xref: /freebsd/usr.sbin/rtadvd/config.c (revision eda14cbc264d6969b02f2b1994cef11148e914f1)
1 /*	$FreeBSD$	*/
2 /*	$KAME: config.c,v 1.84 2003/08/05 12:34:23 itojun Exp $	*/
3 
4 /*-
5  * SPDX-License-Identifier: BSD-3-Clause
6  *
7  * Copyright (C) 1998 WIDE Project.
8  * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the project nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/param.h>
37 #include <sys/ioctl.h>
38 #include <sys/socket.h>
39 
40 #include <net/if.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 #include <netinet6/nd6.h>
50 
51 #include <arpa/inet.h>
52 
53 #include <stdio.h>
54 #include <syslog.h>
55 #include <errno.h>
56 #include <inttypes.h>
57 #include <netdb.h>
58 #include <string.h>
59 #include <search.h>
60 #include <stdlib.h>
61 #include <time.h>
62 #include <unistd.h>
63 #include <ifaddrs.h>
64 
65 #include "rtadvd.h"
66 #include "advcap.h"
67 #include "timer.h"
68 #include "if.h"
69 #include "config.h"
70 
71 /* label of tcapcode + number + domain name + zero octet */
72 static char entbuf[10 + 3 + NI_MAXHOST + 1];
73 static char oentbuf[10 + 3 + NI_MAXHOST + 1];
74 static char abuf[DNAME_LABELENC_MAXLEN];
75 
76 static time_t prefix_timo = (60 * 120);	/* 2 hours.
77 					 * XXX: should be configurable. */
78 
79 static struct rtadvd_timer *prefix_timeout(void *);
80 static void makeentry(char *, size_t, int, const char *);
81 static ssize_t dname_labelenc(char *, const char *);
82 
83 /* Encode domain name label encoding in RFC 1035 Section 3.1 */
84 static ssize_t
85 dname_labelenc(char *dst, const char *src)
86 {
87 	char *dst_origin;
88 	char *p;
89 	size_t len;
90 
91 	dst_origin = dst;
92 	len = strlen(src);
93 
94 	if (len + len / 64 + 1 + 1 > DNAME_LABELENC_MAXLEN)
95 		return (-1);
96 	/* Length fields per 63 octets + '\0' (<= DNAME_LABELENC_MAXLEN) */
97 	memset(dst, 0, len + len / 64 + 1 + 1);
98 
99 	syslog(LOG_DEBUG, "<%s> labelenc = %s", __func__, src);
100 	while (src && (len = strlen(src)) != 0) {
101 		/* Put a length field with 63 octet limitation first. */
102 		p = strchr(src, '.');
103 		if (p == NULL)
104 			*dst = len = MIN(63, len);
105 		else
106 			*dst = len = MIN(63, p - src);
107 		if (dst + 1 + len < dst_origin + DNAME_LABELENC_MAXLEN)
108 			dst++;
109 		else
110 			return (-1);
111 		/* Copy 63 octets at most. */
112 		memcpy(dst, src, len);
113 		dst += len;
114 		if (p == NULL) /* the last label */
115 			break;
116 		src = p + 1;
117 	}
118 	/* Always need a 0-length label at the tail. */
119 	*dst++ = '\0';
120 
121 	syslog(LOG_DEBUG, "<%s> labellen = %td", __func__, dst - dst_origin);
122 	return (dst - dst_origin);
123 }
124 
125 #define	MUSTHAVE(var, cap)						\
126     do {								\
127 	int64_t t;							\
128 	if ((t = agetnum(cap)) < 0) {					\
129 		fprintf(stderr, "rtadvd: need %s for interface %s\n",	\
130 			cap, intface);					\
131 		exit(1);						\
132 	}								\
133 	var = t;							\
134      } while (0)
135 
136 #define	MAYHAVE(var, cap, def)						\
137      do {								\
138 	if ((var = agetnum(cap)) < 0)					\
139 		var = def;						\
140      } while (0)
141 
142 int
143 loadconfig_index(int idx)
144 {
145 	char ifname[IFNAMSIZ];
146 
147 	syslog(LOG_DEBUG, "<%s> enter", __func__);
148 
149 	if (if_indextoname(idx, ifname) != NULL)
150 		return (loadconfig_ifname(ifname));
151 	else
152 		return (1);
153 }
154 
155 int
156 loadconfig_ifname(char *ifname)
157 {
158 	struct ifinfo *ifi;
159 
160 	syslog(LOG_DEBUG, "<%s> enter", __func__);
161 
162 	update_ifinfo(&ifilist, UPDATE_IFINFO_ALL);
163 	TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
164 		/* NULL means all IFs will be processed. */
165 		if (ifname != NULL &&
166 		    strcmp(ifi->ifi_ifname, ifname) != 0)
167 			continue;
168 
169 		if (!ifi->ifi_persist) {
170 			syslog(LOG_INFO,
171 			    "<%s> %s is not a target interface.  "
172 			    "Ignored at this moment.", __func__,
173 			    ifi->ifi_ifname);
174 			continue;
175 
176 		}
177 		if (ifi->ifi_ifindex == 0) {
178 			syslog(LOG_ERR,
179 			    "<%s> %s not found.  "
180 			    "Ignored at this moment.", __func__,
181 			    ifi->ifi_ifname);
182 			continue;
183 		}
184 		if (getconfig(ifi) == NULL) {
185 			syslog(LOG_ERR,
186 			    "<%s> invalid configuration for %s.  "
187 			    "Ignored at this moment.", __func__,
188 			    ifi->ifi_ifname);
189 			continue;
190 		}
191 	}
192 	return (0);
193 }
194 
195 int
196 rm_ifinfo_index(int idx)
197 {
198 	struct ifinfo *ifi;
199 
200 	ifi = if_indextoifinfo(idx);
201 	if (ifi == NULL) {
202 		syslog(LOG_ERR, "<%s>: ifinfo not found (idx=%d)",
203 		    __func__, idx);
204 		return (-1);
205 	}
206 
207 	return (rm_ifinfo(ifi));
208 }
209 
210 int
211 rm_ifinfo(struct ifinfo *ifi)
212 {
213 	int error;
214 
215 	syslog(LOG_DEBUG, "<%s> enter (%s).", __func__, ifi->ifi_ifname);
216 	switch (ifi->ifi_state) {
217 	case IFI_STATE_UNCONFIGURED:
218 		return (0);
219 		break;
220 	default:
221 		ifi->ifi_state = IFI_STATE_UNCONFIGURED;
222 		syslog(LOG_DEBUG,
223 		    "<%s> ifname=%s marked as UNCONFIGURED.",
224 		    __func__, ifi->ifi_ifname);
225 
226 		/* XXX: No MC leaving here because index is disappeared */
227 
228 		/* Inactivate timer */
229 		rtadvd_remove_timer(ifi->ifi_ra_timer);
230 		ifi->ifi_ra_timer = NULL;
231 		break;
232 	}
233 
234 	/* clean up ifi */
235 	if (!ifi->ifi_persist) {
236 		TAILQ_REMOVE(&ifilist, ifi, ifi_next);
237 		syslog(LOG_DEBUG, "<%s>: ifinfo (idx=%d) removed.",
238 		    __func__, ifi->ifi_ifindex);
239 	} else {
240 		/* recreate an empty entry */
241 		update_persist_ifinfo(&ifilist, ifi->ifi_ifname);
242 		syslog(LOG_DEBUG, "<%s>: ifname=%s is persistent.",
243 		    __func__, ifi->ifi_ifname);
244 	}
245 
246 	/* clean up rai if any */
247 	switch (ifi->ifi_state) {
248 	case IFI_STATE_CONFIGURED:
249 		if (ifi->ifi_rainfo != NULL) {
250 			error = rm_rainfo(ifi->ifi_rainfo);
251 			if (error)
252 				return (error);
253 			ifi->ifi_rainfo = NULL;
254 		}
255 		break;
256 	case IFI_STATE_TRANSITIVE:
257 		if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) {
258 			if (ifi->ifi_rainfo != NULL) {
259 				error = rm_rainfo(ifi->ifi_rainfo);
260 				if (error)
261 					return (error);
262 				ifi->ifi_rainfo = NULL;
263 				ifi->ifi_rainfo_trans = NULL;
264 			}
265 		} else {
266 			if (ifi->ifi_rainfo != NULL) {
267 				error = rm_rainfo(ifi->ifi_rainfo);
268 				if (error)
269 					return (error);
270 				ifi->ifi_rainfo = NULL;
271 			}
272 			if (ifi->ifi_rainfo_trans != NULL) {
273 				error = rm_rainfo(ifi->ifi_rainfo_trans);
274 				if (error)
275 					return (error);
276 				ifi->ifi_rainfo_trans = NULL;
277 			}
278 		}
279 	}
280 
281 	syslog(LOG_DEBUG, "<%s> leave (%s).", __func__, ifi->ifi_ifname);
282 	if (!ifi->ifi_persist)
283 		free(ifi);
284 	return (0);
285 }
286 
287 int
288 rm_rainfo(struct rainfo *rai)
289 {
290 	struct prefix *pfx;
291 	struct soliciter *sol;
292 	struct rdnss *rdn;
293 	struct rdnss_addr *rdna;
294 	struct dnssl *dns;
295 	struct rtinfo *rti;
296 
297 	syslog(LOG_DEBUG, "<%s>: enter",  __func__);
298 
299 	TAILQ_REMOVE(&railist, rai, rai_next);
300 	if (rai->rai_ifinfo != NULL)
301 		syslog(LOG_DEBUG, "<%s>: rainfo (idx=%d) removed.",
302 		    __func__, rai->rai_ifinfo->ifi_ifindex);
303 
304 	if (rai->rai_ra_data != NULL)
305 		free(rai->rai_ra_data);
306 
307 	while ((pfx = TAILQ_FIRST(&rai->rai_prefix)) != NULL)
308 		delete_prefix(pfx);
309 	while ((sol = TAILQ_FIRST(&rai->rai_soliciter)) != NULL) {
310 		TAILQ_REMOVE(&rai->rai_soliciter, sol, sol_next);
311 		free(sol);
312 	}
313 	while ((rdn = TAILQ_FIRST(&rai->rai_rdnss)) != NULL) {
314 		TAILQ_REMOVE(&rai->rai_rdnss, rdn, rd_next);
315 		while ((rdna = TAILQ_FIRST(&rdn->rd_list)) != NULL) {
316 			TAILQ_REMOVE(&rdn->rd_list, rdna, ra_next);
317 			free(rdna);
318 		}
319 		free(rdn);
320 	}
321 	while ((dns = TAILQ_FIRST(&rai->rai_dnssl)) != NULL) {
322 		TAILQ_REMOVE(&rai->rai_dnssl, dns, dn_next);
323 		free(dns);
324 	}
325 	while ((rti = TAILQ_FIRST(&rai->rai_route)) != NULL) {
326 		TAILQ_REMOVE(&rai->rai_route, rti, rti_next);
327 		free(rti);
328 	}
329 	free(rai);
330 	syslog(LOG_DEBUG, "<%s>: leave",  __func__);
331 
332 	return (0);
333 }
334 
335 struct ifinfo *
336 getconfig(struct ifinfo *ifi)
337 {
338 	int stat, i;
339 	int error;
340 	char tbuf[BUFSIZ];
341 	struct rainfo *rai;
342 	struct rainfo *rai_old;
343 	int32_t val;
344 	int64_t val64;
345 	char buf[BUFSIZ];
346 	char *bp = buf;
347 	char *addr, *flagstr;
348 
349 	if (ifi == NULL)	/* if does not exist */
350 		return (NULL);
351 
352 	if (ifi->ifi_state == IFI_STATE_TRANSITIVE &&
353 	    ifi->ifi_rainfo == NULL) {
354 		syslog(LOG_INFO, "<%s> %s is shutting down.  Skipped.",
355 		    __func__, ifi->ifi_ifname);
356 		return (NULL);
357 	}
358 
359 	if ((stat = agetent(tbuf, ifi->ifi_ifname)) <= 0) {
360 		memset(tbuf, 0, sizeof(tbuf));
361 		syslog(LOG_INFO,
362 		    "<%s> %s isn't defined in the configuration file"
363 		    " or the configuration file doesn't exist."
364 		    " Treat it as default",
365 		     __func__, ifi->ifi_ifname);
366 	}
367 
368 	ELM_MALLOC(rai, exit(1));
369 	TAILQ_INIT(&rai->rai_prefix);
370 	TAILQ_INIT(&rai->rai_route);
371 	TAILQ_INIT(&rai->rai_rdnss);
372 	TAILQ_INIT(&rai->rai_dnssl);
373 	TAILQ_INIT(&rai->rai_soliciter);
374 	rai->rai_ifinfo = ifi;
375 
376 	/* gather on-link prefixes from the network interfaces. */
377 	if (agetflag("noifprefix"))
378 		rai->rai_advifprefix = 0;
379 	else
380 		rai->rai_advifprefix = 1;
381 
382 	/* get interface information */
383 	if (agetflag("nolladdr"))
384 		rai->rai_advlinkopt = 0;
385 	else
386 		rai->rai_advlinkopt = 1;
387 	if (rai->rai_advlinkopt) {
388 		if (ifi->ifi_sdl.sdl_type == 0) {
389 			syslog(LOG_ERR,
390 			    "<%s> can't get information of %s",
391 			    __func__, ifi->ifi_ifname);
392 			goto getconfig_free_rai;
393 		}
394 	}
395 
396 	/*
397 	 * set router configuration variables.
398 	 */
399 	MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL);
400 	if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) {
401 		syslog(LOG_ERR,
402 		    "<%s> maxinterval (%" PRIu32 ") on %s is invalid "
403 		    "(must be between %u and %u)", __func__, val,
404 		    ifi->ifi_ifname, MIN_MAXINTERVAL, MAX_MAXINTERVAL);
405 		goto getconfig_free_rai;
406 	}
407 	rai->rai_maxinterval = (uint16_t)val;
408 
409 	MAYHAVE(val, "mininterval", rai->rai_maxinterval/3);
410 	if ((uint16_t)val < MIN_MININTERVAL ||
411 	    (uint16_t)val > (rai->rai_maxinterval * 3) / 4) {
412 		syslog(LOG_ERR,
413 		    "<%s> mininterval (%" PRIu32 ") on %s is invalid "
414 		    "(must be between %d and %d)",
415 		    __func__, val, ifi->ifi_ifname, MIN_MININTERVAL,
416 		    (rai->rai_maxinterval * 3) / 4);
417 		goto getconfig_free_rai;
418 	}
419 	rai->rai_mininterval = (uint16_t)val;
420 
421 	MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT);
422 	rai->rai_hoplimit = val & 0xff;
423 
424 	if ((flagstr = (char *)agetstr("raflags", &bp))) {
425 		val = 0;
426 		if (strchr(flagstr, 'm'))
427 			val |= ND_RA_FLAG_MANAGED;
428 		if (strchr(flagstr, 'o'))
429 			val |= ND_RA_FLAG_OTHER;
430 		if (strchr(flagstr, 'h'))
431 			val |= ND_RA_FLAG_RTPREF_HIGH;
432 		if (strchr(flagstr, 'l')) {
433 			if ((val & ND_RA_FLAG_RTPREF_HIGH)) {
434 				syslog(LOG_ERR, "<%s> the \'h\' and \'l\'"
435 				    " router flags are exclusive", __func__);
436 				goto getconfig_free_rai;
437 			}
438 			val |= ND_RA_FLAG_RTPREF_LOW;
439 		}
440 #ifdef DRAFT_IETF_6MAN_IPV6ONLY_FLAG
441 		if (strchr(flagstr, 'S'))
442 			val |= ND_RA_FLAG_IPV6_ONLY;
443 #endif
444 	} else
445 		MAYHAVE(val, "raflags", 0);
446 
447 	rai->rai_managedflg = val & ND_RA_FLAG_MANAGED;
448 	rai->rai_otherflg = val & ND_RA_FLAG_OTHER;
449 #ifndef ND_RA_FLAG_RTPREF_MASK
450 #define ND_RA_FLAG_RTPREF_MASK	0x18 /* 00011000 */
451 #define ND_RA_FLAG_RTPREF_RSV	0x10 /* 00010000 */
452 #endif
453 	rai->rai_rtpref = val & ND_RA_FLAG_RTPREF_MASK;
454 	if (rai->rai_rtpref == ND_RA_FLAG_RTPREF_RSV) {
455 		syslog(LOG_ERR, "<%s> invalid router preference (%02x) on %s",
456 		    __func__, rai->rai_rtpref, ifi->ifi_ifname);
457 		goto getconfig_free_rai;
458 	}
459 #ifdef DRAFT_IETF_6MAN_IPV6ONLY_FLAG
460 	rai->rai_ipv6onlyflg = val & ND_RA_FLAG_IPV6_ONLY;
461 #endif
462 
463 	MAYHAVE(val, "rltime", rai->rai_maxinterval * 3);
464 	if ((uint16_t)val && ((uint16_t)val < rai->rai_maxinterval ||
465 	    (uint16_t)val > MAXROUTERLIFETIME)) {
466 		syslog(LOG_ERR,
467 		    "<%s> router lifetime (%" PRIu32 ") on %s is invalid "
468 		    "(must be 0 or between %d and %d)",
469 		    __func__, val, ifi->ifi_ifname, rai->rai_maxinterval,
470 		    MAXROUTERLIFETIME);
471 		goto getconfig_free_rai;
472 	}
473 	rai->rai_lifetime = val & 0xffff;
474 
475 	MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME);
476 	if (val < 0 || val > MAXREACHABLETIME) {
477 		syslog(LOG_ERR,
478 		    "<%s> reachable time (%" PRIu32 ") on %s is invalid "
479 		    "(must be no greater than %d)",
480 		    __func__, val, ifi->ifi_ifname, MAXREACHABLETIME);
481 		goto getconfig_free_rai;
482 	}
483 	rai->rai_reachabletime = (uint32_t)val;
484 
485 	MAYHAVE(val64, "retrans", DEF_ADVRETRANSTIMER);
486 	if (val64 < 0 || val64 > 0xffffffff) {
487 		syslog(LOG_ERR, "<%s> retrans time (%" PRIu64 ") on %s out of range",
488 		    __func__, val64, ifi->ifi_ifname);
489 		goto getconfig_free_rai;
490 	}
491 	rai->rai_retranstimer = (uint32_t)val64;
492 
493 	if (agetnum("hapref") != -1 || agetnum("hatime") != -1) {
494 		syslog(LOG_ERR,
495 		    "<%s> mobile-ip6 configuration not supported",
496 		    __func__);
497 		goto getconfig_free_rai;
498 	}
499 	/* prefix information */
500 
501 	/*
502 	 * This is an implementation specific parameter to consider
503 	 * link propagation delays and poorly synchronized clocks when
504 	 * checking consistency of advertised lifetimes.
505 	 */
506 	MAYHAVE(val, "clockskew", 0);
507 	rai->rai_clockskew = val;
508 
509 	rai->rai_pfxs = 0;
510 	for (i = -1; i < MAXPREFIX; i++) {
511 		struct prefix *pfx;
512 
513 		makeentry(entbuf, sizeof(entbuf), i, "addr");
514 		addr = (char *)agetstr(entbuf, &bp);
515 		if (addr == NULL)
516 			continue;
517 
518 		/* allocate memory to store prefix information */
519 		ELM_MALLOC(pfx, exit(1));
520 		pfx->pfx_rainfo = rai;
521 		pfx->pfx_origin = PREFIX_FROM_CONFIG;
522 
523 		if (inet_pton(AF_INET6, addr, &pfx->pfx_prefix) != 1) {
524 			syslog(LOG_ERR,
525 			    "<%s> inet_pton failed for %s",
526 			    __func__, addr);
527 			goto getconfig_free_pfx;
528 		}
529 		if (IN6_IS_ADDR_MULTICAST(&pfx->pfx_prefix)) {
530 			syslog(LOG_ERR,
531 			    "<%s> multicast prefix (%s) must "
532 			    "not be advertised on %s",
533 			    __func__, addr, ifi->ifi_ifname);
534 			goto getconfig_free_pfx;
535 		}
536 		if (IN6_IS_ADDR_LINKLOCAL(&pfx->pfx_prefix))
537 			syslog(LOG_NOTICE,
538 			    "<%s> link-local prefix (%s) will be"
539 			    " advertised on %s",
540 			    __func__, addr, ifi->ifi_ifname);
541 
542 		makeentry(entbuf, sizeof(entbuf), i, "prefixlen");
543 		MAYHAVE(val, entbuf, 64);
544 		if (val < 0 || val > 128) {
545 			syslog(LOG_ERR, "<%s> prefixlen (%" PRIu32 ") for %s "
546 			    "on %s out of range",
547 			    __func__, val, addr, ifi->ifi_ifname);
548 			goto getconfig_free_pfx;
549 		}
550 		pfx->pfx_prefixlen = (int)val;
551 
552 		makeentry(entbuf, sizeof(entbuf), i, "pinfoflags");
553 		if ((flagstr = (char *)agetstr(entbuf, &bp))) {
554 			val = 0;
555 			if (strchr(flagstr, 'l'))
556 				val |= ND_OPT_PI_FLAG_ONLINK;
557 			if (strchr(flagstr, 'a'))
558 				val |= ND_OPT_PI_FLAG_AUTO;
559 		} else {
560 			MAYHAVE(val, entbuf,
561 			    (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO));
562 		}
563 		pfx->pfx_onlinkflg = val & ND_OPT_PI_FLAG_ONLINK;
564 		pfx->pfx_autoconfflg = val & ND_OPT_PI_FLAG_AUTO;
565 
566 		makeentry(entbuf, sizeof(entbuf), i, "vltime");
567 		MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
568 		if (val64 < 0 || val64 > 0xffffffff) {
569 			syslog(LOG_ERR, "<%s> vltime (%" PRIu64 ") for "
570 			    "%s/%d on %s is out of range",
571 			    __func__, val64,
572 			    addr, pfx->pfx_prefixlen, ifi->ifi_ifname);
573 			goto getconfig_free_pfx;
574 		}
575 		pfx->pfx_validlifetime = (uint32_t)val64;
576 
577 		makeentry(entbuf, sizeof(entbuf), i, "vltimedecr");
578 		if (agetflag(entbuf)) {
579 			struct timespec now;
580 
581 			clock_gettime(CLOCK_MONOTONIC_FAST, &now);
582 			pfx->pfx_vltimeexpire =
583 				now.tv_sec + pfx->pfx_validlifetime;
584 		}
585 
586 		makeentry(entbuf, sizeof(entbuf), i, "pltime");
587 		MAYHAVE(val64, entbuf, DEF_ADVPREFERREDLIFETIME);
588 		if (val64 < 0 || val64 > 0xffffffff) {
589 			syslog(LOG_ERR,
590 			    "<%s> pltime (%" PRIu64 ") for %s/%d on %s "
591 			    "is out of range",
592 			    __func__, val64,
593 			    addr, pfx->pfx_prefixlen, ifi->ifi_ifname);
594 			goto getconfig_free_pfx;
595 		}
596 		pfx->pfx_preflifetime = (uint32_t)val64;
597 
598 		makeentry(entbuf, sizeof(entbuf), i, "pltimedecr");
599 		if (agetflag(entbuf)) {
600 			struct timespec now;
601 
602 			clock_gettime(CLOCK_MONOTONIC_FAST, &now);
603 			pfx->pfx_pltimeexpire =
604 			    now.tv_sec + pfx->pfx_preflifetime;
605 		}
606 		/* link into chain */
607 		TAILQ_INSERT_TAIL(&rai->rai_prefix, pfx, pfx_next);
608 		rai->rai_pfxs++;
609 		continue;
610 getconfig_free_pfx:
611 		free(pfx);
612 	}
613 	if (rai->rai_advifprefix && rai->rai_pfxs == 0)
614 		get_prefix(rai);
615 
616 	MAYHAVE(val64, "mtu", 0);
617 	if (val < 0 || val64 > 0xffffffff) {
618 		syslog(LOG_ERR,
619 		    "<%s> mtu (%" PRIu64 ") on %s out of range",
620 		    __func__, val64, ifi->ifi_ifname);
621 		goto getconfig_free_rai;
622 	}
623 	rai->rai_linkmtu = (uint32_t)val64;
624 	if (rai->rai_linkmtu == 0) {
625 		char *mtustr;
626 
627 		if ((mtustr = (char *)agetstr("mtu", &bp)) &&
628 		    strcmp(mtustr, "auto") == 0)
629 			rai->rai_linkmtu = ifi->ifi_phymtu;
630 	}
631 	else if (rai->rai_linkmtu < IPV6_MMTU ||
632 	    rai->rai_linkmtu > ifi->ifi_phymtu) {
633 		syslog(LOG_ERR,
634 		    "<%s> advertised link mtu (%" PRIu32 ") on %s is invalid (must "
635 		    "be between least MTU (%d) and physical link MTU (%d)",
636 		    __func__, rai->rai_linkmtu, ifi->ifi_ifname,
637 		    IPV6_MMTU, ifi->ifi_phymtu);
638 		goto getconfig_free_rai;
639 	}
640 
641 #ifdef SIOCSIFINFO_IN6
642 	{
643 		struct in6_ndireq ndi;
644 		int s;
645 
646 		if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
647 			syslog(LOG_ERR, "<%s> socket: %s", __func__,
648 			    strerror(errno));
649 			exit(1);
650 		}
651 		memset(&ndi, 0, sizeof(ndi));
652 		strlcpy(ndi.ifname, ifi->ifi_ifname, sizeof(ndi.ifname));
653 		if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&ndi) < 0)
654 			syslog(LOG_INFO, "<%s> ioctl:SIOCGIFINFO_IN6 at %s: %s",
655 			    __func__, ifi->ifi_ifname, strerror(errno));
656 
657 		/* reflect the RA info to the host variables in kernel */
658 		ndi.ndi.chlim = rai->rai_hoplimit;
659 		ndi.ndi.retrans = rai->rai_retranstimer;
660 		ndi.ndi.basereachable = rai->rai_reachabletime;
661 		if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&ndi) < 0)
662 			syslog(LOG_INFO, "<%s> ioctl:SIOCSIFINFO_IN6 at %s: %s",
663 			    __func__, ifi->ifi_ifname, strerror(errno));
664 
665 		close(s);
666 	}
667 #endif
668 
669 	/* route information */
670 	rai->rai_routes = 0;
671 	for (i = -1; i < MAXROUTE; i++) {
672 		struct rtinfo *rti;
673 
674 		makeentry(entbuf, sizeof(entbuf), i, "rtprefix");
675 		addr = (char *)agetstr(entbuf, &bp);
676 		if (addr == NULL) {
677 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrprefix");
678 			addr = (char *)agetstr(oentbuf, &bp);
679 			if (addr)
680 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
681 				    oentbuf, entbuf);
682 		}
683 		if (addr == NULL)
684 			continue;
685 
686 		/* allocate memory to store prefix information */
687 		ELM_MALLOC(rti, exit(1));
688 
689 		if (inet_pton(AF_INET6, addr, &rti->rti_prefix) != 1) {
690 			syslog(LOG_ERR, "<%s> inet_pton failed for %s",
691 			    __func__, addr);
692 			goto getconfig_free_rti;
693 		}
694 #if 0
695 		/*
696 		 * XXX: currently there's no restriction in route information
697 		 * prefix according to
698 		 * draft-ietf-ipngwg-router-selection-00.txt.
699 		 * However, I think the similar restriction be necessary.
700 		 */
701 		MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
702 		if (IN6_IS_ADDR_MULTICAST(&rti->prefix)) {
703 			syslog(LOG_ERR,
704 			    "<%s> multicast route (%s) must "
705 			    "not be advertised on %s",
706 			    __func__, addr, ifi->ifi_ifname);
707 			goto getconfig_free_rti;
708 		}
709 		if (IN6_IS_ADDR_LINKLOCAL(&rti->prefix)) {
710 			syslog(LOG_NOTICE,
711 			    "<%s> link-local route (%s) will "
712 			    "be advertised on %s",
713 			    __func__, addr, ifi->ifi_ifname);
714 			goto getconfig_free_rti;
715 		}
716 #endif
717 
718 		makeentry(entbuf, sizeof(entbuf), i, "rtplen");
719 		/* XXX: 256 is a magic number for compatibility check. */
720 		MAYHAVE(val, entbuf, 256);
721 		if (val == 256) {
722 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrplen");
723 			MAYHAVE(val, oentbuf, 256);
724 			if (val != 256)
725 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
726 				    oentbuf, entbuf);
727 			else
728 				val = 64;
729 		}
730 		if (val < 0 || val > 128) {
731 			syslog(LOG_ERR, "<%s> prefixlen (%" PRIu32 ") for %s on %s "
732 			    "out of range",
733 			    __func__, val, addr, ifi->ifi_ifname);
734 			goto getconfig_free_rti;
735 		}
736 		rti->rti_prefixlen = (int)val;
737 
738 		makeentry(entbuf, sizeof(entbuf), i, "rtflags");
739 		if ((flagstr = (char *)agetstr(entbuf, &bp))) {
740 			val = 0;
741 			if (strchr(flagstr, 'h'))
742 				val |= ND_RA_FLAG_RTPREF_HIGH;
743 			if (strchr(flagstr, 'l')) {
744 				if ((val & ND_RA_FLAG_RTPREF_HIGH)) {
745 					syslog(LOG_ERR,
746 					    "<%s> the \'h\' and \'l\' route"
747 					    " preferences are exclusive",
748 					    __func__);
749 					goto getconfig_free_rti;
750 				}
751 				val |= ND_RA_FLAG_RTPREF_LOW;
752 			}
753 		} else
754 			MAYHAVE(val, entbuf, 256); /* XXX */
755 		if (val == 256) {
756 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrflags");
757 			MAYHAVE(val, oentbuf, 256);
758 			if (val != 256) {
759 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
760 				    oentbuf, entbuf);
761 			} else
762 				val = 0;
763 		}
764 		rti->rti_rtpref = val & ND_RA_FLAG_RTPREF_MASK;
765 		if (rti->rti_rtpref == ND_RA_FLAG_RTPREF_RSV) {
766 			syslog(LOG_ERR, "<%s> invalid route preference (%02x) "
767 			    "for %s/%d on %s",
768 			    __func__, rti->rti_rtpref, addr,
769 			    rti->rti_prefixlen, ifi->ifi_ifname);
770 			goto getconfig_free_rti;
771 		}
772 
773 		/*
774 		 * Since the spec does not a default value, we should make
775 		 * this entry mandatory.  However, FreeBSD 4.4 has shipped
776 		 * with this field being optional, we use the router lifetime
777 		 * as an ad-hoc default value with a warning message.
778 		 */
779 		makeentry(entbuf, sizeof(entbuf), i, "rtltime");
780 		MAYHAVE(val64, entbuf, -1);
781 		if (val64 == -1) {
782 			makeentry(oentbuf, sizeof(oentbuf), i, "rtrltime");
783 			MAYHAVE(val64, oentbuf, -1);
784 			if (val64 != -1)
785 				fprintf(stderr, "%s was obsoleted.  Use %s.\n",
786 				    oentbuf, entbuf);
787 			else {
788 				fprintf(stderr, "%s should be specified "
789 				    "for interface %s.\n", entbuf,
790 				    ifi->ifi_ifname);
791 				val64 = rai->rai_lifetime;
792 			}
793 		}
794 		if (val64 < 0 || val64 > 0xffffffff) {
795 			syslog(LOG_ERR, "<%s> route lifetime (%" PRIu64 ") for "
796 			    "%s/%d on %s out of range", __func__,
797 			    val64, addr, rti->rti_prefixlen,
798 			    ifi->ifi_ifname);
799 			goto getconfig_free_rti;
800 		}
801 		rti->rti_ltime = (uint32_t)val64;
802 
803 		/* link into chain */
804 		TAILQ_INSERT_TAIL(&rai->rai_route, rti, rti_next);
805 		rai->rai_routes++;
806 		continue;
807 getconfig_free_rti:
808 		free(rti);
809 	}
810 
811 	/* DNS server and DNS search list information */
812 	for (i = -1; i < MAXRDNSSENT ; i++) {
813 		struct rdnss *rdn;
814 		struct rdnss_addr *rdna;
815 		char *ap;
816 		int c;
817 
818 		makeentry(entbuf, sizeof(entbuf), i, "rdnss");
819 		addr = (char *)agetstr(entbuf, &bp);
820 		if (addr == NULL)
821 			continue;
822 		ELM_MALLOC(rdn, exit(1));
823 
824 		TAILQ_INIT(&rdn->rd_list);
825 
826 		for (ap = addr; ap - addr < (ssize_t)strlen(addr); ap += c+1) {
827 			c = strcspn(ap, ",");
828 			strncpy(abuf, ap, c);
829 			abuf[c] = '\0';
830 			ELM_MALLOC(rdna, goto getconfig_free_rdn);
831 			if (inet_pton(AF_INET6, abuf, &rdna->ra_dns) != 1) {
832 				syslog(LOG_ERR, "<%s> inet_pton failed for %s",
833 				    __func__, abuf);
834 				free(rdna);
835 				goto getconfig_free_rdn;
836 			}
837 			TAILQ_INSERT_TAIL(&rdn->rd_list, rdna, ra_next);
838 		}
839 
840 		makeentry(entbuf, sizeof(entbuf), i, "rdnssltime");
841 		MAYHAVE(val, entbuf, (rai->rai_maxinterval * 3 / 2));
842 		if ((uint16_t)val < rai->rai_maxinterval ||
843 		    (uint16_t)val > rai->rai_maxinterval * 2) {
844 			syslog(LOG_ERR, "%s (%" PRIu16 ") on %s is invalid "
845 			    "(must be between %d and %d)",
846 			    entbuf, val, ifi->ifi_ifname, rai->rai_maxinterval,
847 			    rai->rai_maxinterval * 2);
848 			goto getconfig_free_rdn;
849 		}
850 		rdn->rd_ltime = val;
851 
852 		/* link into chain */
853 		TAILQ_INSERT_TAIL(&rai->rai_rdnss, rdn, rd_next);
854 		continue;
855 getconfig_free_rdn:
856 		while ((rdna = TAILQ_FIRST(&rdn->rd_list)) != NULL) {
857 			TAILQ_REMOVE(&rdn->rd_list, rdna, ra_next);
858 			free(rdna);
859 		}
860 		free(rdn);
861 	}
862 
863 	for (i = -1; i < MAXDNSSLENT ; i++) {
864 		struct dnssl *dns;
865 		struct dnssl_addr *dnsa;
866 		char *ap;
867 		int c;
868 
869 		makeentry(entbuf, sizeof(entbuf), i, "dnssl");
870 		addr = (char *)agetstr(entbuf, &bp);
871 		if (addr == NULL)
872 			continue;
873 
874 		ELM_MALLOC(dns, exit(1));
875 
876 		TAILQ_INIT(&dns->dn_list);
877 
878 		for (ap = addr; ap - addr < (ssize_t)strlen(addr); ap += c+1) {
879 			c = strcspn(ap, ",");
880 			strncpy(abuf, ap, c);
881 			abuf[c] = '\0';
882 			ELM_MALLOC(dnsa, goto getconfig_free_dns);
883 			dnsa->da_len = dname_labelenc(dnsa->da_dom, abuf);
884 			if (dnsa->da_len < 0) {
885 				syslog(LOG_ERR, "Invalid dnssl entry: %s",
886 				    abuf);
887 				goto getconfig_free_dns;
888 			}
889 			syslog(LOG_DEBUG, "<%s>: dnsa->da_len = %d", __func__,
890 			    dnsa->da_len);
891 			TAILQ_INSERT_TAIL(&dns->dn_list, dnsa, da_next);
892 		}
893 
894 		makeentry(entbuf, sizeof(entbuf), i, "dnsslltime");
895 		MAYHAVE(val, entbuf, (rai->rai_maxinterval * 3 / 2));
896 		if ((uint16_t)val < rai->rai_maxinterval ||
897 		    (uint16_t)val > rai->rai_maxinterval * 2) {
898 			syslog(LOG_ERR, "%s (%" PRIu16 ") on %s is invalid "
899 			    "(must be between %d and %d)",
900 			    entbuf, val, ifi->ifi_ifname, rai->rai_maxinterval,
901 			    rai->rai_maxinterval * 2);
902 			goto getconfig_free_dns;
903 		}
904 		dns->dn_ltime = val;
905 
906 		/* link into chain */
907 		TAILQ_INSERT_TAIL(&rai->rai_dnssl, dns, dn_next);
908 		continue;
909 getconfig_free_dns:
910 		while ((dnsa = TAILQ_FIRST(&dns->dn_list)) != NULL) {
911 			TAILQ_REMOVE(&dns->dn_list, dnsa, da_next);
912 			free(dnsa);
913 		}
914 		free(dns);
915 	}
916 	/* construct the sending packet */
917 	make_packet(rai);
918 
919 	/*
920 	 * If an entry with the same ifindex exists, remove it first.
921 	 * Before the removal, RDNSS and DNSSL options with
922 	 * zero-lifetime will be sent.
923 	 */
924 	switch (ifi->ifi_state) {
925 	case IFI_STATE_UNCONFIGURED:
926 		/* UNCONFIGURED -> TRANSITIVE */
927 
928 		error = sock_mc_join(&sock, ifi->ifi_ifindex);
929 		if (error)
930 			exit(1);
931 
932 		ifi->ifi_state = IFI_STATE_TRANSITIVE;
933 		ifi->ifi_burstcount = MAX_INITIAL_RTR_ADVERTISEMENTS;
934 		ifi->ifi_burstinterval = MAX_INITIAL_RTR_ADVERT_INTERVAL;
935 
936 		/* The same two rai mean initial burst */
937 		ifi->ifi_rainfo = rai;
938 		ifi->ifi_rainfo_trans = rai;
939 		TAILQ_INSERT_TAIL(&railist, rai, rai_next);
940 
941 		if (ifi->ifi_ra_timer == NULL)
942 			ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout,
943 			    ra_timer_update, ifi, ifi);
944 		ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
945 		rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
946 		    ifi->ifi_ra_timer);
947 
948 		syslog(LOG_DEBUG,
949 		    "<%s> ifname=%s marked as TRANSITIVE (initial burst).",
950 		    __func__, ifi->ifi_ifname);
951 		break;
952 	case IFI_STATE_CONFIGURED:
953 		/* CONFIGURED -> TRANSITIVE */
954 		rai_old = ifi->ifi_rainfo;
955 		if (rai_old == NULL) {
956 			syslog(LOG_ERR,
957 			    "<%s> ifi_rainfo is NULL"
958 			    " in IFI_STATE_CONFIGURED.", __func__);
959 			ifi = NULL;
960 			break;
961 		} else {
962 			struct rdnss *rdn;
963 			struct dnssl *dns;
964 
965 			rai_old->rai_lifetime = 0;
966 			TAILQ_FOREACH(rdn, &rai_old->rai_rdnss, rd_next)
967 			    rdn->rd_ltime = 0;
968 			TAILQ_FOREACH(dns, &rai_old->rai_dnssl, dn_next)
969 			    dns->dn_ltime = 0;
970 
971 			ifi->ifi_rainfo_trans = rai_old;
972 			ifi->ifi_state = IFI_STATE_TRANSITIVE;
973 			ifi->ifi_burstcount = MAX_FINAL_RTR_ADVERTISEMENTS;
974 			ifi->ifi_burstinterval = MIN_DELAY_BETWEEN_RAS;
975 
976 			ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
977 			rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
978 			    ifi->ifi_ra_timer);
979 
980 			syslog(LOG_DEBUG,
981 			    "<%s> ifname=%s marked as TRANSITIVE"
982 			    " (transitional burst)",
983 			    __func__, ifi->ifi_ifname);
984 		}
985 		ifi->ifi_rainfo = rai;
986 		TAILQ_INSERT_TAIL(&railist, rai, rai_next);
987 		break;
988 	case IFI_STATE_TRANSITIVE:
989 		if (ifi->ifi_rainfo != NULL) {
990 			if (ifi->ifi_rainfo == ifi->ifi_rainfo_trans) {
991 				/* Reinitialize initial burst */
992 				rm_rainfo(ifi->ifi_rainfo);
993 				ifi->ifi_rainfo = rai;
994 				ifi->ifi_rainfo_trans = rai;
995 				ifi->ifi_burstcount =
996 				    MAX_INITIAL_RTR_ADVERTISEMENTS;
997 				ifi->ifi_burstinterval =
998 				    MAX_INITIAL_RTR_ADVERT_INTERVAL;
999 			} else {
1000 				/* Replace ifi_rainfo with the new one */
1001 				rm_rainfo(ifi->ifi_rainfo);
1002 				ifi->ifi_rainfo = rai;
1003 			}
1004 			TAILQ_INSERT_TAIL(&railist, rai, rai_next);
1005 
1006 			ra_timer_update(ifi, &ifi->ifi_ra_timer->rat_tm);
1007 			rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
1008 			    ifi->ifi_ra_timer);
1009 		} else {
1010 			/* XXX: NOTREACHED.  Being shut down. */
1011 			syslog(LOG_ERR,
1012 			    "<%s> %s is shutting down.  Skipped.",
1013 			    __func__, ifi->ifi_ifname);
1014 			rm_rainfo(rai);
1015 
1016 			return (NULL);
1017 		}
1018 		break;
1019 	}
1020 
1021 	return (ifi);
1022 
1023 getconfig_free_rai:
1024 	free(rai);
1025 	return (NULL);
1026 }
1027 
1028 void
1029 get_prefix(struct rainfo *rai)
1030 {
1031 	struct ifaddrs *ifap, *ifa;
1032 	struct prefix *pfx;
1033 	struct in6_addr *a;
1034 	struct ifinfo *ifi;
1035 	char *p, *ep, *m, *lim;
1036 	char ntopbuf[INET6_ADDRSTRLEN];
1037 
1038 	if (getifaddrs(&ifap) < 0) {
1039 		syslog(LOG_ERR,
1040 		    "<%s> can't get interface addresses",
1041 		    __func__);
1042 		exit(1);
1043 	}
1044 	ifi = rai->rai_ifinfo;
1045 
1046 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
1047 		int plen;
1048 
1049 		if (strcmp(ifa->ifa_name, ifi->ifi_ifname) != 0)
1050 			continue;
1051 		if (ifa->ifa_addr->sa_family != AF_INET6)
1052 			continue;
1053 		a = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
1054 		if (IN6_IS_ADDR_LINKLOCAL(a))
1055 			continue;
1056 
1057 		/* get prefix length */
1058 		m = (char *)&((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr;
1059 		lim = (char *)(ifa->ifa_netmask) + ifa->ifa_netmask->sa_len;
1060 		plen = prefixlen(m, lim);
1061 		if (plen <= 0 || plen > 128) {
1062 			syslog(LOG_ERR, "<%s> failed to get prefixlen "
1063 			    "or prefix is invalid",
1064 			    __func__);
1065 			exit(1);
1066 		}
1067 		if (plen == 128)	/* XXX */
1068 			continue;
1069 		if (find_prefix(rai, a, plen)) {
1070 			/* ignore a duplicated prefix. */
1071 			continue;
1072 		}
1073 
1074 		/* allocate memory to store prefix info. */
1075 		ELM_MALLOC(pfx, exit(1));
1076 
1077 		/* set prefix, sweep bits outside of prefixlen */
1078 		pfx->pfx_prefixlen = plen;
1079 		memcpy(&pfx->pfx_prefix, a, sizeof(*a));
1080 		p = (char *)&pfx->pfx_prefix;
1081 		ep = (char *)(&pfx->pfx_prefix + 1);
1082 		while (m < lim && p < ep)
1083 			*p++ &= *m++;
1084 		while (p < ep)
1085 			*p++ = 0x00;
1086 	        if (!inet_ntop(AF_INET6, &pfx->pfx_prefix, ntopbuf,
1087 	            sizeof(ntopbuf))) {
1088 			syslog(LOG_ERR, "<%s> inet_ntop failed", __func__);
1089 			exit(1);
1090 		}
1091 		syslog(LOG_DEBUG,
1092 		    "<%s> add %s/%d to prefix list on %s",
1093 		    __func__, ntopbuf, pfx->pfx_prefixlen, ifi->ifi_ifname);
1094 
1095 		/* set other fields with protocol defaults */
1096 		pfx->pfx_validlifetime = DEF_ADVVALIDLIFETIME;
1097 		pfx->pfx_preflifetime = DEF_ADVPREFERREDLIFETIME;
1098 		pfx->pfx_onlinkflg = 1;
1099 		pfx->pfx_autoconfflg = 1;
1100 		pfx->pfx_origin = PREFIX_FROM_KERNEL;
1101 		pfx->pfx_rainfo = rai;
1102 
1103 		/* link into chain */
1104 		TAILQ_INSERT_TAIL(&rai->rai_prefix, pfx, pfx_next);
1105 
1106 		/* counter increment */
1107 		rai->rai_pfxs++;
1108 	}
1109 
1110 	freeifaddrs(ifap);
1111 }
1112 
1113 static void
1114 makeentry(char *buf, size_t len, int id, const char *string)
1115 {
1116 
1117 	if (id < 0)
1118 		strlcpy(buf, string, len);
1119 	else
1120 		snprintf(buf, len, "%s%d", string, id);
1121 }
1122 
1123 /*
1124  * Add a prefix to the list of specified interface and reconstruct
1125  * the outgoing packet.
1126  * The prefix must not be in the list.
1127  * XXX: other parameters of the prefix (e.g. lifetime) should be
1128  * able to be specified.
1129  */
1130 static void
1131 add_prefix(struct rainfo *rai, struct in6_prefixreq *ipr)
1132 {
1133 	struct prefix *pfx;
1134 	struct ifinfo *ifi;
1135 	char ntopbuf[INET6_ADDRSTRLEN];
1136 
1137 	ifi = rai->rai_ifinfo;
1138 	ELM_MALLOC(pfx, return);
1139 	pfx->pfx_prefix = ipr->ipr_prefix.sin6_addr;
1140 	pfx->pfx_prefixlen = ipr->ipr_plen;
1141 	pfx->pfx_validlifetime = ipr->ipr_vltime;
1142 	pfx->pfx_preflifetime = ipr->ipr_pltime;
1143 	pfx->pfx_onlinkflg = ipr->ipr_raf_onlink;
1144 	pfx->pfx_autoconfflg = ipr->ipr_raf_auto;
1145 	pfx->pfx_origin = PREFIX_FROM_DYNAMIC;
1146 	pfx->pfx_rainfo = rai;
1147 
1148 	TAILQ_INSERT_TAIL(&rai->rai_prefix, pfx, pfx_next);
1149 
1150 	syslog(LOG_DEBUG, "<%s> new prefix %s/%d was added on %s",
1151 	    __func__,
1152 	    inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf,
1153 		sizeof(ntopbuf)), ipr->ipr_plen, ifi->ifi_ifname);
1154 
1155 	rai->rai_pfxs++;
1156 }
1157 
1158 /*
1159  * Delete a prefix to the list of specified interface and reconstruct
1160  * the outgoing packet.
1161  * The prefix must be in the list.
1162  */
1163 void
1164 delete_prefix(struct prefix *pfx)
1165 {
1166 	struct rainfo *rai;
1167 	struct ifinfo *ifi;
1168 	char ntopbuf[INET6_ADDRSTRLEN];
1169 
1170 	rai = pfx->pfx_rainfo;
1171 	ifi = rai->rai_ifinfo;
1172 	TAILQ_REMOVE(&rai->rai_prefix, pfx, pfx_next);
1173 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was deleted on %s",
1174 	    __func__,
1175 	    inet_ntop(AF_INET6, &pfx->pfx_prefix, ntopbuf,
1176 		sizeof(ntopbuf)), pfx->pfx_prefixlen, ifi->ifi_ifname);
1177 	if (pfx->pfx_timer)
1178 		rtadvd_remove_timer(pfx->pfx_timer);
1179 	free(pfx);
1180 
1181 	rai->rai_pfxs--;
1182 }
1183 
1184 void
1185 invalidate_prefix(struct prefix *pfx)
1186 {
1187 	struct timespec timo;
1188 	struct rainfo *rai;
1189 	struct ifinfo *ifi;
1190 	char ntopbuf[INET6_ADDRSTRLEN];
1191 
1192 	rai = pfx->pfx_rainfo;
1193 	ifi = rai->rai_ifinfo;
1194 	if (pfx->pfx_timer) {	/* sanity check */
1195 		syslog(LOG_ERR,
1196 		    "<%s> assumption failure: timer already exists",
1197 		    __func__);
1198 		exit(1);
1199 	}
1200 
1201 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was invalidated on %s, "
1202 	    "will expire in %ld seconds", __func__,
1203 	    inet_ntop(AF_INET6, &pfx->pfx_prefix, ntopbuf, sizeof(ntopbuf)),
1204 	    pfx->pfx_prefixlen, ifi->ifi_ifname, (long)prefix_timo);
1205 
1206 	/* set the expiration timer */
1207 	pfx->pfx_timer = rtadvd_add_timer(prefix_timeout, NULL, pfx, NULL);
1208 	if (pfx->pfx_timer == NULL) {
1209 		syslog(LOG_ERR, "<%s> failed to add a timer for a prefix. "
1210 		    "remove the prefix", __func__);
1211 		delete_prefix(pfx);
1212 	}
1213 	timo.tv_sec = prefix_timo;
1214 	timo.tv_nsec = 0;
1215 	rtadvd_set_timer(&timo, pfx->pfx_timer);
1216 }
1217 
1218 static struct rtadvd_timer *
1219 prefix_timeout(void *arg)
1220 {
1221 
1222 	delete_prefix((struct prefix *)arg);
1223 
1224 	return (NULL);
1225 }
1226 
1227 void
1228 update_prefix(struct prefix *pfx)
1229 {
1230 	struct rainfo *rai;
1231 	struct ifinfo *ifi;
1232 	char ntopbuf[INET6_ADDRSTRLEN];
1233 
1234 	rai = pfx->pfx_rainfo;
1235 	ifi = rai->rai_ifinfo;
1236 	if (pfx->pfx_timer == NULL) { /* sanity check */
1237 		syslog(LOG_ERR,
1238 		    "<%s> assumption failure: timer does not exist",
1239 		    __func__);
1240 		exit(1);
1241 	}
1242 
1243 	syslog(LOG_DEBUG, "<%s> prefix %s/%d was re-enabled on %s",
1244 	    __func__, inet_ntop(AF_INET6, &pfx->pfx_prefix, ntopbuf,
1245 		sizeof(ntopbuf)), pfx->pfx_prefixlen, ifi->ifi_ifname);
1246 
1247 	/* stop the expiration timer */
1248 	rtadvd_remove_timer(pfx->pfx_timer);
1249 	pfx->pfx_timer = NULL;
1250 }
1251 
1252 /*
1253  * Try to get an in6_prefixreq contents for a prefix which matches
1254  * ipr->ipr_prefix and ipr->ipr_plen and belongs to
1255  * the interface whose name is ipr->ipr_name[].
1256  */
1257 static int
1258 init_prefix(struct in6_prefixreq *ipr)
1259 {
1260 #if 0
1261 	int s;
1262 
1263 	if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
1264 		syslog(LOG_ERR, "<%s> socket: %s", __func__,
1265 		    strerror(errno));
1266 		exit(1);
1267 	}
1268 
1269 	if (ioctl(s, SIOCGIFPREFIX_IN6, (caddr_t)ipr) < 0) {
1270 		syslog(LOG_INFO, "<%s> ioctl:SIOCGIFPREFIX %s", __func__,
1271 		    strerror(errno));
1272 
1273 		ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
1274 		ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
1275 		ipr->ipr_raf_onlink = 1;
1276 		ipr->ipr_raf_auto = 1;
1277 		/* omit other field initialization */
1278 	}
1279 	else if (ipr->ipr_origin < PR_ORIG_RR) {
1280 		char ntopbuf[INET6_ADDRSTRLEN];
1281 
1282 		syslog(LOG_WARNING, "<%s> Added prefix(%s)'s origin %d is"
1283 		    "lower than PR_ORIG_RR(router renumbering)."
1284 		    "This should not happen if I am router", __func__,
1285 		    inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf,
1286 			sizeof(ntopbuf)), ipr->ipr_origin);
1287 		close(s);
1288 		return (1);
1289 	}
1290 
1291 	close(s);
1292 	return (0);
1293 #else
1294 	ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
1295 	ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
1296 	ipr->ipr_raf_onlink = 1;
1297 	ipr->ipr_raf_auto = 1;
1298 	return (0);
1299 #endif
1300 }
1301 
1302 void
1303 make_prefix(struct rainfo *rai, int ifindex, struct in6_addr *addr, int plen)
1304 {
1305 	struct in6_prefixreq ipr;
1306 
1307 	memset(&ipr, 0, sizeof(ipr));
1308 	if (if_indextoname(ifindex, ipr.ipr_name) == NULL) {
1309 		syslog(LOG_ERR, "<%s> Prefix added interface No.%d doesn't "
1310 		    "exist. This should not happen! %s", __func__,
1311 		    ifindex, strerror(errno));
1312 		exit(1);
1313 	}
1314 	ipr.ipr_prefix.sin6_len = sizeof(ipr.ipr_prefix);
1315 	ipr.ipr_prefix.sin6_family = AF_INET6;
1316 	ipr.ipr_prefix.sin6_addr = *addr;
1317 	ipr.ipr_plen = plen;
1318 
1319 	if (init_prefix(&ipr))
1320 		return; /* init failed by some error */
1321 	add_prefix(rai, &ipr);
1322 }
1323 
1324 void
1325 make_packet(struct rainfo *rai)
1326 {
1327 	size_t packlen, lladdroptlen = 0;
1328 	char *buf;
1329 	struct nd_router_advert *ra;
1330 	struct nd_opt_prefix_info *ndopt_pi;
1331 	struct nd_opt_mtu *ndopt_mtu;
1332 	struct nd_opt_route_info *ndopt_rti;
1333 	struct rtinfo *rti;
1334 	struct nd_opt_rdnss *ndopt_rdnss;
1335 	struct rdnss *rdn;
1336 	struct nd_opt_dnssl *ndopt_dnssl;
1337 	struct dnssl *dns;
1338 	size_t len;
1339 	struct prefix *pfx;
1340 	struct ifinfo *ifi;
1341 
1342 	ifi = rai->rai_ifinfo;
1343 	/* calculate total length */
1344 	packlen = sizeof(struct nd_router_advert);
1345 	if (rai->rai_advlinkopt) {
1346 		if ((lladdroptlen = lladdropt_length(&ifi->ifi_sdl)) == 0) {
1347 			syslog(LOG_INFO,
1348 			    "<%s> link-layer address option has"
1349 			    " null length on %s.  Treat as not included.",
1350 			    __func__, ifi->ifi_ifname);
1351 			rai->rai_advlinkopt = 0;
1352 		}
1353 		packlen += lladdroptlen;
1354 	}
1355 	if (rai->rai_pfxs)
1356 		packlen += sizeof(struct nd_opt_prefix_info) * rai->rai_pfxs;
1357 	if (rai->rai_linkmtu)
1358 		packlen += sizeof(struct nd_opt_mtu);
1359 
1360 	TAILQ_FOREACH(rti, &rai->rai_route, rti_next)
1361 		packlen += sizeof(struct nd_opt_route_info) +
1362 			   ((rti->rti_prefixlen + 0x3f) >> 6) * 8;
1363 
1364 	TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next) {
1365 		struct rdnss_addr *rdna;
1366 
1367 		packlen += sizeof(struct nd_opt_rdnss);
1368 		TAILQ_FOREACH(rdna, &rdn->rd_list, ra_next)
1369 			packlen += sizeof(rdna->ra_dns);
1370 	}
1371 	TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next) {
1372 		struct dnssl_addr *dnsa;
1373 
1374 		packlen += sizeof(struct nd_opt_dnssl);
1375 		len = 0;
1376 		TAILQ_FOREACH(dnsa, &dns->dn_list, da_next)
1377 			len += dnsa->da_len;
1378 
1379 		/* A zero octet and 8 octet boundary */
1380 		len++;
1381 		len += (len % 8) ? 8 - len % 8 : 0;
1382 
1383 		packlen += len;
1384 	}
1385 	/* allocate memory for the packet */
1386 	if ((buf = malloc(packlen)) == NULL) {
1387 		syslog(LOG_ERR,
1388 		    "<%s> can't get enough memory for an RA packet",
1389 		    __func__);
1390 		exit(1);
1391 	}
1392 	memset(buf, 0, packlen);
1393 	if (rai->rai_ra_data)	/* Free old data if any. */
1394 		free(rai->rai_ra_data);
1395 	rai->rai_ra_data = buf;
1396 	/* XXX: what if packlen > 576? */
1397 	rai->rai_ra_datalen = packlen;
1398 
1399 	/*
1400 	 * construct the packet
1401 	 */
1402 	ra = (struct nd_router_advert *)buf;
1403 	ra->nd_ra_type = ND_ROUTER_ADVERT;
1404 	ra->nd_ra_code = 0;
1405 	ra->nd_ra_cksum = 0;
1406 	ra->nd_ra_curhoplimit = (uint8_t)(0xff & rai->rai_hoplimit);
1407 	/*
1408 	 * XXX: the router preference field, which is a 2-bit field, should be
1409 	 * initialized before other fields.
1410 	 */
1411 	ra->nd_ra_flags_reserved = 0xff & rai->rai_rtpref;
1412 	ra->nd_ra_flags_reserved |=
1413 		rai->rai_managedflg ? ND_RA_FLAG_MANAGED : 0;
1414 	ra->nd_ra_flags_reserved |=
1415 		rai->rai_otherflg ? ND_RA_FLAG_OTHER : 0;
1416 #ifdef DRAFT_IETF_6MAN_IPV6ONLY_FLAG
1417 	ra->nd_ra_flags_reserved |=
1418 		rai->rai_ipv6onlyflg ? ND_RA_FLAG_IPV6_ONLY : 0;
1419 #endif
1420 	ra->nd_ra_router_lifetime = htons(rai->rai_lifetime);
1421 	ra->nd_ra_reachable = htonl(rai->rai_reachabletime);
1422 	ra->nd_ra_retransmit = htonl(rai->rai_retranstimer);
1423 	buf += sizeof(*ra);
1424 
1425 	if (rai->rai_advlinkopt) {
1426 		lladdropt_fill(&ifi->ifi_sdl, (struct nd_opt_hdr *)buf);
1427 		buf += lladdroptlen;
1428 	}
1429 
1430 	if (rai->rai_linkmtu) {
1431 		ndopt_mtu = (struct nd_opt_mtu *)buf;
1432 		ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU;
1433 		ndopt_mtu->nd_opt_mtu_len = 1;
1434 		ndopt_mtu->nd_opt_mtu_reserved = 0;
1435 		ndopt_mtu->nd_opt_mtu_mtu = htonl(rai->rai_linkmtu);
1436 		buf += sizeof(struct nd_opt_mtu);
1437 	}
1438 
1439 	TAILQ_FOREACH(pfx, &rai->rai_prefix, pfx_next) {
1440 		uint32_t vltime, pltime;
1441 		struct timespec now;
1442 
1443 		ndopt_pi = (struct nd_opt_prefix_info *)buf;
1444 		ndopt_pi->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
1445 		ndopt_pi->nd_opt_pi_len = 4;
1446 		ndopt_pi->nd_opt_pi_prefix_len = pfx->pfx_prefixlen;
1447 		ndopt_pi->nd_opt_pi_flags_reserved = 0;
1448 		if (pfx->pfx_onlinkflg)
1449 			ndopt_pi->nd_opt_pi_flags_reserved |=
1450 				ND_OPT_PI_FLAG_ONLINK;
1451 		if (pfx->pfx_autoconfflg)
1452 			ndopt_pi->nd_opt_pi_flags_reserved |=
1453 				ND_OPT_PI_FLAG_AUTO;
1454 		if (pfx->pfx_timer)
1455 			vltime = 0;
1456 		else {
1457 			if (pfx->pfx_vltimeexpire || pfx->pfx_pltimeexpire)
1458 				clock_gettime(CLOCK_MONOTONIC_FAST, &now);
1459 			if (pfx->pfx_vltimeexpire == 0)
1460 				vltime = pfx->pfx_validlifetime;
1461 			else
1462 				vltime = ((time_t)pfx->pfx_vltimeexpire > now.tv_sec) ?
1463 				    pfx->pfx_vltimeexpire - now.tv_sec : 0;
1464 		}
1465 		if (pfx->pfx_timer)
1466 			pltime = 0;
1467 		else {
1468 			if (pfx->pfx_pltimeexpire == 0)
1469 				pltime = pfx->pfx_preflifetime;
1470 			else
1471 				pltime = ((time_t)pfx->pfx_pltimeexpire > now.tv_sec) ?
1472 				    pfx->pfx_pltimeexpire - now.tv_sec : 0;
1473 		}
1474 		if (vltime < pltime) {
1475 			/*
1476 			 * this can happen if vltime is decrement but pltime
1477 			 * is not.
1478 			 */
1479 			pltime = vltime;
1480 		}
1481 		ndopt_pi->nd_opt_pi_valid_time = htonl(vltime);
1482 		ndopt_pi->nd_opt_pi_preferred_time = htonl(pltime);
1483 		ndopt_pi->nd_opt_pi_reserved2 = 0;
1484 		ndopt_pi->nd_opt_pi_prefix = pfx->pfx_prefix;
1485 
1486 		buf += sizeof(struct nd_opt_prefix_info);
1487 	}
1488 
1489 	TAILQ_FOREACH(rti, &rai->rai_route, rti_next) {
1490 		uint8_t psize = (rti->rti_prefixlen + 0x3f) >> 6;
1491 
1492 		ndopt_rti = (struct nd_opt_route_info *)buf;
1493 		ndopt_rti->nd_opt_rti_type = ND_OPT_ROUTE_INFO;
1494 		ndopt_rti->nd_opt_rti_len = 1 + psize;
1495 		ndopt_rti->nd_opt_rti_prefixlen = rti->rti_prefixlen;
1496 		ndopt_rti->nd_opt_rti_flags = 0xff & rti->rti_rtpref;
1497 		ndopt_rti->nd_opt_rti_lifetime = htonl(rti->rti_ltime);
1498 		memcpy(ndopt_rti + 1, &rti->rti_prefix, psize * 8);
1499 		buf += sizeof(struct nd_opt_route_info) + psize * 8;
1500 	}
1501 
1502 	TAILQ_FOREACH(rdn, &rai->rai_rdnss, rd_next) {
1503 		struct rdnss_addr *rdna;
1504 
1505 		ndopt_rdnss = (struct nd_opt_rdnss *)buf;
1506 		ndopt_rdnss->nd_opt_rdnss_type = ND_OPT_RDNSS;
1507 		ndopt_rdnss->nd_opt_rdnss_len = 0;
1508 		ndopt_rdnss->nd_opt_rdnss_reserved = 0;
1509 		ndopt_rdnss->nd_opt_rdnss_lifetime = htonl(rdn->rd_ltime);
1510 		buf += sizeof(struct nd_opt_rdnss);
1511 
1512 		TAILQ_FOREACH(rdna, &rdn->rd_list, ra_next) {
1513 			memcpy(buf, &rdna->ra_dns, sizeof(rdna->ra_dns));
1514 			buf += sizeof(rdna->ra_dns);
1515 		}
1516 		/* Length field should be in 8 octets */
1517 		ndopt_rdnss->nd_opt_rdnss_len = (buf - (char *)ndopt_rdnss) / 8;
1518 
1519 		syslog(LOG_DEBUG, "<%s>: nd_opt_dnss_len = %d", __func__,
1520 		    ndopt_rdnss->nd_opt_rdnss_len);
1521 	}
1522 
1523 	TAILQ_FOREACH(dns, &rai->rai_dnssl, dn_next) {
1524 		struct dnssl_addr *dnsa;
1525 
1526 		ndopt_dnssl = (struct nd_opt_dnssl *)buf;
1527 		ndopt_dnssl->nd_opt_dnssl_type = ND_OPT_DNSSL;
1528 		ndopt_dnssl->nd_opt_dnssl_len = 0;
1529 		ndopt_dnssl->nd_opt_dnssl_reserved = 0;
1530 		ndopt_dnssl->nd_opt_dnssl_lifetime = htonl(dns->dn_ltime);
1531 		buf += sizeof(*ndopt_dnssl);
1532 
1533 		TAILQ_FOREACH(dnsa, &dns->dn_list, da_next) {
1534 			memcpy(buf, dnsa->da_dom, dnsa->da_len);
1535 			buf += dnsa->da_len;
1536 		}
1537 
1538 		/* A zero octet after encoded DNS server list. */
1539 		*buf++ = '\0';
1540 
1541 		/* Padding to next 8 octets boundary */
1542 		len = buf - (char *)ndopt_dnssl;
1543 		len += (len % 8) ? 8 - len % 8 : 0;
1544 		buf = (char *)ndopt_dnssl + len;
1545 
1546 		/* Length field must be in 8 octets */
1547 		ndopt_dnssl->nd_opt_dnssl_len = len / 8;
1548 
1549 		syslog(LOG_DEBUG, "<%s>: nd_opt_dnssl_len = %d", __func__,
1550 		    ndopt_dnssl->nd_opt_dnssl_len);
1551 	}
1552 	return;
1553 }
1554