xref: /freebsd/usr.sbin/rtadvd/config.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*	$FreeBSD$	*/
2 /*	$KAME: config.c,v 1.84 2003/08/05 12:34:23 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 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/ioctl.h>
35 #include <sys/socket.h>
36 #include <sys/time.h>
37 #include <sys/sysctl.h>
38 
39 #include <net/if.h>
40 #include <net/if_var.h>
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 
50 #include <arpa/inet.h>
51 
52 #include <stdio.h>
53 #include <syslog.h>
54 #include <errno.h>
55 #include <string.h>
56 #include <stdlib.h>
57 #include <unistd.h>
58 #include <ifaddrs.h>
59 
60 #include "rtadvd.h"
61 #include "advcap.h"
62 #include "timer.h"
63 #include "if.h"
64 #include "config.h"
65 
66 static time_t prefix_timo = (60 * 120);	/* 2 hours.
67 					 * XXX: should be configurable. */
68 extern struct rainfo *ralist;
69 
70 static struct rtadvd_timer *prefix_timeout __P((void *));
71 static void makeentry __P((char *, size_t, int, char *));
72 static int getinet6sysctl __P((int));
73 
74 void
75 getconfig(intface)
76 	char *intface;
77 {
78 	int stat, i;
79 	char tbuf[BUFSIZ];
80 	struct rainfo *tmp;
81 	long val;
82 	int64_t val64;
83 	char buf[BUFSIZ];
84 	char *bp = buf;
85 	char *addr, *flagstr;
86 	static int forwarding = -1;
87 
88 #define MUSTHAVE(var, cap)	\
89     do {								\
90 	int64_t 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 		        __func__, intface);
111 	}
112 
113 	tmp = (struct rainfo *)malloc(sizeof(*ralist));
114 	if (tmp == NULL) {
115 		syslog(LOG_INFO, "<%s> %s: can't allocate enough memory",
116 		    __func__, intface);
117 		exit(1);
118 	}
119 	memset(tmp, 0, sizeof(*tmp));
120 	tmp->prefix.next = tmp->prefix.prev = &tmp->prefix;
121 #ifdef ROUTEINFO
122 	tmp->route.next = tmp->route.prev = &tmp->route;
123 #endif
124 
125 	/* check if we are allowed to forward packets (if not determined) */
126 	if (forwarding < 0) {
127 		if ((forwarding = getinet6sysctl(IPV6CTL_FORWARDING)) < 0)
128 			exit(1);
129 	}
130 
131 	/* get interface information */
132 	if (agetflag("nolladdr"))
133 		tmp->advlinkopt = 0;
134 	else
135 		tmp->advlinkopt = 1;
136 	if (tmp->advlinkopt) {
137 		if ((tmp->sdl = if_nametosdl(intface)) == NULL) {
138 			syslog(LOG_ERR,
139 			       "<%s> can't get information of %s",
140 			       __func__, intface);
141 			exit(1);
142 		}
143 		tmp->ifindex = tmp->sdl->sdl_index;
144 	} else
145 		tmp->ifindex = if_nametoindex(intface);
146 	strncpy(tmp->ifname, intface, sizeof(tmp->ifname));
147 	if ((tmp->phymtu = if_getmtu(intface)) == 0) {
148 		tmp->phymtu = IPV6_MMTU;
149 		syslog(LOG_WARNING,
150 		       "<%s> can't get interface mtu of %s. Treat as %d",
151 		       __func__, intface, IPV6_MMTU);
152 	}
153 
154 	/*
155 	 * set router configuration variables.
156 	 */
157 	MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL);
158 	if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) {
159 		syslog(LOG_ERR,
160 		       "<%s> maxinterval (%ld) on %s is invalid "
161 		       "(must be between %u and %u)", __func__, val,
162 		       intface, MIN_MAXINTERVAL, MAX_MAXINTERVAL);
163 		exit(1);
164 	}
165 	tmp->maxinterval = (u_int)val;
166 	MAYHAVE(val, "mininterval", tmp->maxinterval/3);
167 	if (val < MIN_MININTERVAL || val > (tmp->maxinterval * 3) / 4) {
168 		syslog(LOG_ERR,
169 		       "<%s> mininterval (%ld) on %s is invalid "
170 		       "(must be between %d and %d)",
171 		       __func__, val, intface, MIN_MININTERVAL,
172 		       (tmp->maxinterval * 3) / 4);
173 		exit(1);
174 	}
175 	tmp->mininterval = (u_int)val;
176 
177 	MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT);
178 	tmp->hoplimit = val & 0xff;
179 
180 	if ((flagstr = (char *)agetstr("raflags", &bp))) {
181 		val = 0;
182 		if (strchr(flagstr, 'm'))
183 			val |= ND_RA_FLAG_MANAGED;
184 		if (strchr(flagstr, 'o'))
185 			val |= ND_RA_FLAG_OTHER;
186 		if (strchr(flagstr, 'h'))
187 			val |= ND_RA_FLAG_RTPREF_HIGH;
188 		if (strchr(flagstr, 'l')) {
189 			if ((val & ND_RA_FLAG_RTPREF_HIGH)) {
190 				syslog(LOG_ERR, "<%s> the \'h\' and \'l\'"
191 				    " router flags are exclusive", __func__);
192 				exit(1);
193 			}
194 			val |= ND_RA_FLAG_RTPREF_LOW;
195 		}
196 	} else {
197 		MAYHAVE(val, "raflags", 0);
198 	}
199 	tmp->managedflg = val & ND_RA_FLAG_MANAGED;
200 	tmp->otherflg = val & ND_RA_FLAG_OTHER;
201 #ifndef ND_RA_FLAG_RTPREF_MASK
202 #define ND_RA_FLAG_RTPREF_MASK	0x18 /* 00011000 */
203 #define ND_RA_FLAG_RTPREF_RSV	0x10 /* 00010000 */
204 #endif
205 	tmp->rtpref = val & ND_RA_FLAG_RTPREF_MASK;
206 	if (tmp->rtpref == ND_RA_FLAG_RTPREF_RSV) {
207 		syslog(LOG_ERR, "<%s> invalid router preference (%02x) on %s",
208 		       __func__, tmp->rtpref, intface);
209 		exit(1);
210 	}
211 
212 	MAYHAVE(val, "rltime", tmp->maxinterval * 3);
213 	if (val && (val < tmp->maxinterval || val > MAXROUTERLIFETIME)) {
214 		syslog(LOG_ERR,
215 		       "<%s> router lifetime (%ld) on %s is invalid "
216 		       "(must be 0 or between %d and %d)",
217 		       __func__, val, intface,
218 		       tmp->maxinterval,
219 		       MAXROUTERLIFETIME);
220 		exit(1);
221 	}
222 	/*
223 	 * Basically, hosts MUST NOT send Router Advertisement messages at any
224 	 * time (RFC 2461, Section 6.2.3). However, it would sometimes be
225 	 * useful to allow hosts to advertise some parameters such as prefix
226 	 * information and link MTU. Thus, we allow hosts to invoke rtadvd
227 	 * only when router lifetime (on every advertising interface) is
228 	 * explicitly set zero. (see also the above section)
229 	 */
230 	if (val && forwarding == 0) {
231 		syslog(LOG_ERR,
232 		       "<%s> non zero router lifetime is specified for %s, "
233 		       "which must not be allowed for hosts.  you must "
234 		       "change router lifetime or enable IPv6 forwarding.",
235 		       __func__, intface);
236 		exit(1);
237 	}
238 	tmp->lifetime = val & 0xffff;
239 
240 	MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME);
241 	if (val < 0 || val > MAXREACHABLETIME) {
242 		syslog(LOG_ERR,
243 		       "<%s> reachable time (%ld) on %s is invalid "
244 		       "(must be no greater than %d)",
245 		       __func__, val, intface, MAXREACHABLETIME);
246 		exit(1);
247 	}
248 	tmp->reachabletime = (u_int32_t)val;
249 
250 	MAYHAVE(val64, "retrans", DEF_ADVRETRANSTIMER);
251 	if (val64 < 0 || val64 > 0xffffffff) {
252 		syslog(LOG_ERR, "<%s> retrans time (%lld) on %s out of range",
253 		       __func__, (long long)val64, intface);
254 		exit(1);
255 	}
256 	tmp->retranstimer = (u_int32_t)val64;
257 
258 	if (agetnum("hapref") != -1 || agetnum("hatime") != -1) {
259 		syslog(LOG_ERR,
260 		       "<%s> mobile-ip6 configuration not supported",
261 		       __func__);
262 		exit(1);
263 	}
264 	/* prefix information */
265 
266 	/*
267 	 * This is an implementation specific parameter to consider
268 	 * link propagation delays and poorly synchronized clocks when
269 	 * checking consistency of advertised lifetimes.
270 	 */
271 	MAYHAVE(val, "clockskew", 0);
272 	tmp->clockskew = val;
273 
274 	tmp->pfxs = 0;
275 	for (i = -1; i < MAXPREFIX; i++) {
276 		struct prefix *pfx;
277 		char entbuf[256];
278 
279 		makeentry(entbuf, sizeof(entbuf), i, "addr");
280 		addr = (char *)agetstr(entbuf, &bp);
281 		if (addr == NULL)
282 			continue;
283 
284 		/* allocate memory to store prefix information */
285 		if ((pfx = malloc(sizeof(struct prefix))) == NULL) {
286 			syslog(LOG_ERR,
287 			       "<%s> can't allocate enough memory",
288 			       __func__);
289 			exit(1);
290 		}
291 		memset(pfx, 0, sizeof(*pfx));
292 
293 		/* link into chain */
294 		insque(pfx, &tmp->prefix);
295 		tmp->pfxs++;
296 		pfx->rainfo = tmp;
297 
298 		pfx->origin = PREFIX_FROM_CONFIG;
299 
300 		if (inet_pton(AF_INET6, addr, &pfx->prefix) != 1) {
301 			syslog(LOG_ERR,
302 			       "<%s> inet_pton failed for %s",
303 			       __func__, addr);
304 			exit(1);
305 		}
306 		if (IN6_IS_ADDR_MULTICAST(&pfx->prefix)) {
307 			syslog(LOG_ERR,
308 			       "<%s> multicast prefix (%s) must "
309 			       "not be advertised on %s",
310 			       __func__, addr, intface);
311 			exit(1);
312 		}
313 		if (IN6_IS_ADDR_LINKLOCAL(&pfx->prefix))
314 			syslog(LOG_NOTICE,
315 			       "<%s> link-local prefix (%s) will be"
316 			       " advertised on %s",
317 			       __func__, addr, intface);
318 
319 		makeentry(entbuf, sizeof(entbuf), i, "prefixlen");
320 		MAYHAVE(val, entbuf, 64);
321 		if (val < 0 || val > 128) {
322 			syslog(LOG_ERR, "<%s> prefixlen (%ld) for %s "
323 			       "on %s out of range",
324 			       __func__, val, addr, intface);
325 			exit(1);
326 		}
327 		pfx->prefixlen = (int)val;
328 
329 		makeentry(entbuf, sizeof(entbuf), i, "pinfoflags");
330 		if ((flagstr = (char *)agetstr(entbuf, &bp))) {
331 			val = 0;
332 			if (strchr(flagstr, 'l'))
333 				val |= ND_OPT_PI_FLAG_ONLINK;
334 			if (strchr(flagstr, 'a'))
335 				val |= ND_OPT_PI_FLAG_AUTO;
336 		} else {
337 			MAYHAVE(val, entbuf,
338 			    (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO));
339 		}
340 		pfx->onlinkflg = val & ND_OPT_PI_FLAG_ONLINK;
341 		pfx->autoconfflg = val & ND_OPT_PI_FLAG_AUTO;
342 
343 		makeentry(entbuf, sizeof(entbuf), i, "vltime");
344 		MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
345 		if (val64 < 0 || val64 > 0xffffffff) {
346 			syslog(LOG_ERR, "<%s> vltime (%lld) for "
347 			    "%s/%d on %s is out of range",
348 			    __func__, (long long)val64,
349 			    addr, pfx->prefixlen, intface);
350 			exit(1);
351 		}
352 		pfx->validlifetime = (u_int32_t)val64;
353 
354 		makeentry(entbuf, sizeof(entbuf), i, "vltimedecr");
355 		if (agetflag(entbuf)) {
356 			struct timeval now;
357 			gettimeofday(&now, 0);
358 			pfx->vltimeexpire =
359 				now.tv_sec + pfx->validlifetime;
360 		}
361 
362 		makeentry(entbuf, sizeof(entbuf), i, "pltime");
363 		MAYHAVE(val64, entbuf, DEF_ADVPREFERREDLIFETIME);
364 		if (val64 < 0 || val64 > 0xffffffff) {
365 			syslog(LOG_ERR,
366 			    "<%s> pltime (%lld) for %s/%d on %s "
367 			    "is out of range",
368 			    __func__, (long long)val64,
369 			    addr, pfx->prefixlen, intface);
370 			exit(1);
371 		}
372 		pfx->preflifetime = (u_int32_t)val64;
373 
374 		makeentry(entbuf, sizeof(entbuf), i, "pltimedecr");
375 		if (agetflag(entbuf)) {
376 			struct timeval now;
377 			gettimeofday(&now, 0);
378 			pfx->pltimeexpire =
379 				now.tv_sec + pfx->preflifetime;
380 		}
381 	}
382 	if (tmp->pfxs == 0)
383 		get_prefix(tmp);
384 
385 	MAYHAVE(val, "mtu", 0);
386 	if (val < 0 || val > 0xffffffff) {
387 		syslog(LOG_ERR,
388 		       "<%s> mtu (%ld) on %s out of range",
389 		       __func__, val, intface);
390 		exit(1);
391 	}
392 	tmp->linkmtu = (u_int32_t)val;
393 	if (tmp->linkmtu == 0) {
394 		char *mtustr;
395 
396 		if ((mtustr = (char *)agetstr("mtu", &bp)) &&
397 		    strcmp(mtustr, "auto") == 0)
398 			tmp->linkmtu = tmp->phymtu;
399 	}
400 	else if (tmp->linkmtu < IPV6_MMTU || tmp->linkmtu > tmp->phymtu) {
401 		syslog(LOG_ERR,
402 		       "<%s> advertised link mtu (%lu) on %s is invalid (must "
403 		       "be between least MTU (%d) and physical link MTU (%d)",
404 		       __func__, (unsigned long)tmp->linkmtu, intface,
405 		       IPV6_MMTU, tmp->phymtu);
406 		exit(1);
407 	}
408 
409 	/* route information */
410 #ifdef ROUTEINFO
411 	tmp->routes = 0;
412 	for (i = -1; i < MAXROUTE; i++) {
413 		struct rtinfo *rti;
414 		char entbuf[256], oentbuf[256];
415 
416 		makeentry(entbuf, sizeof(entbuf), i, "rtprefix");
417 		addr = (char *)agetstr(entbuf, &bp);
418 		if (addr == NULL) {
419 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrprefix");
420 			addr = (char *)agetstr(oentbuf, &bp);
421 			if (addr) {
422 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
423 					oentbuf, entbuf);
424 			}
425 		}
426 		if (addr == NULL)
427 			continue;
428 
429 		/* allocate memory to store prefix information */
430 		if ((rti = malloc(sizeof(struct rtinfo))) == NULL) {
431 			syslog(LOG_ERR,
432 			       "<%s> can't allocate enough memory",
433 			       __func__);
434 			exit(1);
435 		}
436 		memset(rti, 0, sizeof(*rti));
437 
438 		/* link into chain */
439 		insque(rti, &tmp->route);
440 		tmp->routes++;
441 
442 		if (inet_pton(AF_INET6, addr, &rti->prefix) != 1) {
443 			syslog(LOG_ERR, "<%s> inet_pton failed for %s",
444 			       __func__, addr);
445 			exit(1);
446 		}
447 #if 0
448 		/*
449 		 * XXX: currently there's no restriction in route information
450 		 * prefix according to
451 		 * draft-ietf-ipngwg-router-selection-00.txt.
452 		 * However, I think the similar restriction be necessary.
453 		 */
454 		MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
455 		if (IN6_IS_ADDR_MULTICAST(&rti->prefix)) {
456 			syslog(LOG_ERR,
457 			       "<%s> multicast route (%s) must "
458 			       "not be advertised on %s",
459 			       __func__, addr, intface);
460 			exit(1);
461 		}
462 		if (IN6_IS_ADDR_LINKLOCAL(&rti->prefix)) {
463 			syslog(LOG_NOTICE,
464 			       "<%s> link-local route (%s) will "
465 			       "be advertised on %s",
466 			       __func__, addr, intface);
467 			exit(1);
468 		}
469 #endif
470 
471 		makeentry(entbuf, sizeof(entbuf), i, "rtplen");
472 		/* XXX: 256 is a magic number for compatibility check. */
473 		MAYHAVE(val, entbuf, 256);
474 		if (val == 256) {
475 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrplen");
476 			MAYHAVE(val, oentbuf, 256);
477 			if (val != 256) {
478 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
479 					oentbuf, entbuf);
480 			} else
481 				val = 64;
482 		}
483 		if (val < 0 || val > 128) {
484 			syslog(LOG_ERR, "<%s> prefixlen (%ld) for %s on %s "
485 			       "out of range",
486 			       __func__, val, addr, intface);
487 			exit(1);
488 		}
489 		rti->prefixlen = (int)val;
490 
491 		makeentry(entbuf, sizeof(entbuf), i, "rtflags");
492 		if ((flagstr = (char *)agetstr(entbuf, &bp))) {
493 			val = 0;
494 			if (strchr(flagstr, 'h'))
495 				val |= ND_RA_FLAG_RTPREF_HIGH;
496 			if (strchr(flagstr, 'l')) {
497 				if ((val & ND_RA_FLAG_RTPREF_HIGH)) {
498 					syslog(LOG_ERR,
499 					    "<%s> the \'h\' and \'l\' route"
500 					    " preferences are exclusive",
501 					    __func__);
502 					exit(1);
503 				}
504 				val |= ND_RA_FLAG_RTPREF_LOW;
505 			}
506 		} else
507 			MAYHAVE(val, entbuf, 256); /* XXX */
508 		if (val == 256) {
509 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrflags");
510 			MAYHAVE(val, oentbuf, 256);
511 			if (val != 256) {
512 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
513 					oentbuf, entbuf);
514 			} else
515 				val = 0;
516 		}
517 		rti->rtpref = val & ND_RA_FLAG_RTPREF_MASK;
518 		if (rti->rtpref == ND_RA_FLAG_RTPREF_RSV) {
519 			syslog(LOG_ERR, "<%s> invalid route preference (%02x) "
520 			       "for %s/%d on %s",
521 			       __func__, rti->rtpref, addr,
522 			       rti->prefixlen, intface);
523 			exit(1);
524 		}
525 
526 		/*
527 		 * Since the spec does not a default value, we should make
528 		 * this entry mandatory.  However, FreeBSD 4.4 has shipped
529 		 * with this field being optional, we use the router lifetime
530 		 * as an ad-hoc default value with a warning message.
531 		 */
532 		makeentry(entbuf, sizeof(entbuf), i, "rtltime");
533 		MAYHAVE(val64, entbuf, -1);
534 		if (val64 == -1) {
535 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrltime");
536 			MAYHAVE(val64, oentbuf, -1);
537 			if (val64 != -1) {
538 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
539 					oentbuf, entbuf);
540 			} else {
541 				fprintf(stderr, "%s should be specified "
542 					"for interface %s.\n",
543 					entbuf, intface);
544 				val64 = tmp->lifetime;
545 			}
546 		}
547 		if (val64 < 0 || val64 > 0xffffffff) {
548 			syslog(LOG_ERR, "<%s> route lifetime (%lld) for "
549 			    "%s/%d on %s out of range", __func__,
550 			    (long long)val64, addr, rti->prefixlen, intface);
551 			exit(1);
552 		}
553 		rti->ltime = (u_int32_t)val64;
554 	}
555 #endif
556 
557 	/* okey */
558 	tmp->next = ralist;
559 	ralist = tmp;
560 
561 	/* construct the sending packet */
562 	make_packet(tmp);
563 
564 	/* set timer */
565 	tmp->timer = rtadvd_add_timer(ra_timeout, ra_timer_update,
566 				      tmp, tmp);
567 	ra_timer_update((void *)tmp, &tmp->timer->tm);
568 	rtadvd_set_timer(&tmp->timer->tm, tmp->timer);
569 }
570 
571 void
572 get_prefix(struct rainfo *rai)
573 {
574 	struct ifaddrs *ifap, *ifa;
575 	struct prefix *pp;
576 	struct in6_addr *a;
577 	u_char *p, *ep, *m, *lim;
578 	u_char ntopbuf[INET6_ADDRSTRLEN];
579 
580 	if (getifaddrs(&ifap) < 0) {
581 		syslog(LOG_ERR,
582 		       "<%s> can't get interface addresses",
583 		       __func__);
584 		exit(1);
585 	}
586 
587 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
588 		int plen;
589 
590 		if (strcmp(ifa->ifa_name, rai->ifname) != 0)
591 			continue;
592 		if (ifa->ifa_addr->sa_family != AF_INET6)
593 			continue;
594 		a = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
595 		if (IN6_IS_ADDR_LINKLOCAL(a))
596 			continue;
597 		/* get prefix length */
598 		m = (u_char *)&((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr;
599 		lim = (u_char *)(ifa->ifa_netmask) + ifa->ifa_netmask->sa_len;
600 		plen = prefixlen(m, lim);
601 		if (plen <= 0 || plen > 128) {
602 			syslog(LOG_ERR, "<%s> failed to get prefixlen "
603 			       "or prefix is invalid",
604 			       __func__);
605 			exit(1);
606 		}
607 		if (plen == 128)	/* XXX */
608 			continue;
609 		if (find_prefix(rai, a, plen)) {
610 			/* ignore a duplicated prefix. */
611 			continue;
612 		}
613 
614 		/* allocate memory to store prefix info. */
615 		if ((pp = malloc(sizeof(*pp))) == NULL) {
616 			syslog(LOG_ERR,
617 			       "<%s> can't get allocate buffer for prefix",
618 			       __func__);
619 			exit(1);
620 		}
621 		memset(pp, 0, sizeof(*pp));
622 
623 		/* set prefix, sweep bits outside of prefixlen */
624 		pp->prefixlen = plen;
625 		memcpy(&pp->prefix, a, sizeof(*a));
626 		p = (u_char *)&pp->prefix;
627 		ep = (u_char *)(&pp->prefix + 1);
628 		while (m < lim)
629 			*p++ &= *m++;
630 		while (p < ep)
631 			*p++ = 0x00;
632 	        if (!inet_ntop(AF_INET6, &pp->prefix, ntopbuf,
633 	            sizeof(ntopbuf))) {
634 			syslog(LOG_ERR, "<%s> inet_ntop failed", __func__);
635 			exit(1);
636 		}
637 		syslog(LOG_DEBUG,
638 		       "<%s> add %s/%d to prefix list on %s",
639 		       __func__, ntopbuf, pp->prefixlen, rai->ifname);
640 
641 		/* set other fields with protocol defaults */
642 		pp->validlifetime = DEF_ADVVALIDLIFETIME;
643 		pp->preflifetime = DEF_ADVPREFERREDLIFETIME;
644 		pp->onlinkflg = 1;
645 		pp->autoconfflg = 1;
646 		pp->origin = PREFIX_FROM_KERNEL;
647 		pp->rainfo = rai;
648 
649 		/* link into chain */
650 		insque(pp, &rai->prefix);
651 
652 		/* counter increment */
653 		rai->pfxs++;
654 	}
655 
656 	freeifaddrs(ifap);
657 }
658 
659 static void
660 makeentry(buf, len, id, string)
661 	char *buf;
662 	size_t len;
663 	int id;
664 	char *string;
665 {
666 
667 	if (id < 0)
668 		strlcpy(buf, string, len);
669 	else
670 		snprintf(buf, len, "%s%d", string, id);
671 }
672 
673 /*
674  * Add a prefix to the list of specified interface and reconstruct
675  * the outgoing packet.
676  * The prefix must not be in the list.
677  * XXX: other parameters of the prefix (e.g. lifetime) shoule be
678  * able to be specified.
679  */
680 static void
681 add_prefix(struct rainfo *rai, struct in6_prefixreq *ipr)
682 {
683 	struct prefix *prefix;
684 	u_char ntopbuf[INET6_ADDRSTRLEN];
685 
686 	if ((prefix = malloc(sizeof(*prefix))) == NULL) {
687 		syslog(LOG_ERR, "<%s> memory allocation failed",
688 		       __func__);
689 		return;		/* XXX: error or exit? */
690 	}
691 	memset(prefix, 0, sizeof(*prefix));
692 	prefix->prefix = ipr->ipr_prefix.sin6_addr;
693 	prefix->prefixlen = ipr->ipr_plen;
694 	prefix->validlifetime = ipr->ipr_vltime;
695 	prefix->preflifetime = ipr->ipr_pltime;
696 	prefix->onlinkflg = ipr->ipr_raf_onlink;
697 	prefix->autoconfflg = ipr->ipr_raf_auto;
698 	prefix->origin = PREFIX_FROM_DYNAMIC;
699 
700 	insque(prefix, &rai->prefix);
701 	prefix->rainfo = rai;
702 
703 	syslog(LOG_DEBUG, "<%s> new prefix %s/%d was added on %s",
704 	       __func__, inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr,
705 				       ntopbuf, INET6_ADDRSTRLEN),
706 	       ipr->ipr_plen, rai->ifname);
707 
708 	/* free the previous packet */
709 	free(rai->ra_data);
710 	rai->ra_data = NULL;
711 
712 	/* reconstruct the packet */
713 	rai->pfxs++;
714 	make_packet(rai);
715 }
716 
717 /*
718  * Delete a prefix to the list of specified interface and reconstruct
719  * the outgoing packet.
720  * The prefix must be in the list.
721  */
722 void
723 delete_prefix(struct prefix *prefix)
724 {
725 	u_char ntopbuf[INET6_ADDRSTRLEN];
726 	struct rainfo *rai = prefix->rainfo;
727 
728 	remque(prefix);
729 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was deleted on %s",
730 	       __func__, inet_ntop(AF_INET6, &prefix->prefix,
731 				       ntopbuf, INET6_ADDRSTRLEN),
732 	       prefix->prefixlen, rai->ifname);
733 	if (prefix->timer)
734 		rtadvd_remove_timer(&prefix->timer);
735 	free(prefix);
736 	rai->pfxs--;
737 }
738 
739 void
740 invalidate_prefix(struct prefix *prefix)
741 {
742 	u_char ntopbuf[INET6_ADDRSTRLEN];
743 	struct timeval timo;
744 	struct rainfo *rai = prefix->rainfo;
745 
746 	if (prefix->timer) {	/* sanity check */
747 		syslog(LOG_ERR,
748 		    "<%s> assumption failure: timer already exists",
749 		    __func__);
750 		exit(1);
751 	}
752 
753 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was invalidated on %s, "
754 	    "will expire in %ld seconds", __func__,
755 	    inet_ntop(AF_INET6, &prefix->prefix, ntopbuf, INET6_ADDRSTRLEN),
756 	    prefix->prefixlen, rai->ifname, (long)prefix_timo);
757 
758 	/* set the expiration timer */
759 	prefix->timer = rtadvd_add_timer(prefix_timeout, NULL, prefix, NULL);
760 	if (prefix->timer == NULL) {
761 		syslog(LOG_ERR, "<%s> failed to add a timer for a prefix. "
762 		    "remove the prefix", __func__);
763 		delete_prefix(prefix);
764 	}
765 	timo.tv_sec = prefix_timo;
766 	timo.tv_usec = 0;
767 	rtadvd_set_timer(&timo, prefix->timer);
768 }
769 
770 static struct rtadvd_timer *
771 prefix_timeout(void *arg)
772 {
773 	struct prefix *prefix = (struct prefix *)arg;
774 
775 	delete_prefix(prefix);
776 
777 	return(NULL);
778 }
779 
780 void
781 update_prefix(struct prefix * prefix)
782 {
783 	u_char ntopbuf[INET6_ADDRSTRLEN];
784 	struct rainfo *rai = prefix->rainfo;
785 
786 	if (prefix->timer == NULL) { /* sanity check */
787 		syslog(LOG_ERR,
788 		    "<%s> assumption failure: timer does not exist",
789 		    __func__);
790 		exit(1);
791 	}
792 
793 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was re-enabled on %s",
794 	    __func__, inet_ntop(AF_INET6, &prefix->prefix, ntopbuf,
795 	    INET6_ADDRSTRLEN), prefix->prefixlen, rai->ifname);
796 
797 	/* stop the expiration timer */
798 	rtadvd_remove_timer(&prefix->timer);
799 }
800 
801 /*
802  * Try to get an in6_prefixreq contents for a prefix which matches
803  * ipr->ipr_prefix and ipr->ipr_plen and belongs to
804  * the interface whose name is ipr->ipr_name[].
805  */
806 static int
807 init_prefix(struct in6_prefixreq *ipr)
808 {
809 #if 0
810 	int s;
811 
812 	if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
813 		syslog(LOG_ERR, "<%s> socket: %s", __func__,
814 		       strerror(errno));
815 		exit(1);
816 	}
817 
818 	if (ioctl(s, SIOCGIFPREFIX_IN6, (caddr_t)ipr) < 0) {
819 		syslog(LOG_INFO, "<%s> ioctl:SIOCGIFPREFIX %s", __func__,
820 		       strerror(errno));
821 
822 		ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
823 		ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
824 		ipr->ipr_raf_onlink = 1;
825 		ipr->ipr_raf_auto = 1;
826 		/* omit other field initialization */
827 	}
828 	else if (ipr->ipr_origin < PR_ORIG_RR) {
829 		u_char ntopbuf[INET6_ADDRSTRLEN];
830 
831 		syslog(LOG_WARNING, "<%s> Added prefix(%s)'s origin %d is"
832 		       "lower than PR_ORIG_RR(router renumbering)."
833 		       "This should not happen if I am router", __func__,
834 		       inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf,
835 				 sizeof(ntopbuf)), ipr->ipr_origin);
836 		close(s);
837 		return 1;
838 	}
839 
840 	close(s);
841 	return 0;
842 #else
843 	ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
844 	ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
845 	ipr->ipr_raf_onlink = 1;
846 	ipr->ipr_raf_auto = 1;
847 	return 0;
848 #endif
849 }
850 
851 void
852 make_prefix(struct rainfo *rai, int ifindex, struct in6_addr *addr, int plen)
853 {
854 	struct in6_prefixreq ipr;
855 
856 	memset(&ipr, 0, sizeof(ipr));
857 	if (if_indextoname(ifindex, ipr.ipr_name) == NULL) {
858 		syslog(LOG_ERR, "<%s> Prefix added interface No.%d doesn't"
859 		       "exist. This should not happen! %s", __func__,
860 		       ifindex, strerror(errno));
861 		exit(1);
862 	}
863 	ipr.ipr_prefix.sin6_len = sizeof(ipr.ipr_prefix);
864 	ipr.ipr_prefix.sin6_family = AF_INET6;
865 	ipr.ipr_prefix.sin6_addr = *addr;
866 	ipr.ipr_plen = plen;
867 
868 	if (init_prefix(&ipr))
869 		return; /* init failed by some error */
870 	add_prefix(rai, &ipr);
871 }
872 
873 void
874 make_packet(struct rainfo *rainfo)
875 {
876 	size_t packlen, lladdroptlen = 0;
877 	char *buf;
878 	struct nd_router_advert *ra;
879 	struct nd_opt_prefix_info *ndopt_pi;
880 	struct nd_opt_mtu *ndopt_mtu;
881 #ifdef ROUTEINFO
882 	struct nd_opt_route_info *ndopt_rti;
883 	struct rtinfo *rti;
884 #endif
885 	struct prefix *pfx;
886 
887 	/* calculate total length */
888 	packlen = sizeof(struct nd_router_advert);
889 	if (rainfo->advlinkopt) {
890 		if ((lladdroptlen = lladdropt_length(rainfo->sdl)) == 0) {
891 			syslog(LOG_INFO,
892 			       "<%s> link-layer address option has"
893 			       " null length on %s.  Treat as not included.",
894 			       __func__, rainfo->ifname);
895 			rainfo->advlinkopt = 0;
896 		}
897 		packlen += lladdroptlen;
898 	}
899 	if (rainfo->pfxs)
900 		packlen += sizeof(struct nd_opt_prefix_info) * rainfo->pfxs;
901 	if (rainfo->linkmtu)
902 		packlen += sizeof(struct nd_opt_mtu);
903 #ifdef ROUTEINFO
904 	for (rti = rainfo->route.next; rti != &rainfo->route; rti = rti->next)
905 		packlen += sizeof(struct nd_opt_route_info) +
906 			   ((rti->prefixlen + 0x3f) >> 6) * 8;
907 #endif
908 
909 	/* allocate memory for the packet */
910 	if ((buf = malloc(packlen)) == NULL) {
911 		syslog(LOG_ERR,
912 		       "<%s> can't get enough memory for an RA packet",
913 		       __func__);
914 		exit(1);
915 	}
916 	if (rainfo->ra_data) {
917 		/* free the previous packet */
918 		free(rainfo->ra_data);
919 		rainfo->ra_data = NULL;
920 	}
921 	rainfo->ra_data = buf;
922 	/* XXX: what if packlen > 576? */
923 	rainfo->ra_datalen = packlen;
924 
925 	/*
926 	 * construct the packet
927 	 */
928 	ra = (struct nd_router_advert *)buf;
929 	ra->nd_ra_type = ND_ROUTER_ADVERT;
930 	ra->nd_ra_code = 0;
931 	ra->nd_ra_cksum = 0;
932 	ra->nd_ra_curhoplimit = (u_int8_t)(0xff & rainfo->hoplimit);
933 	ra->nd_ra_flags_reserved = 0; /* just in case */
934 	/*
935 	 * XXX: the router preference field, which is a 2-bit field, should be
936 	 * initialized before other fields.
937 	 */
938 	ra->nd_ra_flags_reserved = 0xff & rainfo->rtpref;
939 	ra->nd_ra_flags_reserved |=
940 		rainfo->managedflg ? ND_RA_FLAG_MANAGED : 0;
941 	ra->nd_ra_flags_reserved |=
942 		rainfo->otherflg ? ND_RA_FLAG_OTHER : 0;
943 	ra->nd_ra_router_lifetime = htons(rainfo->lifetime);
944 	ra->nd_ra_reachable = htonl(rainfo->reachabletime);
945 	ra->nd_ra_retransmit = htonl(rainfo->retranstimer);
946 	buf += sizeof(*ra);
947 
948 	if (rainfo->advlinkopt) {
949 		lladdropt_fill(rainfo->sdl, (struct nd_opt_hdr *)buf);
950 		buf += lladdroptlen;
951 	}
952 
953 	if (rainfo->linkmtu) {
954 		ndopt_mtu = (struct nd_opt_mtu *)buf;
955 		ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU;
956 		ndopt_mtu->nd_opt_mtu_len = 1;
957 		ndopt_mtu->nd_opt_mtu_reserved = 0;
958 		ndopt_mtu->nd_opt_mtu_mtu = htonl(rainfo->linkmtu);
959 		buf += sizeof(struct nd_opt_mtu);
960 	}
961 
962 	for (pfx = rainfo->prefix.next;
963 	     pfx != &rainfo->prefix; pfx = pfx->next) {
964 		u_int32_t vltime, pltime;
965 		struct timeval now;
966 
967 		ndopt_pi = (struct nd_opt_prefix_info *)buf;
968 		ndopt_pi->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
969 		ndopt_pi->nd_opt_pi_len = 4;
970 		ndopt_pi->nd_opt_pi_prefix_len = pfx->prefixlen;
971 		ndopt_pi->nd_opt_pi_flags_reserved = 0;
972 		if (pfx->onlinkflg)
973 			ndopt_pi->nd_opt_pi_flags_reserved |=
974 				ND_OPT_PI_FLAG_ONLINK;
975 		if (pfx->autoconfflg)
976 			ndopt_pi->nd_opt_pi_flags_reserved |=
977 				ND_OPT_PI_FLAG_AUTO;
978 		if (pfx->timer)
979 			vltime = 0;
980 		else {
981 			if (pfx->vltimeexpire || pfx->pltimeexpire)
982 				gettimeofday(&now, NULL);
983 			if (pfx->vltimeexpire == 0)
984 				vltime = pfx->validlifetime;
985 			else
986 				vltime = (pfx->vltimeexpire > now.tv_sec) ?
987 				    pfx->vltimeexpire - now.tv_sec : 0;
988 		}
989 		if (pfx->timer)
990 			pltime = 0;
991 		else {
992 			if (pfx->pltimeexpire == 0)
993 				pltime = pfx->preflifetime;
994 			else
995 				pltime = (pfx->pltimeexpire > now.tv_sec) ?
996 				    pfx->pltimeexpire - now.tv_sec : 0;
997 		}
998 		if (vltime < pltime) {
999 			/*
1000 			 * this can happen if vltime is decrement but pltime
1001 			 * is not.
1002 			 */
1003 			pltime = vltime;
1004 		}
1005 		ndopt_pi->nd_opt_pi_valid_time = htonl(vltime);
1006 		ndopt_pi->nd_opt_pi_preferred_time = htonl(pltime);
1007 		ndopt_pi->nd_opt_pi_reserved2 = 0;
1008 		ndopt_pi->nd_opt_pi_prefix = pfx->prefix;
1009 
1010 		buf += sizeof(struct nd_opt_prefix_info);
1011 	}
1012 
1013 #ifdef ROUTEINFO
1014 	for (rti = rainfo->route.next; rti != &rainfo->route; rti = rti->next) {
1015 		u_int8_t psize = (rti->prefixlen + 0x3f) >> 6;
1016 
1017 		ndopt_rti = (struct nd_opt_route_info *)buf;
1018 		ndopt_rti->nd_opt_rti_type = ND_OPT_ROUTE_INFO;
1019 		ndopt_rti->nd_opt_rti_len = 1 + psize;
1020 		ndopt_rti->nd_opt_rti_prefixlen = rti->prefixlen;
1021 		ndopt_rti->nd_opt_rti_flags = 0xff & rti->rtpref;
1022 		ndopt_rti->nd_opt_rti_lifetime = htonl(rti->ltime);
1023 		memcpy(ndopt_rti + 1, &rti->prefix, psize * 8);
1024 		buf += sizeof(struct nd_opt_route_info) + psize * 8;
1025 	}
1026 #endif
1027 
1028 	return;
1029 }
1030 
1031 static int
1032 getinet6sysctl(int code)
1033 {
1034 	int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, 0 };
1035 	int value;
1036 	size_t size;
1037 
1038 	mib[3] = code;
1039 	size = sizeof(value);
1040 	if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), &value, &size, NULL, 0)
1041 	    < 0) {
1042 		syslog(LOG_ERR, "<%s>: failed to get ip6 sysctl(%d): %s",
1043 		       __func__, code,
1044 		       strerror(errno));
1045 		return(-1);
1046 	}
1047 	else
1048 		return(value);
1049 }
1050