xref: /netbsd-src/sys/netinet6/in6.c (revision 2c6fc41c810f5088457889d00eba558e8bc74d9e)
1 /*	$NetBSD: in6.c,v 1.170 2014/05/17 20:44:24 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 1.170 2014/05/17 20:44:24 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 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     lwp_t *l)
365 {
366 	struct	in6_ifreq *ifr = (struct in6_ifreq *)data;
367 	struct	in6_ifaddr *ia = NULL;
368 	struct	in6_aliasreq *ifra = (struct in6_aliasreq *)data;
369 	struct sockaddr_in6 *sa6;
370 	int error;
371 
372 	switch (cmd) {
373 	/*
374 	 * XXX: Fix me, once we fix SIOCSIFADDR, SIOCIFDSTADDR, etc.
375 	 */
376 	case SIOCSIFADDR:
377 	case SIOCSIFDSTADDR:
378 	case SIOCSIFBRDADDR:
379 	case SIOCSIFNETMASK:
380 		return EOPNOTSUPP;
381 	case SIOCGETSGCNT_IN6:
382 	case SIOCGETMIFCNT_IN6:
383 		return mrt6_ioctl(cmd, data);
384 	case SIOCGIFADDRPREF:
385 	case SIOCSIFADDRPREF:
386 		if (ifp == NULL)
387 			return EINVAL;
388 		return ifaddrpref_ioctl(so, cmd, data, ifp, l);
389 	}
390 
391 	if (ifp == NULL)
392 		return EOPNOTSUPP;
393 
394 	switch (cmd) {
395 	case SIOCSNDFLUSH_IN6:
396 	case SIOCSPFXFLUSH_IN6:
397 	case SIOCSRTRFLUSH_IN6:
398 	case SIOCSDEFIFACE_IN6:
399 	case SIOCSIFINFO_FLAGS:
400 	case SIOCSIFINFO_IN6:
401 		/* Privileged. */
402 		/* FALLTHROUGH */
403 	case OSIOCGIFINFO_IN6:
404 	case SIOCGIFINFO_IN6:
405 	case SIOCGDRLST_IN6:
406 	case SIOCGPRLST_IN6:
407 	case SIOCGNBRINFO_IN6:
408 	case SIOCGDEFIFACE_IN6:
409 		return nd6_ioctl(cmd, data, ifp);
410 	}
411 
412 	switch (cmd) {
413 	case SIOCSIFPREFIX_IN6:
414 	case SIOCDIFPREFIX_IN6:
415 	case SIOCAIFPREFIX_IN6:
416 	case SIOCCIFPREFIX_IN6:
417 	case SIOCSGIFPREFIX_IN6:
418 	case SIOCGIFPREFIX_IN6:
419 		log(LOG_NOTICE,
420 		    "prefix ioctls are now invalidated. "
421 		    "please use ifconfig.\n");
422 		return EOPNOTSUPP;
423 	}
424 
425 	switch (cmd) {
426 	case SIOCALIFADDR:
427 	case SIOCDLIFADDR:
428 		/* Privileged. */
429 		/* FALLTHROUGH */
430 	case SIOCGLIFADDR:
431 		return in6_lifaddr_ioctl(so, cmd, data, ifp, l);
432 	}
433 
434 	/*
435 	 * Find address for this interface, if it exists.
436 	 *
437 	 * In netinet code, we have checked ifra_addr in SIOCSIF*ADDR operation
438 	 * only, and used the first interface address as the target of other
439 	 * operations (without checking ifra_addr).  This was because netinet
440 	 * code/API assumed at most 1 interface address per interface.
441 	 * Since IPv6 allows a node to assign multiple addresses
442 	 * on a single interface, we almost always look and check the
443 	 * presence of ifra_addr, and reject invalid ones here.
444 	 * It also decreases duplicated code among SIOC*_IN6 operations.
445 	 */
446 	switch (cmd) {
447 	case SIOCAIFADDR_IN6:
448 #ifdef OSIOCAIFADDR_IN6
449 	case OSIOCAIFADDR_IN6:
450 #endif
451 #ifdef OSIOCSIFPHYADDR_IN6
452 	case OSIOCSIFPHYADDR_IN6:
453 #endif
454 	case SIOCSIFPHYADDR_IN6:
455 		sa6 = &ifra->ifra_addr;
456 		break;
457 	case SIOCSIFADDR_IN6:
458 	case SIOCGIFADDR_IN6:
459 	case SIOCSIFDSTADDR_IN6:
460 	case SIOCSIFNETMASK_IN6:
461 	case SIOCGIFDSTADDR_IN6:
462 	case SIOCGIFNETMASK_IN6:
463 	case SIOCDIFADDR_IN6:
464 	case SIOCGIFPSRCADDR_IN6:
465 	case SIOCGIFPDSTADDR_IN6:
466 	case SIOCGIFAFLAG_IN6:
467 	case SIOCSNDFLUSH_IN6:
468 	case SIOCSPFXFLUSH_IN6:
469 	case SIOCSRTRFLUSH_IN6:
470 	case SIOCGIFALIFETIME_IN6:
471 #ifdef OSIOCGIFALIFETIME_IN6
472 	case OSIOCGIFALIFETIME_IN6:
473 #endif
474 	case SIOCGIFSTAT_IN6:
475 	case SIOCGIFSTAT_ICMP6:
476 		sa6 = &ifr->ifr_addr;
477 		break;
478 	default:
479 		sa6 = NULL;
480 		break;
481 	}
482 	if (sa6 && sa6->sin6_family == AF_INET6) {
483 		if (sa6->sin6_scope_id != 0)
484 			error = sa6_embedscope(sa6, 0);
485 		else
486 			error = in6_setscope(&sa6->sin6_addr, ifp, NULL);
487 		if (error != 0)
488 			return error;
489 		ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
490 	} else
491 		ia = NULL;
492 
493 	switch (cmd) {
494 	case SIOCSIFADDR_IN6:
495 	case SIOCSIFDSTADDR_IN6:
496 	case SIOCSIFNETMASK_IN6:
497 		/*
498 		 * Since IPv6 allows a node to assign multiple addresses
499 		 * on a single interface, SIOCSIFxxx ioctls are deprecated.
500 		 */
501 		return EINVAL;
502 
503 	case SIOCDIFADDR_IN6:
504 		/*
505 		 * for IPv4, we look for existing in_ifaddr here to allow
506 		 * "ifconfig if0 delete" to remove the first IPv4 address on
507 		 * the interface.  For IPv6, as the spec allows multiple
508 		 * interface address from the day one, we consider "remove the
509 		 * first one" semantics to be not preferable.
510 		 */
511 		if (ia == NULL)
512 			return EADDRNOTAVAIL;
513 		/* FALLTHROUGH */
514 #ifdef OSIOCAIFADDR_IN6
515 	case OSIOCAIFADDR_IN6:
516 #endif
517 	case SIOCAIFADDR_IN6:
518 		/*
519 		 * We always require users to specify a valid IPv6 address for
520 		 * the corresponding operation.
521 		 */
522 		if (ifra->ifra_addr.sin6_family != AF_INET6 ||
523 		    ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6))
524 			return EAFNOSUPPORT;
525 		/* Privileged. */
526 
527 		break;
528 
529 	case SIOCGIFADDR_IN6:
530 		/* This interface is basically deprecated. use SIOCGIFCONF. */
531 		/* FALLTHROUGH */
532 	case SIOCGIFAFLAG_IN6:
533 	case SIOCGIFNETMASK_IN6:
534 	case SIOCGIFDSTADDR_IN6:
535 	case SIOCGIFALIFETIME_IN6:
536 #ifdef OSIOCGIFALIFETIME_IN6
537 	case OSIOCGIFALIFETIME_IN6:
538 #endif
539 		/* must think again about its semantics */
540 		if (ia == NULL)
541 			return EADDRNOTAVAIL;
542 		break;
543 	}
544 
545 	switch (cmd) {
546 
547 	case SIOCGIFADDR_IN6:
548 		ifr->ifr_addr = ia->ia_addr;
549 		if ((error = sa6_recoverscope(&ifr->ifr_addr)) != 0)
550 			return error;
551 		break;
552 
553 	case SIOCGIFDSTADDR_IN6:
554 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
555 			return EINVAL;
556 		/*
557 		 * XXX: should we check if ifa_dstaddr is NULL and return
558 		 * an error?
559 		 */
560 		ifr->ifr_dstaddr = ia->ia_dstaddr;
561 		if ((error = sa6_recoverscope(&ifr->ifr_dstaddr)) != 0)
562 			return error;
563 		break;
564 
565 	case SIOCGIFNETMASK_IN6:
566 		ifr->ifr_addr = ia->ia_prefixmask;
567 		break;
568 
569 	case SIOCGIFAFLAG_IN6:
570 		ifr->ifr_ifru.ifru_flags6 = ia->ia6_flags;
571 		break;
572 
573 	case SIOCGIFSTAT_IN6:
574 		if (ifp == NULL)
575 			return EINVAL;
576 		memset(&ifr->ifr_ifru.ifru_stat, 0,
577 		    sizeof(ifr->ifr_ifru.ifru_stat));
578 		ifr->ifr_ifru.ifru_stat =
579 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->in6_ifstat;
580 		break;
581 
582 	case SIOCGIFSTAT_ICMP6:
583 		if (ifp == NULL)
584 			return EINVAL;
585 		memset(&ifr->ifr_ifru.ifru_icmp6stat, 0,
586 		    sizeof(ifr->ifr_ifru.ifru_icmp6stat));
587 		ifr->ifr_ifru.ifru_icmp6stat =
588 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->icmp6_ifstat;
589 		break;
590 
591 #ifdef OSIOCGIFALIFETIME_IN6
592 	case OSIOCGIFALIFETIME_IN6:
593 #endif
594 	case SIOCGIFALIFETIME_IN6:
595 		ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
596 		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
597 			time_t maxexpire;
598 			struct in6_addrlifetime *retlt =
599 			    &ifr->ifr_ifru.ifru_lifetime;
600 
601 			/*
602 			 * XXX: adjust expiration time assuming time_t is
603 			 * signed.
604 			 */
605 			maxexpire = ((time_t)~0) &
606 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
607 			if (ia->ia6_lifetime.ia6t_vltime <
608 			    maxexpire - ia->ia6_updatetime) {
609 				retlt->ia6t_expire = ia->ia6_updatetime +
610 				    ia->ia6_lifetime.ia6t_vltime;
611 			} else
612 				retlt->ia6t_expire = maxexpire;
613 		}
614 		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
615 			time_t maxexpire;
616 			struct in6_addrlifetime *retlt =
617 			    &ifr->ifr_ifru.ifru_lifetime;
618 
619 			/*
620 			 * XXX: adjust expiration time assuming time_t is
621 			 * signed.
622 			 */
623 			maxexpire = ((time_t)~0) &
624 			    ~((time_t)1 << ((sizeof(maxexpire) * NBBY) - 1));
625 			if (ia->ia6_lifetime.ia6t_pltime <
626 			    maxexpire - ia->ia6_updatetime) {
627 				retlt->ia6t_preferred = ia->ia6_updatetime +
628 				    ia->ia6_lifetime.ia6t_pltime;
629 			} else
630 				retlt->ia6t_preferred = maxexpire;
631 		}
632 #ifdef OSIOCFIFALIFETIME_IN6
633 		if (cmd == OSIOCFIFALIFETIME_IN6)
634 			in6_addrlifetime_to_in6_addrlifetime50(
635 			    &ifr->ifru.ifru_lifetime);
636 #endif
637 		break;
638 
639 #ifdef OSIOCAIFADDR_IN6
640 	case OSIOCAIFADDR_IN6:
641 		in6_aliasreq50_to_in6_aliasreq(ifra);
642 		/*FALLTHROUGH*/
643 #endif
644 	case SIOCAIFADDR_IN6:
645 	{
646 		int i;
647 		struct nd_prefixctl pr0;
648 		struct nd_prefix *pr;
649 
650 		/* reject read-only flags */
651 		if ((ifra->ifra_flags & IN6_IFF_DUPLICATED) != 0 ||
652 		    (ifra->ifra_flags & IN6_IFF_DETACHED) != 0 ||
653 		    (ifra->ifra_flags & IN6_IFF_NODAD) != 0 ||
654 		    (ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0) {
655 			return EINVAL;
656 		}
657 		/*
658 		 * first, make or update the interface address structure,
659 		 * and link it to the list.
660 		 */
661 		if ((error = in6_update_ifa(ifp, ifra, ia, 0)) != 0)
662 			return error;
663 		if ((ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr))
664 		    == NULL) {
665 		    	/*
666 			 * this can happen when the user specify the 0 valid
667 			 * lifetime.
668 			 */
669 			break;
670 		}
671 
672 		/*
673 		 * then, make the prefix on-link on the interface.
674 		 * XXX: we'd rather create the prefix before the address, but
675 		 * we need at least one address to install the corresponding
676 		 * interface route, so we configure the address first.
677 		 */
678 
679 		/*
680 		 * convert mask to prefix length (prefixmask has already
681 		 * been validated in in6_update_ifa().
682 		 */
683 		memset(&pr0, 0, sizeof(pr0));
684 		pr0.ndpr_ifp = ifp;
685 		pr0.ndpr_plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
686 		    NULL);
687 		if (pr0.ndpr_plen == 128) {
688 			break;	/* we don't need to install a host route. */
689 		}
690 		pr0.ndpr_prefix = ifra->ifra_addr;
691 		/* apply the mask for safety. */
692 		for (i = 0; i < 4; i++) {
693 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
694 			    ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
695 		}
696 		/*
697 		 * XXX: since we don't have an API to set prefix (not address)
698 		 * lifetimes, we just use the same lifetimes as addresses.
699 		 * The (temporarily) installed lifetimes can be overridden by
700 		 * later advertised RAs (when accept_rtadv is non 0), which is
701 		 * an intended behavior.
702 		 */
703 		pr0.ndpr_raf_onlink = 1; /* should be configurable? */
704 		pr0.ndpr_raf_auto =
705 		    ((ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0);
706 		pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
707 		pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;
708 
709 		/* add the prefix if not yet. */
710 		if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
711 			/*
712 			 * nd6_prelist_add will install the corresponding
713 			 * interface route.
714 			 */
715 			if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
716 				return error;
717 			if (pr == NULL) {
718 				log(LOG_ERR, "nd6_prelist_add succeeded but "
719 				    "no prefix\n");
720 				return EINVAL; /* XXX panic here? */
721 			}
722 		}
723 
724 		/* relate the address to the prefix */
725 		if (ia->ia6_ndpr == NULL) {
726 			ia->ia6_ndpr = pr;
727 			pr->ndpr_refcnt++;
728 
729 			/*
730 			 * If this is the first autoconf address from the
731 			 * prefix, create a temporary address as well
732 			 * (when required).
733 			 */
734 			if ((ia->ia6_flags & IN6_IFF_AUTOCONF) &&
735 			    ip6_use_tempaddr && pr->ndpr_refcnt == 1) {
736 				int e;
737 				if ((e = in6_tmpifadd(ia, 1, 0)) != 0) {
738 					log(LOG_NOTICE, "in6_control: failed "
739 					    "to create a temporary address, "
740 					    "errno=%d\n", e);
741 				}
742 			}
743 		}
744 
745 		/*
746 		 * this might affect the status of autoconfigured addresses,
747 		 * that is, this address might make other addresses detached.
748 		 */
749 		pfxlist_onlink_check();
750 
751 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCAIFADDR_IN6,
752 		    ifp, PFIL_IFADDR);
753 		break;
754 	}
755 
756 	case SIOCDIFADDR_IN6:
757 	{
758 		struct nd_prefix *pr;
759 
760 		/*
761 		 * If the address being deleted is the only one that owns
762 		 * the corresponding prefix, expire the prefix as well.
763 		 * XXX: theoretically, we don't have to worry about such
764 		 * relationship, since we separate the address management
765 		 * and the prefix management.  We do this, however, to provide
766 		 * as much backward compatibility as possible in terms of
767 		 * the ioctl operation.
768 		 * Note that in6_purgeaddr() will decrement ndpr_refcnt.
769 		 */
770 		pr = ia->ia6_ndpr;
771 		in6_purgeaddr(&ia->ia_ifa);
772 		if (pr && pr->ndpr_refcnt == 0)
773 			prelist_remove(pr);
774 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCDIFADDR_IN6,
775 		    ifp, PFIL_IFADDR);
776 		break;
777 	}
778 
779 	default:
780 		return ENOTTY;
781 	}
782 
783 	return 0;
784 }
785 
786 int
787 in6_control(struct socket *so, u_long cmd, void *data, struct ifnet *ifp,
788     struct lwp *l)
789 {
790 	int error, s;
791 
792 	switch (cmd) {
793 	case SIOCSNDFLUSH_IN6:
794 	case SIOCSPFXFLUSH_IN6:
795 	case SIOCSRTRFLUSH_IN6:
796 	case SIOCSDEFIFACE_IN6:
797 	case SIOCSIFINFO_FLAGS:
798 	case SIOCSIFINFO_IN6:
799 
800 	case SIOCALIFADDR:
801 	case SIOCDLIFADDR:
802 
803 	case SIOCDIFADDR_IN6:
804 #ifdef OSIOCAIFADDR_IN6
805 	case OSIOCAIFADDR_IN6:
806 #endif
807 	case SIOCAIFADDR_IN6:
808 		if (kauth_authorize_network(l->l_cred,
809 		    KAUTH_NETWORK_SOCKET,
810 		    KAUTH_REQ_NETWORK_SOCKET_SETPRIV,
811 		    so, NULL, NULL))
812 			return EPERM;
813 		break;
814 	}
815 
816 	s = splnet();
817 	error = in6_control1(so , cmd, data, ifp, l);
818 	splx(s);
819 	return error;
820 }
821 
822 /*
823  * Update parameters of an IPv6 interface address.
824  * If necessary, a new entry is created and linked into address chains.
825  * This function is separated from in6_control().
826  * XXX: should this be performed under splnet()?
827  */
828 static int
829 in6_update_ifa1(struct ifnet *ifp, struct in6_aliasreq *ifra,
830     struct in6_ifaddr *ia, int flags)
831 {
832 	int error = 0, hostIsNew = 0, plen = -1;
833 	struct in6_ifaddr *oia;
834 	struct sockaddr_in6 dst6;
835 	struct in6_addrlifetime *lt;
836 	struct in6_multi_mship *imm;
837 	struct in6_multi *in6m_sol;
838 	struct rtentry *rt;
839 	int dad_delay;
840 
841 	in6m_sol = NULL;
842 
843 	/* Validate parameters */
844 	if (ifp == NULL || ifra == NULL) /* this maybe redundant */
845 		return EINVAL;
846 
847 	/*
848 	 * The destination address for a p2p link must have a family
849 	 * of AF_UNSPEC or AF_INET6.
850 	 */
851 	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
852 	    ifra->ifra_dstaddr.sin6_family != AF_INET6 &&
853 	    ifra->ifra_dstaddr.sin6_family != AF_UNSPEC)
854 		return EAFNOSUPPORT;
855 	/*
856 	 * validate ifra_prefixmask.  don't check sin6_family, netmask
857 	 * does not carry fields other than sin6_len.
858 	 */
859 	if (ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6))
860 		return EINVAL;
861 	/*
862 	 * Because the IPv6 address architecture is classless, we require
863 	 * users to specify a (non 0) prefix length (mask) for a new address.
864 	 * We also require the prefix (when specified) mask is valid, and thus
865 	 * reject a non-consecutive mask.
866 	 */
867 	if (ia == NULL && ifra->ifra_prefixmask.sin6_len == 0)
868 		return EINVAL;
869 	if (ifra->ifra_prefixmask.sin6_len != 0) {
870 		plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
871 		    (u_char *)&ifra->ifra_prefixmask +
872 		    ifra->ifra_prefixmask.sin6_len);
873 		if (plen <= 0)
874 			return EINVAL;
875 	} else {
876 		/*
877 		 * In this case, ia must not be NULL.  We just use its prefix
878 		 * length.
879 		 */
880 		plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
881 	}
882 	/*
883 	 * If the destination address on a p2p interface is specified,
884 	 * and the address is a scoped one, validate/set the scope
885 	 * zone identifier.
886 	 */
887 	dst6 = ifra->ifra_dstaddr;
888 	if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) != 0 &&
889 	    (dst6.sin6_family == AF_INET6)) {
890 		struct in6_addr in6_tmp;
891 		u_int32_t zoneid;
892 
893 		in6_tmp = dst6.sin6_addr;
894 		if (in6_setscope(&in6_tmp, ifp, &zoneid))
895 			return EINVAL; /* XXX: should be impossible */
896 
897 		if (dst6.sin6_scope_id != 0) {
898 			if (dst6.sin6_scope_id != zoneid)
899 				return EINVAL;
900 		} else		/* user omit to specify the ID. */
901 			dst6.sin6_scope_id = zoneid;
902 
903 		/* convert into the internal form */
904 		if (sa6_embedscope(&dst6, 0))
905 			return EINVAL; /* XXX: should be impossible */
906 	}
907 	/*
908 	 * The destination address can be specified only for a p2p or a
909 	 * loopback interface.  If specified, the corresponding prefix length
910 	 * must be 128.
911 	 */
912 	if (ifra->ifra_dstaddr.sin6_family == AF_INET6) {
913 #ifdef FORCE_P2PPLEN
914 		int i;
915 #endif
916 
917 		if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) == 0) {
918 			/* XXX: noisy message */
919 			nd6log((LOG_INFO, "in6_update_ifa: a destination can "
920 			    "be specified for a p2p or a loopback IF only\n"));
921 			return EINVAL;
922 		}
923 		if (plen != 128) {
924 			nd6log((LOG_INFO, "in6_update_ifa: prefixlen should "
925 			    "be 128 when dstaddr is specified\n"));
926 #ifdef FORCE_P2PPLEN
927 			/*
928 			 * To be compatible with old configurations,
929 			 * such as ifconfig gif0 inet6 2001::1 2001::2
930 			 * prefixlen 126, we override the specified
931 			 * prefixmask as if the prefix length was 128.
932 			 */
933 			ifra->ifra_prefixmask.sin6_len =
934 			    sizeof(struct sockaddr_in6);
935 			for (i = 0; i < 4; i++)
936 				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i] =
937 				    0xffffffff;
938 			plen = 128;
939 #else
940 			return EINVAL;
941 #endif
942 		}
943 	}
944 	/* lifetime consistency check */
945 	lt = &ifra->ifra_lifetime;
946 	if (lt->ia6t_pltime > lt->ia6t_vltime)
947 		return EINVAL;
948 	if (lt->ia6t_vltime == 0) {
949 		/*
950 		 * the following log might be noisy, but this is a typical
951 		 * configuration mistake or a tool's bug.
952 		 */
953 		nd6log((LOG_INFO,
954 		    "in6_update_ifa: valid lifetime is 0 for %s\n",
955 		    ip6_sprintf(&ifra->ifra_addr.sin6_addr)));
956 
957 		if (ia == NULL)
958 			return 0; /* there's nothing to do */
959 	}
960 
961 	/*
962 	 * If this is a new address, allocate a new ifaddr and link it
963 	 * into chains.
964 	 */
965 	if (ia == NULL) {
966 		hostIsNew = 1;
967 		/*
968 		 * When in6_update_ifa() is called in a process of a received
969 		 * RA, it is called under an interrupt context.  So, we should
970 		 * call malloc with M_NOWAIT.
971 		 */
972 		ia = (struct in6_ifaddr *) malloc(sizeof(*ia), M_IFADDR,
973 		    M_NOWAIT);
974 		if (ia == NULL)
975 			return ENOBUFS;
976 		memset(ia, 0, sizeof(*ia));
977 		LIST_INIT(&ia->ia6_memberships);
978 		/* Initialize the address and masks, and put time stamp */
979 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
980 		ia->ia_addr.sin6_family = AF_INET6;
981 		ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
982 		ia->ia6_createtime = time_second;
983 		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
984 			/*
985 			 * XXX: some functions expect that ifa_dstaddr is not
986 			 * NULL for p2p interfaces.
987 			 */
988 			ia->ia_ifa.ifa_dstaddr =
989 			    (struct sockaddr *)&ia->ia_dstaddr;
990 		} else {
991 			ia->ia_ifa.ifa_dstaddr = NULL;
992 		}
993 		ia->ia_ifa.ifa_netmask =
994 		    (struct sockaddr *)&ia->ia_prefixmask;
995 
996 		ia->ia_ifp = ifp;
997 		if ((oia = in6_ifaddr) != NULL) {
998 			for ( ; oia->ia_next; oia = oia->ia_next)
999 				continue;
1000 			oia->ia_next = ia;
1001 		} else
1002 			in6_ifaddr = ia;
1003 		/* gain a refcnt for the link from in6_ifaddr */
1004 		IFAREF(&ia->ia_ifa);
1005 
1006 		ifa_insert(ifp, &ia->ia_ifa);
1007 	}
1008 
1009 	/* update timestamp */
1010 	ia->ia6_updatetime = time_second;
1011 
1012 	/* set prefix mask */
1013 	if (ifra->ifra_prefixmask.sin6_len) {
1014 		/*
1015 		 * We prohibit changing the prefix length of an existing
1016 		 * address, because
1017 		 * + such an operation should be rare in IPv6, and
1018 		 * + the operation would confuse prefix management.
1019 		 */
1020 		if (ia->ia_prefixmask.sin6_len &&
1021 		    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL) != plen) {
1022 			nd6log((LOG_INFO, "in6_update_ifa: the prefix length of an"
1023 			    " existing (%s) address should not be changed\n",
1024 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1025 			error = EINVAL;
1026 			goto unlink;
1027 		}
1028 		ia->ia_prefixmask = ifra->ifra_prefixmask;
1029 	}
1030 
1031 	/*
1032 	 * If a new destination address is specified, scrub the old one and
1033 	 * install the new destination.  Note that the interface must be
1034 	 * p2p or loopback (see the check above.)
1035 	 */
1036 	if (dst6.sin6_family == AF_INET6 &&
1037 	    !IN6_ARE_ADDR_EQUAL(&dst6.sin6_addr, &ia->ia_dstaddr.sin6_addr)) {
1038 		if ((ia->ia_flags & IFA_ROUTE) != 0 &&
1039 		    rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST) != 0) {
1040 			nd6log((LOG_ERR, "in6_update_ifa: failed to remove "
1041 			    "a route to the old destination: %s\n",
1042 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
1043 			/* proceed anyway... */
1044 		} else
1045 			ia->ia_flags &= ~IFA_ROUTE;
1046 		ia->ia_dstaddr = dst6;
1047 	}
1048 
1049 	/*
1050 	 * Set lifetimes.  We do not refer to ia6t_expire and ia6t_preferred
1051 	 * to see if the address is deprecated or invalidated, but initialize
1052 	 * these members for applications.
1053 	 */
1054 	ia->ia6_lifetime = ifra->ifra_lifetime;
1055 	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
1056 		ia->ia6_lifetime.ia6t_expire =
1057 		    time_second + ia->ia6_lifetime.ia6t_vltime;
1058 	} else
1059 		ia->ia6_lifetime.ia6t_expire = 0;
1060 	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
1061 		ia->ia6_lifetime.ia6t_preferred =
1062 		    time_second + ia->ia6_lifetime.ia6t_pltime;
1063 	} else
1064 		ia->ia6_lifetime.ia6t_preferred = 0;
1065 
1066 	/*
1067 	 * configure address flags.
1068 	 */
1069 	ia->ia6_flags = ifra->ifra_flags;
1070 
1071 	/*
1072 	 * Make the address tentative before joining multicast addresses,
1073 	 * so that corresponding MLD responses would not have a tentative
1074 	 * source address.
1075 	 */
1076 	ia->ia6_flags &= ~IN6_IFF_DUPLICATED;	/* safety */
1077 	if (ifp->if_link_state == LINK_STATE_DOWN) {
1078 		ia->ia6_flags |= IN6_IFF_DETACHED;
1079 		ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1080 	} else if (hostIsNew && in6if_do_dad(ifp))
1081 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
1082 
1083 	/*
1084 	 * backward compatibility - if IN6_IFF_DEPRECATED is set from the
1085 	 * userland, make it deprecated.
1086 	 */
1087 	if ((ifra->ifra_flags & IN6_IFF_DEPRECATED) != 0) {
1088 		ia->ia6_lifetime.ia6t_pltime = 0;
1089 		ia->ia6_lifetime.ia6t_preferred = time_second;
1090 	}
1091 
1092 	/* reset the interface and routing table appropriately. */
1093 	if ((error = in6_ifinit(ifp, ia, &ifra->ifra_addr, hostIsNew)) != 0)
1094 		goto unlink;
1095 	/*
1096 	 * We are done if we have simply modified an existing address.
1097 	 */
1098 	if (!hostIsNew)
1099 		return error;
1100 
1101 	/*
1102 	 * Beyond this point, we should call in6_purgeaddr upon an error,
1103 	 * not just go to unlink.
1104 	 */
1105 
1106 	/* join necessary multicast groups */
1107 	if ((ifp->if_flags & IFF_MULTICAST) != 0) {
1108 		struct sockaddr_in6 mltaddr, mltmask;
1109 		struct in6_addr llsol;
1110 
1111 		/* join solicited multicast addr for new host id */
1112 		memset(&llsol, 0, sizeof(struct in6_addr));
1113 		llsol.s6_addr16[0] = htons(0xff02);
1114 		llsol.s6_addr32[1] = 0;
1115 		llsol.s6_addr32[2] = htonl(1);
1116 		llsol.s6_addr32[3] = ifra->ifra_addr.sin6_addr.s6_addr32[3];
1117 		llsol.s6_addr8[12] = 0xff;
1118 		if ((error = in6_setscope(&llsol, ifp, NULL)) != 0) {
1119 			/* XXX: should not happen */
1120 			log(LOG_ERR, "in6_update_ifa: "
1121 			    "in6_setscope failed\n");
1122 			goto cleanup;
1123 		}
1124 		dad_delay = 0;
1125 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1126 			/*
1127 			 * We need a random delay for DAD on the address
1128 			 * being configured.  It also means delaying
1129 			 * transmission of the corresponding MLD report to
1130 			 * avoid report collision.
1131 			 * [draft-ietf-ipv6-rfc2462bis-02.txt]
1132 			 */
1133 			dad_delay = cprng_fast32() %
1134 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1135 		}
1136 
1137 #define	MLTMASK_LEN  4	/* mltmask's masklen (=32bit=4octet) */
1138 		/* join solicited multicast addr for new host id */
1139 		imm = in6_joingroup(ifp, &llsol, &error, dad_delay);
1140 		if (!imm) {
1141 			nd6log((LOG_ERR,
1142 			    "in6_update_ifa: addmulti "
1143 			    "failed for %s on %s (errno=%d)\n",
1144 			    ip6_sprintf(&llsol), if_name(ifp), error));
1145 			goto cleanup;
1146 		}
1147 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1148 		in6m_sol = imm->i6mm_maddr;
1149 
1150 		sockaddr_in6_init(&mltmask, &in6mask32, 0, 0, 0);
1151 
1152 		/*
1153 		 * join link-local all-nodes address
1154 		 */
1155 		sockaddr_in6_init(&mltaddr, &in6addr_linklocal_allnodes,
1156 		    0, 0, 0);
1157 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1158 			goto cleanup; /* XXX: should not fail */
1159 
1160 		/*
1161 		 * XXX: do we really need this automatic routes?
1162 		 * We should probably reconsider this stuff.  Most applications
1163 		 * actually do not need the routes, since they usually specify
1164 		 * the outgoing interface.
1165 		 */
1166 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1167 		if (rt) {
1168 			if (memcmp(&mltaddr.sin6_addr,
1169 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1170 			    MLTMASK_LEN)) {
1171 				RTFREE(rt);
1172 				rt = NULL;
1173 			} else if (rt->rt_ifp != ifp) {
1174 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1175 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1176 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1177 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1178 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1179 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1180 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1181 				rt_replace_ifa(rt, &ia->ia_ifa);
1182 				rt->rt_ifp = ifp;
1183 			}
1184 		}
1185 		if (!rt) {
1186 			struct rt_addrinfo info;
1187 
1188 			memset(&info, 0, sizeof(info));
1189 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1190 			info.rti_info[RTAX_GATEWAY] =
1191 			    (struct sockaddr *)&ia->ia_addr;
1192 			info.rti_info[RTAX_NETMASK] =
1193 			    (struct sockaddr *)&mltmask;
1194 			info.rti_info[RTAX_IFA] =
1195 			    (struct sockaddr *)&ia->ia_addr;
1196 			/* XXX: we need RTF_CLONING to fake nd6_rtrequest */
1197 			info.rti_flags = RTF_UP | RTF_CLONING;
1198 			error = rtrequest1(RTM_ADD, &info, NULL);
1199 			if (error)
1200 				goto cleanup;
1201 		} else {
1202 			RTFREE(rt);
1203 		}
1204 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1205 		if (!imm) {
1206 			nd6log((LOG_WARNING,
1207 			    "in6_update_ifa: addmulti failed for "
1208 			    "%s on %s (errno=%d)\n",
1209 			    ip6_sprintf(&mltaddr.sin6_addr),
1210 			    if_name(ifp), error));
1211 			goto cleanup;
1212 		}
1213 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1214 
1215 		/*
1216 		 * join node information group address
1217 		 */
1218 		dad_delay = 0;
1219 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1220 			/*
1221 			 * The spec doesn't say anything about delay for this
1222 			 * group, but the same logic should apply.
1223 			 */
1224 			dad_delay = cprng_fast32() %
1225 			    (MAX_RTR_SOLICITATION_DELAY * hz);
1226 		}
1227 		if (in6_nigroup(ifp, hostname, hostnamelen, &mltaddr) != 0)
1228 			;
1229 		else if ((imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error,
1230 		          dad_delay)) == NULL) { /* XXX jinmei */
1231 			nd6log((LOG_WARNING, "in6_update_ifa: "
1232 			    "addmulti failed for %s on %s (errno=%d)\n",
1233 			    ip6_sprintf(&mltaddr.sin6_addr),
1234 			    if_name(ifp), error));
1235 			/* XXX not very fatal, go on... */
1236 		} else {
1237 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1238 		}
1239 
1240 
1241 		/*
1242 		 * join interface-local all-nodes address.
1243 		 * (ff01::1%ifN, and ff01::%ifN/32)
1244 		 */
1245 		mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
1246 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0)
1247 			goto cleanup; /* XXX: should not fail */
1248 
1249 		/* XXX: again, do we really need the route? */
1250 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1251 		if (rt) {
1252 			/* 32bit came from "mltmask" */
1253 			if (memcmp(&mltaddr.sin6_addr,
1254 			    &satocsin6(rt_getkey(rt))->sin6_addr,
1255 			    32 / NBBY)) {
1256 				RTFREE(rt);
1257 				rt = NULL;
1258 			} else if (rt->rt_ifp != ifp) {
1259 				IN6_DPRINTF("%s: rt_ifp %p -> %p (%s) "
1260 				    "network %04x:%04x::/32 = %04x:%04x::/32\n",
1261 				    __func__, rt->rt_ifp, ifp, ifp->if_xname,
1262 				    ntohs(mltaddr.sin6_addr.s6_addr16[0]),
1263 				    ntohs(mltaddr.sin6_addr.s6_addr16[1]),
1264 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[0],
1265 				    satocsin6(rt_getkey(rt))->sin6_addr.s6_addr16[1]);
1266 				rt_replace_ifa(rt, &ia->ia_ifa);
1267 				rt->rt_ifp = ifp;
1268 			}
1269 		}
1270 		if (!rt) {
1271 			struct rt_addrinfo info;
1272 
1273 			memset(&info, 0, sizeof(info));
1274 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1275 			info.rti_info[RTAX_GATEWAY] =
1276 			    (struct sockaddr *)&ia->ia_addr;
1277 			info.rti_info[RTAX_NETMASK] =
1278 			    (struct sockaddr *)&mltmask;
1279 			info.rti_info[RTAX_IFA] =
1280 			    (struct sockaddr *)&ia->ia_addr;
1281 			info.rti_flags = RTF_UP | RTF_CLONING;
1282 			error = rtrequest1(RTM_ADD, &info, NULL);
1283 			if (error)
1284 				goto cleanup;
1285 #undef	MLTMASK_LEN
1286 		} else {
1287 			RTFREE(rt);
1288 		}
1289 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
1290 		if (!imm) {
1291 			nd6log((LOG_WARNING, "in6_update_ifa: "
1292 			    "addmulti failed for %s on %s (errno=%d)\n",
1293 			    ip6_sprintf(&mltaddr.sin6_addr),
1294 			    if_name(ifp), error));
1295 			goto cleanup;
1296 		} else {
1297 			LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1298 		}
1299 	}
1300 
1301 	/*
1302 	 * Perform DAD, if needed.
1303 	 * XXX It may be of use, if we can administratively
1304 	 * disable DAD.
1305 	 */
1306 	if (hostIsNew && in6if_do_dad(ifp) &&
1307 	    ((ifra->ifra_flags & IN6_IFF_NODAD) == 0) &&
1308 	    (ia->ia6_flags & IN6_IFF_TENTATIVE))
1309 	{
1310 		int mindelay, maxdelay;
1311 
1312 		dad_delay = 0;
1313 		if ((flags & IN6_IFAUPDATE_DADDELAY)) {
1314 			/*
1315 			 * We need to impose a delay before sending an NS
1316 			 * for DAD.  Check if we also needed a delay for the
1317 			 * corresponding MLD message.  If we did, the delay
1318 			 * should be larger than the MLD delay (this could be
1319 			 * relaxed a bit, but this simple logic is at least
1320 			 * safe).
1321 			 */
1322 			mindelay = 0;
1323 			if (in6m_sol != NULL &&
1324 			    in6m_sol->in6m_state == MLD_REPORTPENDING) {
1325 				mindelay = in6m_sol->in6m_timer;
1326 			}
1327 			maxdelay = MAX_RTR_SOLICITATION_DELAY * hz;
1328 			if (maxdelay - mindelay == 0)
1329 				dad_delay = 0;
1330 			else {
1331 				dad_delay =
1332 				    (cprng_fast32() % (maxdelay - mindelay)) +
1333 				    mindelay;
1334 			}
1335 		}
1336 		nd6_dad_start(&ia->ia_ifa, dad_delay);
1337 	}
1338 
1339 	return error;
1340 
1341   unlink:
1342 	/*
1343 	 * XXX: if a change of an existing address failed, keep the entry
1344 	 * anyway.
1345 	 */
1346 	if (hostIsNew)
1347 		in6_unlink_ifa(ia, ifp);
1348 	return error;
1349 
1350   cleanup:
1351 	in6_purgeaddr(&ia->ia_ifa);
1352 	return error;
1353 }
1354 
1355 int
1356 in6_update_ifa(struct ifnet *ifp, struct in6_aliasreq *ifra,
1357     struct in6_ifaddr *ia, int flags)
1358 {
1359 	int rc, s;
1360 
1361 	s = splnet();
1362 	rc = in6_update_ifa1(ifp, ifra, ia, flags);
1363 	splx(s);
1364 	return rc;
1365 }
1366 
1367 void
1368 in6_purgeaddr(struct ifaddr *ifa)
1369 {
1370 	struct ifnet *ifp = ifa->ifa_ifp;
1371 	struct in6_ifaddr *ia = (struct in6_ifaddr *) ifa;
1372 	struct in6_multi_mship *imm;
1373 
1374 	/* stop DAD processing */
1375 	nd6_dad_stop(ifa);
1376 
1377 	/*
1378 	 * delete route to the destination of the address being purged.
1379 	 * The interface must be p2p or loopback in this case.
1380 	 */
1381 	if ((ia->ia_flags & IFA_ROUTE) != 0 && ia->ia_dstaddr.sin6_len != 0) {
1382 		int e;
1383 
1384 		if ((e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
1385 		    != 0) {
1386 			log(LOG_ERR, "in6_purgeaddr: failed to remove "
1387 			    "a route to the p2p destination: %s on %s, "
1388 			    "errno=%d\n",
1389 			    ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
1390 			    e);
1391 			/* proceed anyway... */
1392 		} else
1393 			ia->ia_flags &= ~IFA_ROUTE;
1394 	}
1395 
1396 	/* Remove ownaddr's loopback rtentry, if it exists. */
1397 	in6_ifremloop(&(ia->ia_ifa));
1398 
1399 	/*
1400 	 * leave from multicast groups we have joined for the interface
1401 	 */
1402 	while ((imm = LIST_FIRST(&ia->ia6_memberships)) != NULL) {
1403 		LIST_REMOVE(imm, i6mm_chain);
1404 		in6_leavegroup(imm);
1405 	}
1406 
1407 	in6_unlink_ifa(ia, ifp);
1408 }
1409 
1410 static void
1411 in6_unlink_ifa(struct in6_ifaddr *ia, struct ifnet *ifp)
1412 {
1413 	struct in6_ifaddr *oia;
1414 	int	s = splnet();
1415 
1416 	ifa_remove(ifp, &ia->ia_ifa);
1417 
1418 	oia = ia;
1419 	if (oia == (ia = in6_ifaddr))
1420 		in6_ifaddr = ia->ia_next;
1421 	else {
1422 		while (ia->ia_next && (ia->ia_next != oia))
1423 			ia = ia->ia_next;
1424 		if (ia->ia_next)
1425 			ia->ia_next = oia->ia_next;
1426 		else {
1427 			/* search failed */
1428 			printf("Couldn't unlink in6_ifaddr from in6_ifaddr\n");
1429 		}
1430 	}
1431 
1432 	/*
1433 	 * XXX thorpej@NetBSD.org -- if the interface is going
1434 	 * XXX away, don't save the multicast entries, delete them!
1435 	 */
1436 	if (LIST_EMPTY(&oia->ia6_multiaddrs))
1437 		;
1438 	else if (oia->ia_ifa.ifa_ifp->if_output == if_nulloutput) {
1439 		struct in6_multi *in6m, *next;
1440 
1441 		for (in6m = LIST_FIRST(&oia->ia6_multiaddrs); in6m != NULL;
1442 		     in6m = next) {
1443 			next = LIST_NEXT(in6m, in6m_entry);
1444 			in6_delmulti(in6m);
1445 		}
1446 	} else
1447 		in6_savemkludge(oia);
1448 
1449 	/*
1450 	 * Release the reference to the base prefix.  There should be a
1451 	 * positive reference.
1452 	 */
1453 	if (oia->ia6_ndpr == NULL) {
1454 		nd6log((LOG_NOTICE, "in6_unlink_ifa: autoconf'ed address "
1455 		    "%p has no prefix\n", oia));
1456 	} else {
1457 		oia->ia6_ndpr->ndpr_refcnt--;
1458 		oia->ia6_ndpr = NULL;
1459 	}
1460 
1461 	/*
1462 	 * Also, if the address being removed is autoconf'ed, call
1463 	 * pfxlist_onlink_check() since the release might affect the status of
1464 	 * other (detached) addresses.
1465 	 */
1466 	if ((oia->ia6_flags & IN6_IFF_AUTOCONF) != 0)
1467 		pfxlist_onlink_check();
1468 
1469 	/*
1470 	 * release another refcnt for the link from in6_ifaddr.
1471 	 * Note that we should decrement the refcnt at least once for all *BSD.
1472 	 */
1473 	IFAFREE(&oia->ia_ifa);
1474 
1475 	splx(s);
1476 }
1477 
1478 void
1479 in6_purgeif(struct ifnet *ifp)
1480 {
1481 	if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr);
1482 
1483 	in6_ifdetach(ifp);
1484 }
1485 
1486 /*
1487  * SIOC[GAD]LIFADDR.
1488  *	SIOCGLIFADDR: get first address. (?)
1489  *	SIOCGLIFADDR with IFLR_PREFIX:
1490  *		get first address that matches the specified prefix.
1491  *	SIOCALIFADDR: add the specified address.
1492  *	SIOCALIFADDR with IFLR_PREFIX:
1493  *		add the specified prefix, filling hostid part from
1494  *		the first link-local address.  prefixlen must be <= 64.
1495  *	SIOCDLIFADDR: delete the specified address.
1496  *	SIOCDLIFADDR with IFLR_PREFIX:
1497  *		delete the first address that matches the specified prefix.
1498  * return values:
1499  *	EINVAL on invalid parameters
1500  *	EADDRNOTAVAIL on prefix match failed/specified address not found
1501  *	other values may be returned from in6_ioctl()
1502  *
1503  * NOTE: SIOCALIFADDR(with IFLR_PREFIX set) allows prefixlen less than 64.
1504  * this is to accommodate address naming scheme other than RFC2374,
1505  * in the future.
1506  * RFC2373 defines interface id to be 64bit, but it allows non-RFC2374
1507  * address encoding scheme. (see figure on page 8)
1508  */
1509 static int
1510 in6_lifaddr_ioctl(struct socket *so, u_long cmd, void *data,
1511 	struct ifnet *ifp, struct lwp *l)
1512 {
1513 	struct in6_ifaddr *ia;
1514 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
1515 	struct ifaddr *ifa;
1516 	struct sockaddr *sa;
1517 
1518 	/* sanity checks */
1519 	if (!data || !ifp) {
1520 		panic("invalid argument to in6_lifaddr_ioctl");
1521 		/* NOTREACHED */
1522 	}
1523 
1524 	switch (cmd) {
1525 	case SIOCGLIFADDR:
1526 		/* address must be specified on GET with IFLR_PREFIX */
1527 		if ((iflr->flags & IFLR_PREFIX) == 0)
1528 			break;
1529 		/* FALLTHROUGH */
1530 	case SIOCALIFADDR:
1531 	case SIOCDLIFADDR:
1532 		/* address must be specified on ADD and DELETE */
1533 		sa = (struct sockaddr *)&iflr->addr;
1534 		if (sa->sa_family != AF_INET6)
1535 			return EINVAL;
1536 		if (sa->sa_len != sizeof(struct sockaddr_in6))
1537 			return EINVAL;
1538 		/* XXX need improvement */
1539 		sa = (struct sockaddr *)&iflr->dstaddr;
1540 		if (sa->sa_family && sa->sa_family != AF_INET6)
1541 			return EINVAL;
1542 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in6))
1543 			return EINVAL;
1544 		break;
1545 	default: /* shouldn't happen */
1546 #if 0
1547 		panic("invalid cmd to in6_lifaddr_ioctl");
1548 		/* NOTREACHED */
1549 #else
1550 		return EOPNOTSUPP;
1551 #endif
1552 	}
1553 	if (sizeof(struct in6_addr) * NBBY < iflr->prefixlen)
1554 		return EINVAL;
1555 
1556 	switch (cmd) {
1557 	case SIOCALIFADDR:
1558 	    {
1559 		struct in6_aliasreq ifra;
1560 		struct in6_addr *xhostid = NULL;
1561 		int prefixlen;
1562 
1563 		if ((iflr->flags & IFLR_PREFIX) != 0) {
1564 			struct sockaddr_in6 *sin6;
1565 
1566 			/*
1567 			 * xhostid is to fill in the hostid part of the
1568 			 * address.  xhostid points to the first link-local
1569 			 * address attached to the interface.
1570 			 */
1571 			ia = in6ifa_ifpforlinklocal(ifp, 0);
1572 			if (ia == NULL)
1573 				return EADDRNOTAVAIL;
1574 			xhostid = IFA_IN6(&ia->ia_ifa);
1575 
1576 		 	/* prefixlen must be <= 64. */
1577 			if (64 < iflr->prefixlen)
1578 				return EINVAL;
1579 			prefixlen = iflr->prefixlen;
1580 
1581 			/* hostid part must be zero. */
1582 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1583 			if (sin6->sin6_addr.s6_addr32[2] != 0
1584 			 || sin6->sin6_addr.s6_addr32[3] != 0) {
1585 				return EINVAL;
1586 			}
1587 		} else
1588 			prefixlen = iflr->prefixlen;
1589 
1590 		/* copy args to in6_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
1591 		memset(&ifra, 0, sizeof(ifra));
1592 		memcpy(ifra.ifra_name, iflr->iflr_name, sizeof(ifra.ifra_name));
1593 
1594 		memcpy(&ifra.ifra_addr, &iflr->addr,
1595 		    ((struct sockaddr *)&iflr->addr)->sa_len);
1596 		if (xhostid) {
1597 			/* fill in hostid part */
1598 			ifra.ifra_addr.sin6_addr.s6_addr32[2] =
1599 			    xhostid->s6_addr32[2];
1600 			ifra.ifra_addr.sin6_addr.s6_addr32[3] =
1601 			    xhostid->s6_addr32[3];
1602 		}
1603 
1604 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) { /* XXX */
1605 			memcpy(&ifra.ifra_dstaddr, &iflr->dstaddr,
1606 			    ((struct sockaddr *)&iflr->dstaddr)->sa_len);
1607 			if (xhostid) {
1608 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[2] =
1609 				    xhostid->s6_addr32[2];
1610 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[3] =
1611 				    xhostid->s6_addr32[3];
1612 			}
1613 		}
1614 
1615 		ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
1616 		in6_prefixlen2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);
1617 
1618 		ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
1619 		ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
1620 		ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
1621 		return in6_control(so, SIOCAIFADDR_IN6, &ifra, ifp, l);
1622 	    }
1623 	case SIOCGLIFADDR:
1624 	case SIOCDLIFADDR:
1625 	    {
1626 		struct in6_addr mask, candidate, match;
1627 		struct sockaddr_in6 *sin6;
1628 		int cmp;
1629 
1630 		memset(&mask, 0, sizeof(mask));
1631 		if (iflr->flags & IFLR_PREFIX) {
1632 			/* lookup a prefix rather than address. */
1633 			in6_prefixlen2mask(&mask, iflr->prefixlen);
1634 
1635 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1636 			memcpy(&match, &sin6->sin6_addr, sizeof(match));
1637 			match.s6_addr32[0] &= mask.s6_addr32[0];
1638 			match.s6_addr32[1] &= mask.s6_addr32[1];
1639 			match.s6_addr32[2] &= mask.s6_addr32[2];
1640 			match.s6_addr32[3] &= mask.s6_addr32[3];
1641 
1642 			/* if you set extra bits, that's wrong */
1643 			if (memcmp(&match, &sin6->sin6_addr, sizeof(match)))
1644 				return EINVAL;
1645 
1646 			cmp = 1;
1647 		} else {
1648 			if (cmd == SIOCGLIFADDR) {
1649 				/* on getting an address, take the 1st match */
1650 				cmp = 0;	/* XXX */
1651 			} else {
1652 				/* on deleting an address, do exact match */
1653 				in6_prefixlen2mask(&mask, 128);
1654 				sin6 = (struct sockaddr_in6 *)&iflr->addr;
1655 				memcpy(&match, &sin6->sin6_addr, sizeof(match));
1656 
1657 				cmp = 1;
1658 			}
1659 		}
1660 
1661 		IFADDR_FOREACH(ifa, ifp) {
1662 			if (ifa->ifa_addr->sa_family != AF_INET6)
1663 				continue;
1664 			if (!cmp)
1665 				break;
1666 
1667 			/*
1668 			 * XXX: this is adhoc, but is necessary to allow
1669 			 * a user to specify fe80::/64 (not /10) for a
1670 			 * link-local address.
1671 			 */
1672 			memcpy(&candidate, IFA_IN6(ifa), sizeof(candidate));
1673 			in6_clearscope(&candidate);
1674 			candidate.s6_addr32[0] &= mask.s6_addr32[0];
1675 			candidate.s6_addr32[1] &= mask.s6_addr32[1];
1676 			candidate.s6_addr32[2] &= mask.s6_addr32[2];
1677 			candidate.s6_addr32[3] &= mask.s6_addr32[3];
1678 			if (IN6_ARE_ADDR_EQUAL(&candidate, &match))
1679 				break;
1680 		}
1681 		if (!ifa)
1682 			return EADDRNOTAVAIL;
1683 		ia = ifa2ia6(ifa);
1684 
1685 		if (cmd == SIOCGLIFADDR) {
1686 			int error;
1687 
1688 			/* fill in the if_laddrreq structure */
1689 			memcpy(&iflr->addr, &ia->ia_addr, ia->ia_addr.sin6_len);
1690 			error = sa6_recoverscope(
1691 			    (struct sockaddr_in6 *)&iflr->addr);
1692 			if (error != 0)
1693 				return error;
1694 
1695 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1696 				memcpy(&iflr->dstaddr, &ia->ia_dstaddr,
1697 				    ia->ia_dstaddr.sin6_len);
1698 				error = sa6_recoverscope(
1699 				    (struct sockaddr_in6 *)&iflr->dstaddr);
1700 				if (error != 0)
1701 					return error;
1702 			} else
1703 				memset(&iflr->dstaddr, 0, sizeof(iflr->dstaddr));
1704 
1705 			iflr->prefixlen =
1706 			    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
1707 
1708 			iflr->flags = ia->ia6_flags;	/* XXX */
1709 
1710 			return 0;
1711 		} else {
1712 			struct in6_aliasreq ifra;
1713 
1714 			/* fill in6_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
1715 			memset(&ifra, 0, sizeof(ifra));
1716 			memcpy(ifra.ifra_name, iflr->iflr_name,
1717 			    sizeof(ifra.ifra_name));
1718 
1719 			memcpy(&ifra.ifra_addr, &ia->ia_addr,
1720 			    ia->ia_addr.sin6_len);
1721 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1722 				memcpy(&ifra.ifra_dstaddr, &ia->ia_dstaddr,
1723 				    ia->ia_dstaddr.sin6_len);
1724 			} else {
1725 				memset(&ifra.ifra_dstaddr, 0,
1726 				    sizeof(ifra.ifra_dstaddr));
1727 			}
1728 			memcpy(&ifra.ifra_dstaddr, &ia->ia_prefixmask,
1729 			    ia->ia_prefixmask.sin6_len);
1730 
1731 			ifra.ifra_flags = ia->ia6_flags;
1732 			return in6_control(so, SIOCDIFADDR_IN6, &ifra, ifp, l);
1733 		}
1734 	    }
1735 	}
1736 
1737 	return EOPNOTSUPP;	/* just for safety */
1738 }
1739 
1740 /*
1741  * Initialize an interface's internet6 address
1742  * and routing table entry.
1743  */
1744 static int
1745 in6_ifinit(struct ifnet *ifp, struct in6_ifaddr *ia,
1746 	const struct sockaddr_in6 *sin6, int newhost)
1747 {
1748 	int	error = 0, plen, ifacount = 0;
1749 	int	s = splnet();
1750 	struct ifaddr *ifa;
1751 
1752 	/*
1753 	 * Give the interface a chance to initialize
1754 	 * if this is its first address,
1755 	 * and to validate the address if necessary.
1756 	 */
1757 	IFADDR_FOREACH(ifa, ifp) {
1758 		if (ifa->ifa_addr == NULL)
1759 			continue;	/* just for safety */
1760 		if (ifa->ifa_addr->sa_family != AF_INET6)
1761 			continue;
1762 		ifacount++;
1763 	}
1764 
1765 	ia->ia_addr = *sin6;
1766 
1767 	if (ifacount <= 1 &&
1768 	    (error = if_addr_init(ifp, &ia->ia_ifa, true)) != 0) {
1769 		splx(s);
1770 		return error;
1771 	}
1772 	splx(s);
1773 
1774 	ia->ia_ifa.ifa_metric = ifp->if_metric;
1775 
1776 	/* we could do in(6)_socktrim here, but just omit it at this moment. */
1777 
1778 	/*
1779 	 * Special case:
1780 	 * If the destination address is specified for a point-to-point
1781 	 * interface, install a route to the destination as an interface
1782 	 * direct route.
1783 	 */
1784 	plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
1785 	if (plen == 128 && ia->ia_dstaddr.sin6_family == AF_INET6) {
1786 		if ((error = rtinit(&ia->ia_ifa, RTM_ADD,
1787 				    RTF_UP | RTF_HOST)) != 0)
1788 			return error;
1789 		ia->ia_flags |= IFA_ROUTE;
1790 	}
1791 
1792 	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
1793 	if (newhost) {
1794 		/* set the rtrequest function to create llinfo */
1795 		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
1796 		in6_ifaddloop(&ia->ia_ifa);
1797 	} else {
1798 		/* Inform the routing socket of new flags/timings */
1799 		nd6_newaddrmsg(&ia->ia_ifa);
1800 	}
1801 
1802 	if (ifp->if_flags & IFF_MULTICAST)
1803 		in6_restoremkludge(ia, ifp);
1804 
1805 	return error;
1806 }
1807 
1808 static struct ifaddr *
1809 bestifa(struct ifaddr *best_ifa, struct ifaddr *ifa)
1810 {
1811 	if (best_ifa == NULL || best_ifa->ifa_preference < ifa->ifa_preference)
1812 		return ifa;
1813 	return best_ifa;
1814 }
1815 
1816 /*
1817  * Find an IPv6 interface link-local address specific to an interface.
1818  */
1819 struct in6_ifaddr *
1820 in6ifa_ifpforlinklocal(const struct ifnet *ifp, const int ignoreflags)
1821 {
1822 	struct ifaddr *best_ifa = NULL, *ifa;
1823 
1824 	IFADDR_FOREACH(ifa, ifp) {
1825 		if (ifa->ifa_addr == NULL)
1826 			continue;	/* just for safety */
1827 		if (ifa->ifa_addr->sa_family != AF_INET6)
1828 			continue;
1829 		if (!IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa)))
1830 			continue;
1831 		if ((((struct in6_ifaddr *)ifa)->ia6_flags & ignoreflags) != 0)
1832 			continue;
1833 		best_ifa = bestifa(best_ifa, ifa);
1834 	}
1835 
1836 	return (struct in6_ifaddr *)best_ifa;
1837 }
1838 
1839 
1840 /*
1841  * find the internet address corresponding to a given interface and address.
1842  */
1843 struct in6_ifaddr *
1844 in6ifa_ifpwithaddr(const struct ifnet *ifp, const struct in6_addr *addr)
1845 {
1846 	struct ifaddr *best_ifa = NULL, *ifa;
1847 
1848 	IFADDR_FOREACH(ifa, ifp) {
1849 		if (ifa->ifa_addr == NULL)
1850 			continue;	/* just for safety */
1851 		if (ifa->ifa_addr->sa_family != AF_INET6)
1852 			continue;
1853 		if (!IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa)))
1854 			continue;
1855 		best_ifa = bestifa(best_ifa, ifa);
1856 	}
1857 
1858 	return (struct in6_ifaddr *)best_ifa;
1859 }
1860 
1861 static struct in6_ifaddr *
1862 bestia(struct in6_ifaddr *best_ia, struct in6_ifaddr *ia)
1863 {
1864 	if (best_ia == NULL ||
1865 	    best_ia->ia_ifa.ifa_preference < ia->ia_ifa.ifa_preference)
1866 		return ia;
1867 	return best_ia;
1868 }
1869 
1870 /*
1871  * Convert IP6 address to printable (loggable) representation.
1872  */
1873 static int ip6round = 0;
1874 char *
1875 ip6_sprintf(const struct in6_addr *addr)
1876 {
1877 	static char ip6buf[8][48];
1878 	int i;
1879 	char *bp;
1880 	char *cp;
1881 	const u_int16_t *a = (const u_int16_t *)addr;
1882 	const u_int8_t *d;
1883 	int dcolon = 0;
1884 
1885 	ip6round = (ip6round + 1) & 7;
1886 	cp = ip6buf[ip6round];
1887 
1888 	for (i = 0; i < 8; i++) {
1889 		if (dcolon == 1) {
1890 			if (*a == 0) {
1891 				if (i == 7)
1892 					*cp++ = ':';
1893 				a++;
1894 				continue;
1895 			} else
1896 				dcolon = 2;
1897 		}
1898 		if (*a == 0) {
1899 			if (dcolon == 0 && *(a + 1) == 0) {
1900 				if (i == 0)
1901 					*cp++ = ':';
1902 				*cp++ = ':';
1903 				dcolon = 1;
1904 			} else {
1905 				*cp++ = '0';
1906 				*cp++ = ':';
1907 			}
1908 			a++;
1909 			continue;
1910 		}
1911 		d = (const u_char *)a;
1912 		bp = cp;
1913 		*cp = hexdigits[*d >> 4];
1914 		if (*cp != '0')
1915 			cp++;
1916 		*cp = hexdigits[*d++ & 0xf];
1917 		if (cp != bp || *cp != '0')
1918 			cp++;
1919 		*cp = hexdigits[*d >> 4];
1920 		if (cp != bp || *cp != '0')
1921 			cp++;
1922 		*cp++ = hexdigits[*d & 0xf];
1923 		*cp++ = ':';
1924 		a++;
1925 	}
1926 	*--cp = 0;
1927 	return ip6buf[ip6round];
1928 }
1929 
1930 /*
1931  * Determine if an address is on a local network.
1932  */
1933 int
1934 in6_localaddr(const struct in6_addr *in6)
1935 {
1936 	struct in6_ifaddr *ia;
1937 
1938 	if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6))
1939 		return 1;
1940 
1941 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
1942 		if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
1943 					      &ia->ia_prefixmask.sin6_addr))
1944 			return 1;
1945 
1946 	return 0;
1947 }
1948 
1949 int
1950 in6_is_addr_deprecated(struct sockaddr_in6 *sa6)
1951 {
1952 	struct in6_ifaddr *ia;
1953 
1954 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1955 		if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
1956 		    &sa6->sin6_addr) &&
1957 #ifdef SCOPEDROUTING
1958 		    ia->ia_addr.sin6_scope_id == sa6->sin6_scope_id &&
1959 #endif
1960 		    (ia->ia6_flags & IN6_IFF_DEPRECATED) != 0)
1961 			return 1; /* true */
1962 
1963 		/* XXX: do we still have to go thru the rest of the list? */
1964 	}
1965 
1966 	return 0;		/* false */
1967 }
1968 
1969 /*
1970  * return length of part which dst and src are equal
1971  * hard coding...
1972  */
1973 int
1974 in6_matchlen(struct in6_addr *src, struct in6_addr *dst)
1975 {
1976 	int match = 0;
1977 	u_char *s = (u_char *)src, *d = (u_char *)dst;
1978 	u_char *lim = s + 16, r;
1979 
1980 	while (s < lim)
1981 		if ((r = (*d++ ^ *s++)) != 0) {
1982 			while (r < 128) {
1983 				match++;
1984 				r <<= 1;
1985 			}
1986 			break;
1987 		} else
1988 			match += NBBY;
1989 	return match;
1990 }
1991 
1992 /* XXX: to be scope conscious */
1993 int
1994 in6_are_prefix_equal(struct in6_addr *p1, struct in6_addr *p2, int len)
1995 {
1996 	int bytelen, bitlen;
1997 
1998 	/* sanity check */
1999 	if (len < 0 || len > 128) {
2000 		log(LOG_ERR, "in6_are_prefix_equal: invalid prefix length(%d)\n",
2001 		    len);
2002 		return 0;
2003 	}
2004 
2005 	bytelen = len / NBBY;
2006 	bitlen = len % NBBY;
2007 
2008 	if (memcmp(&p1->s6_addr, &p2->s6_addr, bytelen))
2009 		return 0;
2010 	if (bitlen != 0 &&
2011 	    p1->s6_addr[bytelen] >> (NBBY - bitlen) !=
2012 	    p2->s6_addr[bytelen] >> (NBBY - bitlen))
2013 		return 0;
2014 
2015 	return 1;
2016 }
2017 
2018 void
2019 in6_prefixlen2mask(struct in6_addr *maskp, int len)
2020 {
2021 	static const u_char maskarray[NBBY] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
2022 	int bytelen, bitlen, i;
2023 
2024 	/* sanity check */
2025 	if (len < 0 || len > 128) {
2026 		log(LOG_ERR, "in6_prefixlen2mask: invalid prefix length(%d)\n",
2027 		    len);
2028 		return;
2029 	}
2030 
2031 	memset(maskp, 0, sizeof(*maskp));
2032 	bytelen = len / NBBY;
2033 	bitlen = len % NBBY;
2034 	for (i = 0; i < bytelen; i++)
2035 		maskp->s6_addr[i] = 0xff;
2036 	if (bitlen)
2037 		maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
2038 }
2039 
2040 /*
2041  * return the best address out of the same scope. if no address was
2042  * found, return the first valid address from designated IF.
2043  */
2044 struct in6_ifaddr *
2045 in6_ifawithifp(struct ifnet *ifp, struct in6_addr *dst)
2046 {
2047 	int dst_scope =	in6_addrscope(dst), blen = -1, tlen;
2048 	struct ifaddr *ifa;
2049 	struct in6_ifaddr *best_ia = NULL, *ia;
2050 	struct in6_ifaddr *dep[2];	/* last-resort: deprecated */
2051 
2052 	dep[0] = dep[1] = NULL;
2053 
2054 	/*
2055 	 * We first look for addresses in the same scope.
2056 	 * If there is one, return it.
2057 	 * If two or more, return one which matches the dst longest.
2058 	 * If none, return one of global addresses assigned other ifs.
2059 	 */
2060 	IFADDR_FOREACH(ifa, ifp) {
2061 		if (ifa->ifa_addr->sa_family != AF_INET6)
2062 			continue;
2063 		ia = (struct in6_ifaddr *)ifa;
2064 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2065 			continue; /* XXX: is there any case to allow anycast? */
2066 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2067 			continue; /* don't use this interface */
2068 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2069 			continue;
2070 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2071 			if (ip6_use_deprecated)
2072 				dep[0] = ia;
2073 			continue;
2074 		}
2075 
2076 		if (dst_scope != in6_addrscope(IFA_IN6(ifa)))
2077 			continue;
2078 		/*
2079 		 * call in6_matchlen() as few as possible
2080 		 */
2081 		if (best_ia == NULL) {
2082 			best_ia = ia;
2083 			continue;
2084 		}
2085 		if (blen == -1)
2086 			blen = in6_matchlen(&best_ia->ia_addr.sin6_addr, dst);
2087 		tlen = in6_matchlen(IFA_IN6(ifa), dst);
2088 		if (tlen > blen) {
2089 			blen = tlen;
2090 			best_ia = ia;
2091 		} else if (tlen == blen)
2092 			best_ia = bestia(best_ia, ia);
2093 	}
2094 	if (best_ia != NULL)
2095 		return best_ia;
2096 
2097 	IFADDR_FOREACH(ifa, ifp) {
2098 		if (ifa->ifa_addr->sa_family != AF_INET6)
2099 			continue;
2100 		ia = (struct in6_ifaddr *)ifa;
2101 		if (ia->ia6_flags & IN6_IFF_ANYCAST)
2102 			continue; /* XXX: is there any case to allow anycast? */
2103 		if (ia->ia6_flags & IN6_IFF_NOTREADY)
2104 			continue; /* don't use this interface */
2105 		if (ia->ia6_flags & IN6_IFF_DETACHED)
2106 			continue;
2107 		if (ia->ia6_flags & IN6_IFF_DEPRECATED) {
2108 			if (ip6_use_deprecated)
2109 				dep[1] = (struct in6_ifaddr *)ifa;
2110 			continue;
2111 		}
2112 
2113 		best_ia = bestia(best_ia, ia);
2114 	}
2115 	if (best_ia != NULL)
2116 		return best_ia;
2117 
2118 	/* use the last-resort values, that are, deprecated addresses */
2119 	if (dep[0])
2120 		return dep[0];
2121 	if (dep[1])
2122 		return dep[1];
2123 
2124 	return NULL;
2125 }
2126 
2127 /*
2128  * perform DAD when interface becomes IFF_UP.
2129  */
2130 void
2131 in6_if_link_up(struct ifnet *ifp)
2132 {
2133 	struct ifaddr *ifa;
2134 	struct in6_ifaddr *ia;
2135 
2136 	/* Ensure it's sane to run DAD */
2137 	if (ifp->if_link_state == LINK_STATE_DOWN)
2138 		return;
2139 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
2140 		return;
2141 
2142 	IFADDR_FOREACH(ifa, ifp) {
2143 		if (ifa->ifa_addr->sa_family != AF_INET6)
2144 			continue;
2145 		ia = (struct in6_ifaddr *)ifa;
2146 
2147 		/* If detached then mark as tentative */
2148 		if (ia->ia6_flags & IN6_IFF_DETACHED) {
2149 			ia->ia6_flags &= ~IN6_IFF_DETACHED;
2150 			if (in6if_do_dad(ifp)) {
2151 				ia->ia6_flags |= IN6_IFF_TENTATIVE;
2152 				nd6log((LOG_ERR, "in6_if_up: "
2153 				    "%s marked tentative\n",
2154 				    ip6_sprintf(&ia->ia_addr.sin6_addr)));
2155 			} else if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0)
2156 				nd6_newaddrmsg(ifa);
2157 		}
2158 
2159 		if (ia->ia6_flags & IN6_IFF_TENTATIVE) {
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 			nd6_dad_start(ifa,
2167 			    cprng_fast32() %
2168 				(MAX_RTR_SOLICITATION_DELAY * hz));
2169 		}
2170 	}
2171 
2172 	/* Restore any detached prefixes */
2173 	pfxlist_onlink_check();
2174 }
2175 
2176 void
2177 in6_if_up(struct ifnet *ifp)
2178 {
2179 
2180 	/*
2181 	 * special cases, like 6to4, are handled in in6_ifattach
2182 	 */
2183 	in6_ifattach(ifp, NULL);
2184 
2185 	/* interface may not support link state, so bring it up also */
2186 	in6_if_link_up(ifp);
2187 }
2188 /*
2189  * Mark all addresses as detached.
2190  */
2191 void
2192 in6_if_link_down(struct ifnet *ifp)
2193 {
2194 	struct ifaddr *ifa;
2195 	struct in6_ifaddr *ia;
2196 
2197 	/* Any prefixes on this interface should be detached as well */
2198 	pfxlist_onlink_check();
2199 
2200 	IFADDR_FOREACH(ifa, ifp) {
2201 		if (ifa->ifa_addr->sa_family != AF_INET6)
2202 			continue;
2203 		ia = (struct in6_ifaddr *)ifa;
2204 
2205 		/* Stop DAD processing */
2206 		nd6_dad_stop(ifa);
2207 
2208 		/*
2209 		 * Mark the address as detached.
2210 		 * This satisfies RFC4862 Section 5.3, but we should apply
2211 		 * this logic to all addresses to be a good citizen and
2212 		 * avoid potential duplicated addresses.
2213 		 * When the interface comes up again, detached addresses
2214 		 * are marked tentative and DAD commences.
2215 		 */
2216 		if (!(ia->ia6_flags & IN6_IFF_DETACHED)) {
2217 			nd6log((LOG_DEBUG, "in6_if_down: "
2218 			    "%s marked detached\n",
2219 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
2220 			ia->ia6_flags |= IN6_IFF_DETACHED;
2221 			ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
2222 			nd6_newaddrmsg(ifa);
2223 		}
2224 	}
2225 }
2226 
2227 void
2228 in6_if_down(struct ifnet *ifp)
2229 {
2230 
2231 	in6_if_link_down(ifp);
2232 }
2233 
2234 int
2235 in6if_do_dad(struct ifnet *ifp)
2236 {
2237 	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2238 		return 0;
2239 
2240 	switch (ifp->if_type) {
2241 	case IFT_FAITH:
2242 		/*
2243 		 * These interfaces do not have the IFF_LOOPBACK flag,
2244 		 * but loop packets back.  We do not have to do DAD on such
2245 		 * interfaces.  We should even omit it, because loop-backed
2246 		 * NS would confuse the DAD procedure.
2247 		 */
2248 		return 0;
2249 	default:
2250 		/*
2251 		 * Our DAD routine requires the interface up and running.
2252 		 * However, some interfaces can be up before the RUNNING
2253 		 * status.  Additionaly, users may try to assign addresses
2254 		 * before the interface becomes up (or running).
2255 		 * We simply skip DAD in such a case as a work around.
2256 		 * XXX: we should rather mark "tentative" on such addresses,
2257 		 * and do DAD after the interface becomes ready.
2258 		 */
2259 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
2260 		    (IFF_UP|IFF_RUNNING))
2261 			return 0;
2262 
2263 		return 1;
2264 	}
2265 }
2266 
2267 /*
2268  * Calculate max IPv6 MTU through all the interfaces and store it
2269  * to in6_maxmtu.
2270  */
2271 void
2272 in6_setmaxmtu(void)
2273 {
2274 	unsigned long maxmtu = 0;
2275 	struct ifnet *ifp;
2276 
2277 	IFNET_FOREACH(ifp) {
2278 		/* this function can be called during ifnet initialization */
2279 		if (!ifp->if_afdata[AF_INET6])
2280 			continue;
2281 		if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
2282 		    IN6_LINKMTU(ifp) > maxmtu)
2283 			maxmtu = IN6_LINKMTU(ifp);
2284 	}
2285 	if (maxmtu)	     /* update only when maxmtu is positive */
2286 		in6_maxmtu = maxmtu;
2287 }
2288 
2289 /*
2290  * Provide the length of interface identifiers to be used for the link attached
2291  * to the given interface.  The length should be defined in "IPv6 over
2292  * xxx-link" document.  Note that address architecture might also define
2293  * the length for a particular set of address prefixes, regardless of the
2294  * link type.  As clarified in rfc2462bis, those two definitions should be
2295  * consistent, and those really are as of August 2004.
2296  */
2297 int
2298 in6_if2idlen(struct ifnet *ifp)
2299 {
2300 	switch (ifp->if_type) {
2301 	case IFT_ETHER:		/* RFC2464 */
2302 	case IFT_PROPVIRTUAL:	/* XXX: no RFC. treat it as ether */
2303 	case IFT_L2VLAN:	/* ditto */
2304 	case IFT_IEEE80211:	/* ditto */
2305 	case IFT_FDDI:		/* RFC2467 */
2306 	case IFT_ISO88025:	/* RFC2470 (IPv6 over Token Ring) */
2307 	case IFT_PPP:		/* RFC2472 */
2308 	case IFT_ARCNET:	/* RFC2497 */
2309 	case IFT_FRELAY:	/* RFC2590 */
2310 	case IFT_IEEE1394:	/* RFC3146 */
2311 	case IFT_GIF:		/* draft-ietf-v6ops-mech-v2-07 */
2312 	case IFT_LOOP:		/* XXX: is this really correct? */
2313 		return 64;
2314 	default:
2315 		/*
2316 		 * Unknown link type:
2317 		 * It might be controversial to use the today's common constant
2318 		 * of 64 for these cases unconditionally.  For full compliance,
2319 		 * we should return an error in this case.  On the other hand,
2320 		 * if we simply miss the standard for the link type or a new
2321 		 * standard is defined for a new link type, the IFID length
2322 		 * is very likely to be the common constant.  As a compromise,
2323 		 * we always use the constant, but make an explicit notice
2324 		 * indicating the "unknown" case.
2325 		 */
2326 		printf("in6_if2idlen: unknown link type (%d)\n", ifp->if_type);
2327 		return 64;
2328 	}
2329 }
2330 
2331 void *
2332 in6_domifattach(struct ifnet *ifp)
2333 {
2334 	struct in6_ifextra *ext;
2335 
2336 	ext = malloc(sizeof(*ext), M_IFADDR, M_WAITOK|M_ZERO);
2337 
2338 	ext->in6_ifstat = malloc(sizeof(struct in6_ifstat),
2339 	    M_IFADDR, M_WAITOK|M_ZERO);
2340 
2341 	ext->icmp6_ifstat = malloc(sizeof(struct icmp6_ifstat),
2342 	    M_IFADDR, M_WAITOK|M_ZERO);
2343 
2344 	ext->nd_ifinfo = nd6_ifattach(ifp);
2345 	ext->scope6_id = scope6_ifattach(ifp);
2346 	ext->nprefixes = 0;
2347 	ext->ndefrouters = 0;
2348 	return ext;
2349 }
2350 
2351 void
2352 in6_domifdetach(struct ifnet *ifp, void *aux)
2353 {
2354 	struct in6_ifextra *ext = (struct in6_ifextra *)aux;
2355 
2356 	nd6_ifdetach(ext->nd_ifinfo);
2357 	free(ext->in6_ifstat, M_IFADDR);
2358 	free(ext->icmp6_ifstat, M_IFADDR);
2359 	scope6_ifdetach(ext->scope6_id);
2360 	free(ext, M_IFADDR);
2361 }
2362 
2363 /*
2364  * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
2365  * v4 mapped addr or v4 compat addr
2366  */
2367 void
2368 in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2369 {
2370 	memset(sin, 0, sizeof(*sin));
2371 	sin->sin_len = sizeof(struct sockaddr_in);
2372 	sin->sin_family = AF_INET;
2373 	sin->sin_port = sin6->sin6_port;
2374 	sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];
2375 }
2376 
2377 /* Convert sockaddr_in to sockaddr_in6 in v4 mapped addr format. */
2378 void
2379 in6_sin_2_v4mapsin6(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2380 {
2381 	memset(sin6, 0, sizeof(*sin6));
2382 	sin6->sin6_len = sizeof(struct sockaddr_in6);
2383 	sin6->sin6_family = AF_INET6;
2384 	sin6->sin6_port = sin->sin_port;
2385 	sin6->sin6_addr.s6_addr32[0] = 0;
2386 	sin6->sin6_addr.s6_addr32[1] = 0;
2387 	sin6->sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
2388 	sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;
2389 }
2390 
2391 /* Convert sockaddr_in6 into sockaddr_in. */
2392 void
2393 in6_sin6_2_sin_in_sock(struct sockaddr *nam)
2394 {
2395 	struct sockaddr_in *sin_p;
2396 	struct sockaddr_in6 sin6;
2397 
2398 	/*
2399 	 * Save original sockaddr_in6 addr and convert it
2400 	 * to sockaddr_in.
2401 	 */
2402 	sin6 = *(struct sockaddr_in6 *)nam;
2403 	sin_p = (struct sockaddr_in *)nam;
2404 	in6_sin6_2_sin(sin_p, &sin6);
2405 }
2406 
2407 /* Convert sockaddr_in into sockaddr_in6 in v4 mapped addr format. */
2408 void
2409 in6_sin_2_v4mapsin6_in_sock(struct sockaddr **nam)
2410 {
2411 	struct sockaddr_in *sin_p;
2412 	struct sockaddr_in6 *sin6_p;
2413 
2414 	sin6_p = malloc(sizeof(*sin6_p), M_SONAME, M_WAITOK);
2415 	sin_p = (struct sockaddr_in *)*nam;
2416 	in6_sin_2_v4mapsin6(sin_p, sin6_p);
2417 	free(*nam, M_SONAME);
2418 	*nam = (struct sockaddr *)sin6_p;
2419 }
2420