xref: /netbsd-src/sys/netinet6/in6.c (revision 27527e67bbdf8d9ec84fd58803048ed6d181ece2)
1 /*	$NetBSD: in6.c,v 1.95 2006/01/21 00:15:36 rpaulo 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 1.95 2006/01/21 00:15:36 rpaulo Exp $");
66 
67 #include "opt_inet.h"
68 #include "opt_pfil_hooks.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 
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 <net/if_ether.h>
91 
92 #include <netinet/ip6.h>
93 #include <netinet6/ip6_var.h>
94 #include <netinet6/nd6.h>
95 #include <netinet6/mld6_var.h>
96 #include <netinet6/ip6_mroute.h>
97 #include <netinet6/in6_ifattach.h>
98 #include <netinet6/scope6_var.h>
99 
100 #include <net/net_osdep.h>
101 
102 #ifdef PFIL_HOOKS
103 #include <net/pfil.h>
104 #endif
105 
106 MALLOC_DEFINE(M_IP6OPT, "ip6_options", "IPv6 options");
107 
108 /* enable backward compatibility code for obsoleted ioctls */
109 #define COMPAT_IN6IFIOCTL
110 
111 /*
112  * Definitions of some constant IP6 addresses.
113  */
114 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
115 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
116 const struct in6_addr in6addr_nodelocal_allnodes =
117 	IN6ADDR_NODELOCAL_ALLNODES_INIT;
118 const struct in6_addr in6addr_linklocal_allnodes =
119 	IN6ADDR_LINKLOCAL_ALLNODES_INIT;
120 const struct in6_addr in6addr_linklocal_allrouters =
121 	IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
122 
123 const struct in6_addr in6mask0 = IN6MASK0;
124 const struct in6_addr in6mask32 = IN6MASK32;
125 const struct in6_addr in6mask64 = IN6MASK64;
126 const struct in6_addr in6mask96 = IN6MASK96;
127 const struct in6_addr in6mask128 = IN6MASK128;
128 
129 const struct sockaddr_in6 sa6_any = {sizeof(sa6_any), AF_INET6,
130 				     0, 0, IN6ADDR_ANY_INIT, 0};
131 
132 static int in6_lifaddr_ioctl __P((struct socket *, u_long, caddr_t,
133 	struct ifnet *, struct proc *));
134 static int in6_ifinit __P((struct ifnet *, struct in6_ifaddr *,
135 	struct sockaddr_in6 *, int));
136 static void in6_unlink_ifa __P((struct in6_ifaddr *, struct ifnet *));
137 
138 /*
139  * This structure is used to keep track of in6_multi chains which belong to
140  * deleted interface addresses.
141  */
142 static LIST_HEAD(, multi6_kludge) in6_mk; /* XXX BSS initialization */
143 
144 struct multi6_kludge {
145 	LIST_ENTRY(multi6_kludge) mk_entry;
146 	struct ifnet *mk_ifp;
147 	struct in6_multihead mk_head;
148 };
149 
150 /*
151  * Subroutine for in6_ifaddloop() and in6_ifremloop().
152  * This routine does actual work.
153  */
154 static void
155 in6_ifloop_request(int cmd, struct ifaddr *ifa)
156 {
157 	struct sockaddr_in6 lo_sa;
158 	struct sockaddr_in6 all1_sa;
159 	struct rtentry *nrt = NULL;
160 	int e;
161 
162 	bzero(&lo_sa, sizeof(lo_sa));
163 	bzero(&all1_sa, sizeof(all1_sa));
164 	lo_sa.sin6_family = all1_sa.sin6_family = AF_INET6;
165 	lo_sa.sin6_len = all1_sa.sin6_len = sizeof(struct sockaddr_in6);
166 	lo_sa.sin6_addr = in6addr_loopback;
167 	all1_sa.sin6_addr = in6mask128;
168 
169 	/*
170 	 * We specify the address itself as the gateway, and set the
171 	 * RTF_LLINFO flag, so that the corresponding host route would have
172 	 * the flag, and thus applications that assume traditional behavior
173 	 * would be happy.  Note that we assume the caller of the function
174 	 * (probably implicitly) set nd6_rtrequest() to ifa->ifa_rtrequest,
175 	 * which changes the outgoing interface to the loopback interface.
176 	 */
177 	e = rtrequest(cmd, ifa->ifa_addr, ifa->ifa_addr,
178 	    (struct sockaddr *)&all1_sa, RTF_UP|RTF_HOST|RTF_LLINFO, &nrt);
179 	if (e != 0) {
180 		log(LOG_ERR, "in6_ifloop_request: "
181 		    "%s operation failed for %s (errno=%d)\n",
182 		    cmd == RTM_ADD ? "ADD" : "DELETE",
183 		    ip6_sprintf(&((struct in6_ifaddr *)ifa)->ia_addr.sin6_addr),
184 		    e);
185 	}
186 
187 	/*
188 	 * Make sure rt_ifa be equal to IFA, the second argument of the
189 	 * function.
190 	 * We need this because when we refer to rt_ifa->ia6_flags in
191 	 * ip6_input, we assume that the rt_ifa points to the address instead
192 	 * of the loopback address.
193 	 */
194 	if (cmd == RTM_ADD && nrt && ifa != nrt->rt_ifa) {
195 		IFAFREE(nrt->rt_ifa);
196 		IFAREF(ifa);
197 		nrt->rt_ifa = ifa;
198 	}
199 
200 	/*
201 	 * Report the addition/removal of the address to the routing socket.
202 	 * XXX: since we called rtinit for a p2p interface with a destination,
203 	 *      we end up reporting twice in such a case.  Should we rather
204 	 *      omit the second report?
205 	 */
206 	if (nrt) {
207 		rt_newaddrmsg(cmd, ifa, e, nrt);
208 		if (cmd == RTM_DELETE) {
209 			if (nrt->rt_refcnt <= 0) {
210 				/* XXX: we should free the entry ourselves. */
211 				nrt->rt_refcnt++;
212 				rtfree(nrt);
213 			}
214 		} else {
215 			/* the cmd must be RTM_ADD here */
216 			nrt->rt_refcnt--;
217 		}
218 	}
219 }
220 
221 /*
222  * Add ownaddr as loopback rtentry.  We previously add the route only if
223  * necessary (ex. on a p2p link).  However, since we now manage addresses
224  * separately from prefixes, we should always add the route.  We can't
225  * rely on the cloning mechanism from the corresponding interface route
226  * any more.
227  */
228 static void
229 in6_ifaddloop(struct ifaddr *ifa)
230 {
231 	struct rtentry *rt;
232 
233 	/* If there is no loopback entry, allocate one. */
234 	rt = rtalloc1(ifa->ifa_addr, 0);
235 	if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0 ||
236 	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
237 		in6_ifloop_request(RTM_ADD, ifa);
238 	if (rt)
239 		rt->rt_refcnt--;
240 }
241 
242 /*
243  * Remove loopback rtentry of ownaddr generated by in6_ifaddloop(),
244  * if it exists.
245  */
246 static void
247 in6_ifremloop(struct ifaddr *ifa)
248 {
249 	struct in6_ifaddr *ia;
250 	struct rtentry *rt;
251 	int ia_count = 0;
252 
253 	/*
254 	 * Some of BSD variants do not remove cloned routes
255 	 * from an interface direct route, when removing the direct route
256 	 * (see comments in net/net_osdep.h).  Even for variants that do remove
257 	 * cloned routes, they could fail to remove the cloned routes when
258 	 * we handle multple addresses that share a common prefix.
259 	 * So, we should remove the route corresponding to the deleted address.
260 	 */
261 
262 	/*
263 	 * Delete the entry only if exact one ifa exists.  More than one ifa
264 	 * can exist if we assign a same single address to multiple
265 	 * (probably p2p) interfaces.
266 	 * XXX: we should avoid such a configuration in IPv6...
267 	 */
268 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
269 		if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ia->ia_addr.sin6_addr)) {
270 			ia_count++;
271 			if (ia_count > 1)
272 				break;
273 		}
274 	}
275 
276 	if (ia_count == 1) {
277 		/*
278 		 * Before deleting, check if a corresponding loopbacked host
279 		 * route surely exists.  With this check, we can avoid to
280 		 * delete an interface direct route whose destination is same
281 		 * as the address being removed.  This can happen when removing
282 		 * a subnet-router anycast address on an interface attahced
283 		 * to a shared medium.
284 		 */
285 		rt = rtalloc1(ifa->ifa_addr, 0);
286 		if (rt != NULL && (rt->rt_flags & RTF_HOST) != 0 &&
287 		    (rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
288 			rt->rt_refcnt--;
289 			in6_ifloop_request(RTM_DELETE, ifa);
290 		}
291 	}
292 }
293 
294 int
295 in6_mask2len(mask, lim0)
296 	struct in6_addr *mask;
297 	u_char *lim0;
298 {
299 	int x = 0, y;
300 	u_char *lim = lim0, *p;
301 
302 	/* ignore the scope_id part */
303 	if (lim0 == NULL || lim0 - (u_char *)mask > sizeof(*mask))
304 		lim = (u_char *)mask + sizeof(*mask);
305 	for (p = (u_char *)mask; p < lim; x++, p++) {
306 		if (*p != 0xff)
307 			break;
308 	}
309 	y = 0;
310 	if (p < lim) {
311 		for (y = 0; y < 8; y++) {
312 			if ((*p & (0x80 >> y)) == 0)
313 				break;
314 		}
315 	}
316 
317 	/*
318 	 * when the limit pointer is given, do a stricter check on the
319 	 * remaining bits.
320 	 */
321 	if (p < lim) {
322 		if (y != 0 && (*p & (0x00ff >> y)) != 0)
323 			return (-1);
324 		for (p = p + 1; p < lim; p++)
325 			if (*p != 0)
326 				return (-1);
327 	}
328 
329 	return x * 8 + y;
330 }
331 
332 #define ifa2ia6(ifa)	((struct in6_ifaddr *)(ifa))
333 #define ia62ifa(ia6)	(&((ia6)->ia_ifa))
334 
335 int
336 in6_control(so, cmd, data, ifp, p)
337 	struct	socket *so;
338 	u_long cmd;
339 	caddr_t	data;
340 	struct ifnet *ifp;
341 	struct proc *p;
342 {
343 	struct	in6_ifreq *ifr = (struct in6_ifreq *)data;
344 	struct	in6_ifaddr *ia = NULL;
345 	struct	in6_aliasreq *ifra = (struct in6_aliasreq *)data;
346 	struct sockaddr_in6 *sa6;
347 	int error, privileged;
348 
349 	privileged = 0;
350 	if (p && !suser(p->p_ucred, &p->p_acflag))
351 		privileged++;
352 
353 	switch (cmd) {
354 	case SIOCGETSGCNT_IN6:
355 	case SIOCGETMIFCNT_IN6:
356 		return (mrt6_ioctl(cmd, data));
357 	}
358 
359 	if (ifp == NULL)
360 		return (EOPNOTSUPP);
361 
362 	switch (cmd) {
363 	case SIOCSNDFLUSH_IN6:
364 	case SIOCSPFXFLUSH_IN6:
365 	case SIOCSRTRFLUSH_IN6:
366 	case SIOCSDEFIFACE_IN6:
367 	case SIOCSIFINFO_FLAGS:
368 		if (!privileged)
369 			return (EPERM);
370 		/* FALLTHROUGH */
371 	case OSIOCGIFINFO_IN6:
372 	case SIOCGIFINFO_IN6:
373 	case SIOCGDRLST_IN6:
374 	case SIOCGPRLST_IN6:
375 	case SIOCGNBRINFO_IN6:
376 	case SIOCGDEFIFACE_IN6:
377 		return (nd6_ioctl(cmd, data, ifp));
378 	}
379 
380 	switch (cmd) {
381 	case SIOCSIFPREFIX_IN6:
382 	case SIOCDIFPREFIX_IN6:
383 	case SIOCAIFPREFIX_IN6:
384 	case SIOCCIFPREFIX_IN6:
385 	case SIOCSGIFPREFIX_IN6:
386 	case SIOCGIFPREFIX_IN6:
387 		log(LOG_NOTICE,
388 		    "prefix ioctls are now invalidated. "
389 		    "please use ifconfig.\n");
390 		return (EOPNOTSUPP);
391 	}
392 
393 	switch (cmd) {
394 	case SIOCALIFADDR:
395 	case SIOCDLIFADDR:
396 		if (!privileged)
397 			return (EPERM);
398 		/* FALLTHROUGH */
399 	case SIOCGLIFADDR:
400 		return in6_lifaddr_ioctl(so, cmd, data, ifp, p);
401 	}
402 
403 	/*
404 	 * Find address for this interface, if it exists.
405 	 *
406 	 * In netinet code, we have checked ifra_addr in SIOCSIF*ADDR operation
407 	 * only, and used the first interface address as the target of other
408 	 * operations (without checking ifra_addr).  This was because netinet
409 	 * code/API assumed at most 1 interface address per interface.
410 	 * Since IPv6 allows a node to assign multiple addresses
411 	 * on a single interface, we almost always look and check the
412 	 * presence of ifra_addr, and reject invalid ones here.
413 	 * It also decreases duplicated code among SIOC*_IN6 operations.
414 	 */
415 	switch (cmd) {
416 	case SIOCAIFADDR_IN6:
417 	case SIOCSIFPHYADDR_IN6:
418 		sa6 = &ifra->ifra_addr;
419 		break;
420 	case SIOCSIFADDR_IN6:
421 	case SIOCGIFADDR_IN6:
422 	case SIOCSIFDSTADDR_IN6:
423 	case SIOCSIFNETMASK_IN6:
424 	case SIOCGIFDSTADDR_IN6:
425 	case SIOCGIFNETMASK_IN6:
426 	case SIOCDIFADDR_IN6:
427 	case SIOCGIFPSRCADDR_IN6:
428 	case SIOCGIFPDSTADDR_IN6:
429 	case SIOCGIFAFLAG_IN6:
430 	case SIOCSNDFLUSH_IN6:
431 	case SIOCSPFXFLUSH_IN6:
432 	case SIOCSRTRFLUSH_IN6:
433 	case SIOCGIFALIFETIME_IN6:
434 	case SIOCSIFALIFETIME_IN6:
435 	case SIOCGIFSTAT_IN6:
436 	case SIOCGIFSTAT_ICMP6:
437 		sa6 = &ifr->ifr_addr;
438 		break;
439 	default:
440 		sa6 = NULL;
441 		break;
442 	}
443 	if (sa6 && sa6->sin6_family == AF_INET6) {
444 		if (sa6->sin6_scope_id != 0)
445 			error = sa6_embedscope(sa6, 0);
446 		else
447 			error = in6_setscope(&sa6->sin6_addr, ifp, NULL);
448 		if (error != 0)
449 			return (error);
450 		ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
451 	} else
452 		ia = NULL;
453 
454 	switch (cmd) {
455 	case SIOCSIFADDR_IN6:
456 	case SIOCSIFDSTADDR_IN6:
457 	case SIOCSIFNETMASK_IN6:
458 		/*
459 		 * Since IPv6 allows a node to assign multiple addresses
460 		 * on a single interface, SIOCSIFxxx ioctls are deprecated.
461 		 */
462 		return (EINVAL);
463 
464 	case SIOCDIFADDR_IN6:
465 		/*
466 		 * for IPv4, we look for existing in_ifaddr here to allow
467 		 * "ifconfig if0 delete" to remove the first IPv4 address on
468 		 * the interface.  For IPv6, as the spec allows multiple
469 		 * interface address from the day one, we consider "remove the
470 		 * first one" semantics to be not preferable.
471 		 */
472 		if (ia == NULL)
473 			return (EADDRNOTAVAIL);
474 		/* FALLTHROUGH */
475 	case SIOCAIFADDR_IN6:
476 		/*
477 		 * We always require users to specify a valid IPv6 address for
478 		 * the corresponding operation.
479 		 */
480 		if (ifra->ifra_addr.sin6_family != AF_INET6 ||
481 		    ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6))
482 			return (EAFNOSUPPORT);
483 		if (!privileged)
484 			return (EPERM);
485 
486 		break;
487 
488 	case SIOCGIFADDR_IN6:
489 		/* This interface is basically deprecated. use SIOCGIFCONF. */
490 		/* FALLTHROUGH */
491 	case SIOCGIFAFLAG_IN6:
492 	case SIOCGIFNETMASK_IN6:
493 	case SIOCGIFDSTADDR_IN6:
494 	case SIOCGIFALIFETIME_IN6:
495 		/* must think again about its semantics */
496 		if (ia == NULL)
497 			return (EADDRNOTAVAIL);
498 		break;
499 	case SIOCSIFALIFETIME_IN6:
500 	    {
501 		struct in6_addrlifetime *lt;
502 
503 		if (!privileged)
504 			return (EPERM);
505 		if (ia == NULL)
506 			return (EADDRNOTAVAIL);
507 		/* sanity for overflow - beware unsigned */
508 		lt = &ifr->ifr_ifru.ifru_lifetime;
509 		if (lt->ia6t_vltime != ND6_INFINITE_LIFETIME
510 		 && lt->ia6t_vltime + time.tv_sec < time.tv_sec) {
511 			return EINVAL;
512 		}
513 		if (lt->ia6t_pltime != ND6_INFINITE_LIFETIME
514 		 && lt->ia6t_pltime + time.tv_sec < time.tv_sec) {
515 			return EINVAL;
516 		}
517 		break;
518 	    }
519 	}
520 
521 	switch (cmd) {
522 
523 	case SIOCGIFADDR_IN6:
524 		ifr->ifr_addr = ia->ia_addr;
525 		if ((error = sa6_recoverscope(&ifr->ifr_addr)) != 0)
526 			return (error);
527 		break;
528 
529 	case SIOCGIFDSTADDR_IN6:
530 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
531 			return (EINVAL);
532 		/*
533 		 * XXX: should we check if ifa_dstaddr is NULL and return
534 		 * an error?
535 		 */
536 		ifr->ifr_dstaddr = ia->ia_dstaddr;
537 		if ((error = sa6_recoverscope(&ifr->ifr_dstaddr)) != 0)
538 			return (error);
539 		break;
540 
541 	case SIOCGIFNETMASK_IN6:
542 		ifr->ifr_addr = ia->ia_prefixmask;
543 		break;
544 
545 	case SIOCGIFAFLAG_IN6:
546 		ifr->ifr_ifru.ifru_flags6 = ia->ia6_flags;
547 		break;
548 
549 	case SIOCGIFSTAT_IN6:
550 		if (ifp == NULL)
551 			return EINVAL;
552 		bzero(&ifr->ifr_ifru.ifru_stat,
553 		    sizeof(ifr->ifr_ifru.ifru_stat));
554 		ifr->ifr_ifru.ifru_stat =
555 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->in6_ifstat;
556 		break;
557 
558 	case SIOCGIFSTAT_ICMP6:
559 		if (ifp == NULL)
560 			return EINVAL;
561 		bzero(&ifr->ifr_ifru.ifru_stat,
562 		    sizeof(ifr->ifr_ifru.ifru_icmp6stat));
563 		ifr->ifr_ifru.ifru_icmp6stat =
564 		    *((struct in6_ifextra *)ifp->if_afdata[AF_INET6])->icmp6_ifstat;
565 		break;
566 
567 	case SIOCGIFALIFETIME_IN6:
568 		ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
569 		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
570 			time_t maxexpire;
571 			struct in6_addrlifetime *retlt =
572 			    &ifr->ifr_ifru.ifru_lifetime;
573 
574 			/*
575 			 * XXX: adjust expiration time assuming time_t is
576 			 * signed.
577 			 */
578 			maxexpire = (-1) &
579 			    ~(1 << ((sizeof(maxexpire) * 8) - 1));
580 			if (ia->ia6_lifetime.ia6t_vltime <
581 			    maxexpire - ia->ia6_updatetime) {
582 				retlt->ia6t_expire = ia->ia6_updatetime +
583 				    ia->ia6_lifetime.ia6t_vltime;
584 			} else
585 				retlt->ia6t_expire = maxexpire;
586 		}
587 		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
588 			time_t maxexpire;
589 			struct in6_addrlifetime *retlt =
590 			    &ifr->ifr_ifru.ifru_lifetime;
591 
592 			/*
593 			 * XXX: adjust expiration time assuming time_t is
594 			 * signed.
595 			 */
596 			maxexpire = (-1) &
597 			    ~(1 << ((sizeof(maxexpire) * 8) - 1));
598 			if (ia->ia6_lifetime.ia6t_pltime <
599 			    maxexpire - ia->ia6_updatetime) {
600 				retlt->ia6t_preferred = ia->ia6_updatetime +
601 				    ia->ia6_lifetime.ia6t_pltime;
602 			} else
603 				retlt->ia6t_preferred = maxexpire;
604 		}
605 		break;
606 
607 	case SIOCSIFALIFETIME_IN6:
608 		ia->ia6_lifetime = ifr->ifr_ifru.ifru_lifetime;
609 		/* for sanity */
610 		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
611 			ia->ia6_lifetime.ia6t_expire =
612 				time.tv_sec + ia->ia6_lifetime.ia6t_vltime;
613 		} else
614 			ia->ia6_lifetime.ia6t_expire = 0;
615 		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
616 			ia->ia6_lifetime.ia6t_preferred =
617 				time.tv_sec + ia->ia6_lifetime.ia6t_pltime;
618 		} else
619 			ia->ia6_lifetime.ia6t_preferred = 0;
620 		break;
621 
622 	case SIOCAIFADDR_IN6:
623 	{
624 		int i;
625 		struct nd_prefix pr0, *pr;
626 
627 		/* reject read-only flags */
628 		if ((ifra->ifra_flags & IN6_IFF_DUPLICATED) != 0 ||
629 		    (ifra->ifra_flags & IN6_IFF_DETACHED) != 0 ||
630 		    (ifra->ifra_flags & IN6_IFF_NODAD) != 0 ||
631 		    (ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0) {
632 			return (EINVAL);
633 		}
634 		/*
635 		 * first, make or update the interface address structure,
636 		 * and link it to the list.
637 		 */
638 		if ((error = in6_update_ifa(ifp, ifra, ia)) != 0)
639 			return (error);
640 		if ((ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr))
641 		    == NULL) {
642 		    	/*
643 			 * this can happen when the user specify the 0 valid
644 			 * lifetime.
645 			 */
646 			break;
647 		}
648 
649 		/*
650 		 * then, make the prefix on-link on the interface.
651 		 * XXX: we'd rather create the prefix before the address, but
652 		 * we need at least one address to install the corresponding
653 		 * interface route, so we configure the address first.
654 		 */
655 
656 		/*
657 		 * convert mask to prefix length (prefixmask has already
658 		 * been validated in in6_update_ifa().
659 		 */
660 		bzero(&pr0, sizeof(pr0));
661 		pr0.ndpr_ifp = ifp;
662 		pr0.ndpr_plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
663 		    NULL);
664 		if (pr0.ndpr_plen == 128) {
665 			break;	/* we don't need to install a host route. */
666 		}
667 		pr0.ndpr_prefix = ifra->ifra_addr;
668 		pr0.ndpr_mask = ifra->ifra_prefixmask.sin6_addr;
669 		/* apply the mask for safety. */
670 		for (i = 0; i < 4; i++) {
671 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
672 			    ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
673 		}
674 		/*
675 		 * XXX: since we don't have an API to set prefix (not address)
676 		 * lifetimes, we just use the same lifetimes as addresses.
677 		 * The (temporarily) installed lifetimes can be overridden by
678 		 * later advertised RAs (when accept_rtadv is non 0), which is
679 		 * an intended behavior.
680 		 */
681 		pr0.ndpr_raf_onlink = 1; /* should be configurable? */
682 		pr0.ndpr_raf_auto =
683 		    ((ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0);
684 		pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
685 		pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;
686 
687 		/* add the prefix if not yet. */
688 		if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
689 			/*
690 			 * nd6_prelist_add will install the corresponding
691 			 * interface route.
692 			 */
693 			if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
694 				return (error);
695 			if (pr == NULL) {
696 				log(LOG_ERR, "nd6_prelist_add succeeded but "
697 				    "no prefix\n");
698 				return (EINVAL); /* XXX panic here? */
699 			}
700 		}
701 
702 		/* relate the address to the prefix */
703 		if (ia->ia6_ndpr == NULL) {
704 			ia->ia6_ndpr = pr;
705 			pr->ndpr_refcnt++;
706 		}
707 
708 		/*
709 		 * this might affect the status of autoconfigured addresses,
710 		 * that is, this address might make other addresses detached.
711 		 */
712 		pfxlist_onlink_check();
713 
714 #ifdef PFIL_HOOKS
715 		(void)pfil_run_hooks(&if_pfil, (struct mbuf **)SIOCAIFADDR_IN6,
716 		    ifp, PFIL_IFADDR);
717 #endif
718 
719 		break;
720 	}
721 
722 	case SIOCDIFADDR_IN6:
723 	{
724 		int i = 0, purgeprefix = 0;
725 		struct nd_prefix pr0, *pr = NULL;
726 
727 		/*
728 		 * If the address being deleted is the only one that owns
729 		 * the corresponding prefix, expire the prefix as well.
730 		 * XXX: theoretically, we don't have to worry about such
731 		 * relationship, since we separate the address management
732 		 * and the prefix management.  We do this, however, to provide
733 		 * as much backward compatibility as possible in terms of
734 		 * the ioctl operation.
735 		 */
736 		bzero(&pr0, sizeof(pr0));
737 		pr0.ndpr_ifp = ifp;
738 		pr0.ndpr_plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr,
739 		    NULL);
740 		if (pr0.ndpr_plen == 128)
741 			goto purgeaddr;
742 		pr0.ndpr_prefix = ia->ia_addr;
743 		pr0.ndpr_mask = ia->ia_prefixmask.sin6_addr;
744 		for (i = 0; i < 4; i++) {
745 			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
746 			    ia->ia_prefixmask.sin6_addr.s6_addr32[i];
747 		}
748 		if ((pr = nd6_prefix_lookup(&pr0)) != NULL &&
749 		    pr == ia->ia6_ndpr) {
750 			pr->ndpr_refcnt--;
751 			if (pr->ndpr_refcnt == 0)
752 				purgeprefix = 1;
753 		}
754 
755 	  purgeaddr:
756 		in6_purgeaddr(&ia->ia_ifa);
757 		if (pr && purgeprefix)
758 			prelist_remove(pr);
759 #ifdef PFIL_HOOKS
760 		(void)pfil_run_hooks(&if_pfil, (struct mbuf **)SIOCDIFADDR_IN6,
761 		    ifp, PFIL_IFADDR);
762 #endif
763 		break;
764 	}
765 
766 	default:
767 		if (ifp == NULL || ifp->if_ioctl == 0)
768 			return (EOPNOTSUPP);
769 		return ((*ifp->if_ioctl)(ifp, cmd, data));
770 	}
771 
772 	return (0);
773 }
774 
775 /*
776  * Update parameters of an IPv6 interface address.
777  * If necessary, a new entry is created and linked into address chains.
778  * This function is separated from in6_control().
779  * XXX: should this be performed under splnet()?
780  */
781 int
782 in6_update_ifa(ifp, ifra, ia)
783 	struct ifnet *ifp;
784 	struct in6_aliasreq *ifra;
785 	struct in6_ifaddr *ia;
786 {
787 	int error = 0, hostIsNew = 0, plen = -1;
788 	struct in6_ifaddr *oia;
789 	struct sockaddr_in6 dst6;
790 	struct in6_addrlifetime *lt;
791 	struct in6_multi_mship *imm;
792 	struct rtentry *rt;
793 
794 	/* Validate parameters */
795 	if (ifp == NULL || ifra == NULL) /* this maybe redundant */
796 		return (EINVAL);
797 
798 	/*
799 	 * The destination address for a p2p link must have a family
800 	 * of AF_UNSPEC or AF_INET6.
801 	 */
802 	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
803 	    ifra->ifra_dstaddr.sin6_family != AF_INET6 &&
804 	    ifra->ifra_dstaddr.sin6_family != AF_UNSPEC)
805 		return (EAFNOSUPPORT);
806 	/*
807 	 * validate ifra_prefixmask.  don't check sin6_family, netmask
808 	 * does not carry fields other than sin6_len.
809 	 */
810 	if (ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6))
811 		return (EINVAL);
812 	/*
813 	 * Because the IPv6 address architecture is classless, we require
814 	 * users to specify a (non 0) prefix length (mask) for a new address.
815 	 * We also require the prefix (when specified) mask is valid, and thus
816 	 * reject a non-consecutive mask.
817 	 */
818 	if (ia == NULL && ifra->ifra_prefixmask.sin6_len == 0)
819 		return (EINVAL);
820 	if (ifra->ifra_prefixmask.sin6_len != 0) {
821 		plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
822 		    (u_char *)&ifra->ifra_prefixmask +
823 		    ifra->ifra_prefixmask.sin6_len);
824 		if (plen <= 0)
825 			return (EINVAL);
826 	} else {
827 		/*
828 		 * In this case, ia must not be NULL.  We just use its prefix
829 		 * length.
830 		 */
831 		plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
832 	}
833 	/*
834 	 * If the destination address on a p2p interface is specified,
835 	 * and the address is a scoped one, validate/set the scope
836 	 * zone identifier.
837 	 */
838 	dst6 = ifra->ifra_dstaddr;
839 	if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) != 0 &&
840 	    (dst6.sin6_family == AF_INET6)) {
841 		struct in6_addr in6_tmp;
842 		u_int32_t zoneid;
843 
844 		in6_tmp = dst6.sin6_addr;
845 		if (in6_setscope(&in6_tmp, ifp, &zoneid))
846 			return (EINVAL); /* XXX: should be impossible */
847 
848 		if (dst6.sin6_scope_id != 0) {
849 			if (dst6.sin6_scope_id != zoneid)
850 				return (EINVAL);
851 		} else		/* user omit to specify the ID. */
852 			dst6.sin6_scope_id = zoneid;
853 
854 		/* convert into the internal form */
855 		if (sa6_embedscope(&dst6, 0))
856 			return (EINVAL); /* XXX: should be impossible */
857 	}
858 	/*
859 	 * The destination address can be specified only for a p2p or a
860 	 * loopback interface.  If specified, the corresponding prefix length
861 	 * must be 128.
862 	 */
863 	if (ifra->ifra_dstaddr.sin6_family == AF_INET6) {
864 #ifdef FORCE_P2PPLEN
865 		int i;
866 #endif
867 
868 		if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) == 0) {
869 			/* XXX: noisy message */
870 			nd6log((LOG_INFO, "in6_update_ifa: a destination can "
871 			    "be specified for a p2p or a loopback IF only\n"));
872 			return (EINVAL);
873 		}
874 		if (plen != 128) {
875 			nd6log((LOG_INFO, "in6_update_ifa: prefixlen should "
876 			    "be 128 when dstaddr is specified\n"));
877 #ifdef FORCE_P2PPLEN
878 			/*
879 			 * To be compatible with old configurations,
880 			 * such as ifconfig gif0 inet6 2001::1 2001::2
881 			 * prefixlen 126, we override the specified
882 			 * prefixmask as if the prefix length was 128.
883 			 */
884 			ifra->ifra_prefixmask.sin6_len =
885 			    sizeof(struct sockaddr_in6);
886 			for (i = 0; i < 4; i++)
887 				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i] =
888 				    0xffffffff;
889 			plen = 128;
890 #else
891 			return (EINVAL);
892 #endif
893 		}
894 	}
895 	/* lifetime consistency check */
896 	lt = &ifra->ifra_lifetime;
897 	if (lt->ia6t_pltime > lt->ia6t_vltime)
898 		return (EINVAL);
899 	if (lt->ia6t_vltime == 0) {
900 		/*
901 		 * the following log might be noisy, but this is a typical
902 		 * configuration mistake or a tool's bug.
903 		 */
904 		nd6log((LOG_INFO,
905 		    "in6_update_ifa: valid lifetime is 0 for %s\n",
906 		    ip6_sprintf(&ifra->ifra_addr.sin6_addr)));
907 
908 		if (ia == NULL)
909 			return (0); /* there's nothing to do */
910 	}
911 
912 	/*
913 	 * If this is a new address, allocate a new ifaddr and link it
914 	 * into chains.
915 	 */
916 	if (ia == NULL) {
917 		hostIsNew = 1;
918 		/*
919 		 * When in6_update_ifa() is called in a process of a received
920 		 * RA, it is called under an interrupt context.  So, we should
921 		 * call malloc with M_NOWAIT.
922 		 */
923 		ia = (struct in6_ifaddr *) malloc(sizeof(*ia), M_IFADDR,
924 		    M_NOWAIT);
925 		if (ia == NULL)
926 			return (ENOBUFS);
927 		bzero((caddr_t)ia, sizeof(*ia));
928 		LIST_INIT(&ia->ia6_memberships);
929 		/* Initialize the address and masks, and put time stamp */
930 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
931 		ia->ia_addr.sin6_family = AF_INET6;
932 		ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
933 		ia->ia6_createtime = ia->ia6_updatetime = time.tv_sec;
934 		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
935 			/*
936 			 * XXX: some functions expect that ifa_dstaddr is not
937 			 * NULL for p2p interfaces.
938 			 */
939 			ia->ia_ifa.ifa_dstaddr =
940 			    (struct sockaddr *)&ia->ia_dstaddr;
941 		} else {
942 			ia->ia_ifa.ifa_dstaddr = NULL;
943 		}
944 		ia->ia_ifa.ifa_netmask =
945 		    (struct sockaddr *)&ia->ia_prefixmask;
946 
947 		ia->ia_ifp = ifp;
948 		if ((oia = in6_ifaddr) != NULL) {
949 			for ( ; oia->ia_next; oia = oia->ia_next)
950 				continue;
951 			oia->ia_next = ia;
952 		} else
953 			in6_ifaddr = ia;
954 		/* gain a refcnt for the link from in6_ifaddr */
955 		IFAREF(&ia->ia_ifa);
956 
957 		TAILQ_INSERT_TAIL(&ifp->if_addrlist, &ia->ia_ifa,
958 				  ifa_list);
959 		/* gain another refcnt for the link from if_addrlist */
960 		IFAREF(&ia->ia_ifa);
961 	}
962 
963 	/* set prefix mask */
964 	if (ifra->ifra_prefixmask.sin6_len) {
965 		/*
966 		 * We prohibit changing the prefix length of an existing
967 		 * address, because
968 		 * + such an operation should be rare in IPv6, and
969 		 * + the operation would confuse prefix management.
970 		 */
971 		if (ia->ia_prefixmask.sin6_len &&
972 		    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL) != plen) {
973 			nd6log((LOG_INFO, "in6_update_ifa: the prefix length of an"
974 			    " existing (%s) address should not be changed\n",
975 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
976 			error = EINVAL;
977 			goto unlink;
978 		}
979 		ia->ia_prefixmask = ifra->ifra_prefixmask;
980 	}
981 
982 	/*
983 	 * If a new destination address is specified, scrub the old one and
984 	 * install the new destination.  Note that the interface must be
985 	 * p2p or loopback (see the check above.)
986 	 */
987 	if (dst6.sin6_family == AF_INET6 &&
988 	    !IN6_ARE_ADDR_EQUAL(&dst6.sin6_addr, &ia->ia_dstaddr.sin6_addr)) {
989 		if ((ia->ia_flags & IFA_ROUTE) != 0 &&
990 		    rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST) != 0) {
991 			nd6log((LOG_ERR, "in6_update_ifa: failed to remove "
992 			    "a route to the old destination: %s\n",
993 			    ip6_sprintf(&ia->ia_addr.sin6_addr)));
994 			/* proceed anyway... */
995 		} else
996 			ia->ia_flags &= ~IFA_ROUTE;
997 		ia->ia_dstaddr = dst6;
998 	}
999 
1000 	/*
1001 	 * Set lifetimes.  We do not refer to ia6t_expire and ia6t_preferred
1002 	 * to see if the address is deprecated or invalidated, but initialize
1003 	 * these members for applications.
1004 	 */
1005 	ia->ia6_lifetime = ifra->ifra_lifetime;
1006 	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
1007 		ia->ia6_lifetime.ia6t_expire =
1008 		    time.tv_sec + ia->ia6_lifetime.ia6t_vltime;
1009 	} else
1010 		ia->ia6_lifetime.ia6t_expire = 0;
1011 	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
1012 		ia->ia6_lifetime.ia6t_preferred =
1013 		    time.tv_sec + ia->ia6_lifetime.ia6t_pltime;
1014 	} else
1015 		ia->ia6_lifetime.ia6t_preferred = 0;
1016 
1017 	/* reset the interface and routing table appropriately. */
1018 	if ((error = in6_ifinit(ifp, ia, &ifra->ifra_addr, hostIsNew)) != 0)
1019 		goto unlink;
1020 
1021 	/*
1022 	 * configure address flags.
1023 	 */
1024 	ia->ia6_flags = ifra->ifra_flags;
1025 	ia->ia6_flags &= ~IN6_IFF_DUPLICATED;	/* safety */
1026 	/*
1027 	 * backward compatibility - if IN6_IFF_DEPRECATED is set from the
1028 	 * userland, make it deprecated.
1029 	 */
1030 	if ((ifra->ifra_flags & IN6_IFF_DEPRECATED) != 0) {
1031 		ia->ia6_lifetime.ia6t_pltime = 0;
1032 		ia->ia6_lifetime.ia6t_preferred = time.tv_sec;
1033 	}
1034 
1035 	/*
1036 	 * Perform DAD, if needed.
1037 	 * XXX It may be of use, if we can administratively
1038 	 * disable DAD.
1039 	 */
1040 	if (in6if_do_dad(ifp) && hostIsNew &&
1041 	    (ifra->ifra_flags & IN6_IFF_NODAD) == 0) {
1042 		ia->ia6_flags |= IN6_IFF_TENTATIVE;
1043 		nd6_dad_start((struct ifaddr *)ia, NULL);
1044 	}
1045 
1046 	/*
1047 	 * We are done if we have simply modified an existing address.
1048 	 */
1049 	if (!hostIsNew)
1050 		return (error);
1051 
1052 	/*
1053 	 * Beyond this point, we should call in6_purgeaddr upon an error,
1054 	 * not just go to unlink.
1055 	 */
1056 
1057 	/* join necessary multiast groups */
1058 	if ((ifp->if_flags & IFF_MULTICAST) != 0) {
1059 		struct sockaddr_in6 mltaddr, mltmask;
1060 		struct in6_addr llsol;
1061 
1062 		/* join solicited multicast addr for new host id */
1063 		bzero(&llsol, sizeof(struct in6_addr));
1064 		llsol.s6_addr16[0] = htons(0xff02);
1065 		llsol.s6_addr32[1] = 0;
1066 		llsol.s6_addr32[2] = htonl(1);
1067 		llsol.s6_addr32[3] = ifra->ifra_addr.sin6_addr.s6_addr32[3];
1068 		llsol.s6_addr8[12] = 0xff;
1069 		if ((error = in6_setscope(&llsol, ifp, NULL)) != 0) {
1070 			/* XXX: should not happen */
1071 			log(LOG_ERR, "in6_update_ifa: "
1072 			    "in6_setscope failed\n");
1073 			goto cleanup;
1074 		}
1075 		imm = in6_joingroup(ifp, &llsol, &error);
1076 		if (!imm) {
1077 			nd6log((LOG_ERR,
1078 			    "in6_update_ifa: addmulti "
1079 			    "failed for %s on %s (errno=%d)\n",
1080 			    ip6_sprintf(&llsol), if_name(ifp), error));
1081 			goto cleanup;
1082 		}
1083 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1084 
1085 		bzero(&mltmask, sizeof(mltmask));
1086 		mltmask.sin6_len = sizeof(struct sockaddr_in6);
1087 		mltmask.sin6_family = AF_INET6;
1088 		mltmask.sin6_addr = in6mask32;
1089 
1090 		/*
1091 		 * join link-local all-nodes address
1092 		 */
1093 		bzero(&mltaddr, sizeof(mltaddr));
1094 		mltaddr.sin6_len = sizeof(struct sockaddr_in6);
1095 		mltaddr.sin6_family = AF_INET6;
1096 		mltaddr.sin6_addr = in6addr_linklocal_allnodes;
1097 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) !=
1098 		    0)
1099 			goto cleanup; /* XXX: should not fail */
1100 
1101 		/*
1102 		 * XXX: do we really need this automatic routes?
1103 		 * We should probably reconsider this stuff.  Most applications
1104 		 * actually do not need the routes, since they usually specify
1105 		 * the outgoing interface.
1106 		 */
1107 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1108 		if (rt) {
1109 			/*
1110 			 * 32bit came from "mltmask"
1111 			 */
1112 			if (memcmp(&mltaddr.sin6_addr,
1113 			    &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
1114 			    32 / 8)) {
1115 				RTFREE(rt);
1116 				rt = NULL;
1117 			}
1118 		}
1119 		if (!rt) {
1120 			struct rt_addrinfo info;
1121 
1122 			bzero(&info, sizeof(info));
1123 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1124 			info.rti_info[RTAX_GATEWAY] =
1125 			    (struct sockaddr *)&ia->ia_addr;
1126 			info.rti_info[RTAX_NETMASK] =
1127 			    (struct sockaddr *)&mltmask;
1128 			info.rti_info[RTAX_IFA] =
1129 			    (struct sockaddr *)&ia->ia_addr;
1130 			/* XXX: we need RTF_CLONING to fake nd6_rtrequest */
1131 			info.rti_flags = RTF_UP | RTF_CLONING;
1132 			error = rtrequest1(RTM_ADD, &info, NULL);
1133 			if (error)
1134 				goto cleanup;
1135 		} else {
1136 			RTFREE(rt);
1137 		}
1138 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error);
1139 		if (!imm) {
1140 			nd6log((LOG_WARNING,
1141 			    "in6_update_ifa: addmulti failed for "
1142 			    "%s on %s (errno=%d)\n",
1143 			    ip6_sprintf(&mltaddr.sin6_addr),
1144 			    if_name(ifp), error));
1145 			goto cleanup;
1146 		}
1147 		LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
1148 
1149 		/*
1150 		 * join node information group address
1151 		 */
1152 		if (in6_nigroup(ifp, hostname, hostnamelen, &mltaddr) == 0) {
1153 			imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error);
1154 			if (!imm) {
1155 				nd6log((LOG_WARNING, "in6_update_ifa: "
1156 				    "addmulti failed for %s on %s (errno=%d)\n",
1157 				    ip6_sprintf(&mltaddr.sin6_addr),
1158 				    if_name(ifp), error));
1159 				/* XXX not very fatal, go on... */
1160 			} else {
1161 				LIST_INSERT_HEAD(&ia->ia6_memberships,
1162 				    imm, i6mm_chain);
1163 			}
1164 		}
1165 
1166 
1167 		/*
1168 		 * join interface-local all-nodes address.
1169 		 * (ff01::1%ifN, and ff01::%ifN/32)
1170 		 */
1171 		mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
1172 		if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL))
1173 		    != 0)
1174 			goto cleanup; /* XXX: should not fail */
1175 
1176 		/* XXX: again, do we really need the route? */
1177 		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
1178 		if (rt) {
1179 			/* 32bit came from "mltmask" */
1180 			if (memcmp(&mltaddr.sin6_addr,
1181 			    &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
1182 			    32 / 8)) {
1183 				RTFREE(rt);
1184 				rt = NULL;
1185 			}
1186 		}
1187 		if (!rt) {
1188 			struct rt_addrinfo info;
1189 
1190 			bzero(&info, sizeof(info));
1191 			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
1192 			info.rti_info[RTAX_GATEWAY] =
1193 			    (struct sockaddr *)&ia->ia_addr;
1194 			info.rti_info[RTAX_NETMASK] =
1195 			    (struct sockaddr *)&mltmask;
1196 			info.rti_info[RTAX_IFA] =
1197 			    (struct sockaddr *)&ia->ia_addr;
1198 			info.rti_flags = RTF_UP | RTF_CLONING;
1199 			error = rtrequest1(RTM_ADD, &info, NULL);
1200 			if (error)
1201 				goto cleanup;
1202 		} else {
1203 			RTFREE(rt);
1204 		}
1205 		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error);
1206 		if (!imm) {
1207 			nd6log((LOG_WARNING, "in6_update_ifa: "
1208 			    "addmulti failed for %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 	return (error);
1217 
1218   unlink:
1219 	/*
1220 	 * XXX: if a change of an existing address failed, keep the entry
1221 	 * anyway.
1222 	 */
1223 	if (hostIsNew)
1224 		in6_unlink_ifa(ia, ifp);
1225 	return (error);
1226 
1227   cleanup:
1228 	in6_purgeaddr(&ia->ia_ifa);
1229 	return error;
1230 }
1231 
1232 void
1233 in6_purgeaddr(ifa)
1234 	struct ifaddr *ifa;
1235 {
1236 	struct ifnet *ifp = ifa->ifa_ifp;
1237 	struct in6_ifaddr *ia = (struct in6_ifaddr *) ifa;
1238 	struct in6_multi_mship *imm;
1239 
1240 	/* stop DAD processing */
1241 	nd6_dad_stop(ifa);
1242 
1243 	/*
1244 	 * delete route to the destination of the address being purged.
1245 	 * The interface must be p2p or loopback in this case.
1246 	 */
1247 	if ((ia->ia_flags & IFA_ROUTE) != 0 && ia->ia_dstaddr.sin6_len != 0) {
1248 		int e;
1249 
1250 		if ((e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
1251 		    != 0) {
1252 			log(LOG_ERR, "in6_purgeaddr: failed to remove "
1253 			    "a route to the p2p destination: %s on %s, "
1254 			    "errno=%d\n",
1255 			    ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
1256 			    e);
1257 			/* proceed anyway... */
1258 		} else
1259 			ia->ia_flags &= ~IFA_ROUTE;
1260 	}
1261 
1262 	/* Remove ownaddr's loopback rtentry, if it exists. */
1263 	in6_ifremloop(&(ia->ia_ifa));
1264 
1265 	/*
1266 	 * leave from multicast groups we have joined for the interface
1267 	 */
1268 	while ((imm = ia->ia6_memberships.lh_first) != NULL) {
1269 		LIST_REMOVE(imm, i6mm_chain);
1270 		in6_leavegroup(imm);
1271 	}
1272 
1273 	in6_unlink_ifa(ia, ifp);
1274 }
1275 
1276 static void
1277 in6_unlink_ifa(ia, ifp)
1278 	struct in6_ifaddr *ia;
1279 	struct ifnet *ifp;
1280 {
1281 	struct in6_ifaddr *oia;
1282 	int	s = splnet();
1283 
1284 	TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
1285 	/* release a refcnt for the link from if_addrlist */
1286 	IFAFREE(&ia->ia_ifa);
1287 
1288 	oia = ia;
1289 	if (oia == (ia = in6_ifaddr))
1290 		in6_ifaddr = ia->ia_next;
1291 	else {
1292 		while (ia->ia_next && (ia->ia_next != oia))
1293 			ia = ia->ia_next;
1294 		if (ia->ia_next)
1295 			ia->ia_next = oia->ia_next;
1296 		else {
1297 			/* search failed */
1298 			printf("Couldn't unlink in6_ifaddr from in6_ifaddr\n");
1299 		}
1300 	}
1301 
1302 	if (oia->ia6_multiaddrs.lh_first != NULL) {
1303 		/*
1304 		 * XXX thorpej@NetBSD.org -- if the interface is going
1305 		 * XXX away, don't save the multicast entries, delete them!
1306 		 */
1307 		if (oia->ia_ifa.ifa_ifp->if_output == if_nulloutput) {
1308 			struct in6_multi *in6m;
1309 
1310 			while ((in6m =
1311 			    LIST_FIRST(&oia->ia6_multiaddrs)) != NULL)
1312 				in6_delmulti(in6m);
1313 		} else
1314 			in6_savemkludge(oia);
1315 	}
1316 
1317 	/*
1318 	 * When an autoconfigured address is being removed, release the
1319 	 * reference to the base prefix.  Also, since the release might
1320 	 * affect the status of other (detached) addresses, call
1321 	 * pfxlist_onlink_check().
1322 	 */
1323 	if ((oia->ia6_flags & IN6_IFF_AUTOCONF) != 0) {
1324 		if (oia->ia6_ndpr == NULL) {
1325 			log(LOG_NOTICE, "in6_unlink_ifa: autoconf'ed address "
1326 			    "%p has no prefix\n", oia);
1327 		} else {
1328 			oia->ia6_ndpr->ndpr_refcnt--;
1329 			oia->ia6_flags &= ~IN6_IFF_AUTOCONF;
1330 			oia->ia6_ndpr = NULL;
1331 		}
1332 
1333 		pfxlist_onlink_check();
1334 	}
1335 
1336 	/*
1337 	 * release another refcnt for the link from in6_ifaddr.
1338 	 * Note that we should decrement the refcnt at least once for all *BSD.
1339 	 */
1340 	IFAFREE(&oia->ia_ifa);
1341 
1342 	splx(s);
1343 }
1344 
1345 void
1346 in6_purgeif(ifp)
1347 	struct ifnet *ifp;
1348 {
1349 	struct ifaddr *ifa, *nifa;
1350 
1351 	for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa != NULL; ifa = nifa)
1352 	{
1353 		nifa = TAILQ_NEXT(ifa, ifa_list);
1354 		if (ifa->ifa_addr->sa_family != AF_INET6)
1355 			continue;
1356 		in6_purgeaddr(ifa);
1357 	}
1358 
1359 	in6_ifdetach(ifp);
1360 }
1361 
1362 /*
1363  * SIOC[GAD]LIFADDR.
1364  *	SIOCGLIFADDR: get first address. (?)
1365  *	SIOCGLIFADDR with IFLR_PREFIX:
1366  *		get first address that matches the specified prefix.
1367  *	SIOCALIFADDR: add the specified address.
1368  *	SIOCALIFADDR with IFLR_PREFIX:
1369  *		add the specified prefix, filling hostid part from
1370  *		the first link-local address.  prefixlen must be <= 64.
1371  *	SIOCDLIFADDR: delete the specified address.
1372  *	SIOCDLIFADDR with IFLR_PREFIX:
1373  *		delete the first address that matches the specified prefix.
1374  * return values:
1375  *	EINVAL on invalid parameters
1376  *	EADDRNOTAVAIL on prefix match failed/specified address not found
1377  *	other values may be returned from in6_ioctl()
1378  *
1379  * NOTE: SIOCALIFADDR(with IFLR_PREFIX set) allows prefixlen less than 64.
1380  * this is to accomodate address naming scheme other than RFC2374,
1381  * in the future.
1382  * RFC2373 defines interface id to be 64bit, but it allows non-RFC2374
1383  * address encoding scheme. (see figure on page 8)
1384  */
1385 static int
1386 in6_lifaddr_ioctl(so, cmd, data, ifp, p)
1387 	struct socket *so;
1388 	u_long cmd;
1389 	caddr_t	data;
1390 	struct ifnet *ifp;
1391 	struct proc *p;
1392 {
1393 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
1394 	struct ifaddr *ifa;
1395 	struct sockaddr *sa;
1396 
1397 	/* sanity checks */
1398 	if (!data || !ifp) {
1399 		panic("invalid argument to in6_lifaddr_ioctl");
1400 		/* NOTREACHED */
1401 	}
1402 
1403 	switch (cmd) {
1404 	case SIOCGLIFADDR:
1405 		/* address must be specified on GET with IFLR_PREFIX */
1406 		if ((iflr->flags & IFLR_PREFIX) == 0)
1407 			break;
1408 		/* FALLTHROUGH */
1409 	case SIOCALIFADDR:
1410 	case SIOCDLIFADDR:
1411 		/* address must be specified on ADD and DELETE */
1412 		sa = (struct sockaddr *)&iflr->addr;
1413 		if (sa->sa_family != AF_INET6)
1414 			return EINVAL;
1415 		if (sa->sa_len != sizeof(struct sockaddr_in6))
1416 			return EINVAL;
1417 		/* XXX need improvement */
1418 		sa = (struct sockaddr *)&iflr->dstaddr;
1419 		if (sa->sa_family && sa->sa_family != AF_INET6)
1420 			return EINVAL;
1421 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in6))
1422 			return EINVAL;
1423 		break;
1424 	default: /* shouldn't happen */
1425 #if 0
1426 		panic("invalid cmd to in6_lifaddr_ioctl");
1427 		/* NOTREACHED */
1428 #else
1429 		return EOPNOTSUPP;
1430 #endif
1431 	}
1432 	if (sizeof(struct in6_addr) * 8 < iflr->prefixlen)
1433 		return EINVAL;
1434 
1435 	switch (cmd) {
1436 	case SIOCALIFADDR:
1437 	    {
1438 		struct in6_aliasreq ifra;
1439 		struct in6_addr *xhostid = NULL;
1440 		int prefixlen;
1441 
1442 		if ((iflr->flags & IFLR_PREFIX) != 0) {
1443 			struct sockaddr_in6 *sin6;
1444 
1445 			/*
1446 			 * xhostid is to fill in the hostid part of the
1447 			 * address.  xhostid points to the first link-local
1448 			 * address attached to the interface.
1449 			 */
1450 			ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0);
1451 			if (!ifa)
1452 				return EADDRNOTAVAIL;
1453 			xhostid = IFA_IN6(ifa);
1454 
1455 		 	/* prefixlen must be <= 64. */
1456 			if (64 < iflr->prefixlen)
1457 				return EINVAL;
1458 			prefixlen = iflr->prefixlen;
1459 
1460 			/* hostid part must be zero. */
1461 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1462 			if (sin6->sin6_addr.s6_addr32[2] != 0
1463 			 || sin6->sin6_addr.s6_addr32[3] != 0) {
1464 				return EINVAL;
1465 			}
1466 		} else
1467 			prefixlen = iflr->prefixlen;
1468 
1469 		/* copy args to in6_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
1470 		bzero(&ifra, sizeof(ifra));
1471 		bcopy(iflr->iflr_name, ifra.ifra_name, sizeof(ifra.ifra_name));
1472 
1473 		bcopy(&iflr->addr, &ifra.ifra_addr,
1474 		    ((struct sockaddr *)&iflr->addr)->sa_len);
1475 		if (xhostid) {
1476 			/* fill in hostid part */
1477 			ifra.ifra_addr.sin6_addr.s6_addr32[2] =
1478 			    xhostid->s6_addr32[2];
1479 			ifra.ifra_addr.sin6_addr.s6_addr32[3] =
1480 			    xhostid->s6_addr32[3];
1481 		}
1482 
1483 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) { /* XXX */
1484 			bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
1485 			    ((struct sockaddr *)&iflr->dstaddr)->sa_len);
1486 			if (xhostid) {
1487 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[2] =
1488 				    xhostid->s6_addr32[2];
1489 				ifra.ifra_dstaddr.sin6_addr.s6_addr32[3] =
1490 				    xhostid->s6_addr32[3];
1491 			}
1492 		}
1493 
1494 		ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
1495 		in6_prefixlen2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);
1496 
1497 		ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
1498 		return in6_control(so, SIOCAIFADDR_IN6, (caddr_t)&ifra, ifp, p);
1499 	    }
1500 	case SIOCGLIFADDR:
1501 	case SIOCDLIFADDR:
1502 	    {
1503 		struct in6_ifaddr *ia;
1504 		struct in6_addr mask, candidate, match;
1505 		struct sockaddr_in6 *sin6;
1506 		int cmp;
1507 
1508 		bzero(&mask, sizeof(mask));
1509 		if (iflr->flags & IFLR_PREFIX) {
1510 			/* lookup a prefix rather than address. */
1511 			in6_prefixlen2mask(&mask, iflr->prefixlen);
1512 
1513 			sin6 = (struct sockaddr_in6 *)&iflr->addr;
1514 			bcopy(&sin6->sin6_addr, &match, sizeof(match));
1515 			match.s6_addr32[0] &= mask.s6_addr32[0];
1516 			match.s6_addr32[1] &= mask.s6_addr32[1];
1517 			match.s6_addr32[2] &= mask.s6_addr32[2];
1518 			match.s6_addr32[3] &= mask.s6_addr32[3];
1519 
1520 			/* if you set extra bits, that's wrong */
1521 			if (bcmp(&match, &sin6->sin6_addr, sizeof(match)))
1522 				return EINVAL;
1523 
1524 			cmp = 1;
1525 		} else {
1526 			if (cmd == SIOCGLIFADDR) {
1527 				/* on getting an address, take the 1st match */
1528 				cmp = 0;	/* XXX */
1529 			} else {
1530 				/* on deleting an address, do exact match */
1531 				in6_prefixlen2mask(&mask, 128);
1532 				sin6 = (struct sockaddr_in6 *)&iflr->addr;
1533 				bcopy(&sin6->sin6_addr, &match, sizeof(match));
1534 
1535 				cmp = 1;
1536 			}
1537 		}
1538 
1539 		for (ifa = ifp->if_addrlist.tqh_first;
1540 		     ifa;
1541 		     ifa = ifa->ifa_list.tqe_next)
1542 		{
1543 			if (ifa->ifa_addr->sa_family != AF_INET6)
1544 				continue;
1545 			if (!cmp)
1546 				break;
1547 
1548 			/*
1549 			 * XXX: this is adhoc, but is necessary to allow
1550 			 * a user to specify fe80::/64 (not /10) for a
1551 			 * link-local address.
1552 			 */
1553 			bcopy(IFA_IN6(ifa), &candidate, sizeof(candidate));
1554 			in6_clearscope(&candidate);
1555 			candidate.s6_addr32[0] &= mask.s6_addr32[0];
1556 			candidate.s6_addr32[1] &= mask.s6_addr32[1];
1557 			candidate.s6_addr32[2] &= mask.s6_addr32[2];
1558 			candidate.s6_addr32[3] &= mask.s6_addr32[3];
1559 			if (IN6_ARE_ADDR_EQUAL(&candidate, &match))
1560 				break;
1561 		}
1562 		if (!ifa)
1563 			return EADDRNOTAVAIL;
1564 		ia = ifa2ia6(ifa);
1565 
1566 		if (cmd == SIOCGLIFADDR) {
1567 			int error;
1568 
1569 			/* fill in the if_laddrreq structure */
1570 			bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin6_len);
1571 			error = sa6_recoverscope(
1572 			    (struct sockaddr_in6 *)&iflr->addr);
1573 			if (error != 0)
1574 				return (error);
1575 
1576 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1577 				bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
1578 				    ia->ia_dstaddr.sin6_len);
1579 				error = sa6_recoverscope(
1580 				    (struct sockaddr_in6 *)&iflr->dstaddr);
1581 				if (error != 0)
1582 					return (error);
1583 			} else
1584 				bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
1585 
1586 			iflr->prefixlen =
1587 			    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
1588 
1589 			iflr->flags = ia->ia6_flags;	/* XXX */
1590 
1591 			return 0;
1592 		} else {
1593 			struct in6_aliasreq ifra;
1594 
1595 			/* fill in6_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
1596 			bzero(&ifra, sizeof(ifra));
1597 			bcopy(iflr->iflr_name, ifra.ifra_name,
1598 			    sizeof(ifra.ifra_name));
1599 
1600 			bcopy(&ia->ia_addr, &ifra.ifra_addr,
1601 			    ia->ia_addr.sin6_len);
1602 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
1603 				bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
1604 				    ia->ia_dstaddr.sin6_len);
1605 			} else {
1606 				bzero(&ifra.ifra_dstaddr,
1607 				    sizeof(ifra.ifra_dstaddr));
1608 			}
1609 			bcopy(&ia->ia_prefixmask, &ifra.ifra_dstaddr,
1610 			    ia->ia_prefixmask.sin6_len);
1611 
1612 			ifra.ifra_flags = ia->ia6_flags;
1613 			return in6_control(so, SIOCDIFADDR_IN6, (caddr_t)&ifra,
1614 			    ifp, p);
1615 		}
1616 	    }
1617 	}
1618 
1619 	return EOPNOTSUPP;	/* just for safety */
1620 }
1621 
1622 /*
1623  * Initialize an interface's intetnet6 address
1624  * and routing table entry.
1625  */
1626 static int
1627 in6_ifinit(ifp, ia, sin6, newhost)
1628 	struct ifnet *ifp;
1629 	struct in6_ifaddr *ia;
1630 	struct sockaddr_in6 *sin6;
1631 	int newhost;
1632 {
1633 	int	error = 0, plen, ifacount = 0;
1634 	int	s = splnet();
1635 	struct ifaddr *ifa;
1636 
1637 	/*
1638 	 * Give the interface a chance to initialize
1639 	 * if this is its first address,
1640 	 * and to validate the address if necessary.
1641 	 */
1642 	for (ifa = ifp->if_addrlist.tqh_first; ifa;
1643 	     ifa = ifa->ifa_list.tqe_next)
1644 	{
1645 		if (ifa->ifa_addr == NULL)
1646 			continue;	/* just for safety */
1647 		if (ifa->ifa_addr->sa_family != AF_INET6)
1648 			continue;
1649 		ifacount++;
1650 	}
1651 
1652 	ia->ia_addr = *sin6;
1653 
1654 	if (ifacount <= 1 && ifp->if_ioctl &&
1655 	    (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
1656 		splx(s);
1657 		return (error);
1658 	}
1659 	splx(s);
1660 
1661 	ia->ia_ifa.ifa_metric = ifp->if_metric;
1662 
1663 	/* we could do in(6)_socktrim here, but just omit it at this moment. */
1664 
1665 	/*
1666 	 * Special case:
1667 	 * If the destination address is specified for a point-to-point
1668 	 * interface, install a route to the destination as an interface
1669 	 * direct route.
1670 	 */
1671 	plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
1672 	if (plen == 128 && ia->ia_dstaddr.sin6_family == AF_INET6) {
1673 		if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD,
1674 				    RTF_UP | RTF_HOST)) != 0)
1675 			return (error);
1676 		ia->ia_flags |= IFA_ROUTE;
1677 	}
1678 
1679 	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
1680 	if (newhost) {
1681 		/* set the rtrequest function to create llinfo */
1682 		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
1683 		in6_ifaddloop(&(ia->ia_ifa));
1684 	}
1685 
1686 	if (ifp->if_flags & IFF_MULTICAST)
1687 		in6_restoremkludge(ia, ifp);
1688 
1689 	return (error);
1690 }
1691 
1692 /*
1693  * Multicast address kludge:
1694  * If there were any multicast addresses attached to this interface address,
1695  * either move them to another address on this interface, or save them until
1696  * such time as this interface is reconfigured for IPv6.
1697  */
1698 void
1699 in6_savemkludge(oia)
1700 	struct in6_ifaddr *oia;
1701 {
1702 	struct in6_ifaddr *ia;
1703 	struct in6_multi *in6m, *next;
1704 
1705 	IFP_TO_IA6(oia->ia_ifp, ia);
1706 	if (ia) {	/* there is another address */
1707 		for (in6m = oia->ia6_multiaddrs.lh_first; in6m; in6m = next){
1708 			next = in6m->in6m_entry.le_next;
1709 			IFAFREE(&in6m->in6m_ia->ia_ifa);
1710 			IFAREF(&ia->ia_ifa);
1711 			in6m->in6m_ia = ia;
1712 			LIST_INSERT_HEAD(&ia->ia6_multiaddrs, in6m, in6m_entry);
1713 		}
1714 	} else {	/* last address on this if deleted, save */
1715 		struct multi6_kludge *mk;
1716 
1717 		for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
1718 			if (mk->mk_ifp == oia->ia_ifp)
1719 				break;
1720 		}
1721 		if (mk == NULL) /* this should not happen! */
1722 			panic("in6_savemkludge: no kludge space");
1723 
1724 		for (in6m = oia->ia6_multiaddrs.lh_first; in6m; in6m = next){
1725 			next = in6m->in6m_entry.le_next;
1726 			IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
1727 			in6m->in6m_ia = NULL;
1728 			LIST_INSERT_HEAD(&mk->mk_head, in6m, in6m_entry);
1729 		}
1730 	}
1731 }
1732 
1733 /*
1734  * Continuation of multicast address hack:
1735  * If there was a multicast group list previously saved for this interface,
1736  * then we re-attach it to the first address configured on the i/f.
1737  */
1738 void
1739 in6_restoremkludge(ia, ifp)
1740 	struct in6_ifaddr *ia;
1741 	struct ifnet *ifp;
1742 {
1743 	struct multi6_kludge *mk;
1744 
1745 	for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
1746 		if (mk->mk_ifp == ifp) {
1747 			struct in6_multi *in6m, *next;
1748 
1749 			for (in6m = mk->mk_head.lh_first; in6m; in6m = next) {
1750 				next = in6m->in6m_entry.le_next;
1751 				in6m->in6m_ia = ia;
1752 				IFAREF(&ia->ia_ifa);
1753 				LIST_INSERT_HEAD(&ia->ia6_multiaddrs,
1754 				    in6m, in6m_entry);
1755 			}
1756 			LIST_INIT(&mk->mk_head);
1757 			break;
1758 		}
1759 	}
1760 }
1761 
1762 /*
1763  * Allocate space for the kludge at interface initialization time.
1764  * Formerly, we dynamically allocated the space in in6_savemkludge() with
1765  * malloc(M_WAITOK).  However, it was wrong since the function could be called
1766  * under an interrupt context (software timer on address lifetime expiration).
1767  * Also, we cannot just give up allocating the strucutre, since the group
1768  * membership structure is very complex and we need to keep it anyway.
1769  * Of course, this function MUST NOT be called under an interrupt context.
1770  * Specifically, it is expected to be called only from in6_ifattach(), though
1771  * it is a global function.
1772  */
1773 void
1774 in6_createmkludge(ifp)
1775 	struct ifnet *ifp;
1776 {
1777 	struct multi6_kludge *mk;
1778 
1779 	for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
1780 		/* If we've already had one, do not allocate. */
1781 		if (mk->mk_ifp == ifp)
1782 			return;
1783 	}
1784 
1785 	mk = malloc(sizeof(*mk), M_IPMADDR, M_WAITOK);
1786 
1787 	bzero(mk, sizeof(*mk));
1788 	LIST_INIT(&mk->mk_head);
1789 	mk->mk_ifp = ifp;
1790 	LIST_INSERT_HEAD(&in6_mk, mk, mk_entry);
1791 }
1792 
1793 void
1794 in6_purgemkludge(ifp)
1795 	struct ifnet *ifp;
1796 {
1797 	struct multi6_kludge *mk;
1798 	struct in6_multi *in6m;
1799 
1800 	for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
1801 		if (mk->mk_ifp != ifp)
1802 			continue;
1803 
1804 		/* leave from all multicast groups joined */
1805 		while ((in6m = LIST_FIRST(&mk->mk_head)) != NULL)
1806 			in6_delmulti(in6m);
1807 		LIST_REMOVE(mk, mk_entry);
1808 		free(mk, M_IPMADDR);
1809 		break;
1810 	}
1811 }
1812 
1813 /*
1814  * Add an address to the list of IP6 multicast addresses for a
1815  * given interface.
1816  */
1817 struct	in6_multi *
1818 in6_addmulti(maddr6, ifp, errorp)
1819 	struct in6_addr *maddr6;
1820 	struct ifnet *ifp;
1821 	int *errorp;
1822 {
1823 	struct	in6_ifaddr *ia;
1824 	struct	in6_ifreq ifr;
1825 	struct	in6_multi *in6m;
1826 	int	s = splsoftnet();
1827 
1828 	*errorp = 0;
1829 	/*
1830 	 * See if address already in list.
1831 	 */
1832 	IN6_LOOKUP_MULTI(*maddr6, ifp, in6m);
1833 	if (in6m != NULL) {
1834 		/*
1835 		 * Found it; just increment the refrence count.
1836 		 */
1837 		in6m->in6m_refcount++;
1838 	} else {
1839 		/*
1840 		 * New address; allocate a new multicast record
1841 		 * and link it into the interface's multicast list.
1842 		 */
1843 		in6m = (struct in6_multi *)
1844 			malloc(sizeof(*in6m), M_IPMADDR, M_NOWAIT);
1845 		if (in6m == NULL) {
1846 			splx(s);
1847 			*errorp = ENOBUFS;
1848 			return (NULL);
1849 		}
1850 		in6m->in6m_addr = *maddr6;
1851 		in6m->in6m_ifp = ifp;
1852 		in6m->in6m_refcount = 1;
1853 		IFP_TO_IA6(ifp, ia);
1854 		if (ia == NULL) {
1855 			free(in6m, M_IPMADDR);
1856 			splx(s);
1857 			*errorp = EADDRNOTAVAIL; /* appropriate? */
1858 			return (NULL);
1859 		}
1860 		in6m->in6m_ia = ia;
1861 		IFAREF(&ia->ia_ifa); /* gain a reference */
1862 		LIST_INSERT_HEAD(&ia->ia6_multiaddrs, in6m, in6m_entry);
1863 
1864 		/*
1865 		 * Ask the network driver to update its multicast reception
1866 		 * filter appropriately for the new address.
1867 		 */
1868 		bzero(&ifr.ifr_addr, sizeof(struct sockaddr_in6));
1869 		ifr.ifr_addr.sin6_len = sizeof(struct sockaddr_in6);
1870 		ifr.ifr_addr.sin6_family = AF_INET6;
1871 		ifr.ifr_addr.sin6_addr = *maddr6;
1872 		if (ifp->if_ioctl == NULL)
1873 			*errorp = ENXIO; /* XXX: appropriate? */
1874 		else
1875 			*errorp = (*ifp->if_ioctl)(ifp, SIOCADDMULTI,
1876 			    (caddr_t)&ifr);
1877 		if (*errorp) {
1878 			LIST_REMOVE(in6m, in6m_entry);
1879 			free(in6m, M_IPMADDR);
1880 			IFAFREE(&ia->ia_ifa);
1881 			splx(s);
1882 			return (NULL);
1883 		}
1884 		/*
1885 		 * Let MLD6 know that we have joined a new IP6 multicast
1886 		 * group.
1887 		 */
1888 		mld6_start_listening(in6m);
1889 	}
1890 	splx(s);
1891 	return (in6m);
1892 }
1893 
1894 /*
1895  * Delete a multicast address record.
1896  */
1897 void
1898 in6_delmulti(in6m)
1899 	struct in6_multi *in6m;
1900 {
1901 	struct	in6_ifreq ifr;
1902 	struct	in6_ifaddr *ia;
1903 	int	s = splsoftnet();
1904 
1905 	if (--in6m->in6m_refcount == 0) {
1906 		/*
1907 		 * No remaining claims to this record; let MLD6 know
1908 		 * that we are leaving the multicast group.
1909 		 */
1910 		mld6_stop_listening(in6m);
1911 
1912 		/*
1913 		 * Unlink from list.
1914 		 */
1915 		LIST_REMOVE(in6m, in6m_entry);
1916 		if (in6m->in6m_ia) {
1917 			IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
1918 		}
1919 		/*
1920 		 * Delete all references of this multicasting group from
1921 		 * the membership arrays
1922 		 */
1923 		for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1924 			struct in6_multi_mship *imm;
1925 			LIST_FOREACH(imm, &ia->ia6_memberships,
1926 			    i6mm_chain) {
1927 				if (imm->i6mm_maddr == in6m)
1928 					imm->i6mm_maddr = NULL;
1929 			}
1930 		}
1931 
1932 		/*
1933 		 * Notify the network driver to update its multicast
1934 		 * reception filter.
1935 		 */
1936 		bzero(&ifr.ifr_addr, sizeof(struct sockaddr_in6));
1937 		ifr.ifr_addr.sin6_len = sizeof(struct sockaddr_in6);
1938 		ifr.ifr_addr.sin6_family = AF_INET6;
1939 		ifr.ifr_addr.sin6_addr = in6m->in6m_addr;
1940 		(*in6m->in6m_ifp->if_ioctl)(in6m->in6m_ifp,
1941 					    SIOCDELMULTI, (caddr_t)&ifr);
1942 		free(in6m, M_IPMADDR);
1943 	}
1944 	splx(s);
1945 }
1946 
1947 struct in6_multi_mship *
1948 in6_joingroup(ifp, addr, errorp)
1949 	struct ifnet *ifp;
1950 	struct in6_addr *addr;
1951 	int *errorp;
1952 {
1953 	struct in6_multi_mship *imm;
1954 
1955 	imm = malloc(sizeof(*imm), M_IPMADDR, M_NOWAIT);
1956 	if (!imm) {
1957 		*errorp = ENOBUFS;
1958 		return NULL;
1959 	}
1960 	imm->i6mm_maddr = in6_addmulti(addr, ifp, errorp);
1961 	if (!imm->i6mm_maddr) {
1962 		/* *errorp is alrady set */
1963 		free(imm, M_IPMADDR);
1964 		return NULL;
1965 	}
1966 	return imm;
1967 }
1968 
1969 int
1970 in6_leavegroup(imm)
1971 	struct in6_multi_mship *imm;
1972 {
1973 
1974 	if (imm->i6mm_maddr)
1975 		in6_delmulti(imm->i6mm_maddr);
1976 	free(imm,  M_IPMADDR);
1977 	return 0;
1978 }
1979 
1980 /*
1981  * Find an IPv6 interface link-local address specific to an interface.
1982  */
1983 struct in6_ifaddr *
1984 in6ifa_ifpforlinklocal(ifp, ignoreflags)
1985 	struct ifnet *ifp;
1986 	int ignoreflags;
1987 {
1988 	struct ifaddr *ifa;
1989 
1990 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
1991 	{
1992 		if (ifa->ifa_addr == NULL)
1993 			continue;	/* just for safety */
1994 		if (ifa->ifa_addr->sa_family != AF_INET6)
1995 			continue;
1996 		if (IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa))) {
1997 			if ((((struct in6_ifaddr *)ifa)->ia6_flags &
1998 			     ignoreflags) != 0)
1999 				continue;
2000 			break;
2001 		}
2002 	}
2003 
2004 	return ((struct in6_ifaddr *)ifa);
2005 }
2006 
2007 
2008 /*
2009  * find the internet address corresponding to a given interface and address.
2010  */
2011 struct in6_ifaddr *
2012 in6ifa_ifpwithaddr(ifp, addr)
2013 	struct ifnet *ifp;
2014 	struct in6_addr *addr;
2015 {
2016 	struct ifaddr *ifa;
2017 
2018 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
2019 	{
2020 		if (ifa->ifa_addr == NULL)
2021 			continue;	/* just for safety */
2022 		if (ifa->ifa_addr->sa_family != AF_INET6)
2023 			continue;
2024 		if (IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa)))
2025 			break;
2026 	}
2027 
2028 	return ((struct in6_ifaddr *)ifa);
2029 }
2030 
2031 /*
2032  * Convert IP6 address to printable (loggable) representation.
2033  */
2034 static int ip6round = 0;
2035 char *
2036 ip6_sprintf(addr)
2037 	const struct in6_addr *addr;
2038 {
2039 	static char ip6buf[8][48];
2040 	int i;
2041 	char *cp;
2042 	const u_int16_t *a = (const u_int16_t *)addr;
2043 	const u_int8_t *d;
2044 	int dcolon = 0;
2045 
2046 	ip6round = (ip6round + 1) & 7;
2047 	cp = ip6buf[ip6round];
2048 
2049 	for (i = 0; i < 8; i++) {
2050 		if (dcolon == 1) {
2051 			if (*a == 0) {
2052 				if (i == 7)
2053 					*cp++ = ':';
2054 				a++;
2055 				continue;
2056 			} else
2057 				dcolon = 2;
2058 		}
2059 		if (*a == 0) {
2060 			if (dcolon == 0 && *(a + 1) == 0) {
2061 				if (i == 0)
2062 					*cp++ = ':';
2063 				*cp++ = ':';
2064 				dcolon = 1;
2065 			} else {
2066 				*cp++ = '0';
2067 				*cp++ = ':';
2068 			}
2069 			a++;
2070 			continue;
2071 		}
2072 		d = (const u_char *)a;
2073 		*cp++ = hexdigits[*d >> 4];
2074 		*cp++ = hexdigits[*d++ & 0xf];
2075 		*cp++ = hexdigits[*d >> 4];
2076 		*cp++ = hexdigits[*d & 0xf];
2077 		*cp++ = ':';
2078 		a++;
2079 	}
2080 	*--cp = 0;
2081 	return (ip6buf[ip6round]);
2082 }
2083 
2084 /*
2085  * Determine if an address is on a local network.
2086  */
2087 int
2088 in6_localaddr(in6)
2089 	struct in6_addr *in6;
2090 {
2091 	struct in6_ifaddr *ia;
2092 
2093 	if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6))
2094 		return (1);
2095 
2096 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
2097 		if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
2098 					      &ia->ia_prefixmask.sin6_addr))
2099 			return (1);
2100 
2101 	return (0);
2102 }
2103 
2104 int
2105 in6_is_addr_deprecated(sa6)
2106 	struct sockaddr_in6 *sa6;
2107 {
2108 	struct in6_ifaddr *ia;
2109 
2110 	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
2111 		if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
2112 		    &sa6->sin6_addr) &&
2113 #ifdef SCOPEDROUTING
2114 		    ia->ia_addr.sin6_scope_id == sa6->sin6_scope_id &&
2115 #endif
2116 		    (ia->ia6_flags & IN6_IFF_DEPRECATED) != 0)
2117 			return (1); /* true */
2118 
2119 		/* XXX: do we still have to go thru the rest of the list? */
2120 	}
2121 
2122 	return (0);		/* false */
2123 }
2124 
2125 /*
2126  * return length of part which dst and src are equal
2127  * hard coding...
2128  */
2129 int
2130 in6_matchlen(src, dst)
2131 struct in6_addr *src, *dst;
2132 {
2133 	int match = 0;
2134 	u_char *s = (u_char *)src, *d = (u_char *)dst;
2135 	u_char *lim = s + 16, r;
2136 
2137 	while (s < lim)
2138 		if ((r = (*d++ ^ *s++)) != 0) {
2139 			while (r < 128) {
2140 				match++;
2141 				r <<= 1;
2142 			}
2143 			break;
2144 		} else
2145 			match += 8;
2146 	return match;
2147 }
2148 
2149 /* XXX: to be scope conscious */
2150 int
2151 in6_are_prefix_equal(p1, p2, len)
2152 	struct in6_addr *p1, *p2;
2153 	int len;
2154 {
2155 	int bytelen, bitlen;
2156 
2157 	/* sanity check */
2158 	if (0 > len || len > 128) {
2159 		log(LOG_ERR, "in6_are_prefix_equal: invalid prefix length(%d)\n",
2160 		    len);
2161 		return (0);
2162 	}
2163 
2164 	bytelen = len / 8;
2165 	bitlen = len % 8;
2166 
2167 	if (bcmp(&p1->s6_addr, &p2->s6_addr, bytelen))
2168 		return (0);
2169 	if (bitlen != 0 &&
2170 	    p1->s6_addr[bytelen] >> (8 - bitlen) !=
2171 	    p2->s6_addr[bytelen] >> (8 - bitlen))
2172 		return (0);
2173 
2174 	return (1);
2175 }
2176 
2177 void
2178 in6_prefixlen2mask(maskp, len)
2179 	struct in6_addr *maskp;
2180 	int len;
2181 {
2182 	static const u_char maskarray[8] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
2183 	int bytelen, bitlen, i;
2184 
2185 	/* sanity check */
2186 	if (0 > len || len > 128) {
2187 		log(LOG_ERR, "in6_prefixlen2mask: invalid prefix length(%d)\n",
2188 		    len);
2189 		return;
2190 	}
2191 
2192 	bzero(maskp, sizeof(*maskp));
2193 	bytelen = len / 8;
2194 	bitlen = len % 8;
2195 	for (i = 0; i < bytelen; i++)
2196 		maskp->s6_addr[i] = 0xff;
2197 	if (bitlen)
2198 		maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
2199 }
2200 
2201 /*
2202  * return the best address out of the same scope. if no address was
2203  * found, return the first valid address from designated IF.
2204  */
2205 struct in6_ifaddr *
2206 in6_ifawithifp(ifp, dst)
2207 	struct ifnet *ifp;
2208 	struct in6_addr *dst;
2209 {
2210 	int dst_scope =	in6_addrscope(dst), blen = -1, tlen;
2211 	struct ifaddr *ifa;
2212 	struct in6_ifaddr *besta = 0;
2213 	struct in6_ifaddr *dep[2];	/* last-resort: deprecated */
2214 
2215 	dep[0] = dep[1] = NULL;
2216 
2217 	/*
2218 	 * We first look for addresses in the same scope.
2219 	 * If there is one, return it.
2220 	 * If two or more, return one which matches the dst longest.
2221 	 * If none, return one of global addresses assigned other ifs.
2222 	 */
2223 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
2224 	{
2225 		if (ifa->ifa_addr->sa_family != AF_INET6)
2226 			continue;
2227 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)
2228 			continue; /* XXX: is there any case to allow anycast? */
2229 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY)
2230 			continue; /* don't use this interface */
2231 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DETACHED)
2232 			continue;
2233 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
2234 			if (ip6_use_deprecated)
2235 				dep[0] = (struct in6_ifaddr *)ifa;
2236 			continue;
2237 		}
2238 
2239 		if (dst_scope == in6_addrscope(IFA_IN6(ifa))) {
2240 			/*
2241 			 * call in6_matchlen() as few as possible
2242 			 */
2243 			if (besta) {
2244 				if (blen == -1)
2245 					blen = in6_matchlen(&besta->ia_addr.sin6_addr, dst);
2246 				tlen = in6_matchlen(IFA_IN6(ifa), dst);
2247 				if (tlen > blen) {
2248 					blen = tlen;
2249 					besta = (struct in6_ifaddr *)ifa;
2250 				}
2251 			} else
2252 				besta = (struct in6_ifaddr *)ifa;
2253 		}
2254 	}
2255 	if (besta)
2256 		return (besta);
2257 
2258 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
2259 	{
2260 		if (ifa->ifa_addr->sa_family != AF_INET6)
2261 			continue;
2262 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)
2263 			continue; /* XXX: is there any case to allow anycast? */
2264 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY)
2265 			continue; /* don't use this interface */
2266 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DETACHED)
2267 			continue;
2268 		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
2269 			if (ip6_use_deprecated)
2270 				dep[1] = (struct in6_ifaddr *)ifa;
2271 			continue;
2272 		}
2273 
2274 		return (struct in6_ifaddr *)ifa;
2275 	}
2276 
2277 	/* use the last-resort values, that are, deprecated addresses */
2278 	if (dep[0])
2279 		return dep[0];
2280 	if (dep[1])
2281 		return dep[1];
2282 
2283 	return NULL;
2284 }
2285 
2286 /*
2287  * perform DAD when interface becomes IFF_UP.
2288  */
2289 void
2290 in6_if_up(ifp)
2291 	struct ifnet *ifp;
2292 {
2293 	struct ifaddr *ifa;
2294 	struct in6_ifaddr *ia;
2295 	int dad_delay;		/* delay ticks before DAD output */
2296 
2297 	/*
2298 	 * special cases, like 6to4, are handled in in6_ifattach
2299 	 */
2300 	in6_ifattach(ifp, NULL);
2301 
2302 	dad_delay = 0;
2303 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
2304 	{
2305 		if (ifa->ifa_addr->sa_family != AF_INET6)
2306 			continue;
2307 		ia = (struct in6_ifaddr *)ifa;
2308 		if (ia->ia6_flags & IN6_IFF_TENTATIVE)
2309 			nd6_dad_start(ifa, &dad_delay);
2310 	}
2311 }
2312 
2313 int
2314 in6if_do_dad(ifp)
2315 	struct ifnet *ifp;
2316 {
2317 	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2318 		return (0);
2319 
2320 	switch (ifp->if_type) {
2321 	case IFT_FAITH:
2322 		/*
2323 		 * These interfaces do not have the IFF_LOOPBACK flag,
2324 		 * but loop packets back.  We do not have to do DAD on such
2325 		 * interfaces.  We should even omit it, because loop-backed
2326 		 * NS would confuse the DAD procedure.
2327 		 */
2328 		return (0);
2329 	default:
2330 		/*
2331 		 * Our DAD routine requires the interface up and running.
2332 		 * However, some interfaces can be up before the RUNNING
2333 		 * status.  Additionaly, users may try to assign addresses
2334 		 * before the interface becomes up (or running).
2335 		 * We simply skip DAD in such a case as a work around.
2336 		 * XXX: we should rather mark "tentative" on such addresses,
2337 		 * and do DAD after the interface becomes ready.
2338 		 */
2339 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
2340 		    (IFF_UP|IFF_RUNNING))
2341 			return (0);
2342 
2343 		return (1);
2344 	}
2345 }
2346 
2347 /*
2348  * Calculate max IPv6 MTU through all the interfaces and store it
2349  * to in6_maxmtu.
2350  */
2351 void
2352 in6_setmaxmtu()
2353 {
2354 	unsigned long maxmtu = 0;
2355 	struct ifnet *ifp;
2356 
2357 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
2358 	{
2359 		/* this function can be called during ifnet initialization */
2360 		if (!ifp->if_afdata[AF_INET6])
2361 			continue;
2362 		if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
2363 		    IN6_LINKMTU(ifp) > maxmtu)
2364 			maxmtu = IN6_LINKMTU(ifp);
2365 	}
2366 	if (maxmtu)	     /* update only when maxmtu is positive */
2367 		in6_maxmtu = maxmtu;
2368 }
2369 
2370 void *
2371 in6_domifattach(ifp)
2372 	struct ifnet *ifp;
2373 {
2374 	struct in6_ifextra *ext;
2375 
2376 	ext = (struct in6_ifextra *)malloc(sizeof(*ext), M_IFADDR, M_WAITOK);
2377 	bzero(ext, sizeof(*ext));
2378 
2379 	ext->in6_ifstat = (struct in6_ifstat *)malloc(sizeof(struct in6_ifstat),
2380 	    M_IFADDR, M_WAITOK);
2381 	bzero(ext->in6_ifstat, sizeof(*ext->in6_ifstat));
2382 
2383 	ext->icmp6_ifstat =
2384 	    (struct icmp6_ifstat *)malloc(sizeof(struct icmp6_ifstat),
2385 	    M_IFADDR, M_WAITOK);
2386 	bzero(ext->icmp6_ifstat, sizeof(*ext->icmp6_ifstat));
2387 
2388 	ext->nd_ifinfo = nd6_ifattach(ifp);
2389 	ext->scope6_id = scope6_ifattach(ifp);
2390 	return ext;
2391 }
2392 
2393 void
2394 in6_domifdetach(ifp, aux)
2395 	struct ifnet *ifp;
2396 	void *aux;
2397 {
2398 	struct in6_ifextra *ext = (struct in6_ifextra *)aux;
2399 
2400 	nd6_ifdetach(ext->nd_ifinfo);
2401 	free(ext->in6_ifstat, M_IFADDR);
2402 	free(ext->icmp6_ifstat, M_IFADDR);
2403 	scope6_ifdetach(ext->scope6_id);
2404 	free(ext, M_IFADDR);
2405 }
2406