1 /* $FreeBSD: src/sys/netinet6/nd6.c,v 1.2.2.15 2003/05/06 06:46:58 suz Exp $ */
2 /* $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $ */
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 #include "opt_inet6.h"
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/callout.h>
39 #include <sys/malloc.h>
41 #include <sys/socket.h>
42 #include <sys/sockio.h>
44 #include <sys/kernel.h>
45 #include <sys/protosw.h>
46 #include <sys/errno.h>
47 #include <sys/syslog.h>
48 #include <sys/queue.h>
49 #include <sys/sysctl.h>
50 #include <sys/mutex.h>
52 #include <sys/thread2.h>
53 #include <sys/mutex2.h>
56 #include <net/if_dl.h>
57 #include <net/if_types.h>
58 #include <net/route.h>
59 #include <net/netisr2.h>
60 #include <net/netmsg2.h>
62 #include <netinet/in.h>
63 #include <netinet/if_ether.h>
64 #include <netinet6/in6_var.h>
65 #include <netinet6/in6_ifattach.h>
66 #include <netinet/ip6.h>
67 #include <netinet6/ip6_var.h>
68 #include <netinet6/nd6.h>
69 #include <netinet/icmp6.h>
71 #include <net/net_osdep.h>
73 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
74 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
76 #define SIN6(s) ((struct sockaddr_in6 *)s)
77 #define SDL(s) ((struct sockaddr_dl *)s)
80 * Determine if the route entry is a direct neighbor on the specified
81 * interface. The interface test is not done if ifp is passed as NULL.
82 * The route entry is a neighbor if all of the following are true:
84 * RTF_GATEWAY is FALSE
86 * rt_gateway family is AF_LINK
87 * rt_llinfo is non-NULL
88 * The interfaces matches (or ifp is passed as NULL)
90 * NOTE: rt_llinfo can be NULL with LLINFO set, so both must be
93 * NOTE: We can't use rt->rt_ifp to check for the interface, since
94 * it may be the loopback interface if the entry is for our
95 * own address on a non-loopback interface. Instead, we use
96 * rt->rt_ifa->ifa_ifp which should specify the REAL interface.
98 #define ND6_IFP_MATCHES(ifp, ifa_ifp) \
100 (ifa_ifp) == (ifp) || \
101 (((ifp)->if_flags & IFF_ISBRIDGE) && \
102 (ifa_ifp)->if_bridge == (ifp)->if_softc) \
105 #define ND6_RTENTRY_IS_NEIGHBOR(rt, ifp) \
106 (((rt)->rt_flags & RTF_GATEWAY) == 0 && \
107 ((rt)->rt_flags & RTF_LLINFO) != 0 && \
108 (rt)->rt_gateway->sa_family == AF_LINK && \
110 ND6_IFP_MATCHES((ifp), (rt)->rt_ifa->ifa_ifp) \
113 #define ND6_RTENTRY_IS_LLCLONING(rt) \
114 (((rt)->rt_flags & (RTF_PRCLONING | RTF_LLINFO)) == \
115 (RTF_PRCLONING | RTF_LLINFO) || \
116 ((rt)->rt_flags & RTF_CLONING))
119 int nd6_prune
= 1; /* walk list every 1 seconds */
120 int nd6_delay
= 5; /* delay first probe time 5 second */
121 int nd6_umaxtries
= 3; /* maximum unicast query */
122 int nd6_mmaxtries
= 3; /* maximum multicast query */
123 int nd6_useloopback
= 1; /* use loopback interface for local traffic */
124 int nd6_gctimer
= (60 * 60 * 24); /* 1 day: garbage collection timer */
126 /* preventing too many loops in ND option parsing */
127 int nd6_maxndopt
= 10; /* max # of ND options allowed */
129 int nd6_maxnudhint
= 0; /* max # of subsequent upper layer hints */
138 static int nd6_inuse
, nd6_allocated
;
140 struct llinfo_nd6 llinfo_nd6
= {&llinfo_nd6
, &llinfo_nd6
};
141 struct nd_drhead nd_defrouter
;
142 struct nd_prhead nd_prefix
= { 0 };
143 struct mtx nd6_mtx
= MTX_INITIALIZER("nd6");
145 int nd6_recalc_reachtm_interval
= ND6_RECALC_REACHTM_INTERVAL
;
146 static struct sockaddr_in6 all1_sa
;
148 static void nd6_setmtu0 (struct ifnet
*, struct nd_ifinfo
*);
149 static int regen_tmpaddr (struct in6_ifaddr
*);
150 static void nd6_slowtimo(void *);
151 static void nd6_slowtimo_dispatch(netmsg_t
);
152 static void nd6_timer(void *);
153 static void nd6_timer_dispatch(netmsg_t
);
155 static struct callout nd6_slowtimo_ch
;
156 static struct netmsg_base nd6_slowtimo_netmsg
;
158 static struct callout nd6_timer_ch
;
159 static struct netmsg_base nd6_timer_netmsg
;
164 static int nd6_init_done
= 0;
168 log(LOG_NOTICE
, "nd6_init called more than once(ignored)\n");
172 all1_sa
.sin6_family
= AF_INET6
;
173 all1_sa
.sin6_len
= sizeof(struct sockaddr_in6
);
174 for (i
= 0; i
< sizeof(all1_sa
.sin6_addr
); i
++)
175 all1_sa
.sin6_addr
.s6_addr
[i
] = 0xff;
177 /* initialization of the default router list */
178 TAILQ_INIT(&nd_defrouter
);
183 callout_init_mp(&nd6_slowtimo_ch
);
184 netmsg_init(&nd6_slowtimo_netmsg
, NULL
, &netisr_adone_rport
,
185 MSGF_PRIORITY
, nd6_slowtimo_dispatch
);
186 callout_reset_bycpu(&nd6_slowtimo_ch
, ND6_SLOWTIMER_INTERVAL
* hz
,
187 nd6_slowtimo
, NULL
, 0);
191 nd6_ifattach(struct ifnet
*ifp
)
193 struct nd_ifinfo
*nd
;
195 nd
= kmalloc(sizeof(*nd
), M_IP6NDP
, M_WAITOK
| M_ZERO
);
199 nd
->chlim
= IPV6_DEFHLIM
;
200 nd
->basereachable
= REACHABLE_TIME
;
201 nd
->reachable
= ND_COMPUTE_RTIME(nd
->basereachable
);
202 nd
->retrans
= RETRANS_TIMER
;
204 nd
->flags
= ND6_IFF_PERFORMNUD
;
205 /* A loopback interface always has link-local address. */
206 if (ip6_auto_linklocal
|| (ifp
->if_flags
& IFF_LOOPBACK
))
207 nd
->flags
|= ND6_IFF_AUTO_LINKLOCAL
;
208 /* A loopback interface does not need to accept RAs. */
209 if (ip6_accept_rtadv
&& !(ifp
->if_flags
& IFF_LOOPBACK
))
210 nd
->flags
|= ND6_IFF_ACCEPT_RTADV
;
212 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
213 nd6_setmtu0(ifp
, nd
);
219 nd6_ifdetach(struct nd_ifinfo
*nd
)
225 * Reset ND level link MTU. This function is called when the physical MTU
226 * changes, which means we might have to adjust the ND level MTU.
229 nd6_setmtu(struct ifnet
*ifp
)
231 nd6_setmtu0(ifp
, ND_IFINFO(ifp
));
234 struct netmsg_nd6setmtu
{
235 struct netmsg_base nmsg
;
237 struct nd_ifinfo
*ndi
;
240 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
242 nd6_setmtu0_dispatch(netmsg_t msg
)
244 struct netmsg_nd6setmtu
*nmsg
= (struct netmsg_nd6setmtu
*)msg
;
245 struct ifnet
*ifp
= nmsg
->ifp
;
246 struct nd_ifinfo
*ndi
= nmsg
->ndi
;
249 omaxmtu
= ndi
->maxmtu
;
251 switch (ifp
->if_type
) {
253 ndi
->maxmtu
= MIN(ETHERMTU
, ifp
->if_mtu
);
255 case IFT_IEEE1394
: /* XXX should be IEEE1394MTU(1500) */
256 ndi
->maxmtu
= MIN(ETHERMTU
, ifp
->if_mtu
);
259 case IFT_IEEE80211
: /* XXX should be IEEE80211MTU(1500) */
260 ndi
->maxmtu
= MIN(ETHERMTU
, ifp
->if_mtu
);
264 ndi
->maxmtu
= ifp
->if_mtu
;
269 * Decreasing the interface MTU under IPV6 minimum MTU may cause
270 * undesirable situation. We thus notify the operator of the change
271 * explicitly. The check for omaxmtu is necessary to restrict the
272 * log to the case of changing the MTU, not initializing it.
274 if (omaxmtu
>= IPV6_MMTU
&& ndi
->maxmtu
< IPV6_MMTU
) {
275 log(LOG_NOTICE
, "nd6_setmtu0: "
276 "new link MTU on %s (%lu) is too small for IPv6\n",
277 if_name(ifp
), (unsigned long)ndi
->maxmtu
);
280 if (ndi
->maxmtu
> in6_maxmtu
)
281 in6_setmaxmtu(); /* check all interfaces just in case */
283 lwkt_replymsg(&nmsg
->nmsg
.lmsg
, 0);
287 nd6_setmtu0(struct ifnet
*ifp
, struct nd_ifinfo
*ndi
)
289 struct netmsg_nd6setmtu nmsg
;
291 netmsg_init(&nmsg
.nmsg
, NULL
, &curthread
->td_msgport
, 0,
292 nd6_setmtu0_dispatch
);
295 lwkt_domsg(netisr_cpuport(0), &nmsg
.nmsg
.lmsg
, 0);
299 nd6_option_init(void *opt
, int icmp6len
, union nd_opts
*ndopts
)
301 bzero(ndopts
, sizeof(*ndopts
));
302 ndopts
->nd_opts_search
= (struct nd_opt_hdr
*)opt
;
304 = (struct nd_opt_hdr
*)(((u_char
*)opt
) + icmp6len
);
307 ndopts
->nd_opts_done
= 1;
308 ndopts
->nd_opts_search
= NULL
;
313 * Take one ND option.
316 nd6_option(union nd_opts
*ndopts
)
318 struct nd_opt_hdr
*nd_opt
;
322 panic("ndopts == NULL in nd6_option");
323 if (!ndopts
->nd_opts_last
)
324 panic("uninitialized ndopts in nd6_option");
325 if (!ndopts
->nd_opts_search
)
327 if (ndopts
->nd_opts_done
)
330 nd_opt
= ndopts
->nd_opts_search
;
332 /* make sure nd_opt_len is inside the buffer */
333 if ((caddr_t
)&nd_opt
->nd_opt_len
>= (caddr_t
)ndopts
->nd_opts_last
) {
334 bzero(ndopts
, sizeof(*ndopts
));
338 olen
= nd_opt
->nd_opt_len
<< 3;
341 * Message validation requires that all included
342 * options have a length that is greater than zero.
344 bzero(ndopts
, sizeof(*ndopts
));
348 ndopts
->nd_opts_search
= (struct nd_opt_hdr
*)((caddr_t
)nd_opt
+ olen
);
349 if (ndopts
->nd_opts_search
> ndopts
->nd_opts_last
) {
350 /* option overruns the end of buffer, invalid */
351 bzero(ndopts
, sizeof(*ndopts
));
353 } else if (ndopts
->nd_opts_search
== ndopts
->nd_opts_last
) {
354 /* reached the end of options chain */
355 ndopts
->nd_opts_done
= 1;
356 ndopts
->nd_opts_search
= NULL
;
362 * Parse multiple ND options.
363 * This function is much easier to use, for ND routines that do not need
364 * multiple options of the same type.
367 nd6_options(union nd_opts
*ndopts
)
369 struct nd_opt_hdr
*nd_opt
;
373 panic("ndopts == NULL in nd6_options");
374 if (!ndopts
->nd_opts_last
)
375 panic("uninitialized ndopts in nd6_options");
376 if (!ndopts
->nd_opts_search
)
380 nd_opt
= nd6_option(ndopts
);
381 if (!nd_opt
&& !ndopts
->nd_opts_last
) {
383 * Message validation requires that all included
384 * options have a length that is greater than zero.
386 icmp6stat
.icp6s_nd_badopt
++;
387 bzero(ndopts
, sizeof(*ndopts
));
394 switch (nd_opt
->nd_opt_type
) {
395 case ND_OPT_SOURCE_LINKADDR
:
396 case ND_OPT_TARGET_LINKADDR
:
398 case ND_OPT_REDIRECTED_HEADER
:
399 if (ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
]) {
401 "duplicated ND6 option found (type=%d)\n",
402 nd_opt
->nd_opt_type
));
405 ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
]
409 case ND_OPT_PREFIX_INFORMATION
:
410 if (ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
] == 0) {
411 ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
]
414 ndopts
->nd_opts_pi_end
=
415 (struct nd_opt_prefix_info
*)nd_opt
;
419 * Unknown options must be silently ignored,
420 * to accomodate future extension to the protocol.
423 "nd6_options: unsupported option %d - "
424 "option ignored\n", nd_opt
->nd_opt_type
));
429 if (i
> nd6_maxndopt
) {
430 icmp6stat
.icp6s_nd_toomanyopt
++;
431 nd6log((LOG_INFO
, "too many loop in nd opt\n"));
435 if (ndopts
->nd_opts_done
)
443 * ND6 timer routine to expire default route list and prefix list
446 nd6_timer_dispatch(netmsg_t nmsg
)
448 struct llinfo_nd6
*ln
;
449 struct nd_defrouter
*dr
;
450 struct nd_prefix
*pr
;
452 struct in6_ifaddr
*ia6
, *nia6
;
457 lwkt_replymsg(&nmsg
->lmsg
, 0); /* reply ASAP */
462 ln
= llinfo_nd6
.ln_next
;
463 while (ln
&& ln
!= &llinfo_nd6
) {
465 struct sockaddr_in6
*dst
;
466 struct llinfo_nd6
*next
= ln
->ln_next
;
467 /* XXX: used for the DELAY case only: */
468 struct nd_ifinfo
*ndi
= NULL
;
470 if ((rt
= ln
->ln_rt
) == NULL
) {
474 if ((ifp
= rt
->rt_ifp
) == NULL
) {
478 ndi
= ND_IFINFO(ifp
);
479 dst
= (struct sockaddr_in6
*)rt_key(rt
);
481 if (ln
->ln_expire
> time_uptime
) {
488 panic("rt=0 in nd6_timer(ln=%p)", ln
);
489 if (rt
->rt_llinfo
&& (struct llinfo_nd6
*)rt
->rt_llinfo
!= ln
)
490 panic("rt_llinfo(%p) is not equal to ln(%p)",
493 panic("dst=0 in nd6_timer(ln=%p)", ln
);
495 switch (ln
->ln_state
) {
496 case ND6_LLINFO_WAITDELETE
:
499 case ND6_LLINFO_INCOMPLETE
:
500 if (ln
->ln_asked
++ >= nd6_mmaxtries
) {
501 struct mbuf
*m
= ln
->ln_hold
;
505 * Fake rcvif to make ICMP error
506 * more helpful in diagnosing
508 * XXX: should we consider
511 m
->m_pkthdr
.rcvif
= rt
->rt_ifp
;
515 * mbuf has empty MAC header, remove
516 * for icmp. XXX layer violation.
518 m_adj(m
, ETHER_HDR_LEN
);
519 icmp6_error(m
, ICMP6_DST_UNREACH
,
520 ICMP6_DST_UNREACH_ADDR
, 0);
523 ln
->ln_state
= ND6_LLINFO_WAITDELETE
;
524 rt_rtmsg(RTM_MISS
, rt
, rt
->rt_ifp
, 0);
526 ln
->ln_expire
= time_uptime
+
527 ND_IFINFO(ifp
)->retrans
/ 1000;
528 nd6_ns_output(ifp
, NULL
, &dst
->sin6_addr
,
531 case ND6_LLINFO_REACHABLE
:
533 ln
->ln_state
= ND6_LLINFO_STALE
;
534 ln
->ln_expire
= time_uptime
+ nd6_gctimer
;
538 case ND6_LLINFO_STALE
:
539 /* Garbage Collection(RFC 2461 5.3) */
544 case ND6_LLINFO_DELAY
:
545 if (ndi
&& (ndi
->flags
& ND6_IFF_PERFORMNUD
)) {
548 ln
->ln_state
= ND6_LLINFO_PROBE
;
549 ln
->ln_expire
= time_uptime
+
551 nd6_ns_output(ifp
, &dst
->sin6_addr
,
555 ln
->ln_state
= ND6_LLINFO_STALE
; /* XXX */
556 ln
->ln_expire
= time_uptime
+ nd6_gctimer
;
559 case ND6_LLINFO_PROBE
:
560 if (ln
->ln_asked
< nd6_umaxtries
) {
562 ln
->ln_expire
= time_uptime
+
563 ND_IFINFO(ifp
)->retrans
/ 1000;
564 nd6_ns_output(ifp
, &dst
->sin6_addr
,
565 &dst
->sin6_addr
, ln
, 0);
567 rt_rtmsg(RTM_MISS
, rt
, rt
->rt_ifp
, 0);
575 /* expire default router list */
576 dr
= TAILQ_FIRST(&nd_defrouter
);
578 if (dr
->expire
&& dr
->expire
< time_uptime
) {
579 struct nd_defrouter
*t
;
580 t
= TAILQ_NEXT(dr
, dr_entry
);
584 dr
= TAILQ_NEXT(dr
, dr_entry
);
589 * expire interface addresses.
590 * in the past the loop was inside prefix expiry processing.
591 * However, from a stricter speci-confrmance standpoint, we should
592 * rather separate address lifetimes and prefix lifetimes.
595 for (ia6
= in6_ifaddr
; ia6
; ia6
= nia6
) {
597 /* check address lifetime */
598 if (IFA6_IS_INVALID(ia6
)) {
602 * If the expiring address is temporary, try
603 * regenerating a new one. This would be useful when
604 * we suspended a laptop PC, then turned it on after a
605 * period that could invalidate all temporary
606 * addresses. Although we may have to restart the
607 * loop (see below), it must be after purging the
608 * address. Otherwise, we'd see an infinite loop of
611 if (ip6_use_tempaddr
&&
612 (ia6
->ia6_flags
& IN6_IFF_TEMPORARY
)) {
613 if (regen_tmpaddr(ia6
) == 0)
617 in6_purgeaddr(&ia6
->ia_ifa
);
620 goto addrloop
; /* XXX: see below */
621 /* ia6 is no longer good, continue on to next */
624 if (IFA6_IS_DEPRECATED(ia6
)) {
625 int oldflags
= ia6
->ia6_flags
;
627 if ((oldflags
& IN6_IFF_DEPRECATED
) == 0) {
628 ia6
->ia6_flags
|= IN6_IFF_DEPRECATED
;
629 in6_newaddrmsg((struct ifaddr
*)ia6
);
633 * If a temporary address has just become deprecated,
634 * regenerate a new one if possible.
636 if (ip6_use_tempaddr
&&
637 (ia6
->ia6_flags
& IN6_IFF_TEMPORARY
) &&
638 !(oldflags
& IN6_IFF_DEPRECATED
)) {
640 if (regen_tmpaddr(ia6
) == 0) {
642 * A new temporary address is
644 * XXX: this means the address chain
645 * has changed while we are still in
646 * the loop. Although the change
647 * would not cause disaster (because
648 * it's not a deletion, but an
649 * addition,) we'd rather restart the
650 * loop just for safety. Or does this
651 * significantly reduce performance??
658 * A new RA might have made a deprecated address
661 if (ia6
->ia6_flags
& IN6_IFF_DEPRECATED
) {
662 ia6
->ia6_flags
&= ~IN6_IFF_DEPRECATED
;
663 in6_newaddrmsg((struct ifaddr
*)ia6
);
668 /* expire prefix list */
669 pr
= nd_prefix
.lh_first
;
672 * check prefix lifetime.
673 * since pltime is just for autoconf, pltime processing for
674 * prefix is not necessary.
676 if (pr
->ndpr_expire
&& pr
->ndpr_expire
< time_uptime
) {
681 * address expiration and prefix expiration are
682 * separate. NEVER perform in6_purgeaddr here.
691 mtx_unlock(&nd6_mtx
);
693 callout_reset(&nd6_timer_ch
, nd6_prune
* hz
, nd6_timer
, NULL
);
697 nd6_timer(void *arg __unused
)
699 struct lwkt_msg
*lmsg
= &nd6_timer_netmsg
.lmsg
;
701 KASSERT(mycpuid
== 0, ("not on cpu0"));
703 if (lmsg
->ms_flags
& MSGF_DONE
)
704 lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg
);
711 callout_init_mp(&nd6_timer_ch
);
712 netmsg_init(&nd6_timer_netmsg
, NULL
, &netisr_adone_rport
,
713 MSGF_PRIORITY
, nd6_timer_dispatch
);
714 callout_reset_bycpu(&nd6_timer_ch
, hz
, nd6_timer
, NULL
, 0);
718 regen_tmpaddr(struct in6_ifaddr
*ia6
) /* deprecated/invalidated temporary
721 struct ifaddr_container
*ifac
;
723 struct in6_ifaddr
*public_ifa6
= NULL
;
725 ifp
= ia6
->ia_ifa
.ifa_ifp
;
726 TAILQ_FOREACH(ifac
, &ifp
->if_addrheads
[mycpuid
], ifa_link
) {
727 struct ifaddr
*ifa
= ifac
->ifa
;
728 struct in6_ifaddr
*it6
;
730 if (ifa
->ifa_addr
->sa_family
!= AF_INET6
)
733 it6
= (struct in6_ifaddr
*)ifa
;
735 /* ignore no autoconf addresses. */
736 if (!(it6
->ia6_flags
& IN6_IFF_AUTOCONF
))
739 /* ignore autoconf addresses with different prefixes. */
740 if (it6
->ia6_ndpr
== NULL
|| it6
->ia6_ndpr
!= ia6
->ia6_ndpr
)
744 * Now we are looking at an autoconf address with the same
745 * prefix as ours. If the address is temporary and is still
746 * preferred, do not create another one. It would be rare, but
747 * could happen, for example, when we resume a laptop PC after
750 if ((it6
->ia6_flags
& IN6_IFF_TEMPORARY
) &&
751 !IFA6_IS_DEPRECATED(it6
)) {
757 * This is a public autoconf address that has the same prefix
758 * as ours. If it is preferred, keep it. We can't break the
759 * loop here, because there may be a still-preferred temporary
760 * address with the prefix.
762 if (!IFA6_IS_DEPRECATED(it6
))
766 if (public_ifa6
!= NULL
) {
769 if ((e
= in6_tmpifadd(public_ifa6
, 0)) != 0) {
770 log(LOG_NOTICE
, "regen_tmpaddr: failed to create a new"
771 " tmp addr,errno=%d\n", e
);
781 * Nuke neighbor cache/prefix/default router management table, right before
785 nd6_purge(struct ifnet
*ifp
)
787 struct llinfo_nd6
*ln
, *nln
;
788 struct nd_defrouter
*dr
, *ndr
, drany
;
789 struct nd_prefix
*pr
, *npr
;
791 /* Nuke default router list entries toward ifp */
792 if ((dr
= TAILQ_FIRST(&nd_defrouter
)) != NULL
) {
794 * The first entry of the list may be stored in
795 * the routing table, so we'll delete it later.
797 for (dr
= TAILQ_NEXT(dr
, dr_entry
); dr
; dr
= ndr
) {
798 ndr
= TAILQ_NEXT(dr
, dr_entry
);
802 dr
= TAILQ_FIRST(&nd_defrouter
);
807 /* Nuke prefix list entries toward ifp */
808 for (pr
= nd_prefix
.lh_first
; pr
; pr
= npr
) {
810 if (pr
->ndpr_ifp
== ifp
) {
812 * Previously, pr->ndpr_addr is removed as well,
813 * but I strongly believe we don't have to do it.
814 * nd6_purge() is only called from in6_ifdetach(),
815 * which removes all the associated interface addresses
817 * (jinmei@kame.net 20010129)
823 /* cancel default outgoing interface setting */
824 if (nd6_defifindex
== ifp
->if_index
)
825 nd6_setdefaultiface(0);
827 if (!ip6_forwarding
&&
828 (ND_IFINFO(ifp
)->flags
& ND6_IFF_ACCEPT_RTADV
)) {
829 /* refresh default router list */
830 bzero(&drany
, sizeof(drany
));
831 defrouter_delreq(&drany
, 0);
836 * Nuke neighbor cache entries for the ifp.
837 * Note that rt->rt_ifp may not be the same as ifp,
838 * due to KAME goto ours hack. See RTM_RESOLVE case in
839 * nd6_rtrequest(), and ip6_input().
841 ln
= llinfo_nd6
.ln_next
;
842 while (ln
&& ln
!= &llinfo_nd6
) {
844 struct sockaddr_dl
*sdl
;
848 if (rt
&& rt
->rt_gateway
&&
849 rt
->rt_gateway
->sa_family
== AF_LINK
) {
850 sdl
= (struct sockaddr_dl
*)rt
->rt_gateway
;
851 if (sdl
->sdl_index
== ifp
->if_index
)
859 nd6_lookup(struct in6_addr
*addr6
, int create
, struct ifnet
*ifp
)
862 struct sockaddr_in6 sin6
;
864 bzero(&sin6
, sizeof(sin6
));
865 sin6
.sin6_len
= sizeof(struct sockaddr_in6
);
866 sin6
.sin6_family
= AF_INET6
;
867 sin6
.sin6_addr
= *addr6
;
870 rt
= rtlookup((struct sockaddr
*)&sin6
);
872 rt
= rtpurelookup((struct sockaddr
*)&sin6
);
873 if (rt
&& !(rt
->rt_flags
& RTF_LLINFO
)) {
875 * This is the case for the default route.
876 * If we want to create a neighbor cache for the address, we
877 * should free the route for the destination and allocate an
890 * If no route is available and create is set,
891 * we allocate a host route for the destination
892 * and treat it like an interface route.
893 * This hack is necessary for a neighbor which can't
894 * be covered by our own prefix.
898 ifa
= ifaof_ifpforaddr((struct sockaddr
*)&sin6
, ifp
);
903 * Create a new route. RTF_LLINFO is necessary
904 * to create a Neighbor Cache entry for the
905 * destination in nd6_rtrequest which will be
906 * called in rtrequest via ifa->ifa_rtrequest.
908 if ((e
= rtrequest(RTM_ADD
, (struct sockaddr
*)&sin6
,
909 ifa
->ifa_addr
, (struct sockaddr
*)&all1_sa
,
910 (ifa
->ifa_flags
| RTF_HOST
| RTF_LLINFO
) &
911 ~RTF_CLONING
, &rt
)) != 0) {
913 "nd6_lookup: failed to add route for a "
914 "neighbor(%s), errno=%d\n",
915 ip6_sprintf(addr6
), e
);
920 struct llinfo_nd6
*ln
=
921 (struct llinfo_nd6
*)rt
->rt_llinfo
;
923 ln
->ln_state
= ND6_LLINFO_NOSTATE
;
930 if (!ND6_RTENTRY_IS_NEIGHBOR(rt
, ifp
)) {
933 "nd6_lookup: failed to lookup %s (if = %s)\n",
934 ip6_sprintf(addr6
), ifp
? if_name(ifp
) : "unspec");
935 /* xxx more logs... kazu */
942 static struct rtentry
*
943 nd6_neighbor_lookup(struct in6_addr
*addr6
, struct ifnet
*ifp
)
946 struct sockaddr_in6 sin6
;
948 bzero(&sin6
, sizeof(sin6
));
949 sin6
.sin6_len
= sizeof(struct sockaddr_in6
);
950 sin6
.sin6_family
= AF_INET6
;
951 sin6
.sin6_addr
= *addr6
;
953 rt
= rtpurelookup((struct sockaddr
*)&sin6
);
958 if (!ND6_RTENTRY_IS_NEIGHBOR(rt
, ifp
)) {
959 if (nd6_onlink_ns_rfc4861
&&
960 (ND6_RTENTRY_IS_LLCLONING(rt
) || /* not cloned yet */
961 (rt
->rt_parent
!= NULL
&& /* cloning */
962 ND6_RTENTRY_IS_LLCLONING(rt
->rt_parent
)))) {
964 * If cloning ever happened or is happening,
965 * rtentry for addr6 would or will become a
976 * Detect if a given IPv6 address identifies a neighbor on a given link.
977 * XXX: should take care of the destination of a p2p link?
980 nd6_is_addr_neighbor(struct sockaddr_in6
*addr
, struct ifnet
*ifp
)
982 struct ifaddr_container
*ifac
;
985 #define IFADDR6(a) ((((struct in6_ifaddr *)(a))->ia_addr).sin6_addr)
986 #define IFMASK6(a) ((((struct in6_ifaddr *)(a))->ia_prefixmask).sin6_addr)
989 * A link-local address is always a neighbor.
990 * XXX: we should use the sin6_scope_id field rather than the embedded
993 if (IN6_IS_ADDR_LINKLOCAL(&addr
->sin6_addr
) &&
994 ntohs(*(u_int16_t
*)&addr
->sin6_addr
.s6_addr
[2]) == ifp
->if_index
)
998 * If the address matches one of our addresses,
999 * it should be a neighbor.
1001 TAILQ_FOREACH(ifac
, &ifp
->if_addrheads
[mycpuid
], ifa_link
) {
1002 struct ifaddr
*ifa
= ifac
->ifa
;
1004 if (ifa
->ifa_addr
->sa_family
!= AF_INET6
)
1007 for (i
= 0; i
< 4; i
++) {
1008 if ((IFADDR6(ifa
).s6_addr32
[i
] ^
1009 addr
->sin6_addr
.s6_addr32
[i
]) &
1010 IFMASK6(ifa
).s6_addr32
[i
])
1017 * Even if the address matches none of our addresses, it might be
1018 * in the neighbor cache.
1020 if (nd6_neighbor_lookup(&addr
->sin6_addr
, ifp
) != NULL
)
1029 * Free an nd6 llinfo entry.
1032 nd6_free(struct rtentry
*rt
)
1034 struct llinfo_nd6
*ln
= (struct llinfo_nd6
*)rt
->rt_llinfo
, *next
;
1035 struct in6_addr in6
= ((struct sockaddr_in6
*)rt_key(rt
))->sin6_addr
;
1036 struct nd_defrouter
*dr
;
1039 * we used to have kpfctlinput(PRC_HOSTDEAD) here.
1040 * even though it is not harmful, it was not really necessary.
1043 /* XXX: this condition too restrictive? */
1044 if (!ip6_forwarding
&&
1045 (ND_IFINFO(rt
->rt_ifp
)->flags
& ND6_IFF_ACCEPT_RTADV
)) {
1047 dr
= defrouter_lookup(
1048 &((struct sockaddr_in6
*)rt_key(rt
))->sin6_addr
,
1051 if (ln
->ln_router
|| dr
) {
1053 * rt6_flush must be called whether or not the neighbor
1054 * is in the Default Router List.
1055 * See a corresponding comment in nd6_na_input().
1057 rt6_flush(&in6
, rt
->rt_ifp
);
1062 * Unreachablity of a router might affect the default
1063 * router selection and on-link detection of advertised
1068 * Temporarily fake the state to choose a new default
1069 * router and to perform on-link determination of
1070 * prefixes correctly.
1071 * Below the state will be set correctly,
1072 * or the entry itself will be deleted.
1074 ln
->ln_state
= ND6_LLINFO_INCOMPLETE
;
1077 * Since defrouter_select() does not affect the
1078 * on-link determination and MIP6 needs the check
1079 * before the default router selection, we perform
1082 pfxlist_onlink_check();
1084 if (dr
== TAILQ_FIRST(&nd_defrouter
)) {
1086 * It is used as the current default router,
1087 * so we have to move it to the end of the
1088 * list and choose a new one.
1089 * XXX: it is not very efficient if this is
1092 TAILQ_REMOVE(&nd_defrouter
, dr
, dr_entry
);
1093 TAILQ_INSERT_TAIL(&nd_defrouter
, dr
, dr_entry
);
1098 mtx_unlock(&nd6_mtx
);
1102 * Before deleting the entry, remember the next entry as the
1103 * return value. We need this because pfxlist_onlink_check() above
1104 * might have freed other entries (particularly the old next entry) as
1105 * a side effect (XXX).
1110 * Detach the route from the routing tree and the list of neighbor
1111 * caches, and disable the route entry not to be used in already
1114 * ND expiry happens under one big timer.
1115 * To avoid overflowing the route socket, don't report this.
1116 * Now that RTM_MISS is reported when an address is unresolvable
1117 * the benefit of reporting this deletion is questionable.
1119 rtrequest(RTM_DELETE
, rt_key(rt
), NULL
, rt_mask(rt
), 0, NULL
);
1125 * Upper-layer reachability hint for Neighbor Unreachability Detection.
1127 * XXX cost-effective metods?
1130 nd6_nud_hint(struct rtentry
*rt
, struct in6_addr
*dst6
, int force
)
1132 struct llinfo_nd6
*ln
;
1135 * If the caller specified "rt", use that. Otherwise, resolve the
1136 * routing table by supplied "dst6".
1141 if (!(rt
= nd6_lookup(dst6
, 0, NULL
)))
1145 if ((rt
->rt_flags
& RTF_GATEWAY
) ||
1146 !(rt
->rt_flags
& RTF_LLINFO
) ||
1147 rt
->rt_llinfo
== NULL
|| rt
->rt_gateway
== NULL
||
1148 rt
->rt_gateway
->sa_family
!= AF_LINK
) {
1149 /* This is not a host route. */
1153 ln
= (struct llinfo_nd6
*)rt
->rt_llinfo
;
1154 if (ln
->ln_state
< ND6_LLINFO_REACHABLE
)
1158 * if we get upper-layer reachability confirmation many times,
1159 * it is possible we have false information.
1163 if (ln
->ln_byhint
> nd6_maxnudhint
)
1167 ln
->ln_state
= ND6_LLINFO_REACHABLE
;
1169 ln
->ln_expire
= time_uptime
+
1170 ND_IFINFO(rt
->rt_ifp
)->reachable
;
1174 nd6_rtrequest(int req
, struct rtentry
*rt
)
1176 struct sockaddr
*gate
= rt
->rt_gateway
;
1177 struct llinfo_nd6
*ln
= (struct llinfo_nd6
*)rt
->rt_llinfo
;
1178 static struct sockaddr_dl null_sdl
= {sizeof(null_sdl
), AF_LINK
};
1179 struct ifnet
*ifp
= rt
->rt_ifp
;
1182 if ((rt
->rt_flags
& RTF_GATEWAY
))
1185 if (nd6_need_cache(ifp
) == 0 && !(rt
->rt_flags
& RTF_HOST
)) {
1187 * This is probably an interface direct route for a link
1188 * which does not need neighbor caches (e.g. fe80::%lo0/64).
1189 * We do not need special treatment below for such a route.
1190 * Moreover, the RTF_LLINFO flag which would be set below
1191 * would annoy the ndp(8) command.
1196 if (req
== RTM_RESOLVE
&&
1197 (nd6_need_cache(ifp
) == 0 || /* stf case */
1198 !nd6_is_addr_neighbor((struct sockaddr_in6
*)rt_key(rt
), ifp
))) {
1200 * FreeBSD and BSD/OS often make a cloned host route based
1201 * on a less-specific route (e.g. the default route).
1202 * If the less specific route does not have a "gateway"
1203 * (this is the case when the route just goes to a p2p or an
1204 * stf interface), we'll mistakenly make a neighbor cache for
1205 * the host route, and will see strange neighbor solicitation
1206 * for the corresponding destination. In order to avoid the
1207 * confusion, we check if the destination of the route is
1208 * a neighbor in terms of neighbor discovery, and stop the
1209 * process if not. Additionally, we remove the LLINFO flag
1210 * so that ndp(8) will not try to get the neighbor information
1211 * of the destination.
1213 rt
->rt_flags
&= ~RTF_LLINFO
;
1220 * There is no backward compatibility :)
1222 * if (!(rt->rt_flags & RTF_HOST) &&
1223 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
1224 * rt->rt_flags |= RTF_CLONING;
1226 if (rt
->rt_flags
& (RTF_CLONING
| RTF_LLINFO
)) {
1228 * Case 1: This route should come from
1229 * a route to interface. RTF_LLINFO flag is set
1230 * for a host route whose destination should be
1231 * treated as on-link.
1233 rt_setgate(rt
, rt_key(rt
),
1234 (struct sockaddr
*)&null_sdl
);
1235 gate
= rt
->rt_gateway
;
1236 SDL(gate
)->sdl_type
= ifp
->if_type
;
1237 SDL(gate
)->sdl_index
= ifp
->if_index
;
1239 ln
->ln_expire
= time_uptime
;
1240 if (ln
&& ln
->ln_expire
== 0) {
1241 /* kludge for desktops */
1244 if ((rt
->rt_flags
& RTF_CLONING
))
1248 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here.
1249 * We don't do that here since llinfo is not ready yet.
1251 * There are also couple of other things to be discussed:
1252 * - unsolicited NA code needs improvement beforehand
1253 * - RFC2461 says we MAY send multicast unsolicited NA
1254 * (7.2.6 paragraph 4), however, it also says that we
1255 * SHOULD provide a mechanism to prevent multicast NA storm.
1256 * we don't have anything like it right now.
1257 * note that the mechanism needs a mutual agreement
1258 * between proxies, which means that we need to implement
1259 * a new protocol, or a new kludge.
1260 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA.
1261 * we need to check ip6forwarding before sending it.
1262 * (or should we allow proxy ND configuration only for
1263 * routers? there's no mention about proxy ND from hosts)
1266 /* XXX it does not work */
1267 if ((rt
->rt_flags
& RTF_ANNOUNCE
) && mycpuid
== 0) {
1269 &SIN6(rt_key(rt
))->sin6_addr
,
1270 &SIN6(rt_key(rt
))->sin6_addr
,
1271 ip6_forwarding
? ND_NA_FLAG_ROUTER
: 0,
1277 if ((ifp
->if_flags
& (IFF_POINTOPOINT
| IFF_LOOPBACK
)) == 0) {
1279 * Address resolution isn't necessary for a point to
1280 * point link, so we can skip this test for a p2p link.
1282 if (gate
->sa_family
!= AF_LINK
||
1283 gate
->sa_len
< sizeof(null_sdl
)) {
1285 "nd6_rtrequest: bad gateway value: %s\n",
1289 SDL(gate
)->sdl_type
= ifp
->if_type
;
1290 SDL(gate
)->sdl_index
= ifp
->if_index
;
1293 break; /* This happens on a route change */
1295 * Case 2: This route may come from cloning, or a manual route
1296 * add with a LL address.
1298 R_Malloc(ln
, struct llinfo_nd6
*, sizeof(*ln
));
1299 rt
->rt_llinfo
= (caddr_t
)ln
;
1301 log(LOG_DEBUG
, "nd6_rtrequest: malloc failed\n");
1306 bzero(ln
, sizeof(*ln
));
1308 /* this is required for "ndp" command. - shin */
1309 if (req
== RTM_ADD
) {
1311 * gate should have some valid AF_LINK entry,
1312 * and ln->ln_expire should have some lifetime
1313 * which is specified by ndp command.
1315 ln
->ln_state
= ND6_LLINFO_REACHABLE
;
1319 * When req == RTM_RESOLVE, rt is created and
1320 * initialized in rtrequest(), so rt_expire is 0.
1322 ln
->ln_state
= ND6_LLINFO_NOSTATE
;
1323 ln
->ln_expire
= time_uptime
;
1325 rt
->rt_flags
|= RTF_LLINFO
;
1326 ln
->ln_next
= llinfo_nd6
.ln_next
;
1327 llinfo_nd6
.ln_next
= ln
;
1328 ln
->ln_prev
= &llinfo_nd6
;
1329 ln
->ln_next
->ln_prev
= ln
;
1332 * check if rt_key(rt) is one of my address assigned
1335 ifa
= (struct ifaddr
*)in6ifa_ifpwithaddr(rt
->rt_ifp
,
1336 &SIN6(rt_key(rt
))->sin6_addr
);
1338 caddr_t macp
= nd6_ifptomac(ifp
);
1340 ln
->ln_state
= ND6_LLINFO_REACHABLE
;
1343 bcopy(macp
, LLADDR(SDL(gate
)), ifp
->if_addrlen
);
1344 SDL(gate
)->sdl_alen
= ifp
->if_addrlen
;
1346 if (nd6_useloopback
) {
1347 rt
->rt_ifp
= loif
; /* XXX */
1349 * Make sure rt_ifa be equal to the ifaddr
1350 * corresponding to the address.
1351 * We need this because when we refer
1352 * rt_ifa->ia6_flags in ip6_input, we assume
1353 * that the rt_ifa points to the address instead
1354 * of the loopback address.
1356 if (ifa
!= rt
->rt_ifa
) {
1357 IFAFREE(rt
->rt_ifa
);
1362 } else if (rt
->rt_flags
& RTF_ANNOUNCE
) {
1364 ln
->ln_state
= ND6_LLINFO_REACHABLE
;
1368 * Join solicited node multicast for proxy ND, and only
1369 * join it once on cpu0.
1371 if ((ifp
->if_flags
& IFF_MULTICAST
) && mycpuid
== 0) {
1372 struct in6_addr llsol
;
1375 llsol
= SIN6(rt_key(rt
))->sin6_addr
;
1376 llsol
.s6_addr16
[0] = htons(0xff02);
1377 llsol
.s6_addr16
[1] = htons(ifp
->if_index
);
1378 llsol
.s6_addr32
[1] = 0;
1379 llsol
.s6_addr32
[2] = htonl(1);
1380 llsol
.s6_addr8
[12] = 0xff;
1382 if (!in6_addmulti(&llsol
, ifp
, &error
)) {
1383 nd6log((LOG_ERR
, "%s: failed to join "
1384 "%s (errno=%d)\n", if_name(ifp
),
1385 ip6_sprintf(&llsol
), error
));
1395 * Leave from solicited node multicast for proxy ND, and only
1396 * leave it once on cpu0 (since we joined it once on cpu0).
1398 if ((rt
->rt_flags
& RTF_ANNOUNCE
) &&
1399 (ifp
->if_flags
& IFF_MULTICAST
) && mycpuid
== 0) {
1400 struct in6_addr llsol
;
1401 struct in6_multi
*in6m
;
1403 llsol
= SIN6(rt_key(rt
))->sin6_addr
;
1404 llsol
.s6_addr16
[0] = htons(0xff02);
1405 llsol
.s6_addr16
[1] = htons(ifp
->if_index
);
1406 llsol
.s6_addr32
[1] = 0;
1407 llsol
.s6_addr32
[2] = htonl(1);
1408 llsol
.s6_addr8
[12] = 0xff;
1410 in6m
= IN6_LOOKUP_MULTI(&llsol
, ifp
);
1415 ln
->ln_next
->ln_prev
= ln
->ln_prev
;
1416 ln
->ln_prev
->ln_next
= ln
->ln_next
;
1419 rt
->rt_flags
&= ~RTF_LLINFO
;
1421 m_freem(ln
->ln_hold
);
1427 nd6_ioctl(u_long cmd
, caddr_t data
, struct ifnet
*ifp
)
1429 struct in6_drlist
*drl
= (struct in6_drlist
*)data
;
1430 struct in6_prlist
*prl
= (struct in6_prlist
*)data
;
1431 struct in6_ndireq
*ndi
= (struct in6_ndireq
*)data
;
1432 struct in6_nbrinfo
*nbi
= (struct in6_nbrinfo
*)data
;
1433 struct in6_ndifreq
*ndif
= (struct in6_ndifreq
*)data
;
1434 struct nd_defrouter
*dr
, any
;
1435 struct nd_prefix
*pr
;
1437 int i
= 0, error
= 0;
1440 case SIOCGDRLST_IN6
:
1442 * obsolete API, use sysctl under net.inet6.icmp6
1444 bzero(drl
, sizeof(*drl
));
1446 dr
= TAILQ_FIRST(&nd_defrouter
);
1447 while (dr
&& i
< DRLSTSIZ
) {
1448 drl
->defrouter
[i
].rtaddr
= dr
->rtaddr
;
1449 if (IN6_IS_ADDR_LINKLOCAL(&drl
->defrouter
[i
].rtaddr
)) {
1450 /* XXX: need to this hack for KAME stack */
1451 drl
->defrouter
[i
].rtaddr
.s6_addr16
[1] = 0;
1454 "default router list contains a "
1455 "non-linklocal address(%s)\n",
1456 ip6_sprintf(&drl
->defrouter
[i
].rtaddr
));
1458 drl
->defrouter
[i
].flags
= dr
->flags
;
1459 drl
->defrouter
[i
].rtlifetime
= dr
->rtlifetime
;
1460 drl
->defrouter
[i
].expire
= dr
->expire
;
1461 drl
->defrouter
[i
].if_index
= dr
->ifp
->if_index
;
1463 dr
= TAILQ_NEXT(dr
, dr_entry
);
1465 mtx_unlock(&nd6_mtx
);
1467 case SIOCGPRLST_IN6
:
1469 * obsolete API, use sysctl under net.inet6.icmp6
1472 * XXX meaning of fields, especialy "raflags", is very
1473 * differnet between RA prefix list and RR/static prefix list.
1474 * how about separating ioctls into two?
1476 bzero(prl
, sizeof(*prl
));
1478 pr
= nd_prefix
.lh_first
;
1479 while (pr
&& i
< PRLSTSIZ
) {
1480 struct nd_pfxrouter
*pfr
;
1483 in6_embedscope(&prl
->prefix
[i
].prefix
,
1484 &pr
->ndpr_prefix
, NULL
, NULL
);
1485 prl
->prefix
[i
].raflags
= pr
->ndpr_raf
;
1486 prl
->prefix
[i
].prefixlen
= pr
->ndpr_plen
;
1487 prl
->prefix
[i
].vltime
= pr
->ndpr_vltime
;
1488 prl
->prefix
[i
].pltime
= pr
->ndpr_pltime
;
1489 prl
->prefix
[i
].if_index
= pr
->ndpr_ifp
->if_index
;
1490 prl
->prefix
[i
].expire
= pr
->ndpr_expire
;
1492 pfr
= pr
->ndpr_advrtrs
.lh_first
;
1496 #define RTRADDR prl->prefix[i].advrtr[j]
1497 RTRADDR
= pfr
->router
->rtaddr
;
1498 if (IN6_IS_ADDR_LINKLOCAL(&RTRADDR
)) {
1499 /* XXX: hack for KAME */
1500 RTRADDR
.s6_addr16
[1] = 0;
1503 "a router(%s) advertises "
1505 "non-link local address\n",
1506 ip6_sprintf(&RTRADDR
));
1510 pfr
= pfr
->pfr_next
;
1512 prl
->prefix
[i
].advrtrs
= j
;
1513 prl
->prefix
[i
].origin
= PR_ORIG_RA
;
1518 mtx_unlock(&nd6_mtx
);
1521 case OSIOCGIFINFO_IN6
:
1522 /* XXX: old ndp(8) assumes a positive value for linkmtu. */
1523 bzero(&ndi
->ndi
, sizeof(ndi
->ndi
));
1524 ndi
->ndi
.linkmtu
= IN6_LINKMTU(ifp
);
1525 ndi
->ndi
.maxmtu
= ND_IFINFO(ifp
)->maxmtu
;
1526 ndi
->ndi
.basereachable
= ND_IFINFO(ifp
)->basereachable
;
1527 ndi
->ndi
.reachable
= ND_IFINFO(ifp
)->reachable
;
1528 ndi
->ndi
.retrans
= ND_IFINFO(ifp
)->retrans
;
1529 ndi
->ndi
.flags
= ND_IFINFO(ifp
)->flags
;
1530 ndi
->ndi
.recalctm
= ND_IFINFO(ifp
)->recalctm
;
1531 ndi
->ndi
.chlim
= ND_IFINFO(ifp
)->chlim
;
1533 case SIOCGIFINFO_IN6
:
1534 ndi
->ndi
= *ND_IFINFO(ifp
);
1535 ndi
->ndi
.linkmtu
= IN6_LINKMTU(ifp
);
1537 case SIOCSIFINFO_IN6
:
1539 * used to change host variables from userland.
1540 * intented for a use on router to reflect RA configurations.
1542 /* 0 means 'unspecified' */
1543 if (ndi
->ndi
.linkmtu
!= 0) {
1544 if (ndi
->ndi
.linkmtu
< IPV6_MMTU
||
1545 ndi
->ndi
.linkmtu
> IN6_LINKMTU(ifp
)) {
1549 ND_IFINFO(ifp
)->linkmtu
= ndi
->ndi
.linkmtu
;
1552 if (ndi
->ndi
.basereachable
!= 0) {
1553 int obasereachable
= ND_IFINFO(ifp
)->basereachable
;
1555 ND_IFINFO(ifp
)->basereachable
= ndi
->ndi
.basereachable
;
1556 if (ndi
->ndi
.basereachable
!= obasereachable
)
1557 ND_IFINFO(ifp
)->reachable
=
1558 ND_COMPUTE_RTIME(ndi
->ndi
.basereachable
);
1560 if (ndi
->ndi
.retrans
!= 0)
1561 ND_IFINFO(ifp
)->retrans
= ndi
->ndi
.retrans
;
1562 if (ndi
->ndi
.chlim
!= 0)
1563 ND_IFINFO(ifp
)->chlim
= ndi
->ndi
.chlim
;
1565 case SIOCSIFINFO_FLAGS
:
1566 if ((ndi
->ndi
.flags
& ND6_IFF_AUTO_LINKLOCAL
) &&
1567 !(ND_IFINFO(ifp
)->flags
& ND6_IFF_AUTO_LINKLOCAL
)) {
1568 /* auto_linklocal 0->1 transision */
1569 ND_IFINFO(ifp
)->flags
|= ND6_IFF_AUTO_LINKLOCAL
;
1570 in6_ifattach(ifp
, NULL
);
1572 ND_IFINFO(ifp
)->flags
= ndi
->ndi
.flags
;
1574 case SIOCSNDFLUSH_IN6
: /* XXX: the ioctl name is confusing... */
1575 /* flush default router list */
1577 * xxx sumikawa: should not delete route if default
1578 * route equals to the top of default router list
1580 bzero(&any
, sizeof(any
));
1581 defrouter_delreq(&any
, 0);
1583 /* xxx sumikawa: flush prefix list */
1585 case SIOCSPFXFLUSH_IN6
:
1587 /* flush all the prefix advertised by routers */
1588 struct nd_prefix
*pr
, *next
;
1591 for (pr
= nd_prefix
.lh_first
; pr
; pr
= next
) {
1592 struct in6_ifaddr
*ia
, *ia_next
;
1594 next
= pr
->ndpr_next
;
1596 if (IN6_IS_ADDR_LINKLOCAL(&pr
->ndpr_prefix
.sin6_addr
))
1599 /* do we really have to remove addresses as well? */
1600 for (ia
= in6_ifaddr
; ia
; ia
= ia_next
) {
1601 /* ia might be removed. keep the next ptr. */
1602 ia_next
= ia
->ia_next
;
1604 if (!(ia
->ia6_flags
& IN6_IFF_AUTOCONF
))
1607 if (ia
->ia6_ndpr
== pr
)
1608 in6_purgeaddr(&ia
->ia_ifa
);
1612 mtx_unlock(&nd6_mtx
);
1615 case SIOCSRTRFLUSH_IN6
:
1617 /* flush all the default routers */
1618 struct nd_defrouter
*dr
, *next
;
1621 if ((dr
= TAILQ_FIRST(&nd_defrouter
)) != NULL
) {
1623 * The first entry of the list may be stored in
1624 * the routing table, so we'll delete it later.
1626 for (dr
= TAILQ_NEXT(dr
, dr_entry
); dr
; dr
= next
) {
1627 next
= TAILQ_NEXT(dr
, dr_entry
);
1630 defrtrlist_del(TAILQ_FIRST(&nd_defrouter
));
1632 mtx_unlock(&nd6_mtx
);
1635 case SIOCGNBRINFO_IN6
:
1637 struct llinfo_nd6
*ln
;
1638 struct in6_addr nb_addr
= nbi
->addr
; /* make local for safety */
1641 * XXX: KAME specific hack for scoped addresses
1642 * XXXX: for other scopes than link-local?
1644 if (IN6_IS_ADDR_LINKLOCAL(&nbi
->addr
) ||
1645 IN6_IS_ADDR_MC_LINKLOCAL(&nbi
->addr
)) {
1646 u_int16_t
*idp
= (u_int16_t
*)&nb_addr
.s6_addr
[2];
1649 *idp
= htons(ifp
->if_index
);
1653 if ((rt
= nd6_lookup(&nb_addr
, 0, ifp
)) == NULL
) {
1655 mtx_unlock(&nd6_mtx
);
1658 ln
= (struct llinfo_nd6
*)rt
->rt_llinfo
;
1659 nbi
->state
= ln
->ln_state
;
1660 nbi
->asked
= ln
->ln_asked
;
1661 nbi
->isrouter
= ln
->ln_router
;
1662 nbi
->expire
= ln
->ln_expire
;
1663 mtx_unlock(&nd6_mtx
);
1667 case SIOCGDEFIFACE_IN6
: /* XXX: should be implemented as a sysctl? */
1668 ndif
->ifindex
= nd6_defifindex
;
1670 case SIOCSDEFIFACE_IN6
: /* XXX: should be implemented as a sysctl? */
1671 return (nd6_setdefaultiface(ndif
->ifindex
));
1677 * Create neighbor cache entry and cache link-layer address,
1678 * on reception of inbound ND6 packets. (RS/RA/NS/redirect)
1681 nd6_cache_lladdr(struct ifnet
*ifp
, struct in6_addr
*from
, char *lladdr
,
1683 int type
, /* ICMP6 type */
1684 int code
/* type dependent information */)
1686 struct rtentry
*rt
= NULL
;
1687 struct llinfo_nd6
*ln
= NULL
;
1689 struct sockaddr_dl
*sdl
= NULL
;
1696 panic("ifp == NULL in nd6_cache_lladdr");
1698 panic("from == NULL in nd6_cache_lladdr");
1700 /* nothing must be updated for unspecified address */
1701 if (IN6_IS_ADDR_UNSPECIFIED(from
))
1705 * Validation about ifp->if_addrlen and lladdrlen must be done in
1708 * XXX If the link does not have link-layer adderss, what should
1709 * we do? (ifp->if_addrlen == 0)
1710 * Spec says nothing in sections for RA, RS and NA. There's small
1711 * description on it in NS section (RFC 2461 7.2.3).
1714 rt
= nd6_lookup(from
, 0, ifp
);
1717 /* nothing must be done if there's no lladdr */
1718 if (!lladdr
|| !lladdrlen
)
1722 rt
= nd6_lookup(from
, 1, ifp
);
1725 /* do nothing if static ndp is set */
1726 if (rt
->rt_flags
& RTF_STATIC
)
1733 if ((rt
->rt_flags
& (RTF_GATEWAY
| RTF_LLINFO
)) != RTF_LLINFO
) {
1738 ln
= (struct llinfo_nd6
*)rt
->rt_llinfo
;
1741 if (!rt
->rt_gateway
)
1743 if (rt
->rt_gateway
->sa_family
!= AF_LINK
)
1745 sdl
= SDL(rt
->rt_gateway
);
1747 olladdr
= (sdl
->sdl_alen
) ? 1 : 0;
1748 if (olladdr
&& lladdr
) {
1749 if (bcmp(lladdr
, LLADDR(sdl
), ifp
->if_addrlen
))
1757 * newentry olladdr lladdr llchange (*=record)
1760 * 0 n y -- (3) * STALE
1762 * 0 y y y (5) * STALE
1763 * 1 -- n -- (6) NOSTATE(= PASSIVE)
1764 * 1 -- y -- (7) * STALE
1767 if (lladdr
) { /* (3-5) and (7) */
1769 * Record source link-layer address
1770 * XXX is it dependent to ifp->if_type?
1772 sdl
->sdl_alen
= ifp
->if_addrlen
;
1773 bcopy(lladdr
, LLADDR(sdl
), ifp
->if_addrlen
);
1777 if ((!olladdr
&& lladdr
) || /* (3) */
1778 (olladdr
&& lladdr
&& llchange
)) { /* (5) */
1780 newstate
= ND6_LLINFO_STALE
;
1781 } else { /* (1-2,4) */
1786 if (!lladdr
) /* (6) */
1787 newstate
= ND6_LLINFO_NOSTATE
;
1789 newstate
= ND6_LLINFO_STALE
;
1794 * Update the state of the neighbor cache.
1796 ln
->ln_state
= newstate
;
1798 if (ln
->ln_state
== ND6_LLINFO_STALE
) {
1800 * XXX: since nd6_output() below will cause
1801 * state tansition to DELAY and reset the timer,
1802 * we must set the timer now, although it is actually
1805 ln
->ln_expire
= time_uptime
+ nd6_gctimer
;
1809 * we assume ifp is not a p2p here, so just
1810 * set the 2nd argument as the 1st one.
1812 nd6_output(ifp
, ifp
, ln
->ln_hold
,
1813 (struct sockaddr_in6
*)rt_key(rt
), rt
);
1816 } else if (ln
->ln_state
== ND6_LLINFO_INCOMPLETE
) {
1817 /* probe right away */
1818 ln
->ln_expire
= time_uptime
;
1823 * ICMP6 type dependent behavior.
1825 * NS: clear IsRouter if new entry
1826 * RS: clear IsRouter
1827 * RA: set IsRouter if there's lladdr
1828 * redir: clear IsRouter if new entry
1831 * The spec says that we must set IsRouter in the following cases:
1832 * - If lladdr exist, set IsRouter. This means (1-5).
1833 * - If it is old entry (!newentry), set IsRouter. This means (7).
1834 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1835 * A quetion arises for (1) case. (1) case has no lladdr in the
1836 * neighbor cache, this is similar to (6).
1837 * This case is rare but we figured that we MUST NOT set IsRouter.
1839 * newentry olladdr lladdr llchange NS RS RA redir
1841 * 0 n n -- (1) c ? s
1842 * 0 y n -- (2) c s s
1843 * 0 n y -- (3) c s s
1846 * 1 -- n -- (6) c c c s
1847 * 1 -- y -- (7) c c s c s
1851 switch (type
& 0xff) {
1852 case ND_NEIGHBOR_SOLICIT
:
1854 * New entry must have is_router flag cleared.
1856 if (is_newentry
) /* (6-7) */
1861 * If the icmp is a redirect to a better router, always set the
1862 * is_router flag. Otherwise, if the entry is newly created,
1863 * clear the flag. [RFC 2461, sec 8.3]
1865 if (code
== ND_REDIRECT_ROUTER
)
1867 else if (is_newentry
) /* (6-7) */
1870 case ND_ROUTER_SOLICIT
:
1872 * is_router flag must always be cleared.
1876 case ND_ROUTER_ADVERT
:
1878 * Mark an entry with lladdr as a router.
1880 if ((!is_newentry
&& (olladdr
|| lladdr
)) || /* (2-5) */
1881 (is_newentry
&& lladdr
)) { /* (7) */
1887 if (llchange
|| lladdr
)
1888 rt_rtmsg(llchange
? RTM_CHANGE
: RTM_ADD
, rt
, rt
->rt_ifp
, 0);
1891 * When the link-layer address of a router changes, select the
1892 * best router again. In particular, when the neighbor entry is newly
1893 * created, it might affect the selection policy.
1894 * Question: can we restrict the first condition to the "is_newentry"
1896 * XXX: when we hear an RA from a new router with the link-layer
1897 * address option, defrouter_select() is called twice, since
1898 * defrtrlist_update called the function as well. However, I believe
1899 * we can compromise the overhead, since it only happens the first
1901 * XXX: although defrouter_select() should not have a bad effect
1902 * for those are not autoconfigured hosts, we explicitly avoid such
1905 if (do_update
&& ln
->ln_router
&& !ip6_forwarding
&&
1906 (ND_IFINFO(ifp
)->flags
& ND6_IFF_ACCEPT_RTADV
))
1913 nd6_slowtimo(void *arg __unused
)
1915 struct lwkt_msg
*lmsg
= &nd6_slowtimo_netmsg
.lmsg
;
1917 KASSERT(mycpuid
== 0, ("not on cpu0"));
1919 if (lmsg
->ms_flags
& MSGF_DONE
)
1920 lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg
);
1925 nd6_slowtimo_dispatch(netmsg_t nmsg
)
1927 const struct ifnet_array
*arr
;
1928 struct nd_ifinfo
*nd6if
;
1934 lwkt_replymsg(&nmsg
->lmsg
, 0); /* reply ASAP */
1937 arr
= ifnet_array_get();
1940 for (i
= 0; i
< arr
->ifnet_count
; ++i
) {
1941 struct ifnet
*ifp
= arr
->ifnet_arr
[i
];
1943 if (ifp
->if_afdata
[AF_INET6
] == NULL
)
1945 nd6if
= ND_IFINFO(ifp
);
1946 if (nd6if
->basereachable
&& /* already initialized */
1947 (nd6if
->recalctm
-= ND6_SLOWTIMER_INTERVAL
) <= 0) {
1949 * Since reachable time rarely changes by router
1950 * advertisements, we SHOULD insure that a new random
1951 * value gets recomputed at least once every few hours.
1954 nd6if
->recalctm
= nd6_recalc_reachtm_interval
;
1955 nd6if
->reachable
= ND_COMPUTE_RTIME(nd6if
->basereachable
);
1958 mtx_unlock(&nd6_mtx
);
1960 callout_reset(&nd6_slowtimo_ch
, ND6_SLOWTIMER_INTERVAL
* hz
,
1961 nd6_slowtimo
, NULL
);
1965 nd6_output(struct ifnet
*ifp
, struct ifnet
*origifp
, struct mbuf
*m
,
1966 struct sockaddr_in6
*dst
, struct rtentry
*rt
)
1970 if (ifp
->if_flags
& IFF_LOOPBACK
)
1971 error
= ifp
->if_output(origifp
, m
, (struct sockaddr
*)dst
, rt
);
1973 error
= ifp
->if_output(ifp
, m
, (struct sockaddr
*)dst
, rt
);
1978 nd6_resolve(struct ifnet
*ifp
, struct rtentry
*rt0
, struct mbuf
*m
,
1979 struct sockaddr
*dst0
, u_char
*desten
)
1981 struct sockaddr_in6
*dst
= SIN6(dst0
);
1982 struct rtentry
*rt
= NULL
;
1983 struct llinfo_nd6
*ln
= NULL
;
1986 if (m
->m_flags
& M_MCAST
) {
1987 switch (ifp
->if_type
) {
1992 #ifdef IFT_IEEE80211
1995 ETHER_MAP_IPV6_MULTICAST(&dst
->sin6_addr
,
1999 bcopy(ifp
->if_broadcastaddr
, desten
, ifp
->if_addrlen
);
2002 error
= EAFNOSUPPORT
;
2008 error
= rt_llroute(dst0
, rt0
, &rt
);
2015 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
2016 * the condition below is not very efficient. But we believe
2017 * it is tolerable, because this should be a rare case.
2019 if (ln
== NULL
&& nd6_is_addr_neighbor(dst
, ifp
)) {
2020 rt
= nd6_lookup(&dst
->sin6_addr
, 1, ifp
);
2025 if (ln
== NULL
|| rt
== NULL
) {
2026 if (!(ifp
->if_flags
& IFF_POINTOPOINT
) &&
2027 !(ND_IFINFO(ifp
)->flags
& ND6_IFF_PERFORMNUD
)) {
2029 "nd6_output: can't allocate llinfo for %s "
2031 ip6_sprintf(&dst
->sin6_addr
), ln
, rt
);
2038 /* We don't have to do link-layer address resolution on a p2p link. */
2039 if ((ifp
->if_flags
& IFF_POINTOPOINT
) &&
2040 ln
->ln_state
< ND6_LLINFO_REACHABLE
) {
2041 ln
->ln_state
= ND6_LLINFO_STALE
;
2042 ln
->ln_expire
= time_uptime
+ nd6_gctimer
;
2046 * The first time we send a packet to a neighbor whose entry is
2047 * STALE, we have to change the state to DELAY and a sets a timer to
2048 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
2049 * neighbor unreachability detection on expiration.
2052 if (ln
->ln_state
== ND6_LLINFO_STALE
) {
2054 ln
->ln_state
= ND6_LLINFO_DELAY
;
2055 ln
->ln_expire
= time_uptime
+ nd6_delay
;
2059 * If the neighbor cache entry has a state other than INCOMPLETE
2060 * (i.e. its link-layer address is already resolved), return it.
2062 if (ln
->ln_state
> ND6_LLINFO_INCOMPLETE
) {
2063 struct sockaddr_dl
*sdl
= SDL(rt
->rt_gateway
);
2065 KKASSERT(sdl
->sdl_family
== AF_LINK
&& sdl
->sdl_alen
!= 0);
2066 bcopy(LLADDR(sdl
), desten
, sdl
->sdl_alen
);
2071 * There is a neighbor cache entry, but no ethernet address
2072 * response yet. Replace the held mbuf (if any) with this
2076 m_freem(ln
->ln_hold
);
2080 * This code conforms to the rate-limiting rule described in Section
2081 * 7.2.2 of RFC 2461, because the timer is set correctly after sending
2084 if (ln
->ln_state
== ND6_LLINFO_NOSTATE
||
2085 ln
->ln_state
== ND6_LLINFO_WAITDELETE
) {
2087 * This neighbor cache entry was just created; change its
2088 * state to INCOMPLETE and start its life cycle.
2090 * We force an NS output below by setting ln_expire to 1
2091 * (nd6_rtrequest() could set it to the current time_uptime)
2092 * and zeroing out ln_asked (XXX this may not be necessary).
2094 ln
->ln_state
= ND6_LLINFO_INCOMPLETE
;
2098 if (ln
->ln_expire
&& ln
->ln_expire
< time_uptime
&& ln
->ln_asked
== 0) {
2100 ln
->ln_expire
= time_uptime
+ ND_IFINFO(ifp
)->retrans
/ 1000;
2101 nd6_ns_output(ifp
, NULL
, &dst
->sin6_addr
, ln
, 0);
2104 if (ln
->ln_asked
>= nd6_mmaxtries
)
2105 return (rt
!= NULL
&& rt
->rt_flags
& RTF_GATEWAY
) ?
2106 EHOSTUNREACH
: EHOSTDOWN
;
2115 nd6_need_cache(struct ifnet
*ifp
)
2118 * XXX: we currently do not make neighbor cache on any interface
2119 * other than Ethernet and GIF.
2122 * - unidirectional tunnels needs no ND
2124 switch (ifp
->if_type
) {
2130 #ifdef IFT_IEEE80211
2136 case IFT_GIF
: /* XXX need more cases? */
2143 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS
);
2144 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS
);
2146 SYSCTL_DECL(_net_inet6_icmp6
);
2148 SYSCTL_NODE(_net_inet6_icmp6
, ICMPV6CTL_ND6_DRLIST
, nd6_drlist
,
2149 CTLFLAG_RD
, nd6_sysctl_drlist
, "List default routers");
2150 SYSCTL_NODE(_net_inet6_icmp6
, ICMPV6CTL_ND6_PRLIST
, nd6_prlist
,
2151 CTLFLAG_RD
, nd6_sysctl_prlist
, "List prefixes");
2154 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS
)
2158 struct in6_defrouter
*d
, *de
;
2159 struct nd_defrouter
*dr
;
2165 for (dr
= TAILQ_FIRST(&nd_defrouter
); dr
;
2166 dr
= TAILQ_NEXT(dr
, dr_entry
)) {
2167 d
= (struct in6_defrouter
*)buf
;
2168 de
= (struct in6_defrouter
*)(buf
+ sizeof(buf
));
2171 bzero(d
, sizeof(*d
));
2172 d
->rtaddr
.sin6_family
= AF_INET6
;
2173 d
->rtaddr
.sin6_len
= sizeof(d
->rtaddr
);
2174 if (in6_recoverscope(&d
->rtaddr
, &dr
->rtaddr
,
2178 "default router list (%s)\n",
2179 ip6_sprintf(&dr
->rtaddr
));
2180 d
->flags
= dr
->flags
;
2181 d
->rtlifetime
= dr
->rtlifetime
;
2182 d
->expire
= dr
->expire
;
2183 d
->if_index
= dr
->ifp
->if_index
;
2185 panic("buffer too short");
2187 error
= SYSCTL_OUT(req
, buf
, sizeof(*d
));
2195 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS
)
2199 struct in6_prefix
*p
, *pe
;
2200 struct nd_prefix
*pr
;
2206 for (pr
= nd_prefix
.lh_first
; pr
; pr
= pr
->ndpr_next
) {
2209 struct sockaddr_in6
*sin6
, *s6
;
2210 struct nd_pfxrouter
*pfr
;
2212 p
= (struct in6_prefix
*)buf
;
2213 pe
= (struct in6_prefix
*)(buf
+ sizeof(buf
));
2216 bzero(p
, sizeof(*p
));
2217 sin6
= (struct sockaddr_in6
*)(p
+ 1);
2219 p
->prefix
= pr
->ndpr_prefix
;
2220 if (in6_recoverscope(&p
->prefix
,
2221 &p
->prefix
.sin6_addr
, pr
->ndpr_ifp
) != 0)
2223 "scope error in prefix list (%s)\n",
2224 ip6_sprintf(&p
->prefix
.sin6_addr
));
2225 p
->raflags
= pr
->ndpr_raf
;
2226 p
->prefixlen
= pr
->ndpr_plen
;
2227 p
->vltime
= pr
->ndpr_vltime
;
2228 p
->pltime
= pr
->ndpr_pltime
;
2229 p
->if_index
= pr
->ndpr_ifp
->if_index
;
2230 p
->expire
= pr
->ndpr_expire
;
2231 p
->refcnt
= pr
->ndpr_refcnt
;
2232 p
->flags
= pr
->ndpr_stateflags
;
2233 p
->origin
= PR_ORIG_RA
;
2235 for (pfr
= pr
->ndpr_advrtrs
.lh_first
; pfr
;
2236 pfr
= pfr
->pfr_next
) {
2237 if ((void *)&sin6
[advrtrs
+ 1] > (void *)pe
) {
2241 s6
= &sin6
[advrtrs
];
2242 bzero(s6
, sizeof(*s6
));
2243 s6
->sin6_family
= AF_INET6
;
2244 s6
->sin6_len
= sizeof(*sin6
);
2245 if (in6_recoverscope(s6
, &pfr
->router
->rtaddr
,
2246 pfr
->router
->ifp
) != 0)
2249 "prefix list (%s)\n",
2250 ip6_sprintf(&pfr
->router
->rtaddr
));
2253 p
->advrtrs
= advrtrs
;
2255 panic("buffer too short");
2258 advance
= sizeof(*p
) + sizeof(*sin6
) * advrtrs
;
2259 error
= SYSCTL_OUT(req
, buf
, advance
);