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
67struct timespec tm_max;
68static int log_upto = 999;
69static int fflag = 0;
70
71int Fflag = 0;	/* force setting sysctl parameters */
72int aflag = 0;
73int dflag = 0;
74int uflag = 0;
75
76const char *otherconf_script;
77const 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 */
91static int mobile_node = 0;
92static const char *pidfilename = RTSOL_PIDFILE;
93
94#ifndef SMALL
95static int do_dump;
96static const char *dumpfilename = RTSOL_DUMPFILE;
97#endif
98
99#if 0
100static int ifreconfig(char *);
101#endif
102
103static int make_packet(struct ifinfo *);
104static struct timespec *rtsol_check_timer(void);
105
106#ifndef SMALL
107static void rtsold_set_dump_file(int);
108#endif
109static void usage(void);
110
111int
112main(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
341int
342ifconfig(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
439bad:
440	free(ifi->sdl);
441	free(ifi);
442	return (-1);
443}
444
445void
446iflist_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
461static int
462ifreconfig(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
487struct rainfo *
488find_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
500struct ifinfo *
501find_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
512static int
513make_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
550static struct timespec *
551rtsol_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
697void
698rtsol_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
772static void
773rtsold_set_dump_file(int sig __unused)
774{
775	do_dump = 1;
776}
777#endif
778
779static void
780usage(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
795void
796warnmsg(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 */
818char **
819autoifprobe(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