func__,
288 			    "failed to open a pid log file(%s): %s",
289 			    pidfilename, strerror(errno));
290 		else {
291 			fprintf(fp, "%d\n", pid);
292 			fclose(fp);
293 		}
294 	}
295 	while (1) {		/* main loop */
296 		int e;
297 #ifndef SMALL
298 		if (do_dump) {	/* SIGUSR1 */
299 			do_dump = 0;
300 			rtsold_dump_file(dumpfilename);
301 		}
302 #endif
303 
304 		timeout = rtsol_check_timer();
305 
306 		if (once) {
307 			struct ifinfo *ifi;
308 
309 			/* if we have no timeout, we are done (or failed) */
310 			if (timeout == NULL)
311 				break;
312 
313 			/* if all interfaces have got RA packet, we are done */
314 			TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
315 				if (ifi->state != IFS_DOWN && ifi->racnt == 0)
316 					break;
317 			}
318 			if (ifi == NULL)
319 				break;
320 		}
321 		e = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + timeout->tv_nsec / 1000 / 1000) : INFTIM);
322 		if (e < 1) {
323 			if (e < 0 && errno != EINTR) {
324 				warnmsg(LOG_ERR, __func__, "select: %s",
325 				    strerror(errno));
326 			}
327 			continue;
328 		}
329 
330 		/* packet reception */
331 		if (set[1].revents & POLLIN)
332 			rtsock_input(rtsock);
333 		if (set[0].revents & POLLIN)
334 			rtsol_input(s);
335 	}
336 	/* NOTREACHED */
337 
338 	return (0);
339 }
340 
341 int
342 ifconfig(char *ifname)
343 {
344 	struct ifinfo *ifi;
345 	struct sockaddr_dl *sdl;
346 	int flags;
347 
348 	if ((sdl = if_nametosdl(ifname)) == NULL) {
349 		warnmsg(LOG_ERR, __func__,
350 		    "failed to get link layer information for %s", ifname);
351 		return (-1);
352 	}
353 	if (find_ifinfo(sdl->sdl_index)) {
354 		warnmsg(LOG_ERR, __func__,
355 		    "interface %s was already configured", ifname);
356 		free(sdl);
357 		return (-1);
358 	}
359 
360 	if (Fflag) {
361 		struct in6_ndireq nd;
362 		int s;
363 
364 		if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
365 			warnmsg(LOG_ERR, __func__, "socket() failed.");
366 			return (-1);
367 		}
368 		memset(&nd, 0, sizeof(nd));
369 		strlcpy(nd.ifname, ifname, sizeof(nd.ifname));
370 		if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
371 			warnmsg(LOG_ERR, __func__,
372 			    "cannot get accept_rtadv flag");
373 			close(s);
374 			return (-1);
375 		}
376 		nd.ndi.flags |= ND6_IFF_ACCEPT_RTADV;
377 		if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd) < 0) {
378 			warnmsg(LOG_ERR, __func__,
379 			    "cannot set accept_rtadv flag");
380 			close(s);
381 			return (-1);
382 		}
383 		close(s);
384 	}
385 
386 	if ((ifi = malloc(sizeof(*ifi))) == NULL) {
387 		warnmsg(LOG_ERR, __func__, "memory allocation failed");
388 		free(sdl);
389 		return (-1);
390 	}
391 	memset(ifi, 0, sizeof(*ifi));
392 	ifi->sdl = sdl;
393 	ifi->ifi_rdnss = IFI_DNSOPT_STATE_NOINFO;
394 	ifi->ifi_dnssl = IFI_DNSOPT_STATE_NOINFO;
395 	TAILQ_INIT(&ifi->ifi_rainfo);
396 	strlcpy(ifi->ifname, ifname, sizeof(ifi->ifname));
397 
398 	/* construct a router solicitation message */
399 	if (make_packet(ifi))
400 		goto bad;
401 
402 	/* set link ID of this interface. */
403 #ifdef HAVE_SCOPELIB
404 	if (inet_zoneid(AF_INET6, 2, ifname, &ifi->linkid))
405 		goto bad;
406 #else
407 	/* XXX: assume interface IDs as link IDs */
408 	ifi->linkid = ifi->sdl->sdl_index;
409 #endif
410 
411 	/*
412 	 * check if the interface is available.
413 	 * also check if SIOCGIFMEDIA ioctl is OK on the interface.
414 	 */
415 	ifi->mediareqok = 1;
416 	ifi->active = interface_status(ifi);
417 	if (!ifi->mediareqok) {
418 		/*
419 		 * probe routers periodically even if the link status
420 		 * does not change.
421 		 */
422 		ifi->probeinterval = PROBE_INTERVAL;
423 	}
424 
425 	/* activate interface: interface_up returns 0 on success */
426 	flags = interface_up(ifi->ifname);
427 	if (flags == 0)
428 		ifi->state = IFS_DELAY;
429 	else if (flags == IFS_TENTATIVE)
430 		ifi->state = IFS_TENTATIVE;
431 	else
432 		ifi->state = IFS_DOWN;
433 
434 	rtsol_timer_update(ifi);
435 
436 	TAILQ_INSERT_TAIL(&ifinfo_head, ifi, ifi_next);
437 	return (0);
438 
439 bad:
440 	free(ifi->sdl);
441 	free(ifi);
442 	return (-1);
443 }
444 
445 void
446 iflist_init(void)
447 {
448 	struct ifinfo *ifi;
449 
450 	while ((ifi = TAILQ_FIRST(&ifinfo_head)) != NULL) {
451 		TAILQ_REMOVE(&ifinfo_head, ifi, ifi_next);
452 		if (ifi->sdl != NULL)
453 			free(ifi->sdl);
454 		if (ifi->rs_data != NULL)
455 			free(ifi->rs_data);
456 		free(ifi);
457 	}
458 }
459 
460 #if 0
461 static int
462 ifreconfig(char *ifname)
463 {
464 	struct ifinfo *ifi, *prev;
465 	int rv;
466 
467 	prev = NULL;
468 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
469 		if (strncmp(ifi->ifname, ifname, sizeof(ifi->ifname)) == 0)
470 			break;
471 		prev = ifi;
472 	}
473 	prev->next = ifi->next;
474 
475 	rv = ifconfig(ifname);
476 
477 	/* reclaim it after ifconfig() in case ifname is pointer inside ifi */
478 	if (ifi->rs_data)
479 		free(ifi->rs_data);
480 	free(ifi->sdl);
481 	free(ifi);
482 
483 	return (rv);
484 }
485 #endif
486 
487 struct rainfo *
488 find_rainfo(struct ifinfo *ifi, struct sockaddr_in6 *sin6)
489 {
490 	struct rainfo *rai;
491 
492 	TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next)
493 		if (memcmp(&rai->rai_saddr.sin6_addr, &sin6->sin6_addr,
494 		    sizeof(rai->rai_saddr.sin6_addr)) == 0)
495 			return (rai);
496 
497 	return (NULL);
498 }
499 
500 struct ifinfo *
501 find_ifinfo(int ifindex)
502 {
503 	struct ifinfo *ifi;
504 
505 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
506 		if (ifi->sdl->sdl_index == ifindex)
507 			return (ifi);
508 	}
509 	return (NULL);
510 }
511 
512 static int
513 make_packet(struct ifinfo *ifi)
514 {
515 	size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
516 	struct nd_router_solicit *rs;
517 	char *buf;
518 
519 	if ((lladdroptlen = lladdropt_length(ifi->sdl)) == 0) {
520 		warnmsg(LOG_INFO, __func__,
521 		    "link-layer address option has null length"
522 		    " on %s. Treat as not included.", ifi->ifname);
523 	}
524 	packlen += lladdroptlen;
525 	ifi->rs_datalen = packlen;
526 
527 	/* allocate buffer */
528 	if ((buf = malloc(packlen)) == NULL) {
529 		warnmsg(LOG_ERR, __func__,
530 		    "memory allocation failed for %s", ifi->ifname);
531 		return (-1);
532 	}
533 	ifi->rs_data = buf;
534 
535 	/* fill in the message */
536 	rs = (struct nd_router_solicit *)buf;
537 	rs->nd_rs_type = ND_ROUTER_SOLICIT;
538 	rs->nd_rs_code = 0;
539 	rs->nd_rs_cksum = 0;
540 	rs->nd_rs_reserved = 0;
541 	buf += sizeof(*rs);
542 
543 	/* fill in source link-layer address option */
544 	if (lladdroptlen)
545 		lladdropt_fill(ifi->sdl, (struct nd_opt_hdr *)buf);
546 
547 	return (0);
548 }
549 
550 static struct timespec *
551 rtsol_check_timer(void)
552 {
553 	static struct timespec returnval;
554 	struct timespec now, rtsol_timer;
555 	struct ifinfo *ifi;
556 	struct rainfo *rai;
557 	struct ra_opt *rao, *raotmp;
558 	int flags;
559 
560 	clock_gettime(CLOCK_MONOTONIC_FAST, &now);
561 
562 	rtsol_timer = tm_max;
563 
564 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
565 		if (TS_CMP(&ifi->expire, &now, <=)) {
566 			warnmsg(LOG_DEBUG, __func__, "timer expiration on %s, "
567 			    "state = %d", ifi->ifname, ifi->state);
568 
569 			while((rai = TAILQ_FIRST(&ifi->ifi_rainfo)) != NULL) {
570 				/* Remove all RA options. */
571 				TAILQ_REMOVE(&ifi->ifi_rainfo, rai, rai_next);
572 				while ((rao = TAILQ_FIRST(&rai->rai_ra_opt)) !=
573 				    NULL) {
574 					TAILQ_REMOVE(&rai->rai_ra_opt, rao,
575 					    rao_next);
576 					if (rao->rao_msg != NULL)
577 						free(rao->rao_msg);
578 					free(rao);
579 				}
580 				free(rai);
581 			}
582 			switch (ifi->state) {
583 			case IFS_DOWN:
584 			case IFS_TENTATIVE:
585 				/* interface_up returns 0 on success */
586 				flags = interface_up(ifi->ifname);
587 				if (flags == 0)
588 					ifi->state = IFS_DELAY;
589 				else if (flags == IFS_TENTATIVE)
590 					ifi->state = IFS_TENTATIVE;
591 				else
592 					ifi->state = IFS_DOWN;
593 				break;
594 			case IFS_IDLE:
595 			{
596 				int oldstatus = ifi->active;
597 				int probe = 0;
598 
599 				ifi->active = interface_status(ifi);
600 
601 				if (oldstatus != ifi->active) {
602 					warnmsg(LOG_DEBUG, __func__,
603 					    "%s status is changed"
604 					    " from %d to %d",
605 					    ifi->ifname,
606 					    oldstatus, ifi->active);
607 					probe = 1;
608 					ifi->state = IFS_DELAY;
609 				} else if (ifi->probeinterval &&
610 				    (ifi->probetimer -=
611 				    ifi->timer.tv_sec) <= 0) {
612 					/* probe timer expired */
613 					ifi->probetimer =
614 					    ifi->probeinterval;
615 					probe = 1;
616 					ifi->state = IFS_PROBE;
617 				}
618 
619 				/*
620 				 * If we need a probe, clear the previous
621 				 * status wrt the "other" configuration.
622 				 */
623 				if (probe)
624 					ifi->otherconfig = 0;
625 
626 				if (probe && mobile_node)
627 					defrouter_probe(ifi);
628 				break;
629 			}
630 			case IFS_DELAY:
631 				ifi->state = IFS_PROBE;
632 				sendpacket(ifi);
633 				break;
634 			case IFS_PROBE:
635 				if (ifi->probes < MAX_RTR_SOLICITATIONS)
636 					sendpacket(ifi);
637 				else {
638 					warnmsg(LOG_INFO, __func__,
639 					    "No answer after sending %d RSs",
640 					    ifi->probes);
641 					ifi->probes = 0;
642 					ifi->state = IFS_IDLE;
643 				}
644 				break;
645 			}
646 			rtsol_timer_update(ifi);
647 		} else {
648 			/* Expiration check for RA options. */
649 			int expire = 0;
650 
651 			TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next) {
652 				TAILQ_FOREACH_SAFE(rao, &rai->rai_ra_opt,
653 				    rao_next, raotmp) {
654 					warnmsg(LOG_DEBUG, __func__,
655 					    "RA expiration timer: "
656 					    "type=%d, msg=%s, expire=%s",
657 					    rao->rao_type, (char *)rao->rao_msg,
658 						sec2str(&rao->rao_expire));
659 					if (TS_CMP(&now, &rao->rao_expire,
660 					    >=)) {
661 						warnmsg(LOG_DEBUG, __func__,
662 						    "RA expiration timer: "
663 						    "expired.");
664 						TAILQ_REMOVE(&rai->rai_ra_opt,
665 						    rao, rao_next);
666 						if (rao->rao_msg != NULL)
667 							free(rao->rao_msg);
668 						free(rao);
669 						expire = 1;
670 					}
671 				}
672 			}
673 			if (expire)
674 				ra_opt_handler(ifi);
675 		}
676 		if (TS_CMP(&ifi->expire, &rtsol_timer, <))
677 			rtsol_timer = ifi->expire;
678 	}
679 
680 	if (TS_CMP(&rtsol_timer, &tm_max, ==)) {
681 		warnmsg(LOG_DEBUG, __func__, "there is no timer");
682 		return (NULL);
683 	} else if (TS_CMP(&rtsol_timer, &now, <))
684 		/* this may occur when the interval is too small */
685 		returnval.tv_sec = returnval.tv_nsec = 0;
686 	else
687 		TS_SUB(&rtsol_timer, &now, &returnval);
688 
689 	now.tv_sec += returnval.tv_sec;
690 	now.tv_nsec += returnval.tv_nsec;
691 	warnmsg(LOG_DEBUG, __func__, "New timer is %s",
692 	    sec2str(&now));
693 
694 	return (&returnval);
695 }
696 
697 void
698 rtsol_timer_update(struct ifinfo *ifi)
699 {
700 #define MILLION 1000000
701 #define DADRETRY 10		/* XXX: adhoc */
702 	long interval;
703 	struct timespec now;
704 
705 	bzero(&ifi->timer, sizeof(ifi->timer));
706 
707 	switch (ifi->state) {
708 	case IFS_DOWN:
709 	case IFS_TENTATIVE:
710 		if (++ifi->dadcount > DADRETRY) {
711 			ifi->dadcount = 0;
712 			ifi->timer.tv_sec = PROBE_INTERVAL;
713 		} else
714 			ifi->timer.tv_sec = 1;
715 		break;
716 	case IFS_IDLE:
717 		if (mobile_node) {
718 			/* XXX should be configurable */
719 			ifi->timer.tv_sec = 3;
720 		}
721 		else
722 			ifi->timer = tm_max;	/* stop timer(valid?) */
723 		break;
724 	case IFS_DELAY:
725 		interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
726 		ifi->timer.tv_sec = interval / MILLION;
727 		ifi->timer.tv_nsec = (interval % MILLION) * 1000;
728 		break;
729 	case IFS_PROBE:
730 		if (ifi->probes < MAX_RTR_SOLICITATIONS)
731 			ifi->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
732 		else {
733 			/*
734 			 * After sending MAX_RTR_SOLICITATIONS solicitations,
735 			 * we're just waiting for possible replies; there
736 			 * will be no more solicitation.  Thus, we change
737 			 * the timer value to MAX_RTR_SOLICITATION_DELAY based
738 			 * on RFC 2461, Section 6.3.7.
739 			 */
740 			ifi->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
741 		}
742 		break;
743 	default:
744 		warnmsg(LOG_ERR, __func__,
745 		    "illegal interface state(%d) on %s",
746 		    ifi->state, ifi->ifname);
747 		return;
748 	}
749 
750 	/* reset the timer */
751 	if (TS_CMP(&ifi->timer, &tm_max, ==)) {
752 		ifi->expire = tm_max;
753 		warnmsg(LOG_DEBUG, __func__,
754 		    "stop timer for %s", ifi->ifname);
755 	} else {
756 		clock_gettime(CLOCK_MONOTONIC_FAST, &now);
757 		TS_ADD(&now, &ifi->timer, &ifi->expire);
758 
759 		now.tv_sec += ifi->timer.tv_sec;
760 		now.tv_nsec += ifi->timer.tv_nsec;
761 		warnmsg(LOG_DEBUG, __func__, "set timer for %s to %s",
762 		    ifi->ifname, sec2str(&now));
763 	}
764 
765 #undef MILLION
766 }
767 
768 /* timer related utility functions */
769 #define MILLION 1000000
770 
771 #ifndef SMALL
772 static void
773 rtsold_set_dump_file(int sig __unused)
774 {
775 	do_dump = 1;
776 }
777 #endif
778 
779 static void
780 usage(void)
781 {
782 #ifndef SMALL
783 	fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
784 	    "[-p pidfile] [-R script-name] interface ...\n");
785 	fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
786 	    "[-p pidfile] [-R script-name] -a\n");
787 #else
788 	fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
789 	    "[-p pidfile] [-R script-name] interface ...\n");
790 	fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
791 	    "[-p pidfile] [-R script-name] -a\n");
792 #endif
793 }
794 
795 void
796 warnmsg(int priority, const char *func, const char *msg, ...)
797 {
798 	va_list ap;
799 	char buf[BUFSIZ];
800 
801 	va_start(ap, msg);
802 	if (fflag) {
803 		if (priority <= log_upto) {
804 			(void)vfprintf(stderr, msg, ap);
805 			(void)fprintf(stderr, "\n");
806 		}
807 	} else {
808 		snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
809 		msg = buf;
810 		vsyslog(priority, msg, ap);
811 	}
812 	va_end(ap);
813 }
814 
815 /*
816  * return a list of interfaces which is suitable to sending an RS.
817  */
818 char **
819 autoifprobe(void)
820 {
821 	static char **argv = NULL;
822 	static int n = 0;
823 	char **a;
824 	int s = 0, i, found;
825 	struct ifaddrs *ifap, *ifa;
826 	struct in6_ndireq nd;
827 
828 	/* initialize */
829 	while (n--)
830 		free(argv[n]);
831 	if (argv) {
832 		free(argv);
833 		argv = NULL;
834 	}
835 	n = 0;
836 
837 	if (getifaddrs(&ifap) != 0)
838 		return (NULL);
839 
840 	if (!Fflag && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
841 		warnmsg(LOG_ERR, __func__, "socket");
842 		exit(1);
843 	}
844 
845 	/* find an ethernet */
846 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
847 		if ((ifa->ifa_flags & IFF_UP) == 0)
848 			continue;
849 		if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
850 			continue;
851 		if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
852 			continue;
853 		if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
854 			continue;
855 
856 		if (ifa->ifa_addr->sa_family != AF_INET6)
857 			continue;
858 
859 		found = 0;
860 		for (i = 0; i < n; i++) {
861 			if (strcmp(argv[i], ifa->ifa_name) == 0) {
862 				found++;
863 				break;
864 			}
865 		}
866 		if (found)
867 			continue;
868 
869 		/*
870 		 * Skip the interfaces which IPv6 and/or accepting RA
871 		 * is disabled.
872 		 */
873 		if (!Fflag) {
874 			memset(&nd, 0, sizeof(nd));
875 			strlcpy(nd.ifname, ifa->ifa_name, sizeof(nd.ifname));
876 			if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
877 				warnmsg(LOG_ERR, __func__,
878 					"ioctl(SIOCGIFINFO_IN6)");
879 				exit(1);
880 			}
881 			if ((nd.ndi.flags & ND6_IFF_IFDISABLED))
882 				continue;
883 			if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV))
884 				continue;
885 		}
886 
887 		/* if we find multiple candidates, just warn. */
888 		if (n != 0 && dflag > 1)
889 			warnmsg(LOG_WARNING, __func__,
890 				"multiple interfaces found");
891 
892 		a = realloc(argv, (n + 1) * sizeof(char *));
893 		if (a == NULL) {
894 			warnmsg(LOG_ERR, __func__, "realloc");
895 			exit(1);
896 		}
897 		argv = a;
898 		argv[n] = strdup(ifa->ifa_name);
899 		if (!argv[n]) {
900 			warnmsg(LOG_ERR, __func__, "malloc");
901 			exit(1);
902 		}
903 		n++;
904 	}
905 
906 	if (n) {
907 		a = realloc(argv, (n + 1) * sizeof(char *));
908 		if (a == NULL) {
909 			warnmsg(LOG_ERR, __func__, "realloc");
910 			exit(1);
911 		}
912 		argv = a;
913 		argv[n] = NULL;
914 
915 		if (dflag > 0) {
916 			for (i = 0; i < n; i++)
917 				warnmsg(LOG_WARNING, __func__, "probing %s",
918 					argv[i]);
919 		}
920 	}
921 	if (!Fflag)
922 		close(s);
923 	freeifaddrs(ifap);
924 	return (argv);
925 }
926