xref: /freebsd/usr.sbin/rtsold/rtsold.c (revision e796cc77c586c2955b2f3940dbf4991b31e8d289)
1 /*	$KAME: rtsold.c,v 1.67 2003/05/17 18:16:15 itojun Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * $FreeBSD$
34  */
35 
36 #include <sys/types.h>
37 #include <sys/ioctl.h>
38 #include <sys/socket.h>
39 #include <sys/param.h>
40 
41 #include <net/if.h>
42 #include <net/if_dl.h>
43 
44 #include <netinet/in.h>
45 #include <netinet/icmp6.h>
46 #include <netinet/in_var.h>
47 #include <arpa/inet.h>
48 
49 #include <netinet6/nd6.h>
50 
51 #include <signal.h>
52 #include <unistd.h>
53 #include <syslog.h>
54 #include <string.h>
55 #include <stdlib.h>
56 #include <stdio.h>
57 #include <time.h>
58 #include <errno.h>
59 #include <err.h>
60 #include <stdarg.h>
61 #include <ifaddrs.h>
62 #include <poll.h>
63 
64 #include "rtsold.h"
65 
66 #define RTSOL_DUMPFILE	"/var/run/rtsold.dump";
67 #define RTSOL_PIDFILE	"/var/run/rtsold.pid";
68 
69 struct timespec tm_max;
70 static int log_upto = 999;
71 static int fflag = 0;
72 
73 int Fflag = 0;	/* force setting sysctl parameters */
74 int aflag = 0;
75 int dflag = 0;
76 int uflag = 0;
77 
78 const char *otherconf_script;
79 const char *resolvconf_script = "/sbin/resolvconf";
80 
81 /* protocol constants */
82 #define MAX_RTR_SOLICITATION_DELAY	1 /* second */
83 #define RTR_SOLICITATION_INTERVAL	4 /* seconds */
84 #define MAX_RTR_SOLICITATIONS		3 /* times */
85 
86 /*
87  * implementation dependent constants in seconds
88  * XXX: should be configurable
89  */
90 #define PROBE_INTERVAL 60
91 
92 /* static variables and functions */
93 static int mobile_node = 0;
94 static const char *pidfilename = RTSOL_PIDFILE;
95 
96 #ifndef SMALL
97 static int do_dump;
98 static const char *dumpfilename = RTSOL_DUMPFILE;
99 #endif
100 
101 #if 0
102 static int ifreconfig(char *);
103 #endif
104 
105 static int make_packet(struct ifinfo *);
106 static struct timespec *rtsol_check_timer(void);
107 
108 #ifndef SMALL
109 static void rtsold_set_dump_file(int);
110 #endif
111 static void usage(void);
112 
113 int
114 main(int argc, char **argv)
115 {
116 	int s, ch, once = 0;
117 	struct timespec *timeout;
118 	const char *opts;
119 	struct pollfd set[2];
120 	int rtsock;
121 	char *argv0;
122 
123 #ifndef SMALL
124 	/* rtsold */
125 	opts = "adDfFm1O:p:R:u";
126 #else
127 	/* rtsol */
128 	opts = "adDFO:R:u";
129 	fflag = 1;
130 	once = 1;
131 #endif
132 	argv0 = argv[0];
133 
134 	while ((ch = getopt(argc, argv, opts)) != -1) {
135 		switch (ch) {
136 		case 'a':
137 			aflag = 1;
138 			break;
139 		case 'd':
140 			dflag += 1;
141 			break;
142 		case 'D':
143 			dflag += 2;
144 			break;
145 		case 'f':
146 			fflag = 1;
147 			break;
148 		case 'F':
149 			Fflag = 1;
150 			break;
151 		case 'm':
152 			mobile_node = 1;
153 			break;
154 		case '1':
155 			once = 1;
156 			break;
157 		case 'O':
158 			otherconf_script = optarg;
159 			break;
160 		case 'p':
161 			pidfilename = optarg;
162 			break;
163 		case 'R':
164 			resolvconf_script = optarg;
165 			break;
166 		case 'u':
167 			uflag = 1;
168 			break;
169 		default:
170 			usage();
171 			exit(1);
172 		}
173 	}
174 	argc -= optind;
175 	argv += optind;
176 
177 	if ((!aflag && argc == 0) || (aflag && argc != 0)) {
178 		usage();
179 		exit(1);
180 	}
181 
182 	/* Generate maximum time in timespec. */
183 	tm_max.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
184 	tm_max.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
185 
186 	/* set log level */
187 	if (dflag > 1)
188 		log_upto = LOG_DEBUG;
189 	else if (dflag > 0)
190 		log_upto = LOG_INFO;
191 	else
192 		log_upto = LOG_NOTICE;
193 
194 	if (!fflag) {
195 		char *ident;
196 
197 		ident = strrchr(argv0, '/');
198 		if (!ident)
199 			ident = argv0;
200 		else
201 			ident++;
202 		openlog(ident, LOG_NDELAY|LOG_PID, LOG_DAEMON);
203 		if (log_upto >= 0)
204 			setlogmask(LOG_UPTO(log_upto));
205 	}
206 
207 	if (otherconf_script && *otherconf_script != '/') {
208 		errx(1, "configuration script (%s) must be an absolute path",
209 		    otherconf_script);
210 	}
211 	if (resolvconf_script && *resolvconf_script != '/') {
212 		errx(1, "configuration script (%s) must be an absolute path",
213 		    resolvconf_script);
214 	}
215 	if (pidfilename && *pidfilename != '/') {
216 		errx(1, "pid filename (%s) must be an absolute path",
217 		    pidfilename);
218 	}
219 
220 #if (__FreeBSD_version < 900000)
221 	if (Fflag) {
222 		setinet6sysctl(IPV6CTL_FORWARDING, 0);
223 	} else {
224 		/* warn if forwarding is up */
225 		if (getinet6sysctl(IPV6CTL_FORWARDING))
226 			warnx("kernel is configured as a router, not a host");
227 	}
228 #endif
229 
230 #ifndef SMALL
231 	/* initialization to dump internal status to a file */
232 	signal(SIGUSR1, rtsold_set_dump_file);
233 #endif
234 
235 	if (!fflag)
236 		daemon(0, 0);		/* act as a daemon */
237 
238 	/*
239 	 * Open a socket for sending RS and receiving RA.
240 	 * This should be done before calling ifinit(), since the function
241 	 * uses the socket.
242 	 */
243 	if ((s = sockopen()) < 0) {
244 		warnmsg(LOG_ERR, __func__, "failed to open a socket");
245 		exit(1);
246 	}
247 	set[0].fd = s;
248 	set[0].events = POLLIN;
249 	set[1].fd = -1;
250 
251 	if ((rtsock = rtsock_open()) < 0) {
252 		warnmsg(LOG_ERR, __func__, "failed to open a socket");
253 		exit(1);
254 	}
255 	set[1].fd = rtsock;
256 	set[1].events = POLLIN;
257 
258 	/* configuration per interface */
259 	if (ifinit()) {
260 		warnmsg(LOG_ERR, __func__,
261 		    "failed to initialize interfaces");
262 		exit(1);
263 	}
264 	if (aflag)
265 		argv = autoifprobe();
266 	while (argv && *argv) {
267 		if (ifconfig(*argv)) {
268 			warnmsg(LOG_ERR, __func__,
269 			    "failed to initialize %s", *argv);
270 			exit(1);
271 		}
272 		argv++;
273 	}
274 
275 	/* setup for probing default routers */
276 	if (probe_init()) {
277 		warnmsg(LOG_ERR, __func__,
278 		    "failed to setup for probing routers");
279 		exit(1);
280 		/*NOTREACHED*/
281 	}
282 
283 	/* dump the current pid */
284 	if (!once) {
285 		pid_t pid = getpid();
286 		FILE *fp;
287 
288 		if ((fp = fopen(pidfilename, "w")) == NULL)
289 			warnmsg(LOG_ERR, __func__,
290 			    "failed to open a pid log file(%s): %s",
291 			    pidfilename, strerror(errno));
292 		else {
293 			fprintf(fp, "%d\n", pid);
294 			fclose(fp);
295 		}
296 	}
297 	while (1) {		/* main loop */
298 		int e;
299 #ifndef SMALL
300 		if (do_dump) {	/* SIGUSR1 */
301 			do_dump = 0;
302 			rtsold_dump_file(dumpfilename);
303 		}
304 #endif
305 
306 		timeout = rtsol_check_timer();
307 
308 		if (once) {
309 			struct ifinfo *ifi;
310 
311 			/* if we have no timeout, we are done (or failed) */
312 			if (timeout == NULL)
313 				break;
314 
315 			/* if all interfaces have got RA packet, we are done */
316 			TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
317 				if (ifi->state != IFS_DOWN && ifi->racnt == 0)
318 					break;
319 			}
320 			if (ifi == NULL)
321 				break;
322 		}
323 		e = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + timeout->tv_nsec / 1000 / 1000) : INFTIM);
324 		if (e < 1) {
325 			if (e < 0 && errno != EINTR) {
326 				warnmsg(LOG_ERR, __func__, "select: %s",
327 				    strerror(errno));
328 			}
329 			continue;
330 		}
331 
332 		/* packet reception */
333 		if (set[1].revents & POLLIN)
334 			rtsock_input(rtsock);
335 		if (set[0].revents & POLLIN)
336 			rtsol_input(s);
337 	}
338 	/* NOTREACHED */
339 
340 	return (0);
341 }
342 
343 int
344 ifconfig(char *ifname)
345 {
346 	struct ifinfo *ifi;
347 	struct sockaddr_dl *sdl;
348 	int flags;
349 
350 	if ((sdl = if_nametosdl(ifname)) == NULL) {
351 		warnmsg(LOG_ERR, __func__,
352 		    "failed to get link layer information for %s", ifname);
353 		return (-1);
354 	}
355 	if (find_ifinfo(sdl->sdl_index)) {
356 		warnmsg(LOG_ERR, __func__,
357 		    "interface %s was already configured", ifname);
358 		free(sdl);
359 		return (-1);
360 	}
361 
362 	if (Fflag) {
363 		struct in6_ndireq nd;
364 		int s;
365 
366 		if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
367 			warnmsg(LOG_ERR, __func__, "socket() failed.");
368 			return (-1);
369 		}
370 		memset(&nd, 0, sizeof(nd));
371 		strlcpy(nd.ifname, ifname, sizeof(nd.ifname));
372 		if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
373 			warnmsg(LOG_ERR, __func__,
374 			    "cannot get accept_rtadv flag");
375 			close(s);
376 			return (-1);
377 		}
378 		nd.ndi.flags |= ND6_IFF_ACCEPT_RTADV;
379 		if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd) < 0) {
380 			warnmsg(LOG_ERR, __func__,
381 			    "cannot set accept_rtadv flag");
382 			close(s);
383 			return (-1);
384 		}
385 		close(s);
386 	}
387 
388 	if ((ifi = malloc(sizeof(*ifi))) == NULL) {
389 		warnmsg(LOG_ERR, __func__, "memory allocation failed");
390 		free(sdl);
391 		return (-1);
392 	}
393 	memset(ifi, 0, sizeof(*ifi));
394 	ifi->sdl = sdl;
395 	ifi->ifi_rdnss = IFI_DNSOPT_STATE_NOINFO;
396 	ifi->ifi_dnssl = IFI_DNSOPT_STATE_NOINFO;
397 	TAILQ_INIT(&ifi->ifi_rainfo);
398 	strlcpy(ifi->ifname, ifname, sizeof(ifi->ifname));
399 
400 	/* construct a router solicitation message */
401 	if (make_packet(ifi))
402 		goto bad;
403 
404 	/* set link ID of this interface. */
405 #ifdef HAVE_SCOPELIB
406 	if (inet_zoneid(AF_INET6, 2, ifname, &ifi->linkid))
407 		goto bad;
408 #else
409 	/* XXX: assume interface IDs as link IDs */
410 	ifi->linkid = ifi->sdl->sdl_index;
411 #endif
412 
413 	/*
414 	 * check if the interface is available.
415 	 * also check if SIOCGIFMEDIA ioctl is OK on the interface.
416 	 */
417 	ifi->mediareqok = 1;
418 	ifi->active = interface_status(ifi);
419 	if (!ifi->mediareqok) {
420 		/*
421 		 * probe routers periodically even if the link status
422 		 * does not change.
423 		 */
424 		ifi->probeinterval = PROBE_INTERVAL;
425 	}
426 
427 	/* activate interface: interface_up returns 0 on success */
428 	flags = interface_up(ifi->ifname);
429 	if (flags == 0)
430 		ifi->state = IFS_DELAY;
431 	else if (flags == IFS_TENTATIVE)
432 		ifi->state = IFS_TENTATIVE;
433 	else
434 		ifi->state = IFS_DOWN;
435 
436 	rtsol_timer_update(ifi);
437 
438 	TAILQ_INSERT_TAIL(&ifinfo_head, ifi, ifi_next);
439 	return (0);
440 
441 bad:
442 	free(ifi->sdl);
443 	free(ifi);
444 	return (-1);
445 }
446 
447 void
448 iflist_init(void)
449 {
450 	struct ifinfo *ifi;
451 
452 	while ((ifi = TAILQ_FIRST(&ifinfo_head)) != NULL) {
453 		TAILQ_REMOVE(&ifinfo_head, ifi, ifi_next);
454 		if (ifi->sdl != NULL)
455 			free(ifi->sdl);
456 		if (ifi->rs_data != NULL)
457 			free(ifi->rs_data);
458 		free(ifi);
459 	}
460 }
461 
462 #if 0
463 static int
464 ifreconfig(char *ifname)
465 {
466 	struct ifinfo *ifi, *prev;
467 	int rv;
468 
469 	prev = NULL;
470 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
471 		if (strncmp(ifi->ifname, ifname, sizeof(ifi->ifname)) == 0)
472 			break;
473 		prev = ifi;
474 	}
475 	prev->next = ifi->next;
476 
477 	rv = ifconfig(ifname);
478 
479 	/* reclaim it after ifconfig() in case ifname is pointer inside ifi */
480 	if (ifi->rs_data)
481 		free(ifi->rs_data);
482 	free(ifi->sdl);
483 	free(ifi);
484 
485 	return (rv);
486 }
487 #endif
488 
489 struct rainfo *
490 find_rainfo(struct ifinfo *ifi, struct sockaddr_in6 *sin6)
491 {
492 	struct rainfo *rai;
493 
494 	TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next)
495 		if (memcmp(&rai->rai_saddr.sin6_addr, &sin6->sin6_addr,
496 		    sizeof(rai->rai_saddr.sin6_addr)) == 0)
497 			return (rai);
498 
499 	return (NULL);
500 }
501 
502 struct ifinfo *
503 find_ifinfo(int ifindex)
504 {
505 	struct ifinfo *ifi;
506 
507 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
508 		if (ifi->sdl->sdl_index == ifindex)
509 			return (ifi);
510 	}
511 	return (NULL);
512 }
513 
514 static int
515 make_packet(struct ifinfo *ifi)
516 {
517 	size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
518 	struct nd_router_solicit *rs;
519 	char *buf;
520 
521 	if ((lladdroptlen = lladdropt_length(ifi->sdl)) == 0) {
522 		warnmsg(LOG_INFO, __func__,
523 		    "link-layer address option has null length"
524 		    " on %s. Treat as not included.", ifi->ifname);
525 	}
526 	packlen += lladdroptlen;
527 	ifi->rs_datalen = packlen;
528 
529 	/* allocate buffer */
530 	if ((buf = malloc(packlen)) == NULL) {
531 		warnmsg(LOG_ERR, __func__,
532 		    "memory allocation failed for %s", ifi->ifname);
533 		return (-1);
534 	}
535 	ifi->rs_data = buf;
536 
537 	/* fill in the message */
538 	rs = (struct nd_router_solicit *)buf;
539 	rs->nd_rs_type = ND_ROUTER_SOLICIT;
540 	rs->nd_rs_code = 0;
541 	rs->nd_rs_cksum = 0;
542 	rs->nd_rs_reserved = 0;
543 	buf += sizeof(*rs);
544 
545 	/* fill in source link-layer address option */
546 	if (lladdroptlen)
547 		lladdropt_fill(ifi->sdl, (struct nd_opt_hdr *)buf);
548 
549 	return (0);
550 }
551 
552 static struct timespec *
553 rtsol_check_timer(void)
554 {
555 	static struct timespec returnval;
556 	struct timespec now, rtsol_timer;
557 	struct ifinfo *ifi;
558 	struct rainfo *rai;
559 	struct ra_opt *rao, *raotmp;
560 	int flags;
561 
562 	clock_gettime(CLOCK_MONOTONIC_FAST, &now);
563 
564 	rtsol_timer = tm_max;
565 
566 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
567 		if (TS_CMP(&ifi->expire, &now, <=)) {
568 			warnmsg(LOG_DEBUG, __func__, "timer expiration on %s, "
569 			    "state = %d", ifi->ifname, ifi->state);
570 
571 			while((rai = TAILQ_FIRST(&ifi->ifi_rainfo)) != NULL) {
572 				/* Remove all RA options. */
573 				TAILQ_REMOVE(&ifi->ifi_rainfo, rai, rai_next);
574 				while ((rao = TAILQ_FIRST(&rai->rai_ra_opt)) !=
575 				    NULL) {
576 					TAILQ_REMOVE(&rai->rai_ra_opt, rao,
577 					    rao_next);
578 					if (rao->rao_msg != NULL)
579 						free(rao->rao_msg);
580 					free(rao);
581 				}
582 				free(rai);
583 			}
584 			switch (ifi->state) {
585 			case IFS_DOWN:
586 			case IFS_TENTATIVE:
587 				/* interface_up returns 0 on success */
588 				flags = interface_up(ifi->ifname);
589 				if (flags == 0)
590 					ifi->state = IFS_DELAY;
591 				else if (flags == IFS_TENTATIVE)
592 					ifi->state = IFS_TENTATIVE;
593 				else
594 					ifi->state = IFS_DOWN;
595 				break;
596 			case IFS_IDLE:
597 			{
598 				int oldstatus = ifi->active;
599 				int probe = 0;
600 
601 				ifi->active = interface_status(ifi);
602 
603 				if (oldstatus != ifi->active) {
604 					warnmsg(LOG_DEBUG, __func__,
605 					    "%s status is changed"
606 					    " from %d to %d",
607 					    ifi->ifname,
608 					    oldstatus, ifi->active);
609 					probe = 1;
610 					ifi->state = IFS_DELAY;
611 				} else if (ifi->probeinterval &&
612 				    (ifi->probetimer -=
613 				    ifi->timer.tv_sec) <= 0) {
614 					/* probe timer expired */
615 					ifi->probetimer =
616 					    ifi->probeinterval;
617 					probe = 1;
618 					ifi->state = IFS_PROBE;
619 				}
620 
621 				/*
622 				 * If we need a probe, clear the previous
623 				 * status wrt the "other" configuration.
624 				 */
625 				if (probe)
626 					ifi->otherconfig = 0;
627 
628 				if (probe && mobile_node)
629 					defrouter_probe(ifi);
630 				break;
631 			}
632 			case IFS_DELAY:
633 				ifi->state = IFS_PROBE;
634 				sendpacket(ifi);
635 				break;
636 			case IFS_PROBE:
637 				if (ifi->probes < MAX_RTR_SOLICITATIONS)
638 					sendpacket(ifi);
639 				else {
640 					warnmsg(LOG_INFO, __func__,
641 					    "No answer after sending %d RSs",
642 					    ifi->probes);
643 					ifi->probes = 0;
644 					ifi->state = IFS_IDLE;
645 				}
646 				break;
647 			}
648 			rtsol_timer_update(ifi);
649 		} else {
650 			/* Expiration check for RA options. */
651 			int expire = 0;
652 
653 			TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next) {
654 				TAILQ_FOREACH_SAFE(rao, &rai->rai_ra_opt,
655 				    rao_next, raotmp) {
656 					warnmsg(LOG_DEBUG, __func__,
657 					    "RA expiration timer: "
658 					    "type=%d, msg=%s, expire=%s",
659 					    rao->rao_type, (char *)rao->rao_msg,
660 						sec2str(&rao->rao_expire));
661 					if (TS_CMP(&now, &rao->rao_expire,
662 					    >=)) {
663 						warnmsg(LOG_DEBUG, __func__,
664 						    "RA expiration timer: "
665 						    "expired.");
666 						TAILQ_REMOVE(&rai->rai_ra_opt,
667 						    rao, rao_next);
668 						if (rao->rao_msg != NULL)
669 							free(rao->rao_msg);
670 						free(rao);
671 						expire = 1;
672 					}
673 				}
674 			}
675 			if (expire)
676 				ra_opt_handler(ifi);
677 		}
678 		if (TS_CMP(&ifi->expire, &rtsol_timer, <))
679 			rtsol_timer = ifi->expire;
680 	}
681 
682 	if (TS_CMP(&rtsol_timer, &tm_max, ==)) {
683 		warnmsg(LOG_DEBUG, __func__, "there is no timer");
684 		return (NULL);
685 	} else if (TS_CMP(&rtsol_timer, &now, <))
686 		/* this may occur when the interval is too small */
687 		returnval.tv_sec = returnval.tv_nsec = 0;
688 	else
689 		TS_SUB(&rtsol_timer, &now, &returnval);
690 
691 	now.tv_sec += returnval.tv_sec;
692 	now.tv_nsec += returnval.tv_nsec;
693 	warnmsg(LOG_DEBUG, __func__, "New timer is %s",
694 	    sec2str(&now));
695 
696 	return (&returnval);
697 }
698 
699 void
700 rtsol_timer_update(struct ifinfo *ifi)
701 {
702 #define MILLION 1000000
703 #define DADRETRY 10		/* XXX: adhoc */
704 	long interval;
705 	struct timespec now;
706 
707 	bzero(&ifi->timer, sizeof(ifi->timer));
708 
709 	switch (ifi->state) {
710 	case IFS_DOWN:
711 	case IFS_TENTATIVE:
712 		if (++ifi->dadcount > DADRETRY) {
713 			ifi->dadcount = 0;
714 			ifi->timer.tv_sec = PROBE_INTERVAL;
715 		} else
716 			ifi->timer.tv_sec = 1;
717 		break;
718 	case IFS_IDLE:
719 		if (mobile_node) {
720 			/* XXX should be configurable */
721 			ifi->timer.tv_sec = 3;
722 		}
723 		else
724 			ifi->timer = tm_max;	/* stop timer(valid?) */
725 		break;
726 	case IFS_DELAY:
727 		interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
728 		ifi->timer.tv_sec = interval / MILLION;
729 		ifi->timer.tv_nsec = (interval % MILLION) * 1000;
730 		break;
731 	case IFS_PROBE:
732 		if (ifi->probes < MAX_RTR_SOLICITATIONS)
733 			ifi->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
734 		else {
735 			/*
736 			 * After sending MAX_RTR_SOLICITATIONS solicitations,
737 			 * we're just waiting for possible replies; there
738 			 * will be no more solicitation.  Thus, we change
739 			 * the timer value to MAX_RTR_SOLICITATION_DELAY based
740 			 * on RFC 2461, Section 6.3.7.
741 			 */
742 			ifi->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
743 		}
744 		break;
745 	default:
746 		warnmsg(LOG_ERR, __func__,
747 		    "illegal interface state(%d) on %s",
748 		    ifi->state, ifi->ifname);
749 		return;
750 	}
751 
752 	/* reset the timer */
753 	if (TS_CMP(&ifi->timer, &tm_max, ==)) {
754 		ifi->expire = tm_max;
755 		warnmsg(LOG_DEBUG, __func__,
756 		    "stop timer for %s", ifi->ifname);
757 	} else {
758 		clock_gettime(CLOCK_MONOTONIC_FAST, &now);
759 		TS_ADD(&now, &ifi->timer, &ifi->expire);
760 
761 		now.tv_sec += ifi->timer.tv_sec;
762 		now.tv_nsec += ifi->timer.tv_nsec;
763 		warnmsg(LOG_DEBUG, __func__, "set timer for %s to %s",
764 		    ifi->ifname, sec2str(&now));
765 	}
766 
767 #undef MILLION
768 }
769 
770 /* timer related utility functions */
771 #define MILLION 1000000
772 
773 #ifndef SMALL
774 static void
775 rtsold_set_dump_file(int sig __unused)
776 {
777 	do_dump = 1;
778 }
779 #endif
780 
781 static void
782 usage(void)
783 {
784 #ifndef SMALL
785 	fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
786 	    "[-p pidfile] [-R script-name] interface ...\n");
787 	fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
788 	    "[-p pidfile] [-R script-name] -a\n");
789 #else
790 	fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
791 	    "[-p pidfile] [-R script-name] interface ...\n");
792 	fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
793 	    "[-p pidfile] [-R script-name] -a\n");
794 #endif
795 }
796 
797 void
798 warnmsg(int priority, const char *func, const char *msg, ...)
799 {
800 	va_list ap;
801 	char buf[BUFSIZ];
802 
803 	va_start(ap, msg);
804 	if (fflag) {
805 		if (priority <= log_upto) {
806 			(void)vfprintf(stderr, msg, ap);
807 			(void)fprintf(stderr, "\n");
808 		}
809 	} else {
810 		snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
811 		msg = buf;
812 		vsyslog(priority, msg, ap);
813 	}
814 	va_end(ap);
815 }
816 
817 /*
818  * return a list of interfaces which is suitable to sending an RS.
819  */
820 char **
821 autoifprobe(void)
822 {
823 	static char **argv = NULL;
824 	static int n = 0;
825 	char **a;
826 	int s = 0, i, found;
827 	struct ifaddrs *ifap, *ifa;
828 	struct in6_ndireq nd;
829 
830 	/* initialize */
831 	while (n--)
832 		free(argv[n]);
833 	if (argv) {
834 		free(argv);
835 		argv = NULL;
836 	}
837 	n = 0;
838 
839 	if (getifaddrs(&ifap) != 0)
840 		return (NULL);
841 
842 	if (!Fflag && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
843 		warnmsg(LOG_ERR, __func__, "socket");
844 		exit(1);
845 	}
846 
847 	/* find an ethernet */
848 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
849 		if ((ifa->ifa_flags & IFF_UP) == 0)
850 			continue;
851 		if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
852 			continue;
853 		if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
854 			continue;
855 		if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
856 			continue;
857 
858 		if (ifa->ifa_addr->sa_family != AF_INET6)
859 			continue;
860 
861 		found = 0;
862 		for (i = 0; i < n; i++) {
863 			if (strcmp(argv[i], ifa->ifa_name) == 0) {
864 				found++;
865 				break;
866 			}
867 		}
868 		if (found)
869 			continue;
870 
871 		/*
872 		 * Skip the interfaces which IPv6 and/or accepting RA
873 		 * is disabled.
874 		 */
875 		if (!Fflag) {
876 			memset(&nd, 0, sizeof(nd));
877 			strlcpy(nd.ifname, ifa->ifa_name, sizeof(nd.ifname));
878 			if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
879 				warnmsg(LOG_ERR, __func__,
880 					"ioctl(SIOCGIFINFO_IN6)");
881 				exit(1);
882 			}
883 			if ((nd.ndi.flags & ND6_IFF_IFDISABLED))
884 				continue;
885 			if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV))
886 				continue;
887 		}
888 
889 		/* if we find multiple candidates, just warn. */
890 		if (n != 0 && dflag > 1)
891 			warnmsg(LOG_WARNING, __func__,
892 				"multiple interfaces found");
893 
894 		a = realloc(argv, (n + 1) * sizeof(char *));
895 		if (a == NULL) {
896 			warnmsg(LOG_ERR, __func__, "realloc");
897 			exit(1);
898 		}
899 		argv = a;
900 		argv[n] = strdup(ifa->ifa_name);
901 		if (!argv[n]) {
902 			warnmsg(LOG_ERR, __func__, "malloc");
903 			exit(1);
904 		}
905 		n++;
906 	}
907 
908 	if (n) {
909 		a = realloc(argv, (n + 1) * sizeof(char *));
910 		if (a == NULL) {
911 			warnmsg(LOG_ERR, __func__, "realloc");
912 			exit(1);
913 		}
914 		argv = a;
915 		argv[n] = NULL;
916 
917 		if (dflag > 0) {
918 			for (i = 0; i < n; i++)
919 				warnmsg(LOG_WARNING, __func__, "probing %s",
920 					argv[i]);
921 		}
922 	}
923 	if (!Fflag)
924 		close(s);
925 	freeifaddrs(ifap);
926 	return (argv);
927 }
928