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/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 82 TAILQ_HEAD(nd6_drhead, nd_defrouter); 83 VNET_DEFINE_STATIC(struct nd6_drhead, nd6_defrouter); 84 #define V_nd6_defrouter VNET(nd6_defrouter) 85 86 VNET_DECLARE(int, nd6_recalc_reachtm_interval); 87 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) 88 89 VNET_DEFINE_STATIC(struct ifnet *, nd6_defifp); 90 VNET_DEFINE(int, nd6_defifindex); 91 #define V_nd6_defifp VNET(nd6_defifp) 92 93 VNET_DEFINE(int, ip6_use_tempaddr) = 0; 94 95 VNET_DEFINE(int, ip6_desync_factor); 96 VNET_DEFINE(u_int32_t, ip6_temp_preferred_lifetime) = DEF_TEMP_PREFERRED_LIFETIME; 97 VNET_DEFINE(u_int32_t, ip6_temp_valid_lifetime) = DEF_TEMP_VALID_LIFETIME; 98 99 VNET_DEFINE(int, ip6_temp_regen_advance) = TEMPADDR_REGEN_ADVANCE; 100 101 #ifdef EXPERIMENTAL 102 VNET_DEFINE(int, nd6_ignore_ipv6_only_ra) = 1; 103 #endif 104 105 SYSCTL_DECL(_net_inet6_icmp6); 106 107 /* RTPREF_MEDIUM has to be 0! */ 108 #define RTPREF_HIGH 1 109 #define RTPREF_MEDIUM 0 110 #define RTPREF_LOW (-1) 111 #define RTPREF_RESERVED (-2) 112 #define RTPREF_INVALID (-3) /* internal */ 113 114 static void 115 defrouter_ref(struct nd_defrouter *dr) 116 { 117 118 refcount_acquire(&dr->refcnt); 119 } 120 121 void 122 defrouter_rele(struct nd_defrouter *dr) 123 { 124 125 if (refcount_release(&dr->refcnt)) 126 free(dr, M_IP6NDP); 127 } 128 129 /* 130 * Remove a router from the global list and optionally stash it in a 131 * caller-supplied queue. 132 */ 133 static void 134 defrouter_unlink(struct nd_defrouter *dr, struct nd6_drhead *drq) 135 { 136 137 ND6_WLOCK_ASSERT(); 138 139 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry); 140 V_nd6_list_genid++; 141 if (drq != NULL) 142 TAILQ_INSERT_TAIL(drq, dr, dr_entry); 143 } 144 145 /* 146 * Receive Router Solicitation Message - just for routers. 147 * Router solicitation/advertisement is mostly managed by userland program 148 * (rtadvd) so here we have no function like nd6_ra_output(). 149 * 150 * Based on RFC 2461 151 */ 152 void 153 nd6_rs_input(struct mbuf *m, int off, int icmp6len) 154 { 155 struct ifnet *ifp; 156 struct ip6_hdr *ip6; 157 struct nd_router_solicit *nd_rs; 158 struct in6_addr saddr6; 159 union nd_opts ndopts; 160 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 161 char *lladdr; 162 int lladdrlen; 163 164 ifp = m->m_pkthdr.rcvif; 165 166 /* 167 * Accept RS only when V_ip6_forwarding=1 and the interface has 168 * no ND6_IFF_ACCEPT_RTADV. 169 */ 170 if (!V_ip6_forwarding || ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) 171 goto freeit; 172 173 /* RFC 6980: Nodes MUST silently ignore fragments */ 174 if(m->m_flags & M_FRAGMENTED) 175 goto freeit; 176 177 /* Sanity checks */ 178 ip6 = mtod(m, struct ip6_hdr *); 179 if (__predict_false(ip6->ip6_hlim != 255)) { 180 ICMP6STAT_INC(icp6s_invlhlim); 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 (__predict_false(ip6->ip6_hlim != 255)) { 380 ICMP6STAT_INC(icp6s_invlhlim); 381 nd6log((LOG_ERR, 382 "%s: invalid hlim (%d) from %s to %s on %s\n", __func__, 383 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 384 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 385 goto bad; 386 } 387 388 saddr6 = ip6->ip6_src; 389 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 390 nd6log((LOG_ERR, 391 "%s: src %s is not link-local\n", __func__, 392 ip6_sprintf(ip6bufs, &saddr6))); 393 goto bad; 394 } 395 396 if (m->m_len < off + icmp6len) { 397 m = m_pullup(m, off + icmp6len); 398 if (m == NULL) { 399 IP6STAT_INC(ip6s_exthdrtoolong); 400 return; 401 } 402 } 403 ip6 = mtod(m, struct ip6_hdr *); 404 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off); 405 406 icmp6len -= sizeof(*nd_ra); 407 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 408 if (nd6_options(&ndopts) < 0) { 409 nd6log((LOG_INFO, 410 "%s: invalid ND option, ignored\n", __func__)); 411 /* nd6_options have incremented stats */ 412 goto freeit; 413 } 414 415 mcast = 0; 416 dr = NULL; 417 { 418 struct nd_defrouter dr0; 419 u_int32_t advreachable = nd_ra->nd_ra_reachable; 420 421 /* remember if this is a multicasted advertisement */ 422 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 423 mcast = 1; 424 425 bzero(&dr0, sizeof(dr0)); 426 dr0.rtaddr = saddr6; 427 dr0.raflags = nd_ra->nd_ra_flags_reserved; 428 /* 429 * Effectively-disable routes from RA messages when 430 * ND6_IFF_NO_RADR enabled on the receiving interface or 431 * (ip6.forwarding == 1 && ip6.rfc6204w3 != 1). 432 */ 433 if (ndi->flags & ND6_IFF_NO_RADR) 434 dr0.rtlifetime = 0; 435 else if (V_ip6_forwarding && !V_ip6_rfc6204w3) 436 dr0.rtlifetime = 0; 437 else 438 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 439 dr0.expire = time_uptime + dr0.rtlifetime; 440 dr0.ifp = ifp; 441 /* unspecified or not? (RFC 2461 6.3.4) */ 442 if (advreachable) { 443 advreachable = ntohl(advreachable); 444 if (advreachable <= MAX_REACHABLE_TIME && 445 ndi->basereachable != advreachable) { 446 ndi->basereachable = advreachable; 447 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 448 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */ 449 } 450 } 451 if (nd_ra->nd_ra_retransmit) 452 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 453 if (nd_ra->nd_ra_curhoplimit) { 454 if (ndi->chlim < nd_ra->nd_ra_curhoplimit) 455 ndi->chlim = nd_ra->nd_ra_curhoplimit; 456 else if (ndi->chlim != nd_ra->nd_ra_curhoplimit) { 457 log(LOG_ERR, "RA with a lower CurHopLimit sent from " 458 "%s on %s (current = %d, received = %d). " 459 "Ignored.\n", ip6_sprintf(ip6bufs, &ip6->ip6_src), 460 if_name(ifp), ndi->chlim, nd_ra->nd_ra_curhoplimit); 461 } 462 } 463 dr = defrtrlist_update(&dr0); 464 #ifdef EXPERIMENTAL 465 defrtr_ipv6_only_ifp(ifp); 466 #endif 467 } 468 469 /* 470 * prefix 471 */ 472 if (ndopts.nd_opts_pi) { 473 struct nd_opt_hdr *pt; 474 struct nd_opt_prefix_info *pi = NULL; 475 struct nd_prefixctl pr; 476 477 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 478 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 479 pt = (struct nd_opt_hdr *)((caddr_t)pt + 480 (pt->nd_opt_len << 3))) { 481 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 482 continue; 483 pi = (struct nd_opt_prefix_info *)pt; 484 485 if (pi->nd_opt_pi_len != 4) { 486 nd6log((LOG_INFO, 487 "%s: invalid option len %d for prefix " 488 "information option, ignored\n", __func__, 489 pi->nd_opt_pi_len)); 490 continue; 491 } 492 493 if (128 < pi->nd_opt_pi_prefix_len) { 494 nd6log((LOG_INFO, 495 "%s: invalid prefix len %d for prefix " 496 "information option, ignored\n", __func__, 497 pi->nd_opt_pi_prefix_len)); 498 continue; 499 } 500 501 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 502 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 503 nd6log((LOG_INFO, 504 "%s: invalid prefix %s, ignored\n", 505 __func__, ip6_sprintf(ip6bufs, 506 &pi->nd_opt_pi_prefix))); 507 continue; 508 } 509 510 bzero(&pr, sizeof(pr)); 511 pr.ndpr_prefix.sin6_family = AF_INET6; 512 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix); 513 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix; 514 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 515 516 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 517 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 518 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 519 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 520 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 521 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 522 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 523 (void)prelist_update(&pr, dr, m, mcast); 524 } 525 } 526 if (dr != NULL) { 527 defrouter_rele(dr); 528 dr = NULL; 529 } 530 531 /* 532 * MTU 533 */ 534 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 535 u_long mtu; 536 u_long maxmtu; 537 538 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 539 540 /* lower bound */ 541 if (mtu < IPV6_MMTU) { 542 nd6log((LOG_INFO, "%s: bogus mtu option mtu=%lu sent " 543 "from %s, ignoring\n", __func__, 544 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src))); 545 goto skip; 546 } 547 548 /* upper bound */ 549 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 550 ? ndi->maxmtu : ifp->if_mtu; 551 if (mtu <= maxmtu) { 552 int change = (ndi->linkmtu != mtu); 553 554 ndi->linkmtu = mtu; 555 if (change) { 556 /* in6_maxmtu may change */ 557 in6_setmaxmtu(); 558 rt_updatemtu(ifp); 559 } 560 } else { 561 nd6log((LOG_INFO, "%s: bogus mtu=%lu sent from %s; " 562 "exceeds maxmtu %lu, ignoring\n", __func__, 563 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu)); 564 } 565 } 566 567 skip: 568 569 /* 570 * Source link layer address 571 */ 572 { 573 char *lladdr = NULL; 574 int lladdrlen = 0; 575 576 if (ndopts.nd_opts_src_lladdr) { 577 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 578 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 579 } 580 581 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 582 nd6log((LOG_INFO, 583 "%s: lladdrlen mismatch for %s (if %d, RA packet %d)\n", 584 __func__, ip6_sprintf(ip6bufs, &saddr6), 585 ifp->if_addrlen, lladdrlen - 2)); 586 goto bad; 587 } 588 589 nd6_cache_lladdr(ifp, &saddr6, lladdr, 590 lladdrlen, ND_ROUTER_ADVERT, 0); 591 592 /* 593 * Installing a link-layer address might change the state of the 594 * router's neighbor cache, which might also affect our on-link 595 * detection of adveritsed prefixes. 596 */ 597 pfxlist_onlink_check(); 598 } 599 600 freeit: 601 m_freem(m); 602 return; 603 604 bad: 605 ICMP6STAT_INC(icp6s_badra); 606 m_freem(m); 607 } 608 609 /* PFXRTR */ 610 static struct nd_pfxrouter * 611 pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 612 { 613 struct nd_pfxrouter *search; 614 615 ND6_LOCK_ASSERT(); 616 617 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) { 618 if (search->router == dr) 619 break; 620 } 621 return (search); 622 } 623 624 static void 625 pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 626 { 627 struct nd_pfxrouter *new; 628 bool update; 629 630 ND6_UNLOCK_ASSERT(); 631 632 ND6_RLOCK(); 633 if (pfxrtr_lookup(pr, dr) != NULL) { 634 ND6_RUNLOCK(); 635 return; 636 } 637 ND6_RUNLOCK(); 638 639 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 640 if (new == NULL) 641 return; 642 defrouter_ref(dr); 643 new->router = dr; 644 645 ND6_WLOCK(); 646 if (pfxrtr_lookup(pr, dr) == NULL) { 647 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 648 update = true; 649 } else { 650 /* We lost a race to add the reference. */ 651 defrouter_rele(dr); 652 free(new, M_IP6NDP); 653 update = false; 654 } 655 ND6_WUNLOCK(); 656 657 if (update) 658 pfxlist_onlink_check(); 659 } 660 661 static void 662 pfxrtr_del(struct nd_pfxrouter *pfr) 663 { 664 665 ND6_WLOCK_ASSERT(); 666 667 LIST_REMOVE(pfr, pfr_entry); 668 defrouter_rele(pfr->router); 669 free(pfr, M_IP6NDP); 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 rt_addrinfo info; 678 struct rib_cmd_info rc; 679 unsigned int fibnum; 680 int error; 681 682 bzero(&def, sizeof(def)); 683 bzero(&mask, sizeof(mask)); 684 bzero(&gate, sizeof(gate)); 685 686 def.sin6_len = mask.sin6_len = gate.sin6_len = 687 sizeof(struct sockaddr_in6); 688 def.sin6_family = gate.sin6_family = AF_INET6; 689 gate.sin6_addr = new->rtaddr; 690 fibnum = new->ifp->if_fib; 691 692 bzero((caddr_t)&info, sizeof(info)); 693 info.rti_flags = RTF_GATEWAY; 694 info.rti_info[RTAX_DST] = (struct sockaddr *)&def; 695 info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&gate; 696 info.rti_info[RTAX_NETMASK] = (struct sockaddr *)&mask; 697 698 NET_EPOCH_ASSERT(); 699 error = rib_action(fibnum, RTM_ADD, &info, &rc); 700 if (error == 0) { 701 struct nhop_object *nh = nhop_select_func(rc.rc_nh_new, 0); 702 rt_routemsg(RTM_ADD, rc.rc_rt, nh, fibnum); 703 new->installed = 1; 704 } 705 } 706 707 /* 708 * Remove the default route for a given router. 709 * This is just a subroutine function for defrouter_select_fib(), and 710 * should not be called from anywhere else. 711 */ 712 static void 713 defrouter_delreq(struct nd_defrouter *dr) 714 { 715 struct sockaddr_in6 def, mask, gate; 716 struct rt_addrinfo info; 717 struct rib_cmd_info rc; 718 struct epoch_tracker et; 719 unsigned int fibnum; 720 int error; 721 722 bzero(&def, sizeof(def)); 723 bzero(&mask, sizeof(mask)); 724 bzero(&gate, sizeof(gate)); 725 726 def.sin6_len = mask.sin6_len = gate.sin6_len = 727 sizeof(struct sockaddr_in6); 728 def.sin6_family = gate.sin6_family = AF_INET6; 729 gate.sin6_addr = dr->rtaddr; 730 fibnum = dr->ifp->if_fib; 731 732 bzero((caddr_t)&info, sizeof(info)); 733 info.rti_flags = RTF_GATEWAY; 734 info.rti_info[RTAX_DST] = (struct sockaddr *)&def; 735 info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&gate; 736 info.rti_info[RTAX_NETMASK] = (struct sockaddr *)&mask; 737 738 NET_EPOCH_ENTER(et); 739 error = rib_action(fibnum, RTM_DELETE, &info, &rc); 740 if (error == 0) { 741 struct nhop_object *nh = nhop_select_func(rc.rc_nh_old, 0); 742 rt_routemsg(RTM_DELETE, rc.rc_rt, nh, fibnum); 743 } 744 NET_EPOCH_EXIT(et); 745 746 dr->installed = 0; 747 } 748 749 static void 750 defrouter_del(struct nd_defrouter *dr) 751 { 752 struct nd_defrouter *deldr = NULL; 753 struct nd_prefix *pr; 754 struct nd_pfxrouter *pfxrtr; 755 756 ND6_UNLOCK_ASSERT(); 757 758 /* 759 * Flush all the routing table entries that use the router 760 * as a next hop. 761 */ 762 if (ND_IFINFO(dr->ifp)->flags & ND6_IFF_ACCEPT_RTADV) 763 rt6_flush(&dr->rtaddr, dr->ifp); 764 765 #ifdef EXPERIMENTAL 766 defrtr_ipv6_only_ifp(dr->ifp); 767 #endif 768 769 if (dr->installed) { 770 deldr = dr; 771 defrouter_delreq(dr); 772 } 773 774 /* 775 * Also delete all the pointers to the router in each prefix lists. 776 */ 777 ND6_WLOCK(); 778 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 779 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 780 pfxrtr_del(pfxrtr); 781 } 782 ND6_WUNLOCK(); 783 784 pfxlist_onlink_check(); 785 786 /* 787 * If the router is the primary one, choose a new one. 788 * Note that defrouter_select_fib() will remove the current 789 * gateway from the routing table. 790 */ 791 if (deldr) 792 defrouter_select_fib(deldr->ifp->if_fib); 793 794 /* 795 * Release the list reference. 796 */ 797 defrouter_rele(dr); 798 } 799 800 struct nd_defrouter * 801 defrouter_lookup_locked(const struct in6_addr *addr, struct ifnet *ifp) 802 { 803 struct nd_defrouter *dr; 804 805 ND6_LOCK_ASSERT(); 806 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 807 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) { 808 defrouter_ref(dr); 809 return (dr); 810 } 811 return (NULL); 812 } 813 814 struct nd_defrouter * 815 defrouter_lookup(const struct in6_addr *addr, struct ifnet *ifp) 816 { 817 struct nd_defrouter *dr; 818 819 ND6_RLOCK(); 820 dr = defrouter_lookup_locked(addr, ifp); 821 ND6_RUNLOCK(); 822 return (dr); 823 } 824 825 /* 826 * Remove all default routes from default router list. 827 */ 828 void 829 defrouter_reset(void) 830 { 831 struct nd_defrouter *dr, **dra; 832 int count, i; 833 834 count = i = 0; 835 836 /* 837 * We can't delete routes with the ND lock held, so make a copy of the 838 * current default router list and use that when deleting routes. 839 */ 840 ND6_RLOCK(); 841 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) 842 count++; 843 ND6_RUNLOCK(); 844 845 dra = malloc(count * sizeof(*dra), M_TEMP, M_WAITOK | M_ZERO); 846 847 ND6_RLOCK(); 848 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 849 if (i == count) 850 break; 851 defrouter_ref(dr); 852 dra[i++] = dr; 853 } 854 ND6_RUNLOCK(); 855 856 for (i = 0; i < count && dra[i] != NULL; i++) { 857 defrouter_delreq(dra[i]); 858 defrouter_rele(dra[i]); 859 } 860 free(dra, M_TEMP); 861 862 /* 863 * XXX should we also nuke any default routers in the kernel, by 864 * going through them by rtalloc1()? 865 */ 866 } 867 868 /* 869 * Look up a matching default router list entry and remove it. Returns true if a 870 * matching entry was found, false otherwise. 871 */ 872 bool 873 defrouter_remove(struct in6_addr *addr, struct ifnet *ifp) 874 { 875 struct nd_defrouter *dr; 876 877 ND6_WLOCK(); 878 dr = defrouter_lookup_locked(addr, ifp); 879 if (dr == NULL) { 880 ND6_WUNLOCK(); 881 return (false); 882 } 883 884 defrouter_unlink(dr, NULL); 885 ND6_WUNLOCK(); 886 defrouter_del(dr); 887 defrouter_rele(dr); 888 return (true); 889 } 890 891 /* 892 * for default router selection 893 * regards router-preference field as a 2-bit signed integer 894 */ 895 static int 896 rtpref(struct nd_defrouter *dr) 897 { 898 switch (dr->raflags & ND_RA_FLAG_RTPREF_MASK) { 899 case ND_RA_FLAG_RTPREF_HIGH: 900 return (RTPREF_HIGH); 901 case ND_RA_FLAG_RTPREF_MEDIUM: 902 case ND_RA_FLAG_RTPREF_RSV: 903 return (RTPREF_MEDIUM); 904 case ND_RA_FLAG_RTPREF_LOW: 905 return (RTPREF_LOW); 906 default: 907 /* 908 * This case should never happen. If it did, it would mean a 909 * serious bug of kernel internal. We thus always bark here. 910 * Or, can we even panic? 911 */ 912 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->raflags); 913 return (RTPREF_INVALID); 914 } 915 /* NOTREACHED */ 916 } 917 918 /* 919 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 920 * draft-ietf-ipngwg-router-selection: 921 * 1) Routers that are reachable or probably reachable should be preferred. 922 * If we have more than one (probably) reachable router, prefer ones 923 * with the highest router preference. 924 * 2) When no routers on the list are known to be reachable or 925 * probably reachable, routers SHOULD be selected in a round-robin 926 * fashion, regardless of router preference values. 927 * 3) If the Default Router List is empty, assume that all 928 * destinations are on-link. 929 * 930 * We assume nd_defrouter is sorted by router preference value. 931 * Since the code below covers both with and without router preference cases, 932 * we do not need to classify the cases by ifdef. 933 * 934 * At this moment, we do not try to install more than one default router, 935 * even when the multipath routing is available, because we're not sure about 936 * the benefits for stub hosts comparing to the risk of making the code 937 * complicated and the possibility of introducing bugs. 938 * 939 * We maintain a single list of routers for multiple FIBs, only considering one 940 * at a time based on the receiving interface's FIB. If @fibnum is RT_ALL_FIBS, 941 * we do the whole thing multiple times. 942 */ 943 void 944 defrouter_select_fib(int fibnum) 945 { 946 struct epoch_tracker et; 947 struct nd_defrouter *dr, *selected_dr, *installed_dr; 948 struct llentry *ln = NULL; 949 950 if (fibnum == RT_ALL_FIBS) { 951 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) { 952 defrouter_select_fib(fibnum); 953 } 954 } 955 956 ND6_RLOCK(); 957 /* 958 * Let's handle easy case (3) first: 959 * If default router list is empty, there's nothing to be done. 960 */ 961 if (TAILQ_EMPTY(&V_nd6_defrouter)) { 962 ND6_RUNLOCK(); 963 return; 964 } 965 966 /* 967 * Search for a (probably) reachable router from the list. 968 * We just pick up the first reachable one (if any), assuming that 969 * the ordering rule of the list described in defrtrlist_update(). 970 */ 971 selected_dr = installed_dr = NULL; 972 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 973 NET_EPOCH_ENTER(et); 974 if (selected_dr == NULL && dr->ifp->if_fib == fibnum && 975 (ln = nd6_lookup(&dr->rtaddr, LLE_SF(AF_INET6, 0), dr->ifp)) && 976 ND6_IS_LLINFO_PROBREACH(ln)) { 977 selected_dr = dr; 978 defrouter_ref(selected_dr); 979 } 980 NET_EPOCH_EXIT(et); 981 if (ln != NULL) { 982 LLE_RUNLOCK(ln); 983 ln = NULL; 984 } 985 986 if (dr->installed && dr->ifp->if_fib == fibnum) { 987 if (installed_dr == NULL) { 988 installed_dr = dr; 989 defrouter_ref(installed_dr); 990 } else { 991 /* 992 * this should not happen. 993 * warn for diagnosis. 994 */ 995 log(LOG_ERR, "defrouter_select_fib: more than " 996 "one router is installed\n"); 997 } 998 } 999 } 1000 /* 1001 * If none of the default routers was found to be reachable, 1002 * round-robin the list regardless of preference. 1003 * Otherwise, if we have an installed router, check if the selected 1004 * (reachable) router should really be preferred to the installed one. 1005 * We only prefer the new router when the old one is not reachable 1006 * or when the new one has a really higher preference value. 1007 */ 1008 if (selected_dr == NULL) { 1009 if (installed_dr == NULL || 1010 TAILQ_NEXT(installed_dr, dr_entry) == NULL) 1011 dr = TAILQ_FIRST(&V_nd6_defrouter); 1012 else 1013 dr = TAILQ_NEXT(installed_dr, dr_entry); 1014 1015 /* Ensure we select a router for this FIB. */ 1016 TAILQ_FOREACH_FROM(dr, &V_nd6_defrouter, dr_entry) { 1017 if (dr->ifp->if_fib == fibnum) { 1018 selected_dr = dr; 1019 defrouter_ref(selected_dr); 1020 break; 1021 } 1022 } 1023 } else if (installed_dr != NULL) { 1024 NET_EPOCH_ENTER(et); 1025 if ((ln = nd6_lookup(&installed_dr->rtaddr, 0, 1026 installed_dr->ifp)) && 1027 ND6_IS_LLINFO_PROBREACH(ln) && 1028 installed_dr->ifp->if_fib == fibnum && 1029 rtpref(selected_dr) <= rtpref(installed_dr)) { 1030 defrouter_rele(selected_dr); 1031 selected_dr = installed_dr; 1032 } 1033 NET_EPOCH_EXIT(et); 1034 if (ln != NULL) 1035 LLE_RUNLOCK(ln); 1036 } 1037 ND6_RUNLOCK(); 1038 1039 NET_EPOCH_ENTER(et); 1040 /* 1041 * If we selected a router for this FIB and it's different 1042 * than the installed one, remove the installed router and 1043 * install the selected one in its place. 1044 */ 1045 if (installed_dr != selected_dr) { 1046 if (installed_dr != NULL) { 1047 defrouter_delreq(installed_dr); 1048 defrouter_rele(installed_dr); 1049 } 1050 if (selected_dr != NULL) 1051 defrouter_addreq(selected_dr); 1052 } 1053 if (selected_dr != NULL) 1054 defrouter_rele(selected_dr); 1055 NET_EPOCH_EXIT(et); 1056 } 1057 1058 static struct nd_defrouter * 1059 defrtrlist_update(struct nd_defrouter *new) 1060 { 1061 struct nd_defrouter *dr, *n; 1062 uint64_t genid; 1063 int oldpref; 1064 bool writelocked; 1065 1066 if (new->rtlifetime == 0) { 1067 defrouter_remove(&new->rtaddr, new->ifp); 1068 return (NULL); 1069 } 1070 1071 ND6_RLOCK(); 1072 writelocked = false; 1073 restart: 1074 dr = defrouter_lookup_locked(&new->rtaddr, new->ifp); 1075 if (dr != NULL) { 1076 oldpref = rtpref(dr); 1077 1078 /* override */ 1079 dr->raflags = new->raflags; /* XXX flag check */ 1080 dr->rtlifetime = new->rtlifetime; 1081 dr->expire = new->expire; 1082 1083 /* 1084 * If the preference does not change, there's no need 1085 * to sort the entries. Also make sure the selected 1086 * router is still installed in the kernel. 1087 */ 1088 if (dr->installed && rtpref(new) == oldpref) { 1089 if (writelocked) 1090 ND6_WUNLOCK(); 1091 else 1092 ND6_RUNLOCK(); 1093 return (dr); 1094 } 1095 } 1096 1097 /* 1098 * The router needs to be reinserted into the default router 1099 * list, so upgrade to a write lock. If that fails and the list 1100 * has potentially changed while the lock was dropped, we'll 1101 * redo the lookup with the write lock held. 1102 */ 1103 if (!writelocked) { 1104 writelocked = true; 1105 if (!ND6_TRY_UPGRADE()) { 1106 genid = V_nd6_list_genid; 1107 ND6_RUNLOCK(); 1108 ND6_WLOCK(); 1109 if (genid != V_nd6_list_genid) 1110 goto restart; 1111 } 1112 } 1113 1114 if (dr != NULL) { 1115 /* 1116 * The preferred router may have changed, so relocate this 1117 * router. 1118 */ 1119 TAILQ_REMOVE(&V_nd6_defrouter, dr, dr_entry); 1120 n = dr; 1121 } else { 1122 n = malloc(sizeof(*n), M_IP6NDP, M_NOWAIT | M_ZERO); 1123 if (n == NULL) { 1124 ND6_WUNLOCK(); 1125 return (NULL); 1126 } 1127 memcpy(n, new, sizeof(*n)); 1128 /* Initialize with an extra reference for the caller. */ 1129 refcount_init(&n->refcnt, 2); 1130 } 1131 1132 /* 1133 * Insert the new router in the Default Router List; 1134 * The Default Router List should be in the descending order 1135 * of router-preferece. Routers with the same preference are 1136 * sorted in the arriving time order. 1137 */ 1138 1139 /* insert at the end of the group */ 1140 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 1141 if (rtpref(n) > rtpref(dr)) 1142 break; 1143 } 1144 if (dr != NULL) 1145 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 1146 else 1147 TAILQ_INSERT_TAIL(&V_nd6_defrouter, n, dr_entry); 1148 V_nd6_list_genid++; 1149 ND6_WUNLOCK(); 1150 1151 defrouter_select_fib(new->ifp->if_fib); 1152 1153 return (n); 1154 } 1155 1156 static int 1157 in6_init_prefix_ltimes(struct nd_prefix *ndpr) 1158 { 1159 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 1160 ndpr->ndpr_preferred = 0; 1161 else 1162 ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime; 1163 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1164 ndpr->ndpr_expire = 0; 1165 else 1166 ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime; 1167 1168 return 0; 1169 } 1170 1171 static void 1172 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6) 1173 { 1174 /* init ia6t_expire */ 1175 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 1176 lt6->ia6t_expire = 0; 1177 else { 1178 lt6->ia6t_expire = time_uptime; 1179 lt6->ia6t_expire += lt6->ia6t_vltime; 1180 } 1181 1182 /* init ia6t_preferred */ 1183 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 1184 lt6->ia6t_preferred = 0; 1185 else { 1186 lt6->ia6t_preferred = time_uptime; 1187 lt6->ia6t_preferred += lt6->ia6t_pltime; 1188 } 1189 } 1190 1191 static struct in6_ifaddr * 1192 in6_ifadd(struct nd_prefixctl *pr, int mcast) 1193 { 1194 struct ifnet *ifp = pr->ndpr_ifp; 1195 struct ifaddr *ifa; 1196 struct in6_aliasreq ifra; 1197 struct in6_ifaddr *ia, *ib; 1198 int error, plen0; 1199 struct in6_addr mask; 1200 int prefixlen = pr->ndpr_plen; 1201 int updateflags; 1202 char ip6buf[INET6_ADDRSTRLEN]; 1203 1204 in6_prefixlen2mask(&mask, prefixlen); 1205 1206 /* 1207 * find a link-local address (will be interface ID). 1208 * Is it really mandatory? Theoretically, a global or a site-local 1209 * address can be configured without a link-local address, if we 1210 * have a unique interface identifier... 1211 * 1212 * it is not mandatory to have a link-local address, we can generate 1213 * interface identifier on the fly. we do this because: 1214 * (1) it should be the easiest way to find interface identifier. 1215 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1216 * for multiple addresses on a single interface, and possible shortcut 1217 * of DAD. we omitted DAD for this reason in the past. 1218 * (3) a user can prevent autoconfiguration of global address 1219 * by removing link-local address by hand (this is partly because we 1220 * don't have other way to control the use of IPv6 on an interface. 1221 * this has been our design choice - cf. NRL's "ifconfig auto"). 1222 * (4) it is easier to manage when an interface has addresses 1223 * with the same interface identifier, than to have multiple addresses 1224 * with different interface identifiers. 1225 */ 1226 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1227 if (ifa) 1228 ib = (struct in6_ifaddr *)ifa; 1229 else 1230 return NULL; 1231 1232 /* prefixlen + ifidlen must be equal to 128 */ 1233 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1234 if (prefixlen != plen0) { 1235 ifa_free(ifa); 1236 nd6log((LOG_INFO, 1237 "%s: wrong prefixlen for %s (prefix=%d ifid=%d)\n", 1238 __func__, if_name(ifp), prefixlen, 128 - plen0)); 1239 return NULL; 1240 } 1241 1242 /* make ifaddr */ 1243 in6_prepare_ifra(&ifra, &pr->ndpr_prefix.sin6_addr, &mask); 1244 1245 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, &mask); 1246 /* interface ID */ 1247 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1248 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1249 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1250 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1251 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1252 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1253 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1254 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1255 ifa_free(ifa); 1256 1257 /* lifetimes. */ 1258 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1259 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1260 1261 /* XXX: scope zone ID? */ 1262 1263 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1264 1265 /* 1266 * Make sure that we do not have this address already. This should 1267 * usually not happen, but we can still see this case, e.g., if we 1268 * have manually configured the exact address to be configured. 1269 */ 1270 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 1271 &ifra.ifra_addr.sin6_addr); 1272 if (ifa != NULL) { 1273 ifa_free(ifa); 1274 /* this should be rare enough to make an explicit log */ 1275 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1276 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr)); 1277 return (NULL); 1278 } 1279 1280 /* 1281 * Allocate ifaddr structure, link into chain, etc. 1282 * If we are going to create a new address upon receiving a multicasted 1283 * RA, we need to impose a random delay before starting DAD. 1284 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1285 */ 1286 updateflags = 0; 1287 if (mcast) 1288 updateflags |= IN6_IFAUPDATE_DADDELAY; 1289 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 1290 nd6log((LOG_ERR, 1291 "%s: failed to make ifaddr %s on %s (errno=%d)\n", __func__, 1292 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr), 1293 if_name(ifp), error)); 1294 return (NULL); /* ifaddr must not have been allocated. */ 1295 } 1296 1297 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1298 /* 1299 * XXXRW: Assumption of non-NULLness here might not be true with 1300 * fine-grained locking -- should we validate it? Or just return 1301 * earlier ifa rather than looking it up again? 1302 */ 1303 return (ia); /* this is always non-NULL and referenced. */ 1304 } 1305 1306 static struct nd_prefix * 1307 nd6_prefix_lookup_locked(struct nd_prefixctl *key) 1308 { 1309 struct nd_prefix *search; 1310 1311 ND6_LOCK_ASSERT(); 1312 1313 LIST_FOREACH(search, &V_nd_prefix, ndpr_entry) { 1314 if (key->ndpr_ifp == search->ndpr_ifp && 1315 key->ndpr_plen == search->ndpr_plen && 1316 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 1317 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 1318 nd6_prefix_ref(search); 1319 break; 1320 } 1321 } 1322 return (search); 1323 } 1324 1325 struct nd_prefix * 1326 nd6_prefix_lookup(struct nd_prefixctl *key) 1327 { 1328 struct nd_prefix *search; 1329 1330 ND6_RLOCK(); 1331 search = nd6_prefix_lookup_locked(key); 1332 ND6_RUNLOCK(); 1333 return (search); 1334 } 1335 1336 void 1337 nd6_prefix_ref(struct nd_prefix *pr) 1338 { 1339 1340 refcount_acquire(&pr->ndpr_refcnt); 1341 } 1342 1343 void 1344 nd6_prefix_rele(struct nd_prefix *pr) 1345 { 1346 1347 if (refcount_release(&pr->ndpr_refcnt)) { 1348 KASSERT(LIST_EMPTY(&pr->ndpr_advrtrs), 1349 ("prefix %p has advertising routers", pr)); 1350 free(pr, M_IP6NDP); 1351 } 1352 } 1353 1354 int 1355 nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 1356 struct nd_prefix **newp) 1357 { 1358 struct nd_prefix *new; 1359 char ip6buf[INET6_ADDRSTRLEN]; 1360 int error; 1361 1362 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 1363 if (new == NULL) 1364 return (ENOMEM); 1365 refcount_init(&new->ndpr_refcnt, newp != NULL ? 2 : 1); 1366 new->ndpr_ifp = pr->ndpr_ifp; 1367 new->ndpr_prefix = pr->ndpr_prefix; 1368 new->ndpr_plen = pr->ndpr_plen; 1369 new->ndpr_vltime = pr->ndpr_vltime; 1370 new->ndpr_pltime = pr->ndpr_pltime; 1371 new->ndpr_flags = pr->ndpr_flags; 1372 if ((error = in6_init_prefix_ltimes(new)) != 0) { 1373 free(new, M_IP6NDP); 1374 return (error); 1375 } 1376 new->ndpr_lastupdate = time_uptime; 1377 1378 /* initialization */ 1379 LIST_INIT(&new->ndpr_advrtrs); 1380 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 1381 /* make prefix in the canonical form */ 1382 IN6_MASK_ADDR(&new->ndpr_prefix.sin6_addr, &new->ndpr_mask); 1383 1384 ND6_WLOCK(); 1385 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry); 1386 V_nd6_list_genid++; 1387 ND6_WUNLOCK(); 1388 1389 /* ND_OPT_PI_FLAG_ONLINK processing */ 1390 if (new->ndpr_raf_onlink) { 1391 struct epoch_tracker et; 1392 1393 ND6_ONLINK_LOCK(); 1394 NET_EPOCH_ENTER(et); 1395 if ((error = nd6_prefix_onlink(new)) != 0) { 1396 nd6log((LOG_ERR, "%s: failed to make the prefix %s/%d " 1397 "on-link on %s (errno=%d)\n", __func__, 1398 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1399 pr->ndpr_plen, if_name(pr->ndpr_ifp), error)); 1400 /* proceed anyway. XXX: is it correct? */ 1401 } 1402 NET_EPOCH_EXIT(et); 1403 ND6_ONLINK_UNLOCK(); 1404 } 1405 1406 if (dr != NULL) 1407 pfxrtr_add(new, dr); 1408 if (newp != NULL) 1409 *newp = new; 1410 return (0); 1411 } 1412 1413 /* 1414 * Remove a prefix from the prefix list and optionally stash it in a 1415 * caller-provided list. 1416 * 1417 * The ND6 lock must be held. 1418 */ 1419 void 1420 nd6_prefix_unlink(struct nd_prefix *pr, struct nd_prhead *list) 1421 { 1422 1423 ND6_WLOCK_ASSERT(); 1424 1425 LIST_REMOVE(pr, ndpr_entry); 1426 V_nd6_list_genid++; 1427 if (list != NULL) 1428 LIST_INSERT_HEAD(list, pr, ndpr_entry); 1429 } 1430 1431 /* 1432 * Free an unlinked prefix, first marking it off-link if necessary. 1433 */ 1434 void 1435 nd6_prefix_del(struct nd_prefix *pr) 1436 { 1437 struct nd_pfxrouter *pfr, *next; 1438 int e; 1439 char ip6buf[INET6_ADDRSTRLEN]; 1440 1441 KASSERT(pr->ndpr_addrcnt == 0, 1442 ("prefix %p has referencing addresses", pr)); 1443 ND6_UNLOCK_ASSERT(); 1444 1445 /* 1446 * Though these flags are now meaningless, we'd rather keep the value 1447 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users 1448 * when executing "ndp -p". 1449 */ 1450 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1451 ND6_ONLINK_LOCK(); 1452 if ((e = nd6_prefix_offlink(pr)) != 0) { 1453 nd6log((LOG_ERR, 1454 "%s: failed to make the prefix %s/%d offlink on %s " 1455 "(errno=%d)\n", __func__, 1456 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1457 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1458 /* what should we do? */ 1459 } 1460 ND6_ONLINK_UNLOCK(); 1461 } 1462 1463 /* Release references to routers that have advertised this prefix. */ 1464 ND6_WLOCK(); 1465 LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next) 1466 pfxrtr_del(pfr); 1467 ND6_WUNLOCK(); 1468 1469 nd6_prefix_rele(pr); 1470 1471 pfxlist_onlink_check(); 1472 } 1473 1474 static int 1475 prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr, 1476 struct mbuf *m, int mcast) 1477 { 1478 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 1479 struct ifaddr *ifa; 1480 struct ifnet *ifp = new->ndpr_ifp; 1481 struct nd_prefix *pr; 1482 int error = 0; 1483 int auth; 1484 struct in6_addrlifetime lt6_tmp; 1485 char ip6buf[INET6_ADDRSTRLEN]; 1486 1487 NET_EPOCH_ASSERT(); 1488 1489 auth = 0; 1490 if (m) { 1491 /* 1492 * Authenticity for NA consists authentication for 1493 * both IP header and IP datagrams, doesn't it ? 1494 */ 1495 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1496 auth = ((m->m_flags & M_AUTHIPHDR) && 1497 (m->m_flags & M_AUTHIPDGM)); 1498 #endif 1499 } 1500 1501 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1502 /* 1503 * nd6_prefix_lookup() ensures that pr and new have the same 1504 * prefix on a same interface. 1505 */ 1506 1507 /* 1508 * Update prefix information. Note that the on-link (L) bit 1509 * and the autonomous (A) bit should NOT be changed from 1 1510 * to 0. 1511 */ 1512 if (new->ndpr_raf_onlink == 1) 1513 pr->ndpr_raf_onlink = 1; 1514 if (new->ndpr_raf_auto == 1) 1515 pr->ndpr_raf_auto = 1; 1516 if (new->ndpr_raf_onlink) { 1517 pr->ndpr_vltime = new->ndpr_vltime; 1518 pr->ndpr_pltime = new->ndpr_pltime; 1519 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1520 pr->ndpr_lastupdate = time_uptime; 1521 } 1522 1523 if (new->ndpr_raf_onlink && 1524 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1525 ND6_ONLINK_LOCK(); 1526 if ((error = nd6_prefix_onlink(pr)) != 0) { 1527 nd6log((LOG_ERR, 1528 "%s: failed to make the prefix %s/%d " 1529 "on-link on %s (errno=%d)\n", __func__, 1530 ip6_sprintf(ip6buf, 1531 &pr->ndpr_prefix.sin6_addr), 1532 pr->ndpr_plen, if_name(pr->ndpr_ifp), 1533 error)); 1534 /* proceed anyway. XXX: is it correct? */ 1535 } 1536 ND6_ONLINK_UNLOCK(); 1537 } 1538 1539 if (dr != NULL) 1540 pfxrtr_add(pr, dr); 1541 } else { 1542 if (new->ndpr_vltime == 0) 1543 goto end; 1544 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1545 goto end; 1546 1547 error = nd6_prelist_add(new, dr, &pr); 1548 if (error != 0) { 1549 nd6log((LOG_NOTICE, "%s: nd6_prelist_add() failed for " 1550 "the prefix %s/%d on %s (errno=%d)\n", __func__, 1551 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr), 1552 new->ndpr_plen, if_name(new->ndpr_ifp), error)); 1553 goto end; /* we should just give up in this case. */ 1554 } 1555 1556 /* 1557 * XXX: from the ND point of view, we can ignore a prefix 1558 * with the on-link bit being zero. However, we need a 1559 * prefix structure for references from autoconfigured 1560 * addresses. Thus, we explicitly make sure that the prefix 1561 * itself expires now. 1562 */ 1563 if (pr->ndpr_raf_onlink == 0) { 1564 pr->ndpr_vltime = 0; 1565 pr->ndpr_pltime = 0; 1566 in6_init_prefix_ltimes(pr); 1567 } 1568 } 1569 1570 /* 1571 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1572 * Note that pr must be non NULL at this point. 1573 */ 1574 1575 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1576 if (!new->ndpr_raf_auto) 1577 goto end; 1578 1579 /* 1580 * 5.5.3 (b). the link-local prefix should have been ignored in 1581 * nd6_ra_input. 1582 */ 1583 1584 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1585 if (new->ndpr_pltime > new->ndpr_vltime) { 1586 error = EINVAL; /* XXX: won't be used */ 1587 goto end; 1588 } 1589 1590 /* 1591 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1592 * an address configured by stateless autoconfiguration already in the 1593 * list of addresses associated with the interface, and the Valid 1594 * Lifetime is not 0, form an address. We first check if we have 1595 * a matching prefix. 1596 * Note: we apply a clarification in rfc2462bis-02 here. We only 1597 * consider autoconfigured addresses while RFC2462 simply said 1598 * "address". 1599 */ 1600 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1601 struct in6_ifaddr *ifa6; 1602 u_int32_t remaininglifetime; 1603 1604 if (ifa->ifa_addr->sa_family != AF_INET6) 1605 continue; 1606 1607 ifa6 = (struct in6_ifaddr *)ifa; 1608 1609 /* 1610 * We only consider autoconfigured addresses as per rfc2462bis. 1611 */ 1612 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1613 continue; 1614 1615 /* 1616 * Spec is not clear here, but I believe we should concentrate 1617 * on unicast (i.e. not anycast) addresses. 1618 * XXX: other ia6_flags? detached or duplicated? 1619 */ 1620 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1621 continue; 1622 1623 /* 1624 * Ignore the address if it is not associated with a prefix 1625 * or is associated with a prefix that is different from this 1626 * one. (pr is never NULL here) 1627 */ 1628 if (ifa6->ia6_ndpr != pr) 1629 continue; 1630 1631 if (ia6_match == NULL) /* remember the first one */ 1632 ia6_match = ifa6; 1633 1634 /* 1635 * An already autoconfigured address matched. Now that we 1636 * are sure there is at least one matched address, we can 1637 * proceed to 5.5.3. (e): update the lifetimes according to the 1638 * "two hours" rule and the privacy extension. 1639 * We apply some clarifications in rfc2462bis: 1640 * - use remaininglifetime instead of storedlifetime as a 1641 * variable name 1642 * - remove the dead code in the "two-hour" rule 1643 */ 1644 #define TWOHOUR (120*60) 1645 lt6_tmp = ifa6->ia6_lifetime; 1646 1647 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1648 remaininglifetime = ND6_INFINITE_LIFETIME; 1649 else if (time_uptime - ifa6->ia6_updatetime > 1650 lt6_tmp.ia6t_vltime) { 1651 /* 1652 * The case of "invalid" address. We should usually 1653 * not see this case. 1654 */ 1655 remaininglifetime = 0; 1656 } else 1657 remaininglifetime = lt6_tmp.ia6t_vltime - 1658 (time_uptime - ifa6->ia6_updatetime); 1659 1660 /* when not updating, keep the current stored lifetime. */ 1661 lt6_tmp.ia6t_vltime = remaininglifetime; 1662 1663 if (TWOHOUR < new->ndpr_vltime || 1664 remaininglifetime < new->ndpr_vltime) { 1665 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1666 } else if (remaininglifetime <= TWOHOUR) { 1667 if (auth) { 1668 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1669 } 1670 } else { 1671 /* 1672 * new->ndpr_vltime <= TWOHOUR && 1673 * TWOHOUR < remaininglifetime 1674 */ 1675 lt6_tmp.ia6t_vltime = TWOHOUR; 1676 } 1677 1678 /* The 2 hour rule is not imposed for preferred lifetime. */ 1679 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1680 1681 in6_init_address_ltimes(pr, <6_tmp); 1682 1683 /* 1684 * We need to treat lifetimes for temporary addresses 1685 * differently, according to 1686 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1687 * we only update the lifetimes when they are in the maximum 1688 * intervals. 1689 */ 1690 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1691 u_int32_t maxvltime, maxpltime; 1692 1693 if (V_ip6_temp_valid_lifetime > 1694 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1695 V_ip6_desync_factor)) { 1696 maxvltime = V_ip6_temp_valid_lifetime - 1697 (time_uptime - ifa6->ia6_createtime) - 1698 V_ip6_desync_factor; 1699 } else 1700 maxvltime = 0; 1701 if (V_ip6_temp_preferred_lifetime > 1702 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1703 V_ip6_desync_factor)) { 1704 maxpltime = V_ip6_temp_preferred_lifetime - 1705 (time_uptime - ifa6->ia6_createtime) - 1706 V_ip6_desync_factor; 1707 } else 1708 maxpltime = 0; 1709 1710 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1711 lt6_tmp.ia6t_vltime > maxvltime) { 1712 lt6_tmp.ia6t_vltime = maxvltime; 1713 } 1714 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1715 lt6_tmp.ia6t_pltime > maxpltime) { 1716 lt6_tmp.ia6t_pltime = maxpltime; 1717 } 1718 } 1719 ifa6->ia6_lifetime = lt6_tmp; 1720 ifa6->ia6_updatetime = time_uptime; 1721 } 1722 if (ia6_match == NULL && new->ndpr_vltime) { 1723 int ifidlen; 1724 1725 /* 1726 * 5.5.3 (d) (continued) 1727 * No address matched and the valid lifetime is non-zero. 1728 * Create a new address. 1729 */ 1730 1731 /* 1732 * Prefix Length check: 1733 * If the sum of the prefix length and interface identifier 1734 * length does not equal 128 bits, the Prefix Information 1735 * option MUST be ignored. The length of the interface 1736 * identifier is defined in a separate link-type specific 1737 * document. 1738 */ 1739 ifidlen = in6_if2idlen(ifp); 1740 if (ifidlen < 0) { 1741 /* this should not happen, so we always log it. */ 1742 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1743 if_name(ifp)); 1744 goto end; 1745 } 1746 if (ifidlen + pr->ndpr_plen != 128) { 1747 nd6log((LOG_INFO, 1748 "%s: invalid prefixlen %d for %s, ignored\n", 1749 __func__, pr->ndpr_plen, if_name(ifp))); 1750 goto end; 1751 } 1752 1753 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1754 /* 1755 * note that we should use pr (not new) for reference. 1756 */ 1757 pr->ndpr_addrcnt++; 1758 ia6->ia6_ndpr = pr; 1759 1760 /* 1761 * RFC 3041 3.3 (2). 1762 * When a new public address is created as described 1763 * in RFC2462, also create a new temporary address. 1764 * 1765 * RFC 3041 3.5. 1766 * When an interface connects to a new link, a new 1767 * randomized interface identifier should be generated 1768 * immediately together with a new set of temporary 1769 * addresses. Thus, we specifiy 1 as the 2nd arg of 1770 * in6_tmpifadd(). 1771 */ 1772 if (V_ip6_use_tempaddr) { 1773 int e; 1774 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1775 nd6log((LOG_NOTICE, "%s: failed to " 1776 "create a temporary address " 1777 "(errno=%d)\n", __func__, e)); 1778 } 1779 } 1780 ifa_free(&ia6->ia_ifa); 1781 1782 /* 1783 * A newly added address might affect the status 1784 * of other addresses, so we check and update it. 1785 * XXX: what if address duplication happens? 1786 */ 1787 pfxlist_onlink_check(); 1788 } else { 1789 /* just set an error. do not bark here. */ 1790 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1791 } 1792 } 1793 1794 end: 1795 if (pr != NULL) 1796 nd6_prefix_rele(pr); 1797 return (error); 1798 } 1799 1800 /* 1801 * A supplement function used in the on-link detection below; 1802 * detect if a given prefix has a (probably) reachable advertising router. 1803 * XXX: lengthy function name... 1804 */ 1805 static struct nd_pfxrouter * 1806 find_pfxlist_reachable_router(struct nd_prefix *pr) 1807 { 1808 struct epoch_tracker et; 1809 struct nd_pfxrouter *pfxrtr; 1810 struct llentry *ln; 1811 int canreach; 1812 1813 ND6_LOCK_ASSERT(); 1814 1815 NET_EPOCH_ENTER(et); 1816 LIST_FOREACH(pfxrtr, &pr->ndpr_advrtrs, pfr_entry) { 1817 ln = nd6_lookup(&pfxrtr->router->rtaddr, LLE_SF(AF_INET6, 0), 1818 pfxrtr->router->ifp); 1819 if (ln == NULL) 1820 continue; 1821 canreach = ND6_IS_LLINFO_PROBREACH(ln); 1822 LLE_RUNLOCK(ln); 1823 if (canreach) 1824 break; 1825 } 1826 NET_EPOCH_EXIT(et); 1827 return (pfxrtr); 1828 } 1829 1830 /* 1831 * Check if each prefix in the prefix list has at least one available router 1832 * that advertised the prefix (a router is "available" if its neighbor cache 1833 * entry is reachable or probably reachable). 1834 * If the check fails, the prefix may be off-link, because, for example, 1835 * we have moved from the network but the lifetime of the prefix has not 1836 * expired yet. So we should not use the prefix if there is another prefix 1837 * that has an available router. 1838 * But, if there is no prefix that has an available router, we still regard 1839 * all the prefixes as on-link. This is because we can't tell if all the 1840 * routers are simply dead or if we really moved from the network and there 1841 * is no router around us. 1842 */ 1843 void 1844 pfxlist_onlink_check(void) 1845 { 1846 struct nd_prefix *pr; 1847 struct in6_ifaddr *ifa; 1848 struct nd_defrouter *dr; 1849 struct nd_pfxrouter *pfxrtr = NULL; 1850 struct rm_priotracker in6_ifa_tracker; 1851 uint64_t genid; 1852 uint32_t flags; 1853 1854 ND6_ONLINK_LOCK(); 1855 ND6_RLOCK(); 1856 1857 /* 1858 * Check if there is a prefix that has a reachable advertising 1859 * router. 1860 */ 1861 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1862 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1863 break; 1864 } 1865 1866 /* 1867 * If we have no such prefix, check whether we still have a router 1868 * that does not advertise any prefixes. 1869 */ 1870 if (pr == NULL) { 1871 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 1872 struct nd_prefix *pr0; 1873 1874 LIST_FOREACH(pr0, &V_nd_prefix, ndpr_entry) { 1875 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1876 break; 1877 } 1878 if (pfxrtr != NULL) 1879 break; 1880 } 1881 } 1882 if (pr != NULL || (!TAILQ_EMPTY(&V_nd6_defrouter) && pfxrtr == NULL)) { 1883 /* 1884 * There is at least one prefix that has a reachable router, 1885 * or at least a router which probably does not advertise 1886 * any prefixes. The latter would be the case when we move 1887 * to a new link where we have a router that does not provide 1888 * prefixes and we configure an address by hand. 1889 * Detach prefixes which have no reachable advertising 1890 * router, and attach other prefixes. 1891 */ 1892 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1893 /* XXX: a link-local prefix should never be detached */ 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 1899 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1900 find_pfxlist_reachable_router(pr) == NULL) 1901 pr->ndpr_stateflags |= NDPRF_DETACHED; 1902 else if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1903 find_pfxlist_reachable_router(pr) != NULL) 1904 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1905 } 1906 } else { 1907 /* there is no prefix that has a reachable router */ 1908 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1909 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1910 pr->ndpr_raf_onlink == 0 || 1911 pr->ndpr_raf_auto == 0) 1912 continue; 1913 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1914 } 1915 } 1916 1917 /* 1918 * Remove each interface route associated with a (just) detached 1919 * prefix, and reinstall the interface route for a (just) attached 1920 * prefix. Note that all attempt of reinstallation does not 1921 * necessarily success, when a same prefix is shared among multiple 1922 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1923 * so we don't have to care about them. 1924 */ 1925 restart: 1926 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1927 char ip6buf[INET6_ADDRSTRLEN]; 1928 int e; 1929 1930 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 1931 pr->ndpr_raf_onlink == 0 || 1932 pr->ndpr_raf_auto == 0) 1933 continue; 1934 1935 flags = pr->ndpr_stateflags & (NDPRF_DETACHED | NDPRF_ONLINK); 1936 if (flags == 0 || flags == (NDPRF_DETACHED | NDPRF_ONLINK)) { 1937 genid = V_nd6_list_genid; 1938 ND6_RUNLOCK(); 1939 if ((flags & NDPRF_ONLINK) != 0 && 1940 (e = nd6_prefix_offlink(pr)) != 0) { 1941 nd6log((LOG_ERR, 1942 "%s: failed to make %s/%d offlink " 1943 "(errno=%d)\n", __func__, 1944 ip6_sprintf(ip6buf, 1945 &pr->ndpr_prefix.sin6_addr), 1946 pr->ndpr_plen, e)); 1947 } else if ((flags & NDPRF_ONLINK) == 0 && 1948 (e = nd6_prefix_onlink(pr)) != 0) { 1949 nd6log((LOG_ERR, 1950 "%s: failed to make %s/%d onlink " 1951 "(errno=%d)\n", __func__, 1952 ip6_sprintf(ip6buf, 1953 &pr->ndpr_prefix.sin6_addr), 1954 pr->ndpr_plen, e)); 1955 } 1956 ND6_RLOCK(); 1957 if (genid != V_nd6_list_genid) 1958 goto restart; 1959 } 1960 } 1961 1962 /* 1963 * Changes on the prefix status might affect address status as well. 1964 * Make sure that all addresses derived from an attached prefix are 1965 * attached, and that all addresses derived from a detached prefix are 1966 * detached. Note, however, that a manually configured address should 1967 * always be attached. 1968 * The precise detection logic is same as the one for prefixes. 1969 */ 1970 IN6_IFADDR_RLOCK(&in6_ifa_tracker); 1971 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1972 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1973 continue; 1974 1975 if (ifa->ia6_ndpr == NULL) { 1976 /* 1977 * This can happen when we first configure the address 1978 * (i.e. the address exists, but the prefix does not). 1979 * XXX: complicated relationships... 1980 */ 1981 continue; 1982 } 1983 1984 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1985 break; 1986 } 1987 if (ifa) { 1988 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1989 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1990 continue; 1991 1992 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1993 continue; 1994 1995 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 1996 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1997 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1998 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1999 nd6_dad_start((struct ifaddr *)ifa, 0); 2000 } 2001 } else { 2002 ifa->ia6_flags |= IN6_IFF_DETACHED; 2003 } 2004 } 2005 } else { 2006 CK_STAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 2007 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 2008 continue; 2009 2010 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 2011 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 2012 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 2013 /* Do we need a delay in this case? */ 2014 nd6_dad_start((struct ifaddr *)ifa, 0); 2015 } 2016 } 2017 } 2018 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker); 2019 ND6_RUNLOCK(); 2020 ND6_ONLINK_UNLOCK(); 2021 } 2022 2023 /* 2024 * Add or remove interface route specified by @dst, @netmask and @ifp. 2025 * ifa can be NULL. 2026 * Returns 0 on success 2027 */ 2028 static int 2029 nd6_prefix_rtrequest(uint32_t fibnum, int cmd, struct sockaddr_in6 *dst, 2030 struct sockaddr_in6 *netmask, struct ifnet *ifp, struct ifaddr *ifa) 2031 { 2032 struct epoch_tracker et; 2033 int error; 2034 2035 /* Prepare gateway */ 2036 struct sockaddr_dl_short sdl = { 2037 .sdl_family = AF_LINK, 2038 .sdl_len = sizeof(struct sockaddr_dl_short), 2039 .sdl_type = ifp->if_type, 2040 .sdl_index = ifp->if_index, 2041 }; 2042 2043 struct rt_addrinfo info = { 2044 .rti_ifa = ifa, 2045 .rti_flags = RTF_PINNED | ((netmask != NULL) ? 0 : RTF_HOST), 2046 .rti_info = { 2047 [RTAX_DST] = (struct sockaddr *)dst, 2048 [RTAX_NETMASK] = (struct sockaddr *)netmask, 2049 [RTAX_GATEWAY] = (struct sockaddr *)&sdl, 2050 }, 2051 }; 2052 /* Don't set additional per-gw filters on removal */ 2053 2054 NET_EPOCH_ENTER(et); 2055 error = rib_handle_ifaddr_info(fibnum, cmd, &info); 2056 NET_EPOCH_EXIT(et); 2057 return (error); 2058 } 2059 2060 static int 2061 nd6_prefix_onlink_rtrequest(struct nd_prefix *pr, struct ifaddr *ifa) 2062 { 2063 int error; 2064 2065 struct sockaddr_in6 mask6 = { 2066 .sin6_family = AF_INET6, 2067 .sin6_len = sizeof(struct sockaddr_in6), 2068 .sin6_addr = pr->ndpr_mask, 2069 }; 2070 struct sockaddr_in6 *pmask6 = (pr->ndpr_plen != 128) ? &mask6 : NULL; 2071 2072 error = nd6_prefix_rtrequest(pr->ndpr_ifp->if_fib, RTM_ADD, 2073 &pr->ndpr_prefix, pmask6, pr->ndpr_ifp, ifa); 2074 if (error == 0) 2075 pr->ndpr_stateflags |= NDPRF_ONLINK; 2076 2077 return (error); 2078 } 2079 2080 static int 2081 nd6_prefix_onlink(struct nd_prefix *pr) 2082 { 2083 struct epoch_tracker et; 2084 struct ifaddr *ifa; 2085 struct ifnet *ifp = pr->ndpr_ifp; 2086 struct nd_prefix *opr; 2087 char ip6buf[INET6_ADDRSTRLEN]; 2088 int error; 2089 2090 ND6_ONLINK_LOCK_ASSERT(); 2091 ND6_UNLOCK_ASSERT(); 2092 2093 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) 2094 return (EEXIST); 2095 2096 /* 2097 * Add the interface route associated with the prefix. Before 2098 * installing the route, check if there's the same prefix on another 2099 * interface, and the prefix has already installed the interface route. 2100 * Although such a configuration is expected to be rare, we explicitly 2101 * allow it. 2102 */ 2103 ND6_RLOCK(); 2104 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 2105 if (opr == pr) 2106 continue; 2107 2108 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 2109 continue; 2110 2111 if (!V_rt_add_addr_allfibs && 2112 opr->ndpr_ifp->if_fib != pr->ndpr_ifp->if_fib) 2113 continue; 2114 2115 if (opr->ndpr_plen == pr->ndpr_plen && 2116 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 2117 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 2118 ND6_RUNLOCK(); 2119 return (0); 2120 } 2121 } 2122 ND6_RUNLOCK(); 2123 2124 /* 2125 * We prefer link-local addresses as the associated interface address. 2126 */ 2127 /* search for a link-local addr */ 2128 NET_EPOCH_ENTER(et); 2129 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 2130 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 2131 if (ifa == NULL) { 2132 /* XXX: freebsd does not have ifa_ifwithaf */ 2133 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 2134 if (ifa->ifa_addr->sa_family == AF_INET6) { 2135 ifa_ref(ifa); 2136 break; 2137 } 2138 } 2139 /* should we care about ia6_flags? */ 2140 } 2141 if (ifa == NULL) { 2142 /* 2143 * This can still happen, when, for example, we receive an RA 2144 * containing a prefix with the L bit set and the A bit clear, 2145 * after removing all IPv6 addresses on the receiving 2146 * interface. This should, of course, be rare though. 2147 */ 2148 nd6log((LOG_NOTICE, 2149 "%s: failed to find any ifaddr to add route for a " 2150 "prefix(%s/%d) on %s\n", __func__, 2151 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 2152 pr->ndpr_plen, if_name(ifp))); 2153 error = 0; 2154 } else { 2155 error = nd6_prefix_onlink_rtrequest(pr, ifa); 2156 ifa_free(ifa); 2157 } 2158 NET_EPOCH_EXIT(et); 2159 2160 return (error); 2161 } 2162 2163 int 2164 nd6_prefix_offlink(struct nd_prefix *pr) 2165 { 2166 int error = 0; 2167 struct ifnet *ifp = pr->ndpr_ifp; 2168 struct nd_prefix *opr; 2169 char ip6buf[INET6_ADDRSTRLEN]; 2170 uint64_t genid; 2171 int a_failure; 2172 2173 ND6_ONLINK_LOCK_ASSERT(); 2174 ND6_UNLOCK_ASSERT(); 2175 2176 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) 2177 return (EEXIST); 2178 2179 struct sockaddr_in6 mask6 = { 2180 .sin6_family = AF_INET6, 2181 .sin6_len = sizeof(struct sockaddr_in6), 2182 .sin6_addr = pr->ndpr_mask, 2183 }; 2184 struct sockaddr_in6 *pmask6 = (pr->ndpr_plen != 128) ? &mask6 : NULL; 2185 2186 error = nd6_prefix_rtrequest(ifp->if_fib, RTM_DELETE, 2187 &pr->ndpr_prefix, pmask6, ifp, NULL); 2188 2189 a_failure = 1; 2190 if (error == 0) { 2191 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 2192 2193 /* 2194 * There might be the same prefix on another interface, 2195 * the prefix which could not be on-link just because we have 2196 * the interface route (see comments in nd6_prefix_onlink). 2197 * If there's one, try to make the prefix on-link on the 2198 * interface. 2199 */ 2200 ND6_RLOCK(); 2201 restart: 2202 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 2203 /* 2204 * KAME specific: detached prefixes should not be 2205 * on-link. 2206 */ 2207 if (opr == pr || (opr->ndpr_stateflags & 2208 (NDPRF_ONLINK | NDPRF_DETACHED)) != 0) 2209 continue; 2210 2211 if (opr->ndpr_plen == pr->ndpr_plen && 2212 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 2213 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 2214 int e; 2215 2216 genid = V_nd6_list_genid; 2217 ND6_RUNLOCK(); 2218 if ((e = nd6_prefix_onlink(opr)) != 0) { 2219 nd6log((LOG_ERR, 2220 "%s: failed to recover a prefix " 2221 "%s/%d from %s to %s (errno=%d)\n", 2222 __func__, ip6_sprintf(ip6buf, 2223 &opr->ndpr_prefix.sin6_addr), 2224 opr->ndpr_plen, if_name(ifp), 2225 if_name(opr->ndpr_ifp), e)); 2226 } else 2227 a_failure = 0; 2228 ND6_RLOCK(); 2229 if (genid != V_nd6_list_genid) 2230 goto restart; 2231 } 2232 } 2233 ND6_RUNLOCK(); 2234 } else { 2235 /* XXX: can we still set the NDPRF_ONLINK flag? */ 2236 nd6log((LOG_ERR, 2237 "%s: failed to delete route: %s/%d on %s (errno=%d)\n", 2238 __func__, ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 2239 pr->ndpr_plen, if_name(ifp), error)); 2240 } 2241 2242 if (a_failure) 2243 lltable_prefix_free(AF_INET6, 2244 (struct sockaddr *)&pr->ndpr_prefix, 2245 (struct sockaddr *)&mask6, LLE_STATIC); 2246 2247 return (error); 2248 } 2249 2250 /* 2251 * ia0 - corresponding public address 2252 */ 2253 int 2254 in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay) 2255 { 2256 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 2257 struct in6_ifaddr *newia; 2258 struct in6_aliasreq ifra; 2259 int error; 2260 int trylimit = 3; /* XXX: adhoc value */ 2261 int updateflags; 2262 u_int32_t randid[2]; 2263 time_t vltime0, pltime0; 2264 2265 in6_prepare_ifra(&ifra, &ia0->ia_addr.sin6_addr, 2266 &ia0->ia_prefixmask.sin6_addr); 2267 2268 ifra.ifra_addr = ia0->ia_addr; /* XXX: do we need this ? */ 2269 /* clear the old IFID */ 2270 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, 2271 &ifra.ifra_prefixmask.sin6_addr); 2272 2273 again: 2274 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 2275 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 2276 nd6log((LOG_NOTICE, "%s: failed to find a good random IFID\n", 2277 __func__)); 2278 return (EINVAL); 2279 } 2280 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 2281 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 2282 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 2283 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 2284 2285 /* 2286 * in6_get_tmpifid() quite likely provided a unique interface ID. 2287 * However, we may still have a chance to see collision, because 2288 * there may be a time lag between generation of the ID and generation 2289 * of the address. So, we'll do one more sanity check. 2290 */ 2291 2292 if (in6_localip(&ifra.ifra_addr.sin6_addr) != 0) { 2293 if (trylimit-- > 0) { 2294 forcegen = 1; 2295 goto again; 2296 } 2297 2298 /* Give up. Something strange should have happened. */ 2299 nd6log((LOG_NOTICE, "%s: failed to find a unique random IFID\n", 2300 __func__)); 2301 return (EEXIST); 2302 } 2303 2304 /* 2305 * The Valid Lifetime is the lower of the Valid Lifetime of the 2306 * public address or TEMP_VALID_LIFETIME. 2307 * The Preferred Lifetime is the lower of the Preferred Lifetime 2308 * of the public address or TEMP_PREFERRED_LIFETIME - 2309 * DESYNC_FACTOR. 2310 */ 2311 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 2312 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 2313 (ia0->ia6_lifetime.ia6t_vltime - 2314 (time_uptime - ia0->ia6_updatetime)); 2315 if (vltime0 > V_ip6_temp_valid_lifetime) 2316 vltime0 = V_ip6_temp_valid_lifetime; 2317 } else 2318 vltime0 = V_ip6_temp_valid_lifetime; 2319 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 2320 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 2321 (ia0->ia6_lifetime.ia6t_pltime - 2322 (time_uptime - ia0->ia6_updatetime)); 2323 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){ 2324 pltime0 = V_ip6_temp_preferred_lifetime - 2325 V_ip6_desync_factor; 2326 } 2327 } else 2328 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor; 2329 ifra.ifra_lifetime.ia6t_vltime = vltime0; 2330 ifra.ifra_lifetime.ia6t_pltime = pltime0; 2331 2332 /* 2333 * A temporary address is created only if this calculated Preferred 2334 * Lifetime is greater than REGEN_ADVANCE time units. 2335 */ 2336 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance) 2337 return (0); 2338 2339 /* XXX: scope zone ID? */ 2340 2341 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2342 2343 /* allocate ifaddr structure, link into chain, etc. */ 2344 updateflags = 0; 2345 if (delay) 2346 updateflags |= IN6_IFAUPDATE_DADDELAY; 2347 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 2348 return (error); 2349 2350 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2351 if (newia == NULL) { /* XXX: can it happen? */ 2352 nd6log((LOG_ERR, 2353 "%s: ifa update succeeded, but we got no ifaddr\n", 2354 __func__)); 2355 return (EINVAL); /* XXX */ 2356 } 2357 newia->ia6_ndpr = ia0->ia6_ndpr; 2358 newia->ia6_ndpr->ndpr_addrcnt++; 2359 ifa_free(&newia->ia_ifa); 2360 2361 /* 2362 * A newly added address might affect the status of other addresses. 2363 * XXX: when the temporary address is generated with a new public 2364 * address, the onlink check is redundant. However, it would be safe 2365 * to do the check explicitly everywhere a new address is generated, 2366 * and, in fact, we surely need the check when we create a new 2367 * temporary address due to deprecation of an old temporary address. 2368 */ 2369 pfxlist_onlink_check(); 2370 2371 return (0); 2372 } 2373 2374 static int 2375 rt6_deleteroute(const struct rtentry *rt, const struct nhop_object *nh, 2376 void *arg) 2377 { 2378 struct in6_addr *gate = (struct in6_addr *)arg; 2379 int nh_rt_flags; 2380 2381 if (nh->gw_sa.sa_family != AF_INET6) 2382 return (0); 2383 2384 if (!IN6_ARE_ADDR_EQUAL(gate, &nh->gw6_sa.sin6_addr)) { 2385 return (0); 2386 } 2387 2388 /* 2389 * Do not delete a static route. 2390 * XXX: this seems to be a bit ad-hoc. Should we consider the 2391 * 'cloned' bit instead? 2392 */ 2393 nh_rt_flags = nhop_get_rtflags(nh); 2394 if ((nh_rt_flags & RTF_STATIC) != 0) 2395 return (0); 2396 2397 /* 2398 * We delete only host route. This means, in particular, we don't 2399 * delete default route. 2400 */ 2401 if ((nh_rt_flags & RTF_HOST) == 0) 2402 return (0); 2403 2404 return (1); 2405 #undef SIN6 2406 } 2407 2408 /* 2409 * Delete all the routing table entries that use the specified gateway. 2410 * XXX: this function causes search through all entries of routing table, so 2411 * it shouldn't be called when acting as a router. 2412 */ 2413 void 2414 rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2415 { 2416 2417 /* We'll care only link-local addresses */ 2418 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) 2419 return; 2420 2421 /* XXX Do we really need to walk any but the default FIB? */ 2422 rib_foreach_table_walk_del(AF_INET6, rt6_deleteroute, (void *)gateway); 2423 } 2424 2425 int 2426 nd6_setdefaultiface(int ifindex) 2427 { 2428 2429 if (V_nd6_defifindex != ifindex) { 2430 V_nd6_defifindex = ifindex; 2431 if (V_nd6_defifindex != 0) { 2432 struct epoch_tracker et; 2433 2434 /* 2435 * XXXGL: this function should use ifnet_byindex_ref! 2436 */ 2437 NET_EPOCH_ENTER(et); 2438 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex); 2439 NET_EPOCH_EXIT(et); 2440 if (V_nd6_defifp == NULL) 2441 return (EINVAL); 2442 } else 2443 V_nd6_defifp = NULL; 2444 2445 /* 2446 * Our current implementation assumes one-to-one mapping between 2447 * interfaces and links, so it would be natural to use the 2448 * default interface as the default link. 2449 */ 2450 scope6_setdefault(V_nd6_defifp); 2451 } 2452 2453 return (0); 2454 } 2455 2456 bool 2457 nd6_defrouter_list_empty(void) 2458 { 2459 2460 return (TAILQ_EMPTY(&V_nd6_defrouter)); 2461 } 2462 2463 void 2464 nd6_defrouter_timer(void) 2465 { 2466 struct nd_defrouter *dr, *ndr; 2467 struct nd6_drhead drq; 2468 2469 TAILQ_INIT(&drq); 2470 2471 ND6_WLOCK(); 2472 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) 2473 if (dr->expire && dr->expire < time_uptime) 2474 defrouter_unlink(dr, &drq); 2475 ND6_WUNLOCK(); 2476 2477 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2478 TAILQ_REMOVE(&drq, dr, dr_entry); 2479 defrouter_del(dr); 2480 } 2481 } 2482 2483 /* 2484 * Nuke default router list entries toward ifp. 2485 * We defer removal of default router list entries that is installed in the 2486 * routing table, in order to keep additional side effects as small as possible. 2487 */ 2488 void 2489 nd6_defrouter_purge(struct ifnet *ifp) 2490 { 2491 struct nd_defrouter *dr, *ndr; 2492 struct nd6_drhead drq; 2493 2494 TAILQ_INIT(&drq); 2495 2496 ND6_WLOCK(); 2497 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) { 2498 if (dr->installed) 2499 continue; 2500 if (dr->ifp == ifp) 2501 defrouter_unlink(dr, &drq); 2502 } 2503 TAILQ_FOREACH_SAFE(dr, &V_nd6_defrouter, dr_entry, ndr) { 2504 if (!dr->installed) 2505 continue; 2506 if (dr->ifp == ifp) 2507 defrouter_unlink(dr, &drq); 2508 } 2509 ND6_WUNLOCK(); 2510 2511 /* Delete the unlinked router objects. */ 2512 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2513 TAILQ_REMOVE(&drq, dr, dr_entry); 2514 defrouter_del(dr); 2515 } 2516 } 2517 2518 void 2519 nd6_defrouter_flush_all(void) 2520 { 2521 struct nd_defrouter *dr; 2522 struct nd6_drhead drq; 2523 2524 TAILQ_INIT(&drq); 2525 2526 ND6_WLOCK(); 2527 while ((dr = TAILQ_FIRST(&V_nd6_defrouter)) != NULL) 2528 defrouter_unlink(dr, &drq); 2529 ND6_WUNLOCK(); 2530 2531 while ((dr = TAILQ_FIRST(&drq)) != NULL) { 2532 TAILQ_REMOVE(&drq, dr, dr_entry); 2533 defrouter_del(dr); 2534 } 2535 } 2536 2537 void 2538 nd6_defrouter_init(void) 2539 { 2540 2541 TAILQ_INIT(&V_nd6_defrouter); 2542 } 2543 2544 static int 2545 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS) 2546 { 2547 struct in6_defrouter d; 2548 struct nd_defrouter *dr; 2549 int error; 2550 2551 if (req->newptr != NULL) 2552 return (EPERM); 2553 2554 error = sysctl_wire_old_buffer(req, 0); 2555 if (error != 0) 2556 return (error); 2557 2558 bzero(&d, sizeof(d)); 2559 d.rtaddr.sin6_family = AF_INET6; 2560 d.rtaddr.sin6_len = sizeof(d.rtaddr); 2561 2562 ND6_RLOCK(); 2563 TAILQ_FOREACH(dr, &V_nd6_defrouter, dr_entry) { 2564 d.rtaddr.sin6_addr = dr->rtaddr; 2565 error = sa6_recoverscope(&d.rtaddr); 2566 if (error != 0) 2567 break; 2568 d.flags = dr->raflags; 2569 d.rtlifetime = dr->rtlifetime; 2570 d.expire = dr->expire + (time_second - time_uptime); 2571 d.if_index = dr->ifp->if_index; 2572 error = SYSCTL_OUT(req, &d, sizeof(d)); 2573 if (error != 0) 2574 break; 2575 } 2576 ND6_RUNLOCK(); 2577 return (error); 2578 } 2579 SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist, 2580 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, 2581 NULL, 0, nd6_sysctl_drlist, "S,in6_defrouter", 2582 "NDP default router list"); 2583