1 /* $FreeBSD: src/sys/netinet6/nd6.c,v 1.2.2.15 2003/05/06 06:46:58 suz Exp $ */
2 /* $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $ */
3
4 /*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/callout.h>
39 #include <sys/malloc.h>
40 #include <sys/mbuf.h>
41 #include <sys/socket.h>
42 #include <sys/sockio.h>
43 #include <sys/time.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>
51
52 #include <sys/thread2.h>
53 #include <sys/mutex2.h>
54
55 #include <net/if.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>
61
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>
70
71 #include <net/net_osdep.h>
72
73 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
74 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
75
76 #define SIN6(s) ((struct sockaddr_in6 *)s)
77 #define SDL(s) ((struct sockaddr_dl *)s)
78
79 /*
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:
83 *
84 * RTF_GATEWAY is FALSE
85 * LLINFO is TRUE
86 * rt_gateway family is AF_LINK
87 * rt_llinfo is non-NULL
88 * The interfaces matches (or ifp is passed as NULL)
89 *
90 * NOTE: rt_llinfo can be NULL with LLINFO set, so both must be
91 * tested.
92 *
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.
97 */
98 #define ND6_IFP_MATCHES(ifp, ifa_ifp) \
99 ((ifp) == NULL || \
100 (ifa_ifp) == (ifp) || \
101 (((ifp)->if_flags & IFF_ISBRIDGE) && \
102 (ifa_ifp)->if_bridge == (ifp)->if_softc) \
103 )
104
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 && \
109 (rt)->rt_llinfo && \
110 ND6_IFP_MATCHES((ifp), (rt)->rt_ifa->ifa_ifp) \
111 )
112
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))
117
118 /* timer values */
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 */
125
126 /* preventing too many loops in ND option parsing */
127 int nd6_maxndopt = 10; /* max # of ND options allowed */
128
129 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */
130
131 #ifdef ND6_DEBUG
132 int nd6_debug = 1;
133 #else
134 int nd6_debug = 0;
135 #endif
136
137 /* for debugging? */
138 static int nd6_inuse, nd6_allocated;
139
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");
144
145 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL;
146 static struct sockaddr_in6 all1_sa;
147
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);
154
155 static struct callout nd6_slowtimo_ch;
156 static struct netmsg_base nd6_slowtimo_netmsg;
157
158 static struct callout nd6_timer_ch;
159 static struct netmsg_base nd6_timer_netmsg;
160
161 void
nd6_init(void)162 nd6_init(void)
163 {
164 static int nd6_init_done = 0;
165 int i;
166
167 if (nd6_init_done) {
168 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n");
169 return;
170 }
171
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;
176
177 /* initialization of the default router list */
178 TAILQ_INIT(&nd_defrouter);
179
180 nd6_init_done = 1;
181
182 /* start timer */
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);
188 }
189
190 struct nd_ifinfo *
nd6_ifattach(struct ifnet * ifp)191 nd6_ifattach(struct ifnet *ifp)
192 {
193 struct nd_ifinfo *nd;
194
195 nd = kmalloc(sizeof(*nd), M_IP6NDP, M_WAITOK | M_ZERO);
196
197 nd->initialized = 1;
198
199 nd->chlim = IPV6_DEFHLIM;
200 nd->basereachable = REACHABLE_TIME;
201 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable);
202 nd->retrans = RETRANS_TIMER;
203
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;
211
212 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
213 nd6_setmtu0(ifp, nd);
214
215 return nd;
216 }
217
218 void
nd6_ifdetach(struct nd_ifinfo * nd)219 nd6_ifdetach(struct nd_ifinfo *nd)
220 {
221 kfree(nd, M_IP6NDP);
222 }
223
224 /*
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.
227 */
228 void
nd6_setmtu(struct ifnet * ifp)229 nd6_setmtu(struct ifnet *ifp)
230 {
231 nd6_setmtu0(ifp, ND_IFINFO(ifp));
232 }
233
234 struct netmsg_nd6setmtu {
235 struct netmsg_base nmsg;
236 struct ifnet *ifp;
237 struct nd_ifinfo *ndi;
238 };
239
240 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
241 static void
nd6_setmtu0_dispatch(netmsg_t msg)242 nd6_setmtu0_dispatch(netmsg_t msg)
243 {
244 struct netmsg_nd6setmtu *nmsg = (struct netmsg_nd6setmtu *)msg;
245 struct ifnet *ifp = nmsg->ifp;
246 struct nd_ifinfo *ndi = nmsg->ndi;
247 uint32_t omaxmtu;
248
249 omaxmtu = ndi->maxmtu;
250
251 switch (ifp->if_type) {
252 case IFT_ETHER:
253 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
254 break;
255 case IFT_IEEE1394: /* XXX should be IEEE1394MTU(1500) */
256 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
257 break;
258 #ifdef IFT_IEEE80211
259 case IFT_IEEE80211: /* XXX should be IEEE80211MTU(1500) */
260 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
261 break;
262 #endif
263 default:
264 ndi->maxmtu = ifp->if_mtu;
265 break;
266 }
267
268 /*
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.
273 */
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);
278 }
279
280 if (ndi->maxmtu > in6_maxmtu)
281 in6_setmaxmtu(); /* check all interfaces just in case */
282
283 lwkt_replymsg(&nmsg->nmsg.lmsg, 0);
284 }
285
286 void
nd6_setmtu0(struct ifnet * ifp,struct nd_ifinfo * ndi)287 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi)
288 {
289 struct netmsg_nd6setmtu nmsg;
290
291 netmsg_init(&nmsg.nmsg, NULL, &curthread->td_msgport, 0,
292 nd6_setmtu0_dispatch);
293 nmsg.ifp = ifp;
294 nmsg.ndi = ndi;
295 lwkt_domsg(netisr_cpuport(0), &nmsg.nmsg.lmsg, 0);
296 }
297
298 void
nd6_option_init(void * opt,int icmp6len,union nd_opts * ndopts)299 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
300 {
301 bzero(ndopts, sizeof(*ndopts));
302 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
303 ndopts->nd_opts_last
304 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
305
306 if (icmp6len == 0) {
307 ndopts->nd_opts_done = 1;
308 ndopts->nd_opts_search = NULL;
309 }
310 }
311
312 /*
313 * Take one ND option.
314 */
315 struct nd_opt_hdr *
nd6_option(union nd_opts * ndopts)316 nd6_option(union nd_opts *ndopts)
317 {
318 struct nd_opt_hdr *nd_opt;
319 int olen;
320
321 if (!ndopts)
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)
326 return NULL;
327 if (ndopts->nd_opts_done)
328 return NULL;
329
330 nd_opt = ndopts->nd_opts_search;
331
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));
335 return NULL;
336 }
337
338 olen = nd_opt->nd_opt_len << 3;
339 if (olen == 0) {
340 /*
341 * Message validation requires that all included
342 * options have a length that is greater than zero.
343 */
344 bzero(ndopts, sizeof(*ndopts));
345 return NULL;
346 }
347
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));
352 return NULL;
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;
357 }
358 return nd_opt;
359 }
360
361 /*
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.
365 */
366 int
nd6_options(union nd_opts * ndopts)367 nd6_options(union nd_opts *ndopts)
368 {
369 struct nd_opt_hdr *nd_opt;
370 int i = 0;
371
372 if (!ndopts)
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)
377 return 0;
378
379 while (1) {
380 nd_opt = nd6_option(ndopts);
381 if (!nd_opt && !ndopts->nd_opts_last) {
382 /*
383 * Message validation requires that all included
384 * options have a length that is greater than zero.
385 */
386 icmp6stat.icp6s_nd_badopt++;
387 bzero(ndopts, sizeof(*ndopts));
388 return -1;
389 }
390
391 if (!nd_opt)
392 goto skip1;
393
394 switch (nd_opt->nd_opt_type) {
395 case ND_OPT_SOURCE_LINKADDR:
396 case ND_OPT_TARGET_LINKADDR:
397 case ND_OPT_MTU:
398 case ND_OPT_REDIRECTED_HEADER:
399 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
400 nd6log((LOG_INFO,
401 "duplicated ND6 option found (type=%d)\n",
402 nd_opt->nd_opt_type));
403 /* XXX bark? */
404 } else {
405 ndopts->nd_opt_array[nd_opt->nd_opt_type]
406 = nd_opt;
407 }
408 break;
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]
412 = nd_opt;
413 }
414 ndopts->nd_opts_pi_end =
415 (struct nd_opt_prefix_info *)nd_opt;
416 break;
417 default:
418 /*
419 * Unknown options must be silently ignored,
420 * to accomodate future extension to the protocol.
421 */
422 nd6log((LOG_DEBUG,
423 "nd6_options: unsupported option %d - "
424 "option ignored\n", nd_opt->nd_opt_type));
425 }
426
427 skip1:
428 i++;
429 if (i > nd6_maxndopt) {
430 icmp6stat.icp6s_nd_toomanyopt++;
431 nd6log((LOG_INFO, "too many loop in nd opt\n"));
432 break;
433 }
434
435 if (ndopts->nd_opts_done)
436 break;
437 }
438
439 return 0;
440 }
441
442 /*
443 * ND6 timer routine to expire default route list and prefix list
444 */
445 static void
nd6_timer_dispatch(netmsg_t nmsg)446 nd6_timer_dispatch(netmsg_t nmsg)
447 {
448 struct llinfo_nd6 *ln;
449 struct nd_defrouter *dr;
450 struct nd_prefix *pr;
451 struct ifnet *ifp;
452 struct in6_ifaddr *ia6, *nia6;
453
454 ASSERT_NETISR0;
455
456 crit_enter();
457 lwkt_replymsg(&nmsg->lmsg, 0); /* reply ASAP */
458 crit_exit();
459
460 mtx_lock(&nd6_mtx);
461
462 ln = llinfo_nd6.ln_next;
463 while (ln && ln != &llinfo_nd6) {
464 struct rtentry *rt;
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;
469
470 if ((rt = ln->ln_rt) == NULL) {
471 ln = next;
472 continue;
473 }
474 if ((ifp = rt->rt_ifp) == NULL) {
475 ln = next;
476 continue;
477 }
478 ndi = ND_IFINFO(ifp);
479 dst = (struct sockaddr_in6 *)rt_key(rt);
480
481 if (ln->ln_expire > time_uptime) {
482 ln = next;
483 continue;
484 }
485
486 /* sanity check */
487 if (!rt)
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)",
491 rt->rt_llinfo, ln);
492 if (!dst)
493 panic("dst=0 in nd6_timer(ln=%p)", ln);
494
495 switch (ln->ln_state) {
496 case ND6_LLINFO_WAITDELETE:
497 next = nd6_free(rt);
498 break;
499 case ND6_LLINFO_INCOMPLETE:
500 if (ln->ln_asked++ >= nd6_mmaxtries) {
501 struct mbuf *m = ln->ln_hold;
502 if (m) {
503 if (rt->rt_ifp) {
504 /*
505 * Fake rcvif to make ICMP error
506 * more helpful in diagnosing
507 * for the receiver.
508 * XXX: should we consider
509 * older rcvif?
510 */
511 m->m_pkthdr.rcvif = rt->rt_ifp;
512 }
513
514 /*
515 * mbuf has empty MAC header, remove
516 * for icmp. XXX layer violation.
517 */
518 m_adj(m, ETHER_HDR_LEN);
519 icmp6_error(m, ICMP6_DST_UNREACH,
520 ICMP6_DST_UNREACH_ADDR, 0);
521 ln->ln_hold = NULL;
522 }
523 ln->ln_state = ND6_LLINFO_WAITDELETE;
524 rt_rtmsg(RTM_MISS, rt, rt->rt_ifp, 0);
525 }
526 ln->ln_expire = time_uptime +
527 ND_IFINFO(ifp)->retrans / 1000;
528 nd6_ns_output(ifp, NULL, &dst->sin6_addr,
529 ln, 0);
530 break;
531 case ND6_LLINFO_REACHABLE:
532 if (ln->ln_expire) {
533 ln->ln_state = ND6_LLINFO_STALE;
534 ln->ln_expire = time_uptime + nd6_gctimer;
535 }
536 break;
537
538 case ND6_LLINFO_STALE:
539 /* Garbage Collection(RFC 2461 5.3) */
540 if (ln->ln_expire)
541 next = nd6_free(rt);
542 break;
543
544 case ND6_LLINFO_DELAY:
545 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD)) {
546 /* We need NUD */
547 ln->ln_asked = 1;
548 ln->ln_state = ND6_LLINFO_PROBE;
549 ln->ln_expire = time_uptime +
550 ndi->retrans / 1000;
551 nd6_ns_output(ifp, &dst->sin6_addr,
552 &dst->sin6_addr,
553 ln, 0);
554 } else {
555 ln->ln_state = ND6_LLINFO_STALE; /* XXX */
556 ln->ln_expire = time_uptime + nd6_gctimer;
557 }
558 break;
559 case ND6_LLINFO_PROBE:
560 if (ln->ln_asked < nd6_umaxtries) {
561 ln->ln_asked++;
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);
566 } else {
567 rt_rtmsg(RTM_MISS, rt, rt->rt_ifp, 0);
568 next = nd6_free(rt);
569 }
570 break;
571 }
572 ln = next;
573 }
574
575 /* expire default router list */
576 dr = TAILQ_FIRST(&nd_defrouter);
577 while (dr) {
578 if (dr->expire && dr->expire < time_uptime) {
579 struct nd_defrouter *t;
580 t = TAILQ_NEXT(dr, dr_entry);
581 defrtrlist_del(dr);
582 dr = t;
583 } else {
584 dr = TAILQ_NEXT(dr, dr_entry);
585 }
586 }
587
588 /*
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.
593 */
594 addrloop:
595 for (ia6 = in6_ifaddr; ia6; ia6 = nia6) {
596 nia6 = ia6->ia_next;
597 /* check address lifetime */
598 if (IFA6_IS_INVALID(ia6)) {
599 int regen = 0;
600
601 /*
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
609 * regeneration.
610 */
611 if (ip6_use_tempaddr &&
612 (ia6->ia6_flags & IN6_IFF_TEMPORARY)) {
613 if (regen_tmpaddr(ia6) == 0)
614 regen = 1;
615 }
616
617 in6_purgeaddr(&ia6->ia_ifa);
618
619 if (regen)
620 goto addrloop; /* XXX: see below */
621 /* ia6 is no longer good, continue on to next */
622 continue;
623 }
624 if (IFA6_IS_DEPRECATED(ia6)) {
625 int oldflags = ia6->ia6_flags;
626
627 if ((oldflags & IN6_IFF_DEPRECATED) == 0) {
628 ia6->ia6_flags |= IN6_IFF_DEPRECATED;
629 in6_newaddrmsg((struct ifaddr *)ia6);
630 }
631
632 /*
633 * If a temporary address has just become deprecated,
634 * regenerate a new one if possible.
635 */
636 if (ip6_use_tempaddr &&
637 (ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
638 !(oldflags & IN6_IFF_DEPRECATED)) {
639
640 if (regen_tmpaddr(ia6) == 0) {
641 /*
642 * A new temporary address is
643 * generated.
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??
652 */
653 goto addrloop;
654 }
655 }
656 } else {
657 /*
658 * A new RA might have made a deprecated address
659 * preferred.
660 */
661 if (ia6->ia6_flags & IN6_IFF_DEPRECATED) {
662 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
663 in6_newaddrmsg((struct ifaddr *)ia6);
664 }
665 }
666 }
667
668 /* expire prefix list */
669 pr = nd_prefix.lh_first;
670 while (pr) {
671 /*
672 * check prefix lifetime.
673 * since pltime is just for autoconf, pltime processing for
674 * prefix is not necessary.
675 */
676 if (pr->ndpr_expire && pr->ndpr_expire < time_uptime) {
677 struct nd_prefix *t;
678 t = pr->ndpr_next;
679
680 /*
681 * address expiration and prefix expiration are
682 * separate. NEVER perform in6_purgeaddr here.
683 */
684
685 prelist_remove(pr);
686 pr = t;
687 } else
688 pr = pr->ndpr_next;
689 }
690
691 mtx_unlock(&nd6_mtx);
692
693 callout_reset(&nd6_timer_ch, nd6_prune * hz, nd6_timer, NULL);
694 }
695
696 static void
nd6_timer(void * arg __unused)697 nd6_timer(void *arg __unused)
698 {
699 struct lwkt_msg *lmsg = &nd6_timer_netmsg.lmsg;
700
701 KASSERT(mycpuid == 0, ("not on cpu0"));
702 crit_enter();
703 if (lmsg->ms_flags & MSGF_DONE)
704 lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg);
705 crit_exit();
706 }
707
708 void
nd6_timer_init(void)709 nd6_timer_init(void)
710 {
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);
715 }
716
717 static int
regen_tmpaddr(struct in6_ifaddr * ia6)718 regen_tmpaddr(struct in6_ifaddr *ia6) /* deprecated/invalidated temporary
719 address */
720 {
721 struct ifaddr_container *ifac;
722 struct ifnet *ifp;
723 struct in6_ifaddr *public_ifa6 = NULL;
724
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;
729
730 if (ifa->ifa_addr->sa_family != AF_INET6)
731 continue;
732
733 it6 = (struct in6_ifaddr *)ifa;
734
735 /* ignore no autoconf addresses. */
736 if (!(it6->ia6_flags & IN6_IFF_AUTOCONF))
737 continue;
738
739 /* ignore autoconf addresses with different prefixes. */
740 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
741 continue;
742
743 /*
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
748 * a long period.
749 */
750 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) &&
751 !IFA6_IS_DEPRECATED(it6)) {
752 public_ifa6 = NULL;
753 break;
754 }
755
756 /*
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.
761 */
762 if (!IFA6_IS_DEPRECATED(it6))
763 public_ifa6 = it6;
764 }
765
766 if (public_ifa6 != NULL) {
767 int e;
768
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);
772 return (-1);
773 }
774 return (0);
775 }
776
777 return (-1);
778 }
779
780 /*
781 * Nuke neighbor cache/prefix/default router management table, right before
782 * ifp goes away.
783 */
784 void
nd6_purge(struct ifnet * ifp)785 nd6_purge(struct ifnet *ifp)
786 {
787 struct llinfo_nd6 *ln, *nln;
788 struct nd_defrouter *dr, *ndr, drany;
789 struct nd_prefix *pr, *npr;
790
791 /* Nuke default router list entries toward ifp */
792 if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
793 /*
794 * The first entry of the list may be stored in
795 * the routing table, so we'll delete it later.
796 */
797 for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = ndr) {
798 ndr = TAILQ_NEXT(dr, dr_entry);
799 if (dr->ifp == ifp)
800 defrtrlist_del(dr);
801 }
802 dr = TAILQ_FIRST(&nd_defrouter);
803 if (dr->ifp == ifp)
804 defrtrlist_del(dr);
805 }
806
807 /* Nuke prefix list entries toward ifp */
808 for (pr = nd_prefix.lh_first; pr; pr = npr) {
809 npr = pr->ndpr_next;
810 if (pr->ndpr_ifp == ifp) {
811 /*
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
816 * by itself.
817 * (jinmei@kame.net 20010129)
818 */
819 prelist_remove(pr);
820 }
821 }
822
823 /* cancel default outgoing interface setting */
824 if (nd6_defifindex == ifp->if_index)
825 nd6_setdefaultiface(0);
826
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);
832 defrouter_select();
833 }
834
835 /*
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().
840 */
841 ln = llinfo_nd6.ln_next;
842 while (ln && ln != &llinfo_nd6) {
843 struct rtentry *rt;
844 struct sockaddr_dl *sdl;
845
846 nln = ln->ln_next;
847 rt = ln->ln_rt;
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)
852 nln = nd6_free(rt);
853 }
854 ln = nln;
855 }
856 }
857
858 struct rtentry *
nd6_lookup(struct in6_addr * addr6,int create,struct ifnet * ifp)859 nd6_lookup(struct in6_addr *addr6, int create, struct ifnet *ifp)
860 {
861 struct rtentry *rt;
862 struct sockaddr_in6 sin6;
863
864 bzero(&sin6, sizeof(sin6));
865 sin6.sin6_len = sizeof(struct sockaddr_in6);
866 sin6.sin6_family = AF_INET6;
867 sin6.sin6_addr = *addr6;
868
869 if (create)
870 rt = rtlookup((struct sockaddr *)&sin6);
871 else
872 rt = rtpurelookup((struct sockaddr *)&sin6);
873 if (rt && !(rt->rt_flags & RTF_LLINFO)) {
874 /*
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
878 * interface route.
879 */
880 if (create) {
881 --rt->rt_refcnt;
882 rt = NULL;
883 }
884 }
885 if (!rt) {
886 if (create && ifp) {
887 int e;
888
889 /*
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.
895 */
896 struct ifaddr *ifa;
897
898 ifa = ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp);
899 if (ifa == NULL)
900 return (NULL);
901
902 /*
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.
907 */
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) {
912 log(LOG_ERR,
913 "nd6_lookup: failed to add route for a "
914 "neighbor(%s), errno=%d\n",
915 ip6_sprintf(addr6), e);
916 }
917 if (rt == NULL)
918 return (NULL);
919 if (rt->rt_llinfo) {
920 struct llinfo_nd6 *ln =
921 (struct llinfo_nd6 *)rt->rt_llinfo;
922
923 ln->ln_state = ND6_LLINFO_NOSTATE;
924 }
925 } else
926 return (NULL);
927 }
928 rt->rt_refcnt--;
929
930 if (!ND6_RTENTRY_IS_NEIGHBOR(rt, ifp)) {
931 if (create) {
932 log(LOG_DEBUG,
933 "nd6_lookup: failed to lookup %s (if = %s)\n",
934 ip6_sprintf(addr6), ifp ? if_name(ifp) : "unspec");
935 /* xxx more logs... kazu */
936 }
937 return (NULL);
938 }
939 return (rt);
940 }
941
942 static struct rtentry *
nd6_neighbor_lookup(struct in6_addr * addr6,struct ifnet * ifp)943 nd6_neighbor_lookup(struct in6_addr *addr6, struct ifnet *ifp)
944 {
945 struct rtentry *rt;
946 struct sockaddr_in6 sin6;
947
948 bzero(&sin6, sizeof(sin6));
949 sin6.sin6_len = sizeof(struct sockaddr_in6);
950 sin6.sin6_family = AF_INET6;
951 sin6.sin6_addr = *addr6;
952
953 rt = rtpurelookup((struct sockaddr *)&sin6);
954 if (rt == NULL)
955 return (NULL);
956 rt->rt_refcnt--;
957
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)))) {
963 /*
964 * If cloning ever happened or is happening,
965 * rtentry for addr6 would or will become a
966 * neighbor cache.
967 */
968 } else {
969 rt = NULL;
970 }
971 }
972 return (rt);
973 }
974
975 /*
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?
978 */
979 int
nd6_is_addr_neighbor(struct sockaddr_in6 * addr,struct ifnet * ifp)980 nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
981 {
982 struct ifaddr_container *ifac;
983
984 #define IFADDR6(a) ((((struct in6_ifaddr *)(a))->ia_addr).sin6_addr)
985 #define IFMASK6(a) ((((struct in6_ifaddr *)(a))->ia_prefixmask).sin6_addr)
986
987 /*
988 * A link-local address is always a neighbor.
989 * XXX: we should use the sin6_scope_id field rather than the embedded
990 * interface index.
991 */
992 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr) &&
993 ntohs(*(u_int16_t *)&addr->sin6_addr.s6_addr[2]) == ifp->if_index)
994 return (1);
995
996 /*
997 * If the address matches one of our addresses,
998 * it should be a neighbor.
999 */
1000 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
1001 struct ifaddr *ifa = ifac->ifa;
1002
1003 if (ifa->ifa_addr->sa_family != AF_INET6)
1004 continue;
1005
1006 if (IN6_ARE_MASKED_ADDR_EQUAL(&IFADDR6(ifa), &addr->sin6_addr,
1007 &IFMASK6(ifa)))
1008 return (1);
1009 }
1010
1011 /*
1012 * Even if the address matches none of our addresses, it might be
1013 * in the neighbor cache.
1014 */
1015 if (nd6_neighbor_lookup(&addr->sin6_addr, ifp) != NULL)
1016 return (1);
1017
1018 return (0);
1019 #undef IFADDR6
1020 #undef IFMASK6
1021 }
1022
1023 /*
1024 * Free an nd6 llinfo entry.
1025 */
1026 struct llinfo_nd6 *
nd6_free(struct rtentry * rt)1027 nd6_free(struct rtentry *rt)
1028 {
1029 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next;
1030 struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
1031 struct nd_defrouter *dr;
1032
1033 /*
1034 * we used to have kpfctlinput(PRC_HOSTDEAD) here.
1035 * even though it is not harmful, it was not really necessary.
1036 */
1037
1038 /* XXX: this condition too restrictive? */
1039 if (!ip6_forwarding &&
1040 (ND_IFINFO(rt->rt_ifp)->flags & ND6_IFF_ACCEPT_RTADV)) {
1041 mtx_lock(&nd6_mtx);
1042 dr = defrouter_lookup(
1043 &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
1044 rt->rt_ifp);
1045
1046 if (ln->ln_router || dr) {
1047 /*
1048 * rt6_flush must be called whether or not the neighbor
1049 * is in the Default Router List.
1050 * See a corresponding comment in nd6_na_input().
1051 */
1052 rt6_flush(&in6, rt->rt_ifp);
1053 }
1054
1055 if (dr) {
1056 /*
1057 * Unreachablity of a router might affect the default
1058 * router selection and on-link detection of advertised
1059 * prefixes.
1060 */
1061
1062 /*
1063 * Temporarily fake the state to choose a new default
1064 * router and to perform on-link determination of
1065 * prefixes correctly.
1066 * Below the state will be set correctly,
1067 * or the entry itself will be deleted.
1068 */
1069 ln->ln_state = ND6_LLINFO_INCOMPLETE;
1070
1071 /*
1072 * Since defrouter_select() does not affect the
1073 * on-link determination and MIP6 needs the check
1074 * before the default router selection, we perform
1075 * the check now.
1076 */
1077 pfxlist_onlink_check();
1078
1079 if (dr == TAILQ_FIRST(&nd_defrouter)) {
1080 /*
1081 * It is used as the current default router,
1082 * so we have to move it to the end of the
1083 * list and choose a new one.
1084 * XXX: it is not very efficient if this is
1085 * the only router.
1086 */
1087 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
1088 TAILQ_INSERT_TAIL(&nd_defrouter, dr, dr_entry);
1089
1090 defrouter_select();
1091 }
1092 }
1093 mtx_unlock(&nd6_mtx);
1094 }
1095
1096 /*
1097 * Before deleting the entry, remember the next entry as the
1098 * return value. We need this because pfxlist_onlink_check() above
1099 * might have freed other entries (particularly the old next entry) as
1100 * a side effect (XXX).
1101 */
1102 next = ln->ln_next;
1103
1104 /*
1105 * Detach the route from the routing tree and the list of neighbor
1106 * caches, and disable the route entry not to be used in already
1107 * cached routes.
1108 *
1109 * ND expiry happens under one big timer.
1110 * To avoid overflowing the route socket, don't report this.
1111 * Now that RTM_MISS is reported when an address is unresolvable
1112 * the benefit of reporting this deletion is questionable.
1113 */
1114 rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
1115
1116 return (next);
1117 }
1118
1119 /*
1120 * Upper-layer reachability hint for Neighbor Unreachability Detection.
1121 *
1122 * XXX cost-effective metods?
1123 */
1124 void
nd6_nud_hint(struct rtentry * rt,struct in6_addr * dst6,int force)1125 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force)
1126 {
1127 struct llinfo_nd6 *ln;
1128
1129 /*
1130 * If the caller specified "rt", use that. Otherwise, resolve the
1131 * routing table by supplied "dst6".
1132 */
1133 if (!rt) {
1134 if (!dst6)
1135 return;
1136 if (!(rt = nd6_lookup(dst6, 0, NULL)))
1137 return;
1138 }
1139
1140 if ((rt->rt_flags & RTF_GATEWAY) ||
1141 !(rt->rt_flags & RTF_LLINFO) ||
1142 rt->rt_llinfo == NULL || rt->rt_gateway == NULL ||
1143 rt->rt_gateway->sa_family != AF_LINK) {
1144 /* This is not a host route. */
1145 return;
1146 }
1147
1148 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1149 if (ln->ln_state < ND6_LLINFO_REACHABLE)
1150 return;
1151
1152 /*
1153 * if we get upper-layer reachability confirmation many times,
1154 * it is possible we have false information.
1155 */
1156 if (!force) {
1157 ln->ln_byhint++;
1158 if (ln->ln_byhint > nd6_maxnudhint)
1159 return;
1160 }
1161
1162 ln->ln_state = ND6_LLINFO_REACHABLE;
1163 if (ln->ln_expire)
1164 ln->ln_expire = time_uptime +
1165 ND_IFINFO(rt->rt_ifp)->reachable;
1166 }
1167
1168 void
nd6_rtrequest(int req,struct rtentry * rt)1169 nd6_rtrequest(int req, struct rtentry *rt)
1170 {
1171 struct sockaddr *gate = rt->rt_gateway;
1172 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1173 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
1174 struct ifnet *ifp = rt->rt_ifp;
1175 struct ifaddr *ifa;
1176
1177 if ((rt->rt_flags & RTF_GATEWAY))
1178 return;
1179
1180 if (nd6_need_cache(ifp) == 0 && !(rt->rt_flags & RTF_HOST)) {
1181 /*
1182 * This is probably an interface direct route for a link
1183 * which does not need neighbor caches (e.g. fe80::%lo0/64).
1184 * We do not need special treatment below for such a route.
1185 * Moreover, the RTF_LLINFO flag which would be set below
1186 * would annoy the ndp(8) command.
1187 */
1188 return;
1189 }
1190
1191 if (req == RTM_RESOLVE &&
1192 (nd6_need_cache(ifp) == 0 || /* stf case */
1193 !nd6_is_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), ifp))) {
1194 /*
1195 * FreeBSD and BSD/OS often make a cloned host route based
1196 * on a less-specific route (e.g. the default route).
1197 * If the less specific route does not have a "gateway"
1198 * (this is the case when the route just goes to a p2p or an
1199 * stf interface), we'll mistakenly make a neighbor cache for
1200 * the host route, and will see strange neighbor solicitation
1201 * for the corresponding destination. In order to avoid the
1202 * confusion, we check if the destination of the route is
1203 * a neighbor in terms of neighbor discovery, and stop the
1204 * process if not. Additionally, we remove the LLINFO flag
1205 * so that ndp(8) will not try to get the neighbor information
1206 * of the destination.
1207 */
1208 rt->rt_flags &= ~RTF_LLINFO;
1209 return;
1210 }
1211
1212 switch (req) {
1213 case RTM_ADD:
1214 /*
1215 * There is no backward compatibility :)
1216 *
1217 * if (!(rt->rt_flags & RTF_HOST) &&
1218 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
1219 * rt->rt_flags |= RTF_CLONING;
1220 */
1221 if (rt->rt_flags & (RTF_CLONING | RTF_LLINFO)) {
1222 /*
1223 * Case 1: This route should come from
1224 * a route to interface. RTF_LLINFO flag is set
1225 * for a host route whose destination should be
1226 * treated as on-link.
1227 */
1228 rt_setgate(rt, rt_key(rt),
1229 (struct sockaddr *)&null_sdl);
1230 gate = rt->rt_gateway;
1231 SDL(gate)->sdl_type = ifp->if_type;
1232 SDL(gate)->sdl_index = ifp->if_index;
1233 if (ln)
1234 ln->ln_expire = time_uptime;
1235 if (ln && ln->ln_expire == 0) {
1236 /* kludge for desktops */
1237 ln->ln_expire = 1;
1238 }
1239 if ((rt->rt_flags & RTF_CLONING))
1240 break;
1241 }
1242 /*
1243 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here.
1244 * We don't do that here since llinfo is not ready yet.
1245 *
1246 * There are also couple of other things to be discussed:
1247 * - unsolicited NA code needs improvement beforehand
1248 * - RFC2461 says we MAY send multicast unsolicited NA
1249 * (7.2.6 paragraph 4), however, it also says that we
1250 * SHOULD provide a mechanism to prevent multicast NA storm.
1251 * we don't have anything like it right now.
1252 * note that the mechanism needs a mutual agreement
1253 * between proxies, which means that we need to implement
1254 * a new protocol, or a new kludge.
1255 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA.
1256 * we need to check ip6forwarding before sending it.
1257 * (or should we allow proxy ND configuration only for
1258 * routers? there's no mention about proxy ND from hosts)
1259 */
1260 #if 0
1261 /* XXX it does not work */
1262 if ((rt->rt_flags & RTF_ANNOUNCE) && mycpuid == 0) {
1263 nd6_na_output(ifp,
1264 &SIN6(rt_key(rt))->sin6_addr,
1265 &SIN6(rt_key(rt))->sin6_addr,
1266 ip6_forwarding ? ND_NA_FLAG_ROUTER : 0,
1267 1, NULL);
1268 }
1269 #endif
1270 /* FALLTHROUGH */
1271 case RTM_RESOLVE:
1272 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) {
1273 /*
1274 * Address resolution isn't necessary for a point to
1275 * point link, so we can skip this test for a p2p link.
1276 */
1277 if (gate->sa_family != AF_LINK ||
1278 gate->sa_len < sizeof(null_sdl)) {
1279 log(LOG_DEBUG,
1280 "nd6_rtrequest: bad gateway value: %s\n",
1281 if_name(ifp));
1282 break;
1283 }
1284 SDL(gate)->sdl_type = ifp->if_type;
1285 SDL(gate)->sdl_index = ifp->if_index;
1286 }
1287 if (ln != NULL)
1288 break; /* This happens on a route change */
1289 /*
1290 * Case 2: This route may come from cloning, or a manual route
1291 * add with a LL address.
1292 */
1293 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln));
1294 rt->rt_llinfo = (caddr_t)ln;
1295 if (!ln) {
1296 log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n");
1297 break;
1298 }
1299 nd6_inuse++;
1300 nd6_allocated++;
1301 bzero(ln, sizeof(*ln));
1302 ln->ln_rt = rt;
1303 /* this is required for "ndp" command. - shin */
1304 if (req == RTM_ADD) {
1305 /*
1306 * gate should have some valid AF_LINK entry,
1307 * and ln->ln_expire should have some lifetime
1308 * which is specified by ndp command.
1309 */
1310 ln->ln_state = ND6_LLINFO_REACHABLE;
1311 ln->ln_byhint = 0;
1312 } else {
1313 /*
1314 * When req == RTM_RESOLVE, rt is created and
1315 * initialized in rtrequest(), so rt_expire is 0.
1316 */
1317 ln->ln_state = ND6_LLINFO_NOSTATE;
1318 ln->ln_expire = time_uptime;
1319 }
1320 rt->rt_flags |= RTF_LLINFO;
1321 ln->ln_next = llinfo_nd6.ln_next;
1322 llinfo_nd6.ln_next = ln;
1323 ln->ln_prev = &llinfo_nd6;
1324 ln->ln_next->ln_prev = ln;
1325
1326 /*
1327 * check if rt_key(rt) is one of my address assigned
1328 * to the interface.
1329 */
1330 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp,
1331 &SIN6(rt_key(rt))->sin6_addr);
1332 if (ifa) {
1333 caddr_t macp = nd6_ifptomac(ifp);
1334 ln->ln_expire = 0;
1335 ln->ln_state = ND6_LLINFO_REACHABLE;
1336 ln->ln_byhint = 0;
1337 if (macp) {
1338 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen);
1339 SDL(gate)->sdl_alen = ifp->if_addrlen;
1340 }
1341 if (nd6_useloopback) {
1342 rt->rt_ifp = loif; /* XXX */
1343 /*
1344 * Make sure rt_ifa be equal to the ifaddr
1345 * corresponding to the address.
1346 * We need this because when we refer
1347 * rt_ifa->ia6_flags in ip6_input, we assume
1348 * that the rt_ifa points to the address instead
1349 * of the loopback address.
1350 */
1351 if (ifa != rt->rt_ifa) {
1352 IFAFREE(rt->rt_ifa);
1353 IFAREF(ifa);
1354 rt->rt_ifa = ifa;
1355 }
1356 }
1357 } else if (rt->rt_flags & RTF_ANNOUNCE) {
1358 ln->ln_expire = 0;
1359 ln->ln_state = ND6_LLINFO_REACHABLE;
1360 ln->ln_byhint = 0;
1361
1362 /*
1363 * Join solicited node multicast for proxy ND, and only
1364 * join it once on cpu0.
1365 */
1366 if ((ifp->if_flags & IFF_MULTICAST) && mycpuid == 0) {
1367 struct in6_addr llsol;
1368 int error;
1369
1370 llsol = SIN6(rt_key(rt))->sin6_addr;
1371 llsol.s6_addr16[0] = htons(0xff02);
1372 llsol.s6_addr16[1] = htons(ifp->if_index);
1373 llsol.s6_addr32[1] = 0;
1374 llsol.s6_addr32[2] = htonl(1);
1375 llsol.s6_addr8[12] = 0xff;
1376
1377 if (!in6_addmulti(&llsol, ifp, &error)) {
1378 nd6log((LOG_ERR, "%s: failed to join "
1379 "%s (errno=%d)\n", if_name(ifp),
1380 ip6_sprintf(&llsol), error));
1381 }
1382 }
1383 }
1384 break;
1385
1386 case RTM_DELETE:
1387 if (!ln)
1388 break;
1389 /*
1390 * Leave from solicited node multicast for proxy ND, and only
1391 * leave it once on cpu0 (since we joined it once on cpu0).
1392 */
1393 if ((rt->rt_flags & RTF_ANNOUNCE) &&
1394 (ifp->if_flags & IFF_MULTICAST) && mycpuid == 0) {
1395 struct in6_addr llsol;
1396 struct in6_multi *in6m;
1397
1398 llsol = SIN6(rt_key(rt))->sin6_addr;
1399 llsol.s6_addr16[0] = htons(0xff02);
1400 llsol.s6_addr16[1] = htons(ifp->if_index);
1401 llsol.s6_addr32[1] = 0;
1402 llsol.s6_addr32[2] = htonl(1);
1403 llsol.s6_addr8[12] = 0xff;
1404
1405 in6m = IN6_LOOKUP_MULTI(&llsol, ifp);
1406 if (in6m)
1407 in6_delmulti(in6m);
1408 }
1409 nd6_inuse--;
1410 ln->ln_next->ln_prev = ln->ln_prev;
1411 ln->ln_prev->ln_next = ln->ln_next;
1412 ln->ln_prev = NULL;
1413 rt->rt_llinfo = 0;
1414 rt->rt_flags &= ~RTF_LLINFO;
1415 if (ln->ln_hold)
1416 m_freem(ln->ln_hold);
1417 R_Free(ln);
1418 }
1419 }
1420
1421 int
nd6_ioctl(u_long cmd,caddr_t data,struct ifnet * ifp)1422 nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
1423 {
1424 struct in6_drlist *drl = (struct in6_drlist *)data;
1425 struct in6_prlist *prl = (struct in6_prlist *)data;
1426 struct in6_ndireq *ndi = (struct in6_ndireq *)data;
1427 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
1428 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
1429 struct nd_defrouter *dr, any;
1430 struct nd_prefix *pr;
1431 struct rtentry *rt;
1432 int i = 0, error = 0;
1433
1434 switch (cmd) {
1435 case SIOCGDRLST_IN6:
1436 /*
1437 * obsolete API, use sysctl under net.inet6.icmp6
1438 */
1439 bzero(drl, sizeof(*drl));
1440 mtx_lock(&nd6_mtx);
1441 dr = TAILQ_FIRST(&nd_defrouter);
1442 while (dr && i < DRLSTSIZ) {
1443 drl->defrouter[i].rtaddr = dr->rtaddr;
1444 if (IN6_IS_ADDR_LINKLOCAL(&drl->defrouter[i].rtaddr)) {
1445 /* XXX: need to this hack for KAME stack */
1446 drl->defrouter[i].rtaddr.s6_addr16[1] = 0;
1447 } else
1448 log(LOG_ERR,
1449 "default router list contains a "
1450 "non-linklocal address(%s)\n",
1451 ip6_sprintf(&drl->defrouter[i].rtaddr));
1452
1453 drl->defrouter[i].flags = dr->flags;
1454 drl->defrouter[i].rtlifetime = dr->rtlifetime;
1455 drl->defrouter[i].expire = dr->expire;
1456 drl->defrouter[i].if_index = dr->ifp->if_index;
1457 i++;
1458 dr = TAILQ_NEXT(dr, dr_entry);
1459 }
1460 mtx_unlock(&nd6_mtx);
1461 break;
1462 case SIOCGPRLST_IN6:
1463 /*
1464 * obsolete API, use sysctl under net.inet6.icmp6
1465 */
1466 /*
1467 * XXX meaning of fields, especialy "raflags", is very
1468 * differnet between RA prefix list and RR/static prefix list.
1469 * how about separating ioctls into two?
1470 */
1471 bzero(prl, sizeof(*prl));
1472 mtx_lock(&nd6_mtx);
1473 pr = nd_prefix.lh_first;
1474 while (pr && i < PRLSTSIZ) {
1475 struct nd_pfxrouter *pfr;
1476 int j;
1477
1478 in6_embedscope(&prl->prefix[i].prefix,
1479 &pr->ndpr_prefix, NULL, NULL);
1480 prl->prefix[i].raflags = pr->ndpr_raf;
1481 prl->prefix[i].prefixlen = pr->ndpr_plen;
1482 prl->prefix[i].vltime = pr->ndpr_vltime;
1483 prl->prefix[i].pltime = pr->ndpr_pltime;
1484 prl->prefix[i].if_index = pr->ndpr_ifp->if_index;
1485 prl->prefix[i].expire = pr->ndpr_expire;
1486
1487 pfr = pr->ndpr_advrtrs.lh_first;
1488 j = 0;
1489 while (pfr) {
1490 if (j < DRLSTSIZ) {
1491 #define RTRADDR prl->prefix[i].advrtr[j]
1492 RTRADDR = pfr->router->rtaddr;
1493 if (IN6_IS_ADDR_LINKLOCAL(&RTRADDR)) {
1494 /* XXX: hack for KAME */
1495 RTRADDR.s6_addr16[1] = 0;
1496 } else
1497 log(LOG_ERR,
1498 "a router(%s) advertises "
1499 "a prefix with "
1500 "non-link local address\n",
1501 ip6_sprintf(&RTRADDR));
1502 #undef RTRADDR
1503 }
1504 j++;
1505 pfr = pfr->pfr_next;
1506 }
1507 prl->prefix[i].advrtrs = j;
1508 prl->prefix[i].origin = PR_ORIG_RA;
1509
1510 i++;
1511 pr = pr->ndpr_next;
1512 }
1513 mtx_unlock(&nd6_mtx);
1514
1515 break;
1516 case OSIOCGIFINFO_IN6:
1517 /* XXX: old ndp(8) assumes a positive value for linkmtu. */
1518 bzero(&ndi->ndi, sizeof(ndi->ndi));
1519 ndi->ndi.linkmtu = IN6_LINKMTU(ifp);
1520 ndi->ndi.maxmtu = ND_IFINFO(ifp)->maxmtu;
1521 ndi->ndi.basereachable = ND_IFINFO(ifp)->basereachable;
1522 ndi->ndi.reachable = ND_IFINFO(ifp)->reachable;
1523 ndi->ndi.retrans = ND_IFINFO(ifp)->retrans;
1524 ndi->ndi.flags = ND_IFINFO(ifp)->flags;
1525 ndi->ndi.recalctm = ND_IFINFO(ifp)->recalctm;
1526 ndi->ndi.chlim = ND_IFINFO(ifp)->chlim;
1527 break;
1528 case SIOCGIFINFO_IN6:
1529 ndi->ndi = *ND_IFINFO(ifp);
1530 ndi->ndi.linkmtu = IN6_LINKMTU(ifp);
1531 break;
1532 case SIOCSIFINFO_IN6:
1533 /*
1534 * used to change host variables from userland.
1535 * intented for a use on router to reflect RA configurations.
1536 */
1537 /* 0 means 'unspecified' */
1538 if (ndi->ndi.linkmtu != 0) {
1539 if (ndi->ndi.linkmtu < IPV6_MMTU ||
1540 ndi->ndi.linkmtu > IN6_LINKMTU(ifp)) {
1541 error = EINVAL;
1542 break;
1543 }
1544 ND_IFINFO(ifp)->linkmtu = ndi->ndi.linkmtu;
1545 }
1546
1547 if (ndi->ndi.basereachable != 0) {
1548 int obasereachable = ND_IFINFO(ifp)->basereachable;
1549
1550 ND_IFINFO(ifp)->basereachable = ndi->ndi.basereachable;
1551 if (ndi->ndi.basereachable != obasereachable)
1552 ND_IFINFO(ifp)->reachable =
1553 ND_COMPUTE_RTIME(ndi->ndi.basereachable);
1554 }
1555 if (ndi->ndi.retrans != 0)
1556 ND_IFINFO(ifp)->retrans = ndi->ndi.retrans;
1557 if (ndi->ndi.chlim != 0)
1558 ND_IFINFO(ifp)->chlim = ndi->ndi.chlim;
1559 /* FALLTHROUGH */
1560 case SIOCSIFINFO_FLAGS:
1561 if ((ndi->ndi.flags & ND6_IFF_AUTO_LINKLOCAL) &&
1562 !(ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL)) {
1563 /* auto_linklocal 0->1 transision */
1564 ND_IFINFO(ifp)->flags |= ND6_IFF_AUTO_LINKLOCAL;
1565 in6_ifattach(ifp, NULL);
1566 }
1567 ND_IFINFO(ifp)->flags = ndi->ndi.flags;
1568 break;
1569 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */
1570 /* flush default router list */
1571 /*
1572 * xxx sumikawa: should not delete route if default
1573 * route equals to the top of default router list
1574 */
1575 bzero(&any, sizeof(any));
1576 defrouter_delreq(&any, 0);
1577 defrouter_select();
1578 /* xxx sumikawa: flush prefix list */
1579 break;
1580 case SIOCSPFXFLUSH_IN6:
1581 {
1582 /* flush all the prefix advertised by routers */
1583 struct nd_prefix *pr, *next;
1584
1585 mtx_lock(&nd6_mtx);
1586 for (pr = nd_prefix.lh_first; pr; pr = next) {
1587 struct in6_ifaddr *ia, *ia_next;
1588
1589 next = pr->ndpr_next;
1590
1591 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1592 continue; /* XXX */
1593
1594 /* do we really have to remove addresses as well? */
1595 for (ia = in6_ifaddr; ia; ia = ia_next) {
1596 /* ia might be removed. keep the next ptr. */
1597 ia_next = ia->ia_next;
1598
1599 if (!(ia->ia6_flags & IN6_IFF_AUTOCONF))
1600 continue;
1601
1602 if (ia->ia6_ndpr == pr)
1603 in6_purgeaddr(&ia->ia_ifa);
1604 }
1605 prelist_remove(pr);
1606 }
1607 mtx_unlock(&nd6_mtx);
1608 break;
1609 }
1610 case SIOCSRTRFLUSH_IN6:
1611 {
1612 /* flush all the default routers */
1613 struct nd_defrouter *dr, *next;
1614
1615 mtx_lock(&nd6_mtx);
1616 if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
1617 /*
1618 * The first entry of the list may be stored in
1619 * the routing table, so we'll delete it later.
1620 */
1621 for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = next) {
1622 next = TAILQ_NEXT(dr, dr_entry);
1623 defrtrlist_del(dr);
1624 }
1625 defrtrlist_del(TAILQ_FIRST(&nd_defrouter));
1626 }
1627 mtx_unlock(&nd6_mtx);
1628 break;
1629 }
1630 case SIOCGNBRINFO_IN6:
1631 {
1632 struct llinfo_nd6 *ln;
1633 struct in6_addr nb_addr = nbi->addr; /* make local for safety */
1634
1635 /*
1636 * XXX: KAME specific hack for scoped addresses
1637 * XXXX: for other scopes than link-local?
1638 */
1639 if (IN6_IS_ADDR_LINKLOCAL(&nbi->addr) ||
1640 IN6_IS_ADDR_MC_LINKLOCAL(&nbi->addr)) {
1641 u_int16_t *idp = (u_int16_t *)&nb_addr.s6_addr[2];
1642
1643 if (*idp == 0)
1644 *idp = htons(ifp->if_index);
1645 }
1646
1647 mtx_lock(&nd6_mtx);
1648 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL) {
1649 error = EINVAL;
1650 mtx_unlock(&nd6_mtx);
1651 break;
1652 }
1653 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1654 nbi->state = ln->ln_state;
1655 nbi->asked = ln->ln_asked;
1656 nbi->isrouter = ln->ln_router;
1657 nbi->expire = ln->ln_expire;
1658 mtx_unlock(&nd6_mtx);
1659
1660 break;
1661 }
1662 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1663 ndif->ifindex = nd6_defifindex;
1664 break;
1665 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1666 return (nd6_setdefaultiface(ndif->ifindex));
1667 }
1668 return (error);
1669 }
1670
1671 /*
1672 * Create neighbor cache entry and cache link-layer address,
1673 * on reception of inbound ND6 packets. (RS/RA/NS/redirect)
1674 */
1675 struct rtentry *
nd6_cache_lladdr(struct ifnet * ifp,struct in6_addr * from,char * lladdr,int lladdrlen,int type,int code)1676 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr,
1677 int lladdrlen,
1678 int type, /* ICMP6 type */
1679 int code /* type dependent information */)
1680 {
1681 struct rtentry *rt = NULL;
1682 struct llinfo_nd6 *ln = NULL;
1683 int is_newentry;
1684 struct sockaddr_dl *sdl = NULL;
1685 int do_update;
1686 int olladdr;
1687 int llchange;
1688 int newstate = 0;
1689
1690 if (!ifp)
1691 panic("ifp == NULL in nd6_cache_lladdr");
1692 if (!from)
1693 panic("from == NULL in nd6_cache_lladdr");
1694
1695 /* nothing must be updated for unspecified address */
1696 if (IN6_IS_ADDR_UNSPECIFIED(from))
1697 return NULL;
1698
1699 /*
1700 * Validation about ifp->if_addrlen and lladdrlen must be done in
1701 * the caller.
1702 *
1703 * XXX If the link does not have link-layer adderss, what should
1704 * we do? (ifp->if_addrlen == 0)
1705 * Spec says nothing in sections for RA, RS and NA. There's small
1706 * description on it in NS section (RFC 2461 7.2.3).
1707 */
1708
1709 rt = nd6_lookup(from, 0, ifp);
1710 if (!rt) {
1711 #if 0
1712 /* nothing must be done if there's no lladdr */
1713 if (!lladdr || !lladdrlen)
1714 return NULL;
1715 #endif
1716
1717 rt = nd6_lookup(from, 1, ifp);
1718 is_newentry = 1;
1719 } else {
1720 /* do nothing if static ndp is set */
1721 if (rt->rt_flags & RTF_STATIC)
1722 return NULL;
1723 is_newentry = 0;
1724 }
1725
1726 if (!rt)
1727 return NULL;
1728 if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) {
1729 fail:
1730 nd6_free(rt);
1731 return NULL;
1732 }
1733 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1734 if (!ln)
1735 goto fail;
1736 if (!rt->rt_gateway)
1737 goto fail;
1738 if (rt->rt_gateway->sa_family != AF_LINK)
1739 goto fail;
1740 sdl = SDL(rt->rt_gateway);
1741
1742 olladdr = (sdl->sdl_alen) ? 1 : 0;
1743 if (olladdr && lladdr) {
1744 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
1745 llchange = 1;
1746 else
1747 llchange = 0;
1748 } else
1749 llchange = 0;
1750
1751 /*
1752 * newentry olladdr lladdr llchange (*=record)
1753 * 0 n n -- (1)
1754 * 0 y n -- (2)
1755 * 0 n y -- (3) * STALE
1756 * 0 y y n (4) *
1757 * 0 y y y (5) * STALE
1758 * 1 -- n -- (6) NOSTATE(= PASSIVE)
1759 * 1 -- y -- (7) * STALE
1760 */
1761
1762 if (lladdr) { /* (3-5) and (7) */
1763 /*
1764 * Record source link-layer address
1765 * XXX is it dependent to ifp->if_type?
1766 */
1767 sdl->sdl_alen = ifp->if_addrlen;
1768 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
1769 }
1770
1771 if (!is_newentry) {
1772 if ((!olladdr && lladdr) || /* (3) */
1773 (olladdr && lladdr && llchange)) { /* (5) */
1774 do_update = 1;
1775 newstate = ND6_LLINFO_STALE;
1776 } else { /* (1-2,4) */
1777 do_update = 0;
1778 }
1779 } else {
1780 do_update = 1;
1781 if (!lladdr) /* (6) */
1782 newstate = ND6_LLINFO_NOSTATE;
1783 else /* (7) */
1784 newstate = ND6_LLINFO_STALE;
1785 }
1786
1787 if (do_update) {
1788 /*
1789 * Update the state of the neighbor cache.
1790 */
1791 ln->ln_state = newstate;
1792
1793 if (ln->ln_state == ND6_LLINFO_STALE) {
1794 /*
1795 * XXX: since nd6_output() below will cause
1796 * state tansition to DELAY and reset the timer,
1797 * we must set the timer now, although it is actually
1798 * meaningless.
1799 */
1800 ln->ln_expire = time_uptime + nd6_gctimer;
1801
1802 if (ln->ln_hold) {
1803 /*
1804 * we assume ifp is not a p2p here, so just
1805 * set the 2nd argument as the 1st one.
1806 */
1807 nd6_output(ifp, ifp, ln->ln_hold,
1808 (struct sockaddr_in6 *)rt_key(rt), rt);
1809 ln->ln_hold = NULL;
1810 }
1811 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
1812 /* probe right away */
1813 ln->ln_expire = time_uptime;
1814 }
1815 }
1816
1817 /*
1818 * ICMP6 type dependent behavior.
1819 *
1820 * NS: clear IsRouter if new entry
1821 * RS: clear IsRouter
1822 * RA: set IsRouter if there's lladdr
1823 * redir: clear IsRouter if new entry
1824 *
1825 * RA case, (1):
1826 * The spec says that we must set IsRouter in the following cases:
1827 * - If lladdr exist, set IsRouter. This means (1-5).
1828 * - If it is old entry (!newentry), set IsRouter. This means (7).
1829 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1830 * A quetion arises for (1) case. (1) case has no lladdr in the
1831 * neighbor cache, this is similar to (6).
1832 * This case is rare but we figured that we MUST NOT set IsRouter.
1833 *
1834 * newentry olladdr lladdr llchange NS RS RA redir
1835 * D R
1836 * 0 n n -- (1) c ? s
1837 * 0 y n -- (2) c s s
1838 * 0 n y -- (3) c s s
1839 * 0 y y n (4) c s s
1840 * 0 y y y (5) c s s
1841 * 1 -- n -- (6) c c c s
1842 * 1 -- y -- (7) c c s c s
1843 *
1844 * (c=clear s=set)
1845 */
1846 switch (type & 0xff) {
1847 case ND_NEIGHBOR_SOLICIT:
1848 /*
1849 * New entry must have is_router flag cleared.
1850 */
1851 if (is_newentry) /* (6-7) */
1852 ln->ln_router = 0;
1853 break;
1854 case ND_REDIRECT:
1855 /*
1856 * If the icmp is a redirect to a better router, always set the
1857 * is_router flag. Otherwise, if the entry is newly created,
1858 * clear the flag. [RFC 2461, sec 8.3]
1859 */
1860 if (code == ND_REDIRECT_ROUTER)
1861 ln->ln_router = 1;
1862 else if (is_newentry) /* (6-7) */
1863 ln->ln_router = 0;
1864 break;
1865 case ND_ROUTER_SOLICIT:
1866 /*
1867 * is_router flag must always be cleared.
1868 */
1869 ln->ln_router = 0;
1870 break;
1871 case ND_ROUTER_ADVERT:
1872 /*
1873 * Mark an entry with lladdr as a router.
1874 */
1875 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */
1876 (is_newentry && lladdr)) { /* (7) */
1877 ln->ln_router = 1;
1878 }
1879 break;
1880 }
1881
1882 if (llchange || lladdr)
1883 rt_rtmsg(llchange ? RTM_CHANGE : RTM_ADD, rt, rt->rt_ifp, 0);
1884
1885 /*
1886 * When the link-layer address of a router changes, select the
1887 * best router again. In particular, when the neighbor entry is newly
1888 * created, it might affect the selection policy.
1889 * Question: can we restrict the first condition to the "is_newentry"
1890 * case?
1891 * XXX: when we hear an RA from a new router with the link-layer
1892 * address option, defrouter_select() is called twice, since
1893 * defrtrlist_update called the function as well. However, I believe
1894 * we can compromise the overhead, since it only happens the first
1895 * time.
1896 * XXX: although defrouter_select() should not have a bad effect
1897 * for those are not autoconfigured hosts, we explicitly avoid such
1898 * cases for safety.
1899 */
1900 if (do_update && ln->ln_router && !ip6_forwarding &&
1901 (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV))
1902 defrouter_select();
1903
1904 return rt;
1905 }
1906
1907 static void
nd6_slowtimo(void * arg __unused)1908 nd6_slowtimo(void *arg __unused)
1909 {
1910 struct lwkt_msg *lmsg = &nd6_slowtimo_netmsg.lmsg;
1911
1912 KASSERT(mycpuid == 0, ("not on cpu0"));
1913 crit_enter();
1914 if (lmsg->ms_flags & MSGF_DONE)
1915 lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg);
1916 crit_exit();
1917 }
1918
1919 static void
nd6_slowtimo_dispatch(netmsg_t nmsg)1920 nd6_slowtimo_dispatch(netmsg_t nmsg)
1921 {
1922 const struct ifnet_array *arr;
1923 struct nd_ifinfo *nd6if;
1924 int i;
1925
1926 ASSERT_NETISR0;
1927
1928 crit_enter();
1929 lwkt_replymsg(&nmsg->lmsg, 0); /* reply ASAP */
1930 crit_exit();
1931
1932 arr = ifnet_array_get();
1933
1934 mtx_lock(&nd6_mtx);
1935 for (i = 0; i < arr->ifnet_count; ++i) {
1936 struct ifnet *ifp = arr->ifnet_arr[i];
1937
1938 if (ifp->if_afdata[AF_INET6] == NULL)
1939 continue;
1940 nd6if = ND_IFINFO(ifp);
1941 if (nd6if->basereachable && /* already initialized */
1942 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
1943 /*
1944 * Since reachable time rarely changes by router
1945 * advertisements, we SHOULD insure that a new random
1946 * value gets recomputed at least once every few hours.
1947 * (RFC 2461, 6.3.4)
1948 */
1949 nd6if->recalctm = nd6_recalc_reachtm_interval;
1950 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
1951 }
1952 }
1953 mtx_unlock(&nd6_mtx);
1954
1955 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
1956 nd6_slowtimo, NULL);
1957 }
1958
1959 int
nd6_output(struct ifnet * ifp,struct ifnet * origifp,struct mbuf * m,struct sockaddr_in6 * dst,struct rtentry * rt)1960 nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1961 struct sockaddr_in6 *dst, struct rtentry *rt)
1962 {
1963 int error;
1964
1965 if (ifp->if_flags & IFF_LOOPBACK)
1966 error = ifp->if_output(origifp, m, (struct sockaddr *)dst, rt);
1967 else
1968 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, rt);
1969 return error;
1970 }
1971
1972 int
nd6_resolve(struct ifnet * ifp,struct rtentry * rt0,struct mbuf * m,struct sockaddr * dst0,u_char * desten)1973 nd6_resolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
1974 struct sockaddr *dst0, u_char *desten)
1975 {
1976 struct sockaddr_in6 *dst = SIN6(dst0);
1977 struct rtentry *rt = NULL;
1978 struct llinfo_nd6 *ln = NULL;
1979 int error;
1980
1981 if (m->m_flags & M_MCAST) {
1982 switch (ifp->if_type) {
1983 case IFT_ETHER:
1984 #ifdef IFT_L2VLAN
1985 case IFT_L2VLAN:
1986 #endif
1987 #ifdef IFT_IEEE80211
1988 case IFT_IEEE80211:
1989 #endif
1990 ETHER_MAP_IPV6_MULTICAST(&dst->sin6_addr,
1991 desten);
1992 return 0;
1993 case IFT_IEEE1394:
1994 bcopy(ifp->if_broadcastaddr, desten, ifp->if_addrlen);
1995 return 0;
1996 default:
1997 error = EAFNOSUPPORT;
1998 goto bad;
1999 }
2000 }
2001
2002 if (rt0 != NULL) {
2003 error = rt_llroute(dst0, rt0, &rt);
2004 if (error != 0)
2005 goto bad;
2006 ln = rt->rt_llinfo;
2007 }
2008
2009 /*
2010 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
2011 * the condition below is not very efficient. But we believe
2012 * it is tolerable, because this should be a rare case.
2013 */
2014 if (ln == NULL && nd6_is_addr_neighbor(dst, ifp)) {
2015 rt = nd6_lookup(&dst->sin6_addr, 1, ifp);
2016 if (rt != NULL)
2017 ln = rt->rt_llinfo;
2018 }
2019
2020 if (ln == NULL || rt == NULL) {
2021 if (!(ifp->if_flags & IFF_POINTOPOINT) &&
2022 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) {
2023 log(LOG_DEBUG,
2024 "nd6_output: can't allocate llinfo for %s "
2025 "(ln=%p, rt=%p)\n",
2026 ip6_sprintf(&dst->sin6_addr), ln, rt);
2027 error = ENOBUFS;
2028 goto bad;
2029 }
2030 return 0;
2031 }
2032
2033 /* We don't have to do link-layer address resolution on a p2p link. */
2034 if ((ifp->if_flags & IFF_POINTOPOINT) &&
2035 ln->ln_state < ND6_LLINFO_REACHABLE) {
2036 ln->ln_state = ND6_LLINFO_STALE;
2037 ln->ln_expire = time_uptime + nd6_gctimer;
2038 }
2039
2040 /*
2041 * The first time we send a packet to a neighbor whose entry is
2042 * STALE, we have to change the state to DELAY and a sets a timer to
2043 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
2044 * neighbor unreachability detection on expiration.
2045 * (RFC 2461 7.3.3)
2046 */
2047 if (ln->ln_state == ND6_LLINFO_STALE) {
2048 ln->ln_asked = 0;
2049 ln->ln_state = ND6_LLINFO_DELAY;
2050 ln->ln_expire = time_uptime + nd6_delay;
2051 }
2052
2053 /*
2054 * If the neighbor cache entry has a state other than INCOMPLETE
2055 * (i.e. its link-layer address is already resolved), return it.
2056 */
2057 if (ln->ln_state > ND6_LLINFO_INCOMPLETE) {
2058 struct sockaddr_dl *sdl = SDL(rt->rt_gateway);
2059
2060 KKASSERT(sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0);
2061 bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
2062 return 0;
2063 }
2064
2065 /*
2066 * There is a neighbor cache entry, but no ethernet address
2067 * response yet. Replace the held mbuf (if any) with this
2068 * latest one.
2069 */
2070 if (ln->ln_hold)
2071 m_freem(ln->ln_hold);
2072 ln->ln_hold = m;
2073
2074 /*
2075 * This code conforms to the rate-limiting rule described in Section
2076 * 7.2.2 of RFC 2461, because the timer is set correctly after sending
2077 * an NS below.
2078 */
2079 if (ln->ln_state == ND6_LLINFO_NOSTATE ||
2080 ln->ln_state == ND6_LLINFO_WAITDELETE) {
2081 /*
2082 * This neighbor cache entry was just created; change its
2083 * state to INCOMPLETE and start its life cycle.
2084 *
2085 * We force an NS output below by setting ln_expire to 1
2086 * (nd6_rtrequest() could set it to the current time_uptime)
2087 * and zeroing out ln_asked (XXX this may not be necessary).
2088 */
2089 ln->ln_state = ND6_LLINFO_INCOMPLETE;
2090 ln->ln_expire = 1;
2091 ln->ln_asked = 0;
2092 }
2093 if (ln->ln_expire && ln->ln_expire < time_uptime && ln->ln_asked == 0) {
2094 ln->ln_asked++;
2095 ln->ln_expire = time_uptime + ND_IFINFO(ifp)->retrans / 1000;
2096 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0);
2097 }
2098
2099 if (ln->ln_asked >= nd6_mmaxtries)
2100 return (rt != NULL && rt->rt_flags & RTF_GATEWAY) ?
2101 EHOSTUNREACH : EHOSTDOWN;
2102 return EWOULDBLOCK;
2103
2104 bad:
2105 m_freem(m);
2106 return error;
2107 }
2108
2109 int
nd6_need_cache(struct ifnet * ifp)2110 nd6_need_cache(struct ifnet *ifp)
2111 {
2112 /*
2113 * XXX: we currently do not make neighbor cache on any interface
2114 * other than Ethernet and GIF.
2115 *
2116 * RFC2893 says:
2117 * - unidirectional tunnels needs no ND
2118 */
2119 switch (ifp->if_type) {
2120 case IFT_ETHER:
2121 case IFT_IEEE1394:
2122 #ifdef IFT_L2VLAN
2123 case IFT_L2VLAN:
2124 #endif
2125 #ifdef IFT_IEEE80211
2126 case IFT_IEEE80211:
2127 #endif
2128 #ifdef IFT_CARP
2129 case IFT_CARP:
2130 #endif
2131 case IFT_GIF: /* XXX need more cases? */
2132 return (1);
2133 default:
2134 return (0);
2135 }
2136 }
2137
2138 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
2139 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
2140 #ifdef SYSCTL_DECL
2141 SYSCTL_DECL(_net_inet6_icmp6);
2142 #endif
2143 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2144 CTLFLAG_RD, nd6_sysctl_drlist, "List default routers");
2145 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
2146 CTLFLAG_RD, nd6_sysctl_prlist, "List prefixes");
2147
2148 static int
nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)2149 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2150 {
2151 int error;
2152 char buf[1024];
2153 struct in6_defrouter *d, *de;
2154 struct nd_defrouter *dr;
2155
2156 if (req->newptr)
2157 return EPERM;
2158 error = 0;
2159
2160 for (dr = TAILQ_FIRST(&nd_defrouter); dr;
2161 dr = TAILQ_NEXT(dr, dr_entry)) {
2162 d = (struct in6_defrouter *)buf;
2163 de = (struct in6_defrouter *)(buf + sizeof(buf));
2164
2165 if (d + 1 <= de) {
2166 bzero(d, sizeof(*d));
2167 d->rtaddr.sin6_family = AF_INET6;
2168 d->rtaddr.sin6_len = sizeof(d->rtaddr);
2169 if (in6_recoverscope(&d->rtaddr, &dr->rtaddr,
2170 dr->ifp) != 0)
2171 log(LOG_ERR,
2172 "scope error in "
2173 "default router list (%s)\n",
2174 ip6_sprintf(&dr->rtaddr));
2175 d->flags = dr->flags;
2176 d->rtlifetime = dr->rtlifetime;
2177 d->expire = dr->expire;
2178 d->if_index = dr->ifp->if_index;
2179 } else
2180 panic("buffer too short");
2181
2182 error = SYSCTL_OUT(req, buf, sizeof(*d));
2183 if (error)
2184 break;
2185 }
2186 return error;
2187 }
2188
2189 static int
nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)2190 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
2191 {
2192 int error;
2193 char buf[1024];
2194 struct in6_prefix *p, *pe;
2195 struct nd_prefix *pr;
2196
2197 if (req->newptr)
2198 return EPERM;
2199 error = 0;
2200
2201 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
2202 u_short advrtrs;
2203 size_t advance;
2204 struct sockaddr_in6 *sin6, *s6;
2205 struct nd_pfxrouter *pfr;
2206
2207 p = (struct in6_prefix *)buf;
2208 pe = (struct in6_prefix *)(buf + sizeof(buf));
2209
2210 if (p + 1 <= pe) {
2211 bzero(p, sizeof(*p));
2212 sin6 = (struct sockaddr_in6 *)(p + 1);
2213
2214 p->prefix = pr->ndpr_prefix;
2215 if (in6_recoverscope(&p->prefix,
2216 &p->prefix.sin6_addr, pr->ndpr_ifp) != 0)
2217 log(LOG_ERR,
2218 "scope error in prefix list (%s)\n",
2219 ip6_sprintf(&p->prefix.sin6_addr));
2220 p->raflags = pr->ndpr_raf;
2221 p->prefixlen = pr->ndpr_plen;
2222 p->vltime = pr->ndpr_vltime;
2223 p->pltime = pr->ndpr_pltime;
2224 p->if_index = pr->ndpr_ifp->if_index;
2225 p->expire = pr->ndpr_expire;
2226 p->refcnt = pr->ndpr_refcnt;
2227 p->flags = pr->ndpr_stateflags;
2228 p->origin = PR_ORIG_RA;
2229 advrtrs = 0;
2230 for (pfr = pr->ndpr_advrtrs.lh_first; pfr;
2231 pfr = pfr->pfr_next) {
2232 if ((void *)&sin6[advrtrs + 1] > (void *)pe) {
2233 advrtrs++;
2234 continue;
2235 }
2236 s6 = &sin6[advrtrs];
2237 bzero(s6, sizeof(*s6));
2238 s6->sin6_family = AF_INET6;
2239 s6->sin6_len = sizeof(*sin6);
2240 if (in6_recoverscope(s6, &pfr->router->rtaddr,
2241 pfr->router->ifp) != 0)
2242 log(LOG_ERR,
2243 "scope error in "
2244 "prefix list (%s)\n",
2245 ip6_sprintf(&pfr->router->rtaddr));
2246 advrtrs++;
2247 }
2248 p->advrtrs = advrtrs;
2249 } else {
2250 panic("buffer too short");
2251 }
2252
2253 advance = sizeof(*p) + sizeof(*sin6) * advrtrs;
2254 error = SYSCTL_OUT(req, buf, advance);
2255 if (error)
2256 break;
2257 }
2258 return error;
2259 }
2260