1 /* $NetBSD: nd6.c,v 1.103 2006/06/07 22:34:04 kardel 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 1.103 2006/06/07 22:34:04 kardel 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 static void clear_llinfo_pqueue __P((struct llinfo_nd6 *)); 118 119 struct callout nd6_slowtimo_ch = CALLOUT_INITIALIZER; 120 struct callout nd6_timer_ch = CALLOUT_INITIALIZER; 121 extern struct callout in6_tmpaddrtimer_ch; 122 123 static int fill_drlist __P((void *, size_t *, size_t)); 124 static int fill_prlist __P((void *, size_t *, size_t)); 125 126 MALLOC_DEFINE(M_IP6NDP, "NDP", "IPv6 Neighbour Discovery"); 127 128 void 129 nd6_init() 130 { 131 static int nd6_init_done = 0; 132 int i; 133 134 if (nd6_init_done) { 135 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n"); 136 return; 137 } 138 139 all1_sa.sin6_family = AF_INET6; 140 all1_sa.sin6_len = sizeof(struct sockaddr_in6); 141 for (i = 0; i < sizeof(all1_sa.sin6_addr); i++) 142 all1_sa.sin6_addr.s6_addr[i] = 0xff; 143 144 /* initialization of the default router list */ 145 TAILQ_INIT(&nd_defrouter); 146 147 nd6_init_done = 1; 148 149 /* start timer */ 150 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 151 nd6_slowtimo, NULL); 152 } 153 154 struct nd_ifinfo * 155 nd6_ifattach(ifp) 156 struct ifnet *ifp; 157 { 158 struct nd_ifinfo *nd; 159 160 nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK); 161 bzero(nd, sizeof(*nd)); 162 163 nd->initialized = 1; 164 165 nd->chlim = IPV6_DEFHLIM; 166 nd->basereachable = REACHABLE_TIME; 167 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 168 nd->retrans = RETRANS_TIMER; 169 /* 170 * Note that the default value of ip6_accept_rtadv is 0, which means 171 * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV 172 * here. 173 */ 174 nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV); 175 176 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 177 nd6_setmtu0(ifp, nd); 178 179 return nd; 180 } 181 182 void 183 nd6_ifdetach(nd) 184 struct nd_ifinfo *nd; 185 { 186 187 free(nd, M_IP6NDP); 188 } 189 190 void 191 nd6_setmtu(ifp) 192 struct ifnet *ifp; 193 { 194 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 195 } 196 197 void 198 nd6_setmtu0(ifp, ndi) 199 struct ifnet *ifp; 200 struct nd_ifinfo *ndi; 201 { 202 u_int32_t omaxmtu; 203 204 omaxmtu = ndi->maxmtu; 205 206 switch (ifp->if_type) { 207 case IFT_ARCNET: 208 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */ 209 break; 210 case IFT_FDDI: 211 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); 212 break; 213 default: 214 ndi->maxmtu = ifp->if_mtu; 215 break; 216 } 217 218 /* 219 * Decreasing the interface MTU under IPV6 minimum MTU may cause 220 * undesirable situation. We thus notify the operator of the change 221 * explicitly. The check for omaxmtu is necessary to restrict the 222 * log to the case of changing the MTU, not initializing it. 223 */ 224 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 225 log(LOG_NOTICE, "nd6_setmtu0: new link MTU on %s (%lu) is too" 226 " small for IPv6 which needs %lu\n", 227 if_name(ifp), (unsigned long)ndi->maxmtu, (unsigned long) 228 IPV6_MMTU); 229 } 230 231 if (ndi->maxmtu > in6_maxmtu) 232 in6_setmaxmtu(); /* check all interfaces just in case */ 233 } 234 235 void 236 nd6_option_init(opt, icmp6len, ndopts) 237 void *opt; 238 int icmp6len; 239 union nd_opts *ndopts; 240 { 241 242 bzero(ndopts, sizeof(*ndopts)); 243 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 244 ndopts->nd_opts_last 245 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 246 247 if (icmp6len == 0) { 248 ndopts->nd_opts_done = 1; 249 ndopts->nd_opts_search = NULL; 250 } 251 } 252 253 /* 254 * Take one ND option. 255 */ 256 struct nd_opt_hdr * 257 nd6_option(ndopts) 258 union nd_opts *ndopts; 259 { 260 struct nd_opt_hdr *nd_opt; 261 int olen; 262 263 if (ndopts == NULL) 264 panic("ndopts == NULL in nd6_option"); 265 if (ndopts->nd_opts_last == NULL) 266 panic("uninitialized ndopts in nd6_option"); 267 if (ndopts->nd_opts_search == NULL) 268 return NULL; 269 if (ndopts->nd_opts_done) 270 return NULL; 271 272 nd_opt = ndopts->nd_opts_search; 273 274 /* make sure nd_opt_len is inside the buffer */ 275 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { 276 bzero(ndopts, sizeof(*ndopts)); 277 return NULL; 278 } 279 280 olen = nd_opt->nd_opt_len << 3; 281 if (olen == 0) { 282 /* 283 * Message validation requires that all included 284 * options have a length that is greater than zero. 285 */ 286 bzero(ndopts, sizeof(*ndopts)); 287 return NULL; 288 } 289 290 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); 291 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 292 /* option overruns the end of buffer, invalid */ 293 bzero(ndopts, sizeof(*ndopts)); 294 return NULL; 295 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 296 /* reached the end of options chain */ 297 ndopts->nd_opts_done = 1; 298 ndopts->nd_opts_search = NULL; 299 } 300 return nd_opt; 301 } 302 303 /* 304 * Parse multiple ND options. 305 * This function is much easier to use, for ND routines that do not need 306 * multiple options of the same type. 307 */ 308 int 309 nd6_options(ndopts) 310 union nd_opts *ndopts; 311 { 312 struct nd_opt_hdr *nd_opt; 313 int i = 0; 314 315 if (ndopts == NULL) 316 panic("ndopts == NULL in nd6_options"); 317 if (ndopts->nd_opts_last == NULL) 318 panic("uninitialized ndopts in nd6_options"); 319 if (ndopts->nd_opts_search == NULL) 320 return 0; 321 322 while (1) { 323 nd_opt = nd6_option(ndopts); 324 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 325 /* 326 * Message validation requires that all included 327 * options have a length that is greater than zero. 328 */ 329 icmp6stat.icp6s_nd_badopt++; 330 bzero(ndopts, sizeof(*ndopts)); 331 return -1; 332 } 333 334 if (nd_opt == NULL) 335 goto skip1; 336 337 switch (nd_opt->nd_opt_type) { 338 case ND_OPT_SOURCE_LINKADDR: 339 case ND_OPT_TARGET_LINKADDR: 340 case ND_OPT_MTU: 341 case ND_OPT_REDIRECTED_HEADER: 342 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 343 nd6log((LOG_INFO, 344 "duplicated ND6 option found (type=%d)\n", 345 nd_opt->nd_opt_type)); 346 /* XXX bark? */ 347 } else { 348 ndopts->nd_opt_array[nd_opt->nd_opt_type] 349 = nd_opt; 350 } 351 break; 352 case ND_OPT_PREFIX_INFORMATION: 353 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 354 ndopts->nd_opt_array[nd_opt->nd_opt_type] 355 = nd_opt; 356 } 357 ndopts->nd_opts_pi_end = 358 (struct nd_opt_prefix_info *)nd_opt; 359 break; 360 default: 361 /* 362 * Unknown options must be silently ignored, 363 * to accomodate future extension to the protocol. 364 */ 365 nd6log((LOG_DEBUG, 366 "nd6_options: unsupported option %d - " 367 "option ignored\n", nd_opt->nd_opt_type)); 368 } 369 370 skip1: 371 i++; 372 if (i > nd6_maxndopt) { 373 icmp6stat.icp6s_nd_toomanyopt++; 374 nd6log((LOG_INFO, "too many loop in nd opt\n")); 375 break; 376 } 377 378 if (ndopts->nd_opts_done) 379 break; 380 } 381 382 return 0; 383 } 384 385 /* 386 * ND6 timer routine to handle ND6 entries 387 */ 388 void 389 nd6_llinfo_settimer(ln, xtick) 390 struct llinfo_nd6 *ln; 391 long xtick; 392 { 393 int s; 394 395 s = splsoftnet(); 396 397 if (xtick < 0) { 398 ln->ln_expire = 0; 399 ln->ln_ntick = 0; 400 callout_stop(&ln->ln_timer_ch); 401 } else { 402 ln->ln_expire = time_second + xtick / hz; 403 if (xtick > INT_MAX) { 404 ln->ln_ntick = xtick - INT_MAX; 405 callout_reset(&ln->ln_timer_ch, INT_MAX, 406 nd6_llinfo_timer, ln); 407 } else { 408 ln->ln_ntick = 0; 409 callout_reset(&ln->ln_timer_ch, xtick, 410 nd6_llinfo_timer, ln); 411 } 412 } 413 414 splx(s); 415 } 416 417 static void 418 nd6_llinfo_timer(arg) 419 void *arg; 420 { 421 int s; 422 struct llinfo_nd6 *ln; 423 struct rtentry *rt; 424 const struct sockaddr_in6 *dst; 425 struct ifnet *ifp; 426 struct nd_ifinfo *ndi = NULL; 427 428 s = splsoftnet(); 429 430 ln = (struct llinfo_nd6 *)arg; 431 432 if (ln->ln_ntick > 0) { 433 nd6_llinfo_settimer(ln, ln->ln_ntick); 434 splx(s); 435 return; 436 } 437 438 if ((rt = ln->ln_rt) == NULL) 439 panic("ln->ln_rt == NULL"); 440 if ((ifp = rt->rt_ifp) == NULL) 441 panic("ln->ln_rt->rt_ifp == NULL"); 442 ndi = ND_IFINFO(ifp); 443 dst = (struct sockaddr_in6 *)rt_key(rt); 444 445 /* sanity check */ 446 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln) 447 panic("rt_llinfo(%p) is not equal to ln(%p)", 448 rt->rt_llinfo, ln); 449 if (!dst) 450 panic("dst=0 in nd6_timer(ln=%p)", ln); 451 452 switch (ln->ln_state) { 453 case ND6_LLINFO_INCOMPLETE: 454 if (ln->ln_asked < nd6_mmaxtries) { 455 ln->ln_asked++; 456 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 457 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 458 } else { 459 struct mbuf *m = ln->ln_hold; 460 if (m) { 461 struct mbuf *m0; 462 463 /* 464 * assuming every packet in ln_hold has 465 * the same IP header 466 */ 467 m0 = m->m_nextpkt; 468 m->m_nextpkt = NULL; 469 icmp6_error2(m, ICMP6_DST_UNREACH, 470 ICMP6_DST_UNREACH_ADDR, 0, rt->rt_ifp); 471 472 ln->ln_hold = m0; 473 clear_llinfo_pqueue(ln); 474 } 475 (void)nd6_free(rt, 0); 476 ln = NULL; 477 } 478 break; 479 case ND6_LLINFO_REACHABLE: 480 if (!ND6_LLINFO_PERMANENT(ln)) { 481 ln->ln_state = ND6_LLINFO_STALE; 482 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 483 } 484 break; 485 486 case ND6_LLINFO_STALE: 487 /* Garbage Collection(RFC 2461 5.3) */ 488 if (!ND6_LLINFO_PERMANENT(ln)) { 489 (void)nd6_free(rt, 1); 490 ln = NULL; 491 } 492 break; 493 494 case ND6_LLINFO_DELAY: 495 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 496 /* We need NUD */ 497 ln->ln_asked = 1; 498 ln->ln_state = ND6_LLINFO_PROBE; 499 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 500 nd6_ns_output(ifp, &dst->sin6_addr, 501 &dst->sin6_addr, ln, 0); 502 } else { 503 ln->ln_state = ND6_LLINFO_STALE; /* XXX */ 504 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 505 } 506 break; 507 case ND6_LLINFO_PROBE: 508 if (ln->ln_asked < nd6_umaxtries) { 509 ln->ln_asked++; 510 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 511 nd6_ns_output(ifp, &dst->sin6_addr, 512 &dst->sin6_addr, ln, 0); 513 } else { 514 (void)nd6_free(rt, 0); 515 ln = NULL; 516 } 517 break; 518 } 519 520 splx(s); 521 } 522 523 /* 524 * ND6 timer routine to expire default route list and prefix list 525 */ 526 void 527 nd6_timer(ignored_arg) 528 void *ignored_arg; 529 { 530 int s; 531 struct nd_defrouter *dr; 532 struct nd_prefix *pr; 533 struct in6_ifaddr *ia6, *nia6; 534 struct in6_addrlifetime *lt6; 535 536 s = splsoftnet(); 537 callout_reset(&nd6_timer_ch, nd6_prune * hz, 538 nd6_timer, NULL); 539 540 /* expire default router list */ 541 dr = TAILQ_FIRST(&nd_defrouter); 542 while (dr) { 543 if (dr->expire && dr->expire < time_second) { 544 struct nd_defrouter *t; 545 t = TAILQ_NEXT(dr, dr_entry); 546 defrtrlist_del(dr); 547 dr = t; 548 } else { 549 dr = TAILQ_NEXT(dr, dr_entry); 550 } 551 } 552 553 /* 554 * expire interface addresses. 555 * in the past the loop was inside prefix expiry processing. 556 * However, from a stricter speci-confrmance standpoint, we should 557 * rather separate address lifetimes and prefix lifetimes. 558 */ 559 addrloop: 560 for (ia6 = in6_ifaddr; ia6; ia6 = nia6) { 561 nia6 = ia6->ia_next; 562 /* check address lifetime */ 563 lt6 = &ia6->ia6_lifetime; 564 if (IFA6_IS_INVALID(ia6)) { 565 int regen = 0; 566 567 /* 568 * If the expiring address is temporary, try 569 * regenerating a new one. This would be useful when 570 * we suspended a laptop PC, then turned it on after a 571 * period that could invalidate all temporary 572 * addresses. Although we may have to restart the 573 * loop (see below), it must be after purging the 574 * address. Otherwise, we'd see an infinite loop of 575 * regeneration. 576 */ 577 if (ip6_use_tempaddr && 578 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 579 if (regen_tmpaddr(ia6) == 0) 580 regen = 1; 581 } 582 583 in6_purgeaddr(&ia6->ia_ifa); 584 585 if (regen) 586 goto addrloop; /* XXX: see below */ 587 } else if (IFA6_IS_DEPRECATED(ia6)) { 588 int oldflags = ia6->ia6_flags; 589 590 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 591 592 /* 593 * If a temporary address has just become deprecated, 594 * regenerate a new one if possible. 595 */ 596 if (ip6_use_tempaddr && 597 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 598 (oldflags & IN6_IFF_DEPRECATED) == 0) { 599 600 if (regen_tmpaddr(ia6) == 0) { 601 /* 602 * A new temporary address is 603 * generated. 604 * XXX: this means the address chain 605 * has changed while we are still in 606 * the loop. Although the change 607 * would not cause disaster (because 608 * it's not a deletion, but an 609 * addition,) we'd rather restart the 610 * loop just for safety. Or does this 611 * significantly reduce performance?? 612 */ 613 goto addrloop; 614 } 615 } 616 } else { 617 /* 618 * A new RA might have made a deprecated address 619 * preferred. 620 */ 621 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 622 } 623 } 624 625 /* expire prefix list */ 626 pr = nd_prefix.lh_first; 627 while (pr) { 628 /* 629 * check prefix lifetime. 630 * since pltime is just for autoconf, pltime processing for 631 * prefix is not necessary. 632 */ 633 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && 634 time_second - pr->ndpr_lastupdate > pr->ndpr_vltime) { 635 struct nd_prefix *t; 636 t = pr->ndpr_next; 637 638 /* 639 * address expiration and prefix expiration are 640 * separate. NEVER perform in6_purgeaddr here. 641 */ 642 643 prelist_remove(pr); 644 pr = t; 645 } else 646 pr = pr->ndpr_next; 647 } 648 splx(s); 649 } 650 651 static int 652 regen_tmpaddr(ia6) 653 struct in6_ifaddr *ia6; /* deprecated/invalidated temporary address */ 654 { 655 struct ifaddr *ifa; 656 struct ifnet *ifp; 657 struct in6_ifaddr *public_ifa6 = NULL; 658 659 ifp = ia6->ia_ifa.ifa_ifp; 660 for (ifa = ifp->if_addrlist.tqh_first; ifa; 661 ifa = ifa->ifa_list.tqe_next) { 662 struct in6_ifaddr *it6; 663 664 if (ifa->ifa_addr->sa_family != AF_INET6) 665 continue; 666 667 it6 = (struct in6_ifaddr *)ifa; 668 669 /* ignore no autoconf addresses. */ 670 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 671 continue; 672 673 /* ignore autoconf addresses with different prefixes. */ 674 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 675 continue; 676 677 /* 678 * Now we are looking at an autoconf address with the same 679 * prefix as ours. If the address is temporary and is still 680 * preferred, do not create another one. It would be rare, but 681 * could happen, for example, when we resume a laptop PC after 682 * a long period. 683 */ 684 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 685 !IFA6_IS_DEPRECATED(it6)) { 686 public_ifa6 = NULL; 687 break; 688 } 689 690 /* 691 * This is a public autoconf address that has the same prefix 692 * as ours. If it is preferred, keep it. We can't break the 693 * loop here, because there may be a still-preferred temporary 694 * address with the prefix. 695 */ 696 if (!IFA6_IS_DEPRECATED(it6)) 697 public_ifa6 = it6; 698 } 699 700 if (public_ifa6 != NULL) { 701 int e; 702 703 /* 704 * Random factor is introduced in the preferred lifetime, so 705 * we do not need additional delay (3rd arg to in6_tmpifadd). 706 */ 707 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 708 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 709 " tmp addr, errno=%d\n", e); 710 return (-1); 711 } 712 return (0); 713 } 714 715 return (-1); 716 } 717 718 /* 719 * Nuke neighbor cache/prefix/default router management table, right before 720 * ifp goes away. 721 */ 722 void 723 nd6_purge(ifp) 724 struct ifnet *ifp; 725 { 726 struct llinfo_nd6 *ln, *nln; 727 struct nd_defrouter *dr, *ndr; 728 struct nd_prefix *pr, *npr; 729 730 /* 731 * Nuke default router list entries toward ifp. 732 * We defer removal of default router list entries that is installed 733 * in the routing table, in order to keep additional side effects as 734 * small as possible. 735 */ 736 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 737 ndr = TAILQ_NEXT(dr, dr_entry); 738 if (dr->installed) 739 continue; 740 741 if (dr->ifp == ifp) 742 defrtrlist_del(dr); 743 } 744 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 745 ndr = TAILQ_NEXT(dr, dr_entry); 746 if (!dr->installed) 747 continue; 748 749 if (dr->ifp == ifp) 750 defrtrlist_del(dr); 751 } 752 753 /* Nuke prefix list entries toward ifp */ 754 for (pr = nd_prefix.lh_first; pr; pr = npr) { 755 npr = pr->ndpr_next; 756 if (pr->ndpr_ifp == ifp) { 757 /* 758 * Because if_detach() does *not* release prefixes 759 * while purging addresses the reference count will 760 * still be above zero. We therefore reset it to 761 * make sure that the prefix really gets purged. 762 */ 763 pr->ndpr_refcnt = 0; 764 /* 765 * Previously, pr->ndpr_addr is removed as well, 766 * but I strongly believe we don't have to do it. 767 * nd6_purge() is only called from in6_ifdetach(), 768 * which removes all the associated interface addresses 769 * by itself. 770 * (jinmei@kame.net 20010129) 771 */ 772 prelist_remove(pr); 773 } 774 } 775 776 /* cancel default outgoing interface setting */ 777 if (nd6_defifindex == ifp->if_index) 778 nd6_setdefaultiface(0); 779 780 if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */ 781 /* refresh default router list */ 782 defrouter_select(); 783 } 784 785 /* 786 * Nuke neighbor cache entries for the ifp. 787 * Note that rt->rt_ifp may not be the same as ifp, 788 * due to KAME goto ours hack. See RTM_RESOLVE case in 789 * nd6_rtrequest(), and ip6_input(). 790 */ 791 ln = llinfo_nd6.ln_next; 792 while (ln && ln != &llinfo_nd6) { 793 struct rtentry *rt; 794 struct sockaddr_dl *sdl; 795 796 nln = ln->ln_next; 797 rt = ln->ln_rt; 798 if (rt && rt->rt_gateway && 799 rt->rt_gateway->sa_family == AF_LINK) { 800 sdl = (struct sockaddr_dl *)rt->rt_gateway; 801 if (sdl->sdl_index == ifp->if_index) 802 nln = nd6_free(rt, 0); 803 } 804 ln = nln; 805 } 806 } 807 808 struct rtentry * 809 nd6_lookup(addr6, create, ifp) 810 struct in6_addr *addr6; 811 int create; 812 struct ifnet *ifp; 813 { 814 struct rtentry *rt; 815 struct sockaddr_in6 sin6; 816 817 bzero(&sin6, sizeof(sin6)); 818 sin6.sin6_len = sizeof(struct sockaddr_in6); 819 sin6.sin6_family = AF_INET6; 820 sin6.sin6_addr = *addr6; 821 rt = rtalloc1((struct sockaddr *)&sin6, create); 822 if (rt && (rt->rt_flags & RTF_LLINFO) == 0) { 823 /* 824 * This is the case for the default route. 825 * If we want to create a neighbor cache for the address, we 826 * should free the route for the destination and allocate an 827 * interface route. 828 */ 829 if (create) { 830 RTFREE(rt); 831 rt = NULL; 832 } 833 } 834 if (rt == NULL) { 835 if (create && ifp) { 836 int e; 837 838 /* 839 * If no route is available and create is set, 840 * we allocate a host route for the destination 841 * and treat it like an interface route. 842 * This hack is necessary for a neighbor which can't 843 * be covered by our own prefix. 844 */ 845 struct ifaddr *ifa = 846 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp); 847 if (ifa == NULL) 848 return (NULL); 849 850 /* 851 * Create a new route. RTF_LLINFO is necessary 852 * to create a Neighbor Cache entry for the 853 * destination in nd6_rtrequest which will be 854 * called in rtrequest via ifa->ifa_rtrequest. 855 */ 856 if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6, 857 ifa->ifa_addr, (struct sockaddr *)&all1_sa, 858 (ifa->ifa_flags | RTF_HOST | RTF_LLINFO) & 859 ~RTF_CLONING, &rt)) != 0) { 860 #if 0 861 log(LOG_ERR, 862 "nd6_lookup: failed to add route for a " 863 "neighbor(%s), errno=%d\n", 864 ip6_sprintf(addr6), e); 865 #endif 866 return (NULL); 867 } 868 if (rt == NULL) 869 return (NULL); 870 if (rt->rt_llinfo) { 871 struct llinfo_nd6 *ln = 872 (struct llinfo_nd6 *)rt->rt_llinfo; 873 ln->ln_state = ND6_LLINFO_NOSTATE; 874 } 875 } else 876 return (NULL); 877 } 878 rt->rt_refcnt--; 879 /* 880 * Validation for the entry. 881 * Note that the check for rt_llinfo is necessary because a cloned 882 * route from a parent route that has the L flag (e.g. the default 883 * route to a p2p interface) may have the flag, too, while the 884 * destination is not actually a neighbor. 885 * XXX: we can't use rt->rt_ifp to check for the interface, since 886 * it might be the loopback interface if the entry is for our 887 * own address on a non-loopback interface. Instead, we should 888 * use rt->rt_ifa->ifa_ifp, which would specify the REAL 889 * interface. 890 * Note also that ifa_ifp and ifp may differ when we connect two 891 * interfaces to a same link, install a link prefix to an interface, 892 * and try to install a neighbor cache on an interface that does not 893 * have a route to the prefix. 894 */ 895 if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 || 896 rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL || 897 (ifp && rt->rt_ifa->ifa_ifp != ifp)) { 898 if (create) { 899 nd6log((LOG_DEBUG, 900 "nd6_lookup: failed to lookup %s (if = %s)\n", 901 ip6_sprintf(addr6), 902 ifp ? if_name(ifp) : "unspec")); 903 } 904 return (NULL); 905 } 906 return (rt); 907 } 908 909 /* 910 * Detect if a given IPv6 address identifies a neighbor on a given link. 911 * XXX: should take care of the destination of a p2p link? 912 */ 913 int 914 nd6_is_addr_neighbor(addr, ifp) 915 struct sockaddr_in6 *addr; 916 struct ifnet *ifp; 917 { 918 struct nd_prefix *pr; 919 920 /* 921 * A link-local address is always a neighbor. 922 * XXX: a link does not necessarily specify a single interface. 923 */ 924 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 925 struct sockaddr_in6 sin6_copy; 926 u_int32_t zone; 927 928 /* 929 * We need sin6_copy since sa6_recoverscope() may modify the 930 * content (XXX). 931 */ 932 sin6_copy = *addr; 933 if (sa6_recoverscope(&sin6_copy)) 934 return (0); /* XXX: should be impossible */ 935 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 936 return (0); 937 if (sin6_copy.sin6_scope_id == zone) 938 return (1); 939 else 940 return (0); 941 } 942 943 /* 944 * If the address matches one of our on-link prefixes, it should be a 945 * neighbor. 946 */ 947 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 948 if (pr->ndpr_ifp != ifp) 949 continue; 950 951 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) 952 continue; 953 954 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 955 &addr->sin6_addr, &pr->ndpr_mask)) 956 return (1); 957 } 958 959 /* 960 * If the default router list is empty, all addresses are regarded 961 * as on-link, and thus, as a neighbor. 962 * XXX: we restrict the condition to hosts, because routers usually do 963 * not have the "default router list". 964 */ 965 if (!ip6_forwarding && TAILQ_FIRST(&nd_defrouter) == NULL && 966 nd6_defifindex == ifp->if_index) { 967 return (1); 968 } 969 970 /* 971 * Even if the address matches none of our addresses, it might be 972 * in the neighbor cache. 973 */ 974 if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL) 975 return (1); 976 977 return (0); 978 } 979 980 /* 981 * Free an nd6 llinfo entry. 982 * Since the function would cause significant changes in the kernel, DO NOT 983 * make it global, unless you have a strong reason for the change, and are sure 984 * that the change is safe. 985 */ 986 static struct llinfo_nd6 * 987 nd6_free(rt, gc) 988 struct rtentry *rt; 989 int gc; 990 { 991 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next; 992 struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 993 struct nd_defrouter *dr; 994 995 /* 996 * we used to have pfctlinput(PRC_HOSTDEAD) here. 997 * even though it is not harmful, it was not really necessary. 998 */ 999 1000 /* cancel timer */ 1001 nd6_llinfo_settimer(ln, -1); 1002 1003 if (!ip6_forwarding) { 1004 int s; 1005 s = splsoftnet(); 1006 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr, 1007 rt->rt_ifp); 1008 1009 if (dr != NULL && dr->expire && 1010 ln->ln_state == ND6_LLINFO_STALE && gc) { 1011 /* 1012 * If the reason for the deletion is just garbage 1013 * collection, and the neighbor is an active default 1014 * router, do not delete it. Instead, reset the GC 1015 * timer using the router's lifetime. 1016 * Simply deleting the entry would affect default 1017 * router selection, which is not necessarily a good 1018 * thing, especially when we're using router preference 1019 * values. 1020 * XXX: the check for ln_state would be redundant, 1021 * but we intentionally keep it just in case. 1022 */ 1023 if (dr->expire > time_second) 1024 nd6_llinfo_settimer(ln, 1025 (dr->expire - time_second) * hz); 1026 else 1027 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1028 splx(s); 1029 return (ln->ln_next); 1030 } 1031 1032 if (ln->ln_router || dr) { 1033 /* 1034 * rt6_flush must be called whether or not the neighbor 1035 * is in the Default Router List. 1036 * See a corresponding comment in nd6_na_input(). 1037 */ 1038 rt6_flush(&in6, rt->rt_ifp); 1039 } 1040 1041 if (dr) { 1042 /* 1043 * Unreachablity of a router might affect the default 1044 * router selection and on-link detection of advertised 1045 * prefixes. 1046 */ 1047 1048 /* 1049 * Temporarily fake the state to choose a new default 1050 * router and to perform on-link determination of 1051 * prefixes correctly. 1052 * Below the state will be set correctly, 1053 * or the entry itself will be deleted. 1054 */ 1055 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1056 1057 /* 1058 * Since defrouter_select() does not affect the 1059 * on-link determination and MIP6 needs the check 1060 * before the default router selection, we perform 1061 * the check now. 1062 */ 1063 pfxlist_onlink_check(); 1064 1065 /* 1066 * refresh default router list 1067 */ 1068 defrouter_select(); 1069 } 1070 splx(s); 1071 } 1072 1073 /* 1074 * Before deleting the entry, remember the next entry as the 1075 * return value. We need this because pfxlist_onlink_check() above 1076 * might have freed other entries (particularly the old next entry) as 1077 * a side effect (XXX). 1078 */ 1079 next = ln->ln_next; 1080 1081 /* 1082 * Detach the route from the routing tree and the list of neighbor 1083 * caches, and disable the route entry not to be used in already 1084 * cached routes. 1085 */ 1086 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, 1087 rt_mask(rt), 0, (struct rtentry **)0); 1088 1089 return (next); 1090 } 1091 1092 /* 1093 * Upper-layer reachability hint for Neighbor Unreachability Detection. 1094 * 1095 * XXX cost-effective methods? 1096 */ 1097 void 1098 nd6_nud_hint(rt, dst6, force) 1099 struct rtentry *rt; 1100 struct in6_addr *dst6; 1101 int force; 1102 { 1103 struct llinfo_nd6 *ln; 1104 1105 /* 1106 * If the caller specified "rt", use that. Otherwise, resolve the 1107 * routing table by supplied "dst6". 1108 */ 1109 if (rt == NULL) { 1110 if (dst6 == NULL) 1111 return; 1112 if ((rt = nd6_lookup(dst6, 0, NULL)) == NULL) 1113 return; 1114 } 1115 1116 if ((rt->rt_flags & RTF_GATEWAY) != 0 || 1117 (rt->rt_flags & RTF_LLINFO) == 0 || 1118 !rt->rt_llinfo || !rt->rt_gateway || 1119 rt->rt_gateway->sa_family != AF_LINK) { 1120 /* This is not a host route. */ 1121 return; 1122 } 1123 1124 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1125 if (ln->ln_state < ND6_LLINFO_REACHABLE) 1126 return; 1127 1128 /* 1129 * if we get upper-layer reachability confirmation many times, 1130 * it is possible we have false information. 1131 */ 1132 if (!force) { 1133 ln->ln_byhint++; 1134 if (ln->ln_byhint > nd6_maxnudhint) 1135 return; 1136 } 1137 1138 ln->ln_state = ND6_LLINFO_REACHABLE; 1139 if (!ND6_LLINFO_PERMANENT(ln)) { 1140 nd6_llinfo_settimer(ln, 1141 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 1142 } 1143 } 1144 1145 void 1146 nd6_rtrequest(req, rt, info) 1147 int req; 1148 struct rtentry *rt; 1149 struct rt_addrinfo *info; /* xxx unused */ 1150 { 1151 struct sockaddr *gate = rt->rt_gateway; 1152 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1153 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 1154 struct ifnet *ifp = rt->rt_ifp; 1155 struct ifaddr *ifa; 1156 1157 if ((rt->rt_flags & RTF_GATEWAY) != 0) 1158 return; 1159 1160 if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) { 1161 /* 1162 * This is probably an interface direct route for a link 1163 * which does not need neighbor caches (e.g. fe80::%lo0/64). 1164 * We do not need special treatment below for such a route. 1165 * Moreover, the RTF_LLINFO flag which would be set below 1166 * would annoy the ndp(8) command. 1167 */ 1168 return; 1169 } 1170 1171 if (req == RTM_RESOLVE && 1172 (nd6_need_cache(ifp) == 0 || /* stf case */ 1173 !nd6_is_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), ifp))) { 1174 /* 1175 * FreeBSD and BSD/OS often make a cloned host route based 1176 * on a less-specific route (e.g. the default route). 1177 * If the less specific route does not have a "gateway" 1178 * (this is the case when the route just goes to a p2p or an 1179 * stf interface), we'll mistakenly make a neighbor cache for 1180 * the host route, and will see strange neighbor solicitation 1181 * for the corresponding destination. In order to avoid the 1182 * confusion, we check if the destination of the route is 1183 * a neighbor in terms of neighbor discovery, and stop the 1184 * process if not. Additionally, we remove the LLINFO flag 1185 * so that ndp(8) will not try to get the neighbor information 1186 * of the destination. 1187 */ 1188 rt->rt_flags &= ~RTF_LLINFO; 1189 return; 1190 } 1191 1192 switch (req) { 1193 case RTM_ADD: 1194 /* 1195 * There is no backward compatibility :) 1196 * 1197 * if ((rt->rt_flags & RTF_HOST) == 0 && 1198 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 1199 * rt->rt_flags |= RTF_CLONING; 1200 */ 1201 if ((rt->rt_flags & RTF_CLONING) || 1202 ((rt->rt_flags & RTF_LLINFO) && !ln)) { 1203 /* 1204 * Case 1: This route should come from a route to 1205 * interface (RTF_CLONING case) or the route should be 1206 * treated as on-link but is currently not 1207 * (RTF_LLINFO && !ln case). 1208 */ 1209 rt_setgate(rt, rt_key(rt), 1210 (struct sockaddr *)&null_sdl); 1211 gate = rt->rt_gateway; 1212 SDL(gate)->sdl_type = ifp->if_type; 1213 SDL(gate)->sdl_index = ifp->if_index; 1214 if (ln) 1215 nd6_llinfo_settimer(ln, 0); 1216 if ((rt->rt_flags & RTF_CLONING) != 0) 1217 break; 1218 } 1219 /* 1220 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here. 1221 * We don't do that here since llinfo is not ready yet. 1222 * 1223 * There are also couple of other things to be discussed: 1224 * - unsolicited NA code needs improvement beforehand 1225 * - RFC2461 says we MAY send multicast unsolicited NA 1226 * (7.2.6 paragraph 4), however, it also says that we 1227 * SHOULD provide a mechanism to prevent multicast NA storm. 1228 * we don't have anything like it right now. 1229 * note that the mechanism needs a mutual agreement 1230 * between proxies, which means that we need to implement 1231 * a new protocol, or a new kludge. 1232 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA. 1233 * we need to check ip6forwarding before sending it. 1234 * (or should we allow proxy ND configuration only for 1235 * routers? there's no mention about proxy ND from hosts) 1236 */ 1237 #if 0 1238 /* XXX it does not work */ 1239 if (rt->rt_flags & RTF_ANNOUNCE) 1240 nd6_na_output(ifp, 1241 &SIN6(rt_key(rt))->sin6_addr, 1242 &SIN6(rt_key(rt))->sin6_addr, 1243 ip6_forwarding ? ND_NA_FLAG_ROUTER : 0, 1244 1, NULL); 1245 #endif 1246 /* FALLTHROUGH */ 1247 case RTM_RESOLVE: 1248 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) { 1249 /* 1250 * Address resolution isn't necessary for a point to 1251 * point link, so we can skip this test for a p2p link. 1252 */ 1253 if (gate->sa_family != AF_LINK || 1254 gate->sa_len < sizeof(null_sdl)) { 1255 log(LOG_DEBUG, 1256 "nd6_rtrequest: bad gateway value: %s\n", 1257 if_name(ifp)); 1258 break; 1259 } 1260 SDL(gate)->sdl_type = ifp->if_type; 1261 SDL(gate)->sdl_index = ifp->if_index; 1262 } 1263 if (ln != NULL) 1264 break; /* This happens on a route change */ 1265 /* 1266 * Case 2: This route may come from cloning, or a manual route 1267 * add with a LL address. 1268 */ 1269 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln)); 1270 rt->rt_llinfo = (caddr_t)ln; 1271 if (ln == NULL) { 1272 log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n"); 1273 break; 1274 } 1275 nd6_inuse++; 1276 nd6_allocated++; 1277 bzero(ln, sizeof(*ln)); 1278 ln->ln_rt = rt; 1279 callout_init(&ln->ln_timer_ch); 1280 /* this is required for "ndp" command. - shin */ 1281 if (req == RTM_ADD) { 1282 /* 1283 * gate should have some valid AF_LINK entry, 1284 * and ln->ln_expire should have some lifetime 1285 * which is specified by ndp command. 1286 */ 1287 ln->ln_state = ND6_LLINFO_REACHABLE; 1288 ln->ln_byhint = 0; 1289 } else { 1290 /* 1291 * When req == RTM_RESOLVE, rt is created and 1292 * initialized in rtrequest(), so rt_expire is 0. 1293 */ 1294 ln->ln_state = ND6_LLINFO_NOSTATE; 1295 nd6_llinfo_settimer(ln, 0); 1296 } 1297 rt->rt_flags |= RTF_LLINFO; 1298 ln->ln_next = llinfo_nd6.ln_next; 1299 llinfo_nd6.ln_next = ln; 1300 ln->ln_prev = &llinfo_nd6; 1301 ln->ln_next->ln_prev = ln; 1302 1303 /* 1304 * check if rt_key(rt) is one of my address assigned 1305 * to the interface. 1306 */ 1307 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp, 1308 &SIN6(rt_key(rt))->sin6_addr); 1309 if (ifa) { 1310 caddr_t macp = nd6_ifptomac(ifp); 1311 nd6_llinfo_settimer(ln, -1); 1312 ln->ln_state = ND6_LLINFO_REACHABLE; 1313 ln->ln_byhint = 0; 1314 if (macp) { 1315 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen); 1316 SDL(gate)->sdl_alen = ifp->if_addrlen; 1317 } 1318 if (nd6_useloopback) { 1319 rt->rt_ifp = lo0ifp; /* XXX */ 1320 /* 1321 * Make sure rt_ifa be equal to the ifaddr 1322 * corresponding to the address. 1323 * We need this because when we refer 1324 * rt_ifa->ia6_flags in ip6_input, we assume 1325 * that the rt_ifa points to the address instead 1326 * of the loopback address. 1327 */ 1328 if (ifa != rt->rt_ifa) { 1329 IFAFREE(rt->rt_ifa); 1330 IFAREF(ifa); 1331 rt->rt_ifa = ifa; 1332 } 1333 } 1334 } else if (rt->rt_flags & RTF_ANNOUNCE) { 1335 nd6_llinfo_settimer(ln, -1); 1336 ln->ln_state = ND6_LLINFO_REACHABLE; 1337 ln->ln_byhint = 0; 1338 1339 /* join solicited node multicast for proxy ND */ 1340 if (ifp->if_flags & IFF_MULTICAST) { 1341 struct in6_addr llsol; 1342 int error; 1343 1344 llsol = SIN6(rt_key(rt))->sin6_addr; 1345 llsol.s6_addr32[0] = htonl(0xff020000); 1346 llsol.s6_addr32[1] = 0; 1347 llsol.s6_addr32[2] = htonl(1); 1348 llsol.s6_addr8[12] = 0xff; 1349 if (in6_setscope(&llsol, ifp, NULL)) 1350 break; 1351 if (!in6_addmulti(&llsol, ifp, &error, 0)) { 1352 nd6log((LOG_ERR, "%s: failed to join " 1353 "%s (errno=%d)\n", if_name(ifp), 1354 ip6_sprintf(&llsol), error)); 1355 } 1356 } 1357 } 1358 break; 1359 1360 case RTM_DELETE: 1361 if (ln == NULL) 1362 break; 1363 /* leave from solicited node multicast for proxy ND */ 1364 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 && 1365 (ifp->if_flags & IFF_MULTICAST) != 0) { 1366 struct in6_addr llsol; 1367 struct in6_multi *in6m; 1368 1369 llsol = SIN6(rt_key(rt))->sin6_addr; 1370 llsol.s6_addr32[0] = htonl(0xff020000); 1371 llsol.s6_addr32[1] = 0; 1372 llsol.s6_addr32[2] = htonl(1); 1373 llsol.s6_addr8[12] = 0xff; 1374 if (in6_setscope(&llsol, ifp, NULL) == 0) { 1375 IN6_LOOKUP_MULTI(llsol, ifp, in6m); 1376 if (in6m) 1377 in6_delmulti(in6m); 1378 } else 1379 ; /* XXX: should not happen. bark here? */ 1380 } 1381 nd6_inuse--; 1382 ln->ln_next->ln_prev = ln->ln_prev; 1383 ln->ln_prev->ln_next = ln->ln_next; 1384 ln->ln_prev = NULL; 1385 nd6_llinfo_settimer(ln, -1); 1386 rt->rt_llinfo = 0; 1387 rt->rt_flags &= ~RTF_LLINFO; 1388 clear_llinfo_pqueue(ln); 1389 Free((caddr_t)ln); 1390 } 1391 } 1392 1393 int 1394 nd6_ioctl(cmd, data, ifp) 1395 u_long cmd; 1396 caddr_t data; 1397 struct ifnet *ifp; 1398 { 1399 struct in6_drlist *drl = (struct in6_drlist *)data; 1400 struct in6_oprlist *oprl = (struct in6_oprlist *)data; 1401 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1402 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1403 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1404 struct nd_defrouter *dr; 1405 struct nd_prefix *pr; 1406 struct rtentry *rt; 1407 int i = 0, error = 0; 1408 int s; 1409 1410 switch (cmd) { 1411 case SIOCGDRLST_IN6: 1412 /* 1413 * obsolete API, use sysctl under net.inet6.icmp6 1414 */ 1415 bzero(drl, sizeof(*drl)); 1416 s = splsoftnet(); 1417 dr = TAILQ_FIRST(&nd_defrouter); 1418 while (dr && i < DRLSTSIZ) { 1419 drl->defrouter[i].rtaddr = dr->rtaddr; 1420 in6_clearscope(&drl->defrouter[i].rtaddr); 1421 1422 drl->defrouter[i].flags = dr->flags; 1423 drl->defrouter[i].rtlifetime = dr->rtlifetime; 1424 drl->defrouter[i].expire = dr->expire; 1425 drl->defrouter[i].if_index = dr->ifp->if_index; 1426 i++; 1427 dr = TAILQ_NEXT(dr, dr_entry); 1428 } 1429 splx(s); 1430 break; 1431 case SIOCGPRLST_IN6: 1432 /* 1433 * obsolete API, use sysctl under net.inet6.icmp6 1434 * 1435 * XXX the structure in6_prlist was changed in backward- 1436 * incompatible manner. in6_oprlist is used for SIOCGPRLST_IN6, 1437 * in6_prlist is used for nd6_sysctl() - fill_prlist(). 1438 */ 1439 /* 1440 * XXX meaning of fields, especialy "raflags", is very 1441 * differnet between RA prefix list and RR/static prefix list. 1442 * how about separating ioctls into two? 1443 */ 1444 bzero(oprl, sizeof(*oprl)); 1445 s = splsoftnet(); 1446 pr = nd_prefix.lh_first; 1447 while (pr && i < PRLSTSIZ) { 1448 struct nd_pfxrouter *pfr; 1449 int j; 1450 1451 oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr; 1452 oprl->prefix[i].raflags = pr->ndpr_raf; 1453 oprl->prefix[i].prefixlen = pr->ndpr_plen; 1454 oprl->prefix[i].vltime = pr->ndpr_vltime; 1455 oprl->prefix[i].pltime = pr->ndpr_pltime; 1456 oprl->prefix[i].if_index = pr->ndpr_ifp->if_index; 1457 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1458 oprl->prefix[i].expire = 0; 1459 else { 1460 time_t maxexpire; 1461 1462 /* XXX: we assume time_t is signed. */ 1463 maxexpire = (-1) & 1464 ~((time_t)1 << 1465 ((sizeof(maxexpire) * 8) - 1)); 1466 if (pr->ndpr_vltime < 1467 maxexpire - pr->ndpr_lastupdate) { 1468 oprl->prefix[i].expire = 1469 pr->ndpr_lastupdate + 1470 pr->ndpr_vltime; 1471 } else 1472 oprl->prefix[i].expire = maxexpire; 1473 } 1474 1475 pfr = pr->ndpr_advrtrs.lh_first; 1476 j = 0; 1477 while (pfr) { 1478 if (j < DRLSTSIZ) { 1479 #define RTRADDR oprl->prefix[i].advrtr[j] 1480 RTRADDR = pfr->router->rtaddr; 1481 in6_clearscope(&RTRADDR); 1482 #undef RTRADDR 1483 } 1484 j++; 1485 pfr = pfr->pfr_next; 1486 } 1487 oprl->prefix[i].advrtrs = j; 1488 oprl->prefix[i].origin = PR_ORIG_RA; 1489 1490 i++; 1491 pr = pr->ndpr_next; 1492 } 1493 splx(s); 1494 1495 break; 1496 case OSIOCGIFINFO_IN6: 1497 #define ND ndi->ndi 1498 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1499 memset(&ND, 0, sizeof(ND)); 1500 ND.linkmtu = IN6_LINKMTU(ifp); 1501 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1502 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1503 ND.reachable = ND_IFINFO(ifp)->reachable; 1504 ND.retrans = ND_IFINFO(ifp)->retrans; 1505 ND.flags = ND_IFINFO(ifp)->flags; 1506 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1507 ND.chlim = ND_IFINFO(ifp)->chlim; 1508 break; 1509 case SIOCGIFINFO_IN6: 1510 ND = *ND_IFINFO(ifp); 1511 break; 1512 case SIOCSIFINFO_IN6: 1513 /* 1514 * used to change host variables from userland. 1515 * intented for a use on router to reflect RA configurations. 1516 */ 1517 /* 0 means 'unspecified' */ 1518 if (ND.linkmtu != 0) { 1519 if (ND.linkmtu < IPV6_MMTU || 1520 ND.linkmtu > IN6_LINKMTU(ifp)) { 1521 error = EINVAL; 1522 break; 1523 } 1524 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1525 } 1526 1527 if (ND.basereachable != 0) { 1528 int obasereachable = ND_IFINFO(ifp)->basereachable; 1529 1530 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1531 if (ND.basereachable != obasereachable) 1532 ND_IFINFO(ifp)->reachable = 1533 ND_COMPUTE_RTIME(ND.basereachable); 1534 } 1535 if (ND.retrans != 0) 1536 ND_IFINFO(ifp)->retrans = ND.retrans; 1537 if (ND.chlim != 0) 1538 ND_IFINFO(ifp)->chlim = ND.chlim; 1539 /* FALLTHROUGH */ 1540 case SIOCSIFINFO_FLAGS: 1541 ND_IFINFO(ifp)->flags = ND.flags; 1542 break; 1543 #undef ND 1544 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1545 /* sync kernel routing table with the default router list */ 1546 defrouter_reset(); 1547 defrouter_select(); 1548 break; 1549 case SIOCSPFXFLUSH_IN6: 1550 { 1551 /* flush all the prefix advertised by routers */ 1552 struct nd_prefix *pfx, *next; 1553 1554 s = splsoftnet(); 1555 for (pfx = nd_prefix.lh_first; pfx; pfx = next) { 1556 struct in6_ifaddr *ia, *ia_next; 1557 1558 next = pfx->ndpr_next; 1559 1560 if (IN6_IS_ADDR_LINKLOCAL(&pfx->ndpr_prefix.sin6_addr)) 1561 continue; /* XXX */ 1562 1563 /* do we really have to remove addresses as well? */ 1564 for (ia = in6_ifaddr; ia; ia = ia_next) { 1565 /* ia might be removed. keep the next ptr. */ 1566 ia_next = ia->ia_next; 1567 1568 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1569 continue; 1570 1571 if (ia->ia6_ndpr == pfx) 1572 in6_purgeaddr(&ia->ia_ifa); 1573 } 1574 prelist_remove(pfx); 1575 } 1576 splx(s); 1577 break; 1578 } 1579 case SIOCSRTRFLUSH_IN6: 1580 { 1581 /* flush all the default routers */ 1582 struct nd_defrouter *drtr, *next; 1583 1584 s = splsoftnet(); 1585 defrouter_reset(); 1586 for (drtr = TAILQ_FIRST(&nd_defrouter); drtr; drtr = next) { 1587 next = TAILQ_NEXT(drtr, dr_entry); 1588 defrtrlist_del(drtr); 1589 } 1590 defrouter_select(); 1591 splx(s); 1592 break; 1593 } 1594 case SIOCGNBRINFO_IN6: 1595 { 1596 struct llinfo_nd6 *ln; 1597 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1598 1599 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1600 return (error); 1601 1602 s = splsoftnet(); 1603 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL || 1604 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) { 1605 error = EINVAL; 1606 splx(s); 1607 break; 1608 } 1609 nbi->state = ln->ln_state; 1610 nbi->asked = ln->ln_asked; 1611 nbi->isrouter = ln->ln_router; 1612 nbi->expire = ln->ln_expire; 1613 splx(s); 1614 1615 break; 1616 } 1617 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1618 ndif->ifindex = nd6_defifindex; 1619 break; 1620 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1621 return (nd6_setdefaultiface(ndif->ifindex)); 1622 } 1623 return (error); 1624 } 1625 1626 /* 1627 * Create neighbor cache entry and cache link-layer address, 1628 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1629 */ 1630 struct rtentry * 1631 nd6_cache_lladdr(ifp, from, lladdr, lladdrlen, type, code) 1632 struct ifnet *ifp; 1633 struct in6_addr *from; 1634 char *lladdr; 1635 int lladdrlen; 1636 int type; /* ICMP6 type */ 1637 int code; /* type dependent information */ 1638 { 1639 struct rtentry *rt = NULL; 1640 struct llinfo_nd6 *ln = NULL; 1641 int is_newentry; 1642 struct sockaddr_dl *sdl = NULL; 1643 int do_update; 1644 int olladdr; 1645 int llchange; 1646 int newstate = 0; 1647 1648 if (ifp == NULL) 1649 panic("ifp == NULL in nd6_cache_lladdr"); 1650 if (from == NULL) 1651 panic("from == NULL in nd6_cache_lladdr"); 1652 1653 /* nothing must be updated for unspecified address */ 1654 if (IN6_IS_ADDR_UNSPECIFIED(from)) 1655 return NULL; 1656 1657 /* 1658 * Validation about ifp->if_addrlen and lladdrlen must be done in 1659 * the caller. 1660 * 1661 * XXX If the link does not have link-layer adderss, what should 1662 * we do? (ifp->if_addrlen == 0) 1663 * Spec says nothing in sections for RA, RS and NA. There's small 1664 * description on it in NS section (RFC 2461 7.2.3). 1665 */ 1666 1667 rt = nd6_lookup(from, 0, ifp); 1668 if (rt == NULL) { 1669 #if 0 1670 /* nothing must be done if there's no lladdr */ 1671 if (!lladdr || !lladdrlen) 1672 return NULL; 1673 #endif 1674 1675 rt = nd6_lookup(from, 1, ifp); 1676 is_newentry = 1; 1677 } else { 1678 /* do nothing if static ndp is set */ 1679 if (rt->rt_flags & RTF_STATIC) 1680 return NULL; 1681 is_newentry = 0; 1682 } 1683 1684 if (rt == NULL) 1685 return NULL; 1686 if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) { 1687 fail: 1688 (void)nd6_free(rt, 0); 1689 return NULL; 1690 } 1691 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1692 if (ln == NULL) 1693 goto fail; 1694 if (rt->rt_gateway == NULL) 1695 goto fail; 1696 if (rt->rt_gateway->sa_family != AF_LINK) 1697 goto fail; 1698 sdl = SDL(rt->rt_gateway); 1699 1700 olladdr = (sdl->sdl_alen) ? 1 : 0; 1701 if (olladdr && lladdr) { 1702 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 1703 llchange = 1; 1704 else 1705 llchange = 0; 1706 } else 1707 llchange = 0; 1708 1709 /* 1710 * newentry olladdr lladdr llchange (*=record) 1711 * 0 n n -- (1) 1712 * 0 y n -- (2) 1713 * 0 n y -- (3) * STALE 1714 * 0 y y n (4) * 1715 * 0 y y y (5) * STALE 1716 * 1 -- n -- (6) NOSTATE(= PASSIVE) 1717 * 1 -- y -- (7) * STALE 1718 */ 1719 1720 if (lladdr) { /* (3-5) and (7) */ 1721 /* 1722 * Record source link-layer address 1723 * XXX is it dependent to ifp->if_type? 1724 */ 1725 sdl->sdl_alen = ifp->if_addrlen; 1726 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 1727 } 1728 1729 if (!is_newentry) { 1730 if ((!olladdr && lladdr) || /* (3) */ 1731 (olladdr && lladdr && llchange)) { /* (5) */ 1732 do_update = 1; 1733 newstate = ND6_LLINFO_STALE; 1734 } else /* (1-2,4) */ 1735 do_update = 0; 1736 } else { 1737 do_update = 1; 1738 if (lladdr == NULL) /* (6) */ 1739 newstate = ND6_LLINFO_NOSTATE; 1740 else /* (7) */ 1741 newstate = ND6_LLINFO_STALE; 1742 } 1743 1744 if (do_update) { 1745 /* 1746 * Update the state of the neighbor cache. 1747 */ 1748 ln->ln_state = newstate; 1749 1750 if (ln->ln_state == ND6_LLINFO_STALE) { 1751 /* 1752 * XXX: since nd6_output() below will cause 1753 * state tansition to DELAY and reset the timer, 1754 * we must set the timer now, although it is actually 1755 * meaningless. 1756 */ 1757 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1758 1759 if (ln->ln_hold) { 1760 struct mbuf *m_hold, *m_hold_next; 1761 for (m_hold = ln->ln_hold; m_hold; 1762 m_hold = m_hold_next) { 1763 struct mbuf *mpkt = NULL; 1764 1765 m_hold_next = m_hold->m_nextpkt; 1766 mpkt = m_copym(m_hold, 0, M_COPYALL, M_DONTWAIT); 1767 if (mpkt == NULL) { 1768 m_freem(m_hold); 1769 break; 1770 } 1771 mpkt->m_nextpkt = NULL; 1772 1773 /* 1774 * we assume ifp is not a p2p here, so 1775 * just set the 2nd argument as the 1776 * 1st one. 1777 */ 1778 nd6_output(ifp, ifp, mpkt, 1779 (struct sockaddr_in6 *)rt_key(rt), 1780 rt); 1781 } 1782 ln->ln_hold = NULL; 1783 } 1784 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 1785 /* probe right away */ 1786 nd6_llinfo_settimer((void *)ln, 0); 1787 } 1788 } 1789 1790 /* 1791 * ICMP6 type dependent behavior. 1792 * 1793 * NS: clear IsRouter if new entry 1794 * RS: clear IsRouter 1795 * RA: set IsRouter if there's lladdr 1796 * redir: clear IsRouter if new entry 1797 * 1798 * RA case, (1): 1799 * The spec says that we must set IsRouter in the following cases: 1800 * - If lladdr exist, set IsRouter. This means (1-5). 1801 * - If it is old entry (!newentry), set IsRouter. This means (7). 1802 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1803 * A quetion arises for (1) case. (1) case has no lladdr in the 1804 * neighbor cache, this is similar to (6). 1805 * This case is rare but we figured that we MUST NOT set IsRouter. 1806 * 1807 * newentry olladdr lladdr llchange NS RS RA redir 1808 * D R 1809 * 0 n n -- (1) c ? s 1810 * 0 y n -- (2) c s s 1811 * 0 n y -- (3) c s s 1812 * 0 y y n (4) c s s 1813 * 0 y y y (5) c s s 1814 * 1 -- n -- (6) c c c s 1815 * 1 -- y -- (7) c c s c s 1816 * 1817 * (c=clear s=set) 1818 */ 1819 switch (type & 0xff) { 1820 case ND_NEIGHBOR_SOLICIT: 1821 /* 1822 * New entry must have is_router flag cleared. 1823 */ 1824 if (is_newentry) /* (6-7) */ 1825 ln->ln_router = 0; 1826 break; 1827 case ND_REDIRECT: 1828 /* 1829 * If the icmp is a redirect to a better router, always set the 1830 * is_router flag. Otherwise, if the entry is newly created, 1831 * clear the flag. [RFC 2461, sec 8.3] 1832 */ 1833 if (code == ND_REDIRECT_ROUTER) 1834 ln->ln_router = 1; 1835 else if (is_newentry) /* (6-7) */ 1836 ln->ln_router = 0; 1837 break; 1838 case ND_ROUTER_SOLICIT: 1839 /* 1840 * is_router flag must always be cleared. 1841 */ 1842 ln->ln_router = 0; 1843 break; 1844 case ND_ROUTER_ADVERT: 1845 /* 1846 * Mark an entry with lladdr as a router. 1847 */ 1848 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */ 1849 (is_newentry && lladdr)) { /* (7) */ 1850 ln->ln_router = 1; 1851 } 1852 break; 1853 } 1854 1855 /* 1856 * When the link-layer address of a router changes, select the 1857 * best router again. In particular, when the neighbor entry is newly 1858 * created, it might affect the selection policy. 1859 * Question: can we restrict the first condition to the "is_newentry" 1860 * case? 1861 * XXX: when we hear an RA from a new router with the link-layer 1862 * address option, defrouter_select() is called twice, since 1863 * defrtrlist_update called the function as well. However, I believe 1864 * we can compromise the overhead, since it only happens the first 1865 * time. 1866 * XXX: although defrouter_select() should not have a bad effect 1867 * for those are not autoconfigured hosts, we explicitly avoid such 1868 * cases for safety. 1869 */ 1870 if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv) 1871 defrouter_select(); 1872 1873 return rt; 1874 } 1875 1876 static void 1877 nd6_slowtimo(ignored_arg) 1878 void *ignored_arg; 1879 { 1880 int s = splsoftnet(); 1881 struct nd_ifinfo *nd6if; 1882 struct ifnet *ifp; 1883 1884 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 1885 nd6_slowtimo, NULL); 1886 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1887 { 1888 nd6if = ND_IFINFO(ifp); 1889 if (nd6if->basereachable && /* already initialized */ 1890 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 1891 /* 1892 * Since reachable time rarely changes by router 1893 * advertisements, we SHOULD insure that a new random 1894 * value gets recomputed at least once every few hours. 1895 * (RFC 2461, 6.3.4) 1896 */ 1897 nd6if->recalctm = nd6_recalc_reachtm_interval; 1898 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 1899 } 1900 } 1901 splx(s); 1902 } 1903 1904 #define senderr(e) { error = (e); goto bad;} 1905 int 1906 nd6_output(ifp, origifp, m0, dst, rt0) 1907 struct ifnet *ifp; 1908 struct ifnet *origifp; 1909 struct mbuf *m0; 1910 struct sockaddr_in6 *dst; 1911 struct rtentry *rt0; 1912 { 1913 struct mbuf *m = m0; 1914 struct rtentry *rt = rt0; 1915 struct sockaddr_in6 *gw6 = NULL; 1916 struct llinfo_nd6 *ln = NULL; 1917 int error = 0; 1918 1919 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr)) 1920 goto sendpkt; 1921 1922 if (nd6_need_cache(ifp) == 0) 1923 goto sendpkt; 1924 1925 /* 1926 * next hop determination. This routine is derived from ether_output. 1927 */ 1928 if (rt) { 1929 if ((rt->rt_flags & RTF_UP) == 0) { 1930 if ((rt0 = rt = rtalloc1((struct sockaddr *)dst, 1931 1)) != NULL) 1932 { 1933 rt->rt_refcnt--; 1934 if (rt->rt_ifp != ifp) 1935 senderr(EHOSTUNREACH); 1936 } else 1937 senderr(EHOSTUNREACH); 1938 } 1939 1940 if (rt->rt_flags & RTF_GATEWAY) { 1941 gw6 = (struct sockaddr_in6 *)rt->rt_gateway; 1942 1943 /* 1944 * We skip link-layer address resolution and NUD 1945 * if the gateway is not a neighbor from ND point 1946 * of view, regardless of the value of nd_ifinfo.flags. 1947 * The second condition is a bit tricky; we skip 1948 * if the gateway is our own address, which is 1949 * sometimes used to install a route to a p2p link. 1950 */ 1951 if (!nd6_is_addr_neighbor(gw6, ifp) || 1952 in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) { 1953 /* 1954 * We allow this kind of tricky route only 1955 * when the outgoing interface is p2p. 1956 * XXX: we may need a more generic rule here. 1957 */ 1958 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 1959 senderr(EHOSTUNREACH); 1960 1961 goto sendpkt; 1962 } 1963 1964 if (rt->rt_gwroute == 0) 1965 goto lookup; 1966 if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) { 1967 rtfree(rt); rt = rt0; 1968 lookup: 1969 rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1); 1970 if ((rt = rt->rt_gwroute) == 0) 1971 senderr(EHOSTUNREACH); 1972 /* the "G" test below also prevents rt == rt0 */ 1973 if ((rt->rt_flags & RTF_GATEWAY) || 1974 (rt->rt_ifp != ifp)) { 1975 rt->rt_refcnt--; 1976 rt0->rt_gwroute = 0; 1977 senderr(EHOSTUNREACH); 1978 } 1979 } 1980 } 1981 } 1982 1983 /* 1984 * Address resolution or Neighbor Unreachability Detection 1985 * for the next hop. 1986 * At this point, the destination of the packet must be a unicast 1987 * or an anycast address(i.e. not a multicast). 1988 */ 1989 1990 /* Look up the neighbor cache for the nexthop */ 1991 if (rt && (rt->rt_flags & RTF_LLINFO) != 0) 1992 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1993 else { 1994 /* 1995 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 1996 * the condition below is not very efficient. But we believe 1997 * it is tolerable, because this should be a rare case. 1998 */ 1999 if (nd6_is_addr_neighbor(dst, ifp) && 2000 (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL) 2001 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2002 } 2003 if (ln == NULL || rt == NULL) { 2004 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 && 2005 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { 2006 log(LOG_DEBUG, 2007 "nd6_output: can't allocate llinfo for %s " 2008 "(ln=%p, rt=%p)\n", 2009 ip6_sprintf(&dst->sin6_addr), ln, rt); 2010 senderr(EIO); /* XXX: good error? */ 2011 } 2012 2013 goto sendpkt; /* send anyway */ 2014 } 2015 2016 /* We don't have to do link-layer address resolution on a p2p link. */ 2017 if ((ifp->if_flags & IFF_POINTOPOINT) != 0 && 2018 ln->ln_state < ND6_LLINFO_REACHABLE) { 2019 ln->ln_state = ND6_LLINFO_STALE; 2020 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 2021 } 2022 2023 /* 2024 * The first time we send a packet to a neighbor whose entry is 2025 * STALE, we have to change the state to DELAY and a sets a timer to 2026 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2027 * neighbor unreachability detection on expiration. 2028 * (RFC 2461 7.3.3) 2029 */ 2030 if (ln->ln_state == ND6_LLINFO_STALE) { 2031 ln->ln_asked = 0; 2032 ln->ln_state = ND6_LLINFO_DELAY; 2033 nd6_llinfo_settimer(ln, (long)nd6_delay * hz); 2034 } 2035 2036 /* 2037 * If the neighbor cache entry has a state other than INCOMPLETE 2038 * (i.e. its link-layer address is already resolved), just 2039 * send the packet. 2040 */ 2041 if (ln->ln_state > ND6_LLINFO_INCOMPLETE) 2042 goto sendpkt; 2043 2044 /* 2045 * There is a neighbor cache entry, but no ethernet address 2046 * response yet. Append this latest packet to the end of the 2047 * packet queue in the mbuf, unless the number of the packet 2048 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, 2049 * the oldest packet in the queue will be removed. 2050 */ 2051 if (ln->ln_state == ND6_LLINFO_NOSTATE) 2052 ln->ln_state = ND6_LLINFO_INCOMPLETE; 2053 if (ln->ln_hold) { 2054 struct mbuf *m_hold; 2055 int i; 2056 2057 i = 0; 2058 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold->m_nextpkt) { 2059 i++; 2060 if (m_hold->m_nextpkt == NULL) { 2061 m_hold->m_nextpkt = m; 2062 break; 2063 } 2064 } 2065 while (i >= nd6_maxqueuelen) { 2066 m_hold = ln->ln_hold; 2067 ln->ln_hold = ln->ln_hold->m_nextpkt; 2068 m_freem(m_hold); 2069 i--; 2070 } 2071 } else { 2072 ln->ln_hold = m; 2073 } 2074 2075 /* 2076 * If there has been no NS for the neighbor after entering the 2077 * INCOMPLETE state, send the first solicitation. 2078 */ 2079 if (!ND6_LLINFO_PERMANENT(ln) && ln->ln_asked == 0) { 2080 ln->ln_asked++; 2081 nd6_llinfo_settimer(ln, 2082 (long)ND_IFINFO(ifp)->retrans * hz / 1000); 2083 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 2084 } 2085 return (0); 2086 2087 sendpkt: 2088 /* discard the packet if IPv6 operation is disabled on the interface */ 2089 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 2090 error = ENETDOWN; /* better error? */ 2091 goto bad; 2092 } 2093 2094 #ifdef IPSEC 2095 /* clean ipsec history once it goes out of the node */ 2096 ipsec_delaux(m); 2097 #endif 2098 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 2099 return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst, 2100 rt)); 2101 } 2102 return ((*ifp->if_output)(ifp, m, (struct sockaddr *)dst, rt)); 2103 2104 bad: 2105 if (m) 2106 m_freem(m); 2107 return (error); 2108 } 2109 #undef senderr 2110 2111 int 2112 nd6_need_cache(ifp) 2113 struct ifnet *ifp; 2114 { 2115 /* 2116 * XXX: we currently do not make neighbor cache on any interface 2117 * other than ARCnet, Ethernet, FDDI and GIF. 2118 * 2119 * RFC2893 says: 2120 * - unidirectional tunnels needs no ND 2121 */ 2122 switch (ifp->if_type) { 2123 case IFT_ARCNET: 2124 case IFT_ETHER: 2125 case IFT_FDDI: 2126 case IFT_IEEE1394: 2127 case IFT_CARP: 2128 case IFT_GIF: /* XXX need more cases? */ 2129 case IFT_PPP: 2130 case IFT_TUNNEL: 2131 return (1); 2132 default: 2133 return (0); 2134 } 2135 } 2136 2137 int 2138 nd6_storelladdr(ifp, rt, m, dst, desten) 2139 struct ifnet *ifp; 2140 struct rtentry *rt; 2141 struct mbuf *m; 2142 struct sockaddr *dst; 2143 u_char *desten; 2144 { 2145 struct sockaddr_dl *sdl; 2146 2147 if (m->m_flags & M_MCAST) { 2148 switch (ifp->if_type) { 2149 case IFT_ETHER: 2150 case IFT_FDDI: 2151 ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr, 2152 desten); 2153 return (1); 2154 case IFT_IEEE1394: 2155 bcopy(ifp->if_broadcastaddr, desten, ifp->if_addrlen); 2156 return (1); 2157 case IFT_ARCNET: 2158 *desten = 0; 2159 return (1); 2160 default: 2161 m_freem(m); 2162 return (0); 2163 } 2164 } 2165 2166 if (rt == NULL) { 2167 /* this could happen, if we could not allocate memory */ 2168 m_freem(m); 2169 return (0); 2170 } 2171 if (rt->rt_gateway->sa_family != AF_LINK) { 2172 printf("nd6_storelladdr: something odd happens\n"); 2173 m_freem(m); 2174 return (0); 2175 } 2176 sdl = SDL(rt->rt_gateway); 2177 if (sdl->sdl_alen == 0) { 2178 /* this should be impossible, but we bark here for debugging */ 2179 printf("nd6_storelladdr: sdl_alen == 0, dst=%s, if=%s\n", 2180 ip6_sprintf(&SIN6(dst)->sin6_addr), if_name(ifp)); 2181 m_freem(m); 2182 return (0); 2183 } 2184 2185 bcopy(LLADDR(sdl), desten, sdl->sdl_alen); 2186 return (1); 2187 } 2188 2189 static void 2190 clear_llinfo_pqueue(ln) 2191 struct llinfo_nd6 *ln; 2192 { 2193 struct mbuf *m_hold, *m_hold_next; 2194 2195 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold_next) { 2196 m_hold_next = m_hold->m_nextpkt; 2197 m_hold->m_nextpkt = NULL; 2198 m_freem(m_hold); 2199 } 2200 2201 ln->ln_hold = NULL; 2202 return; 2203 } 2204 2205 int 2206 nd6_sysctl(name, oldp, oldlenp, newp, newlen) 2207 int name; 2208 void *oldp; /* syscall arg, need copyout */ 2209 size_t *oldlenp; 2210 void *newp; /* syscall arg, need copyin */ 2211 size_t newlen; 2212 { 2213 void *p; 2214 size_t ol; 2215 int error; 2216 2217 error = 0; 2218 2219 if (newp) 2220 return EPERM; 2221 if (oldp && !oldlenp) 2222 return EINVAL; 2223 ol = oldlenp ? *oldlenp : 0; 2224 2225 if (oldp) { 2226 p = malloc(*oldlenp, M_TEMP, M_WAITOK); 2227 if (p == NULL) 2228 return ENOMEM; 2229 } else 2230 p = NULL; 2231 switch (name) { 2232 case ICMPV6CTL_ND6_DRLIST: 2233 error = fill_drlist(p, oldlenp, ol); 2234 if (!error && p != NULL && oldp != NULL) 2235 error = copyout(p, oldp, *oldlenp); 2236 break; 2237 2238 case ICMPV6CTL_ND6_PRLIST: 2239 error = fill_prlist(p, oldlenp, ol); 2240 if (!error && p != NULL && oldp != NULL) 2241 error = copyout(p, oldp, *oldlenp); 2242 break; 2243 2244 case ICMPV6CTL_ND6_MAXQLEN: 2245 break; 2246 2247 default: 2248 error = ENOPROTOOPT; 2249 break; 2250 } 2251 if (p) 2252 free(p, M_TEMP); 2253 2254 return (error); 2255 } 2256 2257 static int 2258 fill_drlist(oldp, oldlenp, ol) 2259 void *oldp; 2260 size_t *oldlenp, ol; 2261 { 2262 int error = 0, s; 2263 struct in6_defrouter *d = NULL, *de = NULL; 2264 struct nd_defrouter *dr; 2265 size_t l; 2266 2267 s = splsoftnet(); 2268 2269 if (oldp) { 2270 d = (struct in6_defrouter *)oldp; 2271 de = (struct in6_defrouter *)((caddr_t)oldp + *oldlenp); 2272 } 2273 l = 0; 2274 2275 for (dr = TAILQ_FIRST(&nd_defrouter); dr; 2276 dr = TAILQ_NEXT(dr, dr_entry)) { 2277 2278 if (oldp && d + 1 <= de) { 2279 bzero(d, sizeof(*d)); 2280 d->rtaddr.sin6_family = AF_INET6; 2281 d->rtaddr.sin6_len = sizeof(struct sockaddr_in6); 2282 d->rtaddr.sin6_addr = dr->rtaddr; 2283 if (sa6_recoverscope(&d->rtaddr)) { 2284 log(LOG_ERR, 2285 "scope error in router list (%s)\n", 2286 ip6_sprintf(&d->rtaddr.sin6_addr)); 2287 /* XXX: press on... */ 2288 } 2289 d->flags = dr->flags; 2290 d->rtlifetime = dr->rtlifetime; 2291 d->expire = dr->expire; 2292 d->if_index = dr->ifp->if_index; 2293 } 2294 2295 l += sizeof(*d); 2296 if (d) 2297 d++; 2298 } 2299 2300 if (oldp) { 2301 if (l > ol) 2302 error = ENOMEM; 2303 } 2304 if (oldlenp) 2305 *oldlenp = l; /* (caddr_t)d - (caddr_t)oldp */ 2306 2307 splx(s); 2308 2309 return (error); 2310 } 2311 2312 static int 2313 fill_prlist(oldp, oldlenp, ol) 2314 void *oldp; 2315 size_t *oldlenp, ol; 2316 { 2317 int error = 0, s; 2318 struct nd_prefix *pr; 2319 struct in6_prefix *p = NULL; 2320 struct in6_prefix *pe = NULL; 2321 size_t l; 2322 2323 s = splsoftnet(); 2324 2325 if (oldp) { 2326 p = (struct in6_prefix *)oldp; 2327 pe = (struct in6_prefix *)((caddr_t)oldp + *oldlenp); 2328 } 2329 l = 0; 2330 2331 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 2332 u_short advrtrs; 2333 size_t advance; 2334 struct sockaddr_in6 *sin6; 2335 struct sockaddr_in6 *s6; 2336 struct nd_pfxrouter *pfr; 2337 2338 if (oldp && p + 1 <= pe) 2339 { 2340 bzero(p, sizeof(*p)); 2341 sin6 = (struct sockaddr_in6 *)(p + 1); 2342 2343 p->prefix = pr->ndpr_prefix; 2344 if (sa6_recoverscope(&p->prefix)) { 2345 log(LOG_ERR, 2346 "scope error in prefix list (%s)\n", 2347 ip6_sprintf(&p->prefix.sin6_addr)); 2348 /* XXX: press on... */ 2349 } 2350 p->raflags = pr->ndpr_raf; 2351 p->prefixlen = pr->ndpr_plen; 2352 p->vltime = pr->ndpr_vltime; 2353 p->pltime = pr->ndpr_pltime; 2354 p->if_index = pr->ndpr_ifp->if_index; 2355 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2356 p->expire = 0; 2357 else { 2358 time_t maxexpire; 2359 2360 /* XXX: we assume time_t is signed. */ 2361 maxexpire = (-1) & 2362 ~((time_t)1 << 2363 ((sizeof(maxexpire) * 8) - 1)); 2364 if (pr->ndpr_vltime < 2365 maxexpire - pr->ndpr_lastupdate) { 2366 p->expire = pr->ndpr_lastupdate + 2367 pr->ndpr_vltime; 2368 } else 2369 p->expire = maxexpire; 2370 } 2371 p->refcnt = pr->ndpr_refcnt; 2372 p->flags = pr->ndpr_stateflags; 2373 p->origin = PR_ORIG_RA; 2374 advrtrs = 0; 2375 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2376 pfr = pfr->pfr_next) { 2377 if ((void *)&sin6[advrtrs + 1] > (void *)pe) { 2378 advrtrs++; 2379 continue; 2380 } 2381 s6 = &sin6[advrtrs]; 2382 s6->sin6_family = AF_INET6; 2383 s6->sin6_len = sizeof(struct sockaddr_in6); 2384 s6->sin6_addr = pfr->router->rtaddr; 2385 s6->sin6_scope_id = 0; 2386 if (sa6_recoverscope(s6)) { 2387 log(LOG_ERR, 2388 "scope error in " 2389 "prefix list (%s)\n", 2390 ip6_sprintf(&pfr->router->rtaddr)); 2391 } 2392 advrtrs++; 2393 } 2394 p->advrtrs = advrtrs; 2395 } 2396 else { 2397 advrtrs = 0; 2398 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2399 pfr = pfr->pfr_next) 2400 advrtrs++; 2401 } 2402 2403 advance = sizeof(*p) + sizeof(*sin6) * advrtrs; 2404 l += advance; 2405 if (p) 2406 p = (struct in6_prefix *)((caddr_t)p + advance); 2407 } 2408 2409 if (oldp) { 2410 *oldlenp = l; /* (caddr_t)d - (caddr_t)oldp */ 2411 if (l > ol) 2412 error = ENOMEM; 2413 } else 2414 *oldlenp = l; 2415 2416 splx(s); 2417 2418 return (error); 2419 } 2420