1 /* $NetBSD: nd6.c,v 1.99 2006/03/05 23:47:08 rpaulo Exp $ */ 2 /* $KAME: nd6.c,v 1.279 2002/06/08 11:16:51 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 <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: nd6.c,v 1.99 2006/03/05 23:47:08 rpaulo Exp $"); 35 36 #include "opt_ipsec.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/callout.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/ioctl.h> 50 #include <sys/syslog.h> 51 #include <sys/queue.h> 52 53 #include <net/if.h> 54 #include <net/if_dl.h> 55 #include <net/if_types.h> 56 #include <net/route.h> 57 #include <net/if_ether.h> 58 #include <net/if_fddi.h> 59 #include <net/if_arc.h> 60 61 #include <netinet/in.h> 62 #include <netinet6/in6_var.h> 63 #include <netinet/ip6.h> 64 #include <netinet6/ip6_var.h> 65 #include <netinet6/scope6_var.h> 66 #include <netinet6/nd6.h> 67 #include <netinet/icmp6.h> 68 69 #ifdef IPSEC 70 #include <netinet6/ipsec.h> 71 #endif 72 73 #include <net/net_osdep.h> 74 75 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ 76 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ 77 78 #define SIN6(s) ((struct sockaddr_in6 *)s) 79 #define SDL(s) ((struct sockaddr_dl *)s) 80 81 /* timer values */ 82 int nd6_prune = 1; /* walk list every 1 seconds */ 83 int nd6_delay = 5; /* delay first probe time 5 second */ 84 int nd6_umaxtries = 3; /* maximum unicast query */ 85 int nd6_mmaxtries = 3; /* maximum multicast query */ 86 int nd6_useloopback = 1; /* use loopback interface for local traffic */ 87 int nd6_gctimer = (60 * 60 * 24); /* 1 day: garbage collection timer */ 88 89 /* preventing too many loops in ND option parsing */ 90 int nd6_maxndopt = 10; /* max # of ND options allowed */ 91 92 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */ 93 94 int nd6_maxqueuelen = 1; /* max # of packets cached in unresolved ND entries */ 95 96 #ifdef ND6_DEBUG 97 int nd6_debug = 1; 98 #else 99 int nd6_debug = 0; 100 #endif 101 102 /* for debugging? */ 103 static int nd6_inuse, nd6_allocated; 104 105 struct llinfo_nd6 llinfo_nd6 = {&llinfo_nd6, &llinfo_nd6}; 106 struct nd_drhead nd_defrouter; 107 struct nd_prhead nd_prefix = { 0 }; 108 109 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL; 110 static struct sockaddr_in6 all1_sa; 111 112 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 *)); 117 118 struct callout nd6_slowtimo_ch = CALLOUT_INITIALIZER; 119 struct callout nd6_timer_ch = CALLOUT_INITIALIZER; 120 extern struct callout in6_tmpaddrtimer_ch; 121 122 static int fill_drlist __P((void *, size_t *, size_t)); 123 static int fill_prlist __P((void *, size_t *, size_t)); 124 125 MALLOC_DEFINE(M_IP6NDP, "NDP", "IPv6 Neighbour Discovery"); 126 127 void 128 nd6_init() 129 { 130 static int nd6_init_done = 0; 131 int i; 132 133 if (nd6_init_done) { 134 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n"); 135 return; 136 } 137 138 all1_sa.sin6_family = AF_INET6; 139 all1_sa.sin6_len = sizeof(struct sockaddr_in6); 140 for (i = 0; i < sizeof(all1_sa.sin6_addr); i++) 141 all1_sa.sin6_addr.s6_addr[i] = 0xff; 142 143 /* initialization of the default router list */ 144 TAILQ_INIT(&nd_defrouter); 145 146 nd6_init_done = 1; 147 148 /* start timer */ 149 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 150 nd6_slowtimo, NULL); 151 } 152 153 struct nd_ifinfo * 154 nd6_ifattach(ifp) 155 struct ifnet *ifp; 156 { 157 struct nd_ifinfo *nd; 158 159 nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK); 160 bzero(nd, sizeof(*nd)); 161 162 nd->initialized = 1; 163 164 nd->chlim = IPV6_DEFHLIM; 165 nd->basereachable = REACHABLE_TIME; 166 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 167 nd->retrans = RETRANS_TIMER; 168 /* 169 * Note that the default value of ip6_accept_rtadv is 0, which means 170 * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV 171 * here. 172 */ 173 nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV); 174 175 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 176 nd6_setmtu0(ifp, nd); 177 178 return nd; 179 } 180 181 void 182 nd6_ifdetach(nd) 183 struct nd_ifinfo *nd; 184 { 185 186 free(nd, M_IP6NDP); 187 } 188 189 void 190 nd6_setmtu(ifp) 191 struct ifnet *ifp; 192 { 193 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 194 } 195 196 void 197 nd6_setmtu0(ifp, ndi) 198 struct ifnet *ifp; 199 struct nd_ifinfo *ndi; 200 { 201 u_int32_t omaxmtu; 202 203 omaxmtu = ndi->maxmtu; 204 205 switch (ifp->if_type) { 206 case IFT_ARCNET: 207 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */ 208 break; 209 case IFT_FDDI: 210 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); 211 break; 212 default: 213 ndi->maxmtu = ifp->if_mtu; 214 break; 215 } 216 217 /* 218 * Decreasing the interface MTU under IPV6 minimum MTU may cause 219 * undesirable situation. We thus notify the operator of the change 220 * explicitly. The check for omaxmtu is necessary to restrict the 221 * log to the case of changing the MTU, not initializing it. 222 */ 223 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 224 log(LOG_NOTICE, "nd6_setmtu0: new link MTU on %s (%lu) is too" 225 " small for IPv6 which needs %lu\n", 226 if_name(ifp), (unsigned long)ndi->maxmtu, (unsigned long) 227 IPV6_MMTU); 228 } 229 230 if (ndi->maxmtu > in6_maxmtu) 231 in6_setmaxmtu(); /* check all interfaces just in case */ 232 } 233 234 void 235 nd6_option_init(opt, icmp6len, ndopts) 236 void *opt; 237 int icmp6len; 238 union nd_opts *ndopts; 239 { 240 241 bzero(ndopts, sizeof(*ndopts)); 242 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 243 ndopts->nd_opts_last 244 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 245 246 if (icmp6len == 0) { 247 ndopts->nd_opts_done = 1; 248 ndopts->nd_opts_search = NULL; 249 } 250 } 251 252 /* 253 * Take one ND option. 254 */ 255 struct nd_opt_hdr * 256 nd6_option(ndopts) 257 union nd_opts *ndopts; 258 { 259 struct nd_opt_hdr *nd_opt; 260 int olen; 261 262 if (ndopts == NULL) 263 panic("ndopts == NULL in nd6_option"); 264 if (ndopts->nd_opts_last == NULL) 265 panic("uninitialized ndopts in nd6_option"); 266 if (ndopts->nd_opts_search == NULL) 267 return NULL; 268 if (ndopts->nd_opts_done) 269 return NULL; 270 271 nd_opt = ndopts->nd_opts_search; 272 273 /* make sure nd_opt_len is inside the buffer */ 274 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { 275 bzero(ndopts, sizeof(*ndopts)); 276 return NULL; 277 } 278 279 olen = nd_opt->nd_opt_len << 3; 280 if (olen == 0) { 281 /* 282 * Message validation requires that all included 283 * options have a length that is greater than zero. 284 */ 285 bzero(ndopts, sizeof(*ndopts)); 286 return NULL; 287 } 288 289 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); 290 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 291 /* option overruns the end of buffer, invalid */ 292 bzero(ndopts, sizeof(*ndopts)); 293 return NULL; 294 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 295 /* reached the end of options chain */ 296 ndopts->nd_opts_done = 1; 297 ndopts->nd_opts_search = NULL; 298 } 299 return nd_opt; 300 } 301 302 /* 303 * Parse multiple ND options. 304 * This function is much easier to use, for ND routines that do not need 305 * multiple options of the same type. 306 */ 307 int 308 nd6_options(ndopts) 309 union nd_opts *ndopts; 310 { 311 struct nd_opt_hdr *nd_opt; 312 int i = 0; 313 314 if (ndopts == NULL) 315 panic("ndopts == NULL in nd6_options"); 316 if (ndopts->nd_opts_last == NULL) 317 panic("uninitialized ndopts in nd6_options"); 318 if (ndopts->nd_opts_search == NULL) 319 return 0; 320 321 while (1) { 322 nd_opt = nd6_option(ndopts); 323 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 324 /* 325 * Message validation requires that all included 326 * options have a length that is greater than zero. 327 */ 328 icmp6stat.icp6s_nd_badopt++; 329 bzero(ndopts, sizeof(*ndopts)); 330 return -1; 331 } 332 333 if (nd_opt == NULL) 334 goto skip1; 335 336 switch (nd_opt->nd_opt_type) { 337 case ND_OPT_SOURCE_LINKADDR: 338 case ND_OPT_TARGET_LINKADDR: 339 case ND_OPT_MTU: 340 case ND_OPT_REDIRECTED_HEADER: 341 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 342 nd6log((LOG_INFO, 343 "duplicated ND6 option found (type=%d)\n", 344 nd_opt->nd_opt_type)); 345 /* XXX bark? */ 346 } else { 347 ndopts->nd_opt_array[nd_opt->nd_opt_type] 348 = nd_opt; 349 } 350 break; 351 case ND_OPT_PREFIX_INFORMATION: 352 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 353 ndopts->nd_opt_array[nd_opt->nd_opt_type] 354 = nd_opt; 355 } 356 ndopts->nd_opts_pi_end = 357 (struct nd_opt_prefix_info *)nd_opt; 358 break; 359 default: 360 /* 361 * Unknown options must be silently ignored, 362 * to accomodate future extension to the protocol. 363 */ 364 nd6log((LOG_DEBUG, 365 "nd6_options: unsupported option %d - " 366 "option ignored\n", nd_opt->nd_opt_type)); 367 } 368 369 skip1: 370 i++; 371 if (i > nd6_maxndopt) { 372 icmp6stat.icp6s_nd_toomanyopt++; 373 nd6log((LOG_INFO, "too many loop in nd opt\n")); 374 break; 375 } 376 377 if (ndopts->nd_opts_done) 378 break; 379 } 380 381 return 0; 382 } 383 384 /* 385 * ND6 timer routine to handle ND6 entries 386 */ 387 void 388 nd6_llinfo_settimer(ln, xtick) 389 struct llinfo_nd6 *ln; 390 long xtick; 391 { 392 int s; 393 394 s = splsoftnet(); 395 396 if (xtick < 0) { 397 ln->ln_expire = 0; 398 ln->ln_ntick = 0; 399 callout_stop(&ln->ln_timer_ch); 400 } else { 401 ln->ln_expire = time.tv_sec + xtick / hz; 402 if (xtick > INT_MAX) { 403 ln->ln_ntick = xtick - INT_MAX; 404 callout_reset(&ln->ln_timer_ch, INT_MAX, 405 nd6_llinfo_timer, ln); 406 } else { 407 ln->ln_ntick = 0; 408 callout_reset(&ln->ln_timer_ch, xtick, 409 nd6_llinfo_timer, ln); 410 } 411 } 412 413 splx(s); 414 } 415 416 static void 417 nd6_llinfo_timer(arg) 418 void *arg; 419 { 420 int s; 421 struct llinfo_nd6 *ln; 422 struct rtentry *rt; 423 const struct sockaddr_in6 *dst; 424 struct ifnet *ifp; 425 struct nd_ifinfo *ndi = NULL; 426 427 s = splsoftnet(); 428 429 ln = (struct llinfo_nd6 *)arg; 430 431 if (ln->ln_ntick > 0) { 432 nd6_llinfo_settimer(ln, ln->ln_ntick); 433 splx(s); 434 return; 435 } 436 437 if ((rt = ln->ln_rt) == NULL) 438 panic("ln->ln_rt == NULL"); 439 if ((ifp = rt->rt_ifp) == NULL) 440 panic("ln->ln_rt->rt_ifp == NULL"); 441 ndi = ND_IFINFO(ifp); 442 dst = (struct sockaddr_in6 *)rt_key(rt); 443 444 /* sanity check */ 445 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln) 446 panic("rt_llinfo(%p) is not equal to ln(%p)", 447 rt->rt_llinfo, ln); 448 if (!dst) 449 panic("dst=0 in nd6_timer(ln=%p)", ln); 450 451 switch (ln->ln_state) { 452 case ND6_LLINFO_INCOMPLETE: 453 if (ln->ln_asked < nd6_mmaxtries) { 454 ln->ln_asked++; 455 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 456 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 457 } else { 458 struct mbuf *m = ln->ln_hold; 459 if (m) { 460 /* 461 * assuming every packet in ln_hold has 462 * the same IP header 463 */ 464 ln->ln_hold = NULL; 465 icmp6_error2(m, ICMP6_DST_UNREACH, 466 ICMP6_DST_UNREACH_ADDR, 0, rt->rt_ifp); 467 } 468 (void)nd6_free(rt, 0); 469 ln = NULL; 470 } 471 break; 472 case ND6_LLINFO_REACHABLE: 473 if (!ND6_LLINFO_PERMANENT(ln)) { 474 ln->ln_state = ND6_LLINFO_STALE; 475 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 476 } 477 break; 478 479 case ND6_LLINFO_STALE: 480 /* Garbage Collection(RFC 2461 5.3) */ 481 if (!ND6_LLINFO_PERMANENT(ln)) { 482 (void)nd6_free(rt, 1); 483 ln = NULL; 484 } 485 break; 486 487 case ND6_LLINFO_DELAY: 488 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 489 /* We need NUD */ 490 ln->ln_asked = 1; 491 ln->ln_state = ND6_LLINFO_PROBE; 492 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 493 nd6_ns_output(ifp, &dst->sin6_addr, 494 &dst->sin6_addr, ln, 0); 495 } else { 496 ln->ln_state = ND6_LLINFO_STALE; /* XXX */ 497 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 498 } 499 break; 500 case ND6_LLINFO_PROBE: 501 if (ln->ln_asked < nd6_umaxtries) { 502 ln->ln_asked++; 503 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 504 nd6_ns_output(ifp, &dst->sin6_addr, 505 &dst->sin6_addr, ln, 0); 506 } else { 507 (void)nd6_free(rt, 0); 508 ln = NULL; 509 } 510 break; 511 } 512 513 splx(s); 514 } 515 516 /* 517 * ND6 timer routine to expire default route list and prefix list 518 */ 519 void 520 nd6_timer(ignored_arg) 521 void *ignored_arg; 522 { 523 int s; 524 struct nd_defrouter *dr; 525 struct nd_prefix *pr; 526 struct in6_ifaddr *ia6, *nia6; 527 struct in6_addrlifetime *lt6; 528 529 s = splsoftnet(); 530 callout_reset(&nd6_timer_ch, nd6_prune * hz, 531 nd6_timer, NULL); 532 533 /* expire default router list */ 534 dr = TAILQ_FIRST(&nd_defrouter); 535 while (dr) { 536 if (dr->expire && dr->expire < time.tv_sec) { 537 struct nd_defrouter *t; 538 t = TAILQ_NEXT(dr, dr_entry); 539 defrtrlist_del(dr); 540 dr = t; 541 } else { 542 dr = TAILQ_NEXT(dr, dr_entry); 543 } 544 } 545 546 /* 547 * expire interface addresses. 548 * in the past the loop was inside prefix expiry processing. 549 * However, from a stricter speci-confrmance standpoint, we should 550 * rather separate address lifetimes and prefix lifetimes. 551 */ 552 addrloop: 553 for (ia6 = in6_ifaddr; ia6; ia6 = nia6) { 554 nia6 = ia6->ia_next; 555 /* check address lifetime */ 556 lt6 = &ia6->ia6_lifetime; 557 if (IFA6_IS_INVALID(ia6)) { 558 int regen = 0; 559 560 /* 561 * If the expiring address is temporary, try 562 * regenerating a new one. This would be useful when 563 * we suspended a laptop PC, then turned it on after a 564 * period that could invalidate all temporary 565 * addresses. Although we may have to restart the 566 * loop (see below), it must be after purging the 567 * address. Otherwise, we'd see an infinite loop of 568 * regeneration. 569 */ 570 if (ip6_use_tempaddr && 571 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 572 if (regen_tmpaddr(ia6) == 0) 573 regen = 1; 574 } 575 576 in6_purgeaddr(&ia6->ia_ifa); 577 578 if (regen) 579 goto addrloop; /* XXX: see below */ 580 } else if (IFA6_IS_DEPRECATED(ia6)) { 581 int oldflags = ia6->ia6_flags; 582 583 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 584 585 /* 586 * If a temporary address has just become deprecated, 587 * regenerate a new one if possible. 588 */ 589 if (ip6_use_tempaddr && 590 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 591 (oldflags & IN6_IFF_DEPRECATED) == 0) { 592 593 if (regen_tmpaddr(ia6) == 0) { 594 /* 595 * A new temporary address is 596 * generated. 597 * XXX: this means the address chain 598 * has changed while we are still in 599 * the loop. Although the change 600 * would not cause disaster (because 601 * it's not a deletion, but an 602 * addition,) we'd rather restart the 603 * loop just for safety. Or does this 604 * significantly reduce performance?? 605 */ 606 goto addrloop; 607 } 608 } 609 } else { 610 /* 611 * A new RA might have made a deprecated address 612 * preferred. 613 */ 614 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 615 } 616 } 617 618 /* expire prefix list */ 619 pr = nd_prefix.lh_first; 620 while (pr) { 621 /* 622 * check prefix lifetime. 623 * since pltime is just for autoconf, pltime processing for 624 * prefix is not necessary. 625 */ 626 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && 627 time.tv_sec - pr->ndpr_lastupdate > pr->ndpr_vltime) { 628 struct nd_prefix *t; 629 t = pr->ndpr_next; 630 631 /* 632 * address expiration and prefix expiration are 633 * separate. NEVER perform in6_purgeaddr here. 634 */ 635 636 prelist_remove(pr); 637 pr = t; 638 } else 639 pr = pr->ndpr_next; 640 } 641 splx(s); 642 } 643 644 static int 645 regen_tmpaddr(ia6) 646 struct in6_ifaddr *ia6; /* deprecated/invalidated temporary address */ 647 { 648 struct ifaddr *ifa; 649 struct ifnet *ifp; 650 struct in6_ifaddr *public_ifa6 = NULL; 651 652 ifp = ia6->ia_ifa.ifa_ifp; 653 for (ifa = ifp->if_addrlist.tqh_first; ifa; 654 ifa = ifa->ifa_list.tqe_next) { 655 struct in6_ifaddr *it6; 656 657 if (ifa->ifa_addr->sa_family != AF_INET6) 658 continue; 659 660 it6 = (struct in6_ifaddr *)ifa; 661 662 /* ignore no autoconf addresses. */ 663 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 664 continue; 665 666 /* ignore autoconf addresses with different prefixes. */ 667 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 668 continue; 669 670 /* 671 * Now we are looking at an autoconf address with the same 672 * prefix as ours. If the address is temporary and is still 673 * preferred, do not create another one. It would be rare, but 674 * could happen, for example, when we resume a laptop PC after 675 * a long period. 676 */ 677 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 678 !IFA6_IS_DEPRECATED(it6)) { 679 public_ifa6 = NULL; 680 break; 681 } 682 683 /* 684 * This is a public autoconf address that has the same prefix 685 * as ours. If it is preferred, keep it. We can't break the 686 * loop here, because there may be a still-preferred temporary 687 * address with the prefix. 688 */ 689 if (!IFA6_IS_DEPRECATED(it6)) 690 public_ifa6 = it6; 691 } 692 693 if (public_ifa6 != NULL) { 694 int e; 695 696 /* 697 * Random factor is introduced in the preferred lifetime, so 698 * we do not need additional delay (3rd arg to in6_tmpifadd). 699 */ 700 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 701 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 702 " tmp addr, errno=%d\n", e); 703 return (-1); 704 } 705 return (0); 706 } 707 708 return (-1); 709 } 710 711 /* 712 * Nuke neighbor cache/prefix/default router management table, right before 713 * ifp goes away. 714 */ 715 void 716 nd6_purge(ifp) 717 struct ifnet *ifp; 718 { 719 struct llinfo_nd6 *ln, *nln; 720 struct nd_defrouter *dr, *ndr; 721 struct nd_prefix *pr, *npr; 722 723 /* 724 * Nuke default router list entries toward ifp. 725 * We defer removal of default router list entries that is installed 726 * in the routing table, in order to keep additional side effects as 727 * small as possible. 728 */ 729 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 730 ndr = TAILQ_NEXT(dr, dr_entry); 731 if (dr->installed) 732 continue; 733 734 if (dr->ifp == ifp) 735 defrtrlist_del(dr); 736 } 737 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 738 ndr = TAILQ_NEXT(dr, dr_entry); 739 if (!dr->installed) 740 continue; 741 742 if (dr->ifp == ifp) 743 defrtrlist_del(dr); 744 } 745 746 /* Nuke prefix list entries toward ifp */ 747 for (pr = nd_prefix.lh_first; pr; pr = npr) { 748 npr = pr->ndpr_next; 749 if (pr->ndpr_ifp == ifp) { 750 /* 751 * Because if_detach() does *not* release prefixes 752 * while purging addresses the reference count will 753 * still be above zero. We therefore reset it to 754 * make sure that the prefix really gets purged. 755 */ 756 pr->ndpr_refcnt = 0; 757 /* 758 * Previously, pr->ndpr_addr is removed as well, 759 * but I strongly believe we don't have to do it. 760 * nd6_purge() is only called from in6_ifdetach(), 761 * which removes all the associated interface addresses 762 * by itself. 763 * (jinmei@kame.net 20010129) 764 */ 765 prelist_remove(pr); 766 } 767 } 768 769 /* cancel default outgoing interface setting */ 770 if (nd6_defifindex == ifp->if_index) 771 nd6_setdefaultiface(0); 772 773 if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */ 774 /* refresh default router list */ 775 defrouter_select(); 776 } 777 778 /* 779 * Nuke neighbor cache entries for the ifp. 780 * Note that rt->rt_ifp may not be the same as ifp, 781 * due to KAME goto ours hack. See RTM_RESOLVE case in 782 * nd6_rtrequest(), and ip6_input(). 783 */ 784 ln = llinfo_nd6.ln_next; 785 while (ln && ln != &llinfo_nd6) { 786 struct rtentry *rt; 787 struct sockaddr_dl *sdl; 788 789 nln = ln->ln_next; 790 rt = ln->ln_rt; 791 if (rt && rt->rt_gateway && 792 rt->rt_gateway->sa_family == AF_LINK) { 793 sdl = (struct sockaddr_dl *)rt->rt_gateway; 794 if (sdl->sdl_index == ifp->if_index) 795 nln = nd6_free(rt, 0); 796 } 797 ln = nln; 798 } 799 } 800 801 struct rtentry * 802 nd6_lookup(addr6, create, ifp) 803 struct in6_addr *addr6; 804 int create; 805 struct ifnet *ifp; 806 { 807 struct rtentry *rt; 808 struct sockaddr_in6 sin6; 809 810 bzero(&sin6, sizeof(sin6)); 811 sin6.sin6_len = sizeof(struct sockaddr_in6); 812 sin6.sin6_family = AF_INET6; 813 sin6.sin6_addr = *addr6; 814 rt = rtalloc1((struct sockaddr *)&sin6, create); 815 if (rt && (rt->rt_flags & RTF_LLINFO) == 0) { 816 /* 817 * This is the case for the default route. 818 * If we want to create a neighbor cache for the address, we 819 * should free the route for the destination and allocate an 820 * interface route. 821 */ 822 if (create) { 823 RTFREE(rt); 824 rt = NULL; 825 } 826 } 827 if (rt == NULL) { 828 if (create && ifp) { 829 int e; 830 831 /* 832 * If no route is available and create is set, 833 * we allocate a host route for the destination 834 * and treat it like an interface route. 835 * This hack is necessary for a neighbor which can't 836 * be covered by our own prefix. 837 */ 838 struct ifaddr *ifa = 839 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp); 840 if (ifa == NULL) 841 return (NULL); 842 843 /* 844 * Create a new route. RTF_LLINFO is necessary 845 * to create a Neighbor Cache entry for the 846 * destination in nd6_rtrequest which will be 847 * called in rtrequest via ifa->ifa_rtrequest. 848 */ 849 if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6, 850 ifa->ifa_addr, (struct sockaddr *)&all1_sa, 851 (ifa->ifa_flags | RTF_HOST | RTF_LLINFO) & 852 ~RTF_CLONING, &rt)) != 0) { 853 #if 0 854 log(LOG_ERR, 855 "nd6_lookup: failed to add route for a " 856 "neighbor(%s), errno=%d\n", 857 ip6_sprintf(addr6), e); 858 #endif 859 return (NULL); 860 } 861 if (rt == NULL) 862 return (NULL); 863 if (rt->rt_llinfo) { 864 struct llinfo_nd6 *ln = 865 (struct llinfo_nd6 *)rt->rt_llinfo; 866 ln->ln_state = ND6_LLINFO_NOSTATE; 867 } 868 } else 869 return (NULL); 870 } 871 rt->rt_refcnt--; 872 /* 873 * Validation for the entry. 874 * Note that the check for rt_llinfo is necessary because a cloned 875 * route from a parent route that has the L flag (e.g. the default 876 * route to a p2p interface) may have the flag, too, while the 877 * destination is not actually a neighbor. 878 * XXX: we can't use rt->rt_ifp to check for the interface, since 879 * it might be the loopback interface if the entry is for our 880 * own address on a non-loopback interface. Instead, we should 881 * use rt->rt_ifa->ifa_ifp, which would specify the REAL 882 * interface. 883 * Note also that ifa_ifp and ifp may differ when we connect two 884 * interfaces to a same link, install a link prefix to an interface, 885 * and try to install a neighbor cache on an interface that does not 886 * have a route to the prefix. 887 */ 888 if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 || 889 rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL || 890 (ifp && rt->rt_ifa->ifa_ifp != ifp)) { 891 if (create) { 892 nd6log((LOG_DEBUG, 893 "nd6_lookup: failed to lookup %s (if = %s)\n", 894 ip6_sprintf(addr6), 895 ifp ? if_name(ifp) : "unspec")); 896 } 897 return (NULL); 898 } 899 return (rt); 900 } 901 902 /* 903 * Detect if a given IPv6 address identifies a neighbor on a given link. 904 * XXX: should take care of the destination of a p2p link? 905 */ 906 int 907 nd6_is_addr_neighbor(addr, ifp) 908 struct sockaddr_in6 *addr; 909 struct ifnet *ifp; 910 { 911 struct nd_prefix *pr; 912 913 /* 914 * A link-local address is always a neighbor. 915 * XXX: a link does not necessarily specify a single interface. 916 */ 917 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 918 struct sockaddr_in6 sin6_copy; 919 u_int32_t zone; 920 921 /* 922 * We need sin6_copy since sa6_recoverscope() may modify the 923 * content (XXX). 924 */ 925 sin6_copy = *addr; 926 if (sa6_recoverscope(&sin6_copy)) 927 return (0); /* XXX: should be impossible */ 928 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 929 return (0); 930 if (sin6_copy.sin6_scope_id == zone) 931 return (1); 932 else 933 return (0); 934 } 935 936 /* 937 * If the address matches one of our on-link prefixes, it should be a 938 * neighbor. 939 */ 940 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 941 if (pr->ndpr_ifp != ifp) 942 continue; 943 944 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) 945 continue; 946 947 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 948 &addr->sin6_addr, &pr->ndpr_mask)) 949 return (1); 950 } 951 952 /* 953 * If the default router list is empty, all addresses are regarded 954 * as on-link, and thus, as a neighbor. 955 * XXX: we restrict the condition to hosts, because routers usually do 956 * not have the "default router list". 957 */ 958 if (!ip6_forwarding && TAILQ_FIRST(&nd_defrouter) == NULL && 959 nd6_defifindex == ifp->if_index) { 960 return (1); 961 } 962 963 /* 964 * Even if the address matches none of our addresses, it might be 965 * in the neighbor cache. 966 */ 967 if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL) 968 return (1); 969 970 return (0); 971 } 972 973 /* 974 * Free an nd6 llinfo entry. 975 * Since the function would cause significant changes in the kernel, DO NOT 976 * make it global, unless you have a strong reason for the change, and are sure 977 * that the change is safe. 978 */ 979 static struct llinfo_nd6 * 980 nd6_free(rt, gc) 981 struct rtentry *rt; 982 int gc; 983 { 984 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next; 985 struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 986 struct nd_defrouter *dr; 987 988 /* 989 * we used to have pfctlinput(PRC_HOSTDEAD) here. 990 * even though it is not harmful, it was not really necessary. 991 */ 992 993 /* cancel timer */ 994 nd6_llinfo_settimer(ln, -1); 995 996 if (!ip6_forwarding) { 997 int s; 998 s = splsoftnet(); 999 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr, 1000 rt->rt_ifp); 1001 1002 if (dr != NULL && dr->expire && 1003 ln->ln_state == ND6_LLINFO_STALE && gc) { 1004 /* 1005 * If the reason for the deletion is just garbage 1006 * collection, and the neighbor is an active default 1007 * router, do not delete it. Instead, reset the GC 1008 * timer using the router's lifetime. 1009 * Simply deleting the entry would affect default 1010 * router selection, which is not necessarily a good 1011 * thing, especially when we're using router preference 1012 * values. 1013 * XXX: the check for ln_state would be redundant, 1014 * but we intentionally keep it just in case. 1015 */ 1016 if (dr->expire > time.tv_sec) 1017 nd6_llinfo_settimer(ln, 1018 (dr->expire - time.tv_sec) * hz); 1019 else 1020 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1021 splx(s); 1022 return (ln->ln_next); 1023 } 1024 1025 if (ln->ln_router || dr) { 1026 /* 1027 * rt6_flush must be called whether or not the neighbor 1028 * is in the Default Router List. 1029 * See a corresponding comment in nd6_na_input(). 1030 */ 1031 rt6_flush(&in6, rt->rt_ifp); 1032 } 1033 1034 if (dr) { 1035 /* 1036 * Unreachablity of a router might affect the default 1037 * router selection and on-link detection of advertised 1038 * prefixes. 1039 */ 1040 1041 /* 1042 * Temporarily fake the state to choose a new default 1043 * router and to perform on-link determination of 1044 * prefixes correctly. 1045 * Below the state will be set correctly, 1046 * or the entry itself will be deleted. 1047 */ 1048 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1049 1050 /* 1051 * Since defrouter_select() does not affect the 1052 * on-link determination and MIP6 needs the check 1053 * before the default router selection, we perform 1054 * the check now. 1055 */ 1056 pfxlist_onlink_check(); 1057 1058 /* 1059 * refresh default router list 1060 */ 1061 defrouter_select(); 1062 } 1063 splx(s); 1064 } 1065 1066 /* 1067 * Before deleting the entry, remember the next entry as the 1068 * return value. We need this because pfxlist_onlink_check() above 1069 * might have freed other entries (particularly the old next entry) as 1070 * a side effect (XXX). 1071 */ 1072 next = ln->ln_next; 1073 1074 /* 1075 * Detach the route from the routing tree and the list of neighbor 1076 * caches, and disable the route entry not to be used in already 1077 * cached routes. 1078 */ 1079 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, 1080 rt_mask(rt), 0, (struct rtentry **)0); 1081 1082 return (next); 1083 } 1084 1085 /* 1086 * Upper-layer reachability hint for Neighbor Unreachability Detection. 1087 * 1088 * XXX cost-effective methods? 1089 */ 1090 void 1091 nd6_nud_hint(rt, dst6, force) 1092 struct rtentry *rt; 1093 struct in6_addr *dst6; 1094 int force; 1095 { 1096 struct llinfo_nd6 *ln; 1097 1098 /* 1099 * If the caller specified "rt", use that. Otherwise, resolve the 1100 * routing table by supplied "dst6". 1101 */ 1102 if (rt == NULL) { 1103 if (dst6 == NULL) 1104 return; 1105 if ((rt = nd6_lookup(dst6, 0, NULL)) == NULL) 1106 return; 1107 } 1108 1109 if ((rt->rt_flags & RTF_GATEWAY) != 0 || 1110 (rt->rt_flags & RTF_LLINFO) == 0 || 1111 !rt->rt_llinfo || !rt->rt_gateway || 1112 rt->rt_gateway->sa_family != AF_LINK) { 1113 /* This is not a host route. */ 1114 return; 1115 } 1116 1117 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1118 if (ln->ln_state < ND6_LLINFO_REACHABLE) 1119 return; 1120 1121 /* 1122 * if we get upper-layer reachability confirmation many times, 1123 * it is possible we have false information. 1124 */ 1125 if (!force) { 1126 ln->ln_byhint++; 1127 if (ln->ln_byhint > nd6_maxnudhint) 1128 return; 1129 } 1130 1131 ln->ln_state = ND6_LLINFO_REACHABLE; 1132 if (!ND6_LLINFO_PERMANENT(ln)) { 1133 nd6_llinfo_settimer(ln, 1134 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 1135 } 1136 } 1137 1138 void 1139 nd6_rtrequest(req, rt, info) 1140 int req; 1141 struct rtentry *rt; 1142 struct rt_addrinfo *info; /* xxx unused */ 1143 { 1144 struct sockaddr *gate = rt->rt_gateway; 1145 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1146 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 1147 struct ifnet *ifp = rt->rt_ifp; 1148 struct ifaddr *ifa; 1149 1150 if ((rt->rt_flags & RTF_GATEWAY) != 0) 1151 return; 1152 1153 if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) { 1154 /* 1155 * This is probably an interface direct route for a link 1156 * which does not need neighbor caches (e.g. fe80::%lo0/64). 1157 * We do not need special treatment below for such a route. 1158 * Moreover, the RTF_LLINFO flag which would be set below 1159 * would annoy the ndp(8) command. 1160 */ 1161 return; 1162 } 1163 1164 if (req == RTM_RESOLVE && 1165 (nd6_need_cache(ifp) == 0 || /* stf case */ 1166 !nd6_is_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), ifp))) { 1167 /* 1168 * FreeBSD and BSD/OS often make a cloned host route based 1169 * on a less-specific route (e.g. the default route). 1170 * If the less specific route does not have a "gateway" 1171 * (this is the case when the route just goes to a p2p or an 1172 * stf interface), we'll mistakenly make a neighbor cache for 1173 * the host route, and will see strange neighbor solicitation 1174 * for the corresponding destination. In order to avoid the 1175 * confusion, we check if the destination of the route is 1176 * a neighbor in terms of neighbor discovery, and stop the 1177 * process if not. Additionally, we remove the LLINFO flag 1178 * so that ndp(8) will not try to get the neighbor information 1179 * of the destination. 1180 */ 1181 rt->rt_flags &= ~RTF_LLINFO; 1182 return; 1183 } 1184 1185 switch (req) { 1186 case RTM_ADD: 1187 /* 1188 * There is no backward compatibility :) 1189 * 1190 * if ((rt->rt_flags & RTF_HOST) == 0 && 1191 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 1192 * rt->rt_flags |= RTF_CLONING; 1193 */ 1194 if ((rt->rt_flags & RTF_CLONING) || 1195 ((rt->rt_flags & RTF_LLINFO) && !ln)) { 1196 /* 1197 * Case 1: This route should come from a route to 1198 * interface (RTF_CLONING case) or the route should be 1199 * treated as on-link but is currently not 1200 * (RTF_LLINFO && !ln case). 1201 */ 1202 rt_setgate(rt, rt_key(rt), 1203 (struct sockaddr *)&null_sdl); 1204 gate = rt->rt_gateway; 1205 SDL(gate)->sdl_type = ifp->if_type; 1206 SDL(gate)->sdl_index = ifp->if_index; 1207 if (ln) 1208 nd6_llinfo_settimer(ln, 0); 1209 if ((rt->rt_flags & RTF_CLONING) != 0) 1210 break; 1211 } 1212 /* 1213 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here. 1214 * We don't do that here since llinfo is not ready yet. 1215 * 1216 * There are also couple of other things to be discussed: 1217 * - unsolicited NA code needs improvement beforehand 1218 * - RFC2461 says we MAY send multicast unsolicited NA 1219 * (7.2.6 paragraph 4), however, it also says that we 1220 * SHOULD provide a mechanism to prevent multicast NA storm. 1221 * we don't have anything like it right now. 1222 * note that the mechanism needs a mutual agreement 1223 * between proxies, which means that we need to implement 1224 * a new protocol, or a new kludge. 1225 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA. 1226 * we need to check ip6forwarding before sending it. 1227 * (or should we allow proxy ND configuration only for 1228 * routers? there's no mention about proxy ND from hosts) 1229 */ 1230 #if 0 1231 /* XXX it does not work */ 1232 if (rt->rt_flags & RTF_ANNOUNCE) 1233 nd6_na_output(ifp, 1234 &SIN6(rt_key(rt))->sin6_addr, 1235 &SIN6(rt_key(rt))->sin6_addr, 1236 ip6_forwarding ? ND_NA_FLAG_ROUTER : 0, 1237 1, NULL); 1238 #endif 1239 /* FALLTHROUGH */ 1240 case RTM_RESOLVE: 1241 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) { 1242 /* 1243 * Address resolution isn't necessary for a point to 1244 * point link, so we can skip this test for a p2p link. 1245 */ 1246 if (gate->sa_family != AF_LINK || 1247 gate->sa_len < sizeof(null_sdl)) { 1248 log(LOG_DEBUG, 1249 "nd6_rtrequest: bad gateway value: %s\n", 1250 if_name(ifp)); 1251 break; 1252 } 1253 SDL(gate)->sdl_type = ifp->if_type; 1254 SDL(gate)->sdl_index = ifp->if_index; 1255 } 1256 if (ln != NULL) 1257 break; /* This happens on a route change */ 1258 /* 1259 * Case 2: This route may come from cloning, or a manual route 1260 * add with a LL address. 1261 */ 1262 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln)); 1263 rt->rt_llinfo = (caddr_t)ln; 1264 if (ln == NULL) { 1265 log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n"); 1266 break; 1267 } 1268 nd6_inuse++; 1269 nd6_allocated++; 1270 bzero(ln, sizeof(*ln)); 1271 ln->ln_rt = rt; 1272 callout_init(&ln->ln_timer_ch); 1273 /* this is required for "ndp" command. - shin */ 1274 if (req == RTM_ADD) { 1275 /* 1276 * gate should have some valid AF_LINK entry, 1277 * and ln->ln_expire should have some lifetime 1278 * which is specified by ndp command. 1279 */ 1280 ln->ln_state = ND6_LLINFO_REACHABLE; 1281 ln->ln_byhint = 0; 1282 } else { 1283 /* 1284 * When req == RTM_RESOLVE, rt is created and 1285 * initialized in rtrequest(), so rt_expire is 0. 1286 */ 1287 ln->ln_state = ND6_LLINFO_NOSTATE; 1288 nd6_llinfo_settimer(ln, 0); 1289 } 1290 rt->rt_flags |= RTF_LLINFO; 1291 ln->ln_next = llinfo_nd6.ln_next; 1292 llinfo_nd6.ln_next = ln; 1293 ln->ln_prev = &llinfo_nd6; 1294 ln->ln_next->ln_prev = ln; 1295 1296 /* 1297 * check if rt_key(rt) is one of my address assigned 1298 * to the interface. 1299 */ 1300 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp, 1301 &SIN6(rt_key(rt))->sin6_addr); 1302 if (ifa) { 1303 caddr_t macp = nd6_ifptomac(ifp); 1304 nd6_llinfo_settimer(ln, -1); 1305 ln->ln_state = ND6_LLINFO_REACHABLE; 1306 ln->ln_byhint = 0; 1307 if (macp) { 1308 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen); 1309 SDL(gate)->sdl_alen = ifp->if_addrlen; 1310 } 1311 if (nd6_useloopback) { 1312 rt->rt_ifp = lo0ifp; /* XXX */ 1313 /* 1314 * Make sure rt_ifa be equal to the ifaddr 1315 * corresponding to the address. 1316 * We need this because when we refer 1317 * rt_ifa->ia6_flags in ip6_input, we assume 1318 * that the rt_ifa points to the address instead 1319 * of the loopback address. 1320 */ 1321 if (ifa != rt->rt_ifa) { 1322 IFAFREE(rt->rt_ifa); 1323 IFAREF(ifa); 1324 rt->rt_ifa = ifa; 1325 } 1326 } 1327 } else if (rt->rt_flags & RTF_ANNOUNCE) { 1328 nd6_llinfo_settimer(ln, -1); 1329 ln->ln_state = ND6_LLINFO_REACHABLE; 1330 ln->ln_byhint = 0; 1331 1332 /* join solicited node multicast for proxy ND */ 1333 if (ifp->if_flags & IFF_MULTICAST) { 1334 struct in6_addr llsol; 1335 int error; 1336 1337 llsol = SIN6(rt_key(rt))->sin6_addr; 1338 llsol.s6_addr32[0] = htonl(0xff020000); 1339 llsol.s6_addr32[1] = 0; 1340 llsol.s6_addr32[2] = htonl(1); 1341 llsol.s6_addr8[12] = 0xff; 1342 if (in6_setscope(&llsol, ifp, NULL)) 1343 break; 1344 if (!in6_addmulti(&llsol, ifp, &error, 0)) { 1345 nd6log((LOG_ERR, "%s: failed to join " 1346 "%s (errno=%d)\n", if_name(ifp), 1347 ip6_sprintf(&llsol), error)); 1348 } 1349 } 1350 } 1351 break; 1352 1353 case RTM_DELETE: 1354 if (ln == NULL) 1355 break; 1356 /* leave from solicited node multicast for proxy ND */ 1357 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 && 1358 (ifp->if_flags & IFF_MULTICAST) != 0) { 1359 struct in6_addr llsol; 1360 struct in6_multi *in6m; 1361 1362 llsol = SIN6(rt_key(rt))->sin6_addr; 1363 llsol.s6_addr32[0] = htonl(0xff020000); 1364 llsol.s6_addr32[1] = 0; 1365 llsol.s6_addr32[2] = htonl(1); 1366 llsol.s6_addr8[12] = 0xff; 1367 if (in6_setscope(&llsol, ifp, NULL) == 0) { 1368 IN6_LOOKUP_MULTI(llsol, ifp, in6m); 1369 if (in6m) 1370 in6_delmulti(in6m); 1371 } else 1372 ; /* XXX: should not happen. bark here? */ 1373 } 1374 nd6_inuse--; 1375 ln->ln_next->ln_prev = ln->ln_prev; 1376 ln->ln_prev->ln_next = ln->ln_next; 1377 ln->ln_prev = NULL; 1378 nd6_llinfo_settimer(ln, -1); 1379 rt->rt_llinfo = 0; 1380 rt->rt_flags &= ~RTF_LLINFO; 1381 if (ln->ln_hold) 1382 m_freem(ln->ln_hold); 1383 Free((caddr_t)ln); 1384 } 1385 } 1386 1387 int 1388 nd6_ioctl(cmd, data, ifp) 1389 u_long cmd; 1390 caddr_t data; 1391 struct ifnet *ifp; 1392 { 1393 struct in6_drlist *drl = (struct in6_drlist *)data; 1394 struct in6_oprlist *oprl = (struct in6_oprlist *)data; 1395 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1396 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1397 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1398 struct nd_defrouter *dr; 1399 struct nd_prefix *pr; 1400 struct rtentry *rt; 1401 int i = 0, error = 0; 1402 int s; 1403 1404 switch (cmd) { 1405 case SIOCGDRLST_IN6: 1406 /* 1407 * obsolete API, use sysctl under net.inet6.icmp6 1408 */ 1409 bzero(drl, sizeof(*drl)); 1410 s = splsoftnet(); 1411 dr = TAILQ_FIRST(&nd_defrouter); 1412 while (dr && i < DRLSTSIZ) { 1413 drl->defrouter[i].rtaddr = dr->rtaddr; 1414 in6_clearscope(&drl->defrouter[i].rtaddr); 1415 1416 drl->defrouter[i].flags = dr->flags; 1417 drl->defrouter[i].rtlifetime = dr->rtlifetime; 1418 drl->defrouter[i].expire = dr->expire; 1419 drl->defrouter[i].if_index = dr->ifp->if_index; 1420 i++; 1421 dr = TAILQ_NEXT(dr, dr_entry); 1422 } 1423 splx(s); 1424 break; 1425 case SIOCGPRLST_IN6: 1426 /* 1427 * obsolete API, use sysctl under net.inet6.icmp6 1428 * 1429 * XXX the structure in6_prlist was changed in backward- 1430 * incompatible manner. in6_oprlist is used for SIOCGPRLST_IN6, 1431 * in6_prlist is used for nd6_sysctl() - fill_prlist(). 1432 */ 1433 /* 1434 * XXX meaning of fields, especialy "raflags", is very 1435 * differnet between RA prefix list and RR/static prefix list. 1436 * how about separating ioctls into two? 1437 */ 1438 bzero(oprl, sizeof(*oprl)); 1439 s = splsoftnet(); 1440 pr = nd_prefix.lh_first; 1441 while (pr && i < PRLSTSIZ) { 1442 struct nd_pfxrouter *pfr; 1443 int j; 1444 1445 oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr; 1446 oprl->prefix[i].raflags = pr->ndpr_raf; 1447 oprl->prefix[i].prefixlen = pr->ndpr_plen; 1448 oprl->prefix[i].vltime = pr->ndpr_vltime; 1449 oprl->prefix[i].pltime = pr->ndpr_pltime; 1450 oprl->prefix[i].if_index = pr->ndpr_ifp->if_index; 1451 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1452 oprl->prefix[i].expire = 0; 1453 else { 1454 time_t maxexpire; 1455 1456 /* XXX: we assume time_t is signed. */ 1457 maxexpire = (-1) & 1458 ~((time_t)1 << 1459 ((sizeof(maxexpire) * 8) - 1)); 1460 if (pr->ndpr_vltime < 1461 maxexpire - pr->ndpr_lastupdate) { 1462 oprl->prefix[i].expire = 1463 pr->ndpr_lastupdate + 1464 pr->ndpr_vltime; 1465 } else 1466 oprl->prefix[i].expire = maxexpire; 1467 } 1468 1469 pfr = pr->ndpr_advrtrs.lh_first; 1470 j = 0; 1471 while (pfr) { 1472 if (j < DRLSTSIZ) { 1473 #define RTRADDR oprl->prefix[i].advrtr[j] 1474 RTRADDR = pfr->router->rtaddr; 1475 in6_clearscope(&RTRADDR); 1476 #undef RTRADDR 1477 } 1478 j++; 1479 pfr = pfr->pfr_next; 1480 } 1481 oprl->prefix[i].advrtrs = j; 1482 oprl->prefix[i].origin = PR_ORIG_RA; 1483 1484 i++; 1485 pr = pr->ndpr_next; 1486 } 1487 splx(s); 1488 1489 break; 1490 case OSIOCGIFINFO_IN6: 1491 #define ND ndi->ndi 1492 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1493 memset(&ND, 0, sizeof(ND)); 1494 ND.linkmtu = IN6_LINKMTU(ifp); 1495 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1496 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1497 ND.reachable = ND_IFINFO(ifp)->reachable; 1498 ND.retrans = ND_IFINFO(ifp)->retrans; 1499 ND.flags = ND_IFINFO(ifp)->flags; 1500 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1501 ND.chlim = ND_IFINFO(ifp)->chlim; 1502 break; 1503 case SIOCGIFINFO_IN6: 1504 ND = *ND_IFINFO(ifp); 1505 break; 1506 case SIOCSIFINFO_IN6: 1507 /* 1508 * used to change host variables from userland. 1509 * intented for a use on router to reflect RA configurations. 1510 */ 1511 /* 0 means 'unspecified' */ 1512 if (ND.linkmtu != 0) { 1513 if (ND.linkmtu < IPV6_MMTU || 1514 ND.linkmtu > IN6_LINKMTU(ifp)) { 1515 error = EINVAL; 1516 break; 1517 } 1518 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1519 } 1520 1521 if (ND.basereachable != 0) { 1522 int obasereachable = ND_IFINFO(ifp)->basereachable; 1523 1524 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1525 if (ND.basereachable != obasereachable) 1526 ND_IFINFO(ifp)->reachable = 1527 ND_COMPUTE_RTIME(ND.basereachable); 1528 } 1529 if (ND.retrans != 0) 1530 ND_IFINFO(ifp)->retrans = ND.retrans; 1531 if (ND.chlim != 0) 1532 ND_IFINFO(ifp)->chlim = ND.chlim; 1533 /* FALLTHROUGH */ 1534 case SIOCSIFINFO_FLAGS: 1535 ND_IFINFO(ifp)->flags = ND.flags; 1536 break; 1537 #undef ND 1538 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1539 /* sync kernel routing table with the default router list */ 1540 defrouter_reset(); 1541 defrouter_select(); 1542 break; 1543 case SIOCSPFXFLUSH_IN6: 1544 { 1545 /* flush all the prefix advertised by routers */ 1546 struct nd_prefix *pfx, *next; 1547 1548 s = splsoftnet(); 1549 for (pfx = nd_prefix.lh_first; pfx; pfx = next) { 1550 struct in6_ifaddr *ia, *ia_next; 1551 1552 next = pfx->ndpr_next; 1553 1554 if (IN6_IS_ADDR_LINKLOCAL(&pfx->ndpr_prefix.sin6_addr)) 1555 continue; /* XXX */ 1556 1557 /* do we really have to remove addresses as well? */ 1558 for (ia = in6_ifaddr; ia; ia = ia_next) { 1559 /* ia might be removed. keep the next ptr. */ 1560 ia_next = ia->ia_next; 1561 1562 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1563 continue; 1564 1565 if (ia->ia6_ndpr == pfx) 1566 in6_purgeaddr(&ia->ia_ifa); 1567 } 1568 prelist_remove(pfx); 1569 } 1570 splx(s); 1571 break; 1572 } 1573 case SIOCSRTRFLUSH_IN6: 1574 { 1575 /* flush all the default routers */ 1576 struct nd_defrouter *drtr, *next; 1577 1578 s = splsoftnet(); 1579 defrouter_reset(); 1580 for (drtr = TAILQ_FIRST(&nd_defrouter); drtr; drtr = next) { 1581 next = TAILQ_NEXT(drtr, dr_entry); 1582 defrtrlist_del(drtr); 1583 } 1584 defrouter_select(); 1585 splx(s); 1586 break; 1587 } 1588 case SIOCGNBRINFO_IN6: 1589 { 1590 struct llinfo_nd6 *ln; 1591 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1592 1593 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1594 return (error); 1595 1596 s = splsoftnet(); 1597 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL || 1598 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) { 1599 error = EINVAL; 1600 splx(s); 1601 break; 1602 } 1603 nbi->state = ln->ln_state; 1604 nbi->asked = ln->ln_asked; 1605 nbi->isrouter = ln->ln_router; 1606 nbi->expire = ln->ln_expire; 1607 splx(s); 1608 1609 break; 1610 } 1611 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1612 ndif->ifindex = nd6_defifindex; 1613 break; 1614 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1615 return (nd6_setdefaultiface(ndif->ifindex)); 1616 } 1617 return (error); 1618 } 1619 1620 /* 1621 * Create neighbor cache entry and cache link-layer address, 1622 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1623 */ 1624 struct rtentry * 1625 nd6_cache_lladdr(ifp, from, lladdr, lladdrlen, type, code) 1626 struct ifnet *ifp; 1627 struct in6_addr *from; 1628 char *lladdr; 1629 int lladdrlen; 1630 int type; /* ICMP6 type */ 1631 int code; /* type dependent information */ 1632 { 1633 struct rtentry *rt = NULL; 1634 struct llinfo_nd6 *ln = NULL; 1635 int is_newentry; 1636 struct sockaddr_dl *sdl = NULL; 1637 int do_update; 1638 int olladdr; 1639 int llchange; 1640 int newstate = 0; 1641 1642 if (ifp == NULL) 1643 panic("ifp == NULL in nd6_cache_lladdr"); 1644 if (from == NULL) 1645 panic("from == NULL in nd6_cache_lladdr"); 1646 1647 /* nothing must be updated for unspecified address */ 1648 if (IN6_IS_ADDR_UNSPECIFIED(from)) 1649 return NULL; 1650 1651 /* 1652 * Validation about ifp->if_addrlen and lladdrlen must be done in 1653 * the caller. 1654 * 1655 * XXX If the link does not have link-layer adderss, what should 1656 * we do? (ifp->if_addrlen == 0) 1657 * Spec says nothing in sections for RA, RS and NA. There's small 1658 * description on it in NS section (RFC 2461 7.2.3). 1659 */ 1660 1661 rt = nd6_lookup(from, 0, ifp); 1662 if (rt == NULL) { 1663 #if 0 1664 /* nothing must be done if there's no lladdr */ 1665 if (!lladdr || !lladdrlen) 1666 return NULL; 1667 #endif 1668 1669 rt = nd6_lookup(from, 1, ifp); 1670 is_newentry = 1; 1671 } else { 1672 /* do nothing if static ndp is set */ 1673 if (rt->rt_flags & RTF_STATIC) 1674 return NULL; 1675 is_newentry = 0; 1676 } 1677 1678 if (rt == NULL) 1679 return NULL; 1680 if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) { 1681 fail: 1682 (void)nd6_free(rt, 0); 1683 return NULL; 1684 } 1685 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1686 if (ln == NULL) 1687 goto fail; 1688 if (rt->rt_gateway == NULL) 1689 goto fail; 1690 if (rt->rt_gateway->sa_family != AF_LINK) 1691 goto fail; 1692 sdl = SDL(rt->rt_gateway); 1693 1694 olladdr = (sdl->sdl_alen) ? 1 : 0; 1695 if (olladdr && lladdr) { 1696 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 1697 llchange = 1; 1698 else 1699 llchange = 0; 1700 } else 1701 llchange = 0; 1702 1703 /* 1704 * newentry olladdr lladdr llchange (*=record) 1705 * 0 n n -- (1) 1706 * 0 y n -- (2) 1707 * 0 n y -- (3) * STALE 1708 * 0 y y n (4) * 1709 * 0 y y y (5) * STALE 1710 * 1 -- n -- (6) NOSTATE(= PASSIVE) 1711 * 1 -- y -- (7) * STALE 1712 */ 1713 1714 if (lladdr) { /* (3-5) and (7) */ 1715 /* 1716 * Record source link-layer address 1717 * XXX is it dependent to ifp->if_type? 1718 */ 1719 sdl->sdl_alen = ifp->if_addrlen; 1720 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 1721 } 1722 1723 if (!is_newentry) { 1724 if ((!olladdr && lladdr) || /* (3) */ 1725 (olladdr && lladdr && llchange)) { /* (5) */ 1726 do_update = 1; 1727 newstate = ND6_LLINFO_STALE; 1728 } else /* (1-2,4) */ 1729 do_update = 0; 1730 } else { 1731 do_update = 1; 1732 if (lladdr == NULL) /* (6) */ 1733 newstate = ND6_LLINFO_NOSTATE; 1734 else /* (7) */ 1735 newstate = ND6_LLINFO_STALE; 1736 } 1737 1738 if (do_update) { 1739 /* 1740 * Update the state of the neighbor cache. 1741 */ 1742 ln->ln_state = newstate; 1743 1744 if (ln->ln_state == ND6_LLINFO_STALE) { 1745 /* 1746 * XXX: since nd6_output() below will cause 1747 * state tansition to DELAY and reset the timer, 1748 * we must set the timer now, although it is actually 1749 * meaningless. 1750 */ 1751 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1752 1753 if (ln->ln_hold) { 1754 struct mbuf *m_hold, *m_hold_next; 1755 for (m_hold = ln->ln_hold; m_hold; 1756 m_hold = m_hold_next) { 1757 struct mbuf *mpkt = NULL; 1758 1759 m_hold_next = m_hold->m_nextpkt; 1760 mpkt = m_copym(m_hold, 0, M_COPYALL, M_DONTWAIT); 1761 if (mpkt == NULL) { 1762 m_freem(m_hold); 1763 break; 1764 } 1765 mpkt->m_nextpkt = NULL; 1766 1767 /* 1768 * we assume ifp is not a p2p here, so 1769 * just set the 2nd argument as the 1770 * 1st one. 1771 */ 1772 nd6_output(ifp, ifp, mpkt, 1773 (struct sockaddr_in6 *)rt_key(rt), 1774 rt); 1775 } 1776 ln->ln_hold = NULL; 1777 } 1778 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 1779 /* probe right away */ 1780 nd6_llinfo_settimer((void *)ln, 0); 1781 } 1782 } 1783 1784 /* 1785 * ICMP6 type dependent behavior. 1786 * 1787 * NS: clear IsRouter if new entry 1788 * RS: clear IsRouter 1789 * RA: set IsRouter if there's lladdr 1790 * redir: clear IsRouter if new entry 1791 * 1792 * RA case, (1): 1793 * The spec says that we must set IsRouter in the following cases: 1794 * - If lladdr exist, set IsRouter. This means (1-5). 1795 * - If it is old entry (!newentry), set IsRouter. This means (7). 1796 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1797 * A quetion arises for (1) case. (1) case has no lladdr in the 1798 * neighbor cache, this is similar to (6). 1799 * This case is rare but we figured that we MUST NOT set IsRouter. 1800 * 1801 * newentry olladdr lladdr llchange NS RS RA redir 1802 * D R 1803 * 0 n n -- (1) c ? s 1804 * 0 y n -- (2) c s s 1805 * 0 n y -- (3) c s s 1806 * 0 y y n (4) c s s 1807 * 0 y y y (5) c s s 1808 * 1 -- n -- (6) c c c s 1809 * 1 -- y -- (7) c c s c s 1810 * 1811 * (c=clear s=set) 1812 */ 1813 switch (type & 0xff) { 1814 case ND_NEIGHBOR_SOLICIT: 1815 /* 1816 * New entry must have is_router flag cleared. 1817 */ 1818 if (is_newentry) /* (6-7) */ 1819 ln->ln_router = 0; 1820 break; 1821 case ND_REDIRECT: 1822 /* 1823 * If the icmp is a redirect to a better router, always set the 1824 * is_router flag. Otherwise, if the entry is newly created, 1825 * clear the flag. [RFC 2461, sec 8.3] 1826 */ 1827 if (code == ND_REDIRECT_ROUTER) 1828 ln->ln_router = 1; 1829 else if (is_newentry) /* (6-7) */ 1830 ln->ln_router = 0; 1831 break; 1832 case ND_ROUTER_SOLICIT: 1833 /* 1834 * is_router flag must always be cleared. 1835 */ 1836 ln->ln_router = 0; 1837 break; 1838 case ND_ROUTER_ADVERT: 1839 /* 1840 * Mark an entry with lladdr as a router. 1841 */ 1842 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */ 1843 (is_newentry && lladdr)) { /* (7) */ 1844 ln->ln_router = 1; 1845 } 1846 break; 1847 } 1848 1849 /* 1850 * When the link-layer address of a router changes, select the 1851 * best router again. In particular, when the neighbor entry is newly 1852 * created, it might affect the selection policy. 1853 * Question: can we restrict the first condition to the "is_newentry" 1854 * case? 1855 * XXX: when we hear an RA from a new router with the link-layer 1856 * address option, defrouter_select() is called twice, since 1857 * defrtrlist_update called the function as well. However, I believe 1858 * we can compromise the overhead, since it only happens the first 1859 * time. 1860 * XXX: although defrouter_select() should not have a bad effect 1861 * for those are not autoconfigured hosts, we explicitly avoid such 1862 * cases for safety. 1863 */ 1864 if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv) 1865 defrouter_select(); 1866 1867 return rt; 1868 } 1869 1870 static void 1871 nd6_slowtimo(ignored_arg) 1872 void *ignored_arg; 1873 { 1874 int s = splsoftnet(); 1875 struct nd_ifinfo *nd6if; 1876 struct ifnet *ifp; 1877 1878 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 1879 nd6_slowtimo, NULL); 1880 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1881 { 1882 nd6if = ND_IFINFO(ifp); 1883 if (nd6if->basereachable && /* already initialized */ 1884 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 1885 /* 1886 * Since reachable time rarely changes by router 1887 * advertisements, we SHOULD insure that a new random 1888 * value gets recomputed at least once every few hours. 1889 * (RFC 2461, 6.3.4) 1890 */ 1891 nd6if->recalctm = nd6_recalc_reachtm_interval; 1892 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 1893 } 1894 } 1895 splx(s); 1896 } 1897 1898 #define senderr(e) { error = (e); goto bad;} 1899 int 1900 nd6_output(ifp, origifp, m0, dst, rt0) 1901 struct ifnet *ifp; 1902 struct ifnet *origifp; 1903 struct mbuf *m0; 1904 struct sockaddr_in6 *dst; 1905 struct rtentry *rt0; 1906 { 1907 struct mbuf *m = m0; 1908 struct rtentry *rt = rt0; 1909 struct sockaddr_in6 *gw6 = NULL; 1910 struct llinfo_nd6 *ln = NULL; 1911 int error = 0; 1912 1913 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr)) 1914 goto sendpkt; 1915 1916 if (nd6_need_cache(ifp) == 0) 1917 goto sendpkt; 1918 1919 /* 1920 * next hop determination. This routine is derived from ether_output. 1921 */ 1922 if (rt) { 1923 if ((rt->rt_flags & RTF_UP) == 0) { 1924 if ((rt0 = rt = rtalloc1((struct sockaddr *)dst, 1925 1)) != NULL) 1926 { 1927 rt->rt_refcnt--; 1928 if (rt->rt_ifp != ifp) 1929 senderr(EHOSTUNREACH); 1930 } else 1931 senderr(EHOSTUNREACH); 1932 } 1933 1934 if (rt->rt_flags & RTF_GATEWAY) { 1935 gw6 = (struct sockaddr_in6 *)rt->rt_gateway; 1936 1937 /* 1938 * We skip link-layer address resolution and NUD 1939 * if the gateway is not a neighbor from ND point 1940 * of view, regardless of the value of nd_ifinfo.flags. 1941 * The second condition is a bit tricky; we skip 1942 * if the gateway is our own address, which is 1943 * sometimes used to install a route to a p2p link. 1944 */ 1945 if (!nd6_is_addr_neighbor(gw6, ifp) || 1946 in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) { 1947 /* 1948 * We allow this kind of tricky route only 1949 * when the outgoing interface is p2p. 1950 * XXX: we may need a more generic rule here. 1951 */ 1952 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 1953 senderr(EHOSTUNREACH); 1954 1955 goto sendpkt; 1956 } 1957 1958 if (rt->rt_gwroute == 0) 1959 goto lookup; 1960 if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) { 1961 rtfree(rt); rt = rt0; 1962 lookup: 1963 rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1); 1964 if ((rt = rt->rt_gwroute) == 0) 1965 senderr(EHOSTUNREACH); 1966 /* the "G" test below also prevents rt == rt0 */ 1967 if ((rt->rt_flags & RTF_GATEWAY) || 1968 (rt->rt_ifp != ifp)) { 1969 rt->rt_refcnt--; 1970 rt0->rt_gwroute = 0; 1971 senderr(EHOSTUNREACH); 1972 } 1973 } 1974 } 1975 } 1976 1977 /* 1978 * Address resolution or Neighbor Unreachability Detection 1979 * for the next hop. 1980 * At this point, the destination of the packet must be a unicast 1981 * or an anycast address(i.e. not a multicast). 1982 */ 1983 1984 /* Look up the neighbor cache for the nexthop */ 1985 if (rt && (rt->rt_flags & RTF_LLINFO) != 0) 1986 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1987 else { 1988 /* 1989 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 1990 * the condition below is not very efficient. But we believe 1991 * it is tolerable, because this should be a rare case. 1992 */ 1993 if (nd6_is_addr_neighbor(dst, ifp) && 1994 (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL) 1995 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1996 } 1997 if (ln == NULL || rt == NULL) { 1998 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 && 1999 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { 2000 log(LOG_DEBUG, 2001 "nd6_output: can't allocate llinfo for %s " 2002 "(ln=%p, rt=%p)\n", 2003 ip6_sprintf(&dst->sin6_addr), ln, rt); 2004 senderr(EIO); /* XXX: good error? */ 2005 } 2006 2007 goto sendpkt; /* send anyway */ 2008 } 2009 2010 /* We don't have to do link-layer address resolution on a p2p link. */ 2011 if ((ifp->if_flags & IFF_POINTOPOINT) != 0 && 2012 ln->ln_state < ND6_LLINFO_REACHABLE) { 2013 ln->ln_state = ND6_LLINFO_STALE; 2014 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 2015 } 2016 2017 /* 2018 * The first time we send a packet to a neighbor whose entry is 2019 * STALE, we have to change the state to DELAY and a sets a timer to 2020 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2021 * neighbor unreachability detection on expiration. 2022 * (RFC 2461 7.3.3) 2023 */ 2024 if (ln->ln_state == ND6_LLINFO_STALE) { 2025 ln->ln_asked = 0; 2026 ln->ln_state = ND6_LLINFO_DELAY; 2027 nd6_llinfo_settimer(ln, (long)nd6_delay * hz); 2028 } 2029 2030 /* 2031 * If the neighbor cache entry has a state other than INCOMPLETE 2032 * (i.e. its link-layer address is already resolved), just 2033 * send the packet. 2034 */ 2035 if (ln->ln_state > ND6_LLINFO_INCOMPLETE) 2036 goto sendpkt; 2037 2038 /* 2039 * There is a neighbor cache entry, but no ethernet address 2040 * response yet. Append this latest packet to the end of the 2041 * packet queue in the mbuf, unless the number of the packet 2042 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, 2043 * the oldest packet in the queue will be removed. 2044 */ 2045 if (ln->ln_state == ND6_LLINFO_NOSTATE) 2046 ln->ln_state = ND6_LLINFO_INCOMPLETE; 2047 if (ln->ln_hold) { 2048 struct mbuf *m_hold; 2049 int i; 2050 2051 i = 0; 2052 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold->m_nextpkt) { 2053 i++; 2054 if (m_hold->m_nextpkt == NULL) { 2055 m_hold->m_nextpkt = m; 2056 break; 2057 } 2058 } 2059 while (i >= nd6_maxqueuelen) { 2060 m_hold = ln->ln_hold; 2061 ln->ln_hold = ln->ln_hold->m_nextpkt; 2062 m_free(m_hold); 2063 i--; 2064 } 2065 } else { 2066 ln->ln_hold = m; 2067 } 2068 2069 /* 2070 * If there has been no NS for the neighbor after entering the 2071 * INCOMPLETE state, send the first solicitation. 2072 */ 2073 if (!ND6_LLINFO_PERMANENT(ln) && ln->ln_asked == 0) { 2074 ln->ln_asked++; 2075 nd6_llinfo_settimer(ln, 2076 (long)ND_IFINFO(ifp)->retrans * hz / 1000); 2077 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 2078 } 2079 return (0); 2080 2081 sendpkt: 2082 /* discard the packet if IPv6 operation is disabled on the interface */ 2083 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 2084 error = ENETDOWN; /* better error? */ 2085 goto bad; 2086 } 2087 2088 #ifdef IPSEC 2089 /* clean ipsec history once it goes out of the node */ 2090 ipsec_delaux(m); 2091 #endif 2092 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 2093 return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst, 2094 rt)); 2095 } 2096 return ((*ifp->if_output)(ifp, m, (struct sockaddr *)dst, rt)); 2097 2098 bad: 2099 if (m) 2100 m_freem(m); 2101 return (error); 2102 } 2103 #undef senderr 2104 2105 int 2106 nd6_need_cache(ifp) 2107 struct ifnet *ifp; 2108 { 2109 /* 2110 * XXX: we currently do not make neighbor cache on any interface 2111 * other than ARCnet, Ethernet, FDDI and GIF. 2112 * 2113 * RFC2893 says: 2114 * - unidirectional tunnels needs no ND 2115 */ 2116 switch (ifp->if_type) { 2117 case IFT_ARCNET: 2118 case IFT_ETHER: 2119 case IFT_FDDI: 2120 case IFT_IEEE1394: 2121 case IFT_GIF: /* XXX need more cases? */ 2122 case IFT_PPP: 2123 case IFT_TUNNEL: 2124 return (1); 2125 default: 2126 return (0); 2127 } 2128 } 2129 2130 int 2131 nd6_storelladdr(ifp, rt, m, dst, desten) 2132 struct ifnet *ifp; 2133 struct rtentry *rt; 2134 struct mbuf *m; 2135 struct sockaddr *dst; 2136 u_char *desten; 2137 { 2138 struct sockaddr_dl *sdl; 2139 2140 if (m->m_flags & M_MCAST) { 2141 switch (ifp->if_type) { 2142 case IFT_ETHER: 2143 case IFT_FDDI: 2144 ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr, 2145 desten); 2146 return (1); 2147 case IFT_IEEE1394: 2148 bcopy(ifp->if_broadcastaddr, desten, ifp->if_addrlen); 2149 return (1); 2150 case IFT_ARCNET: 2151 *desten = 0; 2152 return (1); 2153 default: 2154 m_freem(m); 2155 return (0); 2156 } 2157 } 2158 2159 if (rt == NULL) { 2160 /* this could happen, if we could not allocate memory */ 2161 m_freem(m); 2162 return (0); 2163 } 2164 if (rt->rt_gateway->sa_family != AF_LINK) { 2165 printf("nd6_storelladdr: something odd happens\n"); 2166 m_freem(m); 2167 return (0); 2168 } 2169 sdl = SDL(rt->rt_gateway); 2170 if (sdl->sdl_alen == 0) { 2171 /* this should be impossible, but we bark here for debugging */ 2172 printf("nd6_storelladdr: sdl_alen == 0, dst=%s, if=%s\n", 2173 ip6_sprintf(&SIN6(dst)->sin6_addr), if_name(ifp)); 2174 m_freem(m); 2175 return (0); 2176 } 2177 2178 bcopy(LLADDR(sdl), desten, sdl->sdl_alen); 2179 return (1); 2180 } 2181 2182 int 2183 nd6_sysctl(name, oldp, oldlenp, newp, newlen) 2184 int name; 2185 void *oldp; /* syscall arg, need copyout */ 2186 size_t *oldlenp; 2187 void *newp; /* syscall arg, need copyin */ 2188 size_t newlen; 2189 { 2190 void *p; 2191 size_t ol; 2192 int error; 2193 2194 error = 0; 2195 2196 if (newp) 2197 return EPERM; 2198 if (oldp && !oldlenp) 2199 return EINVAL; 2200 ol = oldlenp ? *oldlenp : 0; 2201 2202 if (oldp) { 2203 p = malloc(*oldlenp, M_TEMP, M_WAITOK); 2204 if (p == NULL) 2205 return ENOMEM; 2206 } else 2207 p = NULL; 2208 switch (name) { 2209 case ICMPV6CTL_ND6_DRLIST: 2210 error = fill_drlist(p, oldlenp, ol); 2211 if (!error && p != NULL && oldp != NULL) 2212 error = copyout(p, oldp, *oldlenp); 2213 break; 2214 2215 case ICMPV6CTL_ND6_PRLIST: 2216 error = fill_prlist(p, oldlenp, ol); 2217 if (!error && p != NULL && oldp != NULL) 2218 error = copyout(p, oldp, *oldlenp); 2219 break; 2220 2221 case ICMPV6CTL_ND6_MAXQLEN: 2222 break; 2223 2224 default: 2225 error = ENOPROTOOPT; 2226 break; 2227 } 2228 if (p) 2229 free(p, M_TEMP); 2230 2231 return (error); 2232 } 2233 2234 static int 2235 fill_drlist(oldp, oldlenp, ol) 2236 void *oldp; 2237 size_t *oldlenp, ol; 2238 { 2239 int error = 0, s; 2240 struct in6_defrouter *d = NULL, *de = NULL; 2241 struct nd_defrouter *dr; 2242 size_t l; 2243 2244 s = splsoftnet(); 2245 2246 if (oldp) { 2247 d = (struct in6_defrouter *)oldp; 2248 de = (struct in6_defrouter *)((caddr_t)oldp + *oldlenp); 2249 } 2250 l = 0; 2251 2252 for (dr = TAILQ_FIRST(&nd_defrouter); dr; 2253 dr = TAILQ_NEXT(dr, dr_entry)) { 2254 2255 if (oldp && d + 1 <= de) { 2256 bzero(d, sizeof(*d)); 2257 d->rtaddr.sin6_family = AF_INET6; 2258 d->rtaddr.sin6_len = sizeof(struct sockaddr_in6); 2259 d->rtaddr.sin6_addr = dr->rtaddr; 2260 if (sa6_recoverscope(&d->rtaddr)) { 2261 log(LOG_ERR, 2262 "scope error in router list (%s)\n", 2263 ip6_sprintf(&d->rtaddr.sin6_addr)); 2264 /* XXX: press on... */ 2265 } 2266 d->flags = dr->flags; 2267 d->rtlifetime = dr->rtlifetime; 2268 d->expire = dr->expire; 2269 d->if_index = dr->ifp->if_index; 2270 } 2271 2272 l += sizeof(*d); 2273 if (d) 2274 d++; 2275 } 2276 2277 if (oldp) { 2278 *oldlenp = l; /* (caddr_t)d - (caddr_t)oldp */ 2279 if (l > ol) 2280 error = ENOMEM; 2281 } else 2282 *oldlenp = l; 2283 2284 splx(s); 2285 2286 return (error); 2287 } 2288 2289 static int 2290 fill_prlist(oldp, oldlenp, ol) 2291 void *oldp; 2292 size_t *oldlenp, ol; 2293 { 2294 int error = 0, s; 2295 struct nd_prefix *pr; 2296 struct in6_prefix *p = NULL; 2297 struct in6_prefix *pe = NULL; 2298 size_t l; 2299 2300 s = splsoftnet(); 2301 2302 if (oldp) { 2303 p = (struct in6_prefix *)oldp; 2304 pe = (struct in6_prefix *)((caddr_t)oldp + *oldlenp); 2305 } 2306 l = 0; 2307 2308 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 2309 u_short advrtrs; 2310 size_t advance; 2311 struct sockaddr_in6 *sin6; 2312 struct sockaddr_in6 *s6; 2313 struct nd_pfxrouter *pfr; 2314 2315 if (oldp && p + 1 <= pe) 2316 { 2317 bzero(p, sizeof(*p)); 2318 sin6 = (struct sockaddr_in6 *)(p + 1); 2319 2320 p->prefix = pr->ndpr_prefix; 2321 if (sa6_recoverscope(&p->prefix)) { 2322 log(LOG_ERR, 2323 "scope error in prefix list (%s)\n", 2324 ip6_sprintf(&p->prefix.sin6_addr)); 2325 /* XXX: press on... */ 2326 } 2327 p->raflags = pr->ndpr_raf; 2328 p->prefixlen = pr->ndpr_plen; 2329 p->vltime = pr->ndpr_vltime; 2330 p->pltime = pr->ndpr_pltime; 2331 p->if_index = pr->ndpr_ifp->if_index; 2332 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2333 p->expire = 0; 2334 else { 2335 time_t maxexpire; 2336 2337 /* XXX: we assume time_t is signed. */ 2338 maxexpire = (-1) & 2339 ~((time_t)1 << 2340 ((sizeof(maxexpire) * 8) - 1)); 2341 if (pr->ndpr_vltime < 2342 maxexpire - pr->ndpr_lastupdate) { 2343 p->expire = pr->ndpr_lastupdate + 2344 pr->ndpr_vltime; 2345 } else 2346 p->expire = maxexpire; 2347 } 2348 p->refcnt = pr->ndpr_refcnt; 2349 p->flags = pr->ndpr_stateflags; 2350 p->origin = PR_ORIG_RA; 2351 advrtrs = 0; 2352 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2353 pfr = pfr->pfr_next) { 2354 if ((void *)&sin6[advrtrs + 1] > (void *)pe) { 2355 advrtrs++; 2356 continue; 2357 } 2358 s6 = &sin6[advrtrs]; 2359 s6->sin6_family = AF_INET6; 2360 s6->sin6_len = sizeof(struct sockaddr_in6); 2361 s6->sin6_addr = pfr->router->rtaddr; 2362 s6->sin6_scope_id = 0; 2363 if (sa6_recoverscope(s6)) { 2364 log(LOG_ERR, 2365 "scope error in " 2366 "prefix list (%s)\n", 2367 ip6_sprintf(&pfr->router->rtaddr)); 2368 } 2369 advrtrs++; 2370 } 2371 p->advrtrs = advrtrs; 2372 } 2373 else { 2374 advrtrs = 0; 2375 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2376 pfr = pfr->pfr_next) 2377 advrtrs++; 2378 } 2379 2380 advance = sizeof(*p) + sizeof(*sin6) * advrtrs; 2381 l += advance; 2382 if (p) 2383 p = (struct in6_prefix *)((caddr_t)p + advance); 2384 } 2385 2386 if (oldp) { 2387 *oldlenp = l; /* (caddr_t)d - (caddr_t)oldp */ 2388 if (l > ol) 2389 error = ENOMEM; 2390 } else 2391 *oldlenp = l; 2392 2393 splx(s); 2394 2395 return (error); 2396 } 2397