xref: /freebsd/sys/netinet6/nd6.c (revision 9fc5c47fa5c7fa58d61245f0408611943e613164)
1 /*-
2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	$KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/callout.h>
41 #include <sys/malloc.h>
42 #include <sys/mbuf.h>
43 #include <sys/socket.h>
44 #include <sys/sockio.h>
45 #include <sys/time.h>
46 #include <sys/kernel.h>
47 #include <sys/protosw.h>
48 #include <sys/errno.h>
49 #include <sys/syslog.h>
50 #include <sys/lock.h>
51 #include <sys/rwlock.h>
52 #include <sys/queue.h>
53 #include <sys/sdt.h>
54 #include <sys/sysctl.h>
55 
56 #include <net/if.h>
57 #include <net/if_var.h>
58 #include <net/if_arc.h>
59 #include <net/if_dl.h>
60 #include <net/if_types.h>
61 #include <net/iso88025.h>
62 #include <net/fddi.h>
63 #include <net/route.h>
64 #include <net/vnet.h>
65 
66 #include <netinet/in.h>
67 #include <netinet/in_kdtrace.h>
68 #include <net/if_llatbl.h>
69 #include <netinet/if_ether.h>
70 #include <netinet6/in6_var.h>
71 #include <netinet/ip6.h>
72 #include <netinet6/ip6_var.h>
73 #include <netinet6/scope6_var.h>
74 #include <netinet6/nd6.h>
75 #include <netinet6/in6_ifattach.h>
76 #include <netinet/icmp6.h>
77 #include <netinet6/send.h>
78 
79 #include <sys/limits.h>
80 
81 #include <security/mac/mac_framework.h>
82 
83 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
84 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
85 
86 #define SIN6(s) ((const struct sockaddr_in6 *)(s))
87 
88 /* timer values */
89 VNET_DEFINE(int, nd6_prune)	= 1;	/* walk list every 1 seconds */
90 VNET_DEFINE(int, nd6_delay)	= 5;	/* delay first probe time 5 second */
91 VNET_DEFINE(int, nd6_umaxtries)	= 3;	/* maximum unicast query */
92 VNET_DEFINE(int, nd6_mmaxtries)	= 3;	/* maximum multicast query */
93 VNET_DEFINE(int, nd6_useloopback) = 1;	/* use loopback interface for
94 					 * local traffic */
95 VNET_DEFINE(int, nd6_gctimer)	= (60 * 60 * 24); /* 1 day: garbage
96 					 * collection timer */
97 
98 /* preventing too many loops in ND option parsing */
99 static VNET_DEFINE(int, nd6_maxndopt) = 10; /* max # of ND options allowed */
100 
101 VNET_DEFINE(int, nd6_maxnudhint) = 0;	/* max # of subsequent upper
102 					 * layer hints */
103 static VNET_DEFINE(int, nd6_maxqueuelen) = 1; /* max pkts cached in unresolved
104 					 * ND entries */
105 #define	V_nd6_maxndopt			VNET(nd6_maxndopt)
106 #define	V_nd6_maxqueuelen		VNET(nd6_maxqueuelen)
107 
108 #ifdef ND6_DEBUG
109 VNET_DEFINE(int, nd6_debug) = 1;
110 #else
111 VNET_DEFINE(int, nd6_debug) = 0;
112 #endif
113 
114 static eventhandler_tag lle_event_eh;
115 
116 /* for debugging? */
117 #if 0
118 static int nd6_inuse, nd6_allocated;
119 #endif
120 
121 VNET_DEFINE(struct nd_drhead, nd_defrouter);
122 VNET_DEFINE(struct nd_prhead, nd_prefix);
123 
124 VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL;
125 #define	V_nd6_recalc_reachtm_interval	VNET(nd6_recalc_reachtm_interval)
126 
127 int	(*send_sendso_input_hook)(struct mbuf *, struct ifnet *, int, int);
128 
129 static int nd6_is_new_addr_neighbor(struct sockaddr_in6 *,
130 	struct ifnet *);
131 static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *);
132 static void nd6_slowtimo(void *);
133 static int regen_tmpaddr(struct in6_ifaddr *);
134 static struct llentry *nd6_free(struct llentry *, int);
135 static void nd6_llinfo_timer(void *);
136 static void clear_llinfo_pqueue(struct llentry *);
137 static void nd6_rtrequest(int, struct rtentry *, struct rt_addrinfo *);
138 static int nd6_output_lle(struct ifnet *, struct ifnet *, struct mbuf *,
139 	struct sockaddr_in6 *);
140 static int nd6_output_ifp(struct ifnet *, struct ifnet *, struct mbuf *,
141     struct sockaddr_in6 *);
142 
143 static VNET_DEFINE(struct callout, nd6_slowtimo_ch);
144 #define	V_nd6_slowtimo_ch		VNET(nd6_slowtimo_ch)
145 
146 VNET_DEFINE(struct callout, nd6_timer_ch);
147 
148 static void
149 nd6_lle_event(void *arg __unused, struct llentry *lle, int evt)
150 {
151 	struct rt_addrinfo rtinfo;
152 	struct sockaddr_in6 dst;
153 	struct sockaddr_dl gw;
154 	struct ifnet *ifp;
155 	int type;
156 
157 	LLE_WLOCK_ASSERT(lle);
158 
159 	if (lltable_get_af(lle->lle_tbl) != AF_INET6)
160 		return;
161 
162 	switch (evt) {
163 	case LLENTRY_RESOLVED:
164 		type = RTM_ADD;
165 		KASSERT(lle->la_flags & LLE_VALID,
166 		    ("%s: %p resolved but not valid?", __func__, lle));
167 		break;
168 	case LLENTRY_EXPIRED:
169 		type = RTM_DELETE;
170 		break;
171 	default:
172 		return;
173 	}
174 
175 	ifp = lltable_get_ifp(lle->lle_tbl);
176 
177 	bzero(&dst, sizeof(dst));
178 	bzero(&gw, sizeof(gw));
179 	bzero(&rtinfo, sizeof(rtinfo));
180 	lltable_fill_sa_entry(lle, (struct sockaddr *)&dst);
181 	dst.sin6_scope_id = in6_getscopezone(ifp,
182 	    in6_addrscope(&dst.sin6_addr));
183 	gw.sdl_len = sizeof(struct sockaddr_dl);
184 	gw.sdl_family = AF_LINK;
185 	gw.sdl_alen = ifp->if_addrlen;
186 	gw.sdl_index = ifp->if_index;
187 	gw.sdl_type = ifp->if_type;
188 	if (evt == LLENTRY_RESOLVED)
189 		bcopy(&lle->ll_addr, gw.sdl_data, ifp->if_addrlen);
190 	rtinfo.rti_info[RTAX_DST] = (struct sockaddr *)&dst;
191 	rtinfo.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&gw;
192 	rtinfo.rti_addrs = RTA_DST | RTA_GATEWAY;
193 	rt_missmsg_fib(type, &rtinfo, RTF_HOST | RTF_LLDATA | (
194 	    type == RTM_ADD ? RTF_UP: 0), 0, RT_DEFAULT_FIB);
195 }
196 
197 void
198 nd6_init(void)
199 {
200 
201 	LIST_INIT(&V_nd_prefix);
202 
203 	/* initialization of the default router list */
204 	TAILQ_INIT(&V_nd_defrouter);
205 
206 	/* start timer */
207 	callout_init(&V_nd6_slowtimo_ch, 0);
208 	callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
209 	    nd6_slowtimo, curvnet);
210 
211 	nd6_dad_init();
212 	if (IS_DEFAULT_VNET(curvnet))
213 		lle_event_eh = EVENTHANDLER_REGISTER(lle_event, nd6_lle_event,
214 		    NULL, EVENTHANDLER_PRI_ANY);
215 }
216 
217 #ifdef VIMAGE
218 void
219 nd6_destroy()
220 {
221 
222 	callout_drain(&V_nd6_slowtimo_ch);
223 	callout_drain(&V_nd6_timer_ch);
224 	if (IS_DEFAULT_VNET(curvnet))
225 		EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
226 }
227 #endif
228 
229 struct nd_ifinfo *
230 nd6_ifattach(struct ifnet *ifp)
231 {
232 	struct nd_ifinfo *nd;
233 
234 	nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK|M_ZERO);
235 	nd->initialized = 1;
236 
237 	nd->chlim = IPV6_DEFHLIM;
238 	nd->basereachable = REACHABLE_TIME;
239 	nd->reachable = ND_COMPUTE_RTIME(nd->basereachable);
240 	nd->retrans = RETRANS_TIMER;
241 
242 	nd->flags = ND6_IFF_PERFORMNUD;
243 
244 	/* A loopback interface always has ND6_IFF_AUTO_LINKLOCAL.
245 	 * XXXHRS: Clear ND6_IFF_AUTO_LINKLOCAL on an IFT_BRIDGE interface by
246 	 * default regardless of the V_ip6_auto_linklocal configuration to
247 	 * give a reasonable default behavior.
248 	 */
249 	if ((V_ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) ||
250 	    (ifp->if_flags & IFF_LOOPBACK))
251 		nd->flags |= ND6_IFF_AUTO_LINKLOCAL;
252 	/*
253 	 * A loopback interface does not need to accept RTADV.
254 	 * XXXHRS: Clear ND6_IFF_ACCEPT_RTADV on an IFT_BRIDGE interface by
255 	 * default regardless of the V_ip6_accept_rtadv configuration to
256 	 * prevent the interface from accepting RA messages arrived
257 	 * on one of the member interfaces with ND6_IFF_ACCEPT_RTADV.
258 	 */
259 	if (V_ip6_accept_rtadv &&
260 	    !(ifp->if_flags & IFF_LOOPBACK) &&
261 	    (ifp->if_type != IFT_BRIDGE))
262 			nd->flags |= ND6_IFF_ACCEPT_RTADV;
263 	if (V_ip6_no_radr && !(ifp->if_flags & IFF_LOOPBACK))
264 		nd->flags |= ND6_IFF_NO_RADR;
265 
266 	/* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
267 	nd6_setmtu0(ifp, nd);
268 
269 	return nd;
270 }
271 
272 void
273 nd6_ifdetach(struct nd_ifinfo *nd)
274 {
275 
276 	free(nd, M_IP6NDP);
277 }
278 
279 /*
280  * Reset ND level link MTU. This function is called when the physical MTU
281  * changes, which means we might have to adjust the ND level MTU.
282  */
283 void
284 nd6_setmtu(struct ifnet *ifp)
285 {
286 
287 	nd6_setmtu0(ifp, ND_IFINFO(ifp));
288 }
289 
290 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
291 void
292 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi)
293 {
294 	u_int32_t omaxmtu;
295 
296 	omaxmtu = ndi->maxmtu;
297 
298 	switch (ifp->if_type) {
299 	case IFT_ARCNET:
300 		ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */
301 		break;
302 	case IFT_FDDI:
303 		ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); /* RFC2467 */
304 		break;
305 	case IFT_ISO88025:
306 		 ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu);
307 		 break;
308 	default:
309 		ndi->maxmtu = ifp->if_mtu;
310 		break;
311 	}
312 
313 	/*
314 	 * Decreasing the interface MTU under IPV6 minimum MTU may cause
315 	 * undesirable situation.  We thus notify the operator of the change
316 	 * explicitly.  The check for omaxmtu is necessary to restrict the
317 	 * log to the case of changing the MTU, not initializing it.
318 	 */
319 	if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) {
320 		log(LOG_NOTICE, "nd6_setmtu0: "
321 		    "new link MTU on %s (%lu) is too small for IPv6\n",
322 		    if_name(ifp), (unsigned long)ndi->maxmtu);
323 	}
324 
325 	if (ndi->maxmtu > V_in6_maxmtu)
326 		in6_setmaxmtu(); /* check all interfaces just in case */
327 
328 }
329 
330 void
331 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
332 {
333 
334 	bzero(ndopts, sizeof(*ndopts));
335 	ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
336 	ndopts->nd_opts_last
337 		= (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
338 
339 	if (icmp6len == 0) {
340 		ndopts->nd_opts_done = 1;
341 		ndopts->nd_opts_search = NULL;
342 	}
343 }
344 
345 /*
346  * Take one ND option.
347  */
348 struct nd_opt_hdr *
349 nd6_option(union nd_opts *ndopts)
350 {
351 	struct nd_opt_hdr *nd_opt;
352 	int olen;
353 
354 	KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__));
355 	KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts",
356 	    __func__));
357 	if (ndopts->nd_opts_search == NULL)
358 		return NULL;
359 	if (ndopts->nd_opts_done)
360 		return NULL;
361 
362 	nd_opt = ndopts->nd_opts_search;
363 
364 	/* make sure nd_opt_len is inside the buffer */
365 	if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) {
366 		bzero(ndopts, sizeof(*ndopts));
367 		return NULL;
368 	}
369 
370 	olen = nd_opt->nd_opt_len << 3;
371 	if (olen == 0) {
372 		/*
373 		 * Message validation requires that all included
374 		 * options have a length that is greater than zero.
375 		 */
376 		bzero(ndopts, sizeof(*ndopts));
377 		return NULL;
378 	}
379 
380 	ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen);
381 	if (ndopts->nd_opts_search > ndopts->nd_opts_last) {
382 		/* option overruns the end of buffer, invalid */
383 		bzero(ndopts, sizeof(*ndopts));
384 		return NULL;
385 	} else if (ndopts->nd_opts_search == ndopts->nd_opts_last) {
386 		/* reached the end of options chain */
387 		ndopts->nd_opts_done = 1;
388 		ndopts->nd_opts_search = NULL;
389 	}
390 	return nd_opt;
391 }
392 
393 /*
394  * Parse multiple ND options.
395  * This function is much easier to use, for ND routines that do not need
396  * multiple options of the same type.
397  */
398 int
399 nd6_options(union nd_opts *ndopts)
400 {
401 	struct nd_opt_hdr *nd_opt;
402 	int i = 0;
403 
404 	KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__));
405 	KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts",
406 	    __func__));
407 	if (ndopts->nd_opts_search == NULL)
408 		return 0;
409 
410 	while (1) {
411 		nd_opt = nd6_option(ndopts);
412 		if (nd_opt == NULL && ndopts->nd_opts_last == NULL) {
413 			/*
414 			 * Message validation requires that all included
415 			 * options have a length that is greater than zero.
416 			 */
417 			ICMP6STAT_INC(icp6s_nd_badopt);
418 			bzero(ndopts, sizeof(*ndopts));
419 			return -1;
420 		}
421 
422 		if (nd_opt == NULL)
423 			goto skip1;
424 
425 		switch (nd_opt->nd_opt_type) {
426 		case ND_OPT_SOURCE_LINKADDR:
427 		case ND_OPT_TARGET_LINKADDR:
428 		case ND_OPT_MTU:
429 		case ND_OPT_REDIRECTED_HEADER:
430 		case ND_OPT_NONCE:
431 			if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
432 				nd6log((LOG_INFO,
433 				    "duplicated ND6 option found (type=%d)\n",
434 				    nd_opt->nd_opt_type));
435 				/* XXX bark? */
436 			} else {
437 				ndopts->nd_opt_array[nd_opt->nd_opt_type]
438 					= nd_opt;
439 			}
440 			break;
441 		case ND_OPT_PREFIX_INFORMATION:
442 			if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) {
443 				ndopts->nd_opt_array[nd_opt->nd_opt_type]
444 					= nd_opt;
445 			}
446 			ndopts->nd_opts_pi_end =
447 				(struct nd_opt_prefix_info *)nd_opt;
448 			break;
449 		/* What about ND_OPT_ROUTE_INFO? RFC 4191 */
450 		case ND_OPT_RDNSS:	/* RFC 6106 */
451 		case ND_OPT_DNSSL:	/* RFC 6106 */
452 			/*
453 			 * Silently ignore options we know and do not care about
454 			 * in the kernel.
455 			 */
456 			break;
457 		default:
458 			/*
459 			 * Unknown options must be silently ignored,
460 			 * to accomodate future extension to the protocol.
461 			 */
462 			nd6log((LOG_DEBUG,
463 			    "nd6_options: unsupported option %d - "
464 			    "option ignored\n", nd_opt->nd_opt_type));
465 		}
466 
467 skip1:
468 		i++;
469 		if (i > V_nd6_maxndopt) {
470 			ICMP6STAT_INC(icp6s_nd_toomanyopt);
471 			nd6log((LOG_INFO, "too many loop in nd opt\n"));
472 			break;
473 		}
474 
475 		if (ndopts->nd_opts_done)
476 			break;
477 	}
478 
479 	return 0;
480 }
481 
482 /*
483  * ND6 timer routine to handle ND6 entries
484  */
485 void
486 nd6_llinfo_settimer_locked(struct llentry *ln, long tick)
487 {
488 	int canceled;
489 
490 	LLE_WLOCK_ASSERT(ln);
491 
492 	if (tick < 0) {
493 		ln->la_expire = 0;
494 		ln->ln_ntick = 0;
495 		canceled = callout_stop(&ln->lle_timer);
496 	} else {
497 		ln->la_expire = time_uptime + tick / hz;
498 		LLE_ADDREF(ln);
499 		if (tick > INT_MAX) {
500 			ln->ln_ntick = tick - INT_MAX;
501 			canceled = callout_reset(&ln->lle_timer, INT_MAX,
502 			    nd6_llinfo_timer, ln);
503 		} else {
504 			ln->ln_ntick = 0;
505 			canceled = callout_reset(&ln->lle_timer, tick,
506 			    nd6_llinfo_timer, ln);
507 		}
508 	}
509 	if (canceled)
510 		LLE_REMREF(ln);
511 }
512 
513 void
514 nd6_llinfo_settimer(struct llentry *ln, long tick)
515 {
516 
517 	LLE_WLOCK(ln);
518 	nd6_llinfo_settimer_locked(ln, tick);
519 	LLE_WUNLOCK(ln);
520 }
521 
522 static void
523 nd6_llinfo_timer(void *arg)
524 {
525 	struct llentry *ln;
526 	struct in6_addr *dst;
527 	struct ifnet *ifp;
528 	struct nd_ifinfo *ndi = NULL;
529 
530 	KASSERT(arg != NULL, ("%s: arg NULL", __func__));
531 	ln = (struct llentry *)arg;
532 	LLE_WLOCK(ln);
533 	if (callout_pending(&ln->lle_timer)) {
534 		/*
535 		 * Here we are a bit odd here in the treatment of
536 		 * active/pending. If the pending bit is set, it got
537 		 * rescheduled before I ran. The active
538 		 * bit we ignore, since if it was stopped
539 		 * in ll_tablefree() and was currently running
540 		 * it would have return 0 so the code would
541 		 * not have deleted it since the callout could
542 		 * not be stopped so we want to go through
543 		 * with the delete here now. If the callout
544 		 * was restarted, the pending bit will be back on and
545 		 * we just want to bail since the callout_reset would
546 		 * return 1 and our reference would have been removed
547 		 * by nd6_llinfo_settimer_locked above since canceled
548 		 * would have been 1.
549 		 */
550 		LLE_WUNLOCK(ln);
551 		return;
552 	}
553 	ifp = ln->lle_tbl->llt_ifp;
554 	CURVNET_SET(ifp->if_vnet);
555 
556 	if (ln->ln_ntick > 0) {
557 		if (ln->ln_ntick > INT_MAX) {
558 			ln->ln_ntick -= INT_MAX;
559 			nd6_llinfo_settimer_locked(ln, INT_MAX);
560 		} else {
561 			ln->ln_ntick = 0;
562 			nd6_llinfo_settimer_locked(ln, ln->ln_ntick);
563 		}
564 		goto done;
565 	}
566 
567 	ndi = ND_IFINFO(ifp);
568 	dst = &ln->r_l3addr.addr6;
569 	if (ln->la_flags & LLE_STATIC) {
570 		goto done;
571 	}
572 
573 	if (ln->la_flags & LLE_DELETED) {
574 		(void)nd6_free(ln, 0);
575 		ln = NULL;
576 		goto done;
577 	}
578 
579 	switch (ln->ln_state) {
580 	case ND6_LLINFO_INCOMPLETE:
581 		if (ln->la_asked < V_nd6_mmaxtries) {
582 			ln->la_asked++;
583 			nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
584 			LLE_WUNLOCK(ln);
585 			nd6_ns_output(ifp, NULL, dst, ln, NULL);
586 			LLE_WLOCK(ln);
587 		} else {
588 			struct mbuf *m = ln->la_hold;
589 			if (m) {
590 				struct mbuf *m0;
591 
592 				/*
593 				 * assuming every packet in la_hold has the
594 				 * same IP header.  Send error after unlock.
595 				 */
596 				m0 = m->m_nextpkt;
597 				m->m_nextpkt = NULL;
598 				ln->la_hold = m0;
599 				clear_llinfo_pqueue(ln);
600 			}
601 			EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_TIMEDOUT);
602 			(void)nd6_free(ln, 0);
603 			ln = NULL;
604 			if (m != NULL)
605 				icmp6_error2(m, ICMP6_DST_UNREACH,
606 				    ICMP6_DST_UNREACH_ADDR, 0, ifp);
607 		}
608 		break;
609 	case ND6_LLINFO_REACHABLE:
610 		if (!ND6_LLINFO_PERMANENT(ln)) {
611 			ln->ln_state = ND6_LLINFO_STALE;
612 			nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
613 		}
614 		break;
615 
616 	case ND6_LLINFO_STALE:
617 		/* Garbage Collection(RFC 2461 5.3) */
618 		if (!ND6_LLINFO_PERMANENT(ln)) {
619 			EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED);
620 			(void)nd6_free(ln, 1);
621 			ln = NULL;
622 		}
623 		break;
624 
625 	case ND6_LLINFO_DELAY:
626 		if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) {
627 			/* We need NUD */
628 			ln->la_asked = 1;
629 			ln->ln_state = ND6_LLINFO_PROBE;
630 			nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
631 			LLE_WUNLOCK(ln);
632 			nd6_ns_output(ifp, dst, dst, ln, NULL);
633 			LLE_WLOCK(ln);
634 		} else {
635 			ln->ln_state = ND6_LLINFO_STALE; /* XXX */
636 			nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
637 		}
638 		break;
639 	case ND6_LLINFO_PROBE:
640 		if (ln->la_asked < V_nd6_umaxtries) {
641 			ln->la_asked++;
642 			nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
643 			LLE_WUNLOCK(ln);
644 			nd6_ns_output(ifp, dst, dst, ln, NULL);
645 			LLE_WLOCK(ln);
646 		} else {
647 			EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED);
648 			(void)nd6_free(ln, 0);
649 			ln = NULL;
650 		}
651 		break;
652 	default:
653 		panic("%s: paths in a dark night can be confusing: %d",
654 		    __func__, ln->ln_state);
655 	}
656 done:
657 	if (ln != NULL)
658 		LLE_FREE_LOCKED(ln);
659 	CURVNET_RESTORE();
660 }
661 
662 
663 /*
664  * ND6 timer routine to expire default route list and prefix list
665  */
666 void
667 nd6_timer(void *arg)
668 {
669 	CURVNET_SET((struct vnet *) arg);
670 	struct nd_defrouter *dr, *ndr;
671 	struct nd_prefix *pr, *npr;
672 	struct in6_ifaddr *ia6, *nia6;
673 
674 	callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz,
675 	    nd6_timer, curvnet);
676 
677 	/* expire default router list */
678 	TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
679 		if (dr->expire && dr->expire < time_uptime)
680 			defrtrlist_del(dr);
681 	}
682 
683 	/*
684 	 * expire interface addresses.
685 	 * in the past the loop was inside prefix expiry processing.
686 	 * However, from a stricter speci-confrmance standpoint, we should
687 	 * rather separate address lifetimes and prefix lifetimes.
688 	 *
689 	 * XXXRW: in6_ifaddrhead locking.
690 	 */
691   addrloop:
692 	TAILQ_FOREACH_SAFE(ia6, &V_in6_ifaddrhead, ia_link, nia6) {
693 		/* check address lifetime */
694 		if (IFA6_IS_INVALID(ia6)) {
695 			int regen = 0;
696 
697 			/*
698 			 * If the expiring address is temporary, try
699 			 * regenerating a new one.  This would be useful when
700 			 * we suspended a laptop PC, then turned it on after a
701 			 * period that could invalidate all temporary
702 			 * addresses.  Although we may have to restart the
703 			 * loop (see below), it must be after purging the
704 			 * address.  Otherwise, we'd see an infinite loop of
705 			 * regeneration.
706 			 */
707 			if (V_ip6_use_tempaddr &&
708 			    (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
709 				if (regen_tmpaddr(ia6) == 0)
710 					regen = 1;
711 			}
712 
713 			in6_purgeaddr(&ia6->ia_ifa);
714 
715 			if (regen)
716 				goto addrloop; /* XXX: see below */
717 		} else if (IFA6_IS_DEPRECATED(ia6)) {
718 			int oldflags = ia6->ia6_flags;
719 
720 			ia6->ia6_flags |= IN6_IFF_DEPRECATED;
721 
722 			/*
723 			 * If a temporary address has just become deprecated,
724 			 * regenerate a new one if possible.
725 			 */
726 			if (V_ip6_use_tempaddr &&
727 			    (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
728 			    (oldflags & IN6_IFF_DEPRECATED) == 0) {
729 
730 				if (regen_tmpaddr(ia6) == 0) {
731 					/*
732 					 * A new temporary address is
733 					 * generated.
734 					 * XXX: this means the address chain
735 					 * has changed while we are still in
736 					 * the loop.  Although the change
737 					 * would not cause disaster (because
738 					 * it's not a deletion, but an
739 					 * addition,) we'd rather restart the
740 					 * loop just for safety.  Or does this
741 					 * significantly reduce performance??
742 					 */
743 					goto addrloop;
744 				}
745 			}
746 		} else {
747 			/*
748 			 * A new RA might have made a deprecated address
749 			 * preferred.
750 			 */
751 			ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
752 		}
753 	}
754 
755 	/* expire prefix list */
756 	LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
757 		/*
758 		 * check prefix lifetime.
759 		 * since pltime is just for autoconf, pltime processing for
760 		 * prefix is not necessary.
761 		 */
762 		if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME &&
763 		    time_uptime - pr->ndpr_lastupdate > pr->ndpr_vltime) {
764 
765 			/*
766 			 * address expiration and prefix expiration are
767 			 * separate.  NEVER perform in6_purgeaddr here.
768 			 */
769 			prelist_remove(pr);
770 		}
771 	}
772 	CURVNET_RESTORE();
773 }
774 
775 /*
776  * ia6 - deprecated/invalidated temporary address
777  */
778 static int
779 regen_tmpaddr(struct in6_ifaddr *ia6)
780 {
781 	struct ifaddr *ifa;
782 	struct ifnet *ifp;
783 	struct in6_ifaddr *public_ifa6 = NULL;
784 
785 	ifp = ia6->ia_ifa.ifa_ifp;
786 	IF_ADDR_RLOCK(ifp);
787 	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
788 		struct in6_ifaddr *it6;
789 
790 		if (ifa->ifa_addr->sa_family != AF_INET6)
791 			continue;
792 
793 		it6 = (struct in6_ifaddr *)ifa;
794 
795 		/* ignore no autoconf addresses. */
796 		if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0)
797 			continue;
798 
799 		/* ignore autoconf addresses with different prefixes. */
800 		if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
801 			continue;
802 
803 		/*
804 		 * Now we are looking at an autoconf address with the same
805 		 * prefix as ours.  If the address is temporary and is still
806 		 * preferred, do not create another one.  It would be rare, but
807 		 * could happen, for example, when we resume a laptop PC after
808 		 * a long period.
809 		 */
810 		if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
811 		    !IFA6_IS_DEPRECATED(it6)) {
812 			public_ifa6 = NULL;
813 			break;
814 		}
815 
816 		/*
817 		 * This is a public autoconf address that has the same prefix
818 		 * as ours.  If it is preferred, keep it.  We can't break the
819 		 * loop here, because there may be a still-preferred temporary
820 		 * address with the prefix.
821 		 */
822 		if (!IFA6_IS_DEPRECATED(it6))
823 			public_ifa6 = it6;
824 	}
825 	if (public_ifa6 != NULL)
826 		ifa_ref(&public_ifa6->ia_ifa);
827 	IF_ADDR_RUNLOCK(ifp);
828 
829 	if (public_ifa6 != NULL) {
830 		int e;
831 
832 		if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) {
833 			ifa_free(&public_ifa6->ia_ifa);
834 			log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
835 			    " tmp addr,errno=%d\n", e);
836 			return (-1);
837 		}
838 		ifa_free(&public_ifa6->ia_ifa);
839 		return (0);
840 	}
841 
842 	return (-1);
843 }
844 
845 /*
846  * Nuke neighbor cache/prefix/default router management table, right before
847  * ifp goes away.
848  */
849 void
850 nd6_purge(struct ifnet *ifp)
851 {
852 	struct nd_defrouter *dr, *ndr;
853 	struct nd_prefix *pr, *npr;
854 
855 	/*
856 	 * Nuke default router list entries toward ifp.
857 	 * We defer removal of default router list entries that is installed
858 	 * in the routing table, in order to keep additional side effects as
859 	 * small as possible.
860 	 */
861 	TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
862 		if (dr->installed)
863 			continue;
864 
865 		if (dr->ifp == ifp)
866 			defrtrlist_del(dr);
867 	}
868 
869 	TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
870 		if (!dr->installed)
871 			continue;
872 
873 		if (dr->ifp == ifp)
874 			defrtrlist_del(dr);
875 	}
876 
877 	/* Nuke prefix list entries toward ifp */
878 	LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
879 		if (pr->ndpr_ifp == ifp) {
880 			/*
881 			 * Because if_detach() does *not* release prefixes
882 			 * while purging addresses the reference count will
883 			 * still be above zero. We therefore reset it to
884 			 * make sure that the prefix really gets purged.
885 			 */
886 			pr->ndpr_refcnt = 0;
887 
888 			/*
889 			 * Previously, pr->ndpr_addr is removed as well,
890 			 * but I strongly believe we don't have to do it.
891 			 * nd6_purge() is only called from in6_ifdetach(),
892 			 * which removes all the associated interface addresses
893 			 * by itself.
894 			 * (jinmei@kame.net 20010129)
895 			 */
896 			prelist_remove(pr);
897 		}
898 	}
899 
900 	/* cancel default outgoing interface setting */
901 	if (V_nd6_defifindex == ifp->if_index)
902 		nd6_setdefaultiface(0);
903 
904 	if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
905 		/* Refresh default router list. */
906 		defrouter_select();
907 	}
908 
909 	/* XXXXX
910 	 * We do not nuke the neighbor cache entries here any more
911 	 * because the neighbor cache is kept in if_afdata[AF_INET6].
912 	 * nd6_purge() is invoked by in6_ifdetach() which is called
913 	 * from if_detach() where everything gets purged. So let
914 	 * in6_domifdetach() do the actual L2 table purging work.
915 	 */
916 }
917 
918 /*
919  * the caller acquires and releases the lock on the lltbls
920  * Returns the llentry locked
921  */
922 struct llentry *
923 nd6_lookup(struct in6_addr *addr6, int flags, struct ifnet *ifp)
924 {
925 	struct sockaddr_in6 sin6;
926 	struct llentry *ln;
927 	int llflags;
928 
929 	bzero(&sin6, sizeof(sin6));
930 	sin6.sin6_len = sizeof(struct sockaddr_in6);
931 	sin6.sin6_family = AF_INET6;
932 	sin6.sin6_addr = *addr6;
933 
934 	IF_AFDATA_LOCK_ASSERT(ifp);
935 
936 	llflags = (flags & ND6_EXCLUSIVE) ? LLE_EXCLUSIVE : 0;
937 	ln = lla_lookup(LLTABLE6(ifp), llflags, (struct sockaddr *)&sin6);
938 
939 	return (ln);
940 }
941 
942 struct llentry *
943 nd6_alloc(struct in6_addr *addr6, int flags, struct ifnet *ifp)
944 {
945 	struct sockaddr_in6 sin6;
946 	struct llentry *ln;
947 
948 	bzero(&sin6, sizeof(sin6));
949 	sin6.sin6_len = sizeof(struct sockaddr_in6);
950 	sin6.sin6_family = AF_INET6;
951 	sin6.sin6_addr = *addr6;
952 
953 	ln = lltable_alloc_entry(LLTABLE6(ifp), 0, (struct sockaddr *)&sin6);
954 	if (ln != NULL)
955 		ln->ln_state = ND6_LLINFO_NOSTATE;
956 
957 	return (ln);
958 }
959 
960 /*
961  * Test whether a given IPv6 address is a neighbor or not, ignoring
962  * the actual neighbor cache.  The neighbor cache is ignored in order
963  * to not reenter the routing code from within itself.
964  */
965 static int
966 nd6_is_new_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
967 {
968 	struct nd_prefix *pr;
969 	struct ifaddr *dstaddr;
970 
971 	/*
972 	 * A link-local address is always a neighbor.
973 	 * XXX: a link does not necessarily specify a single interface.
974 	 */
975 	if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) {
976 		struct sockaddr_in6 sin6_copy;
977 		u_int32_t zone;
978 
979 		/*
980 		 * We need sin6_copy since sa6_recoverscope() may modify the
981 		 * content (XXX).
982 		 */
983 		sin6_copy = *addr;
984 		if (sa6_recoverscope(&sin6_copy))
985 			return (0); /* XXX: should be impossible */
986 		if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone))
987 			return (0);
988 		if (sin6_copy.sin6_scope_id == zone)
989 			return (1);
990 		else
991 			return (0);
992 	}
993 
994 	/*
995 	 * If the address matches one of our addresses,
996 	 * it should be a neighbor.
997 	 * If the address matches one of our on-link prefixes, it should be a
998 	 * neighbor.
999 	 */
1000 	LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1001 		if (pr->ndpr_ifp != ifp)
1002 			continue;
1003 
1004 		if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) {
1005 			struct rtentry *rt;
1006 
1007 			/* Always use the default FIB here. */
1008 			rt = in6_rtalloc1((struct sockaddr *)&pr->ndpr_prefix,
1009 			    0, 0, RT_DEFAULT_FIB);
1010 			if (rt == NULL)
1011 				continue;
1012 			/*
1013 			 * This is the case where multiple interfaces
1014 			 * have the same prefix, but only one is installed
1015 			 * into the routing table and that prefix entry
1016 			 * is not the one being examined here. In the case
1017 			 * where RADIX_MPATH is enabled, multiple route
1018 			 * entries (of the same rt_key value) will be
1019 			 * installed because the interface addresses all
1020 			 * differ.
1021 			 */
1022 			if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
1023 			       &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr)) {
1024 				RTFREE_LOCKED(rt);
1025 				continue;
1026 			}
1027 			RTFREE_LOCKED(rt);
1028 		}
1029 
1030 		if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
1031 		    &addr->sin6_addr, &pr->ndpr_mask))
1032 			return (1);
1033 	}
1034 
1035 	/*
1036 	 * If the address is assigned on the node of the other side of
1037 	 * a p2p interface, the address should be a neighbor.
1038 	 */
1039 	dstaddr = ifa_ifwithdstaddr((struct sockaddr *)addr, RT_ALL_FIBS);
1040 	if (dstaddr != NULL) {
1041 		if (dstaddr->ifa_ifp == ifp) {
1042 			ifa_free(dstaddr);
1043 			return (1);
1044 		}
1045 		ifa_free(dstaddr);
1046 	}
1047 
1048 	/*
1049 	 * If the default router list is empty, all addresses are regarded
1050 	 * as on-link, and thus, as a neighbor.
1051 	 */
1052 	if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV &&
1053 	    TAILQ_EMPTY(&V_nd_defrouter) &&
1054 	    V_nd6_defifindex == ifp->if_index) {
1055 		return (1);
1056 	}
1057 
1058 	return (0);
1059 }
1060 
1061 
1062 /*
1063  * Detect if a given IPv6 address identifies a neighbor on a given link.
1064  * XXX: should take care of the destination of a p2p link?
1065  */
1066 int
1067 nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
1068 {
1069 	struct llentry *lle;
1070 	int rc = 0;
1071 
1072 	IF_AFDATA_UNLOCK_ASSERT(ifp);
1073 	if (nd6_is_new_addr_neighbor(addr, ifp))
1074 		return (1);
1075 
1076 	/*
1077 	 * Even if the address matches none of our addresses, it might be
1078 	 * in the neighbor cache.
1079 	 */
1080 	IF_AFDATA_RLOCK(ifp);
1081 	if ((lle = nd6_lookup(&addr->sin6_addr, 0, ifp)) != NULL) {
1082 		LLE_RUNLOCK(lle);
1083 		rc = 1;
1084 	}
1085 	IF_AFDATA_RUNLOCK(ifp);
1086 	return (rc);
1087 }
1088 
1089 /*
1090  * Free an nd6 llinfo entry.
1091  * Since the function would cause significant changes in the kernel, DO NOT
1092  * make it global, unless you have a strong reason for the change, and are sure
1093  * that the change is safe.
1094  */
1095 static struct llentry *
1096 nd6_free(struct llentry *ln, int gc)
1097 {
1098         struct llentry *next;
1099 	struct nd_defrouter *dr;
1100 	struct ifnet *ifp;
1101 
1102 	LLE_WLOCK_ASSERT(ln);
1103 
1104 	/*
1105 	 * we used to have pfctlinput(PRC_HOSTDEAD) here.
1106 	 * even though it is not harmful, it was not really necessary.
1107 	 */
1108 
1109 	/* cancel timer */
1110 	nd6_llinfo_settimer_locked(ln, -1);
1111 
1112 	ifp = ln->lle_tbl->llt_ifp;
1113 
1114 	if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
1115 		dr = defrouter_lookup(&ln->r_l3addr.addr6, ifp);
1116 
1117 		if (dr != NULL && dr->expire &&
1118 		    ln->ln_state == ND6_LLINFO_STALE && gc) {
1119 			/*
1120 			 * If the reason for the deletion is just garbage
1121 			 * collection, and the neighbor is an active default
1122 			 * router, do not delete it.  Instead, reset the GC
1123 			 * timer using the router's lifetime.
1124 			 * Simply deleting the entry would affect default
1125 			 * router selection, which is not necessarily a good
1126 			 * thing, especially when we're using router preference
1127 			 * values.
1128 			 * XXX: the check for ln_state would be redundant,
1129 			 *      but we intentionally keep it just in case.
1130 			 */
1131 			if (dr->expire > time_uptime)
1132 				nd6_llinfo_settimer_locked(ln,
1133 				    (dr->expire - time_uptime) * hz);
1134 			else
1135 				nd6_llinfo_settimer_locked(ln,
1136 				    (long)V_nd6_gctimer * hz);
1137 
1138 			next = LIST_NEXT(ln, lle_next);
1139 			LLE_REMREF(ln);
1140 			LLE_WUNLOCK(ln);
1141 			return (next);
1142 		}
1143 
1144 		if (dr) {
1145 			/*
1146 			 * Unreachablity of a router might affect the default
1147 			 * router selection and on-link detection of advertised
1148 			 * prefixes.
1149 			 */
1150 
1151 			/*
1152 			 * Temporarily fake the state to choose a new default
1153 			 * router and to perform on-link determination of
1154 			 * prefixes correctly.
1155 			 * Below the state will be set correctly,
1156 			 * or the entry itself will be deleted.
1157 			 */
1158 			ln->ln_state = ND6_LLINFO_INCOMPLETE;
1159 		}
1160 
1161 		if (ln->ln_router || dr) {
1162 
1163 			/*
1164 			 * We need to unlock to avoid a LOR with rt6_flush() with the
1165 			 * rnh and for the calls to pfxlist_onlink_check() and
1166 			 * defrouter_select() in the block further down for calls
1167 			 * into nd6_lookup().  We still hold a ref.
1168 			 */
1169 			LLE_WUNLOCK(ln);
1170 
1171 			/*
1172 			 * rt6_flush must be called whether or not the neighbor
1173 			 * is in the Default Router List.
1174 			 * See a corresponding comment in nd6_na_input().
1175 			 */
1176 			rt6_flush(&ln->r_l3addr.addr6, ifp);
1177 		}
1178 
1179 		if (dr) {
1180 			/*
1181 			 * Since defrouter_select() does not affect the
1182 			 * on-link determination and MIP6 needs the check
1183 			 * before the default router selection, we perform
1184 			 * the check now.
1185 			 */
1186 			pfxlist_onlink_check();
1187 
1188 			/*
1189 			 * Refresh default router list.
1190 			 */
1191 			defrouter_select();
1192 		}
1193 
1194 		if (ln->ln_router || dr)
1195 			LLE_WLOCK(ln);
1196 	}
1197 
1198 	/*
1199 	 * Before deleting the entry, remember the next entry as the
1200 	 * return value.  We need this because pfxlist_onlink_check() above
1201 	 * might have freed other entries (particularly the old next entry) as
1202 	 * a side effect (XXX).
1203 	 */
1204 	next = LIST_NEXT(ln, lle_next);
1205 
1206 	/*
1207 	 * Save to unlock. We still hold an extra reference and will not
1208 	 * free(9) in llentry_free() if someone else holds one as well.
1209 	 */
1210 	LLE_WUNLOCK(ln);
1211 	IF_AFDATA_LOCK(ifp);
1212 	LLE_WLOCK(ln);
1213 
1214 	/* Guard against race with other llentry_free(). */
1215 	if (ln->la_flags & LLE_LINKED) {
1216 		LLE_REMREF(ln);
1217 		llentry_free(ln);
1218 	} else
1219 		LLE_FREE_LOCKED(ln);
1220 
1221 	IF_AFDATA_UNLOCK(ifp);
1222 
1223 	return (next);
1224 }
1225 
1226 /*
1227  * Upper-layer reachability hint for Neighbor Unreachability Detection.
1228  *
1229  * XXX cost-effective methods?
1230  */
1231 void
1232 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force)
1233 {
1234 	struct llentry *ln;
1235 	struct ifnet *ifp;
1236 
1237 	if ((dst6 == NULL) || (rt == NULL))
1238 		return;
1239 
1240 	ifp = rt->rt_ifp;
1241 	IF_AFDATA_RLOCK(ifp);
1242 	ln = nd6_lookup(dst6, ND6_EXCLUSIVE, NULL);
1243 	IF_AFDATA_RUNLOCK(ifp);
1244 	if (ln == NULL)
1245 		return;
1246 
1247 	if (ln->ln_state < ND6_LLINFO_REACHABLE)
1248 		goto done;
1249 
1250 	/*
1251 	 * if we get upper-layer reachability confirmation many times,
1252 	 * it is possible we have false information.
1253 	 */
1254 	if (!force) {
1255 		ln->ln_byhint++;
1256 		if (ln->ln_byhint > V_nd6_maxnudhint) {
1257 			goto done;
1258 		}
1259 	}
1260 
1261  	ln->ln_state = ND6_LLINFO_REACHABLE;
1262 	if (!ND6_LLINFO_PERMANENT(ln)) {
1263 		nd6_llinfo_settimer_locked(ln,
1264 		    (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
1265 	}
1266 done:
1267 	LLE_WUNLOCK(ln);
1268 }
1269 
1270 
1271 /*
1272  * Rejuvenate this function for routing operations related
1273  * processing.
1274  */
1275 void
1276 nd6_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
1277 {
1278 	struct sockaddr_in6 *gateway;
1279 	struct nd_defrouter *dr;
1280 	struct ifnet *ifp;
1281 
1282 	gateway = (struct sockaddr_in6 *)rt->rt_gateway;
1283 	ifp = rt->rt_ifp;
1284 
1285 	switch (req) {
1286 	case RTM_ADD:
1287 		break;
1288 
1289 	case RTM_DELETE:
1290 		if (!ifp)
1291 			return;
1292 		/*
1293 		 * Only indirect routes are interesting.
1294 		 */
1295 		if ((rt->rt_flags & RTF_GATEWAY) == 0)
1296 			return;
1297 		/*
1298 		 * check for default route
1299 		 */
1300 		if (IN6_ARE_ADDR_EQUAL(&in6addr_any,
1301 				       &SIN6(rt_key(rt))->sin6_addr)) {
1302 
1303 			dr = defrouter_lookup(&gateway->sin6_addr, ifp);
1304 			if (dr != NULL)
1305 				dr->installed = 0;
1306 		}
1307 		break;
1308 	}
1309 }
1310 
1311 
1312 int
1313 nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
1314 {
1315 	struct in6_drlist *drl = (struct in6_drlist *)data;
1316 	struct in6_oprlist *oprl = (struct in6_oprlist *)data;
1317 	struct in6_ndireq *ndi = (struct in6_ndireq *)data;
1318 	struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
1319 	struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
1320 	struct nd_defrouter *dr;
1321 	struct nd_prefix *pr;
1322 	int i = 0, error = 0;
1323 
1324 	if (ifp->if_afdata[AF_INET6] == NULL)
1325 		return (EPFNOSUPPORT);
1326 	switch (cmd) {
1327 	case SIOCGDRLST_IN6:
1328 		/*
1329 		 * obsolete API, use sysctl under net.inet6.icmp6
1330 		 */
1331 		bzero(drl, sizeof(*drl));
1332 		TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
1333 			if (i >= DRLSTSIZ)
1334 				break;
1335 			drl->defrouter[i].rtaddr = dr->rtaddr;
1336 			in6_clearscope(&drl->defrouter[i].rtaddr);
1337 
1338 			drl->defrouter[i].flags = dr->flags;
1339 			drl->defrouter[i].rtlifetime = dr->rtlifetime;
1340 			drl->defrouter[i].expire = dr->expire +
1341 			    (time_second - time_uptime);
1342 			drl->defrouter[i].if_index = dr->ifp->if_index;
1343 			i++;
1344 		}
1345 		break;
1346 	case SIOCGPRLST_IN6:
1347 		/*
1348 		 * obsolete API, use sysctl under net.inet6.icmp6
1349 		 *
1350 		 * XXX the structure in6_prlist was changed in backward-
1351 		 * incompatible manner.  in6_oprlist is used for SIOCGPRLST_IN6,
1352 		 * in6_prlist is used for nd6_sysctl() - fill_prlist().
1353 		 */
1354 		/*
1355 		 * XXX meaning of fields, especialy "raflags", is very
1356 		 * differnet between RA prefix list and RR/static prefix list.
1357 		 * how about separating ioctls into two?
1358 		 */
1359 		bzero(oprl, sizeof(*oprl));
1360 		LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1361 			struct nd_pfxrouter *pfr;
1362 			int j;
1363 
1364 			if (i >= PRLSTSIZ)
1365 				break;
1366 			oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr;
1367 			oprl->prefix[i].raflags = pr->ndpr_raf;
1368 			oprl->prefix[i].prefixlen = pr->ndpr_plen;
1369 			oprl->prefix[i].vltime = pr->ndpr_vltime;
1370 			oprl->prefix[i].pltime = pr->ndpr_pltime;
1371 			oprl->prefix[i].if_index = pr->ndpr_ifp->if_index;
1372 			if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME)
1373 				oprl->prefix[i].expire = 0;
1374 			else {
1375 				time_t maxexpire;
1376 
1377 				/* XXX: we assume time_t is signed. */
1378 				maxexpire = (-1) &
1379 				    ~((time_t)1 <<
1380 				    ((sizeof(maxexpire) * 8) - 1));
1381 				if (pr->ndpr_vltime <
1382 				    maxexpire - pr->ndpr_lastupdate) {
1383 					oprl->prefix[i].expire =
1384 					    pr->ndpr_lastupdate +
1385 					    pr->ndpr_vltime +
1386 					    (time_second - time_uptime);
1387 				} else
1388 					oprl->prefix[i].expire = maxexpire;
1389 			}
1390 
1391 			j = 0;
1392 			LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) {
1393 				if (j < DRLSTSIZ) {
1394 #define RTRADDR oprl->prefix[i].advrtr[j]
1395 					RTRADDR = pfr->router->rtaddr;
1396 					in6_clearscope(&RTRADDR);
1397 #undef RTRADDR
1398 				}
1399 				j++;
1400 			}
1401 			oprl->prefix[i].advrtrs = j;
1402 			oprl->prefix[i].origin = PR_ORIG_RA;
1403 
1404 			i++;
1405 		}
1406 
1407 		break;
1408 	case OSIOCGIFINFO_IN6:
1409 #define ND	ndi->ndi
1410 		/* XXX: old ndp(8) assumes a positive value for linkmtu. */
1411 		bzero(&ND, sizeof(ND));
1412 		ND.linkmtu = IN6_LINKMTU(ifp);
1413 		ND.maxmtu = ND_IFINFO(ifp)->maxmtu;
1414 		ND.basereachable = ND_IFINFO(ifp)->basereachable;
1415 		ND.reachable = ND_IFINFO(ifp)->reachable;
1416 		ND.retrans = ND_IFINFO(ifp)->retrans;
1417 		ND.flags = ND_IFINFO(ifp)->flags;
1418 		ND.recalctm = ND_IFINFO(ifp)->recalctm;
1419 		ND.chlim = ND_IFINFO(ifp)->chlim;
1420 		break;
1421 	case SIOCGIFINFO_IN6:
1422 		ND = *ND_IFINFO(ifp);
1423 		break;
1424 	case SIOCSIFINFO_IN6:
1425 		/*
1426 		 * used to change host variables from userland.
1427 		 * intented for a use on router to reflect RA configurations.
1428 		 */
1429 		/* 0 means 'unspecified' */
1430 		if (ND.linkmtu != 0) {
1431 			if (ND.linkmtu < IPV6_MMTU ||
1432 			    ND.linkmtu > IN6_LINKMTU(ifp)) {
1433 				error = EINVAL;
1434 				break;
1435 			}
1436 			ND_IFINFO(ifp)->linkmtu = ND.linkmtu;
1437 		}
1438 
1439 		if (ND.basereachable != 0) {
1440 			int obasereachable = ND_IFINFO(ifp)->basereachable;
1441 
1442 			ND_IFINFO(ifp)->basereachable = ND.basereachable;
1443 			if (ND.basereachable != obasereachable)
1444 				ND_IFINFO(ifp)->reachable =
1445 				    ND_COMPUTE_RTIME(ND.basereachable);
1446 		}
1447 		if (ND.retrans != 0)
1448 			ND_IFINFO(ifp)->retrans = ND.retrans;
1449 		if (ND.chlim != 0)
1450 			ND_IFINFO(ifp)->chlim = ND.chlim;
1451 		/* FALLTHROUGH */
1452 	case SIOCSIFINFO_FLAGS:
1453 	{
1454 		struct ifaddr *ifa;
1455 		struct in6_ifaddr *ia;
1456 
1457 		if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
1458 		    !(ND.flags & ND6_IFF_IFDISABLED)) {
1459 			/* ifdisabled 1->0 transision */
1460 
1461 			/*
1462 			 * If the interface is marked as ND6_IFF_IFDISABLED and
1463 			 * has an link-local address with IN6_IFF_DUPLICATED,
1464 			 * do not clear ND6_IFF_IFDISABLED.
1465 			 * See RFC 4862, Section 5.4.5.
1466 			 */
1467 			int duplicated_linklocal = 0;
1468 
1469 			IF_ADDR_RLOCK(ifp);
1470 			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1471 				if (ifa->ifa_addr->sa_family != AF_INET6)
1472 					continue;
1473 				ia = (struct in6_ifaddr *)ifa;
1474 				if ((ia->ia6_flags & IN6_IFF_DUPLICATED) &&
1475 				    IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) {
1476 					duplicated_linklocal = 1;
1477 					break;
1478 				}
1479 			}
1480 			IF_ADDR_RUNLOCK(ifp);
1481 
1482 			if (duplicated_linklocal) {
1483 				ND.flags |= ND6_IFF_IFDISABLED;
1484 				log(LOG_ERR, "Cannot enable an interface"
1485 				    " with a link-local address marked"
1486 				    " duplicate.\n");
1487 			} else {
1488 				ND_IFINFO(ifp)->flags &= ~ND6_IFF_IFDISABLED;
1489 				if (ifp->if_flags & IFF_UP)
1490 					in6_if_up(ifp);
1491 			}
1492 		} else if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
1493 			    (ND.flags & ND6_IFF_IFDISABLED)) {
1494 			/* ifdisabled 0->1 transision */
1495 			/* Mark all IPv6 address as tentative. */
1496 
1497 			ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1498 			IF_ADDR_RLOCK(ifp);
1499 			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1500 				if (ifa->ifa_addr->sa_family != AF_INET6)
1501 					continue;
1502 				ia = (struct in6_ifaddr *)ifa;
1503 				ia->ia6_flags |= IN6_IFF_TENTATIVE;
1504 			}
1505 			IF_ADDR_RUNLOCK(ifp);
1506 		}
1507 
1508 		if (ND.flags & ND6_IFF_AUTO_LINKLOCAL) {
1509 			if (!(ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL)) {
1510 				/* auto_linklocal 0->1 transision */
1511 
1512 				/* If no link-local address on ifp, configure */
1513 				ND_IFINFO(ifp)->flags |= ND6_IFF_AUTO_LINKLOCAL;
1514 				in6_ifattach(ifp, NULL);
1515 			} else if (!(ND.flags & ND6_IFF_IFDISABLED) &&
1516 			    ifp->if_flags & IFF_UP) {
1517 				/*
1518 				 * When the IF already has
1519 				 * ND6_IFF_AUTO_LINKLOCAL, no link-local
1520 				 * address is assigned, and IFF_UP, try to
1521 				 * assign one.
1522 				 */
1523 				int haslinklocal = 0;
1524 
1525 				IF_ADDR_RLOCK(ifp);
1526 				TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1527 					if (ifa->ifa_addr->sa_family != AF_INET6)
1528 						continue;
1529 					ia = (struct in6_ifaddr *)ifa;
1530 					if (IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) {
1531 						haslinklocal = 1;
1532 						break;
1533 					}
1534 				}
1535 				IF_ADDR_RUNLOCK(ifp);
1536 				if (!haslinklocal)
1537 					in6_ifattach(ifp, NULL);
1538 			}
1539 		}
1540 	}
1541 		ND_IFINFO(ifp)->flags = ND.flags;
1542 		break;
1543 #undef ND
1544 	case SIOCSNDFLUSH_IN6:	/* XXX: the ioctl name is confusing... */
1545 		/* sync kernel routing table with the default router list */
1546 		defrouter_reset();
1547 		defrouter_select();
1548 		break;
1549 	case SIOCSPFXFLUSH_IN6:
1550 	{
1551 		/* flush all the prefix advertised by routers */
1552 		struct nd_prefix *pr, *next;
1553 
1554 		LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) {
1555 			struct in6_ifaddr *ia, *ia_next;
1556 
1557 			if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1558 				continue; /* XXX */
1559 
1560 			/* do we really have to remove addresses as well? */
1561 			/* XXXRW: in6_ifaddrhead locking. */
1562 			TAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link,
1563 			    ia_next) {
1564 				if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1565 					continue;
1566 
1567 				if (ia->ia6_ndpr == pr)
1568 					in6_purgeaddr(&ia->ia_ifa);
1569 			}
1570 			prelist_remove(pr);
1571 		}
1572 		break;
1573 	}
1574 	case SIOCSRTRFLUSH_IN6:
1575 	{
1576 		/* flush all the default routers */
1577 		struct nd_defrouter *dr, *next;
1578 
1579 		defrouter_reset();
1580 		TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, next) {
1581 			defrtrlist_del(dr);
1582 		}
1583 		defrouter_select();
1584 		break;
1585 	}
1586 	case SIOCGNBRINFO_IN6:
1587 	{
1588 		struct llentry *ln;
1589 		struct in6_addr nb_addr = nbi->addr; /* make local for safety */
1590 
1591 		if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0)
1592 			return (error);
1593 
1594 		IF_AFDATA_RLOCK(ifp);
1595 		ln = nd6_lookup(&nb_addr, 0, ifp);
1596 		IF_AFDATA_RUNLOCK(ifp);
1597 
1598 		if (ln == NULL) {
1599 			error = EINVAL;
1600 			break;
1601 		}
1602 		nbi->state = ln->ln_state;
1603 		nbi->asked = ln->la_asked;
1604 		nbi->isrouter = ln->ln_router;
1605 		if (ln->la_expire == 0)
1606 			nbi->expire = 0;
1607 		else
1608 			nbi->expire = ln->la_expire +
1609 			    (time_second - time_uptime);
1610 		LLE_RUNLOCK(ln);
1611 		break;
1612 	}
1613 	case SIOCGDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
1614 		ndif->ifindex = V_nd6_defifindex;
1615 		break;
1616 	case SIOCSDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
1617 		return (nd6_setdefaultiface(ndif->ifindex));
1618 	}
1619 	return (error);
1620 }
1621 
1622 /*
1623  * Create neighbor cache entry and cache link-layer address,
1624  * on reception of inbound ND6 packets.  (RS/RA/NS/redirect)
1625  *
1626  * type - ICMP6 type
1627  * code - type dependent information
1628  *
1629  * XXXXX
1630  *  The caller of this function already acquired the ndp
1631  *  cache table lock because the cache entry is returned.
1632  */
1633 struct llentry *
1634 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr,
1635     int lladdrlen, int type, int code)
1636 {
1637 	struct llentry *ln = NULL, *ln_tmp;
1638 	int is_newentry;
1639 	int do_update;
1640 	int olladdr;
1641 	int llchange;
1642 	int flags;
1643 	int newstate = 0;
1644 	uint16_t router = 0;
1645 	struct sockaddr_in6 sin6;
1646 	struct mbuf *chain = NULL;
1647 	int static_route = 0;
1648 
1649 	IF_AFDATA_UNLOCK_ASSERT(ifp);
1650 
1651 	KASSERT(ifp != NULL, ("%s: ifp == NULL", __func__));
1652 	KASSERT(from != NULL, ("%s: from == NULL", __func__));
1653 
1654 	/* nothing must be updated for unspecified address */
1655 	if (IN6_IS_ADDR_UNSPECIFIED(from))
1656 		return NULL;
1657 
1658 	/*
1659 	 * Validation about ifp->if_addrlen and lladdrlen must be done in
1660 	 * the caller.
1661 	 *
1662 	 * XXX If the link does not have link-layer adderss, what should
1663 	 * we do? (ifp->if_addrlen == 0)
1664 	 * Spec says nothing in sections for RA, RS and NA.  There's small
1665 	 * description on it in NS section (RFC 2461 7.2.3).
1666 	 */
1667 	flags = lladdr ? ND6_EXCLUSIVE : 0;
1668 	IF_AFDATA_RLOCK(ifp);
1669 	ln = nd6_lookup(from, flags, ifp);
1670 	IF_AFDATA_RUNLOCK(ifp);
1671 	is_newentry = 0;
1672 	if (ln == NULL) {
1673 		flags |= ND6_EXCLUSIVE;
1674 		ln = nd6_alloc(from, 0, ifp);
1675 		if (ln == NULL)
1676 			return (NULL);
1677 		IF_AFDATA_WLOCK(ifp);
1678 		LLE_WLOCK(ln);
1679 		/* Prefer any existing lle over newly-created one */
1680 		ln_tmp = nd6_lookup(from, ND6_EXCLUSIVE, ifp);
1681 		if (ln_tmp == NULL)
1682 			lltable_link_entry(LLTABLE6(ifp), ln);
1683 		IF_AFDATA_WUNLOCK(ifp);
1684 		if (ln_tmp == NULL)
1685 			/* No existing lle, mark as new entry */
1686 			is_newentry = 1;
1687 		else {
1688 			lltable_free_entry(LLTABLE6(ifp), ln);
1689 			ln = ln_tmp;
1690 			ln_tmp = NULL;
1691 		}
1692 	}
1693 	/* do nothing if static ndp is set */
1694 	if ((ln->la_flags & LLE_STATIC)) {
1695 			static_route = 1;
1696 			goto done;
1697 	}
1698 
1699 	olladdr = (ln->la_flags & LLE_VALID) ? 1 : 0;
1700 	if (olladdr && lladdr) {
1701 		llchange = bcmp(lladdr, &ln->ll_addr,
1702 		    ifp->if_addrlen);
1703 	} else
1704 		llchange = 0;
1705 
1706 	/*
1707 	 * newentry olladdr  lladdr  llchange	(*=record)
1708 	 *	0	n	n	--	(1)
1709 	 *	0	y	n	--	(2)
1710 	 *	0	n	y	--	(3) * STALE
1711 	 *	0	y	y	n	(4) *
1712 	 *	0	y	y	y	(5) * STALE
1713 	 *	1	--	n	--	(6)   NOSTATE(= PASSIVE)
1714 	 *	1	--	y	--	(7) * STALE
1715 	 */
1716 
1717 	if (lladdr) {		/* (3-5) and (7) */
1718 		/*
1719 		 * Record source link-layer address
1720 		 * XXX is it dependent to ifp->if_type?
1721 		 */
1722 		bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
1723 		ln->la_flags |= LLE_VALID;
1724 		EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED);
1725 	}
1726 
1727 	if (!is_newentry) {
1728 		if ((!olladdr && lladdr != NULL) ||	/* (3) */
1729 		    (olladdr && lladdr != NULL && llchange)) {	/* (5) */
1730 			do_update = 1;
1731 			newstate = ND6_LLINFO_STALE;
1732 		} else					/* (1-2,4) */
1733 			do_update = 0;
1734 	} else {
1735 		do_update = 1;
1736 		if (lladdr == NULL)			/* (6) */
1737 			newstate = ND6_LLINFO_NOSTATE;
1738 		else					/* (7) */
1739 			newstate = ND6_LLINFO_STALE;
1740 	}
1741 
1742 	if (do_update) {
1743 		/*
1744 		 * Update the state of the neighbor cache.
1745 		 */
1746 		ln->ln_state = newstate;
1747 
1748 		if (ln->ln_state == ND6_LLINFO_STALE) {
1749 			if (ln->la_hold != NULL)
1750 				nd6_grab_holdchain(ln, &chain, &sin6);
1751 		} else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
1752 			/* probe right away */
1753 			nd6_llinfo_settimer_locked((void *)ln, 0);
1754 		}
1755 	}
1756 
1757 	/*
1758 	 * ICMP6 type dependent behavior.
1759 	 *
1760 	 * NS: clear IsRouter if new entry
1761 	 * RS: clear IsRouter
1762 	 * RA: set IsRouter if there's lladdr
1763 	 * redir: clear IsRouter if new entry
1764 	 *
1765 	 * RA case, (1):
1766 	 * The spec says that we must set IsRouter in the following cases:
1767 	 * - If lladdr exist, set IsRouter.  This means (1-5).
1768 	 * - If it is old entry (!newentry), set IsRouter.  This means (7).
1769 	 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1770 	 * A quetion arises for (1) case.  (1) case has no lladdr in the
1771 	 * neighbor cache, this is similar to (6).
1772 	 * This case is rare but we figured that we MUST NOT set IsRouter.
1773 	 *
1774 	 * newentry olladdr  lladdr  llchange	    NS  RS  RA	redir
1775 	 *							D R
1776 	 *	0	n	n	--	(1)	c   ?     s
1777 	 *	0	y	n	--	(2)	c   s     s
1778 	 *	0	n	y	--	(3)	c   s     s
1779 	 *	0	y	y	n	(4)	c   s     s
1780 	 *	0	y	y	y	(5)	c   s     s
1781 	 *	1	--	n	--	(6) c	c	c s
1782 	 *	1	--	y	--	(7) c	c   s	c s
1783 	 *
1784 	 *					(c=clear s=set)
1785 	 */
1786 	switch (type & 0xff) {
1787 	case ND_NEIGHBOR_SOLICIT:
1788 		/*
1789 		 * New entry must have is_router flag cleared.
1790 		 */
1791 		if (is_newentry)	/* (6-7) */
1792 			ln->ln_router = 0;
1793 		break;
1794 	case ND_REDIRECT:
1795 		/*
1796 		 * If the icmp is a redirect to a better router, always set the
1797 		 * is_router flag.  Otherwise, if the entry is newly created,
1798 		 * clear the flag.  [RFC 2461, sec 8.3]
1799 		 */
1800 		if (code == ND_REDIRECT_ROUTER)
1801 			ln->ln_router = 1;
1802 		else if (is_newentry) /* (6-7) */
1803 			ln->ln_router = 0;
1804 		break;
1805 	case ND_ROUTER_SOLICIT:
1806 		/*
1807 		 * is_router flag must always be cleared.
1808 		 */
1809 		ln->ln_router = 0;
1810 		break;
1811 	case ND_ROUTER_ADVERT:
1812 		/*
1813 		 * Mark an entry with lladdr as a router.
1814 		 */
1815 		if ((!is_newentry && (olladdr || lladdr)) ||	/* (2-5) */
1816 		    (is_newentry && lladdr)) {			/* (7) */
1817 			ln->ln_router = 1;
1818 		}
1819 		break;
1820 	}
1821 
1822 	if (ln != NULL) {
1823 		static_route = (ln->la_flags & LLE_STATIC);
1824 		router = ln->ln_router;
1825 
1826 		if (flags & ND6_EXCLUSIVE)
1827 			LLE_WUNLOCK(ln);
1828 		else
1829 			LLE_RUNLOCK(ln);
1830 		if (static_route)
1831 			ln = NULL;
1832 	}
1833 	if (chain != NULL)
1834 		nd6_flush_holdchain(ifp, ifp, chain, &sin6);
1835 
1836 	/*
1837 	 * When the link-layer address of a router changes, select the
1838 	 * best router again.  In particular, when the neighbor entry is newly
1839 	 * created, it might affect the selection policy.
1840 	 * Question: can we restrict the first condition to the "is_newentry"
1841 	 * case?
1842 	 * XXX: when we hear an RA from a new router with the link-layer
1843 	 * address option, defrouter_select() is called twice, since
1844 	 * defrtrlist_update called the function as well.  However, I believe
1845 	 * we can compromise the overhead, since it only happens the first
1846 	 * time.
1847 	 * XXX: although defrouter_select() should not have a bad effect
1848 	 * for those are not autoconfigured hosts, we explicitly avoid such
1849 	 * cases for safety.
1850 	 */
1851 	if (do_update && router &&
1852 	    ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
1853 		/*
1854 		 * guaranteed recursion
1855 		 */
1856 		defrouter_select();
1857 	}
1858 
1859 	return (ln);
1860 done:
1861 	if (ln != NULL) {
1862 		if (flags & ND6_EXCLUSIVE)
1863 			LLE_WUNLOCK(ln);
1864 		else
1865 			LLE_RUNLOCK(ln);
1866 		if (static_route)
1867 			ln = NULL;
1868 	}
1869 	return (ln);
1870 }
1871 
1872 static void
1873 nd6_slowtimo(void *arg)
1874 {
1875 	CURVNET_SET((struct vnet *) arg);
1876 	struct nd_ifinfo *nd6if;
1877 	struct ifnet *ifp;
1878 
1879 	callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
1880 	    nd6_slowtimo, curvnet);
1881 	IFNET_RLOCK_NOSLEEP();
1882 	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
1883 		if (ifp->if_afdata[AF_INET6] == NULL)
1884 			continue;
1885 		nd6if = ND_IFINFO(ifp);
1886 		if (nd6if->basereachable && /* already initialized */
1887 		    (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
1888 			/*
1889 			 * Since reachable time rarely changes by router
1890 			 * advertisements, we SHOULD insure that a new random
1891 			 * value gets recomputed at least once every few hours.
1892 			 * (RFC 2461, 6.3.4)
1893 			 */
1894 			nd6if->recalctm = V_nd6_recalc_reachtm_interval;
1895 			nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
1896 		}
1897 	}
1898 	IFNET_RUNLOCK_NOSLEEP();
1899 	CURVNET_RESTORE();
1900 }
1901 
1902 void
1903 nd6_grab_holdchain(struct llentry *ln, struct mbuf **chain,
1904     struct sockaddr_in6 *sin6)
1905 {
1906 
1907 	LLE_WLOCK_ASSERT(ln);
1908 
1909 	*chain = ln->la_hold;
1910 	ln->la_hold = NULL;
1911 	lltable_fill_sa_entry(ln, (struct sockaddr *)sin6);
1912 
1913 	if (ln->ln_state == ND6_LLINFO_STALE) {
1914 
1915 		/*
1916 		 * The first time we send a packet to a
1917 		 * neighbor whose entry is STALE, we have
1918 		 * to change the state to DELAY and a sets
1919 		 * a timer to expire in DELAY_FIRST_PROBE_TIME
1920 		 * seconds to ensure do neighbor unreachability
1921 		 * detection on expiration.
1922 		 * (RFC 2461 7.3.3)
1923 		 */
1924 		ln->la_asked = 0;
1925 		ln->ln_state = ND6_LLINFO_DELAY;
1926 		nd6_llinfo_settimer_locked(ln, (long)V_nd6_delay * hz);
1927 	}
1928 }
1929 
1930 static int
1931 nd6_output_ifp(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1932     struct sockaddr_in6 *dst)
1933 {
1934 	int error;
1935 	int ip6len;
1936 	struct ip6_hdr *ip6;
1937 	struct m_tag *mtag;
1938 
1939 #ifdef MAC
1940 	mac_netinet6_nd6_send(ifp, m);
1941 #endif
1942 
1943 	/*
1944 	 * If called from nd6_ns_output() (NS), nd6_na_output() (NA),
1945 	 * icmp6_redirect_output() (REDIRECT) or from rip6_output() (RS, RA
1946 	 * as handled by rtsol and rtadvd), mbufs will be tagged for SeND
1947 	 * to be diverted to user space.  When re-injected into the kernel,
1948 	 * send_output() will directly dispatch them to the outgoing interface.
1949 	 */
1950 	if (send_sendso_input_hook != NULL) {
1951 		mtag = m_tag_find(m, PACKET_TAG_ND_OUTGOING, NULL);
1952 		if (mtag != NULL) {
1953 			ip6 = mtod(m, struct ip6_hdr *);
1954 			ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
1955 			/* Use the SEND socket */
1956 			error = send_sendso_input_hook(m, ifp, SND_OUT,
1957 			    ip6len);
1958 			/* -1 == no app on SEND socket */
1959 			if (error == 0 || error != -1)
1960 			    return (error);
1961 		}
1962 	}
1963 
1964 	m_clrprotoflags(m);	/* Avoid confusing lower layers. */
1965 	IP_PROBE(send, NULL, NULL, mtod(m, struct ip6_hdr *), ifp, NULL,
1966 	    mtod(m, struct ip6_hdr *));
1967 
1968 	if ((ifp->if_flags & IFF_LOOPBACK) == 0)
1969 		origifp = ifp;
1970 
1971 	error = (*ifp->if_output)(origifp, m, (struct sockaddr *)dst, NULL);
1972 	return (error);
1973 }
1974 
1975 /*
1976  * IPv6 packet output - light version.
1977  * Checks if destination LLE exists and is in proper state
1978  * (e.g no modification required). If not true, fall back to
1979  * "heavy" version.
1980  */
1981 int
1982 nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1983     struct sockaddr_in6 *dst, struct rtentry *rt0)
1984 {
1985 	struct llentry *ln = NULL;
1986 
1987 	/* discard the packet if IPv6 operation is disabled on the interface */
1988 	if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) {
1989 		m_freem(m);
1990 		return (ENETDOWN); /* better error? */
1991 	}
1992 
1993 	if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1994 		goto sendpkt;
1995 
1996 	if (nd6_need_cache(ifp) == 0)
1997 		goto sendpkt;
1998 
1999 	IF_AFDATA_RLOCK(ifp);
2000 	ln = nd6_lookup(&dst->sin6_addr, 0, ifp);
2001 	IF_AFDATA_RUNLOCK(ifp);
2002 
2003 	/*
2004 	 * Perform fast path for the following cases:
2005 	 * 1) lle state is REACHABLE
2006 	 * 2) lle state is DELAY (NS message sentNS message sent)
2007 	 *
2008 	 * Every other case involves lle modification, so we handle
2009 	 * them separately.
2010 	 */
2011 	if (ln == NULL || (ln->ln_state != ND6_LLINFO_REACHABLE &&
2012 	    ln->ln_state != ND6_LLINFO_DELAY)) {
2013 		/* Fall back to slow processing path */
2014 		if (ln != NULL)
2015 			LLE_RUNLOCK(ln);
2016 		return (nd6_output_lle(ifp, origifp, m, dst));
2017 	}
2018 
2019 sendpkt:
2020 	if (ln != NULL)
2021 		LLE_RUNLOCK(ln);
2022 
2023 	return (nd6_output_ifp(ifp, origifp, m, dst));
2024 }
2025 
2026 
2027 /*
2028  * Output IPv6 packet - heavy version.
2029  * Function assume that either
2030  * 1) destination LLE does not exist, is invalid or stale, so
2031  *   ND6_EXCLUSIVE lock needs to be acquired
2032  * 2) destination lle is provided (with ND6_EXCLUSIVE lock),
2033  *   in that case packets are queued in &chain.
2034  *
2035  */
2036 static int
2037 nd6_output_lle(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
2038     struct sockaddr_in6 *dst)
2039 {
2040 	struct llentry *lle = NULL, *lle_tmp;
2041 
2042 	KASSERT(m != NULL, ("NULL mbuf, nothing to send"));
2043 	/* discard the packet if IPv6 operation is disabled on the interface */
2044 	if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) {
2045 		m_freem(m);
2046 		return (ENETDOWN); /* better error? */
2047 	}
2048 
2049 	if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
2050 		goto sendpkt;
2051 
2052 	if (nd6_need_cache(ifp) == 0)
2053 		goto sendpkt;
2054 
2055 	/*
2056 	 * Address resolution or Neighbor Unreachability Detection
2057 	 * for the next hop.
2058 	 * At this point, the destination of the packet must be a unicast
2059 	 * or an anycast address(i.e. not a multicast).
2060 	 */
2061 	if (lle == NULL) {
2062 		IF_AFDATA_RLOCK(ifp);
2063 		lle = nd6_lookup(&dst->sin6_addr, ND6_EXCLUSIVE, ifp);
2064 		IF_AFDATA_RUNLOCK(ifp);
2065 		if ((lle == NULL) && nd6_is_addr_neighbor(dst, ifp))  {
2066 			/*
2067 			 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
2068 			 * the condition below is not very efficient.  But we believe
2069 			 * it is tolerable, because this should be a rare case.
2070 			 */
2071 			lle = nd6_alloc(&dst->sin6_addr, 0, ifp);
2072 			if (lle == NULL) {
2073 				char ip6buf[INET6_ADDRSTRLEN];
2074 				log(LOG_DEBUG,
2075 				    "nd6_output: can't allocate llinfo for %s "
2076 				    "(ln=%p)\n",
2077 				    ip6_sprintf(ip6buf, &dst->sin6_addr), lle);
2078 				m_freem(m);
2079 				return (ENOBUFS);
2080 			}
2081 			lle->ln_state = ND6_LLINFO_NOSTATE;
2082 
2083 			IF_AFDATA_WLOCK(ifp);
2084 			LLE_WLOCK(lle);
2085 			/* Prefer any existing entry over newly-created one */
2086 			lle_tmp = nd6_lookup(&dst->sin6_addr, ND6_EXCLUSIVE, ifp);
2087 			if (lle_tmp == NULL)
2088 				lltable_link_entry(LLTABLE6(ifp), lle);
2089 			IF_AFDATA_WUNLOCK(ifp);
2090 			if (lle_tmp != NULL) {
2091 				lltable_free_entry(LLTABLE6(ifp), lle);
2092 				lle = lle_tmp;
2093 				lle_tmp = NULL;
2094 			}
2095 		}
2096 	}
2097 	if (lle == NULL) {
2098 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0 &&
2099 		    !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) {
2100 			m_freem(m);
2101 			return (ENOBUFS);
2102 		}
2103 		goto sendpkt;	/* send anyway */
2104 	}
2105 
2106 	LLE_WLOCK_ASSERT(lle);
2107 
2108 	/* We don't have to do link-layer address resolution on a p2p link. */
2109 	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
2110 	    lle->ln_state < ND6_LLINFO_REACHABLE) {
2111 		lle->ln_state = ND6_LLINFO_STALE;
2112 		nd6_llinfo_settimer_locked(lle, (long)V_nd6_gctimer * hz);
2113 	}
2114 
2115 	/*
2116 	 * The first time we send a packet to a neighbor whose entry is
2117 	 * STALE, we have to change the state to DELAY and a sets a timer to
2118 	 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
2119 	 * neighbor unreachability detection on expiration.
2120 	 * (RFC 2461 7.3.3)
2121 	 */
2122 	if (lle->ln_state == ND6_LLINFO_STALE) {
2123 		lle->la_asked = 0;
2124 		lle->ln_state = ND6_LLINFO_DELAY;
2125 		nd6_llinfo_settimer_locked(lle, (long)V_nd6_delay * hz);
2126 	}
2127 
2128 	/*
2129 	 * If the neighbor cache entry has a state other than INCOMPLETE
2130 	 * (i.e. its link-layer address is already resolved), just
2131 	 * send the packet.
2132 	 */
2133 	if (lle->ln_state > ND6_LLINFO_INCOMPLETE)
2134 		goto sendpkt;
2135 
2136 	/*
2137 	 * There is a neighbor cache entry, but no ethernet address
2138 	 * response yet.  Append this latest packet to the end of the
2139 	 * packet queue in the mbuf, unless the number of the packet
2140 	 * does not exceed nd6_maxqueuelen.  When it exceeds nd6_maxqueuelen,
2141 	 * the oldest packet in the queue will be removed.
2142 	 */
2143 	if (lle->ln_state == ND6_LLINFO_NOSTATE)
2144 		lle->ln_state = ND6_LLINFO_INCOMPLETE;
2145 
2146 	if (lle->la_hold != NULL) {
2147 		struct mbuf *m_hold;
2148 		int i;
2149 
2150 		i = 0;
2151 		for (m_hold = lle->la_hold; m_hold; m_hold = m_hold->m_nextpkt){
2152 			i++;
2153 			if (m_hold->m_nextpkt == NULL) {
2154 				m_hold->m_nextpkt = m;
2155 				break;
2156 			}
2157 		}
2158 		while (i >= V_nd6_maxqueuelen) {
2159 			m_hold = lle->la_hold;
2160 			lle->la_hold = lle->la_hold->m_nextpkt;
2161 			m_freem(m_hold);
2162 			i--;
2163 		}
2164 	} else {
2165 		lle->la_hold = m;
2166 	}
2167 
2168 	/*
2169 	 * If there has been no NS for the neighbor after entering the
2170 	 * INCOMPLETE state, send the first solicitation.
2171 	 */
2172 	if (!ND6_LLINFO_PERMANENT(lle) && lle->la_asked == 0) {
2173 		lle->la_asked++;
2174 
2175 		nd6_llinfo_settimer_locked(lle,
2176 		    (long)ND_IFINFO(ifp)->retrans * hz / 1000);
2177 		LLE_WUNLOCK(lle);
2178 		nd6_ns_output(ifp, NULL, &dst->sin6_addr, lle, NULL);
2179 	} else {
2180 		/* We did the lookup so we need to do the unlock here. */
2181 		LLE_WUNLOCK(lle);
2182 	}
2183 
2184 	return (0);
2185 
2186   sendpkt:
2187 	if (lle != NULL)
2188 		LLE_WUNLOCK(lle);
2189 
2190 	return (nd6_output_ifp(ifp, origifp, m, dst));
2191 }
2192 
2193 
2194 int
2195 nd6_flush_holdchain(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *chain,
2196     struct sockaddr_in6 *dst)
2197 {
2198 	struct mbuf *m, *m_head;
2199 	struct ifnet *outifp;
2200 	int error = 0;
2201 
2202 	m_head = chain;
2203 	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2204 		outifp = origifp;
2205 	else
2206 		outifp = ifp;
2207 
2208 	while (m_head) {
2209 		m = m_head;
2210 		m_head = m_head->m_nextpkt;
2211 		error = nd6_output_ifp(ifp, origifp, m, dst);
2212 	}
2213 
2214 	/*
2215 	 * XXX
2216 	 * note that intermediate errors are blindly ignored - but this is
2217 	 * the same convention as used with nd6_output when called by
2218 	 * nd6_cache_lladdr
2219 	 */
2220 	return (error);
2221 }
2222 
2223 
2224 int
2225 nd6_need_cache(struct ifnet *ifp)
2226 {
2227 	/*
2228 	 * XXX: we currently do not make neighbor cache on any interface
2229 	 * other than ARCnet, Ethernet, FDDI and GIF.
2230 	 *
2231 	 * RFC2893 says:
2232 	 * - unidirectional tunnels needs no ND
2233 	 */
2234 	switch (ifp->if_type) {
2235 	case IFT_ARCNET:
2236 	case IFT_ETHER:
2237 	case IFT_FDDI:
2238 	case IFT_IEEE1394:
2239 	case IFT_L2VLAN:
2240 	case IFT_IEEE80211:
2241 	case IFT_INFINIBAND:
2242 	case IFT_BRIDGE:
2243 	case IFT_PROPVIRTUAL:
2244 		return (1);
2245 	default:
2246 		return (0);
2247 	}
2248 }
2249 
2250 /*
2251  * Add pernament ND6 link-layer record for given
2252  * interface address.
2253  *
2254  * Very similar to IPv4 arp_ifinit(), but:
2255  * 1) IPv6 DAD is performed in different place
2256  * 2) It is called by IPv6 protocol stack in contrast to
2257  * arp_ifinit() which is typically called in SIOCSIFADDR
2258  * driver ioctl handler.
2259  *
2260  */
2261 int
2262 nd6_add_ifa_lle(struct in6_ifaddr *ia)
2263 {
2264 	struct ifnet *ifp;
2265 	struct llentry *ln, *ln_tmp;
2266 	struct sockaddr *dst;
2267 
2268 	ifp = ia->ia_ifa.ifa_ifp;
2269 	if (nd6_need_cache(ifp) == 0)
2270 		return (0);
2271 
2272 	ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
2273 	dst = (struct sockaddr *)&ia->ia_addr;
2274 	ln = lltable_alloc_entry(LLTABLE6(ifp), LLE_IFADDR, dst);
2275 	if (ln == NULL)
2276 		return (ENOBUFS);
2277 
2278 	IF_AFDATA_WLOCK(ifp);
2279 	LLE_WLOCK(ln);
2280 	/* Unlink any entry if exists */
2281 	ln_tmp = lla_lookup(LLTABLE6(ifp), LLE_EXCLUSIVE, dst);
2282 	if (ln_tmp != NULL)
2283 		lltable_unlink_entry(LLTABLE6(ifp), ln_tmp);
2284 	lltable_link_entry(LLTABLE6(ifp), ln);
2285 	IF_AFDATA_WUNLOCK(ifp);
2286 
2287 	if (ln_tmp != NULL)
2288 		EVENTHANDLER_INVOKE(lle_event, ln_tmp, LLENTRY_EXPIRED);
2289 	EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED);
2290 
2291 	LLE_WUNLOCK(ln);
2292 	if (ln_tmp != NULL)
2293 		llentry_free(ln_tmp);
2294 
2295 	return (0);
2296 }
2297 
2298 /*
2299  * Removes ALL lle records for interface address prefix.
2300  * XXXME: That's probably not we really want to do, we need
2301  * to remove address record only and keep other records
2302  * until we determine if given prefix is really going
2303  * to be removed.
2304  */
2305 void
2306 nd6_rem_ifa_lle(struct in6_ifaddr *ia)
2307 {
2308 	struct sockaddr_in6 mask, addr;
2309 	struct ifnet *ifp;
2310 
2311 	ifp = ia->ia_ifa.ifa_ifp;
2312 	memcpy(&addr, &ia->ia_addr, sizeof(ia->ia_addr));
2313 	memcpy(&mask, &ia->ia_prefixmask, sizeof(ia->ia_prefixmask));
2314 	lltable_prefix_free(AF_INET6, (struct sockaddr *)&addr,
2315 	            (struct sockaddr *)&mask, LLE_STATIC);
2316 }
2317 
2318 /*
2319  * the callers of this function need to be re-worked to drop
2320  * the lle lock, drop here for now
2321  */
2322 int
2323 nd6_storelladdr(struct ifnet *ifp, struct mbuf *m,
2324     const struct sockaddr *dst, u_char *desten, uint32_t *pflags)
2325 {
2326 	struct llentry *ln;
2327 
2328 	if (pflags != NULL)
2329 		*pflags = 0;
2330 	IF_AFDATA_UNLOCK_ASSERT(ifp);
2331 	if (m != NULL && m->m_flags & M_MCAST) {
2332 		switch (ifp->if_type) {
2333 		case IFT_ETHER:
2334 		case IFT_FDDI:
2335 		case IFT_L2VLAN:
2336 		case IFT_IEEE80211:
2337 		case IFT_BRIDGE:
2338 		case IFT_ISO88025:
2339 			ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr,
2340 						 desten);
2341 			return (0);
2342 		default:
2343 			m_freem(m);
2344 			return (EAFNOSUPPORT);
2345 		}
2346 	}
2347 
2348 
2349 	/*
2350 	 * the entry should have been created in nd6_store_lladdr
2351 	 */
2352 	IF_AFDATA_RLOCK(ifp);
2353 	ln = lla_lookup(LLTABLE6(ifp), 0, dst);
2354 	IF_AFDATA_RUNLOCK(ifp);
2355 	if ((ln == NULL) || !(ln->la_flags & LLE_VALID)) {
2356 		if (ln != NULL)
2357 			LLE_RUNLOCK(ln);
2358 		/* this could happen, if we could not allocate memory */
2359 		m_freem(m);
2360 		return (1);
2361 	}
2362 
2363 	bcopy(&ln->ll_addr, desten, ifp->if_addrlen);
2364 	if (pflags != NULL)
2365 		*pflags = ln->la_flags;
2366 	LLE_RUNLOCK(ln);
2367 	/*
2368 	 * A *small* use after free race exists here
2369 	 */
2370 	return (0);
2371 }
2372 
2373 static void
2374 clear_llinfo_pqueue(struct llentry *ln)
2375 {
2376 	struct mbuf *m_hold, *m_hold_next;
2377 
2378 	for (m_hold = ln->la_hold; m_hold; m_hold = m_hold_next) {
2379 		m_hold_next = m_hold->m_nextpkt;
2380 		m_freem(m_hold);
2381 	}
2382 
2383 	ln->la_hold = NULL;
2384 	return;
2385 }
2386 
2387 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
2388 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
2389 #ifdef SYSCTL_DECL
2390 SYSCTL_DECL(_net_inet6_icmp6);
2391 #endif
2392 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2393 	CTLFLAG_RD, nd6_sysctl_drlist, "");
2394 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
2395 	CTLFLAG_RD, nd6_sysctl_prlist, "");
2396 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen,
2397 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, "");
2398 SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, nd6_gctimer,
2399 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_gctimer), (60 * 60 * 24), "");
2400 
2401 static int
2402 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2403 {
2404 	struct in6_defrouter d;
2405 	struct nd_defrouter *dr;
2406 	int error;
2407 
2408 	if (req->newptr)
2409 		return (EPERM);
2410 
2411 	bzero(&d, sizeof(d));
2412 	d.rtaddr.sin6_family = AF_INET6;
2413 	d.rtaddr.sin6_len = sizeof(d.rtaddr);
2414 
2415 	/*
2416 	 * XXX locking
2417 	 */
2418 	TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
2419 		d.rtaddr.sin6_addr = dr->rtaddr;
2420 		error = sa6_recoverscope(&d.rtaddr);
2421 		if (error != 0)
2422 			return (error);
2423 		d.flags = dr->flags;
2424 		d.rtlifetime = dr->rtlifetime;
2425 		d.expire = dr->expire + (time_second - time_uptime);
2426 		d.if_index = dr->ifp->if_index;
2427 		error = SYSCTL_OUT(req, &d, sizeof(d));
2428 		if (error != 0)
2429 			return (error);
2430 	}
2431 	return (0);
2432 }
2433 
2434 static int
2435 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
2436 {
2437 	struct in6_prefix p;
2438 	struct sockaddr_in6 s6;
2439 	struct nd_prefix *pr;
2440 	struct nd_pfxrouter *pfr;
2441 	time_t maxexpire;
2442 	int error;
2443 	char ip6buf[INET6_ADDRSTRLEN];
2444 
2445 	if (req->newptr)
2446 		return (EPERM);
2447 
2448 	bzero(&p, sizeof(p));
2449 	p.origin = PR_ORIG_RA;
2450 	bzero(&s6, sizeof(s6));
2451 	s6.sin6_family = AF_INET6;
2452 	s6.sin6_len = sizeof(s6);
2453 
2454 	/*
2455 	 * XXX locking
2456 	 */
2457 	LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
2458 		p.prefix = pr->ndpr_prefix;
2459 		if (sa6_recoverscope(&p.prefix)) {
2460 			log(LOG_ERR, "scope error in prefix list (%s)\n",
2461 			    ip6_sprintf(ip6buf, &p.prefix.sin6_addr));
2462 			/* XXX: press on... */
2463 		}
2464 		p.raflags = pr->ndpr_raf;
2465 		p.prefixlen = pr->ndpr_plen;
2466 		p.vltime = pr->ndpr_vltime;
2467 		p.pltime = pr->ndpr_pltime;
2468 		p.if_index = pr->ndpr_ifp->if_index;
2469 		if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME)
2470 			p.expire = 0;
2471 		else {
2472 			/* XXX: we assume time_t is signed. */
2473 			maxexpire = (-1) &
2474 			    ~((time_t)1 << ((sizeof(maxexpire) * 8) - 1));
2475 			if (pr->ndpr_vltime < maxexpire - pr->ndpr_lastupdate)
2476 				p.expire = pr->ndpr_lastupdate +
2477 				    pr->ndpr_vltime +
2478 				    (time_second - time_uptime);
2479 			else
2480 				p.expire = maxexpire;
2481 		}
2482 		p.refcnt = pr->ndpr_refcnt;
2483 		p.flags = pr->ndpr_stateflags;
2484 		p.advrtrs = 0;
2485 		LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry)
2486 			p.advrtrs++;
2487 		error = SYSCTL_OUT(req, &p, sizeof(p));
2488 		if (error != 0)
2489 			return (error);
2490 		LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) {
2491 			s6.sin6_addr = pfr->router->rtaddr;
2492 			if (sa6_recoverscope(&s6))
2493 				log(LOG_ERR,
2494 				    "scope error in prefix list (%s)\n",
2495 				    ip6_sprintf(ip6buf, &pfr->router->rtaddr));
2496 			error = SYSCTL_OUT(req, &s6, sizeof(s6));
2497 			if (error != 0)
2498 				return (error);
2499 		}
2500 	}
2501 	return (0);
2502 }
2503