xref: /dragonfly/sys/netinet6/in6.c (revision 984263bc)
1 /*	$FreeBSD: src/sys/netinet6/in6.c,v 1.7.2.9 2002/04/28 05:40:26 suz Exp $	*/
2 /*	$KAME: in6.c,v 1.259 2002/01/21 11:37:50 keiichi 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. All advertising materials mentioning features or use of this software
46  *    must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Berkeley and its contributors.
49  * 4. Neither the name of the University nor the names of its contributors
50  *    may be used to endorse or promote products derived from this software
51  *    without specific prior written permission.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  *
65  *	@(#)in.c	8.2 (Berkeley) 11/15/93
66  */
67 
68 #include "opt_inet.h"
69 #include "opt_inet6.h"
70 
71 #include <sys/param.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 
83 #include <net/if.h>
84 #include <net/if_types.h>
85 #include <net/route.h>
86 #include <net/if_dl.h>
87 
88 #include <netinet/in.h>
89 #include <netinet/in_var.h>
90 #include <netinet/if_ether.h>
91 #ifndef SCOPEDROUTING
92 #include <netinet/in_systm.h>
93 #include <netinet/ip.h>
94 #include <netinet/in_pcb.h>
95 #endif
96 
97 #include <netinet/ip6.h>
98 #include <netinet6/ip6_var.h>
99 #include <netinet6/nd6.h>
100 #include <netinet6/mld6_var.h>
101 #include <netinet6/ip6_mroute.h>
102 #include <netinet6/in6_ifattach.h>
103 #include <netinet6/scope6_var.h>
104 #ifndef SCOPEDROUTING
105 #include <netinet6/in6_pcb.h>
106 #endif
107 
108 #include <net/net_osdep.h>
109 
110 MALLOC_DEFINE(M_IPMADDR, "in6_multi", "internet multicast address");
111 
112 /*
113  * Definitions of some costant IP6 addresses.
114  */
115 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
116 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
117 const struct in6_addr in6addr_nodelocal_allnodes =
118 	IN6ADDR_NODELOCAL_ALLNODES_INIT;
119 const struct in6_addr in6addr_linklocal_allnodes =
120 	IN6ADDR_LINKLOCAL_ALLNODES_INIT;
121 const struct in6_addr in6addr_linklocal_allrouters =
122 	IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
123 
124 const struct in6_addr in6mask0 = IN6MASK0;
125 const struct in6_addr in6mask32 = IN6MASK32;
126 const struct in6_addr in6mask64 = IN6MASK64;
127 const struct in6_addr in6mask96 = IN6MASK96;
128 const struct in6_addr in6mask128 = IN6MASK128;
129 
130 const struct sockaddr_in6 sa6_any = {sizeof(sa6_any), AF_INET6,
131 				     0, 0, IN6ADDR_ANY_INIT, 0};
132 
133 static int in6_lifaddr_ioctl __P((struct socket *, u_long, caddr_t,
134 	struct ifnet *, struct proc *));
135 static int in6_ifinit __P((struct ifnet *, struct in6_ifaddr *,
136 			   struct sockaddr_in6 *, int));
137 static void in6_unlink_ifa __P((struct in6_ifaddr *, struct ifnet *));
138 
139 struct in6_multihead in6_multihead;	/* XXX BSS initialization */
140 
141 int	(*faithprefix_p)(struct in6_addr *);
142 
143 /*
144  * Subroutine for in6_ifaddloop() and in6_ifremloop().
145  * This routine does actual work.
146  */
147 static void
148 in6_ifloop_request(int cmd, struct ifaddr *ifa)
149 {
150 	struct sockaddr_in6 all1_sa;
151 	struct rtentry *nrt = NULL;
152 	int e;
153 
154 	bzero(&all1_sa, sizeof(all1_sa));
155 	all1_sa.sin6_family = AF_INET6;
156 	all1_sa.sin6_len = sizeof(struct sockaddr_in6);
157 	all1_sa.sin6_addr = in6mask128;
158 
159 	/*
160 	 * We specify the address itself as the gateway, and set the
161 	 * RTF_LLINFO flag, so that the corresponding host route would have
162 	 * the flag, and thus applications that assume traditional behavior
163 	 * would be happy.  Note that we assume the caller of the function
164 	 * (probably implicitly) set nd6_rtrequest() to ifa->ifa_rtrequest,
165 	 * which changes the outgoing interface to the loopback interface.
166 	 */
167 	e = rtrequest(cmd, ifa->ifa_addr, ifa->ifa_addr,
168 		      (struct sockaddr *)&all1_sa,
169 		      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 		IFAFREE(nrt->rt_ifa);
187 		IFAREF(ifa);
188 		nrt->rt_ifa = ifa;
189 	}
190 
191 	/*
192 	 * Report the addition/removal of the address to the routing socket.
193 	 * XXX: since we called rtinit for a p2p interface with a destination,
194 	 *      we end up reporting twice in such a case.  Should we rather
195 	 *      omit the second report?
196 	 */
197 	if (nrt) {
198 		rt_newaddrmsg(cmd, ifa, e, nrt);
199 		if (cmd == RTM_DELETE) {
200 			if (nrt->rt_refcnt <= 0) {
201 				/* XXX: we should free the entry ourselves. */
202 				nrt->rt_refcnt++;
203 				rtfree(nrt);
204 			}
205 		} else {
206 			/* the cmd must be RTM_ADD here */
207 			nrt->rt_refcnt--;
208 		}
209 	}
210 }
211 
212 /*
213  * Add ownaddr as loopback rtentry.  We previously add the route only if
214  * necessary (ex. on a p2p link).  However, since we now manage addresses
215  * separately from prefixes, we should always add the route.  We can't
216  * rely on the cloning mechanism from the corresponding interface route
217  * any more.
218  */
219 static void
220 in6_ifaddloop(struct ifaddr *ifa)
221 {
222 	struct rtentry *rt;
223 
224 	/* If there is no loopback entry, allocate one. */
225 	rt = rtalloc1(ifa->ifa_addr, 0, 0);
226 	if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0 ||
227 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
228 		in6_ifloop_request(RTM_ADD, ifa);
229 	if (rt)
230 		rt->rt_refcnt--;
231 }
232 
233 /*
234  * Remove loopback rtentry of ownaddr generated by in6_ifaddloop(),
235  * if it exists.
236  */
237 static void
238 in6_ifremloop(struct ifaddr *ifa)
239 {
240 	struct in6_ifaddr *ia;
241 	struct rtentry *rt;
242 	int ia_count = 0;
243 
244 	/*
245 	 * Some of BSD variants do not remove cloned routes
246 	 * from an interface direct route, when removing the direct route
247 	 * (see comments in net/net_osdep.h).  Even for variants that do remove
248 	 * cloned routes, they could fail to remove the cloned routes when
249 	 * we handle multple addresses that share a common prefix.
250 	 * So, we should remove the route corresponding to the deleted address
251 	 * regardless of the result of in6_is_ifloop_auto().
252 	 */
253 
254 	/*
255 	 * Delete the entry only if exact one ifa exists.  More than one ifa
256 	 * can exist if we assign a same single address to multiple
257 	 * (probably p2p) interfaces.
258 	 * XXX: we should avoid such a configuration in IPv6...
259 	 */
260 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
261 		if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ia->ia_addr.sin6_addr)) {
262 			ia_count++;
263 			if (ia_count > 1)
264 				break;
265 		}
266 	}
267 
268 	if (ia_count == 1) {
269 		/*
270 		 * Before deleting, check if a corresponding loopbacked host
271 		 * route surely exists.  With this check, we can avoid to
272 		 * delete an interface direct route whose destination is same
273 		 * as the address being removed.  This can happen when remofing
274 		 * a subnet-router anycast address on an interface attahced
275 		 * to a shared medium.
276 		 */
277 		rt = rtalloc1(ifa->ifa_addr, 0, 0);
278 		if (rt != NULL && (rt->rt_flags & RTF_HOST) != 0 &&
279 		    (rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
280 			rt->rt_refcnt--;
281 			in6_ifloop_request(RTM_DELETE, ifa);
282 		}
283 	}
284 }
285 
286 int
287 in6_ifindex2scopeid(idx)
288 	int idx;
289 {
290 	struct ifnet *ifp;
291 	struct ifaddr *ifa;
292 	struct sockaddr_in6 *sin6;
293 
294 	if (idx < 0 || if_index < idx)
295 		return -1;
296 	ifp = ifindex2ifnet[idx];
297 
298 	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
299 	{
300 		if (ifa->ifa_addr->sa_family != AF_INET6)
301 			continue;
302 		sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
303 		if (IN6_IS_ADDR_SITELOCAL(&sin6->sin6_addr))
304 			return sin6->sin6_scope_id & 0xffff;
305 	}
306 
307 	return -1;
308 }
309 
310 int
311 in6_mask2len(mask, lim0)
312 	struct in6_addr *mask;
313 	u_char *lim0;
314 {
315 	int x = 0, y;
316 	u_char *lim = lim0, *p;
317 
318 	if (lim0 == NULL ||
319 	    lim0 - (u_char *)mask > sizeof(*mask)) /* ignore the scope_id part */
320 		lim = (u_char *)mask + sizeof(*mask);
321 	for (p = (u_char *)mask; p < lim; x++, p++) {
322 		if (*p != 0xff)
323 			break;
324 	}
325 	y = 0;
326 	if (p < lim) {
327 		for (y = 0; y < 8; y++) {
328 			if ((*p & (0x80 >> y)) == 0)
329 				break;
330 		}
331 	}
332 
333 	/*
334 	 * when the limit pointer is given, do a stricter check on the
335 	 * remaining bits.
336 	 */
337 	if (p < lim) {
338 		if (y != 0 && (*p & (0x00ff >> y)) != 0)
339 			return(-1);
340 		for (p = p + 1; p < lim; p++)
341 			if (*p != 0)
342 				return(-1);
343 	}
344 
345 	return x * 8 + y;
346 }
347 
348 void
349 in6_len2mask(mask, len)
350 	struct in6_addr *mask;
351 	int len;
352 {
353 	int i;
354 
355 	bzero(mask, sizeof(*mask));
356 	for (i = 0; i < len / 8; i++)
357 		mask->s6_addr8[i] = 0xff;
358 	if (len % 8)
359 		mask->s6_addr8[i] = (0xff00 >> (len % 8)) & 0xff;
360 }
361 
362 #define ifa2ia6(ifa)	((struct in6_ifaddr *)(ifa))
363 #define ia62ifa(ia6)	(&((ia6)->ia_ifa))
364 
365 int
366 in6_control(so, cmd, data, ifp, p)
367 	struct	socket *so;
368 	u_long cmd;
369 	caddr_t	data;
370 	struct ifnet *ifp;
371 	struct proc *p;
372 {
373 	struct	in6_ifreq *ifr = (struct in6_ifreq *)data;
374 	struct	in6_ifaddr *ia = NULL;
375 	struct	in6_aliasreq *ifra = (struct in6_aliasreq *)data;
376 	int privileged;
377 
378 	privileged = 0;
379 	if (p == NULL || !suser(p))
380 		privileged++;
381 
382 	switch (cmd) {
383 	case SIOCGETSGCNT_IN6:
384 	case SIOCGETMIFCNT_IN6:
385 		return (mrt6_ioctl(cmd, data));
386 	}
387 
388 	if (ifp == NULL)
389 		return(EOPNOTSUPP);
390 
391 	switch (cmd) {
392 	case SIOCSNDFLUSH_IN6:
393 	case SIOCSPFXFLUSH_IN6:
394 	case SIOCSRTRFLUSH_IN6:
395 	case SIOCSDEFIFACE_IN6:
396 	case SIOCSIFINFO_FLAGS:
397 		if (!privileged)
398 			return(EPERM);
399 		/* fall through */
400 	case OSIOCGIFINFO_IN6:
401 	case SIOCGIFINFO_IN6:
402 	case SIOCGDRLST_IN6:
403 	case SIOCGPRLST_IN6:
404 	case SIOCGNBRINFO_IN6:
405 	case SIOCGDEFIFACE_IN6:
406 		return(nd6_ioctl(cmd, data, ifp));
407 	}
408 
409 	switch (cmd) {
410 	case SIOCSIFPREFIX_IN6:
411 	case SIOCDIFPREFIX_IN6:
412 	case SIOCAIFPREFIX_IN6:
413 	case SIOCCIFPREFIX_IN6:
414 	case SIOCSGIFPREFIX_IN6:
415 	case SIOCGIFPREFIX_IN6:
416 		log(LOG_NOTICE,
417 		    "prefix ioctls are now invalidated. "
418 		    "please use ifconfig.\n");
419 		return(EOPNOTSUPP);
420 	}
421 
422 	switch (cmd) {
423 	case SIOCSSCOPE6:
424 		if (!privileged)
425 			return(EPERM);
426 		return(scope6_set(ifp, ifr->ifr_ifru.ifru_scope_id));
427 		break;
428 	case SIOCGSCOPE6:
429 		return(scope6_get(ifp, ifr->ifr_ifru.ifru_scope_id));
430 		break;
431 	case SIOCGSCOPE6DEF:
432 		return(scope6_get_default(ifr->ifr_ifru.ifru_scope_id));
433 		break;
434 	}
435 
436 	switch (cmd) {
437 	case SIOCALIFADDR:
438 	case SIOCDLIFADDR:
439 		if (!privileged)
440 			return(EPERM);
441 		/* fall through */
442 	case SIOCGLIFADDR:
443 		return in6_lifaddr_ioctl(so, cmd, data, ifp, p);
444 	}
445 
446 	/*
447 	 * Find address for this interface, if it exists.
448 	 */
449 	if (ifra->ifra_addr.sin6_family == AF_INET6) { /* XXX */
450 		struct sockaddr_in6 *sa6 =
451 			(struct sockaddr_in6 *)&ifra->ifra_addr;
452 
453 		if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) {
454 			if (sa6->sin6_addr.s6_addr16[1] == 0) {
455 				/* link ID is not embedded by the user */
456 				sa6->sin6_addr.s6_addr16[1] =
457 					htons(ifp->if_index);
458 			} else if (sa6->sin6_addr.s6_addr16[1] !=
459 				    htons(ifp->if_index)) {
460 				return(EINVAL);	/* link ID contradicts */
461 			}
462 			if (sa6->sin6_scope_id) {
463 				if (sa6->sin6_scope_id !=
464 				    (u_int32_t)ifp->if_index)
465 					return(EINVAL);
466 				sa6->sin6_scope_id = 0; /* XXX: good way? */
467 			}
468 		}
469 		ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr);
470 	}
471 
472 	switch (cmd) {
473 	case SIOCSIFADDR_IN6:
474 	case SIOCSIFDSTADDR_IN6:
475 	case SIOCSIFNETMASK_IN6:
476 		/*
477 		 * Since IPv6 allows a node to assign multiple addresses
478 		 * on a single interface, SIOCSIFxxx ioctls are not suitable
479 		 * and should be unused.
480 		 */
481 		/* we decided to obsolete this command (20000704) */
482 		return(EINVAL);
483 
484 	case SIOCDIFADDR_IN6:
485 		/*
486 		 * for IPv4, we look for existing in_ifaddr here to allow
487 		 * "ifconfig if0 delete" to remove first IPv4 address on the
488 		 * interface.  For IPv6, as the spec allow multiple interface
489 		 * address from the day one, we consider "remove the first one"
490 		 * semantics to be not preferable.
491 		 */
492 		if (ia == NULL)
493 			return(EADDRNOTAVAIL);
494 		/* FALLTHROUGH */
495 	case SIOCAIFADDR_IN6:
496 		/*
497 		 * We always require users to specify a valid IPv6 address for
498 		 * the corresponding operation.
499 		 */
500 		if (ifra->ifra_addr.sin6_family != AF_INET6 ||
501 		    ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6))
502 			return(EAFNOSUPPORT);
503 		if (!privileged)
504 			return(EPERM);
505 
506 		break;
507 
508 	case SIOCGIFADDR_IN6:
509 		/* This interface is basically deprecated. use SIOCGIFCONF. */
510 		/* fall through */
511 	case SIOCGIFAFLAG_IN6:
512 	case SIOCGIFNETMASK_IN6:
513 	case SIOCGIFDSTADDR_IN6:
514 	case SIOCGIFALIFETIME_IN6:
515 		/* must think again about its semantics */
516 		if (ia == NULL)
517 			return(EADDRNOTAVAIL);
518 		break;
519 	case SIOCSIFALIFETIME_IN6:
520 	    {
521 		struct in6_addrlifetime *lt;
522 
523 		if (!privileged)
524 			return(EPERM);
525 		if (ia == NULL)
526 			return(EADDRNOTAVAIL);
527 		/* sanity for overflow - beware unsigned */
528 		lt = &ifr->ifr_ifru.ifru_lifetime;
529 		if (lt->ia6t_vltime != ND6_INFINITE_LIFETIME
530 		 && lt->ia6t_vltime + time_second < time_second) {
531 			return EINVAL;
532 		}
533 		if (lt->ia6t_pltime != ND6_INFINITE_LIFETIME
534 		 && lt->ia6t_pltime + time_second < time_second) {
535 			return EINVAL;
536 		}
537 		break;
538 	    }
539 	}
540 
541 	switch (cmd) {
542 
543 	case SIOCGIFADDR_IN6:
544 		ifr->ifr_addr = ia->ia_addr;
545 		break;
546 
547 	case SIOCGIFDSTADDR_IN6:
548 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
549 			return(EINVAL);
550 		/*
551 		 * XXX: should we check if ifa_dstaddr is NULL and return
552 		 * an error?
553 		 */
554 		ifr->ifr_dstaddr = ia->ia_dstaddr;
555 		break;
556 
557 	case SIOCGIFNETMASK_IN6:
558 		ifr->ifr_addr = ia->ia_prefixmask;
559 		break;
560 
561 	case SIOCGIFAFLAG_IN6:
562 		ifr->ifr_ifru.ifru_flags6 = ia->ia6_flags;
563 		break;
564 
565 	case SIOCGIFSTAT_IN6:
566 		if (ifp == NULL)
567 			return EINVAL;
568 		if (in6_ifstat == NULL || ifp->if_index >= in6_ifstatmax
569 		 || in6_ifstat[ifp->if_index] == NULL) {
570 			/* return EAFNOSUPPORT? */
571 			bzero(&ifr->ifr_ifru.ifru_stat,
572 				sizeof(ifr->ifr_ifru.ifru_stat));
573 		} else
574 			ifr->ifr_ifru.ifru_stat = *in6_ifstat[ifp->if_index];
575 		break;
576 
577 	case SIOCGIFSTAT_ICMP6:
578 		if (ifp == NULL)
579 			return EINVAL;
580 		if (icmp6_ifstat == NULL || ifp->if_index >= icmp6_ifstatmax ||
581 		    icmp6_ifstat[ifp->if_index] == NULL) {
582 			/* return EAFNOSUPPORT? */
583 			bzero(&ifr->ifr_ifru.ifru_stat,
584 				sizeof(ifr->ifr_ifru.ifru_icmp6stat));
585 		} else
586 			ifr->ifr_ifru.ifru_icmp6stat =
587 				*icmp6_ifstat[ifp->if_index];
588 		break;
589 
590 	case SIOCGIFALIFETIME_IN6:
591 		ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
592 		break;
593 
594 	case SIOCSIFALIFETIME_IN6:
595 		ia->ia6_lifetime = ifr->ifr_ifru.ifru_lifetime;
596 		/* for sanity */
597 		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
598 			ia->ia6_lifetime.ia6t_expire =
599 				time_second + ia->ia6_lifetime.ia6t_vltime;
600 		} else
601 			ia->ia6_lifetime.ia6t_expire = 0;
602 		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
603 			ia->ia6_lifetime.ia6t_preferred =
604 				time_second + ia->ia6_lifetime.ia6t_pltime;
605 		} else
606 			ia->ia6_lifetime.ia6t_preferred = 0;
607 		break;
608 
609 	case SIOCAIFADDR_IN6:
610 	{
611 		int i, error = 0;
612 		struct nd_prefix pr0, *pr;
613 
614 		/*
615 		 * first, make or update the interface address structure,
616 		 * and link it to the list.
617 		 */
618 		if ((error = in6_update_ifa(ifp, ifra, ia)) != 0)
619 			return(error);
620 
621 		/*
622 		 * then, make the prefix on-link on the interface.
623 		 * XXX: we'd rather create the prefix before the address, but
624 		 * we need at least one address to install the corresponding
625 		 * interface route, so we configure the address first.
626 		 */
627 
628 		/*
629 		 * convert mask to prefix length (prefixmask has already
630 		 * been validated in in6_update_ifa().
631 		 */
632 		bzero(&pr0, sizeof(pr0));
633 		pr0.ndpr_ifp = ifp;
634 		pr0.ndpr_plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
635 					     NULL);
636 		if (pr0.ndpr_plen == 128)
637 			break;	/* we don't need to install a host route. */
638 		pr0.ndpr_prefix = ifra->ifra_addr;
639 		pr0.ndpr_mask = ifra->ifra_prefixmask.sin6_addr;
640 		/* apply the mask for safety. */
641 		for (i = 0; i < 4; i++) {
642 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
643 				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
644 		}
645 		/*
646 		 * XXX: since we don't have an API to set prefix (not address)
647 		 * lifetimes, we just use the same lifetimes as addresses.
648 		 * The (temporarily) installed lifetimes can be overridden by
649 		 * later advertised RAs (when accept_rtadv is non 0), which is
650 		 * an intended behavior.
651 		 */
652 		pr0.ndpr_raf_onlink = 1; /* should be configurable? */
653 		pr0.ndpr_raf_auto =
654 			((ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0);
655 		pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
656 		pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;
657 
658 		/* add the prefix if there's one. */
659 		if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
660 			/*
661 			 * nd6_prelist_add will install the corresponding
662 			 * interface route.
663 			 */
664 			if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
665 				return(error);
666 			if (pr == NULL) {
667 				log(LOG_ERR, "nd6_prelist_add succedded but "
668 				    "no prefix\n");
669 				return(EINVAL); /* XXX panic here? */
670 			}
671 		}
672 		if ((ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr))
673 		    == NULL) {
674 		    	/* XXX: this should not happen! */
675 			log(LOG_ERR, "in6_control: addition succeeded, but"
676 			    " no ifaddr\n");
677 		} else {
678 			if ((ia->ia6_flags & IN6_IFF_AUTOCONF) != 0 &&
679 			    ia->ia6_ndpr == NULL) { /* new autoconfed addr */
680 				ia->ia6_ndpr = pr;
681 				pr->ndpr_refcnt++;
682 
683 				/*
684 				 * If this is the first autoconf address from
685 				 * the prefix, create a temporary address
686 				 * as well (when specified).
687 				 */
688 				if (ip6_use_tempaddr &&
689 				    pr->ndpr_refcnt == 1) {
690 					int e;
691 					if ((e = in6_tmpifadd(ia, 1)) != 0) {
692 						log(LOG_NOTICE, "in6_control: "
693 						    "failed to create a "
694 						    "temporary address, "
695 						    "errno=%d\n",
696 						    e);
697 					}
698 				}
699 			}
700 
701 			/*
702 			 * this might affect the status of autoconfigured
703 			 * addresses, that is, this address might make
704 			 * other addresses detached.
705 			 */
706 			pfxlist_onlink_check();
707 		}
708 		break;
709 	}
710 
711 	case SIOCDIFADDR_IN6:
712 	{
713 		int i = 0;
714 		struct nd_prefix pr0, *pr;
715 
716 		/*
717 		 * If the address being deleted is the only one that owns
718 		 * the corresponding prefix, expire the prefix as well.
719 		 * XXX: theoretically, we don't have to warry about such
720 		 * relationship, since we separate the address management
721 		 * and the prefix management.  We do this, however, to provide
722 		 * as much backward compatibility as possible in terms of
723 		 * the ioctl operation.
724 		 */
725 		bzero(&pr0, sizeof(pr0));
726 		pr0.ndpr_ifp = ifp;
727 		pr0.ndpr_plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr,
728 					     NULL);
729 		if (pr0.ndpr_plen == 128)
730 			goto purgeaddr;
731 		pr0.ndpr_prefix = ia->ia_addr;
732 		pr0.ndpr_mask = ia->ia_prefixmask.sin6_addr;
733 		for (i = 0; i < 4; i++) {
734 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
735 				ia->ia_prefixmask.sin6_addr.s6_addr32[i];
736 		}
737 		/*
738 		 * The logic of the following condition is a bit complicated.
739 		 * We expire the prefix when
740 		 * 1. the address obeys autoconfiguration and it is the
741 		 *    only owner of the associated prefix, or
742 		 * 2. the address does not obey autoconf and there is no
743 		 *    other owner of the prefix.
744 		 */
745 		if ((pr = nd6_prefix_lookup(&pr0)) != NULL &&
746 		    (((ia->ia6_flags & IN6_IFF_AUTOCONF) != 0 &&
747 		      pr->ndpr_refcnt == 1) ||
748 		     ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0 &&
749 		      pr->ndpr_refcnt == 0))) {
750 			pr->ndpr_expire = 1; /* XXX: just for expiration */
751 		}
752 
753 	  purgeaddr:
754 		in6_purgeaddr(&ia->ia_ifa);
755 		break;
756 	}
757 
758 	default:
759 		if (ifp == NULL || ifp->if_ioctl == 0)
760 			return(EOPNOTSUPP);
761 		return((*ifp->if_ioctl)(ifp, cmd, data));
762 	}
763 
764 	return(0);
765 }
766 
767 /*
768  * Update parameters of an IPv6 interface address.
769  * If necessary, a new entry is created and linked into address chains.
770  * This function is separated from in6_control().
771  * XXX: should this be performed under splnet()?
772  */
773 int
774 in6_update_ifa(ifp, ifra, ia)
775 	struct ifnet *ifp;
776 	struct in6_aliasreq *ifra;
777 	struct in6_ifaddr *ia;
778 {
779 	int error = 0, hostIsNew = 0, plen = -1;
780 	struct in6_ifaddr *oia;
781 	struct sockaddr_in6 dst6;
782 	struct in6_addrlifetime *lt;
783 
784 	/* Validate parameters */
785 	if (ifp == NULL || ifra == NULL) /* this maybe redundant */
786 		return(EINVAL);
787 
788 	/*
789 	 * The destination address for a p2p link must have a family
790 	 * of AF_UNSPEC or AF_INET6.
791 	 */
792 	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
793 	    ifra->ifra_dstaddr.sin6_family != AF_INET6 &&
794 	    ifra->ifra_dstaddr.sin6_family != AF_UNSPEC)
795 		return(EAFNOSUPPORT);
796 	/*
797 	 * validate ifra_prefixmask.  don't check sin6_family, netmask
798 	 * does not carry fields other than sin6_len.
799 	 */
800 	if (ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6))
801 		return(EINVAL);
802 	/*
803 	 * Because the IPv6 address architecture is classless, we require
804 	 * users to specify a (non 0) prefix length (mask) for a new address.
805 	 * We also require the prefix (when specified) mask is valid, and thus
806 	 * reject a non-consecutive mask.
807 	 */
808 	if (ia == NULL && ifra->ifra_prefixmask.sin6_len == 0)
809 		return(EINVAL);
810 	if (ifra->ifra_prefixmask.sin6_len != 0) {
811 		plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
812 				    (u_char *)&ifra->ifra_prefixmask +
813 				    ifra->ifra_prefixmask.sin6_len);
814 		if (plen <= 0)
815 			return(EINVAL);
816 	}
817 	else {
818 		/*
819 		 * In this case, ia must not be NULL.  We just use its prefix
820 		 * length.
821 		 */
822 		plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
823 	}
824 	/*
825 	 * If the destination address on a p2p interface is specified,
826 	 * and the address is a scoped one, validate/set the scope
827 	 * zone identifier.
828 	 */
829 	dst6 = ifra->ifra_dstaddr;
830 	if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) &&
831 	    (dst6.sin6_family == AF_INET6)) {
832 		int scopeid;
833 
834 #ifndef SCOPEDROUTING
835 		if ((error = in6_recoverscope(&dst6,
836 					      &ifra->ifra_dstaddr.sin6_addr,
837 					      ifp)) != 0)
838 			return(error);
839 #endif
840 		scopeid = in6_addr2scopeid(ifp, &dst6.sin6_addr);
841 		if (dst6.sin6_scope_id == 0) /* user omit to specify the ID. */
842 			dst6.sin6_scope_id = scopeid;
843 		else if (dst6.sin6_scope_id != scopeid)
844 			return(EINVAL); /* scope ID mismatch. */
845 #ifndef SCOPEDROUTING
846 		if ((error = in6_embedscope(&dst6.sin6_addr, &dst6, NULL, NULL))
847 		    != 0)
848 			return(error);
849 		dst6.sin6_scope_id = 0; /* XXX */
850 #endif
851 	}
852 	/*
853 	 * The destination address can be specified only for a p2p or a
854 	 * loopback interface.  If specified, the corresponding prefix length
855 	 * must be 128.
856 	 */
857 	if (ifra->ifra_dstaddr.sin6_family == AF_INET6) {
858 		if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) == 0) {
859 			/* XXX: noisy message */
860 			log(LOG_INFO, "in6_update_ifa: a destination can be "
861 			    "specified for a p2p or a loopback IF only\n");
862 			return(EINVAL);
863 		}
864 		if (plen != 128) {
865 			/*
866 			 * The following message seems noisy, but we dare to
867 			 * add it for diagnosis.
868 			 */
869 			log(LOG_INFO, "in6_update_ifa: prefixlen must be 128 "
870 			    "when dstaddr is specified\n");
871 			return(EINVAL);
872 		}
873 	}
874 	/* lifetime consistency check */
875 	lt = &ifra->ifra_lifetime;
876 	if (lt->ia6t_vltime != ND6_INFINITE_LIFETIME
877 	    && lt->ia6t_vltime + time_second < time_second) {
878 		return EINVAL;
879 	}
880 	if (lt->ia6t_vltime == 0) {
881 		/*
882 		 * the following log might be noisy, but this is a typical
883 		 * configuration mistake or a tool's bug.
884 		 */
885 		log(LOG_INFO,
886 		    "in6_update_ifa: valid lifetime is 0 for %s\n",
887 		    ip6_sprintf(&ifra->ifra_addr.sin6_addr));
888 	}
889 	if (lt->ia6t_pltime != ND6_INFINITE_LIFETIME
890 	    && lt->ia6t_pltime + time_second < time_second) {
891 		return EINVAL;
892 	}
893 
894 	/*
895 	 * If this is a new address, allocate a new ifaddr and link it
896 	 * into chains.
897 	 */
898 	if (ia == NULL) {
899 		hostIsNew = 1;
900 		/*
901 		 * When in6_update_ifa() is called in a process of a received
902 		 * RA, it is called under splnet().  So, we should call malloc
903 		 * with M_NOWAIT.
904 		 */
905 		ia = (struct in6_ifaddr *)
906 			malloc(sizeof(*ia), M_IFADDR, M_NOWAIT);
907 		if (ia == NULL)
908 			return (ENOBUFS);
909 		bzero((caddr_t)ia, sizeof(*ia));
910 		/* Initialize the address and masks */
911 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
912 		ia->ia_addr.sin6_family = AF_INET6;
913 		ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
914 		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
915 			/*
916 			 * XXX: some functions expect that ifa_dstaddr is not
917 			 * NULL for p2p interfaces.
918 			 */
919 			ia->ia_ifa.ifa_dstaddr
920 				= (struct sockaddr *)&ia->ia_dstaddr;
921 		} else {
922 			ia->ia_ifa.ifa_dstaddr = NULL;
923 		}
924 		ia->ia_ifa.ifa_netmask
925 			= (struct sockaddr *)&ia->ia_prefixmask;
926 
927 		ia->ia_ifp = ifp;
928 		if ((oia = in6_ifaddr) != NULL) {
929 			for ( ; oia->ia_next; oia = oia->ia_next)
930 				continue;
931 			oia->ia_next = ia;
932 		} else
933 			in6_ifaddr = ia;
934 
935 		TAILQ_INSERT_TAIL(&ifp->if_addrlist, &ia->ia_ifa,
936 				  ifa_list);
937 	}
938 
939 	/* set prefix mask */
940 	if (ifra->ifra_prefixmask.sin6_len) {
941 		/*
942 		 * We prohibit changing the prefix length of an existing
943 		 * address, because
944 		 * + such an operation should be rare in IPv6, and
945 		 * + the operation would confuse prefix management.
946 		 */
947 		if (ia->ia_prefixmask.sin6_len &&
948 		    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL) != plen) {
949 			log(LOG_INFO, "in6_update_ifa: the prefix length of an"
950 			    " existing (%s) address should not be changed\n",
951 			    ip6_sprintf(&ia->ia_addr.sin6_addr));
952 			error = EINVAL;
953 			goto unlink;
954 		}
955 		ia->ia_prefixmask = ifra->ifra_prefixmask;
956 	}
957 
958 	/*
959 	 * If a new destination address is specified, scrub the old one and
960 	 * install the new destination.  Note that the interface must be
961 	 * p2p or loopback (see the check above.)
962 	 */
963 	if (dst6.sin6_family == AF_INET6 &&
964 	    !IN6_ARE_ADDR_EQUAL(&dst6.sin6_addr,
965 				&ia->ia_dstaddr.sin6_addr)) {
966 		int e;
967 
968 		if ((ia->ia_flags & IFA_ROUTE) != 0 &&
969 		    (e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
970 		    != 0) {
971 			log(LOG_ERR, "in6_update_ifa: failed to remove "
972 			    "a route to the old destination: %s\n",
973 			    ip6_sprintf(&ia->ia_addr.sin6_addr));
974 			/* proceed anyway... */
975 		}
976 		else
977 			ia->ia_flags &= ~IFA_ROUTE;
978 		ia->ia_dstaddr = dst6;
979 	}
980 
981 	/* reset the interface and routing table appropriately. */
982 	if ((error = in6_ifinit(ifp, ia, &ifra->ifra_addr, hostIsNew)) != 0)
983 		goto unlink;
984 
985 	/*
986 	 * Beyond this point, we should call in6_purgeaddr upon an error,
987 	 * not just go to unlink.
988 	 */
989 
990 #if 0				/* disable this mechanism for now */
991 	/* update prefix list */
992 	if (hostIsNew &&
993 	    (ifra->ifra_flags & IN6_IFF_NOPFX) == 0) { /* XXX */
994 		int iilen;
995 
996 		iilen = (sizeof(ia->ia_prefixmask.sin6_addr) << 3) - plen;
997 		if ((error = in6_prefix_add_ifid(iilen, ia)) != 0) {
998 			in6_purgeaddr((struct ifaddr *)ia);
999 			return(error);
1000 		}
1001 	}
1002 #endif
1003 
1004 	if ((ifp->if_flags & IFF_MULTICAST) != 0) {
1005 		struct sockaddr_in6 mltaddr, mltmask;
1006 		struct in6_multi *in6m;
1007 
1008 		if (hostIsNew) {
1009 			/*
1010 			 * join solicited multicast addr for new host id
1011 			 */
1012 			struct in6_addr llsol;
1013 			bzero(&llsol, sizeof(struct in6_addr));
1014 			llsol.s6_addr16[0] = htons(0xff02);
1015 			llsol.s6_addr16[1] = htons(ifp->if_index);
1016 			llsol.s6_addr32[1] = 0;
1017 			llsol.s6_addr32[2] = htonl(1);
1018 			llsol.s6_addr32[3] =
1019 				ifra->ifra_addr.sin6_addr.s6_addr32[3];
1020 			llsol.s6_addr8[12] = 0xff;
1021 			(void)in6_addmulti(&llsol, ifp, &error);
1022 			if (error != 0) {
1023 				log(LOG_WARNING,
1024 				    "in6_update_ifa: addmulti failed for "
1025 				    "%s on %s (errno=%d)\n",
1026 				    ip6_sprintf(&llsol), if_name(ifp),
1027 				    error);
1028 				in6_purgeaddr((struct ifaddr *)ia);
1029 				return(error);
1030 			}
1031 		}
1032 
1033 		bzero(&mltmask, sizeof(mltmask));
1034 		mltmask.sin6_len = sizeof(struct sockaddr_in6);
1035 		mltmask.sin6_family = AF_INET6;
1036 		mltmask.sin6_addr = in6mask32;
1037 
1038 		/*
1039 		 * join link-local all-nodes address
1040 		 */
1041 		bzero(&mltaddr, sizeof(mltaddr));
1042 		mltaddr.sin6_len = sizeof(struct sockaddr_in6);
1043 		mltaddr.sin6_family = AF_INET6;
1044 		mltaddr.sin6_addr = in6addr_linklocal_allnodes;
1045 		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
1046 
1047 		IN6_LOOKUP_MULTI(mltaddr.sin6_addr, ifp, in6m);
1048 		if (in6m == NULL) {
1049 			rtrequest(RTM_ADD,
1050 				  (struct sockaddr *)&mltaddr,
1051 				  (struct sockaddr *)&ia->ia_addr,
1052 				  (struct sockaddr *)&mltmask,
1053 				  RTF_UP|RTF_CLONING,  /* xxx */
1054 				  (struct rtentry **)0);
1055 			(void)in6_addmulti(&mltaddr.sin6_addr, ifp, &error);
1056 			if (error != 0) {
1057 				log(LOG_WARNING,
1058 				    "in6_update_ifa: addmulti failed for "
1059 				    "%s on %s (errno=%d)\n",
1060 				    ip6_sprintf(&mltaddr.sin6_addr),
1061 				    if_name(ifp), error);
1062 			}
1063 		}
1064 
1065 		/*
1066 		 * join node information group address
1067 		 */
1068 #define hostnamelen	strlen(hostname)
1069 		if (in6_nigroup(ifp, hostname, hostnamelen, &mltaddr.sin6_addr)
1070 		    == 0) {
1071 			IN6_LOOKUP_MULTI(mltaddr.sin6_addr, ifp, in6m);
1072 			if (in6m == NULL && ia != NULL) {
1073 				(void)in6_addmulti(&mltaddr.sin6_addr,
1074 				    ifp, &error);
1075 				if (error != 0) {
1076 					log(LOG_WARNING, "in6_update_ifa: "
1077 					    "addmulti failed for "
1078 					    "%s on %s (errno=%d)\n",
1079 					    ip6_sprintf(&mltaddr.sin6_addr),
1080 					    if_name(ifp), error);
1081 				}
1082 			}
1083 		}
1084 #undef hostnamelen
1085 
1086 		/*
1087 		 * join node-local all-nodes address, on loopback.
1088 		 * XXX: since "node-local" is obsoleted by interface-local,
1089 		 *      we have to join the group on every interface with
1090 		 *      some interface-boundary restriction.
1091 		 */
1092 		if (ifp->if_flags & IFF_LOOPBACK) {
1093 			struct in6_ifaddr *ia_loop;
1094 
1095 			struct in6_addr loop6 = in6addr_loopback;
1096 			ia_loop = in6ifa_ifpwithaddr(ifp, &loop6);
1097 
1098 			mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
1099 
1100 			IN6_LOOKUP_MULTI(mltaddr.sin6_addr, ifp, in6m);
1101 			if (in6m == NULL && ia_loop != NULL) {
1102 				rtrequest(RTM_ADD,
1103 					  (struct sockaddr *)&mltaddr,
1104 					  (struct sockaddr *)&ia_loop->ia_addr,
1105 					  (struct sockaddr *)&mltmask,
1106 					  RTF_UP,
1107 					  (struct rtentry **)0);
1108 				(void)in6_addmulti(&mltaddr.sin6_addr, ifp,
1109 						   &error);
1110 				if (error != 0) {
1111 					log(LOG_WARNING, "in6_update_ifa: "
1112 					    "addmulti failed for %s on %s "
1113 					    "(errno=%d)\n",
1114 					    ip6_sprintf(&mltaddr.sin6_addr),
1115 					    if_name(ifp), error);
1116 				}
1117 			}
1118 		}
1119 	}
1120 
1121 	ia->ia6_flags = ifra->ifra_flags;
1122 	ia->ia6_flags &= ~IN6_IFF_DUPLICATED;	/*safety*/
1123 	ia->ia6_flags &= ~IN6_IFF_NODAD;	/* Mobile IPv6 */
1124 
1125 	ia->ia6_lifetime = ifra->ifra_lifetime;
1126 	/* for sanity */
1127 	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
1128 		ia->ia6_lifetime.ia6t_expire =
1129 			time_second + ia->ia6_lifetime.ia6t_vltime;
1130 	} else
1131 		ia->ia6_lifetime.ia6t_expire = 0;
1132 	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
1133 		ia->ia6_lifetime.ia6t_preferred =
1134 			time_second + ia->ia6_lifetime.ia6t_pltime;
1135 	} else
1136 		ia->ia6_lifetime.ia6t_preferred = 0;
1137 
1138 	/*
1139 	 * make sure to initialize ND6 information.  this is to workaround
1140 	 * issues with interfaces with IPv6 addresses, which have never brought
1141 	 * up.  We are assuming that it is safe to nd6_ifattach multiple times.
1142 	 */
1143 	nd6_ifattach(ifp);
1144 
1145 	/*
1146 	 * Perform DAD, if needed.
1147 	 * XXX It may be of use, if we can administratively
1148 	 * disable DAD.
1149 	 */
1150 	if (in6if_do_dad(ifp) && (ifra->ifra_flags & IN6_IFF_NODAD) == 0) {
1151 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
1152 		nd6_dad_start((struct ifaddr *)ia, NULL);
1153 	}
1154 
1155 	return(error);
1156 
1157   unlink:
1158 	/*
1159 	 * XXX: if a change of an existing address failed, keep the entry
1160 	 * anyway.
1161 	 */
1162 	if (hostIsNew)
1163 		in6_unlink_ifa(ia, ifp);
1164 	return(error);
1165 }
1166 
1167 void
1168 in6_purgeaddr(ifa)
1169 	struct ifaddr *ifa;
1170 {
1171 	struct ifnet *ifp = ifa->ifa_ifp;
1172 	struct in6_ifaddr *ia = (struct in6_ifaddr *) ifa;
1173 
1174 	/* stop DAD processing */
1175 	nd6_dad_stop(ifa);
1176 
1177 	/*
1178 	 * delete route to the destination of the address being purged.
1179 	 * The interface must be p2p or loopback in this case.
1180 	 */
1181 	if ((ia->ia_flags & IFA_ROUTE) != 0 && ia->ia_dstaddr.sin6_len != 0) {
1182 		int e;
1183 
1184 		if ((e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
1185 		    != 0) {
1186 			log(LOG_ERR, "in6_purgeaddr: failed to remove "
1187 			    "a route to the p2p destination: %s on %s, "
1188 			    "errno=%d\n",
1189 			    ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
1190 			    e);
1191 			/* proceed anyway... */
1192 		}
1193 		else
1194 			ia->ia_flags &= ~IFA_ROUTE;
1195 	}
1196 
1197 	/* Remove ownaddr's loopback rtentry, if it exists. */
1198 	in6_ifremloop(&(ia->ia_ifa));
1199 
1200 	if (ifp->if_flags & IFF_MULTICAST) {
1201 		/*
1202 		 * delete solicited multicast addr for deleting host id
1203 		 */
1204 		struct in6_multi *in6m;
1205 		struct in6_addr llsol;
1206 		bzero(&llsol, sizeof(struct in6_addr));
1207 		llsol.s6_addr16[0] = htons(0xff02);
1208 		llsol.s6_addr16[1] = htons(ifp->if_index);
1209 		llsol.s6_addr32[1] = 0;
1210 		llsol.s6_addr32[2] = htonl(1);
1211 		llsol.s6_addr32[3] =
1212 			ia->ia_addr.sin6_addr.s6_addr32[3];
1213 		llsol.s6_addr8[12] = 0xff;
1214 
1215 		IN6_LOOKUP_MULTI(llsol, ifp, in6m);
1216 		if (in6m)
1217 			in6_delmulti(in6m);
1218 	}
1219 
1220 	in6_unlink_ifa(ia, ifp);
1221 }
1222 
1223 static void
1224 in6_unlink_ifa(ia, ifp)
1225 	struct in6_ifaddr *ia;
1226 	struct ifnet *ifp;
1227 {
1228 	int plen, iilen;
1229 	struct in6_ifaddr *oia;
1230 	int	s = splnet();
1231 
1232 	TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
1233 
1234 	oia = ia;
1235 	if (oia == (ia = in6_ifaddr))
1236 		in6_ifaddr = ia->ia_next;
1237 	else {
1238 		while (ia->ia_next && (ia->ia_next != oia))
1239 			ia = ia->ia_next;
1240 		if (ia->ia_next)
1241 			ia->ia_next = oia->ia_next;
1242 		else {
1243 			/* search failed */
1244 			printf("Couldn't unlink in6_ifaddr from in6_ifaddr\n");
1245 		}
1246 	}
1247 
1248 	if (oia->ia6_ifpr) {	/* check for safety */
1249 		plen = in6_mask2len(&oia->ia_prefixmask.sin6_addr, NULL);
1250 		iilen = (sizeof(oia->ia_prefixmask.sin6_addr) << 3) - plen;
1251 		in6_prefix_remove_ifid(iilen, oia);
1252 	}
1253 
1254 	/*
1255 	 * When an autoconfigured address is being removed, release the
1256 	 * reference to the base prefix.  Also, since the release might
1257 	 * affect the status of other (detached) addresses, call
1258 	 * pfxlist_onlink_check().
1259 	 */
1260 	if ((oia->ia6_flags & IN6_IFF_AUTOCONF) != 0) {
1261 		if (oia->ia6_ndpr == NULL) {
1262 			log(LOG_NOTICE, "in6_unlink_ifa: autoconf'ed address "
1263 			    "%p has no prefix\n", oia);
1264 		} else {
1265 			oia->ia6_ndpr->ndpr_refcnt--;
1266 			oia->ia6_flags &= ~IN6_IFF_AUTOCONF;
1267 			oia->ia6_ndpr = NULL;
1268 		}
1269 
1270 		pfxlist_onlink_check();
1271 	}
1272 
1273 	/*
1274 	 * release another refcnt for the link from in6_ifaddr.
1275 	 * Note that we should decrement the refcnt at least once for all *BSD.
1276 	 */
1277 	IFAFREE(&oia->ia_ifa);
1278 
1279 	splx(s);
1280 }
1281 
1282 void
1283 in6_purgeif(ifp)
1284 	struct ifnet *ifp;
1285 {
1286 	struct ifaddr *ifa, *nifa;
1287 
1288 	for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa != NULL; ifa = nifa)
1289 	{
1290 		nifa = TAILQ_NEXT(ifa, ifa_list);
1291 		if (ifa->ifa_addr->sa_family != AF_INET6)
1292 			continue;
1293 		in6_purgeaddr(ifa);
1294 	}
1295 
1296 	in6_ifdetach(ifp);
1297 }
1298 
1299 /*
1300  * SIOC[GAD]LIFADDR.
1301  *	SIOCGLIFADDR: get first address. (?)
1302  *	SIOCGLIFADDR with IFLR_PREFIX:
1303  *		get first address that matches the specified prefix.
1304  *	SIOCALIFADDR: add the specified address.
1305  *	SIOCALIFADDR with IFLR_PREFIX:
1306  *		add the specified prefix, filling hostid part from
1307  *		the first link-local address.  prefixlen must be <= 64.
1308  *	SIOCDLIFADDR: delete the specified address.
1309  *	SIOCDLIFADDR with IFLR_PREFIX:
1310  *		delete the first address that matches the specified prefix.
1311  * return values:
1312  *	EINVAL on invalid parameters
1313  *	EADDRNOTAVAIL on prefix match failed/specified address not found
1314  *	other values may be returned from in6_ioctl()
1315  *
1316  * NOTE: SIOCALIFADDR(with IFLR_PREFIX set) allows prefixlen less than 64.
1317  * this is to accomodate address naming scheme other than RFC2374,
1318  * in the future.
1319  * RFC2373 defines interface id to be 64bit, but it allows non-RFC2374
1320  * address encoding scheme. (see figure on page 8)
1321  */
1322 static int
1323 in6_lifaddr_ioctl(so, cmd, data, ifp, p)
1324 	struct socket *so;
1325 	u_long cmd;
1326 	caddr_t	data;
1327 	struct ifnet *ifp;
1328 	struct proc *p;
1329 {
1330 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
1331 	struct ifaddr *ifa;
1332 	struct sockaddr *sa;
1333 
1334 	/* sanity checks */
1335 	if (!data || !ifp) {
1336 		panic("invalid argument to in6_lifaddr_ioctl");
1337 		/*NOTRECHED*/
1338 	}
1339 
1340 	switch (cmd) {
1341 	case SIOCGLIFADDR:
1342 		/* address must be specified on GET with IFLR_PREFIX */
1343 		if ((iflr->flags & IFLR_PREFIX) == 0)
1344 			break;
1345 		/* FALLTHROUGH */
1346 	case SIOCALIFADDR:
1347 	case SIOCDLIFADDR:
1348 		/* address must be specified on ADD and DELETE */
1349 		sa = (struct sockaddr *)&iflr->addr;
1350 		if (sa->sa_family != AF_INET6)
1351 			return EINVAL;
1352 		if (sa->sa_len != sizeof(struct sockaddr_in6))
1353 			return EINVAL;
1354 		/* XXX need improvement */
1355 		sa = (struct sockaddr *)&iflr->dstaddr;
1356 		if (sa->sa_family && sa->sa_family != AF_INET6)
1357 			return EINVAL;
1358 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in6))
1359 			return EINVAL;
1360 		break;
1361 	default: /* shouldn't happen */
1362 #if 0
1363 		panic("invalid cmd to in6_lifaddr_ioctl");
1364 		/* NOTREACHED */
1365 #else
1366 		return EOPNOTSUPP;
1367 #endif
1368 	}
1369 	if (sizeof(struct in6_addr) * 8 < iflr->prefixlen)
1370 		return EINVAL;
1371 
1372 	switch (cmd) {
1373 	case SIOCALIFADDR:
1374 	    {
1375 		struct in6_aliasreq ifra;
1376 		struct in6_addr *hostid = NULL;
1377 		int prefixlen;
1378 
1379 		if ((iflr->flags & IFLR_PREFIX) != 0) {
1380 			struct sockaddr_in6 *sin6;
1381 
1382 			/*
1383 			 * hostid is to fill in the hostid part of the
1384 			 * address.  hostid points to the first link-local
1385 			 * address attached to the interface.
1386 			 */
1387 			ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0);
1388 			if (!ifa)
1389 				return EADDRNOTAVAIL;
1390 			hostid = IFA_IN6(ifa);
1391 
1392 		 	/* prefixlen must be <= 64. */
1393 			if (64 < iflr->prefixlen)
1394 				return EINVAL;
1395 			prefixlen = iflr->prefixlen;
1396 
1397 			/* hostid part must be zero. */
1398 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1399 			if (sin6->sin6_addr.s6_addr32[2] != 0
1400 			 || sin6->sin6_addr.s6_addr32[3] != 0) {
1401 				return EINVAL;
1402 			}
1403 		} else
1404 			prefixlen = iflr->prefixlen;
1405 
1406 		/* copy args to in6_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
1407 		bzero(&ifra, sizeof(ifra));
1408 		bcopy(iflr->iflr_name, ifra.ifra_name,
1409 			sizeof(ifra.ifra_name));
1410 
1411 		bcopy(&iflr->addr, &ifra.ifra_addr,
1412 			((struct sockaddr *)&iflr->addr)->sa_len);
1413 		if (hostid) {
1414 			/* fill in hostid part */
1415 			ifra.ifra_addr.sin6_addr.s6_addr32[2] =
1416 				hostid->s6_addr32[2];
1417 			ifra.ifra_addr.sin6_addr.s6_addr32[3] =
1418 				hostid->s6_addr32[3];
1419 		}
1420 
1421 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) {	/*XXX*/
1422 			bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
1423 				((struct sockaddr *)&iflr->dstaddr)->sa_len);
1424 			if (hostid) {
1425 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[2] =
1426 					hostid->s6_addr32[2];
1427 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[3] =
1428 					hostid->s6_addr32[3];
1429 			}
1430 		}
1431 
1432 		ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
1433 		in6_len2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);
1434 
1435 		ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
1436 		return in6_control(so, SIOCAIFADDR_IN6, (caddr_t)&ifra, ifp, p);
1437 	    }
1438 	case SIOCGLIFADDR:
1439 	case SIOCDLIFADDR:
1440 	    {
1441 		struct in6_ifaddr *ia;
1442 		struct in6_addr mask, candidate, match;
1443 		struct sockaddr_in6 *sin6;
1444 		int cmp;
1445 
1446 		bzero(&mask, sizeof(mask));
1447 		if (iflr->flags & IFLR_PREFIX) {
1448 			/* lookup a prefix rather than address. */
1449 			in6_len2mask(&mask, iflr->prefixlen);
1450 
1451 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1452 			bcopy(&sin6->sin6_addr, &match, sizeof(match));
1453 			match.s6_addr32[0] &= mask.s6_addr32[0];
1454 			match.s6_addr32[1] &= mask.s6_addr32[1];
1455 			match.s6_addr32[2] &= mask.s6_addr32[2];
1456 			match.s6_addr32[3] &= mask.s6_addr32[3];
1457 
1458 			/* if you set extra bits, that's wrong */
1459 			if (bcmp(&match, &sin6->sin6_addr, sizeof(match)))
1460 				return EINVAL;
1461 
1462 			cmp = 1;
1463 		} else {
1464 			if (cmd == SIOCGLIFADDR) {
1465 				/* on getting an address, take the 1st match */
1466 				cmp = 0;	/* XXX */
1467 			} else {
1468 				/* on deleting an address, do exact match */
1469 				in6_len2mask(&mask, 128);
1470 				sin6 = (struct sockaddr_in6 *)&iflr->addr;
1471 				bcopy(&sin6->sin6_addr, &match, sizeof(match));
1472 
1473 				cmp = 1;
1474 			}
1475 		}
1476 
1477 		TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
1478 		{
1479 			if (ifa->ifa_addr->sa_family != AF_INET6)
1480 				continue;
1481 			if (!cmp)
1482 				break;
1483 
1484 			bcopy(IFA_IN6(ifa), &candidate, sizeof(candidate));
1485 #ifndef SCOPEDROUTING
1486 			/*
1487 			 * XXX: this is adhoc, but is necessary to allow
1488 			 * a user to specify fe80::/64 (not /10) for a
1489 			 * link-local address.
1490 			 */
1491 			if (IN6_IS_ADDR_LINKLOCAL(&candidate))
1492 				candidate.s6_addr16[1] = 0;
1493 #endif
1494 			candidate.s6_addr32[0] &= mask.s6_addr32[0];
1495 			candidate.s6_addr32[1] &= mask.s6_addr32[1];
1496 			candidate.s6_addr32[2] &= mask.s6_addr32[2];
1497 			candidate.s6_addr32[3] &= mask.s6_addr32[3];
1498 			if (IN6_ARE_ADDR_EQUAL(&candidate, &match))
1499 				break;
1500 		}
1501 		if (!ifa)
1502 			return EADDRNOTAVAIL;
1503 		ia = ifa2ia6(ifa);
1504 
1505 		if (cmd == SIOCGLIFADDR) {
1506 #ifndef SCOPEDROUTING
1507 			struct sockaddr_in6 *s6;
1508 #endif
1509 
1510 			/* fill in the if_laddrreq structure */
1511 			bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin6_len);
1512 #ifndef SCOPEDROUTING		/* XXX see above */
1513 			s6 = (struct sockaddr_in6 *)&iflr->addr;
1514 			if (IN6_IS_ADDR_LINKLOCAL(&s6->sin6_addr)) {
1515 				s6->sin6_addr.s6_addr16[1] = 0;
1516 				s6->sin6_scope_id =
1517 					in6_addr2scopeid(ifp, &s6->sin6_addr);
1518 			}
1519 #endif
1520 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1521 				bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
1522 					ia->ia_dstaddr.sin6_len);
1523 #ifndef SCOPEDROUTING		/* XXX see above */
1524 				s6 = (struct sockaddr_in6 *)&iflr->dstaddr;
1525 				if (IN6_IS_ADDR_LINKLOCAL(&s6->sin6_addr)) {
1526 					s6->sin6_addr.s6_addr16[1] = 0;
1527 					s6->sin6_scope_id =
1528 						in6_addr2scopeid(ifp,
1529 								 &s6->sin6_addr);
1530 				}
1531 #endif
1532 			} else
1533 				bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
1534 
1535 			iflr->prefixlen =
1536 				in6_mask2len(&ia->ia_prefixmask.sin6_addr,
1537 					     NULL);
1538 
1539 			iflr->flags = ia->ia6_flags;	/* XXX */
1540 
1541 			return 0;
1542 		} else {
1543 			struct in6_aliasreq ifra;
1544 
1545 			/* fill in6_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
1546 			bzero(&ifra, sizeof(ifra));
1547 			bcopy(iflr->iflr_name, ifra.ifra_name,
1548 				sizeof(ifra.ifra_name));
1549 
1550 			bcopy(&ia->ia_addr, &ifra.ifra_addr,
1551 				ia->ia_addr.sin6_len);
1552 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1553 				bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
1554 					ia->ia_dstaddr.sin6_len);
1555 			} else {
1556 				bzero(&ifra.ifra_dstaddr,
1557 				    sizeof(ifra.ifra_dstaddr));
1558 			}
1559 			bcopy(&ia->ia_prefixmask, &ifra.ifra_dstaddr,
1560 				ia->ia_prefixmask.sin6_len);
1561 
1562 			ifra.ifra_flags = ia->ia6_flags;
1563 			return in6_control(so, SIOCDIFADDR_IN6, (caddr_t)&ifra,
1564 				ifp, p);
1565 		}
1566 	    }
1567 	}
1568 
1569 	return EOPNOTSUPP;	/* just for safety */
1570 }
1571 
1572 /*
1573  * Initialize an interface's intetnet6 address
1574  * and routing table entry.
1575  */
1576 static int
1577 in6_ifinit(ifp, ia, sin6, newhost)
1578 	struct ifnet *ifp;
1579 	struct in6_ifaddr *ia;
1580 	struct sockaddr_in6 *sin6;
1581 	int newhost;
1582 {
1583 	int	error = 0, plen, ifacount = 0;
1584 	int	s = splimp();
1585 	struct ifaddr *ifa;
1586 
1587 	/*
1588 	 * Give the interface a chance to initialize
1589 	 * if this is its first address,
1590 	 * and to validate the address if necessary.
1591 	 */
1592 	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
1593 	{
1594 		if (ifa->ifa_addr == NULL)
1595 			continue;	/* just for safety */
1596 		if (ifa->ifa_addr->sa_family != AF_INET6)
1597 			continue;
1598 		ifacount++;
1599 	}
1600 
1601 	ia->ia_addr = *sin6;
1602 
1603 	if (ifacount <= 1 && ifp->if_ioctl &&
1604 	    (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
1605 		splx(s);
1606 		return(error);
1607 	}
1608 	splx(s);
1609 
1610 	ia->ia_ifa.ifa_metric = ifp->if_metric;
1611 
1612 	/* we could do in(6)_socktrim here, but just omit it at this moment. */
1613 
1614 	/*
1615 	 * Special case:
1616 	 * If the destination address is specified for a point-to-point
1617 	 * interface, install a route to the destination as an interface
1618 	 * direct route.
1619 	 */
1620 	plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
1621 	if (plen == 128 && ia->ia_dstaddr.sin6_family == AF_INET6) {
1622 		if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD,
1623 				    RTF_UP | RTF_HOST)) != 0)
1624 			return(error);
1625 		ia->ia_flags |= IFA_ROUTE;
1626 	}
1627 	if (plen < 128) {
1628 		/*
1629 		 * The RTF_CLONING flag is necessary for in6_is_ifloop_auto().
1630 		 */
1631 		ia->ia_ifa.ifa_flags |= RTF_CLONING;
1632 	}
1633 
1634 	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
1635 	if (newhost) {
1636 		/* set the rtrequest function to create llinfo */
1637 		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
1638 		in6_ifaddloop(&(ia->ia_ifa));
1639 	}
1640 
1641 	return(error);
1642 }
1643 
1644 /*
1645  * Add an address to the list of IP6 multicast addresses for a
1646  * given interface.
1647  */
1648 struct	in6_multi *
1649 in6_addmulti(maddr6, ifp, errorp)
1650 	struct in6_addr *maddr6;
1651 	struct ifnet *ifp;
1652 	int *errorp;
1653 {
1654 	struct	in6_multi *in6m;
1655 	struct sockaddr_in6 sin6;
1656 	struct ifmultiaddr *ifma;
1657 	int	s = splnet();
1658 
1659 	*errorp = 0;
1660 
1661 	/*
1662 	 * Call generic routine to add membership or increment
1663 	 * refcount.  It wants addresses in the form of a sockaddr,
1664 	 * so we build one here (being careful to zero the unused bytes).
1665 	 */
1666 	bzero(&sin6, sizeof sin6);
1667 	sin6.sin6_family = AF_INET6;
1668 	sin6.sin6_len = sizeof sin6;
1669 	sin6.sin6_addr = *maddr6;
1670 	*errorp = if_addmulti(ifp, (struct sockaddr *)&sin6, &ifma);
1671 	if (*errorp) {
1672 		splx(s);
1673 		return 0;
1674 	}
1675 
1676 	/*
1677 	 * If ifma->ifma_protospec is null, then if_addmulti() created
1678 	 * a new record.  Otherwise, we are done.
1679 	 */
1680 	if (ifma->ifma_protospec != 0)
1681 		return ifma->ifma_protospec;
1682 
1683 	/* XXX - if_addmulti uses M_WAITOK.  Can this really be called
1684 	   at interrupt time?  If so, need to fix if_addmulti. XXX */
1685 	in6m = (struct in6_multi *)malloc(sizeof(*in6m), M_IPMADDR, M_NOWAIT);
1686 	if (in6m == NULL) {
1687 		splx(s);
1688 		return (NULL);
1689 	}
1690 
1691 	bzero(in6m, sizeof *in6m);
1692 	in6m->in6m_addr = *maddr6;
1693 	in6m->in6m_ifp = ifp;
1694 	in6m->in6m_ifma = ifma;
1695 	ifma->ifma_protospec = in6m;
1696 	LIST_INSERT_HEAD(&in6_multihead, in6m, in6m_entry);
1697 
1698 	/*
1699 	 * Let MLD6 know that we have joined a new IP6 multicast
1700 	 * group.
1701 	 */
1702 	mld6_start_listening(in6m);
1703 	splx(s);
1704 	return(in6m);
1705 }
1706 
1707 /*
1708  * Delete a multicast address record.
1709  */
1710 void
1711 in6_delmulti(in6m)
1712 	struct in6_multi *in6m;
1713 {
1714 	struct ifmultiaddr *ifma = in6m->in6m_ifma;
1715 	int	s = splnet();
1716 
1717 	if (ifma->ifma_refcount == 1) {
1718 		/*
1719 		 * No remaining claims to this record; let MLD6 know
1720 		 * that we are leaving the multicast group.
1721 		 */
1722 		mld6_stop_listening(in6m);
1723 		ifma->ifma_protospec = 0;
1724 		LIST_REMOVE(in6m, in6m_entry);
1725 		free(in6m, M_IPMADDR);
1726 	}
1727 	/* XXX - should be separate API for when we have an ifma? */
1728 	if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
1729 	splx(s);
1730 }
1731 
1732 /*
1733  * Find an IPv6 interface link-local address specific to an interface.
1734  */
1735 struct in6_ifaddr *
1736 in6ifa_ifpforlinklocal(ifp, ignoreflags)
1737 	struct ifnet *ifp;
1738 	int ignoreflags;
1739 {
1740 	struct ifaddr *ifa;
1741 
1742 	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
1743 	{
1744 		if (ifa->ifa_addr == NULL)
1745 			continue;	/* just for safety */
1746 		if (ifa->ifa_addr->sa_family != AF_INET6)
1747 			continue;
1748 		if (IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa))) {
1749 			if ((((struct in6_ifaddr *)ifa)->ia6_flags &
1750 			     ignoreflags) != 0)
1751 				continue;
1752 			break;
1753 		}
1754 	}
1755 
1756 	return((struct in6_ifaddr *)ifa);
1757 }
1758 
1759 
1760 /*
1761  * find the internet address corresponding to a given interface and address.
1762  */
1763 struct in6_ifaddr *
1764 in6ifa_ifpwithaddr(ifp, addr)
1765 	struct ifnet *ifp;
1766 	struct in6_addr *addr;
1767 {
1768 	struct ifaddr *ifa;
1769 
1770 	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
1771 	{
1772 		if (ifa->ifa_addr == NULL)
1773 			continue;	/* just for safety */
1774 		if (ifa->ifa_addr->sa_family != AF_INET6)
1775 			continue;
1776 		if (IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa)))
1777 			break;
1778 	}
1779 
1780 	return((struct in6_ifaddr *)ifa);
1781 }
1782 
1783 /*
1784  * Convert IP6 address to printable (loggable) representation.
1785  */
1786 static char digits[] = "0123456789abcdef";
1787 static int ip6round = 0;
1788 char *
1789 ip6_sprintf(addr)
1790 	const struct in6_addr *addr;
1791 {
1792 	static char ip6buf[8][48];
1793 	int i;
1794 	char *cp;
1795 	u_short *a = (u_short *)addr;
1796 	u_char *d;
1797 	int dcolon = 0;
1798 
1799 	ip6round = (ip6round + 1) & 7;
1800 	cp = ip6buf[ip6round];
1801 
1802 	for (i = 0; i < 8; i++) {
1803 		if (dcolon == 1) {
1804 			if (*a == 0) {
1805 				if (i == 7)
1806 					*cp++ = ':';
1807 				a++;
1808 				continue;
1809 			} else
1810 				dcolon = 2;
1811 		}
1812 		if (*a == 0) {
1813 			if (dcolon == 0 && *(a + 1) == 0) {
1814 				if (i == 0)
1815 					*cp++ = ':';
1816 				*cp++ = ':';
1817 				dcolon = 1;
1818 			} else {
1819 				*cp++ = '0';
1820 				*cp++ = ':';
1821 			}
1822 			a++;
1823 			continue;
1824 		}
1825 		d = (u_char *)a;
1826 		*cp++ = digits[*d >> 4];
1827 		*cp++ = digits[*d++ & 0xf];
1828 		*cp++ = digits[*d >> 4];
1829 		*cp++ = digits[*d & 0xf];
1830 		*cp++ = ':';
1831 		a++;
1832 	}
1833 	*--cp = 0;
1834 	return(ip6buf[ip6round]);
1835 }
1836 
1837 int
1838 in6_localaddr(in6)
1839 	struct in6_addr *in6;
1840 {
1841 	struct in6_ifaddr *ia;
1842 
1843 	if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6))
1844 		return 1;
1845 
1846 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
1847 		if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
1848 					      &ia->ia_prefixmask.sin6_addr))
1849 			return 1;
1850 
1851 	return (0);
1852 }
1853 
1854 int
1855 in6_is_addr_deprecated(sa6)
1856 	struct sockaddr_in6 *sa6;
1857 {
1858 	struct in6_ifaddr *ia;
1859 
1860 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1861 		if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
1862 				       &sa6->sin6_addr) &&
1863 #ifdef SCOPEDROUTING
1864 		    ia->ia_addr.sin6_scope_id == sa6->sin6_scope_id &&
1865 #endif
1866 		    (ia->ia6_flags & IN6_IFF_DEPRECATED) != 0)
1867 			return(1); /* true */
1868 
1869 		/* XXX: do we still have to go thru the rest of the list? */
1870 	}
1871 
1872 	return(0);		/* false */
1873 }
1874 
1875 /*
1876  * return length of part which dst and src are equal
1877  * hard coding...
1878  */
1879 int
1880 in6_matchlen(src, dst)
1881 struct in6_addr *src, *dst;
1882 {
1883 	int match = 0;
1884 	u_char *s = (u_char *)src, *d = (u_char *)dst;
1885 	u_char *lim = s + 16, r;
1886 
1887 	while (s < lim)
1888 		if ((r = (*d++ ^ *s++)) != 0) {
1889 			while (r < 128) {
1890 				match++;
1891 				r <<= 1;
1892 			}
1893 			break;
1894 		} else
1895 			match += 8;
1896 	return match;
1897 }
1898 
1899 /* XXX: to be scope conscious */
1900 int
1901 in6_are_prefix_equal(p1, p2, len)
1902 	struct in6_addr *p1, *p2;
1903 	int len;
1904 {
1905 	int bytelen, bitlen;
1906 
1907 	/* sanity check */
1908 	if (0 > len || len > 128) {
1909 		log(LOG_ERR, "in6_are_prefix_equal: invalid prefix length(%d)\n",
1910 		    len);
1911 		return(0);
1912 	}
1913 
1914 	bytelen = len / 8;
1915 	bitlen = len % 8;
1916 
1917 	if (bcmp(&p1->s6_addr, &p2->s6_addr, bytelen))
1918 		return(0);
1919 	if (p1->s6_addr[bytelen] >> (8 - bitlen) !=
1920 	    p2->s6_addr[bytelen] >> (8 - bitlen))
1921 		return(0);
1922 
1923 	return(1);
1924 }
1925 
1926 void
1927 in6_prefixlen2mask(maskp, len)
1928 	struct in6_addr *maskp;
1929 	int len;
1930 {
1931 	u_char maskarray[8] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
1932 	int bytelen, bitlen, i;
1933 
1934 	/* sanity check */
1935 	if (0 > len || len > 128) {
1936 		log(LOG_ERR, "in6_prefixlen2mask: invalid prefix length(%d)\n",
1937 		    len);
1938 		return;
1939 	}
1940 
1941 	bzero(maskp, sizeof(*maskp));
1942 	bytelen = len / 8;
1943 	bitlen = len % 8;
1944 	for (i = 0; i < bytelen; i++)
1945 		maskp->s6_addr[i] = 0xff;
1946 	if (bitlen)
1947 		maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
1948 }
1949 
1950 /*
1951  * return the best address out of the same scope
1952  */
1953 struct in6_ifaddr *
1954 in6_ifawithscope(oifp, dst)
1955 	struct ifnet *oifp;
1956 	struct in6_addr *dst;
1957 {
1958 	int dst_scope =	in6_addrscope(dst), src_scope, best_scope = 0;
1959 	int blen = -1;
1960 	struct ifaddr *ifa;
1961 	struct ifnet *ifp;
1962 	struct in6_ifaddr *ifa_best = NULL;
1963 
1964 	if (oifp == NULL) {
1965 #if 0
1966 		printf("in6_ifawithscope: output interface is not specified\n");
1967 #endif
1968 		return(NULL);
1969 	}
1970 
1971 	/*
1972 	 * We search for all addresses on all interfaces from the beginning.
1973 	 * Comparing an interface with the outgoing interface will be done
1974 	 * only at the final stage of tiebreaking.
1975 	 */
1976 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
1977 	{
1978 		/*
1979 		 * We can never take an address that breaks the scope zone
1980 		 * of the destination.
1981 		 */
1982 		if (in6_addr2scopeid(ifp, dst) != in6_addr2scopeid(oifp, dst))
1983 			continue;
1984 
1985 		TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
1986 		{
1987 			int tlen = -1, dscopecmp, bscopecmp, matchcmp;
1988 
1989 			if (ifa->ifa_addr->sa_family != AF_INET6)
1990 				continue;
1991 
1992 			src_scope = in6_addrscope(IFA_IN6(ifa));
1993 
1994 			/*
1995 			 * Don't use an address before completing DAD
1996 			 * nor a duplicated address.
1997 			 */
1998 			if (((struct in6_ifaddr *)ifa)->ia6_flags &
1999 			    IN6_IFF_NOTREADY)
2000 				continue;
2001 
2002 			/* XXX: is there any case to allow anycasts? */
2003 			if (((struct in6_ifaddr *)ifa)->ia6_flags &
2004 			    IN6_IFF_ANYCAST)
2005 				continue;
2006 
2007 			if (((struct in6_ifaddr *)ifa)->ia6_flags &
2008 			    IN6_IFF_DETACHED)
2009 				continue;
2010 
2011 			/*
2012 			 * If this is the first address we find,
2013 			 * keep it anyway.
2014 			 */
2015 			if (ifa_best == NULL)
2016 				goto replace;
2017 
2018 			/*
2019 			 * ifa_best is never NULL beyond this line except
2020 			 * within the block labeled "replace".
2021 			 */
2022 
2023 			/*
2024 			 * If ifa_best has a smaller scope than dst and
2025 			 * the current address has a larger one than
2026 			 * (or equal to) dst, always replace ifa_best.
2027 			 * Also, if the current address has a smaller scope
2028 			 * than dst, ignore it unless ifa_best also has a
2029 			 * smaller scope.
2030 			 * Consequently, after the two if-clause below,
2031 			 * the followings must be satisfied:
2032 			 * (scope(src) < scope(dst) &&
2033 			 *  scope(best) < scope(dst))
2034 			 *  OR
2035 			 * (scope(best) >= scope(dst) &&
2036 			 *  scope(src) >= scope(dst))
2037 			 */
2038 			if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0 &&
2039 			    IN6_ARE_SCOPE_CMP(src_scope, dst_scope) >= 0)
2040 				goto replace; /* (A) */
2041 			if (IN6_ARE_SCOPE_CMP(src_scope, dst_scope) < 0 &&
2042 			    IN6_ARE_SCOPE_CMP(best_scope, dst_scope) >= 0)
2043 				continue; /* (B) */
2044 
2045 			/*
2046 			 * A deprecated address SHOULD NOT be used in new
2047 			 * communications if an alternate (non-deprecated)
2048 			 * address is available and has sufficient scope.
2049 			 * RFC 2462, Section 5.5.4.
2050 			 */
2051 			if (((struct in6_ifaddr *)ifa)->ia6_flags &
2052 			    IN6_IFF_DEPRECATED) {
2053 				/*
2054 				 * Ignore any deprecated addresses if
2055 				 * specified by configuration.
2056 				 */
2057 				if (!ip6_use_deprecated)
2058 					continue;
2059 
2060 				/*
2061 				 * If we have already found a non-deprecated
2062 				 * candidate, just ignore deprecated addresses.
2063 				 */
2064 				if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED)
2065 				    == 0)
2066 					continue;
2067 			}
2068 
2069 			/*
2070 			 * A non-deprecated address is always preferred
2071 			 * to a deprecated one regardless of scopes and
2072 			 * address matching (Note invariants ensured by the
2073 			 * conditions (A) and (B) above.)
2074 			 */
2075 			if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED) &&
2076 			    (((struct in6_ifaddr *)ifa)->ia6_flags &
2077 			     IN6_IFF_DEPRECATED) == 0)
2078 				goto replace;
2079 
2080 			/*
2081 			 * When we use temporary addresses described in
2082 			 * RFC 3041, we prefer temporary addresses to
2083 			 * public autoconf addresses.  Again, note the
2084 			 * invariants from (A) and (B).  Also note that we
2085 			 * don't have any preference between static addresses
2086 			 * and autoconf addresses (despite of whether or not
2087 			 * the latter is temporary or public.)
2088 			 */
2089 			if (ip6_use_tempaddr) {
2090 				struct in6_ifaddr *ifat;
2091 
2092 				ifat = (struct in6_ifaddr *)ifa;
2093 				if ((ifa_best->ia6_flags &
2094 				     (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY))
2095 				     == IN6_IFF_AUTOCONF &&
2096 				    (ifat->ia6_flags &
2097 				     (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY))
2098 				     == (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY)) {
2099 					goto replace;
2100 				}
2101 				if ((ifa_best->ia6_flags &
2102 				     (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY))
2103 				    == (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY) &&
2104 				    (ifat->ia6_flags &
2105 				     (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY))
2106 				     == IN6_IFF_AUTOCONF) {
2107 					continue;
2108 				}
2109 			}
2110 
2111 			/*
2112 			 * At this point, we have two cases:
2113 			 * 1. we are looking at a non-deprecated address,
2114 			 *    and ifa_best is also non-deprecated.
2115 			 * 2. we are looking at a deprecated address,
2116 			 *    and ifa_best is also deprecated.
2117 			 * Also, we do not have to consider a case where
2118 			 * the scope of if_best is larger(smaller) than dst and
2119 			 * the scope of the current address is smaller(larger)
2120 			 * than dst. Such a case has already been covered.
2121 			 * Tiebreaking is done according to the following
2122 			 * items:
2123 			 * - the scope comparison between the address and
2124 			 *   dst (dscopecmp)
2125 			 * - the scope comparison between the address and
2126 			 *   ifa_best (bscopecmp)
2127 			 * - if the address match dst longer than ifa_best
2128 			 *   (matchcmp)
2129 			 * - if the address is on the outgoing I/F (outI/F)
2130 			 *
2131 			 * Roughly speaking, the selection policy is
2132 			 * - the most important item is scope. The same scope
2133 			 *   is best. Then search for a larger scope.
2134 			 *   Smaller scopes are the last resort.
2135 			 * - A deprecated address is chosen only when we have
2136 			 *   no address that has an enough scope, but is
2137 			 *   prefered to any addresses of smaller scopes
2138 			 *   (this must be already done above.)
2139 			 * - addresses on the outgoing I/F are preferred to
2140 			 *   ones on other interfaces if none of above
2141 			 *   tiebreaks.  In the table below, the column "bI"
2142 			 *   means if the best_ifa is on the outgoing
2143 			 *   interface, and the column "sI" means if the ifa
2144 			 *   is on the outgoing interface.
2145 			 * - If there is no other reasons to choose one,
2146 			 *   longest address match against dst is considered.
2147 			 *
2148 			 * The precise decision table is as follows:
2149 			 * dscopecmp bscopecmp    match  bI oI | replace?
2150 			 *       N/A     equal      N/A   Y  N |   No (1)
2151 			 *       N/A     equal      N/A   N  Y |  Yes (2)
2152 			 *       N/A     equal   larger    N/A |  Yes (3)
2153 			 *       N/A     equal  !larger    N/A |   No (4)
2154 			 *    larger    larger      N/A    N/A |   No (5)
2155 			 *    larger   smaller      N/A    N/A |  Yes (6)
2156 			 *   smaller    larger      N/A    N/A |  Yes (7)
2157 			 *   smaller   smaller      N/A    N/A |   No (8)
2158 			 *     equal   smaller      N/A    N/A |  Yes (9)
2159 			 *     equal    larger       (already done at A above)
2160 			 */
2161 			dscopecmp = IN6_ARE_SCOPE_CMP(src_scope, dst_scope);
2162 			bscopecmp = IN6_ARE_SCOPE_CMP(src_scope, best_scope);
2163 
2164 			if (bscopecmp == 0) {
2165 				struct ifnet *bifp = ifa_best->ia_ifp;
2166 
2167 				if (bifp == oifp && ifp != oifp) /* (1) */
2168 					continue;
2169 				if (bifp != oifp && ifp == oifp) /* (2) */
2170 					goto replace;
2171 
2172 				/*
2173 				 * Both bifp and ifp are on the outgoing
2174 				 * interface, or both two are on a different
2175 				 * interface from the outgoing I/F.
2176 				 * now we need address matching against dst
2177 				 * for tiebreaking.
2178 				 */
2179 				tlen = in6_matchlen(IFA_IN6(ifa), dst);
2180 				matchcmp = tlen - blen;
2181 				if (matchcmp > 0) /* (3) */
2182 					goto replace;
2183 				continue; /* (4) */
2184 			}
2185 			if (dscopecmp > 0) {
2186 				if (bscopecmp > 0) /* (5) */
2187 					continue;
2188 				goto replace; /* (6) */
2189 			}
2190 			if (dscopecmp < 0) {
2191 				if (bscopecmp > 0) /* (7) */
2192 					goto replace;
2193 				continue; /* (8) */
2194 			}
2195 
2196 			/* now dscopecmp must be 0 */
2197 			if (bscopecmp < 0)
2198 				goto replace; /* (9) */
2199 
2200 		  replace:
2201 			ifa_best = (struct in6_ifaddr *)ifa;
2202 			blen = tlen >= 0 ? tlen :
2203 				in6_matchlen(IFA_IN6(ifa), dst);
2204 			best_scope = in6_addrscope(&ifa_best->ia_addr.sin6_addr);
2205 		}
2206 	}
2207 
2208 	/* count statistics for future improvements */
2209 	if (ifa_best == NULL)
2210 		ip6stat.ip6s_sources_none++;
2211 	else {
2212 		if (oifp == ifa_best->ia_ifp)
2213 			ip6stat.ip6s_sources_sameif[best_scope]++;
2214 		else
2215 			ip6stat.ip6s_sources_otherif[best_scope]++;
2216 
2217 		if (best_scope == dst_scope)
2218 			ip6stat.ip6s_sources_samescope[best_scope]++;
2219 		else
2220 			ip6stat.ip6s_sources_otherscope[best_scope]++;
2221 
2222 		if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED) != 0)
2223 			ip6stat.ip6s_sources_deprecated[best_scope]++;
2224 	}
2225 
2226 	return(ifa_best);
2227 }
2228 
2229 /*
2230  * return the best address out of the same scope. if no address was
2231  * found, return the first valid address from designated IF.
2232  */
2233 struct in6_ifaddr *
2234 in6_ifawithifp(ifp, dst)
2235 	struct ifnet *ifp;
2236 	struct in6_addr *dst;
2237 {
2238 	int dst_scope =	in6_addrscope(dst), blen = -1, tlen;
2239 	struct ifaddr *ifa;
2240 	struct in6_ifaddr *besta = 0;
2241 	struct in6_ifaddr *dep[2];	/* last-resort: deprecated */
2242 
2243 	dep[0] = dep[1] = NULL;
2244 
2245 	/*
2246 	 * We first look for addresses in the same scope.
2247 	 * If there is one, return it.
2248 	 * If two or more, return one which matches the dst longest.
2249 	 * If none, return one of global addresses assigned other ifs.
2250 	 */
2251 	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
2252 	{
2253 		if (ifa->ifa_addr->sa_family != AF_INET6)
2254 			continue;
2255 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)
2256 			continue; /* XXX: is there any case to allow anycast? */
2257 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY)
2258 			continue; /* don't use this interface */
2259 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DETACHED)
2260 			continue;
2261 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
2262 			if (ip6_use_deprecated)
2263 				dep[0] = (struct in6_ifaddr *)ifa;
2264 			continue;
2265 		}
2266 
2267 		if (dst_scope == in6_addrscope(IFA_IN6(ifa))) {
2268 			/*
2269 			 * call in6_matchlen() as few as possible
2270 			 */
2271 			if (besta) {
2272 				if (blen == -1)
2273 					blen = in6_matchlen(&besta->ia_addr.sin6_addr, dst);
2274 				tlen = in6_matchlen(IFA_IN6(ifa), dst);
2275 				if (tlen > blen) {
2276 					blen = tlen;
2277 					besta = (struct in6_ifaddr *)ifa;
2278 				}
2279 			} else
2280 				besta = (struct in6_ifaddr *)ifa;
2281 		}
2282 	}
2283 	if (besta)
2284 		return(besta);
2285 
2286 	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
2287 	{
2288 		if (ifa->ifa_addr->sa_family != AF_INET6)
2289 			continue;
2290 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)
2291 			continue; /* XXX: is there any case to allow anycast? */
2292 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY)
2293 			continue; /* don't use this interface */
2294 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DETACHED)
2295 			continue;
2296 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
2297 			if (ip6_use_deprecated)
2298 				dep[1] = (struct in6_ifaddr *)ifa;
2299 			continue;
2300 		}
2301 
2302 		return (struct in6_ifaddr *)ifa;
2303 	}
2304 
2305 	/* use the last-resort values, that are, deprecated addresses */
2306 	if (dep[0])
2307 		return dep[0];
2308 	if (dep[1])
2309 		return dep[1];
2310 
2311 	return NULL;
2312 }
2313 
2314 /*
2315  * perform DAD when interface becomes IFF_UP.
2316  */
2317 void
2318 in6_if_up(ifp)
2319 	struct ifnet *ifp;
2320 {
2321 	struct ifaddr *ifa;
2322 	struct in6_ifaddr *ia;
2323 	int dad_delay;		/* delay ticks before DAD output */
2324 
2325 	/*
2326 	 * special cases, like 6to4, are handled in in6_ifattach
2327 	 */
2328 	in6_ifattach(ifp, NULL);
2329 
2330 	dad_delay = 0;
2331 	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
2332 	{
2333 		if (ifa->ifa_addr->sa_family != AF_INET6)
2334 			continue;
2335 		ia = (struct in6_ifaddr *)ifa;
2336 		if (ia->ia6_flags & IN6_IFF_TENTATIVE)
2337 			nd6_dad_start(ifa, &dad_delay);
2338 	}
2339 }
2340 
2341 int
2342 in6if_do_dad(ifp)
2343 	struct ifnet *ifp;
2344 {
2345 	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2346 		return(0);
2347 
2348 	switch (ifp->if_type) {
2349 #ifdef IFT_DUMMY
2350 	case IFT_DUMMY:
2351 #endif
2352 	case IFT_FAITH:
2353 		/*
2354 		 * These interfaces do not have the IFF_LOOPBACK flag,
2355 		 * but loop packets back.  We do not have to do DAD on such
2356 		 * interfaces.  We should even omit it, because loop-backed
2357 		 * NS would confuse the DAD procedure.
2358 		 */
2359 		return(0);
2360 	default:
2361 		/*
2362 		 * Our DAD routine requires the interface up and running.
2363 		 * However, some interfaces can be up before the RUNNING
2364 		 * status.  Additionaly, users may try to assign addresses
2365 		 * before the interface becomes up (or running).
2366 		 * We simply skip DAD in such a case as a work around.
2367 		 * XXX: we should rather mark "tentative" on such addresses,
2368 		 * and do DAD after the interface becomes ready.
2369 		 */
2370 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
2371 		    (IFF_UP|IFF_RUNNING))
2372 			return(0);
2373 
2374 		return(1);
2375 	}
2376 }
2377 
2378 /*
2379  * Calculate max IPv6 MTU through all the interfaces and store it
2380  * to in6_maxmtu.
2381  */
2382 void
2383 in6_setmaxmtu()
2384 {
2385 	unsigned long maxmtu = 0;
2386 	struct ifnet *ifp;
2387 
2388 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
2389 	{
2390 		if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
2391 		    nd_ifinfo[ifp->if_index].linkmtu > maxmtu)
2392 			maxmtu =  nd_ifinfo[ifp->if_index].linkmtu;
2393 	}
2394 	if (maxmtu)	/* update only when maxmtu is positive */
2395 		in6_maxmtu = maxmtu;
2396 }
2397 
2398 /*
2399  * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
2400  * v4 mapped addr or v4 compat addr
2401  */
2402 void
2403 in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2404 {
2405 	bzero(sin, sizeof(*sin));
2406 	sin->sin_len = sizeof(struct sockaddr_in);
2407 	sin->sin_family = AF_INET;
2408 	sin->sin_port = sin6->sin6_port;
2409 	sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];
2410 }
2411 
2412 /* Convert sockaddr_in to sockaddr_in6 in v4 mapped addr format. */
2413 void
2414 in6_sin_2_v4mapsin6(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
2415 {
2416 	bzero(sin6, sizeof(*sin6));
2417 	sin6->sin6_len = sizeof(struct sockaddr_in6);
2418 	sin6->sin6_family = AF_INET6;
2419 	sin6->sin6_port = sin->sin_port;
2420 	sin6->sin6_addr.s6_addr32[0] = 0;
2421 	sin6->sin6_addr.s6_addr32[1] = 0;
2422 	sin6->sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
2423 	sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;
2424 }
2425 
2426 /* Convert sockaddr_in6 into sockaddr_in. */
2427 void
2428 in6_sin6_2_sin_in_sock(struct sockaddr *nam)
2429 {
2430 	struct sockaddr_in *sin_p;
2431 	struct sockaddr_in6 sin6;
2432 
2433 	/*
2434 	 * Save original sockaddr_in6 addr and convert it
2435 	 * to sockaddr_in.
2436 	 */
2437 	sin6 = *(struct sockaddr_in6 *)nam;
2438 	sin_p = (struct sockaddr_in *)nam;
2439 	in6_sin6_2_sin(sin_p, &sin6);
2440 }
2441 
2442 /* Convert sockaddr_in into sockaddr_in6 in v4 mapped addr format. */
2443 void
2444 in6_sin_2_v4mapsin6_in_sock(struct sockaddr **nam)
2445 {
2446 	struct sockaddr_in *sin_p;
2447 	struct sockaddr_in6 *sin6_p;
2448 
2449 	MALLOC(sin6_p, struct sockaddr_in6 *, sizeof *sin6_p, M_SONAME,
2450 	       M_WAITOK);
2451 	sin_p = (struct sockaddr_in *)*nam;
2452 	in6_sin_2_v4mapsin6(sin_p, sin6_p);
2453 	FREE(*nam, M_SONAME);
2454 	*nam = (struct sockaddr *)sin6_p;
2455 }
2456