xref: /netbsd-src/sys/netinet6/in6.c (revision 9ddb6ab554e70fb9bbd90c3d96b812bc57755a14)
1 /*	$NetBSD: in6.c,v 1.159 2011/11/19 22:51:26 tls Exp $	*/
2 /*	$KAME: in6.c,v 1.198 2001/07/18 09:12:38 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 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 /*
34  * Copyright (c) 1982, 1986, 1991, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  *
61  *	@(#)in.c	8.2 (Berkeley) 11/15/93
62  */
63 
64 #include <sys/cdefs.h>
65 __KERNEL_RCSID(0, "$NetBSD: in6.c,v 1.159 2011/11/19 22:51:26 tls Exp $");
66 
67 #include "opt_inet.h"
68 #include "opt_pfil_hooks.h"
69 #include "opt_compat_netbsd.h"
70 
71 #include <sys/param.h>
72 #include <sys/ioctl.h>
73 #include <sys/errno.h>
74 #include <sys/malloc.h>
75 #include <sys/socket.h>
76 #include <sys/socketvar.h>
77 #include <sys/sockio.h>
78 #include <sys/systm.h>
79 #include <sys/proc.h>
80 #include <sys/time.h>
81 #include <sys/kernel.h>
82 #include <sys/syslog.h>
83 #include <sys/kauth.h>
84 #include <sys/cprng.h>
85 
86 #include <net/if.h>
87 #include <net/if_types.h>
88 #include <net/route.h>
89 #include <net/if_dl.h>
90 
91 #include <netinet/in.h>
92 #include <netinet/in_var.h>
93 #include <net/if_ether.h>
94 
95 #include <netinet/ip6.h>
96 #include <netinet6/ip6_var.h>
97 #include <netinet6/nd6.h>
98 #include <netinet6/mld6_var.h>
99 #include <netinet6/ip6_mroute.h>
100 #include <netinet6/in6_ifattach.h>
101 #include <netinet6/scope6_var.h>
102 
103 #include <net/net_osdep.h>
104 
105 #ifdef PFIL_HOOKS
106 #include <net/pfil.h>
107 #endif
108 #ifdef COMPAT_50
109 #include <compat/netinet6/in6_var.h>
110 #endif
111 
112 MALLOC_DEFINE(M_IP6OPT, "ip6_options", "IPv6 options");
113 
114 /* enable backward compatibility code for obsoleted ioctls */
115 #define COMPAT_IN6IFIOCTL
116 
117 #ifdef	IN6_DEBUG
118 #define	IN6_DPRINTF(__fmt, ...)	printf(__fmt, __VA_ARGS__)
119 #else
120 #define	IN6_DPRINTF(__fmt, ...)	do { } while (/*CONSTCOND*/0)
121 #endif /* IN6_DEBUG */
122 
123 /*
124  * Definitions of some constant IP6 addresses.
125  */
126 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
127 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
128 const struct in6_addr in6addr_nodelocal_allnodes =
129 	IN6ADDR_NODELOCAL_ALLNODES_INIT;
130 const struct in6_addr in6addr_linklocal_allnodes =
131 	IN6ADDR_LINKLOCAL_ALLNODES_INIT;
132 const struct in6_addr in6addr_linklocal_allrouters =
133 	IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
134 
135 const struct in6_addr in6mask0 = IN6MASK0;
136 const struct in6_addr in6mask32 = IN6MASK32;
137 const struct in6_addr in6mask64 = IN6MASK64;
138 const struct in6_addr in6mask96 = IN6MASK96;
139 const struct in6_addr in6mask128 = IN6MASK128;
140 
141 const struct sockaddr_in6 sa6_any = {sizeof(sa6_any), AF_INET6,
142 				     0, 0, IN6ADDR_ANY_INIT, 0};
143 
144 static int in6_lifaddr_ioctl(struct socket *, u_long, void *,
145 	struct ifnet *, struct lwp *);
146 static int in6_ifinit(struct ifnet *, struct in6_ifaddr *,
147 	const struct sockaddr_in6 *, int);
148 static void in6_unlink_ifa(struct in6_ifaddr *, struct ifnet *);
149 
150 /*
151  * Subroutine for in6_ifaddloop() and in6_ifremloop().
152  * This routine does actual work.
153  */
154 static void
155 in6_ifloop_request(int cmd, struct ifaddr *ifa)
156 {
157 	struct sockaddr_in6 lo_sa;
158 	struct sockaddr_in6 all1_sa;
159 	struct rtentry *nrt = NULL;
160 	int e;
161 
162 	sockaddr_in6_init(&all1_sa, &in6mask128, 0, 0, 0);
163 	sockaddr_in6_init(&lo_sa, &in6addr_loopback, 0, 0, 0);
164 
165 	/*
166 	 * We specify the address itself as the gateway, and set the
167 	 * RTF_LLINFO flag, so that the corresponding host route would have
168 	 * the flag, and thus applications that assume traditional behavior
169 	 * would be happy.  Note that we assume the caller of the function
170 	 * (probably implicitly) set nd6_rtrequest() to ifa->ifa_rtrequest,
171 	 * which changes the outgoing interface to the loopback interface.
172 	 */
173 	e = rtrequest(cmd, ifa->ifa_addr, ifa->ifa_addr,
174 	    (struct sockaddr *)&all1_sa, RTF_UP|RTF_HOST|RTF_LLINFO, &nrt);
175 	if (e != 0) {
176 		log(LOG_ERR, "in6_ifloop_request: "
177 		    "%s operation failed for %s (errno=%d)\n",
178 		    cmd == RTM_ADD ? "ADD" : "DELETE",
179 		    ip6_sprintf(&((struct in6_ifaddr *)ifa)->ia_addr.sin6_addr),
180 		    e);
181 	}
182 
183 	/*
184 	 * Make sure rt_ifa be equal to IFA, the second argument of the
185 	 * function.
186 	 * We need this because when we refer to rt_ifa->ia6_flags in
187 	 * ip6_input, we assume that the rt_ifa points to the address instead
188 	 * of the loopback address.
189 	 */
190 	if (cmd == RTM_ADD && nrt && ifa != nrt->rt_ifa)
191 		rt_replace_ifa(nrt, ifa);
192 
193 	/*
194 	 * Report the addition/removal of the address to the routing socket.
195 	 * XXX: since we called rtinit for a p2p interface with a destination,
196 	 *      we end up reporting twice in such a case.  Should we rather
197 	 *      omit the second report?
198 	 */
199 	if (nrt) {
200 		rt_newaddrmsg(cmd, ifa, e, nrt);
201 		if (cmd == RTM_DELETE) {
202 			if (nrt->rt_refcnt <= 0) {
203 				/* XXX: we should free the entry ourselves. */
204 				nrt->rt_refcnt++;
205 				rtfree(nrt);
206 			}
207 		} else {
208 			/* the cmd must be RTM_ADD here */
209 			nrt->rt_refcnt--;
210 		}
211 	}
212 }
213 
214 /*
215  * Add ownaddr as loopback rtentry.  We previously add the route only if
216  * necessary (ex. on a p2p link).  However, since we now manage addresses
217  * separately from prefixes, we should always add the route.  We can't
218  * rely on the cloning mechanism from the corresponding interface route
219  * any more.
220  */
221 void
222 in6_ifaddloop(struct ifaddr *ifa)
223 {
224 	struct rtentry *rt;
225 
226 	/* If there is no loopback entry, allocate one. */
227 	rt = rtalloc1(ifa->ifa_addr, 0);
228 	if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0 ||
229 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
230 		in6_ifloop_request(RTM_ADD, ifa);
231 	if (rt != NULL)
232 		rt->rt_refcnt--;
233 }
234 
235 /*
236  * Remove loopback rtentry of ownaddr generated by in6_ifaddloop(),
237  * if it exists.
238  */
239 void
240 in6_ifremloop(struct ifaddr *ifa)
241 {
242 	struct in6_ifaddr *alt_ia = NULL, *ia;
243 	struct rtentry *rt;
244 	int ia_count = 0;
245 
246 	/*
247 	 * Some of BSD variants do not remove cloned routes
248 	 * from an interface direct route, when removing the direct route
249 	 * (see comments in net/net_osdep.h).  Even for variants that do remove
250 	 * cloned routes, they could fail to remove the cloned routes when
251 	 * we handle multple addresses that share a common prefix.
252 	 * So, we should remove the route corresponding to the deleted address.
253 	 */
254 
255 	/*
256 	 * Delete the entry only if exactly one ifaddr matches the
257 	 * address, ifa->ifa_addr.
258 	 *
259 	 * If more than one ifaddr matches, replace the ifaddr in
260 	 * the routing table, rt_ifa, with a different ifaddr than
261 	 * the one we are purging, ifa.  It is important to do
262 	 * this, or else the routing table can accumulate dangling
263 	 * pointers rt->rt_ifa->ifa_ifp to destroyed interfaces,
264 	 * which will lead to crashes, later.  (More than one ifaddr
265 	 * can match if we assign the same address to multiple---probably
266 	 * p2p---interfaces.)
267 	 *
268 	 * XXX An old comment at this place said, "we should avoid
269 	 * XXX such a configuration [i.e., interfaces with the same
270 	 * XXX addressed assigned --ed.] in IPv6...".  I do not
271 	 * XXX agree, especially now that I have fixed the dangling
272 	 * XXX ifp-pointers bug.
273 	 */
274 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
275 		if (!IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ia->ia_addr.sin6_addr))
276 			continue;
277 		if (ia->ia_ifp != ifa->ifa_ifp)
278 			alt_ia = ia;
279 		if (++ia_count > 1 && alt_ia != NULL)
280 			break;
281 	}
282 
283 	if (ia_count == 0)
284 		return;
285 
286 	if ((rt = rtalloc1(ifa->ifa_addr, 0)) == NULL)
287 		return;
288 	rt->rt_refcnt--;
289 
290 	/*
291 	 * Before deleting, check if a corresponding loopbacked
292 	 * host route surely exists.  With this check, we can avoid
293 	 * deleting an interface direct route whose destination is
294 	 * the same as the address being removed.  This can happen
295 	 * when removing a subnet-router anycast address on an
296 	 * interface attached to a shared medium.
297 	 */
298 	if ((rt->rt_flags & RTF_HOST) == 0 ||
299 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
300 		return;
301 
302 	/* If we cannot replace the route's ifaddr with the equivalent
303 	 * ifaddr of another interface, I believe it is safest to
304 	 * delete the route.
305 	 */
306 	if (ia_count == 1 || alt_ia == NULL)
307 		in6_ifloop_request(RTM_DELETE, ifa);
308 	else
309 		rt_replace_ifa(rt, &alt_ia->ia_ifa);
310 }
311 
312 int
313 in6_mask2len(struct in6_addr *mask, u_char *lim0)
314 {
315 	int x = 0, y;
316 	u_char *lim = lim0, *p;
317 
318 	/* ignore the scope_id part */
319 	if (lim0 == NULL || lim0 - (u_char *)mask > sizeof(*mask))
320 		lim = (u_char *)mask + sizeof(*mask);
321 	for (p = (u_char *)mask; p < lim; x++, p++) {
322 		if (*p != 0xff)
323 			break;
324 	}
325 	y = 0;
326 	if (p < lim) {
327 		for (y = 0; y < NBBY; y++) {
328 			if ((*p & (0x80 >> y)) == 0)
329 				break;
330 		}
331 	}
332 
333 	/*
334 	 * when the limit pointer is given, do a stricter check on the
335 	 * remaining bits.
336 	 */
337 	if (p < lim) {
338 		if (y != 0 && (*p & (0x00ff >> y)) != 0)
339 			return -1;
340 		for (p = p + 1; p < lim; p++)
341 			if (*p != 0)
342 				return -1;
343 	}
344 
345 	return x * NBBY + y;
346 }
347 
348 #define ifa2ia6(ifa)	((struct in6_ifaddr *)(ifa))
349 #define ia62ifa(ia6)	(&((ia6)->ia_ifa))
350 
351 static int
352 in6_control1(struct socket *so, u_long cmd, void *data, struct ifnet *ifp,
353     lwp_t *l)
354 {
355 	struct	in6_ifreq *ifr = (struct in6_ifreq *)data;
356 	struct	in6_ifaddr *ia = NULL;
357 	struct	in6_aliasreq *ifra = (struct in6_aliasreq *)data;
358 	struct sockaddr_in6 *sa6;
359 	int error;
360 
361 	switch (cmd) {
362 	/*
363 	 * XXX: Fix me, once we fix SIOCSIFADDR, SIOCIFDSTADDR, etc.
364 	 */
365 	case SIOCSIFADDR:
366 	case SIOCSIFDSTADDR:
367 #ifdef SIOCSIFCONF_X25
368 	case SIOCSIFCONF_X25:
369 #endif
370 		return EOPNOTSUPP;
371 	case SIOCGETSGCNT_IN6:
372 	case SIOCGETMIFCNT_IN6:
373 		return mrt6_ioctl(cmd, data);
374 	case SIOCGIFADDRPREF:
375 	case SIOCSIFADDRPREF:
376 		if (ifp == NULL)
377 			return EINVAL;
378 		return ifaddrpref_ioctl(so, cmd, data, ifp, l);
379 	}
380 
381 	if (ifp == NULL)
382 		return EOPNOTSUPP;
383 
384 	switch (cmd) {
385 	case SIOCSNDFLUSH_IN6:
386 	case SIOCSPFXFLUSH_IN6:
387 	case SIOCSRTRFLUSH_IN6:
388 	case SIOCSDEFIFACE_IN6:
389 	case SIOCSIFINFO_FLAGS:
390 	case SIOCSIFINFO_IN6:
391 		/* Privileged. */
392 		/* FALLTHROUGH */
393 	case OSIOCGIFINFO_IN6:
394 	case SIOCGIFINFO_IN6:
395 	case SIOCGDRLST_IN6:
396 	case SIOCGPRLST_IN6:
397 	case SIOCGNBRINFO_IN6:
398 	case SIOCGDEFIFACE_IN6:
399 		return nd6_ioctl(cmd, data, ifp);
400 	}
401 
402 	switch (cmd) {
403 	case SIOCSIFPREFIX_IN6:
404 	case SIOCDIFPREFIX_IN6:
405 	case SIOCAIFPREFIX_IN6:
406 	case SIOCCIFPREFIX_IN6:
407 	case SIOCSGIFPREFIX_IN6:
408 	case SIOCGIFPREFIX_IN6:
409 		log(LOG_NOTICE,
410 		    "prefix ioctls are now invalidated. "
411 		    "please use ifconfig.\n");
412 		return EOPNOTSUPP;
413 	}
414 
415 	switch (cmd) {
416 	case SIOCALIFADDR:
417 	case SIOCDLIFADDR:
418 		/* Privileged. */
419 		/* FALLTHROUGH */
420 	case SIOCGLIFADDR:
421 		return in6_lifaddr_ioctl(so, cmd, data, ifp, l);
422 	}
423 
424 	/*
425 	 * Find address for this interface, if it exists.
426 	 *
427 	 * In netinet code, we have checked ifra_addr in SIOCSIF*ADDR operation
428 	 * only, and used the first interface address as the target of other
429 	 * operations (without checking ifra_addr).  This was because netinet
430 	 * code/API assumed at most 1 interface address per interface.
431 	 * Since IPv6 allows a node to assign multiple addresses
432 	 * on a single interface, we almost always look and check the
433 	 * presence of ifra_addr, and reject invalid ones here.
434 	 * It also decreases duplicated code among SIOC*_IN6 operations.
435 	 */
436 	switch (cmd) {
437 	case SIOCAIFADDR_IN6:
438 #ifdef OSIOCAIFADDR_IN6
439 	case OSIOCAIFADDR_IN6:
440 #endif
441 #ifdef OSIOCSIFPHYADDR_IN6
442 	case OSIOCSIFPHYADDR_IN6:
443 #endif
444 	case SIOCSIFPHYADDR_IN6:
445 		sa6 = &ifra->ifra_addr;
446 		break;
447 	case SIOCSIFADDR_IN6:
448 	case SIOCGIFADDR_IN6:
449 	case SIOCSIFDSTADDR_IN6:
450 	case SIOCSIFNETMASK_IN6:
451 	case SIOCGIFDSTADDR_IN6:
452 	case SIOCGIFNETMASK_IN6:
453 	case SIOCDIFADDR_IN6:
454 	case SIOCGIFPSRCADDR_IN6:
455 	case SIOCGIFPDSTADDR_IN6:
456 	case SIOCGIFAFLAG_IN6:
457 	case SIOCSNDFLUSH_IN6:
458 	case SIOCSPFXFLUSH_IN6:
459 	case SIOCSRTRFLUSH_IN6:
460 	case SIOCGIFALIFETIME_IN6:
461 #ifdef OSIOCGIFALIFETIME_IN6
462 	case OSIOCGIFALIFETIME_IN6:
463 #endif
464 	case SIOCGIFSTAT_IN6:
465 	case SIOCGIFSTAT_ICMP6:
466 		sa6 = &ifr->ifr_addr;
467 		break;
468 	default:
469 		sa6 = NULL;
470 		break;
471 	}
472 	if (sa6 && sa6->sin6_family == AF_INET6) {
473 		if (sa6->sin6_scope_id != 0)
474 			error = sa6_embedscope(sa6, 0);
475 		else
476 			error = in6_setscope(&sa6->sin6_addr, ifp, NULL);
477 		if (error != 0)
478 			return error;
479 		ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
480 	} else
481 		ia = NULL;
482 
483 	switch (cmd) {
484 	case SIOCSIFADDR_IN6:
485 	case SIOCSIFDSTADDR_IN6:
486 	case SIOCSIFNETMASK_IN6:
487 		/*
488 		 * Since IPv6 allows a node to assign multiple addresses
489 		 * on a single interface, SIOCSIFxxx ioctls are deprecated.
490 		 */
491 		return EINVAL;
492 
493 	case SIOCDIFADDR_IN6:
494 		/*
495 		 * for IPv4, we look for existing in_ifaddr here to allow
496 		 * "ifconfig if0 delete" to remove the first IPv4 address on
497 		 * the interface.  For IPv6, as the spec allows multiple
498 		 * interface address from the day one, we consider "remove the
499 		 * first one" semantics to be not preferable.
500 		 */
501 		if (ia == NULL)
502 			return EADDRNOTAVAIL;
503 		/* FALLTHROUGH */
504 #ifdef OSIOCAIFADDR_IN6
505 	case OSIOCAIFADDR_IN6:
506 #endif
507 	case SIOCAIFADDR_IN6:
508 		/*
509 		 * We always require users to specify a valid IPv6 address for
510 		 * the corresponding operation.
511 		 */
512 		if (ifra->ifra_addr.sin6_family != AF_INET6 ||
513 		    ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6))
514 			return EAFNOSUPPORT;
515 		/* Privileged. */
516 
517 		break;
518 
519 	case SIOCGIFADDR_IN6:
520 		/* This interface is basically deprecated. use SIOCGIFCONF. */
521 		/* FALLTHROUGH */
522 	case SIOCGIFAFLAG_IN6:
523 	case SIOCGIFNETMASK_IN6:
524 	case SIOCGIFDSTADDR_IN6:
525 	case SIOCGIFALIFETIME_IN6:
526 #ifdef OSIOCGIFALIFETIME_IN6
527 	case OSIOCGIFALIFETIME_IN6:
528 #endif
529 		/* must think again about its semantics */
530 		if (ia == NULL)
531 			return EADDRNOTAVAIL;
532 		break;
533 	}
534 
535 	switch (cmd) {
536 
537 	case SIOCGIFADDR_IN6:
538 		ifr->ifr_addr = ia->ia_addr;
539 		if ((error = sa6_recoverscope(&ifr->ifr_addr)) != 0)
540 			return error;
541 		break;
542 
543 	case SIOCGIFDSTADDR_IN6:
544 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
545 			return EINVAL;
546 		/*
547 		 * XXX: should we check if ifa_dstaddr is NULL and return
548 		 * an error?
549 		 */
550 		ifr->ifr_dstaddr = ia->ia_dstaddr;
551 		if ((error = sa6_recoverscope(&ifr->ifr_dstaddr)) != 0)
552 			return error;
553 		break;
554 
555 	case SIOCGIFNETMASK_IN6:
556 		ifr->ifr_addr = ia->ia_prefixmask;
557 		break;
558 
559 	case SIOCGIFAFLAG_IN6:
560 		ifr->ifr_ifru.ifru_flags6 = ia->ia6_flags;
561 		break;
562 
563 	case SIOCGIFSTAT_IN6:
564 		if (ifp == NULL)
565 			return EINVAL;
566 		memset(&ifr->ifr_ifru.ifru_stat, 0,
567 		    sizeof(ifr->ifr_ifru.ifru_stat));
568 		ifr->ifr_ifru.ifru_stat =
569 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->in6_ifstat;
570 		break;
571 
572 	case SIOCGIFSTAT_ICMP6:
573 		if (ifp == NULL)
574 			return EINVAL;
575 		memset(&ifr->ifr_ifru.ifru_icmp6stat, 0,
576 		    sizeof(ifr->ifr_ifru.ifru_icmp6stat));
577 		ifr->ifr_ifru.ifru_icmp6stat =
578 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->icmp6_ifstat;
579 		break;
580 
581 #ifdef OSIOCGIFALIFETIME_IN6
582 	case OSIOCGIFALIFETIME_IN6:
583 #endif
584 	case SIOCGIFALIFETIME_IN6:
585 		ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
586 		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
587 			time_t maxexpire;
588 			struct in6_addrlifetime *retlt =
589 			    &ifr->ifr_ifru.ifru_lifetime;
590 
591 			/*
592 			 * XXX: adjust expiration time assuming time_t is
593 			 * signed.
594 			 */
595 			maxexpire = ((time_t)~0) &
596 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
597 			if (ia->ia6_lifetime.ia6t_vltime <
598 			    maxexpire - ia->ia6_updatetime) {
599 				retlt->ia6t_expire = ia->ia6_updatetime +
600 				    ia->ia6_lifetime.ia6t_vltime;
601 			} else
602 				retlt->ia6t_expire = maxexpire;
603 		}
604 		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
605 			time_t maxexpire;
606 			struct in6_addrlifetime *retlt =
607 			    &ifr->ifr_ifru.ifru_lifetime;
608 
609 			/*
610 			 * XXX: adjust expiration time assuming time_t is
611 			 * signed.
612 			 */
613 			maxexpire = ((time_t)~0) &
614 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
615 			if (ia->ia6_lifetime.ia6t_pltime <
616 			    maxexpire - ia->ia6_updatetime) {
617 				retlt->ia6t_preferred = ia->ia6_updatetime +
618 				    ia->ia6_lifetime.ia6t_pltime;
619 			} else
620 				retlt->ia6t_preferred = maxexpire;
621 		}
622 #ifdef OSIOCFIFALIFETIME_IN6
623 		if (cmd == OSIOCFIFALIFETIME_IN6)
624 			in6_addrlifetime_to_in6_addrlifetime50(
625 			    &ifr->ifru.ifru_lifetime);
626 #endif
627 		break;
628 
629 #ifdef OSIOCAIFADDR_IN6
630 	case OSIOCAIFADDR_IN6:
631 		in6_aliasreq50_to_in6_aliasreq(ifra);
632 		/*FALLTHROUGH*/
633 #endif
634 	case SIOCAIFADDR_IN6:
635 	{
636 		int i;
637 		struct nd_prefixctl pr0;
638 		struct nd_prefix *pr;
639 
640 		/* reject read-only flags */
641 		if ((ifra->ifra_flags & IN6_IFF_DUPLICATED) != 0 ||
642 		    (ifra->ifra_flags & IN6_IFF_DETACHED) != 0 ||
643 		    (ifra->ifra_flags & IN6_IFF_NODAD) != 0 ||
644 		    (ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0) {
645 			return EINVAL;
646 		}
647 		/*
648 		 * first, make or update the interface address structure,
649 		 * and link it to the list.
650 		 */
651 		if ((error = in6_update_ifa(ifp, ifra, ia, 0)) != 0)
652 			return error;
653 		if ((ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr))
654 		    == NULL) {
655 		    	/*
656 			 * this can happen when the user specify the 0 valid
657 			 * lifetime.
658 			 */
659 			break;
660 		}
661 
662 		/*
663 		 * then, make the prefix on-link on the interface.
664 		 * XXX: we'd rather create the prefix before the address, but
665 		 * we need at least one address to install the corresponding
666 		 * interface route, so we configure the address first.
667 		 */
668 
669 		/*
670 		 * convert mask to prefix length (prefixmask has already
671 		 * been validated in in6_update_ifa().
672 		 */
673 		memset(&pr0, 0, sizeof(pr0));
674 		pr0.ndpr_ifp = ifp;
675 		pr0.ndpr_plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
676 		    NULL);
677 		if (pr0.ndpr_plen == 128) {
678 			break;	/* we don't need to install a host route. */
679 		}
680 		pr0.ndpr_prefix = ifra->ifra_addr;
681 		/* apply the mask for safety. */
682 		for (i = 0; i < 4; i++) {
683 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
684 			    ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
685 		}
686 		/*
687 		 * XXX: since we don't have an API to set prefix (not address)
688 		 * lifetimes, we just use the same lifetimes as addresses.
689 		 * The (temporarily) installed lifetimes can be overridden by
690 		 * later advertised RAs (when accept_rtadv is non 0), which is
691 		 * an intended behavior.
692 		 */
693 		pr0.ndpr_raf_onlink = 1; /* should be configurable? */
694 		pr0.ndpr_raf_auto =
695 		    ((ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0);
696 		pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
697 		pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;
698 
699 		/* add the prefix if not yet. */
700 		if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
701 			/*
702 			 * nd6_prelist_add will install the corresponding
703 			 * interface route.
704 			 */
705 			if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
706 				return error;
707 			if (pr == NULL) {
708 				log(LOG_ERR, "nd6_prelist_add succeeded but "
709 				    "no prefix\n");
710 				return EINVAL; /* XXX panic here? */
711 			}
712 		}
713 
714 		/* relate the address to the prefix */
715 		if (ia->ia6_ndpr == NULL) {
716 			ia->ia6_ndpr = pr;
717 			pr->ndpr_refcnt++;
718 
719 			/*
720 			 * If this is the first autoconf address from the
721 			 * prefix, create a temporary address as well
722 			 * (when required).
723 			 */
724 			if ((ia->ia6_flags & IN6_IFF_AUTOCONF) &&
725 			    ip6_use_tempaddr && pr->ndpr_refcnt == 1) {
726 				int e;
727 				if ((e = in6_tmpifadd(ia, 1, 0)) != 0) {
728 					log(LOG_NOTICE, "in6_control: failed "
729 					    "to create a temporary address, "
730 					    "errno=%d\n", e);
731 				}
732 			}
733 		}
734 
735 		/*
736 		 * this might affect the status of autoconfigured addresses,
737 		 * that is, this address might make other addresses detached.
738 		 */
739 		pfxlist_onlink_check();
740 
741 #ifdef PFIL_HOOKS
742 		(void)pfil_run_hooks(&if_pfil, (struct mbuf **)SIOCAIFADDR_IN6,
743 		    ifp, PFIL_IFADDR);
744 #endif
745 
746 		break;
747 	}
748 
749 	case SIOCDIFADDR_IN6:
750 	{
751 		struct nd_prefix *pr;
752 
753 		/*
754 		 * If the address being deleted is the only one that owns
755 		 * the corresponding prefix, expire the prefix as well.
756 		 * XXX: theoretically, we don't have to worry about such
757 		 * relationship, since we separate the address management
758 		 * and the prefix management.  We do this, however, to provide
759 		 * as much backward compatibility as possible in terms of
760 		 * the ioctl operation.
761 		 * Note that in6_purgeaddr() will decrement ndpr_refcnt.
762 		 */
763 		pr = ia->ia6_ndpr;
764 		in6_purgeaddr(&ia->ia_ifa);
765 		if (pr && pr->ndpr_refcnt == 0)
766 			prelist_remove(pr);
767 #ifdef PFIL_HOOKS
768 		(void)pfil_run_hooks(&if_pfil, (struct mbuf **)SIOCDIFADDR_IN6,
769 		    ifp, PFIL_IFADDR);
770 #endif
771 		break;
772 	}
773 
774 	default:
775 		return ENOTTY;
776 	}
777 
778 	return 0;
779 }
780 
781 int
782 in6_control(struct socket *so, u_long cmd, void *data, struct ifnet *ifp,
783     struct lwp *l)
784 {
785 	int error, s;
786 
787 	switch (cmd) {
788 	case SIOCSNDFLUSH_IN6:
789 	case SIOCSPFXFLUSH_IN6:
790 	case SIOCSRTRFLUSH_IN6:
791 	case SIOCSDEFIFACE_IN6:
792 	case SIOCSIFINFO_FLAGS:
793 	case SIOCSIFINFO_IN6:
794 
795 	case SIOCALIFADDR:
796 	case SIOCDLIFADDR:
797 
798 	case SIOCDIFADDR_IN6:
799 #ifdef OSIOCAIFADDR_IN6
800 	case OSIOCAIFADDR_IN6:
801 #endif
802 	case SIOCAIFADDR_IN6:
803 		if (l == NULL || kauth_authorize_generic(l->l_cred,
804 		    KAUTH_GENERIC_ISSUSER, NULL))
805 			return EPERM;
806 		break;
807 	}
808 
809 	s = splnet();
810 	error = in6_control1(so , cmd, data, ifp, l);
811 	splx(s);
812 	return error;
813 }
814 
815 /*
816  * Update parameters of an IPv6 interface address.
817  * If necessary, a new entry is created and linked into address chains.
818  * This function is separated from in6_control().
819  * XXX: should this be performed under splnet()?
820  */
821 static int
822 in6_update_ifa1(struct ifnet *ifp, struct in6_aliasreq *ifra,
823     struct in6_ifaddr *ia, int flags)
824 {
825 	int error = 0, hostIsNew = 0, plen = -1;
826 	struct in6_ifaddr *oia;
827 	struct sockaddr_in6 dst6;
828 	struct in6_addrlifetime *lt;
829 	struct in6_multi_mship *imm;
830 	struct in6_multi *in6m_sol;
831 	struct rtentry *rt;
832 	int dad_delay;
833 
834 	in6m_sol = NULL;
835 
836 	/* Validate parameters */
837 	if (ifp == NULL || ifra == NULL) /* this maybe redundant */
838 		return EINVAL;
839 
840 	/*
841 	 * The destination address for a p2p link must have a family
842 	 * of AF_UNSPEC or AF_INET6.
843 	 */
844 	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
845 	    ifra->ifra_dstaddr.sin6_family != AF_INET6 &&
846 	    ifra->ifra_dstaddr.sin6_family != AF_UNSPEC)
847 		return EAFNOSUPPORT;
848 	/*
849 	 * validate ifra_prefixmask.  don't check sin6_family, netmask
850 	 * does not carry fields other than sin6_len.
851 	 */
852 	if (ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6))
853 		return EINVAL;
854 	/*
855 	 * Because the IPv6 address architecture is classless, we require
856 	 * users to specify a (non 0) prefix length (mask) for a new address.
857 	 * We also require the prefix (when specified) mask is valid, and thus
858 	 * reject a non-consecutive mask.
859 	 */
860 	if (ia == NULL && ifra->ifra_prefixmask.sin6_len == 0)
861 		return EINVAL;
862 	if (ifra->ifra_prefixmask.sin6_len != 0) {
863 		plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
864 		    (u_char *)&ifra->ifra_prefixmask +
865 		    ifra->ifra_prefixmask.sin6_len);
866 		if (plen <= 0)
867 			return EINVAL;
868 	} else {
869 		/*
870 		 * In this case, ia must not be NULL.  We just use its prefix
871 		 * length.
872 		 */
873 		plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
874 	}
875 	/*
876 	 * If the destination address on a p2p interface is specified,
877 	 * and the address is a scoped one, validate/set the scope
878 	 * zone identifier.
879 	 */
880 	dst6 = ifra->ifra_dstaddr;
881 	if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) != 0 &&
882 	    (dst6.sin6_family == AF_INET6)) {
883 		struct in6_addr in6_tmp;
884 		u_int32_t zoneid;
885 
886 		in6_tmp = dst6.sin6_addr;
887 		if (in6_setscope(&in6_tmp, ifp, &zoneid))
888 			return EINVAL; /* XXX: should be impossible */
889 
890 		if (dst6.sin6_scope_id != 0) {
891 			if (dst6.sin6_scope_id != zoneid)
892 				return EINVAL;
893 		} else		/* user omit to specify the ID. */
894 			dst6.sin6_scope_id = zoneid;
895 
896 		/* convert into the internal form */
897 		if (sa6_embedscope(&dst6, 0))
898 			return EINVAL; /* XXX: should be impossible */
899 	}
900 	/*
901 	 * The destination address can be specified only for a p2p or a
902 	 * loopback interface.  If specified, the corresponding prefix length
903 	 * must be 128.
904 	 */
905 	if (ifra->ifra_dstaddr.sin6_family == AF_INET6) {
906 #ifdef FORCE_P2PPLEN
907 		int i;
908 #endif
909 
910 		if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) == 0) {
911 			/* XXX: noisy message */
912 			nd6log((LOG_INFO, "in6_update_ifa: a destination can "
913 			    "be specified for a p2p or a loopback IF only\n"));
914 			return EINVAL;
915 		}
916 		if (plen != 128) {
917 			nd6log((LOG_INFO, "in6_update_ifa: prefixlen should "
918 			    "be 128 when dstaddr is specified\n"));
919 #ifdef FORCE_P2PPLEN
920 			/*
921 			 * To be compatible with old configurations,
922 			 * such as ifconfig gif0 inet6 2001::1 2001::2
923 			 * prefixlen 126, we override the specified
924 			 * prefixmask as if the prefix length was 128.
925 			 */
926 			ifra->ifra_prefixmask.sin6_len =
927 			    sizeof(struct sockaddr_in6);
928 			for (i = 0; i < 4; i++)
929 				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i] =
930 				    0xffffffff;
931 			plen = 128;
932 #else
933 			return EINVAL;
934 #endif
935 		}
936 	}
937 	/* lifetime consistency check */
938 	lt = &ifra->ifra_lifetime;
939 	if (lt->ia6t_pltime > lt->ia6t_vltime)
940 		return EINVAL;
941 	if (lt->ia6t_vltime == 0) {
942 		/*
943 		 * the following log might be noisy, but this is a typical
944 		 * configuration mistake or a tool's bug.
945 		 */
946 		nd6log((LOG_INFO,
947 		    "in6_update_ifa: valid lifetime is 0 for %s\n",
948 		    ip6_sprintf(&ifra->ifra_addr.sin6_addr)));
949 
950 		if (ia == NULL)
951 			return 0; /* there's nothing to do */
952 	}
953 
954 	/*
955 	 * If this is a new address, allocate a new ifaddr and link it
956 	 * into chains.
957 	 */
958 	if (ia == NULL) {
959 		hostIsNew = 1;
960 		/*
961 		 * When in6_update_ifa() is called in a process of a received
962 		 * RA, it is called under an interrupt context.  So, we should
963 		 * call malloc with M_NOWAIT.
964 		 */
965 		ia = (struct in6_ifaddr *) malloc(sizeof(*ia), M_IFADDR,
966 		    M_NOWAIT);
967 		if (ia == NULL)
968 			return ENOBUFS;
969 		memset(ia, 0, sizeof(*ia));
970 		LIST_INIT(&ia->ia6_memberships);
971 		/* Initialize the address and masks, and put time stamp */
972 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
973 		ia->ia_addr.sin6_family = AF_INET6;
974 		ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
975 		ia->ia6_createtime = time_second;
976 		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
977 			/*
978 			 * XXX: some functions expect that ifa_dstaddr is not
979 			 * NULL for p2p interfaces.
980 			 */
981 			ia->ia_ifa.ifa_dstaddr =
982 			    (struct sockaddr *)&ia->ia_dstaddr;
983 		} else {
984 			ia->ia_ifa.ifa_dstaddr = NULL;
985 		}
986 		ia->ia_ifa.ifa_netmask =
987 		    (struct sockaddr *)&ia->ia_prefixmask;
988 
989 		ia->ia_ifp = ifp;
990 		if ((oia = in6_ifaddr) != NULL) {
991 			for ( ; oia->ia_next; oia = oia->ia_next)
992 				continue;
993 			oia->ia_next = ia;
994 		} else
995 			in6_ifaddr = ia;
996 		/* gain a refcnt for the link from in6_ifaddr */
997 		IFAREF(&ia->ia_ifa);
998 
999 		ifa_insert(ifp, &ia->ia_ifa);
1000 	}
1001 
1002 	/* update timestamp */
1003 	ia->ia6_updatetime = time_second;
1004 
1005 	/* set prefix mask */
1006 	if (ifra->ifra_prefixmask.sin6_len) {
1007 		/*
1008 		 * We prohibit changing the prefix length of an existing
1009 		 * address, because
1010 		 * + such an operation should be rare in IPv6, and
1011 		 * + the operation would confuse prefix management.
1012 		 */
1013 		if (ia->ia_prefixmask.sin6_len &&
1014 		    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL) != plen) {
1015 			nd6log((LOG_INFO, "in6_update_ifa: the prefix length of an"
1016 			    " existing (%s) address should not be changed\n",
1017 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1018 			error = EINVAL;
1019 			goto unlink;
1020 		}
1021 		ia->ia_prefixmask = ifra->ifra_prefixmask;
1022 	}
1023 
1024 	/*
1025 	 * If a new destination address is specified, scrub the old one and
1026 	 * install the new destination.  Note that the interface must be
1027 	 * p2p or loopback (see the check above.)
1028 	 */
1029 	if (dst6.sin6_family == AF_INET6 &&
1030 	    !IN6_ARE_ADDR_EQUAL(&dst6.sin6_addr, &ia->ia_dstaddr.sin6_addr)) {
1031 		if ((ia->ia_flags & IFA_ROUTE) != 0 &&
1032 		    rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST) != 0) {
1033 			nd6log((LOG_ERR, "in6_update_ifa: failed to remove "
1034 			    "a route to the old destination: %s\n",
1035 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1036 			/* proceed anyway... */
1037 		} else
1038 			ia->ia_flags &= ~IFA_ROUTE;
1039 		ia->ia_dstaddr = dst6;
1040 	}
1041 
1042 	/*
1043 	 * Set lifetimes.  We do not refer to ia6t_expire and ia6t_preferred
1044 	 * to see if the address is deprecated or invalidated, but initialize
1045 	 * these members for applications.
1046 	 */
1047 	ia->ia6_lifetime = ifra->ifra_lifetime;
1048 	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
1049 		ia->ia6_lifetime.ia6t_expire =
1050 		    time_second + ia->ia6_lifetime.ia6t_vltime;
1051 	} else
1052 		ia->ia6_lifetime.ia6t_expire = 0;
1053 	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
1054 		ia->ia6_lifetime.ia6t_preferred =
1055 		    time_second + ia->ia6_lifetime.ia6t_pltime;
1056 	} else
1057 		ia->ia6_lifetime.ia6t_preferred = 0;
1058 
1059 	/* reset the interface and routing table appropriately. */
1060 	if ((error = in6_ifinit(ifp, ia, &ifra->ifra_addr, hostIsNew)) != 0)
1061 		goto unlink;
1062 
1063 	/*
1064 	 * configure address flags.
1065 	 */
1066 	ia->ia6_flags = ifra->ifra_flags;
1067 	/*
1068 	 * backward compatibility - if IN6_IFF_DEPRECATED is set from the
1069 	 * userland, make it deprecated.
1070 	 */
1071 	if ((ifra->ifra_flags & IN6_IFF_DEPRECATED) != 0) {
1072 		ia->ia6_lifetime.ia6t_pltime = 0;
1073 		ia->ia6_lifetime.ia6t_preferred = time_second;
1074 	}
1075 
1076 	/*
1077 	 * Make the address tentative before joining multicast addresses,
1078 	 * so that corresponding MLD responses would not have a tentative
1079 	 * source address.
1080 	 */
1081 	ia->ia6_flags &= ~IN6_IFF_DUPLICATED;	/* safety */
1082 	if (hostIsNew && in6if_do_dad(ifp))
1083 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
1084 
1085 	/*
1086 	 * We are done if we have simply modified an existing address.
1087 	 */
1088 	if (!hostIsNew)
1089 		return error;
1090 
1091 	/*
1092 	 * Beyond this point, we should call in6_purgeaddr upon an error,
1093 	 * not just go to unlink.
1094 	 */
1095 
1096 	/* join necessary multicast groups */
1097 	if ((ifp->if_flags & IFF_MULTICAST) != 0) {
1098 		struct sockaddr_in6 mltaddr, mltmask;
1099 		struct in6_addr llsol;
1100 
1101 		/* join solicited multicast addr for new host id */
1102 		memset(&llsol, 0, sizeof(struct in6_addr));
1103 		llsol.s6_addr16[0] = htons(0xff02);
1104 		llsol.s6_addr32[1] = 0;
1105 		llsol.s6_addr32[2] = htonl(1);
1106 		llsol.s6_addr32[3] = ifra->ifra_addr.sin6_addr.s6_addr32[3];
1107 		llsol.s6_addr8[12] = 0xff;
1108 		if ((error = in6_setscope(&llsol, ifp, NULL)) != 0) {
1109 			/* XXX: should not happen */
1110 			log(LOG_ERR, "in6_update_ifa: "
1111 			    "in6_setscope failed\n");
1112 			goto cleanup;
1113 		}
1114 		dad_delay = 0;
1115 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1116 			/*
1117 			 * We need a random delay for DAD on the address
1118 			 * being configured.  It also means delaying
1119 			 * transmission of the corresponding MLD report to
1120 			 * avoid report collision.
1121 			 * [draft-ietf-ipv6-rfc2462bis-02.txt]
1122 			 */
1123 			dad_delay = cprng_fast32() %
1124 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1125 		}
1126 
1127 #define	MLTMASK_LEN  4	/* mltmask's masklen (=32bit=4octet) */
1128 		/* join solicited multicast addr for new host id */
1129 		imm = in6_joingroup(ifp, &llsol, &error, dad_delay);
1130 		if (!imm) {
1131 			nd6log((LOG_ERR,
1132 			    "in6_update_ifa: addmulti "
1133 			    "failed for %s on %s (errno=%d)\n",
1134 			    ip6_sprintf(&llsol), if_name(ifp), error));
1135 			goto cleanup;
1136 		}
1137 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1138 		in6m_sol = imm->i6mm_maddr;
1139 
1140 		sockaddr_in6_init(&mltmask, &in6mask32, 0, 0, 0);
1141 
1142 		/*
1143 		 * join link-local all-nodes address
1144 		 */
1145 		sockaddr_in6_init(&mltaddr, &in6addr_linklocal_allnodes,
1146 		    0, 0, 0);
1147 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1148 			goto cleanup; /* XXX: should not fail */
1149 
1150 		/*
1151 		 * XXX: do we really need this automatic routes?
1152 		 * We should probably reconsider this stuff.  Most applications
1153 		 * actually do not need the routes, since they usually specify
1154 		 * the outgoing interface.
1155 		 */
1156 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1157 		if (rt) {
1158 			if (memcmp(&mltaddr.sin6_addr,
1159 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1160 			    MLTMASK_LEN)) {
1161 				RTFREE(rt);
1162 				rt = NULL;
1163 			} else if (rt->rt_ifp != ifp) {
1164 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1165 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1166 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1167 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1168 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1169 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1170 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1171 				rt_replace_ifa(rt, &ia->ia_ifa);
1172 				rt->rt_ifp = ifp;
1173 			}
1174 		}
1175 		if (!rt) {
1176 			struct rt_addrinfo info;
1177 
1178 			memset(&info, 0, sizeof(info));
1179 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1180 			info.rti_info[RTAX_GATEWAY] =
1181 			    (struct sockaddr *)&ia->ia_addr;
1182 			info.rti_info[RTAX_NETMASK] =
1183 			    (struct sockaddr *)&mltmask;
1184 			info.rti_info[RTAX_IFA] =
1185 			    (struct sockaddr *)&ia->ia_addr;
1186 			/* XXX: we need RTF_CLONING to fake nd6_rtrequest */
1187 			info.rti_flags = RTF_UP | RTF_CLONING;
1188 			error = rtrequest1(RTM_ADD, &info, NULL);
1189 			if (error)
1190 				goto cleanup;
1191 		} else {
1192 			RTFREE(rt);
1193 		}
1194 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1195 		if (!imm) {
1196 			nd6log((LOG_WARNING,
1197 			    "in6_update_ifa: addmulti failed for "
1198 			    "%s on %s (errno=%d)\n",
1199 			    ip6_sprintf(&mltaddr.sin6_addr),
1200 			    if_name(ifp), error));
1201 			goto cleanup;
1202 		}
1203 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1204 
1205 		/*
1206 		 * join node information group address
1207 		 */
1208 		dad_delay = 0;
1209 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1210 			/*
1211 			 * The spec doesn't say anything about delay for this
1212 			 * group, but the same logic should apply.
1213 			 */
1214 			dad_delay = cprng_fast32() %
1215 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1216 		}
1217 		if (in6_nigroup(ifp, hostname, hostnamelen, &mltaddr) != 0)
1218 			;
1219 		else if ((imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error,
1220 		          dad_delay)) == NULL) { /* XXX jinmei */
1221 			nd6log((LOG_WARNING, "in6_update_ifa: "
1222 			    "addmulti failed for %s on %s (errno=%d)\n",
1223 			    ip6_sprintf(&mltaddr.sin6_addr),
1224 			    if_name(ifp), error));
1225 			/* XXX not very fatal, go on... */
1226 		} else {
1227 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1228 		}
1229 
1230 
1231 		/*
1232 		 * join interface-local all-nodes address.
1233 		 * (ff01::1%ifN, and ff01::%ifN/32)
1234 		 */
1235 		mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
1236 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1237 			goto cleanup; /* XXX: should not fail */
1238 
1239 		/* XXX: again, do we really need the route? */
1240 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1241 		if (rt) {
1242 			/* 32bit came from "mltmask" */
1243 			if (memcmp(&mltaddr.sin6_addr,
1244 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1245 			    32 / NBBY)) {
1246 				RTFREE(rt);
1247 				rt = NULL;
1248 			} else if (rt->rt_ifp != ifp) {
1249 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1250 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1251 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1252 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1253 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1254 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1255 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1256 				rt_replace_ifa(rt, &ia->ia_ifa);
1257 				rt->rt_ifp = ifp;
1258 			}
1259 		}
1260 		if (!rt) {
1261 			struct rt_addrinfo info;
1262 
1263 			memset(&info, 0, sizeof(info));
1264 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1265 			info.rti_info[RTAX_GATEWAY] =
1266 			    (struct sockaddr *)&ia->ia_addr;
1267 			info.rti_info[RTAX_NETMASK] =
1268 			    (struct sockaddr *)&mltmask;
1269 			info.rti_info[RTAX_IFA] =
1270 			    (struct sockaddr *)&ia->ia_addr;
1271 			info.rti_flags = RTF_UP | RTF_CLONING;
1272 			error = rtrequest1(RTM_ADD, &info, NULL);
1273 			if (error)
1274 				goto cleanup;
1275 #undef	MLTMASK_LEN
1276 		} else {
1277 			RTFREE(rt);
1278 		}
1279 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1280 		if (!imm) {
1281 			nd6log((LOG_WARNING, "in6_update_ifa: "
1282 			    "addmulti failed for %s on %s (errno=%d)\n",
1283 			    ip6_sprintf(&mltaddr.sin6_addr),
1284 			    if_name(ifp), error));
1285 			goto cleanup;
1286 		} else {
1287 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1288 		}
1289 	}
1290 
1291 	/*
1292 	 * Perform DAD, if needed.
1293 	 * XXX It may be of use, if we can administratively
1294 	 * disable DAD.
1295 	 */
1296 	if (hostIsNew && in6if_do_dad(ifp) &&
1297 	    ((ifra->ifra_flags & IN6_IFF_NODAD) == 0) &&
1298 	    (ia->ia6_flags & IN6_IFF_TENTATIVE))
1299 	{
1300 		int mindelay, maxdelay;
1301 
1302 		dad_delay = 0;
1303 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1304 			/*
1305 			 * We need to impose a delay before sending an NS
1306 			 * for DAD.  Check if we also needed a delay for the
1307 			 * corresponding MLD message.  If we did, the delay
1308 			 * should be larger than the MLD delay (this could be
1309 			 * relaxed a bit, but this simple logic is at least
1310 			 * safe).
1311 			 */
1312 			mindelay = 0;
1313 			if (in6m_sol != NULL &&
1314 			    in6m_sol->in6m_state == MLD_REPORTPENDING) {
1315 				mindelay = in6m_sol->in6m_timer;
1316 			}
1317 			maxdelay = MAX_RTR_SOLICITATION_DELAY * hz;
1318 			if (maxdelay - mindelay == 0)
1319 				dad_delay = 0;
1320 			else {
1321 				dad_delay =
1322 				    (cprng_fast32() % (maxdelay - mindelay)) +
1323 				    mindelay;
1324 			}
1325 		}
1326 		nd6_dad_start(&ia->ia_ifa, dad_delay);
1327 	}
1328 
1329 	return error;
1330 
1331   unlink:
1332 	/*
1333 	 * XXX: if a change of an existing address failed, keep the entry
1334 	 * anyway.
1335 	 */
1336 	if (hostIsNew)
1337 		in6_unlink_ifa(ia, ifp);
1338 	return error;
1339 
1340   cleanup:
1341 	in6_purgeaddr(&ia->ia_ifa);
1342 	return error;
1343 }
1344 
1345 int
1346 in6_update_ifa(struct ifnet *ifp, struct in6_aliasreq *ifra,
1347     struct in6_ifaddr *ia, int flags)
1348 {
1349 	int rc, s;
1350 
1351 	s = splnet();
1352 	rc = in6_update_ifa1(ifp, ifra, ia, flags);
1353 	splx(s);
1354 	return rc;
1355 }
1356 
1357 void
1358 in6_purgeaddr(struct ifaddr *ifa)
1359 {
1360 	struct ifnet *ifp = ifa->ifa_ifp;
1361 	struct in6_ifaddr *ia = (struct in6_ifaddr *) ifa;
1362 	struct in6_multi_mship *imm;
1363 
1364 	/* stop DAD processing */
1365 	nd6_dad_stop(ifa);
1366 
1367 	/*
1368 	 * delete route to the destination of the address being purged.
1369 	 * The interface must be p2p or loopback in this case.
1370 	 */
1371 	if ((ia->ia_flags & IFA_ROUTE) != 0 && ia->ia_dstaddr.sin6_len != 0) {
1372 		int e;
1373 
1374 		if ((e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
1375 		    != 0) {
1376 			log(LOG_ERR, "in6_purgeaddr: failed to remove "
1377 			    "a route to the p2p destination: %s on %s, "
1378 			    "errno=%d\n",
1379 			    ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
1380 			    e);
1381 			/* proceed anyway... */
1382 		} else
1383 			ia->ia_flags &= ~IFA_ROUTE;
1384 	}
1385 
1386 	/* Remove ownaddr's loopback rtentry, if it exists. */
1387 	in6_ifremloop(&(ia->ia_ifa));
1388 
1389 	/*
1390 	 * leave from multicast groups we have joined for the interface
1391 	 */
1392 	while ((imm = LIST_FIRST(&ia->ia6_memberships)) != NULL) {
1393 		LIST_REMOVE(imm, i6mm_chain);
1394 		in6_leavegroup(imm);
1395 	}
1396 
1397 	in6_unlink_ifa(ia, ifp);
1398 }
1399 
1400 static void
1401 in6_unlink_ifa(struct in6_ifaddr *ia, struct ifnet *ifp)
1402 {
1403 	struct in6_ifaddr *oia;
1404 	int	s = splnet();
1405 
1406 	ifa_remove(ifp, &ia->ia_ifa);
1407 
1408 	oia = ia;
1409 	if (oia == (ia = in6_ifaddr))
1410 		in6_ifaddr = ia->ia_next;
1411 	else {
1412 		while (ia->ia_next && (ia->ia_next != oia))
1413 			ia = ia->ia_next;
1414 		if (ia->ia_next)
1415 			ia->ia_next = oia->ia_next;
1416 		else {
1417 			/* search failed */
1418 			printf("Couldn't unlink in6_ifaddr from in6_ifaddr\n");
1419 		}
1420 	}
1421 
1422 	/*
1423 	 * XXX thorpej@NetBSD.org -- if the interface is going
1424 	 * XXX away, don't save the multicast entries, delete them!
1425 	 */
1426 	if (LIST_EMPTY(&oia->ia6_multiaddrs))
1427 		;
1428 	else if (oia->ia_ifa.ifa_ifp->if_output == if_nulloutput) {
1429 		struct in6_multi *in6m, *next;
1430 
1431 		for (in6m = LIST_FIRST(&oia->ia6_multiaddrs); in6m != NULL;
1432 		     in6m = next) {
1433 			next = LIST_NEXT(in6m, in6m_entry);
1434 			in6_delmulti(in6m);
1435 		}
1436 	} else
1437 		in6_savemkludge(oia);
1438 
1439 	/*
1440 	 * Release the reference to the base prefix.  There should be a
1441 	 * positive reference.
1442 	 */
1443 	if (oia->ia6_ndpr == NULL) {
1444 		nd6log((LOG_NOTICE, "in6_unlink_ifa: autoconf'ed address "
1445 		    "%p has no prefix\n", oia));
1446 	} else {
1447 		oia->ia6_ndpr->ndpr_refcnt--;
1448 		oia->ia6_ndpr = NULL;
1449 	}
1450 
1451 	/*
1452 	 * Also, if the address being removed is autoconf'ed, call
1453 	 * pfxlist_onlink_check() since the release might affect the status of
1454 	 * other (detached) addresses.
1455 	 */
1456 	if ((oia->ia6_flags & IN6_IFF_AUTOCONF) != 0)
1457 		pfxlist_onlink_check();
1458 
1459 	/*
1460 	 * release another refcnt for the link from in6_ifaddr.
1461 	 * Note that we should decrement the refcnt at least once for all *BSD.
1462 	 */
1463 	IFAFREE(&oia->ia_ifa);
1464 
1465 	splx(s);
1466 }
1467 
1468 void
1469 in6_purgeif(struct ifnet *ifp)
1470 {
1471 	if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr);
1472 
1473 	in6_ifdetach(ifp);
1474 }
1475 
1476 /*
1477  * SIOC[GAD]LIFADDR.
1478  *	SIOCGLIFADDR: get first address. (?)
1479  *	SIOCGLIFADDR with IFLR_PREFIX:
1480  *		get first address that matches the specified prefix.
1481  *	SIOCALIFADDR: add the specified address.
1482  *	SIOCALIFADDR with IFLR_PREFIX:
1483  *		add the specified prefix, filling hostid part from
1484  *		the first link-local address.  prefixlen must be <= 64.
1485  *	SIOCDLIFADDR: delete the specified address.
1486  *	SIOCDLIFADDR with IFLR_PREFIX:
1487  *		delete the first address that matches the specified prefix.
1488  * return values:
1489  *	EINVAL on invalid parameters
1490  *	EADDRNOTAVAIL on prefix match failed/specified address not found
1491  *	other values may be returned from in6_ioctl()
1492  *
1493  * NOTE: SIOCALIFADDR(with IFLR_PREFIX set) allows prefixlen less than 64.
1494  * this is to accommodate address naming scheme other than RFC2374,
1495  * in the future.
1496  * RFC2373 defines interface id to be 64bit, but it allows non-RFC2374
1497  * address encoding scheme. (see figure on page 8)
1498  */
1499 static int
1500 in6_lifaddr_ioctl(struct socket *so, u_long cmd, void *data,
1501 	struct ifnet *ifp, struct lwp *l)
1502 {
1503 	struct in6_ifaddr *ia;
1504 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
1505 	struct ifaddr *ifa;
1506 	struct sockaddr *sa;
1507 
1508 	/* sanity checks */
1509 	if (!data || !ifp) {
1510 		panic("invalid argument to in6_lifaddr_ioctl");
1511 		/* NOTREACHED */
1512 	}
1513 
1514 	switch (cmd) {
1515 	case SIOCGLIFADDR:
1516 		/* address must be specified on GET with IFLR_PREFIX */
1517 		if ((iflr->flags & IFLR_PREFIX) == 0)
1518 			break;
1519 		/* FALLTHROUGH */
1520 	case SIOCALIFADDR:
1521 	case SIOCDLIFADDR:
1522 		/* address must be specified on ADD and DELETE */
1523 		sa = (struct sockaddr *)&iflr->addr;
1524 		if (sa->sa_family != AF_INET6)
1525 			return EINVAL;
1526 		if (sa->sa_len != sizeof(struct sockaddr_in6))
1527 			return EINVAL;
1528 		/* XXX need improvement */
1529 		sa = (struct sockaddr *)&iflr->dstaddr;
1530 		if (sa->sa_family && sa->sa_family != AF_INET6)
1531 			return EINVAL;
1532 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in6))
1533 			return EINVAL;
1534 		break;
1535 	default: /* shouldn't happen */
1536 #if 0
1537 		panic("invalid cmd to in6_lifaddr_ioctl");
1538 		/* NOTREACHED */
1539 #else
1540 		return EOPNOTSUPP;
1541 #endif
1542 	}
1543 	if (sizeof(struct in6_addr) * NBBY < iflr->prefixlen)
1544 		return EINVAL;
1545 
1546 	switch (cmd) {
1547 	case SIOCALIFADDR:
1548 	    {
1549 		struct in6_aliasreq ifra;
1550 		struct in6_addr *xhostid = NULL;
1551 		int prefixlen;
1552 
1553 		if ((iflr->flags & IFLR_PREFIX) != 0) {
1554 			struct sockaddr_in6 *sin6;
1555 
1556 			/*
1557 			 * xhostid is to fill in the hostid part of the
1558 			 * address.  xhostid points to the first link-local
1559 			 * address attached to the interface.
1560 			 */
1561 			ia = in6ifa_ifpforlinklocal(ifp, 0);
1562 			if (ia == NULL)
1563 				return EADDRNOTAVAIL;
1564 			xhostid = IFA_IN6(&ia->ia_ifa);
1565 
1566 		 	/* prefixlen must be <= 64. */
1567 			if (64 < iflr->prefixlen)
1568 				return EINVAL;
1569 			prefixlen = iflr->prefixlen;
1570 
1571 			/* hostid part must be zero. */
1572 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1573 			if (sin6->sin6_addr.s6_addr32[2] != 0
1574 			 || sin6->sin6_addr.s6_addr32[3] != 0) {
1575 				return EINVAL;
1576 			}
1577 		} else
1578 			prefixlen = iflr->prefixlen;
1579 
1580 		/* copy args to in6_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
1581 		memset(&ifra, 0, sizeof(ifra));
1582 		memcpy(ifra.ifra_name, iflr->iflr_name, sizeof(ifra.ifra_name));
1583 
1584 		memcpy(&ifra.ifra_addr, &iflr->addr,
1585 		    ((struct sockaddr *)&iflr->addr)->sa_len);
1586 		if (xhostid) {
1587 			/* fill in hostid part */
1588 			ifra.ifra_addr.sin6_addr.s6_addr32[2] =
1589 			    xhostid->s6_addr32[2];
1590 			ifra.ifra_addr.sin6_addr.s6_addr32[3] =
1591 			    xhostid->s6_addr32[3];
1592 		}
1593 
1594 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) { /* XXX */
1595 			memcpy(&ifra.ifra_dstaddr, &iflr->dstaddr,
1596 			    ((struct sockaddr *)&iflr->dstaddr)->sa_len);
1597 			if (xhostid) {
1598 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[2] =
1599 				    xhostid->s6_addr32[2];
1600 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[3] =
1601 				    xhostid->s6_addr32[3];
1602 			}
1603 		}
1604 
1605 		ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
1606 		in6_prefixlen2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);
1607 
1608 		ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
1609 		ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
1610 		ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
1611 		return in6_control(so, SIOCAIFADDR_IN6, &ifra, ifp, l);
1612 	    }
1613 	case SIOCGLIFADDR:
1614 	case SIOCDLIFADDR:
1615 	    {
1616 		struct in6_addr mask, candidate, match;
1617 		struct sockaddr_in6 *sin6;
1618 		int cmp;
1619 
1620 		memset(&mask, 0, sizeof(mask));
1621 		if (iflr->flags & IFLR_PREFIX) {
1622 			/* lookup a prefix rather than address. */
1623 			in6_prefixlen2mask(&mask, iflr->prefixlen);
1624 
1625 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1626 			memcpy(&match, &sin6->sin6_addr, sizeof(match));
1627 			match.s6_addr32[0] &= mask.s6_addr32[0];
1628 			match.s6_addr32[1] &= mask.s6_addr32[1];
1629 			match.s6_addr32[2] &= mask.s6_addr32[2];
1630 			match.s6_addr32[3] &= mask.s6_addr32[3];
1631 
1632 			/* if you set extra bits, that's wrong */
1633 			if (memcmp(&match, &sin6->sin6_addr, sizeof(match)))
1634 				return EINVAL;
1635 
1636 			cmp = 1;
1637 		} else {
1638 			if (cmd == SIOCGLIFADDR) {
1639 				/* on getting an address, take the 1st match */
1640 				cmp = 0;	/* XXX */
1641 			} else {
1642 				/* on deleting an address, do exact match */
1643 				in6_prefixlen2mask(&mask, 128);
1644 				sin6 = (struct sockaddr_in6 *)&iflr->addr;
1645 				memcpy(&match, &sin6->sin6_addr, sizeof(match));
1646 
1647 				cmp = 1;
1648 			}
1649 		}
1650 
1651 		IFADDR_FOREACH(ifa, ifp) {
1652 			if (ifa->ifa_addr->sa_family != AF_INET6)
1653 				continue;
1654 			if (!cmp)
1655 				break;
1656 
1657 			/*
1658 			 * XXX: this is adhoc, but is necessary to allow
1659 			 * a user to specify fe80::/64 (not /10) for a
1660 			 * link-local address.
1661 			 */
1662 			memcpy(&candidate, IFA_IN6(ifa), sizeof(candidate));
1663 			in6_clearscope(&candidate);
1664 			candidate.s6_addr32[0] &= mask.s6_addr32[0];
1665 			candidate.s6_addr32[1] &= mask.s6_addr32[1];
1666 			candidate.s6_addr32[2] &= mask.s6_addr32[2];
1667 			candidate.s6_addr32[3] &= mask.s6_addr32[3];
1668 			if (IN6_ARE_ADDR_EQUAL(&candidate, &match))
1669 				break;
1670 		}
1671 		if (!ifa)
1672 			return EADDRNOTAVAIL;
1673 		ia = ifa2ia6(ifa);
1674 
1675 		if (cmd == SIOCGLIFADDR) {
1676 			int error;
1677 
1678 			/* fill in the if_laddrreq structure */
1679 			memcpy(&iflr->addr, &ia->ia_addr, ia->ia_addr.sin6_len);
1680 			error = sa6_recoverscope(
1681 			    (struct sockaddr_in6 *)&iflr->addr);
1682 			if (error != 0)
1683 				return error;
1684 
1685 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1686 				memcpy(&iflr->dstaddr, &ia->ia_dstaddr,
1687 				    ia->ia_dstaddr.sin6_len);
1688 				error = sa6_recoverscope(
1689 				    (struct sockaddr_in6 *)&iflr->dstaddr);
1690 				if (error != 0)
1691 					return error;
1692 			} else
1693 				memset(&iflr->dstaddr, 0, sizeof(iflr->dstaddr));
1694 
1695 			iflr->prefixlen =
1696 			    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
1697 
1698 			iflr->flags = ia->ia6_flags;	/* XXX */
1699 
1700 			return 0;
1701 		} else {
1702 			struct in6_aliasreq ifra;
1703 
1704 			/* fill in6_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
1705 			memset(&ifra, 0, sizeof(ifra));
1706 			memcpy(ifra.ifra_name, iflr->iflr_name,
1707 			    sizeof(ifra.ifra_name));
1708 
1709 			memcpy(&ifra.ifra_addr, &ia->ia_addr,
1710 			    ia->ia_addr.sin6_len);
1711 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1712 				memcpy(&ifra.ifra_dstaddr, &ia->ia_dstaddr,
1713 				    ia->ia_dstaddr.sin6_len);
1714 			} else {
1715 				memset(&ifra.ifra_dstaddr, 0,
1716 				    sizeof(ifra.ifra_dstaddr));
1717 			}
1718 			memcpy(&ifra.ifra_dstaddr, &ia->ia_prefixmask,
1719 			    ia->ia_prefixmask.sin6_len);
1720 
1721 			ifra.ifra_flags = ia->ia6_flags;
1722 			return in6_control(so, SIOCDIFADDR_IN6, &ifra, ifp, l);
1723 		}
1724 	    }
1725 	}
1726 
1727 	return EOPNOTSUPP;	/* just for safety */
1728 }
1729 
1730 /*
1731  * Initialize an interface's internet6 address
1732  * and routing table entry.
1733  */
1734 static int
1735 in6_ifinit(struct ifnet *ifp, struct in6_ifaddr *ia,
1736 	const struct sockaddr_in6 *sin6, int newhost)
1737 {
1738 	int	error = 0, plen, ifacount = 0;
1739 	int	s = splnet();
1740 	struct ifaddr *ifa;
1741 
1742 	/*
1743 	 * Give the interface a chance to initialize
1744 	 * if this is its first address,
1745 	 * and to validate the address if necessary.
1746 	 */
1747 	IFADDR_FOREACH(ifa, ifp) {
1748 		if (ifa->ifa_addr == NULL)
1749 			continue;	/* just for safety */
1750 		if (ifa->ifa_addr->sa_family != AF_INET6)
1751 			continue;
1752 		ifacount++;
1753 	}
1754 
1755 	ia->ia_addr = *sin6;
1756 
1757 	if (ifacount <= 1 &&
1758 	    (error = if_addr_init(ifp, &ia->ia_ifa, true)) != 0) {
1759 		splx(s);
1760 		return error;
1761 	}
1762 	splx(s);
1763 
1764 	ia->ia_ifa.ifa_metric = ifp->if_metric;
1765 
1766 	/* we could do in(6)_socktrim here, but just omit it at this moment. */
1767 
1768 	/*
1769 	 * Special case:
1770 	 * If the destination address is specified for a point-to-point
1771 	 * interface, install a route to the destination as an interface
1772 	 * direct route.
1773 	 */
1774 	plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
1775 	if (plen == 128 && ia->ia_dstaddr.sin6_family == AF_INET6) {
1776 		if ((error = rtinit(&ia->ia_ifa, RTM_ADD,
1777 				    RTF_UP | RTF_HOST)) != 0)
1778 			return error;
1779 		ia->ia_flags |= IFA_ROUTE;
1780 	}
1781 
1782 	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
1783 	if (newhost) {
1784 		/* set the rtrequest function to create llinfo */
1785 		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
1786 		in6_ifaddloop(&ia->ia_ifa);
1787 	}
1788 
1789 	if (ifp->if_flags & IFF_MULTICAST)
1790 		in6_restoremkludge(ia, ifp);
1791 
1792 	return error;
1793 }
1794 
1795 static struct ifaddr *
1796 bestifa(struct ifaddr *best_ifa, struct ifaddr *ifa)
1797 {
1798 	if (best_ifa == NULL || best_ifa->ifa_preference < ifa->ifa_preference)
1799 		return ifa;
1800 	return best_ifa;
1801 }
1802 
1803 /*
1804  * Find an IPv6 interface link-local address specific to an interface.
1805  */
1806 struct in6_ifaddr *
1807 in6ifa_ifpforlinklocal(const struct ifnet *ifp, const int ignoreflags)
1808 {
1809 	struct ifaddr *best_ifa = NULL, *ifa;
1810 
1811 	IFADDR_FOREACH(ifa, ifp) {
1812 		if (ifa->ifa_addr == NULL)
1813 			continue;	/* just for safety */
1814 		if (ifa->ifa_addr->sa_family != AF_INET6)
1815 			continue;
1816 		if (!IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa)))
1817 			continue;
1818 		if ((((struct in6_ifaddr *)ifa)->ia6_flags & ignoreflags) != 0)
1819 			continue;
1820 		best_ifa = bestifa(best_ifa, ifa);
1821 	}
1822 
1823 	return (struct in6_ifaddr *)best_ifa;
1824 }
1825 
1826 
1827 /*
1828  * find the internet address corresponding to a given interface and address.
1829  */
1830 struct in6_ifaddr *
1831 in6ifa_ifpwithaddr(const struct ifnet *ifp, const struct in6_addr *addr)
1832 {
1833 	struct ifaddr *best_ifa = NULL, *ifa;
1834 
1835 	IFADDR_FOREACH(ifa, ifp) {
1836 		if (ifa->ifa_addr == NULL)
1837 			continue;	/* just for safety */
1838 		if (ifa->ifa_addr->sa_family != AF_INET6)
1839 			continue;
1840 		if (!IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa)))
1841 			continue;
1842 		best_ifa = bestifa(best_ifa, ifa);
1843 	}
1844 
1845 	return (struct in6_ifaddr *)best_ifa;
1846 }
1847 
1848 static struct in6_ifaddr *
1849 bestia(struct in6_ifaddr *best_ia, struct in6_ifaddr *ia)
1850 {
1851 	if (best_ia == NULL ||
1852 	    best_ia->ia_ifa.ifa_preference < ia->ia_ifa.ifa_preference)
1853 		return ia;
1854 	return best_ia;
1855 }
1856 
1857 /*
1858  * find the internet address on a given interface corresponding to a neighbor's
1859  * address.
1860  */
1861 struct in6_ifaddr *
1862 in6ifa_ifplocaladdr(const struct ifnet *ifp, const struct in6_addr *addr)
1863 {
1864 	struct ifaddr *ifa;
1865 	struct in6_ifaddr *best_ia = NULL, *ia;
1866 
1867 	IFADDR_FOREACH(ifa, ifp) {
1868 		if (ifa->ifa_addr == NULL)
1869 			continue;	/* just for safety */
1870 		if (ifa->ifa_addr->sa_family != AF_INET6)
1871 			continue;
1872 		ia = (struct in6_ifaddr *)ifa;
1873 		if (!IN6_ARE_MASKED_ADDR_EQUAL(addr,
1874 				&ia->ia_addr.sin6_addr,
1875 				&ia->ia_prefixmask.sin6_addr))
1876 			continue;
1877 		best_ia = bestia(best_ia, ia);
1878 	}
1879 
1880 	return best_ia;
1881 }
1882 
1883 /*
1884  * Convert IP6 address to printable (loggable) representation.
1885  */
1886 static int ip6round = 0;
1887 char *
1888 ip6_sprintf(const struct in6_addr *addr)
1889 {
1890 	static char ip6buf[8][48];
1891 	int i;
1892 	char *bp;
1893 	char *cp;
1894 	const u_int16_t *a = (const u_int16_t *)addr;
1895 	const u_int8_t *d;
1896 	int dcolon = 0;
1897 
1898 	ip6round = (ip6round + 1) & 7;
1899 	cp = ip6buf[ip6round];
1900 
1901 	for (i = 0; i < 8; i++) {
1902 		if (dcolon == 1) {
1903 			if (*a == 0) {
1904 				if (i == 7)
1905 					*cp++ = ':';
1906 				a++;
1907 				continue;
1908 			} else
1909 				dcolon = 2;
1910 		}
1911 		if (*a == 0) {
1912 			if (dcolon == 0 && *(a + 1) == 0) {
1913 				if (i == 0)
1914 					*cp++ = ':';
1915 				*cp++ = ':';
1916 				dcolon = 1;
1917 			} else {
1918 				*cp++ = '0';
1919 				*cp++ = ':';
1920 			}
1921 			a++;
1922 			continue;
1923 		}
1924 		d = (const u_char *)a;
1925 		bp = cp;
1926 		*cp = hexdigits[*d >> 4];
1927 		if (*cp != '0')
1928 			cp++;
1929 		*cp = hexdigits[*d++ & 0xf];
1930 		if (cp != bp || *cp != '0')
1931 			cp++;
1932 		*cp = hexdigits[*d >> 4];
1933 		if (cp != bp || *cp != '0')
1934 			cp++;
1935 		*cp++ = hexdigits[*d & 0xf];
1936 		*cp++ = ':';
1937 		a++;
1938 	}
1939 	*--cp = 0;
1940 	return ip6buf[ip6round];
1941 }
1942 
1943 /*
1944  * Determine if an address is on a local network.
1945  */
1946 int
1947 in6_localaddr(const struct in6_addr *in6)
1948 {
1949 	struct in6_ifaddr *ia;
1950 
1951 	if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6))
1952 		return 1;
1953 
1954 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
1955 		if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
1956 					      &ia->ia_prefixmask.sin6_addr))
1957 			return 1;
1958 
1959 	return 0;
1960 }
1961 
1962 int
1963 in6_is_addr_deprecated(struct sockaddr_in6 *sa6)
1964 {
1965 	struct in6_ifaddr *ia;
1966 
1967 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1968 		if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
1969 		    &sa6->sin6_addr) &&
1970 #ifdef SCOPEDROUTING
1971 		    ia->ia_addr.sin6_scope_id == sa6->sin6_scope_id &&
1972 #endif
1973 		    (ia->ia6_flags & IN6_IFF_DEPRECATED) != 0)
1974 			return 1; /* true */
1975 
1976 		/* XXX: do we still have to go thru the rest of the list? */
1977 	}
1978 
1979 	return 0;		/* false */
1980 }
1981 
1982 /*
1983  * return length of part which dst and src are equal
1984  * hard coding...
1985  */
1986 int
1987 in6_matchlen(struct in6_addr *src, struct in6_addr *dst)
1988 {
1989 	int match = 0;
1990 	u_char *s = (u_char *)src, *d = (u_char *)dst;
1991 	u_char *lim = s + 16, r;
1992 
1993 	while (s < lim)
1994 		if ((r = (*d++ ^ *s++)) != 0) {
1995 			while (r < 128) {
1996 				match++;
1997 				r <<= 1;
1998 			}
1999 			break;
2000 		} else
2001 			match += NBBY;
2002 	return match;
2003 }
2004 
2005 /* XXX: to be scope conscious */
2006 int
2007 in6_are_prefix_equal(struct in6_addr *p1, struct in6_addr *p2, int len)
2008 {
2009 	int bytelen, bitlen;
2010 
2011 	/* sanity check */
2012 	if (len < 0 || len > 128) {
2013 		log(LOG_ERR, "in6_are_prefix_equal: invalid prefix length(%d)\n",
2014 		    len);
2015 		return 0;
2016 	}
2017 
2018 	bytelen = len / NBBY;
2019 	bitlen = len % NBBY;
2020 
2021 	if (memcmp(&p1->s6_addr, &p2->s6_addr, bytelen))
2022 		return 0;
2023 	if (bitlen != 0 &&
2024 	    p1->s6_addr[bytelen] >> (NBBY - bitlen) !=
2025 	    p2->s6_addr[bytelen] >> (NBBY - bitlen))
2026 		return 0;
2027 
2028 	return 1;
2029 }
2030 
2031 void
2032 in6_prefixlen2mask(struct in6_addr *maskp, int len)
2033 {
2034 	static const u_char maskarray[NBBY] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
2035 	int bytelen, bitlen, i;
2036 
2037 	/* sanity check */
2038 	if (len < 0 || len > 128) {
2039 		log(LOG_ERR, "in6_prefixlen2mask: invalid prefix length(%d)\n",
2040 		    len);
2041 		return;
2042 	}
2043 
2044 	memset(maskp, 0, sizeof(*maskp));
2045 	bytelen = len / NBBY;
2046 	bitlen = len % NBBY;
2047 	for (i = 0; i < bytelen; i++)
2048 		maskp->s6_addr[i] = 0xff;
2049 	if (bitlen)
2050 		maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
2051 }
2052 
2053 /*
2054  * return the best address out of the same scope. if no address was
2055  * found, return the first valid address from designated IF.
2056  */
2057 struct in6_ifaddr *
2058 in6_ifawithifp(struct ifnet *ifp, struct in6_addr *dst)
2059 {
2060 	int dst_scope =	in6_addrscope(dst), blen = -1, tlen;
2061 	struct ifaddr *ifa;
2062 	struct in6_ifaddr *best_ia = NULL, *ia;
2063 	struct in6_ifaddr *dep[2];	/* last-resort: deprecated */
2064 
2065 	dep[0] = dep[1] = NULL;
2066 
2067 	/*
2068 	 * We first look for addresses in the same scope.
2069 	 * If there is one, return it.
2070 	 * If two or more, return one which matches the dst longest.
2071 	 * If none, return one of global addresses assigned other ifs.
2072 	 */
2073 	IFADDR_FOREACH(ifa, ifp) {
2074 		if (ifa->ifa_addr->sa_family != AF_INET6)
2075 			continue;
2076 		ia = (struct in6_ifaddr *)ifa;
2077 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2078 			continue; /* XXX: is there any case to allow anycast? */
2079 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2080 			continue; /* don't use this interface */
2081 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2082 			continue;
2083 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2084 			if (ip6_use_deprecated)
2085 				dep[0] = ia;
2086 			continue;
2087 		}
2088 
2089 		if (dst_scope != in6_addrscope(IFA_IN6(ifa)))
2090 			continue;
2091 		/*
2092 		 * call in6_matchlen() as few as possible
2093 		 */
2094 		if (best_ia == NULL) {
2095 			best_ia = ia;
2096 			continue;
2097 		}
2098 		if (blen == -1)
2099 			blen = in6_matchlen(&best_ia->ia_addr.sin6_addr, dst);
2100 		tlen = in6_matchlen(IFA_IN6(ifa), dst);
2101 		if (tlen > blen) {
2102 			blen = tlen;
2103 			best_ia = ia;
2104 		} else if (tlen == blen)
2105 			best_ia = bestia(best_ia, ia);
2106 	}
2107 	if (best_ia != NULL)
2108 		return best_ia;
2109 
2110 	IFADDR_FOREACH(ifa, ifp) {
2111 		if (ifa->ifa_addr->sa_family != AF_INET6)
2112 			continue;
2113 		ia = (struct in6_ifaddr *)ifa;
2114 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2115 			continue; /* XXX: is there any case to allow anycast? */
2116 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2117 			continue; /* don't use this interface */
2118 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2119 			continue;
2120 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2121 			if (ip6_use_deprecated)
2122 				dep[1] = (struct in6_ifaddr *)ifa;
2123 			continue;
2124 		}
2125 
2126 		best_ia = bestia(best_ia, ia);
2127 	}
2128 	if (best_ia != NULL)
2129 		return best_ia;
2130 
2131 	/* use the last-resort values, that are, deprecated addresses */
2132 	if (dep[0])
2133 		return dep[0];
2134 	if (dep[1])
2135 		return dep[1];
2136 
2137 	return NULL;
2138 }
2139 
2140 /*
2141  * perform DAD when interface becomes IFF_UP.
2142  */
2143 void
2144 in6_if_up(struct ifnet *ifp)
2145 {
2146 	struct ifaddr *ifa;
2147 	struct in6_ifaddr *ia;
2148 
2149 	IFADDR_FOREACH(ifa, ifp) {
2150 		if (ifa->ifa_addr->sa_family != AF_INET6)
2151 			continue;
2152 		ia = (struct in6_ifaddr *)ifa;
2153 		if (ia->ia6_flags & IN6_IFF_TENTATIVE) {
2154 			/*
2155 			 * The TENTATIVE flag was likely set by hand
2156 			 * beforehand, implicitly indicating the need for DAD.
2157 			 * We may be able to skip the random delay in this
2158 			 * case, but we impose delays just in case.
2159 			 */
2160 			nd6_dad_start(ifa,
2161 			    cprng_fast32() %
2162 				(MAX_RTR_SOLICITATION_DELAY * hz));
2163 		}
2164 	}
2165 
2166 	/*
2167 	 * special cases, like 6to4, are handled in in6_ifattach
2168 	 */
2169 	in6_ifattach(ifp, NULL);
2170 }
2171 
2172 int
2173 in6if_do_dad(struct ifnet *ifp)
2174 {
2175 	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2176 		return 0;
2177 
2178 	switch (ifp->if_type) {
2179 	case IFT_FAITH:
2180 		/*
2181 		 * These interfaces do not have the IFF_LOOPBACK flag,
2182 		 * but loop packets back.  We do not have to do DAD on such
2183 		 * interfaces.  We should even omit it, because loop-backed
2184 		 * NS would confuse the DAD procedure.
2185 		 */
2186 		return 0;
2187 	default:
2188 		/*
2189 		 * Our DAD routine requires the interface up and running.
2190 		 * However, some interfaces can be up before the RUNNING
2191 		 * status.  Additionaly, users may try to assign addresses
2192 		 * before the interface becomes up (or running).
2193 		 * We simply skip DAD in such a case as a work around.
2194 		 * XXX: we should rather mark "tentative" on such addresses,
2195 		 * and do DAD after the interface becomes ready.
2196 		 */
2197 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
2198 		    (IFF_UP|IFF_RUNNING))
2199 			return 0;
2200 
2201 		return 1;
2202 	}
2203 }
2204 
2205 /*
2206  * Calculate max IPv6 MTU through all the interfaces and store it
2207  * to in6_maxmtu.
2208  */
2209 void
2210 in6_setmaxmtu(void)
2211 {
2212 	unsigned long maxmtu = 0;
2213 	struct ifnet *ifp;
2214 
2215 	TAILQ_FOREACH(ifp, &ifnet, if_list) {
2216 		/* this function can be called during ifnet initialization */
2217 		if (!ifp->if_afdata[AF_INET6])
2218 			continue;
2219 		if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
2220 		    IN6_LINKMTU(ifp) > maxmtu)
2221 			maxmtu = IN6_LINKMTU(ifp);
2222 	}
2223 	if (maxmtu)	     /* update only when maxmtu is positive */
2224 		in6_maxmtu = maxmtu;
2225 }
2226 
2227 /*
2228  * Provide the length of interface identifiers to be used for the link attached
2229  * to the given interface.  The length should be defined in "IPv6 over
2230  * xxx-link" document.  Note that address architecture might also define
2231  * the length for a particular set of address prefixes, regardless of the
2232  * link type.  As clarified in rfc2462bis, those two definitions should be
2233  * consistent, and those really are as of August 2004.
2234  */
2235 int
2236 in6_if2idlen(struct ifnet *ifp)
2237 {
2238 	switch (ifp->if_type) {
2239 	case IFT_ETHER:		/* RFC2464 */
2240 	case IFT_PROPVIRTUAL:	/* XXX: no RFC. treat it as ether */
2241 	case IFT_L2VLAN:	/* ditto */
2242 	case IFT_IEEE80211:	/* ditto */
2243 	case IFT_FDDI:		/* RFC2467 */
2244 	case IFT_ISO88025:	/* RFC2470 (IPv6 over Token Ring) */
2245 	case IFT_PPP:		/* RFC2472 */
2246 	case IFT_ARCNET:	/* RFC2497 */
2247 	case IFT_FRELAY:	/* RFC2590 */
2248 	case IFT_IEEE1394:	/* RFC3146 */
2249 	case IFT_GIF:		/* draft-ietf-v6ops-mech-v2-07 */
2250 	case IFT_LOOP:		/* XXX: is this really correct? */
2251 		return 64;
2252 	default:
2253 		/*
2254 		 * Unknown link type:
2255 		 * It might be controversial to use the today's common constant
2256 		 * of 64 for these cases unconditionally.  For full compliance,
2257 		 * we should return an error in this case.  On the other hand,
2258 		 * if we simply miss the standard for the link type or a new
2259 		 * standard is defined for a new link type, the IFID length
2260 		 * is very likely to be the common constant.  As a compromise,
2261 		 * we always use the constant, but make an explicit notice
2262 		 * indicating the "unknown" case.
2263 		 */
2264 		printf("in6_if2idlen: unknown link type (%d)\n", ifp->if_type);
2265 		return 64;
2266 	}
2267 }
2268 
2269 void *
2270 in6_domifattach(struct ifnet *ifp)
2271 {
2272 	struct in6_ifextra *ext;
2273 
2274 	ext = malloc(sizeof(*ext), M_IFADDR, M_WAITOK|M_ZERO);
2275 
2276 	ext->in6_ifstat = malloc(sizeof(struct in6_ifstat),
2277 	    M_IFADDR, M_WAITOK|M_ZERO);
2278 
2279 	ext->icmp6_ifstat = malloc(sizeof(struct icmp6_ifstat),
2280 	    M_IFADDR, M_WAITOK|M_ZERO);
2281 
2282 	ext->nd_ifinfo = nd6_ifattach(ifp);
2283 	ext->scope6_id = scope6_ifattach(ifp);
2284 	return ext;
2285 }
2286 
2287 void
2288 in6_domifdetach(struct ifnet *ifp, void *aux)
2289 {
2290 	struct in6_ifextra *ext = (struct in6_ifextra *)aux;
2291 
2292 	nd6_ifdetach(ext->nd_ifinfo);
2293 	free(ext->in6_ifstat, M_IFADDR);
2294 	free(ext->icmp6_ifstat, M_IFADDR);
2295 	scope6_ifdetach(ext->scope6_id);
2296 	free(ext, M_IFADDR);
2297 }
2298 
2299 /*
2300  * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
2301  * v4 mapped addr or v4 compat addr
2302  */
2303 void
2304 in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2305 {
2306 	memset(sin, 0, sizeof(*sin));
2307 	sin->sin_len = sizeof(struct sockaddr_in);
2308 	sin->sin_family = AF_INET;
2309 	sin->sin_port = sin6->sin6_port;
2310 	sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];
2311 }
2312 
2313 /* Convert sockaddr_in to sockaddr_in6 in v4 mapped addr format. */
2314 void
2315 in6_sin_2_v4mapsin6(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2316 {
2317 	memset(sin6, 0, sizeof(*sin6));
2318 	sin6->sin6_len = sizeof(struct sockaddr_in6);
2319 	sin6->sin6_family = AF_INET6;
2320 	sin6->sin6_port = sin->sin_port;
2321 	sin6->sin6_addr.s6_addr32[0] = 0;
2322 	sin6->sin6_addr.s6_addr32[1] = 0;
2323 	sin6->sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
2324 	sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;
2325 }
2326 
2327 /* Convert sockaddr_in6 into sockaddr_in. */
2328 void
2329 in6_sin6_2_sin_in_sock(struct sockaddr *nam)
2330 {
2331 	struct sockaddr_in *sin_p;
2332 	struct sockaddr_in6 sin6;
2333 
2334 	/*
2335 	 * Save original sockaddr_in6 addr and convert it
2336 	 * to sockaddr_in.
2337 	 */
2338 	sin6 = *(struct sockaddr_in6 *)nam;
2339 	sin_p = (struct sockaddr_in *)nam;
2340 	in6_sin6_2_sin(sin_p, &sin6);
2341 }
2342 
2343 /* Convert sockaddr_in into sockaddr_in6 in v4 mapped addr format. */
2344 void
2345 in6_sin_2_v4mapsin6_in_sock(struct sockaddr **nam)
2346 {
2347 	struct sockaddr_in *sin_p;
2348 	struct sockaddr_in6 *sin6_p;
2349 
2350 	sin6_p = malloc(sizeof(*sin6_p), M_SONAME, M_WAITOK);
2351 	sin_p = (struct sockaddr_in *)*nam;
2352 	in6_sin_2_v4mapsin6(sin_p, sin6_p);
2353 	free(*nam, M_SONAME);
2354 	*nam = (struct sockaddr *)sin6_p;
2355 }
2356