xref: /netbsd-src/sys/netinet6/in6.c (revision 7788a0781fe6ff2cce37368b4578a7ade0850cb1)
1 /*	$NetBSD: in6.c,v 1.166 2013/06/29 21:06:58 rmind 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 1.166 2013/06/29 21:06:58 rmind 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 *, struct lwp *);
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 lo_sa;
155 	struct sockaddr_in6 all1_sa;
156 	struct rtentry *nrt = NULL;
157 	int e;
158 
159 	sockaddr_in6_init(&all1_sa, &in6mask128, 0, 0, 0);
160 	sockaddr_in6_init(&lo_sa, &in6addr_loopback, 0, 0, 0);
161 
162 	/*
163 	 * We specify the address itself as the gateway, and set the
164 	 * RTF_LLINFO flag, so that the corresponding host route would have
165 	 * the flag, and thus applications that assume traditional behavior
166 	 * would be happy.  Note that we assume the caller of the function
167 	 * (probably implicitly) set nd6_rtrequest() to ifa->ifa_rtrequest,
168 	 * which changes the outgoing interface to the loopback interface.
169 	 */
170 	e = rtrequest(cmd, ifa->ifa_addr, ifa->ifa_addr,
171 	    (struct sockaddr *)&all1_sa, RTF_UP|RTF_HOST|RTF_LLINFO, &nrt);
172 	if (e != 0) {
173 		log(LOG_ERR, "in6_ifloop_request: "
174 		    "%s operation failed for %s (errno=%d)\n",
175 		    cmd == RTM_ADD ? "ADD" : "DELETE",
176 		    ip6_sprintf(&((struct in6_ifaddr *)ifa)->ia_addr.sin6_addr),
177 		    e);
178 	}
179 
180 	/*
181 	 * Make sure rt_ifa be equal to IFA, the second argument of the
182 	 * function.
183 	 * We need this because when we refer to rt_ifa->ia6_flags in
184 	 * ip6_input, we assume that the rt_ifa points to the address instead
185 	 * of the loopback address.
186 	 */
187 	if (cmd == RTM_ADD && nrt && ifa != nrt->rt_ifa)
188 		rt_replace_ifa(nrt, ifa);
189 
190 	/*
191 	 * Report the addition/removal of the address to the routing socket
192 	 * unless the address is marked tentative, where it will be reported
193 	 * once DAD completes.
194 	 * XXX: since we called rtinit for a p2p interface with a destination,
195 	 *      we end up reporting twice in such a case.  Should we rather
196 	 *      omit the second report?
197 	 */
198 	if (nrt) {
199 		if (cmd != RTM_ADD ||
200 		    !(((struct in6_ifaddr *)ifa)->ia6_flags &IN6_IFF_TENTATIVE))
201 		{
202 #if 0
203 			struct in6_ifaddr *ia;
204 
205 			ia = (struct in6_ifaddr *)ifa;
206 			log(LOG_DEBUG,
207 			    "in6_ifloop_request: announced %s (%s %d)\n",
208 			    ip6_sprintf(&ia->ia_addr.sin6_addr),
209 			    cmd == RTM_ADD ? "RTM_ADD" : "RTM_DELETE",
210 			    ia->ia6_flags);
211 #endif
212 			rt_newaddrmsg(cmd, ifa, e, nrt);
213 		}
214 		if (cmd == RTM_DELETE) {
215 			if (nrt->rt_refcnt <= 0) {
216 				/* XXX: we should free the entry ourselves. */
217 				nrt->rt_refcnt++;
218 				rtfree(nrt);
219 			}
220 		} else {
221 			/* the cmd must be RTM_ADD here */
222 			nrt->rt_refcnt--;
223 		}
224 	}
225 }
226 
227 /*
228  * Add ownaddr as loopback rtentry.  We previously add the route only if
229  * necessary (ex. on a p2p link).  However, since we now manage addresses
230  * separately from prefixes, we should always add the route.  We can't
231  * rely on the cloning mechanism from the corresponding interface route
232  * any more.
233  */
234 void
235 in6_ifaddloop(struct ifaddr *ifa)
236 {
237 	struct rtentry *rt;
238 
239 	/* If there is no loopback entry, allocate one. */
240 	rt = rtalloc1(ifa->ifa_addr, 0);
241 	if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0 ||
242 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
243 		in6_ifloop_request(RTM_ADD, ifa);
244 	if (rt != NULL)
245 		rt->rt_refcnt--;
246 }
247 
248 /*
249  * Remove loopback rtentry of ownaddr generated by in6_ifaddloop(),
250  * if it exists.
251  */
252 void
253 in6_ifremloop(struct ifaddr *ifa)
254 {
255 	struct in6_ifaddr *alt_ia = NULL, *ia;
256 	struct rtentry *rt;
257 	int ia_count = 0;
258 
259 	/*
260 	 * Some of BSD variants do not remove cloned routes
261 	 * from an interface direct route, when removing the direct route
262 	 * (see comments in net/net_osdep.h).  Even for variants that do remove
263 	 * cloned routes, they could fail to remove the cloned routes when
264 	 * we handle multple addresses that share a common prefix.
265 	 * So, we should remove the route corresponding to the deleted address.
266 	 */
267 
268 	/*
269 	 * Delete the entry only if exactly one ifaddr matches the
270 	 * address, ifa->ifa_addr.
271 	 *
272 	 * If more than one ifaddr matches, replace the ifaddr in
273 	 * the routing table, rt_ifa, with a different ifaddr than
274 	 * the one we are purging, ifa.  It is important to do
275 	 * this, or else the routing table can accumulate dangling
276 	 * pointers rt->rt_ifa->ifa_ifp to destroyed interfaces,
277 	 * which will lead to crashes, later.  (More than one ifaddr
278 	 * can match if we assign the same address to multiple---probably
279 	 * p2p---interfaces.)
280 	 *
281 	 * XXX An old comment at this place said, "we should avoid
282 	 * XXX such a configuration [i.e., interfaces with the same
283 	 * XXX addressed assigned --ed.] in IPv6...".  I do not
284 	 * XXX agree, especially now that I have fixed the dangling
285 	 * XXX ifp-pointers bug.
286 	 */
287 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
288 		if (!IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ia->ia_addr.sin6_addr))
289 			continue;
290 		if (ia->ia_ifp != ifa->ifa_ifp)
291 			alt_ia = ia;
292 		if (++ia_count > 1 && alt_ia != NULL)
293 			break;
294 	}
295 
296 	if (ia_count == 0)
297 		return;
298 
299 	if ((rt = rtalloc1(ifa->ifa_addr, 0)) == NULL)
300 		return;
301 	rt->rt_refcnt--;
302 
303 	/*
304 	 * Before deleting, check if a corresponding loopbacked
305 	 * host route surely exists.  With this check, we can avoid
306 	 * deleting an interface direct route whose destination is
307 	 * the same as the address being removed.  This can happen
308 	 * when removing a subnet-router anycast address on an
309 	 * interface attached to a shared medium.
310 	 */
311 	if ((rt->rt_flags & RTF_HOST) == 0 ||
312 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
313 		return;
314 
315 	/* If we cannot replace the route's ifaddr with the equivalent
316 	 * ifaddr of another interface, I believe it is safest to
317 	 * delete the route.
318 	 */
319 	if (ia_count == 1 || alt_ia == NULL)
320 		in6_ifloop_request(RTM_DELETE, ifa);
321 	else
322 		rt_replace_ifa(rt, &alt_ia->ia_ifa);
323 }
324 
325 int
326 in6_mask2len(struct in6_addr *mask, u_char *lim0)
327 {
328 	int x = 0, y;
329 	u_char *lim = lim0, *p;
330 
331 	/* ignore the scope_id part */
332 	if (lim0 == NULL || lim0 - (u_char *)mask > sizeof(*mask))
333 		lim = (u_char *)mask + sizeof(*mask);
334 	for (p = (u_char *)mask; p < lim; x++, p++) {
335 		if (*p != 0xff)
336 			break;
337 	}
338 	y = 0;
339 	if (p < lim) {
340 		for (y = 0; y < NBBY; y++) {
341 			if ((*p & (0x80 >> y)) == 0)
342 				break;
343 		}
344 	}
345 
346 	/*
347 	 * when the limit pointer is given, do a stricter check on the
348 	 * remaining bits.
349 	 */
350 	if (p < lim) {
351 		if (y != 0 && (*p & (0x00ff >> y)) != 0)
352 			return -1;
353 		for (p = p + 1; p < lim; p++)
354 			if (*p != 0)
355 				return -1;
356 	}
357 
358 	return x * NBBY + y;
359 }
360 
361 #define ifa2ia6(ifa)	((struct in6_ifaddr *)(ifa))
362 #define ia62ifa(ia6)	(&((ia6)->ia_ifa))
363 
364 static int
365 in6_control1(struct socket *so, u_long cmd, void *data, struct ifnet *ifp,
366     lwp_t *l)
367 {
368 	struct	in6_ifreq *ifr = (struct in6_ifreq *)data;
369 	struct	in6_ifaddr *ia = NULL;
370 	struct	in6_aliasreq *ifra = (struct in6_aliasreq *)data;
371 	struct sockaddr_in6 *sa6;
372 	int error;
373 
374 	switch (cmd) {
375 	/*
376 	 * XXX: Fix me, once we fix SIOCSIFADDR, SIOCIFDSTADDR, etc.
377 	 */
378 	case SIOCSIFADDR:
379 	case SIOCSIFDSTADDR:
380 #ifdef SIOCSIFCONF_X25
381 	case SIOCSIFCONF_X25:
382 #endif
383 		return EOPNOTSUPP;
384 	case SIOCGETSGCNT_IN6:
385 	case SIOCGETMIFCNT_IN6:
386 		return mrt6_ioctl(cmd, data);
387 	case SIOCGIFADDRPREF:
388 	case SIOCSIFADDRPREF:
389 		if (ifp == NULL)
390 			return EINVAL;
391 		return ifaddrpref_ioctl(so, cmd, data, ifp, l);
392 	}
393 
394 	if (ifp == NULL)
395 		return EOPNOTSUPP;
396 
397 	switch (cmd) {
398 	case SIOCSNDFLUSH_IN6:
399 	case SIOCSPFXFLUSH_IN6:
400 	case SIOCSRTRFLUSH_IN6:
401 	case SIOCSDEFIFACE_IN6:
402 	case SIOCSIFINFO_FLAGS:
403 	case SIOCSIFINFO_IN6:
404 		/* Privileged. */
405 		/* FALLTHROUGH */
406 	case OSIOCGIFINFO_IN6:
407 	case SIOCGIFINFO_IN6:
408 	case SIOCGDRLST_IN6:
409 	case SIOCGPRLST_IN6:
410 	case SIOCGNBRINFO_IN6:
411 	case SIOCGDEFIFACE_IN6:
412 		return nd6_ioctl(cmd, data, ifp);
413 	}
414 
415 	switch (cmd) {
416 	case SIOCSIFPREFIX_IN6:
417 	case SIOCDIFPREFIX_IN6:
418 	case SIOCAIFPREFIX_IN6:
419 	case SIOCCIFPREFIX_IN6:
420 	case SIOCSGIFPREFIX_IN6:
421 	case SIOCGIFPREFIX_IN6:
422 		log(LOG_NOTICE,
423 		    "prefix ioctls are now invalidated. "
424 		    "please use ifconfig.\n");
425 		return EOPNOTSUPP;
426 	}
427 
428 	switch (cmd) {
429 	case SIOCALIFADDR:
430 	case SIOCDLIFADDR:
431 		/* Privileged. */
432 		/* FALLTHROUGH */
433 	case SIOCGLIFADDR:
434 		return in6_lifaddr_ioctl(so, cmd, data, ifp, l);
435 	}
436 
437 	/*
438 	 * Find address for this interface, if it exists.
439 	 *
440 	 * In netinet code, we have checked ifra_addr in SIOCSIF*ADDR operation
441 	 * only, and used the first interface address as the target of other
442 	 * operations (without checking ifra_addr).  This was because netinet
443 	 * code/API assumed at most 1 interface address per interface.
444 	 * Since IPv6 allows a node to assign multiple addresses
445 	 * on a single interface, we almost always look and check the
446 	 * presence of ifra_addr, and reject invalid ones here.
447 	 * It also decreases duplicated code among SIOC*_IN6 operations.
448 	 */
449 	switch (cmd) {
450 	case SIOCAIFADDR_IN6:
451 #ifdef OSIOCAIFADDR_IN6
452 	case OSIOCAIFADDR_IN6:
453 #endif
454 #ifdef OSIOCSIFPHYADDR_IN6
455 	case OSIOCSIFPHYADDR_IN6:
456 #endif
457 	case SIOCSIFPHYADDR_IN6:
458 		sa6 = &ifra->ifra_addr;
459 		break;
460 	case SIOCSIFADDR_IN6:
461 	case SIOCGIFADDR_IN6:
462 	case SIOCSIFDSTADDR_IN6:
463 	case SIOCSIFNETMASK_IN6:
464 	case SIOCGIFDSTADDR_IN6:
465 	case SIOCGIFNETMASK_IN6:
466 	case SIOCDIFADDR_IN6:
467 	case SIOCGIFPSRCADDR_IN6:
468 	case SIOCGIFPDSTADDR_IN6:
469 	case SIOCGIFAFLAG_IN6:
470 	case SIOCSNDFLUSH_IN6:
471 	case SIOCSPFXFLUSH_IN6:
472 	case SIOCSRTRFLUSH_IN6:
473 	case SIOCGIFALIFETIME_IN6:
474 #ifdef OSIOCGIFALIFETIME_IN6
475 	case OSIOCGIFALIFETIME_IN6:
476 #endif
477 	case SIOCGIFSTAT_IN6:
478 	case SIOCGIFSTAT_ICMP6:
479 		sa6 = &ifr->ifr_addr;
480 		break;
481 	default:
482 		sa6 = NULL;
483 		break;
484 	}
485 	if (sa6 && sa6->sin6_family == AF_INET6) {
486 		if (sa6->sin6_scope_id != 0)
487 			error = sa6_embedscope(sa6, 0);
488 		else
489 			error = in6_setscope(&sa6->sin6_addr, ifp, NULL);
490 		if (error != 0)
491 			return error;
492 		ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
493 	} else
494 		ia = NULL;
495 
496 	switch (cmd) {
497 	case SIOCSIFADDR_IN6:
498 	case SIOCSIFDSTADDR_IN6:
499 	case SIOCSIFNETMASK_IN6:
500 		/*
501 		 * Since IPv6 allows a node to assign multiple addresses
502 		 * on a single interface, SIOCSIFxxx ioctls are deprecated.
503 		 */
504 		return EINVAL;
505 
506 	case SIOCDIFADDR_IN6:
507 		/*
508 		 * for IPv4, we look for existing in_ifaddr here to allow
509 		 * "ifconfig if0 delete" to remove the first IPv4 address on
510 		 * the interface.  For IPv6, as the spec allows multiple
511 		 * interface address from the day one, we consider "remove the
512 		 * first one" semantics to be not preferable.
513 		 */
514 		if (ia == NULL)
515 			return EADDRNOTAVAIL;
516 		/* FALLTHROUGH */
517 #ifdef OSIOCAIFADDR_IN6
518 	case OSIOCAIFADDR_IN6:
519 #endif
520 	case SIOCAIFADDR_IN6:
521 		/*
522 		 * We always require users to specify a valid IPv6 address for
523 		 * the corresponding operation.
524 		 */
525 		if (ifra->ifra_addr.sin6_family != AF_INET6 ||
526 		    ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6))
527 			return EAFNOSUPPORT;
528 		/* Privileged. */
529 
530 		break;
531 
532 	case SIOCGIFADDR_IN6:
533 		/* This interface is basically deprecated. use SIOCGIFCONF. */
534 		/* FALLTHROUGH */
535 	case SIOCGIFAFLAG_IN6:
536 	case SIOCGIFNETMASK_IN6:
537 	case SIOCGIFDSTADDR_IN6:
538 	case SIOCGIFALIFETIME_IN6:
539 #ifdef OSIOCGIFALIFETIME_IN6
540 	case OSIOCGIFALIFETIME_IN6:
541 #endif
542 		/* must think again about its semantics */
543 		if (ia == NULL)
544 			return EADDRNOTAVAIL;
545 		break;
546 	}
547 
548 	switch (cmd) {
549 
550 	case SIOCGIFADDR_IN6:
551 		ifr->ifr_addr = ia->ia_addr;
552 		if ((error = sa6_recoverscope(&ifr->ifr_addr)) != 0)
553 			return error;
554 		break;
555 
556 	case SIOCGIFDSTADDR_IN6:
557 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
558 			return EINVAL;
559 		/*
560 		 * XXX: should we check if ifa_dstaddr is NULL and return
561 		 * an error?
562 		 */
563 		ifr->ifr_dstaddr = ia->ia_dstaddr;
564 		if ((error = sa6_recoverscope(&ifr->ifr_dstaddr)) != 0)
565 			return error;
566 		break;
567 
568 	case SIOCGIFNETMASK_IN6:
569 		ifr->ifr_addr = ia->ia_prefixmask;
570 		break;
571 
572 	case SIOCGIFAFLAG_IN6:
573 		ifr->ifr_ifru.ifru_flags6 = ia->ia6_flags;
574 		break;
575 
576 	case SIOCGIFSTAT_IN6:
577 		if (ifp == NULL)
578 			return EINVAL;
579 		memset(&ifr->ifr_ifru.ifru_stat, 0,
580 		    sizeof(ifr->ifr_ifru.ifru_stat));
581 		ifr->ifr_ifru.ifru_stat =
582 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->in6_ifstat;
583 		break;
584 
585 	case SIOCGIFSTAT_ICMP6:
586 		if (ifp == NULL)
587 			return EINVAL;
588 		memset(&ifr->ifr_ifru.ifru_icmp6stat, 0,
589 		    sizeof(ifr->ifr_ifru.ifru_icmp6stat));
590 		ifr->ifr_ifru.ifru_icmp6stat =
591 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->icmp6_ifstat;
592 		break;
593 
594 #ifdef OSIOCGIFALIFETIME_IN6
595 	case OSIOCGIFALIFETIME_IN6:
596 #endif
597 	case SIOCGIFALIFETIME_IN6:
598 		ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
599 		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
600 			time_t maxexpire;
601 			struct in6_addrlifetime *retlt =
602 			    &ifr->ifr_ifru.ifru_lifetime;
603 
604 			/*
605 			 * XXX: adjust expiration time assuming time_t is
606 			 * signed.
607 			 */
608 			maxexpire = ((time_t)~0) &
609 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
610 			if (ia->ia6_lifetime.ia6t_vltime <
611 			    maxexpire - ia->ia6_updatetime) {
612 				retlt->ia6t_expire = ia->ia6_updatetime +
613 				    ia->ia6_lifetime.ia6t_vltime;
614 			} else
615 				retlt->ia6t_expire = maxexpire;
616 		}
617 		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
618 			time_t maxexpire;
619 			struct in6_addrlifetime *retlt =
620 			    &ifr->ifr_ifru.ifru_lifetime;
621 
622 			/*
623 			 * XXX: adjust expiration time assuming time_t is
624 			 * signed.
625 			 */
626 			maxexpire = ((time_t)~0) &
627 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
628 			if (ia->ia6_lifetime.ia6t_pltime <
629 			    maxexpire - ia->ia6_updatetime) {
630 				retlt->ia6t_preferred = ia->ia6_updatetime +
631 				    ia->ia6_lifetime.ia6t_pltime;
632 			} else
633 				retlt->ia6t_preferred = maxexpire;
634 		}
635 #ifdef OSIOCFIFALIFETIME_IN6
636 		if (cmd == OSIOCFIFALIFETIME_IN6)
637 			in6_addrlifetime_to_in6_addrlifetime50(
638 			    &ifr->ifru.ifru_lifetime);
639 #endif
640 		break;
641 
642 #ifdef OSIOCAIFADDR_IN6
643 	case OSIOCAIFADDR_IN6:
644 		in6_aliasreq50_to_in6_aliasreq(ifra);
645 		/*FALLTHROUGH*/
646 #endif
647 	case SIOCAIFADDR_IN6:
648 	{
649 		int i;
650 		struct nd_prefixctl pr0;
651 		struct nd_prefix *pr;
652 
653 		/* reject read-only flags */
654 		if ((ifra->ifra_flags & IN6_IFF_DUPLICATED) != 0 ||
655 		    (ifra->ifra_flags & IN6_IFF_DETACHED) != 0 ||
656 		    (ifra->ifra_flags & IN6_IFF_NODAD) != 0 ||
657 		    (ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0) {
658 			return EINVAL;
659 		}
660 		/*
661 		 * first, make or update the interface address structure,
662 		 * and link it to the list.
663 		 */
664 		if ((error = in6_update_ifa(ifp, ifra, ia, 0)) != 0)
665 			return error;
666 		if ((ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr))
667 		    == NULL) {
668 		    	/*
669 			 * this can happen when the user specify the 0 valid
670 			 * lifetime.
671 			 */
672 			break;
673 		}
674 
675 		/*
676 		 * then, make the prefix on-link on the interface.
677 		 * XXX: we'd rather create the prefix before the address, but
678 		 * we need at least one address to install the corresponding
679 		 * interface route, so we configure the address first.
680 		 */
681 
682 		/*
683 		 * convert mask to prefix length (prefixmask has already
684 		 * been validated in in6_update_ifa().
685 		 */
686 		memset(&pr0, 0, sizeof(pr0));
687 		pr0.ndpr_ifp = ifp;
688 		pr0.ndpr_plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
689 		    NULL);
690 		if (pr0.ndpr_plen == 128) {
691 			break;	/* we don't need to install a host route. */
692 		}
693 		pr0.ndpr_prefix = ifra->ifra_addr;
694 		/* apply the mask for safety. */
695 		for (i = 0; i < 4; i++) {
696 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
697 			    ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
698 		}
699 		/*
700 		 * XXX: since we don't have an API to set prefix (not address)
701 		 * lifetimes, we just use the same lifetimes as addresses.
702 		 * The (temporarily) installed lifetimes can be overridden by
703 		 * later advertised RAs (when accept_rtadv is non 0), which is
704 		 * an intended behavior.
705 		 */
706 		pr0.ndpr_raf_onlink = 1; /* should be configurable? */
707 		pr0.ndpr_raf_auto =
708 		    ((ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0);
709 		pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
710 		pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;
711 
712 		/* add the prefix if not yet. */
713 		if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
714 			/*
715 			 * nd6_prelist_add will install the corresponding
716 			 * interface route.
717 			 */
718 			if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
719 				return error;
720 			if (pr == NULL) {
721 				log(LOG_ERR, "nd6_prelist_add succeeded but "
722 				    "no prefix\n");
723 				return EINVAL; /* XXX panic here? */
724 			}
725 		}
726 
727 		/* relate the address to the prefix */
728 		if (ia->ia6_ndpr == NULL) {
729 			ia->ia6_ndpr = pr;
730 			pr->ndpr_refcnt++;
731 
732 			/*
733 			 * If this is the first autoconf address from the
734 			 * prefix, create a temporary address as well
735 			 * (when required).
736 			 */
737 			if ((ia->ia6_flags & IN6_IFF_AUTOCONF) &&
738 			    ip6_use_tempaddr && pr->ndpr_refcnt == 1) {
739 				int e;
740 				if ((e = in6_tmpifadd(ia, 1, 0)) != 0) {
741 					log(LOG_NOTICE, "in6_control: failed "
742 					    "to create a temporary address, "
743 					    "errno=%d\n", e);
744 				}
745 			}
746 		}
747 
748 		/*
749 		 * this might affect the status of autoconfigured addresses,
750 		 * that is, this address might make other addresses detached.
751 		 */
752 		pfxlist_onlink_check();
753 
754 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCAIFADDR_IN6,
755 		    ifp, PFIL_IFADDR);
756 		break;
757 	}
758 
759 	case SIOCDIFADDR_IN6:
760 	{
761 		struct nd_prefix *pr;
762 
763 		/*
764 		 * If the address being deleted is the only one that owns
765 		 * the corresponding prefix, expire the prefix as well.
766 		 * XXX: theoretically, we don't have to worry about such
767 		 * relationship, since we separate the address management
768 		 * and the prefix management.  We do this, however, to provide
769 		 * as much backward compatibility as possible in terms of
770 		 * the ioctl operation.
771 		 * Note that in6_purgeaddr() will decrement ndpr_refcnt.
772 		 */
773 		pr = ia->ia6_ndpr;
774 		in6_purgeaddr(&ia->ia_ifa);
775 		if (pr && pr->ndpr_refcnt == 0)
776 			prelist_remove(pr);
777 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCDIFADDR_IN6,
778 		    ifp, PFIL_IFADDR);
779 		break;
780 	}
781 
782 	default:
783 		return ENOTTY;
784 	}
785 
786 	return 0;
787 }
788 
789 int
790 in6_control(struct socket *so, u_long cmd, void *data, struct ifnet *ifp,
791     struct lwp *l)
792 {
793 	int error, s;
794 
795 	switch (cmd) {
796 	case SIOCSNDFLUSH_IN6:
797 	case SIOCSPFXFLUSH_IN6:
798 	case SIOCSRTRFLUSH_IN6:
799 	case SIOCSDEFIFACE_IN6:
800 	case SIOCSIFINFO_FLAGS:
801 	case SIOCSIFINFO_IN6:
802 
803 	case SIOCALIFADDR:
804 	case SIOCDLIFADDR:
805 
806 	case SIOCDIFADDR_IN6:
807 #ifdef OSIOCAIFADDR_IN6
808 	case OSIOCAIFADDR_IN6:
809 #endif
810 	case SIOCAIFADDR_IN6:
811 		if (kauth_authorize_network(l->l_cred,
812 		    KAUTH_NETWORK_SOCKET,
813 		    KAUTH_REQ_NETWORK_SOCKET_SETPRIV,
814 		    so, NULL, NULL))
815 			return EPERM;
816 		break;
817 	}
818 
819 	s = splnet();
820 	error = in6_control1(so , cmd, data, ifp, l);
821 	splx(s);
822 	return error;
823 }
824 
825 /*
826  * Update parameters of an IPv6 interface address.
827  * If necessary, a new entry is created and linked into address chains.
828  * This function is separated from in6_control().
829  * XXX: should this be performed under splnet()?
830  */
831 static int
832 in6_update_ifa1(struct ifnet *ifp, struct in6_aliasreq *ifra,
833     struct in6_ifaddr *ia, int flags)
834 {
835 	int error = 0, hostIsNew = 0, plen = -1;
836 	struct in6_ifaddr *oia;
837 	struct sockaddr_in6 dst6;
838 	struct in6_addrlifetime *lt;
839 	struct in6_multi_mship *imm;
840 	struct in6_multi *in6m_sol;
841 	struct rtentry *rt;
842 	int dad_delay;
843 
844 	in6m_sol = NULL;
845 
846 	/* Validate parameters */
847 	if (ifp == NULL || ifra == NULL) /* this maybe redundant */
848 		return EINVAL;
849 
850 	/*
851 	 * The destination address for a p2p link must have a family
852 	 * of AF_UNSPEC or AF_INET6.
853 	 */
854 	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
855 	    ifra->ifra_dstaddr.sin6_family != AF_INET6 &&
856 	    ifra->ifra_dstaddr.sin6_family != AF_UNSPEC)
857 		return EAFNOSUPPORT;
858 	/*
859 	 * validate ifra_prefixmask.  don't check sin6_family, netmask
860 	 * does not carry fields other than sin6_len.
861 	 */
862 	if (ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6))
863 		return EINVAL;
864 	/*
865 	 * Because the IPv6 address architecture is classless, we require
866 	 * users to specify a (non 0) prefix length (mask) for a new address.
867 	 * We also require the prefix (when specified) mask is valid, and thus
868 	 * reject a non-consecutive mask.
869 	 */
870 	if (ia == NULL && ifra->ifra_prefixmask.sin6_len == 0)
871 		return EINVAL;
872 	if (ifra->ifra_prefixmask.sin6_len != 0) {
873 		plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
874 		    (u_char *)&ifra->ifra_prefixmask +
875 		    ifra->ifra_prefixmask.sin6_len);
876 		if (plen <= 0)
877 			return EINVAL;
878 	} else {
879 		/*
880 		 * In this case, ia must not be NULL.  We just use its prefix
881 		 * length.
882 		 */
883 		plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
884 	}
885 	/*
886 	 * If the destination address on a p2p interface is specified,
887 	 * and the address is a scoped one, validate/set the scope
888 	 * zone identifier.
889 	 */
890 	dst6 = ifra->ifra_dstaddr;
891 	if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) != 0 &&
892 	    (dst6.sin6_family == AF_INET6)) {
893 		struct in6_addr in6_tmp;
894 		u_int32_t zoneid;
895 
896 		in6_tmp = dst6.sin6_addr;
897 		if (in6_setscope(&in6_tmp, ifp, &zoneid))
898 			return EINVAL; /* XXX: should be impossible */
899 
900 		if (dst6.sin6_scope_id != 0) {
901 			if (dst6.sin6_scope_id != zoneid)
902 				return EINVAL;
903 		} else		/* user omit to specify the ID. */
904 			dst6.sin6_scope_id = zoneid;
905 
906 		/* convert into the internal form */
907 		if (sa6_embedscope(&dst6, 0))
908 			return EINVAL; /* XXX: should be impossible */
909 	}
910 	/*
911 	 * The destination address can be specified only for a p2p or a
912 	 * loopback interface.  If specified, the corresponding prefix length
913 	 * must be 128.
914 	 */
915 	if (ifra->ifra_dstaddr.sin6_family == AF_INET6) {
916 #ifdef FORCE_P2PPLEN
917 		int i;
918 #endif
919 
920 		if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) == 0) {
921 			/* XXX: noisy message */
922 			nd6log((LOG_INFO, "in6_update_ifa: a destination can "
923 			    "be specified for a p2p or a loopback IF only\n"));
924 			return EINVAL;
925 		}
926 		if (plen != 128) {
927 			nd6log((LOG_INFO, "in6_update_ifa: prefixlen should "
928 			    "be 128 when dstaddr is specified\n"));
929 #ifdef FORCE_P2PPLEN
930 			/*
931 			 * To be compatible with old configurations,
932 			 * such as ifconfig gif0 inet6 2001::1 2001::2
933 			 * prefixlen 126, we override the specified
934 			 * prefixmask as if the prefix length was 128.
935 			 */
936 			ifra->ifra_prefixmask.sin6_len =
937 			    sizeof(struct sockaddr_in6);
938 			for (i = 0; i < 4; i++)
939 				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i] =
940 				    0xffffffff;
941 			plen = 128;
942 #else
943 			return EINVAL;
944 #endif
945 		}
946 	}
947 	/* lifetime consistency check */
948 	lt = &ifra->ifra_lifetime;
949 	if (lt->ia6t_pltime > lt->ia6t_vltime)
950 		return EINVAL;
951 	if (lt->ia6t_vltime == 0) {
952 		/*
953 		 * the following log might be noisy, but this is a typical
954 		 * configuration mistake or a tool's bug.
955 		 */
956 		nd6log((LOG_INFO,
957 		    "in6_update_ifa: valid lifetime is 0 for %s\n",
958 		    ip6_sprintf(&ifra->ifra_addr.sin6_addr)));
959 
960 		if (ia == NULL)
961 			return 0; /* there's nothing to do */
962 	}
963 
964 	/*
965 	 * If this is a new address, allocate a new ifaddr and link it
966 	 * into chains.
967 	 */
968 	if (ia == NULL) {
969 		hostIsNew = 1;
970 		/*
971 		 * When in6_update_ifa() is called in a process of a received
972 		 * RA, it is called under an interrupt context.  So, we should
973 		 * call malloc with M_NOWAIT.
974 		 */
975 		ia = (struct in6_ifaddr *) malloc(sizeof(*ia), M_IFADDR,
976 		    M_NOWAIT);
977 		if (ia == NULL)
978 			return ENOBUFS;
979 		memset(ia, 0, sizeof(*ia));
980 		LIST_INIT(&ia->ia6_memberships);
981 		/* Initialize the address and masks, and put time stamp */
982 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
983 		ia->ia_addr.sin6_family = AF_INET6;
984 		ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
985 		ia->ia6_createtime = time_second;
986 		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
987 			/*
988 			 * XXX: some functions expect that ifa_dstaddr is not
989 			 * NULL for p2p interfaces.
990 			 */
991 			ia->ia_ifa.ifa_dstaddr =
992 			    (struct sockaddr *)&ia->ia_dstaddr;
993 		} else {
994 			ia->ia_ifa.ifa_dstaddr = NULL;
995 		}
996 		ia->ia_ifa.ifa_netmask =
997 		    (struct sockaddr *)&ia->ia_prefixmask;
998 
999 		ia->ia_ifp = ifp;
1000 		if ((oia = in6_ifaddr) != NULL) {
1001 			for ( ; oia->ia_next; oia = oia->ia_next)
1002 				continue;
1003 			oia->ia_next = ia;
1004 		} else
1005 			in6_ifaddr = ia;
1006 		/* gain a refcnt for the link from in6_ifaddr */
1007 		IFAREF(&ia->ia_ifa);
1008 
1009 		ifa_insert(ifp, &ia->ia_ifa);
1010 	}
1011 
1012 	/* update timestamp */
1013 	ia->ia6_updatetime = time_second;
1014 
1015 	/* set prefix mask */
1016 	if (ifra->ifra_prefixmask.sin6_len) {
1017 		/*
1018 		 * We prohibit changing the prefix length of an existing
1019 		 * address, because
1020 		 * + such an operation should be rare in IPv6, and
1021 		 * + the operation would confuse prefix management.
1022 		 */
1023 		if (ia->ia_prefixmask.sin6_len &&
1024 		    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL) != plen) {
1025 			nd6log((LOG_INFO, "in6_update_ifa: the prefix length of an"
1026 			    " existing (%s) address should not be changed\n",
1027 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1028 			error = EINVAL;
1029 			goto unlink;
1030 		}
1031 		ia->ia_prefixmask = ifra->ifra_prefixmask;
1032 	}
1033 
1034 	/*
1035 	 * If a new destination address is specified, scrub the old one and
1036 	 * install the new destination.  Note that the interface must be
1037 	 * p2p or loopback (see the check above.)
1038 	 */
1039 	if (dst6.sin6_family == AF_INET6 &&
1040 	    !IN6_ARE_ADDR_EQUAL(&dst6.sin6_addr, &ia->ia_dstaddr.sin6_addr)) {
1041 		if ((ia->ia_flags & IFA_ROUTE) != 0 &&
1042 		    rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST) != 0) {
1043 			nd6log((LOG_ERR, "in6_update_ifa: failed to remove "
1044 			    "a route to the old destination: %s\n",
1045 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1046 			/* proceed anyway... */
1047 		} else
1048 			ia->ia_flags &= ~IFA_ROUTE;
1049 		ia->ia_dstaddr = dst6;
1050 	}
1051 
1052 	/*
1053 	 * Set lifetimes.  We do not refer to ia6t_expire and ia6t_preferred
1054 	 * to see if the address is deprecated or invalidated, but initialize
1055 	 * these members for applications.
1056 	 */
1057 	ia->ia6_lifetime = ifra->ifra_lifetime;
1058 	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
1059 		ia->ia6_lifetime.ia6t_expire =
1060 		    time_second + ia->ia6_lifetime.ia6t_vltime;
1061 	} else
1062 		ia->ia6_lifetime.ia6t_expire = 0;
1063 	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
1064 		ia->ia6_lifetime.ia6t_preferred =
1065 		    time_second + ia->ia6_lifetime.ia6t_pltime;
1066 	} else
1067 		ia->ia6_lifetime.ia6t_preferred = 0;
1068 
1069 	/*
1070 	 * configure address flags.
1071 	 */
1072 	ia->ia6_flags = ifra->ifra_flags;
1073 
1074 	/*
1075 	 * Make the address tentative before joining multicast addresses,
1076 	 * so that corresponding MLD responses would not have a tentative
1077 	 * source address.
1078 	 */
1079 	ia->ia6_flags &= ~IN6_IFF_DUPLICATED;	/* safety */
1080 	if (ifp->if_link_state == LINK_STATE_DOWN) {
1081 		ia->ia6_flags |= IN6_IFF_DETACHED;
1082 		ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1083 	} else if (hostIsNew && in6if_do_dad(ifp))
1084 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
1085 
1086 	/*
1087 	 * backward compatibility - if IN6_IFF_DEPRECATED is set from the
1088 	 * userland, make it deprecated.
1089 	 */
1090 	if ((ifra->ifra_flags & IN6_IFF_DEPRECATED) != 0) {
1091 		ia->ia6_lifetime.ia6t_pltime = 0;
1092 		ia->ia6_lifetime.ia6t_preferred = time_second;
1093 	}
1094 
1095 	/* reset the interface and routing table appropriately. */
1096 	if ((error = in6_ifinit(ifp, ia, &ifra->ifra_addr, hostIsNew)) != 0)
1097 		goto unlink;
1098 	/*
1099 	 * We are done if we have simply modified an existing address.
1100 	 */
1101 	if (!hostIsNew)
1102 		return error;
1103 
1104 	/*
1105 	 * Beyond this point, we should call in6_purgeaddr upon an error,
1106 	 * not just go to unlink.
1107 	 */
1108 
1109 	/* join necessary multicast groups */
1110 	if ((ifp->if_flags & IFF_MULTICAST) != 0) {
1111 		struct sockaddr_in6 mltaddr, mltmask;
1112 		struct in6_addr llsol;
1113 
1114 		/* join solicited multicast addr for new host id */
1115 		memset(&llsol, 0, sizeof(struct in6_addr));
1116 		llsol.s6_addr16[0] = htons(0xff02);
1117 		llsol.s6_addr32[1] = 0;
1118 		llsol.s6_addr32[2] = htonl(1);
1119 		llsol.s6_addr32[3] = ifra->ifra_addr.sin6_addr.s6_addr32[3];
1120 		llsol.s6_addr8[12] = 0xff;
1121 		if ((error = in6_setscope(&llsol, ifp, NULL)) != 0) {
1122 			/* XXX: should not happen */
1123 			log(LOG_ERR, "in6_update_ifa: "
1124 			    "in6_setscope failed\n");
1125 			goto cleanup;
1126 		}
1127 		dad_delay = 0;
1128 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1129 			/*
1130 			 * We need a random delay for DAD on the address
1131 			 * being configured.  It also means delaying
1132 			 * transmission of the corresponding MLD report to
1133 			 * avoid report collision.
1134 			 * [draft-ietf-ipv6-rfc2462bis-02.txt]
1135 			 */
1136 			dad_delay = cprng_fast32() %
1137 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1138 		}
1139 
1140 #define	MLTMASK_LEN  4	/* mltmask's masklen (=32bit=4octet) */
1141 		/* join solicited multicast addr for new host id */
1142 		imm = in6_joingroup(ifp, &llsol, &error, dad_delay);
1143 		if (!imm) {
1144 			nd6log((LOG_ERR,
1145 			    "in6_update_ifa: addmulti "
1146 			    "failed for %s on %s (errno=%d)\n",
1147 			    ip6_sprintf(&llsol), if_name(ifp), error));
1148 			goto cleanup;
1149 		}
1150 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1151 		in6m_sol = imm->i6mm_maddr;
1152 
1153 		sockaddr_in6_init(&mltmask, &in6mask32, 0, 0, 0);
1154 
1155 		/*
1156 		 * join link-local all-nodes address
1157 		 */
1158 		sockaddr_in6_init(&mltaddr, &in6addr_linklocal_allnodes,
1159 		    0, 0, 0);
1160 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1161 			goto cleanup; /* XXX: should not fail */
1162 
1163 		/*
1164 		 * XXX: do we really need this automatic routes?
1165 		 * We should probably reconsider this stuff.  Most applications
1166 		 * actually do not need the routes, since they usually specify
1167 		 * the outgoing interface.
1168 		 */
1169 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1170 		if (rt) {
1171 			if (memcmp(&mltaddr.sin6_addr,
1172 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1173 			    MLTMASK_LEN)) {
1174 				RTFREE(rt);
1175 				rt = NULL;
1176 			} else if (rt->rt_ifp != ifp) {
1177 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1178 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1179 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1180 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1181 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1182 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1183 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1184 				rt_replace_ifa(rt, &ia->ia_ifa);
1185 				rt->rt_ifp = ifp;
1186 			}
1187 		}
1188 		if (!rt) {
1189 			struct rt_addrinfo info;
1190 
1191 			memset(&info, 0, sizeof(info));
1192 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1193 			info.rti_info[RTAX_GATEWAY] =
1194 			    (struct sockaddr *)&ia->ia_addr;
1195 			info.rti_info[RTAX_NETMASK] =
1196 			    (struct sockaddr *)&mltmask;
1197 			info.rti_info[RTAX_IFA] =
1198 			    (struct sockaddr *)&ia->ia_addr;
1199 			/* XXX: we need RTF_CLONING to fake nd6_rtrequest */
1200 			info.rti_flags = RTF_UP | RTF_CLONING;
1201 			error = rtrequest1(RTM_ADD, &info, NULL);
1202 			if (error)
1203 				goto cleanup;
1204 		} else {
1205 			RTFREE(rt);
1206 		}
1207 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1208 		if (!imm) {
1209 			nd6log((LOG_WARNING,
1210 			    "in6_update_ifa: addmulti failed for "
1211 			    "%s on %s (errno=%d)\n",
1212 			    ip6_sprintf(&mltaddr.sin6_addr),
1213 			    if_name(ifp), error));
1214 			goto cleanup;
1215 		}
1216 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1217 
1218 		/*
1219 		 * join node information group address
1220 		 */
1221 		dad_delay = 0;
1222 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1223 			/*
1224 			 * The spec doesn't say anything about delay for this
1225 			 * group, but the same logic should apply.
1226 			 */
1227 			dad_delay = cprng_fast32() %
1228 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1229 		}
1230 		if (in6_nigroup(ifp, hostname, hostnamelen, &mltaddr) != 0)
1231 			;
1232 		else if ((imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error,
1233 		          dad_delay)) == NULL) { /* XXX jinmei */
1234 			nd6log((LOG_WARNING, "in6_update_ifa: "
1235 			    "addmulti failed for %s on %s (errno=%d)\n",
1236 			    ip6_sprintf(&mltaddr.sin6_addr),
1237 			    if_name(ifp), error));
1238 			/* XXX not very fatal, go on... */
1239 		} else {
1240 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1241 		}
1242 
1243 
1244 		/*
1245 		 * join interface-local all-nodes address.
1246 		 * (ff01::1%ifN, and ff01::%ifN/32)
1247 		 */
1248 		mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
1249 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1250 			goto cleanup; /* XXX: should not fail */
1251 
1252 		/* XXX: again, do we really need the route? */
1253 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1254 		if (rt) {
1255 			/* 32bit came from "mltmask" */
1256 			if (memcmp(&mltaddr.sin6_addr,
1257 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1258 			    32 / NBBY)) {
1259 				RTFREE(rt);
1260 				rt = NULL;
1261 			} else if (rt->rt_ifp != ifp) {
1262 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1263 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1264 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1265 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1266 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1267 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1268 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1269 				rt_replace_ifa(rt, &ia->ia_ifa);
1270 				rt->rt_ifp = ifp;
1271 			}
1272 		}
1273 		if (!rt) {
1274 			struct rt_addrinfo info;
1275 
1276 			memset(&info, 0, sizeof(info));
1277 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1278 			info.rti_info[RTAX_GATEWAY] =
1279 			    (struct sockaddr *)&ia->ia_addr;
1280 			info.rti_info[RTAX_NETMASK] =
1281 			    (struct sockaddr *)&mltmask;
1282 			info.rti_info[RTAX_IFA] =
1283 			    (struct sockaddr *)&ia->ia_addr;
1284 			info.rti_flags = RTF_UP | RTF_CLONING;
1285 			error = rtrequest1(RTM_ADD, &info, NULL);
1286 			if (error)
1287 				goto cleanup;
1288 #undef	MLTMASK_LEN
1289 		} else {
1290 			RTFREE(rt);
1291 		}
1292 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1293 		if (!imm) {
1294 			nd6log((LOG_WARNING, "in6_update_ifa: "
1295 			    "addmulti failed for %s on %s (errno=%d)\n",
1296 			    ip6_sprintf(&mltaddr.sin6_addr),
1297 			    if_name(ifp), error));
1298 			goto cleanup;
1299 		} else {
1300 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1301 		}
1302 	}
1303 
1304 	/*
1305 	 * Perform DAD, if needed.
1306 	 * XXX It may be of use, if we can administratively
1307 	 * disable DAD.
1308 	 */
1309 	if (hostIsNew && in6if_do_dad(ifp) &&
1310 	    ((ifra->ifra_flags & IN6_IFF_NODAD) == 0) &&
1311 	    (ia->ia6_flags & IN6_IFF_TENTATIVE))
1312 	{
1313 		int mindelay, maxdelay;
1314 
1315 		dad_delay = 0;
1316 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1317 			/*
1318 			 * We need to impose a delay before sending an NS
1319 			 * for DAD.  Check if we also needed a delay for the
1320 			 * corresponding MLD message.  If we did, the delay
1321 			 * should be larger than the MLD delay (this could be
1322 			 * relaxed a bit, but this simple logic is at least
1323 			 * safe).
1324 			 */
1325 			mindelay = 0;
1326 			if (in6m_sol != NULL &&
1327 			    in6m_sol->in6m_state == MLD_REPORTPENDING) {
1328 				mindelay = in6m_sol->in6m_timer;
1329 			}
1330 			maxdelay = MAX_RTR_SOLICITATION_DELAY * hz;
1331 			if (maxdelay - mindelay == 0)
1332 				dad_delay = 0;
1333 			else {
1334 				dad_delay =
1335 				    (cprng_fast32() % (maxdelay - mindelay)) +
1336 				    mindelay;
1337 			}
1338 		}
1339 		nd6_dad_start(&ia->ia_ifa, dad_delay);
1340 	}
1341 
1342 	return error;
1343 
1344   unlink:
1345 	/*
1346 	 * XXX: if a change of an existing address failed, keep the entry
1347 	 * anyway.
1348 	 */
1349 	if (hostIsNew)
1350 		in6_unlink_ifa(ia, ifp);
1351 	return error;
1352 
1353   cleanup:
1354 	in6_purgeaddr(&ia->ia_ifa);
1355 	return error;
1356 }
1357 
1358 int
1359 in6_update_ifa(struct ifnet *ifp, struct in6_aliasreq *ifra,
1360     struct in6_ifaddr *ia, int flags)
1361 {
1362 	int rc, s;
1363 
1364 	s = splnet();
1365 	rc = in6_update_ifa1(ifp, ifra, ia, flags);
1366 	splx(s);
1367 	return rc;
1368 }
1369 
1370 void
1371 in6_purgeaddr(struct ifaddr *ifa)
1372 {
1373 	struct ifnet *ifp = ifa->ifa_ifp;
1374 	struct in6_ifaddr *ia = (struct in6_ifaddr *) ifa;
1375 	struct in6_multi_mship *imm;
1376 
1377 	/* stop DAD processing */
1378 	nd6_dad_stop(ifa);
1379 
1380 	/*
1381 	 * delete route to the destination of the address being purged.
1382 	 * The interface must be p2p or loopback in this case.
1383 	 */
1384 	if ((ia->ia_flags & IFA_ROUTE) != 0 && ia->ia_dstaddr.sin6_len != 0) {
1385 		int e;
1386 
1387 		if ((e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
1388 		    != 0) {
1389 			log(LOG_ERR, "in6_purgeaddr: failed to remove "
1390 			    "a route to the p2p destination: %s on %s, "
1391 			    "errno=%d\n",
1392 			    ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
1393 			    e);
1394 			/* proceed anyway... */
1395 		} else
1396 			ia->ia_flags &= ~IFA_ROUTE;
1397 	}
1398 
1399 	/* Remove ownaddr's loopback rtentry, if it exists. */
1400 	in6_ifremloop(&(ia->ia_ifa));
1401 
1402 	/*
1403 	 * leave from multicast groups we have joined for the interface
1404 	 */
1405 	while ((imm = LIST_FIRST(&ia->ia6_memberships)) != NULL) {
1406 		LIST_REMOVE(imm, i6mm_chain);
1407 		in6_leavegroup(imm);
1408 	}
1409 
1410 	in6_unlink_ifa(ia, ifp);
1411 }
1412 
1413 static void
1414 in6_unlink_ifa(struct in6_ifaddr *ia, struct ifnet *ifp)
1415 {
1416 	struct in6_ifaddr *oia;
1417 	int	s = splnet();
1418 
1419 	ifa_remove(ifp, &ia->ia_ifa);
1420 
1421 	oia = ia;
1422 	if (oia == (ia = in6_ifaddr))
1423 		in6_ifaddr = ia->ia_next;
1424 	else {
1425 		while (ia->ia_next && (ia->ia_next != oia))
1426 			ia = ia->ia_next;
1427 		if (ia->ia_next)
1428 			ia->ia_next = oia->ia_next;
1429 		else {
1430 			/* search failed */
1431 			printf("Couldn't unlink in6_ifaddr from in6_ifaddr\n");
1432 		}
1433 	}
1434 
1435 	/*
1436 	 * XXX thorpej@NetBSD.org -- if the interface is going
1437 	 * XXX away, don't save the multicast entries, delete them!
1438 	 */
1439 	if (LIST_EMPTY(&oia->ia6_multiaddrs))
1440 		;
1441 	else if (oia->ia_ifa.ifa_ifp->if_output == if_nulloutput) {
1442 		struct in6_multi *in6m, *next;
1443 
1444 		for (in6m = LIST_FIRST(&oia->ia6_multiaddrs); in6m != NULL;
1445 		     in6m = next) {
1446 			next = LIST_NEXT(in6m, in6m_entry);
1447 			in6_delmulti(in6m);
1448 		}
1449 	} else
1450 		in6_savemkludge(oia);
1451 
1452 	/*
1453 	 * Release the reference to the base prefix.  There should be a
1454 	 * positive reference.
1455 	 */
1456 	if (oia->ia6_ndpr == NULL) {
1457 		nd6log((LOG_NOTICE, "in6_unlink_ifa: autoconf'ed address "
1458 		    "%p has no prefix\n", oia));
1459 	} else {
1460 		oia->ia6_ndpr->ndpr_refcnt--;
1461 		oia->ia6_ndpr = NULL;
1462 	}
1463 
1464 	/*
1465 	 * Also, if the address being removed is autoconf'ed, call
1466 	 * pfxlist_onlink_check() since the release might affect the status of
1467 	 * other (detached) addresses.
1468 	 */
1469 	if ((oia->ia6_flags & IN6_IFF_AUTOCONF) != 0)
1470 		pfxlist_onlink_check();
1471 
1472 	/*
1473 	 * release another refcnt for the link from in6_ifaddr.
1474 	 * Note that we should decrement the refcnt at least once for all *BSD.
1475 	 */
1476 	IFAFREE(&oia->ia_ifa);
1477 
1478 	splx(s);
1479 }
1480 
1481 void
1482 in6_purgeif(struct ifnet *ifp)
1483 {
1484 	if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr);
1485 
1486 	in6_ifdetach(ifp);
1487 }
1488 
1489 /*
1490  * SIOC[GAD]LIFADDR.
1491  *	SIOCGLIFADDR: get first address. (?)
1492  *	SIOCGLIFADDR with IFLR_PREFIX:
1493  *		get first address that matches the specified prefix.
1494  *	SIOCALIFADDR: add the specified address.
1495  *	SIOCALIFADDR with IFLR_PREFIX:
1496  *		add the specified prefix, filling hostid part from
1497  *		the first link-local address.  prefixlen must be <= 64.
1498  *	SIOCDLIFADDR: delete the specified address.
1499  *	SIOCDLIFADDR with IFLR_PREFIX:
1500  *		delete the first address that matches the specified prefix.
1501  * return values:
1502  *	EINVAL on invalid parameters
1503  *	EADDRNOTAVAIL on prefix match failed/specified address not found
1504  *	other values may be returned from in6_ioctl()
1505  *
1506  * NOTE: SIOCALIFADDR(with IFLR_PREFIX set) allows prefixlen less than 64.
1507  * this is to accommodate address naming scheme other than RFC2374,
1508  * in the future.
1509  * RFC2373 defines interface id to be 64bit, but it allows non-RFC2374
1510  * address encoding scheme. (see figure on page 8)
1511  */
1512 static int
1513 in6_lifaddr_ioctl(struct socket *so, u_long cmd, void *data,
1514 	struct ifnet *ifp, struct lwp *l)
1515 {
1516 	struct in6_ifaddr *ia;
1517 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
1518 	struct ifaddr *ifa;
1519 	struct sockaddr *sa;
1520 
1521 	/* sanity checks */
1522 	if (!data || !ifp) {
1523 		panic("invalid argument to in6_lifaddr_ioctl");
1524 		/* NOTREACHED */
1525 	}
1526 
1527 	switch (cmd) {
1528 	case SIOCGLIFADDR:
1529 		/* address must be specified on GET with IFLR_PREFIX */
1530 		if ((iflr->flags & IFLR_PREFIX) == 0)
1531 			break;
1532 		/* FALLTHROUGH */
1533 	case SIOCALIFADDR:
1534 	case SIOCDLIFADDR:
1535 		/* address must be specified on ADD and DELETE */
1536 		sa = (struct sockaddr *)&iflr->addr;
1537 		if (sa->sa_family != AF_INET6)
1538 			return EINVAL;
1539 		if (sa->sa_len != sizeof(struct sockaddr_in6))
1540 			return EINVAL;
1541 		/* XXX need improvement */
1542 		sa = (struct sockaddr *)&iflr->dstaddr;
1543 		if (sa->sa_family && sa->sa_family != AF_INET6)
1544 			return EINVAL;
1545 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in6))
1546 			return EINVAL;
1547 		break;
1548 	default: /* shouldn't happen */
1549 #if 0
1550 		panic("invalid cmd to in6_lifaddr_ioctl");
1551 		/* NOTREACHED */
1552 #else
1553 		return EOPNOTSUPP;
1554 #endif
1555 	}
1556 	if (sizeof(struct in6_addr) * NBBY < iflr->prefixlen)
1557 		return EINVAL;
1558 
1559 	switch (cmd) {
1560 	case SIOCALIFADDR:
1561 	    {
1562 		struct in6_aliasreq ifra;
1563 		struct in6_addr *xhostid = NULL;
1564 		int prefixlen;
1565 
1566 		if ((iflr->flags & IFLR_PREFIX) != 0) {
1567 			struct sockaddr_in6 *sin6;
1568 
1569 			/*
1570 			 * xhostid is to fill in the hostid part of the
1571 			 * address.  xhostid points to the first link-local
1572 			 * address attached to the interface.
1573 			 */
1574 			ia = in6ifa_ifpforlinklocal(ifp, 0);
1575 			if (ia == NULL)
1576 				return EADDRNOTAVAIL;
1577 			xhostid = IFA_IN6(&ia->ia_ifa);
1578 
1579 		 	/* prefixlen must be <= 64. */
1580 			if (64 < iflr->prefixlen)
1581 				return EINVAL;
1582 			prefixlen = iflr->prefixlen;
1583 
1584 			/* hostid part must be zero. */
1585 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1586 			if (sin6->sin6_addr.s6_addr32[2] != 0
1587 			 || sin6->sin6_addr.s6_addr32[3] != 0) {
1588 				return EINVAL;
1589 			}
1590 		} else
1591 			prefixlen = iflr->prefixlen;
1592 
1593 		/* copy args to in6_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
1594 		memset(&ifra, 0, sizeof(ifra));
1595 		memcpy(ifra.ifra_name, iflr->iflr_name, sizeof(ifra.ifra_name));
1596 
1597 		memcpy(&ifra.ifra_addr, &iflr->addr,
1598 		    ((struct sockaddr *)&iflr->addr)->sa_len);
1599 		if (xhostid) {
1600 			/* fill in hostid part */
1601 			ifra.ifra_addr.sin6_addr.s6_addr32[2] =
1602 			    xhostid->s6_addr32[2];
1603 			ifra.ifra_addr.sin6_addr.s6_addr32[3] =
1604 			    xhostid->s6_addr32[3];
1605 		}
1606 
1607 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) { /* XXX */
1608 			memcpy(&ifra.ifra_dstaddr, &iflr->dstaddr,
1609 			    ((struct sockaddr *)&iflr->dstaddr)->sa_len);
1610 			if (xhostid) {
1611 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[2] =
1612 				    xhostid->s6_addr32[2];
1613 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[3] =
1614 				    xhostid->s6_addr32[3];
1615 			}
1616 		}
1617 
1618 		ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
1619 		in6_prefixlen2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);
1620 
1621 		ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
1622 		ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
1623 		ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
1624 		return in6_control(so, SIOCAIFADDR_IN6, &ifra, ifp, l);
1625 	    }
1626 	case SIOCGLIFADDR:
1627 	case SIOCDLIFADDR:
1628 	    {
1629 		struct in6_addr mask, candidate, match;
1630 		struct sockaddr_in6 *sin6;
1631 		int cmp;
1632 
1633 		memset(&mask, 0, sizeof(mask));
1634 		if (iflr->flags & IFLR_PREFIX) {
1635 			/* lookup a prefix rather than address. */
1636 			in6_prefixlen2mask(&mask, iflr->prefixlen);
1637 
1638 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1639 			memcpy(&match, &sin6->sin6_addr, sizeof(match));
1640 			match.s6_addr32[0] &= mask.s6_addr32[0];
1641 			match.s6_addr32[1] &= mask.s6_addr32[1];
1642 			match.s6_addr32[2] &= mask.s6_addr32[2];
1643 			match.s6_addr32[3] &= mask.s6_addr32[3];
1644 
1645 			/* if you set extra bits, that's wrong */
1646 			if (memcmp(&match, &sin6->sin6_addr, sizeof(match)))
1647 				return EINVAL;
1648 
1649 			cmp = 1;
1650 		} else {
1651 			if (cmd == SIOCGLIFADDR) {
1652 				/* on getting an address, take the 1st match */
1653 				cmp = 0;	/* XXX */
1654 			} else {
1655 				/* on deleting an address, do exact match */
1656 				in6_prefixlen2mask(&mask, 128);
1657 				sin6 = (struct sockaddr_in6 *)&iflr->addr;
1658 				memcpy(&match, &sin6->sin6_addr, sizeof(match));
1659 
1660 				cmp = 1;
1661 			}
1662 		}
1663 
1664 		IFADDR_FOREACH(ifa, ifp) {
1665 			if (ifa->ifa_addr->sa_family != AF_INET6)
1666 				continue;
1667 			if (!cmp)
1668 				break;
1669 
1670 			/*
1671 			 * XXX: this is adhoc, but is necessary to allow
1672 			 * a user to specify fe80::/64 (not /10) for a
1673 			 * link-local address.
1674 			 */
1675 			memcpy(&candidate, IFA_IN6(ifa), sizeof(candidate));
1676 			in6_clearscope(&candidate);
1677 			candidate.s6_addr32[0] &= mask.s6_addr32[0];
1678 			candidate.s6_addr32[1] &= mask.s6_addr32[1];
1679 			candidate.s6_addr32[2] &= mask.s6_addr32[2];
1680 			candidate.s6_addr32[3] &= mask.s6_addr32[3];
1681 			if (IN6_ARE_ADDR_EQUAL(&candidate, &match))
1682 				break;
1683 		}
1684 		if (!ifa)
1685 			return EADDRNOTAVAIL;
1686 		ia = ifa2ia6(ifa);
1687 
1688 		if (cmd == SIOCGLIFADDR) {
1689 			int error;
1690 
1691 			/* fill in the if_laddrreq structure */
1692 			memcpy(&iflr->addr, &ia->ia_addr, ia->ia_addr.sin6_len);
1693 			error = sa6_recoverscope(
1694 			    (struct sockaddr_in6 *)&iflr->addr);
1695 			if (error != 0)
1696 				return error;
1697 
1698 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1699 				memcpy(&iflr->dstaddr, &ia->ia_dstaddr,
1700 				    ia->ia_dstaddr.sin6_len);
1701 				error = sa6_recoverscope(
1702 				    (struct sockaddr_in6 *)&iflr->dstaddr);
1703 				if (error != 0)
1704 					return error;
1705 			} else
1706 				memset(&iflr->dstaddr, 0, sizeof(iflr->dstaddr));
1707 
1708 			iflr->prefixlen =
1709 			    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
1710 
1711 			iflr->flags = ia->ia6_flags;	/* XXX */
1712 
1713 			return 0;
1714 		} else {
1715 			struct in6_aliasreq ifra;
1716 
1717 			/* fill in6_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
1718 			memset(&ifra, 0, sizeof(ifra));
1719 			memcpy(ifra.ifra_name, iflr->iflr_name,
1720 			    sizeof(ifra.ifra_name));
1721 
1722 			memcpy(&ifra.ifra_addr, &ia->ia_addr,
1723 			    ia->ia_addr.sin6_len);
1724 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1725 				memcpy(&ifra.ifra_dstaddr, &ia->ia_dstaddr,
1726 				    ia->ia_dstaddr.sin6_len);
1727 			} else {
1728 				memset(&ifra.ifra_dstaddr, 0,
1729 				    sizeof(ifra.ifra_dstaddr));
1730 			}
1731 			memcpy(&ifra.ifra_dstaddr, &ia->ia_prefixmask,
1732 			    ia->ia_prefixmask.sin6_len);
1733 
1734 			ifra.ifra_flags = ia->ia6_flags;
1735 			return in6_control(so, SIOCDIFADDR_IN6, &ifra, ifp, l);
1736 		}
1737 	    }
1738 	}
1739 
1740 	return EOPNOTSUPP;	/* just for safety */
1741 }
1742 
1743 /*
1744  * Initialize an interface's internet6 address
1745  * and routing table entry.
1746  */
1747 static int
1748 in6_ifinit(struct ifnet *ifp, struct in6_ifaddr *ia,
1749 	const struct sockaddr_in6 *sin6, int newhost)
1750 {
1751 	int	error = 0, plen, ifacount = 0;
1752 	int	s = splnet();
1753 	struct ifaddr *ifa;
1754 
1755 	/*
1756 	 * Give the interface a chance to initialize
1757 	 * if this is its first address,
1758 	 * and to validate the address if necessary.
1759 	 */
1760 	IFADDR_FOREACH(ifa, ifp) {
1761 		if (ifa->ifa_addr == NULL)
1762 			continue;	/* just for safety */
1763 		if (ifa->ifa_addr->sa_family != AF_INET6)
1764 			continue;
1765 		ifacount++;
1766 	}
1767 
1768 	ia->ia_addr = *sin6;
1769 
1770 	if (ifacount <= 1 &&
1771 	    (error = if_addr_init(ifp, &ia->ia_ifa, true)) != 0) {
1772 		splx(s);
1773 		return error;
1774 	}
1775 	splx(s);
1776 
1777 	ia->ia_ifa.ifa_metric = ifp->if_metric;
1778 
1779 	/* we could do in(6)_socktrim here, but just omit it at this moment. */
1780 
1781 	/*
1782 	 * Special case:
1783 	 * If the destination address is specified for a point-to-point
1784 	 * interface, install a route to the destination as an interface
1785 	 * direct route.
1786 	 */
1787 	plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
1788 	if (plen == 128 && ia->ia_dstaddr.sin6_family == AF_INET6) {
1789 		if ((error = rtinit(&ia->ia_ifa, RTM_ADD,
1790 				    RTF_UP | RTF_HOST)) != 0)
1791 			return error;
1792 		ia->ia_flags |= IFA_ROUTE;
1793 	}
1794 
1795 	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
1796 	if (newhost) {
1797 		/* set the rtrequest function to create llinfo */
1798 		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
1799 		in6_ifaddloop(&ia->ia_ifa);
1800 	} else {
1801 		/* Inform the routing socket of new flags/timings */
1802 		nd6_newaddrmsg(&ia->ia_ifa);
1803 	}
1804 
1805 	if (ifp->if_flags & IFF_MULTICAST)
1806 		in6_restoremkludge(ia, ifp);
1807 
1808 	return error;
1809 }
1810 
1811 static struct ifaddr *
1812 bestifa(struct ifaddr *best_ifa, struct ifaddr *ifa)
1813 {
1814 	if (best_ifa == NULL || best_ifa->ifa_preference < ifa->ifa_preference)
1815 		return ifa;
1816 	return best_ifa;
1817 }
1818 
1819 /*
1820  * Find an IPv6 interface link-local address specific to an interface.
1821  */
1822 struct in6_ifaddr *
1823 in6ifa_ifpforlinklocal(const struct ifnet *ifp, const int ignoreflags)
1824 {
1825 	struct ifaddr *best_ifa = NULL, *ifa;
1826 
1827 	IFADDR_FOREACH(ifa, ifp) {
1828 		if (ifa->ifa_addr == NULL)
1829 			continue;	/* just for safety */
1830 		if (ifa->ifa_addr->sa_family != AF_INET6)
1831 			continue;
1832 		if (!IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa)))
1833 			continue;
1834 		if ((((struct in6_ifaddr *)ifa)->ia6_flags & ignoreflags) != 0)
1835 			continue;
1836 		best_ifa = bestifa(best_ifa, ifa);
1837 	}
1838 
1839 	return (struct in6_ifaddr *)best_ifa;
1840 }
1841 
1842 
1843 /*
1844  * find the internet address corresponding to a given interface and address.
1845  */
1846 struct in6_ifaddr *
1847 in6ifa_ifpwithaddr(const struct ifnet *ifp, const struct in6_addr *addr)
1848 {
1849 	struct ifaddr *best_ifa = NULL, *ifa;
1850 
1851 	IFADDR_FOREACH(ifa, ifp) {
1852 		if (ifa->ifa_addr == NULL)
1853 			continue;	/* just for safety */
1854 		if (ifa->ifa_addr->sa_family != AF_INET6)
1855 			continue;
1856 		if (!IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa)))
1857 			continue;
1858 		best_ifa = bestifa(best_ifa, ifa);
1859 	}
1860 
1861 	return (struct in6_ifaddr *)best_ifa;
1862 }
1863 
1864 static struct in6_ifaddr *
1865 bestia(struct in6_ifaddr *best_ia, struct in6_ifaddr *ia)
1866 {
1867 	if (best_ia == NULL ||
1868 	    best_ia->ia_ifa.ifa_preference < ia->ia_ifa.ifa_preference)
1869 		return ia;
1870 	return best_ia;
1871 }
1872 
1873 /*
1874  * find the internet address on a given interface corresponding to a neighbor's
1875  * address.
1876  */
1877 struct in6_ifaddr *
1878 in6ifa_ifplocaladdr(const struct ifnet *ifp, const struct in6_addr *addr)
1879 {
1880 	struct ifaddr *ifa;
1881 	struct in6_ifaddr *best_ia = NULL, *ia;
1882 
1883 	IFADDR_FOREACH(ifa, ifp) {
1884 		if (ifa->ifa_addr == NULL)
1885 			continue;	/* just for safety */
1886 		if (ifa->ifa_addr->sa_family != AF_INET6)
1887 			continue;
1888 		ia = (struct in6_ifaddr *)ifa;
1889 		if (!IN6_ARE_MASKED_ADDR_EQUAL(addr,
1890 				&ia->ia_addr.sin6_addr,
1891 				&ia->ia_prefixmask.sin6_addr))
1892 			continue;
1893 		best_ia = bestia(best_ia, ia);
1894 	}
1895 
1896 	return best_ia;
1897 }
1898 
1899 /*
1900  * Convert IP6 address to printable (loggable) representation.
1901  */
1902 static int ip6round = 0;
1903 char *
1904 ip6_sprintf(const struct in6_addr *addr)
1905 {
1906 	static char ip6buf[8][48];
1907 	int i;
1908 	char *bp;
1909 	char *cp;
1910 	const u_int16_t *a = (const u_int16_t *)addr;
1911 	const u_int8_t *d;
1912 	int dcolon = 0;
1913 
1914 	ip6round = (ip6round + 1) & 7;
1915 	cp = ip6buf[ip6round];
1916 
1917 	for (i = 0; i < 8; i++) {
1918 		if (dcolon == 1) {
1919 			if (*a == 0) {
1920 				if (i == 7)
1921 					*cp++ = ':';
1922 				a++;
1923 				continue;
1924 			} else
1925 				dcolon = 2;
1926 		}
1927 		if (*a == 0) {
1928 			if (dcolon == 0 && *(a + 1) == 0) {
1929 				if (i == 0)
1930 					*cp++ = ':';
1931 				*cp++ = ':';
1932 				dcolon = 1;
1933 			} else {
1934 				*cp++ = '0';
1935 				*cp++ = ':';
1936 			}
1937 			a++;
1938 			continue;
1939 		}
1940 		d = (const u_char *)a;
1941 		bp = cp;
1942 		*cp = hexdigits[*d >> 4];
1943 		if (*cp != '0')
1944 			cp++;
1945 		*cp = hexdigits[*d++ & 0xf];
1946 		if (cp != bp || *cp != '0')
1947 			cp++;
1948 		*cp = hexdigits[*d >> 4];
1949 		if (cp != bp || *cp != '0')
1950 			cp++;
1951 		*cp++ = hexdigits[*d & 0xf];
1952 		*cp++ = ':';
1953 		a++;
1954 	}
1955 	*--cp = 0;
1956 	return ip6buf[ip6round];
1957 }
1958 
1959 /*
1960  * Determine if an address is on a local network.
1961  */
1962 int
1963 in6_localaddr(const struct in6_addr *in6)
1964 {
1965 	struct in6_ifaddr *ia;
1966 
1967 	if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6))
1968 		return 1;
1969 
1970 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
1971 		if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
1972 					      &ia->ia_prefixmask.sin6_addr))
1973 			return 1;
1974 
1975 	return 0;
1976 }
1977 
1978 int
1979 in6_is_addr_deprecated(struct sockaddr_in6 *sa6)
1980 {
1981 	struct in6_ifaddr *ia;
1982 
1983 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1984 		if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
1985 		    &sa6->sin6_addr) &&
1986 #ifdef SCOPEDROUTING
1987 		    ia->ia_addr.sin6_scope_id == sa6->sin6_scope_id &&
1988 #endif
1989 		    (ia->ia6_flags & IN6_IFF_DEPRECATED) != 0)
1990 			return 1; /* true */
1991 
1992 		/* XXX: do we still have to go thru the rest of the list? */
1993 	}
1994 
1995 	return 0;		/* false */
1996 }
1997 
1998 /*
1999  * return length of part which dst and src are equal
2000  * hard coding...
2001  */
2002 int
2003 in6_matchlen(struct in6_addr *src, struct in6_addr *dst)
2004 {
2005 	int match = 0;
2006 	u_char *s = (u_char *)src, *d = (u_char *)dst;
2007 	u_char *lim = s + 16, r;
2008 
2009 	while (s < lim)
2010 		if ((r = (*d++ ^ *s++)) != 0) {
2011 			while (r < 128) {
2012 				match++;
2013 				r <<= 1;
2014 			}
2015 			break;
2016 		} else
2017 			match += NBBY;
2018 	return match;
2019 }
2020 
2021 /* XXX: to be scope conscious */
2022 int
2023 in6_are_prefix_equal(struct in6_addr *p1, struct in6_addr *p2, int len)
2024 {
2025 	int bytelen, bitlen;
2026 
2027 	/* sanity check */
2028 	if (len < 0 || len > 128) {
2029 		log(LOG_ERR, "in6_are_prefix_equal: invalid prefix length(%d)\n",
2030 		    len);
2031 		return 0;
2032 	}
2033 
2034 	bytelen = len / NBBY;
2035 	bitlen = len % NBBY;
2036 
2037 	if (memcmp(&p1->s6_addr, &p2->s6_addr, bytelen))
2038 		return 0;
2039 	if (bitlen != 0 &&
2040 	    p1->s6_addr[bytelen] >> (NBBY - bitlen) !=
2041 	    p2->s6_addr[bytelen] >> (NBBY - bitlen))
2042 		return 0;
2043 
2044 	return 1;
2045 }
2046 
2047 void
2048 in6_prefixlen2mask(struct in6_addr *maskp, int len)
2049 {
2050 	static const u_char maskarray[NBBY] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
2051 	int bytelen, bitlen, i;
2052 
2053 	/* sanity check */
2054 	if (len < 0 || len > 128) {
2055 		log(LOG_ERR, "in6_prefixlen2mask: invalid prefix length(%d)\n",
2056 		    len);
2057 		return;
2058 	}
2059 
2060 	memset(maskp, 0, sizeof(*maskp));
2061 	bytelen = len / NBBY;
2062 	bitlen = len % NBBY;
2063 	for (i = 0; i < bytelen; i++)
2064 		maskp->s6_addr[i] = 0xff;
2065 	if (bitlen)
2066 		maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
2067 }
2068 
2069 /*
2070  * return the best address out of the same scope. if no address was
2071  * found, return the first valid address from designated IF.
2072  */
2073 struct in6_ifaddr *
2074 in6_ifawithifp(struct ifnet *ifp, struct in6_addr *dst)
2075 {
2076 	int dst_scope =	in6_addrscope(dst), blen = -1, tlen;
2077 	struct ifaddr *ifa;
2078 	struct in6_ifaddr *best_ia = NULL, *ia;
2079 	struct in6_ifaddr *dep[2];	/* last-resort: deprecated */
2080 
2081 	dep[0] = dep[1] = NULL;
2082 
2083 	/*
2084 	 * We first look for addresses in the same scope.
2085 	 * If there is one, return it.
2086 	 * If two or more, return one which matches the dst longest.
2087 	 * If none, return one of global addresses assigned other ifs.
2088 	 */
2089 	IFADDR_FOREACH(ifa, ifp) {
2090 		if (ifa->ifa_addr->sa_family != AF_INET6)
2091 			continue;
2092 		ia = (struct in6_ifaddr *)ifa;
2093 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2094 			continue; /* XXX: is there any case to allow anycast? */
2095 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2096 			continue; /* don't use this interface */
2097 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2098 			continue;
2099 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2100 			if (ip6_use_deprecated)
2101 				dep[0] = ia;
2102 			continue;
2103 		}
2104 
2105 		if (dst_scope != in6_addrscope(IFA_IN6(ifa)))
2106 			continue;
2107 		/*
2108 		 * call in6_matchlen() as few as possible
2109 		 */
2110 		if (best_ia == NULL) {
2111 			best_ia = ia;
2112 			continue;
2113 		}
2114 		if (blen == -1)
2115 			blen = in6_matchlen(&best_ia->ia_addr.sin6_addr, dst);
2116 		tlen = in6_matchlen(IFA_IN6(ifa), dst);
2117 		if (tlen > blen) {
2118 			blen = tlen;
2119 			best_ia = ia;
2120 		} else if (tlen == blen)
2121 			best_ia = bestia(best_ia, ia);
2122 	}
2123 	if (best_ia != NULL)
2124 		return best_ia;
2125 
2126 	IFADDR_FOREACH(ifa, ifp) {
2127 		if (ifa->ifa_addr->sa_family != AF_INET6)
2128 			continue;
2129 		ia = (struct in6_ifaddr *)ifa;
2130 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2131 			continue; /* XXX: is there any case to allow anycast? */
2132 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2133 			continue; /* don't use this interface */
2134 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2135 			continue;
2136 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2137 			if (ip6_use_deprecated)
2138 				dep[1] = (struct in6_ifaddr *)ifa;
2139 			continue;
2140 		}
2141 
2142 		best_ia = bestia(best_ia, ia);
2143 	}
2144 	if (best_ia != NULL)
2145 		return best_ia;
2146 
2147 	/* use the last-resort values, that are, deprecated addresses */
2148 	if (dep[0])
2149 		return dep[0];
2150 	if (dep[1])
2151 		return dep[1];
2152 
2153 	return NULL;
2154 }
2155 
2156 /*
2157  * perform DAD when interface becomes IFF_UP.
2158  */
2159 void
2160 in6_if_link_up(struct ifnet *ifp)
2161 {
2162 	struct ifaddr *ifa;
2163 	struct in6_ifaddr *ia;
2164 
2165 	/* Ensure it's sane to run DAD */
2166 	if (ifp->if_link_state == LINK_STATE_DOWN)
2167 		return;
2168 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
2169 		return;
2170 
2171 	IFADDR_FOREACH(ifa, ifp) {
2172 		if (ifa->ifa_addr->sa_family != AF_INET6)
2173 			continue;
2174 		ia = (struct in6_ifaddr *)ifa;
2175 
2176 		/* If detached then mark as tentative */
2177 		if (ia->ia6_flags & IN6_IFF_DETACHED) {
2178 			ia->ia6_flags &= ~IN6_IFF_DETACHED;
2179 			if (in6if_do_dad(ifp)) {
2180 				ia->ia6_flags |= IN6_IFF_TENTATIVE;
2181 				nd6log((LOG_ERR, "in6_if_up: "
2182 				    "%s marked tentative\n",
2183 				    ip6_sprintf(&ia->ia_addr.sin6_addr)));
2184 			} else if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0)
2185 				nd6_newaddrmsg(ifa);
2186 		}
2187 
2188 		if (ia->ia6_flags & IN6_IFF_TENTATIVE) {
2189 			/*
2190 			 * The TENTATIVE flag was likely set by hand
2191 			 * beforehand, implicitly indicating the need for DAD.
2192 			 * We may be able to skip the random delay in this
2193 			 * case, but we impose delays just in case.
2194 			 */
2195 			nd6_dad_start(ifa,
2196 			    cprng_fast32() %
2197 				(MAX_RTR_SOLICITATION_DELAY * hz));
2198 		}
2199 	}
2200 
2201 	/* Restore any detached prefixes */
2202 	pfxlist_onlink_check();
2203 }
2204 
2205 void
2206 in6_if_up(struct ifnet *ifp)
2207 {
2208 
2209 	/*
2210 	 * special cases, like 6to4, are handled in in6_ifattach
2211 	 */
2212 	in6_ifattach(ifp, NULL);
2213 
2214 	/* interface may not support link state, so bring it up also */
2215 	in6_if_link_up(ifp);
2216 }
2217 /*
2218  * Mark all addresses as detached.
2219  */
2220 void
2221 in6_if_link_down(struct ifnet *ifp)
2222 {
2223 	struct ifaddr *ifa;
2224 	struct in6_ifaddr *ia;
2225 
2226 	/* Any prefixes on this interface should be detached as well */
2227 	pfxlist_onlink_check();
2228 
2229 	IFADDR_FOREACH(ifa, ifp) {
2230 		if (ifa->ifa_addr->sa_family != AF_INET6)
2231 			continue;
2232 		ia = (struct in6_ifaddr *)ifa;
2233 
2234 		/* Stop DAD processing */
2235 		nd6_dad_stop(ifa);
2236 
2237 		/*
2238 		 * Mark the address as detached.
2239 		 * This satisfies RFC4862 Section 5.3, but we should apply
2240 		 * this logic to all addresses to be a good citizen and
2241 		 * avoid potential duplicated addresses.
2242 		 * When the interface comes up again, detached addresses
2243 		 * are marked tentative and DAD commences.
2244 		 */
2245 		if (!(ia->ia6_flags & IN6_IFF_DETACHED)) {
2246 			nd6log((LOG_DEBUG, "in6_if_down: "
2247 			    "%s marked detached\n",
2248 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
2249 			ia->ia6_flags |= IN6_IFF_DETACHED;
2250 			ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
2251 			nd6_newaddrmsg(ifa);
2252 		}
2253 	}
2254 }
2255 
2256 void
2257 in6_if_down(struct ifnet *ifp)
2258 {
2259 
2260 	in6_if_link_down(ifp);
2261 }
2262 
2263 int
2264 in6if_do_dad(struct ifnet *ifp)
2265 {
2266 	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2267 		return 0;
2268 
2269 	switch (ifp->if_type) {
2270 	case IFT_FAITH:
2271 		/*
2272 		 * These interfaces do not have the IFF_LOOPBACK flag,
2273 		 * but loop packets back.  We do not have to do DAD on such
2274 		 * interfaces.  We should even omit it, because loop-backed
2275 		 * NS would confuse the DAD procedure.
2276 		 */
2277 		return 0;
2278 	default:
2279 		/*
2280 		 * Our DAD routine requires the interface up and running.
2281 		 * However, some interfaces can be up before the RUNNING
2282 		 * status.  Additionaly, users may try to assign addresses
2283 		 * before the interface becomes up (or running).
2284 		 * We simply skip DAD in such a case as a work around.
2285 		 * XXX: we should rather mark "tentative" on such addresses,
2286 		 * and do DAD after the interface becomes ready.
2287 		 */
2288 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
2289 		    (IFF_UP|IFF_RUNNING))
2290 			return 0;
2291 
2292 		return 1;
2293 	}
2294 }
2295 
2296 /*
2297  * Calculate max IPv6 MTU through all the interfaces and store it
2298  * to in6_maxmtu.
2299  */
2300 void
2301 in6_setmaxmtu(void)
2302 {
2303 	unsigned long maxmtu = 0;
2304 	struct ifnet *ifp;
2305 
2306 	TAILQ_FOREACH(ifp, &ifnet, if_list) {
2307 		/* this function can be called during ifnet initialization */
2308 		if (!ifp->if_afdata[AF_INET6])
2309 			continue;
2310 		if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
2311 		    IN6_LINKMTU(ifp) > maxmtu)
2312 			maxmtu = IN6_LINKMTU(ifp);
2313 	}
2314 	if (maxmtu)	     /* update only when maxmtu is positive */
2315 		in6_maxmtu = maxmtu;
2316 }
2317 
2318 /*
2319  * Provide the length of interface identifiers to be used for the link attached
2320  * to the given interface.  The length should be defined in "IPv6 over
2321  * xxx-link" document.  Note that address architecture might also define
2322  * the length for a particular set of address prefixes, regardless of the
2323  * link type.  As clarified in rfc2462bis, those two definitions should be
2324  * consistent, and those really are as of August 2004.
2325  */
2326 int
2327 in6_if2idlen(struct ifnet *ifp)
2328 {
2329 	switch (ifp->if_type) {
2330 	case IFT_ETHER:		/* RFC2464 */
2331 	case IFT_PROPVIRTUAL:	/* XXX: no RFC. treat it as ether */
2332 	case IFT_L2VLAN:	/* ditto */
2333 	case IFT_IEEE80211:	/* ditto */
2334 	case IFT_FDDI:		/* RFC2467 */
2335 	case IFT_ISO88025:	/* RFC2470 (IPv6 over Token Ring) */
2336 	case IFT_PPP:		/* RFC2472 */
2337 	case IFT_ARCNET:	/* RFC2497 */
2338 	case IFT_FRELAY:	/* RFC2590 */
2339 	case IFT_IEEE1394:	/* RFC3146 */
2340 	case IFT_GIF:		/* draft-ietf-v6ops-mech-v2-07 */
2341 	case IFT_LOOP:		/* XXX: is this really correct? */
2342 		return 64;
2343 	default:
2344 		/*
2345 		 * Unknown link type:
2346 		 * It might be controversial to use the today's common constant
2347 		 * of 64 for these cases unconditionally.  For full compliance,
2348 		 * we should return an error in this case.  On the other hand,
2349 		 * if we simply miss the standard for the link type or a new
2350 		 * standard is defined for a new link type, the IFID length
2351 		 * is very likely to be the common constant.  As a compromise,
2352 		 * we always use the constant, but make an explicit notice
2353 		 * indicating the "unknown" case.
2354 		 */
2355 		printf("in6_if2idlen: unknown link type (%d)\n", ifp->if_type);
2356 		return 64;
2357 	}
2358 }
2359 
2360 void *
2361 in6_domifattach(struct ifnet *ifp)
2362 {
2363 	struct in6_ifextra *ext;
2364 
2365 	ext = malloc(sizeof(*ext), M_IFADDR, M_WAITOK|M_ZERO);
2366 
2367 	ext->in6_ifstat = malloc(sizeof(struct in6_ifstat),
2368 	    M_IFADDR, M_WAITOK|M_ZERO);
2369 
2370 	ext->icmp6_ifstat = malloc(sizeof(struct icmp6_ifstat),
2371 	    M_IFADDR, M_WAITOK|M_ZERO);
2372 
2373 	ext->nd_ifinfo = nd6_ifattach(ifp);
2374 	ext->scope6_id = scope6_ifattach(ifp);
2375 	ext->nprefixes = 0;
2376 	ext->ndefrouters = 0;
2377 	return ext;
2378 }
2379 
2380 void
2381 in6_domifdetach(struct ifnet *ifp, void *aux)
2382 {
2383 	struct in6_ifextra *ext = (struct in6_ifextra *)aux;
2384 
2385 	nd6_ifdetach(ext->nd_ifinfo);
2386 	free(ext->in6_ifstat, M_IFADDR);
2387 	free(ext->icmp6_ifstat, M_IFADDR);
2388 	scope6_ifdetach(ext->scope6_id);
2389 	free(ext, M_IFADDR);
2390 }
2391 
2392 /*
2393  * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
2394  * v4 mapped addr or v4 compat addr
2395  */
2396 void
2397 in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2398 {
2399 	memset(sin, 0, sizeof(*sin));
2400 	sin->sin_len = sizeof(struct sockaddr_in);
2401 	sin->sin_family = AF_INET;
2402 	sin->sin_port = sin6->sin6_port;
2403 	sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];
2404 }
2405 
2406 /* Convert sockaddr_in to sockaddr_in6 in v4 mapped addr format. */
2407 void
2408 in6_sin_2_v4mapsin6(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2409 {
2410 	memset(sin6, 0, sizeof(*sin6));
2411 	sin6->sin6_len = sizeof(struct sockaddr_in6);
2412 	sin6->sin6_family = AF_INET6;
2413 	sin6->sin6_port = sin->sin_port;
2414 	sin6->sin6_addr.s6_addr32[0] = 0;
2415 	sin6->sin6_addr.s6_addr32[1] = 0;
2416 	sin6->sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
2417 	sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;
2418 }
2419 
2420 /* Convert sockaddr_in6 into sockaddr_in. */
2421 void
2422 in6_sin6_2_sin_in_sock(struct sockaddr *nam)
2423 {
2424 	struct sockaddr_in *sin_p;
2425 	struct sockaddr_in6 sin6;
2426 
2427 	/*
2428 	 * Save original sockaddr_in6 addr and convert it
2429 	 * to sockaddr_in.
2430 	 */
2431 	sin6 = *(struct sockaddr_in6 *)nam;
2432 	sin_p = (struct sockaddr_in *)nam;
2433 	in6_sin6_2_sin(sin_p, &sin6);
2434 }
2435 
2436 /* Convert sockaddr_in into sockaddr_in6 in v4 mapped addr format. */
2437 void
2438 in6_sin_2_v4mapsin6_in_sock(struct sockaddr **nam)
2439 {
2440 	struct sockaddr_in *sin_p;
2441 	struct sockaddr_in6 *sin6_p;
2442 
2443 	sin6_p = malloc(sizeof(*sin6_p), M_SONAME, M_WAITOK);
2444 	sin_p = (struct sockaddr_in *)*nam;
2445 	in6_sin_2_v4mapsin6(sin_p, sin6_p);
2446 	free(*nam, M_SONAME);
2447 	*nam = (struct sockaddr *)sin6_p;
2448 }
2449