xref: /minix/usr.sbin/rtadvd/config.c (revision 8f957290)
1 /*	$NetBSD: config.c,v 1.34 2015/06/05 14:09:20 roy Exp $	*/
2 /*	$KAME: config.c,v 1.93 2005/10/17 14:40:02 suz 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/route.h>
41 #include <net/if_dl.h>
42 #ifdef __FreeBSD__
43 #include <net/if_var.h>
44 #endif
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 #include <netinet6/nd6.h>
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 #include <search.h>
61 #include <unistd.h>
62 #include <ifaddrs.h>
63 #include <inttypes.h>
64 
65 #include "rtadvd.h"
66 #include "advcap.h"
67 #include "timer.h"
68 #include "if.h"
69 #include "config.h"
70 
71 #ifndef __arraycount
72 #define __arraycount(__x)	(sizeof(__x) / sizeof(__x[0]))
73 #endif
74 
75 static time_t prefix_timo = (60 * 120);	/* 2 hours.
76 					 * XXX: should be configurable. */
77 static struct rtadvd_timer *prefix_timeout(void *);
78 static void makeentry(char *, size_t, int, const char *);
79 static int getinet6sysctl(int);
80 
81 static size_t
encode_domain(char * dst,const char * src)82 encode_domain(char *dst, const char *src)
83 {
84 	ssize_t len;
85 	char *odst, *p;
86 
87 	odst = dst;
88 	while (src && (len = strlen(src)) != 0) {
89 		p = strchr(src, '.');
90 		*dst++ = len = MIN(63, p == NULL ? len : p - src);
91 		memcpy(dst, src, len);
92 		dst += len;
93 		if (p == NULL)
94 			break;
95 		src = p + 1;
96 	}
97 	*dst++ = '\0';
98 
99 	return dst - odst;
100 }
101 
102 void
free_rainfo(struct rainfo * rai)103 free_rainfo(struct rainfo *rai)
104 {
105 	struct prefix *pfx;
106 	struct rtinfo *rti;
107 	struct rdnss *rdnss;
108 	struct rdnss_addr *rdnsa;
109 	struct dnssl *dnssl;
110 	struct dnssl_domain *dnsd;
111 
112 	rtadvd_remove_timer(&rai->timer);
113 
114 	while ((pfx = TAILQ_FIRST(&rai->prefix))) {
115 		TAILQ_REMOVE(&rai->prefix, pfx, next);
116 		free(pfx);
117 	}
118 
119 	while ((rti = TAILQ_FIRST(&rai->route))) {
120 		TAILQ_REMOVE(&rai->route, rti, next);
121 		free(rti);
122 	}
123 
124 	while ((rdnss = TAILQ_FIRST(&rai->rdnss))) {
125 		TAILQ_REMOVE(&rai->rdnss, rdnss, next);
126 		while ((rdnsa = TAILQ_FIRST(&rdnss->list))) {
127 			TAILQ_REMOVE(&rdnss->list, rdnsa, next);
128 			free(rdnsa);
129 		}
130 		free(rdnss);
131 	}
132 
133 	while ((dnssl = TAILQ_FIRST(&rai->dnssl))) {
134 		TAILQ_REMOVE(&rai->dnssl, dnssl, next);
135 		while ((dnsd = TAILQ_FIRST(&dnssl->list))) {
136 			TAILQ_REMOVE(&dnssl->list, dnsd, next);
137 			free(dnsd);
138 		}
139 		free(dnssl);
140 	}
141 
142 	free(rai->sdl);
143 	free(rai->ra_data);
144 	free(rai);
145 }
146 
147 void
getconfig(const char * intface,int exithard)148 getconfig(const char *intface, int exithard)
149 {
150 	int stat, c, i;
151 	char tbuf[BUFSIZ];
152 	struct rainfo *tmp, *rai;
153 	int32_t val;
154 	int64_t val64;
155 	char buf[BUFSIZ];
156 	char *bp = buf;
157 	char *addr, *flagstr, *ap;
158 	static int forwarding = -1;
159 	char entbuf[256], abuf[256];
160 	struct rdnss *rdnss;
161 	struct dnssl *dnssl;
162 
163 #define MUSTHAVE(var, cap)	\
164     do {								\
165 	int64_t t;							\
166 	if ((t = agetnum(cap)) < 0) {					\
167 		fprintf(stderr, "rtadvd: need %s for interface %s\n",	\
168 			cap, intface);					\
169 		goto errexit;						\
170 	}								\
171 	var = t;							\
172      } while (0)
173 #define MAYHAVE(var, cap, def)	\
174      do {								\
175 	if ((var = agetnum(cap)) < 0)					\
176 		var = def;						\
177      } while (0)
178 #define	ELM_MALLOC(p)					\
179 	do {								\
180 		p = calloc(1, sizeof(*p));				\
181 		if (p == NULL) {					\
182 			syslog(LOG_ERR, "<%s> calloc failed: %m",	\
183 			    __func__);					\
184 			goto errexit;					\
185 		}							\
186 	} while(/*CONSTCOND*/0)
187 
188 	if (if_nametoindex(intface) == 0) {
189 		syslog(LOG_INFO, "<%s> interface %s not found, ignoring",
190 		       __func__, intface);
191 		return;
192 	}
193 
194 	syslog(LOG_DEBUG, "<%s> loading configuration for interface %s",
195 	       __func__, intface);
196 
197 	if ((stat = agetent(tbuf, intface)) <= 0) {
198 		memset(tbuf, 0, sizeof(tbuf));
199 		syslog(LOG_INFO,
200 		       "<%s> %s isn't defined in the configuration file"
201 		       " or the configuration file doesn't exist."
202 		       " Treat it as default",
203 		        __func__, intface);
204 	}
205 
206 	ELM_MALLOC(tmp);
207 	TAILQ_INIT(&tmp->prefix);
208 	TAILQ_INIT(&tmp->route);
209 	TAILQ_INIT(&tmp->rdnss);
210 	TAILQ_INIT(&tmp->dnssl);
211 
212 	/* check if we are allowed to forward packets (if not determined) */
213 	if (forwarding < 0) {
214 		if ((forwarding = getinet6sysctl(IPV6CTL_FORWARDING)) < 0)
215 			exit(1);
216 	}
217 
218 	/* get interface information */
219 	if (agetflag("nolladdr"))
220 		tmp->advlinkopt = 0;
221 	else
222 		tmp->advlinkopt = 1;
223 	if (tmp->advlinkopt) {
224 		if ((tmp->sdl = if_nametosdl(intface)) == NULL) {
225 			syslog(LOG_ERR,
226 			       "<%s> can't get information of %s",
227 			       __func__, intface);
228 			goto errexit;
229 		}
230 		tmp->ifindex = tmp->sdl->sdl_index;
231 	} else {
232 		tmp->ifindex = if_nametoindex(intface);
233 		if (tmp->ifindex == 0) {
234 			syslog(LOG_ERR,
235 			       "<%s> can't get information of %s",
236 			       __func__, intface);
237 			goto errexit;
238 		}
239 	}
240 	tmp->ifflags = if_getflags(tmp->ifindex, 0);
241 	strlcpy(tmp->ifname, intface, sizeof(tmp->ifname));
242 	if ((tmp->phymtu = if_getmtu(intface)) == 0) {
243 		tmp->phymtu = IPV6_MMTU;
244 		syslog(LOG_WARNING,
245 		       "<%s> can't get interface mtu of %s. Treat as %d",
246 		       __func__, intface, IPV6_MMTU);
247 	}
248 
249 	/*
250 	 * set router configuration variables.
251 	 */
252 	MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL);
253 	if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) {
254 		syslog(LOG_ERR,
255 		       "<%s> maxinterval (%d) on %s is invalid "
256 		       "(must be between %u and %u)", __func__, val,
257 		       intface, MIN_MAXINTERVAL, MAX_MAXINTERVAL);
258 		goto errexit;
259 	}
260 	tmp->maxinterval = val;
261 	MAYHAVE(val, "mininterval", tmp->maxinterval/3);
262 	if (val < MIN_MININTERVAL || val > (tmp->maxinterval * 3) / 4) {
263 		syslog(LOG_ERR,
264 		       "<%s> mininterval (%d) on %s is invalid "
265 		       "(must be between %u and %d)",
266 		       __func__, val, intface, MIN_MININTERVAL,
267 		       (tmp->maxinterval * 3) / 4);
268 		goto errexit;
269 	}
270 	tmp->mininterval = val;
271 
272 	MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT);
273 	tmp->hoplimit = val & 0xff;
274 
275 	if ((flagstr = (char *)agetstr("raflags", &bp))) {
276 		val = 0;
277 		if (strchr(flagstr, 'm'))
278 			val |= ND_RA_FLAG_MANAGED;
279 		if (strchr(flagstr, 'o'))
280 			val |= ND_RA_FLAG_OTHER;
281 		if (strchr(flagstr, 'h'))
282 			val |= ND_RA_FLAG_RTPREF_HIGH;
283 		if (strchr(flagstr, 'l')) {
284 			if ((val & ND_RA_FLAG_RTPREF_HIGH)) {
285 				syslog(LOG_ERR, "<%s> the \'h\' and \'l\'"
286 				    " router flags are exclusive", __func__);
287 				goto errexit;
288 			}
289 			val |= ND_RA_FLAG_RTPREF_LOW;
290 		}
291 	} else {
292 		MAYHAVE(val, "raflags", 0);
293 	}
294 	tmp->managedflg = val & ND_RA_FLAG_MANAGED;
295 	tmp->otherflg = val & ND_RA_FLAG_OTHER;
296 #ifndef ND_RA_FLAG_RTPREF_MASK
297 #define ND_RA_FLAG_RTPREF_MASK	0x18 /* 00011000 */
298 #define ND_RA_FLAG_RTPREF_RSV	0x10 /* 00010000 */
299 #endif
300 	tmp->rtpref = val & ND_RA_FLAG_RTPREF_MASK;
301 	if (tmp->rtpref == ND_RA_FLAG_RTPREF_RSV) {
302 		syslog(LOG_ERR, "<%s> invalid router preference (%02x) on %s",
303 		       __func__, tmp->rtpref, intface);
304 		goto errexit;
305 	}
306 
307 	MAYHAVE(val, "rltime", tmp->maxinterval * 3);
308 	if (val && (val < tmp->maxinterval || val > MAXROUTERLIFETIME)) {
309 		syslog(LOG_ERR,
310 		       "<%s> router lifetime (%d) on %s is invalid "
311 		       "(must be 0 or between %d and %d)",
312 		       __func__, val, intface,
313 		       tmp->maxinterval, MAXROUTERLIFETIME);
314 		goto errexit;
315 	}
316 	/*
317 	 * Basically, hosts MUST NOT send Router Advertisement messages at any
318 	 * time (RFC 2461, Section 6.2.3). However, it would sometimes be
319 	 * useful to allow hosts to advertise some parameters such as prefix
320 	 * information and link MTU. Thus, we allow hosts to invoke rtadvd
321 	 * only when router lifetime (on every advertising interface) is
322 	 * explicitly set zero. (see also the above section)
323 	 */
324 	if (val && forwarding == 0) {
325 		syslog(LOG_ERR,
326 		       "<%s> non zero router lifetime is specified for %s, "
327 		       "which must not be allowed for hosts.  you must "
328 		       "change router lifetime or enable IPv6 forwarding.",
329 		       __func__, intface);
330 		goto errexit;
331 	}
332 	tmp->lifetime = val & 0xffff;
333 
334 	MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME);
335 	if (val < 0 || val > MAXREACHABLETIME) {
336 		syslog(LOG_ERR,
337 		       "<%s> reachable time (%d) on %s is invalid "
338 		       "(must be no greater than %d)",
339 		       __func__, val, intface, MAXREACHABLETIME);
340 		goto errexit;
341 	}
342 	tmp->reachabletime = (uint32_t)val;
343 
344 	MAYHAVE(val64, "retrans", DEF_ADVRETRANSTIMER);
345 	if (val64 < 0 || val64 > 0xffffffff) {
346 		syslog(LOG_ERR, "<%s> retrans time (%lld) on %s out of range",
347 		       __func__, (long long)val64, intface);
348 		goto errexit;
349 	}
350 	tmp->retranstimer = (uint32_t)val64;
351 
352 	if (agetnum("hapref") != -1 || agetnum("hatime") != -1) {
353 		syslog(LOG_ERR,
354 		       "<%s> mobile-ip6 configuration not supported",
355 		       __func__);
356 		goto errexit;
357 	}
358 	/* prefix information */
359 
360 	/*
361 	 * This is an implementation specific parameter to consider
362 	 * link propagation delays and poorly synchronized clocks when
363 	 * checking consistency of advertised lifetimes.
364 	 */
365 	MAYHAVE(val, "clockskew", 0);
366 	tmp->clockskew = val;
367 
368 	tmp->pfxs = 0;
369 	for (i = -1; i < MAXPREFIX; i++) {
370 		struct prefix *pfx;
371 
372 		makeentry(entbuf, sizeof(entbuf), i, "addr");
373 		addr = (char *)agetstr(entbuf, &bp);
374 		if (addr == NULL)
375 			continue;
376 
377 		/* allocate memory to store prefix information */
378 		if ((pfx = calloc(1, sizeof(*pfx))) == NULL) {
379 			syslog(LOG_ERR,
380 			       "<%s> can't allocate memory: %m",
381 			       __func__);
382 			goto errexit;
383 		}
384 
385 		TAILQ_INSERT_TAIL(&tmp->prefix, pfx, next);
386 		tmp->pfxs++;
387 		pfx->rainfo = tmp;
388 
389 		pfx->origin = PREFIX_FROM_CONFIG;
390 
391 		if (inet_pton(AF_INET6, addr, &pfx->prefix) != 1) {
392 			syslog(LOG_ERR,
393 			       "<%s> inet_pton failed for %s",
394 			       __func__, addr);
395 			goto errexit;
396 		}
397 		if (IN6_IS_ADDR_MULTICAST(&pfx->prefix)) {
398 			syslog(LOG_ERR,
399 			       "<%s> multicast prefix (%s) must "
400 			       "not be advertised on %s",
401 			       __func__, addr, intface);
402 			goto errexit;
403 		}
404 		if (IN6_IS_ADDR_LINKLOCAL(&pfx->prefix))
405 			syslog(LOG_NOTICE,
406 			       "<%s> link-local prefix (%s) will be"
407 			       " advertised on %s",
408 			       __func__, addr, intface);
409 
410 		makeentry(entbuf, sizeof(entbuf), i, "prefixlen");
411 		MAYHAVE(val, entbuf, 64);
412 		if (val < 0 || val > 128) {
413 			syslog(LOG_ERR, "<%s> prefixlen (%d) for %s "
414 			       "on %s out of range",
415 			       __func__, val, addr, intface);
416 			goto errexit;
417 		}
418 		pfx->prefixlen = (int)val;
419 
420 		makeentry(entbuf, sizeof(entbuf), i, "pinfoflags");
421 		if ((flagstr = (char *)agetstr(entbuf, &bp))) {
422 			val = 0;
423 			if (strchr(flagstr, 'l'))
424 				val |= ND_OPT_PI_FLAG_ONLINK;
425 			if (strchr(flagstr, 'a'))
426 				val |= ND_OPT_PI_FLAG_AUTO;
427 		} else {
428 			MAYHAVE(val, entbuf,
429 			    (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO));
430 		}
431 		pfx->onlinkflg = val & ND_OPT_PI_FLAG_ONLINK;
432 		pfx->autoconfflg = val & ND_OPT_PI_FLAG_AUTO;
433 
434 		makeentry(entbuf, sizeof(entbuf), i, "vltime");
435 		MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
436 		if (val64 < 0 || val64 > 0xffffffff) {
437 			syslog(LOG_ERR, "<%s> vltime (%lld) for "
438 			    "%s/%d on %s is out of range",
439 			    __func__, (long long)val64,
440 			    addr, pfx->prefixlen, intface);
441 			goto errexit;
442 		}
443 		pfx->validlifetime = (uint32_t)val64;
444 
445 		makeentry(entbuf, sizeof(entbuf), i, "vltimedecr");
446 		if (agetflag(entbuf)) {
447 			struct timespec now;
448 			clock_gettime(CLOCK_MONOTONIC, &now);
449 			pfx->vltimeexpire =
450 				now.tv_sec + pfx->validlifetime;
451 		}
452 
453 		makeentry(entbuf, sizeof(entbuf), i, "pltime");
454 		MAYHAVE(val64, entbuf, DEF_ADVPREFERREDLIFETIME);
455 		if (val64 < 0 || val64 > 0xffffffff) {
456 			syslog(LOG_ERR,
457 			    "<%s> pltime (%lld) for %s/%d on %s "
458 			    "is out of range",
459 			    __func__, (long long)val64,
460 			    addr, pfx->prefixlen, intface);
461 			goto errexit;
462 		}
463 		pfx->preflifetime = (uint32_t)val64;
464 
465 		makeentry(entbuf, sizeof(entbuf), i, "pltimedecr");
466 		if (agetflag(entbuf)) {
467 			struct timespec now;
468 			clock_gettime(CLOCK_MONOTONIC, &now);
469 			pfx->pltimeexpire =
470 				now.tv_sec + pfx->preflifetime;
471 		}
472 	}
473 	if (TAILQ_FIRST(&tmp->prefix) == NULL && !agetflag("noifprefix"))
474 		get_prefix(tmp);
475 
476 	MAYHAVE(val64, "mtu", 0);
477 	if (val64 < 0 || val64 > 0xffffffff) {
478 		syslog(LOG_ERR,
479 		       "<%s> mtu (%" PRIi64 ") on %s out of range",
480 		       __func__, val64, intface);
481 		goto errexit;
482 	}
483 	tmp->linkmtu = (uint32_t)val64;
484 	if (tmp->linkmtu == 0) {
485 		char *mtustr;
486 
487 		if ((mtustr = (char *)agetstr("mtu", &bp)) &&
488 		    strcmp(mtustr, "auto") == 0)
489 			tmp->linkmtu = tmp->phymtu;
490 	}
491 	else if (tmp->linkmtu < IPV6_MMTU || tmp->linkmtu > tmp->phymtu) {
492 		syslog(LOG_ERR,
493 		       "<%s> advertised link mtu (%d) on %s is invalid (must "
494 		       "be between least MTU (%d) and physical link MTU (%d)",
495 		       __func__, tmp->linkmtu, intface,
496 		       IPV6_MMTU, tmp->phymtu);
497 		goto errexit;
498 	}
499 
500 #ifdef SIOCSIFINFO_IN6
501 	{
502 		struct in6_ndireq ndi;
503 		int s;
504 
505 		if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
506 			syslog(LOG_ERR, "<%s> socket: %m", __func__);
507 			goto errexit;
508 		}
509 		memset(&ndi, 0, sizeof(ndi));
510 		strncpy(ndi.ifname, intface, IFNAMSIZ);
511 		if (ioctl(s, SIOCGIFINFO_IN6, &ndi) < 0) {
512 			syslog(LOG_INFO, "<%s> ioctl:SIOCGIFINFO_IN6 at %s: %m",
513 			     __func__, intface);
514 		}
515 
516 		/* reflect the RA info to the host variables in kernel */
517 		ndi.ndi.chlim = tmp->hoplimit;
518 		ndi.ndi.retrans = tmp->retranstimer;
519 		ndi.ndi.basereachable = tmp->reachabletime;
520 		if (ioctl(s, SIOCSIFINFO_IN6, &ndi) < 0) {
521 			syslog(LOG_INFO, "<%s> ioctl:SIOCSIFINFO_IN6 at %s: %m",
522 			     __func__, intface);
523 		}
524 		close(s);
525 	}
526 #endif
527 
528 	/* route information */
529 	for (i = -1; i < MAXROUTE; i++) {
530 		struct rtinfo *rti;
531 		char oentbuf[256];
532 
533 		makeentry(entbuf, sizeof(entbuf), i, "rtprefix");
534 		addr = (char *)agetstr(entbuf, &bp);
535 		if (addr == NULL) {
536 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrprefix");
537 			addr = (char *)agetstr(oentbuf, &bp);
538 			if (addr) {
539 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
540 					oentbuf, entbuf);
541 			}
542 		}
543 		if (addr == NULL)
544 			continue;
545 
546 		ELM_MALLOC(rti);
547 		memset(rti, 0, sizeof(*rti));
548 
549 		/* link into chain */
550 		TAILQ_INSERT_TAIL(&tmp->route, rti, next);
551 
552 		if (inet_pton(AF_INET6, addr, &rti->prefix) != 1) {
553 			syslog(LOG_ERR, "<%s> inet_pton failed for %s",
554 			       __func__, addr);
555 			goto errexit;
556 		}
557 #if 0
558 		/*
559 		 * XXX: currently there's no restriction in route information
560 		 * prefix according to
561 		 * draft-ietf-ipngwg-router-selection-00.txt.
562 		 * However, I think the similar restriction be necessary.
563 		 */
564 		MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
565 		if (IN6_IS_ADDR_MULTICAST(&rti->prefix)) {
566 			syslog(LOG_ERR,
567 			       "<%s> multicast route (%s) must "
568 			       "not be advertised on %s",
569 			       __func__, addr, intface);
570 			goto errexit;
571 		}
572 		if (IN6_IS_ADDR_LINKLOCAL(&rti->prefix)) {
573 			syslog(LOG_NOTICE,
574 			       "<%s> link-local route (%s) will "
575 			       "be advertised on %s",
576 			       __func__, addr, intface);
577 			goto errexit;
578 		}
579 #endif
580 
581 		makeentry(entbuf, sizeof(entbuf), i, "rtplen");
582 		/* XXX: 256 is a magic number for compatibility check. */
583 		MAYHAVE(val, entbuf, 256);
584 		if (val == 256) {
585 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrplen");
586 			MAYHAVE(val, oentbuf, 256);
587 			if (val != 256) {
588 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
589 					oentbuf, entbuf);
590 			} else
591 				val = 64;
592 		}
593 		if (val < 0 || val > 128) {
594 			syslog(LOG_ERR, "<%s> prefixlen (%d) for %s on %s "
595 			       "out of range",
596 			       __func__, val, addr, intface);
597 			goto errexit;
598 		}
599 		rti->prefixlen = (int)val;
600 
601 		makeentry(entbuf, sizeof(entbuf), i, "rtflags");
602 		if ((flagstr = (char *)agetstr(entbuf, &bp))) {
603 			val = 0;
604 			if (strchr(flagstr, 'h'))
605 				val |= ND_RA_FLAG_RTPREF_HIGH;
606 			if (strchr(flagstr, 'l')) {
607 				if ((val & ND_RA_FLAG_RTPREF_HIGH)) {
608 					syslog(LOG_ERR,
609 					    "<%s> the \'h\' and \'l\' route"
610 					    " preferences are exclusive",
611 					    __func__);
612 					goto errexit;
613 				}
614 				val |= ND_RA_FLAG_RTPREF_LOW;
615 			}
616 		} else
617 			MAYHAVE(val, entbuf, 256); /* XXX */
618 		if (val == 256) {
619 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrflags");
620 			MAYHAVE(val, oentbuf, 256);
621 			if (val != 256) {
622 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
623 					oentbuf, entbuf);
624 			} else
625 				val = 0;
626 		}
627 		rti->rtpref = val & ND_RA_FLAG_RTPREF_MASK;
628 		if (rti->rtpref == ND_RA_FLAG_RTPREF_RSV) {
629 			syslog(LOG_ERR, "<%s> invalid route preference (%02x) "
630 			       "for %s/%d on %s",
631 			       __func__, rti->rtpref, addr,
632 			       rti->prefixlen, intface);
633 			goto errexit;
634 		}
635 
636 		/*
637 		 * Since the spec does not a default value, we should make
638 		 * this entry mandatory.  However, FreeBSD 4.4 has shipped
639 		 * with this field being optional, we use the router lifetime
640 		 * as an ad-hoc default value with a warning message.
641 		 */
642 		makeentry(entbuf, sizeof(entbuf), i, "rtltime");
643 		MAYHAVE(val64, entbuf, -1);
644 		if (val64 == -1) {
645 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrltime");
646 			MAYHAVE(val64, oentbuf, -1);
647 			if (val64 != -1) {
648 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
649 					oentbuf, entbuf);
650 			} else {
651 				fprintf(stderr, "%s should be specified "
652 					"for interface %s.\n",
653 					entbuf, intface);
654 				val64 = tmp->lifetime;
655 			}
656 		}
657 		if (val64 < 0 || val64 > 0xffffffff) {
658 			syslog(LOG_ERR, "<%s> route lifetime (%lld) for "
659 			    "%s/%d on %s out of range", __func__,
660 			    (long long)val64, addr, rti->prefixlen, intface);
661 			goto errexit;
662 		}
663 		rti->ltime = (uint32_t)val64;
664 	}
665 
666 	/* RDNSS */
667 	for (i = -1; i < MAXRDNSS; i++) {
668 		struct rdnss_addr *rdnsa;
669 
670 		makeentry(entbuf, sizeof(entbuf), i, "rdnss");
671 		addr = (char *)agetstr(entbuf, &bp);
672 		if (addr == NULL)
673 			continue;
674 
675 		ELM_MALLOC(rdnss);
676 		TAILQ_INSERT_TAIL(&tmp->rdnss, rdnss, next);
677 		TAILQ_INIT(&rdnss->list);
678 
679 		for (ap = addr; ap - addr < (ssize_t)strlen(addr); ap += c+1) {
680 			c = strcspn(ap, ",");
681 			strncpy(abuf, ap, c);
682 			abuf[c] = '\0';
683 			ELM_MALLOC(rdnsa);
684 			TAILQ_INSERT_TAIL(&rdnss->list, rdnsa, next);
685 			if (inet_pton(AF_INET6, abuf, &rdnsa->addr) != 1) {
686 				syslog(LOG_ERR, "<%s> inet_pton failed for %s",
687 			           __func__, addr);
688 				goto errexit;
689 			}
690 		}
691 
692 		makeentry(entbuf, sizeof(entbuf), i, "rdnssltime");
693 		MAYHAVE(val64, entbuf, tmp->maxinterval * 3 / 2);
694 		if (val64 < tmp->maxinterval ||
695 		    val64 > tmp->maxinterval * 2)
696 		{
697 			syslog(LOG_ERR, "<%s> %s (%lld) on %s is invalid",
698 		    	     __func__, entbuf, (long long)val64, intface);
699 			goto errexit;
700 		}
701 		rdnss->lifetime = (uint32_t)val64;
702 
703 	}
704 
705 	/* DNSSL */
706 	TAILQ_INIT(&tmp->dnssl);
707 	for (i = -1; i < MAXDNSSL; i++) {
708 		struct dnssl_domain *dnsd;
709 
710 		makeentry(entbuf, sizeof(entbuf), i, "dnssl");
711 		addr = (char *)agetstr(entbuf, &bp);
712 		if (addr == NULL)
713 			continue;
714 
715 		ELM_MALLOC(dnssl);
716 		TAILQ_INSERT_TAIL(&tmp->dnssl, dnssl, next);
717 		TAILQ_INIT(&dnssl->list);
718 
719 		for (ap = addr; ap - addr < (ssize_t)strlen(addr); ap += c+1) {
720 			c = strcspn(ap, ",");
721 			strncpy(abuf, ap, c);
722 			abuf[c] = '\0';
723 			ELM_MALLOC(dnsd);
724 			TAILQ_INSERT_TAIL(&dnssl->list, dnsd, next);
725 			dnsd->len = encode_domain(dnsd->domain, abuf);
726 		}
727 
728 		makeentry(entbuf, sizeof(entbuf), i, "dnsslltime");
729 		MAYHAVE(val64, entbuf, tmp->maxinterval * 3 / 2);
730 		if (val64 < tmp->maxinterval ||
731 		    val64 > tmp->maxinterval * 2)
732 		{
733 			syslog(LOG_ERR, "<%s> %s (%lld) on %s is invalid",
734 		    	     __func__, entbuf, (long long)val64, intface);
735 			goto errexit;
736 		}
737 		dnssl->lifetime = (uint32_t)val64;
738 
739 	}
740 
741 	TAILQ_FOREACH(rai, &ralist, next) {
742 		if (rai->ifindex == tmp->ifindex) {
743 			TAILQ_REMOVE(&ralist, rai, next);
744 			/* If we already have a leaving RA use that
745 			 * as this config hasn't been advertised */
746 			if (rai->leaving) {
747 				tmp->leaving = rai->leaving;
748 				free_rainfo(rai);
749 				rai = tmp->leaving;
750 				rai->leaving_for = tmp;
751 				break;
752 			}
753 			rai->lifetime = 0;
754 			TAILQ_FOREACH(rdnss, &rai->rdnss, next)
755 				rdnss->lifetime = 0;
756 			TAILQ_FOREACH(dnssl, &rai->dnssl, next)
757 				dnssl->lifetime = 0;
758 			rai->leaving_for = tmp;
759 			tmp->leaving = rai;
760 			rai->initcounter = MAX_INITIAL_RTR_ADVERTISEMENTS;
761 			rai->mininterval = MIN_DELAY_BETWEEN_RAS;
762 			rai->maxinterval = MIN_DELAY_BETWEEN_RAS;
763 			rai->leaving_adv = MAX_FINAL_RTR_ADVERTISEMENTS;
764 			if (rai->timer == NULL)
765 				rai->timer = rtadvd_add_timer(ra_timeout,
766 							      ra_timer_update,
767 							      rai, rai);
768 			ra_timer_update((void *)rai, &rai->timer->tm);
769 			rtadvd_set_timer(&rai->timer->tm, rai->timer);
770 			break;
771 		}
772 	}
773 
774 	/* okey */
775 	TAILQ_INSERT_TAIL(&ralist, tmp, next);
776 
777 	/* construct the sending packet */
778 	make_packet(tmp);
779 
780 	/* set timer */
781 	if (rai)
782 		return;
783 	tmp->timer = rtadvd_add_timer(ra_timeout, ra_timer_update,
784 				      tmp, tmp);
785 	ra_timer_set_short_delay(tmp);
786 
787 	return;
788 
789 errexit:
790 	if (exithard)
791 		exit(1);
792 	free_rainfo(tmp);
793 }
794 
795 void
get_prefix(struct rainfo * rai)796 get_prefix(struct rainfo *rai)
797 {
798 	struct ifaddrs *ifap, *ifa;
799 	struct prefix *pp;
800 	struct in6_addr *a;
801 	unsigned char *p, *ep, *m, *lim;
802 	char ntopbuf[INET6_ADDRSTRLEN];
803 
804 	if (getifaddrs(&ifap) < 0) {
805 		syslog(LOG_ERR,
806 		       "<%s> can't get interface addresses",
807 		       __func__);
808 		exit(1);
809 	}
810 
811 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
812 		int plen;
813 
814 		if (strcmp(ifa->ifa_name, rai->ifname) != 0)
815 			continue;
816 		if (ifa->ifa_addr->sa_family != AF_INET6)
817 			continue;
818 		a = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
819 		if (IN6_IS_ADDR_LINKLOCAL(a))
820 			continue;
821 		/* get prefix length */
822 		m = (unsigned char *)&((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr;
823 		lim = (unsigned char *)(ifa->ifa_netmask) + ifa->ifa_netmask->sa_len;
824 		plen = prefixlen(m, lim);
825 		if (plen <= 0 || plen > 128) {
826 			syslog(LOG_ERR, "<%s> failed to get prefixlen "
827 			       "or prefix is invalid",
828 			       __func__);
829 			exit(1);
830 		}
831 		if (plen == 128)	/* XXX */
832 			continue;
833 		if (find_prefix(rai, a, plen)) {
834 			/* ignore a duplicated prefix. */
835 			continue;
836 		}
837 
838 		/* allocate memory to store prefix info. */
839 		if ((pp = calloc(1, sizeof(*pp))) == NULL) {
840 			syslog(LOG_ERR,
841 			       "<%s> can't get allocate buffer for prefix",
842 			       __func__);
843 			exit(1);
844 		}
845 
846 		/* set prefix, sweep bits outside of prefixlen */
847 		pp->prefixlen = plen;
848 		memcpy(&pp->prefix, a, sizeof(*a));
849 		if (1)
850 		{
851 			p = (unsigned char *)&pp->prefix;
852 			ep = (unsigned char *)(&pp->prefix + 1);
853 			while (m < lim && p < ep)
854 				*p++ &= *m++;
855 			while (p < ep)
856 				*p++ = 0x00;
857 		}
858 	        if (!inet_ntop(AF_INET6, &pp->prefix, ntopbuf,
859 	            sizeof(ntopbuf))) {
860 			syslog(LOG_ERR, "<%s> inet_ntop failed", __func__);
861 			exit(1);
862 		}
863 		syslog(LOG_DEBUG,
864 		       "<%s> add %s/%d to prefix list on %s",
865 		       __func__, ntopbuf, pp->prefixlen, rai->ifname);
866 
867 		/* set other fields with protocol defaults */
868 		pp->validlifetime = DEF_ADVVALIDLIFETIME;
869 		pp->preflifetime = DEF_ADVPREFERREDLIFETIME;
870 		pp->onlinkflg = 1;
871 		pp->autoconfflg = 1;
872 		pp->origin = PREFIX_FROM_KERNEL;
873 		pp->rainfo = rai;
874 
875 		/* link into chain */
876 		TAILQ_INSERT_TAIL(&rai->prefix, pp, next);
877 		rai->pfxs++;
878 	}
879 
880 	freeifaddrs(ifap);
881 }
882 
883 static void
makeentry(char * buf,size_t len,int id,const char * string)884 makeentry(char *buf, size_t len, int id, const char *string)
885 {
886 
887 	if (id < 0)
888 		strlcpy(buf, string, len);
889 	else
890 		snprintf(buf, len, "%s%d", string, id);
891 }
892 
893 /*
894  * Add a prefix to the list of specified interface and reconstruct
895  * the outgoing packet.
896  * The prefix must not be in the list.
897  * XXX: other parameters of the prefix(e.g. lifetime) should be
898  * able to be specified.
899  */
900 static void
add_prefix(struct rainfo * rai,struct in6_prefixreq * ipr)901 add_prefix(struct rainfo *rai, struct in6_prefixreq *ipr)
902 {
903 	struct prefix *prefix;
904 	char ntopbuf[INET6_ADDRSTRLEN];
905 
906 	if ((prefix = calloc(1, sizeof(*prefix))) == NULL) {
907 		syslog(LOG_ERR, "<%s> memory allocation failed",
908 		       __func__);
909 		return;		/* XXX: error or exit? */
910 	}
911 	prefix->prefix = ipr->ipr_prefix.sin6_addr;
912 	prefix->prefixlen = ipr->ipr_plen;
913 	prefix->validlifetime = ipr->ipr_vltime;
914 	prefix->preflifetime = ipr->ipr_pltime;
915 	prefix->onlinkflg = ipr->ipr_raf_onlink;
916 	prefix->autoconfflg = ipr->ipr_raf_auto;
917 	prefix->origin = PREFIX_FROM_DYNAMIC;
918 
919 	prefix->rainfo = rai;
920 	TAILQ_INSERT_TAIL(&rai->prefix, prefix, next);
921 	rai->pfxs++;
922 
923 	syslog(LOG_DEBUG, "<%s> new prefix %s/%d was added on %s",
924 	       __func__, inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr,
925 				       ntopbuf, INET6_ADDRSTRLEN),
926 	       ipr->ipr_plen, rai->ifname);
927 
928 	/* free the previous packet */
929 	free(rai->ra_data);
930 	rai->ra_data = NULL;
931 
932 	/* reconstruct the packet */
933 	make_packet(rai);
934 }
935 
936 /*
937  * Delete a prefix to the list of specified interface and reconstruct
938  * the outgoing packet.
939  * The prefix must be in the list.
940  */
941 void
delete_prefix(struct prefix * prefix)942 delete_prefix(struct prefix *prefix)
943 {
944 	char ntopbuf[INET6_ADDRSTRLEN];
945 	struct rainfo *rai = prefix->rainfo;
946 
947 	TAILQ_REMOVE(&rai->prefix, prefix, next);
948 	rai->pfxs--;
949 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was deleted on %s",
950 	       __func__, inet_ntop(AF_INET6, &prefix->prefix,
951 				       ntopbuf, INET6_ADDRSTRLEN),
952 	       prefix->prefixlen, rai->ifname);
953 	rtadvd_remove_timer(&prefix->timer);
954 	free(prefix);
955 }
956 
957 void
invalidate_prefix(struct prefix * prefix)958 invalidate_prefix(struct prefix *prefix)
959 {
960 	char ntopbuf[INET6_ADDRSTRLEN];
961 	struct timespec timo;
962 	struct rainfo *rai = prefix->rainfo;
963 
964 	if (prefix->timer) {	/* sanity check */
965 		syslog(LOG_ERR,
966 		    "<%s> assumption failure: timer already exists",
967 		    __func__);
968 		exit(1);
969 	}
970 
971 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was invalidated on %s, "
972 	    "will expire in %ld seconds", __func__,
973 	    inet_ntop(AF_INET6, &prefix->prefix, ntopbuf, INET6_ADDRSTRLEN),
974 	    prefix->prefixlen, rai->ifname, (long)prefix_timo);
975 
976 	/* set the expiration timer */
977 	prefix->timer = rtadvd_add_timer(prefix_timeout, NULL, prefix, NULL);
978 	if (prefix->timer == NULL) {
979 		syslog(LOG_ERR, "<%s> failed to add a timer for a prefix. "
980 		    "remove the prefix", __func__);
981 		delete_prefix(prefix);
982 	}
983 	timo.tv_sec = prefix_timo;
984 	timo.tv_nsec = 0;
985 	rtadvd_set_timer(&timo, prefix->timer);
986 }
987 
988 static struct rtadvd_timer *
prefix_timeout(void * arg)989 prefix_timeout(void *arg)
990 {
991 	struct prefix *prefix = (struct prefix *)arg;
992 
993 	delete_prefix(prefix);
994 
995 	return(NULL);
996 }
997 
998 void
update_prefix(struct prefix * prefix)999 update_prefix(struct prefix * prefix)
1000 {
1001 	char ntopbuf[INET6_ADDRSTRLEN];
1002 	struct rainfo *rai = prefix->rainfo;
1003 
1004 	if (prefix->timer == NULL) { /* sanity check */
1005 		syslog(LOG_ERR,
1006 		    "<%s> assumption failure: timer does not exist",
1007 		    __func__);
1008 		exit(1);
1009 	}
1010 
1011 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was re-enabled on %s",
1012 	    __func__, inet_ntop(AF_INET6, &prefix->prefix, ntopbuf,
1013 	    INET6_ADDRSTRLEN), prefix->prefixlen, rai->ifname);
1014 
1015 	/* stop the expiration timer */
1016 	rtadvd_remove_timer(&prefix->timer);
1017 }
1018 
1019 /*
1020  * Try to get an in6_prefixreq contents for a prefix which matches
1021  * ipr->ipr_prefix and ipr->ipr_plen and belongs to
1022  * the interface whose name is ipr->ipr_name[].
1023  */
1024 static int
init_prefix(struct in6_prefixreq * ipr)1025 init_prefix(struct in6_prefixreq *ipr)
1026 {
1027 #if 0
1028 	int s;
1029 
1030 	if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
1031 		syslog(LOG_ERR, "<%s> socket: %m", __func__);
1032 		exit(1);
1033 	}
1034 
1035 	if (ioctl(s, SIOCGIFPREFIX_IN6, ipr) < 0) {
1036 		syslog(LOG_INFO, "<%s> ioctl:SIOCGIFPREFIX: %m", __func__);
1037 
1038 		ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
1039 		ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
1040 		ipr->ipr_raf_onlink = 1;
1041 		ipr->ipr_raf_auto = 1;
1042 		/* omit other field initialization */
1043 	}
1044 	else if (ipr->ipr_origin < PR_ORIG_RR) {
1045 		char ntopbuf[INET6_ADDRSTRLEN];
1046 
1047 		syslog(LOG_WARNING, "<%s> Added prefix(%s)'s origin %d is"
1048 		       "lower than PR_ORIG_RR(router renumbering)."
1049 		       "This should not happen if I am router", __func__,
1050 		       inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf,
1051 				 sizeof(ntopbuf)), ipr->ipr_origin);
1052 		close(s);
1053 		return 1;
1054 	}
1055 
1056 	close(s);
1057 	return 0;
1058 #else
1059 	ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
1060 	ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
1061 	ipr->ipr_raf_onlink = 1;
1062 	ipr->ipr_raf_auto = 1;
1063 	return 0;
1064 #endif
1065 }
1066 
1067 void
make_prefix(struct rainfo * rai,int ifindex,struct in6_addr * addr,int plen)1068 make_prefix(struct rainfo *rai, int ifindex, struct in6_addr *addr, int plen)
1069 {
1070 	struct in6_prefixreq ipr;
1071 
1072 	memset(&ipr, 0, sizeof(ipr));
1073 	if (if_indextoname(ifindex, ipr.ipr_name) == NULL) {
1074 		syslog(LOG_ERR, "<%s> Prefix added interface No.%d doesn't"
1075 		       "exist. This should not happen: %m", __func__,
1076 		       ifindex);
1077 		exit(1);
1078 	}
1079 	ipr.ipr_prefix.sin6_len = sizeof(ipr.ipr_prefix);
1080 	ipr.ipr_prefix.sin6_family = AF_INET6;
1081 	ipr.ipr_prefix.sin6_addr = *addr;
1082 	ipr.ipr_plen = plen;
1083 
1084 	if (init_prefix(&ipr))
1085 		return; /* init failed by some error */
1086 	add_prefix(rai, &ipr);
1087 }
1088 
1089 void
make_packet(struct rainfo * rainfo)1090 make_packet(struct rainfo *rainfo)
1091 {
1092 	size_t packlen, lladdroptlen = 0;
1093 	char *buf;
1094 	struct nd_router_advert *ra;
1095 	struct nd_opt_prefix_info *ndopt_pi;
1096 	struct nd_opt_mtu *ndopt_mtu;
1097 	struct prefix *pfx;
1098 	struct nd_opt_route_info *ndopt_rti;
1099 	struct rtinfo *rti;
1100 	struct nd_opt_rdnss *ndopt_rdnss;
1101 	struct rdnss *rdns;
1102 	struct rdnss_addr *rdnsa;
1103 	struct nd_opt_dnssl *ndopt_dnssl;
1104 	struct dnssl *dnsl;
1105 	struct dnssl_domain *dnsd;
1106 	size_t len, plen;
1107 
1108 	/* calculate total length */
1109 	packlen = sizeof(struct nd_router_advert);
1110 	if (rainfo->advlinkopt) {
1111 		if ((lladdroptlen = lladdropt_length(rainfo->sdl)) == 0) {
1112 			syslog(LOG_INFO,
1113 			       "<%s> link-layer address option has"
1114 			       " null length on %s.  Treat as not included.",
1115 			       __func__, rainfo->ifname);
1116 			rainfo->advlinkopt = 0;
1117 		}
1118 		packlen += lladdroptlen;
1119 	}
1120 	if (TAILQ_FIRST(&rainfo->prefix) != NULL)
1121 		packlen += sizeof(struct nd_opt_prefix_info) * rainfo->pfxs;
1122 	if (rainfo->linkmtu)
1123 		packlen += sizeof(struct nd_opt_mtu);
1124 	TAILQ_FOREACH(rti, &rainfo->route, next)
1125 		packlen += sizeof(struct nd_opt_route_info) +
1126 			   ((rti->prefixlen + 0x3f) >> 6) * 8;
1127 
1128 	TAILQ_FOREACH(rdns, &rainfo->rdnss, next) {
1129 		packlen += sizeof(struct nd_opt_rdnss);
1130 		TAILQ_FOREACH(rdnsa, &rdns->list, next)
1131 			packlen += sizeof(rdnsa->addr);
1132 	}
1133 	TAILQ_FOREACH(dnsl, &rainfo->dnssl, next) {
1134 		packlen += sizeof(struct nd_opt_dnssl);
1135 		len = 0;
1136 		TAILQ_FOREACH(dnsd, &dnsl->list, next)
1137 			len += dnsd->len;
1138 		len += len % 8 ? 8 - len % 8 : 0;
1139 		packlen += len;
1140 	}
1141 
1142 	/* allocate memory for the packet */
1143 	if ((buf = realloc(rainfo->ra_data, packlen)) == NULL) {
1144 		syslog(LOG_ERR,
1145 		       "<%s> can't get enough memory for an RA packet %m",
1146 		       __func__);
1147 		exit(1);
1148 	}
1149 	rainfo->ra_data = buf;
1150 	/* XXX: what if packlen > 576? */
1151 	rainfo->ra_datalen = packlen;
1152 #define CHECKLEN(size) \
1153 	do { \
1154 		if (buf + size > rainfo->ra_data + packlen) { \
1155 			syslog(LOG_ERR, \
1156 			    "<%s, %d> RA packet does not fit in %zu",\
1157 			    __func__, __LINE__, packlen); \
1158 			exit(1); \
1159 		} \
1160 	} while (/*CONSTCOND*/0)
1161 	/*
1162 	 * construct the packet
1163 	 */
1164 	CHECKLEN(sizeof(*ra));
1165 	ra = (struct nd_router_advert *)buf;
1166 	ra->nd_ra_type = ND_ROUTER_ADVERT;
1167 	ra->nd_ra_code = 0;
1168 	ra->nd_ra_cksum = 0;
1169 	ra->nd_ra_curhoplimit = (uint8_t)(0xff & rainfo->hoplimit);
1170 	ra->nd_ra_flags_reserved = 0; /* just in case */
1171 	/*
1172 	 * XXX: the router preference field, which is a 2-bit field, should be
1173 	 * initialized before other fields.
1174 	 */
1175 	ra->nd_ra_flags_reserved = 0xff & rainfo->rtpref;
1176 	ra->nd_ra_flags_reserved |=
1177 		rainfo->managedflg ? ND_RA_FLAG_MANAGED : 0;
1178 	ra->nd_ra_flags_reserved |=
1179 		rainfo->otherflg ? ND_RA_FLAG_OTHER : 0;
1180 	ra->nd_ra_router_lifetime = htons(rainfo->lifetime);
1181 	ra->nd_ra_reachable = htonl(rainfo->reachabletime);
1182 	ra->nd_ra_retransmit = htonl(rainfo->retranstimer);
1183 	buf += sizeof(*ra);
1184 
1185 	if (rainfo->advlinkopt) {
1186 		CHECKLEN(sizeof(struct nd_opt_hdr));
1187 		lladdropt_fill(rainfo->sdl, (struct nd_opt_hdr *)buf);
1188 		buf += lladdroptlen;
1189 	}
1190 
1191 	if (rainfo->linkmtu) {
1192 		CHECKLEN(sizeof(*ndopt_mtu));
1193 		ndopt_mtu = (struct nd_opt_mtu *)buf;
1194 		ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU;
1195 		ndopt_mtu->nd_opt_mtu_len = 1;
1196 		ndopt_mtu->nd_opt_mtu_reserved = 0;
1197 		ndopt_mtu->nd_opt_mtu_mtu = htonl(rainfo->linkmtu);
1198 		buf += sizeof(struct nd_opt_mtu);
1199 	}
1200 
1201 	TAILQ_FOREACH(pfx, &rainfo->prefix, next) {
1202 		uint32_t vltime, pltime;
1203 		struct timespec now;
1204 
1205 		CHECKLEN(sizeof(*ndopt_pi));
1206 		ndopt_pi = (struct nd_opt_prefix_info *)buf;
1207 		ndopt_pi->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
1208 		ndopt_pi->nd_opt_pi_len = 4;
1209 		ndopt_pi->nd_opt_pi_prefix_len = pfx->prefixlen;
1210 		ndopt_pi->nd_opt_pi_flags_reserved = 0;
1211 		if (pfx->onlinkflg)
1212 			ndopt_pi->nd_opt_pi_flags_reserved |=
1213 				ND_OPT_PI_FLAG_ONLINK;
1214 		if (pfx->autoconfflg)
1215 			ndopt_pi->nd_opt_pi_flags_reserved |=
1216 				ND_OPT_PI_FLAG_AUTO;
1217 		if (pfx->timer)
1218 			vltime = 0;
1219 		else {
1220 			if (pfx->vltimeexpire || pfx->pltimeexpire)
1221 				clock_gettime(CLOCK_MONOTONIC, &now);
1222 			if (pfx->vltimeexpire == 0)
1223 				vltime = pfx->validlifetime;
1224 			else
1225 				vltime = (pfx->vltimeexpire > now.tv_sec) ?
1226 				    pfx->vltimeexpire - now.tv_sec : 0;
1227 		}
1228 		if (pfx->timer)
1229 			pltime = 0;
1230 		else {
1231 			if (pfx->pltimeexpire == 0)
1232 				pltime = pfx->preflifetime;
1233 			else
1234 				pltime = (pfx->pltimeexpire > now.tv_sec) ?
1235 				    pfx->pltimeexpire - now.tv_sec : 0;
1236 		}
1237 		if (vltime < pltime) {
1238 			/*
1239 			 * this can happen if vltime is decrement but pltime
1240 			 * is not.
1241 			 */
1242 			pltime = vltime;
1243 		}
1244 		ndopt_pi->nd_opt_pi_valid_time = htonl(vltime);
1245 		ndopt_pi->nd_opt_pi_preferred_time = htonl(pltime);
1246 		ndopt_pi->nd_opt_pi_reserved2 = 0;
1247 		ndopt_pi->nd_opt_pi_prefix = pfx->prefix;
1248 
1249 		buf += sizeof(struct nd_opt_prefix_info);
1250 	}
1251 
1252 	TAILQ_FOREACH(rti, &rainfo->route, next) {
1253 		uint8_t psize = (rti->prefixlen + 0x3f) >> 6;
1254 
1255 		CHECKLEN(sizeof(*ndopt_rti));
1256 		ndopt_rti = (struct nd_opt_route_info *)buf;
1257 		ndopt_rti->nd_opt_rti_type = ND_OPT_ROUTE_INFO;
1258 		ndopt_rti->nd_opt_rti_len = 1 + psize;
1259 		ndopt_rti->nd_opt_rti_prefixlen = rti->prefixlen;
1260 		ndopt_rti->nd_opt_rti_flags = 0xff & rti->rtpref;
1261 		ndopt_rti->nd_opt_rti_lifetime = htonl(rti->ltime);
1262 		memcpy(ndopt_rti + 1, &rti->prefix, psize * 8);
1263 		buf += sizeof(struct nd_opt_route_info) + psize * 8;
1264 	}
1265 
1266 	TAILQ_FOREACH(rdns, &rainfo->rdnss, next) {
1267 		CHECKLEN(sizeof(*ndopt_rdnss));
1268 		ndopt_rdnss = (struct nd_opt_rdnss *)buf;
1269 		ndopt_rdnss->nd_opt_rdnss_type = ND_OPT_RDNSS;
1270 		ndopt_rdnss->nd_opt_rdnss_len = 1;
1271 		ndopt_rdnss->nd_opt_rdnss_reserved = 0;
1272 		ndopt_rdnss->nd_opt_rdnss_lifetime = htonl(rdns->lifetime);
1273 		buf += sizeof(*ndopt_rdnss);
1274 
1275 		TAILQ_FOREACH(rdnsa, &rdns->list, next) {
1276 			CHECKLEN(sizeof(rdnsa->addr));
1277 			memcpy(buf, &rdnsa->addr, sizeof(rdnsa->addr));
1278 			ndopt_rdnss->nd_opt_rdnss_len += 2;
1279 			buf += sizeof(rdnsa->addr);
1280 		}
1281 	}
1282 
1283 	TAILQ_FOREACH(dnsl, &rainfo->dnssl, next) {
1284 		CHECKLEN(sizeof(*ndopt_dnssl));
1285 		ndopt_dnssl = (struct nd_opt_dnssl *)buf;
1286 		ndopt_dnssl->nd_opt_dnssl_type = ND_OPT_DNSSL;
1287 		ndopt_dnssl->nd_opt_dnssl_len = 0;
1288 		ndopt_dnssl->nd_opt_dnssl_reserved = 0;
1289 		ndopt_dnssl->nd_opt_dnssl_lifetime = htonl(dnsl->lifetime);
1290 		buf += sizeof(*ndopt_dnssl);
1291 
1292 		TAILQ_FOREACH(dnsd, &dnsl->list, next) {
1293 			CHECKLEN(dnsd->len);
1294 			memcpy(buf, dnsd->domain, dnsd->len);
1295 			buf += dnsd->len;
1296 		}
1297 		/* Ensure our length is padded correctly */
1298 		len = buf - (char *)ndopt_dnssl;
1299 		plen = len % 8 ? 8 - len % 8 : 0;
1300 		CHECKLEN(plen);
1301 		memset(buf, 0, plen);
1302 		buf += plen;
1303 		ndopt_dnssl->nd_opt_dnssl_len = (len + plen) / 8;
1304 	}
1305 	memset(buf, 0, packlen - (buf - rainfo->ra_data));
1306 }
1307 
1308 static int
getinet6sysctl(int code)1309 getinet6sysctl(int code)
1310 {
1311 	const int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, code };
1312 	int value;
1313 	size_t size;
1314 
1315 	size = sizeof(value);
1316 	if (sysctl(mib, __arraycount(mib), &value, &size, NULL, 0)
1317 	    < 0) {
1318 		syslog(LOG_ERR, "<%s>: failed to get ip6 sysctl(%d): %m",
1319 		       __func__, code);
1320 		return -1;
1321 	}
1322 	else
1323 		return value;
1324 }
1325