FreeBSD/Linux Kernel Cross Reference
sys/netinet6/nd6.c
1 /*-
2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD: releng/10.4/sys/netinet6/nd6.c 303458 2016-07-28 20:08:01Z sbruno $");
34
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 #include "opt_kdtrace.h"
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/callout.h>
42 #include <sys/malloc.h>
43 #include <sys/mbuf.h>
44 #include <sys/socket.h>
45 #include <sys/sockio.h>
46 #include <sys/time.h>
47 #include <sys/kernel.h>
48 #include <sys/protosw.h>
49 #include <sys/errno.h>
50 #include <sys/syslog.h>
51 #include <sys/lock.h>
52 #include <sys/rwlock.h>
53 #include <sys/queue.h>
54 #include <sys/sdt.h>
55 #include <sys/sysctl.h>
56
57 #include <net/if.h>
58 #include <net/if_arc.h>
59 #include <net/if_dl.h>
60 #include <net/if_types.h>
61 #include <net/iso88025.h>
62 #include <net/fddi.h>
63 #include <net/route.h>
64 #include <net/vnet.h>
65
66 #include <netinet/in.h>
67 #include <netinet/in_kdtrace.h>
68 #include <net/if_llatbl.h>
69 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le))
70 #include <netinet/if_ether.h>
71 #include <netinet6/in6_var.h>
72 #include <netinet/ip6.h>
73 #include <netinet6/ip6_var.h>
74 #include <netinet6/scope6_var.h>
75 #include <netinet6/nd6.h>
76 #include <netinet6/in6_ifattach.h>
77 #include <netinet/icmp6.h>
78 #include <netinet6/send.h>
79
80 #include <sys/limits.h>
81
82 #include <security/mac/mac_framework.h>
83
84 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
85 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
86
87 #define SIN6(s) ((const struct sockaddr_in6 *)(s))
88
89 /* timer values */
90 VNET_DEFINE(int, nd6_prune) = 1; /* walk list every 1 seconds */
91 VNET_DEFINE(int, nd6_delay) = 5; /* delay first probe time 5 second */
92 VNET_DEFINE(int, nd6_umaxtries) = 3; /* maximum unicast query */
93 VNET_DEFINE(int, nd6_mmaxtries) = 3; /* maximum multicast query */
94 VNET_DEFINE(int, nd6_useloopback) = 1; /* use loopback interface for
95 * local traffic */
96 VNET_DEFINE(int, nd6_gctimer) = (60 * 60 * 24); /* 1 day: garbage
97 * collection timer */
98
99 /* preventing too many loops in ND option parsing */
100 static VNET_DEFINE(int, nd6_maxndopt) = 10; /* max # of ND options allowed */
101
102 VNET_DEFINE(int, nd6_maxnudhint) = 0; /* max # of subsequent upper
103 * layer hints */
104 static VNET_DEFINE(int, nd6_maxqueuelen) = 1; /* max pkts cached in unresolved
105 * ND entries */
106 #define V_nd6_maxndopt VNET(nd6_maxndopt)
107 #define V_nd6_maxqueuelen VNET(nd6_maxqueuelen)
108
109 #ifdef ND6_DEBUG
110 VNET_DEFINE(int, nd6_debug) = 1;
111 #else
112 VNET_DEFINE(int, nd6_debug) = 0;
113 #endif
114
115 VNET_DEFINE(struct nd_drhead, nd_defrouter);
116 VNET_DEFINE(struct nd_prhead, nd_prefix);
117 VNET_DEFINE(struct rwlock, nd6_lock);
118
119 VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL;
120 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval)
121
122 int (*send_sendso_input_hook)(struct mbuf *, struct ifnet *, int, int);
123
124 static int nd6_is_new_addr_neighbor(struct sockaddr_in6 *,
125 struct ifnet *);
126 static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *);
127 static void nd6_slowtimo(void *);
128 static int regen_tmpaddr(struct in6_ifaddr *);
129 static struct llentry *nd6_free(struct llentry **, int);
130 static void nd6_llinfo_timer(void *);
131 static void clear_llinfo_pqueue(struct llentry *);
132 static int nd6_output_lle(struct ifnet *, struct ifnet *, struct mbuf *,
133 struct sockaddr_in6 *);
134 static int nd6_output_ifp(struct ifnet *, struct ifnet *, struct mbuf *,
135 struct sockaddr_in6 *);
136
137 static VNET_DEFINE(struct callout, nd6_slowtimo_ch);
138 #define V_nd6_slowtimo_ch VNET(nd6_slowtimo_ch)
139
140 VNET_DEFINE(struct callout, nd6_timer_ch);
141
142 void
143 nd6_init(void)
144 {
145
146 rw_init(&V_nd6_lock, "nd6");
147
148 LIST_INIT(&V_nd_prefix);
149
150 /* initialization of the default router list */
151 TAILQ_INIT(&V_nd_defrouter);
152
153 /* start timer */
154 callout_init(&V_nd6_slowtimo_ch, 0);
155 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
156 nd6_slowtimo, curvnet);
157
158 nd6_dad_init();
159 }
160
161 #ifdef VIMAGE
162 void
163 nd6_destroy()
164 {
165
166 callout_drain(&V_nd6_slowtimo_ch);
167 callout_drain(&V_nd6_timer_ch);
168 rw_destroy(&V_nd6_lock);
169 }
170 #endif
171
172 struct nd_ifinfo *
173 nd6_ifattach(struct ifnet *ifp)
174 {
175 struct nd_ifinfo *nd;
176
177 nd = malloc(sizeof(*nd), M_IP6NDP, M_WAITOK | M_ZERO);
178 nd->initialized = 1;
179
180 nd->chlim = IPV6_DEFHLIM;
181 nd->basereachable = REACHABLE_TIME;
182 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable);
183 nd->retrans = RETRANS_TIMER;
184
185 nd->flags = ND6_IFF_PERFORMNUD;
186
187 /* A loopback interface always has ND6_IFF_AUTO_LINKLOCAL.
188 * XXXHRS: Clear ND6_IFF_AUTO_LINKLOCAL on an IFT_BRIDGE interface by
189 * default regardless of the V_ip6_auto_linklocal configuration to
190 * give a reasonable default behavior.
191 */
192 if ((V_ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) ||
193 (ifp->if_flags & IFF_LOOPBACK))
194 nd->flags |= ND6_IFF_AUTO_LINKLOCAL;
195 /*
196 * A loopback interface does not need to accept RTADV.
197 * XXXHRS: Clear ND6_IFF_ACCEPT_RTADV on an IFT_BRIDGE interface by
198 * default regardless of the V_ip6_accept_rtadv configuration to
199 * prevent the interface from accepting RA messages arrived
200 * on one of the member interfaces with ND6_IFF_ACCEPT_RTADV.
201 */
202 if (V_ip6_accept_rtadv &&
203 !(ifp->if_flags & IFF_LOOPBACK) &&
204 (ifp->if_type != IFT_BRIDGE))
205 nd->flags |= ND6_IFF_ACCEPT_RTADV;
206 if (V_ip6_no_radr && !(ifp->if_flags & IFF_LOOPBACK))
207 nd->flags |= ND6_IFF_NO_RADR;
208
209 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
210 nd6_setmtu0(ifp, nd);
211
212 return nd;
213 }
214
215 void
216 nd6_ifdetach(struct nd_ifinfo *nd)
217 {
218
219 free(nd, M_IP6NDP);
220 }
221
222 /*
223 * Reset ND level link MTU. This function is called when the physical MTU
224 * changes, which means we might have to adjust the ND level MTU.
225 */
226 void
227 nd6_setmtu(struct ifnet *ifp)
228 {
229 if (ifp->if_afdata[AF_INET6] == NULL)
230 return;
231
232 nd6_setmtu0(ifp, ND_IFINFO(ifp));
233 }
234
235 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
236 void
237 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi)
238 {
239 u_int32_t omaxmtu;
240
241 omaxmtu = ndi->maxmtu;
242
243 switch (ifp->if_type) {
244 case IFT_ARCNET:
245 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */
246 break;
247 case IFT_FDDI:
248 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); /* RFC2467 */
249 break;
250 case IFT_ISO88025:
251 ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu);
252 break;
253 default:
254 ndi->maxmtu = ifp->if_mtu;
255 break;
256 }
257
258 /*
259 * Decreasing the interface MTU under IPV6 minimum MTU may cause
260 * undesirable situation. We thus notify the operator of the change
261 * explicitly. The check for omaxmtu is necessary to restrict the
262 * log to the case of changing the MTU, not initializing it.
263 */
264 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) {
265 log(LOG_NOTICE, "nd6_setmtu0: "
266 "new link MTU on %s (%lu) is too small for IPv6\n",
267 if_name(ifp), (unsigned long)ndi->maxmtu);
268 }
269
270 if (ndi->maxmtu > V_in6_maxmtu)
271 in6_setmaxmtu(); /* check all interfaces just in case */
272
273 }
274
275 void
276 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
277 {
278
279 bzero(ndopts, sizeof(*ndopts));
280 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
281 ndopts->nd_opts_last
282 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
283
284 if (icmp6len == 0) {
285 ndopts->nd_opts_done = 1;
286 ndopts->nd_opts_search = NULL;
287 }
288 }
289
290 /*
291 * Take one ND option.
292 */
293 struct nd_opt_hdr *
294 nd6_option(union nd_opts *ndopts)
295 {
296 struct nd_opt_hdr *nd_opt;
297 int olen;
298
299 KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__));
300 KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts",
301 __func__));
302 if (ndopts->nd_opts_search == NULL)
303 return NULL;
304 if (ndopts->nd_opts_done)
305 return NULL;
306
307 nd_opt = ndopts->nd_opts_search;
308
309 /* make sure nd_opt_len is inside the buffer */
310 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) {
311 bzero(ndopts, sizeof(*ndopts));
312 return NULL;
313 }
314
315 olen = nd_opt->nd_opt_len << 3;
316 if (olen == 0) {
317 /*
318 * Message validation requires that all included
319 * options have a length that is greater than zero.
320 */
321 bzero(ndopts, sizeof(*ndopts));
322 return NULL;
323 }
324
325 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen);
326 if (ndopts->nd_opts_search > ndopts->nd_opts_last) {
327 /* option overruns the end of buffer, invalid */
328 bzero(ndopts, sizeof(*ndopts));
329 return NULL;
330 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) {
331 /* reached the end of options chain */
332 ndopts->nd_opts_done = 1;
333 ndopts->nd_opts_search = NULL;
334 }
335 return nd_opt;
336 }
337
338 /*
339 * Parse multiple ND options.
340 * This function is much easier to use, for ND routines that do not need
341 * multiple options of the same type.
342 */
343 int
344 nd6_options(union nd_opts *ndopts)
345 {
346 struct nd_opt_hdr *nd_opt;
347 int i = 0;
348
349 KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__));
350 KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts",
351 __func__));
352 if (ndopts->nd_opts_search == NULL)
353 return 0;
354
355 while (1) {
356 nd_opt = nd6_option(ndopts);
357 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) {
358 /*
359 * Message validation requires that all included
360 * options have a length that is greater than zero.
361 */
362 ICMP6STAT_INC(icp6s_nd_badopt);
363 bzero(ndopts, sizeof(*ndopts));
364 return -1;
365 }
366
367 if (nd_opt == NULL)
368 goto skip1;
369
370 switch (nd_opt->nd_opt_type) {
371 case ND_OPT_SOURCE_LINKADDR:
372 case ND_OPT_TARGET_LINKADDR:
373 case ND_OPT_MTU:
374 case ND_OPT_REDIRECTED_HEADER:
375 case ND_OPT_NONCE:
376 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
377 nd6log((LOG_INFO,
378 "duplicated ND6 option found (type=%d)\n",
379 nd_opt->nd_opt_type));
380 /* XXX bark? */
381 } else {
382 ndopts->nd_opt_array[nd_opt->nd_opt_type]
383 = nd_opt;
384 }
385 break;
386 case ND_OPT_PREFIX_INFORMATION:
387 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) {
388 ndopts->nd_opt_array[nd_opt->nd_opt_type]
389 = nd_opt;
390 }
391 ndopts->nd_opts_pi_end =
392 (struct nd_opt_prefix_info *)nd_opt;
393 break;
394 /* What about ND_OPT_ROUTE_INFO? RFC 4191 */
395 case ND_OPT_RDNSS: /* RFC 6106 */
396 case ND_OPT_DNSSL: /* RFC 6106 */
397 /*
398 * Silently ignore options we know and do not care about
399 * in the kernel.
400 */
401 break;
402 default:
403 /*
404 * Unknown options must be silently ignored,
405 * to accomodate future extension to the protocol.
406 */
407 nd6log((LOG_DEBUG,
408 "nd6_options: unsupported option %d - "
409 "option ignored\n", nd_opt->nd_opt_type));
410 }
411
412 skip1:
413 i++;
414 if (i > V_nd6_maxndopt) {
415 ICMP6STAT_INC(icp6s_nd_toomanyopt);
416 nd6log((LOG_INFO, "too many loop in nd opt\n"));
417 break;
418 }
419
420 if (ndopts->nd_opts_done)
421 break;
422 }
423
424 return 0;
425 }
426
427 /*
428 * ND6 timer routine to handle ND6 entries
429 */
430 void
431 nd6_llinfo_settimer_locked(struct llentry *ln, long tick)
432 {
433 int canceled;
434
435 LLE_WLOCK_ASSERT(ln);
436
437 if (tick < 0) {
438 ln->la_expire = 0;
439 ln->ln_ntick = 0;
440 canceled = callout_stop(&ln->ln_timer_ch);
441 } else {
442 ln->la_expire = time_uptime + tick / hz;
443 LLE_ADDREF(ln);
444 if (tick > INT_MAX) {
445 ln->ln_ntick = tick - INT_MAX;
446 canceled = callout_reset(&ln->ln_timer_ch, INT_MAX,
447 nd6_llinfo_timer, ln);
448 } else {
449 ln->ln_ntick = 0;
450 canceled = callout_reset(&ln->ln_timer_ch, tick,
451 nd6_llinfo_timer, ln);
452 }
453 }
454 if (canceled)
455 LLE_REMREF(ln);
456 }
457
458 void
459 nd6_llinfo_settimer(struct llentry *ln, long tick)
460 {
461
462 LLE_WLOCK(ln);
463 nd6_llinfo_settimer_locked(ln, tick);
464 LLE_WUNLOCK(ln);
465 }
466
467 static void
468 nd6_llinfo_timer(void *arg)
469 {
470 struct llentry *ln;
471 struct in6_addr *dst;
472 struct ifnet *ifp;
473 struct nd_ifinfo *ndi;
474
475 KASSERT(arg != NULL, ("%s: arg NULL", __func__));
476 ln = (struct llentry *)arg;
477 ifp = ln->lle_tbl->llt_ifp;
478 CURVNET_SET(ifp->if_vnet);
479
480 ND6_RLOCK();
481 LLE_WLOCK(ln);
482 if (callout_pending(&ln->la_timer)) {
483 /*
484 * Here we are a bit odd here in the treatment of
485 * active/pending. If the pending bit is set, it got
486 * rescheduled before I ran. The active
487 * bit we ignore, since if it was stopped
488 * in ll_tablefree() and was currently running
489 * it would have return 0 so the code would
490 * not have deleted it since the callout could
491 * not be stopped so we want to go through
492 * with the delete here now. If the callout
493 * was restarted, the pending bit will be back on and
494 * we just want to bail since the callout_reset would
495 * return 1 and our reference would have been removed
496 * by nd6_llinfo_settimer_locked above since canceled
497 * would have been 1.
498 */
499 LLE_WUNLOCK(ln);
500 ND6_RUNLOCK();
501 CURVNET_RESTORE();
502 return;
503 }
504
505 if (ln->ln_ntick > 0) {
506 if (ln->ln_ntick > INT_MAX) {
507 ln->ln_ntick -= INT_MAX;
508 nd6_llinfo_settimer_locked(ln, INT_MAX);
509 } else {
510 ln->ln_ntick = 0;
511 nd6_llinfo_settimer_locked(ln, ln->ln_ntick);
512 }
513 goto done;
514 }
515
516 ndi = ND_IFINFO(ifp);
517 dst = &L3_ADDR_SIN6(ln)->sin6_addr;
518 if (ln->la_flags & LLE_STATIC) {
519 goto done;
520 }
521
522 if (ln->la_flags & LLE_DELETED) {
523 (void)nd6_free(&ln, 0);
524 goto done;
525 }
526
527 switch (ln->ln_state) {
528 case ND6_LLINFO_INCOMPLETE:
529 if (ln->la_asked < V_nd6_mmaxtries) {
530 ln->la_asked++;
531 nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
532 LLE_WUNLOCK(ln);
533 nd6_ns_output(ifp, NULL, dst, ln, NULL);
534 LLE_WLOCK(ln);
535 } else {
536 struct mbuf *m = ln->la_hold;
537 if (m) {
538 struct mbuf *m0;
539
540 /*
541 * assuming every packet in la_hold has the
542 * same IP header. Send error after unlock.
543 */
544 m0 = m->m_nextpkt;
545 m->m_nextpkt = NULL;
546 ln->la_hold = m0;
547 clear_llinfo_pqueue(ln);
548 }
549 (void)nd6_free(&ln, 0);
550 if (m != NULL)
551 icmp6_error2(m, ICMP6_DST_UNREACH,
552 ICMP6_DST_UNREACH_ADDR, 0, ifp);
553 }
554 break;
555 case ND6_LLINFO_REACHABLE:
556 if (!ND6_LLINFO_PERMANENT(ln)) {
557 ln->ln_state = ND6_LLINFO_STALE;
558 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
559 }
560 break;
561
562 case ND6_LLINFO_STALE:
563 /* Garbage Collection(RFC 2461 5.3) */
564 if (!ND6_LLINFO_PERMANENT(ln)) {
565 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED);
566 (void)nd6_free(&ln, 1);
567 ln = NULL;
568 }
569 break;
570
571 case ND6_LLINFO_DELAY:
572 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) {
573 /* We need NUD */
574 ln->la_asked = 1;
575 ln->ln_state = ND6_LLINFO_PROBE;
576 nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
577 LLE_WUNLOCK(ln);
578 nd6_ns_output(ifp, dst, dst, ln, NULL);
579 LLE_WLOCK(ln);
580 } else {
581 ln->ln_state = ND6_LLINFO_STALE; /* XXX */
582 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
583 }
584 break;
585 case ND6_LLINFO_PROBE:
586 if (ln->la_asked < V_nd6_umaxtries) {
587 ln->la_asked++;
588 nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000);
589 LLE_WUNLOCK(ln);
590 nd6_ns_output(ifp, dst, dst, ln, NULL);
591 LLE_WLOCK(ln);
592 } else {
593 (void)nd6_free(&ln, 0);
594 }
595 break;
596 default:
597 panic("%s: paths in a dark night can be confusing: %d",
598 __func__, ln->ln_state);
599 }
600 done:
601 if (ln != NULL) {
602 ND6_RUNLOCK();
603 LLE_FREE_LOCKED(ln);
604 }
605 CURVNET_RESTORE();
606 }
607
608
609 /*
610 * ND6 timer routine to expire default route list and prefix list
611 */
612 void
613 nd6_timer(void *arg)
614 {
615 CURVNET_SET((struct vnet *) arg);
616 struct nd_drhead drq;
617 struct nd_defrouter *dr, *ndr;
618 struct nd_prefix *pr, *npr;
619 struct in6_ifaddr *ia6, *nia6;
620
621 callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz,
622 nd6_timer, curvnet);
623
624 TAILQ_INIT(&drq);
625
626 /* expire default router list */
627 ND6_WLOCK();
628 TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr)
629 if (dr->expire && dr->expire < time_uptime)
630 defrouter_unlink(dr, &drq);
631 ND6_WUNLOCK();
632
633 while ((dr = TAILQ_FIRST(&drq)) != NULL) {
634 TAILQ_REMOVE(&drq, dr, dr_entry);
635 defrouter_del(dr);
636 }
637
638 /*
639 * expire interface addresses.
640 * in the past the loop was inside prefix expiry processing.
641 * However, from a stricter speci-confrmance standpoint, we should
642 * rather separate address lifetimes and prefix lifetimes.
643 *
644 * XXXRW: in6_ifaddrhead locking.
645 */
646 addrloop:
647 TAILQ_FOREACH_SAFE(ia6, &V_in6_ifaddrhead, ia_link, nia6) {
648 /* check address lifetime */
649 if (IFA6_IS_INVALID(ia6)) {
650 int regen = 0;
651
652 /*
653 * If the expiring address is temporary, try
654 * regenerating a new one. This would be useful when
655 * we suspended a laptop PC, then turned it on after a
656 * period that could invalidate all temporary
657 * addresses. Although we may have to restart the
658 * loop (see below), it must be after purging the
659 * address. Otherwise, we'd see an infinite loop of
660 * regeneration.
661 */
662 if (V_ip6_use_tempaddr &&
663 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
664 if (regen_tmpaddr(ia6) == 0)
665 regen = 1;
666 }
667
668 in6_purgeaddr(&ia6->ia_ifa);
669
670 if (regen)
671 goto addrloop; /* XXX: see below */
672 } else if (IFA6_IS_DEPRECATED(ia6)) {
673 int oldflags = ia6->ia6_flags;
674
675 ia6->ia6_flags |= IN6_IFF_DEPRECATED;
676
677 /*
678 * If a temporary address has just become deprecated,
679 * regenerate a new one if possible.
680 */
681 if (V_ip6_use_tempaddr &&
682 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
683 (oldflags & IN6_IFF_DEPRECATED) == 0) {
684
685 if (regen_tmpaddr(ia6) == 0) {
686 /*
687 * A new temporary address is
688 * generated.
689 * XXX: this means the address chain
690 * has changed while we are still in
691 * the loop. Although the change
692 * would not cause disaster (because
693 * it's not a deletion, but an
694 * addition,) we'd rather restart the
695 * loop just for safety. Or does this
696 * significantly reduce performance??
697 */
698 goto addrloop;
699 }
700 }
701 } else if ((ia6->ia6_flags & IN6_IFF_TENTATIVE) != 0) {
702 /*
703 * Schedule DAD for a tentative address. This happens
704 * if the interface was down or not running
705 * when the address was configured.
706 */
707 int delay;
708
709 delay = arc4random() %
710 (MAX_RTR_SOLICITATION_DELAY * hz);
711 nd6_dad_start((struct ifaddr *)ia6, delay);
712 } else {
713 /*
714 * Check status of the interface. If it is down,
715 * mark the address as tentative for future DAD.
716 */
717 if ((ia6->ia_ifp->if_flags & IFF_UP) == 0 ||
718 (ia6->ia_ifp->if_drv_flags & IFF_DRV_RUNNING)
719 == 0 ||
720 (ND_IFINFO(ia6->ia_ifp)->flags &
721 ND6_IFF_IFDISABLED) != 0) {
722 ia6->ia6_flags &= ~IN6_IFF_DUPLICATED;
723 ia6->ia6_flags |= IN6_IFF_TENTATIVE;
724 }
725 /*
726 * A new RA might have made a deprecated address
727 * preferred.
728 */
729 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
730 }
731 }
732
733 /* expire prefix list */
734 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
735 /*
736 * check prefix lifetime.
737 * since pltime is just for autoconf, pltime processing for
738 * prefix is not necessary.
739 */
740 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME &&
741 time_uptime - pr->ndpr_lastupdate > pr->ndpr_vltime) {
742
743 /*
744 * address expiration and prefix expiration are
745 * separate. NEVER perform in6_purgeaddr here.
746 */
747 prelist_remove(pr);
748 }
749 }
750 CURVNET_RESTORE();
751 }
752
753 /*
754 * ia6 - deprecated/invalidated temporary address
755 */
756 static int
757 regen_tmpaddr(struct in6_ifaddr *ia6)
758 {
759 struct ifaddr *ifa;
760 struct ifnet *ifp;
761 struct in6_ifaddr *public_ifa6 = NULL;
762
763 ifp = ia6->ia_ifa.ifa_ifp;
764 IF_ADDR_RLOCK(ifp);
765 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
766 struct in6_ifaddr *it6;
767
768 if (ifa->ifa_addr->sa_family != AF_INET6)
769 continue;
770
771 it6 = (struct in6_ifaddr *)ifa;
772
773 /* ignore no autoconf addresses. */
774 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0)
775 continue;
776
777 /* ignore autoconf addresses with different prefixes. */
778 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
779 continue;
780
781 /*
782 * Now we are looking at an autoconf address with the same
783 * prefix as ours. If the address is temporary and is still
784 * preferred, do not create another one. It would be rare, but
785 * could happen, for example, when we resume a laptop PC after
786 * a long period.
787 */
788 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
789 !IFA6_IS_DEPRECATED(it6)) {
790 public_ifa6 = NULL;
791 break;
792 }
793
794 /*
795 * This is a public autoconf address that has the same prefix
796 * as ours. If it is preferred, keep it. We can't break the
797 * loop here, because there may be a still-preferred temporary
798 * address with the prefix.
799 */
800 if (!IFA6_IS_DEPRECATED(it6))
801 public_ifa6 = it6;
802 }
803 if (public_ifa6 != NULL)
804 ifa_ref(&public_ifa6->ia_ifa);
805 IF_ADDR_RUNLOCK(ifp);
806
807 if (public_ifa6 != NULL) {
808 int e;
809
810 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) {
811 ifa_free(&public_ifa6->ia_ifa);
812 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
813 " tmp addr,errno=%d\n", e);
814 return (-1);
815 }
816 ifa_free(&public_ifa6->ia_ifa);
817 return (0);
818 }
819
820 return (-1);
821 }
822
823 /*
824 * Nuke neighbor cache/prefix/default router management table, right before
825 * ifp goes away.
826 */
827 void
828 nd6_purge(struct ifnet *ifp)
829 {
830 struct nd_drhead drq;
831 struct nd_defrouter *dr, *ndr;
832 struct nd_prefix *pr, *npr;
833
834 TAILQ_INIT(&drq);
835
836 /*
837 * Nuke default router list entries toward ifp.
838 * We defer removal of default router list entries that is installed
839 * in the routing table, in order to keep additional side effects as
840 * small as possible.
841 */
842 ND6_WLOCK();
843 TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
844 if (dr->installed)
845 continue;
846 if (dr->ifp == ifp)
847 defrouter_unlink(dr, &drq);
848 }
849
850 TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
851 if (!dr->installed)
852 continue;
853 if (dr->ifp == ifp)
854 defrouter_unlink(dr, &drq);
855 }
856 ND6_WUNLOCK();
857
858 while ((dr = TAILQ_FIRST(&drq)) != NULL) {
859 TAILQ_REMOVE(&drq, dr, dr_entry);
860 defrouter_del(dr);
861 }
862
863 /* Nuke prefix list entries toward ifp */
864 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
865 if (pr->ndpr_ifp == ifp) {
866 /*
867 * Because if_detach() does *not* release prefixes
868 * while purging addresses the reference count will
869 * still be above zero. We therefore reset it to
870 * make sure that the prefix really gets purged.
871 */
872 pr->ndpr_refcnt = 0;
873
874 /*
875 * Previously, pr->ndpr_addr is removed as well,
876 * but I strongly believe we don't have to do it.
877 * nd6_purge() is only called from in6_ifdetach(),
878 * which removes all the associated interface addresses
879 * by itself.
880 * (jinmei@kame.net 20010129)
881 */
882 prelist_remove(pr);
883 }
884 }
885
886 /* cancel default outgoing interface setting */
887 if (V_nd6_defifindex == ifp->if_index)
888 nd6_setdefaultiface(0);
889
890 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
891 /* Refresh default router list. */
892 defrouter_select();
893 }
894
895 /* XXXXX
896 * We do not nuke the neighbor cache entries here any more
897 * because the neighbor cache is kept in if_afdata[AF_INET6].
898 * nd6_purge() is invoked by in6_ifdetach() which is called
899 * from if_detach() where everything gets purged. So let
900 * in6_domifdetach() do the actual L2 table purging work.
901 */
902 }
903
904 /*
905 * the caller acquires and releases the lock on the lltbls
906 * Returns the llentry locked
907 */
908 struct llentry *
909 nd6_lookup(struct in6_addr *addr6, int flags, struct ifnet *ifp)
910 {
911 struct sockaddr_in6 sin6;
912 struct llentry *ln;
913 int llflags;
914
915 bzero(&sin6, sizeof(sin6));
916 sin6.sin6_len = sizeof(struct sockaddr_in6);
917 sin6.sin6_family = AF_INET6;
918 sin6.sin6_addr = *addr6;
919
920 IF_AFDATA_LOCK_ASSERT(ifp);
921
922 llflags = 0;
923 if (flags & ND6_CREATE)
924 llflags |= LLE_CREATE;
925 if (flags & ND6_EXCLUSIVE)
926 llflags |= LLE_EXCLUSIVE;
927
928 ln = lla_lookup(LLTABLE6(ifp), llflags, (struct sockaddr *)&sin6);
929 if ((ln != NULL) && (llflags & LLE_CREATE))
930 ln->ln_state = ND6_LLINFO_NOSTATE;
931
932 return (ln);
933 }
934
935 /*
936 * Test whether a given IPv6 address is a neighbor or not, ignoring
937 * the actual neighbor cache. The neighbor cache is ignored in order
938 * to not reenter the routing code from within itself.
939 */
940 static int
941 nd6_is_new_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
942 {
943 struct nd_prefix *pr;
944 struct ifaddr *dstaddr;
945
946 /*
947 * A link-local address is always a neighbor.
948 * XXX: a link does not necessarily specify a single interface.
949 */
950 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) {
951 struct sockaddr_in6 sin6_copy;
952 u_int32_t zone;
953
954 /*
955 * We need sin6_copy since sa6_recoverscope() may modify the
956 * content (XXX).
957 */
958 sin6_copy = *addr;
959 if (sa6_recoverscope(&sin6_copy))
960 return (0); /* XXX: should be impossible */
961 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone))
962 return (0);
963 if (sin6_copy.sin6_scope_id == zone)
964 return (1);
965 else
966 return (0);
967 }
968
969 /*
970 * If the address matches one of our addresses,
971 * it should be a neighbor.
972 * If the address matches one of our on-link prefixes, it should be a
973 * neighbor.
974 */
975 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
976 if (pr->ndpr_ifp != ifp)
977 continue;
978
979 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) {
980 struct rtentry *rt;
981
982 /* Always use the default FIB here. */
983 rt = in6_rtalloc1((struct sockaddr *)&pr->ndpr_prefix,
984 0, 0, RT_DEFAULT_FIB);
985 if (rt == NULL)
986 continue;
987 /*
988 * This is the case where multiple interfaces
989 * have the same prefix, but only one is installed
990 * into the routing table and that prefix entry
991 * is not the one being examined here. In the case
992 * where RADIX_MPATH is enabled, multiple route
993 * entries (of the same rt_key value) will be
994 * installed because the interface addresses all
995 * differ.
996 */
997 if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
998 &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr)) {
999 RTFREE_LOCKED(rt);
1000 continue;
1001 }
1002 RTFREE_LOCKED(rt);
1003 }
1004
1005 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
1006 &addr->sin6_addr, &pr->ndpr_mask))
1007 return (1);
1008 }
1009
1010 /*
1011 * If the address is assigned on the node of the other side of
1012 * a p2p interface, the address should be a neighbor.
1013 */
1014 dstaddr = ifa_ifwithdstaddr((struct sockaddr *)addr);
1015 if (dstaddr != NULL) {
1016 if (dstaddr->ifa_ifp == ifp) {
1017 ifa_free(dstaddr);
1018 return (1);
1019 }
1020 ifa_free(dstaddr);
1021 }
1022
1023 /*
1024 * If the default router list is empty, all addresses are regarded
1025 * as on-link, and thus, as a neighbor.
1026 */
1027 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV &&
1028 TAILQ_EMPTY(&V_nd_defrouter) &&
1029 V_nd6_defifindex == ifp->if_index) {
1030 return (1);
1031 }
1032
1033 return (0);
1034 }
1035
1036
1037 /*
1038 * Detect if a given IPv6 address identifies a neighbor on a given link.
1039 * XXX: should take care of the destination of a p2p link?
1040 */
1041 int
1042 nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
1043 {
1044 struct llentry *lle;
1045 int rc = 0;
1046
1047 IF_AFDATA_UNLOCK_ASSERT(ifp);
1048 if (nd6_is_new_addr_neighbor(addr, ifp))
1049 return (1);
1050
1051 /*
1052 * Even if the address matches none of our addresses, it might be
1053 * in the neighbor cache.
1054 */
1055 IF_AFDATA_RLOCK(ifp);
1056 if ((lle = nd6_lookup(&addr->sin6_addr, 0, ifp)) != NULL) {
1057 LLE_RUNLOCK(lle);
1058 rc = 1;
1059 }
1060 IF_AFDATA_RUNLOCK(ifp);
1061 return (rc);
1062 }
1063
1064 /*
1065 * Free an nd6 llinfo entry.
1066 * Since the function would cause significant changes in the kernel, DO NOT
1067 * make it global, unless you have a strong reason for the change, and are sure
1068 * that the change is safe.
1069 */
1070 static struct llentry *
1071 nd6_free(struct llentry **lnp, int gc)
1072 {
1073 struct ifnet *ifp;
1074 struct llentry *ln, *next;
1075 struct nd_defrouter *dr;
1076
1077 ln = *lnp;
1078 *lnp = NULL;
1079
1080 LLE_WLOCK_ASSERT(ln);
1081 ND6_RLOCK_ASSERT();
1082
1083 ifp = ln->lle_tbl->llt_ifp;
1084 if ((ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) != 0)
1085 dr = defrouter_lookup_locked(&L3_ADDR_SIN6(ln)->sin6_addr, ifp);
1086 else
1087 dr = NULL;
1088 ND6_RUNLOCK();
1089
1090 if ((ln->la_flags & LLE_DELETED) == 0)
1091 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED);
1092
1093 /*
1094 * we used to have pfctlinput(PRC_HOSTDEAD) here.
1095 * even though it is not harmful, it was not really necessary.
1096 */
1097
1098 /* cancel timer */
1099 nd6_llinfo_settimer_locked(ln, -1);
1100
1101 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
1102 if (dr != NULL && dr->expire &&
1103 ln->ln_state == ND6_LLINFO_STALE && gc) {
1104 /*
1105 * If the reason for the deletion is just garbage
1106 * collection, and the neighbor is an active default
1107 * router, do not delete it. Instead, reset the GC
1108 * timer using the router's lifetime.
1109 * Simply deleting the entry would affect default
1110 * router selection, which is not necessarily a good
1111 * thing, especially when we're using router preference
1112 * values.
1113 * XXX: the check for ln_state would be redundant,
1114 * but we intentionally keep it just in case.
1115 */
1116 if (dr->expire > time_uptime)
1117 nd6_llinfo_settimer_locked(ln,
1118 (dr->expire - time_uptime) * hz);
1119 else
1120 nd6_llinfo_settimer_locked(ln,
1121 (long)V_nd6_gctimer * hz);
1122
1123 next = LIST_NEXT(ln, lle_next);
1124 LLE_REMREF(ln);
1125 LLE_WUNLOCK(ln);
1126 defrouter_rele(dr);
1127 return (next);
1128 }
1129
1130 if (dr) {
1131 /*
1132 * Unreachablity of a router might affect the default
1133 * router selection and on-link detection of advertised
1134 * prefixes.
1135 */
1136
1137 /*
1138 * Temporarily fake the state to choose a new default
1139 * router and to perform on-link determination of
1140 * prefixes correctly.
1141 * Below the state will be set correctly,
1142 * or the entry itself will be deleted.
1143 */
1144 ln->ln_state = ND6_LLINFO_INCOMPLETE;
1145 }
1146
1147 if (ln->ln_router || dr) {
1148
1149 /*
1150 * We need to unlock to avoid a LOR with rt6_flush() with the
1151 * rnh and for the calls to pfxlist_onlink_check() and
1152 * defrouter_select() in the block further down for calls
1153 * into nd6_lookup(). We still hold a ref.
1154 */
1155 LLE_WUNLOCK(ln);
1156
1157 /*
1158 * rt6_flush must be called whether or not the neighbor
1159 * is in the Default Router List.
1160 * See a corresponding comment in nd6_na_input().
1161 */
1162 rt6_flush(&L3_ADDR_SIN6(ln)->sin6_addr, ifp);
1163 }
1164
1165 if (dr) {
1166 /*
1167 * Since defrouter_select() does not affect the
1168 * on-link determination and MIP6 needs the check
1169 * before the default router selection, we perform
1170 * the check now.
1171 */
1172 pfxlist_onlink_check();
1173
1174 /*
1175 * Refresh default router list.
1176 */
1177 defrouter_select();
1178 }
1179
1180 if (ln->ln_router || dr)
1181 LLE_WLOCK(ln);
1182 }
1183
1184 /*
1185 * Before deleting the entry, remember the next entry as the
1186 * return value. We need this because pfxlist_onlink_check() above
1187 * might have freed other entries (particularly the old next entry) as
1188 * a side effect (XXX).
1189 */
1190 next = LIST_NEXT(ln, lle_next);
1191
1192 /*
1193 * Save to unlock. We still hold an extra reference and will not
1194 * free(9) in llentry_free() if someone else holds one as well.
1195 */
1196 LLE_WUNLOCK(ln);
1197 IF_AFDATA_LOCK(ifp);
1198 LLE_WLOCK(ln);
1199
1200 /* Guard against race with other llentry_free(). */
1201 if (ln->la_flags & LLE_LINKED) {
1202 LLE_REMREF(ln);
1203 llentry_free(ln);
1204 } else
1205 LLE_FREE_LOCKED(ln);
1206
1207 IF_AFDATA_UNLOCK(ifp);
1208
1209 if (dr != NULL)
1210 defrouter_rele(dr);
1211 return (next);
1212 }
1213
1214 /*
1215 * Upper-layer reachability hint for Neighbor Unreachability Detection.
1216 *
1217 * XXX cost-effective methods?
1218 */
1219 void
1220 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force)
1221 {
1222 struct llentry *ln;
1223 struct ifnet *ifp;
1224
1225 if ((dst6 == NULL) || (rt == NULL))
1226 return;
1227
1228 ifp = rt->rt_ifp;
1229 IF_AFDATA_RLOCK(ifp);
1230 ln = nd6_lookup(dst6, ND6_EXCLUSIVE, NULL);
1231 IF_AFDATA_RUNLOCK(ifp);
1232 if (ln == NULL)
1233 return;
1234
1235 if (ln->ln_state < ND6_LLINFO_REACHABLE)
1236 goto done;
1237
1238 /*
1239 * if we get upper-layer reachability confirmation many times,
1240 * it is possible we have false information.
1241 */
1242 if (!force) {
1243 ln->ln_byhint++;
1244 if (ln->ln_byhint > V_nd6_maxnudhint) {
1245 goto done;
1246 }
1247 }
1248
1249 ln->ln_state = ND6_LLINFO_REACHABLE;
1250 if (!ND6_LLINFO_PERMANENT(ln)) {
1251 nd6_llinfo_settimer_locked(ln,
1252 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
1253 }
1254 done:
1255 LLE_WUNLOCK(ln);
1256 }
1257
1258
1259 /*
1260 * Rejuvenate this function for routing operations related
1261 * processing.
1262 */
1263 void
1264 nd6_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
1265 {
1266 struct sockaddr_in6 *gateway;
1267 struct nd_defrouter *dr;
1268 struct ifnet *ifp;
1269
1270 RT_LOCK_ASSERT(rt);
1271 gateway = (struct sockaddr_in6 *)rt->rt_gateway;
1272 ifp = rt->rt_ifp;
1273
1274 switch (req) {
1275 case RTM_ADD:
1276 break;
1277
1278 case RTM_DELETE:
1279 if (!ifp)
1280 return;
1281 /*
1282 * Only indirect routes are interesting.
1283 */
1284 if ((rt->rt_flags & RTF_GATEWAY) == 0)
1285 return;
1286 /*
1287 * check for default route
1288 */
1289 if (IN6_ARE_ADDR_EQUAL(&in6addr_any,
1290 &SIN6(rt_key(rt))->sin6_addr)) {
1291 dr = defrouter_lookup(&gateway->sin6_addr, ifp);
1292 if (dr != NULL) {
1293 dr->installed = 0;
1294 defrouter_rele(dr);
1295 }
1296 }
1297 break;
1298 }
1299 }
1300
1301
1302 int
1303 nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
1304 {
1305 struct in6_ndireq *ndi = (struct in6_ndireq *)data;
1306 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
1307 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
1308 int error = 0;
1309
1310 if (ifp->if_afdata[AF_INET6] == NULL)
1311 return (EPFNOSUPPORT);
1312 switch (cmd) {
1313 case OSIOCGIFINFO_IN6:
1314 #define ND ndi->ndi
1315 /* XXX: old ndp(8) assumes a positive value for linkmtu. */
1316 bzero(&ND, sizeof(ND));
1317 ND.linkmtu = IN6_LINKMTU(ifp);
1318 ND.maxmtu = ND_IFINFO(ifp)->maxmtu;
1319 ND.basereachable = ND_IFINFO(ifp)->basereachable;
1320 ND.reachable = ND_IFINFO(ifp)->reachable;
1321 ND.retrans = ND_IFINFO(ifp)->retrans;
1322 ND.flags = ND_IFINFO(ifp)->flags;
1323 ND.recalctm = ND_IFINFO(ifp)->recalctm;
1324 ND.chlim = ND_IFINFO(ifp)->chlim;
1325 break;
1326 case SIOCGIFINFO_IN6:
1327 ND = *ND_IFINFO(ifp);
1328 break;
1329 case SIOCSIFINFO_IN6:
1330 /*
1331 * used to change host variables from userland.
1332 * intented for a use on router to reflect RA configurations.
1333 */
1334 /* 0 means 'unspecified' */
1335 if (ND.linkmtu != 0) {
1336 if (ND.linkmtu < IPV6_MMTU ||
1337 ND.linkmtu > IN6_LINKMTU(ifp)) {
1338 error = EINVAL;
1339 break;
1340 }
1341 ND_IFINFO(ifp)->linkmtu = ND.linkmtu;
1342 }
1343
1344 if (ND.basereachable != 0) {
1345 int obasereachable = ND_IFINFO(ifp)->basereachable;
1346
1347 ND_IFINFO(ifp)->basereachable = ND.basereachable;
1348 if (ND.basereachable != obasereachable)
1349 ND_IFINFO(ifp)->reachable =
1350 ND_COMPUTE_RTIME(ND.basereachable);
1351 }
1352 if (ND.retrans != 0)
1353 ND_IFINFO(ifp)->retrans = ND.retrans;
1354 if (ND.chlim != 0)
1355 ND_IFINFO(ifp)->chlim = ND.chlim;
1356 /* FALLTHROUGH */
1357 case SIOCSIFINFO_FLAGS:
1358 {
1359 struct ifaddr *ifa;
1360 struct in6_ifaddr *ia;
1361
1362 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
1363 !(ND.flags & ND6_IFF_IFDISABLED)) {
1364 /* ifdisabled 1->0 transision */
1365
1366 /*
1367 * If the interface is marked as ND6_IFF_IFDISABLED and
1368 * has an link-local address with IN6_IFF_DUPLICATED,
1369 * do not clear ND6_IFF_IFDISABLED.
1370 * See RFC 4862, Section 5.4.5.
1371 */
1372 IF_ADDR_RLOCK(ifp);
1373 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1374 if (ifa->ifa_addr->sa_family != AF_INET6)
1375 continue;
1376 ia = (struct in6_ifaddr *)ifa;
1377 if ((ia->ia6_flags & IN6_IFF_DUPLICATED) &&
1378 IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia)))
1379 break;
1380 }
1381 IF_ADDR_RUNLOCK(ifp);
1382
1383 if (ifa != NULL) {
1384 /* LLA is duplicated. */
1385 ND.flags |= ND6_IFF_IFDISABLED;
1386 log(LOG_ERR, "Cannot enable an interface"
1387 " with a link-local address marked"
1388 " duplicate.\n");
1389 } else {
1390 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IFDISABLED;
1391 if (ifp->if_flags & IFF_UP)
1392 in6_if_up(ifp);
1393 }
1394 } else if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) &&
1395 (ND.flags & ND6_IFF_IFDISABLED)) {
1396 /* ifdisabled 0->1 transision */
1397 /* Mark all IPv6 address as tentative. */
1398
1399 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1400 if (V_ip6_dad_count > 0 &&
1401 (ND_IFINFO(ifp)->flags & ND6_IFF_NO_DAD) == 0) {
1402 IF_ADDR_RLOCK(ifp);
1403 TAILQ_FOREACH(ifa, &ifp->if_addrhead,
1404 ifa_link) {
1405 if (ifa->ifa_addr->sa_family !=
1406 AF_INET6)
1407 continue;
1408 ia = (struct in6_ifaddr *)ifa;
1409 ia->ia6_flags |= IN6_IFF_TENTATIVE;
1410 }
1411 IF_ADDR_RUNLOCK(ifp);
1412 }
1413 }
1414
1415 if (ND.flags & ND6_IFF_AUTO_LINKLOCAL) {
1416 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL)) {
1417 /* auto_linklocal 0->1 transision */
1418
1419 /* If no link-local address on ifp, configure */
1420 ND_IFINFO(ifp)->flags |= ND6_IFF_AUTO_LINKLOCAL;
1421 in6_ifattach(ifp, NULL);
1422 } else if (!(ND.flags & ND6_IFF_IFDISABLED) &&
1423 ifp->if_flags & IFF_UP) {
1424 /*
1425 * When the IF already has
1426 * ND6_IFF_AUTO_LINKLOCAL, no link-local
1427 * address is assigned, and IFF_UP, try to
1428 * assign one.
1429 */
1430 IF_ADDR_RLOCK(ifp);
1431 TAILQ_FOREACH(ifa, &ifp->if_addrhead,
1432 ifa_link) {
1433 if (ifa->ifa_addr->sa_family !=
1434 AF_INET6)
1435 continue;
1436 ia = (struct in6_ifaddr *)ifa;
1437 if (IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia)))
1438 break;
1439 }
1440 IF_ADDR_RUNLOCK(ifp);
1441 if (ifa != NULL)
1442 /* No LLA is configured. */
1443 in6_ifattach(ifp, NULL);
1444 }
1445 }
1446 }
1447 ND_IFINFO(ifp)->flags = ND.flags;
1448 break;
1449 #undef ND
1450 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */
1451 /* sync kernel routing table with the default router list */
1452 defrouter_reset();
1453 defrouter_select();
1454 break;
1455 case SIOCSPFXFLUSH_IN6:
1456 {
1457 /* flush all the prefix advertised by routers */
1458 struct nd_prefix *pr, *next;
1459
1460 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) {
1461 struct in6_ifaddr *ia, *ia_next;
1462
1463 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1464 continue; /* XXX */
1465
1466 /* do we really have to remove addresses as well? */
1467 /* XXXRW: in6_ifaddrhead locking. */
1468 TAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link,
1469 ia_next) {
1470 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1471 continue;
1472
1473 if (ia->ia6_ndpr == pr)
1474 in6_purgeaddr(&ia->ia_ifa);
1475 }
1476 prelist_remove(pr);
1477 }
1478 break;
1479 }
1480 case SIOCSRTRFLUSH_IN6:
1481 {
1482 /* flush all the default routers */
1483 struct nd_drhead drq;
1484 struct nd_defrouter *dr;
1485
1486 TAILQ_INIT(&drq);
1487
1488 defrouter_reset();
1489
1490 ND6_WLOCK();
1491 while ((dr = TAILQ_FIRST(&V_nd_defrouter)) != NULL)
1492 defrouter_unlink(dr, &drq);
1493 ND6_WUNLOCK();
1494 while ((dr = TAILQ_FIRST(&drq)) != NULL) {
1495 TAILQ_REMOVE(&drq, dr, dr_entry);
1496 defrouter_del(dr);
1497 }
1498
1499 defrouter_select();
1500 break;
1501 }
1502 case SIOCGNBRINFO_IN6:
1503 {
1504 struct llentry *ln;
1505 struct in6_addr nb_addr = nbi->addr; /* make local for safety */
1506
1507 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0)
1508 return (error);
1509
1510 IF_AFDATA_RLOCK(ifp);
1511 ln = nd6_lookup(&nb_addr, 0, ifp);
1512 IF_AFDATA_RUNLOCK(ifp);
1513
1514 if (ln == NULL) {
1515 error = EINVAL;
1516 break;
1517 }
1518 nbi->state = ln->ln_state;
1519 nbi->asked = ln->la_asked;
1520 nbi->isrouter = ln->ln_router;
1521 if (ln->la_expire == 0)
1522 nbi->expire = 0;
1523 else
1524 nbi->expire = ln->la_expire +
1525 (time_second - time_uptime);
1526 LLE_RUNLOCK(ln);
1527 break;
1528 }
1529 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1530 ndif->ifindex = V_nd6_defifindex;
1531 break;
1532 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1533 return (nd6_setdefaultiface(ndif->ifindex));
1534 }
1535 return (error);
1536 }
1537
1538 /*
1539 * Create neighbor cache entry and cache link-layer address,
1540 * on reception of inbound ND6 packets. (RS/RA/NS/redirect)
1541 *
1542 * type - ICMP6 type
1543 * code - type dependent information
1544 *
1545 * XXXXX
1546 * The caller of this function already acquired the ndp
1547 * cache table lock because the cache entry is returned.
1548 */
1549 struct llentry *
1550 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr,
1551 int lladdrlen, int type, int code)
1552 {
1553 struct llentry *ln = NULL;
1554 int is_newentry;
1555 int do_update;
1556 int olladdr;
1557 int llchange;
1558 int flags;
1559 int newstate = 0;
1560 uint16_t router = 0;
1561 struct sockaddr_in6 sin6;
1562 struct mbuf *chain = NULL;
1563 int static_route = 0;
1564
1565 IF_AFDATA_UNLOCK_ASSERT(ifp);
1566
1567 KASSERT(ifp != NULL, ("%s: ifp == NULL", __func__));
1568 KASSERT(from != NULL, ("%s: from == NULL", __func__));
1569
1570 /* nothing must be updated for unspecified address */
1571 if (IN6_IS_ADDR_UNSPECIFIED(from))
1572 return NULL;
1573
1574 /*
1575 * Validation about ifp->if_addrlen and lladdrlen must be done in
1576 * the caller.
1577 *
1578 * XXX If the link does not have link-layer adderss, what should
1579 * we do? (ifp->if_addrlen == 0)
1580 * Spec says nothing in sections for RA, RS and NA. There's small
1581 * description on it in NS section (RFC 2461 7.2.3).
1582 */
1583 flags = lladdr ? ND6_EXCLUSIVE : 0;
1584 IF_AFDATA_RLOCK(ifp);
1585 ln = nd6_lookup(from, flags, ifp);
1586 IF_AFDATA_RUNLOCK(ifp);
1587 if (ln == NULL) {
1588 flags |= ND6_EXCLUSIVE;
1589 IF_AFDATA_LOCK(ifp);
1590 ln = nd6_lookup(from, flags | ND6_CREATE, ifp);
1591 IF_AFDATA_UNLOCK(ifp);
1592 is_newentry = 1;
1593 } else {
1594 /* do nothing if static ndp is set */
1595 if (ln->la_flags & LLE_STATIC) {
1596 static_route = 1;
1597 goto done;
1598 }
1599 is_newentry = 0;
1600 }
1601 if (ln == NULL)
1602 return (NULL);
1603
1604 olladdr = (ln->la_flags & LLE_VALID) ? 1 : 0;
1605 if (olladdr && lladdr) {
1606 llchange = bcmp(lladdr, &ln->ll_addr,
1607 ifp->if_addrlen);
1608 } else
1609 llchange = 0;
1610
1611 /*
1612 * newentry olladdr lladdr llchange (*=record)
1613 * 0 n n -- (1)
1614 * 0 y n -- (2)
1615 * 0 n y -- (3) * STALE
1616 * 0 y y n (4) *
1617 * 0 y y y (5) * STALE
1618 * 1 -- n -- (6) NOSTATE(= PASSIVE)
1619 * 1 -- y -- (7) * STALE
1620 */
1621
1622 if (lladdr) { /* (3-5) and (7) */
1623 /*
1624 * Record source link-layer address
1625 * XXX is it dependent to ifp->if_type?
1626 */
1627 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
1628 ln->la_flags |= LLE_VALID;
1629 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED);
1630 }
1631
1632 if (!is_newentry) {
1633 if ((!olladdr && lladdr != NULL) || /* (3) */
1634 (olladdr && lladdr != NULL && llchange)) { /* (5) */
1635 do_update = 1;
1636 newstate = ND6_LLINFO_STALE;
1637 } else /* (1-2,4) */
1638 do_update = 0;
1639 } else {
1640 do_update = 1;
1641 if (lladdr == NULL) /* (6) */
1642 newstate = ND6_LLINFO_NOSTATE;
1643 else /* (7) */
1644 newstate = ND6_LLINFO_STALE;
1645 }
1646
1647 if (do_update) {
1648 /*
1649 * Update the state of the neighbor cache.
1650 */
1651 ln->ln_state = newstate;
1652
1653 if (ln->ln_state == ND6_LLINFO_STALE) {
1654 if (ln->la_hold != NULL)
1655 nd6_grab_holdchain(ln, &chain, &sin6);
1656 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
1657 /* probe right away */
1658 nd6_llinfo_settimer_locked((void *)ln, 0);
1659 }
1660 }
1661
1662 /*
1663 * ICMP6 type dependent behavior.
1664 *
1665 * NS: clear IsRouter if new entry
1666 * RS: clear IsRouter
1667 * RA: set IsRouter if there's lladdr
1668 * redir: clear IsRouter if new entry
1669 *
1670 * RA case, (1):
1671 * The spec says that we must set IsRouter in the following cases:
1672 * - If lladdr exist, set IsRouter. This means (1-5).
1673 * - If it is old entry (!newentry), set IsRouter. This means (7).
1674 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1675 * A quetion arises for (1) case. (1) case has no lladdr in the
1676 * neighbor cache, this is similar to (6).
1677 * This case is rare but we figured that we MUST NOT set IsRouter.
1678 *
1679 * newentry olladdr lladdr llchange NS RS RA redir
1680 * D R
1681 * 0 n n -- (1) c ? s
1682 * 0 y n -- (2) c s s
1683 * 0 n y -- (3) c s s
1684 * 0 y y n (4) c s s
1685 * 0 y y y (5) c s s
1686 * 1 -- n -- (6) c c c s
1687 * 1 -- y -- (7) c c s c s
1688 *
1689 * (c=clear s=set)
1690 */
1691 switch (type & 0xff) {
1692 case ND_NEIGHBOR_SOLICIT:
1693 /*
1694 * New entry must have is_router flag cleared.
1695 */
1696 if (is_newentry) /* (6-7) */
1697 ln->ln_router = 0;
1698 break;
1699 case ND_REDIRECT:
1700 /*
1701 * If the icmp is a redirect to a better router, always set the
1702 * is_router flag. Otherwise, if the entry is newly created,
1703 * clear the flag. [RFC 2461, sec 8.3]
1704 */
1705 if (code == ND_REDIRECT_ROUTER)
1706 ln->ln_router = 1;
1707 else if (is_newentry) /* (6-7) */
1708 ln->ln_router = 0;
1709 break;
1710 case ND_ROUTER_SOLICIT:
1711 /*
1712 * is_router flag must always be cleared.
1713 */
1714 ln->ln_router = 0;
1715 break;
1716 case ND_ROUTER_ADVERT:
1717 /*
1718 * Mark an entry with lladdr as a router.
1719 */
1720 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */
1721 (is_newentry && lladdr)) { /* (7) */
1722 ln->ln_router = 1;
1723 }
1724 break;
1725 }
1726
1727 if (ln != NULL) {
1728 static_route = (ln->la_flags & LLE_STATIC);
1729 router = ln->ln_router;
1730
1731 if (flags & ND6_EXCLUSIVE)
1732 LLE_WUNLOCK(ln);
1733 else
1734 LLE_RUNLOCK(ln);
1735 if (static_route)
1736 ln = NULL;
1737 }
1738 if (chain != NULL)
1739 nd6_flush_holdchain(ifp, ifp, chain, &sin6);
1740
1741 /*
1742 * When the link-layer address of a router changes, select the
1743 * best router again. In particular, when the neighbor entry is newly
1744 * created, it might affect the selection policy.
1745 * Question: can we restrict the first condition to the "is_newentry"
1746 * case?
1747 * XXX: when we hear an RA from a new router with the link-layer
1748 * address option, defrouter_select() is called twice, since
1749 * defrtrlist_update called the function as well. However, I believe
1750 * we can compromise the overhead, since it only happens the first
1751 * time.
1752 * XXX: although defrouter_select() should not have a bad effect
1753 * for those are not autoconfigured hosts, we explicitly avoid such
1754 * cases for safety.
1755 */
1756 if (do_update && router &&
1757 ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) {
1758 /*
1759 * guaranteed recursion
1760 */
1761 defrouter_select();
1762 }
1763
1764 return (ln);
1765 done:
1766 if (ln != NULL) {
1767 if (flags & ND6_EXCLUSIVE)
1768 LLE_WUNLOCK(ln);
1769 else
1770 LLE_RUNLOCK(ln);
1771 if (static_route)
1772 ln = NULL;
1773 }
1774 return (ln);
1775 }
1776
1777 static void
1778 nd6_slowtimo(void *arg)
1779 {
1780 CURVNET_SET((struct vnet *) arg);
1781 struct nd_ifinfo *nd6if;
1782 struct ifnet *ifp;
1783
1784 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
1785 nd6_slowtimo, curvnet);
1786 IFNET_RLOCK_NOSLEEP();
1787 TAILQ_FOREACH(ifp, &V_ifnet, if_list) {
1788 if (ifp->if_afdata[AF_INET6] == NULL)
1789 continue;
1790 nd6if = ND_IFINFO(ifp);
1791 if (nd6if->basereachable && /* already initialized */
1792 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
1793 /*
1794 * Since reachable time rarely changes by router
1795 * advertisements, we SHOULD insure that a new random
1796 * value gets recomputed at least once every few hours.
1797 * (RFC 2461, 6.3.4)
1798 */
1799 nd6if->recalctm = V_nd6_recalc_reachtm_interval;
1800 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
1801 }
1802 }
1803 IFNET_RUNLOCK_NOSLEEP();
1804 CURVNET_RESTORE();
1805 }
1806
1807 void
1808 nd6_grab_holdchain(struct llentry *ln, struct mbuf **chain,
1809 struct sockaddr_in6 *sin6)
1810 {
1811
1812 LLE_WLOCK_ASSERT(ln);
1813
1814 *chain = ln->la_hold;
1815 ln->la_hold = NULL;
1816 memcpy(sin6, L3_ADDR_SIN6(ln), sizeof(*sin6));
1817
1818 if (ln->ln_state == ND6_LLINFO_STALE) {
1819
1820 /*
1821 * The first time we send a packet to a
1822 * neighbor whose entry is STALE, we have
1823 * to change the state to DELAY and a sets
1824 * a timer to expire in DELAY_FIRST_PROBE_TIME
1825 * seconds to ensure do neighbor unreachability
1826 * detection on expiration.
1827 * (RFC 2461 7.3.3)
1828 */
1829 ln->la_asked = 0;
1830 ln->ln_state = ND6_LLINFO_DELAY;
1831 nd6_llinfo_settimer_locked(ln, (long)V_nd6_delay * hz);
1832 }
1833 }
1834
1835 static int
1836 nd6_output_ifp(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1837 struct sockaddr_in6 *dst)
1838 {
1839 int error;
1840 int ip6len;
1841 struct ip6_hdr *ip6;
1842 struct m_tag *mtag;
1843
1844 #ifdef MAC
1845 mac_netinet6_nd6_send(ifp, m);
1846 #endif
1847
1848 /*
1849 * If called from nd6_ns_output() (NS), nd6_na_output() (NA),
1850 * icmp6_redirect_output() (REDIRECT) or from rip6_output() (RS, RA
1851 * as handled by rtsol and rtadvd), mbufs will be tagged for SeND
1852 * to be diverted to user space. When re-injected into the kernel,
1853 * send_output() will directly dispatch them to the outgoing interface.
1854 */
1855 if (send_sendso_input_hook != NULL) {
1856 mtag = m_tag_find(m, PACKET_TAG_ND_OUTGOING, NULL);
1857 if (mtag != NULL) {
1858 ip6 = mtod(m, struct ip6_hdr *);
1859 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
1860 /* Use the SEND socket */
1861 error = send_sendso_input_hook(m, ifp, SND_OUT,
1862 ip6len);
1863 /* -1 == no app on SEND socket */
1864 if (error == 0 || error != -1)
1865 return (error);
1866 }
1867 }
1868
1869 m_clrprotoflags(m); /* Avoid confusing lower layers. */
1870 IP_PROBE(send, NULL, NULL, mtod(m, struct ip6_hdr *), ifp, NULL,
1871 mtod(m, struct ip6_hdr *));
1872
1873 if ((ifp->if_flags & IFF_LOOPBACK) == 0)
1874 origifp = ifp;
1875
1876 error = (*ifp->if_output)(origifp, m, (struct sockaddr *)dst, NULL);
1877 return (error);
1878 }
1879
1880 /*
1881 * IPv6 packet output - light version.
1882 * Checks if destination LLE exists and is in proper state
1883 * (e.g no modification required). If not true, fall back to
1884 * "heavy" version.
1885 */
1886 int
1887 nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1888 struct sockaddr_in6 *dst, struct rtentry *rt0)
1889 {
1890 struct llentry *ln = NULL;
1891
1892 /* discard the packet if IPv6 operation is disabled on the interface */
1893 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) {
1894 m_freem(m);
1895 return (ENETDOWN); /* better error? */
1896 }
1897
1898 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1899 goto sendpkt;
1900
1901 if (nd6_need_cache(ifp) == 0)
1902 goto sendpkt;
1903
1904 IF_AFDATA_RLOCK(ifp);
1905 ln = nd6_lookup(&dst->sin6_addr, 0, ifp);
1906 IF_AFDATA_RUNLOCK(ifp);
1907
1908 /*
1909 * Perform fast path for the following cases:
1910 * 1) lle state is REACHABLE
1911 * 2) lle state is DELAY (NS message sentNS message sent)
1912 *
1913 * Every other case involves lle modification, so we handle
1914 * them separately.
1915 */
1916 if (ln == NULL || (ln->ln_state != ND6_LLINFO_REACHABLE &&
1917 ln->ln_state != ND6_LLINFO_DELAY)) {
1918 /* Fall back to slow processing path */
1919 if (ln != NULL)
1920 LLE_RUNLOCK(ln);
1921 return (nd6_output_lle(ifp, origifp, m, dst));
1922 }
1923
1924 sendpkt:
1925 if (ln != NULL)
1926 LLE_RUNLOCK(ln);
1927
1928 return (nd6_output_ifp(ifp, origifp, m, dst));
1929 }
1930
1931
1932 /*
1933 * Output IPv6 packet - heavy version.
1934 * Function assume that either
1935 * 1) destination LLE does not exist, is invalid or stale, so
1936 * ND6_EXCLUSIVE lock needs to be acquired
1937 * 2) destination lle is provided (with ND6_EXCLUSIVE lock),
1938 * in that case packets are queued in &chain.
1939 *
1940 */
1941 static int
1942 nd6_output_lle(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1943 struct sockaddr_in6 *dst)
1944 {
1945 struct llentry *lle = NULL;
1946 int flags = 0;
1947
1948 KASSERT(m != NULL, ("NULL mbuf, nothing to send"));
1949 /* discard the packet if IPv6 operation is disabled on the interface */
1950 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) {
1951 m_freem(m);
1952 return (ENETDOWN); /* better error? */
1953 }
1954
1955 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1956 goto sendpkt;
1957
1958 if (nd6_need_cache(ifp) == 0)
1959 goto sendpkt;
1960
1961 /*
1962 * Address resolution or Neighbor Unreachability Detection
1963 * for the next hop.
1964 * At this point, the destination of the packet must be a unicast
1965 * or an anycast address(i.e. not a multicast).
1966 */
1967 if (lle == NULL) {
1968 IF_AFDATA_RLOCK(ifp);
1969 lle = nd6_lookup(&dst->sin6_addr, ND6_EXCLUSIVE, ifp);
1970 IF_AFDATA_RUNLOCK(ifp);
1971 if ((lle == NULL) && nd6_is_addr_neighbor(dst, ifp)) {
1972 /*
1973 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
1974 * the condition below is not very efficient. But we believe
1975 * it is tolerable, because this should be a rare case.
1976 */
1977 flags = ND6_CREATE | ND6_EXCLUSIVE;
1978 IF_AFDATA_LOCK(ifp);
1979 lle = nd6_lookup(&dst->sin6_addr, flags, ifp);
1980 IF_AFDATA_UNLOCK(ifp);
1981 }
1982 }
1983 if (lle == NULL) {
1984 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 &&
1985 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) {
1986 char ip6buf[INET6_ADDRSTRLEN];
1987 log(LOG_DEBUG,
1988 "nd6_output: can't allocate llinfo for %s "
1989 "(ln=%p)\n",
1990 ip6_sprintf(ip6buf, &dst->sin6_addr), lle);
1991 m_freem(m);
1992 return (ENOBUFS);
1993 }
1994 goto sendpkt; /* send anyway */
1995 }
1996
1997 LLE_WLOCK_ASSERT(lle);
1998
1999 /* We don't have to do link-layer address resolution on a p2p link. */
2000 if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
2001 lle->ln_state < ND6_LLINFO_REACHABLE) {
2002 lle->ln_state = ND6_LLINFO_STALE;
2003 nd6_llinfo_settimer_locked(lle, (long)V_nd6_gctimer * hz);
2004 }
2005
2006 /*
2007 * The first time we send a packet to a neighbor whose entry is
2008 * STALE, we have to change the state to DELAY and a sets a timer to
2009 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
2010 * neighbor unreachability detection on expiration.
2011 * (RFC 2461 7.3.3)
2012 */
2013 if (lle->ln_state == ND6_LLINFO_STALE) {
2014 lle->la_asked = 0;
2015 lle->ln_state = ND6_LLINFO_DELAY;
2016 nd6_llinfo_settimer_locked(lle, (long)V_nd6_delay * hz);
2017 }
2018
2019 /*
2020 * If the neighbor cache entry has a state other than INCOMPLETE
2021 * (i.e. its link-layer address is already resolved), just
2022 * send the packet.
2023 */
2024 if (lle->ln_state > ND6_LLINFO_INCOMPLETE)
2025 goto sendpkt;
2026
2027 /*
2028 * There is a neighbor cache entry, but no ethernet address
2029 * response yet. Append this latest packet to the end of the
2030 * packet queue in the mbuf, unless the number of the packet
2031 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen,
2032 * the oldest packet in the queue will be removed.
2033 */
2034 if (lle->ln_state == ND6_LLINFO_NOSTATE)
2035 lle->ln_state = ND6_LLINFO_INCOMPLETE;
2036
2037 if (lle->la_hold != NULL) {
2038 struct mbuf *m_hold;
2039 int i;
2040
2041 i = 0;
2042 for (m_hold = lle->la_hold; m_hold; m_hold = m_hold->m_nextpkt){
2043 i++;
2044 if (m_hold->m_nextpkt == NULL) {
2045 m_hold->m_nextpkt = m;
2046 break;
2047 }
2048 }
2049 while (i >= V_nd6_maxqueuelen) {
2050 m_hold = lle->la_hold;
2051 lle->la_hold = lle->la_hold->m_nextpkt;
2052 m_freem(m_hold);
2053 i--;
2054 }
2055 } else {
2056 lle->la_hold = m;
2057 }
2058
2059 /*
2060 * If there has been no NS for the neighbor after entering the
2061 * INCOMPLETE state, send the first solicitation.
2062 */
2063 if (!ND6_LLINFO_PERMANENT(lle) && lle->la_asked == 0) {
2064 lle->la_asked++;
2065
2066 nd6_llinfo_settimer_locked(lle,
2067 (long)ND_IFINFO(ifp)->retrans * hz / 1000);
2068 LLE_WUNLOCK(lle);
2069 nd6_ns_output(ifp, NULL, &dst->sin6_addr, lle, NULL);
2070 } else {
2071 /* We did the lookup so we need to do the unlock here. */
2072 LLE_WUNLOCK(lle);
2073 }
2074
2075 return (0);
2076
2077 sendpkt:
2078 if (lle != NULL)
2079 LLE_WUNLOCK(lle);
2080
2081 return (nd6_output_ifp(ifp, origifp, m, dst));
2082 }
2083
2084
2085 int
2086 nd6_flush_holdchain(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *chain,
2087 struct sockaddr_in6 *dst)
2088 {
2089 struct mbuf *m, *m_head;
2090 struct ifnet *outifp;
2091 int error = 0;
2092
2093 m_head = chain;
2094 if ((ifp->if_flags & IFF_LOOPBACK) != 0)
2095 outifp = origifp;
2096 else
2097 outifp = ifp;
2098
2099 while (m_head) {
2100 m = m_head;
2101 m_head = m_head->m_nextpkt;
2102 error = nd6_output_ifp(ifp, origifp, m, dst);
2103 }
2104
2105 /*
2106 * XXX
2107 * note that intermediate errors are blindly ignored - but this is
2108 * the same convention as used with nd6_output when called by
2109 * nd6_cache_lladdr
2110 */
2111 return (error);
2112 }
2113
2114
2115 int
2116 nd6_need_cache(struct ifnet *ifp)
2117 {
2118 /*
2119 * XXX: we currently do not make neighbor cache on any interface
2120 * other than ARCnet, Ethernet, FDDI and GIF.
2121 *
2122 * RFC2893 says:
2123 * - unidirectional tunnels needs no ND
2124 */
2125 switch (ifp->if_type) {
2126 case IFT_ARCNET:
2127 case IFT_ETHER:
2128 case IFT_FDDI:
2129 case IFT_IEEE1394:
2130 #ifdef IFT_L2VLAN
2131 case IFT_L2VLAN:
2132 #endif
2133 #ifdef IFT_IEEE80211
2134 case IFT_IEEE80211:
2135 #endif
2136 case IFT_INFINIBAND:
2137 case IFT_BRIDGE:
2138 case IFT_PROPVIRTUAL:
2139 return (1);
2140 default:
2141 return (0);
2142 }
2143 }
2144
2145 /*
2146 * the callers of this function need to be re-worked to drop
2147 * the lle lock, drop here for now
2148 */
2149 int
2150 nd6_storelladdr(struct ifnet *ifp, struct mbuf *m,
2151 const struct sockaddr *dst, u_char *desten, struct llentry **lle)
2152 {
2153 struct llentry *ln;
2154
2155 *lle = NULL;
2156 IF_AFDATA_UNLOCK_ASSERT(ifp);
2157 if (m != NULL && m->m_flags & M_MCAST) {
2158 int i;
2159
2160 switch (ifp->if_type) {
2161 case IFT_ETHER:
2162 case IFT_FDDI:
2163 #ifdef IFT_L2VLAN
2164 case IFT_L2VLAN:
2165 #endif
2166 #ifdef IFT_IEEE80211
2167 case IFT_IEEE80211:
2168 #endif
2169 case IFT_BRIDGE:
2170 case IFT_ISO88025:
2171 ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr,
2172 desten);
2173 return (0);
2174 case IFT_IEEE1394:
2175 /*
2176 * netbsd can use if_broadcastaddr, but we don't do so
2177 * to reduce # of ifdef.
2178 */
2179 for (i = 0; i < ifp->if_addrlen; i++)
2180 desten[i] = ~0;
2181 return (0);
2182 case IFT_ARCNET:
2183 *desten = 0;
2184 return (0);
2185 default:
2186 m_freem(m);
2187 return (EAFNOSUPPORT);
2188 }
2189 }
2190
2191
2192 /*
2193 * the entry should have been created in nd6_store_lladdr
2194 */
2195 IF_AFDATA_RLOCK(ifp);
2196 ln = lla_lookup(LLTABLE6(ifp), 0, dst);
2197 IF_AFDATA_RUNLOCK(ifp);
2198 if ((ln == NULL) || !(ln->la_flags & LLE_VALID)) {
2199 if (ln != NULL)
2200 LLE_RUNLOCK(ln);
2201 /* this could happen, if we could not allocate memory */
2202 m_freem(m);
2203 return (1);
2204 }
2205
2206 bcopy(&ln->ll_addr, desten, ifp->if_addrlen);
2207 *lle = ln;
2208 LLE_RUNLOCK(ln);
2209 /*
2210 * A *small* use after free race exists here
2211 */
2212 return (0);
2213 }
2214
2215 static void
2216 clear_llinfo_pqueue(struct llentry *ln)
2217 {
2218 struct mbuf *m_hold, *m_hold_next;
2219
2220 for (m_hold = ln->la_hold; m_hold; m_hold = m_hold_next) {
2221 m_hold_next = m_hold->m_nextpkt;
2222 m_freem(m_hold);
2223 }
2224
2225 ln->la_hold = NULL;
2226 }
2227
2228 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
2229 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
2230 #ifdef SYSCTL_DECL
2231 SYSCTL_DECL(_net_inet6_icmp6);
2232 #endif
2233 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2234 CTLFLAG_RD, nd6_sysctl_drlist, "");
2235 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
2236 CTLFLAG_RD, nd6_sysctl_prlist, "");
2237 SYSCTL_VNET_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen,
2238 CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, "");
2239 SYSCTL_VNET_INT(_net_inet6_icmp6, OID_AUTO, nd6_gctimer,
2240 CTLFLAG_RW, &VNET_NAME(nd6_gctimer), (60 * 60 * 24), "");
2241
2242 static int
2243 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2244 {
2245 struct in6_defrouter d;
2246 struct nd_defrouter *dr;
2247 int error;
2248
2249 if (req->newptr != NULL)
2250 return (EPERM);
2251
2252 error = sysctl_wire_old_buffer(req, 0);
2253 if (error != 0)
2254 return (error);
2255
2256 bzero(&d, sizeof(d));
2257 d.rtaddr.sin6_family = AF_INET6;
2258 d.rtaddr.sin6_len = sizeof(d.rtaddr);
2259
2260 ND6_RLOCK();
2261 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
2262 d.rtaddr.sin6_addr = dr->rtaddr;
2263 error = sa6_recoverscope(&d.rtaddr);
2264 if (error != 0)
2265 break;
2266 d.flags = dr->raflags;
2267 d.rtlifetime = dr->rtlifetime;
2268 d.expire = dr->expire + (time_second - time_uptime);
2269 d.if_index = dr->ifp->if_index;
2270 error = SYSCTL_OUT(req, &d, sizeof(d));
2271 if (error != 0)
2272 break;
2273 }
2274 ND6_RUNLOCK();
2275 return (error);
2276 }
2277
2278 static int
2279 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
2280 {
2281 struct in6_prefix p;
2282 struct sockaddr_in6 s6;
2283 struct nd_prefix *pr;
2284 struct nd_pfxrouter *pfr;
2285 time_t maxexpire;
2286 int error;
2287 char ip6buf[INET6_ADDRSTRLEN];
2288
2289 if (req->newptr)
2290 return (EPERM);
2291
2292 bzero(&p, sizeof(p));
2293 p.origin = PR_ORIG_RA;
2294 bzero(&s6, sizeof(s6));
2295 s6.sin6_family = AF_INET6;
2296 s6.sin6_len = sizeof(s6);
2297
2298 /*
2299 * XXX locking
2300 */
2301 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
2302 p.prefix = pr->ndpr_prefix;
2303 if (sa6_recoverscope(&p.prefix)) {
2304 log(LOG_ERR, "scope error in prefix list (%s)\n",
2305 ip6_sprintf(ip6buf, &p.prefix.sin6_addr));
2306 /* XXX: press on... */
2307 }
2308 p.raflags = pr->ndpr_raf;
2309 p.prefixlen = pr->ndpr_plen;
2310 p.vltime = pr->ndpr_vltime;
2311 p.pltime = pr->ndpr_pltime;
2312 p.if_index = pr->ndpr_ifp->if_index;
2313 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME)
2314 p.expire = 0;
2315 else {
2316 /* XXX: we assume time_t is signed. */
2317 maxexpire = (-1) &
2318 ~((time_t)1 << ((sizeof(maxexpire) * 8) - 1));
2319 if (pr->ndpr_vltime < maxexpire - pr->ndpr_lastupdate)
2320 p.expire = pr->ndpr_lastupdate +
2321 pr->ndpr_vltime +
2322 (time_second - time_uptime);
2323 else
2324 p.expire = maxexpire;
2325 }
2326 p.refcnt = pr->ndpr_refcnt;
2327 p.flags = pr->ndpr_stateflags;
2328 p.advrtrs = 0;
2329 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry)
2330 p.advrtrs++;
2331 error = SYSCTL_OUT(req, &p, sizeof(p));
2332 if (error != 0)
2333 return (error);
2334 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) {
2335 s6.sin6_addr = pfr->router->rtaddr;
2336 if (sa6_recoverscope(&s6))
2337 log(LOG_ERR,
2338 "scope error in prefix list (%s)\n",
2339 ip6_sprintf(ip6buf, &pfr->router->rtaddr));
2340 error = SYSCTL_OUT(req, &s6, sizeof(s6));
2341 if (error != 0)
2342 return (error);
2343 }
2344 }
2345 return (0);
2346 }
Cache object: 236724da96a4529dbebdb1783abf8c16
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