xref: /freebsd/usr.sbin/rtsold/rtsold.c (revision 4bc52338)
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/param.h>
37 #include <sys/capsicum.h>
38 #include <sys/event.h>
39 #include <sys/ioctl.h>
40 #include <sys/socket.h>
41 
42 #include <net/if.h>
43 #include <net/if_dl.h>
44 
45 #include <netinet/in.h>
46 #include <netinet/icmp6.h>
47 #include <netinet/in_var.h>
48 #include <arpa/inet.h>
49 
50 #include <netinet6/nd6.h>
51 
52 #include <capsicum_helpers.h>
53 #include <err.h>
54 #include <errno.h>
55 #include <ifaddrs.h>
56 #include <libgen.h>
57 #include <signal.h>
58 #include <stdarg.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <syslog.h>
63 #include <time.h>
64 #include <unistd.h>
65 
66 #include <libcasper.h>
67 #include <casper/cap_syslog.h>
68 #include <libutil.h>
69 
70 #include "rtsold.h"
71 
72 #define RTSOL_DUMPFILE	"/var/run/rtsold.dump"
73 
74 struct timespec tm_max;
75 static int log_upto = 999;
76 static int fflag = 0;
77 
78 int Fflag = 0;	/* force setting sysctl parameters */
79 int aflag = 0;
80 int dflag = 0;
81 int uflag = 0;
82 
83 const char *otherconf_script;
84 const char *resolvconf_script = "/sbin/resolvconf";
85 
86 cap_channel_t *capllflags, *capscript, *capsendmsg, *capsyslog;
87 
88 /* protocol constants */
89 #define MAX_RTR_SOLICITATION_DELAY	1 /* second */
90 #define RTR_SOLICITATION_INTERVAL	4 /* seconds */
91 #define MAX_RTR_SOLICITATIONS		3 /* times */
92 
93 /*
94  * implementation dependent constants in seconds
95  * XXX: should be configurable
96  */
97 #define PROBE_INTERVAL 60
98 
99 /* static variables and functions */
100 static int mobile_node = 0;
101 
102 static sig_atomic_t do_dump, do_exit;
103 static struct pidfh *pfh;
104 
105 static char **autoifprobe(void);
106 static int ifconfig(char *ifname);
107 static int init_capabilities(void);
108 static int make_packet(struct ifinfo *);
109 static struct timespec *rtsol_check_timer(void);
110 
111 static void set_dumpfile(int);
112 static void set_exit(int);
113 static void usage(const char *progname);
114 
115 int
116 main(int argc, char **argv)
117 {
118 	struct kevent events[2];
119 	FILE *dumpfp;
120 	struct ifinfo *ifi;
121 	struct timespec *timeout;
122 	const char *opts, *pidfilepath, *progname;
123 	int ch, error, kq, once, rcvsock, rtsock;
124 
125 	progname = basename(argv[0]);
126 	if (strcmp(progname, "rtsold") == 0) {
127 		opts = "adDfFm1O:p:R:u";
128 		once = 0;
129 		pidfilepath = NULL;
130 	} else {
131 		opts = "adDFO:R:u";
132 		fflag = 1;
133 		once = 1;
134 	}
135 
136 	while ((ch = getopt(argc, argv, opts)) != -1) {
137 		switch (ch) {
138 		case 'a':
139 			aflag = 1;
140 			break;
141 		case 'd':
142 			dflag += 1;
143 			break;
144 		case 'D':
145 			dflag += 2;
146 			break;
147 		case 'f':
148 			fflag = 1;
149 			break;
150 		case 'F':
151 			Fflag = 1;
152 			break;
153 		case 'm':
154 			mobile_node = 1;
155 			break;
156 		case '1':
157 			once = 1;
158 			break;
159 		case 'O':
160 			otherconf_script = optarg;
161 			break;
162 		case 'p':
163 			pidfilepath = optarg;
164 			break;
165 		case 'R':
166 			resolvconf_script = optarg;
167 			break;
168 		case 'u':
169 			uflag = 1;
170 			break;
171 		default:
172 			usage(progname);
173 		}
174 	}
175 	argc -= optind;
176 	argv += optind;
177 
178 	if ((!aflag && argc == 0) || (aflag && argc != 0))
179 		usage(progname);
180 
181 	/* Generate maximum time in timespec. */
182 	tm_max.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
183 	tm_max.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
184 
185 	/* set log level */
186 	if (dflag > 1)
187 		log_upto = LOG_DEBUG;
188 	else if (dflag > 0)
189 		log_upto = LOG_INFO;
190 	else
191 		log_upto = LOG_NOTICE;
192 
193 	if (otherconf_script != NULL && *otherconf_script != '/')
194 		errx(1, "configuration script (%s) must be an absolute path",
195 		    otherconf_script);
196 	if (*resolvconf_script != '/')
197 		errx(1, "configuration script (%s) must be an absolute path",
198 		    resolvconf_script);
199 
200 	if (!fflag) {
201 		pfh = pidfile_open(pidfilepath, 0644, NULL);
202 		if (pfh == NULL)
203 			errx(1, "failed to open pidfile: %s", strerror(errno));
204 		if (daemon(0, 0) != 0)
205 			errx(1, "failed to daemonize");
206 	}
207 
208 	if ((error = init_capabilities()) != 0)
209 		err(1, "failed to initialize capabilities");
210 
211 	if (!fflag) {
212 		cap_openlog(capsyslog, progname, LOG_NDELAY | LOG_PID,
213 		    LOG_DAEMON);
214 		if (log_upto >= 0)
215 			(void)cap_setlogmask(capsyslog, LOG_UPTO(log_upto));
216 		(void)signal(SIGTERM, set_exit);
217 		(void)signal(SIGINT, set_exit);
218 		(void)signal(SIGUSR1, set_dumpfile);
219 		dumpfp = rtsold_init_dumpfile(RTSOL_DUMPFILE);
220 	} else
221 		dumpfp = NULL;
222 
223 	kq = kqueue();
224 	if (kq < 0) {
225 		warnmsg(LOG_ERR, __func__, "failed to create a kqueue: %s",
226 		    strerror(errno));
227 		exit(1);
228 	}
229 
230 	/* Open global sockets and register for read events. */
231 	if ((rtsock = rtsock_open()) < 0) {
232 		warnmsg(LOG_ERR, __func__, "failed to open routing socket");
233 		exit(1);
234 	}
235 	if ((rcvsock = recvsockopen()) < 0) {
236 		warnmsg(LOG_ERR, __func__, "failed to open receive socket");
237 		exit(1);
238 	}
239 	EV_SET(&events[0], rtsock, EVFILT_READ, EV_ADD, 0, 0, NULL);
240 	EV_SET(&events[1], rcvsock, EVFILT_READ, EV_ADD, 0, 0, NULL);
241 	if (kevent(kq, events, 2, NULL, 0, NULL) < 0) {
242 		warnmsg(LOG_ERR, __func__, "kevent(): %s", strerror(errno));
243 		exit(1);
244 	}
245 
246 	/* Probe network interfaces and set up tracking info. */
247 	if (ifinit() != 0) {
248 		warnmsg(LOG_ERR, __func__, "failed to initialize interfaces");
249 		exit(1);
250 	}
251 	if (aflag)
252 		argv = autoifprobe();
253 	while (argv && *argv) {
254 		if (ifconfig(*argv)) {
255 			warnmsg(LOG_ERR, __func__,
256 			    "failed to initialize %s", *argv);
257 			exit(1);
258 		}
259 		argv++;
260 	}
261 
262 	/* Write to our pidfile. */
263 	if (pfh != NULL && pidfile_write(pfh) != 0) {
264 		warnmsg(LOG_ERR, __func__,
265 		    "failed to open pidfile: %s", strerror(errno));
266 		exit(1);
267 	}
268 
269 	/* Enter capability mode. */
270 	caph_cache_catpages();
271 	if (caph_enter_casper() != 0) {
272 		warnmsg(LOG_ERR, __func__, "caph_enter(): %s", strerror(errno));
273 		exit(1);
274 	}
275 
276 	for (;;) {
277 		if (do_exit) {
278 			/* Handle SIGTERM, SIGINT. */
279 			if (pfh != NULL)
280 				pidfile_remove(pfh);
281 			break;
282 		}
283 		if (do_dump) {
284 			/* Handle SIGUSR1. */
285 			do_dump = 0;
286 			if (dumpfp != NULL)
287 				rtsold_dump(dumpfp);
288 		}
289 
290 		timeout = rtsol_check_timer();
291 
292 		if (once) {
293 			/* if we have no timeout, we are done (or failed) */
294 			if (timeout == NULL)
295 				break;
296 
297 			/* if all interfaces have got RA packet, we are done */
298 			TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
299 				if (ifi->state != IFS_DOWN && ifi->racnt == 0)
300 					break;
301 			}
302 			if (ifi == NULL)
303 				break;
304 		}
305 
306 		error = kevent(kq, NULL, 0, &events[0], 1, timeout);
307 		if (error < 1) {
308 			if (error < 0 && errno != EINTR)
309 				warnmsg(LOG_ERR, __func__, "kevent(): %s",
310 				    strerror(errno));
311 			continue;
312 		}
313 
314 		if (events[0].ident == (uintptr_t)rtsock)
315 			rtsock_input(rtsock);
316 		else
317 			rtsol_input(rcvsock);
318 	}
319 
320 	return (0);
321 }
322 
323 static int
324 init_capabilities(void)
325 {
326 #ifdef WITH_CASPER
327 	const char *const scripts[2] = { resolvconf_script, otherconf_script };
328 	cap_channel_t *capcasper;
329 	nvlist_t *limits;
330 
331 	capcasper = cap_init();
332 	if (capcasper == NULL)
333 		return (-1);
334 
335 	capllflags = cap_service_open(capcasper, "rtsold.llflags");
336 	if (capllflags == NULL)
337 		return (-1);
338 
339 	capscript = cap_service_open(capcasper, "rtsold.script");
340 	if (capscript == NULL)
341 		return (-1);
342 	limits = nvlist_create(0);
343 	nvlist_add_string_array(limits, "scripts", scripts,
344 	    otherconf_script != NULL ? 2 : 1);
345 	if (cap_limit_set(capscript, limits) != 0)
346 		return (-1);
347 
348 	capsendmsg = cap_service_open(capcasper, "rtsold.sendmsg");
349 	if (capsendmsg == NULL)
350 		return (-1);
351 
352 	if (!fflag) {
353 		capsyslog = cap_service_open(capcasper, "system.syslog");
354 		if (capsyslog == NULL)
355 			return (-1);
356 	}
357 
358 	cap_close(capcasper);
359 #endif /* WITH_CASPER */
360 	return (0);
361 }
362 
363 static int
364 ifconfig(char *ifname)
365 {
366 	struct ifinfo *ifi;
367 	struct sockaddr_dl *sdl;
368 	int flags;
369 
370 	ifi = NULL;
371 	if ((sdl = if_nametosdl(ifname)) == NULL) {
372 		warnmsg(LOG_ERR, __func__,
373 		    "failed to get link layer information for %s", ifname);
374 		goto bad;
375 	}
376 	if (find_ifinfo(sdl->sdl_index)) {
377 		warnmsg(LOG_ERR, __func__,
378 		    "interface %s was already configured", ifname);
379 		goto bad;
380 	}
381 
382 	if (Fflag) {
383 		struct in6_ndireq nd;
384 		int s;
385 
386 		if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
387 			warnmsg(LOG_ERR, __func__, "socket() failed.");
388 			goto bad;
389 		}
390 		memset(&nd, 0, sizeof(nd));
391 		strlcpy(nd.ifname, ifname, sizeof(nd.ifname));
392 		if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
393 			warnmsg(LOG_ERR, __func__,
394 			    "cannot get accept_rtadv flag");
395 			(void)close(s);
396 			goto bad;
397 		}
398 		nd.ndi.flags |= ND6_IFF_ACCEPT_RTADV;
399 		if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd) < 0) {
400 			warnmsg(LOG_ERR, __func__,
401 			    "cannot set accept_rtadv flag");
402 			(void)close(s);
403 			goto bad;
404 		}
405 		(void)close(s);
406 	}
407 
408 	if ((ifi = malloc(sizeof(*ifi))) == NULL) {
409 		warnmsg(LOG_ERR, __func__, "memory allocation failed");
410 		goto bad;
411 	}
412 	memset(ifi, 0, sizeof(*ifi));
413 	ifi->sdl = sdl;
414 	ifi->ifi_rdnss = IFI_DNSOPT_STATE_NOINFO;
415 	ifi->ifi_dnssl = IFI_DNSOPT_STATE_NOINFO;
416 	TAILQ_INIT(&ifi->ifi_rainfo);
417 	strlcpy(ifi->ifname, ifname, sizeof(ifi->ifname));
418 
419 	/* construct a router solicitation message */
420 	if (make_packet(ifi))
421 		goto bad;
422 
423 	/* set link ID of this interface. */
424 #ifdef HAVE_SCOPELIB
425 	if (inet_zoneid(AF_INET6, 2, ifname, &ifi->linkid))
426 		goto bad;
427 #else
428 	/* XXX: assume interface IDs as link IDs */
429 	ifi->linkid = ifi->sdl->sdl_index;
430 #endif
431 
432 	/*
433 	 * check if the interface is available.
434 	 * also check if SIOCGIFMEDIA ioctl is OK on the interface.
435 	 */
436 	ifi->mediareqok = 1;
437 	ifi->active = interface_status(ifi);
438 	if (!ifi->mediareqok) {
439 		/*
440 		 * probe routers periodically even if the link status
441 		 * does not change.
442 		 */
443 		ifi->probeinterval = PROBE_INTERVAL;
444 	}
445 
446 	/* activate interface: interface_up returns 0 on success */
447 	flags = interface_up(ifi->ifname);
448 	if (flags == 0)
449 		ifi->state = IFS_DELAY;
450 	else if (flags == IFS_TENTATIVE)
451 		ifi->state = IFS_TENTATIVE;
452 	else
453 		ifi->state = IFS_DOWN;
454 
455 	rtsol_timer_update(ifi);
456 
457 	TAILQ_INSERT_TAIL(&ifinfo_head, ifi, ifi_next);
458 	return (0);
459 
460 bad:
461 	free(sdl);
462 	free(ifi);
463 	return (-1);
464 }
465 
466 struct rainfo *
467 find_rainfo(struct ifinfo *ifi, struct sockaddr_in6 *sin6)
468 {
469 	struct rainfo *rai;
470 
471 	TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next)
472 		if (memcmp(&rai->rai_saddr.sin6_addr, &sin6->sin6_addr,
473 		    sizeof(rai->rai_saddr.sin6_addr)) == 0)
474 			return (rai);
475 
476 	return (NULL);
477 }
478 
479 struct ifinfo *
480 find_ifinfo(int ifindex)
481 {
482 	struct ifinfo *ifi;
483 
484 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
485 		if (ifi->sdl->sdl_index == ifindex)
486 			return (ifi);
487 	}
488 	return (NULL);
489 }
490 
491 static int
492 make_packet(struct ifinfo *ifi)
493 {
494 	size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
495 	struct nd_router_solicit *rs;
496 	char *buf;
497 
498 	if ((lladdroptlen = lladdropt_length(ifi->sdl)) == 0) {
499 		warnmsg(LOG_INFO, __func__,
500 		    "link-layer address option has null length"
501 		    " on %s. Treat as not included.", ifi->ifname);
502 	}
503 	packlen += lladdroptlen;
504 	ifi->rs_datalen = packlen;
505 
506 	/* allocate buffer */
507 	if ((buf = malloc(packlen)) == NULL) {
508 		warnmsg(LOG_ERR, __func__,
509 		    "memory allocation failed for %s", ifi->ifname);
510 		return (-1);
511 	}
512 	ifi->rs_data = buf;
513 
514 	/* fill in the message */
515 	rs = (struct nd_router_solicit *)buf;
516 	rs->nd_rs_type = ND_ROUTER_SOLICIT;
517 	rs->nd_rs_code = 0;
518 	rs->nd_rs_cksum = 0;
519 	rs->nd_rs_reserved = 0;
520 	buf += sizeof(*rs);
521 
522 	/* fill in source link-layer address option */
523 	if (lladdroptlen)
524 		lladdropt_fill(ifi->sdl, (struct nd_opt_hdr *)buf);
525 
526 	return (0);
527 }
528 
529 static struct timespec *
530 rtsol_check_timer(void)
531 {
532 	static struct timespec returnval;
533 	struct timespec now, rtsol_timer;
534 	struct ifinfo *ifi;
535 	struct rainfo *rai;
536 	struct ra_opt *rao, *raotmp;
537 	int error, flags;
538 
539 	clock_gettime(CLOCK_MONOTONIC_FAST, &now);
540 
541 	rtsol_timer = tm_max;
542 
543 	TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
544 		if (TS_CMP(&ifi->expire, &now, <=)) {
545 			warnmsg(LOG_DEBUG, __func__, "timer expiration on %s, "
546 			    "state = %d", ifi->ifname, ifi->state);
547 
548 			while((rai = TAILQ_FIRST(&ifi->ifi_rainfo)) != NULL) {
549 				/* Remove all RA options. */
550 				TAILQ_REMOVE(&ifi->ifi_rainfo, rai, rai_next);
551 				while ((rao = TAILQ_FIRST(&rai->rai_ra_opt)) !=
552 				    NULL) {
553 					TAILQ_REMOVE(&rai->rai_ra_opt, rao,
554 					    rao_next);
555 					if (rao->rao_msg != NULL)
556 						free(rao->rao_msg);
557 					free(rao);
558 				}
559 				free(rai);
560 			}
561 			switch (ifi->state) {
562 			case IFS_DOWN:
563 			case IFS_TENTATIVE:
564 				/* interface_up returns 0 on success */
565 				flags = interface_up(ifi->ifname);
566 				if (flags == 0)
567 					ifi->state = IFS_DELAY;
568 				else if (flags == IFS_TENTATIVE)
569 					ifi->state = IFS_TENTATIVE;
570 				else
571 					ifi->state = IFS_DOWN;
572 				break;
573 			case IFS_IDLE:
574 			{
575 				int oldstatus = ifi->active;
576 				int probe = 0;
577 
578 				ifi->active = interface_status(ifi);
579 
580 				if (oldstatus != ifi->active) {
581 					warnmsg(LOG_DEBUG, __func__,
582 					    "%s status is changed"
583 					    " from %d to %d",
584 					    ifi->ifname,
585 					    oldstatus, ifi->active);
586 					probe = 1;
587 					ifi->state = IFS_DELAY;
588 				} else if (ifi->probeinterval &&
589 				    (ifi->probetimer -=
590 				    ifi->timer.tv_sec) <= 0) {
591 					/* probe timer expired */
592 					ifi->probetimer =
593 					    ifi->probeinterval;
594 					probe = 1;
595 					ifi->state = IFS_PROBE;
596 				}
597 
598 				/*
599 				 * If we need a probe, clear the previous
600 				 * status wrt the "other" configuration.
601 				 */
602 				if (probe)
603 					ifi->otherconfig = 0;
604 				if (probe && mobile_node) {
605 					error = cap_probe_defrouters(capsendmsg,
606 					    ifi);
607 					if (error != 0)
608 						warnmsg(LOG_DEBUG, __func__,
609 					    "failed to probe routers: %d",
610 						    error);
611 				}
612 				break;
613 			}
614 			case IFS_DELAY:
615 				ifi->state = IFS_PROBE;
616 				(void)cap_rssend(capsendmsg, ifi);
617 				break;
618 			case IFS_PROBE:
619 				if (ifi->probes < MAX_RTR_SOLICITATIONS)
620 					(void)cap_rssend(capsendmsg, ifi);
621 				else {
622 					warnmsg(LOG_INFO, __func__,
623 					    "No answer after sending %d RSs",
624 					    ifi->probes);
625 					ifi->probes = 0;
626 					ifi->state = IFS_IDLE;
627 				}
628 				break;
629 			}
630 			rtsol_timer_update(ifi);
631 		} else {
632 			/* Expiration check for RA options. */
633 			int expire = 0;
634 
635 			TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next) {
636 				TAILQ_FOREACH_SAFE(rao, &rai->rai_ra_opt,
637 				    rao_next, raotmp) {
638 					warnmsg(LOG_DEBUG, __func__,
639 					    "RA expiration timer: "
640 					    "type=%d, msg=%s, expire=%s",
641 					    rao->rao_type, (char *)rao->rao_msg,
642 						sec2str(&rao->rao_expire));
643 					if (TS_CMP(&now, &rao->rao_expire,
644 					    >=)) {
645 						warnmsg(LOG_DEBUG, __func__,
646 						    "RA expiration timer: "
647 						    "expired.");
648 						TAILQ_REMOVE(&rai->rai_ra_opt,
649 						    rao, rao_next);
650 						if (rao->rao_msg != NULL)
651 							free(rao->rao_msg);
652 						free(rao);
653 						expire = 1;
654 					}
655 				}
656 			}
657 			if (expire)
658 				ra_opt_handler(ifi);
659 		}
660 		if (TS_CMP(&ifi->expire, &rtsol_timer, <))
661 			rtsol_timer = ifi->expire;
662 	}
663 
664 	if (TS_CMP(&rtsol_timer, &tm_max, ==)) {
665 		warnmsg(LOG_DEBUG, __func__, "there is no timer");
666 		return (NULL);
667 	} else if (TS_CMP(&rtsol_timer, &now, <))
668 		/* this may occur when the interval is too small */
669 		returnval.tv_sec = returnval.tv_nsec = 0;
670 	else
671 		TS_SUB(&rtsol_timer, &now, &returnval);
672 
673 	now.tv_sec += returnval.tv_sec;
674 	now.tv_nsec += returnval.tv_nsec;
675 	warnmsg(LOG_DEBUG, __func__, "New timer is %s",
676 	    sec2str(&now));
677 
678 	return (&returnval);
679 }
680 
681 void
682 rtsol_timer_update(struct ifinfo *ifi)
683 {
684 #define MILLION 1000000
685 #define DADRETRY 10		/* XXX: adhoc */
686 	long interval;
687 	struct timespec now;
688 
689 	bzero(&ifi->timer, sizeof(ifi->timer));
690 
691 	switch (ifi->state) {
692 	case IFS_DOWN:
693 	case IFS_TENTATIVE:
694 		if (++ifi->dadcount > DADRETRY) {
695 			ifi->dadcount = 0;
696 			ifi->timer.tv_sec = PROBE_INTERVAL;
697 		} else
698 			ifi->timer.tv_sec = 1;
699 		break;
700 	case IFS_IDLE:
701 		if (mobile_node)
702 			/* XXX should be configurable */
703 			ifi->timer.tv_sec = 3;
704 		else
705 			ifi->timer = tm_max;	/* stop timer(valid?) */
706 		break;
707 	case IFS_DELAY:
708 		interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
709 		ifi->timer.tv_sec = interval / MILLION;
710 		ifi->timer.tv_nsec = (interval % MILLION) * 1000;
711 		break;
712 	case IFS_PROBE:
713 		if (ifi->probes < MAX_RTR_SOLICITATIONS)
714 			ifi->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
715 		else
716 			/*
717 			 * After sending MAX_RTR_SOLICITATIONS solicitations,
718 			 * we're just waiting for possible replies; there
719 			 * will be no more solicitation.  Thus, we change
720 			 * the timer value to MAX_RTR_SOLICITATION_DELAY based
721 			 * on RFC 2461, Section 6.3.7.
722 			 */
723 			ifi->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
724 		break;
725 	default:
726 		warnmsg(LOG_ERR, __func__,
727 		    "illegal interface state(%d) on %s",
728 		    ifi->state, ifi->ifname);
729 		return;
730 	}
731 
732 	/* reset the timer */
733 	if (TS_CMP(&ifi->timer, &tm_max, ==)) {
734 		ifi->expire = tm_max;
735 		warnmsg(LOG_DEBUG, __func__,
736 		    "stop timer for %s", ifi->ifname);
737 	} else {
738 		clock_gettime(CLOCK_MONOTONIC_FAST, &now);
739 		TS_ADD(&now, &ifi->timer, &ifi->expire);
740 
741 		now.tv_sec += ifi->timer.tv_sec;
742 		now.tv_nsec += ifi->timer.tv_nsec;
743 		warnmsg(LOG_DEBUG, __func__, "set timer for %s to %s",
744 		    ifi->ifname, sec2str(&now));
745 	}
746 
747 #undef MILLION
748 }
749 
750 static void
751 set_dumpfile(int sig __unused)
752 {
753 
754 	do_dump = 1;
755 }
756 
757 static void
758 set_exit(int sig __unused)
759 {
760 
761 	do_exit = 1;
762 }
763 
764 static void
765 usage(const char *progname)
766 {
767 
768 	if (strcmp(progname, "rtsold") == 0) {
769 		fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
770 		    "[-p pidfile] [-R script-name] interface ...\n");
771 		fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
772 		    "[-p pidfile] [-R script-name] -a\n");
773 	} else {
774 		fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
775 		    "[-p pidfile] [-R script-name] interface ...\n");
776 		fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
777 		    "[-p pidfile] [-R script-name] -a\n");
778 	}
779 	exit(1);
780 }
781 
782 void
783 warnmsg(int priority, const char *func, const char *msg, ...)
784 {
785 	va_list ap;
786 	char buf[BUFSIZ];
787 
788 	va_start(ap, msg);
789 	if (fflag) {
790 		if (priority <= log_upto)
791 			vwarnx(msg, ap);
792 	} else {
793 		snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
794 		msg = buf;
795 		cap_vsyslog(capsyslog, priority, msg, ap);
796 	}
797 	va_end(ap);
798 }
799 
800 /*
801  * return a list of interfaces which is suitable to sending an RS.
802  */
803 static char **
804 autoifprobe(void)
805 {
806 	static char **argv = NULL;
807 	static int n = 0;
808 	char **a;
809 	int s = 0, i, found;
810 	struct ifaddrs *ifap, *ifa;
811 	struct in6_ndireq nd;
812 
813 	/* initialize */
814 	while (n--)
815 		free(argv[n]);
816 	if (argv) {
817 		free(argv);
818 		argv = NULL;
819 	}
820 	n = 0;
821 
822 	if (getifaddrs(&ifap) != 0)
823 		return (NULL);
824 
825 	if (!Fflag && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
826 		warnmsg(LOG_ERR, __func__, "socket");
827 		exit(1);
828 	}
829 
830 	/* find an ethernet */
831 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
832 		if ((ifa->ifa_flags & IFF_UP) == 0)
833 			continue;
834 		if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
835 			continue;
836 		if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
837 			continue;
838 		if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
839 			continue;
840 
841 		if (ifa->ifa_addr->sa_family != AF_INET6)
842 			continue;
843 
844 		found = 0;
845 		for (i = 0; i < n; i++) {
846 			if (strcmp(argv[i], ifa->ifa_name) == 0) {
847 				found++;
848 				break;
849 			}
850 		}
851 		if (found)
852 			continue;
853 
854 		/*
855 		 * Skip the interfaces which IPv6 and/or accepting RA
856 		 * is disabled.
857 		 */
858 		if (!Fflag) {
859 			memset(&nd, 0, sizeof(nd));
860 			strlcpy(nd.ifname, ifa->ifa_name, sizeof(nd.ifname));
861 			if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
862 				warnmsg(LOG_ERR, __func__,
863 					"ioctl(SIOCGIFINFO_IN6)");
864 				exit(1);
865 			}
866 			if ((nd.ndi.flags & ND6_IFF_IFDISABLED))
867 				continue;
868 			if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV))
869 				continue;
870 		}
871 
872 		/* if we find multiple candidates, just warn. */
873 		if (n != 0 && dflag > 1)
874 			warnmsg(LOG_WARNING, __func__,
875 				"multiple interfaces found");
876 
877 		a = realloc(argv, (n + 1) * sizeof(char *));
878 		if (a == NULL) {
879 			warnmsg(LOG_ERR, __func__, "realloc");
880 			exit(1);
881 		}
882 		argv = a;
883 		argv[n] = strdup(ifa->ifa_name);
884 		if (!argv[n]) {
885 			warnmsg(LOG_ERR, __func__, "malloc");
886 			exit(1);
887 		}
888 		n++;
889 	}
890 
891 	if (n) {
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] = NULL;
899 
900 		if (dflag > 0) {
901 			for (i = 0; i < n; i++)
902 				warnmsg(LOG_WARNING, __func__, "probing %s",
903 					argv[i]);
904 		}
905 	}
906 	if (!Fflag)
907 		close(s);
908 	freeifaddrs(ifap);
909 	return (argv);
910 }
911