1 /* $FreeBSD: releng/6.3/sys/netinet6/nd6_rtr.c 156912 2006-03-20 16:23:08Z suz $ */
2 /* $KAME: nd6_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $ */
3
4 /*-
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/malloc.h>
39 #include <sys/mbuf.h>
40 #include <sys/socket.h>
41 #include <sys/sockio.h>
42 #include <sys/time.h>
43 #include <sys/kernel.h>
44 #include <sys/errno.h>
45 #include <sys/syslog.h>
46 #include <sys/queue.h>
47
48 #include <net/if.h>
49 #include <net/if_types.h>
50 #include <net/if_dl.h>
51 #include <net/route.h>
52 #include <net/radix.h>
53
54 #include <netinet/in.h>
55 #include <netinet6/in6_var.h>
56 #include <netinet6/in6_ifattach.h>
57 #include <netinet/ip6.h>
58 #include <netinet6/ip6_var.h>
59 #include <netinet6/nd6.h>
60 #include <netinet/icmp6.h>
61 #include <netinet6/scope6_var.h>
62
63 #include <net/net_osdep.h>
64
65 #define SDL(s) ((struct sockaddr_dl *)s)
66
67 static int rtpref __P((struct nd_defrouter *));
68 static struct nd_defrouter *defrtrlist_update __P((struct nd_defrouter *));
69 static int prelist_update __P((struct nd_prefixctl *, struct nd_defrouter *,
70 struct mbuf *, int));
71 static struct in6_ifaddr *in6_ifadd __P((struct nd_prefixctl *, int));
72 static struct nd_pfxrouter *pfxrtr_lookup __P((struct nd_prefix *,
73 struct nd_defrouter *));
74 static void pfxrtr_add __P((struct nd_prefix *, struct nd_defrouter *));
75 static void pfxrtr_del __P((struct nd_pfxrouter *));
76 static struct nd_pfxrouter *find_pfxlist_reachable_router
77 __P((struct nd_prefix *));
78 static void defrouter_delreq __P((struct nd_defrouter *));
79 static void nd6_rtmsg __P((int, struct rtentry *));
80
81 static int in6_init_prefix_ltimes __P((struct nd_prefix *));
82 static void in6_init_address_ltimes __P((struct nd_prefix *,
83 struct in6_addrlifetime *));
84
85 static int rt6_deleteroute __P((struct radix_node *, void *));
86
87 extern int nd6_recalc_reachtm_interval;
88
89 static struct ifnet *nd6_defifp;
90 int nd6_defifindex;
91
92 int ip6_use_tempaddr = 0;
93
94 int ip6_desync_factor;
95 u_int32_t ip6_temp_preferred_lifetime = DEF_TEMP_PREFERRED_LIFETIME;
96 u_int32_t ip6_temp_valid_lifetime = DEF_TEMP_VALID_LIFETIME;
97 /*
98 * shorter lifetimes for debugging purposes.
99 int ip6_temp_preferred_lifetime = 800;
100 static int ip6_temp_valid_lifetime = 1800;
101 */
102 int ip6_temp_regen_advance = TEMPADDR_REGEN_ADVANCE;
103
104 /* RTPREF_MEDIUM has to be 0! */
105 #define RTPREF_HIGH 1
106 #define RTPREF_MEDIUM 0
107 #define RTPREF_LOW (-1)
108 #define RTPREF_RESERVED (-2)
109 #define RTPREF_INVALID (-3) /* internal */
110
111 /*
112 * Receive Router Solicitation Message - just for routers.
113 * Router solicitation/advertisement is mostly managed by userland program
114 * (rtadvd) so here we have no function like nd6_ra_output().
115 *
116 * Based on RFC 2461
117 */
118 void
119 nd6_rs_input(m, off, icmp6len)
120 struct mbuf *m;
121 int off, icmp6len;
122 {
123 struct ifnet *ifp = m->m_pkthdr.rcvif;
124 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
125 struct nd_router_solicit *nd_rs;
126 struct in6_addr saddr6 = ip6->ip6_src;
127 char *lladdr = NULL;
128 int lladdrlen = 0;
129 union nd_opts ndopts;
130
131 /* If I'm not a router, ignore it. */
132 if (ip6_accept_rtadv != 0 || ip6_forwarding != 1)
133 goto freeit;
134
135 /* Sanity checks */
136 if (ip6->ip6_hlim != 255) {
137 nd6log((LOG_ERR,
138 "nd6_rs_input: invalid hlim (%d) from %s to %s on %s\n",
139 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
140 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
141 goto bad;
142 }
143
144 /*
145 * Don't update the neighbor cache, if src = ::.
146 * This indicates that the src has no IP address assigned yet.
147 */
148 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
149 goto freeit;
150
151 #ifndef PULLDOWN_TEST
152 IP6_EXTHDR_CHECK(m, off, icmp6len,);
153 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off);
154 #else
155 IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len);
156 if (nd_rs == NULL) {
157 icmp6stat.icp6s_tooshort++;
158 return;
159 }
160 #endif
161
162 icmp6len -= sizeof(*nd_rs);
163 nd6_option_init(nd_rs + 1, icmp6len, &ndopts);
164 if (nd6_options(&ndopts) < 0) {
165 nd6log((LOG_INFO,
166 "nd6_rs_input: invalid ND option, ignored\n"));
167 /* nd6_options have incremented stats */
168 goto freeit;
169 }
170
171 if (ndopts.nd_opts_src_lladdr) {
172 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
173 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
174 }
175
176 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
177 nd6log((LOG_INFO,
178 "nd6_rs_input: lladdrlen mismatch for %s "
179 "(if %d, RS packet %d)\n",
180 ip6_sprintf(&saddr6),
181 ifp->if_addrlen, lladdrlen - 2));
182 goto bad;
183 }
184
185 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0);
186
187 freeit:
188 m_freem(m);
189 return;
190
191 bad:
192 icmp6stat.icp6s_badrs++;
193 m_freem(m);
194 }
195
196 /*
197 * Receive Router Advertisement Message.
198 *
199 * Based on RFC 2461
200 * TODO: on-link bit on prefix information
201 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing
202 */
203 void
204 nd6_ra_input(m, off, icmp6len)
205 struct mbuf *m;
206 int off, icmp6len;
207 {
208 struct ifnet *ifp = m->m_pkthdr.rcvif;
209 struct nd_ifinfo *ndi = ND_IFINFO(ifp);
210 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
211 struct nd_router_advert *nd_ra;
212 struct in6_addr saddr6 = ip6->ip6_src;
213 int mcast = 0;
214 union nd_opts ndopts;
215 struct nd_defrouter *dr;
216
217 /*
218 * We only accept RAs only when
219 * the system-wide variable allows the acceptance, and
220 * per-interface variable allows RAs on the receiving interface.
221 */
222 if (ip6_accept_rtadv == 0)
223 goto freeit;
224 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV))
225 goto freeit;
226
227 if (ip6->ip6_hlim != 255) {
228 nd6log((LOG_ERR,
229 "nd6_ra_input: invalid hlim (%d) from %s to %s on %s\n",
230 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
231 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
232 goto bad;
233 }
234
235 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) {
236 nd6log((LOG_ERR,
237 "nd6_ra_input: src %s is not link-local\n",
238 ip6_sprintf(&saddr6)));
239 goto bad;
240 }
241
242 #ifndef PULLDOWN_TEST
243 IP6_EXTHDR_CHECK(m, off, icmp6len,);
244 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off);
245 #else
246 IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len);
247 if (nd_ra == NULL) {
248 icmp6stat.icp6s_tooshort++;
249 return;
250 }
251 #endif
252
253 icmp6len -= sizeof(*nd_ra);
254 nd6_option_init(nd_ra + 1, icmp6len, &ndopts);
255 if (nd6_options(&ndopts) < 0) {
256 nd6log((LOG_INFO,
257 "nd6_ra_input: invalid ND option, ignored\n"));
258 /* nd6_options have incremented stats */
259 goto freeit;
260 }
261
262 {
263 struct nd_defrouter dr0;
264 u_int32_t advreachable = nd_ra->nd_ra_reachable;
265
266 /* remember if this is a multicasted advertisement */
267 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst))
268 mcast = 1;
269
270 bzero(&dr0, sizeof(dr0));
271 dr0.rtaddr = saddr6;
272 dr0.flags = nd_ra->nd_ra_flags_reserved;
273 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime);
274 dr0.expire = time_second + dr0.rtlifetime;
275 dr0.ifp = ifp;
276 /* unspecified or not? (RFC 2461 6.3.4) */
277 if (advreachable) {
278 advreachable = ntohl(advreachable);
279 if (advreachable <= MAX_REACHABLE_TIME &&
280 ndi->basereachable != advreachable) {
281 ndi->basereachable = advreachable;
282 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable);
283 ndi->recalctm = nd6_recalc_reachtm_interval; /* reset */
284 }
285 }
286 if (nd_ra->nd_ra_retransmit)
287 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit);
288 if (nd_ra->nd_ra_curhoplimit)
289 ndi->chlim = nd_ra->nd_ra_curhoplimit;
290 dr = defrtrlist_update(&dr0);
291 }
292
293 /*
294 * prefix
295 */
296 if (ndopts.nd_opts_pi) {
297 struct nd_opt_hdr *pt;
298 struct nd_opt_prefix_info *pi = NULL;
299 struct nd_prefixctl pr;
300
301 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi;
302 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end;
303 pt = (struct nd_opt_hdr *)((caddr_t)pt +
304 (pt->nd_opt_len << 3))) {
305 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION)
306 continue;
307 pi = (struct nd_opt_prefix_info *)pt;
308
309 if (pi->nd_opt_pi_len != 4) {
310 nd6log((LOG_INFO,
311 "nd6_ra_input: invalid option "
312 "len %d for prefix information option, "
313 "ignored\n", pi->nd_opt_pi_len));
314 continue;
315 }
316
317 if (128 < pi->nd_opt_pi_prefix_len) {
318 nd6log((LOG_INFO,
319 "nd6_ra_input: invalid prefix "
320 "len %d for prefix information option, "
321 "ignored\n", pi->nd_opt_pi_prefix_len));
322 continue;
323 }
324
325 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix)
326 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) {
327 nd6log((LOG_INFO,
328 "nd6_ra_input: invalid prefix "
329 "%s, ignored\n",
330 ip6_sprintf(&pi->nd_opt_pi_prefix)));
331 continue;
332 }
333
334 bzero(&pr, sizeof(pr));
335 pr.ndpr_prefix.sin6_family = AF_INET6;
336 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix);
337 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix;
338 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif;
339
340 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved &
341 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0;
342 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved &
343 ND_OPT_PI_FLAG_AUTO) ? 1 : 0;
344 pr.ndpr_plen = pi->nd_opt_pi_prefix_len;
345 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time);
346 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time);
347 (void)prelist_update(&pr, dr, m, mcast);
348 }
349 }
350
351 /*
352 * MTU
353 */
354 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) {
355 u_long mtu;
356 u_long maxmtu;
357
358 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
359
360 /* lower bound */
361 if (mtu < IPV6_MMTU) {
362 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option "
363 "mtu=%lu sent from %s, ignoring\n",
364 mtu, ip6_sprintf(&ip6->ip6_src)));
365 goto skip;
366 }
367
368 /* upper bound */
369 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu)
370 ? ndi->maxmtu : ifp->if_mtu;
371 if (mtu <= maxmtu) {
372 int change = (ndi->linkmtu != mtu);
373
374 ndi->linkmtu = mtu;
375 if (change) /* in6_maxmtu may change */
376 in6_setmaxmtu();
377 } else {
378 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu "
379 "mtu=%lu sent from %s; "
380 "exceeds maxmtu %lu, ignoring\n",
381 mtu, ip6_sprintf(&ip6->ip6_src), maxmtu));
382 }
383 }
384
385 skip:
386
387 /*
388 * Source link layer address
389 */
390 {
391 char *lladdr = NULL;
392 int lladdrlen = 0;
393
394 if (ndopts.nd_opts_src_lladdr) {
395 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
396 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
397 }
398
399 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
400 nd6log((LOG_INFO,
401 "nd6_ra_input: lladdrlen mismatch for %s "
402 "(if %d, RA packet %d)\n", ip6_sprintf(&saddr6),
403 ifp->if_addrlen, lladdrlen - 2));
404 goto bad;
405 }
406
407 nd6_cache_lladdr(ifp, &saddr6, lladdr,
408 lladdrlen, ND_ROUTER_ADVERT, 0);
409
410 /*
411 * Installing a link-layer address might change the state of the
412 * router's neighbor cache, which might also affect our on-link
413 * detection of adveritsed prefixes.
414 */
415 pfxlist_onlink_check();
416 }
417
418 freeit:
419 m_freem(m);
420 return;
421
422 bad:
423 icmp6stat.icp6s_badra++;
424 m_freem(m);
425 }
426
427 /*
428 * default router list proccessing sub routines
429 */
430
431 /* tell the change to user processes watching the routing socket. */
432 static void
433 nd6_rtmsg(cmd, rt)
434 int cmd;
435 struct rtentry *rt;
436 {
437 struct rt_addrinfo info;
438
439 bzero((caddr_t)&info, sizeof(info));
440 info.rti_info[RTAX_DST] = rt_key(rt);
441 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
442 info.rti_info[RTAX_NETMASK] = rt_mask(rt);
443 if (rt->rt_ifp) {
444 info.rti_info[RTAX_IFP] =
445 TAILQ_FIRST(&rt->rt_ifp->if_addrlist)->ifa_addr;
446 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr;
447 }
448
449 rt_missmsg(cmd, &info, rt->rt_flags, 0);
450 }
451
452 void
453 defrouter_addreq(new)
454 struct nd_defrouter *new;
455 {
456 struct sockaddr_in6 def, mask, gate;
457 struct rtentry *newrt = NULL;
458 int s;
459 int error;
460
461 bzero(&def, sizeof(def));
462 bzero(&mask, sizeof(mask));
463 bzero(&gate, sizeof(gate));
464
465 def.sin6_len = mask.sin6_len = gate.sin6_len =
466 sizeof(struct sockaddr_in6);
467 def.sin6_family = gate.sin6_family = AF_INET6;
468 gate.sin6_addr = new->rtaddr;
469
470 s = splnet();
471 error = rtrequest(RTM_ADD, (struct sockaddr *)&def,
472 (struct sockaddr *)&gate, (struct sockaddr *)&mask,
473 RTF_GATEWAY, &newrt);
474 if (newrt) {
475 RT_LOCK(newrt);
476 nd6_rtmsg(RTM_ADD, newrt); /* tell user process */
477 RT_REMREF(newrt);
478 RT_UNLOCK(newrt);
479 }
480 if (error == 0)
481 new->installed = 1;
482 splx(s);
483 return;
484 }
485
486 struct nd_defrouter *
487 defrouter_lookup(addr, ifp)
488 struct in6_addr *addr;
489 struct ifnet *ifp;
490 {
491 struct nd_defrouter *dr;
492
493 for (dr = TAILQ_FIRST(&nd_defrouter); dr;
494 dr = TAILQ_NEXT(dr, dr_entry)) {
495 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr))
496 return (dr);
497 }
498
499 return (NULL); /* search failed */
500 }
501
502 /*
503 * Remove the default route for a given router.
504 * This is just a subroutine function for defrouter_select(), and should
505 * not be called from anywhere else.
506 */
507 static void
508 defrouter_delreq(dr)
509 struct nd_defrouter *dr;
510 {
511 struct sockaddr_in6 def, mask, gate;
512 struct rtentry *oldrt = NULL;
513
514 bzero(&def, sizeof(def));
515 bzero(&mask, sizeof(mask));
516 bzero(&gate, sizeof(gate));
517
518 def.sin6_len = mask.sin6_len = gate.sin6_len =
519 sizeof(struct sockaddr_in6);
520 def.sin6_family = gate.sin6_family = AF_INET6;
521 gate.sin6_addr = dr->rtaddr;
522
523 rtrequest(RTM_DELETE, (struct sockaddr *)&def,
524 (struct sockaddr *)&gate,
525 (struct sockaddr *)&mask, RTF_GATEWAY, &oldrt);
526 if (oldrt) {
527 nd6_rtmsg(RTM_DELETE, oldrt);
528 RTFREE(oldrt);
529 }
530
531 dr->installed = 0;
532 }
533
534 /*
535 * remove all default routes from default router list
536 */
537 void
538 defrouter_reset()
539 {
540 struct nd_defrouter *dr;
541
542 for (dr = TAILQ_FIRST(&nd_defrouter); dr;
543 dr = TAILQ_NEXT(dr, dr_entry))
544 defrouter_delreq(dr);
545
546 /*
547 * XXX should we also nuke any default routers in the kernel, by
548 * going through them by rtalloc1()?
549 */
550 }
551
552 void
553 defrtrlist_del(dr)
554 struct nd_defrouter *dr;
555 {
556 struct nd_defrouter *deldr = NULL;
557 struct nd_prefix *pr;
558
559 /*
560 * Flush all the routing table entries that use the router
561 * as a next hop.
562 */
563 if (!ip6_forwarding && ip6_accept_rtadv) /* XXX: better condition? */
564 rt6_flush(&dr->rtaddr, dr->ifp);
565
566 if (dr->installed) {
567 deldr = dr;
568 defrouter_delreq(dr);
569 }
570 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
571
572 /*
573 * Also delete all the pointers to the router in each prefix lists.
574 */
575 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
576 struct nd_pfxrouter *pfxrtr;
577 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL)
578 pfxrtr_del(pfxrtr);
579 }
580 pfxlist_onlink_check();
581
582 /*
583 * If the router is the primary one, choose a new one.
584 * Note that defrouter_select() will remove the current gateway
585 * from the routing table.
586 */
587 if (deldr)
588 defrouter_select();
589
590 free(dr, M_IP6NDP);
591 }
592
593 /*
594 * Default Router Selection according to Section 6.3.6 of RFC 2461 and
595 * draft-ietf-ipngwg-router-selection:
596 * 1) Routers that are reachable or probably reachable should be preferred.
597 * If we have more than one (probably) reachable router, prefer ones
598 * with the highest router preference.
599 * 2) When no routers on the list are known to be reachable or
600 * probably reachable, routers SHOULD be selected in a round-robin
601 * fashion, regardless of router preference values.
602 * 3) If the Default Router List is empty, assume that all
603 * destinations are on-link.
604 *
605 * We assume nd_defrouter is sorted by router preference value.
606 * Since the code below covers both with and without router preference cases,
607 * we do not need to classify the cases by ifdef.
608 *
609 * At this moment, we do not try to install more than one default router,
610 * even when the multipath routing is available, because we're not sure about
611 * the benefits for stub hosts comparing to the risk of making the code
612 * complicated and the possibility of introducing bugs.
613 */
614 void
615 defrouter_select()
616 {
617 int s = splnet();
618 struct nd_defrouter *dr, *selected_dr = NULL, *installed_dr = NULL;
619 struct rtentry *rt = NULL;
620 struct llinfo_nd6 *ln = NULL;
621
622 /*
623 * This function should be called only when acting as an autoconfigured
624 * host. Although the remaining part of this function is not effective
625 * if the node is not an autoconfigured host, we explicitly exclude
626 * such cases here for safety.
627 */
628 if (ip6_forwarding || !ip6_accept_rtadv) {
629 nd6log((LOG_WARNING,
630 "defrouter_select: called unexpectedly (forwarding=%d, "
631 "accept_rtadv=%d)\n", ip6_forwarding, ip6_accept_rtadv));
632 splx(s);
633 return;
634 }
635
636 /*
637 * Let's handle easy case (3) first:
638 * If default router list is empty, there's nothing to be done.
639 */
640 if (!TAILQ_FIRST(&nd_defrouter)) {
641 splx(s);
642 return;
643 }
644
645 /*
646 * Search for a (probably) reachable router from the list.
647 * We just pick up the first reachable one (if any), assuming that
648 * the ordering rule of the list described in defrtrlist_update().
649 */
650 for (dr = TAILQ_FIRST(&nd_defrouter); dr;
651 dr = TAILQ_NEXT(dr, dr_entry)) {
652 if (selected_dr == NULL &&
653 (rt = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) &&
654 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) &&
655 ND6_IS_LLINFO_PROBREACH(ln)) {
656 selected_dr = dr;
657 }
658
659 if (dr->installed && installed_dr == NULL)
660 installed_dr = dr;
661 else if (dr->installed && installed_dr) {
662 /* this should not happen. warn for diagnosis. */
663 log(LOG_ERR, "defrouter_select: more than one router"
664 " is installed\n");
665 }
666 }
667 /*
668 * If none of the default routers was found to be reachable,
669 * round-robin the list regardless of preference.
670 * Otherwise, if we have an installed router, check if the selected
671 * (reachable) router should really be preferred to the installed one.
672 * We only prefer the new router when the old one is not reachable
673 * or when the new one has a really higher preference value.
674 */
675 if (selected_dr == NULL) {
676 if (installed_dr == NULL || !TAILQ_NEXT(installed_dr, dr_entry))
677 selected_dr = TAILQ_FIRST(&nd_defrouter);
678 else
679 selected_dr = TAILQ_NEXT(installed_dr, dr_entry);
680 } else if (installed_dr &&
681 (rt = nd6_lookup(&installed_dr->rtaddr, 0, installed_dr->ifp)) &&
682 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) &&
683 ND6_IS_LLINFO_PROBREACH(ln) &&
684 rtpref(selected_dr) <= rtpref(installed_dr)) {
685 selected_dr = installed_dr;
686 }
687
688 /*
689 * If the selected router is different than the installed one,
690 * remove the installed router and install the selected one.
691 * Note that the selected router is never NULL here.
692 */
693 if (installed_dr != selected_dr) {
694 if (installed_dr)
695 defrouter_delreq(installed_dr);
696 defrouter_addreq(selected_dr);
697 }
698
699 splx(s);
700 return;
701 }
702
703 /*
704 * for default router selection
705 * regards router-preference field as a 2-bit signed integer
706 */
707 static int
708 rtpref(struct nd_defrouter *dr)
709 {
710 switch (dr->flags & ND_RA_FLAG_RTPREF_MASK) {
711 case ND_RA_FLAG_RTPREF_HIGH:
712 return (RTPREF_HIGH);
713 case ND_RA_FLAG_RTPREF_MEDIUM:
714 case ND_RA_FLAG_RTPREF_RSV:
715 return (RTPREF_MEDIUM);
716 case ND_RA_FLAG_RTPREF_LOW:
717 return (RTPREF_LOW);
718 default:
719 /*
720 * This case should never happen. If it did, it would mean a
721 * serious bug of kernel internal. We thus always bark here.
722 * Or, can we even panic?
723 */
724 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->flags);
725 return (RTPREF_INVALID);
726 }
727 /* NOTREACHED */
728 }
729
730 static struct nd_defrouter *
731 defrtrlist_update(new)
732 struct nd_defrouter *new;
733 {
734 struct nd_defrouter *dr, *n;
735 int s = splnet();
736
737 if ((dr = defrouter_lookup(&new->rtaddr, new->ifp)) != NULL) {
738 /* entry exists */
739 if (new->rtlifetime == 0) {
740 defrtrlist_del(dr);
741 dr = NULL;
742 } else {
743 int oldpref = rtpref(dr);
744
745 /* override */
746 dr->flags = new->flags; /* xxx flag check */
747 dr->rtlifetime = new->rtlifetime;
748 dr->expire = new->expire;
749
750 /*
751 * If the preference does not change, there's no need
752 * to sort the entries.
753 */
754 if (rtpref(new) == oldpref) {
755 splx(s);
756 return (dr);
757 }
758
759 /*
760 * preferred router may be changed, so relocate
761 * this router.
762 * XXX: calling TAILQ_REMOVE directly is a bad manner.
763 * However, since defrtrlist_del() has many side
764 * effects, we intentionally do so here.
765 * defrouter_select() below will handle routing
766 * changes later.
767 */
768 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
769 n = dr;
770 goto insert;
771 }
772 splx(s);
773 return (dr);
774 }
775
776 /* entry does not exist */
777 if (new->rtlifetime == 0) {
778 splx(s);
779 return (NULL);
780 }
781
782 n = (struct nd_defrouter *)malloc(sizeof(*n), M_IP6NDP, M_NOWAIT);
783 if (n == NULL) {
784 splx(s);
785 return (NULL);
786 }
787 bzero(n, sizeof(*n));
788 *n = *new;
789
790 insert:
791 /*
792 * Insert the new router in the Default Router List;
793 * The Default Router List should be in the descending order
794 * of router-preferece. Routers with the same preference are
795 * sorted in the arriving time order.
796 */
797
798 /* insert at the end of the group */
799 for (dr = TAILQ_FIRST(&nd_defrouter); dr;
800 dr = TAILQ_NEXT(dr, dr_entry)) {
801 if (rtpref(n) > rtpref(dr))
802 break;
803 }
804 if (dr)
805 TAILQ_INSERT_BEFORE(dr, n, dr_entry);
806 else
807 TAILQ_INSERT_TAIL(&nd_defrouter, n, dr_entry);
808
809 defrouter_select();
810
811 splx(s);
812
813 return (n);
814 }
815
816 static struct nd_pfxrouter *
817 pfxrtr_lookup(pr, dr)
818 struct nd_prefix *pr;
819 struct nd_defrouter *dr;
820 {
821 struct nd_pfxrouter *search;
822
823 for (search = pr->ndpr_advrtrs.lh_first; search; search = search->pfr_next) {
824 if (search->router == dr)
825 break;
826 }
827
828 return (search);
829 }
830
831 static void
832 pfxrtr_add(pr, dr)
833 struct nd_prefix *pr;
834 struct nd_defrouter *dr;
835 {
836 struct nd_pfxrouter *new;
837
838 new = (struct nd_pfxrouter *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT);
839 if (new == NULL)
840 return;
841 bzero(new, sizeof(*new));
842 new->router = dr;
843
844 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry);
845
846 pfxlist_onlink_check();
847 }
848
849 static void
850 pfxrtr_del(pfr)
851 struct nd_pfxrouter *pfr;
852 {
853 LIST_REMOVE(pfr, pfr_entry);
854 free(pfr, M_IP6NDP);
855 }
856
857 struct nd_prefix *
858 nd6_prefix_lookup(key)
859 struct nd_prefixctl *key;
860 {
861 struct nd_prefix *search;
862
863 for (search = nd_prefix.lh_first; search; search = search->ndpr_next) {
864 if (key->ndpr_ifp == search->ndpr_ifp &&
865 key->ndpr_plen == search->ndpr_plen &&
866 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr,
867 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) {
868 break;
869 }
870 }
871
872 return (search);
873 }
874
875 int
876 nd6_prelist_add(pr, dr, newp)
877 struct nd_prefixctl *pr;
878 struct nd_prefix **newp;
879 struct nd_defrouter *dr;
880 {
881 struct nd_prefix *new = NULL;
882 int error = 0;
883 int i, s;
884
885 new = (struct nd_prefix *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT);
886 if (new == NULL)
887 return(ENOMEM);
888 bzero(new, sizeof(*new));
889 new->ndpr_ifp = pr->ndpr_ifp;
890 new->ndpr_prefix = pr->ndpr_prefix;
891 new->ndpr_plen = pr->ndpr_plen;
892 new->ndpr_vltime = pr->ndpr_vltime;
893 new->ndpr_pltime = pr->ndpr_pltime;
894 new->ndpr_flags = pr->ndpr_flags;
895 if ((error = in6_init_prefix_ltimes(new)) != 0) {
896 free(new, M_IP6NDP);
897 return(error);
898 }
899 new->ndpr_lastupdate = time_second;
900 if (newp != NULL)
901 *newp = new;
902
903 /* initialization */
904 LIST_INIT(&new->ndpr_advrtrs);
905 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen);
906 /* make prefix in the canonical form */
907 for (i = 0; i < 4; i++)
908 new->ndpr_prefix.sin6_addr.s6_addr32[i] &=
909 new->ndpr_mask.s6_addr32[i];
910
911 s = splnet();
912 /* link ndpr_entry to nd_prefix list */
913 LIST_INSERT_HEAD(&nd_prefix, new, ndpr_entry);
914 splx(s);
915
916 /* ND_OPT_PI_FLAG_ONLINK processing */
917 if (new->ndpr_raf_onlink) {
918 int e;
919
920 if ((e = nd6_prefix_onlink(new)) != 0) {
921 nd6log((LOG_ERR, "nd6_prelist_add: failed to make "
922 "the prefix %s/%d on-link on %s (errno=%d)\n",
923 ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
924 pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
925 /* proceed anyway. XXX: is it correct? */
926 }
927 }
928
929 if (dr)
930 pfxrtr_add(new, dr);
931
932 return 0;
933 }
934
935 void
936 prelist_remove(pr)
937 struct nd_prefix *pr;
938 {
939 struct nd_pfxrouter *pfr, *next;
940 int e, s;
941
942 /* make sure to invalidate the prefix until it is really freed. */
943 pr->ndpr_vltime = 0;
944 pr->ndpr_pltime = 0;
945
946 /*
947 * Though these flags are now meaningless, we'd rather keep the value
948 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users
949 * when executing "ndp -p".
950 */
951
952 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 &&
953 (e = nd6_prefix_offlink(pr)) != 0) {
954 nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink "
955 "on %s, errno=%d\n",
956 ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
957 pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
958 /* what should we do? */
959 }
960
961 if (pr->ndpr_refcnt > 0)
962 return; /* notice here? */
963
964 s = splnet();
965
966 /* unlink ndpr_entry from nd_prefix list */
967 LIST_REMOVE(pr, ndpr_entry);
968
969 /* free list of routers that adversed the prefix */
970 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; pfr = next) {
971 next = pfr->pfr_next;
972
973 free(pfr, M_IP6NDP);
974 }
975 splx(s);
976
977 free(pr, M_IP6NDP);
978
979 pfxlist_onlink_check();
980 }
981
982 static int
983 prelist_update(new, dr, m, mcast)
984 struct nd_prefixctl *new;
985 struct nd_defrouter *dr; /* may be NULL */
986 struct mbuf *m;
987 int mcast;
988 {
989 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL;
990 struct ifaddr *ifa;
991 struct ifnet *ifp = new->ndpr_ifp;
992 struct nd_prefix *pr;
993 int s = splnet();
994 int error = 0;
995 int newprefix = 0;
996 int auth;
997 struct in6_addrlifetime lt6_tmp;
998
999 auth = 0;
1000 if (m) {
1001 /*
1002 * Authenticity for NA consists authentication for
1003 * both IP header and IP datagrams, doesn't it ?
1004 */
1005 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM)
1006 auth = ((m->m_flags & M_AUTHIPHDR) &&
1007 (m->m_flags & M_AUTHIPDGM));
1008 #endif
1009 }
1010
1011 if ((pr = nd6_prefix_lookup(new)) != NULL) {
1012 /*
1013 * nd6_prefix_lookup() ensures that pr and new have the same
1014 * prefix on a same interface.
1015 */
1016
1017 /*
1018 * Update prefix information. Note that the on-link (L) bit
1019 * and the autonomous (A) bit should NOT be changed from 1
1020 * to 0.
1021 */
1022 if (new->ndpr_raf_onlink == 1)
1023 pr->ndpr_raf_onlink = 1;
1024 if (new->ndpr_raf_auto == 1)
1025 pr->ndpr_raf_auto = 1;
1026 if (new->ndpr_raf_onlink) {
1027 pr->ndpr_vltime = new->ndpr_vltime;
1028 pr->ndpr_pltime = new->ndpr_pltime;
1029 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */
1030 pr->ndpr_lastupdate = time_second;
1031 }
1032
1033 if (new->ndpr_raf_onlink &&
1034 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
1035 int e;
1036
1037 if ((e = nd6_prefix_onlink(pr)) != 0) {
1038 nd6log((LOG_ERR,
1039 "prelist_update: failed to make "
1040 "the prefix %s/%d on-link on %s "
1041 "(errno=%d)\n",
1042 ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
1043 pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
1044 /* proceed anyway. XXX: is it correct? */
1045 }
1046 }
1047
1048 if (dr && pfxrtr_lookup(pr, dr) == NULL)
1049 pfxrtr_add(pr, dr);
1050 } else {
1051 struct nd_prefix *newpr = NULL;
1052
1053 newprefix = 1;
1054
1055 if (new->ndpr_vltime == 0)
1056 goto end;
1057 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0)
1058 goto end;
1059
1060 error = nd6_prelist_add(new, dr, &newpr);
1061 if (error != 0 || newpr == NULL) {
1062 nd6log((LOG_NOTICE, "prelist_update: "
1063 "nd6_prelist_add failed for %s/%d on %s "
1064 "errno=%d, returnpr=%p\n",
1065 ip6_sprintf(&new->ndpr_prefix.sin6_addr),
1066 new->ndpr_plen, if_name(new->ndpr_ifp),
1067 error, newpr));
1068 goto end; /* we should just give up in this case. */
1069 }
1070
1071 /*
1072 * XXX: from the ND point of view, we can ignore a prefix
1073 * with the on-link bit being zero. However, we need a
1074 * prefix structure for references from autoconfigured
1075 * addresses. Thus, we explicitly make sure that the prefix
1076 * itself expires now.
1077 */
1078 if (newpr->ndpr_raf_onlink == 0) {
1079 newpr->ndpr_vltime = 0;
1080 newpr->ndpr_pltime = 0;
1081 in6_init_prefix_ltimes(newpr);
1082 }
1083
1084 pr = newpr;
1085 }
1086
1087 /*
1088 * Address autoconfiguration based on Section 5.5.3 of RFC 2462.
1089 * Note that pr must be non NULL at this point.
1090 */
1091
1092 /* 5.5.3 (a). Ignore the prefix without the A bit set. */
1093 if (!new->ndpr_raf_auto)
1094 goto end;
1095
1096 /*
1097 * 5.5.3 (b). the link-local prefix should have been ignored in
1098 * nd6_ra_input.
1099 */
1100
1101 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */
1102 if (new->ndpr_pltime > new->ndpr_vltime) {
1103 error = EINVAL; /* XXX: won't be used */
1104 goto end;
1105 }
1106
1107 /*
1108 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of
1109 * an address configured by stateless autoconfiguration already in the
1110 * list of addresses associated with the interface, and the Valid
1111 * Lifetime is not 0, form an address. We first check if we have
1112 * a matching prefix.
1113 * Note: we apply a clarification in rfc2462bis-02 here. We only
1114 * consider autoconfigured addresses while RFC2462 simply said
1115 * "address".
1116 */
1117 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
1118 struct in6_ifaddr *ifa6;
1119 u_int32_t remaininglifetime;
1120
1121 if (ifa->ifa_addr->sa_family != AF_INET6)
1122 continue;
1123
1124 ifa6 = (struct in6_ifaddr *)ifa;
1125
1126 /*
1127 * We only consider autoconfigured addresses as per rfc2462bis.
1128 */
1129 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF))
1130 continue;
1131
1132 /*
1133 * Spec is not clear here, but I believe we should concentrate
1134 * on unicast (i.e. not anycast) addresses.
1135 * XXX: other ia6_flags? detached or duplicated?
1136 */
1137 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0)
1138 continue;
1139
1140 /*
1141 * Ignore the address if it is not associated with a prefix
1142 * or is associated with a prefix that is different from this
1143 * one. (pr is never NULL here)
1144 */
1145 if (ifa6->ia6_ndpr != pr)
1146 continue;
1147
1148 if (ia6_match == NULL) /* remember the first one */
1149 ia6_match = ifa6;
1150
1151 /*
1152 * An already autoconfigured address matched. Now that we
1153 * are sure there is at least one matched address, we can
1154 * proceed to 5.5.3. (e): update the lifetimes according to the
1155 * "two hours" rule and the privacy extension.
1156 * We apply some clarifications in rfc2462bis:
1157 * - use remaininglifetime instead of storedlifetime as a
1158 * variable name
1159 * - remove the dead code in the "two-hour" rule
1160 */
1161 #define TWOHOUR (120*60)
1162 lt6_tmp = ifa6->ia6_lifetime;
1163
1164 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME)
1165 remaininglifetime = ND6_INFINITE_LIFETIME;
1166 else if (time_second - ifa6->ia6_updatetime >
1167 lt6_tmp.ia6t_vltime) {
1168 /*
1169 * The case of "invalid" address. We should usually
1170 * not see this case.
1171 */
1172 remaininglifetime = 0;
1173 } else
1174 remaininglifetime = lt6_tmp.ia6t_vltime -
1175 (time_second - ifa6->ia6_updatetime);
1176
1177 /* when not updating, keep the current stored lifetime. */
1178 lt6_tmp.ia6t_vltime = remaininglifetime;
1179
1180 if (TWOHOUR < new->ndpr_vltime ||
1181 remaininglifetime < new->ndpr_vltime) {
1182 lt6_tmp.ia6t_vltime = new->ndpr_vltime;
1183 } else if (remaininglifetime <= TWOHOUR) {
1184 if (auth) {
1185 lt6_tmp.ia6t_vltime = new->ndpr_vltime;
1186 }
1187 } else {
1188 /*
1189 * new->ndpr_vltime <= TWOHOUR &&
1190 * TWOHOUR < remaininglifetime
1191 */
1192 lt6_tmp.ia6t_vltime = TWOHOUR;
1193 }
1194
1195 /* The 2 hour rule is not imposed for preferred lifetime. */
1196 lt6_tmp.ia6t_pltime = new->ndpr_pltime;
1197
1198 in6_init_address_ltimes(pr, <6_tmp);
1199
1200 /*
1201 * We need to treat lifetimes for temporary addresses
1202 * differently, according to
1203 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1);
1204 * we only update the lifetimes when they are in the maximum
1205 * intervals.
1206 */
1207 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
1208 u_int32_t maxvltime, maxpltime;
1209
1210 if (ip6_temp_valid_lifetime >
1211 (u_int32_t)((time_second - ifa6->ia6_createtime) +
1212 ip6_desync_factor)) {
1213 maxvltime = ip6_temp_valid_lifetime -
1214 (time_second - ifa6->ia6_createtime) -
1215 ip6_desync_factor;
1216 } else
1217 maxvltime = 0;
1218 if (ip6_temp_preferred_lifetime >
1219 (u_int32_t)((time_second - ifa6->ia6_createtime) +
1220 ip6_desync_factor)) {
1221 maxpltime = ip6_temp_preferred_lifetime -
1222 (time_second - ifa6->ia6_createtime) -
1223 ip6_desync_factor;
1224 } else
1225 maxpltime = 0;
1226
1227 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME ||
1228 lt6_tmp.ia6t_vltime > maxvltime) {
1229 lt6_tmp.ia6t_vltime = maxvltime;
1230 }
1231 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME ||
1232 lt6_tmp.ia6t_pltime > maxpltime) {
1233 lt6_tmp.ia6t_pltime = maxpltime;
1234 }
1235 }
1236 ifa6->ia6_lifetime = lt6_tmp;
1237 ifa6->ia6_updatetime = time_second;
1238 }
1239 if (ia6_match == NULL && new->ndpr_vltime) {
1240 int ifidlen;
1241
1242 /*
1243 * 5.5.3 (d) (continued)
1244 * No address matched and the valid lifetime is non-zero.
1245 * Create a new address.
1246 */
1247
1248 /*
1249 * Prefix Length check:
1250 * If the sum of the prefix length and interface identifier
1251 * length does not equal 128 bits, the Prefix Information
1252 * option MUST be ignored. The length of the interface
1253 * identifier is defined in a separate link-type specific
1254 * document.
1255 */
1256 ifidlen = in6_if2idlen(ifp);
1257 if (ifidlen < 0) {
1258 /* this should not happen, so we always log it. */
1259 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n",
1260 if_name(ifp));
1261 goto end;
1262 }
1263 if (ifidlen + pr->ndpr_plen != 128) {
1264 nd6log((LOG_INFO,
1265 "prelist_update: invalid prefixlen "
1266 "%d for %s, ignored\n",
1267 pr->ndpr_plen, if_name(ifp)));
1268 goto end;
1269 }
1270
1271 if ((ia6 = in6_ifadd(new, mcast)) != NULL) {
1272 /*
1273 * note that we should use pr (not new) for reference.
1274 */
1275 pr->ndpr_refcnt++;
1276 ia6->ia6_ndpr = pr;
1277
1278 /*
1279 * RFC 3041 3.3 (2).
1280 * When a new public address is created as described
1281 * in RFC2462, also create a new temporary address.
1282 *
1283 * RFC 3041 3.5.
1284 * When an interface connects to a new link, a new
1285 * randomized interface identifier should be generated
1286 * immediately together with a new set of temporary
1287 * addresses. Thus, we specifiy 1 as the 2nd arg of
1288 * in6_tmpifadd().
1289 */
1290 if (ip6_use_tempaddr) {
1291 int e;
1292 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) {
1293 nd6log((LOG_NOTICE, "prelist_update: "
1294 "failed to create a temporary "
1295 "address, errno=%d\n",
1296 e));
1297 }
1298 }
1299
1300 /*
1301 * A newly added address might affect the status
1302 * of other addresses, so we check and update it.
1303 * XXX: what if address duplication happens?
1304 */
1305 pfxlist_onlink_check();
1306 } else {
1307 /* just set an error. do not bark here. */
1308 error = EADDRNOTAVAIL; /* XXX: might be unused. */
1309 }
1310 }
1311
1312 end:
1313 splx(s);
1314 return error;
1315 }
1316
1317 /*
1318 * A supplement function used in the on-link detection below;
1319 * detect if a given prefix has a (probably) reachable advertising router.
1320 * XXX: lengthy function name...
1321 */
1322 static struct nd_pfxrouter *
1323 find_pfxlist_reachable_router(pr)
1324 struct nd_prefix *pr;
1325 {
1326 struct nd_pfxrouter *pfxrtr;
1327 struct rtentry *rt;
1328 struct llinfo_nd6 *ln;
1329
1330 for (pfxrtr = LIST_FIRST(&pr->ndpr_advrtrs); pfxrtr;
1331 pfxrtr = LIST_NEXT(pfxrtr, pfr_entry)) {
1332 if ((rt = nd6_lookup(&pfxrtr->router->rtaddr, 0,
1333 pfxrtr->router->ifp)) &&
1334 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) &&
1335 ND6_IS_LLINFO_PROBREACH(ln))
1336 break; /* found */
1337 }
1338
1339 return (pfxrtr);
1340 }
1341
1342 /*
1343 * Check if each prefix in the prefix list has at least one available router
1344 * that advertised the prefix (a router is "available" if its neighbor cache
1345 * entry is reachable or probably reachable).
1346 * If the check fails, the prefix may be off-link, because, for example,
1347 * we have moved from the network but the lifetime of the prefix has not
1348 * expired yet. So we should not use the prefix if there is another prefix
1349 * that has an available router.
1350 * But, if there is no prefix that has an available router, we still regards
1351 * all the prefixes as on-link. This is because we can't tell if all the
1352 * routers are simply dead or if we really moved from the network and there
1353 * is no router around us.
1354 */
1355 void
1356 pfxlist_onlink_check()
1357 {
1358 struct nd_prefix *pr;
1359 struct in6_ifaddr *ifa;
1360 struct nd_defrouter *dr;
1361 struct nd_pfxrouter *pfxrtr = NULL;
1362
1363 /*
1364 * Check if there is a prefix that has a reachable advertising
1365 * router.
1366 */
1367 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
1368 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr))
1369 break;
1370 }
1371
1372 /*
1373 * If we have no such prefix, check whether we still have a router
1374 * that does not advertise any prefixes.
1375 */
1376 if (pr == NULL) {
1377 for (dr = TAILQ_FIRST(&nd_defrouter); dr;
1378 dr = TAILQ_NEXT(dr, dr_entry)) {
1379 struct nd_prefix *pr0;
1380
1381 for (pr0 = nd_prefix.lh_first; pr0;
1382 pr0 = pr0->ndpr_next) {
1383 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL)
1384 break;
1385 }
1386 if (pfxrtr != NULL)
1387 break;
1388 }
1389 }
1390 if (pr != NULL || (TAILQ_FIRST(&nd_defrouter) && pfxrtr == NULL)) {
1391 /*
1392 * There is at least one prefix that has a reachable router,
1393 * or at least a router which probably does not advertise
1394 * any prefixes. The latter would be the case when we move
1395 * to a new link where we have a router that does not provide
1396 * prefixes and we configure an address by hand.
1397 * Detach prefixes which have no reachable advertising
1398 * router, and attach other prefixes.
1399 */
1400 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
1401 /* XXX: a link-local prefix should never be detached */
1402 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1403 continue;
1404
1405 /*
1406 * we aren't interested in prefixes without the L bit
1407 * set.
1408 */
1409 if (pr->ndpr_raf_onlink == 0)
1410 continue;
1411
1412 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 &&
1413 find_pfxlist_reachable_router(pr) == NULL)
1414 pr->ndpr_stateflags |= NDPRF_DETACHED;
1415 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 &&
1416 find_pfxlist_reachable_router(pr) != 0)
1417 pr->ndpr_stateflags &= ~NDPRF_DETACHED;
1418 }
1419 } else {
1420 /* there is no prefix that has a reachable router */
1421 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
1422 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1423 continue;
1424
1425 if (pr->ndpr_raf_onlink == 0)
1426 continue;
1427
1428 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0)
1429 pr->ndpr_stateflags &= ~NDPRF_DETACHED;
1430 }
1431 }
1432
1433 /*
1434 * Remove each interface route associated with a (just) detached
1435 * prefix, and reinstall the interface route for a (just) attached
1436 * prefix. Note that all attempt of reinstallation does not
1437 * necessarily success, when a same prefix is shared among multiple
1438 * interfaces. Such cases will be handled in nd6_prefix_onlink,
1439 * so we don't have to care about them.
1440 */
1441 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
1442 int e;
1443
1444 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1445 continue;
1446
1447 if (pr->ndpr_raf_onlink == 0)
1448 continue;
1449
1450 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 &&
1451 (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
1452 if ((e = nd6_prefix_offlink(pr)) != 0) {
1453 nd6log((LOG_ERR,
1454 "pfxlist_onlink_check: failed to "
1455 "make %s/%d offlink, errno=%d\n",
1456 ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
1457 pr->ndpr_plen, e));
1458 }
1459 }
1460 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 &&
1461 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 &&
1462 pr->ndpr_raf_onlink) {
1463 if ((e = nd6_prefix_onlink(pr)) != 0) {
1464 nd6log((LOG_ERR,
1465 "pfxlist_onlink_check: failed to "
1466 "make %s/%d onlink, errno=%d\n",
1467 ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
1468 pr->ndpr_plen, e));
1469 }
1470 }
1471 }
1472
1473 /*
1474 * Changes on the prefix status might affect address status as well.
1475 * Make sure that all addresses derived from an attached prefix are
1476 * attached, and that all addresses derived from a detached prefix are
1477 * detached. Note, however, that a manually configured address should
1478 * always be attached.
1479 * The precise detection logic is same as the one for prefixes.
1480 */
1481 for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) {
1482 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF))
1483 continue;
1484
1485 if (ifa->ia6_ndpr == NULL) {
1486 /*
1487 * This can happen when we first configure the address
1488 * (i.e. the address exists, but the prefix does not).
1489 * XXX: complicated relationships...
1490 */
1491 continue;
1492 }
1493
1494 if (find_pfxlist_reachable_router(ifa->ia6_ndpr))
1495 break;
1496 }
1497 if (ifa) {
1498 for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) {
1499 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1500 continue;
1501
1502 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */
1503 continue;
1504
1505 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) {
1506 if (ifa->ia6_flags & IN6_IFF_DETACHED) {
1507 ifa->ia6_flags &= ~IN6_IFF_DETACHED;
1508 ifa->ia6_flags |= IN6_IFF_TENTATIVE;
1509 nd6_dad_start((struct ifaddr *)ifa, 0);
1510 }
1511 } else {
1512 ifa->ia6_flags |= IN6_IFF_DETACHED;
1513 }
1514 }
1515 }
1516 else {
1517 for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) {
1518 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1519 continue;
1520
1521 if (ifa->ia6_flags & IN6_IFF_DETACHED) {
1522 ifa->ia6_flags &= ~IN6_IFF_DETACHED;
1523 ifa->ia6_flags |= IN6_IFF_TENTATIVE;
1524 /* Do we need a delay in this case? */
1525 nd6_dad_start((struct ifaddr *)ifa, 0);
1526 }
1527 }
1528 }
1529 }
1530
1531 int
1532 nd6_prefix_onlink(pr)
1533 struct nd_prefix *pr;
1534 {
1535 struct ifaddr *ifa;
1536 struct ifnet *ifp = pr->ndpr_ifp;
1537 struct sockaddr_in6 mask6;
1538 struct nd_prefix *opr;
1539 u_long rtflags;
1540 int error = 0;
1541 struct rtentry *rt = NULL;
1542
1543 /* sanity check */
1544 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
1545 nd6log((LOG_ERR,
1546 "nd6_prefix_onlink: %s/%d is already on-link\n",
1547 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), pr->ndpr_plen));
1548 return (EEXIST);
1549 }
1550
1551 /*
1552 * Add the interface route associated with the prefix. Before
1553 * installing the route, check if there's the same prefix on another
1554 * interface, and the prefix has already installed the interface route.
1555 * Although such a configuration is expected to be rare, we explicitly
1556 * allow it.
1557 */
1558 for (opr = nd_prefix.lh_first; opr; opr = opr->ndpr_next) {
1559 if (opr == pr)
1560 continue;
1561
1562 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0)
1563 continue;
1564
1565 if (opr->ndpr_plen == pr->ndpr_plen &&
1566 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
1567 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen))
1568 return (0);
1569 }
1570
1571 /*
1572 * We prefer link-local addresses as the associated interface address.
1573 */
1574 /* search for a link-local addr */
1575 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
1576 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST);
1577 if (ifa == NULL) {
1578 /* XXX: freebsd does not have ifa_ifwithaf */
1579 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
1580 if (ifa->ifa_addr->sa_family == AF_INET6)
1581 break;
1582 }
1583 /* should we care about ia6_flags? */
1584 }
1585 if (ifa == NULL) {
1586 /*
1587 * This can still happen, when, for example, we receive an RA
1588 * containing a prefix with the L bit set and the A bit clear,
1589 * after removing all IPv6 addresses on the receiving
1590 * interface. This should, of course, be rare though.
1591 */
1592 nd6log((LOG_NOTICE,
1593 "nd6_prefix_onlink: failed to find any ifaddr"
1594 " to add route for a prefix(%s/%d) on %s\n",
1595 ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
1596 pr->ndpr_plen, if_name(ifp)));
1597 return (0);
1598 }
1599
1600 /*
1601 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs.
1602 * ifa->ifa_rtrequest = nd6_rtrequest;
1603 */
1604 bzero(&mask6, sizeof(mask6));
1605 mask6.sin6_len = sizeof(mask6);
1606 mask6.sin6_addr = pr->ndpr_mask;
1607 rtflags = ifa->ifa_flags | RTF_CLONING | RTF_UP;
1608 if (nd6_need_cache(ifp)) {
1609 /* explicitly set in case ifa_flags does not set the flag. */
1610 rtflags |= RTF_CLONING;
1611 } else {
1612 /*
1613 * explicitly clear the cloning bit in case ifa_flags sets it.
1614 */
1615 rtflags &= ~RTF_CLONING;
1616 }
1617 error = rtrequest(RTM_ADD, (struct sockaddr *)&pr->ndpr_prefix,
1618 ifa->ifa_addr, (struct sockaddr *)&mask6, rtflags, &rt);
1619 if (error == 0) {
1620 if (rt != NULL) /* this should be non NULL, though */
1621 nd6_rtmsg(RTM_ADD, rt);
1622 pr->ndpr_stateflags |= NDPRF_ONLINK;
1623 } else {
1624 nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add route for a"
1625 " prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx "
1626 "errno = %d\n",
1627 ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
1628 pr->ndpr_plen, if_name(ifp),
1629 ip6_sprintf(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr),
1630 ip6_sprintf(&mask6.sin6_addr), rtflags, error));
1631 }
1632
1633 if (rt != NULL) {
1634 RT_LOCK(rt);
1635 RT_REMREF(rt);
1636 RT_UNLOCK(rt);
1637 }
1638
1639 return (error);
1640 }
1641
1642 int
1643 nd6_prefix_offlink(pr)
1644 struct nd_prefix *pr;
1645 {
1646 int error = 0;
1647 struct ifnet *ifp = pr->ndpr_ifp;
1648 struct nd_prefix *opr;
1649 struct sockaddr_in6 sa6, mask6;
1650 struct rtentry *rt = NULL;
1651
1652 /* sanity check */
1653 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
1654 nd6log((LOG_ERR,
1655 "nd6_prefix_offlink: %s/%d is already off-link\n",
1656 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), pr->ndpr_plen));
1657 return (EEXIST);
1658 }
1659
1660 bzero(&sa6, sizeof(sa6));
1661 sa6.sin6_family = AF_INET6;
1662 sa6.sin6_len = sizeof(sa6);
1663 bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr,
1664 sizeof(struct in6_addr));
1665 bzero(&mask6, sizeof(mask6));
1666 mask6.sin6_family = AF_INET6;
1667 mask6.sin6_len = sizeof(sa6);
1668 bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr));
1669 error = rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL,
1670 (struct sockaddr *)&mask6, 0, &rt);
1671 if (error == 0) {
1672 pr->ndpr_stateflags &= ~NDPRF_ONLINK;
1673
1674 /* report the route deletion to the routing socket. */
1675 if (rt != NULL)
1676 nd6_rtmsg(RTM_DELETE, rt);
1677
1678 /*
1679 * There might be the same prefix on another interface,
1680 * the prefix which could not be on-link just because we have
1681 * the interface route (see comments in nd6_prefix_onlink).
1682 * If there's one, try to make the prefix on-link on the
1683 * interface.
1684 */
1685 for (opr = nd_prefix.lh_first; opr; opr = opr->ndpr_next) {
1686 if (opr == pr)
1687 continue;
1688
1689 if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0)
1690 continue;
1691
1692 /*
1693 * KAME specific: detached prefixes should not be
1694 * on-link.
1695 */
1696 if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0)
1697 continue;
1698
1699 if (opr->ndpr_plen == pr->ndpr_plen &&
1700 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
1701 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) {
1702 int e;
1703
1704 if ((e = nd6_prefix_onlink(opr)) != 0) {
1705 nd6log((LOG_ERR,
1706 "nd6_prefix_offlink: failed to "
1707 "recover a prefix %s/%d from %s "
1708 "to %s (errno = %d)\n",
1709 ip6_sprintf(&opr->ndpr_prefix.sin6_addr),
1710 opr->ndpr_plen, if_name(ifp),
1711 if_name(opr->ndpr_ifp), e));
1712 }
1713 }
1714 }
1715 } else {
1716 /* XXX: can we still set the NDPRF_ONLINK flag? */
1717 nd6log((LOG_ERR,
1718 "nd6_prefix_offlink: failed to delete route: "
1719 "%s/%d on %s (errno = %d)\n",
1720 ip6_sprintf(&sa6.sin6_addr), pr->ndpr_plen, if_name(ifp),
1721 error));
1722 }
1723
1724 if (rt != NULL) {
1725 RTFREE(rt);
1726 }
1727
1728 return (error);
1729 }
1730
1731 static struct in6_ifaddr *
1732 in6_ifadd(pr, mcast)
1733 struct nd_prefixctl *pr;
1734 int mcast;
1735 {
1736 struct ifnet *ifp = pr->ndpr_ifp;
1737 struct ifaddr *ifa;
1738 struct in6_aliasreq ifra;
1739 struct in6_ifaddr *ia, *ib;
1740 int error, plen0;
1741 struct in6_addr mask;
1742 int prefixlen = pr->ndpr_plen;
1743 int updateflags;
1744
1745 in6_prefixlen2mask(&mask, prefixlen);
1746
1747 /*
1748 * find a link-local address (will be interface ID).
1749 * Is it really mandatory? Theoretically, a global or a site-local
1750 * address can be configured without a link-local address, if we
1751 * have a unique interface identifier...
1752 *
1753 * it is not mandatory to have a link-local address, we can generate
1754 * interface identifier on the fly. we do this because:
1755 * (1) it should be the easiest way to find interface identifier.
1756 * (2) RFC2462 5.4 suggesting the use of the same interface identifier
1757 * for multiple addresses on a single interface, and possible shortcut
1758 * of DAD. we omitted DAD for this reason in the past.
1759 * (3) a user can prevent autoconfiguration of global address
1760 * by removing link-local address by hand (this is partly because we
1761 * don't have other way to control the use of IPv6 on an interface.
1762 * this has been our design choice - cf. NRL's "ifconfig auto").
1763 * (4) it is easier to manage when an interface has addresses
1764 * with the same interface identifier, than to have multiple addresses
1765 * with different interface identifiers.
1766 */
1767 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */
1768 if (ifa)
1769 ib = (struct in6_ifaddr *)ifa;
1770 else
1771 return NULL;
1772
1773 /* prefixlen + ifidlen must be equal to 128 */
1774 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL);
1775 if (prefixlen != plen0) {
1776 nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s "
1777 "(prefix=%d ifid=%d)\n",
1778 if_name(ifp), prefixlen, 128 - plen0));
1779 return NULL;
1780 }
1781
1782 /* make ifaddr */
1783
1784 bzero(&ifra, sizeof(ifra));
1785 /*
1786 * in6_update_ifa() does not use ifra_name, but we accurately set it
1787 * for safety.
1788 */
1789 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
1790 ifra.ifra_addr.sin6_family = AF_INET6;
1791 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
1792 /* prefix */
1793 ifra.ifra_addr.sin6_addr = pr->ndpr_prefix.sin6_addr;
1794 ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0];
1795 ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1];
1796 ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2];
1797 ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3];
1798
1799 /* interface ID */
1800 ifra.ifra_addr.sin6_addr.s6_addr32[0] |=
1801 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]);
1802 ifra.ifra_addr.sin6_addr.s6_addr32[1] |=
1803 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]);
1804 ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
1805 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]);
1806 ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
1807 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]);
1808
1809 /* new prefix mask. */
1810 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
1811 ifra.ifra_prefixmask.sin6_family = AF_INET6;
1812 bcopy(&mask, &ifra.ifra_prefixmask.sin6_addr,
1813 sizeof(ifra.ifra_prefixmask.sin6_addr));
1814
1815 /* lifetimes. */
1816 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime;
1817 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime;
1818
1819 /* XXX: scope zone ID? */
1820
1821 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */
1822
1823 /*
1824 * Make sure that we do not have this address already. This should
1825 * usually not happen, but we can still see this case, e.g., if we
1826 * have manually configured the exact address to be configured.
1827 */
1828 if (in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr) != NULL) {
1829 /* this should be rare enough to make an explicit log */
1830 log(LOG_INFO, "in6_ifadd: %s is already configured\n",
1831 ip6_sprintf(&ifra.ifra_addr.sin6_addr));
1832 return (NULL);
1833 }
1834
1835 /*
1836 * Allocate ifaddr structure, link into chain, etc.
1837 * If we are going to create a new address upon receiving a multicasted
1838 * RA, we need to impose a random delay before starting DAD.
1839 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2]
1840 */
1841 updateflags = 0;
1842 if (mcast)
1843 updateflags |= IN6_IFAUPDATE_DADDELAY;
1844 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) {
1845 nd6log((LOG_ERR,
1846 "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n",
1847 ip6_sprintf(&ifra.ifra_addr.sin6_addr), if_name(ifp),
1848 error));
1849 return (NULL); /* ifaddr must not have been allocated. */
1850 }
1851
1852 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
1853
1854 return (ia); /* this is always non-NULL */
1855 }
1856
1857 int
1858 in6_tmpifadd(ia0, forcegen, delay)
1859 const struct in6_ifaddr *ia0; /* corresponding public address */
1860 int forcegen, delay;
1861 {
1862 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp;
1863 struct in6_ifaddr *newia, *ia;
1864 struct in6_aliasreq ifra;
1865 int i, error;
1866 int trylimit = 3; /* XXX: adhoc value */
1867 int updateflags;
1868 u_int32_t randid[2];
1869 time_t vltime0, pltime0;
1870
1871 bzero(&ifra, sizeof(ifra));
1872 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
1873 ifra.ifra_addr = ia0->ia_addr;
1874 /* copy prefix mask */
1875 ifra.ifra_prefixmask = ia0->ia_prefixmask;
1876 /* clear the old IFID */
1877 for (i = 0; i < 4; i++) {
1878 ifra.ifra_addr.sin6_addr.s6_addr32[i] &=
1879 ifra.ifra_prefixmask.sin6_addr.s6_addr32[i];
1880 }
1881
1882 again:
1883 if (in6_get_tmpifid(ifp, (u_int8_t *)randid,
1884 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) {
1885 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good "
1886 "random IFID\n"));
1887 return (EINVAL);
1888 }
1889 ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
1890 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2]));
1891 ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
1892 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3]));
1893
1894 /*
1895 * in6_get_tmpifid() quite likely provided a unique interface ID.
1896 * However, we may still have a chance to see collision, because
1897 * there may be a time lag between generation of the ID and generation
1898 * of the address. So, we'll do one more sanity check.
1899 */
1900 for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1901 if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
1902 &ifra.ifra_addr.sin6_addr)) {
1903 if (trylimit-- == 0) {
1904 /*
1905 * Give up. Something strange should have
1906 * happened.
1907 */
1908 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to "
1909 "find a unique random IFID\n"));
1910 return (EEXIST);
1911 }
1912 forcegen = 1;
1913 goto again;
1914 }
1915 }
1916
1917 /*
1918 * The Valid Lifetime is the lower of the Valid Lifetime of the
1919 * public address or TEMP_VALID_LIFETIME.
1920 * The Preferred Lifetime is the lower of the Preferred Lifetime
1921 * of the public address or TEMP_PREFERRED_LIFETIME -
1922 * DESYNC_FACTOR.
1923 */
1924 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
1925 vltime0 = IFA6_IS_INVALID(ia0) ? 0 :
1926 (ia0->ia6_lifetime.ia6t_vltime -
1927 (time_second - ia0->ia6_updatetime));
1928 if (vltime0 > ip6_temp_valid_lifetime)
1929 vltime0 = ip6_temp_valid_lifetime;
1930 } else
1931 vltime0 = ip6_temp_valid_lifetime;
1932 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
1933 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 :
1934 (ia0->ia6_lifetime.ia6t_pltime -
1935 (time_second - ia0->ia6_updatetime));
1936 if (pltime0 > ip6_temp_preferred_lifetime - ip6_desync_factor){
1937 pltime0 = ip6_temp_preferred_lifetime -
1938 ip6_desync_factor;
1939 }
1940 } else
1941 pltime0 = ip6_temp_preferred_lifetime - ip6_desync_factor;
1942 ifra.ifra_lifetime.ia6t_vltime = vltime0;
1943 ifra.ifra_lifetime.ia6t_pltime = pltime0;
1944
1945 /*
1946 * A temporary address is created only if this calculated Preferred
1947 * Lifetime is greater than REGEN_ADVANCE time units.
1948 */
1949 if (ifra.ifra_lifetime.ia6t_pltime <= ip6_temp_regen_advance)
1950 return (0);
1951
1952 /* XXX: scope zone ID? */
1953
1954 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY);
1955
1956 /* allocate ifaddr structure, link into chain, etc. */
1957 updateflags = 0;
1958 if (delay)
1959 updateflags |= IN6_IFAUPDATE_DADDELAY;
1960 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0)
1961 return (error);
1962
1963 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
1964 if (newia == NULL) { /* XXX: can it happen? */
1965 nd6log((LOG_ERR,
1966 "in6_tmpifadd: ifa update succeeded, but we got "
1967 "no ifaddr\n"));
1968 return (EINVAL); /* XXX */
1969 }
1970 newia->ia6_ndpr = ia0->ia6_ndpr;
1971 newia->ia6_ndpr->ndpr_refcnt++;
1972
1973 /*
1974 * A newly added address might affect the status of other addresses.
1975 * XXX: when the temporary address is generated with a new public
1976 * address, the onlink check is redundant. However, it would be safe
1977 * to do the check explicitly everywhere a new address is generated,
1978 * and, in fact, we surely need the check when we create a new
1979 * temporary address due to deprecation of an old temporary address.
1980 */
1981 pfxlist_onlink_check();
1982
1983 return (0);
1984 }
1985
1986 static int
1987 in6_init_prefix_ltimes(struct nd_prefix *ndpr)
1988 {
1989 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME)
1990 ndpr->ndpr_preferred = 0;
1991 else
1992 ndpr->ndpr_preferred = time_second + ndpr->ndpr_pltime;
1993 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME)
1994 ndpr->ndpr_expire = 0;
1995 else
1996 ndpr->ndpr_expire = time_second + ndpr->ndpr_vltime;
1997
1998 return 0;
1999 }
2000
2001 static void
2002 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6)
2003 {
2004 /* init ia6t_expire */
2005 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME)
2006 lt6->ia6t_expire = 0;
2007 else {
2008 lt6->ia6t_expire = time_second;
2009 lt6->ia6t_expire += lt6->ia6t_vltime;
2010 }
2011
2012 /* init ia6t_preferred */
2013 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME)
2014 lt6->ia6t_preferred = 0;
2015 else {
2016 lt6->ia6t_preferred = time_second;
2017 lt6->ia6t_preferred += lt6->ia6t_pltime;
2018 }
2019 }
2020
2021 /*
2022 * Delete all the routing table entries that use the specified gateway.
2023 * XXX: this function causes search through all entries of routing table, so
2024 * it shouldn't be called when acting as a router.
2025 */
2026 void
2027 rt6_flush(gateway, ifp)
2028 struct in6_addr *gateway;
2029 struct ifnet *ifp;
2030 {
2031 struct radix_node_head *rnh = rt_tables[AF_INET6];
2032 int s = splnet();
2033
2034 /* We'll care only link-local addresses */
2035 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) {
2036 splx(s);
2037 return;
2038 }
2039
2040 RADIX_NODE_HEAD_LOCK(rnh);
2041 rnh->rnh_walktree(rnh, rt6_deleteroute, (void *)gateway);
2042 RADIX_NODE_HEAD_UNLOCK(rnh);
2043 splx(s);
2044 }
2045
2046 static int
2047 rt6_deleteroute(rn, arg)
2048 struct radix_node *rn;
2049 void *arg;
2050 {
2051 #define SIN6(s) ((struct sockaddr_in6 *)s)
2052 struct rtentry *rt = (struct rtentry *)rn;
2053 struct in6_addr *gate = (struct in6_addr *)arg;
2054
2055 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6)
2056 return (0);
2057
2058 if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) {
2059 return (0);
2060 }
2061
2062 /*
2063 * Do not delete a static route.
2064 * XXX: this seems to be a bit ad-hoc. Should we consider the
2065 * 'cloned' bit instead?
2066 */
2067 if ((rt->rt_flags & RTF_STATIC) != 0)
2068 return (0);
2069
2070 /*
2071 * We delete only host route. This means, in particular, we don't
2072 * delete default route.
2073 */
2074 if ((rt->rt_flags & RTF_HOST) == 0)
2075 return (0);
2076
2077 return (rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
2078 rt_mask(rt), rt->rt_flags, 0));
2079 #undef SIN6
2080 }
2081
2082 int
2083 nd6_setdefaultiface(ifindex)
2084 int ifindex;
2085 {
2086 int error = 0;
2087
2088 if (ifindex < 0 || if_index < ifindex)
2089 return (EINVAL);
2090 if (ifindex != 0 && !ifnet_byindex(ifindex))
2091 return (EINVAL);
2092
2093 if (nd6_defifindex != ifindex) {
2094 nd6_defifindex = ifindex;
2095 if (nd6_defifindex > 0)
2096 nd6_defifp = ifnet_byindex(nd6_defifindex);
2097 else
2098 nd6_defifp = NULL;
2099
2100 /*
2101 * Our current implementation assumes one-to-one maping between
2102 * interfaces and links, so it would be natural to use the
2103 * default interface as the default link.
2104 */
2105 scope6_setdefault(nd6_defifp);
2106 }
2107
2108 return (error);
2109 }
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