xref: /netbsd-src/sys/netinet6/in6.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: in6.c,v 1.174 2014/07/01 23:01:54 justin 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 1.174 2014/07/01 23:01:54 justin Exp $");
66 
67 #include "opt_inet.h"
68 #include "opt_compat_netbsd.h"
69 
70 #include <sys/param.h>
71 #include <sys/ioctl.h>
72 #include <sys/errno.h>
73 #include <sys/malloc.h>
74 #include <sys/socket.h>
75 #include <sys/socketvar.h>
76 #include <sys/sockio.h>
77 #include <sys/systm.h>
78 #include <sys/proc.h>
79 #include <sys/time.h>
80 #include <sys/kernel.h>
81 #include <sys/syslog.h>
82 #include <sys/kauth.h>
83 #include <sys/cprng.h>
84 
85 #include <net/if.h>
86 #include <net/if_types.h>
87 #include <net/route.h>
88 #include <net/if_dl.h>
89 #include <net/pfil.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 COMPAT_50
106 #include <compat/netinet6/in6_var.h>
107 #endif
108 
109 MALLOC_DEFINE(M_IP6OPT, "ip6_options", "IPv6 options");
110 
111 /* enable backward compatibility code for obsoleted ioctls */
112 #define COMPAT_IN6IFIOCTL
113 
114 #ifdef	IN6_DEBUG
115 #define	IN6_DPRINTF(__fmt, ...)	printf(__fmt, __VA_ARGS__)
116 #else
117 #define	IN6_DPRINTF(__fmt, ...)	do { } while (/*CONSTCOND*/0)
118 #endif /* IN6_DEBUG */
119 
120 /*
121  * Definitions of some constant IP6 addresses.
122  */
123 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
124 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
125 const struct in6_addr in6addr_nodelocal_allnodes =
126 	IN6ADDR_NODELOCAL_ALLNODES_INIT;
127 const struct in6_addr in6addr_linklocal_allnodes =
128 	IN6ADDR_LINKLOCAL_ALLNODES_INIT;
129 const struct in6_addr in6addr_linklocal_allrouters =
130 	IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
131 
132 const struct in6_addr in6mask0 = IN6MASK0;
133 const struct in6_addr in6mask32 = IN6MASK32;
134 const struct in6_addr in6mask64 = IN6MASK64;
135 const struct in6_addr in6mask96 = IN6MASK96;
136 const struct in6_addr in6mask128 = IN6MASK128;
137 
138 const struct sockaddr_in6 sa6_any = {sizeof(sa6_any), AF_INET6,
139 				     0, 0, IN6ADDR_ANY_INIT, 0};
140 
141 static int in6_lifaddr_ioctl(struct socket *, u_long, void *,
142 	struct ifnet *);
143 static int in6_ifinit(struct ifnet *, struct in6_ifaddr *,
144 	const struct sockaddr_in6 *, int);
145 static void in6_unlink_ifa(struct in6_ifaddr *, struct ifnet *);
146 
147 /*
148  * Subroutine for in6_ifaddloop() and in6_ifremloop().
149  * This routine does actual work.
150  */
151 static void
152 in6_ifloop_request(int cmd, struct ifaddr *ifa)
153 {
154 	struct sockaddr_in6 all1_sa;
155 	struct rtentry *nrt = NULL;
156 	int e;
157 
158 	sockaddr_in6_init(&all1_sa, &in6mask128, 0, 0, 0);
159 
160 	/*
161 	 * We specify the address itself as the gateway, and set the
162 	 * RTF_LLINFO flag, so that the corresponding host route would have
163 	 * the flag, and thus applications that assume traditional behavior
164 	 * would be happy.  Note that we assume the caller of the function
165 	 * (probably implicitly) set nd6_rtrequest() to ifa->ifa_rtrequest,
166 	 * which changes the outgoing interface to the loopback interface.
167 	 */
168 	e = rtrequest(cmd, ifa->ifa_addr, ifa->ifa_addr,
169 	    (struct sockaddr *)&all1_sa, RTF_UP|RTF_HOST|RTF_LLINFO, &nrt);
170 	if (e != 0) {
171 		log(LOG_ERR, "in6_ifloop_request: "
172 		    "%s operation failed for %s (errno=%d)\n",
173 		    cmd == RTM_ADD ? "ADD" : "DELETE",
174 		    ip6_sprintf(&((struct in6_ifaddr *)ifa)->ia_addr.sin6_addr),
175 		    e);
176 	}
177 
178 	/*
179 	 * Make sure rt_ifa be equal to IFA, the second argument of the
180 	 * function.
181 	 * We need this because when we refer to rt_ifa->ia6_flags in
182 	 * ip6_input, we assume that the rt_ifa points to the address instead
183 	 * of the loopback address.
184 	 */
185 	if (cmd == RTM_ADD && nrt && ifa != nrt->rt_ifa)
186 		rt_replace_ifa(nrt, ifa);
187 
188 	/*
189 	 * Report the addition/removal of the address to the routing socket
190 	 * unless the address is marked tentative, where it will be reported
191 	 * once DAD completes.
192 	 * XXX: since we called rtinit for a p2p interface with a destination,
193 	 *      we end up reporting twice in such a case.  Should we rather
194 	 *      omit the second report?
195 	 */
196 	if (nrt) {
197 		if (cmd != RTM_ADD ||
198 		    !(((struct in6_ifaddr *)ifa)->ia6_flags &IN6_IFF_TENTATIVE))
199 		{
200 #if 0
201 			struct in6_ifaddr *ia;
202 
203 			ia = (struct in6_ifaddr *)ifa;
204 			log(LOG_DEBUG,
205 			    "in6_ifloop_request: announced %s (%s %d)\n",
206 			    ip6_sprintf(&ia->ia_addr.sin6_addr),
207 			    cmd == RTM_ADD ? "RTM_ADD" : "RTM_DELETE",
208 			    ia->ia6_flags);
209 #endif
210 			rt_newaddrmsg(cmd, ifa, e, nrt);
211 		}
212 		if (cmd == RTM_DELETE) {
213 			if (nrt->rt_refcnt <= 0) {
214 				/* XXX: we should free the entry ourselves. */
215 				nrt->rt_refcnt++;
216 				rtfree(nrt);
217 			}
218 		} else {
219 			/* the cmd must be RTM_ADD here */
220 			nrt->rt_refcnt--;
221 		}
222 	}
223 }
224 
225 /*
226  * Add ownaddr as loopback rtentry.  We previously add the route only if
227  * necessary (ex. on a p2p link).  However, since we now manage addresses
228  * separately from prefixes, we should always add the route.  We can't
229  * rely on the cloning mechanism from the corresponding interface route
230  * any more.
231  */
232 void
233 in6_ifaddloop(struct ifaddr *ifa)
234 {
235 	struct rtentry *rt;
236 
237 	/* If there is no loopback entry, allocate one. */
238 	rt = rtalloc1(ifa->ifa_addr, 0);
239 	if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0 ||
240 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
241 		in6_ifloop_request(RTM_ADD, ifa);
242 	if (rt != NULL)
243 		rt->rt_refcnt--;
244 }
245 
246 /*
247  * Remove loopback rtentry of ownaddr generated by in6_ifaddloop(),
248  * if it exists.
249  */
250 void
251 in6_ifremloop(struct ifaddr *ifa)
252 {
253 	struct in6_ifaddr *alt_ia = NULL, *ia;
254 	struct rtentry *rt;
255 	int ia_count = 0;
256 
257 	/*
258 	 * Some of BSD variants do not remove cloned routes
259 	 * from an interface direct route, when removing the direct route
260 	 * (see comments in net/net_osdep.h).  Even for variants that do remove
261 	 * cloned routes, they could fail to remove the cloned routes when
262 	 * we handle multple addresses that share a common prefix.
263 	 * So, we should remove the route corresponding to the deleted address.
264 	 */
265 
266 	/*
267 	 * Delete the entry only if exactly one ifaddr matches the
268 	 * address, ifa->ifa_addr.
269 	 *
270 	 * If more than one ifaddr matches, replace the ifaddr in
271 	 * the routing table, rt_ifa, with a different ifaddr than
272 	 * the one we are purging, ifa.  It is important to do
273 	 * this, or else the routing table can accumulate dangling
274 	 * pointers rt->rt_ifa->ifa_ifp to destroyed interfaces,
275 	 * which will lead to crashes, later.  (More than one ifaddr
276 	 * can match if we assign the same address to multiple---probably
277 	 * p2p---interfaces.)
278 	 *
279 	 * XXX An old comment at this place said, "we should avoid
280 	 * XXX such a configuration [i.e., interfaces with the same
281 	 * XXX addressed assigned --ed.] in IPv6...".  I do not
282 	 * XXX agree, especially now that I have fixed the dangling
283 	 * XXX ifp-pointers bug.
284 	 */
285 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
286 		if (!IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ia->ia_addr.sin6_addr))
287 			continue;
288 		if (ia->ia_ifp != ifa->ifa_ifp)
289 			alt_ia = ia;
290 		if (++ia_count > 1 && alt_ia != NULL)
291 			break;
292 	}
293 
294 	if (ia_count == 0)
295 		return;
296 
297 	if ((rt = rtalloc1(ifa->ifa_addr, 0)) == NULL)
298 		return;
299 	rt->rt_refcnt--;
300 
301 	/*
302 	 * Before deleting, check if a corresponding loopbacked
303 	 * host route surely exists.  With this check, we can avoid
304 	 * deleting an interface direct route whose destination is
305 	 * the same as the address being removed.  This can happen
306 	 * when removing a subnet-router anycast address on an
307 	 * interface attached to a shared medium.
308 	 */
309 	if ((rt->rt_flags & RTF_HOST) == 0 ||
310 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
311 		return;
312 
313 	/* If we cannot replace the route's ifaddr with the equivalent
314 	 * ifaddr of another interface, I believe it is safest to
315 	 * delete the route.
316 	 */
317 	if (ia_count == 1 || alt_ia == NULL)
318 		in6_ifloop_request(RTM_DELETE, ifa);
319 	else
320 		rt_replace_ifa(rt, &alt_ia->ia_ifa);
321 }
322 
323 int
324 in6_mask2len(struct in6_addr *mask, u_char *lim0)
325 {
326 	int x = 0, y;
327 	u_char *lim = lim0, *p;
328 
329 	/* ignore the scope_id part */
330 	if (lim0 == NULL || lim0 - (u_char *)mask > sizeof(*mask))
331 		lim = (u_char *)mask + sizeof(*mask);
332 	for (p = (u_char *)mask; p < lim; x++, p++) {
333 		if (*p != 0xff)
334 			break;
335 	}
336 	y = 0;
337 	if (p < lim) {
338 		for (y = 0; y < NBBY; y++) {
339 			if ((*p & (0x80 >> y)) == 0)
340 				break;
341 		}
342 	}
343 
344 	/*
345 	 * when the limit pointer is given, do a stricter check on the
346 	 * remaining bits.
347 	 */
348 	if (p < lim) {
349 		if (y != 0 && (*p & (0x00ff >> y)) != 0)
350 			return -1;
351 		for (p = p + 1; p < lim; p++)
352 			if (*p != 0)
353 				return -1;
354 	}
355 
356 	return x * NBBY + y;
357 }
358 
359 #define ifa2ia6(ifa)	((struct in6_ifaddr *)(ifa))
360 #define ia62ifa(ia6)	(&((ia6)->ia_ifa))
361 
362 static int
363 in6_control1(struct socket *so, u_long cmd, void *data, struct ifnet *ifp)
364 {
365 	struct	in6_ifreq *ifr = (struct in6_ifreq *)data;
366 	struct	in6_ifaddr *ia = NULL;
367 	struct	in6_aliasreq *ifra = (struct in6_aliasreq *)data;
368 	struct sockaddr_in6 *sa6;
369 	int error;
370 
371 	switch (cmd) {
372 	/*
373 	 * XXX: Fix me, once we fix SIOCSIFADDR, SIOCIFDSTADDR, etc.
374 	 */
375 	case SIOCSIFADDR:
376 	case SIOCSIFDSTADDR:
377 	case SIOCSIFBRDADDR:
378 	case SIOCSIFNETMASK:
379 		return EOPNOTSUPP;
380 	case SIOCGETSGCNT_IN6:
381 	case SIOCGETMIFCNT_IN6:
382 		return mrt6_ioctl(cmd, data);
383 	case SIOCGIFADDRPREF:
384 	case SIOCSIFADDRPREF:
385 		if (ifp == NULL)
386 			return EINVAL;
387 		return ifaddrpref_ioctl(so, cmd, data, ifp);
388 	}
389 
390 	if (ifp == NULL)
391 		return EOPNOTSUPP;
392 
393 	switch (cmd) {
394 	case SIOCSNDFLUSH_IN6:
395 	case SIOCSPFXFLUSH_IN6:
396 	case SIOCSRTRFLUSH_IN6:
397 	case SIOCSDEFIFACE_IN6:
398 	case SIOCSIFINFO_FLAGS:
399 	case SIOCSIFINFO_IN6:
400 		/* Privileged. */
401 		/* FALLTHROUGH */
402 	case OSIOCGIFINFO_IN6:
403 	case SIOCGIFINFO_IN6:
404 	case SIOCGDRLST_IN6:
405 	case SIOCGPRLST_IN6:
406 	case SIOCGNBRINFO_IN6:
407 	case SIOCGDEFIFACE_IN6:
408 		return nd6_ioctl(cmd, data, ifp);
409 	}
410 
411 	switch (cmd) {
412 	case SIOCSIFPREFIX_IN6:
413 	case SIOCDIFPREFIX_IN6:
414 	case SIOCAIFPREFIX_IN6:
415 	case SIOCCIFPREFIX_IN6:
416 	case SIOCSGIFPREFIX_IN6:
417 	case SIOCGIFPREFIX_IN6:
418 		log(LOG_NOTICE,
419 		    "prefix ioctls are now invalidated. "
420 		    "please use ifconfig.\n");
421 		return EOPNOTSUPP;
422 	}
423 
424 	switch (cmd) {
425 	case SIOCALIFADDR:
426 	case SIOCDLIFADDR:
427 		/* Privileged. */
428 		/* FALLTHROUGH */
429 	case SIOCGLIFADDR:
430 		return in6_lifaddr_ioctl(so, cmd, data, ifp);
431 	}
432 
433 	/*
434 	 * Find address for this interface, if it exists.
435 	 *
436 	 * In netinet code, we have checked ifra_addr in SIOCSIF*ADDR operation
437 	 * only, and used the first interface address as the target of other
438 	 * operations (without checking ifra_addr).  This was because netinet
439 	 * code/API assumed at most 1 interface address per interface.
440 	 * Since IPv6 allows a node to assign multiple addresses
441 	 * on a single interface, we almost always look and check the
442 	 * presence of ifra_addr, and reject invalid ones here.
443 	 * It also decreases duplicated code among SIOC*_IN6 operations.
444 	 */
445 	switch (cmd) {
446 	case SIOCAIFADDR_IN6:
447 #ifdef OSIOCAIFADDR_IN6
448 	case OSIOCAIFADDR_IN6:
449 #endif
450 #ifdef OSIOCSIFPHYADDR_IN6
451 	case OSIOCSIFPHYADDR_IN6:
452 #endif
453 	case SIOCSIFPHYADDR_IN6:
454 		sa6 = &ifra->ifra_addr;
455 		break;
456 	case SIOCSIFADDR_IN6:
457 	case SIOCGIFADDR_IN6:
458 	case SIOCSIFDSTADDR_IN6:
459 	case SIOCSIFNETMASK_IN6:
460 	case SIOCGIFDSTADDR_IN6:
461 	case SIOCGIFNETMASK_IN6:
462 	case SIOCDIFADDR_IN6:
463 	case SIOCGIFPSRCADDR_IN6:
464 	case SIOCGIFPDSTADDR_IN6:
465 	case SIOCGIFAFLAG_IN6:
466 	case SIOCSNDFLUSH_IN6:
467 	case SIOCSPFXFLUSH_IN6:
468 	case SIOCSRTRFLUSH_IN6:
469 	case SIOCGIFALIFETIME_IN6:
470 #ifdef OSIOCGIFALIFETIME_IN6
471 	case OSIOCGIFALIFETIME_IN6:
472 #endif
473 	case SIOCGIFSTAT_IN6:
474 	case SIOCGIFSTAT_ICMP6:
475 		sa6 = &ifr->ifr_addr;
476 		break;
477 	default:
478 		sa6 = NULL;
479 		break;
480 	}
481 	if (sa6 && sa6->sin6_family == AF_INET6) {
482 		if (sa6->sin6_scope_id != 0)
483 			error = sa6_embedscope(sa6, 0);
484 		else
485 			error = in6_setscope(&sa6->sin6_addr, ifp, NULL);
486 		if (error != 0)
487 			return error;
488 		ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
489 	} else
490 		ia = NULL;
491 
492 	switch (cmd) {
493 	case SIOCSIFADDR_IN6:
494 	case SIOCSIFDSTADDR_IN6:
495 	case SIOCSIFNETMASK_IN6:
496 		/*
497 		 * Since IPv6 allows a node to assign multiple addresses
498 		 * on a single interface, SIOCSIFxxx ioctls are deprecated.
499 		 */
500 		return EINVAL;
501 
502 	case SIOCDIFADDR_IN6:
503 		/*
504 		 * for IPv4, we look for existing in_ifaddr here to allow
505 		 * "ifconfig if0 delete" to remove the first IPv4 address on
506 		 * the interface.  For IPv6, as the spec allows multiple
507 		 * interface address from the day one, we consider "remove the
508 		 * first one" semantics to be not preferable.
509 		 */
510 		if (ia == NULL)
511 			return EADDRNOTAVAIL;
512 		/* FALLTHROUGH */
513 #ifdef OSIOCAIFADDR_IN6
514 	case OSIOCAIFADDR_IN6:
515 #endif
516 	case SIOCAIFADDR_IN6:
517 		/*
518 		 * We always require users to specify a valid IPv6 address for
519 		 * the corresponding operation.
520 		 */
521 		if (ifra->ifra_addr.sin6_family != AF_INET6 ||
522 		    ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6))
523 			return EAFNOSUPPORT;
524 		/* Privileged. */
525 
526 		break;
527 
528 	case SIOCGIFADDR_IN6:
529 		/* This interface is basically deprecated. use SIOCGIFCONF. */
530 		/* FALLTHROUGH */
531 	case SIOCGIFAFLAG_IN6:
532 	case SIOCGIFNETMASK_IN6:
533 	case SIOCGIFDSTADDR_IN6:
534 	case SIOCGIFALIFETIME_IN6:
535 #ifdef OSIOCGIFALIFETIME_IN6
536 	case OSIOCGIFALIFETIME_IN6:
537 #endif
538 		/* must think again about its semantics */
539 		if (ia == NULL)
540 			return EADDRNOTAVAIL;
541 		break;
542 	}
543 
544 	switch (cmd) {
545 
546 	case SIOCGIFADDR_IN6:
547 		ifr->ifr_addr = ia->ia_addr;
548 		if ((error = sa6_recoverscope(&ifr->ifr_addr)) != 0)
549 			return error;
550 		break;
551 
552 	case SIOCGIFDSTADDR_IN6:
553 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
554 			return EINVAL;
555 		/*
556 		 * XXX: should we check if ifa_dstaddr is NULL and return
557 		 * an error?
558 		 */
559 		ifr->ifr_dstaddr = ia->ia_dstaddr;
560 		if ((error = sa6_recoverscope(&ifr->ifr_dstaddr)) != 0)
561 			return error;
562 		break;
563 
564 	case SIOCGIFNETMASK_IN6:
565 		ifr->ifr_addr = ia->ia_prefixmask;
566 		break;
567 
568 	case SIOCGIFAFLAG_IN6:
569 		ifr->ifr_ifru.ifru_flags6 = ia->ia6_flags;
570 		break;
571 
572 	case SIOCGIFSTAT_IN6:
573 		if (ifp == NULL)
574 			return EINVAL;
575 		memset(&ifr->ifr_ifru.ifru_stat, 0,
576 		    sizeof(ifr->ifr_ifru.ifru_stat));
577 		ifr->ifr_ifru.ifru_stat =
578 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->in6_ifstat;
579 		break;
580 
581 	case SIOCGIFSTAT_ICMP6:
582 		if (ifp == NULL)
583 			return EINVAL;
584 		memset(&ifr->ifr_ifru.ifru_icmp6stat, 0,
585 		    sizeof(ifr->ifr_ifru.ifru_icmp6stat));
586 		ifr->ifr_ifru.ifru_icmp6stat =
587 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->icmp6_ifstat;
588 		break;
589 
590 #ifdef OSIOCGIFALIFETIME_IN6
591 	case OSIOCGIFALIFETIME_IN6:
592 #endif
593 	case SIOCGIFALIFETIME_IN6:
594 		ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
595 		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
596 			time_t maxexpire;
597 			struct in6_addrlifetime *retlt =
598 			    &ifr->ifr_ifru.ifru_lifetime;
599 
600 			/*
601 			 * XXX: adjust expiration time assuming time_t is
602 			 * signed.
603 			 */
604 			maxexpire = ((time_t)~0) &
605 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
606 			if (ia->ia6_lifetime.ia6t_vltime <
607 			    maxexpire - ia->ia6_updatetime) {
608 				retlt->ia6t_expire = ia->ia6_updatetime +
609 				    ia->ia6_lifetime.ia6t_vltime;
610 			} else
611 				retlt->ia6t_expire = maxexpire;
612 		}
613 		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
614 			time_t maxexpire;
615 			struct in6_addrlifetime *retlt =
616 			    &ifr->ifr_ifru.ifru_lifetime;
617 
618 			/*
619 			 * XXX: adjust expiration time assuming time_t is
620 			 * signed.
621 			 */
622 			maxexpire = ((time_t)~0) &
623 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
624 			if (ia->ia6_lifetime.ia6t_pltime <
625 			    maxexpire - ia->ia6_updatetime) {
626 				retlt->ia6t_preferred = ia->ia6_updatetime +
627 				    ia->ia6_lifetime.ia6t_pltime;
628 			} else
629 				retlt->ia6t_preferred = maxexpire;
630 		}
631 #ifdef OSIOCFIFALIFETIME_IN6
632 		if (cmd == OSIOCFIFALIFETIME_IN6)
633 			in6_addrlifetime_to_in6_addrlifetime50(
634 			    &ifr->ifru.ifru_lifetime);
635 #endif
636 		break;
637 
638 #ifdef OSIOCAIFADDR_IN6
639 	case OSIOCAIFADDR_IN6:
640 		in6_aliasreq50_to_in6_aliasreq(ifra);
641 		/*FALLTHROUGH*/
642 #endif
643 	case SIOCAIFADDR_IN6:
644 	{
645 		int i;
646 		struct nd_prefixctl pr0;
647 		struct nd_prefix *pr;
648 
649 		/* reject read-only flags */
650 		if ((ifra->ifra_flags & IN6_IFF_DUPLICATED) != 0 ||
651 		    (ifra->ifra_flags & IN6_IFF_DETACHED) != 0 ||
652 		    (ifra->ifra_flags & IN6_IFF_NODAD) != 0 ||
653 		    (ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0) {
654 			return EINVAL;
655 		}
656 		/*
657 		 * first, make or update the interface address structure,
658 		 * and link it to the list.
659 		 */
660 		if ((error = in6_update_ifa(ifp, ifra, ia, 0)) != 0)
661 			return error;
662 		if ((ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr))
663 		    == NULL) {
664 		    	/*
665 			 * this can happen when the user specify the 0 valid
666 			 * lifetime.
667 			 */
668 			break;
669 		}
670 
671 		/*
672 		 * then, make the prefix on-link on the interface.
673 		 * XXX: we'd rather create the prefix before the address, but
674 		 * we need at least one address to install the corresponding
675 		 * interface route, so we configure the address first.
676 		 */
677 
678 		/*
679 		 * convert mask to prefix length (prefixmask has already
680 		 * been validated in in6_update_ifa().
681 		 */
682 		memset(&pr0, 0, sizeof(pr0));
683 		pr0.ndpr_ifp = ifp;
684 		pr0.ndpr_plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
685 		    NULL);
686 		if (pr0.ndpr_plen == 128) {
687 			break;	/* we don't need to install a host route. */
688 		}
689 		pr0.ndpr_prefix = ifra->ifra_addr;
690 		/* apply the mask for safety. */
691 		for (i = 0; i < 4; i++) {
692 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
693 			    ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
694 		}
695 		/*
696 		 * XXX: since we don't have an API to set prefix (not address)
697 		 * lifetimes, we just use the same lifetimes as addresses.
698 		 * The (temporarily) installed lifetimes can be overridden by
699 		 * later advertised RAs (when accept_rtadv is non 0), which is
700 		 * an intended behavior.
701 		 */
702 		pr0.ndpr_raf_onlink = 1; /* should be configurable? */
703 		pr0.ndpr_raf_auto =
704 		    ((ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0);
705 		pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
706 		pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;
707 
708 		/* add the prefix if not yet. */
709 		if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
710 			/*
711 			 * nd6_prelist_add will install the corresponding
712 			 * interface route.
713 			 */
714 			if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
715 				return error;
716 			if (pr == NULL) {
717 				log(LOG_ERR, "nd6_prelist_add succeeded but "
718 				    "no prefix\n");
719 				return EINVAL; /* XXX panic here? */
720 			}
721 		}
722 
723 		/* relate the address to the prefix */
724 		if (ia->ia6_ndpr == NULL) {
725 			ia->ia6_ndpr = pr;
726 			pr->ndpr_refcnt++;
727 
728 			/*
729 			 * If this is the first autoconf address from the
730 			 * prefix, create a temporary address as well
731 			 * (when required).
732 			 */
733 			if ((ia->ia6_flags & IN6_IFF_AUTOCONF) &&
734 			    ip6_use_tempaddr && pr->ndpr_refcnt == 1) {
735 				int e;
736 				if ((e = in6_tmpifadd(ia, 1, 0)) != 0) {
737 					log(LOG_NOTICE, "in6_control: failed "
738 					    "to create a temporary address, "
739 					    "errno=%d\n", e);
740 				}
741 			}
742 		}
743 
744 		/*
745 		 * this might affect the status of autoconfigured addresses,
746 		 * that is, this address might make other addresses detached.
747 		 */
748 		pfxlist_onlink_check();
749 
750 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCAIFADDR_IN6,
751 		    ifp, PFIL_IFADDR);
752 		break;
753 	}
754 
755 	case SIOCDIFADDR_IN6:
756 	{
757 		struct nd_prefix *pr;
758 
759 		/*
760 		 * If the address being deleted is the only one that owns
761 		 * the corresponding prefix, expire the prefix as well.
762 		 * XXX: theoretically, we don't have to worry about such
763 		 * relationship, since we separate the address management
764 		 * and the prefix management.  We do this, however, to provide
765 		 * as much backward compatibility as possible in terms of
766 		 * the ioctl operation.
767 		 * Note that in6_purgeaddr() will decrement ndpr_refcnt.
768 		 */
769 		pr = ia->ia6_ndpr;
770 		in6_purgeaddr(&ia->ia_ifa);
771 		if (pr && pr->ndpr_refcnt == 0)
772 			prelist_remove(pr);
773 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCDIFADDR_IN6,
774 		    ifp, PFIL_IFADDR);
775 		break;
776 	}
777 
778 	default:
779 		return ENOTTY;
780 	}
781 
782 	return 0;
783 }
784 
785 int
786 in6_control(struct socket *so, u_long cmd, void *data, struct ifnet *ifp)
787 {
788 	int error, s;
789 
790 	switch (cmd) {
791 	case SIOCSNDFLUSH_IN6:
792 	case SIOCSPFXFLUSH_IN6:
793 	case SIOCSRTRFLUSH_IN6:
794 	case SIOCSDEFIFACE_IN6:
795 	case SIOCSIFINFO_FLAGS:
796 	case SIOCSIFINFO_IN6:
797 
798 	case SIOCALIFADDR:
799 	case SIOCDLIFADDR:
800 
801 	case SIOCDIFADDR_IN6:
802 #ifdef OSIOCAIFADDR_IN6
803 	case OSIOCAIFADDR_IN6:
804 #endif
805 	case SIOCAIFADDR_IN6:
806 		if (kauth_authorize_network(curlwp->l_cred,
807 		    KAUTH_NETWORK_SOCKET,
808 		    KAUTH_REQ_NETWORK_SOCKET_SETPRIV,
809 		    so, NULL, NULL))
810 			return EPERM;
811 		break;
812 	}
813 
814 	s = splnet();
815 	error = in6_control1(so , cmd, data, ifp);
816 	splx(s);
817 	return error;
818 }
819 
820 /*
821  * Update parameters of an IPv6 interface address.
822  * If necessary, a new entry is created and linked into address chains.
823  * This function is separated from in6_control().
824  * XXX: should this be performed under splnet()?
825  */
826 static int
827 in6_update_ifa1(struct ifnet *ifp, struct in6_aliasreq *ifra,
828     struct in6_ifaddr *ia, int flags)
829 {
830 	int error = 0, hostIsNew = 0, plen = -1;
831 	struct in6_ifaddr *oia;
832 	struct sockaddr_in6 dst6;
833 	struct in6_addrlifetime *lt;
834 	struct in6_multi_mship *imm;
835 	struct in6_multi *in6m_sol;
836 	struct rtentry *rt;
837 	int dad_delay;
838 
839 	in6m_sol = NULL;
840 
841 	/* Validate parameters */
842 	if (ifp == NULL || ifra == NULL) /* this maybe redundant */
843 		return EINVAL;
844 
845 	/*
846 	 * The destination address for a p2p link must have a family
847 	 * of AF_UNSPEC or AF_INET6.
848 	 */
849 	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
850 	    ifra->ifra_dstaddr.sin6_family != AF_INET6 &&
851 	    ifra->ifra_dstaddr.sin6_family != AF_UNSPEC)
852 		return EAFNOSUPPORT;
853 	/*
854 	 * validate ifra_prefixmask.  don't check sin6_family, netmask
855 	 * does not carry fields other than sin6_len.
856 	 */
857 	if (ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6))
858 		return EINVAL;
859 	/*
860 	 * Because the IPv6 address architecture is classless, we require
861 	 * users to specify a (non 0) prefix length (mask) for a new address.
862 	 * We also require the prefix (when specified) mask is valid, and thus
863 	 * reject a non-consecutive mask.
864 	 */
865 	if (ia == NULL && ifra->ifra_prefixmask.sin6_len == 0)
866 		return EINVAL;
867 	if (ifra->ifra_prefixmask.sin6_len != 0) {
868 		plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
869 		    (u_char *)&ifra->ifra_prefixmask +
870 		    ifra->ifra_prefixmask.sin6_len);
871 		if (plen <= 0)
872 			return EINVAL;
873 	} else {
874 		/*
875 		 * In this case, ia must not be NULL.  We just use its prefix
876 		 * length.
877 		 */
878 		plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
879 	}
880 	/*
881 	 * If the destination address on a p2p interface is specified,
882 	 * and the address is a scoped one, validate/set the scope
883 	 * zone identifier.
884 	 */
885 	dst6 = ifra->ifra_dstaddr;
886 	if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) != 0 &&
887 	    (dst6.sin6_family == AF_INET6)) {
888 		struct in6_addr in6_tmp;
889 		u_int32_t zoneid;
890 
891 		in6_tmp = dst6.sin6_addr;
892 		if (in6_setscope(&in6_tmp, ifp, &zoneid))
893 			return EINVAL; /* XXX: should be impossible */
894 
895 		if (dst6.sin6_scope_id != 0) {
896 			if (dst6.sin6_scope_id != zoneid)
897 				return EINVAL;
898 		} else		/* user omit to specify the ID. */
899 			dst6.sin6_scope_id = zoneid;
900 
901 		/* convert into the internal form */
902 		if (sa6_embedscope(&dst6, 0))
903 			return EINVAL; /* XXX: should be impossible */
904 	}
905 	/*
906 	 * The destination address can be specified only for a p2p or a
907 	 * loopback interface.  If specified, the corresponding prefix length
908 	 * must be 128.
909 	 */
910 	if (ifra->ifra_dstaddr.sin6_family == AF_INET6) {
911 #ifdef FORCE_P2PPLEN
912 		int i;
913 #endif
914 
915 		if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) == 0) {
916 			/* XXX: noisy message */
917 			nd6log((LOG_INFO, "in6_update_ifa: a destination can "
918 			    "be specified for a p2p or a loopback IF only\n"));
919 			return EINVAL;
920 		}
921 		if (plen != 128) {
922 			nd6log((LOG_INFO, "in6_update_ifa: prefixlen should "
923 			    "be 128 when dstaddr is specified\n"));
924 #ifdef FORCE_P2PPLEN
925 			/*
926 			 * To be compatible with old configurations,
927 			 * such as ifconfig gif0 inet6 2001::1 2001::2
928 			 * prefixlen 126, we override the specified
929 			 * prefixmask as if the prefix length was 128.
930 			 */
931 			ifra->ifra_prefixmask.sin6_len =
932 			    sizeof(struct sockaddr_in6);
933 			for (i = 0; i < 4; i++)
934 				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i] =
935 				    0xffffffff;
936 			plen = 128;
937 #else
938 			return EINVAL;
939 #endif
940 		}
941 	}
942 	/* lifetime consistency check */
943 	lt = &ifra->ifra_lifetime;
944 	if (lt->ia6t_pltime > lt->ia6t_vltime)
945 		return EINVAL;
946 	if (lt->ia6t_vltime == 0) {
947 		/*
948 		 * the following log might be noisy, but this is a typical
949 		 * configuration mistake or a tool's bug.
950 		 */
951 		nd6log((LOG_INFO,
952 		    "in6_update_ifa: valid lifetime is 0 for %s\n",
953 		    ip6_sprintf(&ifra->ifra_addr.sin6_addr)));
954 
955 		if (ia == NULL)
956 			return 0; /* there's nothing to do */
957 	}
958 
959 	/*
960 	 * If this is a new address, allocate a new ifaddr and link it
961 	 * into chains.
962 	 */
963 	if (ia == NULL) {
964 		hostIsNew = 1;
965 		/*
966 		 * When in6_update_ifa() is called in a process of a received
967 		 * RA, it is called under an interrupt context.  So, we should
968 		 * call malloc with M_NOWAIT.
969 		 */
970 		ia = (struct in6_ifaddr *) malloc(sizeof(*ia), M_IFADDR,
971 		    M_NOWAIT);
972 		if (ia == NULL)
973 			return ENOBUFS;
974 		memset(ia, 0, sizeof(*ia));
975 		LIST_INIT(&ia->ia6_memberships);
976 		/* Initialize the address and masks, and put time stamp */
977 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
978 		ia->ia_addr.sin6_family = AF_INET6;
979 		ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
980 		ia->ia6_createtime = time_second;
981 		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
982 			/*
983 			 * XXX: some functions expect that ifa_dstaddr is not
984 			 * NULL for p2p interfaces.
985 			 */
986 			ia->ia_ifa.ifa_dstaddr =
987 			    (struct sockaddr *)&ia->ia_dstaddr;
988 		} else {
989 			ia->ia_ifa.ifa_dstaddr = NULL;
990 		}
991 		ia->ia_ifa.ifa_netmask =
992 		    (struct sockaddr *)&ia->ia_prefixmask;
993 
994 		ia->ia_ifp = ifp;
995 		if ((oia = in6_ifaddr) != NULL) {
996 			for ( ; oia->ia_next; oia = oia->ia_next)
997 				continue;
998 			oia->ia_next = ia;
999 		} else
1000 			in6_ifaddr = ia;
1001 		/* gain a refcnt for the link from in6_ifaddr */
1002 		IFAREF(&ia->ia_ifa);
1003 
1004 		ifa_insert(ifp, &ia->ia_ifa);
1005 	}
1006 
1007 	/* update timestamp */
1008 	ia->ia6_updatetime = time_second;
1009 
1010 	/* set prefix mask */
1011 	if (ifra->ifra_prefixmask.sin6_len) {
1012 		/*
1013 		 * We prohibit changing the prefix length of an existing
1014 		 * address, because
1015 		 * + such an operation should be rare in IPv6, and
1016 		 * + the operation would confuse prefix management.
1017 		 */
1018 		if (ia->ia_prefixmask.sin6_len &&
1019 		    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL) != plen) {
1020 			nd6log((LOG_INFO, "in6_update_ifa: the prefix length of an"
1021 			    " existing (%s) address should not be changed\n",
1022 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1023 			error = EINVAL;
1024 			goto unlink;
1025 		}
1026 		ia->ia_prefixmask = ifra->ifra_prefixmask;
1027 	}
1028 
1029 	/*
1030 	 * If a new destination address is specified, scrub the old one and
1031 	 * install the new destination.  Note that the interface must be
1032 	 * p2p or loopback (see the check above.)
1033 	 */
1034 	if (dst6.sin6_family == AF_INET6 &&
1035 	    !IN6_ARE_ADDR_EQUAL(&dst6.sin6_addr, &ia->ia_dstaddr.sin6_addr)) {
1036 		if ((ia->ia_flags & IFA_ROUTE) != 0 &&
1037 		    rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST) != 0) {
1038 			nd6log((LOG_ERR, "in6_update_ifa: failed to remove "
1039 			    "a route to the old destination: %s\n",
1040 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1041 			/* proceed anyway... */
1042 		} else
1043 			ia->ia_flags &= ~IFA_ROUTE;
1044 		ia->ia_dstaddr = dst6;
1045 	}
1046 
1047 	/*
1048 	 * Set lifetimes.  We do not refer to ia6t_expire and ia6t_preferred
1049 	 * to see if the address is deprecated or invalidated, but initialize
1050 	 * these members for applications.
1051 	 */
1052 	ia->ia6_lifetime = ifra->ifra_lifetime;
1053 	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
1054 		ia->ia6_lifetime.ia6t_expire =
1055 		    time_second + ia->ia6_lifetime.ia6t_vltime;
1056 	} else
1057 		ia->ia6_lifetime.ia6t_expire = 0;
1058 	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
1059 		ia->ia6_lifetime.ia6t_preferred =
1060 		    time_second + ia->ia6_lifetime.ia6t_pltime;
1061 	} else
1062 		ia->ia6_lifetime.ia6t_preferred = 0;
1063 
1064 	/*
1065 	 * configure address flags.
1066 	 */
1067 	ia->ia6_flags = ifra->ifra_flags;
1068 
1069 	/*
1070 	 * Make the address tentative before joining multicast addresses,
1071 	 * so that corresponding MLD responses would not have a tentative
1072 	 * source address.
1073 	 */
1074 	ia->ia6_flags &= ~IN6_IFF_DUPLICATED;	/* safety */
1075 	if (ifp->if_link_state == LINK_STATE_DOWN) {
1076 		ia->ia6_flags |= IN6_IFF_DETACHED;
1077 		ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1078 	} else if (hostIsNew && in6if_do_dad(ifp))
1079 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
1080 
1081 	/*
1082 	 * backward compatibility - if IN6_IFF_DEPRECATED is set from the
1083 	 * userland, make it deprecated.
1084 	 */
1085 	if ((ifra->ifra_flags & IN6_IFF_DEPRECATED) != 0) {
1086 		ia->ia6_lifetime.ia6t_pltime = 0;
1087 		ia->ia6_lifetime.ia6t_preferred = time_second;
1088 	}
1089 
1090 	/* reset the interface and routing table appropriately. */
1091 	if ((error = in6_ifinit(ifp, ia, &ifra->ifra_addr, hostIsNew)) != 0)
1092 		goto unlink;
1093 	/*
1094 	 * We are done if we have simply modified an existing address.
1095 	 */
1096 	if (!hostIsNew)
1097 		return error;
1098 
1099 	/*
1100 	 * Beyond this point, we should call in6_purgeaddr upon an error,
1101 	 * not just go to unlink.
1102 	 */
1103 
1104 	/* join necessary multicast groups */
1105 	if ((ifp->if_flags & IFF_MULTICAST) != 0) {
1106 		struct sockaddr_in6 mltaddr, mltmask;
1107 		struct in6_addr llsol;
1108 
1109 		/* join solicited multicast addr for new host id */
1110 		memset(&llsol, 0, sizeof(struct in6_addr));
1111 		llsol.s6_addr16[0] = htons(0xff02);
1112 		llsol.s6_addr32[1] = 0;
1113 		llsol.s6_addr32[2] = htonl(1);
1114 		llsol.s6_addr32[3] = ifra->ifra_addr.sin6_addr.s6_addr32[3];
1115 		llsol.s6_addr8[12] = 0xff;
1116 		if ((error = in6_setscope(&llsol, ifp, NULL)) != 0) {
1117 			/* XXX: should not happen */
1118 			log(LOG_ERR, "in6_update_ifa: "
1119 			    "in6_setscope failed\n");
1120 			goto cleanup;
1121 		}
1122 		dad_delay = 0;
1123 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1124 			/*
1125 			 * We need a random delay for DAD on the address
1126 			 * being configured.  It also means delaying
1127 			 * transmission of the corresponding MLD report to
1128 			 * avoid report collision.
1129 			 * [draft-ietf-ipv6-rfc2462bis-02.txt]
1130 			 */
1131 			dad_delay = cprng_fast32() %
1132 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1133 		}
1134 
1135 #define	MLTMASK_LEN  4	/* mltmask's masklen (=32bit=4octet) */
1136 		/* join solicited multicast addr for new host id */
1137 		imm = in6_joingroup(ifp, &llsol, &error, dad_delay);
1138 		if (!imm) {
1139 			nd6log((LOG_ERR,
1140 			    "in6_update_ifa: addmulti "
1141 			    "failed for %s on %s (errno=%d)\n",
1142 			    ip6_sprintf(&llsol), if_name(ifp), error));
1143 			goto cleanup;
1144 		}
1145 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1146 		in6m_sol = imm->i6mm_maddr;
1147 
1148 		sockaddr_in6_init(&mltmask, &in6mask32, 0, 0, 0);
1149 
1150 		/*
1151 		 * join link-local all-nodes address
1152 		 */
1153 		sockaddr_in6_init(&mltaddr, &in6addr_linklocal_allnodes,
1154 		    0, 0, 0);
1155 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1156 			goto cleanup; /* XXX: should not fail */
1157 
1158 		/*
1159 		 * XXX: do we really need this automatic routes?
1160 		 * We should probably reconsider this stuff.  Most applications
1161 		 * actually do not need the routes, since they usually specify
1162 		 * the outgoing interface.
1163 		 */
1164 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1165 		if (rt) {
1166 			if (memcmp(&mltaddr.sin6_addr,
1167 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1168 			    MLTMASK_LEN)) {
1169 				rtfree(rt);
1170 				rt = NULL;
1171 			} else if (rt->rt_ifp != ifp) {
1172 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1173 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1174 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1175 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1176 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1177 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1178 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1179 				rt_replace_ifa(rt, &ia->ia_ifa);
1180 				rt->rt_ifp = ifp;
1181 			}
1182 		}
1183 		if (!rt) {
1184 			struct rt_addrinfo info;
1185 
1186 			memset(&info, 0, sizeof(info));
1187 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1188 			info.rti_info[RTAX_GATEWAY] =
1189 			    (struct sockaddr *)&ia->ia_addr;
1190 			info.rti_info[RTAX_NETMASK] =
1191 			    (struct sockaddr *)&mltmask;
1192 			info.rti_info[RTAX_IFA] =
1193 			    (struct sockaddr *)&ia->ia_addr;
1194 			/* XXX: we need RTF_CLONING to fake nd6_rtrequest */
1195 			info.rti_flags = RTF_UP | RTF_CLONING;
1196 			error = rtrequest1(RTM_ADD, &info, NULL);
1197 			if (error)
1198 				goto cleanup;
1199 		} else {
1200 			rtfree(rt);
1201 		}
1202 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1203 		if (!imm) {
1204 			nd6log((LOG_WARNING,
1205 			    "in6_update_ifa: addmulti failed for "
1206 			    "%s on %s (errno=%d)\n",
1207 			    ip6_sprintf(&mltaddr.sin6_addr),
1208 			    if_name(ifp), error));
1209 			goto cleanup;
1210 		}
1211 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1212 
1213 		/*
1214 		 * join node information group address
1215 		 */
1216 		dad_delay = 0;
1217 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1218 			/*
1219 			 * The spec doesn't say anything about delay for this
1220 			 * group, but the same logic should apply.
1221 			 */
1222 			dad_delay = cprng_fast32() %
1223 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1224 		}
1225 		if (in6_nigroup(ifp, hostname, hostnamelen, &mltaddr) != 0)
1226 			;
1227 		else if ((imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error,
1228 		          dad_delay)) == NULL) { /* XXX jinmei */
1229 			nd6log((LOG_WARNING, "in6_update_ifa: "
1230 			    "addmulti failed for %s on %s (errno=%d)\n",
1231 			    ip6_sprintf(&mltaddr.sin6_addr),
1232 			    if_name(ifp), error));
1233 			/* XXX not very fatal, go on... */
1234 		} else {
1235 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1236 		}
1237 
1238 
1239 		/*
1240 		 * join interface-local all-nodes address.
1241 		 * (ff01::1%ifN, and ff01::%ifN/32)
1242 		 */
1243 		mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
1244 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1245 			goto cleanup; /* XXX: should not fail */
1246 
1247 		/* XXX: again, do we really need the route? */
1248 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1249 		if (rt) {
1250 			/* 32bit came from "mltmask" */
1251 			if (memcmp(&mltaddr.sin6_addr,
1252 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1253 			    32 / NBBY)) {
1254 				rtfree(rt);
1255 				rt = NULL;
1256 			} else if (rt->rt_ifp != ifp) {
1257 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1258 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1259 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1260 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1261 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1262 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1263 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1264 				rt_replace_ifa(rt, &ia->ia_ifa);
1265 				rt->rt_ifp = ifp;
1266 			}
1267 		}
1268 		if (!rt) {
1269 			struct rt_addrinfo info;
1270 
1271 			memset(&info, 0, sizeof(info));
1272 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1273 			info.rti_info[RTAX_GATEWAY] =
1274 			    (struct sockaddr *)&ia->ia_addr;
1275 			info.rti_info[RTAX_NETMASK] =
1276 			    (struct sockaddr *)&mltmask;
1277 			info.rti_info[RTAX_IFA] =
1278 			    (struct sockaddr *)&ia->ia_addr;
1279 			info.rti_flags = RTF_UP | RTF_CLONING;
1280 			error = rtrequest1(RTM_ADD, &info, NULL);
1281 			if (error)
1282 				goto cleanup;
1283 #undef	MLTMASK_LEN
1284 		} else {
1285 			rtfree(rt);
1286 		}
1287 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1288 		if (!imm) {
1289 			nd6log((LOG_WARNING, "in6_update_ifa: "
1290 			    "addmulti failed for %s on %s (errno=%d)\n",
1291 			    ip6_sprintf(&mltaddr.sin6_addr),
1292 			    if_name(ifp), error));
1293 			goto cleanup;
1294 		} else {
1295 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1296 		}
1297 	}
1298 
1299 	/*
1300 	 * Perform DAD, if needed.
1301 	 * XXX It may be of use, if we can administratively
1302 	 * disable DAD.
1303 	 */
1304 	if (hostIsNew && in6if_do_dad(ifp) &&
1305 	    ((ifra->ifra_flags & IN6_IFF_NODAD) == 0) &&
1306 	    (ia->ia6_flags & IN6_IFF_TENTATIVE))
1307 	{
1308 		int mindelay, maxdelay;
1309 
1310 		dad_delay = 0;
1311 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1312 			/*
1313 			 * We need to impose a delay before sending an NS
1314 			 * for DAD.  Check if we also needed a delay for the
1315 			 * corresponding MLD message.  If we did, the delay
1316 			 * should be larger than the MLD delay (this could be
1317 			 * relaxed a bit, but this simple logic is at least
1318 			 * safe).
1319 			 */
1320 			mindelay = 0;
1321 			if (in6m_sol != NULL &&
1322 			    in6m_sol->in6m_state == MLD_REPORTPENDING) {
1323 				mindelay = in6m_sol->in6m_timer;
1324 			}
1325 			maxdelay = MAX_RTR_SOLICITATION_DELAY * hz;
1326 			if (maxdelay - mindelay == 0)
1327 				dad_delay = 0;
1328 			else {
1329 				dad_delay =
1330 				    (cprng_fast32() % (maxdelay - mindelay)) +
1331 				    mindelay;
1332 			}
1333 		}
1334 		/* +1 ensures callout is always used */
1335 		nd6_dad_start(&ia->ia_ifa, dad_delay + 1);
1336 	}
1337 
1338 	return error;
1339 
1340   unlink:
1341 	/*
1342 	 * XXX: if a change of an existing address failed, keep the entry
1343 	 * anyway.
1344 	 */
1345 	if (hostIsNew)
1346 		in6_unlink_ifa(ia, ifp);
1347 	return error;
1348 
1349   cleanup:
1350 	in6_purgeaddr(&ia->ia_ifa);
1351 	return error;
1352 }
1353 
1354 int
1355 in6_update_ifa(struct ifnet *ifp, struct in6_aliasreq *ifra,
1356     struct in6_ifaddr *ia, int flags)
1357 {
1358 	int rc, s;
1359 
1360 	s = splnet();
1361 	rc = in6_update_ifa1(ifp, ifra, ia, flags);
1362 	splx(s);
1363 	return rc;
1364 }
1365 
1366 void
1367 in6_purgeaddr(struct ifaddr *ifa)
1368 {
1369 	struct ifnet *ifp = ifa->ifa_ifp;
1370 	struct in6_ifaddr *ia = (struct in6_ifaddr *) ifa;
1371 	struct in6_multi_mship *imm;
1372 
1373 	/* stop DAD processing */
1374 	nd6_dad_stop(ifa);
1375 
1376 	/*
1377 	 * delete route to the destination of the address being purged.
1378 	 * The interface must be p2p or loopback in this case.
1379 	 */
1380 	if ((ia->ia_flags & IFA_ROUTE) != 0 && ia->ia_dstaddr.sin6_len != 0) {
1381 		int e;
1382 
1383 		if ((e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
1384 		    != 0) {
1385 			log(LOG_ERR, "in6_purgeaddr: failed to remove "
1386 			    "a route to the p2p destination: %s on %s, "
1387 			    "errno=%d\n",
1388 			    ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
1389 			    e);
1390 			/* proceed anyway... */
1391 		} else
1392 			ia->ia_flags &= ~IFA_ROUTE;
1393 	}
1394 
1395 	/* Remove ownaddr's loopback rtentry, if it exists. */
1396 	in6_ifremloop(&(ia->ia_ifa));
1397 
1398 	/*
1399 	 * leave from multicast groups we have joined for the interface
1400 	 */
1401 	while ((imm = LIST_FIRST(&ia->ia6_memberships)) != NULL) {
1402 		LIST_REMOVE(imm, i6mm_chain);
1403 		in6_leavegroup(imm);
1404 	}
1405 
1406 	in6_unlink_ifa(ia, ifp);
1407 }
1408 
1409 static void
1410 in6_unlink_ifa(struct in6_ifaddr *ia, struct ifnet *ifp)
1411 {
1412 	struct in6_ifaddr *oia;
1413 	int	s = splnet();
1414 
1415 	ifa_remove(ifp, &ia->ia_ifa);
1416 
1417 	oia = ia;
1418 	if (oia == (ia = in6_ifaddr))
1419 		in6_ifaddr = ia->ia_next;
1420 	else {
1421 		while (ia->ia_next && (ia->ia_next != oia))
1422 			ia = ia->ia_next;
1423 		if (ia->ia_next)
1424 			ia->ia_next = oia->ia_next;
1425 		else {
1426 			/* search failed */
1427 			printf("Couldn't unlink in6_ifaddr from in6_ifaddr\n");
1428 		}
1429 	}
1430 
1431 	/*
1432 	 * XXX thorpej@NetBSD.org -- if the interface is going
1433 	 * XXX away, don't save the multicast entries, delete them!
1434 	 */
1435 	if (LIST_EMPTY(&oia->ia6_multiaddrs))
1436 		;
1437 	else if (oia->ia_ifa.ifa_ifp->if_output == if_nulloutput) {
1438 		struct in6_multi *in6m, *next;
1439 
1440 		for (in6m = LIST_FIRST(&oia->ia6_multiaddrs); in6m != NULL;
1441 		     in6m = next) {
1442 			next = LIST_NEXT(in6m, in6m_entry);
1443 			in6_delmulti(in6m);
1444 		}
1445 	} else
1446 		in6_savemkludge(oia);
1447 
1448 	/*
1449 	 * Release the reference to the base prefix.  There should be a
1450 	 * positive reference.
1451 	 */
1452 	if (oia->ia6_ndpr == NULL) {
1453 		nd6log((LOG_NOTICE, "in6_unlink_ifa: autoconf'ed address "
1454 		    "%p has no prefix\n", oia));
1455 	} else {
1456 		oia->ia6_ndpr->ndpr_refcnt--;
1457 		oia->ia6_ndpr = NULL;
1458 	}
1459 
1460 	/*
1461 	 * Also, if the address being removed is autoconf'ed, call
1462 	 * pfxlist_onlink_check() since the release might affect the status of
1463 	 * other (detached) addresses.
1464 	 */
1465 	if ((oia->ia6_flags & IN6_IFF_AUTOCONF) != 0)
1466 		pfxlist_onlink_check();
1467 
1468 	/*
1469 	 * release another refcnt for the link from in6_ifaddr.
1470 	 * Note that we should decrement the refcnt at least once for all *BSD.
1471 	 */
1472 	IFAFREE(&oia->ia_ifa);
1473 
1474 	splx(s);
1475 }
1476 
1477 void
1478 in6_purgeif(struct ifnet *ifp)
1479 {
1480 	if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr);
1481 
1482 	in6_ifdetach(ifp);
1483 }
1484 
1485 /*
1486  * SIOC[GAD]LIFADDR.
1487  *	SIOCGLIFADDR: get first address. (?)
1488  *	SIOCGLIFADDR with IFLR_PREFIX:
1489  *		get first address that matches the specified prefix.
1490  *	SIOCALIFADDR: add the specified address.
1491  *	SIOCALIFADDR with IFLR_PREFIX:
1492  *		add the specified prefix, filling hostid part from
1493  *		the first link-local address.  prefixlen must be <= 64.
1494  *	SIOCDLIFADDR: delete the specified address.
1495  *	SIOCDLIFADDR with IFLR_PREFIX:
1496  *		delete the first address that matches the specified prefix.
1497  * return values:
1498  *	EINVAL on invalid parameters
1499  *	EADDRNOTAVAIL on prefix match failed/specified address not found
1500  *	other values may be returned from in6_ioctl()
1501  *
1502  * NOTE: SIOCALIFADDR(with IFLR_PREFIX set) allows prefixlen less than 64.
1503  * this is to accommodate address naming scheme other than RFC2374,
1504  * in the future.
1505  * RFC2373 defines interface id to be 64bit, but it allows non-RFC2374
1506  * address encoding scheme. (see figure on page 8)
1507  */
1508 static int
1509 in6_lifaddr_ioctl(struct socket *so, u_long cmd, void *data,
1510 	struct ifnet *ifp)
1511 {
1512 	struct in6_ifaddr *ia;
1513 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
1514 	struct ifaddr *ifa;
1515 	struct sockaddr *sa;
1516 
1517 	/* sanity checks */
1518 	if (!data || !ifp) {
1519 		panic("invalid argument to in6_lifaddr_ioctl");
1520 		/* NOTREACHED */
1521 	}
1522 
1523 	switch (cmd) {
1524 	case SIOCGLIFADDR:
1525 		/* address must be specified on GET with IFLR_PREFIX */
1526 		if ((iflr->flags & IFLR_PREFIX) == 0)
1527 			break;
1528 		/* FALLTHROUGH */
1529 	case SIOCALIFADDR:
1530 	case SIOCDLIFADDR:
1531 		/* address must be specified on ADD and DELETE */
1532 		sa = (struct sockaddr *)&iflr->addr;
1533 		if (sa->sa_family != AF_INET6)
1534 			return EINVAL;
1535 		if (sa->sa_len != sizeof(struct sockaddr_in6))
1536 			return EINVAL;
1537 		/* XXX need improvement */
1538 		sa = (struct sockaddr *)&iflr->dstaddr;
1539 		if (sa->sa_family && sa->sa_family != AF_INET6)
1540 			return EINVAL;
1541 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in6))
1542 			return EINVAL;
1543 		break;
1544 	default: /* shouldn't happen */
1545 #if 0
1546 		panic("invalid cmd to in6_lifaddr_ioctl");
1547 		/* NOTREACHED */
1548 #else
1549 		return EOPNOTSUPP;
1550 #endif
1551 	}
1552 	if (sizeof(struct in6_addr) * NBBY < iflr->prefixlen)
1553 		return EINVAL;
1554 
1555 	switch (cmd) {
1556 	case SIOCALIFADDR:
1557 	    {
1558 		struct in6_aliasreq ifra;
1559 		struct in6_addr *xhostid = NULL;
1560 		int prefixlen;
1561 
1562 		if ((iflr->flags & IFLR_PREFIX) != 0) {
1563 			struct sockaddr_in6 *sin6;
1564 
1565 			/*
1566 			 * xhostid is to fill in the hostid part of the
1567 			 * address.  xhostid points to the first link-local
1568 			 * address attached to the interface.
1569 			 */
1570 			ia = in6ifa_ifpforlinklocal(ifp, 0);
1571 			if (ia == NULL)
1572 				return EADDRNOTAVAIL;
1573 			xhostid = IFA_IN6(&ia->ia_ifa);
1574 
1575 		 	/* prefixlen must be <= 64. */
1576 			if (64 < iflr->prefixlen)
1577 				return EINVAL;
1578 			prefixlen = iflr->prefixlen;
1579 
1580 			/* hostid part must be zero. */
1581 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1582 			if (sin6->sin6_addr.s6_addr32[2] != 0
1583 			 || sin6->sin6_addr.s6_addr32[3] != 0) {
1584 				return EINVAL;
1585 			}
1586 		} else
1587 			prefixlen = iflr->prefixlen;
1588 
1589 		/* copy args to in6_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
1590 		memset(&ifra, 0, sizeof(ifra));
1591 		memcpy(ifra.ifra_name, iflr->iflr_name, sizeof(ifra.ifra_name));
1592 
1593 		memcpy(&ifra.ifra_addr, &iflr->addr,
1594 		    ((struct sockaddr *)&iflr->addr)->sa_len);
1595 		if (xhostid) {
1596 			/* fill in hostid part */
1597 			ifra.ifra_addr.sin6_addr.s6_addr32[2] =
1598 			    xhostid->s6_addr32[2];
1599 			ifra.ifra_addr.sin6_addr.s6_addr32[3] =
1600 			    xhostid->s6_addr32[3];
1601 		}
1602 
1603 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) { /* XXX */
1604 			memcpy(&ifra.ifra_dstaddr, &iflr->dstaddr,
1605 			    ((struct sockaddr *)&iflr->dstaddr)->sa_len);
1606 			if (xhostid) {
1607 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[2] =
1608 				    xhostid->s6_addr32[2];
1609 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[3] =
1610 				    xhostid->s6_addr32[3];
1611 			}
1612 		}
1613 
1614 		ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
1615 		in6_prefixlen2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);
1616 
1617 		ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
1618 		ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
1619 		ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
1620 		return in6_control(so, SIOCAIFADDR_IN6, &ifra, ifp);
1621 	    }
1622 	case SIOCGLIFADDR:
1623 	case SIOCDLIFADDR:
1624 	    {
1625 		struct in6_addr mask, candidate, match;
1626 		struct sockaddr_in6 *sin6;
1627 		int cmp;
1628 
1629 		memset(&mask, 0, sizeof(mask));
1630 		if (iflr->flags & IFLR_PREFIX) {
1631 			/* lookup a prefix rather than address. */
1632 			in6_prefixlen2mask(&mask, iflr->prefixlen);
1633 
1634 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1635 			memcpy(&match, &sin6->sin6_addr, sizeof(match));
1636 			match.s6_addr32[0] &= mask.s6_addr32[0];
1637 			match.s6_addr32[1] &= mask.s6_addr32[1];
1638 			match.s6_addr32[2] &= mask.s6_addr32[2];
1639 			match.s6_addr32[3] &= mask.s6_addr32[3];
1640 
1641 			/* if you set extra bits, that's wrong */
1642 			if (memcmp(&match, &sin6->sin6_addr, sizeof(match)))
1643 				return EINVAL;
1644 
1645 			cmp = 1;
1646 		} else {
1647 			if (cmd == SIOCGLIFADDR) {
1648 				/* on getting an address, take the 1st match */
1649 				cmp = 0;	/* XXX */
1650 			} else {
1651 				/* on deleting an address, do exact match */
1652 				in6_prefixlen2mask(&mask, 128);
1653 				sin6 = (struct sockaddr_in6 *)&iflr->addr;
1654 				memcpy(&match, &sin6->sin6_addr, sizeof(match));
1655 
1656 				cmp = 1;
1657 			}
1658 		}
1659 
1660 		IFADDR_FOREACH(ifa, ifp) {
1661 			if (ifa->ifa_addr->sa_family != AF_INET6)
1662 				continue;
1663 			if (!cmp)
1664 				break;
1665 
1666 			/*
1667 			 * XXX: this is adhoc, but is necessary to allow
1668 			 * a user to specify fe80::/64 (not /10) for a
1669 			 * link-local address.
1670 			 */
1671 			memcpy(&candidate, IFA_IN6(ifa), sizeof(candidate));
1672 			in6_clearscope(&candidate);
1673 			candidate.s6_addr32[0] &= mask.s6_addr32[0];
1674 			candidate.s6_addr32[1] &= mask.s6_addr32[1];
1675 			candidate.s6_addr32[2] &= mask.s6_addr32[2];
1676 			candidate.s6_addr32[3] &= mask.s6_addr32[3];
1677 			if (IN6_ARE_ADDR_EQUAL(&candidate, &match))
1678 				break;
1679 		}
1680 		if (!ifa)
1681 			return EADDRNOTAVAIL;
1682 		ia = ifa2ia6(ifa);
1683 
1684 		if (cmd == SIOCGLIFADDR) {
1685 			int error;
1686 
1687 			/* fill in the if_laddrreq structure */
1688 			memcpy(&iflr->addr, &ia->ia_addr, ia->ia_addr.sin6_len);
1689 			error = sa6_recoverscope(
1690 			    (struct sockaddr_in6 *)&iflr->addr);
1691 			if (error != 0)
1692 				return error;
1693 
1694 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1695 				memcpy(&iflr->dstaddr, &ia->ia_dstaddr,
1696 				    ia->ia_dstaddr.sin6_len);
1697 				error = sa6_recoverscope(
1698 				    (struct sockaddr_in6 *)&iflr->dstaddr);
1699 				if (error != 0)
1700 					return error;
1701 			} else
1702 				memset(&iflr->dstaddr, 0, sizeof(iflr->dstaddr));
1703 
1704 			iflr->prefixlen =
1705 			    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
1706 
1707 			iflr->flags = ia->ia6_flags;	/* XXX */
1708 
1709 			return 0;
1710 		} else {
1711 			struct in6_aliasreq ifra;
1712 
1713 			/* fill in6_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
1714 			memset(&ifra, 0, sizeof(ifra));
1715 			memcpy(ifra.ifra_name, iflr->iflr_name,
1716 			    sizeof(ifra.ifra_name));
1717 
1718 			memcpy(&ifra.ifra_addr, &ia->ia_addr,
1719 			    ia->ia_addr.sin6_len);
1720 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1721 				memcpy(&ifra.ifra_dstaddr, &ia->ia_dstaddr,
1722 				    ia->ia_dstaddr.sin6_len);
1723 			} else {
1724 				memset(&ifra.ifra_dstaddr, 0,
1725 				    sizeof(ifra.ifra_dstaddr));
1726 			}
1727 			memcpy(&ifra.ifra_dstaddr, &ia->ia_prefixmask,
1728 			    ia->ia_prefixmask.sin6_len);
1729 
1730 			ifra.ifra_flags = ia->ia6_flags;
1731 			return in6_control(so, SIOCDIFADDR_IN6, &ifra, ifp);
1732 		}
1733 	    }
1734 	}
1735 
1736 	return EOPNOTSUPP;	/* just for safety */
1737 }
1738 
1739 /*
1740  * Initialize an interface's internet6 address
1741  * and routing table entry.
1742  */
1743 static int
1744 in6_ifinit(struct ifnet *ifp, struct in6_ifaddr *ia,
1745 	const struct sockaddr_in6 *sin6, int newhost)
1746 {
1747 	int	error = 0, plen, ifacount = 0;
1748 	int	s = splnet();
1749 	struct ifaddr *ifa;
1750 
1751 	/*
1752 	 * Give the interface a chance to initialize
1753 	 * if this is its first address,
1754 	 * and to validate the address if necessary.
1755 	 */
1756 	IFADDR_FOREACH(ifa, ifp) {
1757 		if (ifa->ifa_addr == NULL)
1758 			continue;	/* just for safety */
1759 		if (ifa->ifa_addr->sa_family != AF_INET6)
1760 			continue;
1761 		ifacount++;
1762 	}
1763 
1764 	ia->ia_addr = *sin6;
1765 
1766 	if (ifacount <= 1 &&
1767 	    (error = if_addr_init(ifp, &ia->ia_ifa, true)) != 0) {
1768 		splx(s);
1769 		return error;
1770 	}
1771 	splx(s);
1772 
1773 	ia->ia_ifa.ifa_metric = ifp->if_metric;
1774 
1775 	/* we could do in(6)_socktrim here, but just omit it at this moment. */
1776 
1777 	/*
1778 	 * Special case:
1779 	 * If the destination address is specified for a point-to-point
1780 	 * interface, install a route to the destination as an interface
1781 	 * direct route.
1782 	 */
1783 	plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
1784 	if (plen == 128 && ia->ia_dstaddr.sin6_family == AF_INET6) {
1785 		if ((error = rtinit(&ia->ia_ifa, RTM_ADD,
1786 				    RTF_UP | RTF_HOST)) != 0)
1787 			return error;
1788 		ia->ia_flags |= IFA_ROUTE;
1789 	}
1790 
1791 	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
1792 	if (newhost) {
1793 		/* set the rtrequest function to create llinfo */
1794 		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
1795 		in6_ifaddloop(&ia->ia_ifa);
1796 	} else {
1797 		/* Inform the routing socket of new flags/timings */
1798 		nd6_newaddrmsg(&ia->ia_ifa);
1799 	}
1800 
1801 	if (ifp->if_flags & IFF_MULTICAST)
1802 		in6_restoremkludge(ia, ifp);
1803 
1804 	return error;
1805 }
1806 
1807 static struct ifaddr *
1808 bestifa(struct ifaddr *best_ifa, struct ifaddr *ifa)
1809 {
1810 	if (best_ifa == NULL || best_ifa->ifa_preference < ifa->ifa_preference)
1811 		return ifa;
1812 	return best_ifa;
1813 }
1814 
1815 /*
1816  * Find an IPv6 interface link-local address specific to an interface.
1817  */
1818 struct in6_ifaddr *
1819 in6ifa_ifpforlinklocal(const struct ifnet *ifp, const int ignoreflags)
1820 {
1821 	struct ifaddr *best_ifa = NULL, *ifa;
1822 
1823 	IFADDR_FOREACH(ifa, ifp) {
1824 		if (ifa->ifa_addr == NULL)
1825 			continue;	/* just for safety */
1826 		if (ifa->ifa_addr->sa_family != AF_INET6)
1827 			continue;
1828 		if (!IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa)))
1829 			continue;
1830 		if ((((struct in6_ifaddr *)ifa)->ia6_flags & ignoreflags) != 0)
1831 			continue;
1832 		best_ifa = bestifa(best_ifa, ifa);
1833 	}
1834 
1835 	return (struct in6_ifaddr *)best_ifa;
1836 }
1837 
1838 
1839 /*
1840  * find the internet address corresponding to a given interface and address.
1841  */
1842 struct in6_ifaddr *
1843 in6ifa_ifpwithaddr(const struct ifnet *ifp, const struct in6_addr *addr)
1844 {
1845 	struct ifaddr *best_ifa = NULL, *ifa;
1846 
1847 	IFADDR_FOREACH(ifa, ifp) {
1848 		if (ifa->ifa_addr == NULL)
1849 			continue;	/* just for safety */
1850 		if (ifa->ifa_addr->sa_family != AF_INET6)
1851 			continue;
1852 		if (!IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa)))
1853 			continue;
1854 		best_ifa = bestifa(best_ifa, ifa);
1855 	}
1856 
1857 	return (struct in6_ifaddr *)best_ifa;
1858 }
1859 
1860 static struct in6_ifaddr *
1861 bestia(struct in6_ifaddr *best_ia, struct in6_ifaddr *ia)
1862 {
1863 	if (best_ia == NULL ||
1864 	    best_ia->ia_ifa.ifa_preference < ia->ia_ifa.ifa_preference)
1865 		return ia;
1866 	return best_ia;
1867 }
1868 
1869 /*
1870  * Convert IP6 address to printable (loggable) representation.
1871  */
1872 static int ip6round = 0;
1873 char *
1874 ip6_sprintf(const struct in6_addr *addr)
1875 {
1876 	static char ip6buf[8][48];
1877 	int i;
1878 	char *bp;
1879 	char *cp;
1880 	const u_int16_t *a = (const u_int16_t *)addr;
1881 	const u_int8_t *d;
1882 	int dcolon = 0;
1883 
1884 	ip6round = (ip6round + 1) & 7;
1885 	cp = ip6buf[ip6round];
1886 
1887 	for (i = 0; i < 8; i++) {
1888 		if (dcolon == 1) {
1889 			if (*a == 0) {
1890 				if (i == 7)
1891 					*cp++ = ':';
1892 				a++;
1893 				continue;
1894 			} else
1895 				dcolon = 2;
1896 		}
1897 		if (*a == 0) {
1898 			if (dcolon == 0 && *(a + 1) == 0) {
1899 				if (i == 0)
1900 					*cp++ = ':';
1901 				*cp++ = ':';
1902 				dcolon = 1;
1903 			} else {
1904 				*cp++ = '0';
1905 				*cp++ = ':';
1906 			}
1907 			a++;
1908 			continue;
1909 		}
1910 		d = (const u_char *)a;
1911 		bp = cp;
1912 		*cp = hexdigits[*d >> 4];
1913 		if (*cp != '0')
1914 			cp++;
1915 		*cp = hexdigits[*d++ & 0xf];
1916 		if (cp != bp || *cp != '0')
1917 			cp++;
1918 		*cp = hexdigits[*d >> 4];
1919 		if (cp != bp || *cp != '0')
1920 			cp++;
1921 		*cp++ = hexdigits[*d & 0xf];
1922 		*cp++ = ':';
1923 		a++;
1924 	}
1925 	*--cp = 0;
1926 	return ip6buf[ip6round];
1927 }
1928 
1929 /*
1930  * Determine if an address is on a local network.
1931  */
1932 int
1933 in6_localaddr(const struct in6_addr *in6)
1934 {
1935 	struct in6_ifaddr *ia;
1936 
1937 	if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6))
1938 		return 1;
1939 
1940 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
1941 		if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
1942 					      &ia->ia_prefixmask.sin6_addr))
1943 			return 1;
1944 
1945 	return 0;
1946 }
1947 
1948 int
1949 in6_is_addr_deprecated(struct sockaddr_in6 *sa6)
1950 {
1951 	struct in6_ifaddr *ia;
1952 
1953 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1954 		if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
1955 		    &sa6->sin6_addr) &&
1956 #ifdef SCOPEDROUTING
1957 		    ia->ia_addr.sin6_scope_id == sa6->sin6_scope_id &&
1958 #endif
1959 		    (ia->ia6_flags & IN6_IFF_DEPRECATED) != 0)
1960 			return 1; /* true */
1961 
1962 		/* XXX: do we still have to go thru the rest of the list? */
1963 	}
1964 
1965 	return 0;		/* false */
1966 }
1967 
1968 /*
1969  * return length of part which dst and src are equal
1970  * hard coding...
1971  */
1972 int
1973 in6_matchlen(struct in6_addr *src, struct in6_addr *dst)
1974 {
1975 	int match = 0;
1976 	u_char *s = (u_char *)src, *d = (u_char *)dst;
1977 	u_char *lim = s + 16, r;
1978 
1979 	while (s < lim)
1980 		if ((r = (*d++ ^ *s++)) != 0) {
1981 			while (r < 128) {
1982 				match++;
1983 				r <<= 1;
1984 			}
1985 			break;
1986 		} else
1987 			match += NBBY;
1988 	return match;
1989 }
1990 
1991 /* XXX: to be scope conscious */
1992 int
1993 in6_are_prefix_equal(struct in6_addr *p1, struct in6_addr *p2, int len)
1994 {
1995 	int bytelen, bitlen;
1996 
1997 	/* sanity check */
1998 	if (len < 0 || len > 128) {
1999 		log(LOG_ERR, "in6_are_prefix_equal: invalid prefix length(%d)\n",
2000 		    len);
2001 		return 0;
2002 	}
2003 
2004 	bytelen = len / NBBY;
2005 	bitlen = len % NBBY;
2006 
2007 	if (memcmp(&p1->s6_addr, &p2->s6_addr, bytelen))
2008 		return 0;
2009 	if (bitlen != 0 &&
2010 	    p1->s6_addr[bytelen] >> (NBBY - bitlen) !=
2011 	    p2->s6_addr[bytelen] >> (NBBY - bitlen))
2012 		return 0;
2013 
2014 	return 1;
2015 }
2016 
2017 void
2018 in6_prefixlen2mask(struct in6_addr *maskp, int len)
2019 {
2020 	static const u_char maskarray[NBBY] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
2021 	int bytelen, bitlen, i;
2022 
2023 	/* sanity check */
2024 	if (len < 0 || len > 128) {
2025 		log(LOG_ERR, "in6_prefixlen2mask: invalid prefix length(%d)\n",
2026 		    len);
2027 		return;
2028 	}
2029 
2030 	memset(maskp, 0, sizeof(*maskp));
2031 	bytelen = len / NBBY;
2032 	bitlen = len % NBBY;
2033 	for (i = 0; i < bytelen; i++)
2034 		maskp->s6_addr[i] = 0xff;
2035 	if (bitlen)
2036 		maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
2037 }
2038 
2039 /*
2040  * return the best address out of the same scope. if no address was
2041  * found, return the first valid address from designated IF.
2042  */
2043 struct in6_ifaddr *
2044 in6_ifawithifp(struct ifnet *ifp, struct in6_addr *dst)
2045 {
2046 	int dst_scope =	in6_addrscope(dst), blen = -1, tlen;
2047 	struct ifaddr *ifa;
2048 	struct in6_ifaddr *best_ia = NULL, *ia;
2049 	struct in6_ifaddr *dep[2];	/* last-resort: deprecated */
2050 
2051 	dep[0] = dep[1] = NULL;
2052 
2053 	/*
2054 	 * We first look for addresses in the same scope.
2055 	 * If there is one, return it.
2056 	 * If two or more, return one which matches the dst longest.
2057 	 * If none, return one of global addresses assigned other ifs.
2058 	 */
2059 	IFADDR_FOREACH(ifa, ifp) {
2060 		if (ifa->ifa_addr->sa_family != AF_INET6)
2061 			continue;
2062 		ia = (struct in6_ifaddr *)ifa;
2063 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2064 			continue; /* XXX: is there any case to allow anycast? */
2065 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2066 			continue; /* don't use this interface */
2067 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2068 			continue;
2069 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2070 			if (ip6_use_deprecated)
2071 				dep[0] = ia;
2072 			continue;
2073 		}
2074 
2075 		if (dst_scope != in6_addrscope(IFA_IN6(ifa)))
2076 			continue;
2077 		/*
2078 		 * call in6_matchlen() as few as possible
2079 		 */
2080 		if (best_ia == NULL) {
2081 			best_ia = ia;
2082 			continue;
2083 		}
2084 		if (blen == -1)
2085 			blen = in6_matchlen(&best_ia->ia_addr.sin6_addr, dst);
2086 		tlen = in6_matchlen(IFA_IN6(ifa), dst);
2087 		if (tlen > blen) {
2088 			blen = tlen;
2089 			best_ia = ia;
2090 		} else if (tlen == blen)
2091 			best_ia = bestia(best_ia, ia);
2092 	}
2093 	if (best_ia != NULL)
2094 		return best_ia;
2095 
2096 	IFADDR_FOREACH(ifa, ifp) {
2097 		if (ifa->ifa_addr->sa_family != AF_INET6)
2098 			continue;
2099 		ia = (struct in6_ifaddr *)ifa;
2100 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2101 			continue; /* XXX: is there any case to allow anycast? */
2102 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2103 			continue; /* don't use this interface */
2104 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2105 			continue;
2106 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2107 			if (ip6_use_deprecated)
2108 				dep[1] = (struct in6_ifaddr *)ifa;
2109 			continue;
2110 		}
2111 
2112 		best_ia = bestia(best_ia, ia);
2113 	}
2114 	if (best_ia != NULL)
2115 		return best_ia;
2116 
2117 	/* use the last-resort values, that are, deprecated addresses */
2118 	if (dep[0])
2119 		return dep[0];
2120 	if (dep[1])
2121 		return dep[1];
2122 
2123 	return NULL;
2124 }
2125 
2126 /*
2127  * perform DAD when interface becomes IFF_UP.
2128  */
2129 void
2130 in6_if_link_up(struct ifnet *ifp)
2131 {
2132 	struct ifaddr *ifa;
2133 	struct in6_ifaddr *ia;
2134 
2135 	/* Ensure it's sane to run DAD */
2136 	if (ifp->if_link_state == LINK_STATE_DOWN)
2137 		return;
2138 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
2139 		return;
2140 
2141 	IFADDR_FOREACH(ifa, ifp) {
2142 		if (ifa->ifa_addr->sa_family != AF_INET6)
2143 			continue;
2144 		ia = (struct in6_ifaddr *)ifa;
2145 
2146 		/* If detached then mark as tentative */
2147 		if (ia->ia6_flags & IN6_IFF_DETACHED) {
2148 			ia->ia6_flags &= ~IN6_IFF_DETACHED;
2149 			if (in6if_do_dad(ifp)) {
2150 				ia->ia6_flags |= IN6_IFF_TENTATIVE;
2151 				nd6log((LOG_ERR, "in6_if_up: "
2152 				    "%s marked tentative\n",
2153 				    ip6_sprintf(&ia->ia_addr.sin6_addr)));
2154 			} else if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0)
2155 				nd6_newaddrmsg(ifa);
2156 		}
2157 
2158 		if (ia->ia6_flags & IN6_IFF_TENTATIVE) {
2159 			int rand_delay;
2160 			/*
2161 			 * The TENTATIVE flag was likely set by hand
2162 			 * beforehand, implicitly indicating the need for DAD.
2163 			 * We may be able to skip the random delay in this
2164 			 * case, but we impose delays just in case.
2165 			 */
2166 			rand_delay = cprng_fast32() %
2167 			    (MAX_RTR_SOLICITATION_DELAY * hz);
2168 			/* +1 ensures callout is always used */
2169 			nd6_dad_start(ifa, rand_delay + 1);
2170 		}
2171 	}
2172 
2173 	/* Restore any detached prefixes */
2174 	pfxlist_onlink_check();
2175 }
2176 
2177 void
2178 in6_if_up(struct ifnet *ifp)
2179 {
2180 
2181 	/*
2182 	 * special cases, like 6to4, are handled in in6_ifattach
2183 	 */
2184 	in6_ifattach(ifp, NULL);
2185 
2186 	/* interface may not support link state, so bring it up also */
2187 	in6_if_link_up(ifp);
2188 }
2189 /*
2190  * Mark all addresses as detached.
2191  */
2192 void
2193 in6_if_link_down(struct ifnet *ifp)
2194 {
2195 	struct ifaddr *ifa;
2196 	struct in6_ifaddr *ia;
2197 
2198 	/* Any prefixes on this interface should be detached as well */
2199 	pfxlist_onlink_check();
2200 
2201 	IFADDR_FOREACH(ifa, ifp) {
2202 		if (ifa->ifa_addr->sa_family != AF_INET6)
2203 			continue;
2204 		ia = (struct in6_ifaddr *)ifa;
2205 
2206 		/* Stop DAD processing */
2207 		nd6_dad_stop(ifa);
2208 
2209 		/*
2210 		 * Mark the address as detached.
2211 		 * This satisfies RFC4862 Section 5.3, but we should apply
2212 		 * this logic to all addresses to be a good citizen and
2213 		 * avoid potential duplicated addresses.
2214 		 * When the interface comes up again, detached addresses
2215 		 * are marked tentative and DAD commences.
2216 		 */
2217 		if (!(ia->ia6_flags & IN6_IFF_DETACHED)) {
2218 			nd6log((LOG_DEBUG, "in6_if_down: "
2219 			    "%s marked detached\n",
2220 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
2221 			ia->ia6_flags |= IN6_IFF_DETACHED;
2222 			ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
2223 			nd6_newaddrmsg(ifa);
2224 		}
2225 	}
2226 }
2227 
2228 void
2229 in6_if_down(struct ifnet *ifp)
2230 {
2231 
2232 	in6_if_link_down(ifp);
2233 }
2234 
2235 int
2236 in6if_do_dad(struct ifnet *ifp)
2237 {
2238 	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2239 		return 0;
2240 
2241 	switch (ifp->if_type) {
2242 	case IFT_FAITH:
2243 		/*
2244 		 * These interfaces do not have the IFF_LOOPBACK flag,
2245 		 * but loop packets back.  We do not have to do DAD on such
2246 		 * interfaces.  We should even omit it, because loop-backed
2247 		 * NS would confuse the DAD procedure.
2248 		 */
2249 		return 0;
2250 	default:
2251 		/*
2252 		 * Our DAD routine requires the interface up and running.
2253 		 * However, some interfaces can be up before the RUNNING
2254 		 * status.  Additionaly, users may try to assign addresses
2255 		 * before the interface becomes up (or running).
2256 		 * We simply skip DAD in such a case as a work around.
2257 		 * XXX: we should rather mark "tentative" on such addresses,
2258 		 * and do DAD after the interface becomes ready.
2259 		 */
2260 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
2261 		    (IFF_UP|IFF_RUNNING))
2262 			return 0;
2263 
2264 		return 1;
2265 	}
2266 }
2267 
2268 /*
2269  * Calculate max IPv6 MTU through all the interfaces and store it
2270  * to in6_maxmtu.
2271  */
2272 void
2273 in6_setmaxmtu(void)
2274 {
2275 	unsigned long maxmtu = 0;
2276 	struct ifnet *ifp;
2277 
2278 	IFNET_FOREACH(ifp) {
2279 		/* this function can be called during ifnet initialization */
2280 		if (!ifp->if_afdata[AF_INET6])
2281 			continue;
2282 		if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
2283 		    IN6_LINKMTU(ifp) > maxmtu)
2284 			maxmtu = IN6_LINKMTU(ifp);
2285 	}
2286 	if (maxmtu)	     /* update only when maxmtu is positive */
2287 		in6_maxmtu = maxmtu;
2288 }
2289 
2290 /*
2291  * Provide the length of interface identifiers to be used for the link attached
2292  * to the given interface.  The length should be defined in "IPv6 over
2293  * xxx-link" document.  Note that address architecture might also define
2294  * the length for a particular set of address prefixes, regardless of the
2295  * link type.  As clarified in rfc2462bis, those two definitions should be
2296  * consistent, and those really are as of August 2004.
2297  */
2298 int
2299 in6_if2idlen(struct ifnet *ifp)
2300 {
2301 	switch (ifp->if_type) {
2302 	case IFT_ETHER:		/* RFC2464 */
2303 	case IFT_PROPVIRTUAL:	/* XXX: no RFC. treat it as ether */
2304 	case IFT_L2VLAN:	/* ditto */
2305 	case IFT_IEEE80211:	/* ditto */
2306 	case IFT_FDDI:		/* RFC2467 */
2307 	case IFT_ISO88025:	/* RFC2470 (IPv6 over Token Ring) */
2308 	case IFT_PPP:		/* RFC2472 */
2309 	case IFT_ARCNET:	/* RFC2497 */
2310 	case IFT_FRELAY:	/* RFC2590 */
2311 	case IFT_IEEE1394:	/* RFC3146 */
2312 	case IFT_GIF:		/* draft-ietf-v6ops-mech-v2-07 */
2313 	case IFT_LOOP:		/* XXX: is this really correct? */
2314 		return 64;
2315 	default:
2316 		/*
2317 		 * Unknown link type:
2318 		 * It might be controversial to use the today's common constant
2319 		 * of 64 for these cases unconditionally.  For full compliance,
2320 		 * we should return an error in this case.  On the other hand,
2321 		 * if we simply miss the standard for the link type or a new
2322 		 * standard is defined for a new link type, the IFID length
2323 		 * is very likely to be the common constant.  As a compromise,
2324 		 * we always use the constant, but make an explicit notice
2325 		 * indicating the "unknown" case.
2326 		 */
2327 		printf("in6_if2idlen: unknown link type (%d)\n", ifp->if_type);
2328 		return 64;
2329 	}
2330 }
2331 
2332 void *
2333 in6_domifattach(struct ifnet *ifp)
2334 {
2335 	struct in6_ifextra *ext;
2336 
2337 	ext = malloc(sizeof(*ext), M_IFADDR, M_WAITOK|M_ZERO);
2338 
2339 	ext->in6_ifstat = malloc(sizeof(struct in6_ifstat),
2340 	    M_IFADDR, M_WAITOK|M_ZERO);
2341 
2342 	ext->icmp6_ifstat = malloc(sizeof(struct icmp6_ifstat),
2343 	    M_IFADDR, M_WAITOK|M_ZERO);
2344 
2345 	ext->nd_ifinfo = nd6_ifattach(ifp);
2346 	ext->scope6_id = scope6_ifattach(ifp);
2347 	ext->nprefixes = 0;
2348 	ext->ndefrouters = 0;
2349 	return ext;
2350 }
2351 
2352 void
2353 in6_domifdetach(struct ifnet *ifp, void *aux)
2354 {
2355 	struct in6_ifextra *ext = (struct in6_ifextra *)aux;
2356 
2357 	nd6_ifdetach(ext->nd_ifinfo);
2358 	free(ext->in6_ifstat, M_IFADDR);
2359 	free(ext->icmp6_ifstat, M_IFADDR);
2360 	scope6_ifdetach(ext->scope6_id);
2361 	free(ext, M_IFADDR);
2362 }
2363 
2364 /*
2365  * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
2366  * v4 mapped addr or v4 compat addr
2367  */
2368 void
2369 in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2370 {
2371 	memset(sin, 0, sizeof(*sin));
2372 	sin->sin_len = sizeof(struct sockaddr_in);
2373 	sin->sin_family = AF_INET;
2374 	sin->sin_port = sin6->sin6_port;
2375 	sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];
2376 }
2377 
2378 /* Convert sockaddr_in to sockaddr_in6 in v4 mapped addr format. */
2379 void
2380 in6_sin_2_v4mapsin6(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2381 {
2382 	memset(sin6, 0, sizeof(*sin6));
2383 	sin6->sin6_len = sizeof(struct sockaddr_in6);
2384 	sin6->sin6_family = AF_INET6;
2385 	sin6->sin6_port = sin->sin_port;
2386 	sin6->sin6_addr.s6_addr32[0] = 0;
2387 	sin6->sin6_addr.s6_addr32[1] = 0;
2388 	sin6->sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
2389 	sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;
2390 }
2391 
2392 /* Convert sockaddr_in6 into sockaddr_in. */
2393 void
2394 in6_sin6_2_sin_in_sock(struct sockaddr *nam)
2395 {
2396 	struct sockaddr_in *sin_p;
2397 	struct sockaddr_in6 sin6;
2398 
2399 	/*
2400 	 * Save original sockaddr_in6 addr and convert it
2401 	 * to sockaddr_in.
2402 	 */
2403 	sin6 = *(struct sockaddr_in6 *)nam;
2404 	sin_p = (struct sockaddr_in *)nam;
2405 	in6_sin6_2_sin(sin_p, &sin6);
2406 }
2407 
2408 /* Convert sockaddr_in into sockaddr_in6 in v4 mapped addr format. */
2409 void
2410 in6_sin_2_v4mapsin6_in_sock(struct sockaddr **nam)
2411 {
2412 	struct sockaddr_in *sin_p;
2413 	struct sockaddr_in6 *sin6_p;
2414 
2415 	sin6_p = malloc(sizeof(*sin6_p), M_SONAME, M_WAITOK);
2416 	sin_p = (struct sockaddr_in *)*nam;
2417 	in6_sin_2_v4mapsin6(sin_p, sin6_p);
2418 	free(*nam, M_SONAME);
2419 	*nam = (struct sockaddr *)sin6_p;
2420 }
2421