xref: /netbsd-src/usr.sbin/rtadvd/config.c (revision 89c5a767f8fc7a4633b2d409966e2becbb98ff92)
1 /*	$NetBSD: config.c,v 1.6 2000/03/13 06:16:46 itojun Exp $	*/
2 
3 /*
4  * Copyright (C) 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 
32 #include <sys/param.h>
33 #include <sys/ioctl.h>
34 #include <sys/socket.h>
35 #include <sys/time.h>
36 
37 #include <net/if.h>
38 #if defined(__FreeBSD__) && __FreeBSD__ >= 3
39 #include <net/if_var.h>
40 #endif /* __FreeBSD__ >= 3 */
41 #include <net/route.h>
42 #include <net/if_dl.h>
43 
44 #include <netinet/in.h>
45 #include <netinet/in_var.h>
46 #include <netinet/ip6.h>
47 #include <netinet6/ip6_var.h>
48 #include <netinet/icmp6.h>
49 #ifdef MIP6
50 #include <netinet6/mip6.h>
51 #endif
52 
53 #include <arpa/inet.h>
54 
55 #include <stdio.h>
56 #include <syslog.h>
57 #include <errno.h>
58 #include <string.h>
59 #include <stdlib.h>
60 #ifdef __NetBSD__
61 #include <search.h>
62 #endif
63 #include <unistd.h>
64 
65 #include "rtadvd.h"
66 #include "advcap.h"
67 #include "timer.h"
68 #include "if.h"
69 #include "config.h"
70 
71 static void makeentry __P((char *, int, char *, int));
72 static void get_prefix __P((struct rainfo *));
73 
74 extern struct rainfo *ralist;
75 
76 void
77 getconfig(intface)
78 	char *intface;
79 {
80 	int stat, pfxs, i;
81 	char tbuf[BUFSIZ];
82 	struct rainfo *tmp;
83 	long val;
84 	char buf[BUFSIZ];
85 	char *bp = buf;
86 	char *addr;
87 
88 #define MUSTHAVE(var, cap)	\
89     do {								\
90 	int t;								\
91 	if ((t = agetnum(cap)) < 0) {					\
92 		fprintf(stderr, "rtadvd: need %s for interface %s\n",	\
93 			cap, intface);					\
94 		exit(1);						\
95 	}								\
96 	var = t;							\
97      } while (0)
98 #define MAYHAVE(var, cap, def)	\
99      do {								\
100 	if ((var = agetnum(cap)) < 0)					\
101 		var = def;						\
102      } while (0)
103 
104 	if ((stat = agetent(tbuf, intface)) <= 0) {
105 		memset(tbuf, 0, sizeof(tbuf));
106 		syslog(LOG_INFO,
107 		       "<%s> %s isn't defined in the configuration file"
108 		       " or the configuration file doesn't exist."
109 		       " Treat it as default",
110 		        __FUNCTION__, intface);
111 	}
112 
113 	tmp = (struct rainfo *)malloc(sizeof(*ralist));
114 	memset(tmp, 0, sizeof(*tmp));
115 	tmp->prefix.next = tmp->prefix.prev = &tmp->prefix;
116 
117 	/* get interface information */
118 	if (agetflag("nolladdr"))
119 		tmp->advlinkopt = 0;
120 	else
121 		tmp->advlinkopt = 1;
122 	if (tmp->advlinkopt) {
123 		if ((tmp->sdl = if_nametosdl(intface)) == NULL) {
124 			syslog(LOG_ERR,
125 			       "<%s> can't get information of %s",
126 			       __FUNCTION__, intface);
127 			exit(1);
128 		}
129 		tmp->ifindex = tmp->sdl->sdl_index;
130 	} else
131 		tmp->ifindex = if_nametoindex(intface);
132 	strncpy(tmp->ifname, intface, sizeof(tmp->ifname));
133 	if ((tmp->phymtu = if_getmtu(intface)) == 0) {
134 		tmp->phymtu = IPV6_MMTU;
135 		syslog(LOG_WARNING,
136 		       "<%s> can't get interface mtu of %s. Treat as %d",
137 		       __FUNCTION__, intface, IPV6_MMTU);
138 	}
139 
140 	/*
141 	 * set router configuration variables.
142 	 */
143 	MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL);
144 	if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) {
145 		syslog(LOG_ERR,
146 		       "<%s> maxinterval must be between %e and %u",
147 		       __FUNCTION__, MIN_MAXINTERVAL, MAX_MAXINTERVAL);
148 		exit(1);
149 	}
150 	tmp->maxinterval = (u_int)val;
151 	MAYHAVE(val, "mininterval", tmp->maxinterval/3);
152 	if (val < MIN_MININTERVAL || val > (tmp->maxinterval * 3) / 4) {
153 		syslog(LOG_ERR,
154 		       "<%s> mininterval must be between %e and %d",
155 		       __FUNCTION__,
156 		       MIN_MININTERVAL,
157 		       (tmp->maxinterval * 3) / 4);
158 		exit(1);
159 	}
160 	tmp->mininterval = (u_int)val;
161 
162 	MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT);
163 	tmp->hoplimit = val & 0xff;
164 
165 	MAYHAVE(val, "raflags", 0);
166 	tmp->managedflg= val & ND_RA_FLAG_MANAGED;
167 	tmp->otherflg = val & ND_RA_FLAG_OTHER;
168 #ifdef MIP6
169 	if (mobileip6)
170 		tmp->haflg = val & ND_RA_FLAG_HA;
171 #endif
172 
173 	MAYHAVE(val, "rltime", tmp->maxinterval * 3);
174 	if (val && (val < tmp->maxinterval || val > MAXROUTERLIFETIME)) {
175 		syslog(LOG_ERR,
176 		       "<%s> router lifetime on %s must be 0 or"
177 		       " between %d and %d",
178 		       __FUNCTION__, intface,
179 		       tmp->maxinterval, MAXROUTERLIFETIME);
180 		exit(1);
181 	}
182 	tmp->lifetime = val & 0xffff;
183 
184 	MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME);
185 	if (val > MAXREACHABLETIME) {
186 		syslog(LOG_ERR,
187 		       "<%s> reachable time must be no greater than %d",
188 		       __FUNCTION__, MAXREACHABLETIME);
189 		exit(1);
190 	}
191 	tmp->reachabletime = (u_int32_t)val;
192 
193 	MAYHAVE(val, "retrans", DEF_ADVRETRANSTIMER);
194 	if (val < 0 || val > 0xffffffff) {
195 		syslog(LOG_ERR,
196 		       "<%s> retrans time out of range", __FUNCTION__);
197 		exit(1);
198 	}
199 	tmp->retranstimer = (u_int32_t)val;
200 
201 #ifdef MIP6
202 	if (!mobileip6)
203 #else
204 	if (1)
205 #endif
206 	{
207 		if (agetstr("hapref", &bp) || agetstr("hatime", &bp)) {
208 			syslog(LOG_ERR,
209 			       "<%s> mobile-ip6 configuration without "
210 			       "proper command line option",
211 			       __FUNCTION__);
212 			exit(1);
213 		}
214 	}
215 #ifdef MIP6
216 	else {
217 		tmp->hapref = 0;
218 		if ((val = agetnum("hapref")) >= 0)
219 			tmp->hapref = (int16_t)val;
220 		if (tmp->hapref != 0) {
221 			tmp->hatime = 0;
222 			MUSTHAVE(val, "hatime");
223 			tmp->hatime = (u_int16_t)val;
224 			if (tmp->hatime <= 0) {
225 				syslog(LOG_ERR,
226 				       "<%s> home agent lifetime must be greater than 0",
227 				       __FUNCTION__);
228 				exit(1);
229 			}
230 		}
231 	}
232 #endif
233 
234 	/* prefix information */
235 	if ((pfxs = agetnum("addrs")) < 0) {
236 		/* auto configure prefix information */
237 		if (agetstr("addr", &bp) || agetstr("addr1", &bp)) {
238 			syslog(LOG_ERR,
239 			       "<%s> conflicting prefix configuration for %s: "
240 			       "automatic and manual config at the same time",
241 			       __FUNCTION__, intface);
242 			exit(1);
243 		}
244 		get_prefix(tmp);
245 	}
246 	else {
247 		tmp->pfxs = pfxs;
248 		for (i = 0; i < pfxs; i++) {
249 			struct prefix *pfx;
250 			char entbuf[256];
251 			int added = (pfxs > 1) ? 1 : 0;
252 
253 			/* allocate memory to store prefix information */
254 			if ((pfx = malloc(sizeof(struct prefix))) == NULL) {
255 				syslog(LOG_ERR,
256 				       "<%s> can't allocate enough memory",
257 				       __FUNCTION__);
258 				exit(1);
259 			}
260 			/* link into chain */
261 			insque(pfx, &tmp->prefix);
262 
263 			makeentry(entbuf, i, "prefixlen", added);
264 			MAYHAVE(val, entbuf, 64);
265 			if (val < 0 || val > 128) {
266 				syslog(LOG_ERR,
267 				       "<%s> prefixlen out of range",
268 				       __FUNCTION__);
269 				exit(1);
270 			}
271 			pfx->prefixlen = (int)val;
272 
273 			makeentry(entbuf, i, "pinfoflags", added);
274 #ifdef MIP6
275 			if (mobileip6)
276 			{
277 				MAYHAVE(val, entbuf,
278 				    (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO|
279 					 ND_OPT_PI_FLAG_RTADDR));
280 			} else
281 #endif
282 			{
283 				MAYHAVE(val, entbuf,
284 				    (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO));
285 			}
286 			pfx->onlinkflg = val & ND_OPT_PI_FLAG_ONLINK;
287 			pfx->autoconfflg = val & ND_OPT_PI_FLAG_AUTO;
288 #ifdef MIP6
289 			if (mobileip6)
290 				pfx->routeraddr = val & ND_OPT_PI_FLAG_RTADDR;
291 #endif
292 
293 			makeentry(entbuf, i, "vltime", added);
294 			MAYHAVE(val, entbuf, DEF_ADVVALIDLIFETIME);
295 			if (val < 0 || val > 0xffffffff) {
296 				syslog(LOG_ERR,
297 				       "<%s> vltime out of range",
298 				       __FUNCTION__);
299 				exit(1);
300 			}
301 			pfx->validlifetime = (u_int32_t)val;
302 
303 			makeentry(entbuf, i, "pltime", added);
304 			MAYHAVE(val, entbuf, DEF_ADVPREFERREDLIFETIME);
305 			if (val < 0 || val > 0xffffffff) {
306 				syslog(LOG_ERR,
307 				       "<%s> pltime out of range",
308 				       __FUNCTION__);
309 				exit(1);
310 			}
311 			pfx->preflifetime = (u_int32_t)val;
312 
313 			makeentry(entbuf, i, "addr", added);
314 			addr = (char *)agetstr(entbuf, &bp);
315 			if (addr == NULL) {
316 				syslog(LOG_ERR,
317 				       "<%s> need %s as an prefix for "
318 				       "interface %s",
319 				       __FUNCTION__, entbuf, intface);
320 				exit(1);
321 			}
322 			if (inet_pton(AF_INET6, addr,
323 				      &pfx->prefix) != 1) {
324 				syslog(LOG_ERR,
325 				       "<%s> inet_pton failed for %s",
326 				       __FUNCTION__, addr);
327 				exit(1);
328 			}
329 			if (IN6_IS_ADDR_MULTICAST(&pfx->prefix)) {
330 				syslog(LOG_ERR,
331 				       "<%s> multicast prefix(%s) must "
332 				       "not be advertised (IF=%s)",
333 				       __FUNCTION__, addr, intface);
334 				exit(1);
335 			}
336 			if (IN6_IS_ADDR_LINKLOCAL(&pfx->prefix))
337 				syslog(LOG_NOTICE,
338 				       "<%s> link-local prefix(%s) will be"
339 				       " advertised on %s",
340 				       __FUNCTION__, addr, intface);
341 		}
342 	}
343 
344 	MAYHAVE(val, "mtu", 0);
345 	if (val < 0 || val > 0xffffffff) {
346 		syslog(LOG_ERR,
347 		       "<%s> mtu out of range", __FUNCTION__);
348 		exit(1);
349 	}
350 	tmp->linkmtu = (u_int32_t)val;
351 	if (tmp->linkmtu == 0) {
352 		char *mtustr;
353 
354 		if ((mtustr = (char *)agetstr("mtu", &bp)) &&
355 		    strcmp(mtustr, "auto") == 0)
356 			tmp->linkmtu = tmp->phymtu;
357 	}
358 	else if (tmp->linkmtu < IPV6_MMTU || tmp->linkmtu > tmp->phymtu) {
359 		syslog(LOG_ERR,
360 		       "<%s> advertised link mtu must be between"
361 		       " least MTU and physical link MTU",
362 		       __FUNCTION__);
363 		exit(1);
364 	}
365 
366 	/* okey */
367 	tmp->next = ralist;
368 	ralist = tmp;
369 
370 	/* construct the sending packet */
371 	make_packet(tmp);
372 
373 	/* set timer */
374 	tmp->timer = rtadvd_add_timer(ra_timeout, ra_timer_update,
375 				      tmp, tmp);
376 	ra_timer_update((void *)tmp, &tmp->timer->tm);
377 	rtadvd_set_timer(&tmp->timer->tm, tmp->timer);
378 }
379 
380 static void
381 get_prefix(struct rainfo *rai)
382 {
383 	size_t len;
384 	u_char *buf, *lim, *next;
385 	u_char ntopbuf[INET6_ADDRSTRLEN];
386 
387 	if ((len = rtbuf_len()) < 0) {
388 		syslog(LOG_ERR,
389 		       "<%s> can't get buffer length for routing info",
390 		       __FUNCTION__);
391 		exit(1);
392 	}
393 	if ((buf = malloc(len)) == NULL) {
394 		syslog(LOG_ERR,
395 		       "<%s> can't allocate buffer", __FUNCTION__);
396 		exit(1);
397 	}
398 	if (get_rtinfo(buf, &len) < 0) {
399 		syslog(LOG_ERR,
400 		       "<%s> can't get routing inforamtion", __FUNCTION__);
401 		exit(1);
402 	}
403 
404 	lim = buf + len;
405 	next = get_next_msg(buf, lim, rai->ifindex, &len,
406 			    RTADV_TYPE2BITMASK(RTM_GET));
407 	while (next < lim) {
408 		struct prefix *pp;
409 		struct in6_addr *a;
410 
411 		/* allocate memory to store prefix info. */
412 		if ((pp = malloc(sizeof(*pp))) == NULL) {
413 			syslog(LOG_ERR,
414 			       "<%s> can't get allocate buffer for prefix",
415 			       __FUNCTION__);
416 			exit(1);
417 		}
418 		memset(pp, 0, sizeof(*pp));
419 
420 		/* set prefix and its length */
421 		a = get_addr(next);
422 		memcpy(&pp->prefix, a, sizeof(*a));
423 		if ((pp->prefixlen = get_prefixlen(next)) < 0) {
424 			syslog(LOG_ERR,
425 			       "<%s> failed to get prefixlen "
426 			       "or prefixl is invalid",
427 			       __FUNCTION__);
428 			exit(1);
429 		}
430 		syslog(LOG_DEBUG,
431 		       "<%s> add %s/%d to prefix list on %s",
432 		       __FUNCTION__,
433 		       inet_ntop(AF_INET6, a, ntopbuf, INET6_ADDRSTRLEN),
434 		       pp->prefixlen, rai->ifname);
435 
436 		/* set other fields with protocol defaults */
437 		pp->validlifetime = DEF_ADVVALIDLIFETIME;
438 		pp->preflifetime = DEF_ADVPREFERREDLIFETIME;
439 		pp->onlinkflg = 1;
440 		pp->autoconfflg = 1;
441 
442 		/* link into chain */
443 		insque(pp, &rai->prefix);
444 
445 		/* counter increment */
446 		rai->pfxs++;
447 
448 		/* forward pointer and get next prefix(if any) */
449 		next += len;
450 		next = get_next_msg(next, lim, rai->ifindex,
451 				    &len, RTADV_TYPE2BITMASK(RTM_GET));
452 	}
453 
454 	free(buf);
455 }
456 
457 static void
458 makeentry(buf, id, string, add)
459     char *buf, *string;
460     int id, add;
461 {
462 	strcpy(buf, string);
463 	if (add) {
464 		char *cp;
465 
466 		cp = (char *)index(buf, '\0');
467 		cp += sprintf(cp, "%d", id);
468 		*cp = '\0';
469 	}
470 }
471 
472 /*
473  * Add a prefix to the list of specified interface and reconstruct
474  * the outgoing packet.
475  * The prefix must not be in the list.
476  * XXX: other parameter of the prefix(e.g. lifetime) shoule be
477  * able to be specified.
478  */
479 static void
480 add_prefix(struct rainfo *rai, struct in6_prefixreq *ipr)
481 {
482 	struct prefix *prefix;
483 	u_char ntopbuf[INET6_ADDRSTRLEN];
484 
485 	if ((prefix = malloc(sizeof(*prefix))) == NULL) {
486 		syslog(LOG_ERR, "<%s> memory allocation failed",
487 		       __FUNCTION__);
488 		return;		/* XXX: error or exit? */
489 	}
490 	prefix->prefix = ipr->ipr_prefix.sin6_addr;
491 	prefix->prefixlen = ipr->ipr_plen;
492 	prefix->validlifetime = ipr->ipr_vltime;
493 	prefix->preflifetime = ipr->ipr_pltime;
494 	prefix->onlinkflg = ipr->ipr_raf_onlink;
495 	prefix->autoconfflg = ipr->ipr_raf_auto;
496 
497 	insque(prefix, &rai->prefix);
498 
499 	syslog(LOG_DEBUG, "<%s> new prefix %s/%d was added on %s",
500 	       __FUNCTION__, inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr,
501 				       ntopbuf, INET6_ADDRSTRLEN),
502 	       ipr->ipr_plen, rai->ifname);
503 
504 	/* free the previous packet */
505 	free(rai->ra_data);
506 	rai->ra_data = 0;
507 
508 	/* reconstruct the packet */
509 	rai->pfxs++;
510 	make_packet(rai);
511 
512 	/*
513 	 * reset the timer so that the new prefix will be advertised quickly.
514 	 */
515 	rai->initcounter = 0;
516 	ra_timer_update((void *)rai, &rai->timer->tm);
517 	rtadvd_set_timer(&rai->timer->tm, rai->timer);
518 }
519 
520 /*
521  * Delete a prefix to the list of specified interface and reconstruct
522  * the outgoing packet.
523  * The prefix must be in the list
524  */
525 void
526 delete_prefix(struct rainfo *rai, struct prefix *prefix)
527 {
528 	u_char ntopbuf[INET6_ADDRSTRLEN];
529 
530 	remque(prefix);
531 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was deleted on %s",
532 	       __FUNCTION__, inet_ntop(AF_INET6, &prefix->prefix,
533 				       ntopbuf, INET6_ADDRSTRLEN),
534 	       prefix->prefixlen, rai->ifname);
535 	free(prefix);
536 	rai->pfxs--;
537 	make_packet(rai);
538 }
539 
540 /*
541  * Try to get an in6_prefixreq contents for a prefix which matches
542  * ipr->ipr_prefix and ipr->ipr_plen and belongs to
543  * the interface whose name is ipr->ipr_name[].
544  */
545 static int
546 init_prefix(struct in6_prefixreq *ipr)
547 {
548 	int s;
549 
550 	if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
551 		syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__,
552 		       strerror(errno));
553 		exit(1);
554 	}
555 
556 	if (ioctl(s, SIOCGIFPREFIX_IN6, (caddr_t)ipr) < 0) {
557 		syslog(LOG_INFO, "<%s> ioctl:SIOCGIFPREFIX %s", __FUNCTION__,
558 		       strerror(errno));
559 
560 		ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
561 		ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
562 		ipr->ipr_raf_onlink = 1;
563 		ipr->ipr_raf_auto = 1;
564 		/* omit other field initialization */
565 	}
566 	else if (ipr->ipr_origin < PR_ORIG_RR) {
567 		u_char ntopbuf[INET6_ADDRSTRLEN];
568 
569 		syslog(LOG_WARNING, "<%s> Added prefix(%s)'s origin %d is"
570 		       "lower than PR_ORIG_RR(router renumbering)."
571 		       "This should not happen if I am router", __FUNCTION__,
572 		       inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf,
573 				 sizeof(ntopbuf)), ipr->ipr_origin);
574 		close(s);
575 		return 1;
576 	}
577 
578 	close(s);
579 	return 0;
580 }
581 
582 void
583 make_prefix(struct rainfo *rai, int ifindex, struct in6_addr *addr, int plen)
584 {
585 	struct in6_prefixreq ipr;
586 
587 	memset(&ipr, 0, sizeof(ipr));
588 	if (if_indextoname(ifindex, ipr.ipr_name) == NULL) {
589 		syslog(LOG_ERR, "<%s> Prefix added interface No.%d doesn't"
590 		       "exist. This should not happen! %s", __FUNCTION__,
591 		       ifindex, strerror(errno));
592 		exit(1);
593 	}
594 	ipr.ipr_prefix.sin6_len = sizeof(ipr.ipr_prefix);
595 	ipr.ipr_prefix.sin6_family = AF_INET6;
596 	ipr.ipr_prefix.sin6_addr = *addr;
597 	ipr.ipr_plen = plen;
598 
599 	if (init_prefix(&ipr))
600 		return; /* init failed by some error */
601 	add_prefix(rai, &ipr);
602 }
603 
604 void
605 make_packet(struct rainfo *rainfo)
606 {
607 	size_t packlen, lladdroptlen = 0;
608 	char *buf;
609 	struct nd_router_advert *ra;
610 	struct nd_opt_prefix_info *ndopt_pi;
611 	struct nd_opt_mtu *ndopt_mtu;
612 #ifdef MIP6
613 	struct nd_opt_advint *ndopt_advint;
614 	struct nd_opt_hai *ndopt_hai;
615 #endif
616 	struct prefix *pfx;
617 
618 	/* calculate total length */
619 	packlen = sizeof(struct nd_router_advert);
620 	if (rainfo->advlinkopt) {
621 		if ((lladdroptlen = lladdropt_length(rainfo->sdl)) == 0) {
622 			syslog(LOG_INFO,
623 			       "<%s> link-layer address option has"
624 			       " null length on %s."
625 			       " Treat as not included.",
626 			       __FUNCTION__, rainfo->ifname);
627 			rainfo->advlinkopt = 0;
628 		}
629 		packlen += lladdroptlen;
630 	}
631 	if (rainfo->pfxs)
632 		packlen += sizeof(struct nd_opt_prefix_info) * rainfo->pfxs;
633 	if (rainfo->linkmtu)
634 		packlen += sizeof(struct nd_opt_mtu);
635 #ifdef MIP6
636 	if (mobileip6 && rainfo->maxinterval)
637 		packlen += sizeof(struct nd_opt_advint);
638 	if (mobileip6 && rainfo->hatime)
639 		packlen += sizeof(struct nd_opt_hai);
640 #endif
641 
642 	/* allocate memory for the packet */
643 	if ((buf = malloc(packlen)) == NULL) {
644 		syslog(LOG_ERR,
645 		       "<%s> can't get enough memory for an RA packet",
646 		       __FUNCTION__);
647 		exit(1);
648 	}
649 	rainfo->ra_data = buf;
650 	/* XXX: what if packlen > 576? */
651 	rainfo->ra_datalen = packlen;
652 
653 	/*
654 	 * construct the packet
655 	 */
656 	ra = (struct nd_router_advert *)buf;
657 	ra->nd_ra_type = ND_ROUTER_ADVERT;
658 	ra->nd_ra_code = 0;
659 	ra->nd_ra_cksum = 0;
660 	ra->nd_ra_curhoplimit = (u_int8_t)(0xff & rainfo->hoplimit);
661 	ra->nd_ra_flags_reserved = 0;
662 	ra->nd_ra_flags_reserved |=
663 		rainfo->managedflg ? ND_RA_FLAG_MANAGED : 0;
664 	ra->nd_ra_flags_reserved |=
665 		rainfo->otherflg ? ND_RA_FLAG_OTHER : 0;
666 #ifdef MIP6
667 	ra->nd_ra_flags_reserved |=
668 		rainfo->haflg ? ND_RA_FLAG_HA : 0;
669 #endif
670 	ra->nd_ra_router_lifetime = htons(rainfo->lifetime);
671 	ra->nd_ra_reachable = htonl(rainfo->reachabletime);
672 	ra->nd_ra_retransmit = htonl(rainfo->retranstimer);
673 	buf += sizeof(*ra);
674 
675 	if (rainfo->advlinkopt) {
676 		lladdropt_fill(rainfo->sdl, (struct nd_opt_hdr *)buf);
677 		buf += lladdroptlen;
678 	}
679 
680 	if (rainfo->linkmtu) {
681 		ndopt_mtu = (struct nd_opt_mtu *)buf;
682 		ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU;
683 		ndopt_mtu->nd_opt_mtu_len = 1;
684 		ndopt_mtu->nd_opt_mtu_reserved = 0;
685 		ndopt_mtu->nd_opt_mtu_mtu = ntohl(rainfo->linkmtu);
686 		buf += sizeof(struct nd_opt_mtu);
687 	}
688 
689 #ifdef MIP6
690 	if (mobileip6 && rainfo->maxinterval) {
691 		ndopt_advint = (struct nd_opt_advint *)buf;
692 		ndopt_advint->nd_opt_int_type = ND_OPT_ADV_INTERVAL;
693 		ndopt_advint->nd_opt_int_len = 1;
694 		ndopt_advint->nd_opt_int_reserved = 0;
695 		ndopt_advint->nd_opt_int_interval = ntohl(rainfo->maxinterval *
696 							  1000);
697 		buf += sizeof(struct nd_opt_advint);
698 	}
699 #endif
700 
701 #ifdef MIP6
702 	if (rainfo->hatime) {
703 		ndopt_hai = (struct nd_opt_hai *)buf;
704 		ndopt_hai->nd_opt_hai_type = ND_OPT_HA_INFORMATION;
705 		ndopt_hai->nd_opt_hai_len = 1;
706 		ndopt_hai->nd_opt_hai_reserved = 0;
707 		ndopt_hai->nd_opt_hai_pref = ntohs(rainfo->hapref);
708 		ndopt_hai->nd_opt_hai_lifetime = ntohs(rainfo->hatime);
709 		buf += sizeof(struct nd_opt_hai);
710 	}
711 #endif
712 
713 	for (pfx = rainfo->prefix.next;
714 	     pfx != &rainfo->prefix; pfx = pfx->next) {
715 		ndopt_pi = (struct nd_opt_prefix_info *)buf;
716 		ndopt_pi->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
717 		ndopt_pi->nd_opt_pi_len = 4;
718 		ndopt_pi->nd_opt_pi_prefix_len = pfx->prefixlen;
719 		ndopt_pi->nd_opt_pi_flags_reserved = 0;
720 		if (pfx->onlinkflg)
721 			ndopt_pi->nd_opt_pi_flags_reserved |=
722 				ND_OPT_PI_FLAG_ONLINK;
723 		if (pfx->autoconfflg)
724 			ndopt_pi->nd_opt_pi_flags_reserved |=
725 				ND_OPT_PI_FLAG_AUTO;
726 #ifdef MIP6
727 		if (pfx->routeraddr)
728 			ndopt_pi->nd_opt_pi_flags_reserved |=
729 				ND_OPT_PI_FLAG_RTADDR;
730 #endif
731 		ndopt_pi->nd_opt_pi_valid_time = ntohl(pfx->validlifetime);
732 		ndopt_pi->nd_opt_pi_preferred_time =
733 			ntohl(pfx->preflifetime);
734 		ndopt_pi->nd_opt_pi_reserved2 = 0;
735 		ndopt_pi->nd_opt_pi_prefix = pfx->prefix;
736 
737 		buf += sizeof(struct nd_opt_prefix_info);
738 	}
739 
740 	return;
741 }
742