xref: /freebsd/usr.sbin/rtadvd/config.c (revision 1d66272a85cde1c8a69c58f4b5dd649babd6eca6)
1 /*	$KAME: config.c,v 1.11 2000/05/16 13:34:13 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  * $FreeBSD$
32  */
33 
34 #include <sys/param.h>
35 #include <sys/ioctl.h>
36 #include <sys/socket.h>
37 #include <sys/time.h>
38 
39 #include <net/if.h>
40 #if defined(__FreeBSD__) && __FreeBSD__ >= 3
41 #include <net/if_var.h>
42 #endif /* __FreeBSD__ >= 3 */
43 #include <net/route.h>
44 #include <net/if_dl.h>
45 
46 #include <netinet/in.h>
47 #include <netinet/in_var.h>
48 #include <netinet/ip6.h>
49 #include <netinet6/ip6_var.h>
50 #include <netinet/icmp6.h>
51 #ifdef MIP6
52 #include <netinet6/mip6.h>
53 #endif
54 
55 #include <arpa/inet.h>
56 
57 #include <stdio.h>
58 #include <syslog.h>
59 #include <errno.h>
60 #include <string.h>
61 #include <stdlib.h>
62 #if defined(__NetBSD__) || defined(__OpenBSD__)
63 #include <search.h>
64 #endif
65 #include <unistd.h>
66 
67 #include "rtadvd.h"
68 #include "advcap.h"
69 #include "timer.h"
70 #include "if.h"
71 #include "config.h"
72 
73 static void makeentry __P((char *, int, char *, int));
74 static void get_prefix __P((struct rainfo *));
75 
76 extern struct rainfo *ralist;
77 
78 void
79 getconfig(intface)
80 	char *intface;
81 {
82 	int stat, pfxs, i;
83 	char tbuf[BUFSIZ];
84 	struct rainfo *tmp;
85 	long val;
86 	char buf[BUFSIZ];
87 	char *bp = buf;
88 	char *addr;
89 
90 #define MUSTHAVE(var, cap)	\
91     do {								\
92 	int t;								\
93 	if ((t = agetnum(cap)) < 0) {					\
94 		fprintf(stderr, "rtadvd: need %s for interface %s\n",	\
95 			cap, intface);					\
96 		exit(1);						\
97 	}								\
98 	var = t;							\
99      } while (0)
100 #define MAYHAVE(var, cap, def)	\
101      do {								\
102 	if ((var = agetnum(cap)) < 0)					\
103 		var = def;						\
104      } while (0)
105 
106 	if ((stat = agetent(tbuf, intface)) <= 0) {
107 		memset(tbuf, 0, sizeof(tbuf));
108 		syslog(LOG_INFO,
109 		       "<%s> %s isn't defined in the configuration file"
110 		       " or the configuration file doesn't exist."
111 		       " Treat it as default",
112 		        __FUNCTION__, intface);
113 	}
114 
115 	tmp = (struct rainfo *)malloc(sizeof(*ralist));
116 	memset(tmp, 0, sizeof(*tmp));
117 	tmp->prefix.next = tmp->prefix.prev = &tmp->prefix;
118 
119 	/* get interface information */
120 	if (agetflag("nolladdr"))
121 		tmp->advlinkopt = 0;
122 	else
123 		tmp->advlinkopt = 1;
124 	if (tmp->advlinkopt) {
125 		if ((tmp->sdl = if_nametosdl(intface)) == NULL) {
126 			syslog(LOG_ERR,
127 			       "<%s> can't get information of %s",
128 			       __FUNCTION__, intface);
129 			exit(1);
130 		}
131 		tmp->ifindex = tmp->sdl->sdl_index;
132 	} else
133 		tmp->ifindex = if_nametoindex(intface);
134 	strncpy(tmp->ifname, intface, sizeof(tmp->ifname));
135 	if ((tmp->phymtu = if_getmtu(intface)) == 0) {
136 		tmp->phymtu = IPV6_MMTU;
137 		syslog(LOG_WARNING,
138 		       "<%s> can't get interface mtu of %s. Treat as %d",
139 		       __FUNCTION__, intface, IPV6_MMTU);
140 	}
141 
142 	/*
143 	 * set router configuration variables.
144 	 */
145 	MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL);
146 	if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) {
147 		syslog(LOG_ERR,
148 		       "<%s> maxinterval must be between %e and %u",
149 		       __FUNCTION__, MIN_MAXINTERVAL, MAX_MAXINTERVAL);
150 		exit(1);
151 	}
152 	tmp->maxinterval = (u_int)val;
153 	MAYHAVE(val, "mininterval", tmp->maxinterval/3);
154 	if (val < MIN_MININTERVAL || val > (tmp->maxinterval * 3) / 4) {
155 		syslog(LOG_ERR,
156 		       "<%s> mininterval must be between %e and %d",
157 		       __FUNCTION__,
158 		       MIN_MININTERVAL,
159 		       (tmp->maxinterval * 3) / 4);
160 		exit(1);
161 	}
162 	tmp->mininterval = (u_int)val;
163 
164 	MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT);
165 	tmp->hoplimit = val & 0xff;
166 
167 	MAYHAVE(val, "raflags", 0);
168 	tmp->managedflg= val & ND_RA_FLAG_MANAGED;
169 	tmp->otherflg = val & ND_RA_FLAG_OTHER;
170 #ifdef MIP6
171 	if (mobileip6)
172 		tmp->haflg = val & ND_RA_FLAG_HA;
173 #endif
174 
175 	MAYHAVE(val, "rltime", tmp->maxinterval * 3);
176 	if (val && (val < tmp->maxinterval || val > MAXROUTERLIFETIME)) {
177 		syslog(LOG_ERR,
178 		       "<%s> router lifetime on %s must be 0 or"
179 		       " between %d and %d",
180 		       __FUNCTION__, intface,
181 		       tmp->maxinterval, MAXROUTERLIFETIME);
182 		exit(1);
183 	}
184 	tmp->lifetime = val & 0xffff;
185 
186 	MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME);
187 	if (val > MAXREACHABLETIME) {
188 		syslog(LOG_ERR,
189 		       "<%s> reachable time must be no greater than %d",
190 		       __FUNCTION__, MAXREACHABLETIME);
191 		exit(1);
192 	}
193 	tmp->reachabletime = (u_int32_t)val;
194 
195 	MAYHAVE(val, "retrans", DEF_ADVRETRANSTIMER);
196 	if (val < 0 || val > 0xffffffff) {
197 		syslog(LOG_ERR,
198 		       "<%s> retrans time out of range", __FUNCTION__);
199 		exit(1);
200 	}
201 	tmp->retranstimer = (u_int32_t)val;
202 
203 #ifdef MIP6
204 	if (!mobileip6)
205 #else
206 	if (1)
207 #endif
208 	{
209 		if (agetstr("hapref", &bp) || agetstr("hatime", &bp)) {
210 			syslog(LOG_ERR,
211 			       "<%s> mobile-ip6 configuration without "
212 			       "proper command line option",
213 			       __FUNCTION__);
214 			exit(1);
215 		}
216 	}
217 #ifdef MIP6
218 	else {
219 		tmp->hapref = 0;
220 		if ((val = agetnum("hapref")) >= 0)
221 			tmp->hapref = (int16_t)val;
222 		if (tmp->hapref != 0) {
223 			tmp->hatime = 0;
224 			MUSTHAVE(val, "hatime");
225 			tmp->hatime = (u_int16_t)val;
226 			if (tmp->hatime <= 0) {
227 				syslog(LOG_ERR,
228 				       "<%s> home agent lifetime must be greater than 0",
229 				       __FUNCTION__);
230 				exit(1);
231 			}
232 		}
233 	}
234 #endif
235 
236 	/* prefix information */
237 	if ((pfxs = agetnum("addrs")) < 0) {
238 		/* auto configure prefix information */
239 		if (agetstr("addr", &bp) || agetstr("addr1", &bp)) {
240 			syslog(LOG_ERR,
241 			       "<%s> conflicting prefix configuration for %s: "
242 			       "automatic and manual config at the same time",
243 			       __FUNCTION__, intface);
244 			exit(1);
245 		}
246 		get_prefix(tmp);
247 	}
248 	else {
249 		tmp->pfxs = pfxs;
250 		for (i = 0; i < pfxs; i++) {
251 			struct prefix *pfx;
252 			char entbuf[256];
253 			int added = (pfxs > 1) ? 1 : 0;
254 
255 			/* allocate memory to store prefix information */
256 			if ((pfx = malloc(sizeof(struct prefix))) == NULL) {
257 				syslog(LOG_ERR,
258 				       "<%s> can't allocate enough memory",
259 				       __FUNCTION__);
260 				exit(1);
261 			}
262 			/* link into chain */
263 			insque(pfx, &tmp->prefix);
264 
265 			pfx->origin = PREFIX_FROM_CONFIG;
266 
267 			makeentry(entbuf, i, "prefixlen", added);
268 			MAYHAVE(val, entbuf, 64);
269 			if (val < 0 || val > 128) {
270 				syslog(LOG_ERR,
271 				       "<%s> prefixlen out of range",
272 				       __FUNCTION__);
273 				exit(1);
274 			}
275 			pfx->prefixlen = (int)val;
276 
277 			makeentry(entbuf, i, "pinfoflags", added);
278 #ifdef MIP6
279 			if (mobileip6)
280 			{
281 				MAYHAVE(val, entbuf,
282 				    (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO|
283 					 ND_OPT_PI_FLAG_RTADDR));
284 			} else
285 #endif
286 			{
287 				MAYHAVE(val, entbuf,
288 				    (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO));
289 			}
290 			pfx->onlinkflg = val & ND_OPT_PI_FLAG_ONLINK;
291 			pfx->autoconfflg = val & ND_OPT_PI_FLAG_AUTO;
292 #ifdef MIP6
293 			if (mobileip6)
294 				pfx->routeraddr = val & ND_OPT_PI_FLAG_RTADDR;
295 #endif
296 
297 			makeentry(entbuf, i, "vltime", added);
298 			MAYHAVE(val, entbuf, DEF_ADVVALIDLIFETIME);
299 			if (val < 0 || val > 0xffffffff) {
300 				syslog(LOG_ERR,
301 				       "<%s> vltime out of range",
302 				       __FUNCTION__);
303 				exit(1);
304 			}
305 			pfx->validlifetime = (u_int32_t)val;
306 
307 			makeentry(entbuf, i, "pltime", added);
308 			MAYHAVE(val, entbuf, DEF_ADVPREFERREDLIFETIME);
309 			if (val < 0 || val > 0xffffffff) {
310 				syslog(LOG_ERR,
311 				       "<%s> pltime out of range",
312 				       __FUNCTION__);
313 				exit(1);
314 			}
315 			pfx->preflifetime = (u_int32_t)val;
316 
317 			makeentry(entbuf, i, "addr", added);
318 			addr = (char *)agetstr(entbuf, &bp);
319 			if (addr == NULL) {
320 				syslog(LOG_ERR,
321 				       "<%s> need %s as an prefix for "
322 				       "interface %s",
323 				       __FUNCTION__, entbuf, intface);
324 				exit(1);
325 			}
326 			if (inet_pton(AF_INET6, addr,
327 				      &pfx->prefix) != 1) {
328 				syslog(LOG_ERR,
329 				       "<%s> inet_pton failed for %s",
330 				       __FUNCTION__, addr);
331 				exit(1);
332 			}
333 			if (IN6_IS_ADDR_MULTICAST(&pfx->prefix)) {
334 				syslog(LOG_ERR,
335 				       "<%s> multicast prefix(%s) must "
336 				       "not be advertised (IF=%s)",
337 				       __FUNCTION__, addr, intface);
338 				exit(1);
339 			}
340 			if (IN6_IS_ADDR_LINKLOCAL(&pfx->prefix))
341 				syslog(LOG_NOTICE,
342 				       "<%s> link-local prefix(%s) will be"
343 				       " advertised on %s",
344 				       __FUNCTION__, addr, intface);
345 		}
346 	}
347 
348 	MAYHAVE(val, "mtu", 0);
349 	if (val < 0 || val > 0xffffffff) {
350 		syslog(LOG_ERR,
351 		       "<%s> mtu out of range", __FUNCTION__);
352 		exit(1);
353 	}
354 	tmp->linkmtu = (u_int32_t)val;
355 	if (tmp->linkmtu == 0) {
356 		char *mtustr;
357 
358 		if ((mtustr = (char *)agetstr("mtu", &bp)) &&
359 		    strcmp(mtustr, "auto") == 0)
360 			tmp->linkmtu = tmp->phymtu;
361 	}
362 	else if (tmp->linkmtu < IPV6_MMTU || tmp->linkmtu > tmp->phymtu) {
363 		syslog(LOG_ERR,
364 		       "<%s> advertised link mtu must be between"
365 		       " least MTU and physical link MTU",
366 		       __FUNCTION__);
367 		exit(1);
368 	}
369 
370 	/* okey */
371 	tmp->next = ralist;
372 	ralist = tmp;
373 
374 	/* construct the sending packet */
375 	make_packet(tmp);
376 
377 	/* set timer */
378 	tmp->timer = rtadvd_add_timer(ra_timeout, ra_timer_update,
379 				      tmp, tmp);
380 	ra_timer_update((void *)tmp, &tmp->timer->tm);
381 	rtadvd_set_timer(&tmp->timer->tm, tmp->timer);
382 }
383 
384 static void
385 get_prefix(struct rainfo *rai)
386 {
387 	size_t len;
388 	u_char *buf, *lim, *next;
389 	u_char ntopbuf[INET6_ADDRSTRLEN];
390 
391 	if ((len = rtbuf_len()) < 0) {
392 		syslog(LOG_ERR,
393 		       "<%s> can't get buffer length for routing info",
394 		       __FUNCTION__);
395 		exit(1);
396 	}
397 	if ((buf = malloc(len)) == NULL) {
398 		syslog(LOG_ERR,
399 		       "<%s> can't allocate buffer", __FUNCTION__);
400 		exit(1);
401 	}
402 	if (get_rtinfo(buf, &len) < 0) {
403 		syslog(LOG_ERR,
404 		       "<%s> can't get routing inforamtion", __FUNCTION__);
405 		exit(1);
406 	}
407 
408 	lim = buf + len;
409 	next = get_next_msg(buf, lim, rai->ifindex, &len,
410 			    RTADV_TYPE2BITMASK(RTM_GET));
411 	while (next < lim) {
412 		struct prefix *pp;
413 		struct in6_addr *a;
414 
415 		/* allocate memory to store prefix info. */
416 		if ((pp = malloc(sizeof(*pp))) == NULL) {
417 			syslog(LOG_ERR,
418 			       "<%s> can't get allocate buffer for prefix",
419 			       __FUNCTION__);
420 			exit(1);
421 		}
422 		memset(pp, 0, sizeof(*pp));
423 
424 		/* set prefix and its length */
425 		a = get_addr(next);
426 		memcpy(&pp->prefix, a, sizeof(*a));
427 		if ((pp->prefixlen = get_prefixlen(next)) < 0) {
428 			syslog(LOG_ERR,
429 			       "<%s> failed to get prefixlen "
430 			       "or prefixl is invalid",
431 			       __FUNCTION__);
432 			exit(1);
433 		}
434 		syslog(LOG_DEBUG,
435 		       "<%s> add %s/%d to prefix list on %s",
436 		       __FUNCTION__,
437 		       inet_ntop(AF_INET6, a, ntopbuf, INET6_ADDRSTRLEN),
438 		       pp->prefixlen, rai->ifname);
439 
440 		/* set other fields with protocol defaults */
441 		pp->validlifetime = DEF_ADVVALIDLIFETIME;
442 		pp->preflifetime = DEF_ADVPREFERREDLIFETIME;
443 		pp->onlinkflg = 1;
444 		pp->autoconfflg = 1;
445 		pp->origin = PREFIX_FROM_KERNEL;
446 
447 		/* link into chain */
448 		insque(pp, &rai->prefix);
449 
450 		/* counter increment */
451 		rai->pfxs++;
452 
453 		/* forward pointer and get next prefix(if any) */
454 		next += len;
455 		next = get_next_msg(next, lim, rai->ifindex,
456 				    &len, RTADV_TYPE2BITMASK(RTM_GET));
457 	}
458 
459 	free(buf);
460 }
461 
462 static void
463 makeentry(buf, id, string, add)
464     char *buf, *string;
465     int id, add;
466 {
467 	strcpy(buf, string);
468 	if (add) {
469 		char *cp;
470 
471 		cp = (char *)index(buf, '\0');
472 		cp += sprintf(cp, "%d", id);
473 		*cp = '\0';
474 	}
475 }
476 
477 /*
478  * Add a prefix to the list of specified interface and reconstruct
479  * the outgoing packet.
480  * The prefix must not be in the list.
481  * XXX: other parameter of the prefix(e.g. lifetime) shoule be
482  * able to be specified.
483  */
484 static void
485 add_prefix(struct rainfo *rai, struct in6_prefixreq *ipr)
486 {
487 	struct prefix *prefix;
488 	u_char ntopbuf[INET6_ADDRSTRLEN];
489 
490 	if ((prefix = malloc(sizeof(*prefix))) == NULL) {
491 		syslog(LOG_ERR, "<%s> memory allocation failed",
492 		       __FUNCTION__);
493 		return;		/* XXX: error or exit? */
494 	}
495 	prefix->prefix = ipr->ipr_prefix.sin6_addr;
496 	prefix->prefixlen = ipr->ipr_plen;
497 	prefix->validlifetime = ipr->ipr_vltime;
498 	prefix->preflifetime = ipr->ipr_pltime;
499 	prefix->onlinkflg = ipr->ipr_raf_onlink;
500 	prefix->autoconfflg = ipr->ipr_raf_auto;
501 	prefix->origin = PREFIX_FROM_DYNAMIC;
502 
503 	insque(prefix, &rai->prefix);
504 
505 	syslog(LOG_DEBUG, "<%s> new prefix %s/%d was added on %s",
506 	       __FUNCTION__, inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr,
507 				       ntopbuf, INET6_ADDRSTRLEN),
508 	       ipr->ipr_plen, rai->ifname);
509 
510 	/* free the previous packet */
511 	free(rai->ra_data);
512 	rai->ra_data = 0;
513 
514 	/* reconstruct the packet */
515 	rai->pfxs++;
516 	make_packet(rai);
517 
518 	/*
519 	 * reset the timer so that the new prefix will be advertised quickly.
520 	 */
521 	rai->initcounter = 0;
522 	ra_timer_update((void *)rai, &rai->timer->tm);
523 	rtadvd_set_timer(&rai->timer->tm, rai->timer);
524 }
525 
526 /*
527  * Delete a prefix to the list of specified interface and reconstruct
528  * the outgoing packet.
529  * The prefix must be in the list.
530  */
531 void
532 delete_prefix(struct rainfo *rai, struct prefix *prefix)
533 {
534 	u_char ntopbuf[INET6_ADDRSTRLEN];
535 
536 	remque(prefix);
537 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was deleted on %s",
538 	       __FUNCTION__, inet_ntop(AF_INET6, &prefix->prefix,
539 				       ntopbuf, INET6_ADDRSTRLEN),
540 	       prefix->prefixlen, rai->ifname);
541 	free(prefix);
542 	rai->pfxs--;
543 	make_packet(rai);
544 }
545 
546 /*
547  * Try to get an in6_prefixreq contents for a prefix which matches
548  * ipr->ipr_prefix and ipr->ipr_plen and belongs to
549  * the interface whose name is ipr->ipr_name[].
550  */
551 static int
552 init_prefix(struct in6_prefixreq *ipr)
553 {
554 	int s;
555 
556 	if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
557 		syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__,
558 		       strerror(errno));
559 		exit(1);
560 	}
561 
562 	if (ioctl(s, SIOCGIFPREFIX_IN6, (caddr_t)ipr) < 0) {
563 		syslog(LOG_INFO, "<%s> ioctl:SIOCGIFPREFIX %s", __FUNCTION__,
564 		       strerror(errno));
565 
566 		ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
567 		ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
568 		ipr->ipr_raf_onlink = 1;
569 		ipr->ipr_raf_auto = 1;
570 		/* omit other field initialization */
571 	}
572 	else if (ipr->ipr_origin < PR_ORIG_RR) {
573 		u_char ntopbuf[INET6_ADDRSTRLEN];
574 
575 		syslog(LOG_WARNING, "<%s> Added prefix(%s)'s origin %d is"
576 		       "lower than PR_ORIG_RR(router renumbering)."
577 		       "This should not happen if I am router", __FUNCTION__,
578 		       inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf,
579 				 sizeof(ntopbuf)), ipr->ipr_origin);
580 		close(s);
581 		return 1;
582 	}
583 
584 	close(s);
585 	return 0;
586 }
587 
588 void
589 make_prefix(struct rainfo *rai, int ifindex, struct in6_addr *addr, int plen)
590 {
591 	struct in6_prefixreq ipr;
592 
593 	memset(&ipr, 0, sizeof(ipr));
594 	if (if_indextoname(ifindex, ipr.ipr_name) == NULL) {
595 		syslog(LOG_ERR, "<%s> Prefix added interface No.%d doesn't"
596 		       "exist. This should not happen! %s", __FUNCTION__,
597 		       ifindex, strerror(errno));
598 		exit(1);
599 	}
600 	ipr.ipr_prefix.sin6_len = sizeof(ipr.ipr_prefix);
601 	ipr.ipr_prefix.sin6_family = AF_INET6;
602 	ipr.ipr_prefix.sin6_addr = *addr;
603 	ipr.ipr_plen = plen;
604 
605 	if (init_prefix(&ipr))
606 		return; /* init failed by some error */
607 	add_prefix(rai, &ipr);
608 }
609 
610 void
611 make_packet(struct rainfo *rainfo)
612 {
613 	size_t packlen, lladdroptlen = 0;
614 	char *buf;
615 	struct nd_router_advert *ra;
616 	struct nd_opt_prefix_info *ndopt_pi;
617 	struct nd_opt_mtu *ndopt_mtu;
618 #ifdef MIP6
619 	struct nd_opt_advint *ndopt_advint;
620 	struct nd_opt_hai *ndopt_hai;
621 #endif
622 	struct prefix *pfx;
623 
624 	/* calculate total length */
625 	packlen = sizeof(struct nd_router_advert);
626 	if (rainfo->advlinkopt) {
627 		if ((lladdroptlen = lladdropt_length(rainfo->sdl)) == 0) {
628 			syslog(LOG_INFO,
629 			       "<%s> link-layer address option has"
630 			       " null length on %s."
631 			       " Treat as not included.",
632 			       __FUNCTION__, rainfo->ifname);
633 			rainfo->advlinkopt = 0;
634 		}
635 		packlen += lladdroptlen;
636 	}
637 	if (rainfo->pfxs)
638 		packlen += sizeof(struct nd_opt_prefix_info) * rainfo->pfxs;
639 	if (rainfo->linkmtu)
640 		packlen += sizeof(struct nd_opt_mtu);
641 #ifdef MIP6
642 	if (mobileip6 && rainfo->maxinterval)
643 		packlen += sizeof(struct nd_opt_advint);
644 	if (mobileip6 && rainfo->hatime)
645 		packlen += sizeof(struct nd_opt_hai);
646 #endif
647 
648 	/* allocate memory for the packet */
649 	if ((buf = malloc(packlen)) == NULL) {
650 		syslog(LOG_ERR,
651 		       "<%s> can't get enough memory for an RA packet",
652 		       __FUNCTION__);
653 		exit(1);
654 	}
655 	rainfo->ra_data = buf;
656 	/* XXX: what if packlen > 576? */
657 	rainfo->ra_datalen = packlen;
658 
659 	/*
660 	 * construct the packet
661 	 */
662 	ra = (struct nd_router_advert *)buf;
663 	ra->nd_ra_type = ND_ROUTER_ADVERT;
664 	ra->nd_ra_code = 0;
665 	ra->nd_ra_cksum = 0;
666 	ra->nd_ra_curhoplimit = (u_int8_t)(0xff & rainfo->hoplimit);
667 	ra->nd_ra_flags_reserved = 0;
668 	ra->nd_ra_flags_reserved |=
669 		rainfo->managedflg ? ND_RA_FLAG_MANAGED : 0;
670 	ra->nd_ra_flags_reserved |=
671 		rainfo->otherflg ? ND_RA_FLAG_OTHER : 0;
672 #ifdef MIP6
673 	ra->nd_ra_flags_reserved |=
674 		rainfo->haflg ? ND_RA_FLAG_HA : 0;
675 #endif
676 	ra->nd_ra_router_lifetime = htons(rainfo->lifetime);
677 	ra->nd_ra_reachable = htonl(rainfo->reachabletime);
678 	ra->nd_ra_retransmit = htonl(rainfo->retranstimer);
679 	buf += sizeof(*ra);
680 
681 	if (rainfo->advlinkopt) {
682 		lladdropt_fill(rainfo->sdl, (struct nd_opt_hdr *)buf);
683 		buf += lladdroptlen;
684 	}
685 
686 	if (rainfo->linkmtu) {
687 		ndopt_mtu = (struct nd_opt_mtu *)buf;
688 		ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU;
689 		ndopt_mtu->nd_opt_mtu_len = 1;
690 		ndopt_mtu->nd_opt_mtu_reserved = 0;
691 		ndopt_mtu->nd_opt_mtu_mtu = ntohl(rainfo->linkmtu);
692 		buf += sizeof(struct nd_opt_mtu);
693 	}
694 
695 #ifdef MIP6
696 	if (mobileip6 && rainfo->maxinterval) {
697 		ndopt_advint = (struct nd_opt_advint *)buf;
698 		ndopt_advint->nd_opt_int_type = ND_OPT_ADV_INTERVAL;
699 		ndopt_advint->nd_opt_int_len = 1;
700 		ndopt_advint->nd_opt_int_reserved = 0;
701 		ndopt_advint->nd_opt_int_interval = ntohl(rainfo->maxinterval *
702 							  1000);
703 		buf += sizeof(struct nd_opt_advint);
704 	}
705 #endif
706 
707 #ifdef MIP6
708 	if (rainfo->hatime) {
709 		ndopt_hai = (struct nd_opt_hai *)buf;
710 		ndopt_hai->nd_opt_hai_type = ND_OPT_HA_INFORMATION;
711 		ndopt_hai->nd_opt_hai_len = 1;
712 		ndopt_hai->nd_opt_hai_reserved = 0;
713 		ndopt_hai->nd_opt_hai_pref = ntohs(rainfo->hapref);
714 		ndopt_hai->nd_opt_hai_lifetime = ntohs(rainfo->hatime);
715 		buf += sizeof(struct nd_opt_hai);
716 	}
717 #endif
718 
719 	for (pfx = rainfo->prefix.next;
720 	     pfx != &rainfo->prefix; pfx = pfx->next) {
721 		ndopt_pi = (struct nd_opt_prefix_info *)buf;
722 		ndopt_pi->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
723 		ndopt_pi->nd_opt_pi_len = 4;
724 		ndopt_pi->nd_opt_pi_prefix_len = pfx->prefixlen;
725 		ndopt_pi->nd_opt_pi_flags_reserved = 0;
726 		if (pfx->onlinkflg)
727 			ndopt_pi->nd_opt_pi_flags_reserved |=
728 				ND_OPT_PI_FLAG_ONLINK;
729 		if (pfx->autoconfflg)
730 			ndopt_pi->nd_opt_pi_flags_reserved |=
731 				ND_OPT_PI_FLAG_AUTO;
732 #ifdef MIP6
733 		if (pfx->routeraddr)
734 			ndopt_pi->nd_opt_pi_flags_reserved |=
735 				ND_OPT_PI_FLAG_RTADDR;
736 #endif
737 		ndopt_pi->nd_opt_pi_valid_time = ntohl(pfx->validlifetime);
738 		ndopt_pi->nd_opt_pi_preferred_time =
739 			ntohl(pfx->preflifetime);
740 		ndopt_pi->nd_opt_pi_reserved2 = 0;
741 		ndopt_pi->nd_opt_pi_prefix = pfx->prefix;
742 
743 		buf += sizeof(struct nd_opt_prefix_info);
744 	}
745 
746 	return;
747 }
748