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: releng/10.3/sys/netinet6/nd6.c 292566 2015-12-21 20:29:55Z kp $");
34
35#include "opt_inet.h"
36#include "opt_inet6.h"
37#include "opt_kdtrace.h"
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/callout.h>
42#include <sys/malloc.h>
43#include <sys/mbuf.h>
44#include <sys/socket.h>
45#include <sys/sockio.h>
46#include <sys/time.h>
47#include <sys/kernel.h>
48#include <sys/protosw.h>
49#include <sys/errno.h>
50#include <sys/syslog.h>
51#include <sys/lock.h>
52#include <sys/rwlock.h>
53#include <sys/queue.h>
54#include <sys/sdt.h>
55#include <sys/sysctl.h>
56
57#include <net/if.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#define	L3_ADDR_SIN6(le)	((struct sockaddr_in6 *) L3_ADDR(le))
70#include <netinet/if_ether.h>
71#include <netinet6/in6_var.h>
72#include <netinet/ip6.h>
73#include <netinet6/ip6_var.h>
74#include <netinet6/scope6_var.h>
75#include <netinet6/nd6.h>
76#include <netinet6/in6_ifattach.h>
77#include <netinet/icmp6.h>
78#include <netinet6/send.h>
79
80#include <sys/limits.h>
81
82#include <security/mac/mac_framework.h>
83
84#define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
85#define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
86
87#define SIN6(s) ((const struct sockaddr_in6 *)(s))
88
89/* timer values */
90VNET_DEFINE(int, nd6_prune)	= 1;	/* walk list every 1 seconds */
91VNET_DEFINE(int, nd6_delay)	= 5;	/* delay first probe time 5 second */
92VNET_DEFINE(int, nd6_umaxtries)	= 3;	/* maximum unicast query */
93VNET_DEFINE(int, nd6_mmaxtries)	= 3;	/* maximum multicast query */
94VNET_DEFINE(int, nd6_useloopback) = 1;	/* use loopback interface for
95					 * local traffic */
96VNET_DEFINE(int, nd6_gctimer)	= (60 * 60 * 24); /* 1 day: garbage
97					 * collection timer */
98
99/* preventing too many loops in ND option parsing */
100static VNET_DEFINE(int, nd6_maxndopt) = 10; /* max # of ND options allowed */
101
102VNET_DEFINE(int, nd6_maxnudhint) = 0;	/* max # of subsequent upper
103					 * layer hints */
104static VNET_DEFINE(int, nd6_maxqueuelen) = 1; /* max pkts cached in unresolved
105					 * ND entries */
106#define	V_nd6_maxndopt			VNET(nd6_maxndopt)
107#define	V_nd6_maxqueuelen		VNET(nd6_maxqueuelen)
108
109#ifdef ND6_DEBUG
110VNET_DEFINE(int, nd6_debug) = 1;
111#else
112VNET_DEFINE(int, nd6_debug) = 0;
113#endif
114
115/* for debugging? */
116#if 0
117static int nd6_inuse, nd6_allocated;
118#endif
119
120VNET_DEFINE(struct nd_drhead, nd_defrouter);
121VNET_DEFINE(struct nd_prhead, nd_prefix);
122
123VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL;
124#define	V_nd6_recalc_reachtm_interval	VNET(nd6_recalc_reachtm_interval)
125
126int	(*send_sendso_input_hook)(struct mbuf *, struct ifnet *, int, int);
127
128static int nd6_is_new_addr_neighbor(struct sockaddr_in6 *,
129	struct ifnet *);
130static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *);
131static void nd6_slowtimo(void *);
132static int regen_tmpaddr(struct in6_ifaddr *);
133static struct llentry *nd6_free(struct llentry *, int);
134static void nd6_llinfo_timer(void *);
135static void clear_llinfo_pqueue(struct llentry *);
136static int nd6_output_lle(struct ifnet *, struct ifnet *, struct mbuf *,
137	struct sockaddr_in6 *);
138static int nd6_output_ifp(struct ifnet *, struct ifnet *, struct mbuf *,
139    struct sockaddr_in6 *);
140
141static VNET_DEFINE(struct callout, nd6_slowtimo_ch);
142#define	V_nd6_slowtimo_ch		VNET(nd6_slowtimo_ch)
143
144VNET_DEFINE(struct callout, nd6_timer_ch);
145
146void
147nd6_init(void)
148{
149
150	LIST_INIT(&V_nd_prefix);
151
152	/* initialization of the default router list */
153	TAILQ_INIT(&V_nd_defrouter);
154
155	/* start timer */
156	callout_init(&V_nd6_slowtimo_ch, 0);
157	callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
158	    nd6_slowtimo, curvnet);
159
160	nd6_dad_init();
161}
162
163#ifdef VIMAGE
164void
165nd6_destroy()
166{
167
168	callout_drain(&V_nd6_slowtimo_ch);
169	callout_drain(&V_nd6_timer_ch);
170}
171#endif
172
173struct nd_ifinfo *
174nd6_ifattach(struct ifnet *ifp)
175{
176	struct nd_ifinfo *nd;
177
178	nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK|M_ZERO);
179	nd->initialized = 1;
180
181	nd->chlim = IPV6_DEFHLIM;
182	nd->basereachable = REACHABLE_TIME;
183	nd->reachable = ND_COMPUTE_RTIME(nd->basereachable);
184	nd->retrans = RETRANS_TIMER;
185
186	nd->flags = ND6_IFF_PERFORMNUD;
187
188	/* A loopback interface always has ND6_IFF_AUTO_LINKLOCAL.
189	 * XXXHRS: Clear ND6_IFF_AUTO_LINKLOCAL on an IFT_BRIDGE interface by
190	 * default regardless of the V_ip6_auto_linklocal configuration to
191	 * give a reasonable default behavior.
192	 */
193	if ((V_ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) ||
194	    (ifp->if_flags & IFF_LOOPBACK))
195		nd->flags |= ND6_IFF_AUTO_LINKLOCAL;
196	/*
197	 * A loopback interface does not need to accept RTADV.
198	 * XXXHRS: Clear ND6_IFF_ACCEPT_RTADV on an IFT_BRIDGE interface by
199	 * default regardless of the V_ip6_accept_rtadv configuration to
200	 * prevent the interface from accepting RA messages arrived
201	 * on one of the member interfaces with ND6_IFF_ACCEPT_RTADV.
202	 */
203	if (V_ip6_accept_rtadv &&
204	    !(ifp->if_flags & IFF_LOOPBACK) &&
205	    (ifp->if_type != IFT_BRIDGE))
206			nd->flags |= ND6_IFF_ACCEPT_RTADV;
207	if (V_ip6_no_radr && !(ifp->if_flags & IFF_LOOPBACK))
208		nd->flags |= ND6_IFF_NO_RADR;
209
210	/* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
211	nd6_setmtu0(ifp, nd);
212
213	return nd;
214}
215
216void
217nd6_ifdetach(struct nd_ifinfo *nd)
218{
219
220	free(nd, M_IP6NDP);
221}
222
223/*
224 * Reset ND level link MTU. This function is called when the physical MTU
225 * changes, which means we might have to adjust the ND level MTU.
226 */
227void
228nd6_setmtu(struct ifnet *ifp)
229{
230	if (ifp->if_afdata[AF_INET6] == NULL)
231		return;
232
233	nd6_setmtu0(ifp, ND_IFINFO(ifp));
234}
235
236/* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
237void
238nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi)
239{
240	u_int32_t omaxmtu;
241
242	omaxmtu = ndi->maxmtu;
243
244	switch (ifp->if_type) {
245	case IFT_ARCNET:
246		ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */
247		break;
248	case IFT_FDDI:
249		ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); /* RFC2467 */
250		break;
251	case IFT_ISO88025:
252		 ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu);
253		 break;
254	default:
255		ndi->maxmtu = ifp->if_mtu;
256		break;
257	}
258
259	/*
260	 * Decreasing the interface MTU under IPV6 minimum MTU may cause
261	 * undesirable situation.  We thus notify the operator of the change
262	 * explicitly.  The check for omaxmtu is necessary to restrict the
263	 * log to the case of changing the MTU, not initializing it.
264	 */
265	if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) {
266		log(LOG_NOTICE, "nd6_setmtu0: "
267		    "new link MTU on %s (%lu) is too small for IPv6\n",
268		    if_name(ifp), (unsigned long)ndi->maxmtu);
269	}
270
271	if (ndi->maxmtu > V_in6_maxmtu)
272		in6_setmaxmtu(); /* check all interfaces just in case */
273
274}
275
276void
277nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
278{
279
280	bzero(ndopts, sizeof(*ndopts));
281	ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
282	ndopts->nd_opts_last
283		= (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
284
285	if (icmp6len == 0) {
286		ndopts->nd_opts_done = 1;
287		ndopts->nd_opts_search = NULL;
288	}
289}
290
291/*
292 * Take one ND option.
293 */
294struct nd_opt_hdr *
295nd6_option(union nd_opts *ndopts)
296{
297	struct nd_opt_hdr *nd_opt;
298	int olen;
299
300	KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__));
301	KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts",
302	    __func__));
303	if (ndopts->nd_opts_search == NULL)
304		return NULL;
305	if (ndopts->nd_opts_done)
306		return NULL;
307
308	nd_opt = ndopts->nd_opts_search;
309
310	/* make sure nd_opt_len is inside the buffer */
311	if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) {
312		bzero(ndopts, sizeof(*ndopts));
313		return NULL;
314	}
315
316	olen = nd_opt->nd_opt_len << 3;
317	if (olen == 0) {
318		/*
319		 * Message validation requires that all included
320		 * options have a length that is greater than zero.
321		 */
322		bzero(ndopts, sizeof(*ndopts));
323		return NULL;
324	}
325
326	ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen);
327	if (ndopts->nd_opts_search > ndopts->nd_opts_last) {
328		/* option overruns the end of buffer, invalid */
329		bzero(ndopts, sizeof(*ndopts));
330		return NULL;
331	} else if (ndopts->nd_opts_search == ndopts->nd_opts_last) {
332		/* reached the end of options chain */
333		ndopts->nd_opts_done = 1;
334		ndopts->nd_opts_search = NULL;
335	}
336	return nd_opt;
337}
338
339/*
340 * Parse multiple ND options.
341 * This function is much easier to use, for ND routines that do not need
342 * multiple options of the same type.
343 */
344int
345nd6_options(union nd_opts *ndopts)
346{
347	struct nd_opt_hdr *nd_opt;
348	int i = 0;
349
350	KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__));
351	KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts",
352	    __func__));
353	if (ndopts->nd_opts_search == NULL)
354		return 0;
355
356	while (1) {
357		nd_opt = nd6_option(ndopts);
358		if (nd_opt == NULL && ndopts->nd_opts_last == NULL) {
359			/*
360			 * Message validation requires that all included
361			 * options have a length that is greater than zero.
362			 */
363			ICMP6STAT_INC(icp6s_nd_badopt);
364			bzero(ndopts, sizeof(*ndopts));
365			return -1;
366		}
367
368		if (nd_opt == NULL)
369			goto skip1;
370
371		switch (nd_opt->nd_opt_type) {
372		case ND_OPT_SOURCE_LINKADDR:
373		case ND_OPT_TARGET_LINKADDR:
374		case ND_OPT_MTU:
375		case ND_OPT_REDIRECTED_HEADER:
376		case ND_OPT_NONCE:
377			if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
378				nd6log((LOG_INFO,
379				    "duplicated ND6 option found (type=%d)\n",
380				    nd_opt->nd_opt_type));
381				/* XXX bark? */
382			} else {
383				ndopts->nd_opt_array[nd_opt->nd_opt_type]
384					= nd_opt;
385			}
386			break;
387		case ND_OPT_PREFIX_INFORMATION:
388			if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) {
389				ndopts->nd_opt_array[nd_opt->nd_opt_type]
390					= nd_opt;
391			}
392			ndopts->nd_opts_pi_end =
393				(struct nd_opt_prefix_info *)nd_opt;
394			break;
395		/* What about ND_OPT_ROUTE_INFO? RFC 4191 */
396		case ND_OPT_RDNSS:	/* RFC 6106 */
397		case ND_OPT_DNSSL:	/* RFC 6106 */
398			/*
399			 * Silently ignore options we know and do not care about
400			 * in the kernel.
401			 */
402			break;
403		default:
404			/*
405			 * Unknown options must be silently ignored,
406			 * to accomodate future extension to the protocol.
407			 */
408			nd6log((LOG_DEBUG,
409			    "nd6_options: unsupported option %d - "
410			    "option ignored\n", nd_opt->nd_opt_type));
411		}
412
413skip1:
414		i++;
415		if (i > V_nd6_maxndopt) {
416			ICMP6STAT_INC(icp6s_nd_toomanyopt);
417			nd6log((LOG_INFO, "too many loop in nd opt\n"));
418			break;
419		}
420
421		if (ndopts->nd_opts_done)
422			break;
423	}
424
425	return 0;
426}
427
428/*
429 * ND6 timer routine to handle ND6 entries
430 */
431void
432nd6_llinfo_settimer_locked(struct llentry *ln, long tick)
433{
434	int canceled;
435
436	LLE_WLOCK_ASSERT(ln);
437
438	if (tick < 0) {
439		ln->la_expire = 0;
440		ln->ln_ntick = 0;
441		canceled = callout_stop(&ln->ln_timer_ch);
442	} else {
443		ln->la_expire = time_uptime + tick / hz;
444		LLE_ADDREF(ln);
445		if (tick > INT_MAX) {
446			ln->ln_ntick = tick - INT_MAX;
447			canceled = callout_reset(&ln->ln_timer_ch, INT_MAX,
448			    nd6_llinfo_timer, ln);
449		} else {
450			ln->ln_ntick = 0;
451			canceled = callout_reset(&ln->ln_timer_ch, tick,
452			    nd6_llinfo_timer, ln);
453		}
454	}
455	if (canceled)
456		LLE_REMREF(ln);
457}
458
459void
460nd6_llinfo_settimer(struct llentry *ln, long tick)
461{
462
463	LLE_WLOCK(ln);
464	nd6_llinfo_settimer_locked(ln, tick);
465	LLE_WUNLOCK(ln);
466}
467
468static void
469nd6_llinfo_timer(void *arg)
470{
471	struct llentry *ln;
472	struct in6_addr *dst;
473	struct ifnet *ifp;
474	struct nd_ifinfo *ndi = NULL;
475
476	KASSERT(arg != NULL, ("%s: arg NULL", __func__));
477	ln = (struct llentry *)arg;
478	LLE_WLOCK(ln);
479	if (callout_pending(&ln->la_timer)) {
480		/*
481		 * Here we are a bit odd here in the treatment of
482		 * active/pending. If the pending bit is set, it got
483		 * rescheduled before I ran. The active
484		 * bit we ignore, since if it was stopped
485		 * in ll_tablefree() and was currently running
486		 * it would have return 0 so the code would
487		 * not have deleted it since the callout could
488		 * not be stopped so we want to go through
489		 * with the delete here now. If the callout
490		 * was restarted, the pending bit will be back on and
491		 * we just want to bail since the callout_reset would
492		 * return 1 and our reference would have been removed
493		 * by nd6_llinfo_settimer_locked above since canceled
494		 * would have been 1.
495		 */
496		LLE_WUNLOCK(ln);
497		return;
498	}
499	ifp = ln->lle_tbl->llt_ifp;
500	CURVNET_SET(ifp->if_vnet);
501
502	if (ln->ln_ntick > 0) {
503		if (ln->ln_ntick > INT_MAX) {
504			ln->ln_ntick -= INT_MAX;
505			nd6_llinfo_settimer_locked(ln, INT_MAX);
506		} else {
507			ln->ln_ntick = 0;
508			nd6_llinfo_settimer_locked(ln, ln->ln_ntick);
509		}
510		goto done;
511	}
512
513	ndi = ND_IFINFO(ifp);
514	dst = &L3_ADDR_SIN6(ln)->sin6_addr;
515	if (ln->la_flags & LLE_STATIC) {
516		goto done;
517	}
518
519	if (ln->la_flags & LLE_DELETED) {
520		(void)nd6_free(ln, 0);
521		ln = NULL;
522		goto done;
523	}
524
525	switch (ln->ln_state) {
526	case ND6_LLINFO_INCOMPLETE:
527		if (ln->la_asked < V_nd6_mmaxtries) {
528			ln->la_asked++;
529			nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
530			LLE_WUNLOCK(ln);
531			nd6_ns_output(ifp, NULL, dst, ln, NULL);
532			LLE_WLOCK(ln);
533		} else {
534			struct mbuf *m = ln->la_hold;
535			if (m) {
536				struct mbuf *m0;
537
538				/*
539				 * assuming every packet in la_hold has the
540				 * same IP header.  Send error after unlock.
541				 */
542				m0 = m->m_nextpkt;
543				m->m_nextpkt = NULL;
544				ln->la_hold = m0;
545				clear_llinfo_pqueue(ln);
546			}
547			EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_TIMEDOUT);
548			(void)nd6_free(ln, 0);
549			ln = NULL;
550			if (m != NULL)
551				icmp6_error2(m, ICMP6_DST_UNREACH,
552				    ICMP6_DST_UNREACH_ADDR, 0, ifp);
553		}
554		break;
555	case ND6_LLINFO_REACHABLE:
556		if (!ND6_LLINFO_PERMANENT(ln)) {
557			ln->ln_state = ND6_LLINFO_STALE;
558			nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
559		}
560		break;
561
562	case ND6_LLINFO_STALE:
563		/* Garbage Collection(RFC 2461 5.3) */
564		if (!ND6_LLINFO_PERMANENT(ln)) {
565			EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED);
566			(void)nd6_free(ln, 1);
567			ln = NULL;
568		}
569		break;
570
571	case ND6_LLINFO_DELAY:
572		if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) {
573			/* We need NUD */
574			ln->la_asked = 1;
575			ln->ln_state = ND6_LLINFO_PROBE;
576			nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
577			LLE_WUNLOCK(ln);
578			nd6_ns_output(ifp, dst, dst, ln, NULL);
579			LLE_WLOCK(ln);
580		} else {
581			ln->ln_state = ND6_LLINFO_STALE; /* XXX */
582			nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
583		}
584		break;
585	case ND6_LLINFO_PROBE:
586		if (ln->la_asked < V_nd6_umaxtries) {
587			ln->la_asked++;
588			nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
589			LLE_WUNLOCK(ln);
590			nd6_ns_output(ifp, dst, dst, ln, NULL);
591			LLE_WLOCK(ln);
592		} else {
593			EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED);
594			(void)nd6_free(ln, 0);
595			ln = NULL;
596		}
597		break;
598	default:
599		panic("%s: paths in a dark night can be confusing: %d",
600		    __func__, ln->ln_state);
601	}
602done:
603	if (ln != NULL)
604		LLE_FREE_LOCKED(ln);
605	CURVNET_RESTORE();
606}
607
608
609/*
610 * ND6 timer routine to expire default route list and prefix list
611 */
612void
613nd6_timer(void *arg)
614{
615	CURVNET_SET((struct vnet *) arg);
616	struct nd_defrouter *dr, *ndr;
617	struct nd_prefix *pr, *npr;
618	struct in6_ifaddr *ia6, *nia6;
619
620	callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz,
621	    nd6_timer, curvnet);
622
623	/* expire default router list */
624	TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
625		if (dr->expire && dr->expire < time_uptime)
626			defrtrlist_del(dr);
627	}
628
629	/*
630	 * expire interface addresses.
631	 * in the past the loop was inside prefix expiry processing.
632	 * However, from a stricter speci-confrmance standpoint, we should
633	 * rather separate address lifetimes and prefix lifetimes.
634	 *
635	 * XXXRW: in6_ifaddrhead locking.
636	 */
637  addrloop:
638	TAILQ_FOREACH_SAFE(ia6, &V_in6_ifaddrhead, ia_link, nia6) {
639		/* check address lifetime */
640		if (IFA6_IS_INVALID(ia6)) {
641			int regen = 0;
642
643			/*
644			 * If the expiring address is temporary, try
645			 * regenerating a new one.  This would be useful when
646			 * we suspended a laptop PC, then turned it on after a
647			 * period that could invalidate all temporary
648			 * addresses.  Although we may have to restart the
649			 * loop (see below), it must be after purging the
650			 * address.  Otherwise, we'd see an infinite loop of
651			 * regeneration.
652			 */
653			if (V_ip6_use_tempaddr &&
654			    (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
655				if (regen_tmpaddr(ia6) == 0)
656					regen = 1;
657			}
658
659			in6_purgeaddr(&ia6->ia_ifa);
660
661			if (regen)
662				goto addrloop; /* XXX: see below */
663		} else if (IFA6_IS_DEPRECATED(ia6)) {
664			int oldflags = ia6->ia6_flags;
665
666			ia6->ia6_flags |= IN6_IFF_DEPRECATED;
667
668			/*
669			 * If a temporary address has just become deprecated,
670			 * regenerate a new one if possible.
671			 */
672			if (V_ip6_use_tempaddr &&
673			    (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
674			    (oldflags & IN6_IFF_DEPRECATED) == 0) {
675
676				if (regen_tmpaddr(ia6) == 0) {
677					/*
678					 * A new temporary address is
679					 * generated.
680					 * XXX: this means the address chain
681					 * has changed while we are still in
682					 * the loop.  Although the change
683					 * would not cause disaster (because
684					 * it's not a deletion, but an
685					 * addition,) we'd rather restart the
686					 * loop just for safety.  Or does this
687					 * significantly reduce performance??
688					 */
689					goto addrloop;
690				}
691			}
692		} else if ((ia6->ia6_flags & IN6_IFF_TENTATIVE) != 0) {
693			/*
694			 * Schedule DAD for a tentative address.  This happens
695			 * if the interface was down or not running
696			 * when the address was configured.
697			 */
698			int delay;
699
700			delay = arc4random() %
701			    (MAX_RTR_SOLICITATION_DELAY * hz);
702			nd6_dad_start((struct ifaddr *)ia6, delay);
703		} else {
704			/*
705			 * Check status of the interface.  If it is down,
706			 * mark the address as tentative for future DAD.
707			 */
708			if ((ia6->ia_ifp->if_flags & IFF_UP) == 0 ||
709			    (ia6->ia_ifp->if_drv_flags & IFF_DRV_RUNNING)
710				== 0 ||
711			    (ND_IFINFO(ia6->ia_ifp)->flags &
712				ND6_IFF_IFDISABLED) != 0) {
713				ia6->ia6_flags &= ~IN6_IFF_DUPLICATED;
714				ia6->ia6_flags |= IN6_IFF_TENTATIVE;
715			}
716			/*
717			 * A new RA might have made a deprecated address
718			 * preferred.
719			 */
720			ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
721		}
722	}
723
724	/* expire prefix list */
725	LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
726		/*
727		 * check prefix lifetime.
728		 * since pltime is just for autoconf, pltime processing for
729		 * prefix is not necessary.
730		 */
731		if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME &&
732		    time_uptime - pr->ndpr_lastupdate > pr->ndpr_vltime) {
733
734			/*
735			 * address expiration and prefix expiration are
736			 * separate.  NEVER perform in6_purgeaddr here.
737			 */
738			prelist_remove(pr);
739		}
740	}
741	CURVNET_RESTORE();
742}
743
744/*
745 * ia6 - deprecated/invalidated temporary address
746 */
747static int
748regen_tmpaddr(struct in6_ifaddr *ia6)
749{
750	struct ifaddr *ifa;
751	struct ifnet *ifp;
752	struct in6_ifaddr *public_ifa6 = NULL;
753
754	ifp = ia6->ia_ifa.ifa_ifp;
755	IF_ADDR_RLOCK(ifp);
756	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
757		struct in6_ifaddr *it6;
758
759		if (ifa->ifa_addr->sa_family != AF_INET6)
760			continue;
761
762		it6 = (struct in6_ifaddr *)ifa;
763
764		/* ignore no autoconf addresses. */
765		if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0)
766			continue;
767
768		/* ignore autoconf addresses with different prefixes. */
769		if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
770			continue;
771
772		/*
773		 * Now we are looking at an autoconf address with the same
774		 * prefix as ours.  If the address is temporary and is still
775		 * preferred, do not create another one.  It would be rare, but
776		 * could happen, for example, when we resume a laptop PC after
777		 * a long period.
778		 */
779		if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
780		    !IFA6_IS_DEPRECATED(it6)) {
781			public_ifa6 = NULL;
782			break;
783		}
784
785		/*
786		 * This is a public autoconf address that has the same prefix
787		 * as ours.  If it is preferred, keep it.  We can't break the
788		 * loop here, because there may be a still-preferred temporary
789		 * address with the prefix.
790		 */
791		if (!IFA6_IS_DEPRECATED(it6))
792			public_ifa6 = it6;
793	}
794	if (public_ifa6 != NULL)
795		ifa_ref(&public_ifa6->ia_ifa);
796	IF_ADDR_RUNLOCK(ifp);
797
798	if (public_ifa6 != NULL) {
799		int e;
800
801		if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) {
802			ifa_free(&public_ifa6->ia_ifa);
803			log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
804			    " tmp addr,errno=%d\n", e);
805			return (-1);
806		}
807		ifa_free(&public_ifa6->ia_ifa);
808		return (0);
809	}
810
811	return (-1);
812}
813
814/*
815 * Nuke neighbor cache/prefix/default router management table, right before
816 * ifp goes away.
817 */
818void
819nd6_purge(struct ifnet *ifp)
820{
821	struct nd_defrouter *dr, *ndr;
822	struct nd_prefix *pr, *npr;
823
824	/*
825	 * Nuke default router list entries toward ifp.
826	 * We defer removal of default router list entries that is installed
827	 * in the routing table, in order to keep additional side effects as
828	 * small as possible.
829	 */
830	TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
831		if (dr->installed)
832			continue;
833
834		if (dr->ifp == ifp)
835			defrtrlist_del(dr);
836	}
837
838	TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
839		if (!dr->installed)
840			continue;
841
842		if (dr->ifp == ifp)
843			defrtrlist_del(dr);
844	}
845
846	/* Nuke prefix list entries toward ifp */
847	LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
848		if (pr->ndpr_ifp == ifp) {
849			/*
850			 * Because if_detach() does *not* release prefixes
851			 * while purging addresses the reference count will
852			 * still be above zero. We therefore reset it to
853			 * make sure that the prefix really gets purged.
854			 */
855			pr->ndpr_refcnt = 0;
856
857			/*
858			 * Previously, pr->ndpr_addr is removed as well,
859			 * but I strongly believe we don't have to do it.
860			 * nd6_purge() is only called from in6_ifdetach(),
861			 * which removes all the associated interface addresses
862			 * by itself.
863			 * (jinmei@kame.net 20010129)
864			 */
865			prelist_remove(pr);
866		}
867	}
868
869	/* cancel default outgoing interface setting */
870	if (V_nd6_defifindex == ifp->if_index)
871		nd6_setdefaultiface(0);
872
873	if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
874		/* Refresh default router list. */
875		defrouter_select();
876	}
877
878	/* XXXXX
879	 * We do not nuke the neighbor cache entries here any more
880	 * because the neighbor cache is kept in if_afdata[AF_INET6].
881	 * nd6_purge() is invoked by in6_ifdetach() which is called
882	 * from if_detach() where everything gets purged. So let
883	 * in6_domifdetach() do the actual L2 table purging work.
884	 */
885}
886
887/*
888 * the caller acquires and releases the lock on the lltbls
889 * Returns the llentry locked
890 */
891struct llentry *
892nd6_lookup(struct in6_addr *addr6, int flags, struct ifnet *ifp)
893{
894	struct sockaddr_in6 sin6;
895	struct llentry *ln;
896	int llflags;
897
898	bzero(&sin6, sizeof(sin6));
899	sin6.sin6_len = sizeof(struct sockaddr_in6);
900	sin6.sin6_family = AF_INET6;
901	sin6.sin6_addr = *addr6;
902
903	IF_AFDATA_LOCK_ASSERT(ifp);
904
905	llflags = 0;
906	if (flags & ND6_CREATE)
907	    llflags |= LLE_CREATE;
908	if (flags & ND6_EXCLUSIVE)
909	    llflags |= LLE_EXCLUSIVE;
910
911	ln = lla_lookup(LLTABLE6(ifp), llflags, (struct sockaddr *)&sin6);
912	if ((ln != NULL) && (llflags & LLE_CREATE))
913		ln->ln_state = ND6_LLINFO_NOSTATE;
914
915	return (ln);
916}
917
918/*
919 * Test whether a given IPv6 address is a neighbor or not, ignoring
920 * the actual neighbor cache.  The neighbor cache is ignored in order
921 * to not reenter the routing code from within itself.
922 */
923static int
924nd6_is_new_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
925{
926	struct nd_prefix *pr;
927	struct ifaddr *dstaddr;
928
929	/*
930	 * A link-local address is always a neighbor.
931	 * XXX: a link does not necessarily specify a single interface.
932	 */
933	if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) {
934		struct sockaddr_in6 sin6_copy;
935		u_int32_t zone;
936
937		/*
938		 * We need sin6_copy since sa6_recoverscope() may modify the
939		 * content (XXX).
940		 */
941		sin6_copy = *addr;
942		if (sa6_recoverscope(&sin6_copy))
943			return (0); /* XXX: should be impossible */
944		if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone))
945			return (0);
946		if (sin6_copy.sin6_scope_id == zone)
947			return (1);
948		else
949			return (0);
950	}
951
952	/*
953	 * If the address matches one of our addresses,
954	 * it should be a neighbor.
955	 * If the address matches one of our on-link prefixes, it should be a
956	 * neighbor.
957	 */
958	LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
959		if (pr->ndpr_ifp != ifp)
960			continue;
961
962		if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) {
963			struct rtentry *rt;
964
965			/* Always use the default FIB here. */
966			rt = in6_rtalloc1((struct sockaddr *)&pr->ndpr_prefix,
967			    0, 0, RT_DEFAULT_FIB);
968			if (rt == NULL)
969				continue;
970			/*
971			 * This is the case where multiple interfaces
972			 * have the same prefix, but only one is installed
973			 * into the routing table and that prefix entry
974			 * is not the one being examined here. In the case
975			 * where RADIX_MPATH is enabled, multiple route
976			 * entries (of the same rt_key value) will be
977			 * installed because the interface addresses all
978			 * differ.
979			 */
980			if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
981			       &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr)) {
982				RTFREE_LOCKED(rt);
983				continue;
984			}
985			RTFREE_LOCKED(rt);
986		}
987
988		if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
989		    &addr->sin6_addr, &pr->ndpr_mask))
990			return (1);
991	}
992
993	/*
994	 * If the address is assigned on the node of the other side of
995	 * a p2p interface, the address should be a neighbor.
996	 */
997	dstaddr = ifa_ifwithdstaddr((struct sockaddr *)addr);
998	if (dstaddr != NULL) {
999		if (dstaddr->ifa_ifp == ifp) {
1000			ifa_free(dstaddr);
1001			return (1);
1002		}
1003		ifa_free(dstaddr);
1004	}
1005
1006	/*
1007	 * If the default router list is empty, all addresses are regarded
1008	 * as on-link, and thus, as a neighbor.
1009	 */
1010	if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV &&
1011	    TAILQ_EMPTY(&V_nd_defrouter) &&
1012	    V_nd6_defifindex == ifp->if_index) {
1013		return (1);
1014	}
1015
1016	return (0);
1017}
1018
1019
1020/*
1021 * Detect if a given IPv6 address identifies a neighbor on a given link.
1022 * XXX: should take care of the destination of a p2p link?
1023 */
1024int
1025nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
1026{
1027	struct llentry *lle;
1028	int rc = 0;
1029
1030	IF_AFDATA_UNLOCK_ASSERT(ifp);
1031	if (nd6_is_new_addr_neighbor(addr, ifp))
1032		return (1);
1033
1034	/*
1035	 * Even if the address matches none of our addresses, it might be
1036	 * in the neighbor cache.
1037	 */
1038	IF_AFDATA_RLOCK(ifp);
1039	if ((lle = nd6_lookup(&addr->sin6_addr, 0, ifp)) != NULL) {
1040		LLE_RUNLOCK(lle);
1041		rc = 1;
1042	}
1043	IF_AFDATA_RUNLOCK(ifp);
1044	return (rc);
1045}
1046
1047/*
1048 * Free an nd6 llinfo entry.
1049 * Since the function would cause significant changes in the kernel, DO NOT
1050 * make it global, unless you have a strong reason for the change, and are sure
1051 * that the change is safe.
1052 */
1053static struct llentry *
1054nd6_free(struct llentry *ln, int gc)
1055{
1056        struct llentry *next;
1057	struct nd_defrouter *dr;
1058	struct ifnet *ifp;
1059
1060	LLE_WLOCK_ASSERT(ln);
1061
1062	/*
1063	 * we used to have pfctlinput(PRC_HOSTDEAD) here.
1064	 * even though it is not harmful, it was not really necessary.
1065	 */
1066
1067	/* cancel timer */
1068	nd6_llinfo_settimer_locked(ln, -1);
1069
1070	ifp = ln->lle_tbl->llt_ifp;
1071
1072	if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
1073		dr = defrouter_lookup(&L3_ADDR_SIN6(ln)->sin6_addr, ifp);
1074
1075		if (dr != NULL && dr->expire &&
1076		    ln->ln_state == ND6_LLINFO_STALE && gc) {
1077			/*
1078			 * If the reason for the deletion is just garbage
1079			 * collection, and the neighbor is an active default
1080			 * router, do not delete it.  Instead, reset the GC
1081			 * timer using the router's lifetime.
1082			 * Simply deleting the entry would affect default
1083			 * router selection, which is not necessarily a good
1084			 * thing, especially when we're using router preference
1085			 * values.
1086			 * XXX: the check for ln_state would be redundant,
1087			 *      but we intentionally keep it just in case.
1088			 */
1089			if (dr->expire > time_uptime)
1090				nd6_llinfo_settimer_locked(ln,
1091				    (dr->expire - time_uptime) * hz);
1092			else
1093				nd6_llinfo_settimer_locked(ln,
1094				    (long)V_nd6_gctimer * hz);
1095
1096			next = LIST_NEXT(ln, lle_next);
1097			LLE_REMREF(ln);
1098			LLE_WUNLOCK(ln);
1099			return (next);
1100		}
1101
1102		if (dr) {
1103			/*
1104			 * Unreachablity of a router might affect the default
1105			 * router selection and on-link detection of advertised
1106			 * prefixes.
1107			 */
1108
1109			/*
1110			 * Temporarily fake the state to choose a new default
1111			 * router and to perform on-link determination of
1112			 * prefixes correctly.
1113			 * Below the state will be set correctly,
1114			 * or the entry itself will be deleted.
1115			 */
1116			ln->ln_state = ND6_LLINFO_INCOMPLETE;
1117		}
1118
1119		if (ln->ln_router || dr) {
1120
1121			/*
1122			 * We need to unlock to avoid a LOR with rt6_flush() with the
1123			 * rnh and for the calls to pfxlist_onlink_check() and
1124			 * defrouter_select() in the block further down for calls
1125			 * into nd6_lookup().  We still hold a ref.
1126			 */
1127			LLE_WUNLOCK(ln);
1128
1129			/*
1130			 * rt6_flush must be called whether or not the neighbor
1131			 * is in the Default Router List.
1132			 * See a corresponding comment in nd6_na_input().
1133			 */
1134			rt6_flush(&L3_ADDR_SIN6(ln)->sin6_addr, ifp);
1135		}
1136
1137		if (dr) {
1138			/*
1139			 * Since defrouter_select() does not affect the
1140			 * on-link determination and MIP6 needs the check
1141			 * before the default router selection, we perform
1142			 * the check now.
1143			 */
1144			pfxlist_onlink_check();
1145
1146			/*
1147			 * Refresh default router list.
1148			 */
1149			defrouter_select();
1150		}
1151
1152		if (ln->ln_router || dr)
1153			LLE_WLOCK(ln);
1154	}
1155
1156	/*
1157	 * Before deleting the entry, remember the next entry as the
1158	 * return value.  We need this because pfxlist_onlink_check() above
1159	 * might have freed other entries (particularly the old next entry) as
1160	 * a side effect (XXX).
1161	 */
1162	next = LIST_NEXT(ln, lle_next);
1163
1164	/*
1165	 * Save to unlock. We still hold an extra reference and will not
1166	 * free(9) in llentry_free() if someone else holds one as well.
1167	 */
1168	LLE_WUNLOCK(ln);
1169	IF_AFDATA_LOCK(ifp);
1170	LLE_WLOCK(ln);
1171
1172	/* Guard against race with other llentry_free(). */
1173	if (ln->la_flags & LLE_LINKED) {
1174		LLE_REMREF(ln);
1175		llentry_free(ln);
1176	} else
1177		LLE_FREE_LOCKED(ln);
1178
1179	IF_AFDATA_UNLOCK(ifp);
1180
1181	return (next);
1182}
1183
1184/*
1185 * Upper-layer reachability hint for Neighbor Unreachability Detection.
1186 *
1187 * XXX cost-effective methods?
1188 */
1189void
1190nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force)
1191{
1192	struct llentry *ln;
1193	struct ifnet *ifp;
1194
1195	if ((dst6 == NULL) || (rt == NULL))
1196		return;
1197
1198	ifp = rt->rt_ifp;
1199	IF_AFDATA_RLOCK(ifp);
1200	ln = nd6_lookup(dst6, ND6_EXCLUSIVE, NULL);
1201	IF_AFDATA_RUNLOCK(ifp);
1202	if (ln == NULL)
1203		return;
1204
1205	if (ln->ln_state < ND6_LLINFO_REACHABLE)
1206		goto done;
1207
1208	/*
1209	 * if we get upper-layer reachability confirmation many times,
1210	 * it is possible we have false information.
1211	 */
1212	if (!force) {
1213		ln->ln_byhint++;
1214		if (ln->ln_byhint > V_nd6_maxnudhint) {
1215			goto done;
1216		}
1217	}
1218
1219 	ln->ln_state = ND6_LLINFO_REACHABLE;
1220	if (!ND6_LLINFO_PERMANENT(ln)) {
1221		nd6_llinfo_settimer_locked(ln,
1222		    (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
1223	}
1224done:
1225	LLE_WUNLOCK(ln);
1226}
1227
1228
1229/*
1230 * Rejuvenate this function for routing operations related
1231 * processing.
1232 */
1233void
1234nd6_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
1235{
1236	struct sockaddr_in6 *gateway;
1237	struct nd_defrouter *dr;
1238	struct ifnet *ifp;
1239
1240	RT_LOCK_ASSERT(rt);
1241	gateway = (struct sockaddr_in6 *)rt->rt_gateway;
1242	ifp = rt->rt_ifp;
1243
1244	switch (req) {
1245	case RTM_ADD:
1246		break;
1247
1248	case RTM_DELETE:
1249		if (!ifp)
1250			return;
1251		/*
1252		 * Only indirect routes are interesting.
1253		 */
1254		if ((rt->rt_flags & RTF_GATEWAY) == 0)
1255			return;
1256		/*
1257		 * check for default route
1258		 */
1259		if (IN6_ARE_ADDR_EQUAL(&in6addr_any,
1260				       &SIN6(rt_key(rt))->sin6_addr)) {
1261
1262			dr = defrouter_lookup(&gateway->sin6_addr, ifp);
1263			if (dr != NULL)
1264				dr->installed = 0;
1265		}
1266		break;
1267	}
1268}
1269
1270
1271int
1272nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
1273{
1274	struct in6_ndireq *ndi = (struct in6_ndireq *)data;
1275	struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
1276	struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
1277	int error = 0;
1278
1279	if (ifp->if_afdata[AF_INET6] == NULL)
1280		return (EPFNOSUPPORT);
1281	switch (cmd) {
1282	case OSIOCGIFINFO_IN6:
1283#define ND	ndi->ndi
1284		/* XXX: old ndp(8) assumes a positive value for linkmtu. */
1285		bzero(&ND, sizeof(ND));
1286		ND.linkmtu = IN6_LINKMTU(ifp);
1287		ND.maxmtu = ND_IFINFO(ifp)->maxmtu;
1288		ND.basereachable = ND_IFINFO(ifp)->basereachable;
1289		ND.reachable = ND_IFINFO(ifp)->reachable;
1290		ND.retrans = ND_IFINFO(ifp)->retrans;
1291		ND.flags = ND_IFINFO(ifp)->flags;
1292		ND.recalctm = ND_IFINFO(ifp)->recalctm;
1293		ND.chlim = ND_IFINFO(ifp)->chlim;
1294		break;
1295	case SIOCGIFINFO_IN6:
1296		ND = *ND_IFINFO(ifp);
1297		break;
1298	case SIOCSIFINFO_IN6:
1299		/*
1300		 * used to change host variables from userland.
1301		 * intented for a use on router to reflect RA configurations.
1302		 */
1303		/* 0 means 'unspecified' */
1304		if (ND.linkmtu != 0) {
1305			if (ND.linkmtu < IPV6_MMTU ||
1306			    ND.linkmtu > IN6_LINKMTU(ifp)) {
1307				error = EINVAL;
1308				break;
1309			}
1310			ND_IFINFO(ifp)->linkmtu = ND.linkmtu;
1311		}
1312
1313		if (ND.basereachable != 0) {
1314			int obasereachable = ND_IFINFO(ifp)->basereachable;
1315
1316			ND_IFINFO(ifp)->basereachable = ND.basereachable;
1317			if (ND.basereachable != obasereachable)
1318				ND_IFINFO(ifp)->reachable =
1319				    ND_COMPUTE_RTIME(ND.basereachable);
1320		}
1321		if (ND.retrans != 0)
1322			ND_IFINFO(ifp)->retrans = ND.retrans;
1323		if (ND.chlim != 0)
1324			ND_IFINFO(ifp)->chlim = ND.chlim;
1325		/* FALLTHROUGH */
1326	case SIOCSIFINFO_FLAGS:
1327	{
1328		struct ifaddr *ifa;
1329		struct in6_ifaddr *ia;
1330
1331		if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
1332		    !(ND.flags & ND6_IFF_IFDISABLED)) {
1333			/* ifdisabled 1->0 transision */
1334
1335			/*
1336			 * If the interface is marked as ND6_IFF_IFDISABLED and
1337			 * has an link-local address with IN6_IFF_DUPLICATED,
1338			 * do not clear ND6_IFF_IFDISABLED.
1339			 * See RFC 4862, Section 5.4.5.
1340			 */
1341			IF_ADDR_RLOCK(ifp);
1342			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1343				if (ifa->ifa_addr->sa_family != AF_INET6)
1344					continue;
1345				ia = (struct in6_ifaddr *)ifa;
1346				if ((ia->ia6_flags & IN6_IFF_DUPLICATED) &&
1347				    IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia)))
1348					break;
1349			}
1350			IF_ADDR_RUNLOCK(ifp);
1351
1352			if (ifa != NULL) {
1353				/* LLA is duplicated. */
1354				ND.flags |= ND6_IFF_IFDISABLED;
1355				log(LOG_ERR, "Cannot enable an interface"
1356				    " with a link-local address marked"
1357				    " duplicate.\n");
1358			} else {
1359				ND_IFINFO(ifp)->flags &= ~ND6_IFF_IFDISABLED;
1360				if (ifp->if_flags & IFF_UP)
1361					in6_if_up(ifp);
1362			}
1363		} else if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
1364			    (ND.flags & ND6_IFF_IFDISABLED)) {
1365			/* ifdisabled 0->1 transision */
1366			/* Mark all IPv6 address as tentative. */
1367
1368			ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1369			if (V_ip6_dad_count > 0 &&
1370			    (ND_IFINFO(ifp)->flags & ND6_IFF_NO_DAD) == 0) {
1371				IF_ADDR_RLOCK(ifp);
1372				TAILQ_FOREACH(ifa, &ifp->if_addrhead,
1373				    ifa_link) {
1374					if (ifa->ifa_addr->sa_family !=
1375					    AF_INET6)
1376						continue;
1377					ia = (struct in6_ifaddr *)ifa;
1378					ia->ia6_flags |= IN6_IFF_TENTATIVE;
1379				}
1380				IF_ADDR_RUNLOCK(ifp);
1381			}
1382		}
1383
1384		if (ND.flags & ND6_IFF_AUTO_LINKLOCAL) {
1385			if (!(ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL)) {
1386				/* auto_linklocal 0->1 transision */
1387
1388				/* If no link-local address on ifp, configure */
1389				ND_IFINFO(ifp)->flags |= ND6_IFF_AUTO_LINKLOCAL;
1390				in6_ifattach(ifp, NULL);
1391			} else if (!(ND.flags & ND6_IFF_IFDISABLED) &&
1392			    ifp->if_flags & IFF_UP) {
1393				/*
1394				 * When the IF already has
1395				 * ND6_IFF_AUTO_LINKLOCAL, no link-local
1396				 * address is assigned, and IFF_UP, try to
1397				 * assign one.
1398				 */
1399				IF_ADDR_RLOCK(ifp);
1400				TAILQ_FOREACH(ifa, &ifp->if_addrhead,
1401				    ifa_link) {
1402					if (ifa->ifa_addr->sa_family !=
1403					    AF_INET6)
1404						continue;
1405					ia = (struct in6_ifaddr *)ifa;
1406					if (IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia)))
1407						break;
1408				}
1409				IF_ADDR_RUNLOCK(ifp);
1410				if (ifa != NULL)
1411					/* No LLA is configured. */
1412					in6_ifattach(ifp, NULL);
1413			}
1414		}
1415	}
1416		ND_IFINFO(ifp)->flags = ND.flags;
1417		break;
1418#undef ND
1419	case SIOCSNDFLUSH_IN6:	/* XXX: the ioctl name is confusing... */
1420		/* sync kernel routing table with the default router list */
1421		defrouter_reset();
1422		defrouter_select();
1423		break;
1424	case SIOCSPFXFLUSH_IN6:
1425	{
1426		/* flush all the prefix advertised by routers */
1427		struct nd_prefix *pr, *next;
1428
1429		LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) {
1430			struct in6_ifaddr *ia, *ia_next;
1431
1432			if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1433				continue; /* XXX */
1434
1435			/* do we really have to remove addresses as well? */
1436			/* XXXRW: in6_ifaddrhead locking. */
1437			TAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link,
1438			    ia_next) {
1439				if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1440					continue;
1441
1442				if (ia->ia6_ndpr == pr)
1443					in6_purgeaddr(&ia->ia_ifa);
1444			}
1445			prelist_remove(pr);
1446		}
1447		break;
1448	}
1449	case SIOCSRTRFLUSH_IN6:
1450	{
1451		/* flush all the default routers */
1452		struct nd_defrouter *dr, *next;
1453
1454		defrouter_reset();
1455		TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, next) {
1456			defrtrlist_del(dr);
1457		}
1458		defrouter_select();
1459		break;
1460	}
1461	case SIOCGNBRINFO_IN6:
1462	{
1463		struct llentry *ln;
1464		struct in6_addr nb_addr = nbi->addr; /* make local for safety */
1465
1466		if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0)
1467			return (error);
1468
1469		IF_AFDATA_RLOCK(ifp);
1470		ln = nd6_lookup(&nb_addr, 0, ifp);
1471		IF_AFDATA_RUNLOCK(ifp);
1472
1473		if (ln == NULL) {
1474			error = EINVAL;
1475			break;
1476		}
1477		nbi->state = ln->ln_state;
1478		nbi->asked = ln->la_asked;
1479		nbi->isrouter = ln->ln_router;
1480		if (ln->la_expire == 0)
1481			nbi->expire = 0;
1482		else
1483			nbi->expire = ln->la_expire +
1484			    (time_second - time_uptime);
1485		LLE_RUNLOCK(ln);
1486		break;
1487	}
1488	case SIOCGDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
1489		ndif->ifindex = V_nd6_defifindex;
1490		break;
1491	case SIOCSDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
1492		return (nd6_setdefaultiface(ndif->ifindex));
1493	}
1494	return (error);
1495}
1496
1497/*
1498 * Create neighbor cache entry and cache link-layer address,
1499 * on reception of inbound ND6 packets.  (RS/RA/NS/redirect)
1500 *
1501 * type - ICMP6 type
1502 * code - type dependent information
1503 *
1504 * XXXXX
1505 *  The caller of this function already acquired the ndp
1506 *  cache table lock because the cache entry is returned.
1507 */
1508struct llentry *
1509nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr,
1510    int lladdrlen, int type, int code)
1511{
1512	struct llentry *ln = NULL;
1513	int is_newentry;
1514	int do_update;
1515	int olladdr;
1516	int llchange;
1517	int flags;
1518	int newstate = 0;
1519	uint16_t router = 0;
1520	struct sockaddr_in6 sin6;
1521	struct mbuf *chain = NULL;
1522	int static_route = 0;
1523
1524	IF_AFDATA_UNLOCK_ASSERT(ifp);
1525
1526	KASSERT(ifp != NULL, ("%s: ifp == NULL", __func__));
1527	KASSERT(from != NULL, ("%s: from == NULL", __func__));
1528
1529	/* nothing must be updated for unspecified address */
1530	if (IN6_IS_ADDR_UNSPECIFIED(from))
1531		return NULL;
1532
1533	/*
1534	 * Validation about ifp->if_addrlen and lladdrlen must be done in
1535	 * the caller.
1536	 *
1537	 * XXX If the link does not have link-layer adderss, what should
1538	 * we do? (ifp->if_addrlen == 0)
1539	 * Spec says nothing in sections for RA, RS and NA.  There's small
1540	 * description on it in NS section (RFC 2461 7.2.3).
1541	 */
1542	flags = lladdr ? ND6_EXCLUSIVE : 0;
1543	IF_AFDATA_RLOCK(ifp);
1544	ln = nd6_lookup(from, flags, ifp);
1545	IF_AFDATA_RUNLOCK(ifp);
1546	if (ln == NULL) {
1547		flags |= ND6_EXCLUSIVE;
1548		IF_AFDATA_LOCK(ifp);
1549		ln = nd6_lookup(from, flags | ND6_CREATE, ifp);
1550		IF_AFDATA_UNLOCK(ifp);
1551		is_newentry = 1;
1552	} else {
1553		/* do nothing if static ndp is set */
1554		if (ln->la_flags & LLE_STATIC) {
1555			static_route = 1;
1556			goto done;
1557		}
1558		is_newentry = 0;
1559	}
1560	if (ln == NULL)
1561		return (NULL);
1562
1563	olladdr = (ln->la_flags & LLE_VALID) ? 1 : 0;
1564	if (olladdr && lladdr) {
1565		llchange = bcmp(lladdr, &ln->ll_addr,
1566		    ifp->if_addrlen);
1567	} else
1568		llchange = 0;
1569
1570	/*
1571	 * newentry olladdr  lladdr  llchange	(*=record)
1572	 *	0	n	n	--	(1)
1573	 *	0	y	n	--	(2)
1574	 *	0	n	y	--	(3) * STALE
1575	 *	0	y	y	n	(4) *
1576	 *	0	y	y	y	(5) * STALE
1577	 *	1	--	n	--	(6)   NOSTATE(= PASSIVE)
1578	 *	1	--	y	--	(7) * STALE
1579	 */
1580
1581	if (lladdr) {		/* (3-5) and (7) */
1582		/*
1583		 * Record source link-layer address
1584		 * XXX is it dependent to ifp->if_type?
1585		 */
1586		bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
1587		ln->la_flags |= LLE_VALID;
1588		EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED);
1589	}
1590
1591	if (!is_newentry) {
1592		if ((!olladdr && lladdr != NULL) ||	/* (3) */
1593		    (olladdr && lladdr != NULL && llchange)) {	/* (5) */
1594			do_update = 1;
1595			newstate = ND6_LLINFO_STALE;
1596		} else					/* (1-2,4) */
1597			do_update = 0;
1598	} else {
1599		do_update = 1;
1600		if (lladdr == NULL)			/* (6) */
1601			newstate = ND6_LLINFO_NOSTATE;
1602		else					/* (7) */
1603			newstate = ND6_LLINFO_STALE;
1604	}
1605
1606	if (do_update) {
1607		/*
1608		 * Update the state of the neighbor cache.
1609		 */
1610		ln->ln_state = newstate;
1611
1612		if (ln->ln_state == ND6_LLINFO_STALE) {
1613			if (ln->la_hold != NULL)
1614				nd6_grab_holdchain(ln, &chain, &sin6);
1615		} else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
1616			/* probe right away */
1617			nd6_llinfo_settimer_locked((void *)ln, 0);
1618		}
1619	}
1620
1621	/*
1622	 * ICMP6 type dependent behavior.
1623	 *
1624	 * NS: clear IsRouter if new entry
1625	 * RS: clear IsRouter
1626	 * RA: set IsRouter if there's lladdr
1627	 * redir: clear IsRouter if new entry
1628	 *
1629	 * RA case, (1):
1630	 * The spec says that we must set IsRouter in the following cases:
1631	 * - If lladdr exist, set IsRouter.  This means (1-5).
1632	 * - If it is old entry (!newentry), set IsRouter.  This means (7).
1633	 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1634	 * A quetion arises for (1) case.  (1) case has no lladdr in the
1635	 * neighbor cache, this is similar to (6).
1636	 * This case is rare but we figured that we MUST NOT set IsRouter.
1637	 *
1638	 * newentry olladdr  lladdr  llchange	    NS  RS  RA	redir
1639	 *							D R
1640	 *	0	n	n	--	(1)	c   ?     s
1641	 *	0	y	n	--	(2)	c   s     s
1642	 *	0	n	y	--	(3)	c   s     s
1643	 *	0	y	y	n	(4)	c   s     s
1644	 *	0	y	y	y	(5)	c   s     s
1645	 *	1	--	n	--	(6) c	c	c s
1646	 *	1	--	y	--	(7) c	c   s	c s
1647	 *
1648	 *					(c=clear s=set)
1649	 */
1650	switch (type & 0xff) {
1651	case ND_NEIGHBOR_SOLICIT:
1652		/*
1653		 * New entry must have is_router flag cleared.
1654		 */
1655		if (is_newentry)	/* (6-7) */
1656			ln->ln_router = 0;
1657		break;
1658	case ND_REDIRECT:
1659		/*
1660		 * If the icmp is a redirect to a better router, always set the
1661		 * is_router flag.  Otherwise, if the entry is newly created,
1662		 * clear the flag.  [RFC 2461, sec 8.3]
1663		 */
1664		if (code == ND_REDIRECT_ROUTER)
1665			ln->ln_router = 1;
1666		else if (is_newentry) /* (6-7) */
1667			ln->ln_router = 0;
1668		break;
1669	case ND_ROUTER_SOLICIT:
1670		/*
1671		 * is_router flag must always be cleared.
1672		 */
1673		ln->ln_router = 0;
1674		break;
1675	case ND_ROUTER_ADVERT:
1676		/*
1677		 * Mark an entry with lladdr as a router.
1678		 */
1679		if ((!is_newentry && (olladdr || lladdr)) ||	/* (2-5) */
1680		    (is_newentry && lladdr)) {			/* (7) */
1681			ln->ln_router = 1;
1682		}
1683		break;
1684	}
1685
1686	if (ln != NULL) {
1687		static_route = (ln->la_flags & LLE_STATIC);
1688		router = ln->ln_router;
1689
1690		if (flags & ND6_EXCLUSIVE)
1691			LLE_WUNLOCK(ln);
1692		else
1693			LLE_RUNLOCK(ln);
1694		if (static_route)
1695			ln = NULL;
1696	}
1697	if (chain != NULL)
1698		nd6_flush_holdchain(ifp, ifp, chain, &sin6);
1699
1700	/*
1701	 * When the link-layer address of a router changes, select the
1702	 * best router again.  In particular, when the neighbor entry is newly
1703	 * created, it might affect the selection policy.
1704	 * Question: can we restrict the first condition to the "is_newentry"
1705	 * case?
1706	 * XXX: when we hear an RA from a new router with the link-layer
1707	 * address option, defrouter_select() is called twice, since
1708	 * defrtrlist_update called the function as well.  However, I believe
1709	 * we can compromise the overhead, since it only happens the first
1710	 * time.
1711	 * XXX: although defrouter_select() should not have a bad effect
1712	 * for those are not autoconfigured hosts, we explicitly avoid such
1713	 * cases for safety.
1714	 */
1715	if (do_update && router &&
1716	    ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
1717		/*
1718		 * guaranteed recursion
1719		 */
1720		defrouter_select();
1721	}
1722
1723	return (ln);
1724done:
1725	if (ln != NULL) {
1726		if (flags & ND6_EXCLUSIVE)
1727			LLE_WUNLOCK(ln);
1728		else
1729			LLE_RUNLOCK(ln);
1730		if (static_route)
1731			ln = NULL;
1732	}
1733	return (ln);
1734}
1735
1736static void
1737nd6_slowtimo(void *arg)
1738{
1739	CURVNET_SET((struct vnet *) arg);
1740	struct nd_ifinfo *nd6if;
1741	struct ifnet *ifp;
1742
1743	callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
1744	    nd6_slowtimo, curvnet);
1745	IFNET_RLOCK_NOSLEEP();
1746	TAILQ_FOREACH(ifp, &V_ifnet, if_list) {
1747		if (ifp->if_afdata[AF_INET6] == NULL)
1748			continue;
1749		nd6if = ND_IFINFO(ifp);
1750		if (nd6if->basereachable && /* already initialized */
1751		    (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
1752			/*
1753			 * Since reachable time rarely changes by router
1754			 * advertisements, we SHOULD insure that a new random
1755			 * value gets recomputed at least once every few hours.
1756			 * (RFC 2461, 6.3.4)
1757			 */
1758			nd6if->recalctm = V_nd6_recalc_reachtm_interval;
1759			nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
1760		}
1761	}
1762	IFNET_RUNLOCK_NOSLEEP();
1763	CURVNET_RESTORE();
1764}
1765
1766void
1767nd6_grab_holdchain(struct llentry *ln, struct mbuf **chain,
1768    struct sockaddr_in6 *sin6)
1769{
1770
1771	LLE_WLOCK_ASSERT(ln);
1772
1773	*chain = ln->la_hold;
1774	ln->la_hold = NULL;
1775	memcpy(sin6, L3_ADDR_SIN6(ln), sizeof(*sin6));
1776
1777	if (ln->ln_state == ND6_LLINFO_STALE) {
1778
1779		/*
1780		 * The first time we send a packet to a
1781		 * neighbor whose entry is STALE, we have
1782		 * to change the state to DELAY and a sets
1783		 * a timer to expire in DELAY_FIRST_PROBE_TIME
1784		 * seconds to ensure do neighbor unreachability
1785		 * detection on expiration.
1786		 * (RFC 2461 7.3.3)
1787		 */
1788		ln->la_asked = 0;
1789		ln->ln_state = ND6_LLINFO_DELAY;
1790		nd6_llinfo_settimer_locked(ln, (long)V_nd6_delay * hz);
1791	}
1792}
1793
1794static int
1795nd6_output_ifp(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1796    struct sockaddr_in6 *dst)
1797{
1798	int error;
1799	int ip6len;
1800	struct ip6_hdr *ip6;
1801	struct m_tag *mtag;
1802
1803#ifdef MAC
1804	mac_netinet6_nd6_send(ifp, m);
1805#endif
1806
1807	/*
1808	 * If called from nd6_ns_output() (NS), nd6_na_output() (NA),
1809	 * icmp6_redirect_output() (REDIRECT) or from rip6_output() (RS, RA
1810	 * as handled by rtsol and rtadvd), mbufs will be tagged for SeND
1811	 * to be diverted to user space.  When re-injected into the kernel,
1812	 * send_output() will directly dispatch them to the outgoing interface.
1813	 */
1814	if (send_sendso_input_hook != NULL) {
1815		mtag = m_tag_find(m, PACKET_TAG_ND_OUTGOING, NULL);
1816		if (mtag != NULL) {
1817			ip6 = mtod(m, struct ip6_hdr *);
1818			ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
1819			/* Use the SEND socket */
1820			error = send_sendso_input_hook(m, ifp, SND_OUT,
1821			    ip6len);
1822			/* -1 == no app on SEND socket */
1823			if (error == 0 || error != -1)
1824			    return (error);
1825		}
1826	}
1827
1828	m_clrprotoflags(m);	/* Avoid confusing lower layers. */
1829	IP_PROBE(send, NULL, NULL, mtod(m, struct ip6_hdr *), ifp, NULL,
1830	    mtod(m, struct ip6_hdr *));
1831
1832	if ((ifp->if_flags & IFF_LOOPBACK) == 0)
1833		origifp = ifp;
1834
1835	error = (*ifp->if_output)(origifp, m, (struct sockaddr *)dst, NULL);
1836	return (error);
1837}
1838
1839/*
1840 * IPv6 packet output - light version.
1841 * Checks if destination LLE exists and is in proper state
1842 * (e.g no modification required). If not true, fall back to
1843 * "heavy" version.
1844 */
1845int
1846nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1847    struct sockaddr_in6 *dst, struct rtentry *rt0)
1848{
1849	struct llentry *ln = NULL;
1850
1851	/* discard the packet if IPv6 operation is disabled on the interface */
1852	if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) {
1853		m_freem(m);
1854		return (ENETDOWN); /* better error? */
1855	}
1856
1857	if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1858		goto sendpkt;
1859
1860	if (nd6_need_cache(ifp) == 0)
1861		goto sendpkt;
1862
1863	IF_AFDATA_RLOCK(ifp);
1864	ln = nd6_lookup(&dst->sin6_addr, 0, ifp);
1865	IF_AFDATA_RUNLOCK(ifp);
1866
1867	/*
1868	 * Perform fast path for the following cases:
1869	 * 1) lle state is REACHABLE
1870	 * 2) lle state is DELAY (NS message sentNS message sent)
1871	 *
1872	 * Every other case involves lle modification, so we handle
1873	 * them separately.
1874	 */
1875	if (ln == NULL || (ln->ln_state != ND6_LLINFO_REACHABLE &&
1876	    ln->ln_state != ND6_LLINFO_DELAY)) {
1877		/* Fall back to slow processing path */
1878		if (ln != NULL)
1879			LLE_RUNLOCK(ln);
1880		return (nd6_output_lle(ifp, origifp, m, dst));
1881	}
1882
1883sendpkt:
1884	if (ln != NULL)
1885		LLE_RUNLOCK(ln);
1886
1887	return (nd6_output_ifp(ifp, origifp, m, dst));
1888}
1889
1890
1891/*
1892 * Output IPv6 packet - heavy version.
1893 * Function assume that either
1894 * 1) destination LLE does not exist, is invalid or stale, so
1895 *   ND6_EXCLUSIVE lock needs to be acquired
1896 * 2) destination lle is provided (with ND6_EXCLUSIVE lock),
1897 *   in that case packets are queued in &chain.
1898 *
1899 */
1900static int
1901nd6_output_lle(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1902    struct sockaddr_in6 *dst)
1903{
1904	struct llentry *lle = NULL;
1905	int flags = 0;
1906
1907	KASSERT(m != NULL, ("NULL mbuf, nothing to send"));
1908	/* discard the packet if IPv6 operation is disabled on the interface */
1909	if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) {
1910		m_freem(m);
1911		return (ENETDOWN); /* better error? */
1912	}
1913
1914	if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1915		goto sendpkt;
1916
1917	if (nd6_need_cache(ifp) == 0)
1918		goto sendpkt;
1919
1920	/*
1921	 * Address resolution or Neighbor Unreachability Detection
1922	 * for the next hop.
1923	 * At this point, the destination of the packet must be a unicast
1924	 * or an anycast address(i.e. not a multicast).
1925	 */
1926	if (lle == NULL) {
1927		IF_AFDATA_RLOCK(ifp);
1928		lle = nd6_lookup(&dst->sin6_addr, ND6_EXCLUSIVE, ifp);
1929		IF_AFDATA_RUNLOCK(ifp);
1930		if ((lle == NULL) && nd6_is_addr_neighbor(dst, ifp))  {
1931			/*
1932			 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
1933			 * the condition below is not very efficient.  But we believe
1934			 * it is tolerable, because this should be a rare case.
1935			 */
1936			flags = ND6_CREATE | ND6_EXCLUSIVE;
1937			IF_AFDATA_LOCK(ifp);
1938			lle = nd6_lookup(&dst->sin6_addr, flags, ifp);
1939			IF_AFDATA_UNLOCK(ifp);
1940		}
1941	}
1942	if (lle == NULL) {
1943		if ((ifp->if_flags & IFF_POINTOPOINT) == 0 &&
1944		    !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) {
1945			char ip6buf[INET6_ADDRSTRLEN];
1946			log(LOG_DEBUG,
1947			    "nd6_output: can't allocate llinfo for %s "
1948			    "(ln=%p)\n",
1949			    ip6_sprintf(ip6buf, &dst->sin6_addr), lle);
1950			m_freem(m);
1951			return (ENOBUFS);
1952		}
1953		goto sendpkt;	/* send anyway */
1954	}
1955
1956	LLE_WLOCK_ASSERT(lle);
1957
1958	/* We don't have to do link-layer address resolution on a p2p link. */
1959	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
1960	    lle->ln_state < ND6_LLINFO_REACHABLE) {
1961		lle->ln_state = ND6_LLINFO_STALE;
1962		nd6_llinfo_settimer_locked(lle, (long)V_nd6_gctimer * hz);
1963	}
1964
1965	/*
1966	 * The first time we send a packet to a neighbor whose entry is
1967	 * STALE, we have to change the state to DELAY and a sets a timer to
1968	 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
1969	 * neighbor unreachability detection on expiration.
1970	 * (RFC 2461 7.3.3)
1971	 */
1972	if (lle->ln_state == ND6_LLINFO_STALE) {
1973		lle->la_asked = 0;
1974		lle->ln_state = ND6_LLINFO_DELAY;
1975		nd6_llinfo_settimer_locked(lle, (long)V_nd6_delay * hz);
1976	}
1977
1978	/*
1979	 * If the neighbor cache entry has a state other than INCOMPLETE
1980	 * (i.e. its link-layer address is already resolved), just
1981	 * send the packet.
1982	 */
1983	if (lle->ln_state > ND6_LLINFO_INCOMPLETE)
1984		goto sendpkt;
1985
1986	/*
1987	 * There is a neighbor cache entry, but no ethernet address
1988	 * response yet.  Append this latest packet to the end of the
1989	 * packet queue in the mbuf, unless the number of the packet
1990	 * does not exceed nd6_maxqueuelen.  When it exceeds nd6_maxqueuelen,
1991	 * the oldest packet in the queue will be removed.
1992	 */
1993	if (lle->ln_state == ND6_LLINFO_NOSTATE)
1994		lle->ln_state = ND6_LLINFO_INCOMPLETE;
1995
1996	if (lle->la_hold != NULL) {
1997		struct mbuf *m_hold;
1998		int i;
1999
2000		i = 0;
2001		for (m_hold = lle->la_hold; m_hold; m_hold = m_hold->m_nextpkt){
2002			i++;
2003			if (m_hold->m_nextpkt == NULL) {
2004				m_hold->m_nextpkt = m;
2005				break;
2006			}
2007		}
2008		while (i >= V_nd6_maxqueuelen) {
2009			m_hold = lle->la_hold;
2010			lle->la_hold = lle->la_hold->m_nextpkt;
2011			m_freem(m_hold);
2012			i--;
2013		}
2014	} else {
2015		lle->la_hold = m;
2016	}
2017
2018	/*
2019	 * If there has been no NS for the neighbor after entering the
2020	 * INCOMPLETE state, send the first solicitation.
2021	 */
2022	if (!ND6_LLINFO_PERMANENT(lle) && lle->la_asked == 0) {
2023		lle->la_asked++;
2024
2025		nd6_llinfo_settimer_locked(lle,
2026		    (long)ND_IFINFO(ifp)->retrans * hz / 1000);
2027		LLE_WUNLOCK(lle);
2028		nd6_ns_output(ifp, NULL, &dst->sin6_addr, lle, NULL);
2029	} else {
2030		/* We did the lookup so we need to do the unlock here. */
2031		LLE_WUNLOCK(lle);
2032	}
2033
2034	return (0);
2035
2036  sendpkt:
2037	if (lle != NULL)
2038		LLE_WUNLOCK(lle);
2039
2040	return (nd6_output_ifp(ifp, origifp, m, dst));
2041}
2042
2043
2044int
2045nd6_flush_holdchain(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *chain,
2046    struct sockaddr_in6 *dst)
2047{
2048	struct mbuf *m, *m_head;
2049	struct ifnet *outifp;
2050	int error = 0;
2051
2052	m_head = chain;
2053	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2054		outifp = origifp;
2055	else
2056		outifp = ifp;
2057
2058	while (m_head) {
2059		m = m_head;
2060		m_head = m_head->m_nextpkt;
2061		error = nd6_output_ifp(ifp, origifp, m, dst);
2062	}
2063
2064	/*
2065	 * XXX
2066	 * note that intermediate errors are blindly ignored - but this is
2067	 * the same convention as used with nd6_output when called by
2068	 * nd6_cache_lladdr
2069	 */
2070	return (error);
2071}
2072
2073
2074int
2075nd6_need_cache(struct ifnet *ifp)
2076{
2077	/*
2078	 * XXX: we currently do not make neighbor cache on any interface
2079	 * other than ARCnet, Ethernet, FDDI and GIF.
2080	 *
2081	 * RFC2893 says:
2082	 * - unidirectional tunnels needs no ND
2083	 */
2084	switch (ifp->if_type) {
2085	case IFT_ARCNET:
2086	case IFT_ETHER:
2087	case IFT_FDDI:
2088	case IFT_IEEE1394:
2089#ifdef IFT_L2VLAN
2090	case IFT_L2VLAN:
2091#endif
2092#ifdef IFT_IEEE80211
2093	case IFT_IEEE80211:
2094#endif
2095	case IFT_INFINIBAND:
2096	case IFT_BRIDGE:
2097	case IFT_PROPVIRTUAL:
2098		return (1);
2099	default:
2100		return (0);
2101	}
2102}
2103
2104/*
2105 * the callers of this function need to be re-worked to drop
2106 * the lle lock, drop here for now
2107 */
2108int
2109nd6_storelladdr(struct ifnet *ifp, struct mbuf *m,
2110    const struct sockaddr *dst, u_char *desten, struct llentry **lle)
2111{
2112	struct llentry *ln;
2113
2114	*lle = NULL;
2115	IF_AFDATA_UNLOCK_ASSERT(ifp);
2116	if (m != NULL && m->m_flags & M_MCAST) {
2117		int i;
2118
2119		switch (ifp->if_type) {
2120		case IFT_ETHER:
2121		case IFT_FDDI:
2122#ifdef IFT_L2VLAN
2123		case IFT_L2VLAN:
2124#endif
2125#ifdef IFT_IEEE80211
2126		case IFT_IEEE80211:
2127#endif
2128		case IFT_BRIDGE:
2129		case IFT_ISO88025:
2130			ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr,
2131						 desten);
2132			return (0);
2133		case IFT_IEEE1394:
2134			/*
2135			 * netbsd can use if_broadcastaddr, but we don't do so
2136			 * to reduce # of ifdef.
2137			 */
2138			for (i = 0; i < ifp->if_addrlen; i++)
2139				desten[i] = ~0;
2140			return (0);
2141		case IFT_ARCNET:
2142			*desten = 0;
2143			return (0);
2144		default:
2145			m_freem(m);
2146			return (EAFNOSUPPORT);
2147		}
2148	}
2149
2150
2151	/*
2152	 * the entry should have been created in nd6_store_lladdr
2153	 */
2154	IF_AFDATA_RLOCK(ifp);
2155	ln = lla_lookup(LLTABLE6(ifp), 0, dst);
2156	IF_AFDATA_RUNLOCK(ifp);
2157	if ((ln == NULL) || !(ln->la_flags & LLE_VALID)) {
2158		if (ln != NULL)
2159			LLE_RUNLOCK(ln);
2160		/* this could happen, if we could not allocate memory */
2161		m_freem(m);
2162		return (1);
2163	}
2164
2165	bcopy(&ln->ll_addr, desten, ifp->if_addrlen);
2166	*lle = ln;
2167	LLE_RUNLOCK(ln);
2168	/*
2169	 * A *small* use after free race exists here
2170	 */
2171	return (0);
2172}
2173
2174static void
2175clear_llinfo_pqueue(struct llentry *ln)
2176{
2177	struct mbuf *m_hold, *m_hold_next;
2178
2179	for (m_hold = ln->la_hold; m_hold; m_hold = m_hold_next) {
2180		m_hold_next = m_hold->m_nextpkt;
2181		m_freem(m_hold);
2182	}
2183
2184	ln->la_hold = NULL;
2185	return;
2186}
2187
2188static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
2189static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
2190#ifdef SYSCTL_DECL
2191SYSCTL_DECL(_net_inet6_icmp6);
2192#endif
2193SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2194	CTLFLAG_RD, nd6_sysctl_drlist, "");
2195SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
2196	CTLFLAG_RD, nd6_sysctl_prlist, "");
2197SYSCTL_VNET_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen,
2198	CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, "");
2199SYSCTL_VNET_INT(_net_inet6_icmp6, OID_AUTO, nd6_gctimer,
2200	CTLFLAG_RW, &VNET_NAME(nd6_gctimer), (60 * 60 * 24), "");
2201
2202static int
2203nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2204{
2205	struct in6_defrouter d;
2206	struct nd_defrouter *dr;
2207	int error;
2208
2209	if (req->newptr)
2210		return (EPERM);
2211
2212	bzero(&d, sizeof(d));
2213	d.rtaddr.sin6_family = AF_INET6;
2214	d.rtaddr.sin6_len = sizeof(d.rtaddr);
2215
2216	/*
2217	 * XXX locking
2218	 */
2219	TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
2220		d.rtaddr.sin6_addr = dr->rtaddr;
2221		error = sa6_recoverscope(&d.rtaddr);
2222		if (error != 0)
2223			return (error);
2224		d.flags = dr->flags;
2225		d.rtlifetime = dr->rtlifetime;
2226		d.expire = dr->expire + (time_second - time_uptime);
2227		d.if_index = dr->ifp->if_index;
2228		error = SYSCTL_OUT(req, &d, sizeof(d));
2229		if (error != 0)
2230			return (error);
2231	}
2232	return (0);
2233}
2234
2235static int
2236nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
2237{
2238	struct in6_prefix p;
2239	struct sockaddr_in6 s6;
2240	struct nd_prefix *pr;
2241	struct nd_pfxrouter *pfr;
2242	time_t maxexpire;
2243	int error;
2244	char ip6buf[INET6_ADDRSTRLEN];
2245
2246	if (req->newptr)
2247		return (EPERM);
2248
2249	bzero(&p, sizeof(p));
2250	p.origin = PR_ORIG_RA;
2251	bzero(&s6, sizeof(s6));
2252	s6.sin6_family = AF_INET6;
2253	s6.sin6_len = sizeof(s6);
2254
2255	/*
2256	 * XXX locking
2257	 */
2258	LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
2259		p.prefix = pr->ndpr_prefix;
2260		if (sa6_recoverscope(&p.prefix)) {
2261			log(LOG_ERR, "scope error in prefix list (%s)\n",
2262			    ip6_sprintf(ip6buf, &p.prefix.sin6_addr));
2263			/* XXX: press on... */
2264		}
2265		p.raflags = pr->ndpr_raf;
2266		p.prefixlen = pr->ndpr_plen;
2267		p.vltime = pr->ndpr_vltime;
2268		p.pltime = pr->ndpr_pltime;
2269		p.if_index = pr->ndpr_ifp->if_index;
2270		if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME)
2271			p.expire = 0;
2272		else {
2273			/* XXX: we assume time_t is signed. */
2274			maxexpire = (-1) &
2275			    ~((time_t)1 << ((sizeof(maxexpire) * 8) - 1));
2276			if (pr->ndpr_vltime < maxexpire - pr->ndpr_lastupdate)
2277				p.expire = pr->ndpr_lastupdate +
2278				    pr->ndpr_vltime +
2279				    (time_second - time_uptime);
2280			else
2281				p.expire = maxexpire;
2282		}
2283		p.refcnt = pr->ndpr_refcnt;
2284		p.flags = pr->ndpr_stateflags;
2285		p.advrtrs = 0;
2286		LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry)
2287			p.advrtrs++;
2288		error = SYSCTL_OUT(req, &p, sizeof(p));
2289		if (error != 0)
2290			return (error);
2291		LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) {
2292			s6.sin6_addr = pfr->router->rtaddr;
2293			if (sa6_recoverscope(&s6))
2294				log(LOG_ERR,
2295				    "scope error in prefix list (%s)\n",
2296				    ip6_sprintf(ip6buf, &pfr->router->rtaddr));
2297			error = SYSCTL_OUT(req, &s6, sizeof(s6));
2298			if (error != 0)
2299				return (error);
2300		}
2301	}
2302	return (0);
2303}
2304