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 #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/refcount.h> 43 #include <sys/socket.h> 44 #include <sys/sockio.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/lock.h> 48 #include <sys/errno.h> 49 #include <sys/rmlock.h> 50 #include <sys/rwlock.h> 51 #include <sys/sysctl.h> 52 #include <sys/syslog.h> 53 #include <sys/queue.h> 54 #include <sys/random.h> 55 56 #include <net/if.h> 57 #include <net/if_var.h> 58 #include <net/if_private.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/radix.h> 65 #include <net/vnet.h> 66 67 #include <netinet/in.h> 68 #include <net/if_llatbl.h> 69 #include <netinet6/in6_var.h> 70 #include <netinet6/in6_ifattach.h> 71 #include <netinet/ip6.h> 72 #include <netinet6/ip6_var.h> 73 #include <netinet6/nd6.h> 74 #include <netinet/icmp6.h> 75 #include <netinet6/scope6_var.h> 76 77 static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 78 static int prelist_update(struct nd_prefixctl *, struct nd_defrouter *, 79 struct mbuf *, int); 80 static int nd6_prefix_onlink(struct nd_prefix *); 81 static int in6_get_tmp_ifid(struct in6_aliasreq *); 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(uint32_t, ip6_temp_max_desync_factor) = TEMP_MAX_DESYNC_FACTOR_BASE; 98 VNET_DEFINE(u_int32_t, ip6_temp_preferred_lifetime) = DEF_TEMP_PREFERRED_LIFETIME; 99 VNET_DEFINE(u_int32_t, ip6_temp_valid_lifetime) = DEF_TEMP_VALID_LIFETIME; 100 101 VNET_DEFINE(int, ip6_temp_regen_advance) = TEMPADDR_REGEN_ADVANCE; 102 103 #ifdef EXPERIMENTAL 104 VNET_DEFINE_STATIC(int, nd6_ignore_ipv6_only_ra) = 1; 105 #define V_nd6_ignore_ipv6_only_ra VNET(nd6_ignore_ipv6_only_ra) 106 SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, 107 nd6_ignore_ipv6_only_ra, CTLFLAG_VNET | CTLFLAG_RW, 108 &VNET_NAME(nd6_ignore_ipv6_only_ra), 0, 109 "Ignore the 'IPv6-Only flag' in RA messages in compliance with " 110 "draft-ietf-6man-ipv6only-flag"); 111 #endif 112 113 /* RTPREF_MEDIUM has to be 0! */ 114 #define RTPREF_HIGH 1 115 #define RTPREF_MEDIUM 0 116 #define RTPREF_LOW (-1) 117 #define RTPREF_RESERVED (-2) 118 #define RTPREF_INVALID (-3) /* internal */ 119 120 static void 121 defrouter_ref(struct nd_defrouter *dr) 122 { 123 124 refcount_acquire(&dr->refcnt); 125 } 126 127 void 128 defrouter_rele(struct nd_defrouter *dr) 129 { 130 131 if (refcount_release(&dr->refcnt)) 132 free(dr, M_IP6NDP); 133 } 134 135 /* 136 * Remove a router from the global list and optionally stash it in a 137 * caller-supplied queue. 138 */ 139 static void 140 defrouter_unlink(struct nd_defrouter *dr, struct nd6_drhead *drq) 141 { 142 143 ND6_WLOCK_ASSERT(); 144 145 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry); 146 V_nd6_list_genid++; 147 if (drq != NULL) 148 TAILQ_INSERT_TAIL(drq, dr, dr_entry); 149 } 150 151 /* 152 * Receive Router Solicitation Message - just for routers. 153 * Router solicitation/advertisement is mostly managed by userland program 154 * (rtadvd) so here we have no function like nd6_ra_output(). 155 * 156 * Based on RFC 2461 157 */ 158 void 159 nd6_rs_input(struct mbuf *m, int off, int icmp6len) 160 { 161 struct ifnet *ifp; 162 struct ip6_hdr *ip6; 163 struct nd_router_solicit *nd_rs; 164 struct in6_addr saddr6; 165 union nd_opts ndopts; 166 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 167 char *lladdr; 168 int lladdrlen; 169 170 ifp = m->m_pkthdr.rcvif; 171 172 /* 173 * Accept RS only when V_ip6_forwarding=1 and the interface has 174 * no ND6_IFF_ACCEPT_RTADV. 175 */ 176 if (!V_ip6_forwarding || ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) 177 goto freeit; 178 179 /* RFC 6980: Nodes MUST silently ignore fragments */ 180 if(m->m_flags & M_FRAGMENTED) 181 goto freeit; 182 183 /* Sanity checks */ 184 ip6 = mtod(m, struct ip6_hdr *); 185 if (__predict_false(ip6->ip6_hlim != 255)) { 186 ICMP6STAT_INC(icp6s_invlhlim); 187 nd6log((LOG_ERR, 188 "%s: invalid hlim (%d) from %s to %s on %s\n", __func__, 189 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 190 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 191 goto bad; 192 } 193 194 /* 195 * Don't update the neighbor cache, if src = ::. 196 * This indicates that the src has no IP address assigned yet. 197 */ 198 saddr6 = ip6->ip6_src; 199 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 200 goto freeit; 201 202 if (m->m_len < off + icmp6len) { 203 m = m_pullup(m, off + icmp6len); 204 if (m == NULL) { 205 IP6STAT_INC(ip6s_exthdrtoolong); 206 return; 207 } 208 } 209 ip6 = mtod(m, struct ip6_hdr *); 210 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off); 211 212 icmp6len -= sizeof(*nd_rs); 213 nd6_option_init(nd_rs + 1, icmp6len, &ndopts); 214 if (nd6_options(&ndopts) < 0) { 215 nd6log((LOG_INFO, 216 "%s: invalid ND option, ignored\n", __func__)); 217 /* nd6_options have incremented stats */ 218 goto freeit; 219 } 220 221 lladdr = NULL; 222 lladdrlen = 0; 223 if (ndopts.nd_opts_src_lladdr) { 224 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 225 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 226 } 227 228 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 229 nd6log((LOG_INFO, 230 "%s: lladdrlen mismatch for %s (if %d, RS packet %d)\n", 231 __func__, ip6_sprintf(ip6bufs, &saddr6), 232 ifp->if_addrlen, lladdrlen - 2)); 233 goto bad; 234 } 235 236 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0); 237 238 freeit: 239 m_freem(m); 240 return; 241 242 bad: 243 ICMP6STAT_INC(icp6s_badrs); 244 m_freem(m); 245 } 246 247 #ifdef EXPERIMENTAL 248 /* 249 * An initial update routine for draft-ietf-6man-ipv6only-flag. 250 * We need to iterate over all default routers for the given 251 * interface to see whether they are all advertising the "S" 252 * (IPv6-Only) flag. If they do set, otherwise unset, the 253 * interface flag we later use to filter on. 254 */ 255 static void 256 defrtr_ipv6_only_ifp(struct ifnet *ifp) 257 { 258 struct nd_defrouter *dr; 259 bool ipv6_only, ipv6_only_old; 260 #ifdef INET 261 struct epoch_tracker et; 262 struct ifaddr *ifa; 263 bool has_ipv4_addr; 264 #endif 265 266 if (V_nd6_ignore_ipv6_only_ra != 0) 267 return; 268 269 ipv6_only = true; 270 ND6_RLOCK(); 271 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 272 if (dr->ifp == ifp && 273 (dr->raflags & ND_RA_FLAG_IPV6_ONLY) == 0) 274 ipv6_only = false; 275 ND6_RUNLOCK(); 276 277 IF_AFDATA_WLOCK(ifp); 278 ipv6_only_old = ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY; 279 IF_AFDATA_WUNLOCK(ifp); 280 281 /* If nothing changed, we have an early exit. */ 282 if (ipv6_only == ipv6_only_old) 283 return; 284 285 #ifdef INET 286 /* 287 * Should we want to set the IPV6-ONLY flag, check if the 288 * interface has a non-0/0 and non-link-local IPv4 address 289 * configured on it. If it has we will assume working 290 * IPv4 operations and will clear the interface flag. 291 */ 292 has_ipv4_addr = false; 293 if (ipv6_only) { 294 NET_EPOCH_ENTER(et); 295 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 296 if (ifa->ifa_addr->sa_family != AF_INET) 297 continue; 298 if (in_canforward( 299 satosin(ifa->ifa_addr)->sin_addr)) { 300 has_ipv4_addr = true; 301 break; 302 } 303 } 304 NET_EPOCH_EXIT(et); 305 } 306 if (ipv6_only && has_ipv4_addr) { 307 log(LOG_NOTICE, "%s rcvd RA w/ IPv6-Only flag set but has IPv4 " 308 "configured, ignoring IPv6-Only flag.\n", ifp->if_xname); 309 ipv6_only = false; 310 } 311 #endif 312 313 IF_AFDATA_WLOCK(ifp); 314 if (ipv6_only) 315 ND_IFINFO(ifp)->flags |= ND6_IFF_IPV6_ONLY; 316 else 317 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IPV6_ONLY; 318 IF_AFDATA_WUNLOCK(ifp); 319 320 #ifdef notyet 321 /* Send notification of flag change. */ 322 #endif 323 } 324 325 static void 326 defrtr_ipv6_only_ipf_down(struct ifnet *ifp) 327 { 328 329 IF_AFDATA_WLOCK(ifp); 330 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IPV6_ONLY; 331 IF_AFDATA_WUNLOCK(ifp); 332 } 333 #endif /* EXPERIMENTAL */ 334 335 void 336 nd6_ifnet_link_event(void *arg __unused, struct ifnet *ifp, int linkstate) 337 { 338 339 /* 340 * XXX-BZ we might want to trigger re-evaluation of our default router 341 * availability. E.g., on link down the default router might be 342 * unreachable but a different interface might still have connectivity. 343 */ 344 345 #ifdef EXPERIMENTAL 346 if (linkstate == LINK_STATE_DOWN) 347 defrtr_ipv6_only_ipf_down(ifp); 348 #endif 349 } 350 351 /* 352 * Receive Router Advertisement Message. 353 * 354 * Based on RFC 2461 355 * TODO: on-link bit on prefix information 356 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing 357 */ 358 void 359 nd6_ra_input(struct mbuf *m, int off, int icmp6len) 360 { 361 struct ifnet *ifp; 362 struct nd_ifinfo *ndi; 363 struct ip6_hdr *ip6; 364 struct nd_router_advert *nd_ra; 365 struct in6_addr saddr6; 366 struct nd_defrouter *dr; 367 union nd_opts ndopts; 368 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 369 int mcast; 370 371 /* 372 * We only accept RAs only when the per-interface flag 373 * ND6_IFF_ACCEPT_RTADV is on the receiving interface. 374 */ 375 ifp = m->m_pkthdr.rcvif; 376 ndi = ND_IFINFO(ifp); 377 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV)) 378 goto freeit; 379 380 /* RFC 6980: Nodes MUST silently ignore fragments */ 381 if(m->m_flags & M_FRAGMENTED) 382 goto freeit; 383 384 ip6 = mtod(m, struct ip6_hdr *); 385 if (__predict_false(ip6->ip6_hlim != 255)) { 386 ICMP6STAT_INC(icp6s_invlhlim); 387 nd6log((LOG_ERR, 388 "%s: invalid hlim (%d) from %s to %s on %s\n", __func__, 389 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 390 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 391 goto bad; 392 } 393 394 saddr6 = ip6->ip6_src; 395 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 396 nd6log((LOG_ERR, 397 "%s: src %s is not link-local\n", __func__, 398 ip6_sprintf(ip6bufs, &saddr6))); 399 goto bad; 400 } 401 402 if (m->m_len < off + icmp6len) { 403 m = m_pullup(m, off + icmp6len); 404 if (m == NULL) { 405 IP6STAT_INC(ip6s_exthdrtoolong); 406 return; 407 } 408 } 409 ip6 = mtod(m, struct ip6_hdr *); 410 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off); 411 412 icmp6len -= sizeof(*nd_ra); 413 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 414 if (nd6_options(&ndopts) < 0) { 415 nd6log((LOG_INFO, 416 "%s: invalid ND option, ignored\n", __func__)); 417 /* nd6_options have incremented stats */ 418 goto freeit; 419 } 420 421 mcast = 0; 422 dr = NULL; 423 { 424 struct nd_defrouter dr0; 425 u_int32_t advreachable = nd_ra->nd_ra_reachable; 426 427 /* remember if this is a multicasted advertisement */ 428 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 429 mcast = 1; 430 431 bzero(&dr0, sizeof(dr0)); 432 dr0.rtaddr = saddr6; 433 dr0.raflags = nd_ra->nd_ra_flags_reserved; 434 /* 435 * Effectively-disable routes from RA messages when 436 * ND6_IFF_NO_RADR enabled on the receiving interface or 437 * (ip6.forwarding == 1 && ip6.rfc6204w3 != 1). 438 */ 439 if (ndi->flags & ND6_IFF_NO_RADR) 440 dr0.rtlifetime = 0; 441 else if (V_ip6_forwarding && !V_ip6_rfc6204w3) 442 dr0.rtlifetime = 0; 443 else 444 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 445 dr0.expire = time_uptime + dr0.rtlifetime; 446 dr0.ifp = ifp; 447 /* unspecified or not? (RFC 2461 6.3.4) */ 448 if (advreachable) { 449 advreachable = ntohl(advreachable); 450 if (advreachable <= MAX_REACHABLE_TIME && 451 ndi->basereachable != advreachable) { 452 ndi->basereachable = advreachable; 453 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 454 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */ 455 } 456 } 457 if (nd_ra->nd_ra_retransmit) 458 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 459 if (nd_ra->nd_ra_curhoplimit) { 460 if (ndi->chlim < nd_ra->nd_ra_curhoplimit) 461 ndi->chlim = nd_ra->nd_ra_curhoplimit; 462 else if (ndi->chlim != nd_ra->nd_ra_curhoplimit) { 463 log(LOG_ERR, "RA with a lower CurHopLimit sent from " 464 "%s on %s (current = %d, received = %d). " 465 "Ignored.\n", ip6_sprintf(ip6bufs, &ip6->ip6_src), 466 if_name(ifp), ndi->chlim, nd_ra->nd_ra_curhoplimit); 467 } 468 } 469 dr = defrtrlist_update(&dr0); 470 #ifdef EXPERIMENTAL 471 defrtr_ipv6_only_ifp(ifp); 472 #endif 473 } 474 475 /* 476 * prefix 477 */ 478 if (ndopts.nd_opts_pi) { 479 struct nd_opt_hdr *pt; 480 struct nd_opt_prefix_info *pi = NULL; 481 struct nd_prefixctl pr; 482 483 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 484 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 485 pt = (struct nd_opt_hdr *)((caddr_t)pt + 486 (pt->nd_opt_len << 3))) { 487 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 488 continue; 489 pi = (struct nd_opt_prefix_info *)pt; 490 491 if (pi->nd_opt_pi_len != 4) { 492 nd6log((LOG_INFO, 493 "%s: invalid option len %d for prefix " 494 "information option, ignored\n", __func__, 495 pi->nd_opt_pi_len)); 496 continue; 497 } 498 499 if (128 < pi->nd_opt_pi_prefix_len) { 500 nd6log((LOG_INFO, 501 "%s: invalid prefix len %d for prefix " 502 "information option, ignored\n", __func__, 503 pi->nd_opt_pi_prefix_len)); 504 continue; 505 } 506 507 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 508 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 509 nd6log((LOG_INFO, 510 "%s: invalid prefix %s, ignored\n", 511 __func__, ip6_sprintf(ip6bufs, 512 &pi->nd_opt_pi_prefix))); 513 continue; 514 } 515 516 bzero(&pr, sizeof(pr)); 517 pr.ndpr_prefix.sin6_family = AF_INET6; 518 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix); 519 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix; 520 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 521 522 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 523 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 524 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 525 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 526 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 527 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 528 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 529 (void)prelist_update(&pr, dr, m, mcast); 530 } 531 } 532 if (dr != NULL) { 533 defrouter_rele(dr); 534 dr = NULL; 535 } 536 537 /* 538 * MTU 539 */ 540 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 541 u_long mtu; 542 u_long maxmtu; 543 544 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 545 546 /* lower bound */ 547 if (mtu < IPV6_MMTU) { 548 nd6log((LOG_INFO, "%s: bogus mtu option mtu=%lu sent " 549 "from %s, ignoring\n", __func__, 550 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src))); 551 goto skip; 552 } 553 554 /* upper bound */ 555 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 556 ? ndi->maxmtu : ifp->if_mtu; 557 if (mtu <= maxmtu) { 558 if (ndi->linkmtu != mtu) { 559 ndi->linkmtu = mtu; 560 rt_updatemtu(ifp); 561 } 562 } else { 563 nd6log((LOG_INFO, "%s: bogus mtu=%lu sent from %s; " 564 "exceeds maxmtu %lu, ignoring\n", __func__, 565 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu)); 566 } 567 } 568 569 skip: 570 571 /* 572 * Source link layer address 573 */ 574 { 575 char *lladdr = NULL; 576 int lladdrlen = 0; 577 578 if (ndopts.nd_opts_src_lladdr) { 579 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 580 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 581 } 582 583 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 584 nd6log((LOG_INFO, 585 "%s: lladdrlen mismatch for %s (if %d, RA packet %d)\n", 586 __func__, ip6_sprintf(ip6bufs, &saddr6), 587 ifp->if_addrlen, lladdrlen - 2)); 588 goto bad; 589 } 590 591 nd6_cache_lladdr(ifp, &saddr6, lladdr, 592 lladdrlen, ND_ROUTER_ADVERT, 0); 593 594 /* 595 * Installing a link-layer address might change the state of the 596 * router's neighbor cache, which might also affect our on-link 597 * detection of adveritsed prefixes. 598 */ 599 pfxlist_onlink_check(); 600 } 601 602 freeit: 603 m_freem(m); 604 return; 605 606 bad: 607 ICMP6STAT_INC(icp6s_badra); 608 m_freem(m); 609 } 610 611 /* PFXRTR */ 612 static struct nd_pfxrouter * 613 pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 614 { 615 struct nd_pfxrouter *search; 616 617 ND6_LOCK_ASSERT(); 618 619 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) { 620 if (search->router == dr) 621 break; 622 } 623 return (search); 624 } 625 626 static void 627 pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 628 { 629 struct nd_pfxrouter *new; 630 bool update; 631 632 ND6_UNLOCK_ASSERT(); 633 634 ND6_RLOCK(); 635 if (pfxrtr_lookup(pr, dr) != NULL) { 636 ND6_RUNLOCK(); 637 return; 638 } 639 ND6_RUNLOCK(); 640 641 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 642 if (new == NULL) 643 return; 644 defrouter_ref(dr); 645 new->router = dr; 646 647 ND6_WLOCK(); 648 if (pfxrtr_lookup(pr, dr) == NULL) { 649 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 650 update = true; 651 } else { 652 /* We lost a race to add the reference. */ 653 defrouter_rele(dr); 654 free(new, M_IP6NDP); 655 update = false; 656 } 657 ND6_WUNLOCK(); 658 659 if (update) 660 pfxlist_onlink_check(); 661 } 662 663 static void 664 pfxrtr_del(struct nd_pfxrouter *pfr) 665 { 666 667 ND6_WLOCK_ASSERT(); 668 669 LIST_REMOVE(pfr, pfr_entry); 670 defrouter_rele(pfr->router); 671 free(pfr, M_IP6NDP); 672 } 673 674 /* Default router list processing sub routines. */ 675 static void 676 defrouter_addreq(struct nd_defrouter *new) 677 { 678 uint32_t fibnum = new->ifp->if_fib; 679 struct rib_cmd_info rc = {}; 680 int error = 0; 681 682 NET_EPOCH_ASSERT(); 683 684 struct sockaddr_in6 gw = { 685 .sin6_family = AF_INET6, 686 .sin6_len = sizeof(struct sockaddr_in6), 687 .sin6_addr = new->rtaddr, 688 }; 689 690 error = rib_add_default_route(fibnum, AF_INET6, new->ifp, 691 (struct sockaddr *)&gw, &rc); 692 693 if (error == 0) { 694 struct nhop_object *nh = nhop_select_func(rc.rc_nh_new, 0); 695 rt_routemsg(RTM_ADD, rc.rc_rt, nh, fibnum); 696 new->installed = 1; 697 } 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 uint32_t fibnum = dr->ifp->if_fib; 709 struct epoch_tracker et; 710 struct rib_cmd_info rc; 711 int error; 712 713 struct sockaddr_in6 dst = { 714 .sin6_family = AF_INET6, 715 .sin6_len = sizeof(struct sockaddr_in6), 716 }; 717 718 struct sockaddr_in6 gw = { 719 .sin6_family = AF_INET6, 720 .sin6_len = sizeof(struct sockaddr_in6), 721 .sin6_addr = dr->rtaddr, 722 }; 723 724 NET_EPOCH_ENTER(et); 725 error = rib_del_route_px(fibnum, (struct sockaddr *)&dst, 0, 726 rib_match_gw, (struct sockaddr *)&gw, 0, &rc); 727 if (error == 0) { 728 struct nhop_object *nh = nhop_select_func(rc.rc_nh_old, 0); 729 rt_routemsg(RTM_DELETE, rc.rc_rt, nh, fibnum); 730 } 731 NET_EPOCH_EXIT(et); 732 733 dr->installed = 0; 734 } 735 736 static void 737 defrouter_del(struct nd_defrouter *dr) 738 { 739 struct nd_defrouter *deldr = NULL; 740 struct nd_prefix *pr; 741 struct nd_pfxrouter *pfxrtr; 742 743 ND6_UNLOCK_ASSERT(); 744 745 /* 746 * Flush all the routing table entries that use the router 747 * as a next hop. 748 */ 749 if (ND_IFINFO(dr->ifp)->flags & ND6_IFF_ACCEPT_RTADV) 750 rt6_flush(&dr->rtaddr, dr->ifp); 751 752 #ifdef EXPERIMENTAL 753 defrtr_ipv6_only_ifp(dr->ifp); 754 #endif 755 756 if (dr->installed) { 757 deldr = dr; 758 defrouter_delreq(dr); 759 } 760 761 /* 762 * Also delete all the pointers to the router in each prefix lists. 763 */ 764 ND6_WLOCK(); 765 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 766 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 767 pfxrtr_del(pfxrtr); 768 } 769 ND6_WUNLOCK(); 770 771 pfxlist_onlink_check(); 772 773 /* 774 * If the router is the primary one, choose a new one. 775 * Note that defrouter_select_fib() will remove the current 776 * gateway from the routing table. 777 */ 778 if (deldr) 779 defrouter_select_fib(deldr->ifp->if_fib); 780 781 /* 782 * Release the list reference. 783 */ 784 defrouter_rele(dr); 785 } 786 787 struct nd_defrouter * 788 defrouter_lookup_locked(const struct in6_addr *addr, struct ifnet *ifp) 789 { 790 struct nd_defrouter *dr; 791 792 ND6_LOCK_ASSERT(); 793 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 794 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) { 795 defrouter_ref(dr); 796 return (dr); 797 } 798 return (NULL); 799 } 800 801 struct nd_defrouter * 802 defrouter_lookup(const struct in6_addr *addr, struct ifnet *ifp) 803 { 804 struct nd_defrouter *dr; 805 806 ND6_RLOCK(); 807 dr = defrouter_lookup_locked(addr, ifp); 808 ND6_RUNLOCK(); 809 return (dr); 810 } 811 812 /* 813 * Remove all default routes from default router list. 814 */ 815 void 816 defrouter_reset(void) 817 { 818 struct nd_defrouter *dr, **dra; 819 int count, i; 820 821 count = i = 0; 822 823 /* 824 * We can't delete routes with the ND lock held, so make a copy of the 825 * current default router list and use that when deleting routes. 826 */ 827 ND6_RLOCK(); 828 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 829 count++; 830 ND6_RUNLOCK(); 831 832 dra = malloc(count * sizeof(*dra), M_TEMP, M_WAITOK | M_ZERO); 833 834 ND6_RLOCK(); 835 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 836 if (i == count) 837 break; 838 defrouter_ref(dr); 839 dra[i++] = dr; 840 } 841 ND6_RUNLOCK(); 842 843 for (i = 0; i < count && dra[i] != NULL; i++) { 844 defrouter_delreq(dra[i]); 845 defrouter_rele(dra[i]); 846 } 847 free(dra, M_TEMP); 848 849 /* 850 * XXX should we also nuke any default routers in the kernel, by 851 * going through them by rtalloc1()? 852 */ 853 } 854 855 /* 856 * Look up a matching default router list entry and remove it. Returns true if a 857 * matching entry was found, false otherwise. 858 */ 859 bool 860 defrouter_remove(struct in6_addr *addr, struct ifnet *ifp) 861 { 862 struct nd_defrouter *dr; 863 864 ND6_WLOCK(); 865 dr = defrouter_lookup_locked(addr, ifp); 866 if (dr == NULL) { 867 ND6_WUNLOCK(); 868 return (false); 869 } 870 871 defrouter_unlink(dr, NULL); 872 ND6_WUNLOCK(); 873 defrouter_del(dr); 874 defrouter_rele(dr); 875 return (true); 876 } 877 878 /* 879 * for default router selection 880 * regards router-preference field as a 2-bit signed integer 881 */ 882 static int 883 rtpref(struct nd_defrouter *dr) 884 { 885 switch (dr->raflags & ND_RA_FLAG_RTPREF_MASK) { 886 case ND_RA_FLAG_RTPREF_HIGH: 887 return (RTPREF_HIGH); 888 case ND_RA_FLAG_RTPREF_MEDIUM: 889 case ND_RA_FLAG_RTPREF_RSV: 890 return (RTPREF_MEDIUM); 891 case ND_RA_FLAG_RTPREF_LOW: 892 return (RTPREF_LOW); 893 default: 894 /* 895 * This case should never happen. If it did, it would mean a 896 * serious bug of kernel internal. We thus always bark here. 897 * Or, can we even panic? 898 */ 899 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->raflags); 900 return (RTPREF_INVALID); 901 } 902 /* NOTREACHED */ 903 } 904 905 static bool 906 is_dr_reachable(const struct nd_defrouter *dr) { 907 struct llentry *ln = NULL; 908 909 ln = nd6_lookup(&dr->rtaddr, LLE_SF(AF_INET6, 0), dr->ifp); 910 if (ln == NULL) 911 return (false); 912 bool reachable = ND6_IS_LLINFO_PROBREACH(ln); 913 LLE_RUNLOCK(ln); 914 return reachable; 915 } 916 917 /* 918 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 919 * draft-ietf-ipngwg-router-selection: 920 * 1) Routers that are reachable or probably reachable should be preferred. 921 * If we have more than one (probably) reachable router, prefer ones 922 * with the highest router preference. 923 * 2) When no routers on the list are known to be reachable or 924 * probably reachable, routers SHOULD be selected in a round-robin 925 * fashion, regardless of router preference values. 926 * 3) If the Default Router List is empty, assume that all 927 * destinations are on-link. 928 * 929 * We assume nd_defrouter is sorted by router preference value. 930 * Since the code below covers both with and without router preference cases, 931 * we do not need to classify the cases by ifdef. 932 * 933 * At this moment, we do not try to install more than one default router, 934 * even when the multipath routing is available, because we're not sure about 935 * the benefits for stub hosts comparing to the risk of making the code 936 * complicated and the possibility of introducing bugs. 937 * 938 * We maintain a single list of routers for multiple FIBs, only considering one 939 * at a time based on the receiving interface's FIB. If @fibnum is RT_ALL_FIBS, 940 * we do the whole thing multiple times. 941 */ 942 void 943 defrouter_select_fib(int fibnum) 944 { 945 struct epoch_tracker et; 946 struct nd_defrouter *dr, *selected_dr, *installed_dr; 947 948 if (fibnum == RT_ALL_FIBS) { 949 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) { 950 defrouter_select_fib(fibnum); 951 } 952 return; 953 } 954 955 ND6_RLOCK(); 956 /* 957 * Let's handle easy case (3) first: 958 * If default router list is empty, there's nothing to be done. 959 */ 960 if (TAILQ_EMPTY(&V_nd6_defrouter)) { 961 ND6_RUNLOCK(); 962 return; 963 } 964 965 /* 966 * Search for a (probably) reachable router from the list. 967 * We just pick up the first reachable one (if any), assuming that 968 * the ordering rule of the list described in defrtrlist_update(). 969 */ 970 selected_dr = installed_dr = NULL; 971 NET_EPOCH_ENTER(et); 972 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 973 if (dr->ifp->if_fib != fibnum) 974 continue; 975 976 if (selected_dr == NULL && is_dr_reachable(dr)) { 977 selected_dr = dr; 978 defrouter_ref(selected_dr); 979 } 980 981 if (dr->installed) { 982 if (installed_dr == NULL) { 983 installed_dr = dr; 984 defrouter_ref(installed_dr); 985 } else { 986 /* 987 * this should not happen. 988 * warn for diagnosis. 989 */ 990 log(LOG_ERR, "defrouter_select_fib: more than " 991 "one router is installed\n"); 992 } 993 } 994 } 995 996 /* 997 * If none of the default routers was found to be reachable, 998 * round-robin the list regardless of preference. 999 * Otherwise, if we have an installed router, check if the selected 1000 * (reachable) router should really be preferred to the installed one. 1001 * We only prefer the new router when the old one is not reachable 1002 * or when the new one has a really higher preference value. 1003 */ 1004 if (selected_dr == NULL) { 1005 if (installed_dr == NULL || 1006 TAILQ_NEXT(installed_dr, dr_entry) == NULL) 1007 dr = TAILQ_FIRST(&V_nd6_defrouter); 1008 else 1009 dr = TAILQ_NEXT(installed_dr, dr_entry); 1010 1011 /* Ensure we select a router for this FIB. */ 1012 TAILQ_FOREACH_FROM(dr, &V_nd6_defrouter, dr_entry) { 1013 if (dr->ifp->if_fib == fibnum) { 1014 selected_dr = dr; 1015 defrouter_ref(selected_dr); 1016 break; 1017 } 1018 } 1019 } else if (installed_dr != NULL) { 1020 if (is_dr_reachable(installed_dr) && 1021 rtpref(selected_dr) <= rtpref(installed_dr)) { 1022 defrouter_rele(selected_dr); 1023 selected_dr = installed_dr; 1024 } 1025 } 1026 ND6_RUNLOCK(); 1027 1028 /* 1029 * If we selected a router for this FIB and it's different 1030 * than the installed one, remove the installed router and 1031 * install the selected one in its place. 1032 */ 1033 if (installed_dr != selected_dr) { 1034 if (installed_dr != NULL) { 1035 defrouter_delreq(installed_dr); 1036 defrouter_rele(installed_dr); 1037 } 1038 if (selected_dr != NULL) 1039 defrouter_addreq(selected_dr); 1040 } 1041 if (selected_dr != NULL) 1042 defrouter_rele(selected_dr); 1043 NET_EPOCH_EXIT(et); 1044 } 1045 1046 static struct nd_defrouter * 1047 defrtrlist_update(struct nd_defrouter *new) 1048 { 1049 struct nd_defrouter *dr, *n; 1050 uint64_t genid; 1051 int oldpref; 1052 bool writelocked; 1053 1054 if (new->rtlifetime == 0) { 1055 defrouter_remove(&new->rtaddr, new->ifp); 1056 return (NULL); 1057 } 1058 1059 ND6_RLOCK(); 1060 writelocked = false; 1061 restart: 1062 dr = defrouter_lookup_locked(&new->rtaddr, new->ifp); 1063 if (dr != NULL) { 1064 oldpref = rtpref(dr); 1065 1066 /* override */ 1067 dr->raflags = new->raflags; /* XXX flag check */ 1068 dr->rtlifetime = new->rtlifetime; 1069 dr->expire = new->expire; 1070 1071 /* 1072 * If the preference does not change, there's no need 1073 * to sort the entries. Also make sure the selected 1074 * router is still installed in the kernel. 1075 */ 1076 if (dr->installed && rtpref(new) == oldpref) { 1077 if (writelocked) 1078 ND6_WUNLOCK(); 1079 else 1080 ND6_RUNLOCK(); 1081 return (dr); 1082 } 1083 } 1084 1085 /* 1086 * The router needs to be reinserted into the default router 1087 * list, so upgrade to a write lock. If that fails and the list 1088 * has potentially changed while the lock was dropped, we'll 1089 * redo the lookup with the write lock held. 1090 */ 1091 if (!writelocked) { 1092 writelocked = true; 1093 if (!ND6_TRY_UPGRADE()) { 1094 genid = V_nd6_list_genid; 1095 ND6_RUNLOCK(); 1096 ND6_WLOCK(); 1097 if (genid != V_nd6_list_genid) 1098 goto restart; 1099 } 1100 } 1101 1102 if (dr != NULL) { 1103 /* 1104 * The preferred router may have changed, so relocate this 1105 * router. 1106 */ 1107 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry); 1108 n = dr; 1109 } else { 1110 n = malloc(sizeof(*n), M_IP6NDP, M_NOWAIT | M_ZERO); 1111 if (n == NULL) { 1112 ND6_WUNLOCK(); 1113 return (NULL); 1114 } 1115 memcpy(n, new, sizeof(*n)); 1116 /* Initialize with an extra reference for the caller. */ 1117 refcount_init(&n->refcnt, 2); 1118 } 1119 1120 /* 1121 * Insert the new router in the Default Router List; 1122 * The Default Router List should be in the descending order 1123 * of router-preferece. Routers with the same preference are 1124 * sorted in the arriving time order. 1125 */ 1126 1127 /* insert at the end of the group */ 1128 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 1129 if (rtpref(n) > rtpref(dr)) 1130 break; 1131 } 1132 if (dr != NULL) 1133 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 1134 else 1135 TAILQ_INSERT_TAIL(&V_nd6_defrouter, n, dr_entry); 1136 V_nd6_list_genid++; 1137 ND6_WUNLOCK(); 1138 1139 defrouter_select_fib(new->ifp->if_fib); 1140 1141 return (n); 1142 } 1143 1144 static int 1145 in6_init_prefix_ltimes(struct nd_prefix *ndpr) 1146 { 1147 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 1148 ndpr->ndpr_preferred = 0; 1149 else 1150 ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime; 1151 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1152 ndpr->ndpr_expire = 0; 1153 else 1154 ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime; 1155 1156 return 0; 1157 } 1158 1159 static void 1160 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6) 1161 { 1162 /* init ia6t_expire */ 1163 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 1164 lt6->ia6t_expire = 0; 1165 else { 1166 lt6->ia6t_expire = time_uptime; 1167 lt6->ia6t_expire += lt6->ia6t_vltime; 1168 } 1169 1170 /* init ia6t_preferred */ 1171 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 1172 lt6->ia6t_preferred = 0; 1173 else { 1174 lt6->ia6t_preferred = time_uptime; 1175 lt6->ia6t_preferred += lt6->ia6t_pltime; 1176 } 1177 } 1178 1179 static struct in6_ifaddr * 1180 in6_ifadd(struct nd_prefixctl *pr, int mcast) 1181 { 1182 struct ifnet *ifp = pr->ndpr_ifp; 1183 struct ifaddr *ifa; 1184 struct in6_aliasreq ifra; 1185 struct in6_ifaddr *ia = NULL, *ib = NULL; 1186 int error, plen0; 1187 struct in6_addr *ifid_addr = NULL, mask; 1188 int prefixlen = pr->ndpr_plen; 1189 int updateflags; 1190 char ip6buf[INET6_ADDRSTRLEN]; 1191 1192 in6_prefixlen2mask(&mask, prefixlen); 1193 1194 /* 1195 * find a link-local address (will be interface ID). 1196 * Is it really mandatory? Theoretically, a global or a site-local 1197 * address can be configured without a link-local address, if we 1198 * have a unique interface identifier... 1199 * 1200 * it is not mandatory to have a link-local address, we can generate 1201 * interface identifier on the fly. we do this because: 1202 * (1) it should be the easiest way to find interface identifier. 1203 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1204 * for multiple addresses on a single interface, and possible shortcut 1205 * of DAD. we omitted DAD for this reason in the past. 1206 * (3) a user can prevent autoconfiguration of global address 1207 * by removing link-local address by hand (this is partly because we 1208 * don't have other way to control the use of IPv6 on an interface. 1209 * this has been our design choice - cf. NRL's "ifconfig auto"). 1210 * (4) it is easier to manage when an interface has addresses 1211 * with the same interface identifier, than to have multiple addresses 1212 * with different interface identifiers. 1213 */ 1214 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1215 if (ifa) { 1216 ib = (struct in6_ifaddr *)ifa; 1217 ifid_addr = &ib->ia_addr.sin6_addr; 1218 1219 /* prefixlen + ifidlen must be equal to 128 */ 1220 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1221 if (prefixlen != plen0) { 1222 ifa_free(ifa); 1223 ifid_addr = NULL; 1224 nd6log((LOG_DEBUG, 1225 "%s: wrong prefixlen for %s (prefix=%d ifid=%d)\n", 1226 __func__, if_name(ifp), prefixlen, 128 - plen0)); 1227 } 1228 } 1229 1230 /* No suitable LL address, get the ifid directly */ 1231 if (ifid_addr == NULL) { 1232 struct in6_addr taddr; 1233 ifa = ifa_alloc(sizeof(taddr), M_WAITOK); 1234 if (ifa) { 1235 ib = (struct in6_ifaddr *)ifa; 1236 ifid_addr = &ib->ia_addr.sin6_addr; 1237 if(in6_get_ifid(ifp, NULL, ifid_addr) != 0) { 1238 nd6log((LOG_DEBUG, 1239 "%s: failed to get ifid for %s\n", 1240 __func__, if_name(ifp))); 1241 ifa_free(ifa); 1242 ifid_addr = NULL; 1243 } 1244 } 1245 } 1246 1247 if (ifid_addr == NULL) { 1248 nd6log((LOG_INFO, 1249 "%s: could not determine ifid for %s\n", 1250 __func__, if_name(ifp))); 1251 return NULL; 1252 } 1253 1254 /* make ifaddr */ 1255 in6_prepare_ifra(&ifra, &pr->ndpr_prefix.sin6_addr, &mask); 1256 1257 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, &mask); 1258 /* interface ID */ 1259 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1260 (ifid_addr->s6_addr32[0] & ~mask.s6_addr32[0]); 1261 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1262 (ifid_addr->s6_addr32[1] & ~mask.s6_addr32[1]); 1263 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1264 (ifid_addr->s6_addr32[2] & ~mask.s6_addr32[2]); 1265 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1266 (ifid_addr->s6_addr32[3] & ~mask.s6_addr32[3]); 1267 ifa_free(ifa); 1268 1269 /* lifetimes. */ 1270 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1271 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1272 1273 /* XXX: scope zone ID? */ 1274 1275 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1276 1277 /* 1278 * Make sure that we do not have this address already. This should 1279 * usually not happen, but we can still see this case, e.g., if we 1280 * have manually configured the exact address to be configured. 1281 */ 1282 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 1283 &ifra.ifra_addr.sin6_addr); 1284 if (ifa != NULL) { 1285 ifa_free(ifa); 1286 /* this should be rare enough to make an explicit log */ 1287 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1288 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr)); 1289 return (NULL); 1290 } 1291 1292 /* 1293 * Allocate ifaddr structure, link into chain, etc. 1294 * If we are going to create a new address upon receiving a multicasted 1295 * RA, we need to impose a random delay before starting DAD. 1296 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1297 */ 1298 updateflags = 0; 1299 if (mcast) 1300 updateflags |= IN6_IFAUPDATE_DADDELAY; 1301 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 1302 nd6log((LOG_ERR, 1303 "%s: failed to make ifaddr %s on %s (errno=%d)\n", __func__, 1304 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr), 1305 if_name(ifp), error)); 1306 return (NULL); /* ifaddr must not have been allocated. */ 1307 } 1308 1309 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1310 /* 1311 * XXXRW: Assumption of non-NULLness here might not be true with 1312 * fine-grained locking -- should we validate it? Or just return 1313 * earlier ifa rather than looking it up again? 1314 */ 1315 return (ia); /* this is always non-NULL and referenced. */ 1316 } 1317 1318 static struct nd_prefix * 1319 nd6_prefix_lookup_locked(struct nd_prefixctl *key) 1320 { 1321 struct nd_prefix *search; 1322 1323 ND6_LOCK_ASSERT(); 1324 1325 LIST_FOREACH(search, &V_nd_prefix, ndpr_entry) { 1326 if (key->ndpr_ifp == search->ndpr_ifp && 1327 key->ndpr_plen == search->ndpr_plen && 1328 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 1329 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 1330 nd6_prefix_ref(search); 1331 break; 1332 } 1333 } 1334 return (search); 1335 } 1336 1337 struct nd_prefix * 1338 nd6_prefix_lookup(struct nd_prefixctl *key) 1339 { 1340 struct nd_prefix *search; 1341 1342 ND6_RLOCK(); 1343 search = nd6_prefix_lookup_locked(key); 1344 ND6_RUNLOCK(); 1345 return (search); 1346 } 1347 1348 void 1349 nd6_prefix_ref(struct nd_prefix *pr) 1350 { 1351 1352 refcount_acquire(&pr->ndpr_refcnt); 1353 } 1354 1355 void 1356 nd6_prefix_rele(struct nd_prefix *pr) 1357 { 1358 1359 if (refcount_release(&pr->ndpr_refcnt)) { 1360 KASSERT(LIST_EMPTY(&pr->ndpr_advrtrs), 1361 ("prefix %p has advertising routers", pr)); 1362 free(pr, M_IP6NDP); 1363 } 1364 } 1365 1366 int 1367 nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 1368 struct nd_prefix **newp) 1369 { 1370 struct nd_prefix *new; 1371 char ip6buf[INET6_ADDRSTRLEN]; 1372 int error; 1373 1374 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 1375 if (new == NULL) 1376 return (ENOMEM); 1377 refcount_init(&new->ndpr_refcnt, newp != NULL ? 2 : 1); 1378 new->ndpr_ifp = pr->ndpr_ifp; 1379 new->ndpr_prefix = pr->ndpr_prefix; 1380 new->ndpr_plen = pr->ndpr_plen; 1381 new->ndpr_vltime = pr->ndpr_vltime; 1382 new->ndpr_pltime = pr->ndpr_pltime; 1383 new->ndpr_flags = pr->ndpr_flags; 1384 if ((error = in6_init_prefix_ltimes(new)) != 0) { 1385 free(new, M_IP6NDP); 1386 return (error); 1387 } 1388 new->ndpr_lastupdate = time_uptime; 1389 1390 /* initialization */ 1391 LIST_INIT(&new->ndpr_advrtrs); 1392 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 1393 /* make prefix in the canonical form */ 1394 IN6_MASK_ADDR(&new->ndpr_prefix.sin6_addr, &new->ndpr_mask); 1395 1396 ND6_WLOCK(); 1397 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry); 1398 V_nd6_list_genid++; 1399 ND6_WUNLOCK(); 1400 1401 /* ND_OPT_PI_FLAG_ONLINK processing */ 1402 if (new->ndpr_raf_onlink) { 1403 struct epoch_tracker et; 1404 1405 ND6_ONLINK_LOCK(); 1406 NET_EPOCH_ENTER(et); 1407 if ((error = nd6_prefix_onlink(new)) != 0) { 1408 nd6log((LOG_ERR, "%s: failed to make the prefix %s/%d " 1409 "on-link on %s (errno=%d)\n", __func__, 1410 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1411 pr->ndpr_plen, if_name(pr->ndpr_ifp), error)); 1412 /* proceed anyway. XXX: is it correct? */ 1413 } 1414 NET_EPOCH_EXIT(et); 1415 ND6_ONLINK_UNLOCK(); 1416 } 1417 1418 if (dr != NULL) 1419 pfxrtr_add(new, dr); 1420 if (newp != NULL) 1421 *newp = new; 1422 return (0); 1423 } 1424 1425 /* 1426 * Remove a prefix from the prefix list and optionally stash it in a 1427 * caller-provided list. 1428 * 1429 * The ND6 lock must be held. 1430 */ 1431 void 1432 nd6_prefix_unlink(struct nd_prefix *pr, struct nd_prhead *list) 1433 { 1434 1435 ND6_WLOCK_ASSERT(); 1436 1437 LIST_REMOVE(pr, ndpr_entry); 1438 V_nd6_list_genid++; 1439 if (list != NULL) 1440 LIST_INSERT_HEAD(list, pr, ndpr_entry); 1441 } 1442 1443 /* 1444 * Free an unlinked prefix, first marking it off-link if necessary. 1445 */ 1446 void 1447 nd6_prefix_del(struct nd_prefix *pr) 1448 { 1449 struct nd_pfxrouter *pfr, *next; 1450 int e; 1451 char ip6buf[INET6_ADDRSTRLEN]; 1452 1453 KASSERT(pr->ndpr_addrcnt == 0, 1454 ("prefix %p has referencing addresses", pr)); 1455 ND6_UNLOCK_ASSERT(); 1456 1457 /* 1458 * Though these flags are now meaningless, we'd rather keep the value 1459 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users 1460 * when executing "ndp -p". 1461 */ 1462 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1463 ND6_ONLINK_LOCK(); 1464 if ((e = nd6_prefix_offlink(pr)) != 0) { 1465 nd6log((LOG_ERR, 1466 "%s: failed to make the prefix %s/%d offlink on %s " 1467 "(errno=%d)\n", __func__, 1468 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1469 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1470 /* what should we do? */ 1471 } 1472 ND6_ONLINK_UNLOCK(); 1473 } 1474 1475 /* Release references to routers that have advertised this prefix. */ 1476 ND6_WLOCK(); 1477 LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next) 1478 pfxrtr_del(pfr); 1479 ND6_WUNLOCK(); 1480 1481 nd6_prefix_rele(pr); 1482 1483 pfxlist_onlink_check(); 1484 } 1485 1486 static int 1487 prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr, 1488 struct mbuf *m, int mcast) 1489 { 1490 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 1491 struct ifaddr *ifa; 1492 struct ifnet *ifp = new->ndpr_ifp; 1493 struct nd_prefix *pr; 1494 int error = 0; 1495 int auth; 1496 struct in6_addrlifetime lt6_tmp; 1497 char ip6buf[INET6_ADDRSTRLEN]; 1498 1499 NET_EPOCH_ASSERT(); 1500 1501 auth = 0; 1502 if (m) { 1503 /* 1504 * Authenticity for NA consists authentication for 1505 * both IP header and IP datagrams, doesn't it ? 1506 */ 1507 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1508 auth = ((m->m_flags & M_AUTHIPHDR) && 1509 (m->m_flags & M_AUTHIPDGM)); 1510 #endif 1511 } 1512 1513 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1514 /* 1515 * nd6_prefix_lookup() ensures that pr and new have the same 1516 * prefix on a same interface. 1517 */ 1518 1519 /* 1520 * Update prefix information. Note that the on-link (L) bit 1521 * and the autonomous (A) bit should NOT be changed from 1 1522 * to 0. 1523 */ 1524 if (new->ndpr_raf_onlink == 1) 1525 pr->ndpr_raf_onlink = 1; 1526 if (new->ndpr_raf_auto == 1) 1527 pr->ndpr_raf_auto = 1; 1528 if (new->ndpr_raf_onlink) { 1529 pr->ndpr_vltime = new->ndpr_vltime; 1530 pr->ndpr_pltime = new->ndpr_pltime; 1531 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1532 pr->ndpr_lastupdate = time_uptime; 1533 } 1534 1535 if (new->ndpr_raf_onlink && 1536 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1537 ND6_ONLINK_LOCK(); 1538 if ((error = nd6_prefix_onlink(pr)) != 0) { 1539 nd6log((LOG_ERR, 1540 "%s: failed to make the prefix %s/%d " 1541 "on-link on %s (errno=%d)\n", __func__, 1542 ip6_sprintf(ip6buf, 1543 &pr->ndpr_prefix.sin6_addr), 1544 pr->ndpr_plen, if_name(pr->ndpr_ifp), 1545 error)); 1546 /* proceed anyway. XXX: is it correct? */ 1547 } 1548 ND6_ONLINK_UNLOCK(); 1549 } 1550 1551 if (dr != NULL) 1552 pfxrtr_add(pr, dr); 1553 } else { 1554 if (new->ndpr_vltime == 0) 1555 goto end; 1556 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1557 goto end; 1558 1559 error = nd6_prelist_add(new, dr, &pr); 1560 if (error != 0) { 1561 nd6log((LOG_NOTICE, "%s: nd6_prelist_add() failed for " 1562 "the prefix %s/%d on %s (errno=%d)\n", __func__, 1563 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr), 1564 new->ndpr_plen, if_name(new->ndpr_ifp), error)); 1565 goto end; /* we should just give up in this case. */ 1566 } 1567 1568 /* 1569 * XXX: from the ND point of view, we can ignore a prefix 1570 * with the on-link bit being zero. However, we need a 1571 * prefix structure for references from autoconfigured 1572 * addresses. Thus, we explicitly make sure that the prefix 1573 * itself expires now. 1574 */ 1575 if (pr->ndpr_raf_onlink == 0) { 1576 pr->ndpr_vltime = 0; 1577 pr->ndpr_pltime = 0; 1578 in6_init_prefix_ltimes(pr); 1579 } 1580 } 1581 1582 /* 1583 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1584 * Note that pr must be non NULL at this point. 1585 */ 1586 1587 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1588 if (!new->ndpr_raf_auto) 1589 goto end; 1590 1591 /* 1592 * 5.5.3 (b). the link-local prefix should have been ignored in 1593 * nd6_ra_input. 1594 */ 1595 1596 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1597 if (new->ndpr_pltime > new->ndpr_vltime) { 1598 error = EINVAL; /* XXX: won't be used */ 1599 goto end; 1600 } 1601 1602 /* 1603 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1604 * an address configured by stateless autoconfiguration already in the 1605 * list of addresses associated with the interface, and the Valid 1606 * Lifetime is not 0, form an address. We first check if we have 1607 * a matching prefix. 1608 * Note: we apply a clarification in rfc2462bis-02 here. We only 1609 * consider autoconfigured addresses while RFC2462 simply said 1610 * "address". 1611 */ 1612 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1613 struct in6_ifaddr *ifa6; 1614 u_int32_t remaininglifetime; 1615 1616 if (ifa->ifa_addr->sa_family != AF_INET6) 1617 continue; 1618 1619 ifa6 = (struct in6_ifaddr *)ifa; 1620 1621 /* 1622 * We only consider autoconfigured addresses as per rfc2462bis. 1623 */ 1624 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1625 continue; 1626 1627 /* 1628 * Spec is not clear here, but I believe we should concentrate 1629 * on unicast (i.e. not anycast) addresses. 1630 * XXX: other ia6_flags? detached or duplicated? 1631 */ 1632 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1633 continue; 1634 1635 /* 1636 * Ignore the address if it is not associated with a prefix 1637 * or is associated with a prefix that is different from this 1638 * one. (pr is never NULL here) 1639 */ 1640 if (ifa6->ia6_ndpr != pr) 1641 continue; 1642 1643 if (ia6_match == NULL) /* remember the first one */ 1644 ia6_match = ifa6; 1645 1646 /* 1647 * An already autoconfigured address matched. Now that we 1648 * are sure there is at least one matched address, we can 1649 * proceed to 5.5.3. (e): update the lifetimes according to the 1650 * "two hours" rule and the privacy extension. 1651 * We apply some clarifications in rfc2462bis: 1652 * - use remaininglifetime instead of storedlifetime as a 1653 * variable name 1654 * - remove the dead code in the "two-hour" rule 1655 */ 1656 #define TWOHOUR (120*60) 1657 lt6_tmp = ifa6->ia6_lifetime; 1658 1659 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1660 remaininglifetime = ND6_INFINITE_LIFETIME; 1661 else if (time_uptime - ifa6->ia6_updatetime > 1662 lt6_tmp.ia6t_vltime) { 1663 /* 1664 * The case of "invalid" address. We should usually 1665 * not see this case. 1666 */ 1667 remaininglifetime = 0; 1668 } else 1669 remaininglifetime = lt6_tmp.ia6t_vltime - 1670 (time_uptime - ifa6->ia6_updatetime); 1671 1672 /* when not updating, keep the current stored lifetime. */ 1673 lt6_tmp.ia6t_vltime = remaininglifetime; 1674 1675 if (TWOHOUR < new->ndpr_vltime || 1676 remaininglifetime < new->ndpr_vltime) { 1677 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1678 } else if (remaininglifetime <= TWOHOUR) { 1679 if (auth) { 1680 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1681 } 1682 } else { 1683 /* 1684 * new->ndpr_vltime <= TWOHOUR && 1685 * TWOHOUR < remaininglifetime 1686 */ 1687 lt6_tmp.ia6t_vltime = TWOHOUR; 1688 } 1689 1690 /* The 2 hour rule is not imposed for preferred lifetime. */ 1691 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1692 1693 in6_init_address_ltimes(pr, <6_tmp); 1694 1695 /* 1696 * We need to treat lifetimes for temporary addresses 1697 * differently, according to 1698 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1699 * we only update the lifetimes when they are in the maximum 1700 * intervals. 1701 */ 1702 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1703 u_int32_t maxvltime, maxpltime; 1704 1705 if (V_ip6_temp_valid_lifetime > 1706 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1707 V_ip6_desync_factor)) { 1708 maxvltime = V_ip6_temp_valid_lifetime - 1709 (time_uptime - ifa6->ia6_createtime) - 1710 V_ip6_desync_factor; 1711 } else 1712 maxvltime = 0; 1713 if (V_ip6_temp_preferred_lifetime > 1714 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1715 V_ip6_desync_factor)) { 1716 maxpltime = V_ip6_temp_preferred_lifetime - 1717 (time_uptime - ifa6->ia6_createtime) - 1718 V_ip6_desync_factor; 1719 } else 1720 maxpltime = 0; 1721 1722 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1723 lt6_tmp.ia6t_vltime > maxvltime) { 1724 lt6_tmp.ia6t_vltime = maxvltime; 1725 } 1726 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1727 lt6_tmp.ia6t_pltime > maxpltime) { 1728 lt6_tmp.ia6t_pltime = maxpltime; 1729 } 1730 } 1731 ifa6->ia6_lifetime = lt6_tmp; 1732 ifa6->ia6_updatetime = time_uptime; 1733 } 1734 if (ia6_match == NULL && new->ndpr_vltime) { 1735 int ifidlen; 1736 1737 /* 1738 * 5.5.3 (d) (continued) 1739 * No address matched and the valid lifetime is non-zero. 1740 * Create a new address. 1741 */ 1742 1743 /* 1744 * Prefix Length check: 1745 * If the sum of the prefix length and interface identifier 1746 * length does not equal 128 bits, the Prefix Information 1747 * option MUST be ignored. The length of the interface 1748 * identifier is defined in a separate link-type specific 1749 * document. 1750 */ 1751 ifidlen = in6_if2idlen(ifp); 1752 if (ifidlen < 0) { 1753 /* this should not happen, so we always log it. */ 1754 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1755 if_name(ifp)); 1756 goto end; 1757 } 1758 if (ifidlen + pr->ndpr_plen != 128) { 1759 nd6log((LOG_INFO, 1760 "%s: invalid prefixlen %d for %s, ignored\n", 1761 __func__, pr->ndpr_plen, if_name(ifp))); 1762 goto end; 1763 } 1764 1765 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1766 /* 1767 * note that we should use pr (not new) for reference. 1768 */ 1769 pr->ndpr_addrcnt++; 1770 ia6->ia6_ndpr = pr; 1771 1772 /* 1773 * RFC 3041 3.3 (2). 1774 * When a new public address is created as described 1775 * in RFC2462, also create a new temporary address. 1776 * 1777 * RFC 3041 3.5. 1778 * When an interface connects to a new link, a new 1779 * randomized interface identifier should be generated 1780 * immediately together with a new set of temporary 1781 * addresses. Thus, we specifiy 1 as the 2nd arg of 1782 * in6_tmpifadd(). 1783 */ 1784 if (V_ip6_use_tempaddr) { 1785 int e; 1786 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1787 nd6log((LOG_NOTICE, "%s: failed to " 1788 "create a temporary address " 1789 "(errno=%d)\n", __func__, e)); 1790 } 1791 } 1792 ifa_free(&ia6->ia_ifa); 1793 1794 /* 1795 * A newly added address might affect the status 1796 * of other addresses, so we check and update it. 1797 * XXX: what if address duplication happens? 1798 */ 1799 pfxlist_onlink_check(); 1800 } else { 1801 /* just set an error. do not bark here. */ 1802 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1803 } 1804 } 1805 1806 end: 1807 if (pr != NULL) 1808 nd6_prefix_rele(pr); 1809 return (error); 1810 } 1811 1812 /* 1813 * A supplement function used in the on-link detection below; 1814 * detect if a given prefix has a (probably) reachable advertising router. 1815 * XXX: lengthy function name... 1816 */ 1817 static struct nd_pfxrouter * 1818 find_pfxlist_reachable_router(struct nd_prefix *pr) 1819 { 1820 struct epoch_tracker et; 1821 struct nd_pfxrouter *pfxrtr; 1822 1823 ND6_LOCK_ASSERT(); 1824 1825 NET_EPOCH_ENTER(et); 1826 LIST_FOREACH(pfxrtr, &pr->ndpr_advrtrs, pfr_entry) { 1827 if (is_dr_reachable(pfxrtr->router)) 1828 break; 1829 } 1830 NET_EPOCH_EXIT(et); 1831 return (pfxrtr); 1832 } 1833 1834 /* 1835 * Check if each prefix in the prefix list has at least one available router 1836 * that advertised the prefix (a router is "available" if its neighbor cache 1837 * entry is reachable or probably reachable). 1838 * If the check fails, the prefix may be off-link, because, for example, 1839 * we have moved from the network but the lifetime of the prefix has not 1840 * expired yet. So we should not use the prefix if there is another prefix 1841 * that has an available router. 1842 * But, if there is no prefix that has an available router, we still regard 1843 * all the prefixes as on-link. This is because we can't tell if all the 1844 * routers are simply dead or if we really moved from the network and there 1845 * is no router around us. 1846 */ 1847 void 1848 pfxlist_onlink_check(void) 1849 { 1850 struct nd_prefix *pr; 1851 struct in6_ifaddr *ifa; 1852 struct nd_defrouter *dr; 1853 struct nd_pfxrouter *pfxrtr = NULL; 1854 struct rm_priotracker in6_ifa_tracker; 1855 uint64_t genid; 1856 uint32_t flags; 1857 1858 ND6_ONLINK_LOCK(); 1859 ND6_RLOCK(); 1860 1861 /* 1862 * Check if there is a prefix that has a reachable advertising 1863 * router. 1864 */ 1865 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1866 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1867 break; 1868 } 1869 1870 /* 1871 * If we have no such prefix, check whether we still have a router 1872 * that does not advertise any prefixes. 1873 */ 1874 if (pr == NULL) { 1875 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 1876 struct nd_prefix *pr0; 1877 1878 LIST_FOREACH(pr0, &V_nd_prefix, ndpr_entry) { 1879 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1880 break; 1881 } 1882 if (pfxrtr != NULL) 1883 break; 1884 } 1885 } 1886 if (pr != NULL || (!TAILQ_EMPTY(&V_nd6_defrouter) && pfxrtr == NULL)) { 1887 /* 1888 * There is at least one prefix that has a reachable router, 1889 * or at least a router which probably does not advertise 1890 * any prefixes. The latter would be the case when we move 1891 * to a new link where we have a router that does not provide 1892 * prefixes and we configure an address by hand. 1893 * Detach prefixes which have no reachable advertising 1894 * router, and attach other prefixes. 1895 */ 1896 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1897 /* XXX: a link-local prefix should never be detached */ 1898 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1899 pr->ndpr_raf_onlink == 0 || 1900 pr->ndpr_raf_auto == 0) 1901 continue; 1902 1903 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1904 find_pfxlist_reachable_router(pr) == NULL) 1905 pr->ndpr_stateflags |= NDPRF_DETACHED; 1906 else if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1907 find_pfxlist_reachable_router(pr) != NULL) 1908 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1909 } 1910 } else { 1911 /* there is no prefix that has a reachable router */ 1912 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1913 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1914 pr->ndpr_raf_onlink == 0 || 1915 pr->ndpr_raf_auto == 0) 1916 continue; 1917 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1918 } 1919 } 1920 1921 /* 1922 * Remove each interface route associated with a (just) detached 1923 * prefix, and reinstall the interface route for a (just) attached 1924 * prefix. Note that all attempt of reinstallation does not 1925 * necessarily success, when a same prefix is shared among multiple 1926 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1927 * so we don't have to care about them. 1928 */ 1929 restart: 1930 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1931 char ip6buf[INET6_ADDRSTRLEN]; 1932 int e; 1933 1934 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1935 pr->ndpr_raf_onlink == 0 || 1936 pr->ndpr_raf_auto == 0) 1937 continue; 1938 1939 flags = pr->ndpr_stateflags & (NDPRF_DETACHED | NDPRF_ONLINK); 1940 if (flags == 0 || flags == (NDPRF_DETACHED | NDPRF_ONLINK)) { 1941 genid = V_nd6_list_genid; 1942 ND6_RUNLOCK(); 1943 if ((flags & NDPRF_ONLINK) != 0 && 1944 (e = nd6_prefix_offlink(pr)) != 0) { 1945 nd6log((LOG_ERR, 1946 "%s: failed to make %s/%d offlink " 1947 "(errno=%d)\n", __func__, 1948 ip6_sprintf(ip6buf, 1949 &pr->ndpr_prefix.sin6_addr), 1950 pr->ndpr_plen, e)); 1951 } else if ((flags & NDPRF_ONLINK) == 0 && 1952 (e = nd6_prefix_onlink(pr)) != 0) { 1953 nd6log((LOG_ERR, 1954 "%s: failed to make %s/%d onlink " 1955 "(errno=%d)\n", __func__, 1956 ip6_sprintf(ip6buf, 1957 &pr->ndpr_prefix.sin6_addr), 1958 pr->ndpr_plen, e)); 1959 } 1960 ND6_RLOCK(); 1961 if (genid != V_nd6_list_genid) 1962 goto restart; 1963 } 1964 } 1965 1966 /* 1967 * Changes on the prefix status might affect address status as well. 1968 * Make sure that all addresses derived from an attached prefix are 1969 * attached, and that all addresses derived from a detached prefix are 1970 * detached. Note, however, that a manually configured address should 1971 * always be attached. 1972 * The precise detection logic is same as the one for prefixes. 1973 */ 1974 IN6_IFADDR_RLOCK(&in6_ifa_tracker); 1975 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1976 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1977 continue; 1978 1979 if (ifa->ia6_ndpr == NULL) { 1980 /* 1981 * This can happen when we first configure the address 1982 * (i.e. the address exists, but the prefix does not). 1983 * XXX: complicated relationships... 1984 */ 1985 continue; 1986 } 1987 1988 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1989 break; 1990 } 1991 if (ifa) { 1992 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1993 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1994 continue; 1995 1996 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1997 continue; 1998 1999 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 2000 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 2001 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 2002 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 2003 nd6_dad_start((struct ifaddr *)ifa, 0); 2004 } 2005 } else { 2006 ifa->ia6_flags |= IN6_IFF_DETACHED; 2007 } 2008 } 2009 } else { 2010 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 2011 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 2012 continue; 2013 2014 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 2015 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 2016 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 2017 /* Do we need a delay in this case? */ 2018 nd6_dad_start((struct ifaddr *)ifa, 0); 2019 } 2020 } 2021 } 2022 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker); 2023 ND6_RUNLOCK(); 2024 ND6_ONLINK_UNLOCK(); 2025 } 2026 2027 /* 2028 * Add or remove interface route specified by @dst, @netmask and @ifp. 2029 * ifa can be NULL. 2030 * Returns 0 on success 2031 */ 2032 static int 2033 nd6_prefix_rtrequest(uint32_t fibnum, int cmd, struct sockaddr_in6 *dst, 2034 struct sockaddr_in6 *netmask, struct ifnet *ifp, struct ifaddr *ifa) 2035 { 2036 struct epoch_tracker et; 2037 int error; 2038 2039 /* Prepare gateway */ 2040 struct sockaddr_dl_short sdl = { 2041 .sdl_family = AF_LINK, 2042 .sdl_len = sizeof(struct sockaddr_dl_short), 2043 .sdl_type = ifp->if_type, 2044 .sdl_index = ifp->if_index, 2045 }; 2046 2047 struct rt_addrinfo info = { 2048 .rti_ifa = ifa, 2049 .rti_ifp = ifp, 2050 .rti_flags = RTF_PINNED | ((netmask != NULL) ? 0 : RTF_HOST), 2051 .rti_info = { 2052 [RTAX_DST] = (struct sockaddr *)dst, 2053 [RTAX_NETMASK] = (struct sockaddr *)netmask, 2054 [RTAX_GATEWAY] = (struct sockaddr *)&sdl, 2055 }, 2056 }; 2057 /* Don't set additional per-gw filters on removal */ 2058 2059 NET_EPOCH_ENTER(et); 2060 error = rib_handle_ifaddr_info(fibnum, cmd, &info); 2061 NET_EPOCH_EXIT(et); 2062 return (error); 2063 } 2064 2065 static int 2066 nd6_prefix_onlink_rtrequest(struct nd_prefix *pr, struct ifaddr *ifa) 2067 { 2068 int error; 2069 2070 struct sockaddr_in6 mask6 = { 2071 .sin6_family = AF_INET6, 2072 .sin6_len = sizeof(struct sockaddr_in6), 2073 .sin6_addr = pr->ndpr_mask, 2074 }; 2075 struct sockaddr_in6 *pmask6 = (pr->ndpr_plen != 128) ? &mask6 : NULL; 2076 2077 error = nd6_prefix_rtrequest(pr->ndpr_ifp->if_fib, RTM_ADD, 2078 &pr->ndpr_prefix, pmask6, pr->ndpr_ifp, ifa); 2079 if (error == 0) 2080 pr->ndpr_stateflags |= NDPRF_ONLINK; 2081 2082 return (error); 2083 } 2084 2085 static int 2086 nd6_prefix_onlink(struct nd_prefix *pr) 2087 { 2088 struct epoch_tracker et; 2089 struct ifaddr *ifa; 2090 struct ifnet *ifp = pr->ndpr_ifp; 2091 struct nd_prefix *opr; 2092 char ip6buf[INET6_ADDRSTRLEN]; 2093 int error; 2094 2095 ND6_ONLINK_LOCK_ASSERT(); 2096 ND6_UNLOCK_ASSERT(); 2097 2098 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) 2099 return (EEXIST); 2100 2101 /* 2102 * Add the interface route associated with the prefix. Before 2103 * installing the route, check if there's the same prefix on another 2104 * interface, and the prefix has already installed the interface route. 2105 * Although such a configuration is expected to be rare, we explicitly 2106 * allow it. 2107 */ 2108 ND6_RLOCK(); 2109 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 2110 if (opr == pr) 2111 continue; 2112 2113 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 2114 continue; 2115 2116 if (!V_rt_add_addr_allfibs && 2117 opr->ndpr_ifp->if_fib != pr->ndpr_ifp->if_fib) 2118 continue; 2119 2120 if (opr->ndpr_plen == pr->ndpr_plen && 2121 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 2122 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 2123 ND6_RUNLOCK(); 2124 return (0); 2125 } 2126 } 2127 ND6_RUNLOCK(); 2128 2129 /* 2130 * We prefer link-local addresses as the associated interface address. 2131 */ 2132 /* search for a link-local addr */ 2133 NET_EPOCH_ENTER(et); 2134 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 2135 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 2136 if (ifa == NULL) { 2137 /* XXX: freebsd does not have ifa_ifwithaf */ 2138 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 2139 if (ifa->ifa_addr->sa_family == AF_INET6) { 2140 ifa_ref(ifa); 2141 break; 2142 } 2143 } 2144 /* should we care about ia6_flags? */ 2145 } 2146 if (ifa == NULL) { 2147 /* 2148 * This can still happen, when, for example, we receive an RA 2149 * containing a prefix with the L bit set and the A bit clear, 2150 * after removing all IPv6 addresses on the receiving 2151 * interface. This should, of course, be rare though. 2152 */ 2153 nd6log((LOG_NOTICE, 2154 "%s: failed to find any ifaddr to add route for a " 2155 "prefix(%s/%d) on %s\n", __func__, 2156 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 2157 pr->ndpr_plen, if_name(ifp))); 2158 error = 0; 2159 } else { 2160 error = nd6_prefix_onlink_rtrequest(pr, ifa); 2161 ifa_free(ifa); 2162 } 2163 NET_EPOCH_EXIT(et); 2164 2165 return (error); 2166 } 2167 2168 int 2169 nd6_prefix_offlink(struct nd_prefix *pr) 2170 { 2171 int error = 0; 2172 struct ifnet *ifp = pr->ndpr_ifp; 2173 struct nd_prefix *opr; 2174 char ip6buf[INET6_ADDRSTRLEN]; 2175 uint64_t genid; 2176 int a_failure; 2177 2178 ND6_ONLINK_LOCK_ASSERT(); 2179 ND6_UNLOCK_ASSERT(); 2180 2181 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) 2182 return (EEXIST); 2183 2184 struct sockaddr_in6 mask6 = { 2185 .sin6_family = AF_INET6, 2186 .sin6_len = sizeof(struct sockaddr_in6), 2187 .sin6_addr = pr->ndpr_mask, 2188 }; 2189 struct sockaddr_in6 *pmask6 = (pr->ndpr_plen != 128) ? &mask6 : NULL; 2190 2191 error = nd6_prefix_rtrequest(ifp->if_fib, RTM_DELETE, 2192 &pr->ndpr_prefix, pmask6, ifp, NULL); 2193 2194 a_failure = 1; 2195 if (error == 0) { 2196 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 2197 2198 /* 2199 * There might be the same prefix on another interface, 2200 * the prefix which could not be on-link just because we have 2201 * the interface route (see comments in nd6_prefix_onlink). 2202 * If there's one, try to make the prefix on-link on the 2203 * interface. 2204 */ 2205 ND6_RLOCK(); 2206 restart: 2207 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 2208 /* 2209 * KAME specific: detached prefixes should not be 2210 * on-link. 2211 */ 2212 if (opr == pr || (opr->ndpr_stateflags & 2213 (NDPRF_ONLINK | NDPRF_DETACHED)) != 0) 2214 continue; 2215 2216 if (opr->ndpr_plen == pr->ndpr_plen && 2217 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 2218 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 2219 int e; 2220 2221 genid = V_nd6_list_genid; 2222 ND6_RUNLOCK(); 2223 if ((e = nd6_prefix_onlink(opr)) != 0) { 2224 nd6log((LOG_ERR, 2225 "%s: failed to recover a prefix " 2226 "%s/%d from %s to %s (errno=%d)\n", 2227 __func__, ip6_sprintf(ip6buf, 2228 &opr->ndpr_prefix.sin6_addr), 2229 opr->ndpr_plen, if_name(ifp), 2230 if_name(opr->ndpr_ifp), e)); 2231 } else 2232 a_failure = 0; 2233 ND6_RLOCK(); 2234 if (genid != V_nd6_list_genid) 2235 goto restart; 2236 } 2237 } 2238 ND6_RUNLOCK(); 2239 } else { 2240 /* XXX: can we still set the NDPRF_ONLINK flag? */ 2241 nd6log((LOG_ERR, 2242 "%s: failed to delete route: %s/%d on %s (errno=%d)\n", 2243 __func__, ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 2244 pr->ndpr_plen, if_name(ifp), error)); 2245 } 2246 2247 if (a_failure) 2248 lltable_prefix_free(AF_INET6, 2249 (struct sockaddr *)&pr->ndpr_prefix, 2250 (struct sockaddr *)&mask6, LLE_STATIC); 2251 2252 return (error); 2253 } 2254 2255 /* 2256 * Get a randomized interface identifier for a temporary address 2257 * Based on RFC 8981, Section 3.3.1. 2258 */ 2259 static int 2260 in6_get_tmp_ifid(struct in6_aliasreq *ifra) 2261 { 2262 struct in6_addr *addr; 2263 2264 if(!is_random_seeded()){ 2265 return 1; 2266 } 2267 2268 addr = &(ifra->ifra_addr.sin6_addr); 2269 regen: 2270 ifra->ifra_addr.sin6_addr.s6_addr32[2] |= 2271 (arc4random() & ~(ifra->ifra_prefixmask.sin6_addr.s6_addr32[2])); 2272 ifra->ifra_addr.sin6_addr.s6_addr32[3] |= 2273 (arc4random() & ~(ifra->ifra_prefixmask.sin6_addr.s6_addr32[3])); 2274 2275 /* 2276 * Check if generated address is not inappropriate: 2277 * 2278 * - Reserved IPv6 Interface aIdentifers 2279 * (https://www.iana.org/assignments/ipv6-interface-ids/) 2280 */ 2281 2282 /* Subnet-router anycast: 0000:0000:0000:0000 */ 2283 if (!(addr->s6_addr32[2] | addr->s6_addr32[3])) 2284 goto regen; 2285 2286 /* 2287 * IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212 2288 * Proxy Mobile IPv6: 0200:5EFF:FE00:5213 2289 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF 2290 */ 2291 if (ntohl(addr->s6_addr32[2]) == 0x02005eff && 2292 (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000) 2293 goto regen; 2294 2295 /* Reserved subnet anycast addresses */ 2296 if (ntohl(addr->s6_addr32[2]) == 0xfdffffff && 2297 ntohl(addr->s6_addr32[3]) >= 0Xffffff80) 2298 goto regen; 2299 2300 return 0; 2301 } 2302 2303 /* 2304 * ia0 - corresponding public address 2305 */ 2306 int 2307 in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay) 2308 { 2309 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 2310 struct in6_ifaddr *newia; 2311 struct in6_aliasreq ifra; 2312 int error; 2313 int trylimit = 3; /* XXX: adhoc value */ 2314 int updateflags; 2315 time_t vltime0, pltime0; 2316 2317 in6_prepare_ifra(&ifra, &ia0->ia_addr.sin6_addr, 2318 &ia0->ia_prefixmask.sin6_addr); 2319 2320 ifra.ifra_addr = ia0->ia_addr; /* XXX: do we need this ? */ 2321 /* clear the old IFID */ 2322 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, 2323 &ifra.ifra_prefixmask.sin6_addr); 2324 2325 again: 2326 if (in6_get_tmp_ifid(&ifra) != 0) { 2327 nd6log((LOG_NOTICE, "%s: failed to find a good random IFID\n", 2328 __func__)); 2329 return (EINVAL); 2330 } 2331 2332 /* 2333 * in6_get_tmpifid() quite likely provided a unique interface ID. 2334 * However, we may still have a chance to see collision, because 2335 * there may be a time lag between generation of the ID and generation 2336 * of the address. So, we'll do one more sanity check. 2337 */ 2338 2339 if (in6_localip(&ifra.ifra_addr.sin6_addr) != 0) { 2340 if (trylimit-- > 0) { 2341 forcegen = 1; 2342 goto again; 2343 } 2344 2345 /* Give up. Something strange should have happened. */ 2346 nd6log((LOG_NOTICE, "%s: failed to find a unique random IFID\n", 2347 __func__)); 2348 return (EEXIST); 2349 } 2350 2351 /* 2352 * The Valid Lifetime is the lower of the Valid Lifetime of the 2353 * public address or TEMP_VALID_LIFETIME. 2354 * The Preferred Lifetime is the lower of the Preferred Lifetime 2355 * of the public address or TEMP_PREFERRED_LIFETIME - 2356 * DESYNC_FACTOR. 2357 */ 2358 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 2359 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 2360 (ia0->ia6_lifetime.ia6t_vltime - 2361 (time_uptime - ia0->ia6_updatetime)); 2362 if (vltime0 > V_ip6_temp_valid_lifetime) 2363 vltime0 = V_ip6_temp_valid_lifetime; 2364 } else 2365 vltime0 = V_ip6_temp_valid_lifetime; 2366 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 2367 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 2368 (ia0->ia6_lifetime.ia6t_pltime - 2369 (time_uptime - ia0->ia6_updatetime)); 2370 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){ 2371 pltime0 = V_ip6_temp_preferred_lifetime - 2372 V_ip6_desync_factor; 2373 } 2374 } else 2375 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor; 2376 ifra.ifra_lifetime.ia6t_vltime = vltime0; 2377 ifra.ifra_lifetime.ia6t_pltime = pltime0; 2378 2379 /* 2380 * A temporary address is created only if this calculated Preferred 2381 * Lifetime is greater than REGEN_ADVANCE time units. 2382 */ 2383 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance) 2384 return (0); 2385 2386 /* XXX: scope zone ID? */ 2387 2388 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2389 2390 /* allocate ifaddr structure, link into chain, etc. */ 2391 updateflags = 0; 2392 if (delay) 2393 updateflags |= IN6_IFAUPDATE_DADDELAY; 2394 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 2395 return (error); 2396 2397 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2398 if (newia == NULL) { /* XXX: can it happen? */ 2399 nd6log((LOG_ERR, 2400 "%s: ifa update succeeded, but we got no ifaddr\n", 2401 __func__)); 2402 return (EINVAL); /* XXX */ 2403 } 2404 newia->ia6_ndpr = ia0->ia6_ndpr; 2405 newia->ia6_ndpr->ndpr_addrcnt++; 2406 ifa_free(&newia->ia_ifa); 2407 2408 /* 2409 * A newly added address might affect the status of other addresses. 2410 * XXX: when the temporary address is generated with a new public 2411 * address, the onlink check is redundant. However, it would be safe 2412 * to do the check explicitly everywhere a new address is generated, 2413 * and, in fact, we surely need the check when we create a new 2414 * temporary address due to deprecation of an old temporary address. 2415 */ 2416 pfxlist_onlink_check(); 2417 2418 return (0); 2419 } 2420 2421 static int 2422 rt6_deleteroute(const struct rtentry *rt, const struct nhop_object *nh, 2423 void *arg) 2424 { 2425 struct in6_addr *gate = (struct in6_addr *)arg; 2426 int nh_rt_flags; 2427 2428 if (nh->gw_sa.sa_family != AF_INET6) 2429 return (0); 2430 2431 if (!IN6_ARE_ADDR_EQUAL(gate, &nh->gw6_sa.sin6_addr)) { 2432 return (0); 2433 } 2434 2435 /* 2436 * Do not delete a static route. 2437 * XXX: this seems to be a bit ad-hoc. Should we consider the 2438 * 'cloned' bit instead? 2439 */ 2440 nh_rt_flags = nhop_get_rtflags(nh); 2441 if ((nh_rt_flags & RTF_STATIC) != 0) 2442 return (0); 2443 2444 /* 2445 * We delete only host route. This means, in particular, we don't 2446 * delete default route. 2447 */ 2448 if ((nh_rt_flags & RTF_HOST) == 0) 2449 return (0); 2450 2451 return (1); 2452 #undef SIN6 2453 } 2454 2455 /* 2456 * Delete all the routing table entries that use the specified gateway. 2457 * XXX: this function causes search through all entries of routing table, so 2458 * it shouldn't be called when acting as a router. 2459 */ 2460 void 2461 rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2462 { 2463 2464 /* We'll care only link-local addresses */ 2465 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) 2466 return; 2467 2468 /* XXX Do we really need to walk any but the default FIB? */ 2469 rib_foreach_table_walk_del(AF_INET6, rt6_deleteroute, (void *)gateway); 2470 } 2471 2472 int 2473 nd6_setdefaultiface(int ifindex) 2474 { 2475 2476 if (V_nd6_defifindex != ifindex) { 2477 V_nd6_defifindex = ifindex; 2478 if (V_nd6_defifindex != 0) { 2479 struct epoch_tracker et; 2480 2481 /* 2482 * XXXGL: this function should use ifnet_byindex_ref! 2483 */ 2484 NET_EPOCH_ENTER(et); 2485 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex); 2486 NET_EPOCH_EXIT(et); 2487 if (V_nd6_defifp == NULL) 2488 return (EINVAL); 2489 } else 2490 V_nd6_defifp = NULL; 2491 2492 /* 2493 * Our current implementation assumes one-to-one mapping between 2494 * interfaces and links, so it would be natural to use the 2495 * default interface as the default link. 2496 */ 2497 scope6_setdefault(V_nd6_defifp); 2498 } 2499 2500 return (0); 2501 } 2502 2503 bool 2504 nd6_defrouter_list_empty(void) 2505 { 2506 2507 return (TAILQ_EMPTY(&V_nd6_defrouter)); 2508 } 2509 2510 void 2511 nd6_defrouter_timer(void) 2512 { 2513 struct nd_defrouter *dr, *ndr; 2514 struct nd6_drhead drq; 2515 2516 TAILQ_INIT(&drq); 2517 2518 ND6_WLOCK(); 2519 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) 2520 if (dr->expire && dr->expire < time_uptime) 2521 defrouter_unlink(dr, &drq); 2522 ND6_WUNLOCK(); 2523 2524 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2525 TAILQ_REMOVE(&drq, dr, dr_entry); 2526 defrouter_del(dr); 2527 } 2528 } 2529 2530 /* 2531 * Nuke default router list entries toward ifp. 2532 * We defer removal of default router list entries that is installed in the 2533 * routing table, in order to keep additional side effects as small as possible. 2534 */ 2535 void 2536 nd6_defrouter_purge(struct ifnet *ifp) 2537 { 2538 struct nd_defrouter *dr, *ndr; 2539 struct nd6_drhead drq; 2540 2541 TAILQ_INIT(&drq); 2542 2543 ND6_WLOCK(); 2544 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) { 2545 if (dr->installed) 2546 continue; 2547 if (dr->ifp == ifp) 2548 defrouter_unlink(dr, &drq); 2549 } 2550 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) { 2551 if (!dr->installed) 2552 continue; 2553 if (dr->ifp == ifp) 2554 defrouter_unlink(dr, &drq); 2555 } 2556 ND6_WUNLOCK(); 2557 2558 /* Delete the unlinked router objects. */ 2559 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2560 TAILQ_REMOVE(&drq, dr, dr_entry); 2561 defrouter_del(dr); 2562 } 2563 } 2564 2565 void 2566 nd6_defrouter_flush_all(void) 2567 { 2568 struct nd_defrouter *dr; 2569 struct nd6_drhead drq; 2570 2571 TAILQ_INIT(&drq); 2572 2573 ND6_WLOCK(); 2574 while ((dr = TAILQ_FIRST(&V_nd6_defrouter)) != NULL) 2575 defrouter_unlink(dr, &drq); 2576 ND6_WUNLOCK(); 2577 2578 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2579 TAILQ_REMOVE(&drq, dr, dr_entry); 2580 defrouter_del(dr); 2581 } 2582 } 2583 2584 void 2585 nd6_defrouter_init(void) 2586 { 2587 2588 TAILQ_INIT(&V_nd6_defrouter); 2589 } 2590 2591 static int 2592 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS) 2593 { 2594 struct in6_defrouter d; 2595 struct nd_defrouter *dr; 2596 int error; 2597 2598 if (req->newptr != NULL) 2599 return (EPERM); 2600 2601 error = sysctl_wire_old_buffer(req, 0); 2602 if (error != 0) 2603 return (error); 2604 2605 bzero(&d, sizeof(d)); 2606 d.rtaddr.sin6_family = AF_INET6; 2607 d.rtaddr.sin6_len = sizeof(d.rtaddr); 2608 2609 ND6_RLOCK(); 2610 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 2611 d.rtaddr.sin6_addr = dr->rtaddr; 2612 error = sa6_recoverscope(&d.rtaddr); 2613 if (error != 0) 2614 break; 2615 d.flags = dr->raflags; 2616 d.rtlifetime = dr->rtlifetime; 2617 d.expire = dr->expire + (time_second - time_uptime); 2618 d.if_index = dr->ifp->if_index; 2619 error = SYSCTL_OUT(req, &d, sizeof(d)); 2620 if (error != 0) 2621 break; 2622 } 2623 ND6_RUNLOCK(); 2624 return (error); 2625 } 2626 SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist, 2627 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, 2628 NULL, 0, nd6_sysctl_drlist, "S,in6_defrouter", 2629 "NDP default router list"); 2630