1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $KAME: nd6_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $
32 */
33
34 #include <sys/cdefs.h>
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/refcount.h>
43 #include <sys/socket.h>
44 #include <sys/sockio.h>
45 #include <sys/time.h>
46 #include <sys/kernel.h>
47 #include <sys/lock.h>
48 #include <sys/errno.h>
49 #include <sys/rmlock.h>
50 #include <sys/rwlock.h>
51 #include <sys/sysctl.h>
52 #include <sys/syslog.h>
53 #include <sys/queue.h>
54
55 #include <net/if.h>
56 #include <net/if_var.h>
57 #include <net/if_private.h>
58 #include <net/if_types.h>
59 #include <net/if_dl.h>
60 #include <net/route.h>
61 #include <net/route/nhop.h>
62 #include <net/route/route_ctl.h>
63 #include <net/radix.h>
64 #include <net/vnet.h>
65
66 #include <netinet/in.h>
67 #include <net/if_llatbl.h>
68 #include <netinet6/in6_var.h>
69 #include <netinet6/in6_ifattach.h>
70 #include <netinet/ip6.h>
71 #include <netinet6/ip6_var.h>
72 #include <netinet6/nd6.h>
73 #include <netinet/icmp6.h>
74 #include <netinet6/scope6_var.h>
75
76 static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *);
77 static int prelist_update(struct nd_prefixctl *, struct nd_defrouter *,
78 struct mbuf *, int);
79 static int nd6_prefix_onlink(struct nd_prefix *);
80
81 TAILQ_HEAD(nd6_drhead, nd_defrouter);
82 VNET_DEFINE_STATIC(struct nd6_drhead, nd6_defrouter);
83 #define V_nd6_defrouter VNET(nd6_defrouter)
84
85 VNET_DECLARE(int, nd6_recalc_reachtm_interval);
86 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval)
87
88 VNET_DEFINE_STATIC(struct ifnet *, nd6_defifp);
89 VNET_DEFINE(int, nd6_defifindex);
90 #define V_nd6_defifp VNET(nd6_defifp)
91
92 VNET_DEFINE(int, ip6_use_tempaddr) = 0;
93
94 VNET_DEFINE(int, ip6_desync_factor);
95 VNET_DEFINE(u_int32_t, ip6_temp_preferred_lifetime) = DEF_TEMP_PREFERRED_LIFETIME;
96 VNET_DEFINE(u_int32_t, ip6_temp_valid_lifetime) = DEF_TEMP_VALID_LIFETIME;
97
98 VNET_DEFINE(int, ip6_temp_regen_advance) = TEMPADDR_REGEN_ADVANCE;
99
100 #ifdef EXPERIMENTAL
101 VNET_DEFINE_STATIC(int, nd6_ignore_ipv6_only_ra) = 1;
102 #define V_nd6_ignore_ipv6_only_ra VNET(nd6_ignore_ipv6_only_ra)
103 SYSCTL_INT(_net_inet6_icmp6, OID_AUTO,
104 nd6_ignore_ipv6_only_ra, CTLFLAG_VNET | CTLFLAG_RW,
105 &VNET_NAME(nd6_ignore_ipv6_only_ra), 0,
106 "Ignore the 'IPv6-Only flag' in RA messages in compliance with "
107 "draft-ietf-6man-ipv6only-flag");
108 #endif
109
110 /* RTPREF_MEDIUM has to be 0! */
111 #define RTPREF_HIGH 1
112 #define RTPREF_MEDIUM 0
113 #define RTPREF_LOW (-1)
114 #define RTPREF_RESERVED (-2)
115 #define RTPREF_INVALID (-3) /* internal */
116
117 static void
defrouter_ref(struct nd_defrouter * dr)118 defrouter_ref(struct nd_defrouter *dr)
119 {
120
121 refcount_acquire(&dr->refcnt);
122 }
123
124 void
defrouter_rele(struct nd_defrouter * dr)125 defrouter_rele(struct nd_defrouter *dr)
126 {
127
128 if (refcount_release(&dr->refcnt))
129 free(dr, M_IP6NDP);
130 }
131
132 /*
133 * Remove a router from the global list and optionally stash it in a
134 * caller-supplied queue.
135 */
136 static void
defrouter_unlink(struct nd_defrouter * dr,struct nd6_drhead * drq)137 defrouter_unlink(struct nd_defrouter *dr, struct nd6_drhead *drq)
138 {
139
140 ND6_WLOCK_ASSERT();
141
142 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry);
143 V_nd6_list_genid++;
144 if (drq != NULL)
145 TAILQ_INSERT_TAIL(drq, dr, dr_entry);
146 }
147
148 /*
149 * Receive Router Solicitation Message - just for routers.
150 * Router solicitation/advertisement is mostly managed by userland program
151 * (rtadvd) so here we have no function like nd6_ra_output().
152 *
153 * Based on RFC 2461
154 */
155 void
nd6_rs_input(struct mbuf * m,int off,int icmp6len)156 nd6_rs_input(struct mbuf *m, int off, int icmp6len)
157 {
158 struct ifnet *ifp;
159 struct ip6_hdr *ip6;
160 struct nd_router_solicit *nd_rs;
161 struct in6_addr saddr6;
162 union nd_opts ndopts;
163 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
164 char *lladdr;
165 int lladdrlen;
166
167 ifp = m->m_pkthdr.rcvif;
168
169 /*
170 * Accept RS only when V_ip6_forwarding=1 and the interface has
171 * no ND6_IFF_ACCEPT_RTADV.
172 */
173 if (!V_ip6_forwarding || ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV)
174 goto freeit;
175
176 /* RFC 6980: Nodes MUST silently ignore fragments */
177 if(m->m_flags & M_FRAGMENTED)
178 goto freeit;
179
180 /* Sanity checks */
181 ip6 = mtod(m, struct ip6_hdr *);
182 if (__predict_false(ip6->ip6_hlim != 255)) {
183 ICMP6STAT_INC(icp6s_invlhlim);
184 nd6log((LOG_ERR,
185 "%s: invalid hlim (%d) from %s to %s on %s\n", __func__,
186 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
187 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
188 goto bad;
189 }
190
191 /*
192 * Don't update the neighbor cache, if src = ::.
193 * This indicates that the src has no IP address assigned yet.
194 */
195 saddr6 = ip6->ip6_src;
196 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
197 goto freeit;
198
199 if (m->m_len < off + icmp6len) {
200 m = m_pullup(m, off + icmp6len);
201 if (m == NULL) {
202 IP6STAT_INC(ip6s_exthdrtoolong);
203 return;
204 }
205 }
206 ip6 = mtod(m, struct ip6_hdr *);
207 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off);
208
209 icmp6len -= sizeof(*nd_rs);
210 nd6_option_init(nd_rs + 1, icmp6len, &ndopts);
211 if (nd6_options(&ndopts) < 0) {
212 nd6log((LOG_INFO,
213 "%s: invalid ND option, ignored\n", __func__));
214 /* nd6_options have incremented stats */
215 goto freeit;
216 }
217
218 lladdr = NULL;
219 lladdrlen = 0;
220 if (ndopts.nd_opts_src_lladdr) {
221 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
222 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
223 }
224
225 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
226 nd6log((LOG_INFO,
227 "%s: lladdrlen mismatch for %s (if %d, RS packet %d)\n",
228 __func__, ip6_sprintf(ip6bufs, &saddr6),
229 ifp->if_addrlen, lladdrlen - 2));
230 goto bad;
231 }
232
233 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0);
234
235 freeit:
236 m_freem(m);
237 return;
238
239 bad:
240 ICMP6STAT_INC(icp6s_badrs);
241 m_freem(m);
242 }
243
244 #ifdef EXPERIMENTAL
245 /*
246 * An initial update routine for draft-ietf-6man-ipv6only-flag.
247 * We need to iterate over all default routers for the given
248 * interface to see whether they are all advertising the "S"
249 * (IPv6-Only) flag. If they do set, otherwise unset, the
250 * interface flag we later use to filter on.
251 */
252 static void
defrtr_ipv6_only_ifp(struct ifnet * ifp)253 defrtr_ipv6_only_ifp(struct ifnet *ifp)
254 {
255 struct nd_defrouter *dr;
256 bool ipv6_only, ipv6_only_old;
257 #ifdef INET
258 struct epoch_tracker et;
259 struct ifaddr *ifa;
260 bool has_ipv4_addr;
261 #endif
262
263 if (V_nd6_ignore_ipv6_only_ra != 0)
264 return;
265
266 ipv6_only = true;
267 ND6_RLOCK();
268 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry)
269 if (dr->ifp == ifp &&
270 (dr->raflags & ND_RA_FLAG_IPV6_ONLY) == 0)
271 ipv6_only = false;
272 ND6_RUNLOCK();
273
274 IF_AFDATA_WLOCK(ifp);
275 ipv6_only_old = ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY;
276 IF_AFDATA_WUNLOCK(ifp);
277
278 /* If nothing changed, we have an early exit. */
279 if (ipv6_only == ipv6_only_old)
280 return;
281
282 #ifdef INET
283 /*
284 * Should we want to set the IPV6-ONLY flag, check if the
285 * interface has a non-0/0 and non-link-local IPv4 address
286 * configured on it. If it has we will assume working
287 * IPv4 operations and will clear the interface flag.
288 */
289 has_ipv4_addr = false;
290 if (ipv6_only) {
291 NET_EPOCH_ENTER(et);
292 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
293 if (ifa->ifa_addr->sa_family != AF_INET)
294 continue;
295 if (in_canforward(
296 satosin(ifa->ifa_addr)->sin_addr)) {
297 has_ipv4_addr = true;
298 break;
299 }
300 }
301 NET_EPOCH_EXIT(et);
302 }
303 if (ipv6_only && has_ipv4_addr) {
304 log(LOG_NOTICE, "%s rcvd RA w/ IPv6-Only flag set but has IPv4 "
305 "configured, ignoring IPv6-Only flag.\n", ifp->if_xname);
306 ipv6_only = false;
307 }
308 #endif
309
310 IF_AFDATA_WLOCK(ifp);
311 if (ipv6_only)
312 ND_IFINFO(ifp)->flags |= ND6_IFF_IPV6_ONLY;
313 else
314 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IPV6_ONLY;
315 IF_AFDATA_WUNLOCK(ifp);
316
317 #ifdef notyet
318 /* Send notification of flag change. */
319 #endif
320 }
321
322 static void
defrtr_ipv6_only_ipf_down(struct ifnet * ifp)323 defrtr_ipv6_only_ipf_down(struct ifnet *ifp)
324 {
325
326 IF_AFDATA_WLOCK(ifp);
327 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IPV6_ONLY;
328 IF_AFDATA_WUNLOCK(ifp);
329 }
330 #endif /* EXPERIMENTAL */
331
332 void
nd6_ifnet_link_event(void * arg __unused,struct ifnet * ifp,int linkstate)333 nd6_ifnet_link_event(void *arg __unused, struct ifnet *ifp, int linkstate)
334 {
335
336 /*
337 * XXX-BZ we might want to trigger re-evaluation of our default router
338 * availability. E.g., on link down the default router might be
339 * unreachable but a different interface might still have connectivity.
340 */
341
342 #ifdef EXPERIMENTAL
343 if (linkstate == LINK_STATE_DOWN)
344 defrtr_ipv6_only_ipf_down(ifp);
345 #endif
346 }
347
348 /*
349 * Receive Router Advertisement Message.
350 *
351 * Based on RFC 2461
352 * TODO: on-link bit on prefix information
353 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing
354 */
355 void
nd6_ra_input(struct mbuf * m,int off,int icmp6len)356 nd6_ra_input(struct mbuf *m, int off, int icmp6len)
357 {
358 struct ifnet *ifp;
359 struct nd_ifinfo *ndi;
360 struct ip6_hdr *ip6;
361 struct nd_router_advert *nd_ra;
362 struct in6_addr saddr6;
363 struct nd_defrouter *dr;
364 union nd_opts ndopts;
365 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
366 int mcast;
367
368 /*
369 * We only accept RAs only when the per-interface flag
370 * ND6_IFF_ACCEPT_RTADV is on the receiving interface.
371 */
372 ifp = m->m_pkthdr.rcvif;
373 ndi = ND_IFINFO(ifp);
374 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV))
375 goto freeit;
376
377 /* RFC 6980: Nodes MUST silently ignore fragments */
378 if(m->m_flags & M_FRAGMENTED)
379 goto freeit;
380
381 ip6 = mtod(m, struct ip6_hdr *);
382 if (__predict_false(ip6->ip6_hlim != 255)) {
383 ICMP6STAT_INC(icp6s_invlhlim);
384 nd6log((LOG_ERR,
385 "%s: invalid hlim (%d) from %s to %s on %s\n", __func__,
386 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
387 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
388 goto bad;
389 }
390
391 saddr6 = ip6->ip6_src;
392 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) {
393 nd6log((LOG_ERR,
394 "%s: src %s is not link-local\n", __func__,
395 ip6_sprintf(ip6bufs, &saddr6)));
396 goto bad;
397 }
398
399 if (m->m_len < off + icmp6len) {
400 m = m_pullup(m, off + icmp6len);
401 if (m == NULL) {
402 IP6STAT_INC(ip6s_exthdrtoolong);
403 return;
404 }
405 }
406 ip6 = mtod(m, struct ip6_hdr *);
407 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off);
408
409 icmp6len -= sizeof(*nd_ra);
410 nd6_option_init(nd_ra + 1, icmp6len, &ndopts);
411 if (nd6_options(&ndopts) < 0) {
412 nd6log((LOG_INFO,
413 "%s: invalid ND option, ignored\n", __func__));
414 /* nd6_options have incremented stats */
415 goto freeit;
416 }
417
418 mcast = 0;
419 dr = NULL;
420 {
421 struct nd_defrouter dr0;
422 u_int32_t advreachable = nd_ra->nd_ra_reachable;
423
424 /* remember if this is a multicasted advertisement */
425 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst))
426 mcast = 1;
427
428 bzero(&dr0, sizeof(dr0));
429 dr0.rtaddr = saddr6;
430 dr0.raflags = nd_ra->nd_ra_flags_reserved;
431 /*
432 * Effectively-disable routes from RA messages when
433 * ND6_IFF_NO_RADR enabled on the receiving interface or
434 * (ip6.forwarding == 1 && ip6.rfc6204w3 != 1).
435 */
436 if (ndi->flags & ND6_IFF_NO_RADR)
437 dr0.rtlifetime = 0;
438 else if (V_ip6_forwarding && !V_ip6_rfc6204w3)
439 dr0.rtlifetime = 0;
440 else
441 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime);
442 dr0.expire = time_uptime + dr0.rtlifetime;
443 dr0.ifp = ifp;
444 /* unspecified or not? (RFC 2461 6.3.4) */
445 if (advreachable) {
446 advreachable = ntohl(advreachable);
447 if (advreachable <= MAX_REACHABLE_TIME &&
448 ndi->basereachable != advreachable) {
449 ndi->basereachable = advreachable;
450 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable);
451 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */
452 }
453 }
454 if (nd_ra->nd_ra_retransmit)
455 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit);
456 if (nd_ra->nd_ra_curhoplimit) {
457 if (ndi->chlim < nd_ra->nd_ra_curhoplimit)
458 ndi->chlim = nd_ra->nd_ra_curhoplimit;
459 else if (ndi->chlim != nd_ra->nd_ra_curhoplimit) {
460 log(LOG_ERR, "RA with a lower CurHopLimit sent from "
461 "%s on %s (current = %d, received = %d). "
462 "Ignored.\n", ip6_sprintf(ip6bufs, &ip6->ip6_src),
463 if_name(ifp), ndi->chlim, nd_ra->nd_ra_curhoplimit);
464 }
465 }
466 dr = defrtrlist_update(&dr0);
467 #ifdef EXPERIMENTAL
468 defrtr_ipv6_only_ifp(ifp);
469 #endif
470 }
471
472 /*
473 * prefix
474 */
475 if (ndopts.nd_opts_pi) {
476 struct nd_opt_hdr *pt;
477 struct nd_opt_prefix_info *pi = NULL;
478 struct nd_prefixctl pr;
479
480 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi;
481 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end;
482 pt = (struct nd_opt_hdr *)((caddr_t)pt +
483 (pt->nd_opt_len << 3))) {
484 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION)
485 continue;
486 pi = (struct nd_opt_prefix_info *)pt;
487
488 if (pi->nd_opt_pi_len != 4) {
489 nd6log((LOG_INFO,
490 "%s: invalid option len %d for prefix "
491 "information option, ignored\n", __func__,
492 pi->nd_opt_pi_len));
493 continue;
494 }
495
496 if (128 < pi->nd_opt_pi_prefix_len) {
497 nd6log((LOG_INFO,
498 "%s: invalid prefix len %d for prefix "
499 "information option, ignored\n", __func__,
500 pi->nd_opt_pi_prefix_len));
501 continue;
502 }
503
504 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix)
505 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) {
506 nd6log((LOG_INFO,
507 "%s: invalid prefix %s, ignored\n",
508 __func__, ip6_sprintf(ip6bufs,
509 &pi->nd_opt_pi_prefix)));
510 continue;
511 }
512
513 bzero(&pr, sizeof(pr));
514 pr.ndpr_prefix.sin6_family = AF_INET6;
515 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix);
516 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix;
517 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif;
518
519 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved &
520 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0;
521 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved &
522 ND_OPT_PI_FLAG_AUTO) ? 1 : 0;
523 pr.ndpr_raf_ra_derived = 1;
524 pr.ndpr_plen = pi->nd_opt_pi_prefix_len;
525 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time);
526 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time);
527 (void)prelist_update(&pr, dr, m, mcast);
528 }
529 }
530 if (dr != NULL) {
531 defrouter_rele(dr);
532 dr = NULL;
533 }
534
535 /*
536 * MTU
537 */
538 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) {
539 u_long mtu;
540 u_long maxmtu;
541
542 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
543
544 /* lower bound */
545 if (mtu < IPV6_MMTU) {
546 nd6log((LOG_INFO, "%s: bogus mtu option mtu=%lu sent "
547 "from %s, ignoring\n", __func__,
548 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src)));
549 goto skip;
550 }
551
552 /* upper bound */
553 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu)
554 ? ndi->maxmtu : ifp->if_mtu;
555 if (mtu <= maxmtu) {
556 int change = (ndi->linkmtu != mtu);
557
558 ndi->linkmtu = mtu;
559 if (change) {
560 /* in6_maxmtu may change */
561 in6_setmaxmtu();
562 rt_updatemtu(ifp);
563 }
564 } else {
565 nd6log((LOG_INFO, "%s: bogus mtu=%lu sent from %s; "
566 "exceeds maxmtu %lu, ignoring\n", __func__,
567 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu));
568 }
569 }
570
571 skip:
572
573 /*
574 * Source link layer address
575 */
576 {
577 char *lladdr = NULL;
578 int lladdrlen = 0;
579
580 if (ndopts.nd_opts_src_lladdr) {
581 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
582 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
583 }
584
585 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
586 nd6log((LOG_INFO,
587 "%s: lladdrlen mismatch for %s (if %d, RA packet %d)\n",
588 __func__, ip6_sprintf(ip6bufs, &saddr6),
589 ifp->if_addrlen, lladdrlen - 2));
590 goto bad;
591 }
592
593 nd6_cache_lladdr(ifp, &saddr6, lladdr,
594 lladdrlen, ND_ROUTER_ADVERT, 0);
595
596 /*
597 * Installing a link-layer address might change the state of the
598 * router's neighbor cache, which might also affect our on-link
599 * detection of adveritsed prefixes.
600 */
601 pfxlist_onlink_check();
602 }
603
604 freeit:
605 m_freem(m);
606 return;
607
608 bad:
609 ICMP6STAT_INC(icp6s_badra);
610 m_freem(m);
611 }
612
613 /* PFXRTR */
614 static struct nd_pfxrouter *
pfxrtr_lookup(struct nd_prefix * pr,struct nd_defrouter * dr)615 pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr)
616 {
617 struct nd_pfxrouter *search;
618
619 ND6_LOCK_ASSERT();
620
621 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) {
622 if (search->router == dr)
623 break;
624 }
625 return (search);
626 }
627
628 static void
pfxrtr_add(struct nd_prefix * pr,struct nd_defrouter * dr)629 pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr)
630 {
631 struct nd_pfxrouter *new;
632 bool update;
633
634 ND6_UNLOCK_ASSERT();
635
636 ND6_RLOCK();
637 if (pfxrtr_lookup(pr, dr) != NULL) {
638 ND6_RUNLOCK();
639 return;
640 }
641 ND6_RUNLOCK();
642
643 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO);
644 if (new == NULL)
645 return;
646 defrouter_ref(dr);
647 new->router = dr;
648
649 ND6_WLOCK();
650 if (pfxrtr_lookup(pr, dr) == NULL) {
651 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry);
652 update = true;
653 } else {
654 /* We lost a race to add the reference. */
655 defrouter_rele(dr);
656 free(new, M_IP6NDP);
657 update = false;
658 }
659 ND6_WUNLOCK();
660
661 if (update)
662 pfxlist_onlink_check();
663 }
664
665 static void
pfxrtr_del(struct nd_pfxrouter * pfr)666 pfxrtr_del(struct nd_pfxrouter *pfr)
667 {
668
669 ND6_WLOCK_ASSERT();
670
671 LIST_REMOVE(pfr, pfr_entry);
672 defrouter_rele(pfr->router);
673 free(pfr, M_IP6NDP);
674 }
675
676 /* Default router list processing sub routines. */
677 static void
defrouter_addreq(struct nd_defrouter * new)678 defrouter_addreq(struct nd_defrouter *new)
679 {
680 uint32_t fibnum = new->ifp->if_fib;
681 struct rib_cmd_info rc = {};
682 int error = 0;
683
684 NET_EPOCH_ASSERT();
685
686 struct sockaddr_in6 gw = {
687 .sin6_family = AF_INET6,
688 .sin6_len = sizeof(struct sockaddr_in6),
689 .sin6_addr = new->rtaddr,
690 };
691
692 error = rib_add_default_route(fibnum, AF_INET6, new->ifp,
693 (struct sockaddr *)&gw, &rc);
694
695 if (error == 0) {
696 struct nhop_object *nh = nhop_select_func(rc.rc_nh_new, 0);
697 rt_routemsg(RTM_ADD, rc.rc_rt, nh, fibnum);
698 new->installed = 1;
699 }
700 }
701
702 /*
703 * Remove the default route for a given router.
704 * This is just a subroutine function for defrouter_select_fib(), and
705 * should not be called from anywhere else.
706 */
707 static void
defrouter_delreq(struct nd_defrouter * dr)708 defrouter_delreq(struct nd_defrouter *dr)
709 {
710 uint32_t fibnum = dr->ifp->if_fib;
711 struct epoch_tracker et;
712 struct rib_cmd_info rc;
713 int error;
714
715 struct sockaddr_in6 dst = {
716 .sin6_family = AF_INET6,
717 .sin6_len = sizeof(struct sockaddr_in6),
718 };
719
720 struct sockaddr_in6 gw = {
721 .sin6_family = AF_INET6,
722 .sin6_len = sizeof(struct sockaddr_in6),
723 .sin6_addr = dr->rtaddr,
724 };
725
726 NET_EPOCH_ENTER(et);
727 error = rib_del_route_px(fibnum, (struct sockaddr *)&dst, 0,
728 rib_match_gw, (struct sockaddr *)&gw, 0, &rc);
729 if (error == 0) {
730 struct nhop_object *nh = nhop_select_func(rc.rc_nh_old, 0);
731 rt_routemsg(RTM_DELETE, rc.rc_rt, nh, fibnum);
732 }
733 NET_EPOCH_EXIT(et);
734
735 dr->installed = 0;
736 }
737
738 static void
defrouter_del(struct nd_defrouter * dr)739 defrouter_del(struct nd_defrouter *dr)
740 {
741 struct nd_defrouter *deldr = NULL;
742 struct nd_prefix *pr;
743 struct nd_pfxrouter *pfxrtr;
744
745 ND6_UNLOCK_ASSERT();
746
747 /*
748 * Flush all the routing table entries that use the router
749 * as a next hop.
750 */
751 if (ND_IFINFO(dr->ifp)->flags & ND6_IFF_ACCEPT_RTADV)
752 rt6_flush(&dr->rtaddr, dr->ifp);
753
754 #ifdef EXPERIMENTAL
755 defrtr_ipv6_only_ifp(dr->ifp);
756 #endif
757
758 if (dr->installed) {
759 deldr = dr;
760 defrouter_delreq(dr);
761 }
762
763 /*
764 * Also delete all the pointers to the router in each prefix lists.
765 */
766 ND6_WLOCK();
767 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
768 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL)
769 pfxrtr_del(pfxrtr);
770 }
771 ND6_WUNLOCK();
772
773 pfxlist_onlink_check();
774
775 /*
776 * If the router is the primary one, choose a new one.
777 * Note that defrouter_select_fib() will remove the current
778 * gateway from the routing table.
779 */
780 if (deldr)
781 defrouter_select_fib(deldr->ifp->if_fib);
782
783 /*
784 * Release the list reference.
785 */
786 defrouter_rele(dr);
787 }
788
789 struct nd_defrouter *
defrouter_lookup_locked(const struct in6_addr * addr,struct ifnet * ifp)790 defrouter_lookup_locked(const struct in6_addr *addr, struct ifnet *ifp)
791 {
792 struct nd_defrouter *dr;
793
794 ND6_LOCK_ASSERT();
795 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry)
796 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) {
797 defrouter_ref(dr);
798 return (dr);
799 }
800 return (NULL);
801 }
802
803 struct nd_defrouter *
defrouter_lookup(const struct in6_addr * addr,struct ifnet * ifp)804 defrouter_lookup(const struct in6_addr *addr, struct ifnet *ifp)
805 {
806 struct nd_defrouter *dr;
807
808 ND6_RLOCK();
809 dr = defrouter_lookup_locked(addr, ifp);
810 ND6_RUNLOCK();
811 return (dr);
812 }
813
814 /*
815 * Remove all default routes from default router list.
816 */
817 void
defrouter_reset(void)818 defrouter_reset(void)
819 {
820 struct nd_defrouter *dr, **dra;
821 int count, i;
822
823 count = i = 0;
824
825 /*
826 * We can't delete routes with the ND lock held, so make a copy of the
827 * current default router list and use that when deleting routes.
828 */
829 ND6_RLOCK();
830 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry)
831 count++;
832 ND6_RUNLOCK();
833
834 dra = malloc(count * sizeof(*dra), M_TEMP, M_WAITOK | M_ZERO);
835
836 ND6_RLOCK();
837 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) {
838 if (i == count)
839 break;
840 defrouter_ref(dr);
841 dra[i++] = dr;
842 }
843 ND6_RUNLOCK();
844
845 for (i = 0; i < count && dra[i] != NULL; i++) {
846 defrouter_delreq(dra[i]);
847 defrouter_rele(dra[i]);
848 }
849 free(dra, M_TEMP);
850
851 /*
852 * XXX should we also nuke any default routers in the kernel, by
853 * going through them by rtalloc1()?
854 */
855 }
856
857 /*
858 * Look up a matching default router list entry and remove it. Returns true if a
859 * matching entry was found, false otherwise.
860 */
861 bool
defrouter_remove(struct in6_addr * addr,struct ifnet * ifp)862 defrouter_remove(struct in6_addr *addr, struct ifnet *ifp)
863 {
864 struct nd_defrouter *dr;
865
866 ND6_WLOCK();
867 dr = defrouter_lookup_locked(addr, ifp);
868 if (dr == NULL) {
869 ND6_WUNLOCK();
870 return (false);
871 }
872
873 defrouter_unlink(dr, NULL);
874 ND6_WUNLOCK();
875 defrouter_del(dr);
876 defrouter_rele(dr);
877 return (true);
878 }
879
880 /*
881 * for default router selection
882 * regards router-preference field as a 2-bit signed integer
883 */
884 static int
rtpref(struct nd_defrouter * dr)885 rtpref(struct nd_defrouter *dr)
886 {
887 switch (dr->raflags & ND_RA_FLAG_RTPREF_MASK) {
888 case ND_RA_FLAG_RTPREF_HIGH:
889 return (RTPREF_HIGH);
890 case ND_RA_FLAG_RTPREF_MEDIUM:
891 case ND_RA_FLAG_RTPREF_RSV:
892 return (RTPREF_MEDIUM);
893 case ND_RA_FLAG_RTPREF_LOW:
894 return (RTPREF_LOW);
895 default:
896 /*
897 * This case should never happen. If it did, it would mean a
898 * serious bug of kernel internal. We thus always bark here.
899 * Or, can we even panic?
900 */
901 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->raflags);
902 return (RTPREF_INVALID);
903 }
904 /* NOTREACHED */
905 }
906
907 static bool
is_dr_reachable(const struct nd_defrouter * dr)908 is_dr_reachable(const struct nd_defrouter *dr) {
909 struct llentry *ln = NULL;
910
911 ln = nd6_lookup(&dr->rtaddr, LLE_SF(AF_INET6, 0), dr->ifp);
912 if (ln == NULL)
913 return (false);
914 bool reachable = ND6_IS_LLINFO_PROBREACH(ln);
915 LLE_RUNLOCK(ln);
916 return reachable;
917 }
918
919 /*
920 * Default Router Selection according to Section 6.3.6 of RFC 2461 and
921 * draft-ietf-ipngwg-router-selection:
922 * 1) Routers that are reachable or probably reachable should be preferred.
923 * If we have more than one (probably) reachable router, prefer ones
924 * with the highest router preference.
925 * 2) When no routers on the list are known to be reachable or
926 * probably reachable, routers SHOULD be selected in a round-robin
927 * fashion, regardless of router preference values.
928 * 3) If the Default Router List is empty, assume that all
929 * destinations are on-link.
930 *
931 * We assume nd_defrouter is sorted by router preference value.
932 * Since the code below covers both with and without router preference cases,
933 * we do not need to classify the cases by ifdef.
934 *
935 * At this moment, we do not try to install more than one default router,
936 * even when the multipath routing is available, because we're not sure about
937 * the benefits for stub hosts comparing to the risk of making the code
938 * complicated and the possibility of introducing bugs.
939 *
940 * We maintain a single list of routers for multiple FIBs, only considering one
941 * at a time based on the receiving interface's FIB. If @fibnum is RT_ALL_FIBS,
942 * we do the whole thing multiple times.
943 */
944 void
defrouter_select_fib(int fibnum)945 defrouter_select_fib(int fibnum)
946 {
947 struct epoch_tracker et;
948 struct nd_defrouter *dr, *selected_dr, *installed_dr;
949
950 if (fibnum == RT_ALL_FIBS) {
951 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) {
952 defrouter_select_fib(fibnum);
953 }
954 return;
955 }
956
957 ND6_RLOCK();
958 /*
959 * Let's handle easy case (3) first:
960 * If default router list is empty, there's nothing to be done.
961 */
962 if (TAILQ_EMPTY(&V_nd6_defrouter)) {
963 ND6_RUNLOCK();
964 return;
965 }
966
967 /*
968 * Search for a (probably) reachable router from the list.
969 * We just pick up the first reachable one (if any), assuming that
970 * the ordering rule of the list described in defrtrlist_update().
971 */
972 selected_dr = installed_dr = NULL;
973 NET_EPOCH_ENTER(et);
974 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) {
975 if (dr->ifp->if_fib != fibnum)
976 continue;
977
978 if (selected_dr == NULL && is_dr_reachable(dr)) {
979 selected_dr = dr;
980 defrouter_ref(selected_dr);
981 }
982
983 if (dr->installed) {
984 if (installed_dr == NULL) {
985 installed_dr = dr;
986 defrouter_ref(installed_dr);
987 } else {
988 /*
989 * this should not happen.
990 * warn for diagnosis.
991 */
992 log(LOG_ERR, "defrouter_select_fib: more than "
993 "one router is installed\n");
994 }
995 }
996 }
997
998 /*
999 * If none of the default routers was found to be reachable,
1000 * round-robin the list regardless of preference.
1001 * Otherwise, if we have an installed router, check if the selected
1002 * (reachable) router should really be preferred to the installed one.
1003 * We only prefer the new router when the old one is not reachable
1004 * or when the new one has a really higher preference value.
1005 */
1006 if (selected_dr == NULL) {
1007 if (installed_dr == NULL ||
1008 TAILQ_NEXT(installed_dr, dr_entry) == NULL)
1009 dr = TAILQ_FIRST(&V_nd6_defrouter);
1010 else
1011 dr = TAILQ_NEXT(installed_dr, dr_entry);
1012
1013 /* Ensure we select a router for this FIB. */
1014 TAILQ_FOREACH_FROM(dr, &V_nd6_defrouter, dr_entry) {
1015 if (dr->ifp->if_fib == fibnum) {
1016 selected_dr = dr;
1017 defrouter_ref(selected_dr);
1018 break;
1019 }
1020 }
1021 } else if (installed_dr != NULL) {
1022 if (is_dr_reachable(installed_dr) &&
1023 rtpref(selected_dr) <= rtpref(installed_dr)) {
1024 defrouter_rele(selected_dr);
1025 selected_dr = installed_dr;
1026 }
1027 }
1028 ND6_RUNLOCK();
1029
1030 /*
1031 * If we selected a router for this FIB and it's different
1032 * than the installed one, remove the installed router and
1033 * install the selected one in its place.
1034 */
1035 if (installed_dr != selected_dr) {
1036 if (installed_dr != NULL) {
1037 defrouter_delreq(installed_dr);
1038 defrouter_rele(installed_dr);
1039 }
1040 if (selected_dr != NULL)
1041 defrouter_addreq(selected_dr);
1042 }
1043 if (selected_dr != NULL)
1044 defrouter_rele(selected_dr);
1045 NET_EPOCH_EXIT(et);
1046 }
1047
1048 static struct nd_defrouter *
defrtrlist_update(struct nd_defrouter * new)1049 defrtrlist_update(struct nd_defrouter *new)
1050 {
1051 struct nd_defrouter *dr, *n;
1052 uint64_t genid;
1053 int oldpref;
1054 bool writelocked;
1055
1056 if (new->rtlifetime == 0) {
1057 defrouter_remove(&new->rtaddr, new->ifp);
1058 return (NULL);
1059 }
1060
1061 ND6_RLOCK();
1062 writelocked = false;
1063 restart:
1064 dr = defrouter_lookup_locked(&new->rtaddr, new->ifp);
1065 if (dr != NULL) {
1066 oldpref = rtpref(dr);
1067
1068 /* override */
1069 dr->raflags = new->raflags; /* XXX flag check */
1070 dr->rtlifetime = new->rtlifetime;
1071 dr->expire = new->expire;
1072
1073 /*
1074 * If the preference does not change, there's no need
1075 * to sort the entries. Also make sure the selected
1076 * router is still installed in the kernel.
1077 */
1078 if (dr->installed && rtpref(new) == oldpref) {
1079 if (writelocked)
1080 ND6_WUNLOCK();
1081 else
1082 ND6_RUNLOCK();
1083 return (dr);
1084 }
1085 }
1086
1087 /*
1088 * The router needs to be reinserted into the default router
1089 * list, so upgrade to a write lock. If that fails and the list
1090 * has potentially changed while the lock was dropped, we'll
1091 * redo the lookup with the write lock held.
1092 */
1093 if (!writelocked) {
1094 writelocked = true;
1095 if (!ND6_TRY_UPGRADE()) {
1096 genid = V_nd6_list_genid;
1097 ND6_RUNLOCK();
1098 ND6_WLOCK();
1099 if (genid != V_nd6_list_genid)
1100 goto restart;
1101 }
1102 }
1103
1104 if (dr != NULL) {
1105 /*
1106 * The preferred router may have changed, so relocate this
1107 * router.
1108 */
1109 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry);
1110 n = dr;
1111 } else {
1112 n = malloc(sizeof(*n), M_IP6NDP, M_NOWAIT | M_ZERO);
1113 if (n == NULL) {
1114 ND6_WUNLOCK();
1115 return (NULL);
1116 }
1117 memcpy(n, new, sizeof(*n));
1118 /* Initialize with an extra reference for the caller. */
1119 refcount_init(&n->refcnt, 2);
1120 }
1121
1122 /*
1123 * Insert the new router in the Default Router List;
1124 * The Default Router List should be in the descending order
1125 * of router-preferece. Routers with the same preference are
1126 * sorted in the arriving time order.
1127 */
1128
1129 /* insert at the end of the group */
1130 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) {
1131 if (rtpref(n) > rtpref(dr))
1132 break;
1133 }
1134 if (dr != NULL)
1135 TAILQ_INSERT_BEFORE(dr, n, dr_entry);
1136 else
1137 TAILQ_INSERT_TAIL(&V_nd6_defrouter, n, dr_entry);
1138 V_nd6_list_genid++;
1139 ND6_WUNLOCK();
1140
1141 defrouter_select_fib(new->ifp->if_fib);
1142
1143 return (n);
1144 }
1145
1146 static int
in6_init_prefix_ltimes(struct nd_prefix * ndpr)1147 in6_init_prefix_ltimes(struct nd_prefix *ndpr)
1148 {
1149 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME)
1150 ndpr->ndpr_preferred = 0;
1151 else
1152 ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime;
1153 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME)
1154 ndpr->ndpr_expire = 0;
1155 else
1156 ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime;
1157
1158 return 0;
1159 }
1160
1161 static void
in6_init_address_ltimes(struct nd_prefix * new,struct in6_addrlifetime * lt6)1162 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6)
1163 {
1164 /* init ia6t_expire */
1165 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME)
1166 lt6->ia6t_expire = 0;
1167 else {
1168 lt6->ia6t_expire = time_uptime;
1169 lt6->ia6t_expire += lt6->ia6t_vltime;
1170 }
1171
1172 /* init ia6t_preferred */
1173 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME)
1174 lt6->ia6t_preferred = 0;
1175 else {
1176 lt6->ia6t_preferred = time_uptime;
1177 lt6->ia6t_preferred += lt6->ia6t_pltime;
1178 }
1179 }
1180
1181 static struct in6_ifaddr *
in6_ifadd(struct nd_prefixctl * pr,int mcast)1182 in6_ifadd(struct nd_prefixctl *pr, int mcast)
1183 {
1184 struct ifnet *ifp = pr->ndpr_ifp;
1185 struct ifaddr *ifa;
1186 struct in6_aliasreq ifra;
1187 struct in6_ifaddr *ia, *ib;
1188 int error, plen0;
1189 struct in6_addr mask;
1190 int prefixlen = pr->ndpr_plen;
1191 int updateflags;
1192 char ip6buf[INET6_ADDRSTRLEN];
1193
1194 in6_prefixlen2mask(&mask, prefixlen);
1195
1196 /*
1197 * find a link-local address (will be interface ID).
1198 * Is it really mandatory? Theoretically, a global or a site-local
1199 * address can be configured without a link-local address, if we
1200 * have a unique interface identifier...
1201 *
1202 * it is not mandatory to have a link-local address, we can generate
1203 * interface identifier on the fly. we do this because:
1204 * (1) it should be the easiest way to find interface identifier.
1205 * (2) RFC2462 5.4 suggesting the use of the same interface identifier
1206 * for multiple addresses on a single interface, and possible shortcut
1207 * of DAD. we omitted DAD for this reason in the past.
1208 * (3) a user can prevent autoconfiguration of global address
1209 * by removing link-local address by hand (this is partly because we
1210 * don't have other way to control the use of IPv6 on an interface.
1211 * this has been our design choice - cf. NRL's "ifconfig auto").
1212 * (4) it is easier to manage when an interface has addresses
1213 * with the same interface identifier, than to have multiple addresses
1214 * with different interface identifiers.
1215 */
1216 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */
1217 if (ifa)
1218 ib = (struct in6_ifaddr *)ifa;
1219 else
1220 return NULL;
1221
1222 /* prefixlen + ifidlen must be equal to 128 */
1223 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL);
1224 if (prefixlen != plen0) {
1225 ifa_free(ifa);
1226 nd6log((LOG_INFO,
1227 "%s: wrong prefixlen for %s (prefix=%d ifid=%d)\n",
1228 __func__, if_name(ifp), prefixlen, 128 - plen0));
1229 return NULL;
1230 }
1231
1232 /* make ifaddr */
1233 in6_prepare_ifra(&ifra, &pr->ndpr_prefix.sin6_addr, &mask);
1234
1235 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, &mask);
1236 /* interface ID */
1237 ifra.ifra_addr.sin6_addr.s6_addr32[0] |=
1238 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]);
1239 ifra.ifra_addr.sin6_addr.s6_addr32[1] |=
1240 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]);
1241 ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
1242 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]);
1243 ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
1244 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]);
1245 ifa_free(ifa);
1246
1247 /* lifetimes. */
1248 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime;
1249 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime;
1250
1251 /* XXX: scope zone ID? */
1252
1253 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */
1254
1255 /*
1256 * Make sure that we do not have this address already. This should
1257 * usually not happen, but we can still see this case, e.g., if we
1258 * have manually configured the exact address to be configured.
1259 */
1260 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp,
1261 &ifra.ifra_addr.sin6_addr);
1262 if (ifa != NULL) {
1263 ifa_free(ifa);
1264 /* this should be rare enough to make an explicit log */
1265 log(LOG_INFO, "in6_ifadd: %s is already configured\n",
1266 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr));
1267 return (NULL);
1268 }
1269
1270 /*
1271 * Allocate ifaddr structure, link into chain, etc.
1272 * If we are going to create a new address upon receiving a multicasted
1273 * RA, we need to impose a random delay before starting DAD.
1274 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2]
1275 */
1276 updateflags = 0;
1277 if (mcast)
1278 updateflags |= IN6_IFAUPDATE_DADDELAY;
1279 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) {
1280 nd6log((LOG_ERR,
1281 "%s: failed to make ifaddr %s on %s (errno=%d)\n", __func__,
1282 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr),
1283 if_name(ifp), error));
1284 return (NULL); /* ifaddr must not have been allocated. */
1285 }
1286
1287 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
1288 /*
1289 * XXXRW: Assumption of non-NULLness here might not be true with
1290 * fine-grained locking -- should we validate it? Or just return
1291 * earlier ifa rather than looking it up again?
1292 */
1293 return (ia); /* this is always non-NULL and referenced. */
1294 }
1295
1296 static struct nd_prefix *
nd6_prefix_lookup_locked(struct nd_prefixctl * key)1297 nd6_prefix_lookup_locked(struct nd_prefixctl *key)
1298 {
1299 struct nd_prefix *search;
1300
1301 ND6_LOCK_ASSERT();
1302
1303 LIST_FOREACH(search, &V_nd_prefix, ndpr_entry) {
1304 if (key->ndpr_ifp == search->ndpr_ifp &&
1305 key->ndpr_plen == search->ndpr_plen &&
1306 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr,
1307 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) {
1308 nd6_prefix_ref(search);
1309 break;
1310 }
1311 }
1312 return (search);
1313 }
1314
1315 struct nd_prefix *
nd6_prefix_lookup(struct nd_prefixctl * key)1316 nd6_prefix_lookup(struct nd_prefixctl *key)
1317 {
1318 struct nd_prefix *search;
1319
1320 ND6_RLOCK();
1321 search = nd6_prefix_lookup_locked(key);
1322 ND6_RUNLOCK();
1323 return (search);
1324 }
1325
1326 void
nd6_prefix_ref(struct nd_prefix * pr)1327 nd6_prefix_ref(struct nd_prefix *pr)
1328 {
1329
1330 refcount_acquire(&pr->ndpr_refcnt);
1331 }
1332
1333 void
nd6_prefix_rele(struct nd_prefix * pr)1334 nd6_prefix_rele(struct nd_prefix *pr)
1335 {
1336
1337 if (refcount_release(&pr->ndpr_refcnt)) {
1338 KASSERT(LIST_EMPTY(&pr->ndpr_advrtrs),
1339 ("prefix %p has advertising routers", pr));
1340 free(pr, M_IP6NDP);
1341 }
1342 }
1343
1344 int
nd6_prelist_add(struct nd_prefixctl * pr,struct nd_defrouter * dr,struct nd_prefix ** newp)1345 nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr,
1346 struct nd_prefix **newp)
1347 {
1348 struct nd_prefix *new;
1349 char ip6buf[INET6_ADDRSTRLEN];
1350 int error;
1351
1352 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO);
1353 if (new == NULL)
1354 return (ENOMEM);
1355 refcount_init(&new->ndpr_refcnt, newp != NULL ? 2 : 1);
1356 new->ndpr_ifp = pr->ndpr_ifp;
1357 new->ndpr_prefix = pr->ndpr_prefix;
1358 new->ndpr_plen = pr->ndpr_plen;
1359 new->ndpr_vltime = pr->ndpr_vltime;
1360 new->ndpr_pltime = pr->ndpr_pltime;
1361 new->ndpr_flags = pr->ndpr_flags;
1362 if ((error = in6_init_prefix_ltimes(new)) != 0) {
1363 free(new, M_IP6NDP);
1364 return (error);
1365 }
1366 new->ndpr_lastupdate = time_uptime;
1367
1368 /* initialization */
1369 LIST_INIT(&new->ndpr_advrtrs);
1370 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen);
1371 /* make prefix in the canonical form */
1372 IN6_MASK_ADDR(&new->ndpr_prefix.sin6_addr, &new->ndpr_mask);
1373
1374 ND6_WLOCK();
1375 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry);
1376 V_nd6_list_genid++;
1377 ND6_WUNLOCK();
1378
1379 /* ND_OPT_PI_FLAG_ONLINK processing */
1380 if (new->ndpr_raf_onlink) {
1381 struct epoch_tracker et;
1382
1383 ND6_ONLINK_LOCK();
1384 NET_EPOCH_ENTER(et);
1385 if ((error = nd6_prefix_onlink(new)) != 0) {
1386 nd6log((LOG_ERR, "%s: failed to make the prefix %s/%d "
1387 "on-link on %s (errno=%d)\n", __func__,
1388 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
1389 pr->ndpr_plen, if_name(pr->ndpr_ifp), error));
1390 /* proceed anyway. XXX: is it correct? */
1391 }
1392 NET_EPOCH_EXIT(et);
1393 ND6_ONLINK_UNLOCK();
1394 }
1395
1396 if (dr != NULL)
1397 pfxrtr_add(new, dr);
1398 if (newp != NULL)
1399 *newp = new;
1400 return (0);
1401 }
1402
1403 /*
1404 * Remove a prefix from the prefix list and optionally stash it in a
1405 * caller-provided list.
1406 *
1407 * The ND6 lock must be held.
1408 */
1409 void
nd6_prefix_unlink(struct nd_prefix * pr,struct nd_prhead * list)1410 nd6_prefix_unlink(struct nd_prefix *pr, struct nd_prhead *list)
1411 {
1412
1413 ND6_WLOCK_ASSERT();
1414
1415 LIST_REMOVE(pr, ndpr_entry);
1416 V_nd6_list_genid++;
1417 if (list != NULL)
1418 LIST_INSERT_HEAD(list, pr, ndpr_entry);
1419 }
1420
1421 /*
1422 * Free an unlinked prefix, first marking it off-link if necessary.
1423 */
1424 void
nd6_prefix_del(struct nd_prefix * pr)1425 nd6_prefix_del(struct nd_prefix *pr)
1426 {
1427 struct nd_pfxrouter *pfr, *next;
1428 int e;
1429 char ip6buf[INET6_ADDRSTRLEN];
1430
1431 KASSERT(pr->ndpr_addrcnt == 0,
1432 ("prefix %p has referencing addresses", pr));
1433 ND6_UNLOCK_ASSERT();
1434
1435 /*
1436 * Though these flags are now meaningless, we'd rather keep the value
1437 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users
1438 * when executing "ndp -p".
1439 */
1440 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
1441 ND6_ONLINK_LOCK();
1442 if ((e = nd6_prefix_offlink(pr)) != 0) {
1443 nd6log((LOG_ERR,
1444 "%s: failed to make the prefix %s/%d offlink on %s "
1445 "(errno=%d)\n", __func__,
1446 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
1447 pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
1448 /* what should we do? */
1449 }
1450 ND6_ONLINK_UNLOCK();
1451 }
1452
1453 /* Release references to routers that have advertised this prefix. */
1454 ND6_WLOCK();
1455 LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next)
1456 pfxrtr_del(pfr);
1457 ND6_WUNLOCK();
1458
1459 nd6_prefix_rele(pr);
1460
1461 pfxlist_onlink_check();
1462 }
1463
1464 static int
prelist_update(struct nd_prefixctl * new,struct nd_defrouter * dr,struct mbuf * m,int mcast)1465 prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr,
1466 struct mbuf *m, int mcast)
1467 {
1468 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL;
1469 struct ifaddr *ifa;
1470 struct ifnet *ifp = new->ndpr_ifp;
1471 struct nd_prefix *pr;
1472 int error = 0;
1473 int auth;
1474 struct in6_addrlifetime lt6_tmp;
1475 char ip6buf[INET6_ADDRSTRLEN];
1476
1477 NET_EPOCH_ASSERT();
1478
1479 auth = 0;
1480 if (m) {
1481 /*
1482 * Authenticity for NA consists authentication for
1483 * both IP header and IP datagrams, doesn't it ?
1484 */
1485 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM)
1486 auth = ((m->m_flags & M_AUTHIPHDR) &&
1487 (m->m_flags & M_AUTHIPDGM));
1488 #endif
1489 }
1490
1491 if ((pr = nd6_prefix_lookup(new)) != NULL) {
1492 /*
1493 * nd6_prefix_lookup() ensures that pr and new have the same
1494 * prefix on a same interface.
1495 */
1496
1497 /*
1498 * Update prefix information. Note that the on-link (L) bit
1499 * and the autonomous (A) bit should NOT be changed from 1
1500 * to 0.
1501 */
1502 if (new->ndpr_raf_onlink == 1)
1503 pr->ndpr_raf_onlink = 1;
1504 if (new->ndpr_raf_auto == 1)
1505 pr->ndpr_raf_auto = 1;
1506 if (new->ndpr_raf_onlink) {
1507 pr->ndpr_vltime = new->ndpr_vltime;
1508 pr->ndpr_pltime = new->ndpr_pltime;
1509 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */
1510 pr->ndpr_lastupdate = time_uptime;
1511 }
1512
1513 if (new->ndpr_raf_onlink &&
1514 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
1515 ND6_ONLINK_LOCK();
1516 if ((error = nd6_prefix_onlink(pr)) != 0) {
1517 nd6log((LOG_ERR,
1518 "%s: failed to make the prefix %s/%d "
1519 "on-link on %s (errno=%d)\n", __func__,
1520 ip6_sprintf(ip6buf,
1521 &pr->ndpr_prefix.sin6_addr),
1522 pr->ndpr_plen, if_name(pr->ndpr_ifp),
1523 error));
1524 /* proceed anyway. XXX: is it correct? */
1525 }
1526 ND6_ONLINK_UNLOCK();
1527 }
1528
1529 if (dr != NULL)
1530 pfxrtr_add(pr, dr);
1531 } else {
1532 if (new->ndpr_vltime == 0)
1533 goto end;
1534 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0)
1535 goto end;
1536
1537 error = nd6_prelist_add(new, dr, &pr);
1538 if (error != 0) {
1539 nd6log((LOG_NOTICE, "%s: nd6_prelist_add() failed for "
1540 "the prefix %s/%d on %s (errno=%d)\n", __func__,
1541 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr),
1542 new->ndpr_plen, if_name(new->ndpr_ifp), error));
1543 goto end; /* we should just give up in this case. */
1544 }
1545
1546 /*
1547 * XXX: from the ND point of view, we can ignore a prefix
1548 * with the on-link bit being zero. However, we need a
1549 * prefix structure for references from autoconfigured
1550 * addresses. Thus, we explicitly make sure that the prefix
1551 * itself expires now.
1552 */
1553 if (pr->ndpr_raf_onlink == 0) {
1554 pr->ndpr_vltime = 0;
1555 pr->ndpr_pltime = 0;
1556 in6_init_prefix_ltimes(pr);
1557 }
1558 }
1559
1560 /*
1561 * Address autoconfiguration based on Section 5.5.3 of RFC 2462.
1562 * Note that pr must be non NULL at this point.
1563 */
1564
1565 /* 5.5.3 (a). Ignore the prefix without the A bit set. */
1566 if (!new->ndpr_raf_auto)
1567 goto end;
1568
1569 /*
1570 * 5.5.3 (b). the link-local prefix should have been ignored in
1571 * nd6_ra_input.
1572 */
1573
1574 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */
1575 if (new->ndpr_pltime > new->ndpr_vltime) {
1576 error = EINVAL; /* XXX: won't be used */
1577 goto end;
1578 }
1579
1580 /*
1581 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of
1582 * an address configured by stateless autoconfiguration already in the
1583 * list of addresses associated with the interface, and the Valid
1584 * Lifetime is not 0, form an address. We first check if we have
1585 * a matching prefix.
1586 * Note: we apply a clarification in rfc2462bis-02 here. We only
1587 * consider autoconfigured addresses while RFC2462 simply said
1588 * "address".
1589 */
1590 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1591 struct in6_ifaddr *ifa6;
1592 u_int32_t remaininglifetime;
1593
1594 if (ifa->ifa_addr->sa_family != AF_INET6)
1595 continue;
1596
1597 ifa6 = (struct in6_ifaddr *)ifa;
1598
1599 /*
1600 * We only consider autoconfigured addresses as per rfc2462bis.
1601 */
1602 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF))
1603 continue;
1604
1605 /*
1606 * Spec is not clear here, but I believe we should concentrate
1607 * on unicast (i.e. not anycast) addresses.
1608 * XXX: other ia6_flags? detached or duplicated?
1609 */
1610 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0)
1611 continue;
1612
1613 /*
1614 * Ignore the address if it is not associated with a prefix
1615 * or is associated with a prefix that is different from this
1616 * one. (pr is never NULL here)
1617 */
1618 if (ifa6->ia6_ndpr != pr)
1619 continue;
1620
1621 if (ia6_match == NULL) /* remember the first one */
1622 ia6_match = ifa6;
1623
1624 /*
1625 * An already autoconfigured address matched. Now that we
1626 * are sure there is at least one matched address, we can
1627 * proceed to 5.5.3. (e): update the lifetimes according to the
1628 * "two hours" rule and the privacy extension.
1629 * We apply some clarifications in rfc2462bis:
1630 * - use remaininglifetime instead of storedlifetime as a
1631 * variable name
1632 * - remove the dead code in the "two-hour" rule
1633 */
1634 #define TWOHOUR (120*60)
1635 lt6_tmp = ifa6->ia6_lifetime;
1636
1637 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME)
1638 remaininglifetime = ND6_INFINITE_LIFETIME;
1639 else if (time_uptime - ifa6->ia6_updatetime >
1640 lt6_tmp.ia6t_vltime) {
1641 /*
1642 * The case of "invalid" address. We should usually
1643 * not see this case.
1644 */
1645 remaininglifetime = 0;
1646 } else
1647 remaininglifetime = lt6_tmp.ia6t_vltime -
1648 (time_uptime - ifa6->ia6_updatetime);
1649
1650 /* when not updating, keep the current stored lifetime. */
1651 lt6_tmp.ia6t_vltime = remaininglifetime;
1652
1653 if (TWOHOUR < new->ndpr_vltime ||
1654 remaininglifetime < new->ndpr_vltime) {
1655 lt6_tmp.ia6t_vltime = new->ndpr_vltime;
1656 } else if (remaininglifetime <= TWOHOUR) {
1657 if (auth) {
1658 lt6_tmp.ia6t_vltime = new->ndpr_vltime;
1659 }
1660 } else {
1661 /*
1662 * new->ndpr_vltime <= TWOHOUR &&
1663 * TWOHOUR < remaininglifetime
1664 */
1665 lt6_tmp.ia6t_vltime = TWOHOUR;
1666 }
1667
1668 /* The 2 hour rule is not imposed for preferred lifetime. */
1669 lt6_tmp.ia6t_pltime = new->ndpr_pltime;
1670
1671 in6_init_address_ltimes(pr, <6_tmp);
1672
1673 /*
1674 * We need to treat lifetimes for temporary addresses
1675 * differently, according to
1676 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1);
1677 * we only update the lifetimes when they are in the maximum
1678 * intervals.
1679 */
1680 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
1681 u_int32_t maxvltime, maxpltime;
1682
1683 if (V_ip6_temp_valid_lifetime >
1684 (u_int32_t)((time_uptime - ifa6->ia6_createtime) +
1685 V_ip6_desync_factor)) {
1686 maxvltime = V_ip6_temp_valid_lifetime -
1687 (time_uptime - ifa6->ia6_createtime) -
1688 V_ip6_desync_factor;
1689 } else
1690 maxvltime = 0;
1691 if (V_ip6_temp_preferred_lifetime >
1692 (u_int32_t)((time_uptime - ifa6->ia6_createtime) +
1693 V_ip6_desync_factor)) {
1694 maxpltime = V_ip6_temp_preferred_lifetime -
1695 (time_uptime - ifa6->ia6_createtime) -
1696 V_ip6_desync_factor;
1697 } else
1698 maxpltime = 0;
1699
1700 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME ||
1701 lt6_tmp.ia6t_vltime > maxvltime) {
1702 lt6_tmp.ia6t_vltime = maxvltime;
1703 }
1704 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME ||
1705 lt6_tmp.ia6t_pltime > maxpltime) {
1706 lt6_tmp.ia6t_pltime = maxpltime;
1707 }
1708 }
1709 ifa6->ia6_lifetime = lt6_tmp;
1710 ifa6->ia6_updatetime = time_uptime;
1711 }
1712 if (ia6_match == NULL && new->ndpr_vltime) {
1713 int ifidlen;
1714
1715 /*
1716 * 5.5.3 (d) (continued)
1717 * No address matched and the valid lifetime is non-zero.
1718 * Create a new address.
1719 */
1720
1721 /*
1722 * Prefix Length check:
1723 * If the sum of the prefix length and interface identifier
1724 * length does not equal 128 bits, the Prefix Information
1725 * option MUST be ignored. The length of the interface
1726 * identifier is defined in a separate link-type specific
1727 * document.
1728 */
1729 ifidlen = in6_if2idlen(ifp);
1730 if (ifidlen < 0) {
1731 /* this should not happen, so we always log it. */
1732 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n",
1733 if_name(ifp));
1734 goto end;
1735 }
1736 if (ifidlen + pr->ndpr_plen != 128) {
1737 nd6log((LOG_INFO,
1738 "%s: invalid prefixlen %d for %s, ignored\n",
1739 __func__, pr->ndpr_plen, if_name(ifp)));
1740 goto end;
1741 }
1742
1743 if ((ia6 = in6_ifadd(new, mcast)) != NULL) {
1744 /*
1745 * note that we should use pr (not new) for reference.
1746 */
1747 pr->ndpr_addrcnt++;
1748 ia6->ia6_ndpr = pr;
1749
1750 /*
1751 * RFC 3041 3.3 (2).
1752 * When a new public address is created as described
1753 * in RFC2462, also create a new temporary address.
1754 *
1755 * RFC 3041 3.5.
1756 * When an interface connects to a new link, a new
1757 * randomized interface identifier should be generated
1758 * immediately together with a new set of temporary
1759 * addresses. Thus, we specifiy 1 as the 2nd arg of
1760 * in6_tmpifadd().
1761 */
1762 if (V_ip6_use_tempaddr) {
1763 int e;
1764 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) {
1765 nd6log((LOG_NOTICE, "%s: failed to "
1766 "create a temporary address "
1767 "(errno=%d)\n", __func__, e));
1768 }
1769 }
1770 ifa_free(&ia6->ia_ifa);
1771
1772 /*
1773 * A newly added address might affect the status
1774 * of other addresses, so we check and update it.
1775 * XXX: what if address duplication happens?
1776 */
1777 pfxlist_onlink_check();
1778 } else {
1779 /* just set an error. do not bark here. */
1780 error = EADDRNOTAVAIL; /* XXX: might be unused. */
1781 }
1782 }
1783
1784 end:
1785 if (pr != NULL)
1786 nd6_prefix_rele(pr);
1787 return (error);
1788 }
1789
1790 /*
1791 * A supplement function used in the on-link detection below;
1792 * detect if a given prefix has a (probably) reachable advertising router.
1793 * XXX: lengthy function name...
1794 */
1795 static struct nd_pfxrouter *
find_pfxlist_reachable_router(struct nd_prefix * pr)1796 find_pfxlist_reachable_router(struct nd_prefix *pr)
1797 {
1798 struct epoch_tracker et;
1799 struct nd_pfxrouter *pfxrtr;
1800
1801 ND6_LOCK_ASSERT();
1802
1803 NET_EPOCH_ENTER(et);
1804 LIST_FOREACH(pfxrtr, &pr->ndpr_advrtrs, pfr_entry) {
1805 if (is_dr_reachable(pfxrtr->router))
1806 break;
1807 }
1808 NET_EPOCH_EXIT(et);
1809 return (pfxrtr);
1810 }
1811
1812 /*
1813 * Check if each prefix in the prefix list has at least one available router
1814 * that advertised the prefix (a router is "available" if its neighbor cache
1815 * entry is reachable or probably reachable).
1816 * If the check fails, the prefix may be off-link, because, for example,
1817 * we have moved from the network but the lifetime of the prefix has not
1818 * expired yet. So we should not use the prefix if there is another prefix
1819 * that has an available router.
1820 * But, if there is no prefix that has an available router, we still regard
1821 * all the prefixes as on-link. This is because we can't tell if all the
1822 * routers are simply dead or if we really moved from the network and there
1823 * is no router around us.
1824 */
1825 void
pfxlist_onlink_check(void)1826 pfxlist_onlink_check(void)
1827 {
1828 struct nd_prefix *pr;
1829 struct in6_ifaddr *ifa;
1830 struct nd_defrouter *dr;
1831 struct nd_pfxrouter *pfxrtr = NULL;
1832 struct rm_priotracker in6_ifa_tracker;
1833 uint64_t genid;
1834 uint32_t flags;
1835
1836 ND6_ONLINK_LOCK();
1837 ND6_RLOCK();
1838
1839 /*
1840 * Check if there is a prefix that has a reachable advertising
1841 * router.
1842 */
1843 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1844 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr))
1845 break;
1846 }
1847
1848 /*
1849 * If we have no such prefix, check whether we still have a router
1850 * that does not advertise any prefixes.
1851 */
1852 if (pr == NULL) {
1853 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) {
1854 struct nd_prefix *pr0;
1855
1856 LIST_FOREACH(pr0, &V_nd_prefix, ndpr_entry) {
1857 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL)
1858 break;
1859 }
1860 if (pfxrtr != NULL)
1861 break;
1862 }
1863 }
1864 if (pr != NULL || (!TAILQ_EMPTY(&V_nd6_defrouter) && pfxrtr == NULL)) {
1865 /*
1866 * There is at least one prefix that has a reachable router,
1867 * or at least a router which probably does not advertise
1868 * any prefixes. The latter would be the case when we move
1869 * to a new link where we have a router that does not provide
1870 * prefixes and we configure an address by hand.
1871 * Detach prefixes which have no reachable advertising
1872 * router, and attach other prefixes.
1873 */
1874 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1875 /* XXX: a link-local prefix should never be detached */
1876 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) ||
1877 pr->ndpr_raf_onlink == 0 ||
1878 pr->ndpr_raf_auto == 0)
1879 continue;
1880
1881 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 &&
1882 find_pfxlist_reachable_router(pr) == NULL)
1883 pr->ndpr_stateflags |= NDPRF_DETACHED;
1884 else if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 &&
1885 find_pfxlist_reachable_router(pr) != NULL)
1886 pr->ndpr_stateflags &= ~NDPRF_DETACHED;
1887 }
1888 } else {
1889 /* there is no prefix that has a reachable router */
1890 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1891 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) ||
1892 pr->ndpr_raf_onlink == 0 ||
1893 pr->ndpr_raf_auto == 0)
1894 continue;
1895 pr->ndpr_stateflags &= ~NDPRF_DETACHED;
1896 }
1897 }
1898
1899 /*
1900 * Remove each interface route associated with a (just) detached
1901 * prefix, and reinstall the interface route for a (just) attached
1902 * prefix. Note that all attempt of reinstallation does not
1903 * necessarily success, when a same prefix is shared among multiple
1904 * interfaces. Such cases will be handled in nd6_prefix_onlink,
1905 * so we don't have to care about them.
1906 */
1907 restart:
1908 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1909 char ip6buf[INET6_ADDRSTRLEN];
1910 int e;
1911
1912 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) ||
1913 pr->ndpr_raf_onlink == 0 ||
1914 pr->ndpr_raf_auto == 0)
1915 continue;
1916
1917 flags = pr->ndpr_stateflags & (NDPRF_DETACHED | NDPRF_ONLINK);
1918 if (flags == 0 || flags == (NDPRF_DETACHED | NDPRF_ONLINK)) {
1919 genid = V_nd6_list_genid;
1920 ND6_RUNLOCK();
1921 if ((flags & NDPRF_ONLINK) != 0 &&
1922 (e = nd6_prefix_offlink(pr)) != 0) {
1923 nd6log((LOG_ERR,
1924 "%s: failed to make %s/%d offlink "
1925 "(errno=%d)\n", __func__,
1926 ip6_sprintf(ip6buf,
1927 &pr->ndpr_prefix.sin6_addr),
1928 pr->ndpr_plen, e));
1929 } else if ((flags & NDPRF_ONLINK) == 0 &&
1930 (e = nd6_prefix_onlink(pr)) != 0) {
1931 nd6log((LOG_ERR,
1932 "%s: failed to make %s/%d onlink "
1933 "(errno=%d)\n", __func__,
1934 ip6_sprintf(ip6buf,
1935 &pr->ndpr_prefix.sin6_addr),
1936 pr->ndpr_plen, e));
1937 }
1938 ND6_RLOCK();
1939 if (genid != V_nd6_list_genid)
1940 goto restart;
1941 }
1942 }
1943
1944 /*
1945 * Changes on the prefix status might affect address status as well.
1946 * Make sure that all addresses derived from an attached prefix are
1947 * attached, and that all addresses derived from a detached prefix are
1948 * detached. Note, however, that a manually configured address should
1949 * always be attached.
1950 * The precise detection logic is same as the one for prefixes.
1951 */
1952 IN6_IFADDR_RLOCK(&in6_ifa_tracker);
1953 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) {
1954 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF))
1955 continue;
1956
1957 if (ifa->ia6_ndpr == NULL) {
1958 /*
1959 * This can happen when we first configure the address
1960 * (i.e. the address exists, but the prefix does not).
1961 * XXX: complicated relationships...
1962 */
1963 continue;
1964 }
1965
1966 if (find_pfxlist_reachable_router(ifa->ia6_ndpr))
1967 break;
1968 }
1969 if (ifa) {
1970 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) {
1971 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1972 continue;
1973
1974 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */
1975 continue;
1976
1977 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) {
1978 if (ifa->ia6_flags & IN6_IFF_DETACHED) {
1979 ifa->ia6_flags &= ~IN6_IFF_DETACHED;
1980 ifa->ia6_flags |= IN6_IFF_TENTATIVE;
1981 nd6_dad_start((struct ifaddr *)ifa, 0);
1982 }
1983 } else {
1984 ifa->ia6_flags |= IN6_IFF_DETACHED;
1985 }
1986 }
1987 } else {
1988 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) {
1989 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1990 continue;
1991
1992 if (ifa->ia6_flags & IN6_IFF_DETACHED) {
1993 ifa->ia6_flags &= ~IN6_IFF_DETACHED;
1994 ifa->ia6_flags |= IN6_IFF_TENTATIVE;
1995 /* Do we need a delay in this case? */
1996 nd6_dad_start((struct ifaddr *)ifa, 0);
1997 }
1998 }
1999 }
2000 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
2001 ND6_RUNLOCK();
2002 ND6_ONLINK_UNLOCK();
2003 }
2004
2005 /*
2006 * Add or remove interface route specified by @dst, @netmask and @ifp.
2007 * ifa can be NULL.
2008 * Returns 0 on success
2009 */
2010 static int
nd6_prefix_rtrequest(uint32_t fibnum,int cmd,struct sockaddr_in6 * dst,struct sockaddr_in6 * netmask,struct ifnet * ifp,struct ifaddr * ifa)2011 nd6_prefix_rtrequest(uint32_t fibnum, int cmd, struct sockaddr_in6 *dst,
2012 struct sockaddr_in6 *netmask, struct ifnet *ifp, struct ifaddr *ifa)
2013 {
2014 struct epoch_tracker et;
2015 int error;
2016
2017 /* Prepare gateway */
2018 struct sockaddr_dl_short sdl = {
2019 .sdl_family = AF_LINK,
2020 .sdl_len = sizeof(struct sockaddr_dl_short),
2021 .sdl_type = ifp->if_type,
2022 .sdl_index = ifp->if_index,
2023 };
2024
2025 struct rt_addrinfo info = {
2026 .rti_ifa = ifa,
2027 .rti_ifp = ifp,
2028 .rti_flags = RTF_PINNED | ((netmask != NULL) ? 0 : RTF_HOST),
2029 .rti_info = {
2030 [RTAX_DST] = (struct sockaddr *)dst,
2031 [RTAX_NETMASK] = (struct sockaddr *)netmask,
2032 [RTAX_GATEWAY] = (struct sockaddr *)&sdl,
2033 },
2034 };
2035 /* Don't set additional per-gw filters on removal */
2036
2037 NET_EPOCH_ENTER(et);
2038 error = rib_handle_ifaddr_info(fibnum, cmd, &info);
2039 NET_EPOCH_EXIT(et);
2040 return (error);
2041 }
2042
2043 static int
nd6_prefix_onlink_rtrequest(struct nd_prefix * pr,struct ifaddr * ifa)2044 nd6_prefix_onlink_rtrequest(struct nd_prefix *pr, struct ifaddr *ifa)
2045 {
2046 int error;
2047
2048 struct sockaddr_in6 mask6 = {
2049 .sin6_family = AF_INET6,
2050 .sin6_len = sizeof(struct sockaddr_in6),
2051 .sin6_addr = pr->ndpr_mask,
2052 };
2053 struct sockaddr_in6 *pmask6 = (pr->ndpr_plen != 128) ? &mask6 : NULL;
2054
2055 error = nd6_prefix_rtrequest(pr->ndpr_ifp->if_fib, RTM_ADD,
2056 &pr->ndpr_prefix, pmask6, pr->ndpr_ifp, ifa);
2057 if (error == 0)
2058 pr->ndpr_stateflags |= NDPRF_ONLINK;
2059
2060 return (error);
2061 }
2062
2063 static int
nd6_prefix_onlink(struct nd_prefix * pr)2064 nd6_prefix_onlink(struct nd_prefix *pr)
2065 {
2066 struct epoch_tracker et;
2067 struct ifaddr *ifa;
2068 struct ifnet *ifp = pr->ndpr_ifp;
2069 struct nd_prefix *opr;
2070 char ip6buf[INET6_ADDRSTRLEN];
2071 int error;
2072
2073 ND6_ONLINK_LOCK_ASSERT();
2074 ND6_UNLOCK_ASSERT();
2075
2076 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0)
2077 return (EEXIST);
2078
2079 /*
2080 * Add the interface route associated with the prefix. Before
2081 * installing the route, check if there's the same prefix on another
2082 * interface, and the prefix has already installed the interface route.
2083 * Although such a configuration is expected to be rare, we explicitly
2084 * allow it.
2085 */
2086 ND6_RLOCK();
2087 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) {
2088 if (opr == pr)
2089 continue;
2090
2091 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0)
2092 continue;
2093
2094 if (!V_rt_add_addr_allfibs &&
2095 opr->ndpr_ifp->if_fib != pr->ndpr_ifp->if_fib)
2096 continue;
2097
2098 if (opr->ndpr_plen == pr->ndpr_plen &&
2099 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
2100 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) {
2101 ND6_RUNLOCK();
2102 return (0);
2103 }
2104 }
2105 ND6_RUNLOCK();
2106
2107 /*
2108 * We prefer link-local addresses as the associated interface address.
2109 */
2110 /* search for a link-local addr */
2111 NET_EPOCH_ENTER(et);
2112 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
2113 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST);
2114 if (ifa == NULL) {
2115 /* XXX: freebsd does not have ifa_ifwithaf */
2116 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
2117 if (ifa->ifa_addr->sa_family == AF_INET6) {
2118 ifa_ref(ifa);
2119 break;
2120 }
2121 }
2122 /* should we care about ia6_flags? */
2123 }
2124 if (ifa == NULL) {
2125 /*
2126 * This can still happen, when, for example, we receive an RA
2127 * containing a prefix with the L bit set and the A bit clear,
2128 * after removing all IPv6 addresses on the receiving
2129 * interface. This should, of course, be rare though.
2130 */
2131 nd6log((LOG_NOTICE,
2132 "%s: failed to find any ifaddr to add route for a "
2133 "prefix(%s/%d) on %s\n", __func__,
2134 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
2135 pr->ndpr_plen, if_name(ifp)));
2136 error = 0;
2137 } else {
2138 error = nd6_prefix_onlink_rtrequest(pr, ifa);
2139 ifa_free(ifa);
2140 }
2141 NET_EPOCH_EXIT(et);
2142
2143 return (error);
2144 }
2145
2146 int
nd6_prefix_offlink(struct nd_prefix * pr)2147 nd6_prefix_offlink(struct nd_prefix *pr)
2148 {
2149 int error = 0;
2150 struct ifnet *ifp = pr->ndpr_ifp;
2151 struct nd_prefix *opr;
2152 char ip6buf[INET6_ADDRSTRLEN];
2153 uint64_t genid;
2154 int a_failure;
2155
2156 ND6_ONLINK_LOCK_ASSERT();
2157 ND6_UNLOCK_ASSERT();
2158
2159 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0)
2160 return (EEXIST);
2161
2162 struct sockaddr_in6 mask6 = {
2163 .sin6_family = AF_INET6,
2164 .sin6_len = sizeof(struct sockaddr_in6),
2165 .sin6_addr = pr->ndpr_mask,
2166 };
2167 struct sockaddr_in6 *pmask6 = (pr->ndpr_plen != 128) ? &mask6 : NULL;
2168
2169 error = nd6_prefix_rtrequest(ifp->if_fib, RTM_DELETE,
2170 &pr->ndpr_prefix, pmask6, ifp, NULL);
2171
2172 a_failure = 1;
2173 if (error == 0) {
2174 pr->ndpr_stateflags &= ~NDPRF_ONLINK;
2175
2176 /*
2177 * There might be the same prefix on another interface,
2178 * the prefix which could not be on-link just because we have
2179 * the interface route (see comments in nd6_prefix_onlink).
2180 * If there's one, try to make the prefix on-link on the
2181 * interface.
2182 */
2183 ND6_RLOCK();
2184 restart:
2185 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) {
2186 /*
2187 * KAME specific: detached prefixes should not be
2188 * on-link.
2189 */
2190 if (opr == pr || (opr->ndpr_stateflags &
2191 (NDPRF_ONLINK | NDPRF_DETACHED)) != 0)
2192 continue;
2193
2194 if (opr->ndpr_plen == pr->ndpr_plen &&
2195 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
2196 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) {
2197 int e;
2198
2199 genid = V_nd6_list_genid;
2200 ND6_RUNLOCK();
2201 if ((e = nd6_prefix_onlink(opr)) != 0) {
2202 nd6log((LOG_ERR,
2203 "%s: failed to recover a prefix "
2204 "%s/%d from %s to %s (errno=%d)\n",
2205 __func__, ip6_sprintf(ip6buf,
2206 &opr->ndpr_prefix.sin6_addr),
2207 opr->ndpr_plen, if_name(ifp),
2208 if_name(opr->ndpr_ifp), e));
2209 } else
2210 a_failure = 0;
2211 ND6_RLOCK();
2212 if (genid != V_nd6_list_genid)
2213 goto restart;
2214 }
2215 }
2216 ND6_RUNLOCK();
2217 } else {
2218 /* XXX: can we still set the NDPRF_ONLINK flag? */
2219 nd6log((LOG_ERR,
2220 "%s: failed to delete route: %s/%d on %s (errno=%d)\n",
2221 __func__, ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
2222 pr->ndpr_plen, if_name(ifp), error));
2223 }
2224
2225 if (a_failure)
2226 lltable_prefix_free(AF_INET6,
2227 (struct sockaddr *)&pr->ndpr_prefix,
2228 (struct sockaddr *)&mask6, LLE_STATIC);
2229
2230 return (error);
2231 }
2232
2233 /*
2234 * ia0 - corresponding public address
2235 */
2236 int
in6_tmpifadd(const struct in6_ifaddr * ia0,int forcegen,int delay)2237 in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay)
2238 {
2239 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp;
2240 struct in6_ifaddr *newia;
2241 struct in6_aliasreq ifra;
2242 int error;
2243 int trylimit = 3; /* XXX: adhoc value */
2244 int updateflags;
2245 u_int32_t randid[2];
2246 time_t vltime0, pltime0;
2247
2248 in6_prepare_ifra(&ifra, &ia0->ia_addr.sin6_addr,
2249 &ia0->ia_prefixmask.sin6_addr);
2250
2251 ifra.ifra_addr = ia0->ia_addr; /* XXX: do we need this ? */
2252 /* clear the old IFID */
2253 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr,
2254 &ifra.ifra_prefixmask.sin6_addr);
2255
2256 again:
2257 if (in6_get_tmpifid(ifp, (u_int8_t *)randid,
2258 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) {
2259 nd6log((LOG_NOTICE, "%s: failed to find a good random IFID\n",
2260 __func__));
2261 return (EINVAL);
2262 }
2263 ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
2264 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2]));
2265 ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
2266 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3]));
2267
2268 /*
2269 * in6_get_tmpifid() quite likely provided a unique interface ID.
2270 * However, we may still have a chance to see collision, because
2271 * there may be a time lag between generation of the ID and generation
2272 * of the address. So, we'll do one more sanity check.
2273 */
2274
2275 if (in6_localip(&ifra.ifra_addr.sin6_addr) != 0) {
2276 if (trylimit-- > 0) {
2277 forcegen = 1;
2278 goto again;
2279 }
2280
2281 /* Give up. Something strange should have happened. */
2282 nd6log((LOG_NOTICE, "%s: failed to find a unique random IFID\n",
2283 __func__));
2284 return (EEXIST);
2285 }
2286
2287 /*
2288 * The Valid Lifetime is the lower of the Valid Lifetime of the
2289 * public address or TEMP_VALID_LIFETIME.
2290 * The Preferred Lifetime is the lower of the Preferred Lifetime
2291 * of the public address or TEMP_PREFERRED_LIFETIME -
2292 * DESYNC_FACTOR.
2293 */
2294 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
2295 vltime0 = IFA6_IS_INVALID(ia0) ? 0 :
2296 (ia0->ia6_lifetime.ia6t_vltime -
2297 (time_uptime - ia0->ia6_updatetime));
2298 if (vltime0 > V_ip6_temp_valid_lifetime)
2299 vltime0 = V_ip6_temp_valid_lifetime;
2300 } else
2301 vltime0 = V_ip6_temp_valid_lifetime;
2302 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
2303 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 :
2304 (ia0->ia6_lifetime.ia6t_pltime -
2305 (time_uptime - ia0->ia6_updatetime));
2306 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){
2307 pltime0 = V_ip6_temp_preferred_lifetime -
2308 V_ip6_desync_factor;
2309 }
2310 } else
2311 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor;
2312 ifra.ifra_lifetime.ia6t_vltime = vltime0;
2313 ifra.ifra_lifetime.ia6t_pltime = pltime0;
2314
2315 /*
2316 * A temporary address is created only if this calculated Preferred
2317 * Lifetime is greater than REGEN_ADVANCE time units.
2318 */
2319 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance)
2320 return (0);
2321
2322 /* XXX: scope zone ID? */
2323
2324 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY);
2325
2326 /* allocate ifaddr structure, link into chain, etc. */
2327 updateflags = 0;
2328 if (delay)
2329 updateflags |= IN6_IFAUPDATE_DADDELAY;
2330 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0)
2331 return (error);
2332
2333 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
2334 if (newia == NULL) { /* XXX: can it happen? */
2335 nd6log((LOG_ERR,
2336 "%s: ifa update succeeded, but we got no ifaddr\n",
2337 __func__));
2338 return (EINVAL); /* XXX */
2339 }
2340 newia->ia6_ndpr = ia0->ia6_ndpr;
2341 newia->ia6_ndpr->ndpr_addrcnt++;
2342 ifa_free(&newia->ia_ifa);
2343
2344 /*
2345 * A newly added address might affect the status of other addresses.
2346 * XXX: when the temporary address is generated with a new public
2347 * address, the onlink check is redundant. However, it would be safe
2348 * to do the check explicitly everywhere a new address is generated,
2349 * and, in fact, we surely need the check when we create a new
2350 * temporary address due to deprecation of an old temporary address.
2351 */
2352 pfxlist_onlink_check();
2353
2354 return (0);
2355 }
2356
2357 static int
rt6_deleteroute(const struct rtentry * rt,const struct nhop_object * nh,void * arg)2358 rt6_deleteroute(const struct rtentry *rt, const struct nhop_object *nh,
2359 void *arg)
2360 {
2361 struct in6_addr *gate = (struct in6_addr *)arg;
2362 int nh_rt_flags;
2363
2364 if (nh->gw_sa.sa_family != AF_INET6)
2365 return (0);
2366
2367 if (!IN6_ARE_ADDR_EQUAL(gate, &nh->gw6_sa.sin6_addr)) {
2368 return (0);
2369 }
2370
2371 /*
2372 * Do not delete a static route.
2373 * XXX: this seems to be a bit ad-hoc. Should we consider the
2374 * 'cloned' bit instead?
2375 */
2376 nh_rt_flags = nhop_get_rtflags(nh);
2377 if ((nh_rt_flags & RTF_STATIC) != 0)
2378 return (0);
2379
2380 /*
2381 * We delete only host route. This means, in particular, we don't
2382 * delete default route.
2383 */
2384 if ((nh_rt_flags & RTF_HOST) == 0)
2385 return (0);
2386
2387 return (1);
2388 #undef SIN6
2389 }
2390
2391 /*
2392 * Delete all the routing table entries that use the specified gateway.
2393 * XXX: this function causes search through all entries of routing table, so
2394 * it shouldn't be called when acting as a router.
2395 */
2396 void
rt6_flush(struct in6_addr * gateway,struct ifnet * ifp)2397 rt6_flush(struct in6_addr *gateway, struct ifnet *ifp)
2398 {
2399
2400 /* We'll care only link-local addresses */
2401 if (!IN6_IS_ADDR_LINKLOCAL(gateway))
2402 return;
2403
2404 /* XXX Do we really need to walk any but the default FIB? */
2405 rib_foreach_table_walk_del(AF_INET6, rt6_deleteroute, (void *)gateway);
2406 }
2407
2408 int
nd6_setdefaultiface(int ifindex)2409 nd6_setdefaultiface(int ifindex)
2410 {
2411
2412 if (V_nd6_defifindex != ifindex) {
2413 V_nd6_defifindex = ifindex;
2414 if (V_nd6_defifindex != 0) {
2415 struct epoch_tracker et;
2416
2417 /*
2418 * XXXGL: this function should use ifnet_byindex_ref!
2419 */
2420 NET_EPOCH_ENTER(et);
2421 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex);
2422 NET_EPOCH_EXIT(et);
2423 if (V_nd6_defifp == NULL)
2424 return (EINVAL);
2425 } else
2426 V_nd6_defifp = NULL;
2427
2428 /*
2429 * Our current implementation assumes one-to-one mapping between
2430 * interfaces and links, so it would be natural to use the
2431 * default interface as the default link.
2432 */
2433 scope6_setdefault(V_nd6_defifp);
2434 }
2435
2436 return (0);
2437 }
2438
2439 bool
nd6_defrouter_list_empty(void)2440 nd6_defrouter_list_empty(void)
2441 {
2442
2443 return (TAILQ_EMPTY(&V_nd6_defrouter));
2444 }
2445
2446 void
nd6_defrouter_timer(void)2447 nd6_defrouter_timer(void)
2448 {
2449 struct nd_defrouter *dr, *ndr;
2450 struct nd6_drhead drq;
2451
2452 TAILQ_INIT(&drq);
2453
2454 ND6_WLOCK();
2455 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr)
2456 if (dr->expire && dr->expire < time_uptime)
2457 defrouter_unlink(dr, &drq);
2458 ND6_WUNLOCK();
2459
2460 while ((dr = TAILQ_FIRST(&drq)) != NULL) {
2461 TAILQ_REMOVE(&drq, dr, dr_entry);
2462 defrouter_del(dr);
2463 }
2464 }
2465
2466 /*
2467 * Nuke default router list entries toward ifp.
2468 * We defer removal of default router list entries that is installed in the
2469 * routing table, in order to keep additional side effects as small as possible.
2470 */
2471 void
nd6_defrouter_purge(struct ifnet * ifp)2472 nd6_defrouter_purge(struct ifnet *ifp)
2473 {
2474 struct nd_defrouter *dr, *ndr;
2475 struct nd6_drhead drq;
2476
2477 TAILQ_INIT(&drq);
2478
2479 ND6_WLOCK();
2480 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) {
2481 if (dr->installed)
2482 continue;
2483 if (dr->ifp == ifp)
2484 defrouter_unlink(dr, &drq);
2485 }
2486 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) {
2487 if (!dr->installed)
2488 continue;
2489 if (dr->ifp == ifp)
2490 defrouter_unlink(dr, &drq);
2491 }
2492 ND6_WUNLOCK();
2493
2494 /* Delete the unlinked router objects. */
2495 while ((dr = TAILQ_FIRST(&drq)) != NULL) {
2496 TAILQ_REMOVE(&drq, dr, dr_entry);
2497 defrouter_del(dr);
2498 }
2499 }
2500
2501 void
nd6_defrouter_flush_all(void)2502 nd6_defrouter_flush_all(void)
2503 {
2504 struct nd_defrouter *dr;
2505 struct nd6_drhead drq;
2506
2507 TAILQ_INIT(&drq);
2508
2509 ND6_WLOCK();
2510 while ((dr = TAILQ_FIRST(&V_nd6_defrouter)) != NULL)
2511 defrouter_unlink(dr, &drq);
2512 ND6_WUNLOCK();
2513
2514 while ((dr = TAILQ_FIRST(&drq)) != NULL) {
2515 TAILQ_REMOVE(&drq, dr, dr_entry);
2516 defrouter_del(dr);
2517 }
2518 }
2519
2520 void
nd6_defrouter_init(void)2521 nd6_defrouter_init(void)
2522 {
2523
2524 TAILQ_INIT(&V_nd6_defrouter);
2525 }
2526
2527 static int
nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)2528 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2529 {
2530 struct in6_defrouter d;
2531 struct nd_defrouter *dr;
2532 int error;
2533
2534 if (req->newptr != NULL)
2535 return (EPERM);
2536
2537 error = sysctl_wire_old_buffer(req, 0);
2538 if (error != 0)
2539 return (error);
2540
2541 bzero(&d, sizeof(d));
2542 d.rtaddr.sin6_family = AF_INET6;
2543 d.rtaddr.sin6_len = sizeof(d.rtaddr);
2544
2545 ND6_RLOCK();
2546 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) {
2547 d.rtaddr.sin6_addr = dr->rtaddr;
2548 error = sa6_recoverscope(&d.rtaddr);
2549 if (error != 0)
2550 break;
2551 d.flags = dr->raflags;
2552 d.rtlifetime = dr->rtlifetime;
2553 d.expire = dr->expire + (time_second - time_uptime);
2554 d.if_index = dr->ifp->if_index;
2555 error = SYSCTL_OUT(req, &d, sizeof(d));
2556 if (error != 0)
2557 break;
2558 }
2559 ND6_RUNLOCK();
2560 return (error);
2561 }
2562 SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2563 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE,
2564 NULL, 0, nd6_sysctl_drlist, "S,in6_defrouter",
2565 "NDP default router list");
2566