xref: /dragonfly/sys/netinet6/nd6.c (revision be09fc23)
1 /*	$FreeBSD: src/sys/netinet6/nd6.c,v 1.2.2.15 2003/05/06 06:46:58 suz Exp $	*/
2 /*	$KAME: nd6.c,v 1.144 2001/05/24 07:44:00 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  * XXX
35  * KAME 970409 note:
36  * BSD/OS version heavily modifies this code, related to llinfo.
37  * Since we don't have BSD/OS version of net/route.c in our hand,
38  * I left the code mostly as it was in 970310.  -- itojun
39  */
40 
41 #include "opt_inet.h"
42 #include "opt_inet6.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/callout.h>
47 #include <sys/malloc.h>
48 #include <sys/mbuf.h>
49 #include <sys/socket.h>
50 #include <sys/sockio.h>
51 #include <sys/time.h>
52 #include <sys/kernel.h>
53 #include <sys/protosw.h>
54 #include <sys/errno.h>
55 #include <sys/syslog.h>
56 #include <sys/queue.h>
57 #include <sys/sysctl.h>
58 #include <sys/mutex.h>
59 
60 #include <sys/thread2.h>
61 #include <sys/mutex2.h>
62 
63 #include <net/if.h>
64 #include <net/if_dl.h>
65 #include <net/if_types.h>
66 #include <net/route.h>
67 #include <net/netisr2.h>
68 #include <net/netmsg2.h>
69 
70 #include <netinet/in.h>
71 #include <netinet/if_ether.h>
72 #include <netinet6/in6_var.h>
73 #include <netinet/ip6.h>
74 #include <netinet6/ip6_var.h>
75 #include <netinet6/nd6.h>
76 #include <netinet/icmp6.h>
77 
78 #include <net/net_osdep.h>
79 
80 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
81 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
82 
83 #define SIN6(s) ((struct sockaddr_in6 *)s)
84 #define SDL(s) ((struct sockaddr_dl *)s)
85 
86 /* timer values */
87 int	nd6_prune	= 1;	/* walk list every 1 seconds */
88 int	nd6_delay	= 5;	/* delay first probe time 5 second */
89 int	nd6_umaxtries	= 3;	/* maximum unicast query */
90 int	nd6_mmaxtries	= 3;	/* maximum multicast query */
91 int	nd6_useloopback = 1;	/* use loopback interface for local traffic */
92 int	nd6_gctimer	= (60 * 60 * 24); /* 1 day: garbage collection timer */
93 
94 /* preventing too many loops in ND option parsing */
95 int nd6_maxndopt = 10;	/* max # of ND options allowed */
96 
97 int nd6_maxnudhint = 0;	/* max # of subsequent upper layer hints */
98 
99 #ifdef ND6_DEBUG
100 int nd6_debug = 1;
101 #else
102 int nd6_debug = 0;
103 #endif
104 
105 /* for debugging? */
106 static int nd6_inuse, nd6_allocated;
107 
108 struct llinfo_nd6 llinfo_nd6 = {&llinfo_nd6, &llinfo_nd6};
109 struct nd_drhead nd_defrouter;
110 struct nd_prhead nd_prefix = { 0 };
111 struct mtx nd6_mtx = MTX_INITIALIZER("nd6");
112 
113 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL;
114 static struct sockaddr_in6 all1_sa;
115 
116 static void nd6_setmtu0 (struct ifnet *, struct nd_ifinfo *);
117 static int regen_tmpaddr (struct in6_ifaddr *);
118 static void nd6_slowtimo(void *);
119 static void nd6_slowtimo_dispatch(netmsg_t);
120 static void nd6_timer(void *);
121 static void nd6_timer_dispatch(netmsg_t);
122 
123 static struct callout nd6_slowtimo_ch;
124 static struct netmsg_base nd6_slowtimo_netmsg;
125 
126 static struct callout nd6_timer_ch;
127 static struct netmsg_base nd6_timer_netmsg;
128 
129 void
130 nd6_init(void)
131 {
132 	static int nd6_init_done = 0;
133 	int i;
134 
135 	if (nd6_init_done) {
136 		log(LOG_NOTICE, "nd6_init called more than once(ignored)\n");
137 		return;
138 	}
139 
140 	all1_sa.sin6_family = AF_INET6;
141 	all1_sa.sin6_len = sizeof(struct sockaddr_in6);
142 	for (i = 0; i < sizeof(all1_sa.sin6_addr); i++)
143 		all1_sa.sin6_addr.s6_addr[i] = 0xff;
144 
145 	/* initialization of the default router list */
146 	TAILQ_INIT(&nd_defrouter);
147 
148 	nd6_init_done = 1;
149 
150 	/* start timer */
151 	callout_init_mp(&nd6_slowtimo_ch);
152 	netmsg_init(&nd6_slowtimo_netmsg, NULL, &netisr_adone_rport,
153 	    MSGF_PRIORITY, nd6_slowtimo_dispatch);
154 	callout_reset_bycpu(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
155 	    nd6_slowtimo, NULL, 0);
156 }
157 
158 struct nd_ifinfo *
159 nd6_ifattach(struct ifnet *ifp)
160 {
161 	struct nd_ifinfo *nd;
162 
163 	nd = (struct nd_ifinfo *)kmalloc(sizeof(*nd), M_IP6NDP,
164 	    M_WAITOK | M_ZERO);
165 
166 	nd->initialized = 1;
167 
168 	nd->linkmtu = ifp->if_mtu;
169 	nd->chlim = IPV6_DEFHLIM;
170 	nd->basereachable = REACHABLE_TIME;
171 	nd->reachable = ND_COMPUTE_RTIME(nd->basereachable);
172 	nd->retrans = RETRANS_TIMER;
173 	nd->receivedra = 0;
174 
175 	/*
176 	 * Note that the default value of ip6_accept_rtadv is 0, which means
177 	 * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV
178 	 * here.
179 	 */
180 	nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV);
181 
182 	/* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
183 	nd6_setmtu0(ifp, nd);
184 	return nd;
185 }
186 
187 void
188 nd6_ifdetach(struct nd_ifinfo *nd)
189 {
190 	kfree(nd, M_IP6NDP);
191 }
192 
193 /*
194  * Reset ND level link MTU. This function is called when the physical MTU
195  * changes, which means we might have to adjust the ND level MTU.
196  */
197 void
198 nd6_setmtu(struct ifnet *ifp)
199 {
200 	nd6_setmtu0(ifp, ND_IFINFO(ifp));
201 }
202 
203 struct netmsg_nd6setmtu {
204 	struct netmsg_base	nmsg;
205 	struct ifnet		*ifp;
206 	struct nd_ifinfo	*ndi;
207 };
208 
209 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
210 static void
211 nd6_setmtu0_dispatch(netmsg_t msg)
212 {
213 	struct netmsg_nd6setmtu *nmsg = (struct netmsg_nd6setmtu *)msg;
214 	struct ifnet *ifp = nmsg->ifp;
215 	struct nd_ifinfo *ndi = nmsg->ndi;
216 	u_long oldmaxmtu;
217 	u_long oldlinkmtu;
218 
219 	oldmaxmtu = ndi->maxmtu;
220 	oldlinkmtu = ndi->linkmtu;
221 
222 	switch (ifp->if_type) {
223 	case IFT_ETHER:
224 		ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
225 		break;
226 	case IFT_IEEE1394:	/* XXX should be IEEE1394MTU(1500) */
227 		ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
228 		break;
229 #ifdef IFT_IEEE80211
230 	case IFT_IEEE80211:	/* XXX should be IEEE80211MTU(1500) */
231 		ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
232 		break;
233 #endif
234 	default:
235 		ndi->maxmtu = ifp->if_mtu;
236 		break;
237 	}
238 
239 	if (oldmaxmtu != ndi->maxmtu) {
240 		/*
241 		 * If the ND level MTU is not set yet, or if the maxmtu
242 		 * is reset to a smaller value than the ND level MTU,
243 		 * also reset the ND level MTU.
244 		 */
245 		if (ndi->linkmtu == 0 ||
246 		    ndi->maxmtu < ndi->linkmtu) {
247 			ndi->linkmtu = ndi->maxmtu;
248 			/* also adjust in6_maxmtu if necessary. */
249 			if (oldlinkmtu == 0) {
250 				/*
251 				 * XXX: the case analysis is grotty, but
252 				 * it is not efficient to call in6_setmaxmtu()
253 				 * here when we are during the initialization
254 				 * procedure.
255 				 */
256 				if (in6_maxmtu < ndi->linkmtu)
257 					in6_maxmtu = ndi->linkmtu;
258 			} else
259 				in6_setmaxmtu();
260 		}
261 	}
262 #undef MIN
263 
264 	lwkt_replymsg(&nmsg->nmsg.lmsg, 0);
265 }
266 
267 void
268 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi)
269 {
270 	struct netmsg_nd6setmtu nmsg;
271 
272 	netmsg_init(&nmsg.nmsg, NULL, &curthread->td_msgport, 0,
273 	    nd6_setmtu0_dispatch);
274 	nmsg.ifp = ifp;
275 	nmsg.ndi = ndi;
276 	lwkt_domsg(netisr_cpuport(0), &nmsg.nmsg.lmsg, 0);
277 }
278 
279 void
280 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
281 {
282 	bzero(ndopts, sizeof(*ndopts));
283 	ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
284 	ndopts->nd_opts_last
285 		= (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
286 
287 	if (icmp6len == 0) {
288 		ndopts->nd_opts_done = 1;
289 		ndopts->nd_opts_search = NULL;
290 	}
291 }
292 
293 /*
294  * Take one ND option.
295  */
296 struct nd_opt_hdr *
297 nd6_option(union nd_opts *ndopts)
298 {
299 	struct nd_opt_hdr *nd_opt;
300 	int olen;
301 
302 	if (!ndopts)
303 		panic("ndopts == NULL in nd6_option");
304 	if (!ndopts->nd_opts_last)
305 		panic("uninitialized ndopts in nd6_option");
306 	if (!ndopts->nd_opts_search)
307 		return NULL;
308 	if (ndopts->nd_opts_done)
309 		return NULL;
310 
311 	nd_opt = ndopts->nd_opts_search;
312 
313 	/* make sure nd_opt_len is inside the buffer */
314 	if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) {
315 		bzero(ndopts, sizeof(*ndopts));
316 		return NULL;
317 	}
318 
319 	olen = nd_opt->nd_opt_len << 3;
320 	if (olen == 0) {
321 		/*
322 		 * Message validation requires that all included
323 		 * options have a length that is greater than zero.
324 		 */
325 		bzero(ndopts, sizeof(*ndopts));
326 		return NULL;
327 	}
328 
329 	ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen);
330 	if (ndopts->nd_opts_search > ndopts->nd_opts_last) {
331 		/* option overruns the end of buffer, invalid */
332 		bzero(ndopts, sizeof(*ndopts));
333 		return NULL;
334 	} else if (ndopts->nd_opts_search == ndopts->nd_opts_last) {
335 		/* reached the end of options chain */
336 		ndopts->nd_opts_done = 1;
337 		ndopts->nd_opts_search = NULL;
338 	}
339 	return nd_opt;
340 }
341 
342 /*
343  * Parse multiple ND options.
344  * This function is much easier to use, for ND routines that do not need
345  * multiple options of the same type.
346  */
347 int
348 nd6_options(union nd_opts *ndopts)
349 {
350 	struct nd_opt_hdr *nd_opt;
351 	int i = 0;
352 
353 	if (!ndopts)
354 		panic("ndopts == NULL in nd6_options");
355 	if (!ndopts->nd_opts_last)
356 		panic("uninitialized ndopts in nd6_options");
357 	if (!ndopts->nd_opts_search)
358 		return 0;
359 
360 	while (1) {
361 		nd_opt = nd6_option(ndopts);
362 		if (!nd_opt && !ndopts->nd_opts_last) {
363 			/*
364 			 * Message validation requires that all included
365 			 * options have a length that is greater than zero.
366 			 */
367 			icmp6stat.icp6s_nd_badopt++;
368 			bzero(ndopts, sizeof(*ndopts));
369 			return -1;
370 		}
371 
372 		if (!nd_opt)
373 			goto skip1;
374 
375 		switch (nd_opt->nd_opt_type) {
376 		case ND_OPT_SOURCE_LINKADDR:
377 		case ND_OPT_TARGET_LINKADDR:
378 		case ND_OPT_MTU:
379 		case ND_OPT_REDIRECTED_HEADER:
380 			if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
381 				nd6log((LOG_INFO,
382 				    "duplicated ND6 option found (type=%d)\n",
383 				    nd_opt->nd_opt_type));
384 				/* XXX bark? */
385 			} else {
386 				ndopts->nd_opt_array[nd_opt->nd_opt_type]
387 					= nd_opt;
388 			}
389 			break;
390 		case ND_OPT_PREFIX_INFORMATION:
391 			if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) {
392 				ndopts->nd_opt_array[nd_opt->nd_opt_type]
393 					= nd_opt;
394 			}
395 			ndopts->nd_opts_pi_end =
396 				(struct nd_opt_prefix_info *)nd_opt;
397 			break;
398 		default:
399 			/*
400 			 * Unknown options must be silently ignored,
401 			 * to accomodate future extension to the protocol.
402 			 */
403 			nd6log((LOG_DEBUG,
404 			    "nd6_options: unsupported option %d - "
405 			    "option ignored\n", nd_opt->nd_opt_type));
406 		}
407 
408 skip1:
409 		i++;
410 		if (i > nd6_maxndopt) {
411 			icmp6stat.icp6s_nd_toomanyopt++;
412 			nd6log((LOG_INFO, "too many loop in nd opt\n"));
413 			break;
414 		}
415 
416 		if (ndopts->nd_opts_done)
417 			break;
418 	}
419 
420 	return 0;
421 }
422 
423 /*
424  * ND6 timer routine to expire default route list and prefix list
425  */
426 static void
427 nd6_timer_dispatch(netmsg_t nmsg)
428 {
429 	struct llinfo_nd6 *ln;
430 	struct nd_defrouter *dr;
431 	struct nd_prefix *pr;
432 	struct ifnet *ifp;
433 	struct in6_ifaddr *ia6, *nia6;
434 
435 	ASSERT_IN_NETISR(0);
436 
437 	crit_enter();
438 	lwkt_replymsg(&nmsg->lmsg, 0);	/* reply ASAP */
439 	crit_exit();
440 
441 	mtx_lock(&nd6_mtx);
442 
443 	ln = llinfo_nd6.ln_next;
444 	while (ln && ln != &llinfo_nd6) {
445 		struct rtentry *rt;
446 		struct sockaddr_in6 *dst;
447 		struct llinfo_nd6 *next = ln->ln_next;
448 		/* XXX: used for the DELAY case only: */
449 		struct nd_ifinfo *ndi = NULL;
450 
451 		if ((rt = ln->ln_rt) == NULL) {
452 			ln = next;
453 			continue;
454 		}
455 		if ((ifp = rt->rt_ifp) == NULL) {
456 			ln = next;
457 			continue;
458 		}
459 		ndi = ND_IFINFO(ifp);
460 		dst = (struct sockaddr_in6 *)rt_key(rt);
461 
462 		if (ln->ln_expire > time_uptime) {
463 			ln = next;
464 			continue;
465 		}
466 
467 		/* sanity check */
468 		if (!rt)
469 			panic("rt=0 in nd6_timer(ln=%p)", ln);
470 		if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln)
471 			panic("rt_llinfo(%p) is not equal to ln(%p)",
472 			      rt->rt_llinfo, ln);
473 		if (!dst)
474 			panic("dst=0 in nd6_timer(ln=%p)", ln);
475 
476 		switch (ln->ln_state) {
477 		case ND6_LLINFO_INCOMPLETE:
478 			if (ln->ln_asked < nd6_mmaxtries) {
479 				ln->ln_asked++;
480 				ln->ln_expire = time_uptime +
481 					ND_IFINFO(ifp)->retrans / 1000;
482 				nd6_ns_output(ifp, NULL, &dst->sin6_addr,
483 					ln, 0);
484 			} else {
485 				struct mbuf *m = ln->ln_hold;
486 				if (m) {
487 					if (rt->rt_ifp) {
488 						/*
489 						 * Fake rcvif to make ICMP error
490 						 * more helpful in diagnosing
491 						 * for the receiver.
492 						 * XXX: should we consider
493 						 * older rcvif?
494 						 */
495 						m->m_pkthdr.rcvif = rt->rt_ifp;
496 					}
497 					icmp6_error(m, ICMP6_DST_UNREACH,
498 						    ICMP6_DST_UNREACH_ADDR, 0);
499 					ln->ln_hold = NULL;
500 				}
501 				next = nd6_free(rt);
502 			}
503 			break;
504 		case ND6_LLINFO_REACHABLE:
505 			if (ln->ln_expire) {
506 				ln->ln_state = ND6_LLINFO_STALE;
507 				ln->ln_expire = time_uptime + nd6_gctimer;
508 			}
509 			break;
510 
511 		case ND6_LLINFO_STALE:
512 			/* Garbage Collection(RFC 2461 5.3) */
513 			if (ln->ln_expire)
514 				next = nd6_free(rt);
515 			break;
516 
517 		case ND6_LLINFO_DELAY:
518 			if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD)) {
519 				/* We need NUD */
520 				ln->ln_asked = 1;
521 				ln->ln_state = ND6_LLINFO_PROBE;
522 				ln->ln_expire = time_uptime +
523 					ndi->retrans / 1000;
524 				nd6_ns_output(ifp, &dst->sin6_addr,
525 					      &dst->sin6_addr,
526 					      ln, 0);
527 			} else {
528 				ln->ln_state = ND6_LLINFO_STALE; /* XXX */
529 				ln->ln_expire = time_uptime + nd6_gctimer;
530 			}
531 			break;
532 		case ND6_LLINFO_PROBE:
533 			if (ln->ln_asked < nd6_umaxtries) {
534 				ln->ln_asked++;
535 				ln->ln_expire = time_uptime +
536 					ND_IFINFO(ifp)->retrans / 1000;
537 				nd6_ns_output(ifp, &dst->sin6_addr,
538 					       &dst->sin6_addr, ln, 0);
539 			} else {
540 				next = nd6_free(rt);
541 			}
542 			break;
543 		}
544 		ln = next;
545 	}
546 
547 	/* expire default router list */
548 	dr = TAILQ_FIRST(&nd_defrouter);
549 	while (dr) {
550 		if (dr->expire && dr->expire < time_uptime) {
551 			struct nd_defrouter *t;
552 			t = TAILQ_NEXT(dr, dr_entry);
553 			defrtrlist_del(dr);
554 			dr = t;
555 		} else {
556 			dr = TAILQ_NEXT(dr, dr_entry);
557 		}
558 	}
559 
560 	/*
561 	 * expire interface addresses.
562 	 * in the past the loop was inside prefix expiry processing.
563 	 * However, from a stricter speci-confrmance standpoint, we should
564 	 * rather separate address lifetimes and prefix lifetimes.
565 	 */
566 addrloop:
567 	for (ia6 = in6_ifaddr; ia6; ia6 = nia6) {
568 		nia6 = ia6->ia_next;
569 		/* check address lifetime */
570 		if (IFA6_IS_INVALID(ia6)) {
571 			int regen = 0;
572 
573 			/*
574 			 * If the expiring address is temporary, try
575 			 * regenerating a new one.  This would be useful when
576 			 * we suspended a laptop PC, then turned it on after a
577 			 * period that could invalidate all temporary
578 			 * addresses.  Although we may have to restart the
579 			 * loop (see below), it must be after purging the
580 			 * address.  Otherwise, we'd see an infinite loop of
581 			 * regeneration.
582 			 */
583 			if (ip6_use_tempaddr &&
584 			    (ia6->ia6_flags & IN6_IFF_TEMPORARY)) {
585 				if (regen_tmpaddr(ia6) == 0)
586 					regen = 1;
587 			}
588 
589 			in6_purgeaddr(&ia6->ia_ifa);
590 
591 			if (regen)
592 				goto addrloop; /* XXX: see below */
593 		}
594 		if (IFA6_IS_DEPRECATED(ia6)) {
595 			int oldflags = ia6->ia6_flags;
596 
597 			ia6->ia6_flags |= IN6_IFF_DEPRECATED;
598 
599 			/*
600 			 * If a temporary address has just become deprecated,
601 			 * regenerate a new one if possible.
602 			 */
603 			if (ip6_use_tempaddr &&
604 			    (ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
605 			    !(oldflags & IN6_IFF_DEPRECATED)) {
606 
607 				if (regen_tmpaddr(ia6) == 0) {
608 					/*
609 					 * A new temporary address is
610 					 * generated.
611 					 * XXX: this means the address chain
612 					 * has changed while we are still in
613 					 * the loop.  Although the change
614 					 * would not cause disaster (because
615 					 * it's not a deletion, but an
616 					 * addition,) we'd rather restart the
617 					 * loop just for safety.  Or does this
618 					 * significantly reduce performance??
619 					 */
620 					goto addrloop;
621 				}
622 			}
623 		} else {
624 			/*
625 			 * A new RA might have made a deprecated address
626 			 * preferred.
627 			 */
628 			ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
629 		}
630 	}
631 
632 	/* expire prefix list */
633 	pr = nd_prefix.lh_first;
634 	while (pr) {
635 		/*
636 		 * check prefix lifetime.
637 		 * since pltime is just for autoconf, pltime processing for
638 		 * prefix is not necessary.
639 		 */
640 		if (pr->ndpr_expire && pr->ndpr_expire < time_uptime) {
641 			struct nd_prefix *t;
642 			t = pr->ndpr_next;
643 
644 			/*
645 			 * address expiration and prefix expiration are
646 			 * separate.  NEVER perform in6_purgeaddr here.
647 			 */
648 
649 			prelist_remove(pr);
650 			pr = t;
651 		} else
652 			pr = pr->ndpr_next;
653 	}
654 
655 	mtx_unlock(&nd6_mtx);
656 
657 	callout_reset(&nd6_timer_ch, nd6_prune * hz, nd6_timer, NULL);
658 }
659 
660 static void
661 nd6_timer(void *arg __unused)
662 {
663 	struct lwkt_msg *lmsg = &nd6_timer_netmsg.lmsg;
664 
665 	KASSERT(mycpuid == 0, ("not on cpu0"));
666 	crit_enter();
667 	if (lmsg->ms_flags & MSGF_DONE)
668 		lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg);
669 	crit_exit();
670 }
671 
672 void
673 nd6_timer_init(void)
674 {
675 	callout_init_mp(&nd6_timer_ch);
676 	netmsg_init(&nd6_timer_netmsg, NULL, &netisr_adone_rport,
677 	    MSGF_PRIORITY, nd6_timer_dispatch);
678 	callout_reset_bycpu(&nd6_timer_ch, hz, nd6_timer, NULL, 0);
679 }
680 
681 static int
682 regen_tmpaddr(struct in6_ifaddr *ia6) /* deprecated/invalidated temporary
683 					 address */
684 {
685 	struct ifaddr_container *ifac;
686 	struct ifnet *ifp;
687 	struct in6_ifaddr *public_ifa6 = NULL;
688 
689 	ifp = ia6->ia_ifa.ifa_ifp;
690 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
691 		struct ifaddr *ifa = ifac->ifa;
692 		struct in6_ifaddr *it6;
693 
694 		if (ifa->ifa_addr->sa_family != AF_INET6)
695 			continue;
696 
697 		it6 = (struct in6_ifaddr *)ifa;
698 
699 		/* ignore no autoconf addresses. */
700 		if (!(it6->ia6_flags & IN6_IFF_AUTOCONF))
701 			continue;
702 
703 		/* ignore autoconf addresses with different prefixes. */
704 		if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
705 			continue;
706 
707 		/*
708 		 * Now we are looking at an autoconf address with the same
709 		 * prefix as ours.  If the address is temporary and is still
710 		 * preferred, do not create another one.  It would be rare, but
711 		 * could happen, for example, when we resume a laptop PC after
712 		 * a long period.
713 		 */
714 		if ((it6->ia6_flags & IN6_IFF_TEMPORARY) &&
715 		    !IFA6_IS_DEPRECATED(it6)) {
716 			public_ifa6 = NULL;
717 			break;
718 		}
719 
720 		/*
721 		 * This is a public autoconf address that has the same prefix
722 		 * as ours.  If it is preferred, keep it.  We can't break the
723 		 * loop here, because there may be a still-preferred temporary
724 		 * address with the prefix.
725 		 */
726 		if (!IFA6_IS_DEPRECATED(it6))
727 		    public_ifa6 = it6;
728 	}
729 
730 	if (public_ifa6 != NULL) {
731 		int e;
732 
733 		if ((e = in6_tmpifadd(public_ifa6, 0)) != 0) {
734 			log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
735 			    " tmp addr,errno=%d\n", e);
736 			return (-1);
737 		}
738 		return (0);
739 	}
740 
741 	return (-1);
742 }
743 
744 /*
745  * Nuke neighbor cache/prefix/default router management table, right before
746  * ifp goes away.
747  */
748 void
749 nd6_purge(struct ifnet *ifp)
750 {
751 	struct llinfo_nd6 *ln, *nln;
752 	struct nd_defrouter *dr, *ndr, drany;
753 	struct nd_prefix *pr, *npr;
754 
755 	/* Nuke default router list entries toward ifp */
756 	if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
757 		/*
758 		 * The first entry of the list may be stored in
759 		 * the routing table, so we'll delete it later.
760 		 */
761 		for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = ndr) {
762 			ndr = TAILQ_NEXT(dr, dr_entry);
763 			if (dr->ifp == ifp)
764 				defrtrlist_del(dr);
765 		}
766 		dr = TAILQ_FIRST(&nd_defrouter);
767 		if (dr->ifp == ifp)
768 			defrtrlist_del(dr);
769 	}
770 
771 	/* Nuke prefix list entries toward ifp */
772 	for (pr = nd_prefix.lh_first; pr; pr = npr) {
773 		npr = pr->ndpr_next;
774 		if (pr->ndpr_ifp == ifp) {
775 			/*
776 			 * Previously, pr->ndpr_addr is removed as well,
777 			 * but I strongly believe we don't have to do it.
778 			 * nd6_purge() is only called from in6_ifdetach(),
779 			 * which removes all the associated interface addresses
780 			 * by itself.
781 			 * (jinmei@kame.net 20010129)
782 			 */
783 			prelist_remove(pr);
784 		}
785 	}
786 
787 	/* cancel default outgoing interface setting */
788 	if (nd6_defifindex == ifp->if_index)
789 		nd6_setdefaultiface(0);
790 
791 	if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
792 		/* refresh default router list */
793 		bzero(&drany, sizeof(drany));
794 		defrouter_delreq(&drany, 0);
795 		defrouter_select();
796 	}
797 
798 	/*
799 	 * Nuke neighbor cache entries for the ifp.
800 	 * Note that rt->rt_ifp may not be the same as ifp,
801 	 * due to KAME goto ours hack.  See RTM_RESOLVE case in
802 	 * nd6_rtrequest(), and ip6_input().
803 	 */
804 	ln = llinfo_nd6.ln_next;
805 	while (ln && ln != &llinfo_nd6) {
806 		struct rtentry *rt;
807 		struct sockaddr_dl *sdl;
808 
809 		nln = ln->ln_next;
810 		rt = ln->ln_rt;
811 		if (rt && rt->rt_gateway &&
812 		    rt->rt_gateway->sa_family == AF_LINK) {
813 			sdl = (struct sockaddr_dl *)rt->rt_gateway;
814 			if (sdl->sdl_index == ifp->if_index)
815 				nln = nd6_free(rt);
816 		}
817 		ln = nln;
818 	}
819 }
820 
821 struct rtentry *
822 nd6_lookup(struct in6_addr *addr6, int create, struct ifnet *ifp)
823 {
824 	struct rtentry *rt;
825 	struct sockaddr_in6 sin6;
826 
827 	bzero(&sin6, sizeof(sin6));
828 	sin6.sin6_len = sizeof(struct sockaddr_in6);
829 	sin6.sin6_family = AF_INET6;
830 	sin6.sin6_addr = *addr6;
831 
832 	if (create)
833 		rt = rtlookup((struct sockaddr *)&sin6);
834 	else
835 		rt = rtpurelookup((struct sockaddr *)&sin6);
836 	if (rt && !(rt->rt_flags & RTF_LLINFO)) {
837 		/*
838 		 * This is the case for the default route.
839 		 * If we want to create a neighbor cache for the address, we
840 		 * should free the route for the destination and allocate an
841 		 * interface route.
842 		 */
843 		if (create) {
844 			--rt->rt_refcnt;
845 			rt = NULL;
846 		}
847 	}
848 	if (!rt) {
849 		if (create && ifp) {
850 			int e;
851 
852 			/*
853 			 * If no route is available and create is set,
854 			 * we allocate a host route for the destination
855 			 * and treat it like an interface route.
856 			 * This hack is necessary for a neighbor which can't
857 			 * be covered by our own prefix.
858 			 */
859 			struct ifaddr *ifa =
860 				ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp);
861 			if (ifa == NULL)
862 				return (NULL);
863 
864 			/*
865 			 * Create a new route.  RTF_LLINFO is necessary
866 			 * to create a Neighbor Cache entry for the
867 			 * destination in nd6_rtrequest which will be
868 			 * called in rtrequest via ifa->ifa_rtrequest.
869 			 */
870 			if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6,
871 					   ifa->ifa_addr,
872 					   (struct sockaddr *)&all1_sa,
873 					   (ifa->ifa_flags |
874 					    RTF_HOST | RTF_LLINFO) &
875 					   ~RTF_CLONING,
876 					   &rt)) != 0)
877 				log(LOG_ERR,
878 				    "nd6_lookup: failed to add route for a "
879 				    "neighbor(%s), errno=%d\n",
880 				    ip6_sprintf(addr6), e);
881 			if (rt == NULL)
882 				return (NULL);
883 			if (rt->rt_llinfo) {
884 				struct llinfo_nd6 *ln =
885 					(struct llinfo_nd6 *)rt->rt_llinfo;
886 				ln->ln_state = ND6_LLINFO_NOSTATE;
887 			}
888 		} else
889 			return (NULL);
890 	}
891 	rt->rt_refcnt--;
892 	/*
893 	 * Validation for the entry.
894 	 * Note that the check for rt_llinfo is necessary because a cloned
895 	 * route from a parent route that has the L flag (e.g. the default
896 	 * route to a p2p interface) may have the flag, too, while the
897 	 * destination is not actually a neighbor.
898 	 * XXX: we can't use rt->rt_ifp to check for the interface, since
899 	 *      it might be the loopback interface if the entry is for our
900 	 *      own address on a non-loopback interface. Instead, we should
901 	 *      use rt->rt_ifa->ifa_ifp, which would specify the REAL
902 	 *      interface.
903 	 */
904 	if ((rt->rt_flags & RTF_GATEWAY) || !(rt->rt_flags & RTF_LLINFO) ||
905 	    rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL ||
906 	    (ifp && rt->rt_ifa->ifa_ifp != ifp)) {
907 		if (create) {
908 			log(LOG_DEBUG, "nd6_lookup: failed to lookup %s (if = %s)\n",
909 			    ip6_sprintf(addr6), ifp ? if_name(ifp) : "unspec");
910 			/* xxx more logs... kazu */
911 		}
912 		return (NULL);
913 	}
914 	return (rt);
915 }
916 
917 /*
918  * Detect if a given IPv6 address identifies a neighbor on a given link.
919  * XXX: should take care of the destination of a p2p link?
920  */
921 int
922 nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
923 {
924 	struct ifaddr_container *ifac;
925 	int i;
926 
927 #define IFADDR6(a) ((((struct in6_ifaddr *)(a))->ia_addr).sin6_addr)
928 #define IFMASK6(a) ((((struct in6_ifaddr *)(a))->ia_prefixmask).sin6_addr)
929 
930 	/*
931 	 * A link-local address is always a neighbor.
932 	 * XXX: we should use the sin6_scope_id field rather than the embedded
933 	 * interface index.
934 	 */
935 	if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr) &&
936 	    ntohs(*(u_int16_t *)&addr->sin6_addr.s6_addr[2]) == ifp->if_index)
937 		return (1);
938 
939 	/*
940 	 * If the address matches one of our addresses,
941 	 * it should be a neighbor.
942 	 */
943 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
944 		struct ifaddr *ifa = ifac->ifa;
945 
946 		if (ifa->ifa_addr->sa_family != AF_INET6)
947 			next: continue;
948 
949 		for (i = 0; i < 4; i++) {
950 			if ((IFADDR6(ifa).s6_addr32[i] ^
951 			     addr->sin6_addr.s6_addr32[i]) &
952 			    IFMASK6(ifa).s6_addr32[i])
953 				goto next;
954 		}
955 		return (1);
956 	}
957 
958 	/*
959 	 * Even if the address matches none of our addresses, it might be
960 	 * in the neighbor cache.
961 	 */
962 	if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL)
963 		return (1);
964 
965 	return (0);
966 #undef IFADDR6
967 #undef IFMASK6
968 }
969 
970 /*
971  * Free an nd6 llinfo entry.
972  */
973 struct llinfo_nd6 *
974 nd6_free(struct rtentry *rt)
975 {
976 	struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next;
977 	struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
978 	struct nd_defrouter *dr;
979 
980 	/*
981 	 * we used to have kpfctlinput(PRC_HOSTDEAD) here.
982 	 * even though it is not harmful, it was not really necessary.
983 	 */
984 
985 	if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
986 		mtx_lock(&nd6_mtx);
987 		dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
988 				      rt->rt_ifp);
989 
990 		if (ln->ln_router || dr) {
991 			/*
992 			 * rt6_flush must be called whether or not the neighbor
993 			 * is in the Default Router List.
994 			 * See a corresponding comment in nd6_na_input().
995 			 */
996 			rt6_flush(&in6, rt->rt_ifp);
997 		}
998 
999 		if (dr) {
1000 			/*
1001 			 * Unreachablity of a router might affect the default
1002 			 * router selection and on-link detection of advertised
1003 			 * prefixes.
1004 			 */
1005 
1006 			/*
1007 			 * Temporarily fake the state to choose a new default
1008 			 * router and to perform on-link determination of
1009 			 * prefixes correctly.
1010 			 * Below the state will be set correctly,
1011 			 * or the entry itself will be deleted.
1012 			 */
1013 			ln->ln_state = ND6_LLINFO_INCOMPLETE;
1014 
1015 			/*
1016 			 * Since defrouter_select() does not affect the
1017 			 * on-link determination and MIP6 needs the check
1018 			 * before the default router selection, we perform
1019 			 * the check now.
1020 			 */
1021 			pfxlist_onlink_check();
1022 
1023 			if (dr == TAILQ_FIRST(&nd_defrouter)) {
1024 				/*
1025 				 * It is used as the current default router,
1026 				 * so we have to move it to the end of the
1027 				 * list and choose a new one.
1028 				 * XXX: it is not very efficient if this is
1029 				 *      the only router.
1030 				 */
1031 				TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
1032 				TAILQ_INSERT_TAIL(&nd_defrouter, dr, dr_entry);
1033 
1034 				defrouter_select();
1035 			}
1036 		}
1037 		mtx_unlock(&nd6_mtx);
1038 	}
1039 
1040 	/*
1041 	 * Before deleting the entry, remember the next entry as the
1042 	 * return value.  We need this because pfxlist_onlink_check() above
1043 	 * might have freed other entries (particularly the old next entry) as
1044 	 * a side effect (XXX).
1045 	 */
1046 	next = ln->ln_next;
1047 
1048 	/*
1049 	 * Detach the route from the routing tree and the list of neighbor
1050 	 * caches, and disable the route entry not to be used in already
1051 	 * cached routes.
1052 	 */
1053 	rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
1054 
1055 	return (next);
1056 }
1057 
1058 /*
1059  * Upper-layer reachability hint for Neighbor Unreachability Detection.
1060  *
1061  * XXX cost-effective metods?
1062  */
1063 void
1064 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force)
1065 {
1066 	struct llinfo_nd6 *ln;
1067 
1068 	/*
1069 	 * If the caller specified "rt", use that.  Otherwise, resolve the
1070 	 * routing table by supplied "dst6".
1071 	 */
1072 	if (!rt) {
1073 		if (!dst6)
1074 			return;
1075 		if (!(rt = nd6_lookup(dst6, 0, NULL)))
1076 			return;
1077 	}
1078 
1079 	if ((rt->rt_flags & RTF_GATEWAY) ||
1080 	    !(rt->rt_flags & RTF_LLINFO) ||
1081 	    rt->rt_llinfo == NULL || rt->rt_gateway == NULL ||
1082 	    rt->rt_gateway->sa_family != AF_LINK) {
1083 		/* This is not a host route. */
1084 		return;
1085 	}
1086 
1087 	ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1088 	if (ln->ln_state < ND6_LLINFO_REACHABLE)
1089 		return;
1090 
1091 	/*
1092 	 * if we get upper-layer reachability confirmation many times,
1093 	 * it is possible we have false information.
1094 	 */
1095 	if (!force) {
1096 		ln->ln_byhint++;
1097 		if (ln->ln_byhint > nd6_maxnudhint)
1098 			return;
1099 	}
1100 
1101 	ln->ln_state = ND6_LLINFO_REACHABLE;
1102 	if (ln->ln_expire)
1103 		ln->ln_expire = time_uptime +
1104 			ND_IFINFO(rt->rt_ifp)->reachable;
1105 }
1106 
1107 void
1108 nd6_rtrequest(int req, struct rtentry *rt)
1109 {
1110 	struct sockaddr *gate = rt->rt_gateway;
1111 	struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1112 	static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
1113 	struct ifnet *ifp = rt->rt_ifp;
1114 	struct ifaddr *ifa;
1115 
1116 	if ((rt->rt_flags & RTF_GATEWAY))
1117 		return;
1118 
1119 	if (nd6_need_cache(ifp) == 0 && !(rt->rt_flags & RTF_HOST)) {
1120 		/*
1121 		 * This is probably an interface direct route for a link
1122 		 * which does not need neighbor caches (e.g. fe80::%lo0/64).
1123 		 * We do not need special treatment below for such a route.
1124 		 * Moreover, the RTF_LLINFO flag which would be set below
1125 		 * would annoy the ndp(8) command.
1126 		 */
1127 		return;
1128 	}
1129 
1130 	if (req == RTM_RESOLVE &&
1131 	    (nd6_need_cache(ifp) == 0 || /* stf case */
1132 	     !nd6_is_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), ifp))) {
1133 		/*
1134 		 * FreeBSD and BSD/OS often make a cloned host route based
1135 		 * on a less-specific route (e.g. the default route).
1136 		 * If the less specific route does not have a "gateway"
1137 		 * (this is the case when the route just goes to a p2p or an
1138 		 * stf interface), we'll mistakenly make a neighbor cache for
1139 		 * the host route, and will see strange neighbor solicitation
1140 		 * for the corresponding destination.  In order to avoid the
1141 		 * confusion, we check if the destination of the route is
1142 		 * a neighbor in terms of neighbor discovery, and stop the
1143 		 * process if not.  Additionally, we remove the LLINFO flag
1144 		 * so that ndp(8) will not try to get the neighbor information
1145 		 * of the destination.
1146 		 */
1147 		rt->rt_flags &= ~RTF_LLINFO;
1148 		return;
1149 	}
1150 
1151 	switch (req) {
1152 	case RTM_ADD:
1153 		/*
1154 		 * There is no backward compatibility :)
1155 		 *
1156 		 * if (!(rt->rt_flags & RTF_HOST) &&
1157 		 *     SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
1158 		 *	   rt->rt_flags |= RTF_CLONING;
1159 		 */
1160 		if (rt->rt_flags & (RTF_CLONING | RTF_LLINFO)) {
1161 			/*
1162 			 * Case 1: This route should come from
1163 			 * a route to interface.  RTF_LLINFO flag is set
1164 			 * for a host route whose destination should be
1165 			 * treated as on-link.
1166 			 */
1167 			rt_setgate(rt, rt_key(rt),
1168 				   (struct sockaddr *)&null_sdl,
1169 				   RTL_DONTREPORT);
1170 			gate = rt->rt_gateway;
1171 			SDL(gate)->sdl_type = ifp->if_type;
1172 			SDL(gate)->sdl_index = ifp->if_index;
1173 			if (ln)
1174 				ln->ln_expire = time_uptime;
1175 #if 1
1176 			if (ln && ln->ln_expire == 0) {
1177 				/* kludge for desktops */
1178 #if 0
1179 				kprintf("nd6_rtequest: time.tv_sec is zero; "
1180 				       "treat it as 1\n");
1181 #endif
1182 				ln->ln_expire = 1;
1183 			}
1184 #endif
1185 			if ((rt->rt_flags & RTF_CLONING))
1186 				break;
1187 		}
1188 		/*
1189 		 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here.
1190 		 * We don't do that here since llinfo is not ready yet.
1191 		 *
1192 		 * There are also couple of other things to be discussed:
1193 		 * - unsolicited NA code needs improvement beforehand
1194 		 * - RFC2461 says we MAY send multicast unsolicited NA
1195 		 *   (7.2.6 paragraph 4), however, it also says that we
1196 		 *   SHOULD provide a mechanism to prevent multicast NA storm.
1197 		 *   we don't have anything like it right now.
1198 		 *   note that the mechanism needs a mutual agreement
1199 		 *   between proxies, which means that we need to implement
1200 		 *   a new protocol, or a new kludge.
1201 		 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA.
1202 		 *   we need to check ip6forwarding before sending it.
1203 		 *   (or should we allow proxy ND configuration only for
1204 		 *   routers?  there's no mention about proxy ND from hosts)
1205 		 */
1206 #if 0
1207 		/* XXX it does not work */
1208 		if (rt->rt_flags & RTF_ANNOUNCE)
1209 			nd6_na_output(ifp,
1210 			      &SIN6(rt_key(rt))->sin6_addr,
1211 			      &SIN6(rt_key(rt))->sin6_addr,
1212 			      ip6_forwarding ? ND_NA_FLAG_ROUTER : 0,
1213 			      1, NULL);
1214 #endif
1215 		/* FALLTHROUGH */
1216 	case RTM_RESOLVE:
1217 		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) {
1218 			/*
1219 			 * Address resolution isn't necessary for a point to
1220 			 * point link, so we can skip this test for a p2p link.
1221 			 */
1222 			if (gate->sa_family != AF_LINK ||
1223 			    gate->sa_len < sizeof(null_sdl)) {
1224 				log(LOG_DEBUG,
1225 				    "nd6_rtrequest: bad gateway value: %s\n",
1226 				    if_name(ifp));
1227 				break;
1228 			}
1229 			SDL(gate)->sdl_type = ifp->if_type;
1230 			SDL(gate)->sdl_index = ifp->if_index;
1231 		}
1232 		if (ln != NULL)
1233 			break;	/* This happens on a route change */
1234 		/*
1235 		 * Case 2: This route may come from cloning, or a manual route
1236 		 * add with a LL address.
1237 		 */
1238 		R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln));
1239 		rt->rt_llinfo = (caddr_t)ln;
1240 		if (!ln) {
1241 			log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n");
1242 			break;
1243 		}
1244 		nd6_inuse++;
1245 		nd6_allocated++;
1246 		bzero(ln, sizeof(*ln));
1247 		ln->ln_rt = rt;
1248 		/* this is required for "ndp" command. - shin */
1249 		if (req == RTM_ADD) {
1250 		        /*
1251 			 * gate should have some valid AF_LINK entry,
1252 			 * and ln->ln_expire should have some lifetime
1253 			 * which is specified by ndp command.
1254 			 */
1255 			ln->ln_state = ND6_LLINFO_REACHABLE;
1256 			ln->ln_byhint = 0;
1257 		} else {
1258 		        /*
1259 			 * When req == RTM_RESOLVE, rt is created and
1260 			 * initialized in rtrequest(), so rt_expire is 0.
1261 			 */
1262 			ln->ln_state = ND6_LLINFO_NOSTATE;
1263 			ln->ln_expire = time_uptime;
1264 		}
1265 		rt->rt_flags |= RTF_LLINFO;
1266 		ln->ln_next = llinfo_nd6.ln_next;
1267 		llinfo_nd6.ln_next = ln;
1268 		ln->ln_prev = &llinfo_nd6;
1269 		ln->ln_next->ln_prev = ln;
1270 
1271 		/*
1272 		 * check if rt_key(rt) is one of my address assigned
1273 		 * to the interface.
1274 		 */
1275 		ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp,
1276 					  &SIN6(rt_key(rt))->sin6_addr);
1277 		if (ifa) {
1278 			caddr_t macp = nd6_ifptomac(ifp);
1279 			ln->ln_expire = 0;
1280 			ln->ln_state = ND6_LLINFO_REACHABLE;
1281 			ln->ln_byhint = 0;
1282 			if (macp) {
1283 				bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen);
1284 				SDL(gate)->sdl_alen = ifp->if_addrlen;
1285 			}
1286 			if (nd6_useloopback) {
1287 				rt->rt_ifp = &loif[0];	/* XXX */
1288 				/*
1289 				 * Make sure rt_ifa be equal to the ifaddr
1290 				 * corresponding to the address.
1291 				 * We need this because when we refer
1292 				 * rt_ifa->ia6_flags in ip6_input, we assume
1293 				 * that the rt_ifa points to the address instead
1294 				 * of the loopback address.
1295 				 */
1296 				if (ifa != rt->rt_ifa) {
1297 					IFAFREE(rt->rt_ifa);
1298 					IFAREF(ifa);
1299 					rt->rt_ifa = ifa;
1300 				}
1301 			}
1302 		} else if (rt->rt_flags & RTF_ANNOUNCE) {
1303 			ln->ln_expire = 0;
1304 			ln->ln_state = ND6_LLINFO_REACHABLE;
1305 			ln->ln_byhint = 0;
1306 
1307 			/* join solicited node multicast for proxy ND */
1308 			if (ifp->if_flags & IFF_MULTICAST) {
1309 				struct in6_addr llsol;
1310 				int error;
1311 
1312 				llsol = SIN6(rt_key(rt))->sin6_addr;
1313 				llsol.s6_addr16[0] = htons(0xff02);
1314 				llsol.s6_addr16[1] = htons(ifp->if_index);
1315 				llsol.s6_addr32[1] = 0;
1316 				llsol.s6_addr32[2] = htonl(1);
1317 				llsol.s6_addr8[12] = 0xff;
1318 
1319 				if (!in6_addmulti(&llsol, ifp, &error)) {
1320 					nd6log((LOG_ERR, "%s: failed to join "
1321 					    "%s (errno=%d)\n", if_name(ifp),
1322 					    ip6_sprintf(&llsol), error));
1323 				}
1324 			}
1325 		}
1326 		break;
1327 
1328 	case RTM_DELETE:
1329 		if (!ln)
1330 			break;
1331 		/* leave from solicited node multicast for proxy ND */
1332 		if ((rt->rt_flags & RTF_ANNOUNCE) &&
1333 		    (ifp->if_flags & IFF_MULTICAST)) {
1334 			struct in6_addr llsol;
1335 			struct in6_multi *in6m;
1336 
1337 			llsol = SIN6(rt_key(rt))->sin6_addr;
1338 			llsol.s6_addr16[0] = htons(0xff02);
1339 			llsol.s6_addr16[1] = htons(ifp->if_index);
1340 			llsol.s6_addr32[1] = 0;
1341 			llsol.s6_addr32[2] = htonl(1);
1342 			llsol.s6_addr8[12] = 0xff;
1343 
1344 			in6m = IN6_LOOKUP_MULTI(&llsol, ifp);
1345 			if (in6m)
1346 				in6_delmulti(in6m);
1347 		}
1348 		nd6_inuse--;
1349 		ln->ln_next->ln_prev = ln->ln_prev;
1350 		ln->ln_prev->ln_next = ln->ln_next;
1351 		ln->ln_prev = NULL;
1352 		rt->rt_llinfo = 0;
1353 		rt->rt_flags &= ~RTF_LLINFO;
1354 		if (ln->ln_hold)
1355 			m_freem(ln->ln_hold);
1356 		Free((caddr_t)ln);
1357 	}
1358 }
1359 
1360 int
1361 nd6_ioctl(u_long cmd, caddr_t	data, struct ifnet *ifp)
1362 {
1363 	struct in6_drlist *drl = (struct in6_drlist *)data;
1364 	struct in6_prlist *prl = (struct in6_prlist *)data;
1365 	struct in6_ndireq *ndi = (struct in6_ndireq *)data;
1366 	struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
1367 	struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
1368 	struct nd_defrouter *dr, any;
1369 	struct nd_prefix *pr;
1370 	struct rtentry *rt;
1371 	int i = 0, error = 0;
1372 
1373 	switch (cmd) {
1374 	case SIOCGDRLST_IN6:
1375 		/*
1376 		 * obsolete API, use sysctl under net.inet6.icmp6
1377 		 */
1378 		bzero(drl, sizeof(*drl));
1379 		mtx_lock(&nd6_mtx);
1380 		dr = TAILQ_FIRST(&nd_defrouter);
1381 		while (dr && i < DRLSTSIZ) {
1382 			drl->defrouter[i].rtaddr = dr->rtaddr;
1383 			if (IN6_IS_ADDR_LINKLOCAL(&drl->defrouter[i].rtaddr)) {
1384 				/* XXX: need to this hack for KAME stack */
1385 				drl->defrouter[i].rtaddr.s6_addr16[1] = 0;
1386 			} else
1387 				log(LOG_ERR,
1388 				    "default router list contains a "
1389 				    "non-linklocal address(%s)\n",
1390 				    ip6_sprintf(&drl->defrouter[i].rtaddr));
1391 
1392 			drl->defrouter[i].flags = dr->flags;
1393 			drl->defrouter[i].rtlifetime = dr->rtlifetime;
1394 			drl->defrouter[i].expire = dr->expire;
1395 			drl->defrouter[i].if_index = dr->ifp->if_index;
1396 			i++;
1397 			dr = TAILQ_NEXT(dr, dr_entry);
1398 		}
1399 		mtx_unlock(&nd6_mtx);
1400 		break;
1401 	case SIOCGPRLST_IN6:
1402 		/*
1403 		 * obsolete API, use sysctl under net.inet6.icmp6
1404 		 */
1405 		/*
1406 		 * XXX meaning of fields, especialy "raflags", is very
1407 		 * differnet between RA prefix list and RR/static prefix list.
1408 		 * how about separating ioctls into two?
1409 		 */
1410 		bzero(prl, sizeof(*prl));
1411 		mtx_lock(&nd6_mtx);
1412 		pr = nd_prefix.lh_first;
1413 		while (pr && i < PRLSTSIZ) {
1414 			struct nd_pfxrouter *pfr;
1415 			int j;
1416 
1417 			in6_embedscope(&prl->prefix[i].prefix,
1418 			    &pr->ndpr_prefix, NULL, NULL);
1419 			prl->prefix[i].raflags = pr->ndpr_raf;
1420 			prl->prefix[i].prefixlen = pr->ndpr_plen;
1421 			prl->prefix[i].vltime = pr->ndpr_vltime;
1422 			prl->prefix[i].pltime = pr->ndpr_pltime;
1423 			prl->prefix[i].if_index = pr->ndpr_ifp->if_index;
1424 			prl->prefix[i].expire = pr->ndpr_expire;
1425 
1426 			pfr = pr->ndpr_advrtrs.lh_first;
1427 			j = 0;
1428 			while (pfr) {
1429 				if (j < DRLSTSIZ) {
1430 #define RTRADDR prl->prefix[i].advrtr[j]
1431 					RTRADDR = pfr->router->rtaddr;
1432 					if (IN6_IS_ADDR_LINKLOCAL(&RTRADDR)) {
1433 						/* XXX: hack for KAME */
1434 						RTRADDR.s6_addr16[1] = 0;
1435 					} else
1436 						log(LOG_ERR,
1437 						    "a router(%s) advertises "
1438 						    "a prefix with "
1439 						    "non-link local address\n",
1440 						    ip6_sprintf(&RTRADDR));
1441 #undef RTRADDR
1442 				}
1443 				j++;
1444 				pfr = pfr->pfr_next;
1445 			}
1446 			prl->prefix[i].advrtrs = j;
1447 			prl->prefix[i].origin = PR_ORIG_RA;
1448 
1449 			i++;
1450 			pr = pr->ndpr_next;
1451 		}
1452 		mtx_unlock(&nd6_mtx);
1453 
1454 		break;
1455 	case OSIOCGIFINFO_IN6:
1456 		/* XXX: old ndp(8) assumes a positive value for linkmtu. */
1457 		bzero(&ndi->ndi, sizeof(ndi->ndi));
1458 		ndi->ndi.linkmtu = ND_IFINFO(ifp)->linkmtu;
1459 		ndi->ndi.maxmtu = ND_IFINFO(ifp)->maxmtu;
1460 		ndi->ndi.basereachable = ND_IFINFO(ifp)->basereachable;
1461 		ndi->ndi.reachable = ND_IFINFO(ifp)->reachable;
1462 		ndi->ndi.retrans = ND_IFINFO(ifp)->retrans;
1463 		ndi->ndi.flags = ND_IFINFO(ifp)->flags;
1464 		ndi->ndi.recalctm = ND_IFINFO(ifp)->recalctm;
1465 		ndi->ndi.chlim = ND_IFINFO(ifp)->chlim;
1466 		ndi->ndi.receivedra = ND_IFINFO(ifp)->receivedra;
1467 		break;
1468 	case SIOCGIFINFO_IN6:
1469 		ndi->ndi = *ND_IFINFO(ifp);
1470 		break;
1471 	case SIOCSIFINFO_FLAGS:
1472 		ND_IFINFO(ifp)->flags = ndi->ndi.flags;
1473 		break;
1474 	case SIOCSNDFLUSH_IN6:	/* XXX: the ioctl name is confusing... */
1475 		/* flush default router list */
1476 		/*
1477 		 * xxx sumikawa: should not delete route if default
1478 		 * route equals to the top of default router list
1479 		 */
1480 		bzero(&any, sizeof(any));
1481 		defrouter_delreq(&any, 0);
1482 		defrouter_select();
1483 		/* xxx sumikawa: flush prefix list */
1484 		break;
1485 	case SIOCSPFXFLUSH_IN6:
1486 	    {
1487 		/* flush all the prefix advertised by routers */
1488 		struct nd_prefix *pr, *next;
1489 
1490 		mtx_lock(&nd6_mtx);
1491 		for (pr = nd_prefix.lh_first; pr; pr = next) {
1492 			struct in6_ifaddr *ia, *ia_next;
1493 
1494 			next = pr->ndpr_next;
1495 
1496 			if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1497 				continue; /* XXX */
1498 
1499 			/* do we really have to remove addresses as well? */
1500 			for (ia = in6_ifaddr; ia; ia = ia_next) {
1501 				/* ia might be removed.  keep the next ptr. */
1502 				ia_next = ia->ia_next;
1503 
1504 				if (!(ia->ia6_flags & IN6_IFF_AUTOCONF))
1505 					continue;
1506 
1507 				if (ia->ia6_ndpr == pr)
1508 					in6_purgeaddr(&ia->ia_ifa);
1509 			}
1510 			prelist_remove(pr);
1511 		}
1512 		mtx_unlock(&nd6_mtx);
1513 		break;
1514 	    }
1515 	case SIOCSRTRFLUSH_IN6:
1516 	    {
1517 		/* flush all the default routers */
1518 		struct nd_defrouter *dr, *next;
1519 
1520 		mtx_lock(&nd6_mtx);
1521 		if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
1522 			/*
1523 			 * The first entry of the list may be stored in
1524 			 * the routing table, so we'll delete it later.
1525 			 */
1526 			for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = next) {
1527 				next = TAILQ_NEXT(dr, dr_entry);
1528 				defrtrlist_del(dr);
1529 			}
1530 			defrtrlist_del(TAILQ_FIRST(&nd_defrouter));
1531 		}
1532 		mtx_unlock(&nd6_mtx);
1533 		break;
1534 	    }
1535 	case SIOCGNBRINFO_IN6:
1536 	    {
1537 		struct llinfo_nd6 *ln;
1538 		struct in6_addr nb_addr = nbi->addr; /* make local for safety */
1539 
1540 		/*
1541 		 * XXX: KAME specific hack for scoped addresses
1542 		 *      XXXX: for other scopes than link-local?
1543 		 */
1544 		if (IN6_IS_ADDR_LINKLOCAL(&nbi->addr) ||
1545 		    IN6_IS_ADDR_MC_LINKLOCAL(&nbi->addr)) {
1546 			u_int16_t *idp = (u_int16_t *)&nb_addr.s6_addr[2];
1547 
1548 			if (*idp == 0)
1549 				*idp = htons(ifp->if_index);
1550 		}
1551 
1552 		mtx_lock(&nd6_mtx);
1553 		if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL) {
1554 			error = EINVAL;
1555 			mtx_unlock(&nd6_mtx);
1556 			break;
1557 		}
1558 		ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1559 		nbi->state = ln->ln_state;
1560 		nbi->asked = ln->ln_asked;
1561 		nbi->isrouter = ln->ln_router;
1562 		nbi->expire = ln->ln_expire;
1563 		mtx_unlock(&nd6_mtx);
1564 
1565 		break;
1566 	    }
1567 	case SIOCGDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
1568 		ndif->ifindex = nd6_defifindex;
1569 		break;
1570 	case SIOCSDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
1571 		return (nd6_setdefaultiface(ndif->ifindex));
1572 		break;
1573 	}
1574 	return (error);
1575 }
1576 
1577 /*
1578  * Create neighbor cache entry and cache link-layer address,
1579  * on reception of inbound ND6 packets. (RS/RA/NS/redirect)
1580  */
1581 struct rtentry *
1582 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr,
1583 		 int lladdrlen,
1584 		 int type,	/* ICMP6 type */
1585 		 int code	/* type dependent information */)
1586 {
1587 	struct rtentry *rt = NULL;
1588 	struct llinfo_nd6 *ln = NULL;
1589 	int is_newentry;
1590 	struct sockaddr_dl *sdl = NULL;
1591 	int do_update;
1592 	int olladdr;
1593 	int llchange;
1594 	int newstate = 0;
1595 
1596 	if (!ifp)
1597 		panic("ifp == NULL in nd6_cache_lladdr");
1598 	if (!from)
1599 		panic("from == NULL in nd6_cache_lladdr");
1600 
1601 	/* nothing must be updated for unspecified address */
1602 	if (IN6_IS_ADDR_UNSPECIFIED(from))
1603 		return NULL;
1604 
1605 	/*
1606 	 * Validation about ifp->if_addrlen and lladdrlen must be done in
1607 	 * the caller.
1608 	 *
1609 	 * XXX If the link does not have link-layer adderss, what should
1610 	 * we do? (ifp->if_addrlen == 0)
1611 	 * Spec says nothing in sections for RA, RS and NA.  There's small
1612 	 * description on it in NS section (RFC 2461 7.2.3).
1613 	 */
1614 
1615 	rt = nd6_lookup(from, 0, ifp);
1616 	if (!rt) {
1617 #if 0
1618 		/* nothing must be done if there's no lladdr */
1619 		if (!lladdr || !lladdrlen)
1620 			return NULL;
1621 #endif
1622 
1623 		rt = nd6_lookup(from, 1, ifp);
1624 		is_newentry = 1;
1625 	} else {
1626 		/* do nothing if static ndp is set */
1627 		if (rt->rt_flags & RTF_STATIC)
1628 			return NULL;
1629 		is_newentry = 0;
1630 	}
1631 
1632 	if (!rt)
1633 		return NULL;
1634 	if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) {
1635 fail:
1636 		nd6_free(rt);
1637 		return NULL;
1638 	}
1639 	ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1640 	if (!ln)
1641 		goto fail;
1642 	if (!rt->rt_gateway)
1643 		goto fail;
1644 	if (rt->rt_gateway->sa_family != AF_LINK)
1645 		goto fail;
1646 	sdl = SDL(rt->rt_gateway);
1647 
1648 	olladdr = (sdl->sdl_alen) ? 1 : 0;
1649 	if (olladdr && lladdr) {
1650 		if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
1651 			llchange = 1;
1652 		else
1653 			llchange = 0;
1654 	} else
1655 		llchange = 0;
1656 
1657 	/*
1658 	 * newentry olladdr  lladdr  llchange	(*=record)
1659 	 *	0	n	n	--	(1)
1660 	 *	0	y	n	--	(2)
1661 	 *	0	n	y	--	(3) * STALE
1662 	 *	0	y	y	n	(4) *
1663 	 *	0	y	y	y	(5) * STALE
1664 	 *	1	--	n	--	(6)   NOSTATE(= PASSIVE)
1665 	 *	1	--	y	--	(7) * STALE
1666 	 */
1667 
1668 	if (lladdr) {		/* (3-5) and (7) */
1669 		/*
1670 		 * Record source link-layer address
1671 		 * XXX is it dependent to ifp->if_type?
1672 		 */
1673 		sdl->sdl_alen = ifp->if_addrlen;
1674 		bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
1675 	}
1676 
1677 	if (!is_newentry) {
1678 		if ((!olladdr && lladdr)		/* (3) */
1679 		 || (olladdr && lladdr && llchange)) {	/* (5) */
1680 			do_update = 1;
1681 			newstate = ND6_LLINFO_STALE;
1682 		} else					/* (1-2,4) */
1683 			do_update = 0;
1684 	} else {
1685 		do_update = 1;
1686 		if (!lladdr)				/* (6) */
1687 			newstate = ND6_LLINFO_NOSTATE;
1688 		else					/* (7) */
1689 			newstate = ND6_LLINFO_STALE;
1690 	}
1691 
1692 	if (do_update) {
1693 		/*
1694 		 * Update the state of the neighbor cache.
1695 		 */
1696 		ln->ln_state = newstate;
1697 
1698 		if (ln->ln_state == ND6_LLINFO_STALE) {
1699 			/*
1700 			 * XXX: since nd6_output() below will cause
1701 			 * state tansition to DELAY and reset the timer,
1702 			 * we must set the timer now, although it is actually
1703 			 * meaningless.
1704 			 */
1705 			ln->ln_expire = time_uptime + nd6_gctimer;
1706 
1707 			if (ln->ln_hold) {
1708 				/*
1709 				 * we assume ifp is not a p2p here, so just
1710 				 * set the 2nd argument as the 1st one.
1711 				 */
1712 				nd6_output(ifp, ifp, ln->ln_hold,
1713 					   (struct sockaddr_in6 *)rt_key(rt),
1714 					   rt);
1715 				ln->ln_hold = NULL;
1716 			}
1717 		} else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
1718 			/* probe right away */
1719 			ln->ln_expire = time_uptime;
1720 		}
1721 	}
1722 
1723 	/*
1724 	 * ICMP6 type dependent behavior.
1725 	 *
1726 	 * NS: clear IsRouter if new entry
1727 	 * RS: clear IsRouter
1728 	 * RA: set IsRouter if there's lladdr
1729 	 * redir: clear IsRouter if new entry
1730 	 *
1731 	 * RA case, (1):
1732 	 * The spec says that we must set IsRouter in the following cases:
1733 	 * - If lladdr exist, set IsRouter.  This means (1-5).
1734 	 * - If it is old entry (!newentry), set IsRouter.  This means (7).
1735 	 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1736 	 * A quetion arises for (1) case.  (1) case has no lladdr in the
1737 	 * neighbor cache, this is similar to (6).
1738 	 * This case is rare but we figured that we MUST NOT set IsRouter.
1739 	 *
1740 	 * newentry olladdr  lladdr  llchange	    NS  RS  RA	redir
1741 	 *							D R
1742 	 *	0	n	n	--	(1)	c   ?     s
1743 	 *	0	y	n	--	(2)	c   s     s
1744 	 *	0	n	y	--	(3)	c   s     s
1745 	 *	0	y	y	n	(4)	c   s     s
1746 	 *	0	y	y	y	(5)	c   s     s
1747 	 *	1	--	n	--	(6) c	c 	c s
1748 	 *	1	--	y	--	(7) c	c   s	c s
1749 	 *
1750 	 *					(c=clear s=set)
1751 	 */
1752 	switch (type & 0xff) {
1753 	case ND_NEIGHBOR_SOLICIT:
1754 		/*
1755 		 * New entry must have is_router flag cleared.
1756 		 */
1757 		if (is_newentry)	/* (6-7) */
1758 			ln->ln_router = 0;
1759 		break;
1760 	case ND_REDIRECT:
1761 		/*
1762 		 * If the icmp is a redirect to a better router, always set the
1763 		 * is_router flag. Otherwise, if the entry is newly created,
1764 		 * clear the flag. [RFC 2461, sec 8.3]
1765 		 */
1766 		if (code == ND_REDIRECT_ROUTER)
1767 			ln->ln_router = 1;
1768 		else if (is_newentry) /* (6-7) */
1769 			ln->ln_router = 0;
1770 		break;
1771 	case ND_ROUTER_SOLICIT:
1772 		/*
1773 		 * is_router flag must always be cleared.
1774 		 */
1775 		ln->ln_router = 0;
1776 		break;
1777 	case ND_ROUTER_ADVERT:
1778 		/*
1779 		 * Mark an entry with lladdr as a router.
1780 		 */
1781 		if ((!is_newentry && (olladdr || lladdr))	/* (2-5) */
1782 		 || (is_newentry && lladdr)) {			/* (7) */
1783 			ln->ln_router = 1;
1784 		}
1785 		break;
1786 	}
1787 
1788 	/*
1789 	 * When the link-layer address of a router changes, select the
1790 	 * best router again.  In particular, when the neighbor entry is newly
1791 	 * created, it might affect the selection policy.
1792 	 * Question: can we restrict the first condition to the "is_newentry"
1793 	 * case?
1794 	 * XXX: when we hear an RA from a new router with the link-layer
1795 	 * address option, defrouter_select() is called twice, since
1796 	 * defrtrlist_update called the function as well.  However, I believe
1797 	 * we can compromise the overhead, since it only happens the first
1798 	 * time.
1799 	 * XXX: although defrouter_select() should not have a bad effect
1800 	 * for those are not autoconfigured hosts, we explicitly avoid such
1801 	 * cases for safety.
1802 	 */
1803 	if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv)
1804 		defrouter_select();
1805 
1806 	return rt;
1807 }
1808 
1809 static void
1810 nd6_slowtimo(void *arg __unused)
1811 {
1812 	struct lwkt_msg *lmsg = &nd6_slowtimo_netmsg.lmsg;
1813 
1814 	KASSERT(mycpuid == 0, ("not on cpu0"));
1815 	crit_enter();
1816 	if (lmsg->ms_flags & MSGF_DONE)
1817 		lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg);
1818 	crit_exit();
1819 }
1820 
1821 static void
1822 nd6_slowtimo_dispatch(netmsg_t nmsg)
1823 {
1824 	const struct ifnet_array *arr;
1825 	struct nd_ifinfo *nd6if;
1826 	int i;
1827 
1828 	ASSERT_IN_NETISR(0);
1829 
1830 	crit_enter();
1831 	lwkt_replymsg(&nmsg->lmsg, 0);	/* reply ASAP */
1832 	crit_exit();
1833 
1834 	arr = ifnet_array_get();
1835 
1836 	mtx_lock(&nd6_mtx);
1837 	for (i = 0; i < arr->ifnet_count; ++i) {
1838 		struct ifnet *ifp = arr->ifnet_arr[i];
1839 
1840 		if (ifp->if_afdata[AF_INET6] == NULL)
1841 			continue;
1842 		nd6if = ND_IFINFO(ifp);
1843 		if (nd6if->basereachable && /* already initialized */
1844 		    (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
1845 			/*
1846 			 * Since reachable time rarely changes by router
1847 			 * advertisements, we SHOULD insure that a new random
1848 			 * value gets recomputed at least once every few hours.
1849 			 * (RFC 2461, 6.3.4)
1850 			 */
1851 			nd6if->recalctm = nd6_recalc_reachtm_interval;
1852 			nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
1853 		}
1854 	}
1855 	mtx_unlock(&nd6_mtx);
1856 
1857 	callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
1858 	    nd6_slowtimo, NULL);
1859 }
1860 
1861 #define gotoerr(e) { error = (e); goto bad;}
1862 
1863 int
1864 nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1865 	   struct sockaddr_in6 *dst, struct rtentry *rt)
1866 {
1867 	struct llinfo_nd6 *ln = NULL;
1868 	int error = 0;
1869 
1870 	if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1871 		goto sendpkt;
1872 
1873 	if (nd6_need_cache(ifp) == 0)
1874 		goto sendpkt;
1875 
1876 	/*
1877 	 * next hop determination.  This routine is derived from ether_outpout.
1878 	 */
1879 	if (rt != NULL) {
1880 		if (!(rt->rt_flags & RTF_UP)) {
1881 			rt = rtlookup((struct sockaddr *)dst);
1882 			if (rt == NULL)
1883 				gotoerr(EHOSTUNREACH);
1884 			rt->rt_refcnt--;
1885 			if (rt->rt_ifp != ifp) {
1886 				/* XXX: loop care? */
1887 				return nd6_output(ifp, origifp, m, dst, rt);
1888 			}
1889 		}
1890 		if (rt->rt_flags & RTF_GATEWAY) {
1891 			struct sockaddr_in6 *gw6;
1892 
1893 			/*
1894 			 * We skip link-layer address resolution and NUD
1895 			 * if the gateway is not a neighbor from ND point
1896 			 * of view, regardless of the value of nd_ifinfo.flags.
1897 			 * The second condition is a bit tricky; we skip
1898 			 * if the gateway is our own address, which is
1899 			 * sometimes used to install a route to a p2p link.
1900 			 */
1901 			gw6 = (struct sockaddr_in6 *)rt->rt_gateway;
1902 			if (!nd6_is_addr_neighbor(gw6, ifp) ||
1903 			    in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) {
1904 				/*
1905 				 * We allow this kind of tricky route only
1906 				 * when the outgoing interface is p2p.
1907 				 * XXX: we may need a more generic rule here.
1908 				 */
1909 				if (!(ifp->if_flags & IFF_POINTOPOINT))
1910 					gotoerr(EHOSTUNREACH);
1911 
1912 				goto sendpkt;
1913 			}
1914 
1915 			if (rt->rt_gwroute == NULL) {
1916 				rt->rt_gwroute = rtlookup(rt->rt_gateway);
1917 				if (rt->rt_gwroute == NULL)
1918 					gotoerr(EHOSTUNREACH);
1919 			} else if (!(rt->rt_gwroute->rt_flags & RTF_UP)) {
1920 				rtfree(rt->rt_gwroute);
1921 				rt->rt_gwroute = rtlookup(rt->rt_gateway);
1922 				if (rt->rt_gwroute == NULL)
1923 					gotoerr(EHOSTUNREACH);
1924 			}
1925 		}
1926 	}
1927 
1928 	/*
1929 	 * Address resolution or Neighbor Unreachability Detection
1930 	 * for the next hop.
1931 	 * At this point, the destination of the packet must be a unicast
1932 	 * or an anycast address(i.e. not a multicast).
1933 	 */
1934 
1935 	/* Look up the neighbor cache for the nexthop */
1936 	if (rt && (rt->rt_flags & RTF_LLINFO))
1937 		ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1938 	else {
1939 		/*
1940 		 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
1941 		 * the condition below is not very efficient.  But we believe
1942 		 * it is tolerable, because this should be a rare case.
1943 		 */
1944 		if (nd6_is_addr_neighbor(dst, ifp) &&
1945 		    (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL)
1946 			ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1947 	}
1948 	if (!ln || !rt) {
1949 		if (!(ifp->if_flags & IFF_POINTOPOINT) &&
1950 		    !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) {
1951 			log(LOG_DEBUG,
1952 			    "nd6_output: can't allocate llinfo for %s "
1953 			    "(ln=%p, rt=%p)\n",
1954 			    ip6_sprintf(&dst->sin6_addr), ln, rt);
1955 			gotoerr(EIO);	/* XXX: good error? */
1956 		}
1957 
1958 		goto sendpkt;	/* send anyway */
1959 	}
1960 
1961 	/* We don't have to do link-layer address resolution on a p2p link. */
1962 	if ((ifp->if_flags & IFF_POINTOPOINT) &&
1963 	    ln->ln_state < ND6_LLINFO_REACHABLE) {
1964 		ln->ln_state = ND6_LLINFO_STALE;
1965 		ln->ln_expire = time_uptime + nd6_gctimer;
1966 	}
1967 
1968 	/*
1969 	 * The first time we send a packet to a neighbor whose entry is
1970 	 * STALE, we have to change the state to DELAY and a sets a timer to
1971 	 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
1972 	 * neighbor unreachability detection on expiration.
1973 	 * (RFC 2461 7.3.3)
1974 	 */
1975 	if (ln->ln_state == ND6_LLINFO_STALE) {
1976 		ln->ln_asked = 0;
1977 		ln->ln_state = ND6_LLINFO_DELAY;
1978 		ln->ln_expire = time_uptime + nd6_delay;
1979 	}
1980 
1981 	/*
1982 	 * If the neighbor cache entry has a state other than INCOMPLETE
1983 	 * (i.e. its link-layer address is already resolved), just
1984 	 * send the packet.
1985 	 */
1986 	if (ln->ln_state > ND6_LLINFO_INCOMPLETE)
1987 		goto sendpkt;
1988 
1989 	/*
1990 	 * There is a neighbor cache entry, but no ethernet address
1991 	 * response yet.  Replace the held mbuf (if any) with this
1992 	 * latest one.
1993 	 *
1994 	 * This code conforms to the rate-limiting rule described in Section
1995 	 * 7.2.2 of RFC 2461, because the timer is set correctly after sending
1996 	 * an NS below.
1997 	 */
1998 	if (ln->ln_state == ND6_LLINFO_NOSTATE)
1999 		ln->ln_state = ND6_LLINFO_INCOMPLETE;
2000 	if (ln->ln_hold)
2001 		m_freem(ln->ln_hold);
2002 	ln->ln_hold = m;
2003 	if (ln->ln_expire) {
2004 		if (ln->ln_asked < nd6_mmaxtries &&
2005 		    ln->ln_expire < time_uptime) {
2006 			ln->ln_asked++;
2007 			ln->ln_expire = time_uptime +
2008 				ND_IFINFO(ifp)->retrans / 1000;
2009 			nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0);
2010 		}
2011 	}
2012 	return (0);
2013 
2014 sendpkt:
2015 	if (ifp->if_flags & IFF_LOOPBACK)
2016 		error = ifp->if_output(origifp, m, (struct sockaddr *)dst, rt);
2017 	else
2018 		error = ifp->if_output(ifp, m, (struct sockaddr *)dst, rt);
2019 	return (error);
2020 
2021 bad:
2022 	m_freem(m);
2023 	return (error);
2024 }
2025 #undef gotoerr
2026 
2027 int
2028 nd6_need_cache(struct ifnet *ifp)
2029 {
2030 	/*
2031 	 * XXX: we currently do not make neighbor cache on any interface
2032 	 * other than Ethernet and GIF.
2033 	 *
2034 	 * RFC2893 says:
2035 	 * - unidirectional tunnels needs no ND
2036 	 */
2037 	switch (ifp->if_type) {
2038 	case IFT_ETHER:
2039 	case IFT_IEEE1394:
2040 #ifdef IFT_L2VLAN
2041 	case IFT_L2VLAN:
2042 #endif
2043 #ifdef IFT_IEEE80211
2044 	case IFT_IEEE80211:
2045 #endif
2046 #ifdef IFT_CARP
2047 	case IFT_CARP:
2048 #endif
2049 	case IFT_GIF:		/* XXX need more cases? */
2050 		return (1);
2051 	default:
2052 		return (0);
2053 	}
2054 }
2055 
2056 int
2057 nd6_storelladdr(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
2058 		struct sockaddr *dst, u_char *desten)
2059 {
2060 	struct sockaddr_dl *sdl;
2061 	struct rtentry *rt;
2062 
2063 
2064 	if (m->m_flags & M_MCAST) {
2065 		switch (ifp->if_type) {
2066 		case IFT_ETHER:
2067 #ifdef IFT_L2VLAN
2068 	case IFT_L2VLAN:
2069 #endif
2070 #ifdef IFT_IEEE80211
2071 		case IFT_IEEE80211:
2072 #endif
2073 			ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr,
2074 						 desten);
2075 			return (1);
2076 		case IFT_IEEE1394:
2077 			bcopy(ifp->if_broadcastaddr, desten, ifp->if_addrlen);
2078 			return (1);
2079 		default:
2080 			m_freem(m);
2081 			return (0);
2082 		}
2083 	}
2084 	if (rt0 == NULL) {
2085 		/* this could happen, if we could not allocate memory */
2086 		m_freem(m);
2087 		return (0);
2088 	}
2089 	if (rt_llroute(dst, rt0, &rt) != 0) {
2090 		m_freem(m);
2091 		return (0);
2092 	}
2093 	if (rt->rt_gateway->sa_family != AF_LINK) {
2094 		kprintf("nd6_storelladdr: something odd happens\n");
2095 		m_freem(m);
2096 		return (0);
2097 	}
2098 	sdl = SDL(rt->rt_gateway);
2099 	if (sdl->sdl_alen == 0) {
2100 		/* this should be impossible, but we bark here for debugging */
2101 		kprintf("nd6_storelladdr: sdl_alen == 0\n");
2102 		m_freem(m);
2103 		return (0);
2104 	}
2105 
2106 	bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
2107 	return (1);
2108 }
2109 
2110 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
2111 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
2112 #ifdef SYSCTL_DECL
2113 SYSCTL_DECL(_net_inet6_icmp6);
2114 #endif
2115 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2116 	CTLFLAG_RD, nd6_sysctl_drlist, "List default routers");
2117 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
2118 	CTLFLAG_RD, nd6_sysctl_prlist, "List prefixes");
2119 
2120 static int
2121 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2122 {
2123 	int error;
2124 	char buf[1024];
2125 	struct in6_defrouter *d, *de;
2126 	struct nd_defrouter *dr;
2127 
2128 	if (req->newptr)
2129 		return EPERM;
2130 	error = 0;
2131 
2132 	for (dr = TAILQ_FIRST(&nd_defrouter);
2133 	     dr;
2134 	     dr = TAILQ_NEXT(dr, dr_entry)) {
2135 		d = (struct in6_defrouter *)buf;
2136 		de = (struct in6_defrouter *)(buf + sizeof(buf));
2137 
2138 		if (d + 1 <= de) {
2139 			bzero(d, sizeof(*d));
2140 			d->rtaddr.sin6_family = AF_INET6;
2141 			d->rtaddr.sin6_len = sizeof(d->rtaddr);
2142 			if (in6_recoverscope(&d->rtaddr, &dr->rtaddr,
2143 			    dr->ifp) != 0)
2144 				log(LOG_ERR,
2145 				    "scope error in "
2146 				    "default router list (%s)\n",
2147 				    ip6_sprintf(&dr->rtaddr));
2148 			d->flags = dr->flags;
2149 			d->rtlifetime = dr->rtlifetime;
2150 			d->expire = dr->expire;
2151 			d->if_index = dr->ifp->if_index;
2152 		} else
2153 			panic("buffer too short");
2154 
2155 		error = SYSCTL_OUT(req, buf, sizeof(*d));
2156 		if (error)
2157 			break;
2158 	}
2159 	return error;
2160 }
2161 
2162 static int
2163 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
2164 {
2165 	int error;
2166 	char buf[1024];
2167 	struct in6_prefix *p, *pe;
2168 	struct nd_prefix *pr;
2169 
2170 	if (req->newptr)
2171 		return EPERM;
2172 	error = 0;
2173 
2174 	for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
2175 		u_short advrtrs;
2176 		size_t advance;
2177 		struct sockaddr_in6 *sin6, *s6;
2178 		struct nd_pfxrouter *pfr;
2179 
2180 		p = (struct in6_prefix *)buf;
2181 		pe = (struct in6_prefix *)(buf + sizeof(buf));
2182 
2183 		if (p + 1 <= pe) {
2184 			bzero(p, sizeof(*p));
2185 			sin6 = (struct sockaddr_in6 *)(p + 1);
2186 
2187 			p->prefix = pr->ndpr_prefix;
2188 			if (in6_recoverscope(&p->prefix,
2189 			    &p->prefix.sin6_addr, pr->ndpr_ifp) != 0)
2190 				log(LOG_ERR,
2191 				    "scope error in prefix list (%s)\n",
2192 				    ip6_sprintf(&p->prefix.sin6_addr));
2193 			p->raflags = pr->ndpr_raf;
2194 			p->prefixlen = pr->ndpr_plen;
2195 			p->vltime = pr->ndpr_vltime;
2196 			p->pltime = pr->ndpr_pltime;
2197 			p->if_index = pr->ndpr_ifp->if_index;
2198 			p->expire = pr->ndpr_expire;
2199 			p->refcnt = pr->ndpr_refcnt;
2200 			p->flags = pr->ndpr_stateflags;
2201 			p->origin = PR_ORIG_RA;
2202 			advrtrs = 0;
2203 			for (pfr = pr->ndpr_advrtrs.lh_first;
2204 			     pfr;
2205 			     pfr = pfr->pfr_next) {
2206 				if ((void *)&sin6[advrtrs + 1] >
2207 				    (void *)pe) {
2208 					advrtrs++;
2209 					continue;
2210 				}
2211 				s6 = &sin6[advrtrs];
2212 				bzero(s6, sizeof(*s6));
2213 				s6->sin6_family = AF_INET6;
2214 				s6->sin6_len = sizeof(*sin6);
2215 				if (in6_recoverscope(s6, &pfr->router->rtaddr,
2216 						     pfr->router->ifp) != 0)
2217 					log(LOG_ERR,
2218 					    "scope error in "
2219 					    "prefix list (%s)\n",
2220 					    ip6_sprintf(&pfr->router->rtaddr));
2221 				advrtrs++;
2222 			}
2223 			p->advrtrs = advrtrs;
2224 		} else
2225 			panic("buffer too short");
2226 
2227 		advance = sizeof(*p) + sizeof(*sin6) * advrtrs;
2228 		error = SYSCTL_OUT(req, buf, advance);
2229 		if (error)
2230 			break;
2231 	}
2232 	return error;
2233 }
2234