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_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD: releng/11.1/sys/netinet6/nd6_rtr.c 317067 2017-04-17 20:13:20Z asomers $");
34
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/syslog.h>
52 #include <sys/queue.h>
53
54 #include <net/if.h>
55 #include <net/if_var.h>
56 #include <net/if_types.h>
57 #include <net/if_dl.h>
58 #include <net/route.h>
59 #include <net/route_var.h>
60 #include <net/radix.h>
61 #include <net/vnet.h>
62
63 #include <netinet/in.h>
64 #include <net/if_llatbl.h>
65 #include <netinet6/in6_var.h>
66 #include <netinet6/in6_ifattach.h>
67 #include <netinet/ip6.h>
68 #include <netinet6/ip6_var.h>
69 #include <netinet6/nd6.h>
70 #include <netinet/icmp6.h>
71 #include <netinet6/scope6_var.h>
72
73 static int rtpref(struct nd_defrouter *);
74 static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *);
75 static int prelist_update(struct nd_prefixctl *, struct nd_defrouter *,
76 struct mbuf *, int);
77 static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int);
78 static struct nd_pfxrouter *pfxrtr_lookup(struct nd_prefix *,
79 struct nd_defrouter *);
80 static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *);
81 static void pfxrtr_del(struct nd_pfxrouter *);
82 static struct nd_pfxrouter *find_pfxlist_reachable_router(struct nd_prefix *);
83 static void defrouter_delreq(struct nd_defrouter *);
84 static void nd6_rtmsg(int, struct rtentry *);
85
86 static int in6_init_prefix_ltimes(struct nd_prefix *);
87 static void in6_init_address_ltimes(struct nd_prefix *,
88 struct in6_addrlifetime *);
89
90 static int rt6_deleteroute(const struct rtentry *, void *);
91
92 VNET_DECLARE(int, nd6_recalc_reachtm_interval);
93 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval)
94
95 static VNET_DEFINE(struct ifnet *, nd6_defifp);
96 VNET_DEFINE(int, nd6_defifindex);
97 #define V_nd6_defifp VNET(nd6_defifp)
98
99 VNET_DEFINE(int, ip6_use_tempaddr) = 0;
100
101 VNET_DEFINE(int, ip6_desync_factor);
102 VNET_DEFINE(u_int32_t, ip6_temp_preferred_lifetime) = DEF_TEMP_PREFERRED_LIFETIME;
103 VNET_DEFINE(u_int32_t, ip6_temp_valid_lifetime) = DEF_TEMP_VALID_LIFETIME;
104
105 VNET_DEFINE(int, ip6_temp_regen_advance) = TEMPADDR_REGEN_ADVANCE;
106
107 /* RTPREF_MEDIUM has to be 0! */
108 #define RTPREF_HIGH 1
109 #define RTPREF_MEDIUM 0
110 #define RTPREF_LOW (-1)
111 #define RTPREF_RESERVED (-2)
112 #define RTPREF_INVALID (-3) /* internal */
113
114 /*
115 * Receive Router Solicitation Message - just for routers.
116 * Router solicitation/advertisement is mostly managed by userland program
117 * (rtadvd) so here we have no function like nd6_ra_output().
118 *
119 * Based on RFC 2461
120 */
121 void
122 nd6_rs_input(struct mbuf *m, int off, int icmp6len)
123 {
124 struct ifnet *ifp = m->m_pkthdr.rcvif;
125 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
126 struct nd_router_solicit *nd_rs;
127 struct in6_addr saddr6 = ip6->ip6_src;
128 char *lladdr = NULL;
129 int lladdrlen = 0;
130 union nd_opts ndopts;
131 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
132
133 /*
134 * Accept RS only when V_ip6_forwarding=1 and the interface has
135 * no ND6_IFF_ACCEPT_RTADV.
136 */
137 if (!V_ip6_forwarding || ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV)
138 goto freeit;
139
140 /* Sanity checks */
141 if (ip6->ip6_hlim != 255) {
142 nd6log((LOG_ERR,
143 "nd6_rs_input: invalid hlim (%d) from %s to %s on %s\n",
144 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
145 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
146 goto bad;
147 }
148
149 /*
150 * Don't update the neighbor cache, if src = ::.
151 * This indicates that the src has no IP address assigned yet.
152 */
153 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
154 goto freeit;
155
156 #ifndef PULLDOWN_TEST
157 IP6_EXTHDR_CHECK(m, off, icmp6len,);
158 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off);
159 #else
160 IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len);
161 if (nd_rs == NULL) {
162 ICMP6STAT_INC(icp6s_tooshort);
163 return;
164 }
165 #endif
166
167 icmp6len -= sizeof(*nd_rs);
168 nd6_option_init(nd_rs + 1, icmp6len, &ndopts);
169 if (nd6_options(&ndopts) < 0) {
170 nd6log((LOG_INFO,
171 "nd6_rs_input: invalid ND option, ignored\n"));
172 /* nd6_options have incremented stats */
173 goto freeit;
174 }
175
176 if (ndopts.nd_opts_src_lladdr) {
177 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
178 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
179 }
180
181 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
182 nd6log((LOG_INFO,
183 "nd6_rs_input: lladdrlen mismatch for %s "
184 "(if %d, RS packet %d)\n",
185 ip6_sprintf(ip6bufs, &saddr6),
186 ifp->if_addrlen, lladdrlen - 2));
187 goto bad;
188 }
189
190 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0);
191
192 freeit:
193 m_freem(m);
194 return;
195
196 bad:
197 ICMP6STAT_INC(icp6s_badrs);
198 m_freem(m);
199 }
200
201 /*
202 * Receive Router Advertisement Message.
203 *
204 * Based on RFC 2461
205 * TODO: on-link bit on prefix information
206 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing
207 */
208 void
209 nd6_ra_input(struct mbuf *m, int off, int icmp6len)
210 {
211 struct ifnet *ifp = m->m_pkthdr.rcvif;
212 struct nd_ifinfo *ndi = ND_IFINFO(ifp);
213 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
214 struct nd_router_advert *nd_ra;
215 struct in6_addr saddr6 = ip6->ip6_src;
216 int mcast = 0;
217 union nd_opts ndopts;
218 struct nd_defrouter *dr;
219 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
220
221 dr = NULL;
222
223 /*
224 * We only accept RAs only when the per-interface flag
225 * ND6_IFF_ACCEPT_RTADV is on the receiving interface.
226 */
227 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV))
228 goto freeit;
229
230 if (ip6->ip6_hlim != 255) {
231 nd6log((LOG_ERR,
232 "nd6_ra_input: invalid hlim (%d) from %s to %s on %s\n",
233 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
234 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
235 goto bad;
236 }
237
238 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) {
239 nd6log((LOG_ERR,
240 "nd6_ra_input: src %s is not link-local\n",
241 ip6_sprintf(ip6bufs, &saddr6)));
242 goto bad;
243 }
244
245 #ifndef PULLDOWN_TEST
246 IP6_EXTHDR_CHECK(m, off, icmp6len,);
247 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off);
248 #else
249 IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len);
250 if (nd_ra == NULL) {
251 ICMP6STAT_INC(icp6s_tooshort);
252 return;
253 }
254 #endif
255
256 icmp6len -= sizeof(*nd_ra);
257 nd6_option_init(nd_ra + 1, icmp6len, &ndopts);
258 if (nd6_options(&ndopts) < 0) {
259 nd6log((LOG_INFO,
260 "nd6_ra_input: invalid ND option, ignored\n"));
261 /* nd6_options have incremented stats */
262 goto freeit;
263 }
264
265 {
266 struct nd_defrouter dr0;
267 u_int32_t advreachable = nd_ra->nd_ra_reachable;
268
269 /* remember if this is a multicasted advertisement */
270 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst))
271 mcast = 1;
272
273 bzero(&dr0, sizeof(dr0));
274 dr0.rtaddr = saddr6;
275 dr0.raflags = nd_ra->nd_ra_flags_reserved;
276 /*
277 * Effectively-disable routes from RA messages when
278 * ND6_IFF_NO_RADR enabled on the receiving interface or
279 * (ip6.forwarding == 1 && ip6.rfc6204w3 != 1).
280 */
281 if (ndi->flags & ND6_IFF_NO_RADR)
282 dr0.rtlifetime = 0;
283 else if (V_ip6_forwarding && !V_ip6_rfc6204w3)
284 dr0.rtlifetime = 0;
285 else
286 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime);
287 dr0.expire = time_uptime + dr0.rtlifetime;
288 dr0.ifp = ifp;
289 /* unspecified or not? (RFC 2461 6.3.4) */
290 if (advreachable) {
291 advreachable = ntohl(advreachable);
292 if (advreachable <= MAX_REACHABLE_TIME &&
293 ndi->basereachable != advreachable) {
294 ndi->basereachable = advreachable;
295 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable);
296 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */
297 }
298 }
299 if (nd_ra->nd_ra_retransmit)
300 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit);
301 if (nd_ra->nd_ra_curhoplimit) {
302 if (ndi->chlim < nd_ra->nd_ra_curhoplimit)
303 ndi->chlim = nd_ra->nd_ra_curhoplimit;
304 else if (ndi->chlim != nd_ra->nd_ra_curhoplimit) {
305 log(LOG_ERR, "RA with a lower CurHopLimit sent from "
306 "%s on %s (current = %d, received = %d). "
307 "Ignored.\n", ip6_sprintf(ip6bufs, &ip6->ip6_src),
308 if_name(ifp), ndi->chlim, nd_ra->nd_ra_curhoplimit);
309 }
310 }
311 dr = defrtrlist_update(&dr0);
312 }
313
314 /*
315 * prefix
316 */
317 if (ndopts.nd_opts_pi) {
318 struct nd_opt_hdr *pt;
319 struct nd_opt_prefix_info *pi = NULL;
320 struct nd_prefixctl pr;
321
322 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi;
323 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end;
324 pt = (struct nd_opt_hdr *)((caddr_t)pt +
325 (pt->nd_opt_len << 3))) {
326 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION)
327 continue;
328 pi = (struct nd_opt_prefix_info *)pt;
329
330 if (pi->nd_opt_pi_len != 4) {
331 nd6log((LOG_INFO,
332 "nd6_ra_input: invalid option "
333 "len %d for prefix information option, "
334 "ignored\n", pi->nd_opt_pi_len));
335 continue;
336 }
337
338 if (128 < pi->nd_opt_pi_prefix_len) {
339 nd6log((LOG_INFO,
340 "nd6_ra_input: invalid prefix "
341 "len %d for prefix information option, "
342 "ignored\n", pi->nd_opt_pi_prefix_len));
343 continue;
344 }
345
346 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix)
347 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) {
348 nd6log((LOG_INFO,
349 "nd6_ra_input: invalid prefix "
350 "%s, ignored\n",
351 ip6_sprintf(ip6bufs,
352 &pi->nd_opt_pi_prefix)));
353 continue;
354 }
355
356 bzero(&pr, sizeof(pr));
357 pr.ndpr_prefix.sin6_family = AF_INET6;
358 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix);
359 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix;
360 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif;
361
362 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved &
363 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0;
364 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved &
365 ND_OPT_PI_FLAG_AUTO) ? 1 : 0;
366 pr.ndpr_plen = pi->nd_opt_pi_prefix_len;
367 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time);
368 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time);
369 (void)prelist_update(&pr, dr, m, mcast);
370 }
371 }
372 if (dr != NULL) {
373 defrouter_rele(dr);
374 dr = NULL;
375 }
376
377 /*
378 * MTU
379 */
380 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) {
381 u_long mtu;
382 u_long maxmtu;
383
384 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
385
386 /* lower bound */
387 if (mtu < IPV6_MMTU) {
388 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option "
389 "mtu=%lu sent from %s, ignoring\n",
390 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src)));
391 goto skip;
392 }
393
394 /* upper bound */
395 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu)
396 ? ndi->maxmtu : ifp->if_mtu;
397 if (mtu <= maxmtu) {
398 int change = (ndi->linkmtu != mtu);
399
400 ndi->linkmtu = mtu;
401 if (change) /* in6_maxmtu may change */
402 in6_setmaxmtu();
403 } else {
404 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu "
405 "mtu=%lu sent from %s; "
406 "exceeds maxmtu %lu, ignoring\n",
407 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu));
408 }
409 }
410
411 skip:
412
413 /*
414 * Source link layer address
415 */
416 {
417 char *lladdr = NULL;
418 int lladdrlen = 0;
419
420 if (ndopts.nd_opts_src_lladdr) {
421 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
422 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
423 }
424
425 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
426 nd6log((LOG_INFO,
427 "nd6_ra_input: lladdrlen mismatch for %s "
428 "(if %d, RA packet %d)\n", ip6_sprintf(ip6bufs, &saddr6),
429 ifp->if_addrlen, lladdrlen - 2));
430 goto bad;
431 }
432
433 nd6_cache_lladdr(ifp, &saddr6, lladdr,
434 lladdrlen, ND_ROUTER_ADVERT, 0);
435
436 /*
437 * Installing a link-layer address might change the state of the
438 * router's neighbor cache, which might also affect our on-link
439 * detection of adveritsed prefixes.
440 */
441 pfxlist_onlink_check();
442 }
443
444 freeit:
445 m_freem(m);
446 return;
447
448 bad:
449 ICMP6STAT_INC(icp6s_badra);
450 m_freem(m);
451 }
452
453 /* tell the change to user processes watching the routing socket. */
454 static void
455 nd6_rtmsg(int cmd, struct rtentry *rt)
456 {
457 struct rt_addrinfo info;
458 struct ifnet *ifp;
459 struct ifaddr *ifa;
460
461 bzero((caddr_t)&info, sizeof(info));
462 info.rti_info[RTAX_DST] = rt_key(rt);
463 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
464 info.rti_info[RTAX_NETMASK] = rt_mask(rt);
465 ifp = rt->rt_ifp;
466 if (ifp != NULL) {
467 IF_ADDR_RLOCK(ifp);
468 ifa = TAILQ_FIRST(&ifp->if_addrhead);
469 info.rti_info[RTAX_IFP] = ifa->ifa_addr;
470 ifa_ref(ifa);
471 IF_ADDR_RUNLOCK(ifp);
472 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr;
473 } else
474 ifa = NULL;
475
476 rt_missmsg_fib(cmd, &info, rt->rt_flags, 0, rt->rt_fibnum);
477 if (ifa != NULL)
478 ifa_free(ifa);
479 }
480
481 /*
482 * default router list processing sub routines
483 */
484
485 static void
486 defrouter_addreq(struct nd_defrouter *new)
487 {
488 struct sockaddr_in6 def, mask, gate;
489 struct rtentry *newrt = NULL;
490 int error;
491
492 bzero(&def, sizeof(def));
493 bzero(&mask, sizeof(mask));
494 bzero(&gate, sizeof(gate));
495
496 def.sin6_len = mask.sin6_len = gate.sin6_len =
497 sizeof(struct sockaddr_in6);
498 def.sin6_family = gate.sin6_family = AF_INET6;
499 gate.sin6_addr = new->rtaddr;
500
501 error = in6_rtrequest(RTM_ADD, (struct sockaddr *)&def,
502 (struct sockaddr *)&gate, (struct sockaddr *)&mask,
503 RTF_GATEWAY, &newrt, new->ifp->if_fib);
504 if (newrt) {
505 nd6_rtmsg(RTM_ADD, newrt); /* tell user process */
506 RTFREE(newrt);
507 }
508 if (error == 0)
509 new->installed = 1;
510 }
511
512 struct nd_defrouter *
513 defrouter_lookup_locked(struct in6_addr *addr, struct ifnet *ifp)
514 {
515 struct nd_defrouter *dr;
516
517 ND6_LOCK_ASSERT();
518 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry)
519 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) {
520 defrouter_ref(dr);
521 return (dr);
522 }
523 return (NULL);
524 }
525
526 struct nd_defrouter *
527 defrouter_lookup(struct in6_addr *addr, struct ifnet *ifp)
528 {
529 struct nd_defrouter *dr;
530
531 ND6_RLOCK();
532 dr = defrouter_lookup_locked(addr, ifp);
533 ND6_RUNLOCK();
534 return (dr);
535 }
536
537 void
538 defrouter_ref(struct nd_defrouter *dr)
539 {
540
541 refcount_acquire(&dr->refcnt);
542 }
543
544 void
545 defrouter_rele(struct nd_defrouter *dr)
546 {
547
548 if (refcount_release(&dr->refcnt))
549 free(dr, M_IP6NDP);
550 }
551
552 /*
553 * Remove the default route for a given router.
554 * This is just a subroutine function for defrouter_select_fib(), and
555 * should not be called from anywhere else.
556 */
557 static void
558 defrouter_delreq(struct nd_defrouter *dr)
559 {
560 struct sockaddr_in6 def, mask, gate;
561 struct rtentry *oldrt = NULL;
562
563 bzero(&def, sizeof(def));
564 bzero(&mask, sizeof(mask));
565 bzero(&gate, sizeof(gate));
566
567 def.sin6_len = mask.sin6_len = gate.sin6_len =
568 sizeof(struct sockaddr_in6);
569 def.sin6_family = gate.sin6_family = AF_INET6;
570 gate.sin6_addr = dr->rtaddr;
571
572 in6_rtrequest(RTM_DELETE, (struct sockaddr *)&def,
573 (struct sockaddr *)&gate,
574 (struct sockaddr *)&mask, RTF_GATEWAY, &oldrt, dr->ifp->if_fib);
575 if (oldrt) {
576 nd6_rtmsg(RTM_DELETE, oldrt);
577 RTFREE(oldrt);
578 }
579
580 dr->installed = 0;
581 }
582
583 /*
584 * Remove all default routes from default router list.
585 */
586 void
587 defrouter_reset(void)
588 {
589 struct nd_defrouter *dr, **dra;
590 int count, i;
591
592 count = i = 0;
593
594 /*
595 * We can't delete routes with the ND lock held, so make a copy of the
596 * current default router list and use that when deleting routes.
597 */
598 ND6_RLOCK();
599 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry)
600 count++;
601 ND6_RUNLOCK();
602
603 dra = malloc(count * sizeof(*dra), M_TEMP, M_WAITOK | M_ZERO);
604
605 ND6_RLOCK();
606 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
607 if (i == count)
608 break;
609 defrouter_ref(dr);
610 dra[i++] = dr;
611 }
612 ND6_RUNLOCK();
613
614 for (i = 0; i < count && dra[i] != NULL; i++) {
615 defrouter_delreq(dra[i]);
616 defrouter_rele(dra[i]);
617 }
618 free(dra, M_TEMP);
619
620 /*
621 * XXX should we also nuke any default routers in the kernel, by
622 * going through them by rtalloc1()?
623 */
624 }
625
626 /*
627 * Look up a matching default router list entry and remove it. Returns true if a
628 * matching entry was found, false otherwise.
629 */
630 bool
631 defrouter_remove(struct in6_addr *addr, struct ifnet *ifp)
632 {
633 struct nd_defrouter *dr;
634
635 ND6_WLOCK();
636 dr = defrouter_lookup_locked(addr, ifp);
637 if (dr == NULL) {
638 ND6_WUNLOCK();
639 return (false);
640 }
641
642 defrouter_unlink(dr, NULL);
643 ND6_WUNLOCK();
644 defrouter_del(dr);
645 defrouter_rele(dr);
646 return (true);
647 }
648
649 /*
650 * Remove a router from the global list and optionally stash it in a
651 * caller-supplied queue.
652 *
653 * The ND lock must be held.
654 */
655 void
656 defrouter_unlink(struct nd_defrouter *dr, struct nd_drhead *drq)
657 {
658
659 ND6_WLOCK_ASSERT();
660 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry);
661 V_nd6_list_genid++;
662 if (drq != NULL)
663 TAILQ_INSERT_TAIL(drq, dr, dr_entry);
664 }
665
666 void
667 defrouter_del(struct nd_defrouter *dr)
668 {
669 struct nd_defrouter *deldr = NULL;
670 struct nd_prefix *pr;
671 struct nd_pfxrouter *pfxrtr;
672
673 ND6_UNLOCK_ASSERT();
674
675 /*
676 * Flush all the routing table entries that use the router
677 * as a next hop.
678 */
679 if (ND_IFINFO(dr->ifp)->flags & ND6_IFF_ACCEPT_RTADV)
680 rt6_flush(&dr->rtaddr, dr->ifp);
681
682 if (dr->installed) {
683 deldr = dr;
684 defrouter_delreq(dr);
685 }
686
687 /*
688 * Also delete all the pointers to the router in each prefix lists.
689 */
690 ND6_WLOCK();
691 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
692 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL)
693 pfxrtr_del(pfxrtr);
694 }
695 ND6_WUNLOCK();
696
697 pfxlist_onlink_check();
698
699 /*
700 * If the router is the primary one, choose a new one.
701 * Note that defrouter_select_fib() will remove the current
702 * gateway from the routing table.
703 */
704 if (deldr)
705 defrouter_select_fib(deldr->ifp->if_fib);
706
707 /*
708 * Release the list reference.
709 */
710 defrouter_rele(dr);
711 }
712
713 /*
714 * Default Router Selection according to Section 6.3.6 of RFC 2461 and
715 * draft-ietf-ipngwg-router-selection:
716 * 1) Routers that are reachable or probably reachable should be preferred.
717 * If we have more than one (probably) reachable router, prefer ones
718 * with the highest router preference.
719 * 2) When no routers on the list are known to be reachable or
720 * probably reachable, routers SHOULD be selected in a round-robin
721 * fashion, regardless of router preference values.
722 * 3) If the Default Router List is empty, assume that all
723 * destinations are on-link.
724 *
725 * We assume nd_defrouter is sorted by router preference value.
726 * Since the code below covers both with and without router preference cases,
727 * we do not need to classify the cases by ifdef.
728 *
729 * At this moment, we do not try to install more than one default router,
730 * even when the multipath routing is available, because we're not sure about
731 * the benefits for stub hosts comparing to the risk of making the code
732 * complicated and the possibility of introducing bugs.
733 *
734 * We maintain a single list of routers for multiple FIBs, only considering one
735 * at a time based on the receiving interface's FIB. If @fibnum is RT_ALL_FIBS,
736 * we do the whole thing multiple times.
737 */
738 void
739 defrouter_select_fib(int fibnum)
740 {
741 struct nd_defrouter *dr, *selected_dr, *installed_dr;
742 struct llentry *ln = NULL;
743
744 if (fibnum == RT_ALL_FIBS) {
745 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) {
746 defrouter_select_fib(fibnum);
747 }
748 }
749
750 ND6_RLOCK();
751 /*
752 * Let's handle easy case (3) first:
753 * If default router list is empty, there's nothing to be done.
754 */
755 if (TAILQ_EMPTY(&V_nd_defrouter)) {
756 ND6_RUNLOCK();
757 return;
758 }
759
760 /*
761 * Search for a (probably) reachable router from the list.
762 * We just pick up the first reachable one (if any), assuming that
763 * the ordering rule of the list described in defrtrlist_update().
764 */
765 selected_dr = installed_dr = NULL;
766 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
767 IF_AFDATA_RLOCK(dr->ifp);
768 if (selected_dr == NULL && dr->ifp->if_fib == fibnum &&
769 (ln = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) &&
770 ND6_IS_LLINFO_PROBREACH(ln)) {
771 selected_dr = dr;
772 defrouter_ref(selected_dr);
773 }
774 IF_AFDATA_RUNLOCK(dr->ifp);
775 if (ln != NULL) {
776 LLE_RUNLOCK(ln);
777 ln = NULL;
778 }
779
780 if (dr->installed && dr->ifp->if_fib == fibnum) {
781 if (installed_dr == NULL) {
782 installed_dr = dr;
783 defrouter_ref(installed_dr);
784 } else {
785 /*
786 * this should not happen.
787 * warn for diagnosis.
788 */
789 log(LOG_ERR, "defrouter_select_fib: more than "
790 "one router is installed\n");
791 }
792 }
793 }
794 /*
795 * If none of the default routers was found to be reachable,
796 * round-robin the list regardless of preference.
797 * Otherwise, if we have an installed router, check if the selected
798 * (reachable) router should really be preferred to the installed one.
799 * We only prefer the new router when the old one is not reachable
800 * or when the new one has a really higher preference value.
801 */
802 if (selected_dr == NULL) {
803 if (installed_dr == NULL ||
804 TAILQ_NEXT(installed_dr, dr_entry) == NULL)
805 dr = TAILQ_FIRST(&V_nd_defrouter);
806 else
807 dr = TAILQ_NEXT(installed_dr, dr_entry);
808
809 /* Ensure we select a router for this FIB. */
810 TAILQ_FOREACH_FROM(dr, &V_nd_defrouter, dr_entry) {
811 if (dr->ifp->if_fib == fibnum) {
812 selected_dr = dr;
813 defrouter_ref(selected_dr);
814 break;
815 }
816 }
817 } else if (installed_dr != NULL) {
818 IF_AFDATA_RLOCK(installed_dr->ifp);
819 if ((ln = nd6_lookup(&installed_dr->rtaddr, 0,
820 installed_dr->ifp)) &&
821 ND6_IS_LLINFO_PROBREACH(ln) &&
822 installed_dr->ifp->if_fib == fibnum &&
823 rtpref(selected_dr) <= rtpref(installed_dr)) {
824 defrouter_rele(selected_dr);
825 selected_dr = installed_dr;
826 }
827 IF_AFDATA_RUNLOCK(installed_dr->ifp);
828 if (ln != NULL)
829 LLE_RUNLOCK(ln);
830 }
831 ND6_RUNLOCK();
832
833 /*
834 * If we selected a router for this FIB and it's different
835 * than the installed one, remove the installed router and
836 * install the selected one in its place.
837 */
838 if (installed_dr != selected_dr) {
839 if (installed_dr != NULL) {
840 defrouter_delreq(installed_dr);
841 defrouter_rele(installed_dr);
842 }
843 if (selected_dr != NULL)
844 defrouter_addreq(selected_dr);
845 }
846 if (selected_dr != NULL)
847 defrouter_rele(selected_dr);
848 }
849
850 /*
851 * Maintain old KPI for default router selection.
852 * If unspecified, we can re-select routers for all FIBs.
853 */
854 void
855 defrouter_select(void)
856 {
857 defrouter_select_fib(RT_ALL_FIBS);
858 }
859
860 /*
861 * for default router selection
862 * regards router-preference field as a 2-bit signed integer
863 */
864 static int
865 rtpref(struct nd_defrouter *dr)
866 {
867 switch (dr->raflags & ND_RA_FLAG_RTPREF_MASK) {
868 case ND_RA_FLAG_RTPREF_HIGH:
869 return (RTPREF_HIGH);
870 case ND_RA_FLAG_RTPREF_MEDIUM:
871 case ND_RA_FLAG_RTPREF_RSV:
872 return (RTPREF_MEDIUM);
873 case ND_RA_FLAG_RTPREF_LOW:
874 return (RTPREF_LOW);
875 default:
876 /*
877 * This case should never happen. If it did, it would mean a
878 * serious bug of kernel internal. We thus always bark here.
879 * Or, can we even panic?
880 */
881 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->raflags);
882 return (RTPREF_INVALID);
883 }
884 /* NOTREACHED */
885 }
886
887 static struct nd_defrouter *
888 defrtrlist_update(struct nd_defrouter *new)
889 {
890 struct nd_defrouter *dr, *n;
891 uint64_t genid;
892 int oldpref;
893 bool writelocked;
894
895 if (new->rtlifetime == 0) {
896 defrouter_remove(&new->rtaddr, new->ifp);
897 return (NULL);
898 }
899
900 ND6_RLOCK();
901 writelocked = false;
902 restart:
903 dr = defrouter_lookup_locked(&new->rtaddr, new->ifp);
904 if (dr != NULL) {
905 oldpref = rtpref(dr);
906
907 /* override */
908 dr->raflags = new->raflags; /* XXX flag check */
909 dr->rtlifetime = new->rtlifetime;
910 dr->expire = new->expire;
911
912 /*
913 * If the preference does not change, there's no need
914 * to sort the entries. Also make sure the selected
915 * router is still installed in the kernel.
916 */
917 if (dr->installed && rtpref(new) == oldpref) {
918 if (writelocked)
919 ND6_WUNLOCK();
920 else
921 ND6_RUNLOCK();
922 return (dr);
923 }
924 }
925
926 /*
927 * The router needs to be reinserted into the default router
928 * list, so upgrade to a write lock. If that fails and the list
929 * has potentially changed while the lock was dropped, we'll
930 * redo the lookup with the write lock held.
931 */
932 if (!writelocked) {
933 writelocked = true;
934 if (!ND6_TRY_UPGRADE()) {
935 genid = V_nd6_list_genid;
936 ND6_RUNLOCK();
937 ND6_WLOCK();
938 if (genid != V_nd6_list_genid)
939 goto restart;
940 }
941 }
942
943 if (dr != NULL) {
944 /*
945 * The preferred router may have changed, so relocate this
946 * router.
947 */
948 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry);
949 n = dr;
950 } else {
951 n = malloc(sizeof(*n), M_IP6NDP, M_NOWAIT | M_ZERO);
952 if (n == NULL) {
953 ND6_WUNLOCK();
954 return (NULL);
955 }
956 memcpy(n, new, sizeof(*n));
957 /* Initialize with an extra reference for the caller. */
958 refcount_init(&n->refcnt, 2);
959 }
960
961 /*
962 * Insert the new router in the Default Router List;
963 * The Default Router List should be in the descending order
964 * of router-preferece. Routers with the same preference are
965 * sorted in the arriving time order.
966 */
967
968 /* insert at the end of the group */
969 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
970 if (rtpref(n) > rtpref(dr))
971 break;
972 }
973 if (dr != NULL)
974 TAILQ_INSERT_BEFORE(dr, n, dr_entry);
975 else
976 TAILQ_INSERT_TAIL(&V_nd_defrouter, n, dr_entry);
977 V_nd6_list_genid++;
978 ND6_WUNLOCK();
979
980 defrouter_select_fib(new->ifp->if_fib);
981
982 return (n);
983 }
984
985 static struct nd_pfxrouter *
986 pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr)
987 {
988 struct nd_pfxrouter *search;
989
990 ND6_LOCK_ASSERT();
991
992 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) {
993 if (search->router == dr)
994 break;
995 }
996 return (search);
997 }
998
999 static void
1000 pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr)
1001 {
1002 struct nd_pfxrouter *new;
1003 bool update;
1004
1005 ND6_UNLOCK_ASSERT();
1006
1007 ND6_RLOCK();
1008 if (pfxrtr_lookup(pr, dr) != NULL) {
1009 ND6_RUNLOCK();
1010 return;
1011 }
1012 ND6_RUNLOCK();
1013
1014 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO);
1015 if (new == NULL)
1016 return;
1017 defrouter_ref(dr);
1018 new->router = dr;
1019
1020 ND6_WLOCK();
1021 if (pfxrtr_lookup(pr, dr) == NULL) {
1022 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry);
1023 update = true;
1024 } else {
1025 /* We lost a race to add the reference. */
1026 defrouter_rele(dr);
1027 free(new, M_IP6NDP);
1028 update = false;
1029 }
1030 ND6_WUNLOCK();
1031
1032 if (update)
1033 pfxlist_onlink_check();
1034 }
1035
1036 static void
1037 pfxrtr_del(struct nd_pfxrouter *pfr)
1038 {
1039
1040 ND6_WLOCK_ASSERT();
1041
1042 LIST_REMOVE(pfr, pfr_entry);
1043 defrouter_rele(pfr->router);
1044 free(pfr, M_IP6NDP);
1045 }
1046
1047 static struct nd_prefix *
1048 nd6_prefix_lookup_locked(struct nd_prefixctl *key)
1049 {
1050 struct nd_prefix *search;
1051
1052 ND6_LOCK_ASSERT();
1053
1054 LIST_FOREACH(search, &V_nd_prefix, ndpr_entry) {
1055 if (key->ndpr_ifp == search->ndpr_ifp &&
1056 key->ndpr_plen == search->ndpr_plen &&
1057 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr,
1058 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) {
1059 nd6_prefix_ref(search);
1060 break;
1061 }
1062 }
1063 return (search);
1064 }
1065
1066 struct nd_prefix *
1067 nd6_prefix_lookup(struct nd_prefixctl *key)
1068 {
1069 struct nd_prefix *search;
1070
1071 ND6_RLOCK();
1072 search = nd6_prefix_lookup_locked(key);
1073 ND6_RUNLOCK();
1074 return (search);
1075 }
1076
1077 void
1078 nd6_prefix_ref(struct nd_prefix *pr)
1079 {
1080
1081 refcount_acquire(&pr->ndpr_refcnt);
1082 }
1083
1084 void
1085 nd6_prefix_rele(struct nd_prefix *pr)
1086 {
1087
1088 if (refcount_release(&pr->ndpr_refcnt)) {
1089 KASSERT(LIST_EMPTY(&pr->ndpr_advrtrs),
1090 ("prefix %p has advertising routers", pr));
1091 free(pr, M_IP6NDP);
1092 }
1093 }
1094
1095 int
1096 nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr,
1097 struct nd_prefix **newp)
1098 {
1099 struct nd_prefix *new;
1100 char ip6buf[INET6_ADDRSTRLEN];
1101 int error;
1102
1103 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO);
1104 if (new == NULL)
1105 return (ENOMEM);
1106 refcount_init(&new->ndpr_refcnt, newp != NULL ? 2 : 1);
1107 new->ndpr_ifp = pr->ndpr_ifp;
1108 new->ndpr_prefix = pr->ndpr_prefix;
1109 new->ndpr_plen = pr->ndpr_plen;
1110 new->ndpr_vltime = pr->ndpr_vltime;
1111 new->ndpr_pltime = pr->ndpr_pltime;
1112 new->ndpr_flags = pr->ndpr_flags;
1113 if ((error = in6_init_prefix_ltimes(new)) != 0) {
1114 free(new, M_IP6NDP);
1115 return (error);
1116 }
1117 new->ndpr_lastupdate = time_uptime;
1118
1119 /* initialization */
1120 LIST_INIT(&new->ndpr_advrtrs);
1121 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen);
1122 /* make prefix in the canonical form */
1123 IN6_MASK_ADDR(&new->ndpr_prefix.sin6_addr, &new->ndpr_mask);
1124
1125 ND6_WLOCK();
1126 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry);
1127 V_nd6_list_genid++;
1128 ND6_WUNLOCK();
1129
1130 /* ND_OPT_PI_FLAG_ONLINK processing */
1131 if (new->ndpr_raf_onlink) {
1132 ND6_ONLINK_LOCK();
1133 if ((error = nd6_prefix_onlink(new)) != 0) {
1134 nd6log((LOG_ERR, "nd6_prelist_add: failed to make "
1135 "the prefix %s/%d on-link on %s (errno=%d)\n",
1136 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
1137 pr->ndpr_plen, if_name(pr->ndpr_ifp), error));
1138 /* proceed anyway. XXX: is it correct? */
1139 }
1140 ND6_ONLINK_UNLOCK();
1141 }
1142
1143 if (dr != NULL)
1144 pfxrtr_add(new, dr);
1145 if (newp != NULL)
1146 *newp = new;
1147 return (0);
1148 }
1149
1150 /*
1151 * Remove a prefix from the prefix list and optionally stash it in a
1152 * caller-provided list.
1153 *
1154 * The ND6 lock must be held.
1155 */
1156 void
1157 nd6_prefix_unlink(struct nd_prefix *pr, struct nd_prhead *list)
1158 {
1159
1160 ND6_WLOCK_ASSERT();
1161
1162 LIST_REMOVE(pr, ndpr_entry);
1163 V_nd6_list_genid++;
1164 if (list != NULL)
1165 LIST_INSERT_HEAD(list, pr, ndpr_entry);
1166 }
1167
1168 /*
1169 * Free an unlinked prefix, first marking it off-link if necessary.
1170 */
1171 void
1172 nd6_prefix_del(struct nd_prefix *pr)
1173 {
1174 struct nd_pfxrouter *pfr, *next;
1175 int e;
1176 char ip6buf[INET6_ADDRSTRLEN];
1177
1178 KASSERT(pr->ndpr_addrcnt == 0,
1179 ("prefix %p has referencing addresses", pr));
1180 ND6_UNLOCK_ASSERT();
1181
1182 /*
1183 * Though these flags are now meaningless, we'd rather keep the value
1184 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users
1185 * when executing "ndp -p".
1186 */
1187 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
1188 ND6_ONLINK_LOCK();
1189 if ((e = nd6_prefix_offlink(pr)) != 0) {
1190 nd6log((LOG_ERR,
1191 "nd6_prefix_del: failed to make %s/%d offlink "
1192 "on %s, errno=%d\n",
1193 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
1194 pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
1195 /* what should we do? */
1196 }
1197 ND6_ONLINK_UNLOCK();
1198 }
1199
1200 /* Release references to routers that have advertised this prefix. */
1201 ND6_WLOCK();
1202 LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next)
1203 pfxrtr_del(pfr);
1204 ND6_WUNLOCK();
1205
1206 nd6_prefix_rele(pr);
1207
1208 pfxlist_onlink_check();
1209 }
1210
1211 static int
1212 prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr,
1213 struct mbuf *m, int mcast)
1214 {
1215 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL;
1216 struct ifaddr *ifa;
1217 struct ifnet *ifp = new->ndpr_ifp;
1218 struct nd_prefix *pr;
1219 int error = 0;
1220 int auth;
1221 struct in6_addrlifetime lt6_tmp;
1222 char ip6buf[INET6_ADDRSTRLEN];
1223
1224 auth = 0;
1225 if (m) {
1226 /*
1227 * Authenticity for NA consists authentication for
1228 * both IP header and IP datagrams, doesn't it ?
1229 */
1230 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM)
1231 auth = ((m->m_flags & M_AUTHIPHDR) &&
1232 (m->m_flags & M_AUTHIPDGM));
1233 #endif
1234 }
1235
1236 if ((pr = nd6_prefix_lookup(new)) != NULL) {
1237 /*
1238 * nd6_prefix_lookup() ensures that pr and new have the same
1239 * prefix on a same interface.
1240 */
1241
1242 /*
1243 * Update prefix information. Note that the on-link (L) bit
1244 * and the autonomous (A) bit should NOT be changed from 1
1245 * to 0.
1246 */
1247 if (new->ndpr_raf_onlink == 1)
1248 pr->ndpr_raf_onlink = 1;
1249 if (new->ndpr_raf_auto == 1)
1250 pr->ndpr_raf_auto = 1;
1251 if (new->ndpr_raf_onlink) {
1252 pr->ndpr_vltime = new->ndpr_vltime;
1253 pr->ndpr_pltime = new->ndpr_pltime;
1254 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */
1255 pr->ndpr_lastupdate = time_uptime;
1256 }
1257
1258 if (new->ndpr_raf_onlink &&
1259 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
1260 ND6_ONLINK_LOCK();
1261 if ((error = nd6_prefix_onlink(pr)) != 0) {
1262 nd6log((LOG_ERR,
1263 "prelist_update: failed to make "
1264 "the prefix %s/%d on-link on %s "
1265 "(errno=%d)\n",
1266 ip6_sprintf(ip6buf,
1267 &pr->ndpr_prefix.sin6_addr),
1268 pr->ndpr_plen, if_name(pr->ndpr_ifp),
1269 error));
1270 /* proceed anyway. XXX: is it correct? */
1271 }
1272 ND6_ONLINK_UNLOCK();
1273 }
1274
1275 if (dr != NULL)
1276 pfxrtr_add(pr, dr);
1277 } else {
1278 if (new->ndpr_vltime == 0)
1279 goto end;
1280 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0)
1281 goto end;
1282
1283 error = nd6_prelist_add(new, dr, &pr);
1284 if (error != 0) {
1285 nd6log((LOG_NOTICE, "prelist_update: "
1286 "nd6_prelist_add failed for %s/%d on %s errno=%d\n",
1287 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr),
1288 new->ndpr_plen, if_name(new->ndpr_ifp), error));
1289 goto end; /* we should just give up in this case. */
1290 }
1291
1292 /*
1293 * XXX: from the ND point of view, we can ignore a prefix
1294 * with the on-link bit being zero. However, we need a
1295 * prefix structure for references from autoconfigured
1296 * addresses. Thus, we explicitly make sure that the prefix
1297 * itself expires now.
1298 */
1299 if (pr->ndpr_raf_onlink == 0) {
1300 pr->ndpr_vltime = 0;
1301 pr->ndpr_pltime = 0;
1302 in6_init_prefix_ltimes(pr);
1303 }
1304 }
1305
1306 /*
1307 * Address autoconfiguration based on Section 5.5.3 of RFC 2462.
1308 * Note that pr must be non NULL at this point.
1309 */
1310
1311 /* 5.5.3 (a). Ignore the prefix without the A bit set. */
1312 if (!new->ndpr_raf_auto)
1313 goto end;
1314
1315 /*
1316 * 5.5.3 (b). the link-local prefix should have been ignored in
1317 * nd6_ra_input.
1318 */
1319
1320 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */
1321 if (new->ndpr_pltime > new->ndpr_vltime) {
1322 error = EINVAL; /* XXX: won't be used */
1323 goto end;
1324 }
1325
1326 /*
1327 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of
1328 * an address configured by stateless autoconfiguration already in the
1329 * list of addresses associated with the interface, and the Valid
1330 * Lifetime is not 0, form an address. We first check if we have
1331 * a matching prefix.
1332 * Note: we apply a clarification in rfc2462bis-02 here. We only
1333 * consider autoconfigured addresses while RFC2462 simply said
1334 * "address".
1335 */
1336 IF_ADDR_RLOCK(ifp);
1337 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1338 struct in6_ifaddr *ifa6;
1339 u_int32_t remaininglifetime;
1340
1341 if (ifa->ifa_addr->sa_family != AF_INET6)
1342 continue;
1343
1344 ifa6 = (struct in6_ifaddr *)ifa;
1345
1346 /*
1347 * We only consider autoconfigured addresses as per rfc2462bis.
1348 */
1349 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF))
1350 continue;
1351
1352 /*
1353 * Spec is not clear here, but I believe we should concentrate
1354 * on unicast (i.e. not anycast) addresses.
1355 * XXX: other ia6_flags? detached or duplicated?
1356 */
1357 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0)
1358 continue;
1359
1360 /*
1361 * Ignore the address if it is not associated with a prefix
1362 * or is associated with a prefix that is different from this
1363 * one. (pr is never NULL here)
1364 */
1365 if (ifa6->ia6_ndpr != pr)
1366 continue;
1367
1368 if (ia6_match == NULL) /* remember the first one */
1369 ia6_match = ifa6;
1370
1371 /*
1372 * An already autoconfigured address matched. Now that we
1373 * are sure there is at least one matched address, we can
1374 * proceed to 5.5.3. (e): update the lifetimes according to the
1375 * "two hours" rule and the privacy extension.
1376 * We apply some clarifications in rfc2462bis:
1377 * - use remaininglifetime instead of storedlifetime as a
1378 * variable name
1379 * - remove the dead code in the "two-hour" rule
1380 */
1381 #define TWOHOUR (120*60)
1382 lt6_tmp = ifa6->ia6_lifetime;
1383
1384 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME)
1385 remaininglifetime = ND6_INFINITE_LIFETIME;
1386 else if (time_uptime - ifa6->ia6_updatetime >
1387 lt6_tmp.ia6t_vltime) {
1388 /*
1389 * The case of "invalid" address. We should usually
1390 * not see this case.
1391 */
1392 remaininglifetime = 0;
1393 } else
1394 remaininglifetime = lt6_tmp.ia6t_vltime -
1395 (time_uptime - ifa6->ia6_updatetime);
1396
1397 /* when not updating, keep the current stored lifetime. */
1398 lt6_tmp.ia6t_vltime = remaininglifetime;
1399
1400 if (TWOHOUR < new->ndpr_vltime ||
1401 remaininglifetime < new->ndpr_vltime) {
1402 lt6_tmp.ia6t_vltime = new->ndpr_vltime;
1403 } else if (remaininglifetime <= TWOHOUR) {
1404 if (auth) {
1405 lt6_tmp.ia6t_vltime = new->ndpr_vltime;
1406 }
1407 } else {
1408 /*
1409 * new->ndpr_vltime <= TWOHOUR &&
1410 * TWOHOUR < remaininglifetime
1411 */
1412 lt6_tmp.ia6t_vltime = TWOHOUR;
1413 }
1414
1415 /* The 2 hour rule is not imposed for preferred lifetime. */
1416 lt6_tmp.ia6t_pltime = new->ndpr_pltime;
1417
1418 in6_init_address_ltimes(pr, <6_tmp);
1419
1420 /*
1421 * We need to treat lifetimes for temporary addresses
1422 * differently, according to
1423 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1);
1424 * we only update the lifetimes when they are in the maximum
1425 * intervals.
1426 */
1427 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
1428 u_int32_t maxvltime, maxpltime;
1429
1430 if (V_ip6_temp_valid_lifetime >
1431 (u_int32_t)((time_uptime - ifa6->ia6_createtime) +
1432 V_ip6_desync_factor)) {
1433 maxvltime = V_ip6_temp_valid_lifetime -
1434 (time_uptime - ifa6->ia6_createtime) -
1435 V_ip6_desync_factor;
1436 } else
1437 maxvltime = 0;
1438 if (V_ip6_temp_preferred_lifetime >
1439 (u_int32_t)((time_uptime - ifa6->ia6_createtime) +
1440 V_ip6_desync_factor)) {
1441 maxpltime = V_ip6_temp_preferred_lifetime -
1442 (time_uptime - ifa6->ia6_createtime) -
1443 V_ip6_desync_factor;
1444 } else
1445 maxpltime = 0;
1446
1447 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME ||
1448 lt6_tmp.ia6t_vltime > maxvltime) {
1449 lt6_tmp.ia6t_vltime = maxvltime;
1450 }
1451 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME ||
1452 lt6_tmp.ia6t_pltime > maxpltime) {
1453 lt6_tmp.ia6t_pltime = maxpltime;
1454 }
1455 }
1456 ifa6->ia6_lifetime = lt6_tmp;
1457 ifa6->ia6_updatetime = time_uptime;
1458 }
1459 IF_ADDR_RUNLOCK(ifp);
1460 if (ia6_match == NULL && new->ndpr_vltime) {
1461 int ifidlen;
1462
1463 /*
1464 * 5.5.3 (d) (continued)
1465 * No address matched and the valid lifetime is non-zero.
1466 * Create a new address.
1467 */
1468
1469 /*
1470 * Prefix Length check:
1471 * If the sum of the prefix length and interface identifier
1472 * length does not equal 128 bits, the Prefix Information
1473 * option MUST be ignored. The length of the interface
1474 * identifier is defined in a separate link-type specific
1475 * document.
1476 */
1477 ifidlen = in6_if2idlen(ifp);
1478 if (ifidlen < 0) {
1479 /* this should not happen, so we always log it. */
1480 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n",
1481 if_name(ifp));
1482 goto end;
1483 }
1484 if (ifidlen + pr->ndpr_plen != 128) {
1485 nd6log((LOG_INFO,
1486 "prelist_update: invalid prefixlen "
1487 "%d for %s, ignored\n",
1488 pr->ndpr_plen, if_name(ifp)));
1489 goto end;
1490 }
1491
1492 if ((ia6 = in6_ifadd(new, mcast)) != NULL) {
1493 /*
1494 * note that we should use pr (not new) for reference.
1495 */
1496 pr->ndpr_addrcnt++;
1497 ia6->ia6_ndpr = pr;
1498
1499 /*
1500 * RFC 3041 3.3 (2).
1501 * When a new public address is created as described
1502 * in RFC2462, also create a new temporary address.
1503 *
1504 * RFC 3041 3.5.
1505 * When an interface connects to a new link, a new
1506 * randomized interface identifier should be generated
1507 * immediately together with a new set of temporary
1508 * addresses. Thus, we specifiy 1 as the 2nd arg of
1509 * in6_tmpifadd().
1510 */
1511 if (V_ip6_use_tempaddr) {
1512 int e;
1513 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) {
1514 nd6log((LOG_NOTICE, "prelist_update: "
1515 "failed to create a temporary "
1516 "address, errno=%d\n",
1517 e));
1518 }
1519 }
1520 ifa_free(&ia6->ia_ifa);
1521
1522 /*
1523 * A newly added address might affect the status
1524 * of other addresses, so we check and update it.
1525 * XXX: what if address duplication happens?
1526 */
1527 pfxlist_onlink_check();
1528 } else {
1529 /* just set an error. do not bark here. */
1530 error = EADDRNOTAVAIL; /* XXX: might be unused. */
1531 }
1532 }
1533
1534 end:
1535 if (pr != NULL)
1536 nd6_prefix_rele(pr);
1537 return (error);
1538 }
1539
1540 /*
1541 * A supplement function used in the on-link detection below;
1542 * detect if a given prefix has a (probably) reachable advertising router.
1543 * XXX: lengthy function name...
1544 */
1545 static struct nd_pfxrouter *
1546 find_pfxlist_reachable_router(struct nd_prefix *pr)
1547 {
1548 struct nd_pfxrouter *pfxrtr;
1549 struct llentry *ln;
1550 int canreach;
1551
1552 ND6_LOCK_ASSERT();
1553
1554 LIST_FOREACH(pfxrtr, &pr->ndpr_advrtrs, pfr_entry) {
1555 IF_AFDATA_RLOCK(pfxrtr->router->ifp);
1556 ln = nd6_lookup(&pfxrtr->router->rtaddr, 0, pfxrtr->router->ifp);
1557 IF_AFDATA_RUNLOCK(pfxrtr->router->ifp);
1558 if (ln == NULL)
1559 continue;
1560 canreach = ND6_IS_LLINFO_PROBREACH(ln);
1561 LLE_RUNLOCK(ln);
1562 if (canreach)
1563 break;
1564 }
1565 return (pfxrtr);
1566 }
1567
1568 /*
1569 * Check if each prefix in the prefix list has at least one available router
1570 * that advertised the prefix (a router is "available" if its neighbor cache
1571 * entry is reachable or probably reachable).
1572 * If the check fails, the prefix may be off-link, because, for example,
1573 * we have moved from the network but the lifetime of the prefix has not
1574 * expired yet. So we should not use the prefix if there is another prefix
1575 * that has an available router.
1576 * But, if there is no prefix that has an available router, we still regard
1577 * all the prefixes as on-link. This is because we can't tell if all the
1578 * routers are simply dead or if we really moved from the network and there
1579 * is no router around us.
1580 */
1581 void
1582 pfxlist_onlink_check(void)
1583 {
1584 struct nd_prefix *pr;
1585 struct in6_ifaddr *ifa;
1586 struct nd_defrouter *dr;
1587 struct nd_pfxrouter *pfxrtr = NULL;
1588 struct rm_priotracker in6_ifa_tracker;
1589 uint64_t genid;
1590 uint32_t flags;
1591
1592 ND6_ONLINK_LOCK();
1593 ND6_RLOCK();
1594
1595 /*
1596 * Check if there is a prefix that has a reachable advertising
1597 * router.
1598 */
1599 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1600 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr))
1601 break;
1602 }
1603
1604 /*
1605 * If we have no such prefix, check whether we still have a router
1606 * that does not advertise any prefixes.
1607 */
1608 if (pr == NULL) {
1609 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
1610 struct nd_prefix *pr0;
1611
1612 LIST_FOREACH(pr0, &V_nd_prefix, ndpr_entry) {
1613 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL)
1614 break;
1615 }
1616 if (pfxrtr != NULL)
1617 break;
1618 }
1619 }
1620 if (pr != NULL || (!TAILQ_EMPTY(&V_nd_defrouter) && pfxrtr == NULL)) {
1621 /*
1622 * There is at least one prefix that has a reachable router,
1623 * or at least a router which probably does not advertise
1624 * any prefixes. The latter would be the case when we move
1625 * to a new link where we have a router that does not provide
1626 * prefixes and we configure an address by hand.
1627 * Detach prefixes which have no reachable advertising
1628 * router, and attach other prefixes.
1629 */
1630 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1631 /* XXX: a link-local prefix should never be detached */
1632 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) ||
1633 pr->ndpr_raf_onlink == 0 ||
1634 pr->ndpr_raf_auto == 0)
1635 continue;
1636
1637 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 &&
1638 find_pfxlist_reachable_router(pr) == NULL)
1639 pr->ndpr_stateflags |= NDPRF_DETACHED;
1640 else if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 &&
1641 find_pfxlist_reachable_router(pr) != NULL)
1642 pr->ndpr_stateflags &= ~NDPRF_DETACHED;
1643 }
1644 } else {
1645 /* there is no prefix that has a reachable router */
1646 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1647 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) ||
1648 pr->ndpr_raf_onlink == 0 ||
1649 pr->ndpr_raf_auto == 0)
1650 continue;
1651 pr->ndpr_stateflags &= ~NDPRF_DETACHED;
1652 }
1653 }
1654
1655 /*
1656 * Remove each interface route associated with a (just) detached
1657 * prefix, and reinstall the interface route for a (just) attached
1658 * prefix. Note that all attempt of reinstallation does not
1659 * necessarily success, when a same prefix is shared among multiple
1660 * interfaces. Such cases will be handled in nd6_prefix_onlink,
1661 * so we don't have to care about them.
1662 */
1663 restart:
1664 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
1665 char ip6buf[INET6_ADDRSTRLEN];
1666 int e;
1667
1668 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) ||
1669 pr->ndpr_raf_onlink == 0 ||
1670 pr->ndpr_raf_auto == 0)
1671 continue;
1672
1673 flags = pr->ndpr_stateflags & (NDPRF_DETACHED | NDPRF_ONLINK);
1674 if (flags == 0 || flags == (NDPRF_DETACHED | NDPRF_ONLINK)) {
1675 genid = V_nd6_list_genid;
1676 ND6_RUNLOCK();
1677 if ((flags & NDPRF_ONLINK) != 0 &&
1678 (e = nd6_prefix_offlink(pr)) != 0) {
1679 nd6log((LOG_ERR,
1680 "pfxlist_onlink_check: failed to "
1681 "make %s/%d offlink, errno=%d\n",
1682 ip6_sprintf(ip6buf,
1683 &pr->ndpr_prefix.sin6_addr),
1684 pr->ndpr_plen, e));
1685 } else if ((flags & NDPRF_ONLINK) == 0 &&
1686 (e = nd6_prefix_onlink(pr)) != 0) {
1687 nd6log((LOG_ERR,
1688 "pfxlist_onlink_check: failed to "
1689 "make %s/%d onlink, errno=%d\n",
1690 ip6_sprintf(ip6buf,
1691 &pr->ndpr_prefix.sin6_addr),
1692 pr->ndpr_plen, e));
1693 }
1694 ND6_RLOCK();
1695 if (genid != V_nd6_list_genid)
1696 goto restart;
1697 }
1698 }
1699
1700 /*
1701 * Changes on the prefix status might affect address status as well.
1702 * Make sure that all addresses derived from an attached prefix are
1703 * attached, and that all addresses derived from a detached prefix are
1704 * detached. Note, however, that a manually configured address should
1705 * always be attached.
1706 * The precise detection logic is same as the one for prefixes.
1707 */
1708 IN6_IFADDR_RLOCK(&in6_ifa_tracker);
1709 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) {
1710 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF))
1711 continue;
1712
1713 if (ifa->ia6_ndpr == NULL) {
1714 /*
1715 * This can happen when we first configure the address
1716 * (i.e. the address exists, but the prefix does not).
1717 * XXX: complicated relationships...
1718 */
1719 continue;
1720 }
1721
1722 if (find_pfxlist_reachable_router(ifa->ia6_ndpr))
1723 break;
1724 }
1725 if (ifa) {
1726 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) {
1727 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1728 continue;
1729
1730 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */
1731 continue;
1732
1733 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) {
1734 if (ifa->ia6_flags & IN6_IFF_DETACHED) {
1735 ifa->ia6_flags &= ~IN6_IFF_DETACHED;
1736 ifa->ia6_flags |= IN6_IFF_TENTATIVE;
1737 nd6_dad_start((struct ifaddr *)ifa, 0);
1738 }
1739 } else {
1740 ifa->ia6_flags |= IN6_IFF_DETACHED;
1741 }
1742 }
1743 } else {
1744 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) {
1745 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1746 continue;
1747
1748 if (ifa->ia6_flags & IN6_IFF_DETACHED) {
1749 ifa->ia6_flags &= ~IN6_IFF_DETACHED;
1750 ifa->ia6_flags |= IN6_IFF_TENTATIVE;
1751 /* Do we need a delay in this case? */
1752 nd6_dad_start((struct ifaddr *)ifa, 0);
1753 }
1754 }
1755 }
1756 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
1757 ND6_RUNLOCK();
1758 ND6_ONLINK_UNLOCK();
1759 }
1760
1761 static int
1762 nd6_prefix_onlink_rtrequest(struct nd_prefix *pr, struct ifaddr *ifa)
1763 {
1764 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
1765 struct rib_head *rnh;
1766 struct rtentry *rt;
1767 struct sockaddr_in6 mask6;
1768 u_long rtflags;
1769 int error, a_failure, fibnum, maxfib;
1770
1771 /*
1772 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs.
1773 * ifa->ifa_rtrequest = nd6_rtrequest;
1774 */
1775 bzero(&mask6, sizeof(mask6));
1776 mask6.sin6_len = sizeof(mask6);
1777 mask6.sin6_addr = pr->ndpr_mask;
1778 rtflags = (ifa->ifa_flags & ~IFA_RTSELF) | RTF_UP;
1779
1780 if(V_rt_add_addr_allfibs) {
1781 fibnum = 0;
1782 maxfib = rt_numfibs;
1783 } else {
1784 fibnum = ifa->ifa_ifp->if_fib;
1785 maxfib = fibnum + 1;
1786 }
1787 a_failure = 0;
1788 for (; fibnum < maxfib; fibnum++) {
1789
1790 rt = NULL;
1791 error = in6_rtrequest(RTM_ADD,
1792 (struct sockaddr *)&pr->ndpr_prefix, ifa->ifa_addr,
1793 (struct sockaddr *)&mask6, rtflags, &rt, fibnum);
1794 if (error == 0) {
1795 KASSERT(rt != NULL, ("%s: in6_rtrequest return no "
1796 "error(%d) but rt is NULL, pr=%p, ifa=%p", __func__,
1797 error, pr, ifa));
1798
1799 rnh = rt_tables_get_rnh(rt->rt_fibnum, AF_INET6);
1800 /* XXX what if rhn == NULL? */
1801 RIB_WLOCK(rnh);
1802 RT_LOCK(rt);
1803 if (rt_setgate(rt, rt_key(rt),
1804 (struct sockaddr *)&null_sdl) == 0) {
1805 struct sockaddr_dl *dl;
1806
1807 dl = (struct sockaddr_dl *)rt->rt_gateway;
1808 dl->sdl_type = rt->rt_ifp->if_type;
1809 dl->sdl_index = rt->rt_ifp->if_index;
1810 }
1811 RIB_WUNLOCK(rnh);
1812 nd6_rtmsg(RTM_ADD, rt);
1813 RT_UNLOCK(rt);
1814 pr->ndpr_stateflags |= NDPRF_ONLINK;
1815 } else {
1816 char ip6buf[INET6_ADDRSTRLEN];
1817 char ip6bufg[INET6_ADDRSTRLEN];
1818 char ip6bufm[INET6_ADDRSTRLEN];
1819 struct sockaddr_in6 *sin6;
1820
1821 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
1822 nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add "
1823 "route for a prefix (%s/%d) on %s, gw=%s, mask=%s, "
1824 "flags=%lx errno = %d\n",
1825 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
1826 pr->ndpr_plen, if_name(pr->ndpr_ifp),
1827 ip6_sprintf(ip6bufg, &sin6->sin6_addr),
1828 ip6_sprintf(ip6bufm, &mask6.sin6_addr),
1829 rtflags, error));
1830
1831 /* Save last error to return, see rtinit(). */
1832 a_failure = error;
1833 }
1834
1835 if (rt != NULL) {
1836 RT_LOCK(rt);
1837 RT_REMREF(rt);
1838 RT_UNLOCK(rt);
1839 }
1840 }
1841
1842 /* Return the last error we got. */
1843 return (a_failure);
1844 }
1845
1846 int
1847 nd6_prefix_onlink(struct nd_prefix *pr)
1848 {
1849 struct ifaddr *ifa;
1850 struct ifnet *ifp = pr->ndpr_ifp;
1851 struct nd_prefix *opr;
1852 char ip6buf[INET6_ADDRSTRLEN];
1853 int error;
1854
1855 ND6_ONLINK_LOCK_ASSERT();
1856 ND6_UNLOCK_ASSERT();
1857
1858 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0)
1859 return (EEXIST);
1860
1861 /*
1862 * Add the interface route associated with the prefix. Before
1863 * installing the route, check if there's the same prefix on another
1864 * interface, and the prefix has already installed the interface route.
1865 * Although such a configuration is expected to be rare, we explicitly
1866 * allow it.
1867 */
1868 ND6_RLOCK();
1869 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) {
1870 if (opr == pr)
1871 continue;
1872
1873 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0)
1874 continue;
1875
1876 if (!V_rt_add_addr_allfibs &&
1877 opr->ndpr_ifp->if_fib != pr->ndpr_ifp->if_fib)
1878 continue;
1879
1880 if (opr->ndpr_plen == pr->ndpr_plen &&
1881 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
1882 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) {
1883 ND6_RUNLOCK();
1884 return (0);
1885 }
1886 }
1887 ND6_RUNLOCK();
1888
1889 /*
1890 * We prefer link-local addresses as the associated interface address.
1891 */
1892 /* search for a link-local addr */
1893 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
1894 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST);
1895 if (ifa == NULL) {
1896 /* XXX: freebsd does not have ifa_ifwithaf */
1897 IF_ADDR_RLOCK(ifp);
1898 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1899 if (ifa->ifa_addr->sa_family == AF_INET6) {
1900 ifa_ref(ifa);
1901 break;
1902 }
1903 }
1904 IF_ADDR_RUNLOCK(ifp);
1905 /* should we care about ia6_flags? */
1906 }
1907 if (ifa == NULL) {
1908 /*
1909 * This can still happen, when, for example, we receive an RA
1910 * containing a prefix with the L bit set and the A bit clear,
1911 * after removing all IPv6 addresses on the receiving
1912 * interface. This should, of course, be rare though.
1913 */
1914 nd6log((LOG_NOTICE,
1915 "nd6_prefix_onlink: failed to find any ifaddr"
1916 " to add route for a prefix(%s/%d) on %s\n",
1917 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
1918 pr->ndpr_plen, if_name(ifp)));
1919 return (0);
1920 }
1921
1922 error = nd6_prefix_onlink_rtrequest(pr, ifa);
1923
1924 if (ifa != NULL)
1925 ifa_free(ifa);
1926
1927 return (error);
1928 }
1929
1930 int
1931 nd6_prefix_offlink(struct nd_prefix *pr)
1932 {
1933 int error = 0;
1934 struct ifnet *ifp = pr->ndpr_ifp;
1935 struct nd_prefix *opr;
1936 struct sockaddr_in6 sa6, mask6;
1937 struct rtentry *rt;
1938 char ip6buf[INET6_ADDRSTRLEN];
1939 uint64_t genid;
1940 int fibnum, maxfib, a_failure;
1941
1942 ND6_ONLINK_LOCK_ASSERT();
1943 ND6_UNLOCK_ASSERT();
1944
1945 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0)
1946 return (EEXIST);
1947
1948 bzero(&sa6, sizeof(sa6));
1949 sa6.sin6_family = AF_INET6;
1950 sa6.sin6_len = sizeof(sa6);
1951 bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr,
1952 sizeof(struct in6_addr));
1953 bzero(&mask6, sizeof(mask6));
1954 mask6.sin6_family = AF_INET6;
1955 mask6.sin6_len = sizeof(sa6);
1956 bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr));
1957
1958 if (V_rt_add_addr_allfibs) {
1959 fibnum = 0;
1960 maxfib = rt_numfibs;
1961 } else {
1962 fibnum = ifp->if_fib;
1963 maxfib = fibnum + 1;
1964 }
1965
1966 a_failure = 0;
1967 for (; fibnum < maxfib; fibnum++) {
1968 rt = NULL;
1969 error = in6_rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL,
1970 (struct sockaddr *)&mask6, 0, &rt, fibnum);
1971 if (error == 0) {
1972 /* report the route deletion to the routing socket. */
1973 if (rt != NULL)
1974 nd6_rtmsg(RTM_DELETE, rt);
1975 } else {
1976 /* Save last error to return, see rtinit(). */
1977 a_failure = error;
1978 }
1979 if (rt != NULL) {
1980 RTFREE(rt);
1981 }
1982 }
1983 error = a_failure;
1984 a_failure = 1;
1985 if (error == 0) {
1986 pr->ndpr_stateflags &= ~NDPRF_ONLINK;
1987
1988 /*
1989 * There might be the same prefix on another interface,
1990 * the prefix which could not be on-link just because we have
1991 * the interface route (see comments in nd6_prefix_onlink).
1992 * If there's one, try to make the prefix on-link on the
1993 * interface.
1994 */
1995 ND6_RLOCK();
1996 restart:
1997 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) {
1998 /*
1999 * KAME specific: detached prefixes should not be
2000 * on-link.
2001 */
2002 if (opr == pr || (opr->ndpr_stateflags &
2003 (NDPRF_ONLINK | NDPRF_DETACHED)) != 0)
2004 continue;
2005
2006 if (opr->ndpr_plen == pr->ndpr_plen &&
2007 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
2008 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) {
2009 int e;
2010
2011 genid = V_nd6_list_genid;
2012 ND6_RUNLOCK();
2013 if ((e = nd6_prefix_onlink(opr)) != 0) {
2014 nd6log((LOG_ERR,
2015 "nd6_prefix_offlink: failed to "
2016 "recover a prefix %s/%d from %s "
2017 "to %s (errno = %d)\n",
2018 ip6_sprintf(ip6buf,
2019 &opr->ndpr_prefix.sin6_addr),
2020 opr->ndpr_plen, if_name(ifp),
2021 if_name(opr->ndpr_ifp), e));
2022 } else
2023 a_failure = 0;
2024 ND6_RLOCK();
2025 if (genid != V_nd6_list_genid)
2026 goto restart;
2027 }
2028 }
2029 ND6_RUNLOCK();
2030 } else {
2031 /* XXX: can we still set the NDPRF_ONLINK flag? */
2032 nd6log((LOG_ERR,
2033 "nd6_prefix_offlink: failed to delete route: "
2034 "%s/%d on %s (errno = %d)\n",
2035 ip6_sprintf(ip6buf, &sa6.sin6_addr), pr->ndpr_plen,
2036 if_name(ifp), error));
2037 }
2038
2039 if (a_failure)
2040 lltable_prefix_free(AF_INET6, (struct sockaddr *)&sa6,
2041 (struct sockaddr *)&mask6, LLE_STATIC);
2042
2043 return (error);
2044 }
2045
2046 static struct in6_ifaddr *
2047 in6_ifadd(struct nd_prefixctl *pr, int mcast)
2048 {
2049 struct ifnet *ifp = pr->ndpr_ifp;
2050 struct ifaddr *ifa;
2051 struct in6_aliasreq ifra;
2052 struct in6_ifaddr *ia, *ib;
2053 int error, plen0;
2054 struct in6_addr mask;
2055 int prefixlen = pr->ndpr_plen;
2056 int updateflags;
2057 char ip6buf[INET6_ADDRSTRLEN];
2058
2059 in6_prefixlen2mask(&mask, prefixlen);
2060
2061 /*
2062 * find a link-local address (will be interface ID).
2063 * Is it really mandatory? Theoretically, a global or a site-local
2064 * address can be configured without a link-local address, if we
2065 * have a unique interface identifier...
2066 *
2067 * it is not mandatory to have a link-local address, we can generate
2068 * interface identifier on the fly. we do this because:
2069 * (1) it should be the easiest way to find interface identifier.
2070 * (2) RFC2462 5.4 suggesting the use of the same interface identifier
2071 * for multiple addresses on a single interface, and possible shortcut
2072 * of DAD. we omitted DAD for this reason in the past.
2073 * (3) a user can prevent autoconfiguration of global address
2074 * by removing link-local address by hand (this is partly because we
2075 * don't have other way to control the use of IPv6 on an interface.
2076 * this has been our design choice - cf. NRL's "ifconfig auto").
2077 * (4) it is easier to manage when an interface has addresses
2078 * with the same interface identifier, than to have multiple addresses
2079 * with different interface identifiers.
2080 */
2081 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */
2082 if (ifa)
2083 ib = (struct in6_ifaddr *)ifa;
2084 else
2085 return NULL;
2086
2087 /* prefixlen + ifidlen must be equal to 128 */
2088 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL);
2089 if (prefixlen != plen0) {
2090 ifa_free(ifa);
2091 nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s "
2092 "(prefix=%d ifid=%d)\n",
2093 if_name(ifp), prefixlen, 128 - plen0));
2094 return NULL;
2095 }
2096
2097 /* make ifaddr */
2098 in6_prepare_ifra(&ifra, &pr->ndpr_prefix.sin6_addr, &mask);
2099
2100 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, &mask);
2101 /* interface ID */
2102 ifra.ifra_addr.sin6_addr.s6_addr32[0] |=
2103 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]);
2104 ifra.ifra_addr.sin6_addr.s6_addr32[1] |=
2105 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]);
2106 ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
2107 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]);
2108 ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
2109 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]);
2110 ifa_free(ifa);
2111
2112 /* lifetimes. */
2113 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime;
2114 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime;
2115
2116 /* XXX: scope zone ID? */
2117
2118 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */
2119
2120 /*
2121 * Make sure that we do not have this address already. This should
2122 * usually not happen, but we can still see this case, e.g., if we
2123 * have manually configured the exact address to be configured.
2124 */
2125 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp,
2126 &ifra.ifra_addr.sin6_addr);
2127 if (ifa != NULL) {
2128 ifa_free(ifa);
2129 /* this should be rare enough to make an explicit log */
2130 log(LOG_INFO, "in6_ifadd: %s is already configured\n",
2131 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr));
2132 return (NULL);
2133 }
2134
2135 /*
2136 * Allocate ifaddr structure, link into chain, etc.
2137 * If we are going to create a new address upon receiving a multicasted
2138 * RA, we need to impose a random delay before starting DAD.
2139 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2]
2140 */
2141 updateflags = 0;
2142 if (mcast)
2143 updateflags |= IN6_IFAUPDATE_DADDELAY;
2144 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) {
2145 nd6log((LOG_ERR,
2146 "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n",
2147 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr),
2148 if_name(ifp), error));
2149 return (NULL); /* ifaddr must not have been allocated. */
2150 }
2151
2152 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
2153 /*
2154 * XXXRW: Assumption of non-NULLness here might not be true with
2155 * fine-grained locking -- should we validate it? Or just return
2156 * earlier ifa rather than looking it up again?
2157 */
2158 return (ia); /* this is always non-NULL and referenced. */
2159 }
2160
2161 /*
2162 * ia0 - corresponding public address
2163 */
2164 int
2165 in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay)
2166 {
2167 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp;
2168 struct in6_ifaddr *newia;
2169 struct in6_aliasreq ifra;
2170 int error;
2171 int trylimit = 3; /* XXX: adhoc value */
2172 int updateflags;
2173 u_int32_t randid[2];
2174 time_t vltime0, pltime0;
2175
2176 in6_prepare_ifra(&ifra, &ia0->ia_addr.sin6_addr,
2177 &ia0->ia_prefixmask.sin6_addr);
2178
2179 ifra.ifra_addr = ia0->ia_addr; /* XXX: do we need this ? */
2180 /* clear the old IFID */
2181 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr,
2182 &ifra.ifra_prefixmask.sin6_addr);
2183
2184 again:
2185 if (in6_get_tmpifid(ifp, (u_int8_t *)randid,
2186 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) {
2187 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good "
2188 "random IFID\n"));
2189 return (EINVAL);
2190 }
2191 ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
2192 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2]));
2193 ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
2194 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3]));
2195
2196 /*
2197 * in6_get_tmpifid() quite likely provided a unique interface ID.
2198 * However, we may still have a chance to see collision, because
2199 * there may be a time lag between generation of the ID and generation
2200 * of the address. So, we'll do one more sanity check.
2201 */
2202
2203 if (in6_localip(&ifra.ifra_addr.sin6_addr) != 0) {
2204 if (trylimit-- > 0) {
2205 forcegen = 1;
2206 goto again;
2207 }
2208
2209 /* Give up. Something strange should have happened. */
2210 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to "
2211 "find a unique random IFID\n"));
2212 return (EEXIST);
2213 }
2214
2215 /*
2216 * The Valid Lifetime is the lower of the Valid Lifetime of the
2217 * public address or TEMP_VALID_LIFETIME.
2218 * The Preferred Lifetime is the lower of the Preferred Lifetime
2219 * of the public address or TEMP_PREFERRED_LIFETIME -
2220 * DESYNC_FACTOR.
2221 */
2222 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
2223 vltime0 = IFA6_IS_INVALID(ia0) ? 0 :
2224 (ia0->ia6_lifetime.ia6t_vltime -
2225 (time_uptime - ia0->ia6_updatetime));
2226 if (vltime0 > V_ip6_temp_valid_lifetime)
2227 vltime0 = V_ip6_temp_valid_lifetime;
2228 } else
2229 vltime0 = V_ip6_temp_valid_lifetime;
2230 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
2231 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 :
2232 (ia0->ia6_lifetime.ia6t_pltime -
2233 (time_uptime - ia0->ia6_updatetime));
2234 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){
2235 pltime0 = V_ip6_temp_preferred_lifetime -
2236 V_ip6_desync_factor;
2237 }
2238 } else
2239 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor;
2240 ifra.ifra_lifetime.ia6t_vltime = vltime0;
2241 ifra.ifra_lifetime.ia6t_pltime = pltime0;
2242
2243 /*
2244 * A temporary address is created only if this calculated Preferred
2245 * Lifetime is greater than REGEN_ADVANCE time units.
2246 */
2247 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance)
2248 return (0);
2249
2250 /* XXX: scope zone ID? */
2251
2252 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY);
2253
2254 /* allocate ifaddr structure, link into chain, etc. */
2255 updateflags = 0;
2256 if (delay)
2257 updateflags |= IN6_IFAUPDATE_DADDELAY;
2258 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0)
2259 return (error);
2260
2261 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
2262 if (newia == NULL) { /* XXX: can it happen? */
2263 nd6log((LOG_ERR,
2264 "in6_tmpifadd: ifa update succeeded, but we got "
2265 "no ifaddr\n"));
2266 return (EINVAL); /* XXX */
2267 }
2268 newia->ia6_ndpr = ia0->ia6_ndpr;
2269 newia->ia6_ndpr->ndpr_addrcnt++;
2270 ifa_free(&newia->ia_ifa);
2271
2272 /*
2273 * A newly added address might affect the status of other addresses.
2274 * XXX: when the temporary address is generated with a new public
2275 * address, the onlink check is redundant. However, it would be safe
2276 * to do the check explicitly everywhere a new address is generated,
2277 * and, in fact, we surely need the check when we create a new
2278 * temporary address due to deprecation of an old temporary address.
2279 */
2280 pfxlist_onlink_check();
2281
2282 return (0);
2283 }
2284
2285 static int
2286 in6_init_prefix_ltimes(struct nd_prefix *ndpr)
2287 {
2288 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME)
2289 ndpr->ndpr_preferred = 0;
2290 else
2291 ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime;
2292 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME)
2293 ndpr->ndpr_expire = 0;
2294 else
2295 ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime;
2296
2297 return 0;
2298 }
2299
2300 static void
2301 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6)
2302 {
2303 /* init ia6t_expire */
2304 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME)
2305 lt6->ia6t_expire = 0;
2306 else {
2307 lt6->ia6t_expire = time_uptime;
2308 lt6->ia6t_expire += lt6->ia6t_vltime;
2309 }
2310
2311 /* init ia6t_preferred */
2312 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME)
2313 lt6->ia6t_preferred = 0;
2314 else {
2315 lt6->ia6t_preferred = time_uptime;
2316 lt6->ia6t_preferred += lt6->ia6t_pltime;
2317 }
2318 }
2319
2320 /*
2321 * Delete all the routing table entries that use the specified gateway.
2322 * XXX: this function causes search through all entries of routing table, so
2323 * it shouldn't be called when acting as a router.
2324 */
2325 void
2326 rt6_flush(struct in6_addr *gateway, struct ifnet *ifp)
2327 {
2328
2329 /* We'll care only link-local addresses */
2330 if (!IN6_IS_ADDR_LINKLOCAL(gateway))
2331 return;
2332
2333 /* XXX Do we really need to walk any but the default FIB? */
2334 rt_foreach_fib_walk_del(AF_INET6, rt6_deleteroute, (void *)gateway);
2335 }
2336
2337 static int
2338 rt6_deleteroute(const struct rtentry *rt, void *arg)
2339 {
2340 #define SIN6(s) ((struct sockaddr_in6 *)s)
2341 struct in6_addr *gate = (struct in6_addr *)arg;
2342
2343 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6)
2344 return (0);
2345
2346 if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) {
2347 return (0);
2348 }
2349
2350 /*
2351 * Do not delete a static route.
2352 * XXX: this seems to be a bit ad-hoc. Should we consider the
2353 * 'cloned' bit instead?
2354 */
2355 if ((rt->rt_flags & RTF_STATIC) != 0)
2356 return (0);
2357
2358 /*
2359 * We delete only host route. This means, in particular, we don't
2360 * delete default route.
2361 */
2362 if ((rt->rt_flags & RTF_HOST) == 0)
2363 return (0);
2364
2365 return (1);
2366 #undef SIN6
2367 }
2368
2369 int
2370 nd6_setdefaultiface(int ifindex)
2371 {
2372 int error = 0;
2373
2374 if (ifindex < 0 || V_if_index < ifindex)
2375 return (EINVAL);
2376 if (ifindex != 0 && !ifnet_byindex(ifindex))
2377 return (EINVAL);
2378
2379 if (V_nd6_defifindex != ifindex) {
2380 V_nd6_defifindex = ifindex;
2381 if (V_nd6_defifindex > 0)
2382 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex);
2383 else
2384 V_nd6_defifp = NULL;
2385
2386 /*
2387 * Our current implementation assumes one-to-one maping between
2388 * interfaces and links, so it would be natural to use the
2389 * default interface as the default link.
2390 */
2391 scope6_setdefault(V_nd6_defifp);
2392 }
2393
2394 return (error);
2395 }
Cache object: 647c0ebfe27cce456e7d1d359426c808
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