nd6_rtr.c revision 194907
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 194907 2009-06-24 21:00:25Z rwatson $"); 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/lock.h> 47#include <sys/errno.h> 48#include <sys/rwlock.h> 49#include <sys/syslog.h> 50#include <sys/queue.h> 51#include <sys/vimage.h> 52 53#include <net/if.h> 54#include <net/if_types.h> 55#include <net/if_dl.h> 56#include <net/route.h> 57#include <net/radix.h> 58#include <net/vnet.h> 59 60#include <netinet/in.h> 61#include <net/if_llatbl.h> 62#include <netinet6/in6_var.h> 63#include <netinet6/in6_ifattach.h> 64#include <netinet/ip6.h> 65#include <netinet6/ip6_var.h> 66#include <netinet6/nd6.h> 67#include <netinet/icmp6.h> 68#include <netinet6/scope6_var.h> 69#include <netinet6/vinet6.h> 70 71static int rtpref(struct nd_defrouter *); 72static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 73static int prelist_update __P((struct nd_prefixctl *, struct nd_defrouter *, 74 struct mbuf *, int)); 75static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int); 76static struct nd_pfxrouter *pfxrtr_lookup __P((struct nd_prefix *, 77 struct nd_defrouter *)); 78static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *); 79static void pfxrtr_del(struct nd_pfxrouter *); 80static struct nd_pfxrouter *find_pfxlist_reachable_router 81(struct nd_prefix *); 82static void defrouter_delreq(struct nd_defrouter *); 83static void nd6_rtmsg(int, struct rtentry *); 84 85static int in6_init_prefix_ltimes(struct nd_prefix *); 86static void in6_init_address_ltimes __P((struct nd_prefix *, 87 struct in6_addrlifetime *)); 88 89static int rt6_deleteroute(struct radix_node *, void *); 90 91#ifdef VIMAGE_GLOBALS 92extern int nd6_recalc_reachtm_interval; 93 94static struct ifnet *nd6_defifp; 95int nd6_defifindex; 96 97int ip6_use_tempaddr; 98int ip6_desync_factor; 99u_int32_t ip6_temp_preferred_lifetime; 100u_int32_t ip6_temp_valid_lifetime; 101int ip6_temp_regen_advance; 102#endif 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 */ 118void 119nd6_rs_input(struct mbuf *m, int off, int icmp6len) 120{ 121 INIT_VNET_INET6(curvnet); 122 struct ifnet *ifp = m->m_pkthdr.rcvif; 123 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 124 struct nd_router_solicit *nd_rs; 125 struct in6_addr saddr6 = ip6->ip6_src; 126 char *lladdr = NULL; 127 int lladdrlen = 0; 128 union nd_opts ndopts; 129 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 130 131 /* If I'm not a router, ignore it. */ 132 if (V_ip6_accept_rtadv != 0 || V_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(ip6bufs, &ip6->ip6_src), 140 ip6_sprintf(ip6bufd, &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_INC(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(ip6bufs, &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_INC(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 */ 203void 204nd6_ra_input(struct mbuf *m, int off, int icmp6len) 205{ 206 INIT_VNET_INET6(curvnet); 207 struct ifnet *ifp = m->m_pkthdr.rcvif; 208 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 209 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 210 struct nd_router_advert *nd_ra; 211 struct in6_addr saddr6 = ip6->ip6_src; 212 int mcast = 0; 213 union nd_opts ndopts; 214 struct nd_defrouter *dr; 215 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 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 (V_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(ip6bufs, &ip6->ip6_src), 231 ip6_sprintf(ip6bufd, &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(ip6bufs, &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_INC(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 = V_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(ip6bufs, 331 &pi->nd_opt_pi_prefix))); 332 continue; 333 } 334 335 bzero(&pr, sizeof(pr)); 336 pr.ndpr_prefix.sin6_family = AF_INET6; 337 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix); 338 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix; 339 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 340 341 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 342 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 343 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 344 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 345 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 346 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 347 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 348 (void)prelist_update(&pr, dr, m, mcast); 349 } 350 } 351 352 /* 353 * MTU 354 */ 355 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 356 u_long mtu; 357 u_long maxmtu; 358 359 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 360 361 /* lower bound */ 362 if (mtu < IPV6_MMTU) { 363 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option " 364 "mtu=%lu sent from %s, ignoring\n", 365 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src))); 366 goto skip; 367 } 368 369 /* upper bound */ 370 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 371 ? ndi->maxmtu : ifp->if_mtu; 372 if (mtu <= maxmtu) { 373 int change = (ndi->linkmtu != mtu); 374 375 ndi->linkmtu = mtu; 376 if (change) /* in6_maxmtu may change */ 377 in6_setmaxmtu(); 378 } else { 379 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu " 380 "mtu=%lu sent from %s; " 381 "exceeds maxmtu %lu, ignoring\n", 382 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu)); 383 } 384 } 385 386 skip: 387 388 /* 389 * Source link layer address 390 */ 391 { 392 char *lladdr = NULL; 393 int lladdrlen = 0; 394 395 if (ndopts.nd_opts_src_lladdr) { 396 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 397 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 398 } 399 400 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 401 nd6log((LOG_INFO, 402 "nd6_ra_input: lladdrlen mismatch for %s " 403 "(if %d, RA packet %d)\n", ip6_sprintf(ip6bufs, &saddr6), 404 ifp->if_addrlen, lladdrlen - 2)); 405 goto bad; 406 } 407 408 nd6_cache_lladdr(ifp, &saddr6, lladdr, 409 lladdrlen, ND_ROUTER_ADVERT, 0); 410 411 /* 412 * Installing a link-layer address might change the state of the 413 * router's neighbor cache, which might also affect our on-link 414 * detection of adveritsed prefixes. 415 */ 416 pfxlist_onlink_check(); 417 } 418 419 freeit: 420 m_freem(m); 421 return; 422 423 bad: 424 ICMP6STAT_INC(icp6s_badra); 425 m_freem(m); 426} 427 428/* 429 * default router list proccessing sub routines 430 */ 431 432/* tell the change to user processes watching the routing socket. */ 433static void 434nd6_rtmsg(int cmd, struct rtentry *rt) 435{ 436 struct rt_addrinfo info; 437 struct ifnet *ifp; 438 struct ifaddr *ifa; 439 440 bzero((caddr_t)&info, sizeof(info)); 441 info.rti_info[RTAX_DST] = rt_key(rt); 442 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 443 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 444 ifp = rt->rt_ifp; 445 if (ifp != NULL) { 446 IF_ADDR_LOCK(ifp); 447 ifa = TAILQ_FIRST(&ifp->if_addrhead); 448 info.rti_info[RTAX_IFP] = ifa->ifa_addr; 449 ifa_ref(ifa); 450 IF_ADDR_UNLOCK(ifp); 451 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr; 452 } else 453 ifa = NULL; 454 455 rt_missmsg(cmd, &info, rt->rt_flags, 0); 456 if (ifa != NULL) 457 ifa_free(ifa); 458} 459 460void 461defrouter_addreq(struct nd_defrouter *new) 462{ 463 struct sockaddr_in6 def, mask, gate; 464 struct rtentry *newrt = NULL; 465 int s; 466 int error; 467 468 bzero(&def, sizeof(def)); 469 bzero(&mask, sizeof(mask)); 470 bzero(&gate, sizeof(gate)); 471 472 def.sin6_len = mask.sin6_len = gate.sin6_len = 473 sizeof(struct sockaddr_in6); 474 def.sin6_family = gate.sin6_family = AF_INET6; 475 gate.sin6_addr = new->rtaddr; 476 477 s = splnet(); 478 error = rtrequest(RTM_ADD, (struct sockaddr *)&def, 479 (struct sockaddr *)&gate, (struct sockaddr *)&mask, 480 RTF_GATEWAY, &newrt); 481 if (newrt) { 482 nd6_rtmsg(RTM_ADD, newrt); /* tell user process */ 483 RTFREE(newrt); 484 } 485 if (error == 0) 486 new->installed = 1; 487 splx(s); 488 return; 489} 490 491struct nd_defrouter * 492defrouter_lookup(struct in6_addr *addr, struct ifnet *ifp) 493{ 494 INIT_VNET_INET6(ifp->if_vnet); 495 struct nd_defrouter *dr; 496 497 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 498 dr = TAILQ_NEXT(dr, dr_entry)) { 499 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) 500 return (dr); 501 } 502 503 return (NULL); /* search failed */ 504} 505 506/* 507 * Remove the default route for a given router. 508 * This is just a subroutine function for defrouter_select(), and should 509 * not be called from anywhere else. 510 */ 511static void 512defrouter_delreq(struct nd_defrouter *dr) 513{ 514 struct sockaddr_in6 def, mask, gate; 515 struct rtentry *oldrt = NULL; 516 517 bzero(&def, sizeof(def)); 518 bzero(&mask, sizeof(mask)); 519 bzero(&gate, sizeof(gate)); 520 521 def.sin6_len = mask.sin6_len = gate.sin6_len = 522 sizeof(struct sockaddr_in6); 523 def.sin6_family = gate.sin6_family = AF_INET6; 524 gate.sin6_addr = dr->rtaddr; 525 526 rtrequest(RTM_DELETE, (struct sockaddr *)&def, 527 (struct sockaddr *)&gate, 528 (struct sockaddr *)&mask, RTF_GATEWAY, &oldrt); 529 if (oldrt) { 530 nd6_rtmsg(RTM_DELETE, oldrt); 531 RTFREE(oldrt); 532 } 533 534 dr->installed = 0; 535} 536 537/* 538 * remove all default routes from default router list 539 */ 540void 541defrouter_reset(void) 542{ 543 INIT_VNET_INET6(curvnet); 544 struct nd_defrouter *dr; 545 546 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 547 dr = TAILQ_NEXT(dr, dr_entry)) 548 defrouter_delreq(dr); 549 550 /* 551 * XXX should we also nuke any default routers in the kernel, by 552 * going through them by rtalloc1()? 553 */ 554} 555 556void 557defrtrlist_del(struct nd_defrouter *dr) 558{ 559 INIT_VNET_INET6(curvnet); 560 struct nd_defrouter *deldr = NULL; 561 struct nd_prefix *pr; 562 563 /* 564 * Flush all the routing table entries that use the router 565 * as a next hop. 566 */ 567 if (!V_ip6_forwarding && V_ip6_accept_rtadv) /* XXX: better condition? */ 568 rt6_flush(&dr->rtaddr, dr->ifp); 569 570 if (dr->installed) { 571 deldr = dr; 572 defrouter_delreq(dr); 573 } 574 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 575 576 /* 577 * Also delete all the pointers to the router in each prefix lists. 578 */ 579 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 580 struct nd_pfxrouter *pfxrtr; 581 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 582 pfxrtr_del(pfxrtr); 583 } 584 pfxlist_onlink_check(); 585 586 /* 587 * If the router is the primary one, choose a new one. 588 * Note that defrouter_select() will remove the current gateway 589 * from the routing table. 590 */ 591 if (deldr) 592 defrouter_select(); 593 594 free(dr, M_IP6NDP); 595} 596 597/* 598 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 599 * draft-ietf-ipngwg-router-selection: 600 * 1) Routers that are reachable or probably reachable should be preferred. 601 * If we have more than one (probably) reachable router, prefer ones 602 * with the highest router preference. 603 * 2) When no routers on the list are known to be reachable or 604 * probably reachable, routers SHOULD be selected in a round-robin 605 * fashion, regardless of router preference values. 606 * 3) If the Default Router List is empty, assume that all 607 * destinations are on-link. 608 * 609 * We assume nd_defrouter is sorted by router preference value. 610 * Since the code below covers both with and without router preference cases, 611 * we do not need to classify the cases by ifdef. 612 * 613 * At this moment, we do not try to install more than one default router, 614 * even when the multipath routing is available, because we're not sure about 615 * the benefits for stub hosts comparing to the risk of making the code 616 * complicated and the possibility of introducing bugs. 617 */ 618void 619defrouter_select(void) 620{ 621 INIT_VNET_INET6(curvnet); 622 int s = splnet(); 623 struct nd_defrouter *dr, *selected_dr = NULL, *installed_dr = NULL; 624 struct llentry *ln = NULL; 625 626 /* 627 * This function should be called only when acting as an autoconfigured 628 * host. Although the remaining part of this function is not effective 629 * if the node is not an autoconfigured host, we explicitly exclude 630 * such cases here for safety. 631 */ 632 if (V_ip6_forwarding || !V_ip6_accept_rtadv) { 633 nd6log((LOG_WARNING, 634 "defrouter_select: called unexpectedly (forwarding=%d, " 635 "accept_rtadv=%d)\n", V_ip6_forwarding, V_ip6_accept_rtadv)); 636 splx(s); 637 return; 638 } 639 640 /* 641 * Let's handle easy case (3) first: 642 * If default router list is empty, there's nothing to be done. 643 */ 644 if (!TAILQ_FIRST(&V_nd_defrouter)) { 645 splx(s); 646 return; 647 } 648 649 /* 650 * Search for a (probably) reachable router from the list. 651 * We just pick up the first reachable one (if any), assuming that 652 * the ordering rule of the list described in defrtrlist_update(). 653 */ 654 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 655 dr = TAILQ_NEXT(dr, dr_entry)) { 656 IF_AFDATA_LOCK(dr->ifp); 657 if (selected_dr == NULL && 658 (ln = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) && 659 ND6_IS_LLINFO_PROBREACH(ln)) { 660 selected_dr = dr; 661 } 662 IF_AFDATA_UNLOCK(dr->ifp); 663 if (ln != NULL) { 664 LLE_RUNLOCK(ln); 665 ln = NULL; 666 } 667 668 if (dr->installed && installed_dr == NULL) 669 installed_dr = dr; 670 else if (dr->installed && installed_dr) { 671 /* this should not happen. warn for diagnosis. */ 672 log(LOG_ERR, "defrouter_select: more than one router" 673 " is installed\n"); 674 } 675 } 676 /* 677 * If none of the default routers was found to be reachable, 678 * round-robin the list regardless of preference. 679 * Otherwise, if we have an installed router, check if the selected 680 * (reachable) router should really be preferred to the installed one. 681 * We only prefer the new router when the old one is not reachable 682 * or when the new one has a really higher preference value. 683 */ 684 if (selected_dr == NULL) { 685 if (installed_dr == NULL || !TAILQ_NEXT(installed_dr, dr_entry)) 686 selected_dr = TAILQ_FIRST(&V_nd_defrouter); 687 else 688 selected_dr = TAILQ_NEXT(installed_dr, dr_entry); 689 } else if (installed_dr) { 690 IF_AFDATA_LOCK(installed_dr->ifp); 691 if ((ln = nd6_lookup(&installed_dr->rtaddr, 0, installed_dr->ifp)) && 692 ND6_IS_LLINFO_PROBREACH(ln) && 693 rtpref(selected_dr) <= rtpref(installed_dr)) { 694 selected_dr = installed_dr; 695 } 696 IF_AFDATA_UNLOCK(installed_dr->ifp); 697 if (ln != NULL) 698 LLE_RUNLOCK(ln); 699 } 700 701 /* 702 * If the selected router is different than the installed one, 703 * remove the installed router and install the selected one. 704 * Note that the selected router is never NULL here. 705 */ 706 if (installed_dr != selected_dr) { 707 if (installed_dr) 708 defrouter_delreq(installed_dr); 709 defrouter_addreq(selected_dr); 710 } 711 712 splx(s); 713 return; 714} 715 716/* 717 * for default router selection 718 * regards router-preference field as a 2-bit signed integer 719 */ 720static int 721rtpref(struct nd_defrouter *dr) 722{ 723 switch (dr->flags & ND_RA_FLAG_RTPREF_MASK) { 724 case ND_RA_FLAG_RTPREF_HIGH: 725 return (RTPREF_HIGH); 726 case ND_RA_FLAG_RTPREF_MEDIUM: 727 case ND_RA_FLAG_RTPREF_RSV: 728 return (RTPREF_MEDIUM); 729 case ND_RA_FLAG_RTPREF_LOW: 730 return (RTPREF_LOW); 731 default: 732 /* 733 * This case should never happen. If it did, it would mean a 734 * serious bug of kernel internal. We thus always bark here. 735 * Or, can we even panic? 736 */ 737 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->flags); 738 return (RTPREF_INVALID); 739 } 740 /* NOTREACHED */ 741} 742 743static struct nd_defrouter * 744defrtrlist_update(struct nd_defrouter *new) 745{ 746 INIT_VNET_INET6(curvnet); 747 struct nd_defrouter *dr, *n; 748 int s = splnet(); 749 750 if ((dr = defrouter_lookup(&new->rtaddr, new->ifp)) != NULL) { 751 /* entry exists */ 752 if (new->rtlifetime == 0) { 753 defrtrlist_del(dr); 754 dr = NULL; 755 } else { 756 int oldpref = rtpref(dr); 757 758 /* override */ 759 dr->flags = new->flags; /* xxx flag check */ 760 dr->rtlifetime = new->rtlifetime; 761 dr->expire = new->expire; 762 763 /* 764 * If the preference does not change, there's no need 765 * to sort the entries. 766 */ 767 if (rtpref(new) == oldpref) { 768 splx(s); 769 return (dr); 770 } 771 772 /* 773 * preferred router may be changed, so relocate 774 * this router. 775 * XXX: calling TAILQ_REMOVE directly is a bad manner. 776 * However, since defrtrlist_del() has many side 777 * effects, we intentionally do so here. 778 * defrouter_select() below will handle routing 779 * changes later. 780 */ 781 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 782 n = dr; 783 goto insert; 784 } 785 splx(s); 786 return (dr); 787 } 788 789 /* entry does not exist */ 790 if (new->rtlifetime == 0) { 791 splx(s); 792 return (NULL); 793 } 794 795 n = (struct nd_defrouter *)malloc(sizeof(*n), M_IP6NDP, M_NOWAIT); 796 if (n == NULL) { 797 splx(s); 798 return (NULL); 799 } 800 bzero(n, sizeof(*n)); 801 *n = *new; 802 803insert: 804 /* 805 * Insert the new router in the Default Router List; 806 * The Default Router List should be in the descending order 807 * of router-preferece. Routers with the same preference are 808 * sorted in the arriving time order. 809 */ 810 811 /* insert at the end of the group */ 812 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 813 dr = TAILQ_NEXT(dr, dr_entry)) { 814 if (rtpref(n) > rtpref(dr)) 815 break; 816 } 817 if (dr) 818 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 819 else 820 TAILQ_INSERT_TAIL(&V_nd_defrouter, n, dr_entry); 821 822 defrouter_select(); 823 824 splx(s); 825 826 return (n); 827} 828 829static struct nd_pfxrouter * 830pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 831{ 832 struct nd_pfxrouter *search; 833 834 for (search = pr->ndpr_advrtrs.lh_first; search; search = search->pfr_next) { 835 if (search->router == dr) 836 break; 837 } 838 839 return (search); 840} 841 842static void 843pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 844{ 845 struct nd_pfxrouter *new; 846 847 new = (struct nd_pfxrouter *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT); 848 if (new == NULL) 849 return; 850 bzero(new, sizeof(*new)); 851 new->router = dr; 852 853 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 854 855 pfxlist_onlink_check(); 856} 857 858static void 859pfxrtr_del(struct nd_pfxrouter *pfr) 860{ 861 LIST_REMOVE(pfr, pfr_entry); 862 free(pfr, M_IP6NDP); 863} 864 865struct nd_prefix * 866nd6_prefix_lookup(struct nd_prefixctl *key) 867{ 868 INIT_VNET_INET6(curvnet); 869 struct nd_prefix *search; 870 871 for (search = V_nd_prefix.lh_first; 872 search; search = search->ndpr_next) { 873 if (key->ndpr_ifp == search->ndpr_ifp && 874 key->ndpr_plen == search->ndpr_plen && 875 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 876 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 877 break; 878 } 879 } 880 881 return (search); 882} 883 884int 885nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 886 struct nd_prefix **newp) 887{ 888 INIT_VNET_INET6(curvnet); 889 struct nd_prefix *new = NULL; 890 int error = 0; 891 int i, s; 892 char ip6buf[INET6_ADDRSTRLEN]; 893 894 new = (struct nd_prefix *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT); 895 if (new == NULL) 896 return(ENOMEM); 897 bzero(new, sizeof(*new)); 898 new->ndpr_ifp = pr->ndpr_ifp; 899 new->ndpr_prefix = pr->ndpr_prefix; 900 new->ndpr_plen = pr->ndpr_plen; 901 new->ndpr_vltime = pr->ndpr_vltime; 902 new->ndpr_pltime = pr->ndpr_pltime; 903 new->ndpr_flags = pr->ndpr_flags; 904 if ((error = in6_init_prefix_ltimes(new)) != 0) { 905 free(new, M_IP6NDP); 906 return(error); 907 } 908 new->ndpr_lastupdate = time_second; 909 if (newp != NULL) 910 *newp = new; 911 912 /* initialization */ 913 LIST_INIT(&new->ndpr_advrtrs); 914 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 915 /* make prefix in the canonical form */ 916 for (i = 0; i < 4; i++) 917 new->ndpr_prefix.sin6_addr.s6_addr32[i] &= 918 new->ndpr_mask.s6_addr32[i]; 919 920 s = splnet(); 921 /* link ndpr_entry to nd_prefix list */ 922 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry); 923 splx(s); 924 925 /* ND_OPT_PI_FLAG_ONLINK processing */ 926 if (new->ndpr_raf_onlink) { 927 int e; 928 929 if ((e = nd6_prefix_onlink(new)) != 0) { 930 nd6log((LOG_ERR, "nd6_prelist_add: failed to make " 931 "the prefix %s/%d on-link on %s (errno=%d)\n", 932 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 933 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 934 /* proceed anyway. XXX: is it correct? */ 935 } 936 } 937 938 if (dr) 939 pfxrtr_add(new, dr); 940 941 return 0; 942} 943 944void 945prelist_remove(struct nd_prefix *pr) 946{ 947 INIT_VNET_INET6(curvnet); 948 struct nd_pfxrouter *pfr, *next; 949 int e, s; 950 char ip6buf[INET6_ADDRSTRLEN]; 951 952 /* make sure to invalidate the prefix until it is really freed. */ 953 pr->ndpr_vltime = 0; 954 pr->ndpr_pltime = 0; 955 956 /* 957 * Though these flags are now meaningless, we'd rather keep the value 958 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users 959 * when executing "ndp -p". 960 */ 961 962 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 && 963 (e = nd6_prefix_offlink(pr)) != 0) { 964 nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink " 965 "on %s, errno=%d\n", 966 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 967 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 968 /* what should we do? */ 969 } 970 971 if (pr->ndpr_refcnt > 0) 972 return; /* notice here? */ 973 974 s = splnet(); 975 976 /* unlink ndpr_entry from nd_prefix list */ 977 LIST_REMOVE(pr, ndpr_entry); 978 979 /* free list of routers that adversed the prefix */ 980 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; pfr = next) { 981 next = pfr->pfr_next; 982 983 free(pfr, M_IP6NDP); 984 } 985 splx(s); 986 987 free(pr, M_IP6NDP); 988 989 pfxlist_onlink_check(); 990} 991 992/* 993 * dr - may be NULL 994 */ 995 996static int 997prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr, 998 struct mbuf *m, int mcast) 999{ 1000 INIT_VNET_INET6(curvnet); 1001 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 1002 struct ifaddr *ifa; 1003 struct ifnet *ifp = new->ndpr_ifp; 1004 struct nd_prefix *pr; 1005 int s = splnet(); 1006 int error = 0; 1007 int newprefix = 0; 1008 int auth; 1009 struct in6_addrlifetime lt6_tmp; 1010 char ip6buf[INET6_ADDRSTRLEN]; 1011 1012 auth = 0; 1013 if (m) { 1014 /* 1015 * Authenticity for NA consists authentication for 1016 * both IP header and IP datagrams, doesn't it ? 1017 */ 1018#if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1019 auth = ((m->m_flags & M_AUTHIPHDR) && 1020 (m->m_flags & M_AUTHIPDGM)); 1021#endif 1022 } 1023 1024 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1025 /* 1026 * nd6_prefix_lookup() ensures that pr and new have the same 1027 * prefix on a same interface. 1028 */ 1029 1030 /* 1031 * Update prefix information. Note that the on-link (L) bit 1032 * and the autonomous (A) bit should NOT be changed from 1 1033 * to 0. 1034 */ 1035 if (new->ndpr_raf_onlink == 1) 1036 pr->ndpr_raf_onlink = 1; 1037 if (new->ndpr_raf_auto == 1) 1038 pr->ndpr_raf_auto = 1; 1039 if (new->ndpr_raf_onlink) { 1040 pr->ndpr_vltime = new->ndpr_vltime; 1041 pr->ndpr_pltime = new->ndpr_pltime; 1042 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1043 pr->ndpr_lastupdate = time_second; 1044 } 1045 1046 if (new->ndpr_raf_onlink && 1047 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1048 int e; 1049 1050 if ((e = nd6_prefix_onlink(pr)) != 0) { 1051 nd6log((LOG_ERR, 1052 "prelist_update: failed to make " 1053 "the prefix %s/%d on-link on %s " 1054 "(errno=%d)\n", 1055 ip6_sprintf(ip6buf, 1056 &pr->ndpr_prefix.sin6_addr), 1057 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1058 /* proceed anyway. XXX: is it correct? */ 1059 } 1060 } 1061 1062 if (dr && pfxrtr_lookup(pr, dr) == NULL) 1063 pfxrtr_add(pr, dr); 1064 } else { 1065 struct nd_prefix *newpr = NULL; 1066 1067 newprefix = 1; 1068 1069 if (new->ndpr_vltime == 0) 1070 goto end; 1071 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1072 goto end; 1073 1074 error = nd6_prelist_add(new, dr, &newpr); 1075 if (error != 0 || newpr == NULL) { 1076 nd6log((LOG_NOTICE, "prelist_update: " 1077 "nd6_prelist_add failed for %s/%d on %s " 1078 "errno=%d, returnpr=%p\n", 1079 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr), 1080 new->ndpr_plen, if_name(new->ndpr_ifp), 1081 error, newpr)); 1082 goto end; /* we should just give up in this case. */ 1083 } 1084 1085 /* 1086 * XXX: from the ND point of view, we can ignore a prefix 1087 * with the on-link bit being zero. However, we need a 1088 * prefix structure for references from autoconfigured 1089 * addresses. Thus, we explicitly make sure that the prefix 1090 * itself expires now. 1091 */ 1092 if (newpr->ndpr_raf_onlink == 0) { 1093 newpr->ndpr_vltime = 0; 1094 newpr->ndpr_pltime = 0; 1095 in6_init_prefix_ltimes(newpr); 1096 } 1097 1098 pr = newpr; 1099 } 1100 1101 /* 1102 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1103 * Note that pr must be non NULL at this point. 1104 */ 1105 1106 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1107 if (!new->ndpr_raf_auto) 1108 goto end; 1109 1110 /* 1111 * 5.5.3 (b). the link-local prefix should have been ignored in 1112 * nd6_ra_input. 1113 */ 1114 1115 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1116 if (new->ndpr_pltime > new->ndpr_vltime) { 1117 error = EINVAL; /* XXX: won't be used */ 1118 goto end; 1119 } 1120 1121 /* 1122 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1123 * an address configured by stateless autoconfiguration already in the 1124 * list of addresses associated with the interface, and the Valid 1125 * Lifetime is not 0, form an address. We first check if we have 1126 * a matching prefix. 1127 * Note: we apply a clarification in rfc2462bis-02 here. We only 1128 * consider autoconfigured addresses while RFC2462 simply said 1129 * "address". 1130 */ 1131 IF_ADDR_LOCK(ifp); 1132 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1133 struct in6_ifaddr *ifa6; 1134 u_int32_t remaininglifetime; 1135 1136 if (ifa->ifa_addr->sa_family != AF_INET6) 1137 continue; 1138 1139 ifa6 = (struct in6_ifaddr *)ifa; 1140 1141 /* 1142 * We only consider autoconfigured addresses as per rfc2462bis. 1143 */ 1144 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1145 continue; 1146 1147 /* 1148 * Spec is not clear here, but I believe we should concentrate 1149 * on unicast (i.e. not anycast) addresses. 1150 * XXX: other ia6_flags? detached or duplicated? 1151 */ 1152 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1153 continue; 1154 1155 /* 1156 * Ignore the address if it is not associated with a prefix 1157 * or is associated with a prefix that is different from this 1158 * one. (pr is never NULL here) 1159 */ 1160 if (ifa6->ia6_ndpr != pr) 1161 continue; 1162 1163 if (ia6_match == NULL) /* remember the first one */ 1164 ia6_match = ifa6; 1165 1166 /* 1167 * An already autoconfigured address matched. Now that we 1168 * are sure there is at least one matched address, we can 1169 * proceed to 5.5.3. (e): update the lifetimes according to the 1170 * "two hours" rule and the privacy extension. 1171 * We apply some clarifications in rfc2462bis: 1172 * - use remaininglifetime instead of storedlifetime as a 1173 * variable name 1174 * - remove the dead code in the "two-hour" rule 1175 */ 1176#define TWOHOUR (120*60) 1177 lt6_tmp = ifa6->ia6_lifetime; 1178 1179 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1180 remaininglifetime = ND6_INFINITE_LIFETIME; 1181 else if (time_second - ifa6->ia6_updatetime > 1182 lt6_tmp.ia6t_vltime) { 1183 /* 1184 * The case of "invalid" address. We should usually 1185 * not see this case. 1186 */ 1187 remaininglifetime = 0; 1188 } else 1189 remaininglifetime = lt6_tmp.ia6t_vltime - 1190 (time_second - ifa6->ia6_updatetime); 1191 1192 /* when not updating, keep the current stored lifetime. */ 1193 lt6_tmp.ia6t_vltime = remaininglifetime; 1194 1195 if (TWOHOUR < new->ndpr_vltime || 1196 remaininglifetime < new->ndpr_vltime) { 1197 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1198 } else if (remaininglifetime <= TWOHOUR) { 1199 if (auth) { 1200 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1201 } 1202 } else { 1203 /* 1204 * new->ndpr_vltime <= TWOHOUR && 1205 * TWOHOUR < remaininglifetime 1206 */ 1207 lt6_tmp.ia6t_vltime = TWOHOUR; 1208 } 1209 1210 /* The 2 hour rule is not imposed for preferred lifetime. */ 1211 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1212 1213 in6_init_address_ltimes(pr, <6_tmp); 1214 1215 /* 1216 * We need to treat lifetimes for temporary addresses 1217 * differently, according to 1218 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1219 * we only update the lifetimes when they are in the maximum 1220 * intervals. 1221 */ 1222 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1223 u_int32_t maxvltime, maxpltime; 1224 1225 if (V_ip6_temp_valid_lifetime > 1226 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1227 V_ip6_desync_factor)) { 1228 maxvltime = V_ip6_temp_valid_lifetime - 1229 (time_second - ifa6->ia6_createtime) - 1230 V_ip6_desync_factor; 1231 } else 1232 maxvltime = 0; 1233 if (V_ip6_temp_preferred_lifetime > 1234 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1235 V_ip6_desync_factor)) { 1236 maxpltime = V_ip6_temp_preferred_lifetime - 1237 (time_second - ifa6->ia6_createtime) - 1238 V_ip6_desync_factor; 1239 } else 1240 maxpltime = 0; 1241 1242 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1243 lt6_tmp.ia6t_vltime > maxvltime) { 1244 lt6_tmp.ia6t_vltime = maxvltime; 1245 } 1246 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1247 lt6_tmp.ia6t_pltime > maxpltime) { 1248 lt6_tmp.ia6t_pltime = maxpltime; 1249 } 1250 } 1251 ifa6->ia6_lifetime = lt6_tmp; 1252 ifa6->ia6_updatetime = time_second; 1253 } 1254 IF_ADDR_UNLOCK(ifp); 1255 if (ia6_match == NULL && new->ndpr_vltime) { 1256 int ifidlen; 1257 1258 /* 1259 * 5.5.3 (d) (continued) 1260 * No address matched and the valid lifetime is non-zero. 1261 * Create a new address. 1262 */ 1263 1264 /* 1265 * Prefix Length check: 1266 * If the sum of the prefix length and interface identifier 1267 * length does not equal 128 bits, the Prefix Information 1268 * option MUST be ignored. The length of the interface 1269 * identifier is defined in a separate link-type specific 1270 * document. 1271 */ 1272 ifidlen = in6_if2idlen(ifp); 1273 if (ifidlen < 0) { 1274 /* this should not happen, so we always log it. */ 1275 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1276 if_name(ifp)); 1277 goto end; 1278 } 1279 if (ifidlen + pr->ndpr_plen != 128) { 1280 nd6log((LOG_INFO, 1281 "prelist_update: invalid prefixlen " 1282 "%d for %s, ignored\n", 1283 pr->ndpr_plen, if_name(ifp))); 1284 goto end; 1285 } 1286 1287 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1288 /* 1289 * note that we should use pr (not new) for reference. 1290 */ 1291 pr->ndpr_refcnt++; 1292 ia6->ia6_ndpr = pr; 1293 1294 /* 1295 * RFC 3041 3.3 (2). 1296 * When a new public address is created as described 1297 * in RFC2462, also create a new temporary address. 1298 * 1299 * RFC 3041 3.5. 1300 * When an interface connects to a new link, a new 1301 * randomized interface identifier should be generated 1302 * immediately together with a new set of temporary 1303 * addresses. Thus, we specifiy 1 as the 2nd arg of 1304 * in6_tmpifadd(). 1305 */ 1306 if (V_ip6_use_tempaddr) { 1307 int e; 1308 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1309 nd6log((LOG_NOTICE, "prelist_update: " 1310 "failed to create a temporary " 1311 "address, errno=%d\n", 1312 e)); 1313 } 1314 } 1315 ifa_free(&ia6->ia_ifa); 1316 1317 /* 1318 * A newly added address might affect the status 1319 * of other addresses, so we check and update it. 1320 * XXX: what if address duplication happens? 1321 */ 1322 pfxlist_onlink_check(); 1323 } else { 1324 /* just set an error. do not bark here. */ 1325 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1326 } 1327 } 1328 1329 end: 1330 splx(s); 1331 return error; 1332} 1333 1334/* 1335 * A supplement function used in the on-link detection below; 1336 * detect if a given prefix has a (probably) reachable advertising router. 1337 * XXX: lengthy function name... 1338 */ 1339static struct nd_pfxrouter * 1340find_pfxlist_reachable_router(struct nd_prefix *pr) 1341{ 1342 struct nd_pfxrouter *pfxrtr; 1343 struct llentry *ln; 1344 int canreach; 1345 1346 for (pfxrtr = LIST_FIRST(&pr->ndpr_advrtrs); pfxrtr != NULL; 1347 pfxrtr = LIST_NEXT(pfxrtr, pfr_entry)) { 1348 IF_AFDATA_LOCK(pfxrtr->router->ifp); 1349 ln = nd6_lookup(&pfxrtr->router->rtaddr, 0, pfxrtr->router->ifp); 1350 IF_AFDATA_UNLOCK(pfxrtr->router->ifp); 1351 if (ln == NULL) 1352 continue; 1353 canreach = ND6_IS_LLINFO_PROBREACH(ln); 1354 LLE_RUNLOCK(ln); 1355 if (canreach) 1356 break; 1357 } 1358 return (pfxrtr); 1359} 1360 1361/* 1362 * Check if each prefix in the prefix list has at least one available router 1363 * that advertised the prefix (a router is "available" if its neighbor cache 1364 * entry is reachable or probably reachable). 1365 * If the check fails, the prefix may be off-link, because, for example, 1366 * we have moved from the network but the lifetime of the prefix has not 1367 * expired yet. So we should not use the prefix if there is another prefix 1368 * that has an available router. 1369 * But, if there is no prefix that has an available router, we still regards 1370 * all the prefixes as on-link. This is because we can't tell if all the 1371 * routers are simply dead or if we really moved from the network and there 1372 * is no router around us. 1373 */ 1374void 1375pfxlist_onlink_check() 1376{ 1377 INIT_VNET_INET6(curvnet); 1378 struct nd_prefix *pr; 1379 struct in6_ifaddr *ifa; 1380 struct nd_defrouter *dr; 1381 struct nd_pfxrouter *pfxrtr = NULL; 1382 1383 /* 1384 * Check if there is a prefix that has a reachable advertising 1385 * router. 1386 */ 1387 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1388 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1389 break; 1390 } 1391 1392 /* 1393 * If we have no such prefix, check whether we still have a router 1394 * that does not advertise any prefixes. 1395 */ 1396 if (pr == NULL) { 1397 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 1398 dr = TAILQ_NEXT(dr, dr_entry)) { 1399 struct nd_prefix *pr0; 1400 1401 for (pr0 = V_nd_prefix.lh_first; pr0; 1402 pr0 = pr0->ndpr_next) { 1403 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1404 break; 1405 } 1406 if (pfxrtr != NULL) 1407 break; 1408 } 1409 } 1410 if (pr != NULL || (TAILQ_FIRST(&V_nd_defrouter) && pfxrtr == NULL)) { 1411 /* 1412 * There is at least one prefix that has a reachable router, 1413 * or at least a router which probably does not advertise 1414 * any prefixes. The latter would be the case when we move 1415 * to a new link where we have a router that does not provide 1416 * prefixes and we configure an address by hand. 1417 * Detach prefixes which have no reachable advertising 1418 * router, and attach other prefixes. 1419 */ 1420 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1421 /* XXX: a link-local prefix should never be detached */ 1422 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1423 continue; 1424 1425 /* 1426 * we aren't interested in prefixes without the L bit 1427 * set. 1428 */ 1429 if (pr->ndpr_raf_onlink == 0) 1430 continue; 1431 1432 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1433 find_pfxlist_reachable_router(pr) == NULL) 1434 pr->ndpr_stateflags |= NDPRF_DETACHED; 1435 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1436 find_pfxlist_reachable_router(pr) != 0) 1437 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1438 } 1439 } else { 1440 /* there is no prefix that has a reachable router */ 1441 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1442 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1443 continue; 1444 1445 if (pr->ndpr_raf_onlink == 0) 1446 continue; 1447 1448 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1449 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1450 } 1451 } 1452 1453 /* 1454 * Remove each interface route associated with a (just) detached 1455 * prefix, and reinstall the interface route for a (just) attached 1456 * prefix. Note that all attempt of reinstallation does not 1457 * necessarily success, when a same prefix is shared among multiple 1458 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1459 * so we don't have to care about them. 1460 */ 1461 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1462 int e; 1463 char ip6buf[INET6_ADDRSTRLEN]; 1464 1465 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1466 continue; 1467 1468 if (pr->ndpr_raf_onlink == 0) 1469 continue; 1470 1471 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1472 (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1473 if ((e = nd6_prefix_offlink(pr)) != 0) { 1474 nd6log((LOG_ERR, 1475 "pfxlist_onlink_check: failed to " 1476 "make %s/%d offlink, errno=%d\n", 1477 ip6_sprintf(ip6buf, 1478 &pr->ndpr_prefix.sin6_addr), 1479 pr->ndpr_plen, e)); 1480 } 1481 } 1482 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1483 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 && 1484 pr->ndpr_raf_onlink) { 1485 if ((e = nd6_prefix_onlink(pr)) != 0) { 1486 nd6log((LOG_ERR, 1487 "pfxlist_onlink_check: failed to " 1488 "make %s/%d onlink, errno=%d\n", 1489 ip6_sprintf(ip6buf, 1490 &pr->ndpr_prefix.sin6_addr), 1491 pr->ndpr_plen, e)); 1492 } 1493 } 1494 } 1495 1496 /* 1497 * Changes on the prefix status might affect address status as well. 1498 * Make sure that all addresses derived from an attached prefix are 1499 * attached, and that all addresses derived from a detached prefix are 1500 * detached. Note, however, that a manually configured address should 1501 * always be attached. 1502 * The precise detection logic is same as the one for prefixes. 1503 */ 1504 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1505 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1506 continue; 1507 1508 if (ifa->ia6_ndpr == NULL) { 1509 /* 1510 * This can happen when we first configure the address 1511 * (i.e. the address exists, but the prefix does not). 1512 * XXX: complicated relationships... 1513 */ 1514 continue; 1515 } 1516 1517 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1518 break; 1519 } 1520 if (ifa) { 1521 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1522 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1523 continue; 1524 1525 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1526 continue; 1527 1528 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 1529 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1530 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1531 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1532 nd6_dad_start((struct ifaddr *)ifa, 0); 1533 } 1534 } else { 1535 ifa->ia6_flags |= IN6_IFF_DETACHED; 1536 } 1537 } 1538 } 1539 else { 1540 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1541 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1542 continue; 1543 1544 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1545 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1546 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1547 /* Do we need a delay in this case? */ 1548 nd6_dad_start((struct ifaddr *)ifa, 0); 1549 } 1550 } 1551 } 1552} 1553 1554int 1555nd6_prefix_onlink(struct nd_prefix *pr) 1556{ 1557 INIT_VNET_INET6(curvnet); 1558 struct ifaddr *ifa; 1559 struct ifnet *ifp = pr->ndpr_ifp; 1560 struct sockaddr_in6 mask6; 1561 struct nd_prefix *opr; 1562 u_long rtflags; 1563 int error = 0; 1564 struct radix_node_head *rnh; 1565 struct rtentry *rt = NULL; 1566 char ip6buf[INET6_ADDRSTRLEN]; 1567 struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 1568 1569 /* sanity check */ 1570 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1571 nd6log((LOG_ERR, 1572 "nd6_prefix_onlink: %s/%d is already on-link\n", 1573 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1574 pr->ndpr_plen)); 1575 return (EEXIST); 1576 } 1577 1578 /* 1579 * Add the interface route associated with the prefix. Before 1580 * installing the route, check if there's the same prefix on another 1581 * interface, and the prefix has already installed the interface route. 1582 * Although such a configuration is expected to be rare, we explicitly 1583 * allow it. 1584 */ 1585 for (opr = V_nd_prefix.lh_first; opr; opr = opr->ndpr_next) { 1586 if (opr == pr) 1587 continue; 1588 1589 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 1590 continue; 1591 1592 if (opr->ndpr_plen == pr->ndpr_plen && 1593 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1594 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) 1595 return (0); 1596 } 1597 1598 /* 1599 * We prefer link-local addresses as the associated interface address. 1600 */ 1601 /* search for a link-local addr */ 1602 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 1603 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 1604 if (ifa == NULL) { 1605 /* XXX: freebsd does not have ifa_ifwithaf */ 1606 IF_ADDR_LOCK(ifp); 1607 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1608 if (ifa->ifa_addr->sa_family == AF_INET6) 1609 break; 1610 } 1611 if (ifa != NULL) 1612 ifa_ref(ifa); 1613 IF_ADDR_UNLOCK(ifp); 1614 /* should we care about ia6_flags? */ 1615 } 1616 if (ifa == NULL) { 1617 /* 1618 * This can still happen, when, for example, we receive an RA 1619 * containing a prefix with the L bit set and the A bit clear, 1620 * after removing all IPv6 addresses on the receiving 1621 * interface. This should, of course, be rare though. 1622 */ 1623 nd6log((LOG_NOTICE, 1624 "nd6_prefix_onlink: failed to find any ifaddr" 1625 " to add route for a prefix(%s/%d) on %s\n", 1626 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1627 pr->ndpr_plen, if_name(ifp))); 1628 return (0); 1629 } 1630 1631 /* 1632 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs. 1633 * ifa->ifa_rtrequest = nd6_rtrequest; 1634 */ 1635 bzero(&mask6, sizeof(mask6)); 1636 mask6.sin6_len = sizeof(mask6); 1637 mask6.sin6_addr = pr->ndpr_mask; 1638 rtflags = ifa->ifa_flags | RTF_UP; 1639 error = rtrequest(RTM_ADD, (struct sockaddr *)&pr->ndpr_prefix, 1640 ifa->ifa_addr, (struct sockaddr *)&mask6, rtflags, &rt); 1641 if (error == 0) { 1642 if (rt != NULL) /* this should be non NULL, though */ { 1643 rnh = rt_tables_get_rnh(rt->rt_fibnum, AF_INET6); 1644 /* XXX what if rhn == NULL? */ 1645 RADIX_NODE_HEAD_LOCK(rnh); 1646 RT_LOCK(rt); 1647 if (!rt_setgate(rt, rt_key(rt), (struct sockaddr *)&null_sdl)) { 1648 ((struct sockaddr_dl *)rt->rt_gateway)->sdl_type = 1649 rt->rt_ifp->if_type; 1650 ((struct sockaddr_dl *)rt->rt_gateway)->sdl_index = 1651 rt->rt_ifp->if_index; 1652 } 1653 RADIX_NODE_HEAD_UNLOCK(rnh); 1654 nd6_rtmsg(RTM_ADD, rt); 1655 RT_UNLOCK(rt); 1656 } 1657 pr->ndpr_stateflags |= NDPRF_ONLINK; 1658 } else { 1659 char ip6bufg[INET6_ADDRSTRLEN], ip6bufm[INET6_ADDRSTRLEN]; 1660 nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add route for a" 1661 " prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx " 1662 "errno = %d\n", 1663 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1664 pr->ndpr_plen, if_name(ifp), 1665 ip6_sprintf(ip6bufg, &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr), 1666 ip6_sprintf(ip6bufm, &mask6.sin6_addr), rtflags, error)); 1667 } 1668 1669 if (rt != NULL) { 1670 RT_LOCK(rt); 1671 RT_REMREF(rt); 1672 RT_UNLOCK(rt); 1673 } 1674 if (ifa != NULL) 1675 ifa_free(ifa); 1676 1677 return (error); 1678} 1679 1680int 1681nd6_prefix_offlink(struct nd_prefix *pr) 1682{ 1683 INIT_VNET_INET6(curvnet); 1684 int error = 0; 1685 struct ifnet *ifp = pr->ndpr_ifp; 1686 struct nd_prefix *opr; 1687 struct sockaddr_in6 sa6, mask6; 1688 struct rtentry *rt = NULL; 1689 char ip6buf[INET6_ADDRSTRLEN]; 1690 1691 /* sanity check */ 1692 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1693 nd6log((LOG_ERR, 1694 "nd6_prefix_offlink: %s/%d is already off-link\n", 1695 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1696 pr->ndpr_plen)); 1697 return (EEXIST); 1698 } 1699 1700 bzero(&sa6, sizeof(sa6)); 1701 sa6.sin6_family = AF_INET6; 1702 sa6.sin6_len = sizeof(sa6); 1703 bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr, 1704 sizeof(struct in6_addr)); 1705 bzero(&mask6, sizeof(mask6)); 1706 mask6.sin6_family = AF_INET6; 1707 mask6.sin6_len = sizeof(sa6); 1708 bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr)); 1709 error = rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL, 1710 (struct sockaddr *)&mask6, 0, &rt); 1711 if (error == 0) { 1712 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 1713 1714 /* report the route deletion to the routing socket. */ 1715 if (rt != NULL) 1716 nd6_rtmsg(RTM_DELETE, rt); 1717 1718 /* 1719 * There might be the same prefix on another interface, 1720 * the prefix which could not be on-link just because we have 1721 * the interface route (see comments in nd6_prefix_onlink). 1722 * If there's one, try to make the prefix on-link on the 1723 * interface. 1724 */ 1725 for (opr = V_nd_prefix.lh_first; opr; opr = opr->ndpr_next) { 1726 if (opr == pr) 1727 continue; 1728 1729 if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0) 1730 continue; 1731 1732 /* 1733 * KAME specific: detached prefixes should not be 1734 * on-link. 1735 */ 1736 if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1737 continue; 1738 1739 if (opr->ndpr_plen == pr->ndpr_plen && 1740 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1741 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 1742 int e; 1743 1744 if ((e = nd6_prefix_onlink(opr)) != 0) { 1745 nd6log((LOG_ERR, 1746 "nd6_prefix_offlink: failed to " 1747 "recover a prefix %s/%d from %s " 1748 "to %s (errno = %d)\n", 1749 ip6_sprintf(ip6buf, 1750 &opr->ndpr_prefix.sin6_addr), 1751 opr->ndpr_plen, if_name(ifp), 1752 if_name(opr->ndpr_ifp), e)); 1753 } 1754 } 1755 } 1756 } else { 1757 /* XXX: can we still set the NDPRF_ONLINK flag? */ 1758 nd6log((LOG_ERR, 1759 "nd6_prefix_offlink: failed to delete route: " 1760 "%s/%d on %s (errno = %d)\n", 1761 ip6_sprintf(ip6buf, &sa6.sin6_addr), pr->ndpr_plen, 1762 if_name(ifp), error)); 1763 } 1764 1765 if (rt != NULL) { 1766 RTFREE(rt); 1767 } 1768 1769 return (error); 1770} 1771 1772static struct in6_ifaddr * 1773in6_ifadd(struct nd_prefixctl *pr, int mcast) 1774{ 1775 INIT_VNET_INET6(curvnet); 1776 struct ifnet *ifp = pr->ndpr_ifp; 1777 struct ifaddr *ifa; 1778 struct in6_aliasreq ifra; 1779 struct in6_ifaddr *ia, *ib; 1780 int error, plen0; 1781 struct in6_addr mask; 1782 int prefixlen = pr->ndpr_plen; 1783 int updateflags; 1784 char ip6buf[INET6_ADDRSTRLEN]; 1785 1786 in6_prefixlen2mask(&mask, prefixlen); 1787 1788 /* 1789 * find a link-local address (will be interface ID). 1790 * Is it really mandatory? Theoretically, a global or a site-local 1791 * address can be configured without a link-local address, if we 1792 * have a unique interface identifier... 1793 * 1794 * it is not mandatory to have a link-local address, we can generate 1795 * interface identifier on the fly. we do this because: 1796 * (1) it should be the easiest way to find interface identifier. 1797 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1798 * for multiple addresses on a single interface, and possible shortcut 1799 * of DAD. we omitted DAD for this reason in the past. 1800 * (3) a user can prevent autoconfiguration of global address 1801 * by removing link-local address by hand (this is partly because we 1802 * don't have other way to control the use of IPv6 on an interface. 1803 * this has been our design choice - cf. NRL's "ifconfig auto"). 1804 * (4) it is easier to manage when an interface has addresses 1805 * with the same interface identifier, than to have multiple addresses 1806 * with different interface identifiers. 1807 */ 1808 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1809 if (ifa) 1810 ib = (struct in6_ifaddr *)ifa; 1811 else 1812 return NULL; 1813 1814 /* prefixlen + ifidlen must be equal to 128 */ 1815 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1816 if (prefixlen != plen0) { 1817 ifa_free(ifa); 1818 nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s " 1819 "(prefix=%d ifid=%d)\n", 1820 if_name(ifp), prefixlen, 128 - plen0)); 1821 return NULL; 1822 } 1823 1824 /* make ifaddr */ 1825 1826 bzero(&ifra, sizeof(ifra)); 1827 /* 1828 * in6_update_ifa() does not use ifra_name, but we accurately set it 1829 * for safety. 1830 */ 1831 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1832 ifra.ifra_addr.sin6_family = AF_INET6; 1833 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 1834 /* prefix */ 1835 ifra.ifra_addr.sin6_addr = pr->ndpr_prefix.sin6_addr; 1836 ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0]; 1837 ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1]; 1838 ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2]; 1839 ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3]; 1840 1841 /* interface ID */ 1842 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1843 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1844 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1845 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1846 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1847 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1848 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1849 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1850 ifa_free(ifa); 1851 1852 /* new prefix mask. */ 1853 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); 1854 ifra.ifra_prefixmask.sin6_family = AF_INET6; 1855 bcopy(&mask, &ifra.ifra_prefixmask.sin6_addr, 1856 sizeof(ifra.ifra_prefixmask.sin6_addr)); 1857 1858 /* lifetimes. */ 1859 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1860 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1861 1862 /* XXX: scope zone ID? */ 1863 1864 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1865 1866 /* 1867 * Make sure that we do not have this address already. This should 1868 * usually not happen, but we can still see this case, e.g., if we 1869 * have manually configured the exact address to be configured. 1870 */ 1871 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 1872 &ifra.ifra_addr.sin6_addr); 1873 if (ifa != NULL) { 1874 ifa_free(ifa); 1875 /* this should be rare enough to make an explicit log */ 1876 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1877 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr)); 1878 return (NULL); 1879 } 1880 1881 /* 1882 * Allocate ifaddr structure, link into chain, etc. 1883 * If we are going to create a new address upon receiving a multicasted 1884 * RA, we need to impose a random delay before starting DAD. 1885 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1886 */ 1887 updateflags = 0; 1888 if (mcast) 1889 updateflags |= IN6_IFAUPDATE_DADDELAY; 1890 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 1891 nd6log((LOG_ERR, 1892 "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n", 1893 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr), 1894 if_name(ifp), error)); 1895 return (NULL); /* ifaddr must not have been allocated. */ 1896 } 1897 1898 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1899 /* 1900 * XXXRW: Assumption of non-NULLness here might not be true with 1901 * fine-grained locking -- should we validate it? Or just return 1902 * earlier ifa rather than looking it up again? 1903 */ 1904 return (ia); /* this is always non-NULL and referenced. */ 1905} 1906 1907/* 1908 * ia0 - corresponding public address 1909 */ 1910int 1911in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay) 1912{ 1913 INIT_VNET_INET6(curvnet); 1914 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 1915 struct in6_ifaddr *newia, *ia; 1916 struct in6_aliasreq ifra; 1917 int i, error; 1918 int trylimit = 3; /* XXX: adhoc value */ 1919 int updateflags; 1920 u_int32_t randid[2]; 1921 time_t vltime0, pltime0; 1922 1923 bzero(&ifra, sizeof(ifra)); 1924 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1925 ifra.ifra_addr = ia0->ia_addr; 1926 /* copy prefix mask */ 1927 ifra.ifra_prefixmask = ia0->ia_prefixmask; 1928 /* clear the old IFID */ 1929 for (i = 0; i < 4; i++) { 1930 ifra.ifra_addr.sin6_addr.s6_addr32[i] &= 1931 ifra.ifra_prefixmask.sin6_addr.s6_addr32[i]; 1932 } 1933 1934 again: 1935 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 1936 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 1937 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good " 1938 "random IFID\n")); 1939 return (EINVAL); 1940 } 1941 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1942 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 1943 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1944 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 1945 1946 /* 1947 * in6_get_tmpifid() quite likely provided a unique interface ID. 1948 * However, we may still have a chance to see collision, because 1949 * there may be a time lag between generation of the ID and generation 1950 * of the address. So, we'll do one more sanity check. 1951 */ 1952 TAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) { 1953 if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, 1954 &ifra.ifra_addr.sin6_addr)) { 1955 if (trylimit-- == 0) { 1956 /* 1957 * Give up. Something strange should have 1958 * happened. 1959 */ 1960 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to " 1961 "find a unique random IFID\n")); 1962 return (EEXIST); 1963 } 1964 forcegen = 1; 1965 goto again; 1966 } 1967 } 1968 1969 /* 1970 * The Valid Lifetime is the lower of the Valid Lifetime of the 1971 * public address or TEMP_VALID_LIFETIME. 1972 * The Preferred Lifetime is the lower of the Preferred Lifetime 1973 * of the public address or TEMP_PREFERRED_LIFETIME - 1974 * DESYNC_FACTOR. 1975 */ 1976 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 1977 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 1978 (ia0->ia6_lifetime.ia6t_vltime - 1979 (time_second - ia0->ia6_updatetime)); 1980 if (vltime0 > V_ip6_temp_valid_lifetime) 1981 vltime0 = V_ip6_temp_valid_lifetime; 1982 } else 1983 vltime0 = V_ip6_temp_valid_lifetime; 1984 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 1985 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 1986 (ia0->ia6_lifetime.ia6t_pltime - 1987 (time_second - ia0->ia6_updatetime)); 1988 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){ 1989 pltime0 = V_ip6_temp_preferred_lifetime - 1990 V_ip6_desync_factor; 1991 } 1992 } else 1993 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor; 1994 ifra.ifra_lifetime.ia6t_vltime = vltime0; 1995 ifra.ifra_lifetime.ia6t_pltime = pltime0; 1996 1997 /* 1998 * A temporary address is created only if this calculated Preferred 1999 * Lifetime is greater than REGEN_ADVANCE time units. 2000 */ 2001 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance) 2002 return (0); 2003 2004 /* XXX: scope zone ID? */ 2005 2006 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2007 2008 /* allocate ifaddr structure, link into chain, etc. */ 2009 updateflags = 0; 2010 if (delay) 2011 updateflags |= IN6_IFAUPDATE_DADDELAY; 2012 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 2013 return (error); 2014 2015 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2016 if (newia == NULL) { /* XXX: can it happen? */ 2017 nd6log((LOG_ERR, 2018 "in6_tmpifadd: ifa update succeeded, but we got " 2019 "no ifaddr\n")); 2020 return (EINVAL); /* XXX */ 2021 } 2022 newia->ia6_ndpr = ia0->ia6_ndpr; 2023 newia->ia6_ndpr->ndpr_refcnt++; 2024 ifa_free(&newia->ia_ifa); 2025 2026 /* 2027 * A newly added address might affect the status of other addresses. 2028 * XXX: when the temporary address is generated with a new public 2029 * address, the onlink check is redundant. However, it would be safe 2030 * to do the check explicitly everywhere a new address is generated, 2031 * and, in fact, we surely need the check when we create a new 2032 * temporary address due to deprecation of an old temporary address. 2033 */ 2034 pfxlist_onlink_check(); 2035 2036 return (0); 2037} 2038 2039static int 2040in6_init_prefix_ltimes(struct nd_prefix *ndpr) 2041{ 2042 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 2043 ndpr->ndpr_preferred = 0; 2044 else 2045 ndpr->ndpr_preferred = time_second + ndpr->ndpr_pltime; 2046 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2047 ndpr->ndpr_expire = 0; 2048 else 2049 ndpr->ndpr_expire = time_second + ndpr->ndpr_vltime; 2050 2051 return 0; 2052} 2053 2054static void 2055in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6) 2056{ 2057 /* init ia6t_expire */ 2058 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 2059 lt6->ia6t_expire = 0; 2060 else { 2061 lt6->ia6t_expire = time_second; 2062 lt6->ia6t_expire += lt6->ia6t_vltime; 2063 } 2064 2065 /* init ia6t_preferred */ 2066 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 2067 lt6->ia6t_preferred = 0; 2068 else { 2069 lt6->ia6t_preferred = time_second; 2070 lt6->ia6t_preferred += lt6->ia6t_pltime; 2071 } 2072} 2073 2074/* 2075 * Delete all the routing table entries that use the specified gateway. 2076 * XXX: this function causes search through all entries of routing table, so 2077 * it shouldn't be called when acting as a router. 2078 */ 2079void 2080rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2081{ 2082 struct radix_node_head *rnh; 2083 int s = splnet(); 2084 2085 /* We'll care only link-local addresses */ 2086 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) { 2087 splx(s); 2088 return; 2089 } 2090 2091 rnh = rt_tables_get_rnh(0, AF_INET6); 2092 if (rnh == NULL) 2093 return; 2094 2095 RADIX_NODE_HEAD_LOCK(rnh); 2096 rnh->rnh_walktree(rnh, rt6_deleteroute, (void *)gateway); 2097 RADIX_NODE_HEAD_UNLOCK(rnh); 2098 splx(s); 2099} 2100 2101static int 2102rt6_deleteroute(struct radix_node *rn, void *arg) 2103{ 2104#define SIN6(s) ((struct sockaddr_in6 *)s) 2105 struct rtentry *rt = (struct rtentry *)rn; 2106 struct in6_addr *gate = (struct in6_addr *)arg; 2107 2108 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6) 2109 return (0); 2110 2111 if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) { 2112 return (0); 2113 } 2114 2115 /* 2116 * Do not delete a static route. 2117 * XXX: this seems to be a bit ad-hoc. Should we consider the 2118 * 'cloned' bit instead? 2119 */ 2120 if ((rt->rt_flags & RTF_STATIC) != 0) 2121 return (0); 2122 2123 /* 2124 * We delete only host route. This means, in particular, we don't 2125 * delete default route. 2126 */ 2127 if ((rt->rt_flags & RTF_HOST) == 0) 2128 return (0); 2129 2130 return (rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, 2131 rt_mask(rt), rt->rt_flags, 0)); 2132#undef SIN6 2133} 2134 2135int 2136nd6_setdefaultiface(int ifindex) 2137{ 2138 INIT_VNET_NET(curvnet); 2139 INIT_VNET_INET6(curvnet); 2140 int error = 0; 2141 2142 if (ifindex < 0 || V_if_index < ifindex) 2143 return (EINVAL); 2144 if (ifindex != 0 && !ifnet_byindex(ifindex)) 2145 return (EINVAL); 2146 2147 if (V_nd6_defifindex != ifindex) { 2148 V_nd6_defifindex = ifindex; 2149 if (V_nd6_defifindex > 0) 2150 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex); 2151 else 2152 V_nd6_defifp = NULL; 2153 2154 /* 2155 * Our current implementation assumes one-to-one maping between 2156 * interfaces and links, so it would be natural to use the 2157 * default interface as the default link. 2158 */ 2159 scope6_setdefault(V_nd6_defifp); 2160 } 2161 2162 return (error); 2163} 2164