xref: /freebsd/usr.sbin/rtadvd/rtadvd.c (revision f9218d3d4fd34f082473b3a021c6d4d109fb47cf)
1 /*	$FreeBSD$	*/
2 /*	$KAME: rtadvd.c,v 1.50 2001/02/04 06:15:15 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/param.h>
34 #include <sys/socket.h>
35 #include <sys/uio.h>
36 #include <sys/time.h>
37 #include <sys/queue.h>
38 
39 #include <net/if.h>
40 #include <net/route.h>
41 #include <net/if_dl.h>
42 #include <netinet/in.h>
43 #include <netinet/ip6.h>
44 #include <netinet6/ip6_var.h>
45 #include <netinet/icmp6.h>
46 
47 #include <arpa/inet.h>
48 
49 #include <time.h>
50 #include <unistd.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <err.h>
54 #include <errno.h>
55 #include <string.h>
56 #include <stdlib.h>
57 #include <syslog.h>
58 #include "rtadvd.h"
59 #include "rrenum.h"
60 #include "advcap.h"
61 #include "timer.h"
62 #include "if.h"
63 #include "config.h"
64 #include "dump.h"
65 
66 struct msghdr rcvmhdr;
67 static u_char *rcvcmsgbuf;
68 static size_t rcvcmsgbuflen;
69 static u_char *sndcmsgbuf = NULL;
70 static size_t sndcmsgbuflen;
71 static int do_dump;
72 static int do_die;
73 struct msghdr sndmhdr;
74 struct iovec rcviov[2];
75 struct iovec sndiov[2];
76 struct sockaddr_in6 from;
77 struct sockaddr_in6 sin6_allnodes = {sizeof(sin6_allnodes), AF_INET6};
78 struct in6_addr in6a_site_allrouters;
79 static char *dumpfilename = "/var/run/rtadvd.dump"; /* XXX: should be configurable */
80 static char *pidfilename = "/var/run/rtadvd.pid"; /* should be configurable */
81 static char *mcastif;
82 int sock;
83 int rtsock = -1;
84 #ifdef MIP6
85 int mobileip6 = 0;
86 #endif
87 int accept_rr = 0;
88 int dflag = 0, sflag = 0;
89 
90 u_char *conffile = NULL;
91 
92 struct rainfo *ralist = NULL;
93 struct nd_optlist {
94 	struct nd_optlist *next;
95 	struct nd_opt_hdr *opt;
96 };
97 union nd_opts {
98 	struct nd_opt_hdr *nd_opt_array[7];
99 	struct {
100 		struct nd_opt_hdr *zero;
101 		struct nd_opt_hdr *src_lladdr;
102 		struct nd_opt_hdr *tgt_lladdr;
103 		struct nd_opt_prefix_info *pi;
104 		struct nd_opt_rd_hdr *rh;
105 		struct nd_opt_mtu *mtu;
106 		struct nd_optlist *list;
107 	} nd_opt_each;
108 };
109 #define nd_opts_src_lladdr	nd_opt_each.src_lladdr
110 #define nd_opts_tgt_lladdr	nd_opt_each.tgt_lladdr
111 #define nd_opts_pi		nd_opt_each.pi
112 #define nd_opts_rh		nd_opt_each.rh
113 #define nd_opts_mtu		nd_opt_each.mtu
114 #define nd_opts_list		nd_opt_each.list
115 
116 #define NDOPT_FLAG_SRCLINKADDR 0x1
117 #define NDOPT_FLAG_TGTLINKADDR 0x2
118 #define NDOPT_FLAG_PREFIXINFO 0x4
119 #define NDOPT_FLAG_RDHDR 0x8
120 #define NDOPT_FLAG_MTU 0x10
121 
122 u_int32_t ndopt_flags[] = {
123 	0, NDOPT_FLAG_SRCLINKADDR, NDOPT_FLAG_TGTLINKADDR,
124 	NDOPT_FLAG_PREFIXINFO, NDOPT_FLAG_RDHDR, NDOPT_FLAG_MTU
125 };
126 
127 int main __P((int, char *[]));
128 static void set_die __P((int));
129 static void die __P((void));
130 static void sock_open __P((void));
131 static void rtsock_open __P((void));
132 static void rtadvd_input __P((void));
133 static void rs_input __P((int, struct nd_router_solicit *,
134 			  struct in6_pktinfo *, struct sockaddr_in6 *));
135 static void ra_input __P((int, struct nd_router_advert *,
136 			  struct in6_pktinfo *, struct sockaddr_in6 *));
137 static int prefix_check __P((struct nd_opt_prefix_info *, struct rainfo *,
138 			     struct sockaddr_in6 *));
139 static int nd6_options __P((struct nd_opt_hdr *, int,
140 			    union nd_opts *, u_int32_t));
141 static void free_ndopts __P((union nd_opts *));
142 static void ra_output __P((struct rainfo *));
143 static void rtmsg_input __P((void));
144 static void rtadvd_set_dump_file __P((void));
145 
146 int
147 main(argc, argv)
148 	int argc;
149 	char *argv[];
150 {
151 	fd_set fdset;
152 	int maxfd = 0;
153 	struct timeval *timeout;
154 	int i, ch;
155 	int fflag = 0;
156 	FILE *pidfp;
157 	pid_t pid;
158 
159 	openlog("rtadvd", LOG_NDELAY|LOG_PID, LOG_DAEMON);
160 
161 	/* get command line options and arguments */
162 #ifdef MIP6
163 #define OPTIONS "c:dDfM:mRs"
164 #else
165 #define OPTIONS "c:dDfM:Rs"
166 #endif
167 	while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
168 #undef OPTIONS
169 		switch (ch) {
170 		case 'c':
171 			conffile = optarg;
172 			break;
173 		case 'd':
174 			dflag = 1;
175 			break;
176 		case 'D':
177 			dflag = 2;
178 			break;
179 		case 'f':
180 			fflag = 1;
181 			break;
182 		case 'M':
183 			mcastif = optarg;
184 			break;
185 #ifdef MIP6
186 		case 'm':
187 			mobileip6 = 1;
188 			break;
189 #endif
190 		case 'R':
191 			fprintf(stderr, "rtadvd: "
192 				"the -R option is currently ignored.\n");
193 			/* accept_rr = 1; */
194 			/* run anyway... */
195 			break;
196 		case 's':
197 			sflag = 1;
198 			break;
199 		}
200 	}
201 	argc -= optind;
202 	argv += optind;
203 	if (argc == 0) {
204 		fprintf(stderr,
205 #ifdef MIP6
206 			"usage: rtadvd [-dDfMmRs] [-c conffile] "
207 #else
208 			"usage: rtadvd [-dDfMRs] [-c conffile] "
209 #endif
210 			"interfaces...\n");
211 		exit(1);
212 	}
213 
214 	/* set log level */
215 	if (dflag == 0)
216 		(void)setlogmask(LOG_UPTO(LOG_ERR));
217 	if (dflag == 1)
218 		(void)setlogmask(LOG_UPTO(LOG_INFO));
219 
220 	/* timer initialization */
221 	rtadvd_timer_init();
222 
223 	/* random value initialization */
224 #ifdef __FreeBSD__
225 	srandomdev();
226 #else
227 	srandom((u_long)time(NULL));
228 #endif
229 
230 	/* get iflist block from kernel */
231 	init_iflist();
232 
233 	while (argc--)
234 		getconfig(*argv++);
235 
236 	if (inet_pton(AF_INET6, ALLNODES, &sin6_allnodes.sin6_addr) != 1) {
237 		fprintf(stderr, "fatal: inet_pton failed\n");
238 		exit(1);
239 	}
240 	sock_open();
241 
242 	if (!fflag)
243 		daemon(1, 0);
244 
245 	/* record the current PID */
246 	pid = getpid();
247 	if ((pidfp = fopen(pidfilename, "w")) == NULL) {
248 		syslog(LOG_ERR,
249 		    "<%s> failed to open a log file(%s), run anyway.",
250 		    __FUNCTION__, pidfilename);
251 	} else {
252 		fprintf(pidfp, "%d\n", pid);
253 		fclose(pidfp);
254 	}
255 
256 	FD_ZERO(&fdset);
257 	FD_SET(sock, &fdset);
258 	maxfd = sock;
259 	if (sflag == 0) {
260 		rtsock_open();
261 		FD_SET(rtsock, &fdset);
262 		if (rtsock > sock)
263 			maxfd = rtsock;
264 	} else
265 		rtsock = -1;
266 
267 	signal(SIGTERM, (void *)set_die);
268 	signal(SIGUSR1, (void *)rtadvd_set_dump_file);
269 
270 	while (1) {
271 		struct fd_set select_fd = fdset; /* reinitialize */
272 
273 		if (do_dump) {	/* SIGUSR1 */
274 			do_dump = 0;
275 			rtadvd_dump_file(dumpfilename);
276 		}
277 
278 		if (do_die) {
279 			die();
280 			/*NOTREACHED*/
281 		}
282 
283 		/* timer expiration check and reset the timer */
284 		timeout = rtadvd_check_timer();
285 
286 		if (timeout != NULL) {
287 			syslog(LOG_DEBUG,
288 			    "<%s> set timer to %ld:%ld. waiting for "
289 			    "inputs or timeout", __FUNCTION__,
290 			    (long int)timeout->tv_sec,
291 			    (long int)timeout->tv_usec);
292 		} else {
293 			syslog(LOG_DEBUG,
294 			    "<%s> there's no timer. waiting for inputs",
295 			    __FUNCTION__);
296 		}
297 
298 		if ((i = select(maxfd + 1, &select_fd,
299 				NULL, NULL, timeout)) < 0) {
300 			/* EINTR would occur upon SIGUSR1 for status dump */
301 			if (errno != EINTR)
302 				syslog(LOG_ERR, "<%s> select: %s",
303 				    __FUNCTION__, strerror(errno));
304 			continue;
305 		}
306 		if (i == 0)	/* timeout */
307 			continue;
308 		if (rtsock != -1 && FD_ISSET(rtsock, &select_fd))
309 			rtmsg_input();
310 		if (FD_ISSET(sock, &select_fd))
311 			rtadvd_input();
312 	}
313 	exit(0);		/* NOTREACHED */
314 }
315 
316 static void
317 rtadvd_set_dump_file()
318 {
319 	do_dump = 1;
320 }
321 
322 static void
323 set_die(sig)
324 	int sig;
325 {
326 	do_die = 1;
327 }
328 
329 static void
330 die()
331 {
332 	struct rainfo *ra;
333 	int i;
334 	const int retrans = MAX_FINAL_RTR_ADVERTISEMENTS;
335 
336 	if (dflag > 1) {
337 		syslog(LOG_DEBUG, "<%s> cease to be an advertising router\n",
338 		    __FUNCTION__);
339 	}
340 
341 	for (ra = ralist; ra; ra = ra->next) {
342 		ra->lifetime = 0;
343 		make_packet(ra);
344 	}
345 	for (i = 0; i < retrans; i++) {
346 		for (ra = ralist; ra; ra = ra->next)
347 			ra_output(ra);
348 		sleep(MIN_DELAY_BETWEEN_RAS);
349 	}
350 	exit(0);
351 	/*NOTREACHED*/
352 }
353 
354 static void
355 rtmsg_input()
356 {
357 	int n, type, ifindex = 0, plen;
358 	size_t len;
359 	char msg[2048], *next, *lim;
360 	u_char ifname[IF_NAMESIZE];
361 	struct prefix *prefix;
362 	struct rainfo *rai;
363 	struct in6_addr *addr;
364 	char addrbuf[INET6_ADDRSTRLEN];
365 
366 	n = read(rtsock, msg, sizeof(msg));
367 	if (dflag > 1) {
368 		syslog(LOG_DEBUG, "<%s> received a routing message "
369 		    "(type = %d, len = %d)", __FUNCTION__, rtmsg_type(msg), n);
370 	}
371 	if (n > rtmsg_len(msg)) {
372 		/*
373 		 * This usually won't happen for messages received on
374 		 * a routing socket.
375 		 */
376 		if (dflag > 1)
377 			syslog(LOG_DEBUG,
378 			    "<%s> received data length is larger than "
379 			    "1st routing message len. multiple messages? "
380 			    "read %d bytes, but 1st msg len = %d",
381 			    __FUNCTION__, n, rtmsg_len(msg));
382 #if 0
383 		/* adjust length */
384 		n = rtmsg_len(msg);
385 #endif
386 	}
387 
388 	lim = msg + n;
389 	for (next = msg; next < lim; next += len) {
390 		int oldifflags;
391 
392 		next = get_next_msg(next, lim, 0, &len,
393 				    RTADV_TYPE2BITMASK(RTM_ADD) |
394 				    RTADV_TYPE2BITMASK(RTM_DELETE) |
395 				    RTADV_TYPE2BITMASK(RTM_NEWADDR) |
396 				    RTADV_TYPE2BITMASK(RTM_DELADDR) |
397 				    RTADV_TYPE2BITMASK(RTM_IFINFO));
398 		if (len == 0)
399 			break;
400 		type = rtmsg_type(next);
401 		switch (type) {
402 		case RTM_ADD:
403 		case RTM_DELETE:
404 			ifindex = get_rtm_ifindex(next);
405 			break;
406 		case RTM_NEWADDR:
407 		case RTM_DELADDR:
408 			ifindex = get_ifam_ifindex(next);
409 			break;
410 		case RTM_IFINFO:
411 			ifindex = get_ifm_ifindex(next);
412 			break;
413 		default:
414 			/* should not reach here */
415 			if (dflag > 1) {
416 				syslog(LOG_DEBUG,
417 				       "<%s:%d> unknown rtmsg %d on %s",
418 				       __FUNCTION__, __LINE__, type,
419 				       if_indextoname(ifindex, ifname));
420 			}
421 			continue;
422 		}
423 
424 		if ((rai = if_indextorainfo(ifindex)) == NULL) {
425 			if (dflag > 1) {
426 				syslog(LOG_DEBUG,
427 				       "<%s> route changed on "
428 				       "non advertising interface(%s)",
429 				       __FUNCTION__,
430 				       if_indextoname(ifindex, ifname));
431 			}
432 			continue;
433 		}
434 		oldifflags = iflist[ifindex]->ifm_flags;
435 
436 		switch (type) {
437 		case RTM_ADD:
438 			/* init ifflags because it may have changed */
439 			iflist[ifindex]->ifm_flags =
440 			    if_getflags(ifindex, iflist[ifindex]->ifm_flags);
441 
442 			if (sflag)
443 				break;	/* we aren't interested in prefixes  */
444 
445 			addr = get_addr(msg);
446 			plen = get_prefixlen(msg);
447 			/* sanity check for plen */
448 			/* as RFC2373, prefixlen is at least 4 */
449 			if (plen < 4 || plen > 127) {
450 				syslog(LOG_INFO, "<%s> new interface route's"
451 				    "plen %d is invalid for a prefix",
452 				    __FUNCTION__, plen);
453 				break;
454 			}
455 			prefix = find_prefix(rai, addr, plen);
456 			if (prefix) {
457 				if (prefix->timer) {
458 					/*
459 					 * If the prefix has been invalidated,
460 					 * make it available again.
461 					 */
462 					update_prefix(prefix);
463 				} else if (dflag > 1) {
464 					syslog(LOG_DEBUG,
465 					    "<%s> new prefix(%s/%d) "
466 					    "added on %s, "
467 					    "but it was already in list",
468 					    __FUNCTION__,
469 					    inet_ntop(AF_INET6, addr,
470 					    (char *)addrbuf, INET6_ADDRSTRLEN),
471 					    plen, rai->ifname);
472 				}
473 				break;
474 			}
475 			make_prefix(rai, ifindex, addr, plen);
476 			break;
477 		case RTM_DELETE:
478 			/* init ifflags because it may have changed */
479 			iflist[ifindex]->ifm_flags =
480 			    if_getflags(ifindex, iflist[ifindex]->ifm_flags);
481 
482 			if (sflag)
483 				break;
484 
485 			addr = get_addr(msg);
486 			plen = get_prefixlen(msg);
487 			/* sanity check for plen */
488 			/* as RFC2373, prefixlen is at least 4 */
489 			if (plen < 4 || plen > 127) {
490 				syslog(LOG_INFO,
491 				    "<%s> deleted interface route's "
492 				    "plen %d is invalid for a prefix",
493 				    __FUNCTION__, plen);
494 				break;
495 			}
496 			prefix = find_prefix(rai, addr, plen);
497 			if (prefix == NULL) {
498 				if (dflag > 1) {
499 					syslog(LOG_DEBUG,
500 					    "<%s> prefix(%s/%d) was "
501 					    "deleted on %s, "
502 					    "but it was not in list",
503 					    __FUNCTION__,
504 					    inet_ntop(AF_INET6, addr,
505 					    (char *)addrbuf, INET6_ADDRSTRLEN),
506 					    plen, rai->ifname);
507 				}
508 				break;
509 			}
510 			invalidate_prefix(prefix);
511 			break;
512 		case RTM_NEWADDR:
513 		case RTM_DELADDR:
514 			/* init ifflags because it may have changed */
515 			iflist[ifindex]->ifm_flags =
516 			    if_getflags(ifindex, iflist[ifindex]->ifm_flags);
517 			break;
518 		case RTM_IFINFO:
519 			iflist[ifindex]->ifm_flags = get_ifm_flags(next);
520 			break;
521 		default:
522 			/* should not reach here */
523 			if (dflag > 1) {
524 				syslog(LOG_DEBUG,
525 				    "<%s:%d> unknown rtmsg %d on %s",
526 				    __FUNCTION__, __LINE__, type,
527 				    if_indextoname(ifindex, ifname));
528 			}
529 			return;
530 		}
531 
532 		/* check if an interface flag is changed */
533 		if ((oldifflags & IFF_UP) != 0 &&	/* UP to DOWN */
534 		    (iflist[ifindex]->ifm_flags & IFF_UP) == 0) {
535 			syslog(LOG_INFO,
536 			    "<%s> interface %s becomes down. stop timer.",
537 			    __FUNCTION__, rai->ifname);
538 			rtadvd_remove_timer(&rai->timer);
539 		} else if ((oldifflags & IFF_UP) == 0 &&	/* DOWN to UP */
540 			 (iflist[ifindex]->ifm_flags & IFF_UP) != 0) {
541 			syslog(LOG_INFO,
542 			    "<%s> interface %s becomes up. restart timer.",
543 			    __FUNCTION__, rai->ifname);
544 
545 			rai->initcounter = 0; /* reset the counter */
546 			rai->waiting = 0; /* XXX */
547 			rai->timer = rtadvd_add_timer(ra_timeout,
548 			    ra_timer_update, rai, rai);
549 			ra_timer_update((void *)rai, &rai->timer->tm);
550 			rtadvd_set_timer(&rai->timer->tm, rai->timer);
551 		}
552 	}
553 
554 	return;
555 }
556 
557 void
558 rtadvd_input()
559 {
560 	int i;
561 	int *hlimp = NULL;
562 #ifdef OLDRAWSOCKET
563 	struct ip6_hdr *ip;
564 #endif
565 	struct icmp6_hdr *icp;
566 	int ifindex = 0;
567 	struct cmsghdr *cm;
568 	struct in6_pktinfo *pi = NULL;
569 	u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
570 	struct in6_addr dst = in6addr_any;
571 
572 	/*
573 	 * Get message. We reset msg_controllen since the field could
574 	 * be modified if we had received a message before setting
575 	 * receive options.
576 	 */
577 	rcvmhdr.msg_controllen = rcvcmsgbuflen;
578 	if ((i = recvmsg(sock, &rcvmhdr, 0)) < 0)
579 		return;
580 
581 	/* extract optional information via Advanced API */
582 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr);
583 	     cm;
584 	     cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) {
585 		if (cm->cmsg_level == IPPROTO_IPV6 &&
586 		    cm->cmsg_type == IPV6_PKTINFO &&
587 		    cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) {
588 			pi = (struct in6_pktinfo *)(CMSG_DATA(cm));
589 			ifindex = pi->ipi6_ifindex;
590 			dst = pi->ipi6_addr;
591 		}
592 		if (cm->cmsg_level == IPPROTO_IPV6 &&
593 		    cm->cmsg_type == IPV6_HOPLIMIT &&
594 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
595 			hlimp = (int *)CMSG_DATA(cm);
596 	}
597 	if (ifindex == 0) {
598 		syslog(LOG_ERR,
599 		       "<%s> failed to get receiving interface",
600 		       __FUNCTION__);
601 		return;
602 	}
603 	if (hlimp == NULL) {
604 		syslog(LOG_ERR,
605 		       "<%s> failed to get receiving hop limit",
606 		       __FUNCTION__);
607 		return;
608 	}
609 
610 	/*
611 	 * If we happen to receive data on an interface which is now down,
612 	 * just discard the data.
613 	 */
614 	if ((iflist[pi->ipi6_ifindex]->ifm_flags & IFF_UP) == 0) {
615 		syslog(LOG_INFO,
616 		       "<%s> received data on a disabled interface (%s)",
617 		       __FUNCTION__,
618 		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
619 		return;
620 	}
621 
622 #ifdef OLDRAWSOCKET
623 	if (i < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) {
624 		syslog(LOG_ERR,
625 		       "<%s> packet size(%d) is too short",
626 		       __FUNCTION__, i);
627 		return;
628 	}
629 
630 	ip = (struct ip6_hdr *)rcvmhdr.msg_iov[0].iov_base;
631 	icp = (struct icmp6_hdr *)(ip + 1); /* XXX: ext. hdr? */
632 #else
633 	if (i < sizeof(struct icmp6_hdr)) {
634 		syslog(LOG_ERR,
635 		       "<%s> packet size(%d) is too short",
636 		       __FUNCTION__, i);
637 		return;
638 	}
639 
640 	icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base;
641 #endif
642 
643 	switch (icp->icmp6_type) {
644 	case ND_ROUTER_SOLICIT:
645 		/*
646 		 * Message verification - RFC-2461 6.1.1
647 		 * XXX: these checks must be done in the kernel as well,
648 		 *      but we can't completely rely on them.
649 		 */
650 		if (*hlimp != 255) {
651 			syslog(LOG_NOTICE,
652 			    "<%s> RS with invalid hop limit(%d) "
653 			    "received from %s on %s",
654 			    __FUNCTION__, *hlimp,
655 			    inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
656 			    INET6_ADDRSTRLEN),
657 			    if_indextoname(pi->ipi6_ifindex, ifnamebuf));
658 			return;
659 		}
660 		if (icp->icmp6_code) {
661 			syslog(LOG_NOTICE,
662 			    "<%s> RS with invalid ICMP6 code(%d) "
663 			    "received from %s on %s",
664 			    __FUNCTION__, icp->icmp6_code,
665 			    inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
666 			    INET6_ADDRSTRLEN),
667 			    if_indextoname(pi->ipi6_ifindex, ifnamebuf));
668 			return;
669 		}
670 		if (i < sizeof(struct nd_router_solicit)) {
671 			syslog(LOG_NOTICE,
672 			    "<%s> RS from %s on %s does not have enough "
673 			    "length (len = %d)",
674 			    __FUNCTION__,
675 			    inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
676 			    INET6_ADDRSTRLEN),
677 			    if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
678 			return;
679 		}
680 		rs_input(i, (struct nd_router_solicit *)icp, pi, &from);
681 		break;
682 	case ND_ROUTER_ADVERT:
683 		/*
684 		 * Message verification - RFC-2461 6.1.2
685 		 * XXX: there's a same dilemma as above...
686 		 */
687 		if (*hlimp != 255) {
688 			syslog(LOG_NOTICE,
689 			    "<%s> RA with invalid hop limit(%d) "
690 			    "received from %s on %s",
691 			    __FUNCTION__, *hlimp,
692 			    inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
693 			    INET6_ADDRSTRLEN),
694 			    if_indextoname(pi->ipi6_ifindex, ifnamebuf));
695 			return;
696 		}
697 		if (icp->icmp6_code) {
698 			syslog(LOG_NOTICE,
699 			    "<%s> RA with invalid ICMP6 code(%d) "
700 			    "received from %s on %s",
701 			    __FUNCTION__, icp->icmp6_code,
702 			    inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
703 			    INET6_ADDRSTRLEN),
704 			    if_indextoname(pi->ipi6_ifindex, ifnamebuf));
705 			return;
706 		}
707 		if (i < sizeof(struct nd_router_advert)) {
708 			syslog(LOG_NOTICE,
709 			    "<%s> RA from %s on %s does not have enough "
710 			    "length (len = %d)",
711 			    __FUNCTION__,
712 			    inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
713 			    INET6_ADDRSTRLEN),
714 			    if_indextoname(pi->ipi6_ifindex, ifnamebuf), i);
715 			return;
716 		}
717 		ra_input(i, (struct nd_router_advert *)icp, pi, &from);
718 		break;
719 	case ICMP6_ROUTER_RENUMBERING:
720 		if (accept_rr == 0) {
721 			syslog(LOG_ERR, "<%s> received a router renumbering "
722 			    "message, but not allowed to be accepted",
723 			    __FUNCTION__);
724 			break;
725 		}
726 		rr_input(i, (struct icmp6_router_renum *)icp, pi, &from,
727 			 &dst);
728 		break;
729 	default:
730 		/*
731 		 * Note that this case is POSSIBLE, especially just
732 		 * after invocation of the daemon. This is because we
733 		 * could receive message after opening the socket and
734 		 * before setting ICMP6 type filter(see sock_open()).
735 		 */
736 		syslog(LOG_ERR, "<%s> invalid icmp type(%d)",
737 		    __FUNCTION__, icp->icmp6_type);
738 		return;
739 	}
740 
741 	return;
742 }
743 
744 static void
745 rs_input(int len, struct nd_router_solicit *rs,
746 	 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
747 {
748 	u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
749 	union nd_opts ndopts;
750 	struct rainfo *ra;
751 
752 	syslog(LOG_DEBUG,
753 	       "<%s> RS received from %s on %s",
754 	       __FUNCTION__,
755 	       inet_ntop(AF_INET6, &from->sin6_addr,
756 			 ntopbuf, INET6_ADDRSTRLEN),
757 	       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
758 
759 	/* ND option check */
760 	memset(&ndopts, 0, sizeof(ndopts));
761 	if (nd6_options((struct nd_opt_hdr *)(rs + 1),
762 			len - sizeof(struct nd_router_solicit),
763 			 &ndopts, NDOPT_FLAG_SRCLINKADDR)) {
764 		syslog(LOG_DEBUG,
765 		       "<%s> ND option check failed for an RS from %s on %s",
766 		       __FUNCTION__,
767 		       inet_ntop(AF_INET6, &from->sin6_addr,
768 				 ntopbuf, INET6_ADDRSTRLEN),
769 		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
770 		return;
771 	}
772 
773 	/*
774 	 * If the IP source address is the unspecified address, there
775 	 * must be no source link-layer address option in the message.
776 	 * (RFC-2461 6.1.1)
777 	 */
778 	if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) &&
779 	    ndopts.nd_opts_src_lladdr) {
780 		syslog(LOG_ERR,
781 		       "<%s> RS from unspecified src on %s has a link-layer"
782 		       " address option",
783 		       __FUNCTION__,
784 		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
785 		goto done;
786 	}
787 
788 	ra = ralist;
789 	while (ra != NULL) {
790 		if (pi->ipi6_ifindex == ra->ifindex)
791 			break;
792 		ra = ra->next;
793 	}
794 	if (ra == NULL) {
795 		syslog(LOG_INFO,
796 		       "<%s> RS received on non advertising interface(%s)",
797 		       __FUNCTION__,
798 		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
799 		goto done;
800 	}
801 
802 	ra->rsinput++;		/* increment statistics */
803 
804 	/*
805 	 * Decide whether to send RA according to the rate-limit
806 	 * consideration.
807 	 */
808 	{
809 		long delay;	/* must not be greater than 1000000 */
810 		struct timeval interval, now, min_delay, tm_tmp, *rest;
811 		struct soliciter *sol;
812 
813 		/*
814 		 * record sockaddr waiting for RA, if possible
815 		 */
816 		sol = (struct soliciter *)malloc(sizeof(*sol));
817 		if (sol) {
818 			sol->addr = *from;
819 			/*XXX RFC2553 need clarification on flowinfo */
820 			sol->addr.sin6_flowinfo = 0;
821 			sol->next = ra->soliciter;
822 			ra->soliciter = sol->next;
823 		}
824 
825 		/*
826 		 * If there is already a waiting RS packet, don't
827 		 * update the timer.
828 		 */
829 		if (ra->waiting++)
830 			goto done;
831 
832 		/*
833 		 * Compute a random delay. If the computed value
834 		 * corresponds to a time later than the time the next
835 		 * multicast RA is scheduled to be sent, ignore the random
836 		 * delay and send the advertisement at the
837 		 * already-scheduled time. RFC-2461 6.2.6
838 		 */
839 		delay = random() % MAX_RA_DELAY_TIME;
840 		interval.tv_sec = 0;
841 		interval.tv_usec = delay;
842 		rest = rtadvd_timer_rest(ra->timer);
843 		if (TIMEVAL_LT(*rest, interval)) {
844 			syslog(LOG_DEBUG,
845 			       "<%s> random delay is larger than "
846 			       "the rest of normal timer",
847 			       __FUNCTION__);
848 			interval = *rest;
849 		}
850 
851 		/*
852 		 * If we sent a multicast Router Advertisement within
853 		 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule
854 		 * the advertisement to be sent at a time corresponding to
855 		 * MIN_DELAY_BETWEEN_RAS plus the random value after the
856 		 * previous advertisement was sent.
857 		 */
858 		gettimeofday(&now, NULL);
859 		TIMEVAL_SUB(&now, &ra->lastsent, &tm_tmp);
860 		min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS;
861 		min_delay.tv_usec = 0;
862 		if (TIMEVAL_LT(tm_tmp, min_delay)) {
863 			TIMEVAL_SUB(&min_delay, &tm_tmp, &min_delay);
864 			TIMEVAL_ADD(&min_delay, &interval, &interval);
865 		}
866 		rtadvd_set_timer(&interval, ra->timer);
867 		goto done;
868 	}
869 
870   done:
871 	free_ndopts(&ndopts);
872 	return;
873 }
874 
875 static void
876 ra_input(int len, struct nd_router_advert *ra,
877 	 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
878 {
879 	struct rainfo *rai;
880 	u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
881 	union nd_opts ndopts;
882 	char *on_off[] = {"OFF", "ON"};
883 	u_int32_t reachabletime, retranstimer, mtu;
884 	int inconsistent = 0;
885 
886 	syslog(LOG_DEBUG,
887 	       "<%s> RA received from %s on %s",
888 	       __FUNCTION__,
889 	       inet_ntop(AF_INET6, &from->sin6_addr,
890 			 ntopbuf, INET6_ADDRSTRLEN),
891 	       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
892 
893 	/* ND option check */
894 	memset(&ndopts, 0, sizeof(ndopts));
895 	if (nd6_options((struct nd_opt_hdr *)(ra + 1),
896 			len - sizeof(struct nd_router_advert),
897 			&ndopts, NDOPT_FLAG_SRCLINKADDR |
898 			NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU)) {
899 		syslog(LOG_ERR,
900 		       "<%s> ND option check failed for an RA from %s on %s",
901 		       __FUNCTION__,
902 		       inet_ntop(AF_INET6, &from->sin6_addr,
903 				 ntopbuf, INET6_ADDRSTRLEN),
904 		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
905 		return;
906 	}
907 
908 	/*
909 	 * RA consistency check according to RFC-2461 6.2.7
910 	 */
911 	if ((rai = if_indextorainfo(pi->ipi6_ifindex)) == 0) {
912 		syslog(LOG_INFO,
913 		       "<%s> received RA from %s on non-advertising"
914 		       " interface(%s)",
915 		       __FUNCTION__,
916 		       inet_ntop(AF_INET6, &from->sin6_addr,
917 				 ntopbuf, INET6_ADDRSTRLEN),
918 		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
919 		goto done;
920 	}
921 	rai->rainput++;		/* increment statistics */
922 
923 	/* Cur Hop Limit value */
924 	if (ra->nd_ra_curhoplimit && rai->hoplimit &&
925 	    ra->nd_ra_curhoplimit != rai->hoplimit) {
926 		syslog(LOG_INFO,
927 		       "<%s> CurHopLimit inconsistent on %s:"
928 		       " %d from %s, %d from us",
929 		       __FUNCTION__,
930 		       rai->ifname,
931 		       ra->nd_ra_curhoplimit,
932 		       inet_ntop(AF_INET6, &from->sin6_addr,
933 				 ntopbuf, INET6_ADDRSTRLEN),
934 		       rai->hoplimit);
935 		inconsistent++;
936 	}
937 	/* M flag */
938 	if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) !=
939 	    rai->managedflg) {
940 		syslog(LOG_INFO,
941 		       "<%s> M flag inconsistent on %s:"
942 		       " %s from %s, %s from us",
943 		       __FUNCTION__,
944 		       rai->ifname,
945 		       on_off[!rai->managedflg],
946 		       inet_ntop(AF_INET6, &from->sin6_addr,
947 				 ntopbuf, INET6_ADDRSTRLEN),
948 		       on_off[rai->managedflg]);
949 		inconsistent++;
950 	}
951 	/* O flag */
952 	if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) !=
953 	    rai->otherflg) {
954 		syslog(LOG_INFO,
955 		       "<%s> O flag inconsistent on %s:"
956 		       " %s from %s, %s from us",
957 		       __FUNCTION__,
958 		       rai->ifname,
959 		       on_off[!rai->otherflg],
960 		       inet_ntop(AF_INET6, &from->sin6_addr,
961 				 ntopbuf, INET6_ADDRSTRLEN),
962 		       on_off[rai->otherflg]);
963 		inconsistent++;
964 	}
965 	/* Reachable Time */
966 	reachabletime = ntohl(ra->nd_ra_reachable);
967 	if (reachabletime && rai->reachabletime &&
968 	    reachabletime != rai->reachabletime) {
969 		syslog(LOG_INFO,
970 		       "<%s> ReachableTime inconsistent on %s:"
971 		       " %d from %s, %d from us",
972 		       __FUNCTION__,
973 		       rai->ifname,
974 		       reachabletime,
975 		       inet_ntop(AF_INET6, &from->sin6_addr,
976 				 ntopbuf, INET6_ADDRSTRLEN),
977 		       rai->reachabletime);
978 		inconsistent++;
979 	}
980 	/* Retrans Timer */
981 	retranstimer = ntohl(ra->nd_ra_retransmit);
982 	if (retranstimer && rai->retranstimer &&
983 	    retranstimer != rai->retranstimer) {
984 		syslog(LOG_INFO,
985 		       "<%s> RetranceTimer inconsistent on %s:"
986 		       " %d from %s, %d from us",
987 		       __FUNCTION__,
988 		       rai->ifname,
989 		       retranstimer,
990 		       inet_ntop(AF_INET6, &from->sin6_addr,
991 				 ntopbuf, INET6_ADDRSTRLEN),
992 		       rai->retranstimer);
993 		inconsistent++;
994 	}
995 	/* Values in the MTU options */
996 	if (ndopts.nd_opts_mtu) {
997 		mtu = ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
998 		if (mtu && rai->linkmtu && mtu != rai->linkmtu) {
999 			syslog(LOG_INFO,
1000 			       "<%s> MTU option value inconsistent on %s:"
1001 			       " %d from %s, %d from us",
1002 			       __FUNCTION__,
1003 			       rai->ifname, mtu,
1004 			       inet_ntop(AF_INET6, &from->sin6_addr,
1005 					 ntopbuf, INET6_ADDRSTRLEN),
1006 			       rai->linkmtu);
1007 			inconsistent++;
1008 		}
1009 	}
1010 	/* Preferred and Valid Lifetimes for prefixes */
1011 	{
1012 		struct nd_optlist *optp = ndopts.nd_opts_list;
1013 
1014 		if (ndopts.nd_opts_pi) {
1015 			if (prefix_check(ndopts.nd_opts_pi, rai, from))
1016 				inconsistent++;
1017 		}
1018 		while (optp) {
1019 			if (prefix_check((struct nd_opt_prefix_info *)optp->opt,
1020 					 rai, from))
1021 				inconsistent++;
1022 			optp = optp->next;
1023 		}
1024 	}
1025 
1026 	if (inconsistent)
1027 		rai->rainconsistent++;
1028 
1029   done:
1030 	free_ndopts(&ndopts);
1031 	return;
1032 }
1033 
1034 /* return a non-zero value if the received prefix is inconsitent with ours */
1035 static int
1036 prefix_check(struct nd_opt_prefix_info *pinfo,
1037 	     struct rainfo *rai, struct sockaddr_in6 *from)
1038 {
1039 	u_int32_t preferred_time, valid_time;
1040 	struct prefix *pp;
1041 	int inconsistent = 0;
1042 	u_char ntopbuf[INET6_ADDRSTRLEN], prefixbuf[INET6_ADDRSTRLEN];
1043 	struct timeval now;
1044 
1045 #if 0				/* impossible */
1046 	if (pinfo->nd_opt_pi_type != ND_OPT_PREFIX_INFORMATION)
1047 		return(0);
1048 #endif
1049 
1050 	/*
1051 	 * log if the adveritsed prefix has link-local scope(sanity check?)
1052 	 */
1053 	if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) {
1054 		syslog(LOG_INFO,
1055 		       "<%s> link-local prefix %s/%d is advertised "
1056 		       "from %s on %s",
1057 		       __FUNCTION__,
1058 		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1059 				 prefixbuf, INET6_ADDRSTRLEN),
1060 		       pinfo->nd_opt_pi_prefix_len,
1061 		       inet_ntop(AF_INET6, &from->sin6_addr,
1062 				 ntopbuf, INET6_ADDRSTRLEN),
1063 		       rai->ifname);
1064 	}
1065 
1066 	if ((pp = find_prefix(rai, &pinfo->nd_opt_pi_prefix,
1067 			      pinfo->nd_opt_pi_prefix_len)) == NULL) {
1068 		syslog(LOG_INFO,
1069 		       "<%s> prefix %s/%d from %s on %s is not in our list",
1070 		       __FUNCTION__,
1071 		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1072 				 prefixbuf, INET6_ADDRSTRLEN),
1073 		       pinfo->nd_opt_pi_prefix_len,
1074 		       inet_ntop(AF_INET6, &from->sin6_addr,
1075 				 ntopbuf, INET6_ADDRSTRLEN),
1076 		       rai->ifname);
1077 		return(0);
1078 	}
1079 
1080 	preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time);
1081 	if (pp->pltimeexpire) {
1082 		/*
1083 		 * The lifetime is decremented in real time, so we should
1084 		 * compare the expiration time.
1085 		 * (RFC 2461 Section 6.2.7.)
1086 		 * XXX: can we really expect that all routers on the link
1087 		 * have synchronized clocks?
1088 		 */
1089 		gettimeofday(&now, NULL);
1090 		preferred_time += now.tv_sec;
1091 
1092 		if (rai->clockskew &&
1093 		    abs(preferred_time - pp->pltimeexpire) > rai->clockskew) {
1094 			syslog(LOG_INFO,
1095 			       "<%s> prefeerred lifetime for %s/%d"
1096 			       " (decr. in real time) inconsistent on %s:"
1097 			       " %d from %s, %ld from us",
1098 			       __FUNCTION__,
1099 			       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1100 					 prefixbuf, INET6_ADDRSTRLEN),
1101 			       pinfo->nd_opt_pi_prefix_len,
1102 			       rai->ifname, preferred_time,
1103 			       inet_ntop(AF_INET6, &from->sin6_addr,
1104 					 ntopbuf, INET6_ADDRSTRLEN),
1105 			       pp->pltimeexpire);
1106 			inconsistent++;
1107 		}
1108 	} else if (preferred_time != pp->preflifetime) {
1109 		syslog(LOG_INFO,
1110 		       "<%s> prefeerred lifetime for %s/%d"
1111 		       " inconsistent on %s:"
1112 		       " %d from %s, %d from us",
1113 		       __FUNCTION__,
1114 		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1115 				 prefixbuf, INET6_ADDRSTRLEN),
1116 		       pinfo->nd_opt_pi_prefix_len,
1117 		       rai->ifname, preferred_time,
1118 		       inet_ntop(AF_INET6, &from->sin6_addr,
1119 				 ntopbuf, INET6_ADDRSTRLEN),
1120 		       pp->preflifetime);
1121 	}
1122 
1123 	valid_time = ntohl(pinfo->nd_opt_pi_valid_time);
1124 	if (pp->vltimeexpire) {
1125 		gettimeofday(&now, NULL);
1126 		valid_time += now.tv_sec;
1127 
1128 		if (rai->clockskew &&
1129 		    abs(valid_time - pp->vltimeexpire) > rai->clockskew) {
1130 			syslog(LOG_INFO,
1131 			       "<%s> valid lifetime for %s/%d"
1132 			       " (decr. in real time) inconsistent on %s:"
1133 			       " %d from %s, %ld from us",
1134 			       __FUNCTION__,
1135 			       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1136 					 prefixbuf, INET6_ADDRSTRLEN),
1137 			       pinfo->nd_opt_pi_prefix_len,
1138 			       rai->ifname, preferred_time,
1139 			       inet_ntop(AF_INET6, &from->sin6_addr,
1140 					 ntopbuf, INET6_ADDRSTRLEN),
1141 			       pp->vltimeexpire);
1142 			inconsistent++;
1143 		}
1144 	} else if (valid_time != pp->validlifetime) {
1145 		syslog(LOG_INFO,
1146 		       "<%s> valid lifetime for %s/%d"
1147 		       " inconsistent on %s:"
1148 		       " %d from %s, %d from us",
1149 		       __FUNCTION__,
1150 		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
1151 				 prefixbuf, INET6_ADDRSTRLEN),
1152 		       pinfo->nd_opt_pi_prefix_len,
1153 		       rai->ifname, valid_time,
1154 		       inet_ntop(AF_INET6, &from->sin6_addr,
1155 				 ntopbuf, INET6_ADDRSTRLEN),
1156 		       pp->validlifetime);
1157 		inconsistent++;
1158 	}
1159 
1160 	return(inconsistent);
1161 }
1162 
1163 struct prefix *
1164 find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen)
1165 {
1166 	struct prefix *pp;
1167 	int bytelen, bitlen;
1168 
1169 	for (pp = rai->prefix.next; pp != &rai->prefix; pp = pp->next) {
1170 		if (plen != pp->prefixlen)
1171 			continue;
1172 		bytelen = plen / 8;
1173 		bitlen = plen % 8;
1174 		if (memcmp((void *)prefix, (void *)&pp->prefix, bytelen))
1175 			continue;
1176 		if (prefix->s6_addr[bytelen] >> (8 - bitlen) ==
1177 		    pp->prefix.s6_addr[bytelen] >> (8 - bitlen))
1178 			return(pp);
1179 	}
1180 
1181 	return(NULL);
1182 }
1183 
1184 /* check if p0/plen0 matches p1/plen1; return 1 if matches, otherwise 0. */
1185 int
1186 prefix_match(struct in6_addr *p0, int plen0,
1187 	     struct in6_addr *p1, int plen1)
1188 {
1189 	int bytelen, bitlen;
1190 
1191 	if (plen0 < plen1)
1192 		return(0);
1193 	bytelen = plen1 / 8;
1194 	bitlen = plen1 % 8;
1195 	if (memcmp((void *)p0, (void *)p1, bytelen))
1196 		return(0);
1197 	if (p0->s6_addr[bytelen] >> (8 - bitlen) ==
1198 	    p1->s6_addr[bytelen] >> (8 - bitlen))
1199 		return(1);
1200 
1201 	return(0);
1202 }
1203 
1204 static int
1205 nd6_options(struct nd_opt_hdr *hdr, int limit,
1206 	    union nd_opts *ndopts, u_int32_t optflags)
1207 {
1208 	int optlen = 0;
1209 
1210 	for (; limit > 0; limit -= optlen) {
1211 		hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen);
1212 		optlen = hdr->nd_opt_len << 3;
1213 		if (hdr->nd_opt_len == 0) {
1214 			syslog(LOG_ERR,
1215 			    "<%s> bad ND option length(0) (type = %d)",
1216 			    __FUNCTION__, hdr->nd_opt_type);
1217 			goto bad;
1218 		}
1219 
1220 		if (hdr->nd_opt_type > ND_OPT_MTU) {
1221 			syslog(LOG_INFO,
1222 			    "<%s> unknown ND option(type %d)",
1223 			    __FUNCTION__, hdr->nd_opt_type);
1224 			continue;
1225 		}
1226 
1227 		if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) {
1228 			syslog(LOG_INFO,
1229 			    "<%s> unexpected ND option(type %d)",
1230 			       __FUNCTION__, hdr->nd_opt_type);
1231 			continue;
1232 		}
1233 
1234 		switch (hdr->nd_opt_type) {
1235 		case ND_OPT_SOURCE_LINKADDR:
1236 		case ND_OPT_TARGET_LINKADDR:
1237 		case ND_OPT_REDIRECTED_HEADER:
1238 		case ND_OPT_MTU:
1239 			if (ndopts->nd_opt_array[hdr->nd_opt_type]) {
1240 				syslog(LOG_INFO,
1241 				    "<%s> duplicated ND option (type = %d)",
1242 				    __FUNCTION__, hdr->nd_opt_type);
1243 			}
1244 			ndopts->nd_opt_array[hdr->nd_opt_type] = hdr;
1245 			break;
1246 		case ND_OPT_PREFIX_INFORMATION:
1247 		{
1248 			struct nd_optlist *pfxlist;
1249 
1250 			if (ndopts->nd_opts_pi == 0) {
1251 				ndopts->nd_opts_pi =
1252 				    (struct nd_opt_prefix_info *)hdr;
1253 				continue;
1254 			}
1255 			if ((pfxlist = malloc(sizeof(*pfxlist))) == NULL) {
1256 				syslog(LOG_ERR, "<%s> can't allocate memory",
1257 				    __FUNCTION__);
1258 				goto bad;
1259 			}
1260 			pfxlist->next = ndopts->nd_opts_list;
1261 			pfxlist->opt = hdr;
1262 			ndopts->nd_opts_list = pfxlist;
1263 
1264 			break;
1265 		}
1266 		default:	/* impossible */
1267 			break;
1268 		}
1269 	}
1270 
1271 	return(0);
1272 
1273   bad:
1274 	free_ndopts(ndopts);
1275 
1276 	return(-1);
1277 }
1278 
1279 static void
1280 free_ndopts(union nd_opts *ndopts)
1281 {
1282 	struct nd_optlist *opt = ndopts->nd_opts_list, *next;
1283 
1284 	while (opt) {
1285 		next = opt->next;
1286 		free(opt);
1287 		opt = next;
1288 	}
1289 }
1290 
1291 void
1292 sock_open()
1293 {
1294 	struct icmp6_filter filt;
1295 	struct ipv6_mreq mreq;
1296 	struct rainfo *ra = ralist;
1297 	int on;
1298 	/* XXX: should be max MTU attached to the node */
1299 	static u_char answer[1500];
1300 
1301 	rcvcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1302 				CMSG_SPACE(sizeof(int));
1303 	rcvcmsgbuf = (u_char *)malloc(rcvcmsgbuflen);
1304 	if (rcvcmsgbuf == NULL) {
1305 		syslog(LOG_ERR, "<%s> not enough core", __FUNCTION__);
1306 		exit(1);
1307 	}
1308 
1309 	sndcmsgbuflen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
1310 				CMSG_SPACE(sizeof(int));
1311 	sndcmsgbuf = (u_char *)malloc(sndcmsgbuflen);
1312 	if (sndcmsgbuf == NULL) {
1313 		syslog(LOG_ERR, "<%s> not enough core", __FUNCTION__);
1314 		exit(1);
1315 	}
1316 
1317 	if ((sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
1318 		syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__,
1319 		       strerror(errno));
1320 		exit(1);
1321 	}
1322 
1323 	/* specify to tell receiving interface */
1324 	on = 1;
1325 #ifdef IPV6_RECVPKTINFO
1326 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
1327 		       sizeof(on)) < 0) {
1328 		syslog(LOG_ERR, "<%s> IPV6_RECVPKTINFO: %s",
1329 		       __FUNCTION__, strerror(errno));
1330 		exit(1);
1331 	}
1332 #else  /* old adv. API */
1333 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_PKTINFO, &on,
1334 		       sizeof(on)) < 0) {
1335 		syslog(LOG_ERR, "<%s> IPV6_PKTINFO: %s",
1336 		       __FUNCTION__, strerror(errno));
1337 		exit(1);
1338 	}
1339 #endif
1340 
1341 	on = 1;
1342 	/* specify to tell value of hoplimit field of received IP6 hdr */
1343 #ifdef IPV6_RECVHOPLIMIT
1344 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
1345 		       sizeof(on)) < 0) {
1346 		syslog(LOG_ERR, "<%s> IPV6_RECVHOPLIMIT: %s",
1347 		       __FUNCTION__, strerror(errno));
1348 		exit(1);
1349 	}
1350 #else  /* old adv. API */
1351 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
1352 		       sizeof(on)) < 0) {
1353 		syslog(LOG_ERR, "<%s> IPV6_HOPLIMIT: %s",
1354 		       __FUNCTION__, strerror(errno));
1355 		exit(1);
1356 	}
1357 #endif
1358 
1359 	ICMP6_FILTER_SETBLOCKALL(&filt);
1360 	ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
1361 	ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
1362 	if (accept_rr)
1363 		ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt);
1364 	if (setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
1365 		       sizeof(filt)) < 0) {
1366 		syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s",
1367 		       __FUNCTION__, strerror(errno));
1368 		exit(1);
1369 	}
1370 
1371 	/*
1372 	 * join all routers multicast address on each advertising interface.
1373 	 */
1374 	if (inet_pton(AF_INET6, ALLROUTERS_LINK,
1375 		      &mreq.ipv6mr_multiaddr.s6_addr)
1376 	    != 1) {
1377 		syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)",
1378 		       __FUNCTION__);
1379 		exit(1);
1380 	}
1381 	while (ra) {
1382 		mreq.ipv6mr_interface = ra->ifindex;
1383 		if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
1384 			       sizeof(mreq)) < 0) {
1385 			syslog(LOG_ERR, "<%s> IPV6_JOIN_GROUP(link) on %s: %s",
1386 			       __FUNCTION__, ra->ifname, strerror(errno));
1387 			exit(1);
1388 		}
1389 		ra = ra->next;
1390 	}
1391 
1392 	/*
1393 	 * When attending router renumbering, join all-routers site-local
1394 	 * multicast group.
1395 	 */
1396 	if (accept_rr) {
1397 		if (inet_pton(AF_INET6, ALLROUTERS_SITE,
1398 			      &in6a_site_allrouters) != 1) {
1399 			syslog(LOG_ERR, "<%s> inet_pton failed(library bug?)",
1400 			       __FUNCTION__);
1401 			exit(1);
1402 		}
1403 		mreq.ipv6mr_multiaddr = in6a_site_allrouters;
1404 		if (mcastif) {
1405 			if ((mreq.ipv6mr_interface = if_nametoindex(mcastif))
1406 			    == 0) {
1407 				syslog(LOG_ERR,
1408 				       "<%s> invalid interface: %s",
1409 				       __FUNCTION__, mcastif);
1410 				exit(1);
1411 			}
1412 		} else
1413 			mreq.ipv6mr_interface = ralist->ifindex;
1414 		if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP,
1415 			       &mreq, sizeof(mreq)) < 0) {
1416 			syslog(LOG_ERR,
1417 			       "<%s> IPV6_JOIN_GROUP(site) on %s: %s",
1418 			       __FUNCTION__,
1419 			       mcastif ? mcastif : ralist->ifname,
1420 			       strerror(errno));
1421 			exit(1);
1422 		}
1423 	}
1424 
1425 	/* initialize msghdr for receiving packets */
1426 	rcviov[0].iov_base = (caddr_t)answer;
1427 	rcviov[0].iov_len = sizeof(answer);
1428 	rcvmhdr.msg_name = (caddr_t)&from;
1429 	rcvmhdr.msg_namelen = sizeof(from);
1430 	rcvmhdr.msg_iov = rcviov;
1431 	rcvmhdr.msg_iovlen = 1;
1432 	rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
1433 	rcvmhdr.msg_controllen = rcvcmsgbuflen;
1434 
1435 	/* initialize msghdr for sending packets */
1436 	sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
1437 	sndmhdr.msg_iov = sndiov;
1438 	sndmhdr.msg_iovlen = 1;
1439 	sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
1440 	sndmhdr.msg_controllen = sndcmsgbuflen;
1441 
1442 	return;
1443 }
1444 
1445 /* open a routing socket to watch the routing table */
1446 static void
1447 rtsock_open()
1448 {
1449 	if ((rtsock = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) {
1450 		syslog(LOG_ERR,
1451 		       "<%s> socket: %s", __FUNCTION__, strerror(errno));
1452 		exit(1);
1453 	}
1454 }
1455 
1456 struct rainfo *
1457 if_indextorainfo(int index)
1458 {
1459 	struct rainfo *rai = ralist;
1460 
1461 	for (rai = ralist; rai; rai = rai->next) {
1462 		if (rai->ifindex == index)
1463 			return(rai);
1464 	}
1465 
1466 	return(NULL);		/* search failed */
1467 }
1468 
1469 static void
1470 ra_output(rainfo)
1471 struct rainfo *rainfo;
1472 {
1473 	int i;
1474 	struct cmsghdr *cm;
1475 	struct in6_pktinfo *pi;
1476 	struct soliciter *sol, *nextsol;
1477 
1478 	if ((iflist[rainfo->ifindex]->ifm_flags & IFF_UP) == 0) {
1479 		syslog(LOG_DEBUG, "<%s> %s is not up, skip sending RA",
1480 		       __FUNCTION__, rainfo->ifname);
1481 		return;
1482 	}
1483 
1484 	make_packet(rainfo);	/* XXX: inefficient */
1485 
1486 	sndmhdr.msg_name = (caddr_t)&sin6_allnodes;
1487 	sndmhdr.msg_iov[0].iov_base = (caddr_t)rainfo->ra_data;
1488 	sndmhdr.msg_iov[0].iov_len = rainfo->ra_datalen;
1489 
1490 	cm = CMSG_FIRSTHDR(&sndmhdr);
1491 	/* specify the outgoing interface */
1492 	cm->cmsg_level = IPPROTO_IPV6;
1493 	cm->cmsg_type = IPV6_PKTINFO;
1494 	cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
1495 	pi = (struct in6_pktinfo *)CMSG_DATA(cm);
1496 	memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr));	/*XXX*/
1497 	pi->ipi6_ifindex = rainfo->ifindex;
1498 
1499 	/* specify the hop limit of the packet */
1500 	{
1501 		int hoplimit = 255;
1502 
1503 		cm = CMSG_NXTHDR(&sndmhdr, cm);
1504 		cm->cmsg_level = IPPROTO_IPV6;
1505 		cm->cmsg_type = IPV6_HOPLIMIT;
1506 		cm->cmsg_len = CMSG_LEN(sizeof(int));
1507 		memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
1508 	}
1509 
1510 	syslog(LOG_DEBUG,
1511 	       "<%s> send RA on %s, # of waitings = %d",
1512 	       __FUNCTION__, rainfo->ifname, rainfo->waiting);
1513 
1514 	i = sendmsg(sock, &sndmhdr, 0);
1515 
1516 	if (i < 0 || i != rainfo->ra_datalen)  {
1517 		if (i < 0) {
1518 			syslog(LOG_ERR, "<%s> sendmsg on %s: %s",
1519 			       __FUNCTION__, rainfo->ifname,
1520 			       strerror(errno));
1521 		}
1522 	}
1523 
1524 	/*
1525 	 * unicast advertisements
1526 	 * XXX commented out.  reason: though spec does not forbit it, unicast
1527 	 * advert does not really help
1528 	 */
1529 	for (sol = rainfo->soliciter; sol; sol = nextsol) {
1530 		nextsol = sol->next;
1531 
1532 #if 0
1533 		sndmhdr.msg_name = (caddr_t)&sol->addr;
1534 		i = sendmsg(sock, &sndmhdr, 0);
1535 		if (i < 0 || i != rainfo->ra_datalen)  {
1536 			if (i < 0) {
1537 				syslog(LOG_ERR,
1538 				    "<%s> unicast sendmsg on %s: %s",
1539 				    __FUNCTION__, rainfo->ifname,
1540 				    strerror(errno));
1541 			}
1542 		}
1543 #endif
1544 
1545 		sol->next = NULL;
1546 		free(sol);
1547 	}
1548 	rainfo->soliciter = NULL;
1549 
1550 	/* update counter */
1551 	if (rainfo->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS)
1552 		rainfo->initcounter++;
1553 	rainfo->raoutput++;
1554 
1555 	/* update timestamp */
1556 	gettimeofday(&rainfo->lastsent, NULL);
1557 
1558 	/* reset waiting conter */
1559 	rainfo->waiting = 0;
1560 }
1561 
1562 /* process RA timer */
1563 struct rtadvd_timer *
1564 ra_timeout(void *data)
1565 {
1566 	struct rainfo *rai = (struct rainfo *)data;
1567 
1568 #ifdef notyet
1569 	/* if necessary, reconstruct the packet. */
1570 #endif
1571 
1572 	syslog(LOG_DEBUG,
1573 	       "<%s> RA timer on %s is expired",
1574 	       __FUNCTION__, rai->ifname);
1575 
1576 	ra_output(rai);
1577 
1578 	return(rai->timer);
1579 }
1580 
1581 /* update RA timer */
1582 void
1583 ra_timer_update(void *data, struct timeval *tm)
1584 {
1585 	struct rainfo *rai = (struct rainfo *)data;
1586 	long interval;
1587 
1588 	/*
1589 	 * Whenever a multicast advertisement is sent from an interface,
1590 	 * the timer is reset to a uniformly-distributed random value
1591 	 * between the interface's configured MinRtrAdvInterval and
1592 	 * MaxRtrAdvInterval (RFC2461 6.2.4).
1593 	 */
1594 	interval = rai->mininterval;
1595 	interval += random() % (rai->maxinterval - rai->mininterval);
1596 
1597 	/*
1598 	 * For the first few advertisements (up to
1599 	 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen interval
1600 	 * is greater than MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer
1601 	 * SHOULD be set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead.
1602 	 * (RFC-2461 6.2.4)
1603 	 */
1604 	if (rai->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS &&
1605 	    interval > MAX_INITIAL_RTR_ADVERT_INTERVAL)
1606 		interval = MAX_INITIAL_RTR_ADVERT_INTERVAL;
1607 
1608 	tm->tv_sec = interval;
1609 	tm->tv_usec = 0;
1610 
1611 	syslog(LOG_DEBUG,
1612 	       "<%s> RA timer on %s is set to %ld:%ld",
1613 	       __FUNCTION__, rai->ifname,
1614 	       (long int)tm->tv_sec, (long int)tm->tv_usec);
1615 
1616 	return;
1617 }
1618