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sys/netinet6/nd6_rtr.c
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1 /* $FreeBSD: releng/6.2/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 }
Cache object: ba6462dd4973627e78947bb3229317bc
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