1 /* $NetBSD: nd6.c,v 1.131 2008/11/07 00:20:18 dyoung 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 1.131 2008/11/07 00:20:18 dyoung 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/socketvar.h> 45 #include <sys/sockio.h> 46 #include <sys/time.h> 47 #include <sys/kernel.h> 48 #include <sys/protosw.h> 49 #include <sys/errno.h> 50 #include <sys/ioctl.h> 51 #include <sys/syslog.h> 52 #include <sys/queue.h> 53 54 #include <net/if.h> 55 #include <net/if_dl.h> 56 #include <net/if_types.h> 57 #include <net/route.h> 58 #include <net/if_ether.h> 59 #include <net/if_fddi.h> 60 #include <net/if_arc.h> 61 62 #include <netinet/in.h> 63 #include <netinet6/in6_var.h> 64 #include <netinet/ip6.h> 65 #include <netinet6/ip6_var.h> 66 #include <netinet6/scope6_var.h> 67 #include <netinet6/nd6.h> 68 #include <netinet/icmp6.h> 69 #include <netinet6/icmp6_private.h> 70 71 #ifdef IPSEC 72 #include <netinet6/ipsec.h> 73 #endif 74 75 #include <net/net_osdep.h> 76 77 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ 78 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ 79 80 /* timer values */ 81 int nd6_prune = 1; /* walk list every 1 seconds */ 82 int nd6_delay = 5; /* delay first probe time 5 second */ 83 int nd6_umaxtries = 3; /* maximum unicast query */ 84 int nd6_mmaxtries = 3; /* maximum multicast query */ 85 int nd6_useloopback = 1; /* use loopback interface for local traffic */ 86 int nd6_gctimer = (60 * 60 * 24); /* 1 day: garbage collection timer */ 87 88 /* preventing too many loops in ND option parsing */ 89 int nd6_maxndopt = 10; /* max # of ND options allowed */ 90 91 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */ 92 93 int nd6_maxqueuelen = 1; /* max # of packets cached in unresolved ND entries */ 94 95 #ifdef ND6_DEBUG 96 int nd6_debug = 1; 97 #else 98 int nd6_debug = 0; 99 #endif 100 101 /* for debugging? */ 102 static int nd6_inuse, nd6_allocated; 103 104 struct llinfo_nd6 llinfo_nd6 = { 105 .ln_prev = &llinfo_nd6, 106 .ln_next = &llinfo_nd6, 107 }; 108 struct nd_drhead nd_defrouter; 109 struct nd_prhead nd_prefix = { 0 }; 110 111 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL; 112 static const struct sockaddr_in6 all1_sa = { 113 .sin6_family = AF_INET6 114 , .sin6_len = sizeof(struct sockaddr_in6) 115 , .sin6_addr = {.s6_addr = {0xff, 0xff, 0xff, 0xff, 116 0xff, 0xff, 0xff, 0xff, 117 0xff, 0xff, 0xff, 0xff, 118 0xff, 0xff, 0xff, 0xff}} 119 }; 120 121 static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *); 122 static void nd6_slowtimo(void *); 123 static int regen_tmpaddr(struct in6_ifaddr *); 124 static struct llinfo_nd6 *nd6_free(struct rtentry *, int); 125 static void nd6_llinfo_timer(void *); 126 static void clear_llinfo_pqueue(struct llinfo_nd6 *); 127 128 callout_t nd6_slowtimo_ch; 129 callout_t nd6_timer_ch; 130 extern callout_t in6_tmpaddrtimer_ch; 131 132 static int fill_drlist(void *, size_t *, size_t); 133 static int fill_prlist(void *, size_t *, size_t); 134 135 MALLOC_DEFINE(M_IP6NDP, "NDP", "IPv6 Neighbour Discovery"); 136 137 void 138 nd6_init(void) 139 { 140 static int nd6_init_done = 0; 141 142 if (nd6_init_done) { 143 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n"); 144 return; 145 } 146 147 /* initialization of the default router list */ 148 TAILQ_INIT(&nd_defrouter); 149 150 nd6_init_done = 1; 151 152 callout_init(&nd6_slowtimo_ch, CALLOUT_MPSAFE); 153 callout_init(&nd6_timer_ch, CALLOUT_MPSAFE); 154 155 /* start timer */ 156 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 157 nd6_slowtimo, NULL); 158 } 159 160 struct nd_ifinfo * 161 nd6_ifattach(struct ifnet *ifp) 162 { 163 struct nd_ifinfo *nd; 164 165 nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK); 166 memset(nd, 0, sizeof(*nd)); 167 168 nd->initialized = 1; 169 170 nd->chlim = IPV6_DEFHLIM; 171 nd->basereachable = REACHABLE_TIME; 172 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 173 nd->retrans = RETRANS_TIMER; 174 /* 175 * Note that the default value of ip6_accept_rtadv is 0, which means 176 * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV 177 * here. 178 */ 179 nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV); 180 181 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 182 nd6_setmtu0(ifp, nd); 183 184 return nd; 185 } 186 187 void 188 nd6_ifdetach(struct nd_ifinfo *nd) 189 { 190 191 free(nd, M_IP6NDP); 192 } 193 194 void 195 nd6_setmtu(struct ifnet *ifp) 196 { 197 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 198 } 199 200 void 201 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi) 202 { 203 u_int32_t omaxmtu; 204 205 omaxmtu = ndi->maxmtu; 206 207 switch (ifp->if_type) { 208 case IFT_ARCNET: 209 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */ 210 break; 211 case IFT_FDDI: 212 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); 213 break; 214 default: 215 ndi->maxmtu = ifp->if_mtu; 216 break; 217 } 218 219 /* 220 * Decreasing the interface MTU under IPV6 minimum MTU may cause 221 * undesirable situation. We thus notify the operator of the change 222 * explicitly. The check for omaxmtu is necessary to restrict the 223 * log to the case of changing the MTU, not initializing it. 224 */ 225 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 226 log(LOG_NOTICE, "nd6_setmtu0: new link MTU on %s (%lu) is too" 227 " small for IPv6 which needs %lu\n", 228 if_name(ifp), (unsigned long)ndi->maxmtu, (unsigned long) 229 IPV6_MMTU); 230 } 231 232 if (ndi->maxmtu > in6_maxmtu) 233 in6_setmaxmtu(); /* check all interfaces just in case */ 234 } 235 236 void 237 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts) 238 { 239 240 memset(ndopts, 0, sizeof(*ndopts)); 241 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 242 ndopts->nd_opts_last 243 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 244 245 if (icmp6len == 0) { 246 ndopts->nd_opts_done = 1; 247 ndopts->nd_opts_search = NULL; 248 } 249 } 250 251 /* 252 * Take one ND option. 253 */ 254 struct nd_opt_hdr * 255 nd6_option(union nd_opts *ndopts) 256 { 257 struct nd_opt_hdr *nd_opt; 258 int olen; 259 260 if (ndopts == NULL) 261 panic("ndopts == NULL in nd6_option"); 262 if (ndopts->nd_opts_last == NULL) 263 panic("uninitialized ndopts in nd6_option"); 264 if (ndopts->nd_opts_search == NULL) 265 return NULL; 266 if (ndopts->nd_opts_done) 267 return NULL; 268 269 nd_opt = ndopts->nd_opts_search; 270 271 /* make sure nd_opt_len is inside the buffer */ 272 if ((void *)&nd_opt->nd_opt_len >= (void *)ndopts->nd_opts_last) { 273 memset(ndopts, 0, sizeof(*ndopts)); 274 return NULL; 275 } 276 277 olen = nd_opt->nd_opt_len << 3; 278 if (olen == 0) { 279 /* 280 * Message validation requires that all included 281 * options have a length that is greater than zero. 282 */ 283 memset(ndopts, 0, sizeof(*ndopts)); 284 return NULL; 285 } 286 287 ndopts->nd_opts_search = (struct nd_opt_hdr *)((char *)nd_opt + olen); 288 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 289 /* option overruns the end of buffer, invalid */ 290 memset(ndopts, 0, sizeof(*ndopts)); 291 return NULL; 292 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 293 /* reached the end of options chain */ 294 ndopts->nd_opts_done = 1; 295 ndopts->nd_opts_search = NULL; 296 } 297 return nd_opt; 298 } 299 300 /* 301 * Parse multiple ND options. 302 * This function is much easier to use, for ND routines that do not need 303 * multiple options of the same type. 304 */ 305 int 306 nd6_options(union nd_opts *ndopts) 307 { 308 struct nd_opt_hdr *nd_opt; 309 int i = 0; 310 311 if (ndopts == NULL) 312 panic("ndopts == NULL in nd6_options"); 313 if (ndopts->nd_opts_last == NULL) 314 panic("uninitialized ndopts in nd6_options"); 315 if (ndopts->nd_opts_search == NULL) 316 return 0; 317 318 while (1) { 319 nd_opt = nd6_option(ndopts); 320 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 321 /* 322 * Message validation requires that all included 323 * options have a length that is greater than zero. 324 */ 325 ICMP6_STATINC(ICMP6_STAT_ND_BADOPT); 326 memset(ndopts, 0, sizeof(*ndopts)); 327 return -1; 328 } 329 330 if (nd_opt == NULL) 331 goto skip1; 332 333 switch (nd_opt->nd_opt_type) { 334 case ND_OPT_SOURCE_LINKADDR: 335 case ND_OPT_TARGET_LINKADDR: 336 case ND_OPT_MTU: 337 case ND_OPT_REDIRECTED_HEADER: 338 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 339 nd6log((LOG_INFO, 340 "duplicated ND6 option found (type=%d)\n", 341 nd_opt->nd_opt_type)); 342 /* XXX bark? */ 343 } else { 344 ndopts->nd_opt_array[nd_opt->nd_opt_type] 345 = nd_opt; 346 } 347 break; 348 case ND_OPT_PREFIX_INFORMATION: 349 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 350 ndopts->nd_opt_array[nd_opt->nd_opt_type] 351 = nd_opt; 352 } 353 ndopts->nd_opts_pi_end = 354 (struct nd_opt_prefix_info *)nd_opt; 355 break; 356 default: 357 /* 358 * Unknown options must be silently ignored, 359 * to accommodate future extension to the protocol. 360 */ 361 nd6log((LOG_DEBUG, 362 "nd6_options: unsupported option %d - " 363 "option ignored\n", nd_opt->nd_opt_type)); 364 } 365 366 skip1: 367 i++; 368 if (i > nd6_maxndopt) { 369 ICMP6_STATINC(ICMP6_STAT_ND_TOOMANYOPT); 370 nd6log((LOG_INFO, "too many loop in nd opt\n")); 371 break; 372 } 373 374 if (ndopts->nd_opts_done) 375 break; 376 } 377 378 return 0; 379 } 380 381 /* 382 * ND6 timer routine to handle ND6 entries 383 */ 384 void 385 nd6_llinfo_settimer(struct llinfo_nd6 *ln, long xtick) 386 { 387 int s; 388 389 s = splsoftnet(); 390 391 if (xtick < 0) { 392 ln->ln_expire = 0; 393 ln->ln_ntick = 0; 394 callout_stop(&ln->ln_timer_ch); 395 } else { 396 ln->ln_expire = time_second + xtick / hz; 397 if (xtick > INT_MAX) { 398 ln->ln_ntick = xtick - INT_MAX; 399 callout_reset(&ln->ln_timer_ch, INT_MAX, 400 nd6_llinfo_timer, ln); 401 } else { 402 ln->ln_ntick = 0; 403 callout_reset(&ln->ln_timer_ch, xtick, 404 nd6_llinfo_timer, ln); 405 } 406 } 407 408 splx(s); 409 } 410 411 static void 412 nd6_llinfo_timer(void *arg) 413 { 414 struct llinfo_nd6 *ln; 415 struct rtentry *rt; 416 const struct sockaddr_in6 *dst; 417 struct ifnet *ifp; 418 struct nd_ifinfo *ndi = NULL; 419 420 mutex_enter(softnet_lock); 421 KERNEL_LOCK(1, NULL); 422 423 ln = (struct llinfo_nd6 *)arg; 424 425 if (ln->ln_ntick > 0) { 426 nd6_llinfo_settimer(ln, ln->ln_ntick); 427 KERNEL_UNLOCK_ONE(NULL); 428 mutex_exit(softnet_lock); 429 return; 430 } 431 432 if ((rt = ln->ln_rt) == NULL) 433 panic("ln->ln_rt == NULL"); 434 if ((ifp = rt->rt_ifp) == NULL) 435 panic("ln->ln_rt->rt_ifp == NULL"); 436 ndi = ND_IFINFO(ifp); 437 dst = satocsin6(rt_getkey(rt)); 438 439 /* sanity check */ 440 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln) 441 panic("rt_llinfo(%p) is not equal to ln(%p)", 442 rt->rt_llinfo, ln); 443 if (!dst) 444 panic("dst=0 in nd6_timer(ln=%p)", ln); 445 446 switch (ln->ln_state) { 447 case ND6_LLINFO_INCOMPLETE: 448 if (ln->ln_asked < nd6_mmaxtries) { 449 ln->ln_asked++; 450 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 451 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 452 } else { 453 struct mbuf *m = ln->ln_hold; 454 if (m) { 455 struct mbuf *m0; 456 457 /* 458 * assuming every packet in ln_hold has 459 * the same IP header 460 */ 461 m0 = m->m_nextpkt; 462 m->m_nextpkt = NULL; 463 icmp6_error2(m, ICMP6_DST_UNREACH, 464 ICMP6_DST_UNREACH_ADDR, 0, rt->rt_ifp); 465 466 ln->ln_hold = m0; 467 clear_llinfo_pqueue(ln); 468 } 469 (void)nd6_free(rt, 0); 470 ln = NULL; 471 } 472 break; 473 case ND6_LLINFO_REACHABLE: 474 if (!ND6_LLINFO_PERMANENT(ln)) { 475 ln->ln_state = ND6_LLINFO_STALE; 476 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 477 } 478 break; 479 480 case ND6_LLINFO_STALE: 481 /* Garbage Collection(RFC 2461 5.3) */ 482 if (!ND6_LLINFO_PERMANENT(ln)) { 483 (void)nd6_free(rt, 1); 484 ln = NULL; 485 } 486 break; 487 488 case ND6_LLINFO_DELAY: 489 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 490 /* We need NUD */ 491 ln->ln_asked = 1; 492 ln->ln_state = ND6_LLINFO_PROBE; 493 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 494 nd6_ns_output(ifp, &dst->sin6_addr, 495 &dst->sin6_addr, ln, 0); 496 } else { 497 ln->ln_state = ND6_LLINFO_STALE; /* XXX */ 498 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 499 } 500 break; 501 case ND6_LLINFO_PROBE: 502 if (ln->ln_asked < nd6_umaxtries) { 503 ln->ln_asked++; 504 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 505 nd6_ns_output(ifp, &dst->sin6_addr, 506 &dst->sin6_addr, ln, 0); 507 } else { 508 (void)nd6_free(rt, 0); 509 ln = NULL; 510 } 511 break; 512 } 513 514 KERNEL_UNLOCK_ONE(NULL); 515 mutex_exit(softnet_lock); 516 } 517 518 /* 519 * ND6 timer routine to expire default route list and prefix list 520 */ 521 void 522 nd6_timer(void *ignored_arg) 523 { 524 struct nd_defrouter *next_dr, *dr; 525 struct nd_prefix *next_pr, *pr; 526 struct in6_ifaddr *ia6, *nia6; 527 struct in6_addrlifetime *lt6; 528 529 callout_reset(&nd6_timer_ch, nd6_prune * hz, 530 nd6_timer, NULL); 531 532 mutex_enter(softnet_lock); 533 KERNEL_LOCK(1, NULL); 534 535 /* expire default router list */ 536 537 for (dr = TAILQ_FIRST(&nd_defrouter); dr != NULL; dr = next_dr) { 538 next_dr = TAILQ_NEXT(dr, dr_entry); 539 if (dr->expire && dr->expire < time_second) { 540 defrtrlist_del(dr); 541 } 542 } 543 544 /* 545 * expire interface addresses. 546 * in the past the loop was inside prefix expiry processing. 547 * However, from a stricter speci-confrmance standpoint, we should 548 * rather separate address lifetimes and prefix lifetimes. 549 */ 550 addrloop: 551 for (ia6 = in6_ifaddr; ia6; ia6 = nia6) { 552 nia6 = ia6->ia_next; 553 /* check address lifetime */ 554 lt6 = &ia6->ia6_lifetime; 555 if (IFA6_IS_INVALID(ia6)) { 556 int regen = 0; 557 558 /* 559 * If the expiring address is temporary, try 560 * regenerating a new one. This would be useful when 561 * we suspended a laptop PC, then turned it on after a 562 * period that could invalidate all temporary 563 * addresses. Although we may have to restart the 564 * loop (see below), it must be after purging the 565 * address. Otherwise, we'd see an infinite loop of 566 * regeneration. 567 */ 568 if (ip6_use_tempaddr && 569 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 570 if (regen_tmpaddr(ia6) == 0) 571 regen = 1; 572 } 573 574 in6_purgeaddr(&ia6->ia_ifa); 575 576 if (regen) 577 goto addrloop; /* XXX: see below */ 578 } else if (IFA6_IS_DEPRECATED(ia6)) { 579 int oldflags = ia6->ia6_flags; 580 581 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 582 583 /* 584 * If a temporary address has just become deprecated, 585 * regenerate a new one if possible. 586 */ 587 if (ip6_use_tempaddr && 588 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 589 (oldflags & IN6_IFF_DEPRECATED) == 0) { 590 591 if (regen_tmpaddr(ia6) == 0) { 592 /* 593 * A new temporary address is 594 * generated. 595 * XXX: this means the address chain 596 * has changed while we are still in 597 * the loop. Although the change 598 * would not cause disaster (because 599 * it's not a deletion, but an 600 * addition,) we'd rather restart the 601 * loop just for safety. Or does this 602 * significantly reduce performance?? 603 */ 604 goto addrloop; 605 } 606 } 607 } else { 608 /* 609 * A new RA might have made a deprecated address 610 * preferred. 611 */ 612 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 613 } 614 } 615 616 /* expire prefix list */ 617 for (pr = LIST_FIRST(&nd_prefix); pr != NULL; pr = next_pr) { 618 next_pr = LIST_NEXT(pr, ndpr_entry); 619 /* 620 * check prefix lifetime. 621 * since pltime is just for autoconf, pltime processing for 622 * prefix is not necessary. 623 */ 624 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && 625 time_second - pr->ndpr_lastupdate > pr->ndpr_vltime) { 626 627 /* 628 * address expiration and prefix expiration are 629 * separate. NEVER perform in6_purgeaddr here. 630 */ 631 632 prelist_remove(pr); 633 } 634 } 635 636 KERNEL_UNLOCK_ONE(NULL); 637 mutex_exit(softnet_lock); 638 } 639 640 /* ia6: deprecated/invalidated temporary address */ 641 static int 642 regen_tmpaddr(struct in6_ifaddr *ia6) 643 { 644 struct ifaddr *ifa; 645 struct ifnet *ifp; 646 struct in6_ifaddr *public_ifa6 = NULL; 647 648 ifp = ia6->ia_ifa.ifa_ifp; 649 IFADDR_FOREACH(ifa, ifp) { 650 struct in6_ifaddr *it6; 651 652 if (ifa->ifa_addr->sa_family != AF_INET6) 653 continue; 654 655 it6 = (struct in6_ifaddr *)ifa; 656 657 /* ignore no autoconf addresses. */ 658 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 659 continue; 660 661 /* ignore autoconf addresses with different prefixes. */ 662 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 663 continue; 664 665 /* 666 * Now we are looking at an autoconf address with the same 667 * prefix as ours. If the address is temporary and is still 668 * preferred, do not create another one. It would be rare, but 669 * could happen, for example, when we resume a laptop PC after 670 * a long period. 671 */ 672 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 673 !IFA6_IS_DEPRECATED(it6)) { 674 public_ifa6 = NULL; 675 break; 676 } 677 678 /* 679 * This is a public autoconf address that has the same prefix 680 * as ours. If it is preferred, keep it. We can't break the 681 * loop here, because there may be a still-preferred temporary 682 * address with the prefix. 683 */ 684 if (!IFA6_IS_DEPRECATED(it6)) 685 public_ifa6 = it6; 686 } 687 688 if (public_ifa6 != NULL) { 689 int e; 690 691 /* 692 * Random factor is introduced in the preferred lifetime, so 693 * we do not need additional delay (3rd arg to in6_tmpifadd). 694 */ 695 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 696 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 697 " tmp addr, errno=%d\n", e); 698 return -1; 699 } 700 return 0; 701 } 702 703 return -1; 704 } 705 706 /* 707 * Nuke neighbor cache/prefix/default router management table, right before 708 * ifp goes away. 709 */ 710 void 711 nd6_purge(struct ifnet *ifp) 712 { 713 struct llinfo_nd6 *ln, *nln; 714 struct nd_defrouter *dr, *ndr; 715 struct nd_prefix *pr, *npr; 716 717 /* 718 * Nuke default router list entries toward ifp. 719 * We defer removal of default router list entries that is installed 720 * in the routing table, in order to keep additional side effects as 721 * small as possible. 722 */ 723 for (dr = TAILQ_FIRST(&nd_defrouter); dr != NULL; dr = ndr) { 724 ndr = TAILQ_NEXT(dr, dr_entry); 725 if (dr->installed) 726 continue; 727 728 if (dr->ifp == ifp) 729 defrtrlist_del(dr); 730 } 731 for (dr = TAILQ_FIRST(&nd_defrouter); dr != NULL; dr = ndr) { 732 ndr = TAILQ_NEXT(dr, dr_entry); 733 if (!dr->installed) 734 continue; 735 736 if (dr->ifp == ifp) 737 defrtrlist_del(dr); 738 } 739 740 /* Nuke prefix list entries toward ifp */ 741 for (pr = LIST_FIRST(&nd_prefix); pr != NULL; pr = npr) { 742 npr = LIST_NEXT(pr, ndpr_entry); 743 if (pr->ndpr_ifp == ifp) { 744 /* 745 * Because if_detach() does *not* release prefixes 746 * while purging addresses the reference count will 747 * still be above zero. We therefore reset it to 748 * make sure that the prefix really gets purged. 749 */ 750 pr->ndpr_refcnt = 0; 751 /* 752 * Previously, pr->ndpr_addr is removed as well, 753 * but I strongly believe we don't have to do it. 754 * nd6_purge() is only called from in6_ifdetach(), 755 * which removes all the associated interface addresses 756 * by itself. 757 * (jinmei@kame.net 20010129) 758 */ 759 prelist_remove(pr); 760 } 761 } 762 763 /* cancel default outgoing interface setting */ 764 if (nd6_defifindex == ifp->if_index) 765 nd6_setdefaultiface(0); 766 767 if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */ 768 /* refresh default router list */ 769 defrouter_select(); 770 } 771 772 /* 773 * Nuke neighbor cache entries for the ifp. 774 * Note that rt->rt_ifp may not be the same as ifp, 775 * due to KAME goto ours hack. See RTM_RESOLVE case in 776 * nd6_rtrequest(), and ip6_input(). 777 */ 778 ln = llinfo_nd6.ln_next; 779 while (ln != NULL && ln != &llinfo_nd6) { 780 struct rtentry *rt; 781 const struct sockaddr_dl *sdl; 782 783 nln = ln->ln_next; 784 rt = ln->ln_rt; 785 if (rt && rt->rt_gateway && 786 rt->rt_gateway->sa_family == AF_LINK) { 787 sdl = satocsdl(rt->rt_gateway); 788 if (sdl->sdl_index == ifp->if_index) 789 nln = nd6_free(rt, 0); 790 } 791 ln = nln; 792 } 793 } 794 795 struct rtentry * 796 nd6_lookup(const struct in6_addr *addr6, int create, struct ifnet *ifp) 797 { 798 struct rtentry *rt; 799 struct sockaddr_in6 sin6; 800 801 sockaddr_in6_init(&sin6, addr6, 0, 0, 0); 802 rt = rtalloc1((struct sockaddr *)&sin6, create); 803 if (rt != NULL && (rt->rt_flags & RTF_LLINFO) == 0) { 804 /* 805 * This is the case for the default route. 806 * If we want to create a neighbor cache for the address, we 807 * should free the route for the destination and allocate an 808 * interface route. 809 */ 810 if (create) { 811 RTFREE(rt); 812 rt = NULL; 813 } 814 } 815 if (rt != NULL) 816 ; 817 else if (create && ifp) { 818 int e; 819 820 /* 821 * If no route is available and create is set, 822 * we allocate a host route for the destination 823 * and treat it like an interface route. 824 * This hack is necessary for a neighbor which can't 825 * be covered by our own prefix. 826 */ 827 struct ifaddr *ifa = 828 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp); 829 if (ifa == NULL) 830 return NULL; 831 832 /* 833 * Create a new route. RTF_LLINFO is necessary 834 * to create a Neighbor Cache entry for the 835 * destination in nd6_rtrequest which will be 836 * called in rtrequest via ifa->ifa_rtrequest. 837 */ 838 if ((e = rtrequest(RTM_ADD, (const struct sockaddr *)&sin6, 839 ifa->ifa_addr, (const struct sockaddr *)&all1_sa, 840 (ifa->ifa_flags | RTF_HOST | RTF_LLINFO) & 841 ~RTF_CLONING, &rt)) != 0) { 842 #if 0 843 log(LOG_ERR, 844 "nd6_lookup: failed to add route for a " 845 "neighbor(%s), errno=%d\n", 846 ip6_sprintf(addr6), e); 847 #endif 848 return NULL; 849 } 850 if (rt == NULL) 851 return NULL; 852 if (rt->rt_llinfo) { 853 struct llinfo_nd6 *ln = 854 (struct llinfo_nd6 *)rt->rt_llinfo; 855 ln->ln_state = ND6_LLINFO_NOSTATE; 856 } 857 } else 858 return NULL; 859 rt->rt_refcnt--; 860 /* 861 * Validation for the entry. 862 * Note that the check for rt_llinfo is necessary because a cloned 863 * route from a parent route that has the L flag (e.g. the default 864 * route to a p2p interface) may have the flag, too, while the 865 * destination is not actually a neighbor. 866 * XXX: we can't use rt->rt_ifp to check for the interface, since 867 * it might be the loopback interface if the entry is for our 868 * own address on a non-loopback interface. Instead, we should 869 * use rt->rt_ifa->ifa_ifp, which would specify the REAL 870 * interface. 871 * Note also that ifa_ifp and ifp may differ when we connect two 872 * interfaces to a same link, install a link prefix to an interface, 873 * and try to install a neighbor cache on an interface that does not 874 * have a route to the prefix. 875 */ 876 if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 || 877 rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL || 878 (ifp && rt->rt_ifa->ifa_ifp != ifp)) { 879 if (create) { 880 nd6log((LOG_DEBUG, 881 "nd6_lookup: failed to lookup %s (if = %s)\n", 882 ip6_sprintf(addr6), 883 ifp ? if_name(ifp) : "unspec")); 884 } 885 return NULL; 886 } 887 return rt; 888 } 889 890 /* 891 * Detect if a given IPv6 address identifies a neighbor on a given link. 892 * XXX: should take care of the destination of a p2p link? 893 */ 894 int 895 nd6_is_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp) 896 { 897 struct nd_prefix *pr; 898 899 /* 900 * A link-local address is always a neighbor. 901 * XXX: a link does not necessarily specify a single interface. 902 */ 903 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 904 struct sockaddr_in6 sin6_copy; 905 u_int32_t zone; 906 907 /* 908 * We need sin6_copy since sa6_recoverscope() may modify the 909 * content (XXX). 910 */ 911 sin6_copy = *addr; 912 if (sa6_recoverscope(&sin6_copy)) 913 return 0; /* XXX: should be impossible */ 914 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 915 return 0; 916 if (sin6_copy.sin6_scope_id == zone) 917 return 1; 918 else 919 return 0; 920 } 921 922 /* 923 * If the address matches one of our on-link prefixes, it should be a 924 * neighbor. 925 */ 926 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 927 if (pr->ndpr_ifp != ifp) 928 continue; 929 930 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) 931 continue; 932 933 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 934 &addr->sin6_addr, &pr->ndpr_mask)) 935 return 1; 936 } 937 938 /* 939 * If the default router list is empty, all addresses are regarded 940 * as on-link, and thus, as a neighbor. 941 * XXX: we restrict the condition to hosts, because routers usually do 942 * not have the "default router list". 943 */ 944 if (!ip6_forwarding && TAILQ_FIRST(&nd_defrouter) == NULL && 945 nd6_defifindex == ifp->if_index) { 946 return 1; 947 } 948 949 /* 950 * Even if the address matches none of our addresses, it might be 951 * in the neighbor cache. 952 */ 953 if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL) 954 return 1; 955 956 return 0; 957 } 958 959 /* 960 * Free an nd6 llinfo entry. 961 * Since the function would cause significant changes in the kernel, DO NOT 962 * make it global, unless you have a strong reason for the change, and are sure 963 * that the change is safe. 964 */ 965 static struct llinfo_nd6 * 966 nd6_free(struct rtentry *rt, int gc) 967 { 968 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next; 969 struct in6_addr in6 = satocsin6(rt_getkey(rt))->sin6_addr; 970 struct nd_defrouter *dr; 971 972 /* 973 * we used to have pfctlinput(PRC_HOSTDEAD) here. 974 * even though it is not harmful, it was not really necessary. 975 */ 976 977 /* cancel timer */ 978 nd6_llinfo_settimer(ln, -1); 979 980 if (!ip6_forwarding) { 981 int s; 982 s = splsoftnet(); 983 dr = defrouter_lookup(&satocsin6(rt_getkey(rt))->sin6_addr, 984 rt->rt_ifp); 985 986 if (dr != NULL && dr->expire && 987 ln->ln_state == ND6_LLINFO_STALE && gc) { 988 /* 989 * If the reason for the deletion is just garbage 990 * collection, and the neighbor is an active default 991 * router, do not delete it. Instead, reset the GC 992 * timer using the router's lifetime. 993 * Simply deleting the entry would affect default 994 * router selection, which is not necessarily a good 995 * thing, especially when we're using router preference 996 * values. 997 * XXX: the check for ln_state would be redundant, 998 * but we intentionally keep it just in case. 999 */ 1000 if (dr->expire > time_second) 1001 nd6_llinfo_settimer(ln, 1002 (dr->expire - time_second) * hz); 1003 else 1004 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1005 splx(s); 1006 return ln->ln_next; 1007 } 1008 1009 if (ln->ln_router || dr) { 1010 /* 1011 * rt6_flush must be called whether or not the neighbor 1012 * is in the Default Router List. 1013 * See a corresponding comment in nd6_na_input(). 1014 */ 1015 rt6_flush(&in6, rt->rt_ifp); 1016 } 1017 1018 if (dr) { 1019 /* 1020 * Unreachablity of a router might affect the default 1021 * router selection and on-link detection of advertised 1022 * prefixes. 1023 */ 1024 1025 /* 1026 * Temporarily fake the state to choose a new default 1027 * router and to perform on-link determination of 1028 * prefixes correctly. 1029 * Below the state will be set correctly, 1030 * or the entry itself will be deleted. 1031 */ 1032 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1033 1034 /* 1035 * Since defrouter_select() does not affect the 1036 * on-link determination and MIP6 needs the check 1037 * before the default router selection, we perform 1038 * the check now. 1039 */ 1040 pfxlist_onlink_check(); 1041 1042 /* 1043 * refresh default router list 1044 */ 1045 defrouter_select(); 1046 } 1047 splx(s); 1048 } 1049 1050 /* 1051 * Before deleting the entry, remember the next entry as the 1052 * return value. We need this because pfxlist_onlink_check() above 1053 * might have freed other entries (particularly the old next entry) as 1054 * a side effect (XXX). 1055 */ 1056 next = ln->ln_next; 1057 1058 /* 1059 * Detach the route from the routing tree and the list of neighbor 1060 * caches, and disable the route entry not to be used in already 1061 * cached routes. 1062 */ 1063 rtrequest(RTM_DELETE, rt_getkey(rt), NULL, rt_mask(rt), 0, NULL); 1064 1065 return next; 1066 } 1067 1068 /* 1069 * Upper-layer reachability hint for Neighbor Unreachability Detection. 1070 * 1071 * XXX cost-effective methods? 1072 */ 1073 void 1074 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force) 1075 { 1076 struct llinfo_nd6 *ln; 1077 1078 /* 1079 * If the caller specified "rt", use that. Otherwise, resolve the 1080 * routing table by supplied "dst6". 1081 */ 1082 if (rt == NULL) { 1083 if (dst6 == NULL) 1084 return; 1085 if ((rt = nd6_lookup(dst6, 0, NULL)) == NULL) 1086 return; 1087 } 1088 1089 if ((rt->rt_flags & RTF_GATEWAY) != 0 || 1090 (rt->rt_flags & RTF_LLINFO) == 0 || 1091 !rt->rt_llinfo || !rt->rt_gateway || 1092 rt->rt_gateway->sa_family != AF_LINK) { 1093 /* This is not a host route. */ 1094 return; 1095 } 1096 1097 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1098 if (ln->ln_state < ND6_LLINFO_REACHABLE) 1099 return; 1100 1101 /* 1102 * if we get upper-layer reachability confirmation many times, 1103 * it is possible we have false information. 1104 */ 1105 if (!force) { 1106 ln->ln_byhint++; 1107 if (ln->ln_byhint > nd6_maxnudhint) 1108 return; 1109 } 1110 1111 ln->ln_state = ND6_LLINFO_REACHABLE; 1112 if (!ND6_LLINFO_PERMANENT(ln)) { 1113 nd6_llinfo_settimer(ln, 1114 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 1115 } 1116 } 1117 1118 void 1119 nd6_rtrequest(int req, struct rtentry *rt, const struct rt_addrinfo *info) 1120 { 1121 struct sockaddr *gate = rt->rt_gateway; 1122 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1123 struct ifnet *ifp = rt->rt_ifp; 1124 uint8_t namelen = strlen(ifp->if_xname), addrlen = ifp->if_addrlen; 1125 struct ifaddr *ifa; 1126 1127 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1128 1129 if (req == RTM_LLINFO_UPD) { 1130 int rc; 1131 struct in6_addr *in6; 1132 struct in6_addr in6_all; 1133 int anycast; 1134 1135 if ((ifa = info->rti_ifa) == NULL) 1136 return; 1137 1138 in6 = &ifatoia6(ifa)->ia_addr.sin6_addr; 1139 anycast = ifatoia6(ifa)->ia6_flags & IN6_IFF_ANYCAST; 1140 1141 in6_all = in6addr_linklocal_allnodes; 1142 if ((rc = in6_setscope(&in6_all, ifa->ifa_ifp, NULL)) != 0) { 1143 log(LOG_ERR, "%s: failed to set scope %s " 1144 "(errno=%d)\n", __func__, if_name(ifp), rc); 1145 return; 1146 } 1147 1148 /* XXX don't set Override for proxy addresses */ 1149 nd6_na_output(ifa->ifa_ifp, &in6_all, in6, 1150 (anycast ? 0 : ND_NA_FLAG_OVERRIDE) 1151 #if 0 1152 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) 1153 #endif 1154 , 1, NULL); 1155 return; 1156 } 1157 1158 if ((rt->rt_flags & RTF_GATEWAY) != 0) 1159 return; 1160 1161 if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) { 1162 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1163 /* 1164 * This is probably an interface direct route for a link 1165 * which does not need neighbor caches (e.g. fe80::%lo0/64). 1166 * We do not need special treatment below for such a route. 1167 * Moreover, the RTF_LLINFO flag which would be set below 1168 * would annoy the ndp(8) command. 1169 */ 1170 return; 1171 } 1172 1173 if (req == RTM_RESOLVE && 1174 (nd6_need_cache(ifp) == 0 || /* stf case */ 1175 !nd6_is_addr_neighbor(satocsin6(rt_getkey(rt)), ifp))) { 1176 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1177 /* 1178 * FreeBSD and BSD/OS often make a cloned host route based 1179 * on a less-specific route (e.g. the default route). 1180 * If the less specific route does not have a "gateway" 1181 * (this is the case when the route just goes to a p2p or an 1182 * stf interface), we'll mistakenly make a neighbor cache for 1183 * the host route, and will see strange neighbor solicitation 1184 * for the corresponding destination. In order to avoid the 1185 * confusion, we check if the destination of the route is 1186 * a neighbor in terms of neighbor discovery, and stop the 1187 * process if not. Additionally, we remove the LLINFO flag 1188 * so that ndp(8) will not try to get the neighbor information 1189 * of the destination. 1190 */ 1191 rt->rt_flags &= ~RTF_LLINFO; 1192 return; 1193 } 1194 1195 switch (req) { 1196 case RTM_ADD: 1197 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1198 /* 1199 * There is no backward compatibility :) 1200 * 1201 * if ((rt->rt_flags & RTF_HOST) == 0 && 1202 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 1203 * rt->rt_flags |= RTF_CLONING; 1204 */ 1205 if ((rt->rt_flags & RTF_CLONING) || 1206 ((rt->rt_flags & RTF_LLINFO) && ln == NULL)) { 1207 union { 1208 struct sockaddr sa; 1209 struct sockaddr_dl sdl; 1210 struct sockaddr_storage ss; 1211 } u; 1212 /* 1213 * Case 1: This route should come from a route to 1214 * interface (RTF_CLONING case) or the route should be 1215 * treated as on-link but is currently not 1216 * (RTF_LLINFO && ln == NULL case). 1217 */ 1218 sockaddr_dl_init(&u.sdl, sizeof(u.ss), 1219 ifp->if_index, ifp->if_type, 1220 NULL, namelen, NULL, addrlen); 1221 rt_setgate(rt, &u.sa); 1222 gate = rt->rt_gateway; 1223 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1224 if (ln != NULL) 1225 nd6_llinfo_settimer(ln, 0); 1226 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1227 if ((rt->rt_flags & RTF_CLONING) != 0) 1228 break; 1229 } 1230 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1231 /* 1232 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here. 1233 * We don't do that here since llinfo is not ready yet. 1234 * 1235 * There are also couple of other things to be discussed: 1236 * - unsolicited NA code needs improvement beforehand 1237 * - RFC2461 says we MAY send multicast unsolicited NA 1238 * (7.2.6 paragraph 4), however, it also says that we 1239 * SHOULD provide a mechanism to prevent multicast NA storm. 1240 * we don't have anything like it right now. 1241 * note that the mechanism needs a mutual agreement 1242 * between proxies, which means that we need to implement 1243 * a new protocol, or a new kludge. 1244 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA. 1245 * we need to check ip6forwarding before sending it. 1246 * (or should we allow proxy ND configuration only for 1247 * routers? there's no mention about proxy ND from hosts) 1248 */ 1249 #if 0 1250 /* XXX it does not work */ 1251 if (rt->rt_flags & RTF_ANNOUNCE) 1252 nd6_na_output(ifp, 1253 &satocsin6(rt_getkey(rt))->sin6_addr, 1254 &satocsin6(rt_getkey(rt))->sin6_addr, 1255 ip6_forwarding ? ND_NA_FLAG_ROUTER : 0, 1256 1, NULL); 1257 #endif 1258 /* FALLTHROUGH */ 1259 case RTM_RESOLVE: 1260 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) { 1261 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1262 /* 1263 * Address resolution isn't necessary for a point to 1264 * point link, so we can skip this test for a p2p link. 1265 */ 1266 if (gate->sa_family != AF_LINK || 1267 gate->sa_len < 1268 sockaddr_dl_measure(namelen, addrlen)) { 1269 log(LOG_DEBUG, 1270 "nd6_rtrequest: bad gateway value: %s\n", 1271 if_name(ifp)); 1272 break; 1273 } 1274 satosdl(gate)->sdl_type = ifp->if_type; 1275 satosdl(gate)->sdl_index = ifp->if_index; 1276 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1277 } 1278 if (ln != NULL) 1279 break; /* This happens on a route change */ 1280 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1281 /* 1282 * Case 2: This route may come from cloning, or a manual route 1283 * add with a LL address. 1284 */ 1285 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln)); 1286 rt->rt_llinfo = ln; 1287 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1288 if (ln == NULL) { 1289 log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n"); 1290 break; 1291 } 1292 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1293 nd6_inuse++; 1294 nd6_allocated++; 1295 memset(ln, 0, sizeof(*ln)); 1296 ln->ln_rt = rt; 1297 callout_init(&ln->ln_timer_ch, CALLOUT_MPSAFE); 1298 /* this is required for "ndp" command. - shin */ 1299 if (req == RTM_ADD) { 1300 /* 1301 * gate should have some valid AF_LINK entry, 1302 * and ln->ln_expire should have some lifetime 1303 * which is specified by ndp command. 1304 */ 1305 ln->ln_state = ND6_LLINFO_REACHABLE; 1306 ln->ln_byhint = 0; 1307 } else { 1308 /* 1309 * When req == RTM_RESOLVE, rt is created and 1310 * initialized in rtrequest(), so rt_expire is 0. 1311 */ 1312 ln->ln_state = ND6_LLINFO_NOSTATE; 1313 nd6_llinfo_settimer(ln, 0); 1314 } 1315 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1316 rt->rt_flags |= RTF_LLINFO; 1317 ln->ln_next = llinfo_nd6.ln_next; 1318 llinfo_nd6.ln_next = ln; 1319 ln->ln_prev = &llinfo_nd6; 1320 ln->ln_next->ln_prev = ln; 1321 1322 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1323 /* 1324 * check if rt_getkey(rt) is an address assigned 1325 * to the interface. 1326 */ 1327 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 1328 &satocsin6(rt_getkey(rt))->sin6_addr); 1329 RT_DPRINTF("rt->_rt_key = %p\n", (void *)rt->_rt_key); 1330 if (ifa != NULL) { 1331 const void *mac; 1332 nd6_llinfo_settimer(ln, -1); 1333 ln->ln_state = ND6_LLINFO_REACHABLE; 1334 ln->ln_byhint = 0; 1335 if ((mac = nd6_ifptomac(ifp)) != NULL) { 1336 /* XXX check for error */ 1337 (void)sockaddr_dl_setaddr(satosdl(gate), 1338 gate->sa_len, mac, ifp->if_addrlen); 1339 } 1340 if (nd6_useloopback) { 1341 ifp = rt->rt_ifp = lo0ifp; /* XXX */ 1342 /* 1343 * Make sure rt_ifa be equal to the ifaddr 1344 * corresponding to the address. 1345 * We need this because when we refer 1346 * rt_ifa->ia6_flags in ip6_input, we assume 1347 * that the rt_ifa points to the address instead 1348 * of the loopback address. 1349 */ 1350 if (ifa != rt->rt_ifa) 1351 rt_replace_ifa(rt, ifa); 1352 rt->rt_flags &= ~RTF_CLONED; 1353 } 1354 } else if (rt->rt_flags & RTF_ANNOUNCE) { 1355 nd6_llinfo_settimer(ln, -1); 1356 ln->ln_state = ND6_LLINFO_REACHABLE; 1357 ln->ln_byhint = 0; 1358 1359 /* join solicited node multicast for proxy ND */ 1360 if (ifp->if_flags & IFF_MULTICAST) { 1361 struct in6_addr llsol; 1362 int error; 1363 1364 llsol = satocsin6(rt_getkey(rt))->sin6_addr; 1365 llsol.s6_addr32[0] = htonl(0xff020000); 1366 llsol.s6_addr32[1] = 0; 1367 llsol.s6_addr32[2] = htonl(1); 1368 llsol.s6_addr8[12] = 0xff; 1369 if (in6_setscope(&llsol, ifp, NULL)) 1370 break; 1371 if (!in6_addmulti(&llsol, ifp, &error, 0)) { 1372 nd6log((LOG_ERR, "%s: failed to join " 1373 "%s (errno=%d)\n", if_name(ifp), 1374 ip6_sprintf(&llsol), error)); 1375 } 1376 } 1377 } 1378 break; 1379 1380 case RTM_DELETE: 1381 if (ln == NULL) 1382 break; 1383 /* leave from solicited node multicast for proxy ND */ 1384 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 && 1385 (ifp->if_flags & IFF_MULTICAST) != 0) { 1386 struct in6_addr llsol; 1387 struct in6_multi *in6m; 1388 1389 llsol = satocsin6(rt_getkey(rt))->sin6_addr; 1390 llsol.s6_addr32[0] = htonl(0xff020000); 1391 llsol.s6_addr32[1] = 0; 1392 llsol.s6_addr32[2] = htonl(1); 1393 llsol.s6_addr8[12] = 0xff; 1394 if (in6_setscope(&llsol, ifp, NULL) == 0) { 1395 IN6_LOOKUP_MULTI(llsol, ifp, in6m); 1396 if (in6m) 1397 in6_delmulti(in6m); 1398 } 1399 } 1400 nd6_inuse--; 1401 ln->ln_next->ln_prev = ln->ln_prev; 1402 ln->ln_prev->ln_next = ln->ln_next; 1403 ln->ln_prev = NULL; 1404 nd6_llinfo_settimer(ln, -1); 1405 rt->rt_llinfo = 0; 1406 rt->rt_flags &= ~RTF_LLINFO; 1407 clear_llinfo_pqueue(ln); 1408 Free(ln); 1409 } 1410 } 1411 1412 int 1413 nd6_ioctl(u_long cmd, void *data, struct ifnet *ifp) 1414 { 1415 struct in6_drlist *drl = (struct in6_drlist *)data; 1416 struct in6_oprlist *oprl = (struct in6_oprlist *)data; 1417 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1418 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1419 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1420 struct nd_defrouter *dr; 1421 struct nd_prefix *pr; 1422 struct rtentry *rt; 1423 int i = 0, error = 0; 1424 int s; 1425 1426 switch (cmd) { 1427 case SIOCGDRLST_IN6: 1428 /* 1429 * obsolete API, use sysctl under net.inet6.icmp6 1430 */ 1431 memset(drl, 0, sizeof(*drl)); 1432 s = splsoftnet(); 1433 TAILQ_FOREACH(dr, &nd_defrouter, dr_entry) { 1434 if (i >= DRLSTSIZ) 1435 break; 1436 drl->defrouter[i].rtaddr = dr->rtaddr; 1437 in6_clearscope(&drl->defrouter[i].rtaddr); 1438 1439 drl->defrouter[i].flags = dr->flags; 1440 drl->defrouter[i].rtlifetime = dr->rtlifetime; 1441 drl->defrouter[i].expire = dr->expire; 1442 drl->defrouter[i].if_index = dr->ifp->if_index; 1443 i++; 1444 } 1445 splx(s); 1446 break; 1447 case SIOCGPRLST_IN6: 1448 /* 1449 * obsolete API, use sysctl under net.inet6.icmp6 1450 * 1451 * XXX the structure in6_prlist was changed in backward- 1452 * incompatible manner. in6_oprlist is used for SIOCGPRLST_IN6, 1453 * in6_prlist is used for nd6_sysctl() - fill_prlist(). 1454 */ 1455 /* 1456 * XXX meaning of fields, especialy "raflags", is very 1457 * differnet between RA prefix list and RR/static prefix list. 1458 * how about separating ioctls into two? 1459 */ 1460 memset(oprl, 0, sizeof(*oprl)); 1461 s = splsoftnet(); 1462 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 1463 struct nd_pfxrouter *pfr; 1464 int j; 1465 1466 if (i >= PRLSTSIZ) 1467 break; 1468 oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr; 1469 oprl->prefix[i].raflags = pr->ndpr_raf; 1470 oprl->prefix[i].prefixlen = pr->ndpr_plen; 1471 oprl->prefix[i].vltime = pr->ndpr_vltime; 1472 oprl->prefix[i].pltime = pr->ndpr_pltime; 1473 oprl->prefix[i].if_index = pr->ndpr_ifp->if_index; 1474 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1475 oprl->prefix[i].expire = 0; 1476 else { 1477 time_t maxexpire; 1478 1479 /* XXX: we assume time_t is signed. */ 1480 maxexpire = (-1) & 1481 ~((time_t)1 << 1482 ((sizeof(maxexpire) * 8) - 1)); 1483 if (pr->ndpr_vltime < 1484 maxexpire - pr->ndpr_lastupdate) { 1485 oprl->prefix[i].expire = 1486 pr->ndpr_lastupdate + 1487 pr->ndpr_vltime; 1488 } else 1489 oprl->prefix[i].expire = maxexpire; 1490 } 1491 1492 j = 0; 1493 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) { 1494 if (j < DRLSTSIZ) { 1495 #define RTRADDR oprl->prefix[i].advrtr[j] 1496 RTRADDR = pfr->router->rtaddr; 1497 in6_clearscope(&RTRADDR); 1498 #undef RTRADDR 1499 } 1500 j++; 1501 } 1502 oprl->prefix[i].advrtrs = j; 1503 oprl->prefix[i].origin = PR_ORIG_RA; 1504 1505 i++; 1506 } 1507 splx(s); 1508 1509 break; 1510 case OSIOCGIFINFO_IN6: 1511 #define ND ndi->ndi 1512 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1513 memset(&ND, 0, sizeof(ND)); 1514 ND.linkmtu = IN6_LINKMTU(ifp); 1515 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1516 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1517 ND.reachable = ND_IFINFO(ifp)->reachable; 1518 ND.retrans = ND_IFINFO(ifp)->retrans; 1519 ND.flags = ND_IFINFO(ifp)->flags; 1520 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1521 ND.chlim = ND_IFINFO(ifp)->chlim; 1522 break; 1523 case SIOCGIFINFO_IN6: 1524 ND = *ND_IFINFO(ifp); 1525 break; 1526 case SIOCSIFINFO_IN6: 1527 /* 1528 * used to change host variables from userland. 1529 * intented for a use on router to reflect RA configurations. 1530 */ 1531 /* 0 means 'unspecified' */ 1532 if (ND.linkmtu != 0) { 1533 if (ND.linkmtu < IPV6_MMTU || 1534 ND.linkmtu > IN6_LINKMTU(ifp)) { 1535 error = EINVAL; 1536 break; 1537 } 1538 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1539 } 1540 1541 if (ND.basereachable != 0) { 1542 int obasereachable = ND_IFINFO(ifp)->basereachable; 1543 1544 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1545 if (ND.basereachable != obasereachable) 1546 ND_IFINFO(ifp)->reachable = 1547 ND_COMPUTE_RTIME(ND.basereachable); 1548 } 1549 if (ND.retrans != 0) 1550 ND_IFINFO(ifp)->retrans = ND.retrans; 1551 if (ND.chlim != 0) 1552 ND_IFINFO(ifp)->chlim = ND.chlim; 1553 /* FALLTHROUGH */ 1554 case SIOCSIFINFO_FLAGS: 1555 ND_IFINFO(ifp)->flags = ND.flags; 1556 break; 1557 #undef ND 1558 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1559 /* sync kernel routing table with the default router list */ 1560 defrouter_reset(); 1561 defrouter_select(); 1562 break; 1563 case SIOCSPFXFLUSH_IN6: 1564 { 1565 /* flush all the prefix advertised by routers */ 1566 struct nd_prefix *pfx, *next; 1567 1568 s = splsoftnet(); 1569 for (pfx = LIST_FIRST(&nd_prefix); pfx; pfx = next) { 1570 struct in6_ifaddr *ia, *ia_next; 1571 1572 next = LIST_NEXT(pfx, ndpr_entry); 1573 1574 if (IN6_IS_ADDR_LINKLOCAL(&pfx->ndpr_prefix.sin6_addr)) 1575 continue; /* XXX */ 1576 1577 /* do we really have to remove addresses as well? */ 1578 for (ia = in6_ifaddr; ia; ia = ia_next) { 1579 /* ia might be removed. keep the next ptr. */ 1580 ia_next = ia->ia_next; 1581 1582 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1583 continue; 1584 1585 if (ia->ia6_ndpr == pfx) 1586 in6_purgeaddr(&ia->ia_ifa); 1587 } 1588 prelist_remove(pfx); 1589 } 1590 splx(s); 1591 break; 1592 } 1593 case SIOCSRTRFLUSH_IN6: 1594 { 1595 /* flush all the default routers */ 1596 struct nd_defrouter *drtr, *next; 1597 1598 s = splsoftnet(); 1599 defrouter_reset(); 1600 for (drtr = TAILQ_FIRST(&nd_defrouter); drtr; drtr = next) { 1601 next = TAILQ_NEXT(drtr, dr_entry); 1602 defrtrlist_del(drtr); 1603 } 1604 defrouter_select(); 1605 splx(s); 1606 break; 1607 } 1608 case SIOCGNBRINFO_IN6: 1609 { 1610 struct llinfo_nd6 *ln; 1611 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1612 1613 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1614 return error; 1615 1616 s = splsoftnet(); 1617 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL || 1618 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) { 1619 error = EINVAL; 1620 splx(s); 1621 break; 1622 } 1623 nbi->state = ln->ln_state; 1624 nbi->asked = ln->ln_asked; 1625 nbi->isrouter = ln->ln_router; 1626 nbi->expire = ln->ln_expire; 1627 splx(s); 1628 1629 break; 1630 } 1631 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1632 ndif->ifindex = nd6_defifindex; 1633 break; 1634 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1635 return nd6_setdefaultiface(ndif->ifindex); 1636 } 1637 return error; 1638 } 1639 1640 void 1641 nd6_llinfo_release_pkts(struct llinfo_nd6 *ln, struct ifnet *ifp, 1642 struct rtentry *rt) 1643 { 1644 struct mbuf *m_hold, *m_hold_next; 1645 1646 for (m_hold = ln->ln_hold, ln->ln_hold = NULL; 1647 m_hold != NULL; 1648 m_hold = m_hold_next) { 1649 m_hold_next = m_hold->m_nextpkt; 1650 m_hold->m_nextpkt = NULL; 1651 1652 /* 1653 * we assume ifp is not a p2p here, so 1654 * just set the 2nd argument as the 1655 * 1st one. 1656 */ 1657 nd6_output(ifp, ifp, m_hold, satocsin6(rt_getkey(rt)), rt); 1658 } 1659 } 1660 1661 /* 1662 * Create neighbor cache entry and cache link-layer address, 1663 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1664 */ 1665 struct rtentry * 1666 nd6_cache_lladdr( 1667 struct ifnet *ifp, 1668 struct in6_addr *from, 1669 char *lladdr, 1670 int lladdrlen, 1671 int type, /* ICMP6 type */ 1672 int code /* type dependent information */ 1673 ) 1674 { 1675 struct rtentry *rt = NULL; 1676 struct llinfo_nd6 *ln = NULL; 1677 int is_newentry; 1678 struct sockaddr_dl *sdl = NULL; 1679 int do_update; 1680 int olladdr; 1681 int llchange; 1682 int newstate = 0; 1683 1684 if (ifp == NULL) 1685 panic("ifp == NULL in nd6_cache_lladdr"); 1686 if (from == NULL) 1687 panic("from == NULL in nd6_cache_lladdr"); 1688 1689 /* nothing must be updated for unspecified address */ 1690 if (IN6_IS_ADDR_UNSPECIFIED(from)) 1691 return NULL; 1692 1693 /* 1694 * Validation about ifp->if_addrlen and lladdrlen must be done in 1695 * the caller. 1696 * 1697 * XXX If the link does not have link-layer adderss, what should 1698 * we do? (ifp->if_addrlen == 0) 1699 * Spec says nothing in sections for RA, RS and NA. There's small 1700 * description on it in NS section (RFC 2461 7.2.3). 1701 */ 1702 1703 rt = nd6_lookup(from, 0, ifp); 1704 if (rt == NULL) { 1705 #if 0 1706 /* nothing must be done if there's no lladdr */ 1707 if (!lladdr || !lladdrlen) 1708 return NULL; 1709 #endif 1710 1711 rt = nd6_lookup(from, 1, ifp); 1712 is_newentry = 1; 1713 } else { 1714 /* do nothing if static ndp is set */ 1715 if (rt->rt_flags & RTF_STATIC) 1716 return NULL; 1717 is_newentry = 0; 1718 } 1719 1720 if (rt == NULL) 1721 return NULL; 1722 if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) { 1723 fail: 1724 (void)nd6_free(rt, 0); 1725 return NULL; 1726 } 1727 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1728 if (ln == NULL) 1729 goto fail; 1730 if (rt->rt_gateway == NULL) 1731 goto fail; 1732 if (rt->rt_gateway->sa_family != AF_LINK) 1733 goto fail; 1734 sdl = satosdl(rt->rt_gateway); 1735 1736 olladdr = (sdl->sdl_alen) ? 1 : 0; 1737 if (olladdr && lladdr) { 1738 if (memcmp(lladdr, CLLADDR(sdl), ifp->if_addrlen)) 1739 llchange = 1; 1740 else 1741 llchange = 0; 1742 } else 1743 llchange = 0; 1744 1745 /* 1746 * newentry olladdr lladdr llchange (*=record) 1747 * 0 n n -- (1) 1748 * 0 y n -- (2) 1749 * 0 n y -- (3) * STALE 1750 * 0 y y n (4) * 1751 * 0 y y y (5) * STALE 1752 * 1 -- n -- (6) NOSTATE(= PASSIVE) 1753 * 1 -- y -- (7) * STALE 1754 */ 1755 1756 if (lladdr) { /* (3-5) and (7) */ 1757 /* 1758 * Record source link-layer address 1759 * XXX is it dependent to ifp->if_type? 1760 */ 1761 /* XXX check for error */ 1762 (void)sockaddr_dl_setaddr(sdl, sdl->sdl_len, lladdr, 1763 ifp->if_addrlen); 1764 } 1765 1766 if (!is_newentry) { 1767 if ((!olladdr && lladdr) || /* (3) */ 1768 (olladdr && lladdr && llchange)) { /* (5) */ 1769 do_update = 1; 1770 newstate = ND6_LLINFO_STALE; 1771 } else /* (1-2,4) */ 1772 do_update = 0; 1773 } else { 1774 do_update = 1; 1775 if (lladdr == NULL) /* (6) */ 1776 newstate = ND6_LLINFO_NOSTATE; 1777 else /* (7) */ 1778 newstate = ND6_LLINFO_STALE; 1779 } 1780 1781 if (do_update) { 1782 /* 1783 * Update the state of the neighbor cache. 1784 */ 1785 ln->ln_state = newstate; 1786 1787 if (ln->ln_state == ND6_LLINFO_STALE) { 1788 /* 1789 * XXX: since nd6_output() below will cause 1790 * state tansition to DELAY and reset the timer, 1791 * we must set the timer now, although it is actually 1792 * meaningless. 1793 */ 1794 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 1795 1796 nd6_llinfo_release_pkts(ln, ifp, rt); 1797 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 1798 /* probe right away */ 1799 nd6_llinfo_settimer((void *)ln, 0); 1800 } 1801 } 1802 1803 /* 1804 * ICMP6 type dependent behavior. 1805 * 1806 * NS: clear IsRouter if new entry 1807 * RS: clear IsRouter 1808 * RA: set IsRouter if there's lladdr 1809 * redir: clear IsRouter if new entry 1810 * 1811 * RA case, (1): 1812 * The spec says that we must set IsRouter in the following cases: 1813 * - If lladdr exist, set IsRouter. This means (1-5). 1814 * - If it is old entry (!newentry), set IsRouter. This means (7). 1815 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1816 * A quetion arises for (1) case. (1) case has no lladdr in the 1817 * neighbor cache, this is similar to (6). 1818 * This case is rare but we figured that we MUST NOT set IsRouter. 1819 * 1820 * newentry olladdr lladdr llchange NS RS RA redir 1821 * D R 1822 * 0 n n -- (1) c ? s 1823 * 0 y n -- (2) c s s 1824 * 0 n y -- (3) c s s 1825 * 0 y y n (4) c s s 1826 * 0 y y y (5) c s s 1827 * 1 -- n -- (6) c c c s 1828 * 1 -- y -- (7) c c s c s 1829 * 1830 * (c=clear s=set) 1831 */ 1832 switch (type & 0xff) { 1833 case ND_NEIGHBOR_SOLICIT: 1834 /* 1835 * New entry must have is_router flag cleared. 1836 */ 1837 if (is_newentry) /* (6-7) */ 1838 ln->ln_router = 0; 1839 break; 1840 case ND_REDIRECT: 1841 /* 1842 * If the icmp is a redirect to a better router, always set the 1843 * is_router flag. Otherwise, if the entry is newly created, 1844 * clear the flag. [RFC 2461, sec 8.3] 1845 */ 1846 if (code == ND_REDIRECT_ROUTER) 1847 ln->ln_router = 1; 1848 else if (is_newentry) /* (6-7) */ 1849 ln->ln_router = 0; 1850 break; 1851 case ND_ROUTER_SOLICIT: 1852 /* 1853 * is_router flag must always be cleared. 1854 */ 1855 ln->ln_router = 0; 1856 break; 1857 case ND_ROUTER_ADVERT: 1858 /* 1859 * Mark an entry with lladdr as a router. 1860 */ 1861 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */ 1862 (is_newentry && lladdr)) { /* (7) */ 1863 ln->ln_router = 1; 1864 } 1865 break; 1866 } 1867 1868 /* 1869 * When the link-layer address of a router changes, select the 1870 * best router again. In particular, when the neighbor entry is newly 1871 * created, it might affect the selection policy. 1872 * Question: can we restrict the first condition to the "is_newentry" 1873 * case? 1874 * XXX: when we hear an RA from a new router with the link-layer 1875 * address option, defrouter_select() is called twice, since 1876 * defrtrlist_update called the function as well. However, I believe 1877 * we can compromise the overhead, since it only happens the first 1878 * time. 1879 * XXX: although defrouter_select() should not have a bad effect 1880 * for those are not autoconfigured hosts, we explicitly avoid such 1881 * cases for safety. 1882 */ 1883 if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv) 1884 defrouter_select(); 1885 1886 return rt; 1887 } 1888 1889 static void 1890 nd6_slowtimo(void *ignored_arg) 1891 { 1892 struct nd_ifinfo *nd6if; 1893 struct ifnet *ifp; 1894 1895 mutex_enter(softnet_lock); 1896 KERNEL_LOCK(1, NULL); 1897 callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 1898 nd6_slowtimo, NULL); 1899 TAILQ_FOREACH(ifp, &ifnet, if_list) { 1900 nd6if = ND_IFINFO(ifp); 1901 if (nd6if->basereachable && /* already initialized */ 1902 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 1903 /* 1904 * Since reachable time rarely changes by router 1905 * advertisements, we SHOULD insure that a new random 1906 * value gets recomputed at least once every few hours. 1907 * (RFC 2461, 6.3.4) 1908 */ 1909 nd6if->recalctm = nd6_recalc_reachtm_interval; 1910 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 1911 } 1912 } 1913 KERNEL_UNLOCK_ONE(NULL); 1914 mutex_exit(softnet_lock); 1915 } 1916 1917 #define senderr(e) { error = (e); goto bad;} 1918 int 1919 nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m0, 1920 const struct sockaddr_in6 *dst, struct rtentry *rt0) 1921 { 1922 struct mbuf *m = m0; 1923 struct rtentry *rt = rt0; 1924 struct sockaddr_in6 *gw6 = NULL; 1925 struct llinfo_nd6 *ln = NULL; 1926 int error = 0; 1927 1928 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr)) 1929 goto sendpkt; 1930 1931 if (nd6_need_cache(ifp) == 0) 1932 goto sendpkt; 1933 1934 /* 1935 * next hop determination. This routine is derived from ether_output. 1936 */ 1937 if (rt) { 1938 if ((rt->rt_flags & RTF_UP) == 0) { 1939 if ((rt0 = rt = rtalloc1(sin6tocsa(dst), 1)) != NULL) { 1940 rt->rt_refcnt--; 1941 if (rt->rt_ifp != ifp) 1942 senderr(EHOSTUNREACH); 1943 } else 1944 senderr(EHOSTUNREACH); 1945 } 1946 1947 if (rt->rt_flags & RTF_GATEWAY) { 1948 gw6 = (struct sockaddr_in6 *)rt->rt_gateway; 1949 1950 /* 1951 * We skip link-layer address resolution and NUD 1952 * if the gateway is not a neighbor from ND point 1953 * of view, regardless of the value of nd_ifinfo.flags. 1954 * The second condition is a bit tricky; we skip 1955 * if the gateway is our own address, which is 1956 * sometimes used to install a route to a p2p link. 1957 */ 1958 if (!nd6_is_addr_neighbor(gw6, ifp) || 1959 in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) { 1960 /* 1961 * We allow this kind of tricky route only 1962 * when the outgoing interface is p2p. 1963 * XXX: we may need a more generic rule here. 1964 */ 1965 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 1966 senderr(EHOSTUNREACH); 1967 1968 goto sendpkt; 1969 } 1970 1971 if (rt->rt_gwroute == NULL) 1972 goto lookup; 1973 if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) { 1974 rtfree(rt); rt = rt0; 1975 lookup: 1976 rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1); 1977 if ((rt = rt->rt_gwroute) == NULL) 1978 senderr(EHOSTUNREACH); 1979 /* the "G" test below also prevents rt == rt0 */ 1980 if ((rt->rt_flags & RTF_GATEWAY) || 1981 (rt->rt_ifp != ifp)) { 1982 rt->rt_refcnt--; 1983 rt0->rt_gwroute = NULL; 1984 senderr(EHOSTUNREACH); 1985 } 1986 } 1987 } 1988 } 1989 1990 /* 1991 * Address resolution or Neighbor Unreachability Detection 1992 * for the next hop. 1993 * At this point, the destination of the packet must be a unicast 1994 * or an anycast address(i.e. not a multicast). 1995 */ 1996 1997 /* Look up the neighbor cache for the nexthop */ 1998 if (rt != NULL && (rt->rt_flags & RTF_LLINFO) != 0) 1999 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2000 else { 2001 /* 2002 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 2003 * the condition below is not very efficient. But we believe 2004 * it is tolerable, because this should be a rare case. 2005 */ 2006 if (nd6_is_addr_neighbor(dst, ifp) && 2007 (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL) 2008 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2009 } 2010 if (ln == NULL || rt == NULL) { 2011 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 && 2012 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { 2013 log(LOG_DEBUG, 2014 "nd6_output: can't allocate llinfo for %s " 2015 "(ln=%p, rt=%p)\n", 2016 ip6_sprintf(&dst->sin6_addr), ln, rt); 2017 senderr(EIO); /* XXX: good error? */ 2018 } 2019 2020 goto sendpkt; /* send anyway */ 2021 } 2022 2023 /* We don't have to do link-layer address resolution on a p2p link. */ 2024 if ((ifp->if_flags & IFF_POINTOPOINT) != 0 && 2025 ln->ln_state < ND6_LLINFO_REACHABLE) { 2026 ln->ln_state = ND6_LLINFO_STALE; 2027 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 2028 } 2029 2030 /* 2031 * The first time we send a packet to a neighbor whose entry is 2032 * STALE, we have to change the state to DELAY and a sets a timer to 2033 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2034 * neighbor unreachability detection on expiration. 2035 * (RFC 2461 7.3.3) 2036 */ 2037 if (ln->ln_state == ND6_LLINFO_STALE) { 2038 ln->ln_asked = 0; 2039 ln->ln_state = ND6_LLINFO_DELAY; 2040 nd6_llinfo_settimer(ln, (long)nd6_delay * hz); 2041 } 2042 2043 /* 2044 * If the neighbor cache entry has a state other than INCOMPLETE 2045 * (i.e. its link-layer address is already resolved), just 2046 * send the packet. 2047 */ 2048 if (ln->ln_state > ND6_LLINFO_INCOMPLETE) 2049 goto sendpkt; 2050 2051 /* 2052 * There is a neighbor cache entry, but no ethernet address 2053 * response yet. Append this latest packet to the end of the 2054 * packet queue in the mbuf, unless the number of the packet 2055 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, 2056 * the oldest packet in the queue will be removed. 2057 */ 2058 if (ln->ln_state == ND6_LLINFO_NOSTATE) 2059 ln->ln_state = ND6_LLINFO_INCOMPLETE; 2060 if (ln->ln_hold) { 2061 struct mbuf *m_hold; 2062 int i; 2063 2064 i = 0; 2065 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold->m_nextpkt) { 2066 i++; 2067 if (m_hold->m_nextpkt == NULL) { 2068 m_hold->m_nextpkt = m; 2069 break; 2070 } 2071 } 2072 while (i >= nd6_maxqueuelen) { 2073 m_hold = ln->ln_hold; 2074 ln->ln_hold = ln->ln_hold->m_nextpkt; 2075 m_freem(m_hold); 2076 i--; 2077 } 2078 } else { 2079 ln->ln_hold = m; 2080 } 2081 2082 /* 2083 * If there has been no NS for the neighbor after entering the 2084 * INCOMPLETE state, send the first solicitation. 2085 */ 2086 if (!ND6_LLINFO_PERMANENT(ln) && ln->ln_asked == 0) { 2087 ln->ln_asked++; 2088 nd6_llinfo_settimer(ln, 2089 (long)ND_IFINFO(ifp)->retrans * hz / 1000); 2090 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 2091 } 2092 return 0; 2093 2094 sendpkt: 2095 /* discard the packet if IPv6 operation is disabled on the interface */ 2096 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 2097 error = ENETDOWN; /* better error? */ 2098 goto bad; 2099 } 2100 2101 #ifdef IPSEC 2102 /* clean ipsec history once it goes out of the node */ 2103 ipsec_delaux(m); 2104 #endif 2105 if ((ifp->if_flags & IFF_LOOPBACK) != 0) 2106 return (*ifp->if_output)(origifp, m, sin6tocsa(dst), rt); 2107 return (*ifp->if_output)(ifp, m, sin6tocsa(dst), rt); 2108 2109 bad: 2110 if (m != NULL) 2111 m_freem(m); 2112 return error; 2113 } 2114 #undef senderr 2115 2116 int 2117 nd6_need_cache(struct ifnet *ifp) 2118 { 2119 /* 2120 * XXX: we currently do not make neighbor cache on any interface 2121 * other than ARCnet, Ethernet, FDDI and GIF. 2122 * 2123 * RFC2893 says: 2124 * - unidirectional tunnels needs no ND 2125 */ 2126 switch (ifp->if_type) { 2127 case IFT_ARCNET: 2128 case IFT_ETHER: 2129 case IFT_FDDI: 2130 case IFT_IEEE1394: 2131 case IFT_CARP: 2132 case IFT_GIF: /* XXX need more cases? */ 2133 case IFT_PPP: 2134 case IFT_TUNNEL: 2135 return 1; 2136 default: 2137 return 0; 2138 } 2139 } 2140 2141 int 2142 nd6_storelladdr(const struct ifnet *ifp, const struct rtentry *rt, 2143 struct mbuf *m, const struct sockaddr *dst, uint8_t *lldst, 2144 size_t dstsize) 2145 { 2146 const struct sockaddr_dl *sdl; 2147 2148 if (m->m_flags & M_MCAST) { 2149 switch (ifp->if_type) { 2150 case IFT_ETHER: 2151 case IFT_FDDI: 2152 ETHER_MAP_IPV6_MULTICAST(&satocsin6(dst)->sin6_addr, 2153 lldst); 2154 return 1; 2155 case IFT_IEEE1394: 2156 memcpy(lldst, ifp->if_broadcastaddr, 2157 MIN(dstsize, ifp->if_addrlen)); 2158 return 1; 2159 case IFT_ARCNET: 2160 *lldst = 0; 2161 return 1; 2162 default: 2163 m_freem(m); 2164 return 0; 2165 } 2166 } 2167 2168 if (rt == NULL) { 2169 /* this could happen, if we could not allocate memory */ 2170 m_freem(m); 2171 return 0; 2172 } 2173 if (rt->rt_gateway->sa_family != AF_LINK) { 2174 printf("%s: something odd happens\n", __func__); 2175 m_freem(m); 2176 return 0; 2177 } 2178 sdl = satocsdl(rt->rt_gateway); 2179 if (sdl->sdl_alen == 0 || sdl->sdl_alen > dstsize) { 2180 /* this should be impossible, but we bark here for debugging */ 2181 printf("%s: sdl_alen == 0, dst=%s, if=%s\n", __func__, 2182 ip6_sprintf(&satocsin6(dst)->sin6_addr), if_name(ifp)); 2183 m_freem(m); 2184 return 0; 2185 } 2186 2187 memcpy(lldst, CLLADDR(sdl), MIN(dstsize, sdl->sdl_alen)); 2188 return 1; 2189 } 2190 2191 static void 2192 clear_llinfo_pqueue(struct llinfo_nd6 *ln) 2193 { 2194 struct mbuf *m_hold, *m_hold_next; 2195 2196 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold_next) { 2197 m_hold_next = m_hold->m_nextpkt; 2198 m_hold->m_nextpkt = NULL; 2199 m_freem(m_hold); 2200 } 2201 2202 ln->ln_hold = NULL; 2203 return; 2204 } 2205 2206 int 2207 nd6_sysctl( 2208 int name, 2209 void *oldp, /* syscall arg, need copyout */ 2210 size_t *oldlenp, 2211 void *newp, /* syscall arg, need copyin */ 2212 size_t newlen 2213 ) 2214 { 2215 void *p; 2216 size_t ol; 2217 int error; 2218 2219 error = 0; 2220 2221 if (newp) 2222 return EPERM; 2223 if (oldp && !oldlenp) 2224 return EINVAL; 2225 ol = oldlenp ? *oldlenp : 0; 2226 2227 if (oldp) { 2228 p = malloc(*oldlenp, M_TEMP, M_WAITOK); 2229 if (p == NULL) 2230 return ENOMEM; 2231 } else 2232 p = NULL; 2233 switch (name) { 2234 case ICMPV6CTL_ND6_DRLIST: 2235 error = fill_drlist(p, oldlenp, ol); 2236 if (!error && p != NULL && oldp != NULL) 2237 error = copyout(p, oldp, *oldlenp); 2238 break; 2239 2240 case ICMPV6CTL_ND6_PRLIST: 2241 error = fill_prlist(p, oldlenp, ol); 2242 if (!error && p != NULL && oldp != NULL) 2243 error = copyout(p, oldp, *oldlenp); 2244 break; 2245 2246 case ICMPV6CTL_ND6_MAXQLEN: 2247 break; 2248 2249 default: 2250 error = ENOPROTOOPT; 2251 break; 2252 } 2253 if (p) 2254 free(p, M_TEMP); 2255 2256 return error; 2257 } 2258 2259 static int 2260 fill_drlist(void *oldp, size_t *oldlenp, size_t 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 *)((char *)oldp + *oldlenp); 2272 } 2273 l = 0; 2274 2275 TAILQ_FOREACH(dr, &nd_defrouter, dr_entry) { 2276 2277 if (oldp && d + 1 <= de) { 2278 memset(d, 0, sizeof(*d)); 2279 sockaddr_in6_init(&d->rtaddr, &dr->rtaddr, 0, 0, 0); 2280 if (sa6_recoverscope(&d->rtaddr)) { 2281 log(LOG_ERR, 2282 "scope error in router list (%s)\n", 2283 ip6_sprintf(&d->rtaddr.sin6_addr)); 2284 /* XXX: press on... */ 2285 } 2286 d->flags = dr->flags; 2287 d->rtlifetime = dr->rtlifetime; 2288 d->expire = dr->expire; 2289 d->if_index = dr->ifp->if_index; 2290 } 2291 2292 l += sizeof(*d); 2293 if (d) 2294 d++; 2295 } 2296 2297 if (oldp) { 2298 if (l > ol) 2299 error = ENOMEM; 2300 } 2301 if (oldlenp) 2302 *oldlenp = l; /* (void *)d - (void *)oldp */ 2303 2304 splx(s); 2305 2306 return error; 2307 } 2308 2309 static int 2310 fill_prlist(void *oldp, size_t *oldlenp, size_t ol) 2311 { 2312 int error = 0, s; 2313 struct nd_prefix *pr; 2314 struct in6_prefix *p = NULL; 2315 struct in6_prefix *pe = NULL; 2316 size_t l; 2317 2318 s = splsoftnet(); 2319 2320 if (oldp) { 2321 p = (struct in6_prefix *)oldp; 2322 pe = (struct in6_prefix *)((char *)oldp + *oldlenp); 2323 } 2324 l = 0; 2325 2326 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 2327 u_short advrtrs; 2328 size_t advance; 2329 struct sockaddr_in6 *sin6; 2330 struct sockaddr_in6 *s6; 2331 struct nd_pfxrouter *pfr; 2332 2333 if (oldp && p + 1 <= pe) 2334 { 2335 memset(p, 0, sizeof(*p)); 2336 sin6 = (struct sockaddr_in6 *)(p + 1); 2337 2338 p->prefix = pr->ndpr_prefix; 2339 if (sa6_recoverscope(&p->prefix)) { 2340 log(LOG_ERR, 2341 "scope error in prefix list (%s)\n", 2342 ip6_sprintf(&p->prefix.sin6_addr)); 2343 /* XXX: press on... */ 2344 } 2345 p->raflags = pr->ndpr_raf; 2346 p->prefixlen = pr->ndpr_plen; 2347 p->vltime = pr->ndpr_vltime; 2348 p->pltime = pr->ndpr_pltime; 2349 p->if_index = pr->ndpr_ifp->if_index; 2350 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2351 p->expire = 0; 2352 else { 2353 time_t maxexpire; 2354 2355 /* XXX: we assume time_t is signed. */ 2356 maxexpire = (-1) & 2357 ~((time_t)1 << 2358 ((sizeof(maxexpire) * 8) - 1)); 2359 if (pr->ndpr_vltime < 2360 maxexpire - pr->ndpr_lastupdate) { 2361 p->expire = pr->ndpr_lastupdate + 2362 pr->ndpr_vltime; 2363 } else 2364 p->expire = maxexpire; 2365 } 2366 p->refcnt = pr->ndpr_refcnt; 2367 p->flags = pr->ndpr_stateflags; 2368 p->origin = PR_ORIG_RA; 2369 advrtrs = 0; 2370 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) { 2371 if ((void *)&sin6[advrtrs + 1] > (void *)pe) { 2372 advrtrs++; 2373 continue; 2374 } 2375 s6 = &sin6[advrtrs]; 2376 sockaddr_in6_init(s6, &pfr->router->rtaddr, 2377 0, 0, 0); 2378 if (sa6_recoverscope(s6)) { 2379 log(LOG_ERR, 2380 "scope error in " 2381 "prefix list (%s)\n", 2382 ip6_sprintf(&pfr->router->rtaddr)); 2383 } 2384 advrtrs++; 2385 } 2386 p->advrtrs = advrtrs; 2387 } 2388 else { 2389 advrtrs = 0; 2390 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) 2391 advrtrs++; 2392 } 2393 2394 advance = sizeof(*p) + sizeof(*sin6) * advrtrs; 2395 l += advance; 2396 if (p) 2397 p = (struct in6_prefix *)((char *)p + advance); 2398 } 2399 2400 if (oldp) { 2401 *oldlenp = l; /* (void *)d - (void *)oldp */ 2402 if (l > ol) 2403 error = ENOMEM; 2404 } else 2405 *oldlenp = l; 2406 2407 splx(s); 2408 2409 return error; 2410 } 2411