nd6_rtr.c revision 185348
1/*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: nd6_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $ 30 */ 31 32#include <sys/cdefs.h> 33__FBSDID("$FreeBSD: head/sys/netinet6/nd6_rtr.c 185348 2008-11-26 22:32:07Z zec $"); 34 35#include "opt_inet.h" 36#include "opt_inet6.h" 37 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/malloc.h> 41#include <sys/mbuf.h> 42#include <sys/socket.h> 43#include <sys/sockio.h> 44#include <sys/time.h> 45#include <sys/kernel.h> 46#include <sys/errno.h> 47#include <sys/syslog.h> 48#include <sys/queue.h> 49#include <sys/vimage.h> 50 51#include <net/if.h> 52#include <net/if_types.h> 53#include <net/if_dl.h> 54#include <net/route.h> 55#include <net/radix.h> 56 57#include <netinet/in.h> 58#include <netinet6/in6_var.h> 59#include <netinet6/in6_ifattach.h> 60#include <netinet/ip6.h> 61#include <netinet6/ip6_var.h> 62#include <netinet6/nd6.h> 63#include <netinet/icmp6.h> 64#include <netinet6/scope6_var.h> 65 66#define SDL(s) ((struct sockaddr_dl *)s) 67 68static int rtpref(struct nd_defrouter *); 69static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 70static int prelist_update __P((struct nd_prefixctl *, struct nd_defrouter *, 71 struct mbuf *, int)); 72static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int); 73static struct nd_pfxrouter *pfxrtr_lookup __P((struct nd_prefix *, 74 struct nd_defrouter *)); 75static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *); 76static void pfxrtr_del(struct nd_pfxrouter *); 77static struct nd_pfxrouter *find_pfxlist_reachable_router 78(struct nd_prefix *); 79static void defrouter_delreq(struct nd_defrouter *); 80static void nd6_rtmsg(int, struct rtentry *); 81 82static int in6_init_prefix_ltimes(struct nd_prefix *); 83static void in6_init_address_ltimes __P((struct nd_prefix *, 84 struct in6_addrlifetime *)); 85 86static int rt6_deleteroute(struct radix_node *, void *); 87 88#ifdef VIMAGE_GLOBALS 89extern int nd6_recalc_reachtm_interval; 90 91static struct ifnet *nd6_defifp; 92int nd6_defifindex; 93 94int ip6_use_tempaddr; 95int ip6_desync_factor; 96u_int32_t ip6_temp_preferred_lifetime; 97u_int32_t ip6_temp_valid_lifetime; 98int ip6_temp_regen_advance; 99#endif 100 101/* RTPREF_MEDIUM has to be 0! */ 102#define RTPREF_HIGH 1 103#define RTPREF_MEDIUM 0 104#define RTPREF_LOW (-1) 105#define RTPREF_RESERVED (-2) 106#define RTPREF_INVALID (-3) /* internal */ 107 108/* 109 * Receive Router Solicitation Message - just for routers. 110 * Router solicitation/advertisement is mostly managed by userland program 111 * (rtadvd) so here we have no function like nd6_ra_output(). 112 * 113 * Based on RFC 2461 114 */ 115void 116nd6_rs_input(struct mbuf *m, int off, int icmp6len) 117{ 118 INIT_VNET_INET6(curvnet); 119 struct ifnet *ifp = m->m_pkthdr.rcvif; 120 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 121 struct nd_router_solicit *nd_rs; 122 struct in6_addr saddr6 = ip6->ip6_src; 123 char *lladdr = NULL; 124 int lladdrlen = 0; 125 union nd_opts ndopts; 126 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 127 128 /* If I'm not a router, ignore it. */ 129 if (V_ip6_accept_rtadv != 0 || V_ip6_forwarding != 1) 130 goto freeit; 131 132 /* Sanity checks */ 133 if (ip6->ip6_hlim != 255) { 134 nd6log((LOG_ERR, 135 "nd6_rs_input: invalid hlim (%d) from %s to %s on %s\n", 136 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 137 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 138 goto bad; 139 } 140 141 /* 142 * Don't update the neighbor cache, if src = ::. 143 * This indicates that the src has no IP address assigned yet. 144 */ 145 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 146 goto freeit; 147 148#ifndef PULLDOWN_TEST 149 IP6_EXTHDR_CHECK(m, off, icmp6len,); 150 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off); 151#else 152 IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len); 153 if (nd_rs == NULL) { 154 V_icmp6stat.icp6s_tooshort++; 155 return; 156 } 157#endif 158 159 icmp6len -= sizeof(*nd_rs); 160 nd6_option_init(nd_rs + 1, icmp6len, &ndopts); 161 if (nd6_options(&ndopts) < 0) { 162 nd6log((LOG_INFO, 163 "nd6_rs_input: invalid ND option, ignored\n")); 164 /* nd6_options have incremented stats */ 165 goto freeit; 166 } 167 168 if (ndopts.nd_opts_src_lladdr) { 169 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 170 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 171 } 172 173 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 174 nd6log((LOG_INFO, 175 "nd6_rs_input: lladdrlen mismatch for %s " 176 "(if %d, RS packet %d)\n", 177 ip6_sprintf(ip6bufs, &saddr6), 178 ifp->if_addrlen, lladdrlen - 2)); 179 goto bad; 180 } 181 182 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0); 183 184 freeit: 185 m_freem(m); 186 return; 187 188 bad: 189 V_icmp6stat.icp6s_badrs++; 190 m_freem(m); 191} 192 193/* 194 * Receive Router Advertisement Message. 195 * 196 * Based on RFC 2461 197 * TODO: on-link bit on prefix information 198 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing 199 */ 200void 201nd6_ra_input(struct mbuf *m, int off, int icmp6len) 202{ 203 INIT_VNET_INET6(curvnet); 204 struct ifnet *ifp = m->m_pkthdr.rcvif; 205 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 206 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 207 struct nd_router_advert *nd_ra; 208 struct in6_addr saddr6 = ip6->ip6_src; 209 int mcast = 0; 210 union nd_opts ndopts; 211 struct nd_defrouter *dr; 212 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 213 214 /* 215 * We only accept RAs only when 216 * the system-wide variable allows the acceptance, and 217 * per-interface variable allows RAs on the receiving interface. 218 */ 219 if (V_ip6_accept_rtadv == 0) 220 goto freeit; 221 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV)) 222 goto freeit; 223 224 if (ip6->ip6_hlim != 255) { 225 nd6log((LOG_ERR, 226 "nd6_ra_input: invalid hlim (%d) from %s to %s on %s\n", 227 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 228 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 229 goto bad; 230 } 231 232 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 233 nd6log((LOG_ERR, 234 "nd6_ra_input: src %s is not link-local\n", 235 ip6_sprintf(ip6bufs, &saddr6))); 236 goto bad; 237 } 238 239#ifndef PULLDOWN_TEST 240 IP6_EXTHDR_CHECK(m, off, icmp6len,); 241 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off); 242#else 243 IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len); 244 if (nd_ra == NULL) { 245 V_icmp6stat.icp6s_tooshort++; 246 return; 247 } 248#endif 249 250 icmp6len -= sizeof(*nd_ra); 251 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 252 if (nd6_options(&ndopts) < 0) { 253 nd6log((LOG_INFO, 254 "nd6_ra_input: invalid ND option, ignored\n")); 255 /* nd6_options have incremented stats */ 256 goto freeit; 257 } 258 259 { 260 struct nd_defrouter dr0; 261 u_int32_t advreachable = nd_ra->nd_ra_reachable; 262 263 /* remember if this is a multicasted advertisement */ 264 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 265 mcast = 1; 266 267 bzero(&dr0, sizeof(dr0)); 268 dr0.rtaddr = saddr6; 269 dr0.flags = nd_ra->nd_ra_flags_reserved; 270 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 271 dr0.expire = time_second + dr0.rtlifetime; 272 dr0.ifp = ifp; 273 /* unspecified or not? (RFC 2461 6.3.4) */ 274 if (advreachable) { 275 advreachable = ntohl(advreachable); 276 if (advreachable <= MAX_REACHABLE_TIME && 277 ndi->basereachable != advreachable) { 278 ndi->basereachable = advreachable; 279 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 280 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */ 281 } 282 } 283 if (nd_ra->nd_ra_retransmit) 284 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 285 if (nd_ra->nd_ra_curhoplimit) 286 ndi->chlim = nd_ra->nd_ra_curhoplimit; 287 dr = defrtrlist_update(&dr0); 288 } 289 290 /* 291 * prefix 292 */ 293 if (ndopts.nd_opts_pi) { 294 struct nd_opt_hdr *pt; 295 struct nd_opt_prefix_info *pi = NULL; 296 struct nd_prefixctl pr; 297 298 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 299 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 300 pt = (struct nd_opt_hdr *)((caddr_t)pt + 301 (pt->nd_opt_len << 3))) { 302 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 303 continue; 304 pi = (struct nd_opt_prefix_info *)pt; 305 306 if (pi->nd_opt_pi_len != 4) { 307 nd6log((LOG_INFO, 308 "nd6_ra_input: invalid option " 309 "len %d for prefix information option, " 310 "ignored\n", pi->nd_opt_pi_len)); 311 continue; 312 } 313 314 if (128 < pi->nd_opt_pi_prefix_len) { 315 nd6log((LOG_INFO, 316 "nd6_ra_input: invalid prefix " 317 "len %d for prefix information option, " 318 "ignored\n", pi->nd_opt_pi_prefix_len)); 319 continue; 320 } 321 322 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 323 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 324 nd6log((LOG_INFO, 325 "nd6_ra_input: invalid prefix " 326 "%s, ignored\n", 327 ip6_sprintf(ip6bufs, 328 &pi->nd_opt_pi_prefix))); 329 continue; 330 } 331 332 bzero(&pr, sizeof(pr)); 333 pr.ndpr_prefix.sin6_family = AF_INET6; 334 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix); 335 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix; 336 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 337 338 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 339 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 340 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 341 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 342 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 343 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 344 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 345 (void)prelist_update(&pr, dr, m, mcast); 346 } 347 } 348 349 /* 350 * MTU 351 */ 352 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 353 u_long mtu; 354 u_long maxmtu; 355 356 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 357 358 /* lower bound */ 359 if (mtu < IPV6_MMTU) { 360 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option " 361 "mtu=%lu sent from %s, ignoring\n", 362 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src))); 363 goto skip; 364 } 365 366 /* upper bound */ 367 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 368 ? ndi->maxmtu : ifp->if_mtu; 369 if (mtu <= maxmtu) { 370 int change = (ndi->linkmtu != mtu); 371 372 ndi->linkmtu = mtu; 373 if (change) /* in6_maxmtu may change */ 374 in6_setmaxmtu(); 375 } else { 376 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu " 377 "mtu=%lu sent from %s; " 378 "exceeds maxmtu %lu, ignoring\n", 379 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu)); 380 } 381 } 382 383 skip: 384 385 /* 386 * Source link layer address 387 */ 388 { 389 char *lladdr = NULL; 390 int lladdrlen = 0; 391 392 if (ndopts.nd_opts_src_lladdr) { 393 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 394 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 395 } 396 397 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 398 nd6log((LOG_INFO, 399 "nd6_ra_input: lladdrlen mismatch for %s " 400 "(if %d, RA packet %d)\n", ip6_sprintf(ip6bufs, &saddr6), 401 ifp->if_addrlen, lladdrlen - 2)); 402 goto bad; 403 } 404 405 nd6_cache_lladdr(ifp, &saddr6, lladdr, 406 lladdrlen, ND_ROUTER_ADVERT, 0); 407 408 /* 409 * Installing a link-layer address might change the state of the 410 * router's neighbor cache, which might also affect our on-link 411 * detection of adveritsed prefixes. 412 */ 413 pfxlist_onlink_check(); 414 } 415 416 freeit: 417 m_freem(m); 418 return; 419 420 bad: 421 V_icmp6stat.icp6s_badra++; 422 m_freem(m); 423} 424 425/* 426 * default router list proccessing sub routines 427 */ 428 429/* tell the change to user processes watching the routing socket. */ 430static void 431nd6_rtmsg(int cmd, struct rtentry *rt) 432{ 433 struct rt_addrinfo info; 434 435 bzero((caddr_t)&info, sizeof(info)); 436 info.rti_info[RTAX_DST] = rt_key(rt); 437 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 438 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 439 if (rt->rt_ifp) { 440 info.rti_info[RTAX_IFP] = 441 TAILQ_FIRST(&rt->rt_ifp->if_addrlist)->ifa_addr; 442 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr; 443 } 444 445 rt_missmsg(cmd, &info, rt->rt_flags, 0); 446} 447 448void 449defrouter_addreq(struct nd_defrouter *new) 450{ 451 struct sockaddr_in6 def, mask, gate; 452 struct rtentry *newrt = NULL; 453 int s; 454 int error; 455 456 bzero(&def, sizeof(def)); 457 bzero(&mask, sizeof(mask)); 458 bzero(&gate, sizeof(gate)); 459 460 def.sin6_len = mask.sin6_len = gate.sin6_len = 461 sizeof(struct sockaddr_in6); 462 def.sin6_family = gate.sin6_family = AF_INET6; 463 gate.sin6_addr = new->rtaddr; 464 465 s = splnet(); 466 error = rtrequest(RTM_ADD, (struct sockaddr *)&def, 467 (struct sockaddr *)&gate, (struct sockaddr *)&mask, 468 RTF_GATEWAY, &newrt); 469 if (newrt) { 470 RT_LOCK(newrt); 471 nd6_rtmsg(RTM_ADD, newrt); /* tell user process */ 472 RT_REMREF(newrt); 473 RT_UNLOCK(newrt); 474 } 475 if (error == 0) 476 new->installed = 1; 477 splx(s); 478 return; 479} 480 481struct nd_defrouter * 482defrouter_lookup(struct in6_addr *addr, struct ifnet *ifp) 483{ 484 INIT_VNET_INET6(ifp->if_vnet); 485 struct nd_defrouter *dr; 486 487 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 488 dr = TAILQ_NEXT(dr, dr_entry)) { 489 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) 490 return (dr); 491 } 492 493 return (NULL); /* search failed */ 494} 495 496/* 497 * Remove the default route for a given router. 498 * This is just a subroutine function for defrouter_select(), and should 499 * not be called from anywhere else. 500 */ 501static void 502defrouter_delreq(struct nd_defrouter *dr) 503{ 504 struct sockaddr_in6 def, mask, gate; 505 struct rtentry *oldrt = NULL; 506 507 bzero(&def, sizeof(def)); 508 bzero(&mask, sizeof(mask)); 509 bzero(&gate, sizeof(gate)); 510 511 def.sin6_len = mask.sin6_len = gate.sin6_len = 512 sizeof(struct sockaddr_in6); 513 def.sin6_family = gate.sin6_family = AF_INET6; 514 gate.sin6_addr = dr->rtaddr; 515 516 rtrequest(RTM_DELETE, (struct sockaddr *)&def, 517 (struct sockaddr *)&gate, 518 (struct sockaddr *)&mask, RTF_GATEWAY, &oldrt); 519 if (oldrt) { 520 nd6_rtmsg(RTM_DELETE, oldrt); 521 RTFREE(oldrt); 522 } 523 524 dr->installed = 0; 525} 526 527/* 528 * remove all default routes from default router list 529 */ 530void 531defrouter_reset(void) 532{ 533 INIT_VNET_INET6(curvnet); 534 struct nd_defrouter *dr; 535 536 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 537 dr = TAILQ_NEXT(dr, dr_entry)) 538 defrouter_delreq(dr); 539 540 /* 541 * XXX should we also nuke any default routers in the kernel, by 542 * going through them by rtalloc1()? 543 */ 544} 545 546void 547defrtrlist_del(struct nd_defrouter *dr) 548{ 549 INIT_VNET_INET6(curvnet); 550 struct nd_defrouter *deldr = NULL; 551 struct nd_prefix *pr; 552 553 /* 554 * Flush all the routing table entries that use the router 555 * as a next hop. 556 */ 557 if (!V_ip6_forwarding && V_ip6_accept_rtadv) /* XXX: better condition? */ 558 rt6_flush(&dr->rtaddr, dr->ifp); 559 560 if (dr->installed) { 561 deldr = dr; 562 defrouter_delreq(dr); 563 } 564 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 565 566 /* 567 * Also delete all the pointers to the router in each prefix lists. 568 */ 569 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 570 struct nd_pfxrouter *pfxrtr; 571 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 572 pfxrtr_del(pfxrtr); 573 } 574 pfxlist_onlink_check(); 575 576 /* 577 * If the router is the primary one, choose a new one. 578 * Note that defrouter_select() will remove the current gateway 579 * from the routing table. 580 */ 581 if (deldr) 582 defrouter_select(); 583 584 free(dr, M_IP6NDP); 585} 586 587/* 588 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 589 * draft-ietf-ipngwg-router-selection: 590 * 1) Routers that are reachable or probably reachable should be preferred. 591 * If we have more than one (probably) reachable router, prefer ones 592 * with the highest router preference. 593 * 2) When no routers on the list are known to be reachable or 594 * probably reachable, routers SHOULD be selected in a round-robin 595 * fashion, regardless of router preference values. 596 * 3) If the Default Router List is empty, assume that all 597 * destinations are on-link. 598 * 599 * We assume nd_defrouter is sorted by router preference value. 600 * Since the code below covers both with and without router preference cases, 601 * we do not need to classify the cases by ifdef. 602 * 603 * At this moment, we do not try to install more than one default router, 604 * even when the multipath routing is available, because we're not sure about 605 * the benefits for stub hosts comparing to the risk of making the code 606 * complicated and the possibility of introducing bugs. 607 */ 608void 609defrouter_select(void) 610{ 611 INIT_VNET_INET6(curvnet); 612 int s = splnet(); 613 struct nd_defrouter *dr, *selected_dr = NULL, *installed_dr = NULL; 614 struct rtentry *rt = NULL; 615 struct llinfo_nd6 *ln = NULL; 616 617 /* 618 * This function should be called only when acting as an autoconfigured 619 * host. Although the remaining part of this function is not effective 620 * if the node is not an autoconfigured host, we explicitly exclude 621 * such cases here for safety. 622 */ 623 if (V_ip6_forwarding || !V_ip6_accept_rtadv) { 624 nd6log((LOG_WARNING, 625 "defrouter_select: called unexpectedly (forwarding=%d, " 626 "accept_rtadv=%d)\n", V_ip6_forwarding, V_ip6_accept_rtadv)); 627 splx(s); 628 return; 629 } 630 631 /* 632 * Let's handle easy case (3) first: 633 * If default router list is empty, there's nothing to be done. 634 */ 635 if (!TAILQ_FIRST(&V_nd_defrouter)) { 636 splx(s); 637 return; 638 } 639 640 /* 641 * Search for a (probably) reachable router from the list. 642 * We just pick up the first reachable one (if any), assuming that 643 * the ordering rule of the list described in defrtrlist_update(). 644 */ 645 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 646 dr = TAILQ_NEXT(dr, dr_entry)) { 647 if (selected_dr == NULL && 648 (rt = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) && 649 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) && 650 ND6_IS_LLINFO_PROBREACH(ln)) { 651 selected_dr = dr; 652 } 653 654 if (dr->installed && installed_dr == NULL) 655 installed_dr = dr; 656 else if (dr->installed && installed_dr) { 657 /* this should not happen. warn for diagnosis. */ 658 log(LOG_ERR, "defrouter_select: more than one router" 659 " is installed\n"); 660 } 661 } 662 /* 663 * If none of the default routers was found to be reachable, 664 * round-robin the list regardless of preference. 665 * Otherwise, if we have an installed router, check if the selected 666 * (reachable) router should really be preferred to the installed one. 667 * We only prefer the new router when the old one is not reachable 668 * or when the new one has a really higher preference value. 669 */ 670 if (selected_dr == NULL) { 671 if (installed_dr == NULL || !TAILQ_NEXT(installed_dr, dr_entry)) 672 selected_dr = TAILQ_FIRST(&V_nd_defrouter); 673 else 674 selected_dr = TAILQ_NEXT(installed_dr, dr_entry); 675 } else if (installed_dr && 676 (rt = nd6_lookup(&installed_dr->rtaddr, 0, installed_dr->ifp)) && 677 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) && 678 ND6_IS_LLINFO_PROBREACH(ln) && 679 rtpref(selected_dr) <= rtpref(installed_dr)) { 680 selected_dr = installed_dr; 681 } 682 683 /* 684 * If the selected router is different than the installed one, 685 * remove the installed router and install the selected one. 686 * Note that the selected router is never NULL here. 687 */ 688 if (installed_dr != selected_dr) { 689 if (installed_dr) 690 defrouter_delreq(installed_dr); 691 defrouter_addreq(selected_dr); 692 } 693 694 splx(s); 695 return; 696} 697 698/* 699 * for default router selection 700 * regards router-preference field as a 2-bit signed integer 701 */ 702static int 703rtpref(struct nd_defrouter *dr) 704{ 705 switch (dr->flags & ND_RA_FLAG_RTPREF_MASK) { 706 case ND_RA_FLAG_RTPREF_HIGH: 707 return (RTPREF_HIGH); 708 case ND_RA_FLAG_RTPREF_MEDIUM: 709 case ND_RA_FLAG_RTPREF_RSV: 710 return (RTPREF_MEDIUM); 711 case ND_RA_FLAG_RTPREF_LOW: 712 return (RTPREF_LOW); 713 default: 714 /* 715 * This case should never happen. If it did, it would mean a 716 * serious bug of kernel internal. We thus always bark here. 717 * Or, can we even panic? 718 */ 719 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->flags); 720 return (RTPREF_INVALID); 721 } 722 /* NOTREACHED */ 723} 724 725static struct nd_defrouter * 726defrtrlist_update(struct nd_defrouter *new) 727{ 728 INIT_VNET_INET6(curvnet); 729 struct nd_defrouter *dr, *n; 730 int s = splnet(); 731 732 if ((dr = defrouter_lookup(&new->rtaddr, new->ifp)) != NULL) { 733 /* entry exists */ 734 if (new->rtlifetime == 0) { 735 defrtrlist_del(dr); 736 dr = NULL; 737 } else { 738 int oldpref = rtpref(dr); 739 740 /* override */ 741 dr->flags = new->flags; /* xxx flag check */ 742 dr->rtlifetime = new->rtlifetime; 743 dr->expire = new->expire; 744 745 /* 746 * If the preference does not change, there's no need 747 * to sort the entries. 748 */ 749 if (rtpref(new) == oldpref) { 750 splx(s); 751 return (dr); 752 } 753 754 /* 755 * preferred router may be changed, so relocate 756 * this router. 757 * XXX: calling TAILQ_REMOVE directly is a bad manner. 758 * However, since defrtrlist_del() has many side 759 * effects, we intentionally do so here. 760 * defrouter_select() below will handle routing 761 * changes later. 762 */ 763 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 764 n = dr; 765 goto insert; 766 } 767 splx(s); 768 return (dr); 769 } 770 771 /* entry does not exist */ 772 if (new->rtlifetime == 0) { 773 splx(s); 774 return (NULL); 775 } 776 777 n = (struct nd_defrouter *)malloc(sizeof(*n), M_IP6NDP, M_NOWAIT); 778 if (n == NULL) { 779 splx(s); 780 return (NULL); 781 } 782 bzero(n, sizeof(*n)); 783 *n = *new; 784 785insert: 786 /* 787 * Insert the new router in the Default Router List; 788 * The Default Router List should be in the descending order 789 * of router-preferece. Routers with the same preference are 790 * sorted in the arriving time order. 791 */ 792 793 /* insert at the end of the group */ 794 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 795 dr = TAILQ_NEXT(dr, dr_entry)) { 796 if (rtpref(n) > rtpref(dr)) 797 break; 798 } 799 if (dr) 800 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 801 else 802 TAILQ_INSERT_TAIL(&V_nd_defrouter, n, dr_entry); 803 804 defrouter_select(); 805 806 splx(s); 807 808 return (n); 809} 810 811static struct nd_pfxrouter * 812pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 813{ 814 struct nd_pfxrouter *search; 815 816 for (search = pr->ndpr_advrtrs.lh_first; search; search = search->pfr_next) { 817 if (search->router == dr) 818 break; 819 } 820 821 return (search); 822} 823 824static void 825pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 826{ 827 struct nd_pfxrouter *new; 828 829 new = (struct nd_pfxrouter *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT); 830 if (new == NULL) 831 return; 832 bzero(new, sizeof(*new)); 833 new->router = dr; 834 835 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 836 837 pfxlist_onlink_check(); 838} 839 840static void 841pfxrtr_del(struct nd_pfxrouter *pfr) 842{ 843 LIST_REMOVE(pfr, pfr_entry); 844 free(pfr, M_IP6NDP); 845} 846 847struct nd_prefix * 848nd6_prefix_lookup(struct nd_prefixctl *key) 849{ 850 INIT_VNET_INET6(curvnet); 851 struct nd_prefix *search; 852 853 for (search = V_nd_prefix.lh_first; 854 search; search = search->ndpr_next) { 855 if (key->ndpr_ifp == search->ndpr_ifp && 856 key->ndpr_plen == search->ndpr_plen && 857 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 858 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 859 break; 860 } 861 } 862 863 return (search); 864} 865 866int 867nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 868 struct nd_prefix **newp) 869{ 870 INIT_VNET_INET6(curvnet); 871 struct nd_prefix *new = NULL; 872 int error = 0; 873 int i, s; 874 char ip6buf[INET6_ADDRSTRLEN]; 875 876 new = (struct nd_prefix *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT); 877 if (new == NULL) 878 return(ENOMEM); 879 bzero(new, sizeof(*new)); 880 new->ndpr_ifp = pr->ndpr_ifp; 881 new->ndpr_prefix = pr->ndpr_prefix; 882 new->ndpr_plen = pr->ndpr_plen; 883 new->ndpr_vltime = pr->ndpr_vltime; 884 new->ndpr_pltime = pr->ndpr_pltime; 885 new->ndpr_flags = pr->ndpr_flags; 886 if ((error = in6_init_prefix_ltimes(new)) != 0) { 887 free(new, M_IP6NDP); 888 return(error); 889 } 890 new->ndpr_lastupdate = time_second; 891 if (newp != NULL) 892 *newp = new; 893 894 /* initialization */ 895 LIST_INIT(&new->ndpr_advrtrs); 896 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 897 /* make prefix in the canonical form */ 898 for (i = 0; i < 4; i++) 899 new->ndpr_prefix.sin6_addr.s6_addr32[i] &= 900 new->ndpr_mask.s6_addr32[i]; 901 902 s = splnet(); 903 /* link ndpr_entry to nd_prefix list */ 904 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry); 905 splx(s); 906 907 /* ND_OPT_PI_FLAG_ONLINK processing */ 908 if (new->ndpr_raf_onlink) { 909 int e; 910 911 if ((e = nd6_prefix_onlink(new)) != 0) { 912 nd6log((LOG_ERR, "nd6_prelist_add: failed to make " 913 "the prefix %s/%d on-link on %s (errno=%d)\n", 914 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 915 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 916 /* proceed anyway. XXX: is it correct? */ 917 } 918 } 919 920 if (dr) 921 pfxrtr_add(new, dr); 922 923 return 0; 924} 925 926void 927prelist_remove(struct nd_prefix *pr) 928{ 929 INIT_VNET_INET6(curvnet); 930 struct nd_pfxrouter *pfr, *next; 931 int e, s; 932 char ip6buf[INET6_ADDRSTRLEN]; 933 934 /* make sure to invalidate the prefix until it is really freed. */ 935 pr->ndpr_vltime = 0; 936 pr->ndpr_pltime = 0; 937 938 /* 939 * Though these flags are now meaningless, we'd rather keep the value 940 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users 941 * when executing "ndp -p". 942 */ 943 944 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 && 945 (e = nd6_prefix_offlink(pr)) != 0) { 946 nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink " 947 "on %s, errno=%d\n", 948 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 949 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 950 /* what should we do? */ 951 } 952 953 if (pr->ndpr_refcnt > 0) 954 return; /* notice here? */ 955 956 s = splnet(); 957 958 /* unlink ndpr_entry from nd_prefix list */ 959 LIST_REMOVE(pr, ndpr_entry); 960 961 /* free list of routers that adversed the prefix */ 962 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; pfr = next) { 963 next = pfr->pfr_next; 964 965 free(pfr, M_IP6NDP); 966 } 967 splx(s); 968 969 free(pr, M_IP6NDP); 970 971 pfxlist_onlink_check(); 972} 973 974/* 975 * dr - may be NULL 976 */ 977 978static int 979prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr, 980 struct mbuf *m, int mcast) 981{ 982 INIT_VNET_INET6(curvnet); 983 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 984 struct ifaddr *ifa; 985 struct ifnet *ifp = new->ndpr_ifp; 986 struct nd_prefix *pr; 987 int s = splnet(); 988 int error = 0; 989 int newprefix = 0; 990 int auth; 991 struct in6_addrlifetime lt6_tmp; 992 char ip6buf[INET6_ADDRSTRLEN]; 993 994 auth = 0; 995 if (m) { 996 /* 997 * Authenticity for NA consists authentication for 998 * both IP header and IP datagrams, doesn't it ? 999 */ 1000#if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1001 auth = ((m->m_flags & M_AUTHIPHDR) && 1002 (m->m_flags & M_AUTHIPDGM)); 1003#endif 1004 } 1005 1006 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1007 /* 1008 * nd6_prefix_lookup() ensures that pr and new have the same 1009 * prefix on a same interface. 1010 */ 1011 1012 /* 1013 * Update prefix information. Note that the on-link (L) bit 1014 * and the autonomous (A) bit should NOT be changed from 1 1015 * to 0. 1016 */ 1017 if (new->ndpr_raf_onlink == 1) 1018 pr->ndpr_raf_onlink = 1; 1019 if (new->ndpr_raf_auto == 1) 1020 pr->ndpr_raf_auto = 1; 1021 if (new->ndpr_raf_onlink) { 1022 pr->ndpr_vltime = new->ndpr_vltime; 1023 pr->ndpr_pltime = new->ndpr_pltime; 1024 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1025 pr->ndpr_lastupdate = time_second; 1026 } 1027 1028 if (new->ndpr_raf_onlink && 1029 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1030 int e; 1031 1032 if ((e = nd6_prefix_onlink(pr)) != 0) { 1033 nd6log((LOG_ERR, 1034 "prelist_update: failed to make " 1035 "the prefix %s/%d on-link on %s " 1036 "(errno=%d)\n", 1037 ip6_sprintf(ip6buf, 1038 &pr->ndpr_prefix.sin6_addr), 1039 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1040 /* proceed anyway. XXX: is it correct? */ 1041 } 1042 } 1043 1044 if (dr && pfxrtr_lookup(pr, dr) == NULL) 1045 pfxrtr_add(pr, dr); 1046 } else { 1047 struct nd_prefix *newpr = NULL; 1048 1049 newprefix = 1; 1050 1051 if (new->ndpr_vltime == 0) 1052 goto end; 1053 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1054 goto end; 1055 1056 error = nd6_prelist_add(new, dr, &newpr); 1057 if (error != 0 || newpr == NULL) { 1058 nd6log((LOG_NOTICE, "prelist_update: " 1059 "nd6_prelist_add failed for %s/%d on %s " 1060 "errno=%d, returnpr=%p\n", 1061 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr), 1062 new->ndpr_plen, if_name(new->ndpr_ifp), 1063 error, newpr)); 1064 goto end; /* we should just give up in this case. */ 1065 } 1066 1067 /* 1068 * XXX: from the ND point of view, we can ignore a prefix 1069 * with the on-link bit being zero. However, we need a 1070 * prefix structure for references from autoconfigured 1071 * addresses. Thus, we explicitly make sure that the prefix 1072 * itself expires now. 1073 */ 1074 if (newpr->ndpr_raf_onlink == 0) { 1075 newpr->ndpr_vltime = 0; 1076 newpr->ndpr_pltime = 0; 1077 in6_init_prefix_ltimes(newpr); 1078 } 1079 1080 pr = newpr; 1081 } 1082 1083 /* 1084 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1085 * Note that pr must be non NULL at this point. 1086 */ 1087 1088 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1089 if (!new->ndpr_raf_auto) 1090 goto end; 1091 1092 /* 1093 * 5.5.3 (b). the link-local prefix should have been ignored in 1094 * nd6_ra_input. 1095 */ 1096 1097 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1098 if (new->ndpr_pltime > new->ndpr_vltime) { 1099 error = EINVAL; /* XXX: won't be used */ 1100 goto end; 1101 } 1102 1103 /* 1104 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1105 * an address configured by stateless autoconfiguration already in the 1106 * list of addresses associated with the interface, and the Valid 1107 * Lifetime is not 0, form an address. We first check if we have 1108 * a matching prefix. 1109 * Note: we apply a clarification in rfc2462bis-02 here. We only 1110 * consider autoconfigured addresses while RFC2462 simply said 1111 * "address". 1112 */ 1113 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1114 struct in6_ifaddr *ifa6; 1115 u_int32_t remaininglifetime; 1116 1117 if (ifa->ifa_addr->sa_family != AF_INET6) 1118 continue; 1119 1120 ifa6 = (struct in6_ifaddr *)ifa; 1121 1122 /* 1123 * We only consider autoconfigured addresses as per rfc2462bis. 1124 */ 1125 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1126 continue; 1127 1128 /* 1129 * Spec is not clear here, but I believe we should concentrate 1130 * on unicast (i.e. not anycast) addresses. 1131 * XXX: other ia6_flags? detached or duplicated? 1132 */ 1133 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1134 continue; 1135 1136 /* 1137 * Ignore the address if it is not associated with a prefix 1138 * or is associated with a prefix that is different from this 1139 * one. (pr is never NULL here) 1140 */ 1141 if (ifa6->ia6_ndpr != pr) 1142 continue; 1143 1144 if (ia6_match == NULL) /* remember the first one */ 1145 ia6_match = ifa6; 1146 1147 /* 1148 * An already autoconfigured address matched. Now that we 1149 * are sure there is at least one matched address, we can 1150 * proceed to 5.5.3. (e): update the lifetimes according to the 1151 * "two hours" rule and the privacy extension. 1152 * We apply some clarifications in rfc2462bis: 1153 * - use remaininglifetime instead of storedlifetime as a 1154 * variable name 1155 * - remove the dead code in the "two-hour" rule 1156 */ 1157#define TWOHOUR (120*60) 1158 lt6_tmp = ifa6->ia6_lifetime; 1159 1160 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1161 remaininglifetime = ND6_INFINITE_LIFETIME; 1162 else if (time_second - ifa6->ia6_updatetime > 1163 lt6_tmp.ia6t_vltime) { 1164 /* 1165 * The case of "invalid" address. We should usually 1166 * not see this case. 1167 */ 1168 remaininglifetime = 0; 1169 } else 1170 remaininglifetime = lt6_tmp.ia6t_vltime - 1171 (time_second - ifa6->ia6_updatetime); 1172 1173 /* when not updating, keep the current stored lifetime. */ 1174 lt6_tmp.ia6t_vltime = remaininglifetime; 1175 1176 if (TWOHOUR < new->ndpr_vltime || 1177 remaininglifetime < new->ndpr_vltime) { 1178 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1179 } else if (remaininglifetime <= TWOHOUR) { 1180 if (auth) { 1181 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1182 } 1183 } else { 1184 /* 1185 * new->ndpr_vltime <= TWOHOUR && 1186 * TWOHOUR < remaininglifetime 1187 */ 1188 lt6_tmp.ia6t_vltime = TWOHOUR; 1189 } 1190 1191 /* The 2 hour rule is not imposed for preferred lifetime. */ 1192 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1193 1194 in6_init_address_ltimes(pr, <6_tmp); 1195 1196 /* 1197 * We need to treat lifetimes for temporary addresses 1198 * differently, according to 1199 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1200 * we only update the lifetimes when they are in the maximum 1201 * intervals. 1202 */ 1203 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1204 u_int32_t maxvltime, maxpltime; 1205 1206 if (V_ip6_temp_valid_lifetime > 1207 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1208 V_ip6_desync_factor)) { 1209 maxvltime = V_ip6_temp_valid_lifetime - 1210 (time_second - ifa6->ia6_createtime) - 1211 V_ip6_desync_factor; 1212 } else 1213 maxvltime = 0; 1214 if (V_ip6_temp_preferred_lifetime > 1215 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1216 V_ip6_desync_factor)) { 1217 maxpltime = V_ip6_temp_preferred_lifetime - 1218 (time_second - ifa6->ia6_createtime) - 1219 V_ip6_desync_factor; 1220 } else 1221 maxpltime = 0; 1222 1223 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1224 lt6_tmp.ia6t_vltime > maxvltime) { 1225 lt6_tmp.ia6t_vltime = maxvltime; 1226 } 1227 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1228 lt6_tmp.ia6t_pltime > maxpltime) { 1229 lt6_tmp.ia6t_pltime = maxpltime; 1230 } 1231 } 1232 ifa6->ia6_lifetime = lt6_tmp; 1233 ifa6->ia6_updatetime = time_second; 1234 } 1235 if (ia6_match == NULL && new->ndpr_vltime) { 1236 int ifidlen; 1237 1238 /* 1239 * 5.5.3 (d) (continued) 1240 * No address matched and the valid lifetime is non-zero. 1241 * Create a new address. 1242 */ 1243 1244 /* 1245 * Prefix Length check: 1246 * If the sum of the prefix length and interface identifier 1247 * length does not equal 128 bits, the Prefix Information 1248 * option MUST be ignored. The length of the interface 1249 * identifier is defined in a separate link-type specific 1250 * document. 1251 */ 1252 ifidlen = in6_if2idlen(ifp); 1253 if (ifidlen < 0) { 1254 /* this should not happen, so we always log it. */ 1255 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1256 if_name(ifp)); 1257 goto end; 1258 } 1259 if (ifidlen + pr->ndpr_plen != 128) { 1260 nd6log((LOG_INFO, 1261 "prelist_update: invalid prefixlen " 1262 "%d for %s, ignored\n", 1263 pr->ndpr_plen, if_name(ifp))); 1264 goto end; 1265 } 1266 1267 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1268 /* 1269 * note that we should use pr (not new) for reference. 1270 */ 1271 pr->ndpr_refcnt++; 1272 ia6->ia6_ndpr = pr; 1273 1274 /* 1275 * RFC 3041 3.3 (2). 1276 * When a new public address is created as described 1277 * in RFC2462, also create a new temporary address. 1278 * 1279 * RFC 3041 3.5. 1280 * When an interface connects to a new link, a new 1281 * randomized interface identifier should be generated 1282 * immediately together with a new set of temporary 1283 * addresses. Thus, we specifiy 1 as the 2nd arg of 1284 * in6_tmpifadd(). 1285 */ 1286 if (V_ip6_use_tempaddr) { 1287 int e; 1288 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1289 nd6log((LOG_NOTICE, "prelist_update: " 1290 "failed to create a temporary " 1291 "address, errno=%d\n", 1292 e)); 1293 } 1294 } 1295 1296 /* 1297 * A newly added address might affect the status 1298 * of other addresses, so we check and update it. 1299 * XXX: what if address duplication happens? 1300 */ 1301 pfxlist_onlink_check(); 1302 } else { 1303 /* just set an error. do not bark here. */ 1304 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1305 } 1306 } 1307 1308 end: 1309 splx(s); 1310 return error; 1311} 1312 1313/* 1314 * A supplement function used in the on-link detection below; 1315 * detect if a given prefix has a (probably) reachable advertising router. 1316 * XXX: lengthy function name... 1317 */ 1318static struct nd_pfxrouter * 1319find_pfxlist_reachable_router(struct nd_prefix *pr) 1320{ 1321 struct nd_pfxrouter *pfxrtr; 1322 struct rtentry *rt; 1323 struct llinfo_nd6 *ln; 1324 1325 for (pfxrtr = LIST_FIRST(&pr->ndpr_advrtrs); pfxrtr; 1326 pfxrtr = LIST_NEXT(pfxrtr, pfr_entry)) { 1327 if ((rt = nd6_lookup(&pfxrtr->router->rtaddr, 0, 1328 pfxrtr->router->ifp)) && 1329 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) && 1330 ND6_IS_LLINFO_PROBREACH(ln)) 1331 break; /* found */ 1332 } 1333 1334 return (pfxrtr); 1335} 1336 1337/* 1338 * Check if each prefix in the prefix list has at least one available router 1339 * that advertised the prefix (a router is "available" if its neighbor cache 1340 * entry is reachable or probably reachable). 1341 * If the check fails, the prefix may be off-link, because, for example, 1342 * we have moved from the network but the lifetime of the prefix has not 1343 * expired yet. So we should not use the prefix if there is another prefix 1344 * that has an available router. 1345 * But, if there is no prefix that has an available router, we still regards 1346 * all the prefixes as on-link. This is because we can't tell if all the 1347 * routers are simply dead or if we really moved from the network and there 1348 * is no router around us. 1349 */ 1350void 1351pfxlist_onlink_check() 1352{ 1353 INIT_VNET_INET6(curvnet); 1354 struct nd_prefix *pr; 1355 struct in6_ifaddr *ifa; 1356 struct nd_defrouter *dr; 1357 struct nd_pfxrouter *pfxrtr = NULL; 1358 1359 /* 1360 * Check if there is a prefix that has a reachable advertising 1361 * router. 1362 */ 1363 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1364 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1365 break; 1366 } 1367 1368 /* 1369 * If we have no such prefix, check whether we still have a router 1370 * that does not advertise any prefixes. 1371 */ 1372 if (pr == NULL) { 1373 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 1374 dr = TAILQ_NEXT(dr, dr_entry)) { 1375 struct nd_prefix *pr0; 1376 1377 for (pr0 = V_nd_prefix.lh_first; pr0; 1378 pr0 = pr0->ndpr_next) { 1379 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1380 break; 1381 } 1382 if (pfxrtr != NULL) 1383 break; 1384 } 1385 } 1386 if (pr != NULL || (TAILQ_FIRST(&V_nd_defrouter) && pfxrtr == NULL)) { 1387 /* 1388 * There is at least one prefix that has a reachable router, 1389 * or at least a router which probably does not advertise 1390 * any prefixes. The latter would be the case when we move 1391 * to a new link where we have a router that does not provide 1392 * prefixes and we configure an address by hand. 1393 * Detach prefixes which have no reachable advertising 1394 * router, and attach other prefixes. 1395 */ 1396 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1397 /* XXX: a link-local prefix should never be detached */ 1398 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1399 continue; 1400 1401 /* 1402 * we aren't interested in prefixes without the L bit 1403 * set. 1404 */ 1405 if (pr->ndpr_raf_onlink == 0) 1406 continue; 1407 1408 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1409 find_pfxlist_reachable_router(pr) == NULL) 1410 pr->ndpr_stateflags |= NDPRF_DETACHED; 1411 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1412 find_pfxlist_reachable_router(pr) != 0) 1413 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1414 } 1415 } else { 1416 /* there is no prefix that has a reachable router */ 1417 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1418 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1419 continue; 1420 1421 if (pr->ndpr_raf_onlink == 0) 1422 continue; 1423 1424 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1425 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1426 } 1427 } 1428 1429 /* 1430 * Remove each interface route associated with a (just) detached 1431 * prefix, and reinstall the interface route for a (just) attached 1432 * prefix. Note that all attempt of reinstallation does not 1433 * necessarily success, when a same prefix is shared among multiple 1434 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1435 * so we don't have to care about them. 1436 */ 1437 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1438 int e; 1439 char ip6buf[INET6_ADDRSTRLEN]; 1440 1441 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1442 continue; 1443 1444 if (pr->ndpr_raf_onlink == 0) 1445 continue; 1446 1447 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1448 (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1449 if ((e = nd6_prefix_offlink(pr)) != 0) { 1450 nd6log((LOG_ERR, 1451 "pfxlist_onlink_check: failed to " 1452 "make %s/%d offlink, errno=%d\n", 1453 ip6_sprintf(ip6buf, 1454 &pr->ndpr_prefix.sin6_addr), 1455 pr->ndpr_plen, e)); 1456 } 1457 } 1458 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1459 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 && 1460 pr->ndpr_raf_onlink) { 1461 if ((e = nd6_prefix_onlink(pr)) != 0) { 1462 nd6log((LOG_ERR, 1463 "pfxlist_onlink_check: failed to " 1464 "make %s/%d onlink, errno=%d\n", 1465 ip6_sprintf(ip6buf, 1466 &pr->ndpr_prefix.sin6_addr), 1467 pr->ndpr_plen, e)); 1468 } 1469 } 1470 } 1471 1472 /* 1473 * Changes on the prefix status might affect address status as well. 1474 * Make sure that all addresses derived from an attached prefix are 1475 * attached, and that all addresses derived from a detached prefix are 1476 * detached. Note, however, that a manually configured address should 1477 * always be attached. 1478 * The precise detection logic is same as the one for prefixes. 1479 */ 1480 for (ifa = V_in6_ifaddr; ifa; ifa = ifa->ia_next) { 1481 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1482 continue; 1483 1484 if (ifa->ia6_ndpr == NULL) { 1485 /* 1486 * This can happen when we first configure the address 1487 * (i.e. the address exists, but the prefix does not). 1488 * XXX: complicated relationships... 1489 */ 1490 continue; 1491 } 1492 1493 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1494 break; 1495 } 1496 if (ifa) { 1497 for (ifa = V_in6_ifaddr; ifa; ifa = ifa->ia_next) { 1498 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1499 continue; 1500 1501 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1502 continue; 1503 1504 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 1505 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1506 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1507 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1508 nd6_dad_start((struct ifaddr *)ifa, 0); 1509 } 1510 } else { 1511 ifa->ia6_flags |= IN6_IFF_DETACHED; 1512 } 1513 } 1514 } 1515 else { 1516 for (ifa = V_in6_ifaddr; ifa; ifa = ifa->ia_next) { 1517 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1518 continue; 1519 1520 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1521 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1522 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1523 /* Do we need a delay in this case? */ 1524 nd6_dad_start((struct ifaddr *)ifa, 0); 1525 } 1526 } 1527 } 1528} 1529 1530int 1531nd6_prefix_onlink(struct nd_prefix *pr) 1532{ 1533 INIT_VNET_INET6(curvnet); 1534 struct ifaddr *ifa; 1535 struct ifnet *ifp = pr->ndpr_ifp; 1536 struct sockaddr_in6 mask6; 1537 struct nd_prefix *opr; 1538 u_long rtflags; 1539 int error = 0; 1540 struct rtentry *rt = NULL; 1541 char ip6buf[INET6_ADDRSTRLEN]; 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(ip6buf, &pr->ndpr_prefix.sin6_addr), 1548 pr->ndpr_plen)); 1549 return (EEXIST); 1550 } 1551 1552 /* 1553 * Add the interface route associated with the prefix. Before 1554 * installing the route, check if there's the same prefix on another 1555 * interface, and the prefix has already installed the interface route. 1556 * Although such a configuration is expected to be rare, we explicitly 1557 * allow it. 1558 */ 1559 for (opr = V_nd_prefix.lh_first; opr; opr = opr->ndpr_next) { 1560 if (opr == pr) 1561 continue; 1562 1563 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 1564 continue; 1565 1566 if (opr->ndpr_plen == pr->ndpr_plen && 1567 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1568 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) 1569 return (0); 1570 } 1571 1572 /* 1573 * We prefer link-local addresses as the associated interface address. 1574 */ 1575 /* search for a link-local addr */ 1576 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 1577 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 1578 if (ifa == NULL) { 1579 /* XXX: freebsd does not have ifa_ifwithaf */ 1580 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1581 if (ifa->ifa_addr->sa_family == AF_INET6) 1582 break; 1583 } 1584 /* should we care about ia6_flags? */ 1585 } 1586 if (ifa == NULL) { 1587 /* 1588 * This can still happen, when, for example, we receive an RA 1589 * containing a prefix with the L bit set and the A bit clear, 1590 * after removing all IPv6 addresses on the receiving 1591 * interface. This should, of course, be rare though. 1592 */ 1593 nd6log((LOG_NOTICE, 1594 "nd6_prefix_onlink: failed to find any ifaddr" 1595 " to add route for a prefix(%s/%d) on %s\n", 1596 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1597 pr->ndpr_plen, if_name(ifp))); 1598 return (0); 1599 } 1600 1601 /* 1602 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs. 1603 * ifa->ifa_rtrequest = nd6_rtrequest; 1604 */ 1605 bzero(&mask6, sizeof(mask6)); 1606 mask6.sin6_len = sizeof(mask6); 1607 mask6.sin6_addr = pr->ndpr_mask; 1608 rtflags = ifa->ifa_flags | RTF_CLONING | RTF_UP; 1609 if (nd6_need_cache(ifp)) { 1610 /* explicitly set in case ifa_flags does not set the flag. */ 1611 rtflags |= RTF_CLONING; 1612 } else { 1613 /* 1614 * explicitly clear the cloning bit in case ifa_flags sets it. 1615 */ 1616 rtflags &= ~RTF_CLONING; 1617 } 1618 error = rtrequest(RTM_ADD, (struct sockaddr *)&pr->ndpr_prefix, 1619 ifa->ifa_addr, (struct sockaddr *)&mask6, rtflags, &rt); 1620 if (error == 0) { 1621 if (rt != NULL) /* this should be non NULL, though */ 1622 nd6_rtmsg(RTM_ADD, rt); 1623 pr->ndpr_stateflags |= NDPRF_ONLINK; 1624 } else { 1625 char ip6bufg[INET6_ADDRSTRLEN], ip6bufm[INET6_ADDRSTRLEN]; 1626 nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add route for a" 1627 " prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx " 1628 "errno = %d\n", 1629 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1630 pr->ndpr_plen, if_name(ifp), 1631 ip6_sprintf(ip6bufg, &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr), 1632 ip6_sprintf(ip6bufm, &mask6.sin6_addr), rtflags, error)); 1633 } 1634 1635 if (rt != NULL) { 1636 RT_LOCK(rt); 1637 RT_REMREF(rt); 1638 RT_UNLOCK(rt); 1639 } 1640 1641 return (error); 1642} 1643 1644int 1645nd6_prefix_offlink(struct nd_prefix *pr) 1646{ 1647 INIT_VNET_INET6(curvnet); 1648 int error = 0; 1649 struct ifnet *ifp = pr->ndpr_ifp; 1650 struct nd_prefix *opr; 1651 struct sockaddr_in6 sa6, mask6; 1652 struct rtentry *rt = NULL; 1653 char ip6buf[INET6_ADDRSTRLEN]; 1654 1655 /* sanity check */ 1656 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1657 nd6log((LOG_ERR, 1658 "nd6_prefix_offlink: %s/%d is already off-link\n", 1659 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1660 pr->ndpr_plen)); 1661 return (EEXIST); 1662 } 1663 1664 bzero(&sa6, sizeof(sa6)); 1665 sa6.sin6_family = AF_INET6; 1666 sa6.sin6_len = sizeof(sa6); 1667 bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr, 1668 sizeof(struct in6_addr)); 1669 bzero(&mask6, sizeof(mask6)); 1670 mask6.sin6_family = AF_INET6; 1671 mask6.sin6_len = sizeof(sa6); 1672 bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr)); 1673 error = rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL, 1674 (struct sockaddr *)&mask6, 0, &rt); 1675 if (error == 0) { 1676 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 1677 1678 /* report the route deletion to the routing socket. */ 1679 if (rt != NULL) 1680 nd6_rtmsg(RTM_DELETE, rt); 1681 1682 /* 1683 * There might be the same prefix on another interface, 1684 * the prefix which could not be on-link just because we have 1685 * the interface route (see comments in nd6_prefix_onlink). 1686 * If there's one, try to make the prefix on-link on the 1687 * interface. 1688 */ 1689 for (opr = V_nd_prefix.lh_first; opr; opr = opr->ndpr_next) { 1690 if (opr == pr) 1691 continue; 1692 1693 if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0) 1694 continue; 1695 1696 /* 1697 * KAME specific: detached prefixes should not be 1698 * on-link. 1699 */ 1700 if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1701 continue; 1702 1703 if (opr->ndpr_plen == pr->ndpr_plen && 1704 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1705 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 1706 int e; 1707 1708 if ((e = nd6_prefix_onlink(opr)) != 0) { 1709 nd6log((LOG_ERR, 1710 "nd6_prefix_offlink: failed to " 1711 "recover a prefix %s/%d from %s " 1712 "to %s (errno = %d)\n", 1713 ip6_sprintf(ip6buf, 1714 &opr->ndpr_prefix.sin6_addr), 1715 opr->ndpr_plen, if_name(ifp), 1716 if_name(opr->ndpr_ifp), e)); 1717 } 1718 } 1719 } 1720 } else { 1721 /* XXX: can we still set the NDPRF_ONLINK flag? */ 1722 nd6log((LOG_ERR, 1723 "nd6_prefix_offlink: failed to delete route: " 1724 "%s/%d on %s (errno = %d)\n", 1725 ip6_sprintf(ip6buf, &sa6.sin6_addr), pr->ndpr_plen, 1726 if_name(ifp), error)); 1727 } 1728 1729 if (rt != NULL) { 1730 RTFREE(rt); 1731 } 1732 1733 return (error); 1734} 1735 1736static struct in6_ifaddr * 1737in6_ifadd(struct nd_prefixctl *pr, int mcast) 1738{ 1739 INIT_VNET_INET6(curvnet); 1740 struct ifnet *ifp = pr->ndpr_ifp; 1741 struct ifaddr *ifa; 1742 struct in6_aliasreq ifra; 1743 struct in6_ifaddr *ia, *ib; 1744 int error, plen0; 1745 struct in6_addr mask; 1746 int prefixlen = pr->ndpr_plen; 1747 int updateflags; 1748 char ip6buf[INET6_ADDRSTRLEN]; 1749 1750 in6_prefixlen2mask(&mask, prefixlen); 1751 1752 /* 1753 * find a link-local address (will be interface ID). 1754 * Is it really mandatory? Theoretically, a global or a site-local 1755 * address can be configured without a link-local address, if we 1756 * have a unique interface identifier... 1757 * 1758 * it is not mandatory to have a link-local address, we can generate 1759 * interface identifier on the fly. we do this because: 1760 * (1) it should be the easiest way to find interface identifier. 1761 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1762 * for multiple addresses on a single interface, and possible shortcut 1763 * of DAD. we omitted DAD for this reason in the past. 1764 * (3) a user can prevent autoconfiguration of global address 1765 * by removing link-local address by hand (this is partly because we 1766 * don't have other way to control the use of IPv6 on an interface. 1767 * this has been our design choice - cf. NRL's "ifconfig auto"). 1768 * (4) it is easier to manage when an interface has addresses 1769 * with the same interface identifier, than to have multiple addresses 1770 * with different interface identifiers. 1771 */ 1772 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1773 if (ifa) 1774 ib = (struct in6_ifaddr *)ifa; 1775 else 1776 return NULL; 1777 1778 /* prefixlen + ifidlen must be equal to 128 */ 1779 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1780 if (prefixlen != plen0) { 1781 nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s " 1782 "(prefix=%d ifid=%d)\n", 1783 if_name(ifp), prefixlen, 128 - plen0)); 1784 return NULL; 1785 } 1786 1787 /* make ifaddr */ 1788 1789 bzero(&ifra, sizeof(ifra)); 1790 /* 1791 * in6_update_ifa() does not use ifra_name, but we accurately set it 1792 * for safety. 1793 */ 1794 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1795 ifra.ifra_addr.sin6_family = AF_INET6; 1796 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 1797 /* prefix */ 1798 ifra.ifra_addr.sin6_addr = pr->ndpr_prefix.sin6_addr; 1799 ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0]; 1800 ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1]; 1801 ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2]; 1802 ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3]; 1803 1804 /* interface ID */ 1805 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1806 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1807 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1808 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1809 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1810 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1811 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1812 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1813 1814 /* new prefix mask. */ 1815 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); 1816 ifra.ifra_prefixmask.sin6_family = AF_INET6; 1817 bcopy(&mask, &ifra.ifra_prefixmask.sin6_addr, 1818 sizeof(ifra.ifra_prefixmask.sin6_addr)); 1819 1820 /* lifetimes. */ 1821 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1822 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1823 1824 /* XXX: scope zone ID? */ 1825 1826 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1827 1828 /* 1829 * Make sure that we do not have this address already. This should 1830 * usually not happen, but we can still see this case, e.g., if we 1831 * have manually configured the exact address to be configured. 1832 */ 1833 if (in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr) != NULL) { 1834 /* this should be rare enough to make an explicit log */ 1835 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1836 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr)); 1837 return (NULL); 1838 } 1839 1840 /* 1841 * Allocate ifaddr structure, link into chain, etc. 1842 * If we are going to create a new address upon receiving a multicasted 1843 * RA, we need to impose a random delay before starting DAD. 1844 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1845 */ 1846 updateflags = 0; 1847 if (mcast) 1848 updateflags |= IN6_IFAUPDATE_DADDELAY; 1849 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 1850 nd6log((LOG_ERR, 1851 "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n", 1852 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr), 1853 if_name(ifp), error)); 1854 return (NULL); /* ifaddr must not have been allocated. */ 1855 } 1856 1857 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1858 1859 return (ia); /* this is always non-NULL */ 1860} 1861 1862/* 1863 * ia0 - corresponding public address 1864 */ 1865int 1866in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay) 1867{ 1868 INIT_VNET_INET6(curvnet); 1869 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 1870 struct in6_ifaddr *newia, *ia; 1871 struct in6_aliasreq ifra; 1872 int i, error; 1873 int trylimit = 3; /* XXX: adhoc value */ 1874 int updateflags; 1875 u_int32_t randid[2]; 1876 time_t vltime0, pltime0; 1877 1878 bzero(&ifra, sizeof(ifra)); 1879 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1880 ifra.ifra_addr = ia0->ia_addr; 1881 /* copy prefix mask */ 1882 ifra.ifra_prefixmask = ia0->ia_prefixmask; 1883 /* clear the old IFID */ 1884 for (i = 0; i < 4; i++) { 1885 ifra.ifra_addr.sin6_addr.s6_addr32[i] &= 1886 ifra.ifra_prefixmask.sin6_addr.s6_addr32[i]; 1887 } 1888 1889 again: 1890 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 1891 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 1892 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good " 1893 "random IFID\n")); 1894 return (EINVAL); 1895 } 1896 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1897 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 1898 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1899 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 1900 1901 /* 1902 * in6_get_tmpifid() quite likely provided a unique interface ID. 1903 * However, we may still have a chance to see collision, because 1904 * there may be a time lag between generation of the ID and generation 1905 * of the address. So, we'll do one more sanity check. 1906 */ 1907 for (ia = V_in6_ifaddr; ia; ia = ia->ia_next) { 1908 if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, 1909 &ifra.ifra_addr.sin6_addr)) { 1910 if (trylimit-- == 0) { 1911 /* 1912 * Give up. Something strange should have 1913 * happened. 1914 */ 1915 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to " 1916 "find a unique random IFID\n")); 1917 return (EEXIST); 1918 } 1919 forcegen = 1; 1920 goto again; 1921 } 1922 } 1923 1924 /* 1925 * The Valid Lifetime is the lower of the Valid Lifetime of the 1926 * public address or TEMP_VALID_LIFETIME. 1927 * The Preferred Lifetime is the lower of the Preferred Lifetime 1928 * of the public address or TEMP_PREFERRED_LIFETIME - 1929 * DESYNC_FACTOR. 1930 */ 1931 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 1932 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 1933 (ia0->ia6_lifetime.ia6t_vltime - 1934 (time_second - ia0->ia6_updatetime)); 1935 if (vltime0 > V_ip6_temp_valid_lifetime) 1936 vltime0 = V_ip6_temp_valid_lifetime; 1937 } else 1938 vltime0 = V_ip6_temp_valid_lifetime; 1939 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 1940 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 1941 (ia0->ia6_lifetime.ia6t_pltime - 1942 (time_second - ia0->ia6_updatetime)); 1943 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){ 1944 pltime0 = V_ip6_temp_preferred_lifetime - 1945 V_ip6_desync_factor; 1946 } 1947 } else 1948 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor; 1949 ifra.ifra_lifetime.ia6t_vltime = vltime0; 1950 ifra.ifra_lifetime.ia6t_pltime = pltime0; 1951 1952 /* 1953 * A temporary address is created only if this calculated Preferred 1954 * Lifetime is greater than REGEN_ADVANCE time units. 1955 */ 1956 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance) 1957 return (0); 1958 1959 /* XXX: scope zone ID? */ 1960 1961 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 1962 1963 /* allocate ifaddr structure, link into chain, etc. */ 1964 updateflags = 0; 1965 if (delay) 1966 updateflags |= IN6_IFAUPDATE_DADDELAY; 1967 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 1968 return (error); 1969 1970 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1971 if (newia == NULL) { /* XXX: can it happen? */ 1972 nd6log((LOG_ERR, 1973 "in6_tmpifadd: ifa update succeeded, but we got " 1974 "no ifaddr\n")); 1975 return (EINVAL); /* XXX */ 1976 } 1977 newia->ia6_ndpr = ia0->ia6_ndpr; 1978 newia->ia6_ndpr->ndpr_refcnt++; 1979 1980 /* 1981 * A newly added address might affect the status of other addresses. 1982 * XXX: when the temporary address is generated with a new public 1983 * address, the onlink check is redundant. However, it would be safe 1984 * to do the check explicitly everywhere a new address is generated, 1985 * and, in fact, we surely need the check when we create a new 1986 * temporary address due to deprecation of an old temporary address. 1987 */ 1988 pfxlist_onlink_check(); 1989 1990 return (0); 1991} 1992 1993static int 1994in6_init_prefix_ltimes(struct nd_prefix *ndpr) 1995{ 1996 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 1997 ndpr->ndpr_preferred = 0; 1998 else 1999 ndpr->ndpr_preferred = time_second + ndpr->ndpr_pltime; 2000 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2001 ndpr->ndpr_expire = 0; 2002 else 2003 ndpr->ndpr_expire = time_second + ndpr->ndpr_vltime; 2004 2005 return 0; 2006} 2007 2008static void 2009in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6) 2010{ 2011 /* init ia6t_expire */ 2012 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 2013 lt6->ia6t_expire = 0; 2014 else { 2015 lt6->ia6t_expire = time_second; 2016 lt6->ia6t_expire += lt6->ia6t_vltime; 2017 } 2018 2019 /* init ia6t_preferred */ 2020 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 2021 lt6->ia6t_preferred = 0; 2022 else { 2023 lt6->ia6t_preferred = time_second; 2024 lt6->ia6t_preferred += lt6->ia6t_pltime; 2025 } 2026} 2027 2028/* 2029 * Delete all the routing table entries that use the specified gateway. 2030 * XXX: this function causes search through all entries of routing table, so 2031 * it shouldn't be called when acting as a router. 2032 */ 2033void 2034rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2035{ 2036 INIT_VNET_NET(curvnet); 2037 struct radix_node_head *rnh = V_rt_tables[0][AF_INET6]; 2038 int s = splnet(); 2039 2040 /* We'll care only link-local addresses */ 2041 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) { 2042 splx(s); 2043 return; 2044 } 2045 2046 RADIX_NODE_HEAD_LOCK(rnh); 2047 rnh->rnh_walktree(rnh, rt6_deleteroute, (void *)gateway); 2048 RADIX_NODE_HEAD_UNLOCK(rnh); 2049 splx(s); 2050} 2051 2052static int 2053rt6_deleteroute(struct radix_node *rn, void *arg) 2054{ 2055#define SIN6(s) ((struct sockaddr_in6 *)s) 2056 struct rtentry *rt = (struct rtentry *)rn; 2057 struct in6_addr *gate = (struct in6_addr *)arg; 2058 2059 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6) 2060 return (0); 2061 2062 if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) { 2063 return (0); 2064 } 2065 2066 /* 2067 * Do not delete a static route. 2068 * XXX: this seems to be a bit ad-hoc. Should we consider the 2069 * 'cloned' bit instead? 2070 */ 2071 if ((rt->rt_flags & RTF_STATIC) != 0) 2072 return (0); 2073 2074 /* 2075 * We delete only host route. This means, in particular, we don't 2076 * delete default route. 2077 */ 2078 if ((rt->rt_flags & RTF_HOST) == 0) 2079 return (0); 2080 2081 return (rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, 2082 rt_mask(rt), rt->rt_flags, 0)); 2083#undef SIN6 2084} 2085 2086int 2087nd6_setdefaultiface(int ifindex) 2088{ 2089 INIT_VNET_NET(curvnet); 2090 INIT_VNET_INET6(curvnet); 2091 int error = 0; 2092 2093 if (ifindex < 0 || V_if_index < ifindex) 2094 return (EINVAL); 2095 if (ifindex != 0 && !ifnet_byindex(ifindex)) 2096 return (EINVAL); 2097 2098 if (V_nd6_defifindex != ifindex) { 2099 V_nd6_defifindex = ifindex; 2100 if (V_nd6_defifindex > 0) 2101 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex); 2102 else 2103 V_nd6_defifp = NULL; 2104 2105 /* 2106 * Our current implementation assumes one-to-one maping between 2107 * interfaces and links, so it would be natural to use the 2108 * default interface as the default link. 2109 */ 2110 scope6_setdefault(V_nd6_defifp); 2111 } 2112 2113 return (error); 2114} 2115