1 /* $NetBSD: nd6.c,v 1.104 2006/09/02 07:22:44 christos 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 1.104 2006/09/02 07:22:44 christos 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 = { 106 .ln_prev = &llinfo_nd6, 107 .ln_next = &llinfo_nd6, 108 }; 109 struct nd_drhead nd_defrouter; 110 struct nd_prhead nd_prefix = { 0 }; 111 112 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL; 113 static struct sockaddr_in6 all1_sa; 114 115 static void nd6_setmtu0 __P((struct ifnet *, struct nd_ifinfo *)); 116 static void nd6_slowtimo __P((void *)); 117 static int regen_tmpaddr __P((struct in6_ifaddr *)); 118 static struct llinfo_nd6 *nd6_free __P((struct rtentry *, int)); 119 static void nd6_llinfo_timer __P((void *)); 120 static void clear_llinfo_pqueue __P((struct llinfo_nd6 *)); 121 122 struct callout nd6_slowtimo_ch = CALLOUT_INITIALIZER; 123 struct callout nd6_timer_ch = CALLOUT_INITIALIZER; 124 extern struct callout in6_tmpaddrtimer_ch; 125 126 static int fill_drlist __P((void *, size_t *, size_t)); 127 static int fill_prlist __P((void *, size_t *, size_t)); 128 129 MALLOC_DEFINE(M_IP6NDP, "NDP", "IPv6 Neighbour Discovery"); 130 131 void 132 nd6_init() 133 { 134 static int nd6_init_done = 0; 135 int i; 136 137 if (nd6_init_done) { 138 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n"); 139 return; 140 } 141 142 all1_sa.sin6_family = AF_INET6; 143 all1_sa.sin6_len = sizeof(struct sockaddr_in6); 144 for (i = 0; i < sizeof(all1_sa.sin6_addr); i++) 145 all1_sa.sin6_addr.s6_addr[i] = 0xff; 146 147 /* initialization of the default router list */ 148 TAILQ_INIT(&nd_defrouter); 149 150 nd6_init_done = 1; 151 152 /* start timer */ 153 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 154 nd6_slowtimo, NULL); 155 } 156 157 struct nd_ifinfo * 158 nd6_ifattach(ifp) 159 struct ifnet *ifp; 160 { 161 struct nd_ifinfo *nd; 162 163 nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK); 164 bzero(nd, sizeof(*nd)); 165 166 nd->initialized = 1; 167 168 nd->chlim = IPV6_DEFHLIM; 169 nd->basereachable = REACHABLE_TIME; 170 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 171 nd->retrans = RETRANS_TIMER; 172 /* 173 * Note that the default value of ip6_accept_rtadv is 0, which means 174 * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV 175 * here. 176 */ 177 nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV); 178 179 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 180 nd6_setmtu0(ifp, nd); 181 182 return nd; 183 } 184 185 void 186 nd6_ifdetach(nd) 187 struct nd_ifinfo *nd; 188 { 189 190 free(nd, M_IP6NDP); 191 } 192 193 void 194 nd6_setmtu(ifp) 195 struct ifnet *ifp; 196 { 197 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 198 } 199 200 void 201 nd6_setmtu0(ifp, ndi) 202 struct ifnet *ifp; 203 struct nd_ifinfo *ndi; 204 { 205 u_int32_t omaxmtu; 206 207 omaxmtu = ndi->maxmtu; 208 209 switch (ifp->if_type) { 210 case IFT_ARCNET: 211 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */ 212 break; 213 case IFT_FDDI: 214 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); 215 break; 216 default: 217 ndi->maxmtu = ifp->if_mtu; 218 break; 219 } 220 221 /* 222 * Decreasing the interface MTU under IPV6 minimum MTU may cause 223 * undesirable situation. We thus notify the operator of the change 224 * explicitly. The check for omaxmtu is necessary to restrict the 225 * log to the case of changing the MTU, not initializing it. 226 */ 227 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 228 log(LOG_NOTICE, "nd6_setmtu0: new link MTU on %s (%lu) is too" 229 " small for IPv6 which needs %lu\n", 230 if_name(ifp), (unsigned long)ndi->maxmtu, (unsigned long) 231 IPV6_MMTU); 232 } 233 234 if (ndi->maxmtu > in6_maxmtu) 235 in6_setmaxmtu(); /* check all interfaces just in case */ 236 } 237 238 void 239 nd6_option_init(opt, icmp6len, ndopts) 240 void *opt; 241 int icmp6len; 242 union nd_opts *ndopts; 243 { 244 245 bzero(ndopts, sizeof(*ndopts)); 246 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 247 ndopts->nd_opts_last 248 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 249 250 if (icmp6len == 0) { 251 ndopts->nd_opts_done = 1; 252 ndopts->nd_opts_search = NULL; 253 } 254 } 255 256 /* 257 * Take one ND option. 258 */ 259 struct nd_opt_hdr * 260 nd6_option(ndopts) 261 union nd_opts *ndopts; 262 { 263 struct nd_opt_hdr *nd_opt; 264 int olen; 265 266 if (ndopts == NULL) 267 panic("ndopts == NULL in nd6_option"); 268 if (ndopts->nd_opts_last == NULL) 269 panic("uninitialized ndopts in nd6_option"); 270 if (ndopts->nd_opts_search == NULL) 271 return NULL; 272 if (ndopts->nd_opts_done) 273 return NULL; 274 275 nd_opt = ndopts->nd_opts_search; 276 277 /* make sure nd_opt_len is inside the buffer */ 278 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { 279 bzero(ndopts, sizeof(*ndopts)); 280 return NULL; 281 } 282 283 olen = nd_opt->nd_opt_len << 3; 284 if (olen == 0) { 285 /* 286 * Message validation requires that all included 287 * options have a length that is greater than zero. 288 */ 289 bzero(ndopts, sizeof(*ndopts)); 290 return NULL; 291 } 292 293 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); 294 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 295 /* option overruns the end of buffer, invalid */ 296 bzero(ndopts, sizeof(*ndopts)); 297 return NULL; 298 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 299 /* reached the end of options chain */ 300 ndopts->nd_opts_done = 1; 301 ndopts->nd_opts_search = NULL; 302 } 303 return nd_opt; 304 } 305 306 /* 307 * Parse multiple ND options. 308 * This function is much easier to use, for ND routines that do not need 309 * multiple options of the same type. 310 */ 311 int 312 nd6_options(ndopts) 313 union nd_opts *ndopts; 314 { 315 struct nd_opt_hdr *nd_opt; 316 int i = 0; 317 318 if (ndopts == NULL) 319 panic("ndopts == NULL in nd6_options"); 320 if (ndopts->nd_opts_last == NULL) 321 panic("uninitialized ndopts in nd6_options"); 322 if (ndopts->nd_opts_search == NULL) 323 return 0; 324 325 while (1) { 326 nd_opt = nd6_option(ndopts); 327 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 328 /* 329 * Message validation requires that all included 330 * options have a length that is greater than zero. 331 */ 332 icmp6stat.icp6s_nd_badopt++; 333 bzero(ndopts, sizeof(*ndopts)); 334 return -1; 335 } 336 337 if (nd_opt == NULL) 338 goto skip1; 339 340 switch (nd_opt->nd_opt_type) { 341 case ND_OPT_SOURCE_LINKADDR: 342 case ND_OPT_TARGET_LINKADDR: 343 case ND_OPT_MTU: 344 case ND_OPT_REDIRECTED_HEADER: 345 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 346 nd6log((LOG_INFO, 347 "duplicated ND6 option found (type=%d)\n", 348 nd_opt->nd_opt_type)); 349 /* XXX bark? */ 350 } else { 351 ndopts->nd_opt_array[nd_opt->nd_opt_type] 352 = nd_opt; 353 } 354 break; 355 case ND_OPT_PREFIX_INFORMATION: 356 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 357 ndopts->nd_opt_array[nd_opt->nd_opt_type] 358 = nd_opt; 359 } 360 ndopts->nd_opts_pi_end = 361 (struct nd_opt_prefix_info *)nd_opt; 362 break; 363 default: 364 /* 365 * Unknown options must be silently ignored, 366 * to accomodate future extension to the protocol. 367 */ 368 nd6log((LOG_DEBUG, 369 "nd6_options: unsupported option %d - " 370 "option ignored\n", nd_opt->nd_opt_type)); 371 } 372 373 skip1: 374 i++; 375 if (i > nd6_maxndopt) { 376 icmp6stat.icp6s_nd_toomanyopt++; 377 nd6log((LOG_INFO, "too many loop in nd opt\n")); 378 break; 379 } 380 381 if (ndopts->nd_opts_done) 382 break; 383 } 384 385 return 0; 386 } 387 388 /* 389 * ND6 timer routine to handle ND6 entries 390 */ 391 void 392 nd6_llinfo_settimer(ln, xtick) 393 struct llinfo_nd6 *ln; 394 long xtick; 395 { 396 int s; 397 398 s = splsoftnet(); 399 400 if (xtick < 0) { 401 ln->ln_expire = 0; 402 ln->ln_ntick = 0; 403 callout_stop(&ln->ln_timer_ch); 404 } else { 405 ln->ln_expire = time_second + xtick / hz; 406 if (xtick > INT_MAX) { 407 ln->ln_ntick = xtick - INT_MAX; 408 callout_reset(&ln->ln_timer_ch, INT_MAX, 409 nd6_llinfo_timer, ln); 410 } else { 411 ln->ln_ntick = 0; 412 callout_reset(&ln->ln_timer_ch, xtick, 413 nd6_llinfo_timer, ln); 414 } 415 } 416 417 splx(s); 418 } 419 420 static void 421 nd6_llinfo_timer(arg) 422 void *arg; 423 { 424 int s; 425 struct llinfo_nd6 *ln; 426 struct rtentry *rt; 427 const struct sockaddr_in6 *dst; 428 struct ifnet *ifp; 429 struct nd_ifinfo *ndi = NULL; 430 431 s = splsoftnet(); 432 433 ln = (struct llinfo_nd6 *)arg; 434 435 if (ln->ln_ntick > 0) { 436 nd6_llinfo_settimer(ln, ln->ln_ntick); 437 splx(s); 438 return; 439 } 440 441 if ((rt = ln->ln_rt) == NULL) 442 panic("ln->ln_rt == NULL"); 443 if ((ifp = rt->rt_ifp) == NULL) 444 panic("ln->ln_rt->rt_ifp == NULL"); 445 ndi = ND_IFINFO(ifp); 446 dst = (struct sockaddr_in6 *)rt_key(rt); 447 448 /* sanity check */ 449 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln) 450 panic("rt_llinfo(%p) is not equal to ln(%p)", 451 rt->rt_llinfo, ln); 452 if (!dst) 453 panic("dst=0 in nd6_timer(ln=%p)", ln); 454 455 switch (ln->ln_state) { 456 case ND6_LLINFO_INCOMPLETE: 457 if (ln->ln_asked < nd6_mmaxtries) { 458 ln->ln_asked++; 459 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 460 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 461 } else { 462 struct mbuf *m = ln->ln_hold; 463 if (m) { 464 struct mbuf *m0; 465 466 /* 467 * assuming every packet in ln_hold has 468 * the same IP header 469 */ 470 m0 = m->m_nextpkt; 471 m->m_nextpkt = NULL; 472 icmp6_error2(m, ICMP6_DST_UNREACH, 473 ICMP6_DST_UNREACH_ADDR, 0, rt->rt_ifp); 474 475 ln->ln_hold = m0; 476 clear_llinfo_pqueue(ln); 477 } 478 (void)nd6_free(rt, 0); 479 ln = NULL; 480 } 481 break; 482 case ND6_LLINFO_REACHABLE: 483 if (!ND6_LLINFO_PERMANENT(ln)) { 484 ln->ln_state = ND6_LLINFO_STALE; 485 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 486 } 487 break; 488 489 case ND6_LLINFO_STALE: 490 /* Garbage Collection(RFC 2461 5.3) */ 491 if (!ND6_LLINFO_PERMANENT(ln)) { 492 (void)nd6_free(rt, 1); 493 ln = NULL; 494 } 495 break; 496 497 case ND6_LLINFO_DELAY: 498 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 499 /* We need NUD */ 500 ln->ln_asked = 1; 501 ln->ln_state = ND6_LLINFO_PROBE; 502 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 503 nd6_ns_output(ifp, &dst->sin6_addr, 504 &dst->sin6_addr, ln, 0); 505 } else { 506 ln->ln_state = ND6_LLINFO_STALE; /* XXX */ 507 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 508 } 509 break; 510 case ND6_LLINFO_PROBE: 511 if (ln->ln_asked < nd6_umaxtries) { 512 ln->ln_asked++; 513 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 514 nd6_ns_output(ifp, &dst->sin6_addr, 515 &dst->sin6_addr, ln, 0); 516 } else { 517 (void)nd6_free(rt, 0); 518 ln = NULL; 519 } 520 break; 521 } 522 523 splx(s); 524 } 525 526 /* 527 * ND6 timer routine to expire default route list and prefix list 528 */ 529 void 530 nd6_timer(ignored_arg) 531 void *ignored_arg; 532 { 533 int s; 534 struct nd_defrouter *dr; 535 struct nd_prefix *pr; 536 struct in6_ifaddr *ia6, *nia6; 537 struct in6_addrlifetime *lt6; 538 539 s = splsoftnet(); 540 callout_reset(&nd6_timer_ch, nd6_prune * hz, 541 nd6_timer, NULL); 542 543 /* expire default router list */ 544 dr = TAILQ_FIRST(&nd_defrouter); 545 while (dr) { 546 if (dr->expire && dr->expire < time_second) { 547 struct nd_defrouter *t; 548 t = TAILQ_NEXT(dr, dr_entry); 549 defrtrlist_del(dr); 550 dr = t; 551 } else { 552 dr = TAILQ_NEXT(dr, dr_entry); 553 } 554 } 555 556 /* 557 * expire interface addresses. 558 * in the past the loop was inside prefix expiry processing. 559 * However, from a stricter speci-confrmance standpoint, we should 560 * rather separate address lifetimes and prefix lifetimes. 561 */ 562 addrloop: 563 for (ia6 = in6_ifaddr; ia6; ia6 = nia6) { 564 nia6 = ia6->ia_next; 565 /* check address lifetime */ 566 lt6 = &ia6->ia6_lifetime; 567 if (IFA6_IS_INVALID(ia6)) { 568 int regen = 0; 569 570 /* 571 * If the expiring address is temporary, try 572 * regenerating a new one. This would be useful when 573 * we suspended a laptop PC, then turned it on after a 574 * period that could invalidate all temporary 575 * addresses. Although we may have to restart the 576 * loop (see below), it must be after purging the 577 * address. Otherwise, we'd see an infinite loop of 578 * regeneration. 579 */ 580 if (ip6_use_tempaddr && 581 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 582 if (regen_tmpaddr(ia6) == 0) 583 regen = 1; 584 } 585 586 in6_purgeaddr(&ia6->ia_ifa); 587 588 if (regen) 589 goto addrloop; /* XXX: see below */ 590 } else if (IFA6_IS_DEPRECATED(ia6)) { 591 int oldflags = ia6->ia6_flags; 592 593 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 594 595 /* 596 * If a temporary address has just become deprecated, 597 * regenerate a new one if possible. 598 */ 599 if (ip6_use_tempaddr && 600 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 601 (oldflags & IN6_IFF_DEPRECATED) == 0) { 602 603 if (regen_tmpaddr(ia6) == 0) { 604 /* 605 * A new temporary address is 606 * generated. 607 * XXX: this means the address chain 608 * has changed while we are still in 609 * the loop. Although the change 610 * would not cause disaster (because 611 * it's not a deletion, but an 612 * addition,) we'd rather restart the 613 * loop just for safety. Or does this 614 * significantly reduce performance?? 615 */ 616 goto addrloop; 617 } 618 } 619 } else { 620 /* 621 * A new RA might have made a deprecated address 622 * preferred. 623 */ 624 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 625 } 626 } 627 628 /* expire prefix list */ 629 pr = nd_prefix.lh_first; 630 while (pr) { 631 /* 632 * check prefix lifetime. 633 * since pltime is just for autoconf, pltime processing for 634 * prefix is not necessary. 635 */ 636 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && 637 time_second - pr->ndpr_lastupdate > pr->ndpr_vltime) { 638 struct nd_prefix *t; 639 t = pr->ndpr_next; 640 641 /* 642 * address expiration and prefix expiration are 643 * separate. NEVER perform in6_purgeaddr here. 644 */ 645 646 prelist_remove(pr); 647 pr = t; 648 } else 649 pr = pr->ndpr_next; 650 } 651 splx(s); 652 } 653 654 static int 655 regen_tmpaddr(ia6) 656 struct in6_ifaddr *ia6; /* deprecated/invalidated temporary address */ 657 { 658 struct ifaddr *ifa; 659 struct ifnet *ifp; 660 struct in6_ifaddr *public_ifa6 = NULL; 661 662 ifp = ia6->ia_ifa.ifa_ifp; 663 for (ifa = ifp->if_addrlist.tqh_first; ifa; 664 ifa = ifa->ifa_list.tqe_next) { 665 struct in6_ifaddr *it6; 666 667 if (ifa->ifa_addr->sa_family != AF_INET6) 668 continue; 669 670 it6 = (struct in6_ifaddr *)ifa; 671 672 /* ignore no autoconf addresses. */ 673 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 674 continue; 675 676 /* ignore autoconf addresses with different prefixes. */ 677 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 678 continue; 679 680 /* 681 * Now we are looking at an autoconf address with the same 682 * prefix as ours. If the address is temporary and is still 683 * preferred, do not create another one. It would be rare, but 684 * could happen, for example, when we resume a laptop PC after 685 * a long period. 686 */ 687 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 688 !IFA6_IS_DEPRECATED(it6)) { 689 public_ifa6 = NULL; 690 break; 691 } 692 693 /* 694 * This is a public autoconf address that has the same prefix 695 * as ours. If it is preferred, keep it. We can't break the 696 * loop here, because there may be a still-preferred temporary 697 * address with the prefix. 698 */ 699 if (!IFA6_IS_DEPRECATED(it6)) 700 public_ifa6 = it6; 701 } 702 703 if (public_ifa6 != NULL) { 704 int e; 705 706 /* 707 * Random factor is introduced in the preferred lifetime, so 708 * we do not need additional delay (3rd arg to in6_tmpifadd). 709 */ 710 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 711 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 712 " tmp addr, errno=%d\n", e); 713 return (-1); 714 } 715 return (0); 716 } 717 718 return (-1); 719 } 720 721 /* 722 * Nuke neighbor cache/prefix/default router management table, right before 723 * ifp goes away. 724 */ 725 void 726 nd6_purge(ifp) 727 struct ifnet *ifp; 728 { 729 struct llinfo_nd6 *ln, *nln; 730 struct nd_defrouter *dr, *ndr; 731 struct nd_prefix *pr, *npr; 732 733 /* 734 * Nuke default router list entries toward ifp. 735 * We defer removal of default router list entries that is installed 736 * in the routing table, in order to keep additional side effects as 737 * small as possible. 738 */ 739 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 740 ndr = TAILQ_NEXT(dr, dr_entry); 741 if (dr->installed) 742 continue; 743 744 if (dr->ifp == ifp) 745 defrtrlist_del(dr); 746 } 747 for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = ndr) { 748 ndr = TAILQ_NEXT(dr, dr_entry); 749 if (!dr->installed) 750 continue; 751 752 if (dr->ifp == ifp) 753 defrtrlist_del(dr); 754 } 755 756 /* Nuke prefix list entries toward ifp */ 757 for (pr = nd_prefix.lh_first; pr; pr = npr) { 758 npr = pr->ndpr_next; 759 if (pr->ndpr_ifp == ifp) { 760 /* 761 * Because if_detach() does *not* release prefixes 762 * while purging addresses the reference count will 763 * still be above zero. We therefore reset it to 764 * make sure that the prefix really gets purged. 765 */ 766 pr->ndpr_refcnt = 0; 767 /* 768 * Previously, pr->ndpr_addr is removed as well, 769 * but I strongly believe we don't have to do it. 770 * nd6_purge() is only called from in6_ifdetach(), 771 * which removes all the associated interface addresses 772 * by itself. 773 * (jinmei@kame.net 20010129) 774 */ 775 prelist_remove(pr); 776 } 777 } 778 779 /* cancel default outgoing interface setting */ 780 if (nd6_defifindex == ifp->if_index) 781 nd6_setdefaultiface(0); 782 783 if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */ 784 /* refresh default router list */ 785 defrouter_select(); 786 } 787 788 /* 789 * Nuke neighbor cache entries for the ifp. 790 * Note that rt->rt_ifp may not be the same as ifp, 791 * due to KAME goto ours hack. See RTM_RESOLVE case in 792 * nd6_rtrequest(), and ip6_input(). 793 */ 794 ln = llinfo_nd6.ln_next; 795 while (ln && ln != &llinfo_nd6) { 796 struct rtentry *rt; 797 struct sockaddr_dl *sdl; 798 799 nln = ln->ln_next; 800 rt = ln->ln_rt; 801 if (rt && rt->rt_gateway && 802 rt->rt_gateway->sa_family == AF_LINK) { 803 sdl = (struct sockaddr_dl *)rt->rt_gateway; 804 if (sdl->sdl_index == ifp->if_index) 805 nln = nd6_free(rt, 0); 806 } 807 ln = nln; 808 } 809 } 810 811 struct rtentry * 812 nd6_lookup(addr6, create, ifp) 813 struct in6_addr *addr6; 814 int create; 815 struct ifnet *ifp; 816 { 817 struct rtentry *rt; 818 struct sockaddr_in6 sin6; 819 820 bzero(&sin6, sizeof(sin6)); 821 sin6.sin6_len = sizeof(struct sockaddr_in6); 822 sin6.sin6_family = AF_INET6; 823 sin6.sin6_addr = *addr6; 824 rt = rtalloc1((struct sockaddr *)&sin6, create); 825 if (rt && (rt->rt_flags & RTF_LLINFO) == 0) { 826 /* 827 * This is the case for the default route. 828 * If we want to create a neighbor cache for the address, we 829 * should free the route for the destination and allocate an 830 * interface route. 831 */ 832 if (create) { 833 RTFREE(rt); 834 rt = NULL; 835 } 836 } 837 if (rt == NULL) { 838 if (create && ifp) { 839 int e; 840 841 /* 842 * If no route is available and create is set, 843 * we allocate a host route for the destination 844 * and treat it like an interface route. 845 * This hack is necessary for a neighbor which can't 846 * be covered by our own prefix. 847 */ 848 struct ifaddr *ifa = 849 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp); 850 if (ifa == NULL) 851 return (NULL); 852 853 /* 854 * Create a new route. RTF_LLINFO is necessary 855 * to create a Neighbor Cache entry for the 856 * destination in nd6_rtrequest which will be 857 * called in rtrequest via ifa->ifa_rtrequest. 858 */ 859 if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6, 860 ifa->ifa_addr, (struct sockaddr *)&all1_sa, 861 (ifa->ifa_flags | RTF_HOST | RTF_LLINFO) & 862 ~RTF_CLONING, &rt)) != 0) { 863 #if 0 864 log(LOG_ERR, 865 "nd6_lookup: failed to add route for a " 866 "neighbor(%s), errno=%d\n", 867 ip6_sprintf(addr6), e); 868 #endif 869 return (NULL); 870 } 871 if (rt == NULL) 872 return (NULL); 873 if (rt->rt_llinfo) { 874 struct llinfo_nd6 *ln = 875 (struct llinfo_nd6 *)rt->rt_llinfo; 876 ln->ln_state = ND6_LLINFO_NOSTATE; 877 } 878 } else 879 return (NULL); 880 } 881 rt->rt_refcnt--; 882 /* 883 * Validation for the entry. 884 * Note that the check for rt_llinfo is necessary because a cloned 885 * route from a parent route that has the L flag (e.g. the default 886 * route to a p2p interface) may have the flag, too, while the 887 * destination is not actually a neighbor. 888 * XXX: we can't use rt->rt_ifp to check for the interface, since 889 * it might be the loopback interface if the entry is for our 890 * own address on a non-loopback interface. Instead, we should 891 * use rt->rt_ifa->ifa_ifp, which would specify the REAL 892 * interface. 893 * Note also that ifa_ifp and ifp may differ when we connect two 894 * interfaces to a same link, install a link prefix to an interface, 895 * and try to install a neighbor cache on an interface that does not 896 * have a route to the prefix. 897 */ 898 if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 || 899 rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL || 900 (ifp && rt->rt_ifa->ifa_ifp != ifp)) { 901 if (create) { 902 nd6log((LOG_DEBUG, 903 "nd6_lookup: failed to lookup %s (if = %s)\n", 904 ip6_sprintf(addr6), 905 ifp ? if_name(ifp) : "unspec")); 906 } 907 return (NULL); 908 } 909 return (rt); 910 } 911 912 /* 913 * Detect if a given IPv6 address identifies a neighbor on a given link. 914 * XXX: should take care of the destination of a p2p link? 915 */ 916 int 917 nd6_is_addr_neighbor(addr, ifp) 918 struct sockaddr_in6 *addr; 919 struct ifnet *ifp; 920 { 921 struct nd_prefix *pr; 922 923 /* 924 * A link-local address is always a neighbor. 925 * XXX: a link does not necessarily specify a single interface. 926 */ 927 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 928 struct sockaddr_in6 sin6_copy; 929 u_int32_t zone; 930 931 /* 932 * We need sin6_copy since sa6_recoverscope() may modify the 933 * content (XXX). 934 */ 935 sin6_copy = *addr; 936 if (sa6_recoverscope(&sin6_copy)) 937 return (0); /* XXX: should be impossible */ 938 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 939 return (0); 940 if (sin6_copy.sin6_scope_id == zone) 941 return (1); 942 else 943 return (0); 944 } 945 946 /* 947 * If the address matches one of our on-link prefixes, it should be a 948 * neighbor. 949 */ 950 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 951 if (pr->ndpr_ifp != ifp) 952 continue; 953 954 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) 955 continue; 956 957 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 958 &addr->sin6_addr, &pr->ndpr_mask)) 959 return (1); 960 } 961 962 /* 963 * If the default router list is empty, all addresses are regarded 964 * as on-link, and thus, as a neighbor. 965 * XXX: we restrict the condition to hosts, because routers usually do 966 * not have the "default router list". 967 */ 968 if (!ip6_forwarding && TAILQ_FIRST(&nd_defrouter) == NULL && 969 nd6_defifindex == ifp->if_index) { 970 return (1); 971 } 972 973 /* 974 * Even if the address matches none of our addresses, it might be 975 * in the neighbor cache. 976 */ 977 if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL) 978 return (1); 979 980 return (0); 981 } 982 983 /* 984 * Free an nd6 llinfo entry. 985 * Since the function would cause significant changes in the kernel, DO NOT 986 * make it global, unless you have a strong reason for the change, and are sure 987 * that the change is safe. 988 */ 989 static struct llinfo_nd6 * 990 nd6_free(rt, gc) 991 struct rtentry *rt; 992 int gc; 993 { 994 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next; 995 struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 996 struct nd_defrouter *dr; 997 998 /* 999 * we used to have pfctlinput(PRC_HOSTDEAD) here. 1000 * even though it is not harmful, it was not really necessary. 1001 */ 1002 1003 /* cancel timer */ 1004 nd6_llinfo_settimer(ln, -1); 1005 1006 if (!ip6_forwarding) { 1007 int s; 1008 s = splsoftnet(); 1009 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr, 1010 rt->rt_ifp); 1011 1012 if (dr != NULL && dr->expire && 1013 ln->ln_state == ND6_LLINFO_STALE && gc) { 1014 /* 1015 * If the reason for the deletion is just garbage 1016 * collection, and the neighbor is an active default 1017 * router, do not delete it. Instead, reset the GC 1018 * timer using the router's lifetime. 1019 * Simply deleting the entry would affect default 1020 * router selection, which is not necessarily a good 1021 * thing, especially when we're using router preference 1022 * values. 1023 * XXX: the check for ln_state would be redundant, 1024 * but we intentionally keep it just in case. 1025 */ 1026 if (dr->expire > time_second) 1027 nd6_llinfo_settimer(ln, 1028 (dr->expire - time_second) * hz); 1029 else 1030 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1031 splx(s); 1032 return (ln->ln_next); 1033 } 1034 1035 if (ln->ln_router || dr) { 1036 /* 1037 * rt6_flush must be called whether or not the neighbor 1038 * is in the Default Router List. 1039 * See a corresponding comment in nd6_na_input(). 1040 */ 1041 rt6_flush(&in6, rt->rt_ifp); 1042 } 1043 1044 if (dr) { 1045 /* 1046 * Unreachablity of a router might affect the default 1047 * router selection and on-link detection of advertised 1048 * prefixes. 1049 */ 1050 1051 /* 1052 * Temporarily fake the state to choose a new default 1053 * router and to perform on-link determination of 1054 * prefixes correctly. 1055 * Below the state will be set correctly, 1056 * or the entry itself will be deleted. 1057 */ 1058 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1059 1060 /* 1061 * Since defrouter_select() does not affect the 1062 * on-link determination and MIP6 needs the check 1063 * before the default router selection, we perform 1064 * the check now. 1065 */ 1066 pfxlist_onlink_check(); 1067 1068 /* 1069 * refresh default router list 1070 */ 1071 defrouter_select(); 1072 } 1073 splx(s); 1074 } 1075 1076 /* 1077 * Before deleting the entry, remember the next entry as the 1078 * return value. We need this because pfxlist_onlink_check() above 1079 * might have freed other entries (particularly the old next entry) as 1080 * a side effect (XXX). 1081 */ 1082 next = ln->ln_next; 1083 1084 /* 1085 * Detach the route from the routing tree and the list of neighbor 1086 * caches, and disable the route entry not to be used in already 1087 * cached routes. 1088 */ 1089 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, 1090 rt_mask(rt), 0, (struct rtentry **)0); 1091 1092 return (next); 1093 } 1094 1095 /* 1096 * Upper-layer reachability hint for Neighbor Unreachability Detection. 1097 * 1098 * XXX cost-effective methods? 1099 */ 1100 void 1101 nd6_nud_hint(rt, dst6, force) 1102 struct rtentry *rt; 1103 struct in6_addr *dst6; 1104 int force; 1105 { 1106 struct llinfo_nd6 *ln; 1107 1108 /* 1109 * If the caller specified "rt", use that. Otherwise, resolve the 1110 * routing table by supplied "dst6". 1111 */ 1112 if (rt == NULL) { 1113 if (dst6 == NULL) 1114 return; 1115 if ((rt = nd6_lookup(dst6, 0, NULL)) == NULL) 1116 return; 1117 } 1118 1119 if ((rt->rt_flags & RTF_GATEWAY) != 0 || 1120 (rt->rt_flags & RTF_LLINFO) == 0 || 1121 !rt->rt_llinfo || !rt->rt_gateway || 1122 rt->rt_gateway->sa_family != AF_LINK) { 1123 /* This is not a host route. */ 1124 return; 1125 } 1126 1127 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1128 if (ln->ln_state < ND6_LLINFO_REACHABLE) 1129 return; 1130 1131 /* 1132 * if we get upper-layer reachability confirmation many times, 1133 * it is possible we have false information. 1134 */ 1135 if (!force) { 1136 ln->ln_byhint++; 1137 if (ln->ln_byhint > nd6_maxnudhint) 1138 return; 1139 } 1140 1141 ln->ln_state = ND6_LLINFO_REACHABLE; 1142 if (!ND6_LLINFO_PERMANENT(ln)) { 1143 nd6_llinfo_settimer(ln, 1144 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 1145 } 1146 } 1147 1148 void 1149 nd6_rtrequest(req, rt, info) 1150 int req; 1151 struct rtentry *rt; 1152 struct rt_addrinfo *info; /* xxx unused */ 1153 { 1154 struct sockaddr *gate = rt->rt_gateway; 1155 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1156 static const struct sockaddr_dl null_sdl = { 1157 .sdl_len = sizeof(null_sdl), 1158 .sdl_family = AF_LINK, 1159 }; 1160 struct ifnet *ifp = rt->rt_ifp; 1161 struct ifaddr *ifa; 1162 1163 if ((rt->rt_flags & RTF_GATEWAY) != 0) 1164 return; 1165 1166 if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) { 1167 /* 1168 * This is probably an interface direct route for a link 1169 * which does not need neighbor caches (e.g. fe80::%lo0/64). 1170 * We do not need special treatment below for such a route. 1171 * Moreover, the RTF_LLINFO flag which would be set below 1172 * would annoy the ndp(8) command. 1173 */ 1174 return; 1175 } 1176 1177 if (req == RTM_RESOLVE && 1178 (nd6_need_cache(ifp) == 0 || /* stf case */ 1179 !nd6_is_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), ifp))) { 1180 /* 1181 * FreeBSD and BSD/OS often make a cloned host route based 1182 * on a less-specific route (e.g. the default route). 1183 * If the less specific route does not have a "gateway" 1184 * (this is the case when the route just goes to a p2p or an 1185 * stf interface), we'll mistakenly make a neighbor cache for 1186 * the host route, and will see strange neighbor solicitation 1187 * for the corresponding destination. In order to avoid the 1188 * confusion, we check if the destination of the route is 1189 * a neighbor in terms of neighbor discovery, and stop the 1190 * process if not. Additionally, we remove the LLINFO flag 1191 * so that ndp(8) will not try to get the neighbor information 1192 * of the destination. 1193 */ 1194 rt->rt_flags &= ~RTF_LLINFO; 1195 return; 1196 } 1197 1198 switch (req) { 1199 case RTM_ADD: 1200 /* 1201 * There is no backward compatibility :) 1202 * 1203 * if ((rt->rt_flags & RTF_HOST) == 0 && 1204 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 1205 * rt->rt_flags |= RTF_CLONING; 1206 */ 1207 if ((rt->rt_flags & RTF_CLONING) || 1208 ((rt->rt_flags & RTF_LLINFO) && !ln)) { 1209 /* 1210 * Case 1: This route should come from a route to 1211 * interface (RTF_CLONING case) or the route should be 1212 * treated as on-link but is currently not 1213 * (RTF_LLINFO && !ln case). 1214 */ 1215 rt_setgate(rt, rt_key(rt), 1216 (const struct sockaddr *)&null_sdl); 1217 gate = rt->rt_gateway; 1218 SDL(gate)->sdl_type = ifp->if_type; 1219 SDL(gate)->sdl_index = ifp->if_index; 1220 if (ln) 1221 nd6_llinfo_settimer(ln, 0); 1222 if ((rt->rt_flags & RTF_CLONING) != 0) 1223 break; 1224 } 1225 /* 1226 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here. 1227 * We don't do that here since llinfo is not ready yet. 1228 * 1229 * There are also couple of other things to be discussed: 1230 * - unsolicited NA code needs improvement beforehand 1231 * - RFC2461 says we MAY send multicast unsolicited NA 1232 * (7.2.6 paragraph 4), however, it also says that we 1233 * SHOULD provide a mechanism to prevent multicast NA storm. 1234 * we don't have anything like it right now. 1235 * note that the mechanism needs a mutual agreement 1236 * between proxies, which means that we need to implement 1237 * a new protocol, or a new kludge. 1238 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA. 1239 * we need to check ip6forwarding before sending it. 1240 * (or should we allow proxy ND configuration only for 1241 * routers? there's no mention about proxy ND from hosts) 1242 */ 1243 #if 0 1244 /* XXX it does not work */ 1245 if (rt->rt_flags & RTF_ANNOUNCE) 1246 nd6_na_output(ifp, 1247 &SIN6(rt_key(rt))->sin6_addr, 1248 &SIN6(rt_key(rt))->sin6_addr, 1249 ip6_forwarding ? ND_NA_FLAG_ROUTER : 0, 1250 1, NULL); 1251 #endif 1252 /* FALLTHROUGH */ 1253 case RTM_RESOLVE: 1254 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) { 1255 /* 1256 * Address resolution isn't necessary for a point to 1257 * point link, so we can skip this test for a p2p link. 1258 */ 1259 if (gate->sa_family != AF_LINK || 1260 gate->sa_len < sizeof(null_sdl)) { 1261 log(LOG_DEBUG, 1262 "nd6_rtrequest: bad gateway value: %s\n", 1263 if_name(ifp)); 1264 break; 1265 } 1266 SDL(gate)->sdl_type = ifp->if_type; 1267 SDL(gate)->sdl_index = ifp->if_index; 1268 } 1269 if (ln != NULL) 1270 break; /* This happens on a route change */ 1271 /* 1272 * Case 2: This route may come from cloning, or a manual route 1273 * add with a LL address. 1274 */ 1275 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln)); 1276 rt->rt_llinfo = (caddr_t)ln; 1277 if (ln == NULL) { 1278 log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n"); 1279 break; 1280 } 1281 nd6_inuse++; 1282 nd6_allocated++; 1283 bzero(ln, sizeof(*ln)); 1284 ln->ln_rt = rt; 1285 callout_init(&ln->ln_timer_ch); 1286 /* this is required for "ndp" command. - shin */ 1287 if (req == RTM_ADD) { 1288 /* 1289 * gate should have some valid AF_LINK entry, 1290 * and ln->ln_expire should have some lifetime 1291 * which is specified by ndp command. 1292 */ 1293 ln->ln_state = ND6_LLINFO_REACHABLE; 1294 ln->ln_byhint = 0; 1295 } else { 1296 /* 1297 * When req == RTM_RESOLVE, rt is created and 1298 * initialized in rtrequest(), so rt_expire is 0. 1299 */ 1300 ln->ln_state = ND6_LLINFO_NOSTATE; 1301 nd6_llinfo_settimer(ln, 0); 1302 } 1303 rt->rt_flags |= RTF_LLINFO; 1304 ln->ln_next = llinfo_nd6.ln_next; 1305 llinfo_nd6.ln_next = ln; 1306 ln->ln_prev = &llinfo_nd6; 1307 ln->ln_next->ln_prev = ln; 1308 1309 /* 1310 * check if rt_key(rt) is one of my address assigned 1311 * to the interface. 1312 */ 1313 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp, 1314 &SIN6(rt_key(rt))->sin6_addr); 1315 if (ifa) { 1316 caddr_t macp = nd6_ifptomac(ifp); 1317 nd6_llinfo_settimer(ln, -1); 1318 ln->ln_state = ND6_LLINFO_REACHABLE; 1319 ln->ln_byhint = 0; 1320 if (macp) { 1321 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen); 1322 SDL(gate)->sdl_alen = ifp->if_addrlen; 1323 } 1324 if (nd6_useloopback) { 1325 rt->rt_ifp = lo0ifp; /* XXX */ 1326 /* 1327 * Make sure rt_ifa be equal to the ifaddr 1328 * corresponding to the address. 1329 * We need this because when we refer 1330 * rt_ifa->ia6_flags in ip6_input, we assume 1331 * that the rt_ifa points to the address instead 1332 * of the loopback address. 1333 */ 1334 if (ifa != rt->rt_ifa) { 1335 IFAFREE(rt->rt_ifa); 1336 IFAREF(ifa); 1337 rt->rt_ifa = ifa; 1338 } 1339 } 1340 } else if (rt->rt_flags & RTF_ANNOUNCE) { 1341 nd6_llinfo_settimer(ln, -1); 1342 ln->ln_state = ND6_LLINFO_REACHABLE; 1343 ln->ln_byhint = 0; 1344 1345 /* join solicited node multicast for proxy ND */ 1346 if (ifp->if_flags & IFF_MULTICAST) { 1347 struct in6_addr llsol; 1348 int error; 1349 1350 llsol = SIN6(rt_key(rt))->sin6_addr; 1351 llsol.s6_addr32[0] = htonl(0xff020000); 1352 llsol.s6_addr32[1] = 0; 1353 llsol.s6_addr32[2] = htonl(1); 1354 llsol.s6_addr8[12] = 0xff; 1355 if (in6_setscope(&llsol, ifp, NULL)) 1356 break; 1357 if (!in6_addmulti(&llsol, ifp, &error, 0)) { 1358 nd6log((LOG_ERR, "%s: failed to join " 1359 "%s (errno=%d)\n", if_name(ifp), 1360 ip6_sprintf(&llsol), error)); 1361 } 1362 } 1363 } 1364 break; 1365 1366 case RTM_DELETE: 1367 if (ln == NULL) 1368 break; 1369 /* leave from solicited node multicast for proxy ND */ 1370 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 && 1371 (ifp->if_flags & IFF_MULTICAST) != 0) { 1372 struct in6_addr llsol; 1373 struct in6_multi *in6m; 1374 1375 llsol = SIN6(rt_key(rt))->sin6_addr; 1376 llsol.s6_addr32[0] = htonl(0xff020000); 1377 llsol.s6_addr32[1] = 0; 1378 llsol.s6_addr32[2] = htonl(1); 1379 llsol.s6_addr8[12] = 0xff; 1380 if (in6_setscope(&llsol, ifp, NULL) == 0) { 1381 IN6_LOOKUP_MULTI(llsol, ifp, in6m); 1382 if (in6m) 1383 in6_delmulti(in6m); 1384 } 1385 } 1386 nd6_inuse--; 1387 ln->ln_next->ln_prev = ln->ln_prev; 1388 ln->ln_prev->ln_next = ln->ln_next; 1389 ln->ln_prev = NULL; 1390 nd6_llinfo_settimer(ln, -1); 1391 rt->rt_llinfo = 0; 1392 rt->rt_flags &= ~RTF_LLINFO; 1393 clear_llinfo_pqueue(ln); 1394 Free((caddr_t)ln); 1395 } 1396 } 1397 1398 int 1399 nd6_ioctl(cmd, data, ifp) 1400 u_long cmd; 1401 caddr_t data; 1402 struct ifnet *ifp; 1403 { 1404 struct in6_drlist *drl = (struct in6_drlist *)data; 1405 struct in6_oprlist *oprl = (struct in6_oprlist *)data; 1406 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1407 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1408 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1409 struct nd_defrouter *dr; 1410 struct nd_prefix *pr; 1411 struct rtentry *rt; 1412 int i = 0, error = 0; 1413 int s; 1414 1415 switch (cmd) { 1416 case SIOCGDRLST_IN6: 1417 /* 1418 * obsolete API, use sysctl under net.inet6.icmp6 1419 */ 1420 bzero(drl, sizeof(*drl)); 1421 s = splsoftnet(); 1422 dr = TAILQ_FIRST(&nd_defrouter); 1423 while (dr && i < DRLSTSIZ) { 1424 drl->defrouter[i].rtaddr = dr->rtaddr; 1425 in6_clearscope(&drl->defrouter[i].rtaddr); 1426 1427 drl->defrouter[i].flags = dr->flags; 1428 drl->defrouter[i].rtlifetime = dr->rtlifetime; 1429 drl->defrouter[i].expire = dr->expire; 1430 drl->defrouter[i].if_index = dr->ifp->if_index; 1431 i++; 1432 dr = TAILQ_NEXT(dr, dr_entry); 1433 } 1434 splx(s); 1435 break; 1436 case SIOCGPRLST_IN6: 1437 /* 1438 * obsolete API, use sysctl under net.inet6.icmp6 1439 * 1440 * XXX the structure in6_prlist was changed in backward- 1441 * incompatible manner. in6_oprlist is used for SIOCGPRLST_IN6, 1442 * in6_prlist is used for nd6_sysctl() - fill_prlist(). 1443 */ 1444 /* 1445 * XXX meaning of fields, especialy "raflags", is very 1446 * differnet between RA prefix list and RR/static prefix list. 1447 * how about separating ioctls into two? 1448 */ 1449 bzero(oprl, sizeof(*oprl)); 1450 s = splsoftnet(); 1451 pr = nd_prefix.lh_first; 1452 while (pr && i < PRLSTSIZ) { 1453 struct nd_pfxrouter *pfr; 1454 int j; 1455 1456 oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr; 1457 oprl->prefix[i].raflags = pr->ndpr_raf; 1458 oprl->prefix[i].prefixlen = pr->ndpr_plen; 1459 oprl->prefix[i].vltime = pr->ndpr_vltime; 1460 oprl->prefix[i].pltime = pr->ndpr_pltime; 1461 oprl->prefix[i].if_index = pr->ndpr_ifp->if_index; 1462 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1463 oprl->prefix[i].expire = 0; 1464 else { 1465 time_t maxexpire; 1466 1467 /* XXX: we assume time_t is signed. */ 1468 maxexpire = (-1) & 1469 ~((time_t)1 << 1470 ((sizeof(maxexpire) * 8) - 1)); 1471 if (pr->ndpr_vltime < 1472 maxexpire - pr->ndpr_lastupdate) { 1473 oprl->prefix[i].expire = 1474 pr->ndpr_lastupdate + 1475 pr->ndpr_vltime; 1476 } else 1477 oprl->prefix[i].expire = maxexpire; 1478 } 1479 1480 pfr = pr->ndpr_advrtrs.lh_first; 1481 j = 0; 1482 while (pfr) { 1483 if (j < DRLSTSIZ) { 1484 #define RTRADDR oprl->prefix[i].advrtr[j] 1485 RTRADDR = pfr->router->rtaddr; 1486 in6_clearscope(&RTRADDR); 1487 #undef RTRADDR 1488 } 1489 j++; 1490 pfr = pfr->pfr_next; 1491 } 1492 oprl->prefix[i].advrtrs = j; 1493 oprl->prefix[i].origin = PR_ORIG_RA; 1494 1495 i++; 1496 pr = pr->ndpr_next; 1497 } 1498 splx(s); 1499 1500 break; 1501 case OSIOCGIFINFO_IN6: 1502 #define ND ndi->ndi 1503 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1504 memset(&ND, 0, sizeof(ND)); 1505 ND.linkmtu = IN6_LINKMTU(ifp); 1506 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1507 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1508 ND.reachable = ND_IFINFO(ifp)->reachable; 1509 ND.retrans = ND_IFINFO(ifp)->retrans; 1510 ND.flags = ND_IFINFO(ifp)->flags; 1511 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1512 ND.chlim = ND_IFINFO(ifp)->chlim; 1513 break; 1514 case SIOCGIFINFO_IN6: 1515 ND = *ND_IFINFO(ifp); 1516 break; 1517 case SIOCSIFINFO_IN6: 1518 /* 1519 * used to change host variables from userland. 1520 * intented for a use on router to reflect RA configurations. 1521 */ 1522 /* 0 means 'unspecified' */ 1523 if (ND.linkmtu != 0) { 1524 if (ND.linkmtu < IPV6_MMTU || 1525 ND.linkmtu > IN6_LINKMTU(ifp)) { 1526 error = EINVAL; 1527 break; 1528 } 1529 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1530 } 1531 1532 if (ND.basereachable != 0) { 1533 int obasereachable = ND_IFINFO(ifp)->basereachable; 1534 1535 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1536 if (ND.basereachable != obasereachable) 1537 ND_IFINFO(ifp)->reachable = 1538 ND_COMPUTE_RTIME(ND.basereachable); 1539 } 1540 if (ND.retrans != 0) 1541 ND_IFINFO(ifp)->retrans = ND.retrans; 1542 if (ND.chlim != 0) 1543 ND_IFINFO(ifp)->chlim = ND.chlim; 1544 /* FALLTHROUGH */ 1545 case SIOCSIFINFO_FLAGS: 1546 ND_IFINFO(ifp)->flags = ND.flags; 1547 break; 1548 #undef ND 1549 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1550 /* sync kernel routing table with the default router list */ 1551 defrouter_reset(); 1552 defrouter_select(); 1553 break; 1554 case SIOCSPFXFLUSH_IN6: 1555 { 1556 /* flush all the prefix advertised by routers */ 1557 struct nd_prefix *pfx, *next; 1558 1559 s = splsoftnet(); 1560 for (pfx = nd_prefix.lh_first; pfx; pfx = next) { 1561 struct in6_ifaddr *ia, *ia_next; 1562 1563 next = pfx->ndpr_next; 1564 1565 if (IN6_IS_ADDR_LINKLOCAL(&pfx->ndpr_prefix.sin6_addr)) 1566 continue; /* XXX */ 1567 1568 /* do we really have to remove addresses as well? */ 1569 for (ia = in6_ifaddr; ia; ia = ia_next) { 1570 /* ia might be removed. keep the next ptr. */ 1571 ia_next = ia->ia_next; 1572 1573 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1574 continue; 1575 1576 if (ia->ia6_ndpr == pfx) 1577 in6_purgeaddr(&ia->ia_ifa); 1578 } 1579 prelist_remove(pfx); 1580 } 1581 splx(s); 1582 break; 1583 } 1584 case SIOCSRTRFLUSH_IN6: 1585 { 1586 /* flush all the default routers */ 1587 struct nd_defrouter *drtr, *next; 1588 1589 s = splsoftnet(); 1590 defrouter_reset(); 1591 for (drtr = TAILQ_FIRST(&nd_defrouter); drtr; drtr = next) { 1592 next = TAILQ_NEXT(drtr, dr_entry); 1593 defrtrlist_del(drtr); 1594 } 1595 defrouter_select(); 1596 splx(s); 1597 break; 1598 } 1599 case SIOCGNBRINFO_IN6: 1600 { 1601 struct llinfo_nd6 *ln; 1602 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1603 1604 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1605 return (error); 1606 1607 s = splsoftnet(); 1608 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL || 1609 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) { 1610 error = EINVAL; 1611 splx(s); 1612 break; 1613 } 1614 nbi->state = ln->ln_state; 1615 nbi->asked = ln->ln_asked; 1616 nbi->isrouter = ln->ln_router; 1617 nbi->expire = ln->ln_expire; 1618 splx(s); 1619 1620 break; 1621 } 1622 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1623 ndif->ifindex = nd6_defifindex; 1624 break; 1625 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1626 return (nd6_setdefaultiface(ndif->ifindex)); 1627 } 1628 return (error); 1629 } 1630 1631 /* 1632 * Create neighbor cache entry and cache link-layer address, 1633 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1634 */ 1635 struct rtentry * 1636 nd6_cache_lladdr(ifp, from, lladdr, lladdrlen, type, code) 1637 struct ifnet *ifp; 1638 struct in6_addr *from; 1639 char *lladdr; 1640 int lladdrlen; 1641 int type; /* ICMP6 type */ 1642 int code; /* type dependent information */ 1643 { 1644 struct rtentry *rt = NULL; 1645 struct llinfo_nd6 *ln = NULL; 1646 int is_newentry; 1647 struct sockaddr_dl *sdl = NULL; 1648 int do_update; 1649 int olladdr; 1650 int llchange; 1651 int newstate = 0; 1652 1653 if (ifp == NULL) 1654 panic("ifp == NULL in nd6_cache_lladdr"); 1655 if (from == NULL) 1656 panic("from == NULL in nd6_cache_lladdr"); 1657 1658 /* nothing must be updated for unspecified address */ 1659 if (IN6_IS_ADDR_UNSPECIFIED(from)) 1660 return NULL; 1661 1662 /* 1663 * Validation about ifp->if_addrlen and lladdrlen must be done in 1664 * the caller. 1665 * 1666 * XXX If the link does not have link-layer adderss, what should 1667 * we do? (ifp->if_addrlen == 0) 1668 * Spec says nothing in sections for RA, RS and NA. There's small 1669 * description on it in NS section (RFC 2461 7.2.3). 1670 */ 1671 1672 rt = nd6_lookup(from, 0, ifp); 1673 if (rt == NULL) { 1674 #if 0 1675 /* nothing must be done if there's no lladdr */ 1676 if (!lladdr || !lladdrlen) 1677 return NULL; 1678 #endif 1679 1680 rt = nd6_lookup(from, 1, ifp); 1681 is_newentry = 1; 1682 } else { 1683 /* do nothing if static ndp is set */ 1684 if (rt->rt_flags & RTF_STATIC) 1685 return NULL; 1686 is_newentry = 0; 1687 } 1688 1689 if (rt == NULL) 1690 return NULL; 1691 if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) { 1692 fail: 1693 (void)nd6_free(rt, 0); 1694 return NULL; 1695 } 1696 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1697 if (ln == NULL) 1698 goto fail; 1699 if (rt->rt_gateway == NULL) 1700 goto fail; 1701 if (rt->rt_gateway->sa_family != AF_LINK) 1702 goto fail; 1703 sdl = SDL(rt->rt_gateway); 1704 1705 olladdr = (sdl->sdl_alen) ? 1 : 0; 1706 if (olladdr && lladdr) { 1707 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 1708 llchange = 1; 1709 else 1710 llchange = 0; 1711 } else 1712 llchange = 0; 1713 1714 /* 1715 * newentry olladdr lladdr llchange (*=record) 1716 * 0 n n -- (1) 1717 * 0 y n -- (2) 1718 * 0 n y -- (3) * STALE 1719 * 0 y y n (4) * 1720 * 0 y y y (5) * STALE 1721 * 1 -- n -- (6) NOSTATE(= PASSIVE) 1722 * 1 -- y -- (7) * STALE 1723 */ 1724 1725 if (lladdr) { /* (3-5) and (7) */ 1726 /* 1727 * Record source link-layer address 1728 * XXX is it dependent to ifp->if_type? 1729 */ 1730 sdl->sdl_alen = ifp->if_addrlen; 1731 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 1732 } 1733 1734 if (!is_newentry) { 1735 if ((!olladdr && lladdr) || /* (3) */ 1736 (olladdr && lladdr && llchange)) { /* (5) */ 1737 do_update = 1; 1738 newstate = ND6_LLINFO_STALE; 1739 } else /* (1-2,4) */ 1740 do_update = 0; 1741 } else { 1742 do_update = 1; 1743 if (lladdr == NULL) /* (6) */ 1744 newstate = ND6_LLINFO_NOSTATE; 1745 else /* (7) */ 1746 newstate = ND6_LLINFO_STALE; 1747 } 1748 1749 if (do_update) { 1750 /* 1751 * Update the state of the neighbor cache. 1752 */ 1753 ln->ln_state = newstate; 1754 1755 if (ln->ln_state == ND6_LLINFO_STALE) { 1756 /* 1757 * XXX: since nd6_output() below will cause 1758 * state tansition to DELAY and reset the timer, 1759 * we must set the timer now, although it is actually 1760 * meaningless. 1761 */ 1762 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1763 1764 if (ln->ln_hold) { 1765 struct mbuf *m_hold, *m_hold_next; 1766 for (m_hold = ln->ln_hold; m_hold; 1767 m_hold = m_hold_next) { 1768 struct mbuf *mpkt = NULL; 1769 1770 m_hold_next = m_hold->m_nextpkt; 1771 mpkt = m_copym(m_hold, 0, M_COPYALL, M_DONTWAIT); 1772 if (mpkt == NULL) { 1773 m_freem(m_hold); 1774 break; 1775 } 1776 mpkt->m_nextpkt = NULL; 1777 1778 /* 1779 * we assume ifp is not a p2p here, so 1780 * just set the 2nd argument as the 1781 * 1st one. 1782 */ 1783 nd6_output(ifp, ifp, mpkt, 1784 (struct sockaddr_in6 *)rt_key(rt), 1785 rt); 1786 } 1787 ln->ln_hold = NULL; 1788 } 1789 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 1790 /* probe right away */ 1791 nd6_llinfo_settimer((void *)ln, 0); 1792 } 1793 } 1794 1795 /* 1796 * ICMP6 type dependent behavior. 1797 * 1798 * NS: clear IsRouter if new entry 1799 * RS: clear IsRouter 1800 * RA: set IsRouter if there's lladdr 1801 * redir: clear IsRouter if new entry 1802 * 1803 * RA case, (1): 1804 * The spec says that we must set IsRouter in the following cases: 1805 * - If lladdr exist, set IsRouter. This means (1-5). 1806 * - If it is old entry (!newentry), set IsRouter. This means (7). 1807 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1808 * A quetion arises for (1) case. (1) case has no lladdr in the 1809 * neighbor cache, this is similar to (6). 1810 * This case is rare but we figured that we MUST NOT set IsRouter. 1811 * 1812 * newentry olladdr lladdr llchange NS RS RA redir 1813 * D R 1814 * 0 n n -- (1) c ? s 1815 * 0 y n -- (2) c s s 1816 * 0 n y -- (3) c s s 1817 * 0 y y n (4) c s s 1818 * 0 y y y (5) c s s 1819 * 1 -- n -- (6) c c c s 1820 * 1 -- y -- (7) c c s c s 1821 * 1822 * (c=clear s=set) 1823 */ 1824 switch (type & 0xff) { 1825 case ND_NEIGHBOR_SOLICIT: 1826 /* 1827 * New entry must have is_router flag cleared. 1828 */ 1829 if (is_newentry) /* (6-7) */ 1830 ln->ln_router = 0; 1831 break; 1832 case ND_REDIRECT: 1833 /* 1834 * If the icmp is a redirect to a better router, always set the 1835 * is_router flag. Otherwise, if the entry is newly created, 1836 * clear the flag. [RFC 2461, sec 8.3] 1837 */ 1838 if (code == ND_REDIRECT_ROUTER) 1839 ln->ln_router = 1; 1840 else if (is_newentry) /* (6-7) */ 1841 ln->ln_router = 0; 1842 break; 1843 case ND_ROUTER_SOLICIT: 1844 /* 1845 * is_router flag must always be cleared. 1846 */ 1847 ln->ln_router = 0; 1848 break; 1849 case ND_ROUTER_ADVERT: 1850 /* 1851 * Mark an entry with lladdr as a router. 1852 */ 1853 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */ 1854 (is_newentry && lladdr)) { /* (7) */ 1855 ln->ln_router = 1; 1856 } 1857 break; 1858 } 1859 1860 /* 1861 * When the link-layer address of a router changes, select the 1862 * best router again. In particular, when the neighbor entry is newly 1863 * created, it might affect the selection policy. 1864 * Question: can we restrict the first condition to the "is_newentry" 1865 * case? 1866 * XXX: when we hear an RA from a new router with the link-layer 1867 * address option, defrouter_select() is called twice, since 1868 * defrtrlist_update called the function as well. However, I believe 1869 * we can compromise the overhead, since it only happens the first 1870 * time. 1871 * XXX: although defrouter_select() should not have a bad effect 1872 * for those are not autoconfigured hosts, we explicitly avoid such 1873 * cases for safety. 1874 */ 1875 if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv) 1876 defrouter_select(); 1877 1878 return rt; 1879 } 1880 1881 static void 1882 nd6_slowtimo(ignored_arg) 1883 void *ignored_arg; 1884 { 1885 int s = splsoftnet(); 1886 struct nd_ifinfo *nd6if; 1887 struct ifnet *ifp; 1888 1889 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 1890 nd6_slowtimo, NULL); 1891 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1892 { 1893 nd6if = ND_IFINFO(ifp); 1894 if (nd6if->basereachable && /* already initialized */ 1895 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 1896 /* 1897 * Since reachable time rarely changes by router 1898 * advertisements, we SHOULD insure that a new random 1899 * value gets recomputed at least once every few hours. 1900 * (RFC 2461, 6.3.4) 1901 */ 1902 nd6if->recalctm = nd6_recalc_reachtm_interval; 1903 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 1904 } 1905 } 1906 splx(s); 1907 } 1908 1909 #define senderr(e) { error = (e); goto bad;} 1910 int 1911 nd6_output(ifp, origifp, m0, dst, rt0) 1912 struct ifnet *ifp; 1913 struct ifnet *origifp; 1914 struct mbuf *m0; 1915 struct sockaddr_in6 *dst; 1916 struct rtentry *rt0; 1917 { 1918 struct mbuf *m = m0; 1919 struct rtentry *rt = rt0; 1920 struct sockaddr_in6 *gw6 = NULL; 1921 struct llinfo_nd6 *ln = NULL; 1922 int error = 0; 1923 1924 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr)) 1925 goto sendpkt; 1926 1927 if (nd6_need_cache(ifp) == 0) 1928 goto sendpkt; 1929 1930 /* 1931 * next hop determination. This routine is derived from ether_output. 1932 */ 1933 if (rt) { 1934 if ((rt->rt_flags & RTF_UP) == 0) { 1935 if ((rt0 = rt = rtalloc1((struct sockaddr *)dst, 1936 1)) != NULL) 1937 { 1938 rt->rt_refcnt--; 1939 if (rt->rt_ifp != ifp) 1940 senderr(EHOSTUNREACH); 1941 } else 1942 senderr(EHOSTUNREACH); 1943 } 1944 1945 if (rt->rt_flags & RTF_GATEWAY) { 1946 gw6 = (struct sockaddr_in6 *)rt->rt_gateway; 1947 1948 /* 1949 * We skip link-layer address resolution and NUD 1950 * if the gateway is not a neighbor from ND point 1951 * of view, regardless of the value of nd_ifinfo.flags. 1952 * The second condition is a bit tricky; we skip 1953 * if the gateway is our own address, which is 1954 * sometimes used to install a route to a p2p link. 1955 */ 1956 if (!nd6_is_addr_neighbor(gw6, ifp) || 1957 in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) { 1958 /* 1959 * We allow this kind of tricky route only 1960 * when the outgoing interface is p2p. 1961 * XXX: we may need a more generic rule here. 1962 */ 1963 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 1964 senderr(EHOSTUNREACH); 1965 1966 goto sendpkt; 1967 } 1968 1969 if (rt->rt_gwroute == 0) 1970 goto lookup; 1971 if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) { 1972 rtfree(rt); rt = rt0; 1973 lookup: 1974 rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1); 1975 if ((rt = rt->rt_gwroute) == 0) 1976 senderr(EHOSTUNREACH); 1977 /* the "G" test below also prevents rt == rt0 */ 1978 if ((rt->rt_flags & RTF_GATEWAY) || 1979 (rt->rt_ifp != ifp)) { 1980 rt->rt_refcnt--; 1981 rt0->rt_gwroute = 0; 1982 senderr(EHOSTUNREACH); 1983 } 1984 } 1985 } 1986 } 1987 1988 /* 1989 * Address resolution or Neighbor Unreachability Detection 1990 * for the next hop. 1991 * At this point, the destination of the packet must be a unicast 1992 * or an anycast address(i.e. not a multicast). 1993 */ 1994 1995 /* Look up the neighbor cache for the nexthop */ 1996 if (rt && (rt->rt_flags & RTF_LLINFO) != 0) 1997 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1998 else { 1999 /* 2000 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 2001 * the condition below is not very efficient. But we believe 2002 * it is tolerable, because this should be a rare case. 2003 */ 2004 if (nd6_is_addr_neighbor(dst, ifp) && 2005 (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL) 2006 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2007 } 2008 if (ln == NULL || rt == NULL) { 2009 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 && 2010 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { 2011 log(LOG_DEBUG, 2012 "nd6_output: can't allocate llinfo for %s " 2013 "(ln=%p, rt=%p)\n", 2014 ip6_sprintf(&dst->sin6_addr), ln, rt); 2015 senderr(EIO); /* XXX: good error? */ 2016 } 2017 2018 goto sendpkt; /* send anyway */ 2019 } 2020 2021 /* We don't have to do link-layer address resolution on a p2p link. */ 2022 if ((ifp->if_flags & IFF_POINTOPOINT) != 0 && 2023 ln->ln_state < ND6_LLINFO_REACHABLE) { 2024 ln->ln_state = ND6_LLINFO_STALE; 2025 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 2026 } 2027 2028 /* 2029 * The first time we send a packet to a neighbor whose entry is 2030 * STALE, we have to change the state to DELAY and a sets a timer to 2031 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2032 * neighbor unreachability detection on expiration. 2033 * (RFC 2461 7.3.3) 2034 */ 2035 if (ln->ln_state == ND6_LLINFO_STALE) { 2036 ln->ln_asked = 0; 2037 ln->ln_state = ND6_LLINFO_DELAY; 2038 nd6_llinfo_settimer(ln, (long)nd6_delay * hz); 2039 } 2040 2041 /* 2042 * If the neighbor cache entry has a state other than INCOMPLETE 2043 * (i.e. its link-layer address is already resolved), just 2044 * send the packet. 2045 */ 2046 if (ln->ln_state > ND6_LLINFO_INCOMPLETE) 2047 goto sendpkt; 2048 2049 /* 2050 * There is a neighbor cache entry, but no ethernet address 2051 * response yet. Append this latest packet to the end of the 2052 * packet queue in the mbuf, unless the number of the packet 2053 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, 2054 * the oldest packet in the queue will be removed. 2055 */ 2056 if (ln->ln_state == ND6_LLINFO_NOSTATE) 2057 ln->ln_state = ND6_LLINFO_INCOMPLETE; 2058 if (ln->ln_hold) { 2059 struct mbuf *m_hold; 2060 int i; 2061 2062 i = 0; 2063 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold->m_nextpkt) { 2064 i++; 2065 if (m_hold->m_nextpkt == NULL) { 2066 m_hold->m_nextpkt = m; 2067 break; 2068 } 2069 } 2070 while (i >= nd6_maxqueuelen) { 2071 m_hold = ln->ln_hold; 2072 ln->ln_hold = ln->ln_hold->m_nextpkt; 2073 m_freem(m_hold); 2074 i--; 2075 } 2076 } else { 2077 ln->ln_hold = m; 2078 } 2079 2080 /* 2081 * If there has been no NS for the neighbor after entering the 2082 * INCOMPLETE state, send the first solicitation. 2083 */ 2084 if (!ND6_LLINFO_PERMANENT(ln) && ln->ln_asked == 0) { 2085 ln->ln_asked++; 2086 nd6_llinfo_settimer(ln, 2087 (long)ND_IFINFO(ifp)->retrans * hz / 1000); 2088 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 2089 } 2090 return (0); 2091 2092 sendpkt: 2093 /* discard the packet if IPv6 operation is disabled on the interface */ 2094 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 2095 error = ENETDOWN; /* better error? */ 2096 goto bad; 2097 } 2098 2099 #ifdef IPSEC 2100 /* clean ipsec history once it goes out of the node */ 2101 ipsec_delaux(m); 2102 #endif 2103 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 2104 return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst, 2105 rt)); 2106 } 2107 return ((*ifp->if_output)(ifp, m, (struct sockaddr *)dst, rt)); 2108 2109 bad: 2110 if (m) 2111 m_freem(m); 2112 return (error); 2113 } 2114 #undef senderr 2115 2116 int 2117 nd6_need_cache(ifp) 2118 struct ifnet *ifp; 2119 { 2120 /* 2121 * XXX: we currently do not make neighbor cache on any interface 2122 * other than ARCnet, Ethernet, FDDI and GIF. 2123 * 2124 * RFC2893 says: 2125 * - unidirectional tunnels needs no ND 2126 */ 2127 switch (ifp->if_type) { 2128 case IFT_ARCNET: 2129 case IFT_ETHER: 2130 case IFT_FDDI: 2131 case IFT_IEEE1394: 2132 case IFT_CARP: 2133 case IFT_GIF: /* XXX need more cases? */ 2134 case IFT_PPP: 2135 case IFT_TUNNEL: 2136 return (1); 2137 default: 2138 return (0); 2139 } 2140 } 2141 2142 int 2143 nd6_storelladdr(ifp, rt, m, dst, desten) 2144 struct ifnet *ifp; 2145 struct rtentry *rt; 2146 struct mbuf *m; 2147 struct sockaddr *dst; 2148 u_char *desten; 2149 { 2150 struct sockaddr_dl *sdl; 2151 2152 if (m->m_flags & M_MCAST) { 2153 switch (ifp->if_type) { 2154 case IFT_ETHER: 2155 case IFT_FDDI: 2156 ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr, 2157 desten); 2158 return (1); 2159 case IFT_IEEE1394: 2160 bcopy(ifp->if_broadcastaddr, desten, ifp->if_addrlen); 2161 return (1); 2162 case IFT_ARCNET: 2163 *desten = 0; 2164 return (1); 2165 default: 2166 m_freem(m); 2167 return (0); 2168 } 2169 } 2170 2171 if (rt == NULL) { 2172 /* this could happen, if we could not allocate memory */ 2173 m_freem(m); 2174 return (0); 2175 } 2176 if (rt->rt_gateway->sa_family != AF_LINK) { 2177 printf("nd6_storelladdr: something odd happens\n"); 2178 m_freem(m); 2179 return (0); 2180 } 2181 sdl = SDL(rt->rt_gateway); 2182 if (sdl->sdl_alen == 0) { 2183 /* this should be impossible, but we bark here for debugging */ 2184 printf("nd6_storelladdr: sdl_alen == 0, dst=%s, if=%s\n", 2185 ip6_sprintf(&SIN6(dst)->sin6_addr), if_name(ifp)); 2186 m_freem(m); 2187 return (0); 2188 } 2189 2190 bcopy(LLADDR(sdl), desten, sdl->sdl_alen); 2191 return (1); 2192 } 2193 2194 static void 2195 clear_llinfo_pqueue(ln) 2196 struct llinfo_nd6 *ln; 2197 { 2198 struct mbuf *m_hold, *m_hold_next; 2199 2200 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold_next) { 2201 m_hold_next = m_hold->m_nextpkt; 2202 m_hold->m_nextpkt = NULL; 2203 m_freem(m_hold); 2204 } 2205 2206 ln->ln_hold = NULL; 2207 return; 2208 } 2209 2210 int 2211 nd6_sysctl(name, oldp, oldlenp, newp, newlen) 2212 int name; 2213 void *oldp; /* syscall arg, need copyout */ 2214 size_t *oldlenp; 2215 void *newp; /* syscall arg, need copyin */ 2216 size_t newlen; 2217 { 2218 void *p; 2219 size_t ol; 2220 int error; 2221 2222 error = 0; 2223 2224 if (newp) 2225 return EPERM; 2226 if (oldp && !oldlenp) 2227 return EINVAL; 2228 ol = oldlenp ? *oldlenp : 0; 2229 2230 if (oldp) { 2231 p = malloc(*oldlenp, M_TEMP, M_WAITOK); 2232 if (p == NULL) 2233 return ENOMEM; 2234 } else 2235 p = NULL; 2236 switch (name) { 2237 case ICMPV6CTL_ND6_DRLIST: 2238 error = fill_drlist(p, oldlenp, ol); 2239 if (!error && p != NULL && oldp != NULL) 2240 error = copyout(p, oldp, *oldlenp); 2241 break; 2242 2243 case ICMPV6CTL_ND6_PRLIST: 2244 error = fill_prlist(p, oldlenp, ol); 2245 if (!error && p != NULL && oldp != NULL) 2246 error = copyout(p, oldp, *oldlenp); 2247 break; 2248 2249 case ICMPV6CTL_ND6_MAXQLEN: 2250 break; 2251 2252 default: 2253 error = ENOPROTOOPT; 2254 break; 2255 } 2256 if (p) 2257 free(p, M_TEMP); 2258 2259 return (error); 2260 } 2261 2262 static int 2263 fill_drlist(oldp, oldlenp, ol) 2264 void *oldp; 2265 size_t *oldlenp, ol; 2266 { 2267 int error = 0, s; 2268 struct in6_defrouter *d = NULL, *de = NULL; 2269 struct nd_defrouter *dr; 2270 size_t l; 2271 2272 s = splsoftnet(); 2273 2274 if (oldp) { 2275 d = (struct in6_defrouter *)oldp; 2276 de = (struct in6_defrouter *)((caddr_t)oldp + *oldlenp); 2277 } 2278 l = 0; 2279 2280 for (dr = TAILQ_FIRST(&nd_defrouter); dr; 2281 dr = TAILQ_NEXT(dr, dr_entry)) { 2282 2283 if (oldp && d + 1 <= de) { 2284 bzero(d, sizeof(*d)); 2285 d->rtaddr.sin6_family = AF_INET6; 2286 d->rtaddr.sin6_len = sizeof(struct sockaddr_in6); 2287 d->rtaddr.sin6_addr = dr->rtaddr; 2288 if (sa6_recoverscope(&d->rtaddr)) { 2289 log(LOG_ERR, 2290 "scope error in router list (%s)\n", 2291 ip6_sprintf(&d->rtaddr.sin6_addr)); 2292 /* XXX: press on... */ 2293 } 2294 d->flags = dr->flags; 2295 d->rtlifetime = dr->rtlifetime; 2296 d->expire = dr->expire; 2297 d->if_index = dr->ifp->if_index; 2298 } 2299 2300 l += sizeof(*d); 2301 if (d) 2302 d++; 2303 } 2304 2305 if (oldp) { 2306 if (l > ol) 2307 error = ENOMEM; 2308 } 2309 if (oldlenp) 2310 *oldlenp = l; /* (caddr_t)d - (caddr_t)oldp */ 2311 2312 splx(s); 2313 2314 return (error); 2315 } 2316 2317 static int 2318 fill_prlist(oldp, oldlenp, ol) 2319 void *oldp; 2320 size_t *oldlenp, ol; 2321 { 2322 int error = 0, s; 2323 struct nd_prefix *pr; 2324 struct in6_prefix *p = NULL; 2325 struct in6_prefix *pe = NULL; 2326 size_t l; 2327 2328 s = splsoftnet(); 2329 2330 if (oldp) { 2331 p = (struct in6_prefix *)oldp; 2332 pe = (struct in6_prefix *)((caddr_t)oldp + *oldlenp); 2333 } 2334 l = 0; 2335 2336 for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 2337 u_short advrtrs; 2338 size_t advance; 2339 struct sockaddr_in6 *sin6; 2340 struct sockaddr_in6 *s6; 2341 struct nd_pfxrouter *pfr; 2342 2343 if (oldp && p + 1 <= pe) 2344 { 2345 bzero(p, sizeof(*p)); 2346 sin6 = (struct sockaddr_in6 *)(p + 1); 2347 2348 p->prefix = pr->ndpr_prefix; 2349 if (sa6_recoverscope(&p->prefix)) { 2350 log(LOG_ERR, 2351 "scope error in prefix list (%s)\n", 2352 ip6_sprintf(&p->prefix.sin6_addr)); 2353 /* XXX: press on... */ 2354 } 2355 p->raflags = pr->ndpr_raf; 2356 p->prefixlen = pr->ndpr_plen; 2357 p->vltime = pr->ndpr_vltime; 2358 p->pltime = pr->ndpr_pltime; 2359 p->if_index = pr->ndpr_ifp->if_index; 2360 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2361 p->expire = 0; 2362 else { 2363 time_t maxexpire; 2364 2365 /* XXX: we assume time_t is signed. */ 2366 maxexpire = (-1) & 2367 ~((time_t)1 << 2368 ((sizeof(maxexpire) * 8) - 1)); 2369 if (pr->ndpr_vltime < 2370 maxexpire - pr->ndpr_lastupdate) { 2371 p->expire = pr->ndpr_lastupdate + 2372 pr->ndpr_vltime; 2373 } else 2374 p->expire = maxexpire; 2375 } 2376 p->refcnt = pr->ndpr_refcnt; 2377 p->flags = pr->ndpr_stateflags; 2378 p->origin = PR_ORIG_RA; 2379 advrtrs = 0; 2380 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2381 pfr = pfr->pfr_next) { 2382 if ((void *)&sin6[advrtrs + 1] > (void *)pe) { 2383 advrtrs++; 2384 continue; 2385 } 2386 s6 = &sin6[advrtrs]; 2387 s6->sin6_family = AF_INET6; 2388 s6->sin6_len = sizeof(struct sockaddr_in6); 2389 s6->sin6_addr = pfr->router->rtaddr; 2390 s6->sin6_scope_id = 0; 2391 if (sa6_recoverscope(s6)) { 2392 log(LOG_ERR, 2393 "scope error in " 2394 "prefix list (%s)\n", 2395 ip6_sprintf(&pfr->router->rtaddr)); 2396 } 2397 advrtrs++; 2398 } 2399 p->advrtrs = advrtrs; 2400 } 2401 else { 2402 advrtrs = 0; 2403 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2404 pfr = pfr->pfr_next) 2405 advrtrs++; 2406 } 2407 2408 advance = sizeof(*p) + sizeof(*sin6) * advrtrs; 2409 l += advance; 2410 if (p) 2411 p = (struct in6_prefix *)((caddr_t)p + advance); 2412 } 2413 2414 if (oldp) { 2415 *oldlenp = l; /* (caddr_t)d - (caddr_t)oldp */ 2416 if (l > ol) 2417 error = ENOMEM; 2418 } else 2419 *oldlenp = l; 2420 2421 splx(s); 2422 2423 return (error); 2424 } 2425