1 /* $FreeBSD$ */ 2 /* $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $ */ 3 4 /*- 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_mac.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/callout.h> 40 #include <sys/mac.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/socket.h> 44 #include <sys/sockio.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/protosw.h> 48 #include <sys/errno.h> 49 #include <sys/syslog.h> 50 #include <sys/queue.h> 51 #include <sys/sysctl.h> 52 53 #include <net/if.h> 54 #include <net/if_arc.h> 55 #include <net/if_dl.h> 56 #include <net/if_types.h> 57 #include <net/iso88025.h> 58 #include <net/fddi.h> 59 #include <net/route.h> 60 61 #include <netinet/in.h> 62 #include <netinet/if_ether.h> 63 #include <netinet6/in6_var.h> 64 #include <netinet/ip6.h> 65 #include <netinet6/ip6_var.h> 66 #include <netinet6/scope6_var.h> 67 #include <netinet6/nd6.h> 68 #include <netinet/icmp6.h> 69 70 #include <sys/limits.h> 71 72 #include <net/net_osdep.h> 73 74 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ 75 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ 76 77 #define SIN6(s) ((struct sockaddr_in6 *)s) 78 #define SDL(s) ((struct sockaddr_dl *)s) 79 80 /* timer values */ 81 int nd6_prune = 1; /* walk list every 1 seconds */ 82 int nd6_delay = 5; /* delay first probe time 5 second */ 83 int nd6_umaxtries = 3; /* maximum unicast query */ 84 int nd6_mmaxtries = 3; /* maximum multicast query */ 85 int nd6_useloopback = 1; /* use loopback interface for local traffic */ 86 int nd6_gctimer = (60 * 60 * 24); /* 1 day: garbage collection timer */ 87 88 /* preventing too many loops in ND option parsing */ 89 int nd6_maxndopt = 10; /* max # of ND options allowed */ 90 91 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */ 92 int nd6_maxqueuelen = 1; /* max # of packets cached in unresolved ND entries */ 93 94 #ifdef ND6_DEBUG 95 int nd6_debug = 1; 96 #else 97 int nd6_debug = 0; 98 #endif 99 100 /* for debugging? */ 101 static int nd6_inuse, nd6_allocated; 102 103 struct llinfo_nd6 llinfo_nd6 = {&llinfo_nd6, &llinfo_nd6}; 104 struct nd_drhead nd_defrouter; 105 struct nd_prhead nd_prefix = { 0 }; 106 107 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL; 108 static struct sockaddr_in6 all1_sa; 109 110 static int nd6_is_new_addr_neighbor __P((struct sockaddr_in6 *, 111 struct ifnet *)); 112 static void nd6_setmtu0 __P((struct ifnet *, struct nd_ifinfo *)); 113 static void nd6_slowtimo __P((void *)); 114 static int regen_tmpaddr __P((struct in6_ifaddr *)); 115 static struct llinfo_nd6 *nd6_free __P((struct rtentry *, int)); 116 static void nd6_llinfo_timer __P((void *)); 117 static void clear_llinfo_pqueue __P((struct llinfo_nd6 *)); 118 119 struct callout nd6_slowtimo_ch; 120 struct callout nd6_timer_ch; 121 extern struct callout in6_tmpaddrtimer_ch; 122 123 void 124 nd6_init() 125 { 126 static int nd6_init_done = 0; 127 int i; 128 129 if (nd6_init_done) { 130 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n"); 131 return; 132 } 133 134 all1_sa.sin6_family = AF_INET6; 135 all1_sa.sin6_len = sizeof(struct sockaddr_in6); 136 for (i = 0; i < sizeof(all1_sa.sin6_addr); i++) 137 all1_sa.sin6_addr.s6_addr[i] = 0xff; 138 139 /* initialization of the default router list */ 140 TAILQ_INIT(&nd_defrouter); 141 142 nd6_init_done = 1; 143 144 /* start timer */ 145 callout_init(&nd6_slowtimo_ch, 0); 146 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 147 nd6_slowtimo, NULL); 148 } 149 150 struct nd_ifinfo * 151 nd6_ifattach(ifp) 152 struct ifnet *ifp; 153 { 154 struct nd_ifinfo *nd; 155 156 nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK); 157 bzero(nd, sizeof(*nd)); 158 159 nd->initialized = 1; 160 161 nd->chlim = IPV6_DEFHLIM; 162 nd->basereachable = REACHABLE_TIME; 163 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 164 nd->retrans = RETRANS_TIMER; 165 /* 166 * Note that the default value of ip6_accept_rtadv is 0, which means 167 * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV 168 * here. 169 */ 170 nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV); 171 172 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 173 nd6_setmtu0(ifp, nd); 174 175 return nd; 176 } 177 178 void 179 nd6_ifdetach(nd) 180 struct nd_ifinfo *nd; 181 { 182 183 free(nd, M_IP6NDP); 184 } 185 186 /* 187 * Reset ND level link MTU. This function is called when the physical MTU 188 * changes, which means we might have to adjust the ND level MTU. 189 */ 190 void 191 nd6_setmtu(ifp) 192 struct ifnet *ifp; 193 { 194 195 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 196 } 197 198 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */ 199 void 200 nd6_setmtu0(ifp, ndi) 201 struct ifnet *ifp; 202 struct nd_ifinfo *ndi; 203 { 204 u_int32_t omaxmtu; 205 206 omaxmtu = ndi->maxmtu; 207 208 switch (ifp->if_type) { 209 case IFT_ARCNET: 210 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */ 211 break; 212 case IFT_FDDI: 213 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); /* RFC2467 */ 214 break; 215 case IFT_ISO88025: 216 ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu); 217 break; 218 default: 219 ndi->maxmtu = ifp->if_mtu; 220 break; 221 } 222 223 /* 224 * Decreasing the interface MTU under IPV6 minimum MTU may cause 225 * undesirable situation. We thus notify the operator of the change 226 * explicitly. The check for omaxmtu is necessary to restrict the 227 * log to the case of changing the MTU, not initializing it. 228 */ 229 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 230 log(LOG_NOTICE, "nd6_setmtu0: " 231 "new link MTU on %s (%lu) is too small for IPv6\n", 232 if_name(ifp), (unsigned long)ndi->maxmtu); 233 } 234 235 if (ndi->maxmtu > in6_maxmtu) 236 in6_setmaxmtu(); /* check all interfaces just in case */ 237 238 #undef MIN 239 } 240 241 void 242 nd6_option_init(opt, icmp6len, ndopts) 243 void *opt; 244 int icmp6len; 245 union nd_opts *ndopts; 246 { 247 248 bzero(ndopts, sizeof(*ndopts)); 249 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 250 ndopts->nd_opts_last 251 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 252 253 if (icmp6len == 0) { 254 ndopts->nd_opts_done = 1; 255 ndopts->nd_opts_search = NULL; 256 } 257 } 258 259 /* 260 * Take one ND option. 261 */ 262 struct nd_opt_hdr * 263 nd6_option(ndopts) 264 union nd_opts *ndopts; 265 { 266 struct nd_opt_hdr *nd_opt; 267 int olen; 268 269 if (ndopts == NULL) 270 panic("ndopts == NULL in nd6_option"); 271 if (ndopts->nd_opts_last == NULL) 272 panic("uninitialized ndopts in nd6_option"); 273 if (ndopts->nd_opts_search == NULL) 274 return NULL; 275 if (ndopts->nd_opts_done) 276 return NULL; 277 278 nd_opt = ndopts->nd_opts_search; 279 280 /* make sure nd_opt_len is inside the buffer */ 281 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { 282 bzero(ndopts, sizeof(*ndopts)); 283 return NULL; 284 } 285 286 olen = nd_opt->nd_opt_len << 3; 287 if (olen == 0) { 288 /* 289 * Message validation requires that all included 290 * options have a length that is greater than zero. 291 */ 292 bzero(ndopts, sizeof(*ndopts)); 293 return NULL; 294 } 295 296 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); 297 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 298 /* option overruns the end of buffer, invalid */ 299 bzero(ndopts, sizeof(*ndopts)); 300 return NULL; 301 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 302 /* reached the end of options chain */ 303 ndopts->nd_opts_done = 1; 304 ndopts->nd_opts_search = NULL; 305 } 306 return nd_opt; 307 } 308 309 /* 310 * Parse multiple ND options. 311 * This function is much easier to use, for ND routines that do not need 312 * multiple options of the same type. 313 */ 314 int 315 nd6_options(ndopts) 316 union nd_opts *ndopts; 317 { 318 struct nd_opt_hdr *nd_opt; 319 int i = 0; 320 321 if (ndopts == NULL) 322 panic("ndopts == NULL in nd6_options"); 323 if (ndopts->nd_opts_last == NULL) 324 panic("uninitialized ndopts in nd6_options"); 325 if (ndopts->nd_opts_search == NULL) 326 return 0; 327 328 while (1) { 329 nd_opt = nd6_option(ndopts); 330 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 331 /* 332 * Message validation requires that all included 333 * options have a length that is greater than zero. 334 */ 335 icmp6stat.icp6s_nd_badopt++; 336 bzero(ndopts, sizeof(*ndopts)); 337 return -1; 338 } 339 340 if (nd_opt == NULL) 341 goto skip1; 342 343 switch (nd_opt->nd_opt_type) { 344 case ND_OPT_SOURCE_LINKADDR: 345 case ND_OPT_TARGET_LINKADDR: 346 case ND_OPT_MTU: 347 case ND_OPT_REDIRECTED_HEADER: 348 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 349 nd6log((LOG_INFO, 350 "duplicated ND6 option found (type=%d)\n", 351 nd_opt->nd_opt_type)); 352 /* XXX bark? */ 353 } else { 354 ndopts->nd_opt_array[nd_opt->nd_opt_type] 355 = nd_opt; 356 } 357 break; 358 case ND_OPT_PREFIX_INFORMATION: 359 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 360 ndopts->nd_opt_array[nd_opt->nd_opt_type] 361 = nd_opt; 362 } 363 ndopts->nd_opts_pi_end = 364 (struct nd_opt_prefix_info *)nd_opt; 365 break; 366 default: 367 /* 368 * Unknown options must be silently ignored, 369 * to accomodate future extension to the protocol. 370 */ 371 nd6log((LOG_DEBUG, 372 "nd6_options: unsupported option %d - " 373 "option ignored\n", nd_opt->nd_opt_type)); 374 } 375 376 skip1: 377 i++; 378 if (i > nd6_maxndopt) { 379 icmp6stat.icp6s_nd_toomanyopt++; 380 nd6log((LOG_INFO, "too many loop in nd opt\n")); 381 break; 382 } 383 384 if (ndopts->nd_opts_done) 385 break; 386 } 387 388 return 0; 389 } 390 391 /* 392 * ND6 timer routine to handle ND6 entries 393 */ 394 void 395 nd6_llinfo_settimer(ln, tick) 396 struct llinfo_nd6 *ln; 397 long tick; 398 { 399 if (tick < 0) { 400 ln->ln_expire = 0; 401 ln->ln_ntick = 0; 402 callout_stop(&ln->ln_timer_ch); 403 } else { 404 ln->ln_expire = time_second + tick / hz; 405 if (tick > INT_MAX) { 406 ln->ln_ntick = tick - INT_MAX; 407 callout_reset(&ln->ln_timer_ch, INT_MAX, 408 nd6_llinfo_timer, ln); 409 } else { 410 ln->ln_ntick = 0; 411 callout_reset(&ln->ln_timer_ch, tick, 412 nd6_llinfo_timer, ln); 413 } 414 } 415 } 416 417 static void 418 nd6_llinfo_timer(arg) 419 void *arg; 420 { 421 struct llinfo_nd6 *ln; 422 struct rtentry *rt; 423 struct in6_addr *dst; 424 struct ifnet *ifp; 425 struct nd_ifinfo *ndi = NULL; 426 427 ln = (struct llinfo_nd6 *)arg; 428 429 if (ln->ln_ntick > 0) { 430 if (ln->ln_ntick > INT_MAX) { 431 ln->ln_ntick -= INT_MAX; 432 nd6_llinfo_settimer(ln, INT_MAX); 433 } else { 434 ln->ln_ntick = 0; 435 nd6_llinfo_settimer(ln, ln->ln_ntick); 436 } 437 return; 438 } 439 440 if ((rt = ln->ln_rt) == NULL) 441 panic("ln->ln_rt == NULL"); 442 if ((ifp = rt->rt_ifp) == NULL) 443 panic("ln->ln_rt->rt_ifp == NULL"); 444 ndi = ND_IFINFO(ifp); 445 446 /* sanity check */ 447 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln) 448 panic("rt_llinfo(%p) is not equal to ln(%p)", 449 rt->rt_llinfo, ln); 450 if (rt_key(rt) == NULL) 451 panic("rt key is NULL in nd6_timer(ln=%p)", ln); 452 453 dst = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 454 455 switch (ln->ln_state) { 456 case ND6_LLINFO_INCOMPLETE: 457 if (ln->ln_asked < nd6_mmaxtries) { 458 ln->ln_asked++; 459 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 460 nd6_ns_output(ifp, NULL, dst, ln, 0); 461 } else { 462 struct mbuf *m = ln->ln_hold; 463 if (m) { 464 struct mbuf *m0; 465 466 /* 467 * assuming every packet in ln_hold has the 468 * same IP header 469 */ 470 m0 = m->m_nextpkt; 471 m->m_nextpkt = NULL; 472 icmp6_error2(m, ICMP6_DST_UNREACH, 473 ICMP6_DST_UNREACH_ADDR, 0, rt->rt_ifp); 474 475 ln->ln_hold = m0; 476 clear_llinfo_pqueue(ln); 477 } 478 if (rt) 479 (void)nd6_free(rt, 0); 480 ln = NULL; 481 } 482 break; 483 case ND6_LLINFO_REACHABLE: 484 if (!ND6_LLINFO_PERMANENT(ln)) { 485 ln->ln_state = ND6_LLINFO_STALE; 486 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 487 } 488 break; 489 490 case ND6_LLINFO_STALE: 491 /* Garbage Collection(RFC 2461 5.3) */ 492 if (!ND6_LLINFO_PERMANENT(ln)) { 493 (void)nd6_free(rt, 1); 494 ln = NULL; 495 } 496 break; 497 498 case ND6_LLINFO_DELAY: 499 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 500 /* We need NUD */ 501 ln->ln_asked = 1; 502 ln->ln_state = ND6_LLINFO_PROBE; 503 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 504 nd6_ns_output(ifp, dst, dst, ln, 0); 505 } else { 506 ln->ln_state = ND6_LLINFO_STALE; /* XXX */ 507 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 508 } 509 break; 510 case ND6_LLINFO_PROBE: 511 if (ln->ln_asked < nd6_umaxtries) { 512 ln->ln_asked++; 513 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 514 nd6_ns_output(ifp, dst, dst, ln, 0); 515 } else { 516 (void)nd6_free(rt, 0); 517 ln = NULL; 518 } 519 break; 520 } 521 } 522 523 524 /* 525 * ND6 timer routine to expire default route list and prefix list 526 */ 527 void 528 nd6_timer(ignored_arg) 529 void *ignored_arg; 530 { 531 int s; 532 struct nd_defrouter *dr; 533 struct nd_prefix *pr; 534 struct in6_ifaddr *ia6, *nia6; 535 struct in6_addrlifetime *lt6; 536 537 callout_reset(&nd6_timer_ch, nd6_prune * hz, 538 nd6_timer, NULL); 539 540 /* expire default router list */ 541 s = splnet(); 542 dr = TAILQ_FIRST(&nd_defrouter); 543 while (dr) { 544 if (dr->expire && dr->expire < time_second) { 545 struct nd_defrouter *t; 546 t = TAILQ_NEXT(dr, dr_entry); 547 defrtrlist_del(dr); 548 dr = t; 549 } else { 550 dr = TAILQ_NEXT(dr, dr_entry); 551 } 552 } 553 554 /* 555 * expire interface addresses. 556 * in the past the loop was inside prefix expiry processing. 557 * However, from a stricter speci-confrmance standpoint, we should 558 * rather separate address lifetimes and prefix lifetimes. 559 */ 560 addrloop: 561 for (ia6 = in6_ifaddr; ia6; ia6 = nia6) { 562 nia6 = ia6->ia_next; 563 /* check address lifetime */ 564 lt6 = &ia6->ia6_lifetime; 565 if (IFA6_IS_INVALID(ia6)) { 566 int regen = 0; 567 568 /* 569 * If the expiring address is temporary, try 570 * regenerating a new one. This would be useful when 571 * we suspended a laptop PC, then turned it on after a 572 * period that could invalidate all temporary 573 * addresses. Although we may have to restart the 574 * loop (see below), it must be after purging the 575 * address. Otherwise, we'd see an infinite loop of 576 * regeneration. 577 */ 578 if (ip6_use_tempaddr && 579 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 580 if (regen_tmpaddr(ia6) == 0) 581 regen = 1; 582 } 583 584 in6_purgeaddr(&ia6->ia_ifa); 585 586 if (regen) 587 goto addrloop; /* XXX: see below */ 588 } else if (IFA6_IS_DEPRECATED(ia6)) { 589 int oldflags = ia6->ia6_flags; 590 591 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 592 593 /* 594 * If a temporary address has just become deprecated, 595 * regenerate a new one if possible. 596 */ 597 if (ip6_use_tempaddr && 598 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 599 (oldflags & IN6_IFF_DEPRECATED) == 0) { 600 601 if (regen_tmpaddr(ia6) == 0) { 602 /* 603 * A new temporary address is 604 * generated. 605 * XXX: this means the address chain 606 * has changed while we are still in 607 * the loop. Although the change 608 * would not cause disaster (because 609 * it's not a deletion, but an 610 * addition,) we'd rather restart the 611 * loop just for safety. Or does this 612 * significantly reduce performance?? 613 */ 614 goto addrloop; 615 } 616 } 617 } else { 618 /* 619 * A new RA might have made a deprecated address 620 * preferred. 621 */ 622 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 623 } 624 } 625 626 /* expire prefix list */ 627 pr = nd_prefix.lh_first; 628 while (pr) { 629 /* 630 * check prefix lifetime. 631 * since pltime is just for autoconf, pltime processing for 632 * prefix is not necessary. 633 */ 634 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && 635 time_second - pr->ndpr_lastupdate > pr->ndpr_vltime) { 636 struct nd_prefix *t; 637 t = pr->ndpr_next; 638 639 /* 640 * address expiration and prefix expiration are 641 * separate. NEVER perform in6_purgeaddr here. 642 */ 643 644 prelist_remove(pr); 645 pr = t; 646 } else 647 pr = pr->ndpr_next; 648 } 649 splx(s); 650 } 651 652 static int 653 regen_tmpaddr(ia6) 654 struct in6_ifaddr *ia6; /* deprecated/invalidated temporary address */ 655 { 656 struct ifaddr *ifa; 657 struct ifnet *ifp; 658 struct in6_ifaddr *public_ifa6 = NULL; 659 660 ifp = ia6->ia_ifa.ifa_ifp; 661 for (ifa = ifp->if_addrlist.tqh_first; ifa; 662 ifa = ifa->ifa_list.tqe_next) { 663 struct in6_ifaddr *it6; 664 665 if (ifa->ifa_addr->sa_family != AF_INET6) 666 continue; 667 668 it6 = (struct in6_ifaddr *)ifa; 669 670 /* ignore no autoconf addresses. */ 671 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 672 continue; 673 674 /* ignore autoconf addresses with different prefixes. */ 675 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 676 continue; 677 678 /* 679 * Now we are looking at an autoconf address with the same 680 * prefix as ours. If the address is temporary and is still 681 * preferred, do not create another one. It would be rare, but 682 * could happen, for example, when we resume a laptop PC after 683 * a long period. 684 */ 685 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 686 !IFA6_IS_DEPRECATED(it6)) { 687 public_ifa6 = NULL; 688 break; 689 } 690 691 /* 692 * This is a public autoconf address that has the same prefix 693 * as ours. If it is preferred, keep it. We can't break the 694 * loop here, because there may be a still-preferred temporary 695 * address with the prefix. 696 */ 697 if (!IFA6_IS_DEPRECATED(it6)) 698 public_ifa6 = it6; 699 } 700 701 if (public_ifa6 != NULL) { 702 int e; 703 704 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 705 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 706 " tmp addr,errno=%d\n", e); 707 return (-1); 708 } 709 return (0); 710 } 711 712 return (-1); 713 } 714 715 /* 716 * Nuke neighbor cache/prefix/default router management table, right before 717 * ifp goes away. 718 */ 719 void 720 nd6_purge(ifp) 721 struct ifnet *ifp; 722 { 723 struct llinfo_nd6 *ln, *nln; 724 struct nd_defrouter *dr, *ndr; 725 struct nd_prefix *pr, *npr; 726 727 /* 728 * Nuke default router list entries toward ifp. 729 * We defer removal of default router list entries that is installed 730 * in the routing table, in order to keep additional side effects as 731 * small as possible. 732 */ 733 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 734 ndr = TAILQ_NEXT(dr, dr_entry); 735 if (dr->installed) 736 continue; 737 738 if (dr->ifp == ifp) 739 defrtrlist_del(dr); 740 } 741 742 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 743 ndr = TAILQ_NEXT(dr, dr_entry); 744 if (!dr->installed) 745 continue; 746 747 if (dr->ifp == ifp) 748 defrtrlist_del(dr); 749 } 750 751 /* Nuke prefix list entries toward ifp */ 752 for (pr = nd_prefix.lh_first; pr; pr = npr) { 753 npr = pr->ndpr_next; 754 if (pr->ndpr_ifp == ifp) { 755 /* 756 * Because if_detach() does *not* release prefixes 757 * while purging addresses the reference count will 758 * still be above zero. We therefore reset it to 759 * make sure that the prefix really gets purged. 760 */ 761 pr->ndpr_refcnt = 0; 762 763 /* 764 * Previously, pr->ndpr_addr is removed as well, 765 * but I strongly believe we don't have to do it. 766 * nd6_purge() is only called from in6_ifdetach(), 767 * which removes all the associated interface addresses 768 * by itself. 769 * (jinmei@kame.net 20010129) 770 */ 771 prelist_remove(pr); 772 } 773 } 774 775 /* cancel default outgoing interface setting */ 776 if (nd6_defifindex == ifp->if_index) 777 nd6_setdefaultiface(0); 778 779 if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */ 780 /* refresh default router list */ 781 defrouter_select(); 782 } 783 784 /* 785 * Nuke neighbor cache entries for the ifp. 786 * Note that rt->rt_ifp may not be the same as ifp, 787 * due to KAME goto ours hack. See RTM_RESOLVE case in 788 * nd6_rtrequest(), and ip6_input(). 789 */ 790 ln = llinfo_nd6.ln_next; 791 while (ln && ln != &llinfo_nd6) { 792 struct rtentry *rt; 793 struct sockaddr_dl *sdl; 794 795 nln = ln->ln_next; 796 rt = ln->ln_rt; 797 if (rt && rt->rt_gateway && 798 rt->rt_gateway->sa_family == AF_LINK) { 799 sdl = (struct sockaddr_dl *)rt->rt_gateway; 800 if (sdl->sdl_index == ifp->if_index) 801 nln = nd6_free(rt, 0); 802 } 803 ln = nln; 804 } 805 } 806 807 struct rtentry * 808 nd6_lookup(addr6, create, ifp) 809 struct in6_addr *addr6; 810 int create; 811 struct ifnet *ifp; 812 { 813 struct rtentry *rt; 814 struct sockaddr_in6 sin6; 815 816 bzero(&sin6, sizeof(sin6)); 817 sin6.sin6_len = sizeof(struct sockaddr_in6); 818 sin6.sin6_family = AF_INET6; 819 sin6.sin6_addr = *addr6; 820 rt = rtalloc1((struct sockaddr *)&sin6, create, 0UL); 821 if (rt) { 822 if ((rt->rt_flags & RTF_LLINFO) == 0 && create) { 823 /* 824 * This is the case for the default route. 825 * If we want to create a neighbor cache for the 826 * address, we should free the route for the 827 * destination and allocate an interface route. 828 */ 829 RTFREE_LOCKED(rt); 830 rt = NULL; 831 } 832 } 833 if (rt == NULL) { 834 if (create && ifp) { 835 int e; 836 837 /* 838 * If no route is available and create is set, 839 * we allocate a host route for the destination 840 * and treat it like an interface route. 841 * This hack is necessary for a neighbor which can't 842 * be covered by our own prefix. 843 */ 844 struct ifaddr *ifa = 845 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp); 846 if (ifa == NULL) 847 return (NULL); 848 849 /* 850 * Create a new route. RTF_LLINFO is necessary 851 * to create a Neighbor Cache entry for the 852 * destination in nd6_rtrequest which will be 853 * called in rtrequest via ifa->ifa_rtrequest. 854 */ 855 if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6, 856 ifa->ifa_addr, (struct sockaddr *)&all1_sa, 857 (ifa->ifa_flags | RTF_HOST | RTF_LLINFO) & 858 ~RTF_CLONING, &rt)) != 0) { 859 log(LOG_ERR, 860 "nd6_lookup: failed to add route for a " 861 "neighbor(%s), errno=%d\n", 862 ip6_sprintf(addr6), e); 863 } 864 if (rt == NULL) 865 return (NULL); 866 RT_LOCK(rt); 867 if (rt->rt_llinfo) { 868 struct llinfo_nd6 *ln = 869 (struct llinfo_nd6 *)rt->rt_llinfo; 870 ln->ln_state = ND6_LLINFO_NOSTATE; 871 } 872 } else 873 return (NULL); 874 } 875 RT_LOCK_ASSERT(rt); 876 RT_REMREF(rt); 877 /* 878 * Validation for the entry. 879 * Note that the check for rt_llinfo is necessary because a cloned 880 * route from a parent route that has the L flag (e.g. the default 881 * route to a p2p interface) may have the flag, too, while the 882 * destination is not actually a neighbor. 883 * XXX: we can't use rt->rt_ifp to check for the interface, since 884 * it might be the loopback interface if the entry is for our 885 * own address on a non-loopback interface. Instead, we should 886 * use rt->rt_ifa->ifa_ifp, which would specify the REAL 887 * interface. 888 * Note also that ifa_ifp and ifp may differ when we connect two 889 * interfaces to a same link, install a link prefix to an interface, 890 * and try to install a neighbor cache on an interface that does not 891 * have a route to the prefix. 892 */ 893 if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 || 894 rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL || 895 (ifp && rt->rt_ifa->ifa_ifp != ifp)) { 896 if (create) { 897 nd6log((LOG_DEBUG, 898 "nd6_lookup: failed to lookup %s (if = %s)\n", 899 ip6_sprintf(addr6), 900 ifp ? if_name(ifp) : "unspec")); 901 } 902 RT_UNLOCK(rt); 903 return (NULL); 904 } 905 RT_UNLOCK(rt); /* XXX not ready to return rt locked */ 906 return (rt); 907 } 908 909 /* 910 * Test whether a given IPv6 address is a neighbor or not, ignoring 911 * the actual neighbor cache. The neighbor cache is ignored in order 912 * to not reenter the routing code from within itself. 913 */ 914 static int 915 nd6_is_new_addr_neighbor(addr, ifp) 916 struct sockaddr_in6 *addr; 917 struct ifnet *ifp; 918 { 919 struct nd_prefix *pr; 920 struct ifaddr *dstaddr; 921 922 /* 923 * A link-local address is always a neighbor. 924 * XXX: a link does not necessarily specify a single interface. 925 */ 926 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 927 struct sockaddr_in6 sin6_copy; 928 u_int32_t zone; 929 930 /* 931 * We need sin6_copy since sa6_recoverscope() may modify the 932 * content (XXX). 933 */ 934 sin6_copy = *addr; 935 if (sa6_recoverscope(&sin6_copy)) 936 return (0); /* XXX: should be impossible */ 937 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 938 return (0); 939 if (sin6_copy.sin6_scope_id == zone) 940 return (1); 941 else 942 return (0); 943 } 944 945 /* 946 * If the address matches one of our addresses, 947 * it should be a neighbor. 948 * If the address matches one of our on-link prefixes, it should be a 949 * neighbor. 950 */ 951 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 952 if (pr->ndpr_ifp != ifp) 953 continue; 954 955 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) 956 continue; 957 958 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 959 &addr->sin6_addr, &pr->ndpr_mask)) 960 return (1); 961 } 962 963 /* 964 * If the address is assigned on the node of the other side of 965 * a p2p interface, the address should be a neighbor. 966 */ 967 dstaddr = ifa_ifwithdstaddr((struct sockaddr *)addr); 968 if ((dstaddr != NULL) && (dstaddr->ifa_ifp == ifp)) 969 return (1); 970 971 /* 972 * If the default router list is empty, all addresses are regarded 973 * as on-link, and thus, as a neighbor. 974 * XXX: we restrict the condition to hosts, because routers usually do 975 * not have the "default router list". 976 */ 977 if (!ip6_forwarding && TAILQ_FIRST(&nd_defrouter) == NULL && 978 nd6_defifindex == ifp->if_index) { 979 return (1); 980 } 981 982 return (0); 983 } 984 985 986 /* 987 * Detect if a given IPv6 address identifies a neighbor on a given link. 988 * XXX: should take care of the destination of a p2p link? 989 */ 990 int 991 nd6_is_addr_neighbor(addr, ifp) 992 struct sockaddr_in6 *addr; 993 struct ifnet *ifp; 994 { 995 996 if (nd6_is_new_addr_neighbor(addr, ifp)) 997 return (1); 998 999 /* 1000 * Even if the address matches none of our addresses, it might be 1001 * in the neighbor cache. 1002 */ 1003 if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL) 1004 return (1); 1005 1006 return (0); 1007 } 1008 1009 /* 1010 * Free an nd6 llinfo entry. 1011 * Since the function would cause significant changes in the kernel, DO NOT 1012 * make it global, unless you have a strong reason for the change, and are sure 1013 * that the change is safe. 1014 */ 1015 static struct llinfo_nd6 * 1016 nd6_free(rt, gc) 1017 struct rtentry *rt; 1018 int gc; 1019 { 1020 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next; 1021 struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 1022 struct nd_defrouter *dr; 1023 1024 /* 1025 * we used to have pfctlinput(PRC_HOSTDEAD) here. 1026 * even though it is not harmful, it was not really necessary. 1027 */ 1028 1029 /* cancel timer */ 1030 nd6_llinfo_settimer(ln, -1); 1031 1032 if (!ip6_forwarding) { 1033 int s; 1034 s = splnet(); 1035 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr, 1036 rt->rt_ifp); 1037 1038 if (dr != NULL && dr->expire && 1039 ln->ln_state == ND6_LLINFO_STALE && gc) { 1040 /* 1041 * If the reason for the deletion is just garbage 1042 * collection, and the neighbor is an active default 1043 * router, do not delete it. Instead, reset the GC 1044 * timer using the router's lifetime. 1045 * Simply deleting the entry would affect default 1046 * router selection, which is not necessarily a good 1047 * thing, especially when we're using router preference 1048 * values. 1049 * XXX: the check for ln_state would be redundant, 1050 * but we intentionally keep it just in case. 1051 */ 1052 if (dr->expire > time_second) 1053 nd6_llinfo_settimer(ln, 1054 (dr->expire - time_second) * hz); 1055 else 1056 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1057 splx(s); 1058 return (ln->ln_next); 1059 } 1060 1061 if (ln->ln_router || dr) { 1062 /* 1063 * rt6_flush must be called whether or not the neighbor 1064 * is in the Default Router List. 1065 * See a corresponding comment in nd6_na_input(). 1066 */ 1067 rt6_flush(&in6, rt->rt_ifp); 1068 } 1069 1070 if (dr) { 1071 /* 1072 * Unreachablity of a router might affect the default 1073 * router selection and on-link detection of advertised 1074 * prefixes. 1075 */ 1076 1077 /* 1078 * Temporarily fake the state to choose a new default 1079 * router and to perform on-link determination of 1080 * prefixes correctly. 1081 * Below the state will be set correctly, 1082 * or the entry itself will be deleted. 1083 */ 1084 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1085 1086 /* 1087 * Since defrouter_select() does not affect the 1088 * on-link determination and MIP6 needs the check 1089 * before the default router selection, we perform 1090 * the check now. 1091 */ 1092 pfxlist_onlink_check(); 1093 1094 /* 1095 * refresh default router list 1096 */ 1097 defrouter_select(); 1098 } 1099 splx(s); 1100 } 1101 1102 /* 1103 * Before deleting the entry, remember the next entry as the 1104 * return value. We need this because pfxlist_onlink_check() above 1105 * might have freed other entries (particularly the old next entry) as 1106 * a side effect (XXX). 1107 */ 1108 next = ln->ln_next; 1109 1110 /* 1111 * Detach the route from the routing tree and the list of neighbor 1112 * caches, and disable the route entry not to be used in already 1113 * cached routes. 1114 */ 1115 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, 1116 rt_mask(rt), 0, (struct rtentry **)0); 1117 1118 return (next); 1119 } 1120 1121 /* 1122 * Upper-layer reachability hint for Neighbor Unreachability Detection. 1123 * 1124 * XXX cost-effective methods? 1125 */ 1126 void 1127 nd6_nud_hint(rt, dst6, force) 1128 struct rtentry *rt; 1129 struct in6_addr *dst6; 1130 int force; 1131 { 1132 struct llinfo_nd6 *ln; 1133 1134 /* 1135 * If the caller specified "rt", use that. Otherwise, resolve the 1136 * routing table by supplied "dst6". 1137 */ 1138 if (rt == NULL) { 1139 if (dst6 == NULL) 1140 return; 1141 if ((rt = nd6_lookup(dst6, 0, NULL)) == NULL) 1142 return; 1143 } 1144 1145 if ((rt->rt_flags & RTF_GATEWAY) != 0 || 1146 (rt->rt_flags & RTF_LLINFO) == 0 || 1147 rt->rt_llinfo == NULL || rt->rt_gateway == NULL || 1148 rt->rt_gateway->sa_family != AF_LINK) { 1149 /* This is not a host route. */ 1150 return; 1151 } 1152 1153 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1154 if (ln->ln_state < ND6_LLINFO_REACHABLE) 1155 return; 1156 1157 /* 1158 * if we get upper-layer reachability confirmation many times, 1159 * it is possible we have false information. 1160 */ 1161 if (!force) { 1162 ln->ln_byhint++; 1163 if (ln->ln_byhint > nd6_maxnudhint) 1164 return; 1165 } 1166 1167 ln->ln_state = ND6_LLINFO_REACHABLE; 1168 if (!ND6_LLINFO_PERMANENT(ln)) { 1169 nd6_llinfo_settimer(ln, 1170 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 1171 } 1172 } 1173 1174 void 1175 nd6_rtrequest(req, rt, info) 1176 int req; 1177 struct rtentry *rt; 1178 struct rt_addrinfo *info; /* xxx unused */ 1179 { 1180 struct sockaddr *gate = rt->rt_gateway; 1181 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1182 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 1183 struct ifnet *ifp = rt->rt_ifp; 1184 struct ifaddr *ifa; 1185 1186 RT_LOCK_ASSERT(rt); 1187 1188 if ((rt->rt_flags & RTF_GATEWAY) != 0) 1189 return; 1190 1191 if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) { 1192 /* 1193 * This is probably an interface direct route for a link 1194 * which does not need neighbor caches (e.g. fe80::%lo0/64). 1195 * We do not need special treatment below for such a route. 1196 * Moreover, the RTF_LLINFO flag which would be set below 1197 * would annoy the ndp(8) command. 1198 */ 1199 return; 1200 } 1201 1202 if (req == RTM_RESOLVE && 1203 (nd6_need_cache(ifp) == 0 || /* stf case */ 1204 !nd6_is_new_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), 1205 ifp))) { 1206 /* 1207 * FreeBSD and BSD/OS often make a cloned host route based 1208 * on a less-specific route (e.g. the default route). 1209 * If the less specific route does not have a "gateway" 1210 * (this is the case when the route just goes to a p2p or an 1211 * stf interface), we'll mistakenly make a neighbor cache for 1212 * the host route, and will see strange neighbor solicitation 1213 * for the corresponding destination. In order to avoid the 1214 * confusion, we check if the destination of the route is 1215 * a neighbor in terms of neighbor discovery, and stop the 1216 * process if not. Additionally, we remove the LLINFO flag 1217 * so that ndp(8) will not try to get the neighbor information 1218 * of the destination. 1219 */ 1220 rt->rt_flags &= ~RTF_LLINFO; 1221 return; 1222 } 1223 1224 switch (req) { 1225 case RTM_ADD: 1226 /* 1227 * There is no backward compatibility :) 1228 * 1229 * if ((rt->rt_flags & RTF_HOST) == 0 && 1230 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 1231 * rt->rt_flags |= RTF_CLONING; 1232 */ 1233 if ((rt->rt_flags & RTF_CLONING) || 1234 ((rt->rt_flags & RTF_LLINFO) && ln == NULL)) { 1235 /* 1236 * Case 1: This route should come from a route to 1237 * interface (RTF_CLONING case) or the route should be 1238 * treated as on-link but is currently not 1239 * (RTF_LLINFO && ln == NULL case). 1240 */ 1241 rt_setgate(rt, rt_key(rt), 1242 (struct sockaddr *)&null_sdl); 1243 gate = rt->rt_gateway; 1244 SDL(gate)->sdl_type = ifp->if_type; 1245 SDL(gate)->sdl_index = ifp->if_index; 1246 if (ln) 1247 nd6_llinfo_settimer(ln, 0); 1248 if ((rt->rt_flags & RTF_CLONING) != 0) 1249 break; 1250 } 1251 /* 1252 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here. 1253 * We don't do that here since llinfo is not ready yet. 1254 * 1255 * There are also couple of other things to be discussed: 1256 * - unsolicited NA code needs improvement beforehand 1257 * - RFC2461 says we MAY send multicast unsolicited NA 1258 * (7.2.6 paragraph 4), however, it also says that we 1259 * SHOULD provide a mechanism to prevent multicast NA storm. 1260 * we don't have anything like it right now. 1261 * note that the mechanism needs a mutual agreement 1262 * between proxies, which means that we need to implement 1263 * a new protocol, or a new kludge. 1264 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA. 1265 * we need to check ip6forwarding before sending it. 1266 * (or should we allow proxy ND configuration only for 1267 * routers? there's no mention about proxy ND from hosts) 1268 */ 1269 /* FALLTHROUGH */ 1270 case RTM_RESOLVE: 1271 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) { 1272 /* 1273 * Address resolution isn't necessary for a point to 1274 * point link, so we can skip this test for a p2p link. 1275 */ 1276 if (gate->sa_family != AF_LINK || 1277 gate->sa_len < sizeof(null_sdl)) { 1278 log(LOG_DEBUG, 1279 "nd6_rtrequest: bad gateway value: %s\n", 1280 if_name(ifp)); 1281 break; 1282 } 1283 SDL(gate)->sdl_type = ifp->if_type; 1284 SDL(gate)->sdl_index = ifp->if_index; 1285 } 1286 if (ln != NULL) 1287 break; /* This happens on a route change */ 1288 /* 1289 * Case 2: This route may come from cloning, or a manual route 1290 * add with a LL address. 1291 */ 1292 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln)); 1293 rt->rt_llinfo = (caddr_t)ln; 1294 if (ln == NULL) { 1295 log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n"); 1296 break; 1297 } 1298 nd6_inuse++; 1299 nd6_allocated++; 1300 bzero(ln, sizeof(*ln)); 1301 ln->ln_rt = rt; 1302 callout_init(&ln->ln_timer_ch, 0); 1303 1304 /* this is required for "ndp" command. - shin */ 1305 if (req == RTM_ADD) { 1306 /* 1307 * gate should have some valid AF_LINK entry, 1308 * and ln->ln_expire should have some lifetime 1309 * which is specified by ndp command. 1310 */ 1311 ln->ln_state = ND6_LLINFO_REACHABLE; 1312 ln->ln_byhint = 0; 1313 } else { 1314 /* 1315 * When req == RTM_RESOLVE, rt is created and 1316 * initialized in rtrequest(), so rt_expire is 0. 1317 */ 1318 ln->ln_state = ND6_LLINFO_NOSTATE; 1319 nd6_llinfo_settimer(ln, 0); 1320 } 1321 rt->rt_flags |= RTF_LLINFO; 1322 ln->ln_next = llinfo_nd6.ln_next; 1323 llinfo_nd6.ln_next = ln; 1324 ln->ln_prev = &llinfo_nd6; 1325 ln->ln_next->ln_prev = ln; 1326 1327 /* 1328 * check if rt_key(rt) is one of my address assigned 1329 * to the interface. 1330 */ 1331 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp, 1332 &SIN6(rt_key(rt))->sin6_addr); 1333 if (ifa) { 1334 caddr_t macp = nd6_ifptomac(ifp); 1335 nd6_llinfo_settimer(ln, -1); 1336 ln->ln_state = ND6_LLINFO_REACHABLE; 1337 ln->ln_byhint = 0; 1338 if (macp) { 1339 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen); 1340 SDL(gate)->sdl_alen = ifp->if_addrlen; 1341 } 1342 if (nd6_useloopback) { 1343 rt->rt_ifp = &loif[0]; /* XXX */ 1344 /* 1345 * Make sure rt_ifa be equal to the ifaddr 1346 * corresponding to the address. 1347 * We need this because when we refer 1348 * rt_ifa->ia6_flags in ip6_input, we assume 1349 * that the rt_ifa points to the address instead 1350 * of the loopback address. 1351 */ 1352 if (ifa != rt->rt_ifa) { 1353 IFAFREE(rt->rt_ifa); 1354 IFAREF(ifa); 1355 rt->rt_ifa = ifa; 1356 } 1357 } 1358 } else if (rt->rt_flags & RTF_ANNOUNCE) { 1359 nd6_llinfo_settimer(ln, -1); 1360 ln->ln_state = ND6_LLINFO_REACHABLE; 1361 ln->ln_byhint = 0; 1362 1363 /* join solicited node multicast for proxy ND */ 1364 if (ifp->if_flags & IFF_MULTICAST) { 1365 struct in6_addr llsol; 1366 int error; 1367 1368 llsol = SIN6(rt_key(rt))->sin6_addr; 1369 llsol.s6_addr32[0] = IPV6_ADDR_INT32_MLL; 1370 llsol.s6_addr32[1] = 0; 1371 llsol.s6_addr32[2] = htonl(1); 1372 llsol.s6_addr8[12] = 0xff; 1373 if (in6_setscope(&llsol, ifp, NULL)) 1374 break; 1375 if (in6_addmulti(&llsol, ifp, 1376 &error, 0) == NULL) { 1377 nd6log((LOG_ERR, "%s: failed to join " 1378 "%s (errno=%d)\n", if_name(ifp), 1379 ip6_sprintf(&llsol), error)); 1380 } 1381 } 1382 } 1383 break; 1384 1385 case RTM_DELETE: 1386 if (ln == NULL) 1387 break; 1388 /* leave from solicited node multicast for proxy ND */ 1389 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 && 1390 (ifp->if_flags & IFF_MULTICAST) != 0) { 1391 struct in6_addr llsol; 1392 struct in6_multi *in6m; 1393 1394 llsol = SIN6(rt_key(rt))->sin6_addr; 1395 llsol.s6_addr32[0] = IPV6_ADDR_INT32_MLL; 1396 llsol.s6_addr32[1] = 0; 1397 llsol.s6_addr32[2] = htonl(1); 1398 llsol.s6_addr8[12] = 0xff; 1399 if (in6_setscope(&llsol, ifp, NULL) == 0) { 1400 IN6_LOOKUP_MULTI(llsol, ifp, in6m); 1401 if (in6m) 1402 in6_delmulti(in6m); 1403 } else 1404 ; /* XXX: should not happen. bark here? */ 1405 } 1406 nd6_inuse--; 1407 ln->ln_next->ln_prev = ln->ln_prev; 1408 ln->ln_prev->ln_next = ln->ln_next; 1409 ln->ln_prev = NULL; 1410 nd6_llinfo_settimer(ln, -1); 1411 rt->rt_llinfo = 0; 1412 rt->rt_flags &= ~RTF_LLINFO; 1413 clear_llinfo_pqueue(ln); 1414 Free((caddr_t)ln); 1415 } 1416 } 1417 1418 int 1419 nd6_ioctl(cmd, data, ifp) 1420 u_long cmd; 1421 caddr_t data; 1422 struct ifnet *ifp; 1423 { 1424 struct in6_drlist *drl = (struct in6_drlist *)data; 1425 struct in6_oprlist *oprl = (struct in6_oprlist *)data; 1426 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1427 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1428 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1429 struct nd_defrouter *dr; 1430 struct nd_prefix *pr; 1431 struct rtentry *rt; 1432 int i = 0, error = 0; 1433 int s; 1434 1435 switch (cmd) { 1436 case SIOCGDRLST_IN6: 1437 /* 1438 * obsolete API, use sysctl under net.inet6.icmp6 1439 */ 1440 bzero(drl, sizeof(*drl)); 1441 s = splnet(); 1442 dr = TAILQ_FIRST(&nd_defrouter); 1443 while (dr && i < DRLSTSIZ) { 1444 drl->defrouter[i].rtaddr = dr->rtaddr; 1445 in6_clearscope(&drl->defrouter[i].rtaddr); 1446 1447 drl->defrouter[i].flags = dr->flags; 1448 drl->defrouter[i].rtlifetime = dr->rtlifetime; 1449 drl->defrouter[i].expire = dr->expire; 1450 drl->defrouter[i].if_index = dr->ifp->if_index; 1451 i++; 1452 dr = TAILQ_NEXT(dr, dr_entry); 1453 } 1454 splx(s); 1455 break; 1456 case SIOCGPRLST_IN6: 1457 /* 1458 * obsolete API, use sysctl under net.inet6.icmp6 1459 * 1460 * XXX the structure in6_prlist was changed in backward- 1461 * incompatible manner. in6_oprlist is used for SIOCGPRLST_IN6, 1462 * in6_prlist is used for nd6_sysctl() - fill_prlist(). 1463 */ 1464 /* 1465 * XXX meaning of fields, especialy "raflags", is very 1466 * differnet between RA prefix list and RR/static prefix list. 1467 * how about separating ioctls into two? 1468 */ 1469 bzero(oprl, sizeof(*oprl)); 1470 s = splnet(); 1471 pr = nd_prefix.lh_first; 1472 while (pr && i < PRLSTSIZ) { 1473 struct nd_pfxrouter *pfr; 1474 int j; 1475 1476 oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr; 1477 oprl->prefix[i].raflags = pr->ndpr_raf; 1478 oprl->prefix[i].prefixlen = pr->ndpr_plen; 1479 oprl->prefix[i].vltime = pr->ndpr_vltime; 1480 oprl->prefix[i].pltime = pr->ndpr_pltime; 1481 oprl->prefix[i].if_index = pr->ndpr_ifp->if_index; 1482 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1483 oprl->prefix[i].expire = 0; 1484 else { 1485 time_t maxexpire; 1486 1487 /* XXX: we assume time_t is signed. */ 1488 maxexpire = (-1) & 1489 ~((time_t)1 << 1490 ((sizeof(maxexpire) * 8) - 1)); 1491 if (pr->ndpr_vltime < 1492 maxexpire - pr->ndpr_lastupdate) { 1493 oprl->prefix[i].expire = 1494 pr->ndpr_lastupdate + 1495 pr->ndpr_vltime; 1496 } else 1497 oprl->prefix[i].expire = maxexpire; 1498 } 1499 1500 pfr = pr->ndpr_advrtrs.lh_first; 1501 j = 0; 1502 while (pfr) { 1503 if (j < DRLSTSIZ) { 1504 #define RTRADDR oprl->prefix[i].advrtr[j] 1505 RTRADDR = pfr->router->rtaddr; 1506 in6_clearscope(&RTRADDR); 1507 #undef RTRADDR 1508 } 1509 j++; 1510 pfr = pfr->pfr_next; 1511 } 1512 oprl->prefix[i].advrtrs = j; 1513 oprl->prefix[i].origin = PR_ORIG_RA; 1514 1515 i++; 1516 pr = pr->ndpr_next; 1517 } 1518 splx(s); 1519 1520 break; 1521 case OSIOCGIFINFO_IN6: 1522 #define ND ndi->ndi 1523 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1524 bzero(&ND, sizeof(ND)); 1525 ND.linkmtu = IN6_LINKMTU(ifp); 1526 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1527 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1528 ND.reachable = ND_IFINFO(ifp)->reachable; 1529 ND.retrans = ND_IFINFO(ifp)->retrans; 1530 ND.flags = ND_IFINFO(ifp)->flags; 1531 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1532 ND.chlim = ND_IFINFO(ifp)->chlim; 1533 break; 1534 case SIOCGIFINFO_IN6: 1535 ND = *ND_IFINFO(ifp); 1536 break; 1537 case SIOCSIFINFO_IN6: 1538 /* 1539 * used to change host variables from userland. 1540 * intented for a use on router to reflect RA configurations. 1541 */ 1542 /* 0 means 'unspecified' */ 1543 if (ND.linkmtu != 0) { 1544 if (ND.linkmtu < IPV6_MMTU || 1545 ND.linkmtu > IN6_LINKMTU(ifp)) { 1546 error = EINVAL; 1547 break; 1548 } 1549 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1550 } 1551 1552 if (ND.basereachable != 0) { 1553 int obasereachable = ND_IFINFO(ifp)->basereachable; 1554 1555 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1556 if (ND.basereachable != obasereachable) 1557 ND_IFINFO(ifp)->reachable = 1558 ND_COMPUTE_RTIME(ND.basereachable); 1559 } 1560 if (ND.retrans != 0) 1561 ND_IFINFO(ifp)->retrans = ND.retrans; 1562 if (ND.chlim != 0) 1563 ND_IFINFO(ifp)->chlim = ND.chlim; 1564 /* FALLTHROUGH */ 1565 case SIOCSIFINFO_FLAGS: 1566 ND_IFINFO(ifp)->flags = ND.flags; 1567 break; 1568 #undef ND 1569 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1570 /* sync kernel routing table with the default router list */ 1571 defrouter_reset(); 1572 defrouter_select(); 1573 break; 1574 case SIOCSPFXFLUSH_IN6: 1575 { 1576 /* flush all the prefix advertised by routers */ 1577 struct nd_prefix *pr, *next; 1578 1579 s = splnet(); 1580 for (pr = nd_prefix.lh_first; pr; pr = next) { 1581 struct in6_ifaddr *ia, *ia_next; 1582 1583 next = pr->ndpr_next; 1584 1585 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1586 continue; /* XXX */ 1587 1588 /* do we really have to remove addresses as well? */ 1589 for (ia = in6_ifaddr; ia; ia = ia_next) { 1590 /* ia might be removed. keep the next ptr. */ 1591 ia_next = ia->ia_next; 1592 1593 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1594 continue; 1595 1596 if (ia->ia6_ndpr == pr) 1597 in6_purgeaddr(&ia->ia_ifa); 1598 } 1599 prelist_remove(pr); 1600 } 1601 splx(s); 1602 break; 1603 } 1604 case SIOCSRTRFLUSH_IN6: 1605 { 1606 /* flush all the default routers */ 1607 struct nd_defrouter *dr, *next; 1608 1609 s = splnet(); 1610 defrouter_reset(); 1611 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = next) { 1612 next = TAILQ_NEXT(dr, dr_entry); 1613 defrtrlist_del(dr); 1614 } 1615 defrouter_select(); 1616 splx(s); 1617 break; 1618 } 1619 case SIOCGNBRINFO_IN6: 1620 { 1621 struct llinfo_nd6 *ln; 1622 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1623 1624 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1625 return (error); 1626 1627 s = splnet(); 1628 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL) { 1629 error = EINVAL; 1630 splx(s); 1631 break; 1632 } 1633 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1634 nbi->state = ln->ln_state; 1635 nbi->asked = ln->ln_asked; 1636 nbi->isrouter = ln->ln_router; 1637 nbi->expire = ln->ln_expire; 1638 splx(s); 1639 1640 break; 1641 } 1642 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1643 ndif->ifindex = nd6_defifindex; 1644 break; 1645 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1646 return (nd6_setdefaultiface(ndif->ifindex)); 1647 } 1648 return (error); 1649 } 1650 1651 /* 1652 * Create neighbor cache entry and cache link-layer address, 1653 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1654 */ 1655 struct rtentry * 1656 nd6_cache_lladdr(ifp, from, lladdr, lladdrlen, type, code) 1657 struct ifnet *ifp; 1658 struct in6_addr *from; 1659 char *lladdr; 1660 int lladdrlen; 1661 int type; /* ICMP6 type */ 1662 int code; /* type dependent information */ 1663 { 1664 struct rtentry *rt = NULL; 1665 struct llinfo_nd6 *ln = NULL; 1666 int is_newentry; 1667 struct sockaddr_dl *sdl = NULL; 1668 int do_update; 1669 int olladdr; 1670 int llchange; 1671 int newstate = 0; 1672 1673 if (ifp == NULL) 1674 panic("ifp == NULL in nd6_cache_lladdr"); 1675 if (from == NULL) 1676 panic("from == NULL in nd6_cache_lladdr"); 1677 1678 /* nothing must be updated for unspecified address */ 1679 if (IN6_IS_ADDR_UNSPECIFIED(from)) 1680 return NULL; 1681 1682 /* 1683 * Validation about ifp->if_addrlen and lladdrlen must be done in 1684 * the caller. 1685 * 1686 * XXX If the link does not have link-layer adderss, what should 1687 * we do? (ifp->if_addrlen == 0) 1688 * Spec says nothing in sections for RA, RS and NA. There's small 1689 * description on it in NS section (RFC 2461 7.2.3). 1690 */ 1691 1692 rt = nd6_lookup(from, 0, ifp); 1693 if (rt == NULL) { 1694 rt = nd6_lookup(from, 1, ifp); 1695 is_newentry = 1; 1696 } else { 1697 /* do nothing if static ndp is set */ 1698 if (rt->rt_flags & RTF_STATIC) 1699 return NULL; 1700 is_newentry = 0; 1701 } 1702 1703 if (rt == NULL) 1704 return NULL; 1705 if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) { 1706 fail: 1707 (void)nd6_free(rt, 0); 1708 return NULL; 1709 } 1710 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1711 if (ln == NULL) 1712 goto fail; 1713 if (rt->rt_gateway == NULL) 1714 goto fail; 1715 if (rt->rt_gateway->sa_family != AF_LINK) 1716 goto fail; 1717 sdl = SDL(rt->rt_gateway); 1718 1719 olladdr = (sdl->sdl_alen) ? 1 : 0; 1720 if (olladdr && lladdr) { 1721 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 1722 llchange = 1; 1723 else 1724 llchange = 0; 1725 } else 1726 llchange = 0; 1727 1728 /* 1729 * newentry olladdr lladdr llchange (*=record) 1730 * 0 n n -- (1) 1731 * 0 y n -- (2) 1732 * 0 n y -- (3) * STALE 1733 * 0 y y n (4) * 1734 * 0 y y y (5) * STALE 1735 * 1 -- n -- (6) NOSTATE(= PASSIVE) 1736 * 1 -- y -- (7) * STALE 1737 */ 1738 1739 if (lladdr) { /* (3-5) and (7) */ 1740 /* 1741 * Record source link-layer address 1742 * XXX is it dependent to ifp->if_type? 1743 */ 1744 sdl->sdl_alen = ifp->if_addrlen; 1745 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 1746 } 1747 1748 if (!is_newentry) { 1749 if ((!olladdr && lladdr != NULL) || /* (3) */ 1750 (olladdr && lladdr != NULL && llchange)) { /* (5) */ 1751 do_update = 1; 1752 newstate = ND6_LLINFO_STALE; 1753 } else /* (1-2,4) */ 1754 do_update = 0; 1755 } else { 1756 do_update = 1; 1757 if (lladdr == NULL) /* (6) */ 1758 newstate = ND6_LLINFO_NOSTATE; 1759 else /* (7) */ 1760 newstate = ND6_LLINFO_STALE; 1761 } 1762 1763 if (do_update) { 1764 /* 1765 * Update the state of the neighbor cache. 1766 */ 1767 ln->ln_state = newstate; 1768 1769 if (ln->ln_state == ND6_LLINFO_STALE) { 1770 /* 1771 * XXX: since nd6_output() below will cause 1772 * state tansition to DELAY and reset the timer, 1773 * we must set the timer now, although it is actually 1774 * meaningless. 1775 */ 1776 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1777 1778 if (ln->ln_hold) { 1779 struct mbuf *m_hold, *m_hold_next; 1780 for (m_hold = ln->ln_hold; m_hold; 1781 m_hold = m_hold_next) { 1782 struct mbuf *mpkt = NULL; 1783 1784 m_hold_next = m_hold->m_nextpkt; 1785 mpkt = m_copym(m_hold, 0, M_COPYALL, M_DONTWAIT); 1786 if (mpkt == NULL) { 1787 m_freem(m_hold); 1788 break; 1789 } 1790 mpkt->m_nextpkt = NULL; 1791 1792 /* 1793 * we assume ifp is not a p2p here, so 1794 * just set the 2nd argument as the 1795 * 1st one. 1796 */ 1797 nd6_output(ifp, ifp, mpkt, 1798 (struct sockaddr_in6 *)rt_key(rt), 1799 rt); 1800 } 1801 ln->ln_hold = NULL; 1802 } 1803 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 1804 /* probe right away */ 1805 nd6_llinfo_settimer((void *)ln, 0); 1806 } 1807 } 1808 1809 /* 1810 * ICMP6 type dependent behavior. 1811 * 1812 * NS: clear IsRouter if new entry 1813 * RS: clear IsRouter 1814 * RA: set IsRouter if there's lladdr 1815 * redir: clear IsRouter if new entry 1816 * 1817 * RA case, (1): 1818 * The spec says that we must set IsRouter in the following cases: 1819 * - If lladdr exist, set IsRouter. This means (1-5). 1820 * - If it is old entry (!newentry), set IsRouter. This means (7). 1821 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1822 * A quetion arises for (1) case. (1) case has no lladdr in the 1823 * neighbor cache, this is similar to (6). 1824 * This case is rare but we figured that we MUST NOT set IsRouter. 1825 * 1826 * newentry olladdr lladdr llchange NS RS RA redir 1827 * D R 1828 * 0 n n -- (1) c ? s 1829 * 0 y n -- (2) c s s 1830 * 0 n y -- (3) c s s 1831 * 0 y y n (4) c s s 1832 * 0 y y y (5) c s s 1833 * 1 -- n -- (6) c c c s 1834 * 1 -- y -- (7) c c s c s 1835 * 1836 * (c=clear s=set) 1837 */ 1838 switch (type & 0xff) { 1839 case ND_NEIGHBOR_SOLICIT: 1840 /* 1841 * New entry must have is_router flag cleared. 1842 */ 1843 if (is_newentry) /* (6-7) */ 1844 ln->ln_router = 0; 1845 break; 1846 case ND_REDIRECT: 1847 /* 1848 * If the icmp is a redirect to a better router, always set the 1849 * is_router flag. Otherwise, if the entry is newly created, 1850 * clear the flag. [RFC 2461, sec 8.3] 1851 */ 1852 if (code == ND_REDIRECT_ROUTER) 1853 ln->ln_router = 1; 1854 else if (is_newentry) /* (6-7) */ 1855 ln->ln_router = 0; 1856 break; 1857 case ND_ROUTER_SOLICIT: 1858 /* 1859 * is_router flag must always be cleared. 1860 */ 1861 ln->ln_router = 0; 1862 break; 1863 case ND_ROUTER_ADVERT: 1864 /* 1865 * Mark an entry with lladdr as a router. 1866 */ 1867 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */ 1868 (is_newentry && lladdr)) { /* (7) */ 1869 ln->ln_router = 1; 1870 } 1871 break; 1872 } 1873 1874 /* 1875 * When the link-layer address of a router changes, select the 1876 * best router again. In particular, when the neighbor entry is newly 1877 * created, it might affect the selection policy. 1878 * Question: can we restrict the first condition to the "is_newentry" 1879 * case? 1880 * XXX: when we hear an RA from a new router with the link-layer 1881 * address option, defrouter_select() is called twice, since 1882 * defrtrlist_update called the function as well. However, I believe 1883 * we can compromise the overhead, since it only happens the first 1884 * time. 1885 * XXX: although defrouter_select() should not have a bad effect 1886 * for those are not autoconfigured hosts, we explicitly avoid such 1887 * cases for safety. 1888 */ 1889 if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv) 1890 defrouter_select(); 1891 1892 return rt; 1893 } 1894 1895 static void 1896 nd6_slowtimo(ignored_arg) 1897 void *ignored_arg; 1898 { 1899 struct nd_ifinfo *nd6if; 1900 struct ifnet *ifp; 1901 1902 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 1903 nd6_slowtimo, NULL); 1904 IFNET_RLOCK(); 1905 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1906 nd6if = ND_IFINFO(ifp); 1907 if (nd6if->basereachable && /* already initialized */ 1908 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 1909 /* 1910 * Since reachable time rarely changes by router 1911 * advertisements, we SHOULD insure that a new random 1912 * value gets recomputed at least once every few hours. 1913 * (RFC 2461, 6.3.4) 1914 */ 1915 nd6if->recalctm = nd6_recalc_reachtm_interval; 1916 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 1917 } 1918 } 1919 IFNET_RUNLOCK(); 1920 } 1921 1922 #define senderr(e) { error = (e); goto bad;} 1923 int 1924 nd6_output(ifp, origifp, m0, dst, rt0) 1925 struct ifnet *ifp; 1926 struct ifnet *origifp; 1927 struct mbuf *m0; 1928 struct sockaddr_in6 *dst; 1929 struct rtentry *rt0; 1930 { 1931 struct mbuf *m = m0; 1932 struct rtentry *rt = rt0; 1933 struct sockaddr_in6 *gw6 = NULL; 1934 struct llinfo_nd6 *ln = NULL; 1935 int error = 0; 1936 1937 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr)) 1938 goto sendpkt; 1939 1940 if (nd6_need_cache(ifp) == 0) 1941 goto sendpkt; 1942 1943 /* 1944 * next hop determination. This routine is derived from ether_output. 1945 */ 1946 again: 1947 if (rt) { 1948 if ((rt->rt_flags & RTF_UP) == 0) { 1949 rt0 = rt = rtalloc1((struct sockaddr *)dst, 1, 0UL); 1950 if (rt != NULL) { 1951 RT_REMREF(rt); 1952 RT_UNLOCK(rt); 1953 if (rt->rt_ifp != ifp) 1954 /* 1955 * XXX maybe we should update ifp too, 1956 * but the original code didn't and I 1957 * don't know what is correct here. 1958 */ 1959 goto again; 1960 } else 1961 senderr(EHOSTUNREACH); 1962 } 1963 1964 if (rt->rt_flags & RTF_GATEWAY) { 1965 gw6 = (struct sockaddr_in6 *)rt->rt_gateway; 1966 1967 /* 1968 * We skip link-layer address resolution and NUD 1969 * if the gateway is not a neighbor from ND point 1970 * of view, regardless of the value of nd_ifinfo.flags. 1971 * The second condition is a bit tricky; we skip 1972 * if the gateway is our own address, which is 1973 * sometimes used to install a route to a p2p link. 1974 */ 1975 if (!nd6_is_addr_neighbor(gw6, ifp) || 1976 in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) { 1977 /* 1978 * We allow this kind of tricky route only 1979 * when the outgoing interface is p2p. 1980 * XXX: we may need a more generic rule here. 1981 */ 1982 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 1983 senderr(EHOSTUNREACH); 1984 1985 goto sendpkt; 1986 } 1987 1988 if (rt->rt_gwroute == 0) 1989 goto lookup; 1990 if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) { 1991 RT_LOCK(rt); 1992 rtfree(rt); rt = rt0; 1993 lookup: 1994 rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1, 0UL); 1995 if ((rt = rt->rt_gwroute) == 0) 1996 senderr(EHOSTUNREACH); 1997 RT_UNLOCK(rt); 1998 } 1999 } 2000 } 2001 2002 /* 2003 * Address resolution or Neighbor Unreachability Detection 2004 * for the next hop. 2005 * At this point, the destination of the packet must be a unicast 2006 * or an anycast address(i.e. not a multicast). 2007 */ 2008 2009 /* Look up the neighbor cache for the nexthop */ 2010 if (rt && (rt->rt_flags & RTF_LLINFO) != 0) 2011 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2012 else { 2013 /* 2014 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 2015 * the condition below is not very efficient. But we believe 2016 * it is tolerable, because this should be a rare case. 2017 */ 2018 if (nd6_is_addr_neighbor(dst, ifp) && 2019 (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL) 2020 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2021 } 2022 if (ln == NULL || rt == NULL) { 2023 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 && 2024 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { 2025 log(LOG_DEBUG, 2026 "nd6_output: can't allocate llinfo for %s " 2027 "(ln=%p, rt=%p)\n", 2028 ip6_sprintf(&dst->sin6_addr), ln, rt); 2029 senderr(EIO); /* XXX: good error? */ 2030 } 2031 2032 goto sendpkt; /* send anyway */ 2033 } 2034 2035 /* We don't have to do link-layer address resolution on a p2p link. */ 2036 if ((ifp->if_flags & IFF_POINTOPOINT) != 0 && 2037 ln->ln_state < ND6_LLINFO_REACHABLE) { 2038 ln->ln_state = ND6_LLINFO_STALE; 2039 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 2040 } 2041 2042 /* 2043 * The first time we send a packet to a neighbor whose entry is 2044 * STALE, we have to change the state to DELAY and a sets a timer to 2045 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2046 * neighbor unreachability detection on expiration. 2047 * (RFC 2461 7.3.3) 2048 */ 2049 if (ln->ln_state == ND6_LLINFO_STALE) { 2050 ln->ln_asked = 0; 2051 ln->ln_state = ND6_LLINFO_DELAY; 2052 nd6_llinfo_settimer(ln, (long)nd6_delay * hz); 2053 } 2054 2055 /* 2056 * If the neighbor cache entry has a state other than INCOMPLETE 2057 * (i.e. its link-layer address is already resolved), just 2058 * send the packet. 2059 */ 2060 if (ln->ln_state > ND6_LLINFO_INCOMPLETE) 2061 goto sendpkt; 2062 2063 /* 2064 * There is a neighbor cache entry, but no ethernet address 2065 * response yet. Append this latest packet to the end of the 2066 * packet queue in the mbuf, unless the number of the packet 2067 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, 2068 * the oldest packet in the queue will be removed. 2069 */ 2070 if (ln->ln_state == ND6_LLINFO_NOSTATE) 2071 ln->ln_state = ND6_LLINFO_INCOMPLETE; 2072 if (ln->ln_hold) { 2073 struct mbuf *m_hold; 2074 int i; 2075 2076 i = 0; 2077 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold->m_nextpkt) { 2078 i++; 2079 if (m_hold->m_nextpkt == NULL) { 2080 m_hold->m_nextpkt = m; 2081 break; 2082 } 2083 } 2084 while (i >= nd6_maxqueuelen) { 2085 m_hold = ln->ln_hold; 2086 ln->ln_hold = ln->ln_hold->m_nextpkt; 2087 m_freem(m_hold); 2088 i--; 2089 } 2090 } else { 2091 ln->ln_hold = m; 2092 } 2093 2094 /* 2095 * If there has been no NS for the neighbor after entering the 2096 * INCOMPLETE state, send the first solicitation. 2097 */ 2098 if (!ND6_LLINFO_PERMANENT(ln) && ln->ln_asked == 0) { 2099 ln->ln_asked++; 2100 nd6_llinfo_settimer(ln, 2101 (long)ND_IFINFO(ifp)->retrans * hz / 1000); 2102 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 2103 } 2104 return (0); 2105 2106 sendpkt: 2107 /* discard the packet if IPv6 operation is disabled on the interface */ 2108 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 2109 error = ENETDOWN; /* better error? */ 2110 goto bad; 2111 } 2112 2113 #ifdef IPSEC 2114 /* clean ipsec history once it goes out of the node */ 2115 ipsec_delaux(m); 2116 #endif 2117 2118 #ifdef MAC 2119 mac_create_mbuf_linklayer(ifp, m); 2120 #endif 2121 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 2122 return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst, 2123 rt)); 2124 } 2125 return ((*ifp->if_output)(ifp, m, (struct sockaddr *)dst, rt)); 2126 2127 bad: 2128 if (m) 2129 m_freem(m); 2130 return (error); 2131 } 2132 #undef senderr 2133 2134 int 2135 nd6_need_cache(ifp) 2136 struct ifnet *ifp; 2137 { 2138 /* 2139 * XXX: we currently do not make neighbor cache on any interface 2140 * other than ARCnet, Ethernet, FDDI and GIF. 2141 * 2142 * RFC2893 says: 2143 * - unidirectional tunnels needs no ND 2144 */ 2145 switch (ifp->if_type) { 2146 case IFT_ARCNET: 2147 case IFT_ETHER: 2148 case IFT_FDDI: 2149 case IFT_IEEE1394: 2150 #ifdef IFT_L2VLAN 2151 case IFT_L2VLAN: 2152 #endif 2153 #ifdef IFT_IEEE80211 2154 case IFT_IEEE80211: 2155 #endif 2156 #ifdef IFT_CARP 2157 case IFT_CARP: 2158 #endif 2159 case IFT_GIF: /* XXX need more cases? */ 2160 case IFT_PPP: 2161 case IFT_TUNNEL: 2162 case IFT_BRIDGE: 2163 return (1); 2164 default: 2165 return (0); 2166 } 2167 } 2168 2169 int 2170 nd6_storelladdr(ifp, rt0, m, dst, desten) 2171 struct ifnet *ifp; 2172 struct rtentry *rt0; 2173 struct mbuf *m; 2174 struct sockaddr *dst; 2175 u_char *desten; 2176 { 2177 struct sockaddr_dl *sdl; 2178 struct rtentry *rt; 2179 int error; 2180 2181 if (m->m_flags & M_MCAST) { 2182 int i; 2183 2184 switch (ifp->if_type) { 2185 case IFT_ETHER: 2186 case IFT_FDDI: 2187 #ifdef IFT_L2VLAN 2188 case IFT_L2VLAN: 2189 #endif 2190 #ifdef IFT_IEEE80211 2191 case IFT_IEEE80211: 2192 #endif 2193 case IFT_BRIDGE: 2194 case IFT_ISO88025: 2195 ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr, 2196 desten); 2197 return (0); 2198 case IFT_IEEE1394: 2199 /* 2200 * netbsd can use if_broadcastaddr, but we don't do so 2201 * to reduce # of ifdef. 2202 */ 2203 for (i = 0; i < ifp->if_addrlen; i++) 2204 desten[i] = ~0; 2205 return (0); 2206 case IFT_ARCNET: 2207 *desten = 0; 2208 return (0); 2209 default: 2210 m_freem(m); 2211 return (EAFNOSUPPORT); 2212 } 2213 } 2214 2215 if (rt0 == NULL) { 2216 /* this could happen, if we could not allocate memory */ 2217 m_freem(m); 2218 return (ENOMEM); 2219 } 2220 2221 error = rt_check(&rt, &rt0, dst); 2222 if (error) { 2223 m_freem(m); 2224 return (error); 2225 } 2226 RT_UNLOCK(rt); 2227 2228 if (rt->rt_gateway->sa_family != AF_LINK) { 2229 printf("nd6_storelladdr: something odd happens\n"); 2230 m_freem(m); 2231 return (EINVAL); 2232 } 2233 sdl = SDL(rt->rt_gateway); 2234 if (sdl->sdl_alen == 0) { 2235 /* this should be impossible, but we bark here for debugging */ 2236 printf("nd6_storelladdr: sdl_alen == 0\n"); 2237 m_freem(m); 2238 return (EINVAL); 2239 } 2240 2241 bcopy(LLADDR(sdl), desten, sdl->sdl_alen); 2242 return (0); 2243 } 2244 2245 static void 2246 clear_llinfo_pqueue(ln) 2247 struct llinfo_nd6 *ln; 2248 { 2249 struct mbuf *m_hold, *m_hold_next; 2250 2251 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold_next) { 2252 m_hold_next = m_hold->m_nextpkt; 2253 m_hold->m_nextpkt = NULL; 2254 m_freem(m_hold); 2255 } 2256 2257 ln->ln_hold = NULL; 2258 return; 2259 } 2260 2261 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS); 2262 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS); 2263 #ifdef SYSCTL_DECL 2264 SYSCTL_DECL(_net_inet6_icmp6); 2265 #endif 2266 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist, 2267 CTLFLAG_RD, nd6_sysctl_drlist, ""); 2268 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist, 2269 CTLFLAG_RD, nd6_sysctl_prlist, ""); 2270 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen, 2271 CTLFLAG_RW, &nd6_maxqueuelen, 1, ""); 2272 2273 static int 2274 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS) 2275 { 2276 int error; 2277 char buf[1024]; 2278 struct in6_defrouter *d, *de; 2279 struct nd_defrouter *dr; 2280 2281 if (req->newptr) 2282 return EPERM; 2283 error = 0; 2284 2285 for (dr = TAILQ_FIRST(&nd_defrouter); dr; 2286 dr = TAILQ_NEXT(dr, dr_entry)) { 2287 d = (struct in6_defrouter *)buf; 2288 de = (struct in6_defrouter *)(buf + sizeof(buf)); 2289 2290 if (d + 1 <= de) { 2291 bzero(d, sizeof(*d)); 2292 d->rtaddr.sin6_family = AF_INET6; 2293 d->rtaddr.sin6_len = sizeof(d->rtaddr); 2294 d->rtaddr.sin6_addr = dr->rtaddr; 2295 sa6_recoverscope(&d->rtaddr); 2296 d->flags = dr->flags; 2297 d->rtlifetime = dr->rtlifetime; 2298 d->expire = dr->expire; 2299 d->if_index = dr->ifp->if_index; 2300 } else 2301 panic("buffer too short"); 2302 2303 error = SYSCTL_OUT(req, buf, sizeof(*d)); 2304 if (error) 2305 break; 2306 } 2307 2308 return (error); 2309 } 2310 2311 static int 2312 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS) 2313 { 2314 int error; 2315 char buf[1024]; 2316 struct in6_prefix *p, *pe; 2317 struct nd_prefix *pr; 2318 2319 if (req->newptr) 2320 return EPERM; 2321 error = 0; 2322 2323 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 2324 u_short advrtrs; 2325 size_t advance; 2326 struct sockaddr_in6 *sin6, *s6; 2327 struct nd_pfxrouter *pfr; 2328 2329 p = (struct in6_prefix *)buf; 2330 pe = (struct in6_prefix *)(buf + sizeof(buf)); 2331 2332 if (p + 1 <= pe) { 2333 bzero(p, sizeof(*p)); 2334 sin6 = (struct sockaddr_in6 *)(p + 1); 2335 2336 p->prefix = pr->ndpr_prefix; 2337 if (sa6_recoverscope(&p->prefix)) { 2338 log(LOG_ERR, 2339 "scope error in prefix list (%s)\n", 2340 ip6_sprintf(&p->prefix.sin6_addr)); 2341 /* XXX: press on... */ 2342 } 2343 p->raflags = pr->ndpr_raf; 2344 p->prefixlen = pr->ndpr_plen; 2345 p->vltime = pr->ndpr_vltime; 2346 p->pltime = pr->ndpr_pltime; 2347 p->if_index = pr->ndpr_ifp->if_index; 2348 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2349 p->expire = 0; 2350 else { 2351 time_t maxexpire; 2352 2353 /* XXX: we assume time_t is signed. */ 2354 maxexpire = (-1) & 2355 ~((time_t)1 << 2356 ((sizeof(maxexpire) * 8) - 1)); 2357 if (pr->ndpr_vltime < 2358 maxexpire - pr->ndpr_lastupdate) { 2359 p->expire = pr->ndpr_lastupdate + 2360 pr->ndpr_vltime; 2361 } else 2362 p->expire = maxexpire; 2363 } 2364 p->refcnt = pr->ndpr_refcnt; 2365 p->flags = pr->ndpr_stateflags; 2366 p->origin = PR_ORIG_RA; 2367 advrtrs = 0; 2368 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2369 pfr = pfr->pfr_next) { 2370 if ((void *)&sin6[advrtrs + 1] > (void *)pe) { 2371 advrtrs++; 2372 continue; 2373 } 2374 s6 = &sin6[advrtrs]; 2375 bzero(s6, sizeof(*s6)); 2376 s6->sin6_family = AF_INET6; 2377 s6->sin6_len = sizeof(*sin6); 2378 s6->sin6_addr = pfr->router->rtaddr; 2379 if (sa6_recoverscope(s6)) { 2380 log(LOG_ERR, 2381 "scope error in " 2382 "prefix list (%s)\n", 2383 ip6_sprintf(&pfr->router->rtaddr)); 2384 } 2385 advrtrs++; 2386 } 2387 p->advrtrs = advrtrs; 2388 } else 2389 panic("buffer too short"); 2390 2391 advance = sizeof(*p) + sizeof(*sin6) * advrtrs; 2392 error = SYSCTL_OUT(req, buf, advance); 2393 if (error) 2394 break; 2395 } 2396 2397 return (error); 2398 } 2399