1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $KAME: nd6_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $ 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/refcount.h> 45 #include <sys/socket.h> 46 #include <sys/sockio.h> 47 #include <sys/time.h> 48 #include <sys/kernel.h> 49 #include <sys/lock.h> 50 #include <sys/errno.h> 51 #include <sys/rmlock.h> 52 #include <sys/rwlock.h> 53 #include <sys/sysctl.h> 54 #include <sys/syslog.h> 55 #include <sys/queue.h> 56 57 #include <net/if.h> 58 #include <net/if_var.h> 59 #include <net/if_types.h> 60 #include <net/if_dl.h> 61 #include <net/route.h> 62 #include <net/route/nhop.h> 63 #include <net/route/route_ctl.h> 64 #include <net/route/route_var.h> 65 #include <net/radix.h> 66 #include <net/vnet.h> 67 68 #include <netinet/in.h> 69 #include <net/if_llatbl.h> 70 #include <netinet6/in6_var.h> 71 #include <netinet6/in6_ifattach.h> 72 #include <netinet/ip6.h> 73 #include <netinet6/ip6_var.h> 74 #include <netinet6/nd6.h> 75 #include <netinet/icmp6.h> 76 #include <netinet6/scope6_var.h> 77 78 static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 79 static int prelist_update(struct nd_prefixctl *, struct nd_defrouter *, 80 struct mbuf *, int); 81 static int nd6_prefix_onlink(struct nd_prefix *); 82 83 TAILQ_HEAD(nd6_drhead, nd_defrouter); 84 VNET_DEFINE_STATIC(struct nd6_drhead, nd6_defrouter); 85 #define V_nd6_defrouter VNET(nd6_defrouter) 86 87 VNET_DECLARE(int, nd6_recalc_reachtm_interval); 88 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) 89 90 VNET_DEFINE_STATIC(struct ifnet *, nd6_defifp); 91 VNET_DEFINE(int, nd6_defifindex); 92 #define V_nd6_defifp VNET(nd6_defifp) 93 94 VNET_DEFINE(int, ip6_use_tempaddr) = 0; 95 96 VNET_DEFINE(int, ip6_desync_factor); 97 VNET_DEFINE(u_int32_t, ip6_temp_preferred_lifetime) = DEF_TEMP_PREFERRED_LIFETIME; 98 VNET_DEFINE(u_int32_t, ip6_temp_valid_lifetime) = DEF_TEMP_VALID_LIFETIME; 99 100 VNET_DEFINE(int, ip6_temp_regen_advance) = TEMPADDR_REGEN_ADVANCE; 101 102 #ifdef EXPERIMENTAL 103 VNET_DEFINE(int, nd6_ignore_ipv6_only_ra) = 1; 104 #endif 105 106 SYSCTL_DECL(_net_inet6_icmp6); 107 108 /* RTPREF_MEDIUM has to be 0! */ 109 #define RTPREF_HIGH 1 110 #define RTPREF_MEDIUM 0 111 #define RTPREF_LOW (-1) 112 #define RTPREF_RESERVED (-2) 113 #define RTPREF_INVALID (-3) /* internal */ 114 115 static void 116 defrouter_ref(struct nd_defrouter *dr) 117 { 118 119 refcount_acquire(&dr->refcnt); 120 } 121 122 void 123 defrouter_rele(struct nd_defrouter *dr) 124 { 125 126 if (refcount_release(&dr->refcnt)) 127 free(dr, M_IP6NDP); 128 } 129 130 /* 131 * Remove a router from the global list and optionally stash it in a 132 * caller-supplied queue. 133 */ 134 static void 135 defrouter_unlink(struct nd_defrouter *dr, struct nd6_drhead *drq) 136 { 137 138 ND6_WLOCK_ASSERT(); 139 140 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry); 141 V_nd6_list_genid++; 142 if (drq != NULL) 143 TAILQ_INSERT_TAIL(drq, dr, dr_entry); 144 } 145 146 /* 147 * Receive Router Solicitation Message - just for routers. 148 * Router solicitation/advertisement is mostly managed by userland program 149 * (rtadvd) so here we have no function like nd6_ra_output(). 150 * 151 * Based on RFC 2461 152 */ 153 void 154 nd6_rs_input(struct mbuf *m, int off, int icmp6len) 155 { 156 struct ifnet *ifp; 157 struct ip6_hdr *ip6; 158 struct nd_router_solicit *nd_rs; 159 struct in6_addr saddr6; 160 union nd_opts ndopts; 161 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 162 char *lladdr; 163 int lladdrlen; 164 165 ifp = m->m_pkthdr.rcvif; 166 167 /* 168 * Accept RS only when V_ip6_forwarding=1 and the interface has 169 * no ND6_IFF_ACCEPT_RTADV. 170 */ 171 if (!V_ip6_forwarding || ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) 172 goto freeit; 173 174 /* RFC 6980: Nodes MUST silently ignore fragments */ 175 if(m->m_flags & M_FRAGMENTED) 176 goto freeit; 177 178 /* Sanity checks */ 179 ip6 = mtod(m, struct ip6_hdr *); 180 if (ip6->ip6_hlim != 255) { 181 nd6log((LOG_ERR, 182 "%s: invalid hlim (%d) from %s to %s on %s\n", __func__, 183 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 184 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 185 goto bad; 186 } 187 188 /* 189 * Don't update the neighbor cache, if src = ::. 190 * This indicates that the src has no IP address assigned yet. 191 */ 192 saddr6 = ip6->ip6_src; 193 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 194 goto freeit; 195 196 if (m->m_len < off + icmp6len) { 197 m = m_pullup(m, off + icmp6len); 198 if (m == NULL) { 199 IP6STAT_INC(ip6s_exthdrtoolong); 200 return; 201 } 202 } 203 ip6 = mtod(m, struct ip6_hdr *); 204 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off); 205 206 icmp6len -= sizeof(*nd_rs); 207 nd6_option_init(nd_rs + 1, icmp6len, &ndopts); 208 if (nd6_options(&ndopts) < 0) { 209 nd6log((LOG_INFO, 210 "%s: invalid ND option, ignored\n", __func__)); 211 /* nd6_options have incremented stats */ 212 goto freeit; 213 } 214 215 lladdr = NULL; 216 lladdrlen = 0; 217 if (ndopts.nd_opts_src_lladdr) { 218 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 219 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 220 } 221 222 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 223 nd6log((LOG_INFO, 224 "%s: lladdrlen mismatch for %s (if %d, RS packet %d)\n", 225 __func__, ip6_sprintf(ip6bufs, &saddr6), 226 ifp->if_addrlen, lladdrlen - 2)); 227 goto bad; 228 } 229 230 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0); 231 232 freeit: 233 m_freem(m); 234 return; 235 236 bad: 237 ICMP6STAT_INC(icp6s_badrs); 238 m_freem(m); 239 } 240 241 #ifdef EXPERIMENTAL 242 /* 243 * An initial update routine for draft-ietf-6man-ipv6only-flag. 244 * We need to iterate over all default routers for the given 245 * interface to see whether they are all advertising the "S" 246 * (IPv6-Only) flag. If they do set, otherwise unset, the 247 * interface flag we later use to filter on. 248 */ 249 static void 250 defrtr_ipv6_only_ifp(struct ifnet *ifp) 251 { 252 struct nd_defrouter *dr; 253 bool ipv6_only, ipv6_only_old; 254 #ifdef INET 255 struct epoch_tracker et; 256 struct ifaddr *ifa; 257 bool has_ipv4_addr; 258 #endif 259 260 if (V_nd6_ignore_ipv6_only_ra != 0) 261 return; 262 263 ipv6_only = true; 264 ND6_RLOCK(); 265 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 266 if (dr->ifp == ifp && 267 (dr->raflags & ND_RA_FLAG_IPV6_ONLY) == 0) 268 ipv6_only = false; 269 ND6_RUNLOCK(); 270 271 IF_AFDATA_WLOCK(ifp); 272 ipv6_only_old = ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY; 273 IF_AFDATA_WUNLOCK(ifp); 274 275 /* If nothing changed, we have an early exit. */ 276 if (ipv6_only == ipv6_only_old) 277 return; 278 279 #ifdef INET 280 /* 281 * Should we want to set the IPV6-ONLY flag, check if the 282 * interface has a non-0/0 and non-link-local IPv4 address 283 * configured on it. If it has we will assume working 284 * IPv4 operations and will clear the interface flag. 285 */ 286 has_ipv4_addr = false; 287 if (ipv6_only) { 288 NET_EPOCH_ENTER(et); 289 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 290 if (ifa->ifa_addr->sa_family != AF_INET) 291 continue; 292 if (in_canforward( 293 satosin(ifa->ifa_addr)->sin_addr)) { 294 has_ipv4_addr = true; 295 break; 296 } 297 } 298 NET_EPOCH_EXIT(et); 299 } 300 if (ipv6_only && has_ipv4_addr) { 301 log(LOG_NOTICE, "%s rcvd RA w/ IPv6-Only flag set but has IPv4 " 302 "configured, ignoring IPv6-Only flag.\n", ifp->if_xname); 303 ipv6_only = false; 304 } 305 #endif 306 307 IF_AFDATA_WLOCK(ifp); 308 if (ipv6_only) 309 ND_IFINFO(ifp)->flags |= ND6_IFF_IPV6_ONLY; 310 else 311 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IPV6_ONLY; 312 IF_AFDATA_WUNLOCK(ifp); 313 314 #ifdef notyet 315 /* Send notification of flag change. */ 316 #endif 317 } 318 319 static void 320 defrtr_ipv6_only_ipf_down(struct ifnet *ifp) 321 { 322 323 IF_AFDATA_WLOCK(ifp); 324 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IPV6_ONLY; 325 IF_AFDATA_WUNLOCK(ifp); 326 } 327 #endif /* EXPERIMENTAL */ 328 329 void 330 nd6_ifnet_link_event(void *arg __unused, struct ifnet *ifp, int linkstate) 331 { 332 333 /* 334 * XXX-BZ we might want to trigger re-evaluation of our default router 335 * availability. E.g., on link down the default router might be 336 * unreachable but a different interface might still have connectivity. 337 */ 338 339 #ifdef EXPERIMENTAL 340 if (linkstate == LINK_STATE_DOWN) 341 defrtr_ipv6_only_ipf_down(ifp); 342 #endif 343 } 344 345 /* 346 * Receive Router Advertisement Message. 347 * 348 * Based on RFC 2461 349 * TODO: on-link bit on prefix information 350 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing 351 */ 352 void 353 nd6_ra_input(struct mbuf *m, int off, int icmp6len) 354 { 355 struct ifnet *ifp; 356 struct nd_ifinfo *ndi; 357 struct ip6_hdr *ip6; 358 struct nd_router_advert *nd_ra; 359 struct in6_addr saddr6; 360 struct nd_defrouter *dr; 361 union nd_opts ndopts; 362 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 363 int mcast; 364 365 /* 366 * We only accept RAs only when the per-interface flag 367 * ND6_IFF_ACCEPT_RTADV is on the receiving interface. 368 */ 369 ifp = m->m_pkthdr.rcvif; 370 ndi = ND_IFINFO(ifp); 371 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV)) 372 goto freeit; 373 374 /* RFC 6980: Nodes MUST silently ignore fragments */ 375 if(m->m_flags & M_FRAGMENTED) 376 goto freeit; 377 378 ip6 = mtod(m, struct ip6_hdr *); 379 if (ip6->ip6_hlim != 255) { 380 nd6log((LOG_ERR, 381 "%s: invalid hlim (%d) from %s to %s on %s\n", __func__, 382 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 383 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 384 goto bad; 385 } 386 387 saddr6 = ip6->ip6_src; 388 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 389 nd6log((LOG_ERR, 390 "%s: src %s is not link-local\n", __func__, 391 ip6_sprintf(ip6bufs, &saddr6))); 392 goto bad; 393 } 394 395 if (m->m_len < off + icmp6len) { 396 m = m_pullup(m, off + icmp6len); 397 if (m == NULL) { 398 IP6STAT_INC(ip6s_exthdrtoolong); 399 return; 400 } 401 } 402 ip6 = mtod(m, struct ip6_hdr *); 403 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off); 404 405 icmp6len -= sizeof(*nd_ra); 406 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 407 if (nd6_options(&ndopts) < 0) { 408 nd6log((LOG_INFO, 409 "%s: invalid ND option, ignored\n", __func__)); 410 /* nd6_options have incremented stats */ 411 goto freeit; 412 } 413 414 mcast = 0; 415 dr = NULL; 416 { 417 struct nd_defrouter dr0; 418 u_int32_t advreachable = nd_ra->nd_ra_reachable; 419 420 /* remember if this is a multicasted advertisement */ 421 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 422 mcast = 1; 423 424 bzero(&dr0, sizeof(dr0)); 425 dr0.rtaddr = saddr6; 426 dr0.raflags = nd_ra->nd_ra_flags_reserved; 427 /* 428 * Effectively-disable routes from RA messages when 429 * ND6_IFF_NO_RADR enabled on the receiving interface or 430 * (ip6.forwarding == 1 && ip6.rfc6204w3 != 1). 431 */ 432 if (ndi->flags & ND6_IFF_NO_RADR) 433 dr0.rtlifetime = 0; 434 else if (V_ip6_forwarding && !V_ip6_rfc6204w3) 435 dr0.rtlifetime = 0; 436 else 437 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 438 dr0.expire = time_uptime + dr0.rtlifetime; 439 dr0.ifp = ifp; 440 /* unspecified or not? (RFC 2461 6.3.4) */ 441 if (advreachable) { 442 advreachable = ntohl(advreachable); 443 if (advreachable <= MAX_REACHABLE_TIME && 444 ndi->basereachable != advreachable) { 445 ndi->basereachable = advreachable; 446 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 447 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */ 448 } 449 } 450 if (nd_ra->nd_ra_retransmit) 451 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 452 if (nd_ra->nd_ra_curhoplimit) { 453 if (ndi->chlim < nd_ra->nd_ra_curhoplimit) 454 ndi->chlim = nd_ra->nd_ra_curhoplimit; 455 else if (ndi->chlim != nd_ra->nd_ra_curhoplimit) { 456 log(LOG_ERR, "RA with a lower CurHopLimit sent from " 457 "%s on %s (current = %d, received = %d). " 458 "Ignored.\n", ip6_sprintf(ip6bufs, &ip6->ip6_src), 459 if_name(ifp), ndi->chlim, nd_ra->nd_ra_curhoplimit); 460 } 461 } 462 dr = defrtrlist_update(&dr0); 463 #ifdef EXPERIMENTAL 464 defrtr_ipv6_only_ifp(ifp); 465 #endif 466 } 467 468 /* 469 * prefix 470 */ 471 if (ndopts.nd_opts_pi) { 472 struct nd_opt_hdr *pt; 473 struct nd_opt_prefix_info *pi = NULL; 474 struct nd_prefixctl pr; 475 476 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 477 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 478 pt = (struct nd_opt_hdr *)((caddr_t)pt + 479 (pt->nd_opt_len << 3))) { 480 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 481 continue; 482 pi = (struct nd_opt_prefix_info *)pt; 483 484 if (pi->nd_opt_pi_len != 4) { 485 nd6log((LOG_INFO, 486 "%s: invalid option len %d for prefix " 487 "information option, ignored\n", __func__, 488 pi->nd_opt_pi_len)); 489 continue; 490 } 491 492 if (128 < pi->nd_opt_pi_prefix_len) { 493 nd6log((LOG_INFO, 494 "%s: invalid prefix len %d for prefix " 495 "information option, ignored\n", __func__, 496 pi->nd_opt_pi_prefix_len)); 497 continue; 498 } 499 500 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 501 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 502 nd6log((LOG_INFO, 503 "%s: invalid prefix %s, ignored\n", 504 __func__, ip6_sprintf(ip6bufs, 505 &pi->nd_opt_pi_prefix))); 506 continue; 507 } 508 509 bzero(&pr, sizeof(pr)); 510 pr.ndpr_prefix.sin6_family = AF_INET6; 511 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix); 512 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix; 513 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 514 515 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 516 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 517 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 518 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 519 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 520 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 521 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 522 (void)prelist_update(&pr, dr, m, mcast); 523 } 524 } 525 if (dr != NULL) { 526 defrouter_rele(dr); 527 dr = NULL; 528 } 529 530 /* 531 * MTU 532 */ 533 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 534 u_long mtu; 535 u_long maxmtu; 536 537 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 538 539 /* lower bound */ 540 if (mtu < IPV6_MMTU) { 541 nd6log((LOG_INFO, "%s: bogus mtu option mtu=%lu sent " 542 "from %s, ignoring\n", __func__, 543 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src))); 544 goto skip; 545 } 546 547 /* upper bound */ 548 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 549 ? ndi->maxmtu : ifp->if_mtu; 550 if (mtu <= maxmtu) { 551 int change = (ndi->linkmtu != mtu); 552 553 ndi->linkmtu = mtu; 554 if (change) { 555 /* in6_maxmtu may change */ 556 in6_setmaxmtu(); 557 rt_updatemtu(ifp); 558 } 559 } else { 560 nd6log((LOG_INFO, "%s: bogus mtu=%lu sent from %s; " 561 "exceeds maxmtu %lu, ignoring\n", __func__, 562 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu)); 563 } 564 } 565 566 skip: 567 568 /* 569 * Source link layer address 570 */ 571 { 572 char *lladdr = NULL; 573 int lladdrlen = 0; 574 575 if (ndopts.nd_opts_src_lladdr) { 576 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 577 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 578 } 579 580 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 581 nd6log((LOG_INFO, 582 "%s: lladdrlen mismatch for %s (if %d, RA packet %d)\n", 583 __func__, ip6_sprintf(ip6bufs, &saddr6), 584 ifp->if_addrlen, lladdrlen - 2)); 585 goto bad; 586 } 587 588 nd6_cache_lladdr(ifp, &saddr6, lladdr, 589 lladdrlen, ND_ROUTER_ADVERT, 0); 590 591 /* 592 * Installing a link-layer address might change the state of the 593 * router's neighbor cache, which might also affect our on-link 594 * detection of adveritsed prefixes. 595 */ 596 pfxlist_onlink_check(); 597 } 598 599 freeit: 600 m_freem(m); 601 return; 602 603 bad: 604 ICMP6STAT_INC(icp6s_badra); 605 m_freem(m); 606 } 607 608 /* PFXRTR */ 609 static struct nd_pfxrouter * 610 pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 611 { 612 struct nd_pfxrouter *search; 613 614 ND6_LOCK_ASSERT(); 615 616 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) { 617 if (search->router == dr) 618 break; 619 } 620 return (search); 621 } 622 623 static void 624 pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 625 { 626 struct nd_pfxrouter *new; 627 bool update; 628 629 ND6_UNLOCK_ASSERT(); 630 631 ND6_RLOCK(); 632 if (pfxrtr_lookup(pr, dr) != NULL) { 633 ND6_RUNLOCK(); 634 return; 635 } 636 ND6_RUNLOCK(); 637 638 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 639 if (new == NULL) 640 return; 641 defrouter_ref(dr); 642 new->router = dr; 643 644 ND6_WLOCK(); 645 if (pfxrtr_lookup(pr, dr) == NULL) { 646 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 647 update = true; 648 } else { 649 /* We lost a race to add the reference. */ 650 defrouter_rele(dr); 651 free(new, M_IP6NDP); 652 update = false; 653 } 654 ND6_WUNLOCK(); 655 656 if (update) 657 pfxlist_onlink_check(); 658 } 659 660 static void 661 pfxrtr_del(struct nd_pfxrouter *pfr) 662 { 663 664 ND6_WLOCK_ASSERT(); 665 666 LIST_REMOVE(pfr, pfr_entry); 667 defrouter_rele(pfr->router); 668 free(pfr, M_IP6NDP); 669 } 670 671 672 /* Default router list processing sub routines. */ 673 static void 674 defrouter_addreq(struct nd_defrouter *new) 675 { 676 struct sockaddr_in6 def, mask, gate; 677 struct rtentry *newrt = NULL; 678 unsigned int fibnum; 679 int error; 680 681 bzero(&def, sizeof(def)); 682 bzero(&mask, sizeof(mask)); 683 bzero(&gate, sizeof(gate)); 684 685 def.sin6_len = mask.sin6_len = gate.sin6_len = 686 sizeof(struct sockaddr_in6); 687 def.sin6_family = gate.sin6_family = AF_INET6; 688 gate.sin6_addr = new->rtaddr; 689 fibnum = new->ifp->if_fib; 690 691 error = in6_rtrequest(RTM_ADD, (struct sockaddr *)&def, 692 (struct sockaddr *)&gate, (struct sockaddr *)&mask, 693 RTF_GATEWAY, &newrt, fibnum); 694 if (newrt != NULL) 695 rt_routemsg(RTM_ADD, newrt, new->ifp, 0, fibnum); 696 if (error == 0) 697 new->installed = 1; 698 } 699 700 /* 701 * Remove the default route for a given router. 702 * This is just a subroutine function for defrouter_select_fib(), and 703 * should not be called from anywhere else. 704 */ 705 static void 706 defrouter_delreq(struct nd_defrouter *dr) 707 { 708 struct sockaddr_in6 def, mask, gate; 709 struct rtentry *oldrt = NULL; 710 struct epoch_tracker et; 711 unsigned int fibnum; 712 713 bzero(&def, sizeof(def)); 714 bzero(&mask, sizeof(mask)); 715 bzero(&gate, sizeof(gate)); 716 717 def.sin6_len = mask.sin6_len = gate.sin6_len = 718 sizeof(struct sockaddr_in6); 719 def.sin6_family = gate.sin6_family = AF_INET6; 720 gate.sin6_addr = dr->rtaddr; 721 fibnum = dr->ifp->if_fib; 722 723 NET_EPOCH_ENTER(et); 724 in6_rtrequest(RTM_DELETE, (struct sockaddr *)&def, 725 (struct sockaddr *)&gate, 726 (struct sockaddr *)&mask, RTF_GATEWAY, &oldrt, fibnum); 727 if (oldrt != NULL) 728 rt_routemsg(RTM_DELETE, oldrt, dr->ifp, 0, fibnum); 729 NET_EPOCH_EXIT(et); 730 731 dr->installed = 0; 732 } 733 734 static void 735 defrouter_del(struct nd_defrouter *dr) 736 { 737 struct nd_defrouter *deldr = NULL; 738 struct nd_prefix *pr; 739 struct nd_pfxrouter *pfxrtr; 740 741 ND6_UNLOCK_ASSERT(); 742 743 /* 744 * Flush all the routing table entries that use the router 745 * as a next hop. 746 */ 747 if (ND_IFINFO(dr->ifp)->flags & ND6_IFF_ACCEPT_RTADV) 748 rt6_flush(&dr->rtaddr, dr->ifp); 749 750 #ifdef EXPERIMENTAL 751 defrtr_ipv6_only_ifp(dr->ifp); 752 #endif 753 754 if (dr->installed) { 755 deldr = dr; 756 defrouter_delreq(dr); 757 } 758 759 /* 760 * Also delete all the pointers to the router in each prefix lists. 761 */ 762 ND6_WLOCK(); 763 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 764 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 765 pfxrtr_del(pfxrtr); 766 } 767 ND6_WUNLOCK(); 768 769 pfxlist_onlink_check(); 770 771 /* 772 * If the router is the primary one, choose a new one. 773 * Note that defrouter_select_fib() will remove the current 774 * gateway from the routing table. 775 */ 776 if (deldr) 777 defrouter_select_fib(deldr->ifp->if_fib); 778 779 /* 780 * Release the list reference. 781 */ 782 defrouter_rele(dr); 783 } 784 785 786 struct nd_defrouter * 787 defrouter_lookup_locked(const struct in6_addr *addr, struct ifnet *ifp) 788 { 789 struct nd_defrouter *dr; 790 791 ND6_LOCK_ASSERT(); 792 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 793 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) { 794 defrouter_ref(dr); 795 return (dr); 796 } 797 return (NULL); 798 } 799 800 struct nd_defrouter * 801 defrouter_lookup(const struct in6_addr *addr, struct ifnet *ifp) 802 { 803 struct nd_defrouter *dr; 804 805 ND6_RLOCK(); 806 dr = defrouter_lookup_locked(addr, ifp); 807 ND6_RUNLOCK(); 808 return (dr); 809 } 810 811 /* 812 * Remove all default routes from default router list. 813 */ 814 void 815 defrouter_reset(void) 816 { 817 struct nd_defrouter *dr, **dra; 818 int count, i; 819 820 count = i = 0; 821 822 /* 823 * We can't delete routes with the ND lock held, so make a copy of the 824 * current default router list and use that when deleting routes. 825 */ 826 ND6_RLOCK(); 827 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 828 count++; 829 ND6_RUNLOCK(); 830 831 dra = malloc(count * sizeof(*dra), M_TEMP, M_WAITOK | M_ZERO); 832 833 ND6_RLOCK(); 834 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 835 if (i == count) 836 break; 837 defrouter_ref(dr); 838 dra[i++] = dr; 839 } 840 ND6_RUNLOCK(); 841 842 for (i = 0; i < count && dra[i] != NULL; i++) { 843 defrouter_delreq(dra[i]); 844 defrouter_rele(dra[i]); 845 } 846 free(dra, M_TEMP); 847 848 /* 849 * XXX should we also nuke any default routers in the kernel, by 850 * going through them by rtalloc1()? 851 */ 852 } 853 854 /* 855 * Look up a matching default router list entry and remove it. Returns true if a 856 * matching entry was found, false otherwise. 857 */ 858 bool 859 defrouter_remove(struct in6_addr *addr, struct ifnet *ifp) 860 { 861 struct nd_defrouter *dr; 862 863 ND6_WLOCK(); 864 dr = defrouter_lookup_locked(addr, ifp); 865 if (dr == NULL) { 866 ND6_WUNLOCK(); 867 return (false); 868 } 869 870 defrouter_unlink(dr, NULL); 871 ND6_WUNLOCK(); 872 defrouter_del(dr); 873 defrouter_rele(dr); 874 return (true); 875 } 876 877 /* 878 * for default router selection 879 * regards router-preference field as a 2-bit signed integer 880 */ 881 static int 882 rtpref(struct nd_defrouter *dr) 883 { 884 switch (dr->raflags & ND_RA_FLAG_RTPREF_MASK) { 885 case ND_RA_FLAG_RTPREF_HIGH: 886 return (RTPREF_HIGH); 887 case ND_RA_FLAG_RTPREF_MEDIUM: 888 case ND_RA_FLAG_RTPREF_RSV: 889 return (RTPREF_MEDIUM); 890 case ND_RA_FLAG_RTPREF_LOW: 891 return (RTPREF_LOW); 892 default: 893 /* 894 * This case should never happen. If it did, it would mean a 895 * serious bug of kernel internal. We thus always bark here. 896 * Or, can we even panic? 897 */ 898 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->raflags); 899 return (RTPREF_INVALID); 900 } 901 /* NOTREACHED */ 902 } 903 904 /* 905 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 906 * draft-ietf-ipngwg-router-selection: 907 * 1) Routers that are reachable or probably reachable should be preferred. 908 * If we have more than one (probably) reachable router, prefer ones 909 * with the highest router preference. 910 * 2) When no routers on the list are known to be reachable or 911 * probably reachable, routers SHOULD be selected in a round-robin 912 * fashion, regardless of router preference values. 913 * 3) If the Default Router List is empty, assume that all 914 * destinations are on-link. 915 * 916 * We assume nd_defrouter is sorted by router preference value. 917 * Since the code below covers both with and without router preference cases, 918 * we do not need to classify the cases by ifdef. 919 * 920 * At this moment, we do not try to install more than one default router, 921 * even when the multipath routing is available, because we're not sure about 922 * the benefits for stub hosts comparing to the risk of making the code 923 * complicated and the possibility of introducing bugs. 924 * 925 * We maintain a single list of routers for multiple FIBs, only considering one 926 * at a time based on the receiving interface's FIB. If @fibnum is RT_ALL_FIBS, 927 * we do the whole thing multiple times. 928 */ 929 void 930 defrouter_select_fib(int fibnum) 931 { 932 struct epoch_tracker et; 933 struct nd_defrouter *dr, *selected_dr, *installed_dr; 934 struct llentry *ln = NULL; 935 936 if (fibnum == RT_ALL_FIBS) { 937 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) { 938 defrouter_select_fib(fibnum); 939 } 940 } 941 942 ND6_RLOCK(); 943 /* 944 * Let's handle easy case (3) first: 945 * If default router list is empty, there's nothing to be done. 946 */ 947 if (TAILQ_EMPTY(&V_nd6_defrouter)) { 948 ND6_RUNLOCK(); 949 return; 950 } 951 952 /* 953 * Search for a (probably) reachable router from the list. 954 * We just pick up the first reachable one (if any), assuming that 955 * the ordering rule of the list described in defrtrlist_update(). 956 */ 957 selected_dr = installed_dr = NULL; 958 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 959 NET_EPOCH_ENTER(et); 960 if (selected_dr == NULL && dr->ifp->if_fib == fibnum && 961 (ln = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) && 962 ND6_IS_LLINFO_PROBREACH(ln)) { 963 selected_dr = dr; 964 defrouter_ref(selected_dr); 965 } 966 NET_EPOCH_EXIT(et); 967 if (ln != NULL) { 968 LLE_RUNLOCK(ln); 969 ln = NULL; 970 } 971 972 if (dr->installed && dr->ifp->if_fib == fibnum) { 973 if (installed_dr == NULL) { 974 installed_dr = dr; 975 defrouter_ref(installed_dr); 976 } else { 977 /* 978 * this should not happen. 979 * warn for diagnosis. 980 */ 981 log(LOG_ERR, "defrouter_select_fib: more than " 982 "one router is installed\n"); 983 } 984 } 985 } 986 /* 987 * If none of the default routers was found to be reachable, 988 * round-robin the list regardless of preference. 989 * Otherwise, if we have an installed router, check if the selected 990 * (reachable) router should really be preferred to the installed one. 991 * We only prefer the new router when the old one is not reachable 992 * or when the new one has a really higher preference value. 993 */ 994 if (selected_dr == NULL) { 995 if (installed_dr == NULL || 996 TAILQ_NEXT(installed_dr, dr_entry) == NULL) 997 dr = TAILQ_FIRST(&V_nd6_defrouter); 998 else 999 dr = TAILQ_NEXT(installed_dr, dr_entry); 1000 1001 /* Ensure we select a router for this FIB. */ 1002 TAILQ_FOREACH_FROM(dr, &V_nd6_defrouter, dr_entry) { 1003 if (dr->ifp->if_fib == fibnum) { 1004 selected_dr = dr; 1005 defrouter_ref(selected_dr); 1006 break; 1007 } 1008 } 1009 } else if (installed_dr != NULL) { 1010 NET_EPOCH_ENTER(et); 1011 if ((ln = nd6_lookup(&installed_dr->rtaddr, 0, 1012 installed_dr->ifp)) && 1013 ND6_IS_LLINFO_PROBREACH(ln) && 1014 installed_dr->ifp->if_fib == fibnum && 1015 rtpref(selected_dr) <= rtpref(installed_dr)) { 1016 defrouter_rele(selected_dr); 1017 selected_dr = installed_dr; 1018 } 1019 NET_EPOCH_EXIT(et); 1020 if (ln != NULL) 1021 LLE_RUNLOCK(ln); 1022 } 1023 ND6_RUNLOCK(); 1024 1025 NET_EPOCH_ENTER(et); 1026 /* 1027 * If we selected a router for this FIB and it's different 1028 * than the installed one, remove the installed router and 1029 * install the selected one in its place. 1030 */ 1031 if (installed_dr != selected_dr) { 1032 if (installed_dr != NULL) { 1033 defrouter_delreq(installed_dr); 1034 defrouter_rele(installed_dr); 1035 } 1036 if (selected_dr != NULL) 1037 defrouter_addreq(selected_dr); 1038 } 1039 if (selected_dr != NULL) 1040 defrouter_rele(selected_dr); 1041 NET_EPOCH_EXIT(et); 1042 } 1043 1044 static struct nd_defrouter * 1045 defrtrlist_update(struct nd_defrouter *new) 1046 { 1047 struct nd_defrouter *dr, *n; 1048 uint64_t genid; 1049 int oldpref; 1050 bool writelocked; 1051 1052 if (new->rtlifetime == 0) { 1053 defrouter_remove(&new->rtaddr, new->ifp); 1054 return (NULL); 1055 } 1056 1057 ND6_RLOCK(); 1058 writelocked = false; 1059 restart: 1060 dr = defrouter_lookup_locked(&new->rtaddr, new->ifp); 1061 if (dr != NULL) { 1062 oldpref = rtpref(dr); 1063 1064 /* override */ 1065 dr->raflags = new->raflags; /* XXX flag check */ 1066 dr->rtlifetime = new->rtlifetime; 1067 dr->expire = new->expire; 1068 1069 /* 1070 * If the preference does not change, there's no need 1071 * to sort the entries. Also make sure the selected 1072 * router is still installed in the kernel. 1073 */ 1074 if (dr->installed && rtpref(new) == oldpref) { 1075 if (writelocked) 1076 ND6_WUNLOCK(); 1077 else 1078 ND6_RUNLOCK(); 1079 return (dr); 1080 } 1081 } 1082 1083 /* 1084 * The router needs to be reinserted into the default router 1085 * list, so upgrade to a write lock. If that fails and the list 1086 * has potentially changed while the lock was dropped, we'll 1087 * redo the lookup with the write lock held. 1088 */ 1089 if (!writelocked) { 1090 writelocked = true; 1091 if (!ND6_TRY_UPGRADE()) { 1092 genid = V_nd6_list_genid; 1093 ND6_RUNLOCK(); 1094 ND6_WLOCK(); 1095 if (genid != V_nd6_list_genid) 1096 goto restart; 1097 } 1098 } 1099 1100 if (dr != NULL) { 1101 /* 1102 * The preferred router may have changed, so relocate this 1103 * router. 1104 */ 1105 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry); 1106 n = dr; 1107 } else { 1108 n = malloc(sizeof(*n), M_IP6NDP, M_NOWAIT | M_ZERO); 1109 if (n == NULL) { 1110 ND6_WUNLOCK(); 1111 return (NULL); 1112 } 1113 memcpy(n, new, sizeof(*n)); 1114 /* Initialize with an extra reference for the caller. */ 1115 refcount_init(&n->refcnt, 2); 1116 } 1117 1118 /* 1119 * Insert the new router in the Default Router List; 1120 * The Default Router List should be in the descending order 1121 * of router-preferece. Routers with the same preference are 1122 * sorted in the arriving time order. 1123 */ 1124 1125 /* insert at the end of the group */ 1126 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 1127 if (rtpref(n) > rtpref(dr)) 1128 break; 1129 } 1130 if (dr != NULL) 1131 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 1132 else 1133 TAILQ_INSERT_TAIL(&V_nd6_defrouter, n, dr_entry); 1134 V_nd6_list_genid++; 1135 ND6_WUNLOCK(); 1136 1137 defrouter_select_fib(new->ifp->if_fib); 1138 1139 return (n); 1140 } 1141 1142 static int 1143 in6_init_prefix_ltimes(struct nd_prefix *ndpr) 1144 { 1145 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 1146 ndpr->ndpr_preferred = 0; 1147 else 1148 ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime; 1149 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1150 ndpr->ndpr_expire = 0; 1151 else 1152 ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime; 1153 1154 return 0; 1155 } 1156 1157 static void 1158 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6) 1159 { 1160 /* init ia6t_expire */ 1161 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 1162 lt6->ia6t_expire = 0; 1163 else { 1164 lt6->ia6t_expire = time_uptime; 1165 lt6->ia6t_expire += lt6->ia6t_vltime; 1166 } 1167 1168 /* init ia6t_preferred */ 1169 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 1170 lt6->ia6t_preferred = 0; 1171 else { 1172 lt6->ia6t_preferred = time_uptime; 1173 lt6->ia6t_preferred += lt6->ia6t_pltime; 1174 } 1175 } 1176 1177 static struct in6_ifaddr * 1178 in6_ifadd(struct nd_prefixctl *pr, int mcast) 1179 { 1180 struct ifnet *ifp = pr->ndpr_ifp; 1181 struct ifaddr *ifa; 1182 struct in6_aliasreq ifra; 1183 struct in6_ifaddr *ia, *ib; 1184 int error, plen0; 1185 struct in6_addr mask; 1186 int prefixlen = pr->ndpr_plen; 1187 int updateflags; 1188 char ip6buf[INET6_ADDRSTRLEN]; 1189 1190 in6_prefixlen2mask(&mask, prefixlen); 1191 1192 /* 1193 * find a link-local address (will be interface ID). 1194 * Is it really mandatory? Theoretically, a global or a site-local 1195 * address can be configured without a link-local address, if we 1196 * have a unique interface identifier... 1197 * 1198 * it is not mandatory to have a link-local address, we can generate 1199 * interface identifier on the fly. we do this because: 1200 * (1) it should be the easiest way to find interface identifier. 1201 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1202 * for multiple addresses on a single interface, and possible shortcut 1203 * of DAD. we omitted DAD for this reason in the past. 1204 * (3) a user can prevent autoconfiguration of global address 1205 * by removing link-local address by hand (this is partly because we 1206 * don't have other way to control the use of IPv6 on an interface. 1207 * this has been our design choice - cf. NRL's "ifconfig auto"). 1208 * (4) it is easier to manage when an interface has addresses 1209 * with the same interface identifier, than to have multiple addresses 1210 * with different interface identifiers. 1211 */ 1212 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1213 if (ifa) 1214 ib = (struct in6_ifaddr *)ifa; 1215 else 1216 return NULL; 1217 1218 /* prefixlen + ifidlen must be equal to 128 */ 1219 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1220 if (prefixlen != plen0) { 1221 ifa_free(ifa); 1222 nd6log((LOG_INFO, 1223 "%s: wrong prefixlen for %s (prefix=%d ifid=%d)\n", 1224 __func__, if_name(ifp), prefixlen, 128 - plen0)); 1225 return NULL; 1226 } 1227 1228 /* make ifaddr */ 1229 in6_prepare_ifra(&ifra, &pr->ndpr_prefix.sin6_addr, &mask); 1230 1231 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, &mask); 1232 /* interface ID */ 1233 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1234 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1235 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1236 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1237 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1238 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1239 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1240 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1241 ifa_free(ifa); 1242 1243 /* lifetimes. */ 1244 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1245 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1246 1247 /* XXX: scope zone ID? */ 1248 1249 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1250 1251 /* 1252 * Make sure that we do not have this address already. This should 1253 * usually not happen, but we can still see this case, e.g., if we 1254 * have manually configured the exact address to be configured. 1255 */ 1256 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 1257 &ifra.ifra_addr.sin6_addr); 1258 if (ifa != NULL) { 1259 ifa_free(ifa); 1260 /* this should be rare enough to make an explicit log */ 1261 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1262 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr)); 1263 return (NULL); 1264 } 1265 1266 /* 1267 * Allocate ifaddr structure, link into chain, etc. 1268 * If we are going to create a new address upon receiving a multicasted 1269 * RA, we need to impose a random delay before starting DAD. 1270 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1271 */ 1272 updateflags = 0; 1273 if (mcast) 1274 updateflags |= IN6_IFAUPDATE_DADDELAY; 1275 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 1276 nd6log((LOG_ERR, 1277 "%s: failed to make ifaddr %s on %s (errno=%d)\n", __func__, 1278 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr), 1279 if_name(ifp), error)); 1280 return (NULL); /* ifaddr must not have been allocated. */ 1281 } 1282 1283 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1284 /* 1285 * XXXRW: Assumption of non-NULLness here might not be true with 1286 * fine-grained locking -- should we validate it? Or just return 1287 * earlier ifa rather than looking it up again? 1288 */ 1289 return (ia); /* this is always non-NULL and referenced. */ 1290 } 1291 1292 static struct nd_prefix * 1293 nd6_prefix_lookup_locked(struct nd_prefixctl *key) 1294 { 1295 struct nd_prefix *search; 1296 1297 ND6_LOCK_ASSERT(); 1298 1299 LIST_FOREACH(search, &V_nd_prefix, ndpr_entry) { 1300 if (key->ndpr_ifp == search->ndpr_ifp && 1301 key->ndpr_plen == search->ndpr_plen && 1302 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 1303 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 1304 nd6_prefix_ref(search); 1305 break; 1306 } 1307 } 1308 return (search); 1309 } 1310 1311 struct nd_prefix * 1312 nd6_prefix_lookup(struct nd_prefixctl *key) 1313 { 1314 struct nd_prefix *search; 1315 1316 ND6_RLOCK(); 1317 search = nd6_prefix_lookup_locked(key); 1318 ND6_RUNLOCK(); 1319 return (search); 1320 } 1321 1322 void 1323 nd6_prefix_ref(struct nd_prefix *pr) 1324 { 1325 1326 refcount_acquire(&pr->ndpr_refcnt); 1327 } 1328 1329 void 1330 nd6_prefix_rele(struct nd_prefix *pr) 1331 { 1332 1333 if (refcount_release(&pr->ndpr_refcnt)) { 1334 KASSERT(LIST_EMPTY(&pr->ndpr_advrtrs), 1335 ("prefix %p has advertising routers", pr)); 1336 free(pr, M_IP6NDP); 1337 } 1338 } 1339 1340 int 1341 nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 1342 struct nd_prefix **newp) 1343 { 1344 struct nd_prefix *new; 1345 char ip6buf[INET6_ADDRSTRLEN]; 1346 int error; 1347 1348 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 1349 if (new == NULL) 1350 return (ENOMEM); 1351 refcount_init(&new->ndpr_refcnt, newp != NULL ? 2 : 1); 1352 new->ndpr_ifp = pr->ndpr_ifp; 1353 new->ndpr_prefix = pr->ndpr_prefix; 1354 new->ndpr_plen = pr->ndpr_plen; 1355 new->ndpr_vltime = pr->ndpr_vltime; 1356 new->ndpr_pltime = pr->ndpr_pltime; 1357 new->ndpr_flags = pr->ndpr_flags; 1358 if ((error = in6_init_prefix_ltimes(new)) != 0) { 1359 free(new, M_IP6NDP); 1360 return (error); 1361 } 1362 new->ndpr_lastupdate = time_uptime; 1363 1364 /* initialization */ 1365 LIST_INIT(&new->ndpr_advrtrs); 1366 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 1367 /* make prefix in the canonical form */ 1368 IN6_MASK_ADDR(&new->ndpr_prefix.sin6_addr, &new->ndpr_mask); 1369 1370 ND6_WLOCK(); 1371 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry); 1372 V_nd6_list_genid++; 1373 ND6_WUNLOCK(); 1374 1375 /* ND_OPT_PI_FLAG_ONLINK processing */ 1376 if (new->ndpr_raf_onlink) { 1377 struct epoch_tracker et; 1378 1379 ND6_ONLINK_LOCK(); 1380 NET_EPOCH_ENTER(et); 1381 if ((error = nd6_prefix_onlink(new)) != 0) { 1382 nd6log((LOG_ERR, "%s: failed to make the prefix %s/%d " 1383 "on-link on %s (errno=%d)\n", __func__, 1384 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1385 pr->ndpr_plen, if_name(pr->ndpr_ifp), error)); 1386 /* proceed anyway. XXX: is it correct? */ 1387 } 1388 NET_EPOCH_EXIT(et); 1389 ND6_ONLINK_UNLOCK(); 1390 } 1391 1392 if (dr != NULL) 1393 pfxrtr_add(new, dr); 1394 if (newp != NULL) 1395 *newp = new; 1396 return (0); 1397 } 1398 1399 /* 1400 * Remove a prefix from the prefix list and optionally stash it in a 1401 * caller-provided list. 1402 * 1403 * The ND6 lock must be held. 1404 */ 1405 void 1406 nd6_prefix_unlink(struct nd_prefix *pr, struct nd_prhead *list) 1407 { 1408 1409 ND6_WLOCK_ASSERT(); 1410 1411 LIST_REMOVE(pr, ndpr_entry); 1412 V_nd6_list_genid++; 1413 if (list != NULL) 1414 LIST_INSERT_HEAD(list, pr, ndpr_entry); 1415 } 1416 1417 /* 1418 * Free an unlinked prefix, first marking it off-link if necessary. 1419 */ 1420 void 1421 nd6_prefix_del(struct nd_prefix *pr) 1422 { 1423 struct nd_pfxrouter *pfr, *next; 1424 int e; 1425 char ip6buf[INET6_ADDRSTRLEN]; 1426 1427 KASSERT(pr->ndpr_addrcnt == 0, 1428 ("prefix %p has referencing addresses", pr)); 1429 ND6_UNLOCK_ASSERT(); 1430 1431 /* 1432 * Though these flags are now meaningless, we'd rather keep the value 1433 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users 1434 * when executing "ndp -p". 1435 */ 1436 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1437 ND6_ONLINK_LOCK(); 1438 if ((e = nd6_prefix_offlink(pr)) != 0) { 1439 nd6log((LOG_ERR, 1440 "%s: failed to make the prefix %s/%d offlink on %s " 1441 "(errno=%d)\n", __func__, 1442 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1443 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1444 /* what should we do? */ 1445 } 1446 ND6_ONLINK_UNLOCK(); 1447 } 1448 1449 /* Release references to routers that have advertised this prefix. */ 1450 ND6_WLOCK(); 1451 LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next) 1452 pfxrtr_del(pfr); 1453 ND6_WUNLOCK(); 1454 1455 nd6_prefix_rele(pr); 1456 1457 pfxlist_onlink_check(); 1458 } 1459 1460 static int 1461 prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr, 1462 struct mbuf *m, int mcast) 1463 { 1464 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 1465 struct ifaddr *ifa; 1466 struct ifnet *ifp = new->ndpr_ifp; 1467 struct nd_prefix *pr; 1468 int error = 0; 1469 int auth; 1470 struct in6_addrlifetime lt6_tmp; 1471 char ip6buf[INET6_ADDRSTRLEN]; 1472 1473 NET_EPOCH_ASSERT(); 1474 1475 auth = 0; 1476 if (m) { 1477 /* 1478 * Authenticity for NA consists authentication for 1479 * both IP header and IP datagrams, doesn't it ? 1480 */ 1481 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1482 auth = ((m->m_flags & M_AUTHIPHDR) && 1483 (m->m_flags & M_AUTHIPDGM)); 1484 #endif 1485 } 1486 1487 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1488 /* 1489 * nd6_prefix_lookup() ensures that pr and new have the same 1490 * prefix on a same interface. 1491 */ 1492 1493 /* 1494 * Update prefix information. Note that the on-link (L) bit 1495 * and the autonomous (A) bit should NOT be changed from 1 1496 * to 0. 1497 */ 1498 if (new->ndpr_raf_onlink == 1) 1499 pr->ndpr_raf_onlink = 1; 1500 if (new->ndpr_raf_auto == 1) 1501 pr->ndpr_raf_auto = 1; 1502 if (new->ndpr_raf_onlink) { 1503 pr->ndpr_vltime = new->ndpr_vltime; 1504 pr->ndpr_pltime = new->ndpr_pltime; 1505 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1506 pr->ndpr_lastupdate = time_uptime; 1507 } 1508 1509 if (new->ndpr_raf_onlink && 1510 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1511 ND6_ONLINK_LOCK(); 1512 if ((error = nd6_prefix_onlink(pr)) != 0) { 1513 nd6log((LOG_ERR, 1514 "%s: failed to make the prefix %s/%d " 1515 "on-link on %s (errno=%d)\n", __func__, 1516 ip6_sprintf(ip6buf, 1517 &pr->ndpr_prefix.sin6_addr), 1518 pr->ndpr_plen, if_name(pr->ndpr_ifp), 1519 error)); 1520 /* proceed anyway. XXX: is it correct? */ 1521 } 1522 ND6_ONLINK_UNLOCK(); 1523 } 1524 1525 if (dr != NULL) 1526 pfxrtr_add(pr, dr); 1527 } else { 1528 if (new->ndpr_vltime == 0) 1529 goto end; 1530 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1531 goto end; 1532 1533 error = nd6_prelist_add(new, dr, &pr); 1534 if (error != 0) { 1535 nd6log((LOG_NOTICE, "%s: nd6_prelist_add() failed for " 1536 "the prefix %s/%d on %s (errno=%d)\n", __func__, 1537 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr), 1538 new->ndpr_plen, if_name(new->ndpr_ifp), error)); 1539 goto end; /* we should just give up in this case. */ 1540 } 1541 1542 /* 1543 * XXX: from the ND point of view, we can ignore a prefix 1544 * with the on-link bit being zero. However, we need a 1545 * prefix structure for references from autoconfigured 1546 * addresses. Thus, we explicitly make sure that the prefix 1547 * itself expires now. 1548 */ 1549 if (pr->ndpr_raf_onlink == 0) { 1550 pr->ndpr_vltime = 0; 1551 pr->ndpr_pltime = 0; 1552 in6_init_prefix_ltimes(pr); 1553 } 1554 } 1555 1556 /* 1557 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1558 * Note that pr must be non NULL at this point. 1559 */ 1560 1561 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1562 if (!new->ndpr_raf_auto) 1563 goto end; 1564 1565 /* 1566 * 5.5.3 (b). the link-local prefix should have been ignored in 1567 * nd6_ra_input. 1568 */ 1569 1570 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1571 if (new->ndpr_pltime > new->ndpr_vltime) { 1572 error = EINVAL; /* XXX: won't be used */ 1573 goto end; 1574 } 1575 1576 /* 1577 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1578 * an address configured by stateless autoconfiguration already in the 1579 * list of addresses associated with the interface, and the Valid 1580 * Lifetime is not 0, form an address. We first check if we have 1581 * a matching prefix. 1582 * Note: we apply a clarification in rfc2462bis-02 here. We only 1583 * consider autoconfigured addresses while RFC2462 simply said 1584 * "address". 1585 */ 1586 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1587 struct in6_ifaddr *ifa6; 1588 u_int32_t remaininglifetime; 1589 1590 if (ifa->ifa_addr->sa_family != AF_INET6) 1591 continue; 1592 1593 ifa6 = (struct in6_ifaddr *)ifa; 1594 1595 /* 1596 * We only consider autoconfigured addresses as per rfc2462bis. 1597 */ 1598 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1599 continue; 1600 1601 /* 1602 * Spec is not clear here, but I believe we should concentrate 1603 * on unicast (i.e. not anycast) addresses. 1604 * XXX: other ia6_flags? detached or duplicated? 1605 */ 1606 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1607 continue; 1608 1609 /* 1610 * Ignore the address if it is not associated with a prefix 1611 * or is associated with a prefix that is different from this 1612 * one. (pr is never NULL here) 1613 */ 1614 if (ifa6->ia6_ndpr != pr) 1615 continue; 1616 1617 if (ia6_match == NULL) /* remember the first one */ 1618 ia6_match = ifa6; 1619 1620 /* 1621 * An already autoconfigured address matched. Now that we 1622 * are sure there is at least one matched address, we can 1623 * proceed to 5.5.3. (e): update the lifetimes according to the 1624 * "two hours" rule and the privacy extension. 1625 * We apply some clarifications in rfc2462bis: 1626 * - use remaininglifetime instead of storedlifetime as a 1627 * variable name 1628 * - remove the dead code in the "two-hour" rule 1629 */ 1630 #define TWOHOUR (120*60) 1631 lt6_tmp = ifa6->ia6_lifetime; 1632 1633 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1634 remaininglifetime = ND6_INFINITE_LIFETIME; 1635 else if (time_uptime - ifa6->ia6_updatetime > 1636 lt6_tmp.ia6t_vltime) { 1637 /* 1638 * The case of "invalid" address. We should usually 1639 * not see this case. 1640 */ 1641 remaininglifetime = 0; 1642 } else 1643 remaininglifetime = lt6_tmp.ia6t_vltime - 1644 (time_uptime - ifa6->ia6_updatetime); 1645 1646 /* when not updating, keep the current stored lifetime. */ 1647 lt6_tmp.ia6t_vltime = remaininglifetime; 1648 1649 if (TWOHOUR < new->ndpr_vltime || 1650 remaininglifetime < new->ndpr_vltime) { 1651 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1652 } else if (remaininglifetime <= TWOHOUR) { 1653 if (auth) { 1654 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1655 } 1656 } else { 1657 /* 1658 * new->ndpr_vltime <= TWOHOUR && 1659 * TWOHOUR < remaininglifetime 1660 */ 1661 lt6_tmp.ia6t_vltime = TWOHOUR; 1662 } 1663 1664 /* The 2 hour rule is not imposed for preferred lifetime. */ 1665 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1666 1667 in6_init_address_ltimes(pr, <6_tmp); 1668 1669 /* 1670 * We need to treat lifetimes for temporary addresses 1671 * differently, according to 1672 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1673 * we only update the lifetimes when they are in the maximum 1674 * intervals. 1675 */ 1676 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1677 u_int32_t maxvltime, maxpltime; 1678 1679 if (V_ip6_temp_valid_lifetime > 1680 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1681 V_ip6_desync_factor)) { 1682 maxvltime = V_ip6_temp_valid_lifetime - 1683 (time_uptime - ifa6->ia6_createtime) - 1684 V_ip6_desync_factor; 1685 } else 1686 maxvltime = 0; 1687 if (V_ip6_temp_preferred_lifetime > 1688 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1689 V_ip6_desync_factor)) { 1690 maxpltime = V_ip6_temp_preferred_lifetime - 1691 (time_uptime - ifa6->ia6_createtime) - 1692 V_ip6_desync_factor; 1693 } else 1694 maxpltime = 0; 1695 1696 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1697 lt6_tmp.ia6t_vltime > maxvltime) { 1698 lt6_tmp.ia6t_vltime = maxvltime; 1699 } 1700 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1701 lt6_tmp.ia6t_pltime > maxpltime) { 1702 lt6_tmp.ia6t_pltime = maxpltime; 1703 } 1704 } 1705 ifa6->ia6_lifetime = lt6_tmp; 1706 ifa6->ia6_updatetime = time_uptime; 1707 } 1708 if (ia6_match == NULL && new->ndpr_vltime) { 1709 int ifidlen; 1710 1711 /* 1712 * 5.5.3 (d) (continued) 1713 * No address matched and the valid lifetime is non-zero. 1714 * Create a new address. 1715 */ 1716 1717 /* 1718 * Prefix Length check: 1719 * If the sum of the prefix length and interface identifier 1720 * length does not equal 128 bits, the Prefix Information 1721 * option MUST be ignored. The length of the interface 1722 * identifier is defined in a separate link-type specific 1723 * document. 1724 */ 1725 ifidlen = in6_if2idlen(ifp); 1726 if (ifidlen < 0) { 1727 /* this should not happen, so we always log it. */ 1728 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1729 if_name(ifp)); 1730 goto end; 1731 } 1732 if (ifidlen + pr->ndpr_plen != 128) { 1733 nd6log((LOG_INFO, 1734 "%s: invalid prefixlen %d for %s, ignored\n", 1735 __func__, pr->ndpr_plen, if_name(ifp))); 1736 goto end; 1737 } 1738 1739 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1740 /* 1741 * note that we should use pr (not new) for reference. 1742 */ 1743 pr->ndpr_addrcnt++; 1744 ia6->ia6_ndpr = pr; 1745 1746 /* 1747 * RFC 3041 3.3 (2). 1748 * When a new public address is created as described 1749 * in RFC2462, also create a new temporary address. 1750 * 1751 * RFC 3041 3.5. 1752 * When an interface connects to a new link, a new 1753 * randomized interface identifier should be generated 1754 * immediately together with a new set of temporary 1755 * addresses. Thus, we specifiy 1 as the 2nd arg of 1756 * in6_tmpifadd(). 1757 */ 1758 if (V_ip6_use_tempaddr) { 1759 int e; 1760 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1761 nd6log((LOG_NOTICE, "%s: failed to " 1762 "create a temporary address " 1763 "(errno=%d)\n", __func__, e)); 1764 } 1765 } 1766 ifa_free(&ia6->ia_ifa); 1767 1768 /* 1769 * A newly added address might affect the status 1770 * of other addresses, so we check and update it. 1771 * XXX: what if address duplication happens? 1772 */ 1773 pfxlist_onlink_check(); 1774 } else { 1775 /* just set an error. do not bark here. */ 1776 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1777 } 1778 } 1779 1780 end: 1781 if (pr != NULL) 1782 nd6_prefix_rele(pr); 1783 return (error); 1784 } 1785 1786 /* 1787 * A supplement function used in the on-link detection below; 1788 * detect if a given prefix has a (probably) reachable advertising router. 1789 * XXX: lengthy function name... 1790 */ 1791 static struct nd_pfxrouter * 1792 find_pfxlist_reachable_router(struct nd_prefix *pr) 1793 { 1794 struct epoch_tracker et; 1795 struct nd_pfxrouter *pfxrtr; 1796 struct llentry *ln; 1797 int canreach; 1798 1799 ND6_LOCK_ASSERT(); 1800 1801 NET_EPOCH_ENTER(et); 1802 LIST_FOREACH(pfxrtr, &pr->ndpr_advrtrs, pfr_entry) { 1803 ln = nd6_lookup(&pfxrtr->router->rtaddr, 0, pfxrtr->router->ifp); 1804 if (ln == NULL) 1805 continue; 1806 canreach = ND6_IS_LLINFO_PROBREACH(ln); 1807 LLE_RUNLOCK(ln); 1808 if (canreach) 1809 break; 1810 } 1811 NET_EPOCH_EXIT(et); 1812 return (pfxrtr); 1813 } 1814 1815 /* 1816 * Check if each prefix in the prefix list has at least one available router 1817 * that advertised the prefix (a router is "available" if its neighbor cache 1818 * entry is reachable or probably reachable). 1819 * If the check fails, the prefix may be off-link, because, for example, 1820 * we have moved from the network but the lifetime of the prefix has not 1821 * expired yet. So we should not use the prefix if there is another prefix 1822 * that has an available router. 1823 * But, if there is no prefix that has an available router, we still regard 1824 * all the prefixes as on-link. This is because we can't tell if all the 1825 * routers are simply dead or if we really moved from the network and there 1826 * is no router around us. 1827 */ 1828 void 1829 pfxlist_onlink_check(void) 1830 { 1831 struct nd_prefix *pr; 1832 struct in6_ifaddr *ifa; 1833 struct nd_defrouter *dr; 1834 struct nd_pfxrouter *pfxrtr = NULL; 1835 struct rm_priotracker in6_ifa_tracker; 1836 uint64_t genid; 1837 uint32_t flags; 1838 1839 ND6_ONLINK_LOCK(); 1840 ND6_RLOCK(); 1841 1842 /* 1843 * Check if there is a prefix that has a reachable advertising 1844 * router. 1845 */ 1846 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1847 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1848 break; 1849 } 1850 1851 /* 1852 * If we have no such prefix, check whether we still have a router 1853 * that does not advertise any prefixes. 1854 */ 1855 if (pr == NULL) { 1856 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 1857 struct nd_prefix *pr0; 1858 1859 LIST_FOREACH(pr0, &V_nd_prefix, ndpr_entry) { 1860 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1861 break; 1862 } 1863 if (pfxrtr != NULL) 1864 break; 1865 } 1866 } 1867 if (pr != NULL || (!TAILQ_EMPTY(&V_nd6_defrouter) && pfxrtr == NULL)) { 1868 /* 1869 * There is at least one prefix that has a reachable router, 1870 * or at least a router which probably does not advertise 1871 * any prefixes. The latter would be the case when we move 1872 * to a new link where we have a router that does not provide 1873 * prefixes and we configure an address by hand. 1874 * Detach prefixes which have no reachable advertising 1875 * router, and attach other prefixes. 1876 */ 1877 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1878 /* XXX: a link-local prefix should never be detached */ 1879 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1880 pr->ndpr_raf_onlink == 0 || 1881 pr->ndpr_raf_auto == 0) 1882 continue; 1883 1884 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1885 find_pfxlist_reachable_router(pr) == NULL) 1886 pr->ndpr_stateflags |= NDPRF_DETACHED; 1887 else if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1888 find_pfxlist_reachable_router(pr) != NULL) 1889 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1890 } 1891 } else { 1892 /* there is no prefix that has a reachable router */ 1893 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1894 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1895 pr->ndpr_raf_onlink == 0 || 1896 pr->ndpr_raf_auto == 0) 1897 continue; 1898 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1899 } 1900 } 1901 1902 /* 1903 * Remove each interface route associated with a (just) detached 1904 * prefix, and reinstall the interface route for a (just) attached 1905 * prefix. Note that all attempt of reinstallation does not 1906 * necessarily success, when a same prefix is shared among multiple 1907 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1908 * so we don't have to care about them. 1909 */ 1910 restart: 1911 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1912 char ip6buf[INET6_ADDRSTRLEN]; 1913 int e; 1914 1915 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1916 pr->ndpr_raf_onlink == 0 || 1917 pr->ndpr_raf_auto == 0) 1918 continue; 1919 1920 flags = pr->ndpr_stateflags & (NDPRF_DETACHED | NDPRF_ONLINK); 1921 if (flags == 0 || flags == (NDPRF_DETACHED | NDPRF_ONLINK)) { 1922 genid = V_nd6_list_genid; 1923 ND6_RUNLOCK(); 1924 if ((flags & NDPRF_ONLINK) != 0 && 1925 (e = nd6_prefix_offlink(pr)) != 0) { 1926 nd6log((LOG_ERR, 1927 "%s: failed to make %s/%d offlink " 1928 "(errno=%d)\n", __func__, 1929 ip6_sprintf(ip6buf, 1930 &pr->ndpr_prefix.sin6_addr), 1931 pr->ndpr_plen, e)); 1932 } else if ((flags & NDPRF_ONLINK) == 0 && 1933 (e = nd6_prefix_onlink(pr)) != 0) { 1934 nd6log((LOG_ERR, 1935 "%s: failed to make %s/%d onlink " 1936 "(errno=%d)\n", __func__, 1937 ip6_sprintf(ip6buf, 1938 &pr->ndpr_prefix.sin6_addr), 1939 pr->ndpr_plen, e)); 1940 } 1941 ND6_RLOCK(); 1942 if (genid != V_nd6_list_genid) 1943 goto restart; 1944 } 1945 } 1946 1947 /* 1948 * Changes on the prefix status might affect address status as well. 1949 * Make sure that all addresses derived from an attached prefix are 1950 * attached, and that all addresses derived from a detached prefix are 1951 * detached. Note, however, that a manually configured address should 1952 * always be attached. 1953 * The precise detection logic is same as the one for prefixes. 1954 */ 1955 IN6_IFADDR_RLOCK(&in6_ifa_tracker); 1956 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1957 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1958 continue; 1959 1960 if (ifa->ia6_ndpr == NULL) { 1961 /* 1962 * This can happen when we first configure the address 1963 * (i.e. the address exists, but the prefix does not). 1964 * XXX: complicated relationships... 1965 */ 1966 continue; 1967 } 1968 1969 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1970 break; 1971 } 1972 if (ifa) { 1973 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1974 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1975 continue; 1976 1977 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1978 continue; 1979 1980 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 1981 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1982 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1983 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1984 nd6_dad_start((struct ifaddr *)ifa, 0); 1985 } 1986 } else { 1987 ifa->ia6_flags |= IN6_IFF_DETACHED; 1988 } 1989 } 1990 } else { 1991 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1992 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1993 continue; 1994 1995 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1996 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1997 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1998 /* Do we need a delay in this case? */ 1999 nd6_dad_start((struct ifaddr *)ifa, 0); 2000 } 2001 } 2002 } 2003 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker); 2004 ND6_RUNLOCK(); 2005 ND6_ONLINK_UNLOCK(); 2006 } 2007 2008 static int 2009 nd6_prefix_onlink_rtrequest(struct nd_prefix *pr, struct ifaddr *ifa) 2010 { 2011 struct sockaddr_dl_short sdl; 2012 struct rtentry *rt; 2013 struct sockaddr_in6 mask6; 2014 u_long rtflags; 2015 int error, a_failure, fibnum, maxfib; 2016 2017 bzero(&mask6, sizeof(mask6)); 2018 mask6.sin6_len = sizeof(mask6); 2019 mask6.sin6_addr = pr->ndpr_mask; 2020 rtflags = (ifa->ifa_flags & ~IFA_RTSELF) | RTF_UP; 2021 2022 bzero(&sdl, sizeof(struct sockaddr_dl_short)); 2023 sdl.sdl_len = sizeof(struct sockaddr_dl_short); 2024 sdl.sdl_family = AF_LINK; 2025 sdl.sdl_type = ifa->ifa_ifp->if_type; 2026 sdl.sdl_index = ifa->ifa_ifp->if_index; 2027 2028 if(V_rt_add_addr_allfibs) { 2029 fibnum = 0; 2030 maxfib = rt_numfibs; 2031 } else { 2032 fibnum = ifa->ifa_ifp->if_fib; 2033 maxfib = fibnum + 1; 2034 } 2035 a_failure = 0; 2036 for (; fibnum < maxfib; fibnum++) { 2037 2038 rt = NULL; 2039 error = in6_rtrequest(RTM_ADD, 2040 (struct sockaddr *)&pr->ndpr_prefix, (struct sockaddr *)&sdl, 2041 (struct sockaddr *)&mask6, rtflags, &rt, fibnum); 2042 if (error != 0) { 2043 char ip6buf[INET6_ADDRSTRLEN]; 2044 char ip6bufg[INET6_ADDRSTRLEN]; 2045 char ip6bufm[INET6_ADDRSTRLEN]; 2046 struct sockaddr_in6 *sin6; 2047 2048 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 2049 nd6log((LOG_ERR, "%s: failed to add " 2050 "route for a prefix (%s/%d) on %s, gw=%s, mask=%s, " 2051 "flags=%lx errno = %d\n", __func__, 2052 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 2053 pr->ndpr_plen, if_name(pr->ndpr_ifp), 2054 ip6_sprintf(ip6bufg, &sin6->sin6_addr), 2055 ip6_sprintf(ip6bufm, &mask6.sin6_addr), 2056 rtflags, error)); 2057 2058 /* Save last error to return, see rtinit(). */ 2059 a_failure = error; 2060 continue; 2061 } 2062 2063 pr->ndpr_stateflags |= NDPRF_ONLINK; 2064 rt_routemsg(RTM_ADD, rt, pr->ndpr_ifp, 0, fibnum); 2065 } 2066 2067 /* Return the last error we got. */ 2068 return (a_failure); 2069 } 2070 2071 static int 2072 nd6_prefix_onlink(struct nd_prefix *pr) 2073 { 2074 struct epoch_tracker et; 2075 struct ifaddr *ifa; 2076 struct ifnet *ifp = pr->ndpr_ifp; 2077 struct nd_prefix *opr; 2078 char ip6buf[INET6_ADDRSTRLEN]; 2079 int error; 2080 2081 ND6_ONLINK_LOCK_ASSERT(); 2082 ND6_UNLOCK_ASSERT(); 2083 2084 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) 2085 return (EEXIST); 2086 2087 /* 2088 * Add the interface route associated with the prefix. Before 2089 * installing the route, check if there's the same prefix on another 2090 * interface, and the prefix has already installed the interface route. 2091 * Although such a configuration is expected to be rare, we explicitly 2092 * allow it. 2093 */ 2094 ND6_RLOCK(); 2095 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 2096 if (opr == pr) 2097 continue; 2098 2099 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 2100 continue; 2101 2102 if (!V_rt_add_addr_allfibs && 2103 opr->ndpr_ifp->if_fib != pr->ndpr_ifp->if_fib) 2104 continue; 2105 2106 if (opr->ndpr_plen == pr->ndpr_plen && 2107 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 2108 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 2109 ND6_RUNLOCK(); 2110 return (0); 2111 } 2112 } 2113 ND6_RUNLOCK(); 2114 2115 /* 2116 * We prefer link-local addresses as the associated interface address. 2117 */ 2118 /* search for a link-local addr */ 2119 NET_EPOCH_ENTER(et); 2120 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 2121 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 2122 if (ifa == NULL) { 2123 /* XXX: freebsd does not have ifa_ifwithaf */ 2124 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 2125 if (ifa->ifa_addr->sa_family == AF_INET6) { 2126 ifa_ref(ifa); 2127 break; 2128 } 2129 } 2130 /* should we care about ia6_flags? */ 2131 } 2132 if (ifa == NULL) { 2133 /* 2134 * This can still happen, when, for example, we receive an RA 2135 * containing a prefix with the L bit set and the A bit clear, 2136 * after removing all IPv6 addresses on the receiving 2137 * interface. This should, of course, be rare though. 2138 */ 2139 nd6log((LOG_NOTICE, 2140 "%s: failed to find any ifaddr to add route for a " 2141 "prefix(%s/%d) on %s\n", __func__, 2142 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 2143 pr->ndpr_plen, if_name(ifp))); 2144 error = 0; 2145 } else { 2146 error = nd6_prefix_onlink_rtrequest(pr, ifa); 2147 ifa_free(ifa); 2148 } 2149 NET_EPOCH_EXIT(et); 2150 2151 return (error); 2152 } 2153 2154 int 2155 nd6_prefix_offlink(struct nd_prefix *pr) 2156 { 2157 int error = 0; 2158 struct ifnet *ifp = pr->ndpr_ifp; 2159 struct nd_prefix *opr; 2160 struct sockaddr_in6 sa6, mask6; 2161 struct rtentry *rt; 2162 char ip6buf[INET6_ADDRSTRLEN]; 2163 uint64_t genid; 2164 int fibnum, maxfib, a_failure; 2165 struct epoch_tracker et; 2166 2167 ND6_ONLINK_LOCK_ASSERT(); 2168 ND6_UNLOCK_ASSERT(); 2169 2170 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) 2171 return (EEXIST); 2172 2173 bzero(&sa6, sizeof(sa6)); 2174 sa6.sin6_family = AF_INET6; 2175 sa6.sin6_len = sizeof(sa6); 2176 bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr, 2177 sizeof(struct in6_addr)); 2178 bzero(&mask6, sizeof(mask6)); 2179 mask6.sin6_family = AF_INET6; 2180 mask6.sin6_len = sizeof(sa6); 2181 bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr)); 2182 2183 if (V_rt_add_addr_allfibs) { 2184 fibnum = 0; 2185 maxfib = rt_numfibs; 2186 } else { 2187 fibnum = ifp->if_fib; 2188 maxfib = fibnum + 1; 2189 } 2190 2191 a_failure = 0; 2192 NET_EPOCH_ENTER(et); 2193 for (; fibnum < maxfib; fibnum++) { 2194 rt = NULL; 2195 error = in6_rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL, 2196 (struct sockaddr *)&mask6, 0, &rt, fibnum); 2197 if (error != 0) { 2198 /* Save last error to return, see rtinit(). */ 2199 a_failure = error; 2200 continue; 2201 } 2202 2203 /* report route deletion to the routing socket. */ 2204 rt_routemsg(RTM_DELETE, rt, ifp, 0, fibnum); 2205 } 2206 NET_EPOCH_EXIT(et); 2207 error = a_failure; 2208 a_failure = 1; 2209 if (error == 0) { 2210 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 2211 2212 /* 2213 * There might be the same prefix on another interface, 2214 * the prefix which could not be on-link just because we have 2215 * the interface route (see comments in nd6_prefix_onlink). 2216 * If there's one, try to make the prefix on-link on the 2217 * interface. 2218 */ 2219 ND6_RLOCK(); 2220 restart: 2221 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 2222 /* 2223 * KAME specific: detached prefixes should not be 2224 * on-link. 2225 */ 2226 if (opr == pr || (opr->ndpr_stateflags & 2227 (NDPRF_ONLINK | NDPRF_DETACHED)) != 0) 2228 continue; 2229 2230 if (opr->ndpr_plen == pr->ndpr_plen && 2231 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 2232 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 2233 int e; 2234 2235 genid = V_nd6_list_genid; 2236 ND6_RUNLOCK(); 2237 if ((e = nd6_prefix_onlink(opr)) != 0) { 2238 nd6log((LOG_ERR, 2239 "%s: failed to recover a prefix " 2240 "%s/%d from %s to %s (errno=%d)\n", 2241 __func__, ip6_sprintf(ip6buf, 2242 &opr->ndpr_prefix.sin6_addr), 2243 opr->ndpr_plen, if_name(ifp), 2244 if_name(opr->ndpr_ifp), e)); 2245 } else 2246 a_failure = 0; 2247 ND6_RLOCK(); 2248 if (genid != V_nd6_list_genid) 2249 goto restart; 2250 } 2251 } 2252 ND6_RUNLOCK(); 2253 } else { 2254 /* XXX: can we still set the NDPRF_ONLINK flag? */ 2255 nd6log((LOG_ERR, 2256 "%s: failed to delete route: %s/%d on %s (errno=%d)\n", 2257 __func__, ip6_sprintf(ip6buf, &sa6.sin6_addr), 2258 pr->ndpr_plen, if_name(ifp), error)); 2259 } 2260 2261 if (a_failure) 2262 lltable_prefix_free(AF_INET6, (struct sockaddr *)&sa6, 2263 (struct sockaddr *)&mask6, LLE_STATIC); 2264 2265 return (error); 2266 } 2267 2268 /* 2269 * ia0 - corresponding public address 2270 */ 2271 int 2272 in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay) 2273 { 2274 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 2275 struct in6_ifaddr *newia; 2276 struct in6_aliasreq ifra; 2277 int error; 2278 int trylimit = 3; /* XXX: adhoc value */ 2279 int updateflags; 2280 u_int32_t randid[2]; 2281 time_t vltime0, pltime0; 2282 2283 in6_prepare_ifra(&ifra, &ia0->ia_addr.sin6_addr, 2284 &ia0->ia_prefixmask.sin6_addr); 2285 2286 ifra.ifra_addr = ia0->ia_addr; /* XXX: do we need this ? */ 2287 /* clear the old IFID */ 2288 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, 2289 &ifra.ifra_prefixmask.sin6_addr); 2290 2291 again: 2292 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 2293 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 2294 nd6log((LOG_NOTICE, "%s: failed to find a good random IFID\n", 2295 __func__)); 2296 return (EINVAL); 2297 } 2298 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 2299 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 2300 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 2301 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 2302 2303 /* 2304 * in6_get_tmpifid() quite likely provided a unique interface ID. 2305 * However, we may still have a chance to see collision, because 2306 * there may be a time lag between generation of the ID and generation 2307 * of the address. So, we'll do one more sanity check. 2308 */ 2309 2310 if (in6_localip(&ifra.ifra_addr.sin6_addr) != 0) { 2311 if (trylimit-- > 0) { 2312 forcegen = 1; 2313 goto again; 2314 } 2315 2316 /* Give up. Something strange should have happened. */ 2317 nd6log((LOG_NOTICE, "%s: failed to find a unique random IFID\n", 2318 __func__)); 2319 return (EEXIST); 2320 } 2321 2322 /* 2323 * The Valid Lifetime is the lower of the Valid Lifetime of the 2324 * public address or TEMP_VALID_LIFETIME. 2325 * The Preferred Lifetime is the lower of the Preferred Lifetime 2326 * of the public address or TEMP_PREFERRED_LIFETIME - 2327 * DESYNC_FACTOR. 2328 */ 2329 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 2330 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 2331 (ia0->ia6_lifetime.ia6t_vltime - 2332 (time_uptime - ia0->ia6_updatetime)); 2333 if (vltime0 > V_ip6_temp_valid_lifetime) 2334 vltime0 = V_ip6_temp_valid_lifetime; 2335 } else 2336 vltime0 = V_ip6_temp_valid_lifetime; 2337 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 2338 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 2339 (ia0->ia6_lifetime.ia6t_pltime - 2340 (time_uptime - ia0->ia6_updatetime)); 2341 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){ 2342 pltime0 = V_ip6_temp_preferred_lifetime - 2343 V_ip6_desync_factor; 2344 } 2345 } else 2346 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor; 2347 ifra.ifra_lifetime.ia6t_vltime = vltime0; 2348 ifra.ifra_lifetime.ia6t_pltime = pltime0; 2349 2350 /* 2351 * A temporary address is created only if this calculated Preferred 2352 * Lifetime is greater than REGEN_ADVANCE time units. 2353 */ 2354 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance) 2355 return (0); 2356 2357 /* XXX: scope zone ID? */ 2358 2359 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2360 2361 /* allocate ifaddr structure, link into chain, etc. */ 2362 updateflags = 0; 2363 if (delay) 2364 updateflags |= IN6_IFAUPDATE_DADDELAY; 2365 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 2366 return (error); 2367 2368 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2369 if (newia == NULL) { /* XXX: can it happen? */ 2370 nd6log((LOG_ERR, 2371 "%s: ifa update succeeded, but we got no ifaddr\n", 2372 __func__)); 2373 return (EINVAL); /* XXX */ 2374 } 2375 newia->ia6_ndpr = ia0->ia6_ndpr; 2376 newia->ia6_ndpr->ndpr_addrcnt++; 2377 ifa_free(&newia->ia_ifa); 2378 2379 /* 2380 * A newly added address might affect the status of other addresses. 2381 * XXX: when the temporary address is generated with a new public 2382 * address, the onlink check is redundant. However, it would be safe 2383 * to do the check explicitly everywhere a new address is generated, 2384 * and, in fact, we surely need the check when we create a new 2385 * temporary address due to deprecation of an old temporary address. 2386 */ 2387 pfxlist_onlink_check(); 2388 2389 return (0); 2390 } 2391 2392 static int 2393 rt6_deleteroute(const struct rtentry *rt, const struct nhop_object *nh, 2394 void *arg) 2395 { 2396 struct in6_addr *gate = (struct in6_addr *)arg; 2397 int nh_rt_flags; 2398 2399 if (nh->gw_sa.sa_family != AF_INET6) 2400 return (0); 2401 2402 if (!IN6_ARE_ADDR_EQUAL(gate, &nh->gw6_sa.sin6_addr)) { 2403 return (0); 2404 } 2405 2406 /* 2407 * Do not delete a static route. 2408 * XXX: this seems to be a bit ad-hoc. Should we consider the 2409 * 'cloned' bit instead? 2410 */ 2411 nh_rt_flags = nhop_get_rtflags(nh); 2412 if ((nh_rt_flags & RTF_STATIC) != 0) 2413 return (0); 2414 2415 /* 2416 * We delete only host route. This means, in particular, we don't 2417 * delete default route. 2418 */ 2419 if ((nh_rt_flags & RTF_HOST) == 0) 2420 return (0); 2421 2422 return (1); 2423 #undef SIN6 2424 } 2425 2426 /* 2427 * Delete all the routing table entries that use the specified gateway. 2428 * XXX: this function causes search through all entries of routing table, so 2429 * it shouldn't be called when acting as a router. 2430 */ 2431 void 2432 rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2433 { 2434 2435 /* We'll care only link-local addresses */ 2436 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) 2437 return; 2438 2439 /* XXX Do we really need to walk any but the default FIB? */ 2440 rt_foreach_fib_walk_del(AF_INET6, rt6_deleteroute, (void *)gateway); 2441 } 2442 2443 int 2444 nd6_setdefaultiface(int ifindex) 2445 { 2446 int error = 0; 2447 2448 if (ifindex < 0 || V_if_index < ifindex) 2449 return (EINVAL); 2450 if (ifindex != 0 && !ifnet_byindex(ifindex)) 2451 return (EINVAL); 2452 2453 if (V_nd6_defifindex != ifindex) { 2454 V_nd6_defifindex = ifindex; 2455 if (V_nd6_defifindex > 0) 2456 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex); 2457 else 2458 V_nd6_defifp = NULL; 2459 2460 /* 2461 * Our current implementation assumes one-to-one maping between 2462 * interfaces and links, so it would be natural to use the 2463 * default interface as the default link. 2464 */ 2465 scope6_setdefault(V_nd6_defifp); 2466 } 2467 2468 return (error); 2469 } 2470 2471 bool 2472 nd6_defrouter_list_empty(void) 2473 { 2474 2475 return (TAILQ_EMPTY(&V_nd6_defrouter)); 2476 } 2477 2478 void 2479 nd6_defrouter_timer(void) 2480 { 2481 struct nd_defrouter *dr, *ndr; 2482 struct nd6_drhead drq; 2483 2484 TAILQ_INIT(&drq); 2485 2486 ND6_WLOCK(); 2487 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) 2488 if (dr->expire && dr->expire < time_uptime) 2489 defrouter_unlink(dr, &drq); 2490 ND6_WUNLOCK(); 2491 2492 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2493 TAILQ_REMOVE(&drq, dr, dr_entry); 2494 defrouter_del(dr); 2495 } 2496 } 2497 2498 /* 2499 * Nuke default router list entries toward ifp. 2500 * We defer removal of default router list entries that is installed in the 2501 * routing table, in order to keep additional side effects as small as possible. 2502 */ 2503 void 2504 nd6_defrouter_purge(struct ifnet *ifp) 2505 { 2506 struct nd_defrouter *dr, *ndr; 2507 struct nd6_drhead drq; 2508 2509 TAILQ_INIT(&drq); 2510 2511 ND6_WLOCK(); 2512 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) { 2513 if (dr->installed) 2514 continue; 2515 if (dr->ifp == ifp) 2516 defrouter_unlink(dr, &drq); 2517 } 2518 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) { 2519 if (!dr->installed) 2520 continue; 2521 if (dr->ifp == ifp) 2522 defrouter_unlink(dr, &drq); 2523 } 2524 ND6_WUNLOCK(); 2525 2526 /* Delete the unlinked router objects. */ 2527 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2528 TAILQ_REMOVE(&drq, dr, dr_entry); 2529 defrouter_del(dr); 2530 } 2531 } 2532 2533 void 2534 nd6_defrouter_flush_all(void) 2535 { 2536 struct nd_defrouter *dr; 2537 struct nd6_drhead drq; 2538 2539 TAILQ_INIT(&drq); 2540 2541 ND6_WLOCK(); 2542 while ((dr = TAILQ_FIRST(&V_nd6_defrouter)) != NULL) 2543 defrouter_unlink(dr, &drq); 2544 ND6_WUNLOCK(); 2545 2546 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2547 TAILQ_REMOVE(&drq, dr, dr_entry); 2548 defrouter_del(dr); 2549 } 2550 } 2551 2552 void 2553 nd6_defrouter_init(void) 2554 { 2555 2556 TAILQ_INIT(&V_nd6_defrouter); 2557 } 2558 2559 static int 2560 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS) 2561 { 2562 struct in6_defrouter d; 2563 struct nd_defrouter *dr; 2564 int error; 2565 2566 if (req->newptr != NULL) 2567 return (EPERM); 2568 2569 error = sysctl_wire_old_buffer(req, 0); 2570 if (error != 0) 2571 return (error); 2572 2573 bzero(&d, sizeof(d)); 2574 d.rtaddr.sin6_family = AF_INET6; 2575 d.rtaddr.sin6_len = sizeof(d.rtaddr); 2576 2577 ND6_RLOCK(); 2578 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 2579 d.rtaddr.sin6_addr = dr->rtaddr; 2580 error = sa6_recoverscope(&d.rtaddr); 2581 if (error != 0) 2582 break; 2583 d.flags = dr->raflags; 2584 d.rtlifetime = dr->rtlifetime; 2585 d.expire = dr->expire + (time_second - time_uptime); 2586 d.if_index = dr->ifp->if_index; 2587 error = SYSCTL_OUT(req, &d, sizeof(d)); 2588 if (error != 0) 2589 break; 2590 } 2591 ND6_RUNLOCK(); 2592 return (error); 2593 } 2594 SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist, 2595 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, 2596 NULL, 0, nd6_sysctl_drlist, "S,in6_defrouter", 2597 "NDP default router list"); 2598