1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_mac.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/callout.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/socket.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/syslog.h> 51 #include <sys/queue.h> 52 #include <sys/sysctl.h> 53 54 #include <net/if.h> 55 #include <net/if_arc.h> 56 #include <net/if_dl.h> 57 #include <net/if_types.h> 58 #include <net/iso88025.h> 59 #include <net/fddi.h> 60 #include <net/route.h> 61 62 #include <netinet/in.h> 63 #include <netinet/if_ether.h> 64 #include <netinet6/in6_var.h> 65 #include <netinet/ip6.h> 66 #include <netinet6/ip6_var.h> 67 #include <netinet6/scope6_var.h> 68 #include <netinet6/nd6.h> 69 #include <netinet/icmp6.h> 70 71 #include <sys/limits.h> 72 #include <sys/vimage.h> 73 74 #include <security/mac/mac_framework.h> 75 76 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ 77 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ 78 79 #define SIN6(s) ((struct sockaddr_in6 *)s) 80 #define SDL(s) ((struct sockaddr_dl *)s) 81 82 /* timer values */ 83 int nd6_prune = 1; /* walk list every 1 seconds */ 84 int nd6_delay = 5; /* delay first probe time 5 second */ 85 int nd6_umaxtries = 3; /* maximum unicast query */ 86 int nd6_mmaxtries = 3; /* maximum multicast query */ 87 int nd6_useloopback = 1; /* use loopback interface for local traffic */ 88 int nd6_gctimer = (60 * 60 * 24); /* 1 day: garbage collection timer */ 89 90 /* preventing too many loops in ND option parsing */ 91 int nd6_maxndopt = 10; /* max # of ND options allowed */ 92 93 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */ 94 int nd6_maxqueuelen = 1; /* max # of packets cached in unresolved ND entries */ 95 96 #ifdef ND6_DEBUG 97 int nd6_debug = 1; 98 #else 99 int nd6_debug = 0; 100 #endif 101 102 /* for debugging? */ 103 static int nd6_inuse, nd6_allocated; 104 105 struct llinfo_nd6 llinfo_nd6 = {&llinfo_nd6, &llinfo_nd6}; 106 struct nd_drhead nd_defrouter; 107 struct nd_prhead nd_prefix = { 0 }; 108 109 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL; 110 static struct sockaddr_in6 all1_sa; 111 112 static int nd6_is_new_addr_neighbor __P((struct sockaddr_in6 *, 113 struct ifnet *)); 114 static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *); 115 static void nd6_slowtimo(void *); 116 static int regen_tmpaddr(struct in6_ifaddr *); 117 static struct llinfo_nd6 *nd6_free(struct rtentry *, int); 118 static void nd6_llinfo_timer(void *); 119 static void clear_llinfo_pqueue(struct llinfo_nd6 *); 120 121 struct callout nd6_slowtimo_ch; 122 struct callout nd6_timer_ch; 123 extern struct callout in6_tmpaddrtimer_ch; 124 125 void 126 nd6_init(void) 127 { 128 INIT_VNET_INET6(curvnet); 129 static int nd6_init_done = 0; 130 int i; 131 132 if (nd6_init_done) { 133 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n"); 134 return; 135 } 136 137 all1_sa.sin6_family = AF_INET6; 138 all1_sa.sin6_len = sizeof(struct sockaddr_in6); 139 for (i = 0; i < sizeof(all1_sa.sin6_addr); i++) 140 all1_sa.sin6_addr.s6_addr[i] = 0xff; 141 142 /* initialization of the default router list */ 143 TAILQ_INIT(&V_nd_defrouter); 144 /* start timer */ 145 callout_init(&V_nd6_slowtimo_ch, 0); 146 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 147 nd6_slowtimo, NULL); 148 149 nd6_init_done = 1; 150 151 } 152 153 struct nd_ifinfo * 154 nd6_ifattach(struct ifnet *ifp) 155 { 156 struct nd_ifinfo *nd; 157 158 nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK); 159 bzero(nd, sizeof(*nd)); 160 161 nd->initialized = 1; 162 163 nd->chlim = IPV6_DEFHLIM; 164 nd->basereachable = REACHABLE_TIME; 165 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 166 nd->retrans = RETRANS_TIMER; 167 /* 168 * Note that the default value of ip6_accept_rtadv is 0, which means 169 * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV 170 * here. 171 */ 172 nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV); 173 174 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 175 nd6_setmtu0(ifp, nd); 176 177 return nd; 178 } 179 180 void 181 nd6_ifdetach(struct nd_ifinfo *nd) 182 { 183 184 free(nd, M_IP6NDP); 185 } 186 187 /* 188 * Reset ND level link MTU. This function is called when the physical MTU 189 * changes, which means we might have to adjust the ND level MTU. 190 */ 191 void 192 nd6_setmtu(struct ifnet *ifp) 193 { 194 195 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 196 } 197 198 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */ 199 void 200 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi) 201 { 202 INIT_VNET_INET6(ifp->if_vnet); 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); /* RFC2467 */ 213 break; 214 case IFT_ISO88025: 215 ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu); 216 break; 217 default: 218 ndi->maxmtu = ifp->if_mtu; 219 break; 220 } 221 222 /* 223 * Decreasing the interface MTU under IPV6 minimum MTU may cause 224 * undesirable situation. We thus notify the operator of the change 225 * explicitly. The check for omaxmtu is necessary to restrict the 226 * log to the case of changing the MTU, not initializing it. 227 */ 228 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 229 log(LOG_NOTICE, "nd6_setmtu0: " 230 "new link MTU on %s (%lu) is too small for IPv6\n", 231 if_name(ifp), (unsigned long)ndi->maxmtu); 232 } 233 234 if (ndi->maxmtu > V_in6_maxmtu) 235 in6_setmaxmtu(); /* check all interfaces just in case */ 236 237 #undef MIN 238 } 239 240 void 241 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts) 242 { 243 244 bzero(ndopts, sizeof(*ndopts)); 245 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 246 ndopts->nd_opts_last 247 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 248 249 if (icmp6len == 0) { 250 ndopts->nd_opts_done = 1; 251 ndopts->nd_opts_search = NULL; 252 } 253 } 254 255 /* 256 * Take one ND option. 257 */ 258 struct nd_opt_hdr * 259 nd6_option(union nd_opts *ndopts) 260 { 261 struct nd_opt_hdr *nd_opt; 262 int olen; 263 264 if (ndopts == NULL) 265 panic("ndopts == NULL in nd6_option"); 266 if (ndopts->nd_opts_last == NULL) 267 panic("uninitialized ndopts in nd6_option"); 268 if (ndopts->nd_opts_search == NULL) 269 return NULL; 270 if (ndopts->nd_opts_done) 271 return NULL; 272 273 nd_opt = ndopts->nd_opts_search; 274 275 /* make sure nd_opt_len is inside the buffer */ 276 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { 277 bzero(ndopts, sizeof(*ndopts)); 278 return NULL; 279 } 280 281 olen = nd_opt->nd_opt_len << 3; 282 if (olen == 0) { 283 /* 284 * Message validation requires that all included 285 * options have a length that is greater than zero. 286 */ 287 bzero(ndopts, sizeof(*ndopts)); 288 return NULL; 289 } 290 291 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); 292 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 293 /* option overruns the end of buffer, invalid */ 294 bzero(ndopts, sizeof(*ndopts)); 295 return NULL; 296 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 297 /* reached the end of options chain */ 298 ndopts->nd_opts_done = 1; 299 ndopts->nd_opts_search = NULL; 300 } 301 return nd_opt; 302 } 303 304 /* 305 * Parse multiple ND options. 306 * This function is much easier to use, for ND routines that do not need 307 * multiple options of the same type. 308 */ 309 int 310 nd6_options(union nd_opts *ndopts) 311 { 312 INIT_VNET_INET6(curvnet); 313 struct nd_opt_hdr *nd_opt; 314 int i = 0; 315 316 if (ndopts == NULL) 317 panic("ndopts == NULL in nd6_options"); 318 if (ndopts->nd_opts_last == NULL) 319 panic("uninitialized ndopts in nd6_options"); 320 if (ndopts->nd_opts_search == NULL) 321 return 0; 322 323 while (1) { 324 nd_opt = nd6_option(ndopts); 325 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 326 /* 327 * Message validation requires that all included 328 * options have a length that is greater than zero. 329 */ 330 V_icmp6stat.icp6s_nd_badopt++; 331 bzero(ndopts, sizeof(*ndopts)); 332 return -1; 333 } 334 335 if (nd_opt == NULL) 336 goto skip1; 337 338 switch (nd_opt->nd_opt_type) { 339 case ND_OPT_SOURCE_LINKADDR: 340 case ND_OPT_TARGET_LINKADDR: 341 case ND_OPT_MTU: 342 case ND_OPT_REDIRECTED_HEADER: 343 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 344 nd6log((LOG_INFO, 345 "duplicated ND6 option found (type=%d)\n", 346 nd_opt->nd_opt_type)); 347 /* XXX bark? */ 348 } else { 349 ndopts->nd_opt_array[nd_opt->nd_opt_type] 350 = nd_opt; 351 } 352 break; 353 case ND_OPT_PREFIX_INFORMATION: 354 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 355 ndopts->nd_opt_array[nd_opt->nd_opt_type] 356 = nd_opt; 357 } 358 ndopts->nd_opts_pi_end = 359 (struct nd_opt_prefix_info *)nd_opt; 360 break; 361 default: 362 /* 363 * Unknown options must be silently ignored, 364 * to accomodate future extension to the protocol. 365 */ 366 nd6log((LOG_DEBUG, 367 "nd6_options: unsupported option %d - " 368 "option ignored\n", nd_opt->nd_opt_type)); 369 } 370 371 skip1: 372 i++; 373 if (i > V_nd6_maxndopt) { 374 V_icmp6stat.icp6s_nd_toomanyopt++; 375 nd6log((LOG_INFO, "too many loop in nd opt\n")); 376 break; 377 } 378 379 if (ndopts->nd_opts_done) 380 break; 381 } 382 383 return 0; 384 } 385 386 /* 387 * ND6 timer routine to handle ND6 entries 388 */ 389 void 390 nd6_llinfo_settimer(struct llinfo_nd6 *ln, long tick) 391 { 392 if (tick < 0) { 393 ln->ln_expire = 0; 394 ln->ln_ntick = 0; 395 callout_stop(&ln->ln_timer_ch); 396 } else { 397 ln->ln_expire = time_second + tick / hz; 398 if (tick > INT_MAX) { 399 ln->ln_ntick = tick - INT_MAX; 400 callout_reset(&ln->ln_timer_ch, INT_MAX, 401 nd6_llinfo_timer, ln); 402 } else { 403 ln->ln_ntick = 0; 404 callout_reset(&ln->ln_timer_ch, tick, 405 nd6_llinfo_timer, ln); 406 } 407 } 408 } 409 410 static void 411 nd6_llinfo_timer(void *arg) 412 { 413 struct llinfo_nd6 *ln; 414 struct rtentry *rt; 415 struct in6_addr *dst; 416 struct ifnet *ifp; 417 struct nd_ifinfo *ndi = NULL; 418 419 ln = (struct llinfo_nd6 *)arg; 420 421 if (ln->ln_ntick > 0) { 422 if (ln->ln_ntick > INT_MAX) { 423 ln->ln_ntick -= INT_MAX; 424 nd6_llinfo_settimer(ln, INT_MAX); 425 } else { 426 ln->ln_ntick = 0; 427 nd6_llinfo_settimer(ln, ln->ln_ntick); 428 } 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); 437 438 CURVNET_SET(ifp->if_vnet); 439 INIT_VNET_INET6(curvnet); 440 441 /* sanity check */ 442 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln) 443 panic("rt_llinfo(%p) is not equal to ln(%p)", 444 rt->rt_llinfo, ln); 445 if (rt_key(rt) == NULL) 446 panic("rt key is NULL in nd6_timer(ln=%p)", ln); 447 448 dst = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 449 450 switch (ln->ln_state) { 451 case ND6_LLINFO_INCOMPLETE: 452 if (ln->ln_asked < V_nd6_mmaxtries) { 453 ln->ln_asked++; 454 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 455 nd6_ns_output(ifp, NULL, dst, ln, 0); 456 } else { 457 struct mbuf *m = ln->ln_hold; 458 if (m) { 459 struct mbuf *m0; 460 461 /* 462 * assuming every packet in ln_hold has the 463 * same IP header 464 */ 465 m0 = m->m_nextpkt; 466 m->m_nextpkt = NULL; 467 icmp6_error2(m, ICMP6_DST_UNREACH, 468 ICMP6_DST_UNREACH_ADDR, 0, rt->rt_ifp); 469 470 ln->ln_hold = m0; 471 clear_llinfo_pqueue(ln); 472 } 473 if (rt && rt->rt_llinfo) 474 (void)nd6_free(rt, 0); 475 ln = NULL; 476 } 477 break; 478 case ND6_LLINFO_REACHABLE: 479 if (!ND6_LLINFO_PERMANENT(ln)) { 480 ln->ln_state = ND6_LLINFO_STALE; 481 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 482 } 483 break; 484 485 case ND6_LLINFO_STALE: 486 /* Garbage Collection(RFC 2461 5.3) */ 487 if (!ND6_LLINFO_PERMANENT(ln)) { 488 if (rt && rt->rt_llinfo) 489 (void)nd6_free(rt, 1); 490 ln = NULL; 491 } 492 break; 493 494 case ND6_LLINFO_DELAY: 495 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 496 /* We need NUD */ 497 ln->ln_asked = 1; 498 ln->ln_state = ND6_LLINFO_PROBE; 499 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 500 nd6_ns_output(ifp, dst, dst, ln, 0); 501 } else { 502 ln->ln_state = ND6_LLINFO_STALE; /* XXX */ 503 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 504 } 505 break; 506 case ND6_LLINFO_PROBE: 507 if (ln->ln_asked < V_nd6_umaxtries) { 508 ln->ln_asked++; 509 nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000); 510 nd6_ns_output(ifp, dst, dst, ln, 0); 511 } else if (rt->rt_ifa != NULL && 512 rt->rt_ifa->ifa_addr->sa_family == AF_INET6 && 513 (((struct in6_ifaddr *)rt->rt_ifa)->ia_flags & IFA_ROUTE)) { 514 /* 515 * This is an unreachable neighbor whose address is 516 * specified as the destination of a p2p interface 517 * (see in6_ifinit()). We should not free the entry 518 * since this is sort of a "static" entry generated 519 * via interface address configuration. 520 */ 521 ln->ln_asked = 0; 522 ln->ln_expire = 0; /* make it permanent */ 523 ln->ln_state = ND6_LLINFO_STALE; 524 } else { 525 if (rt && rt->rt_llinfo) 526 (void)nd6_free(rt, 0); 527 ln = NULL; 528 } 529 break; 530 } 531 CURVNET_RESTORE(); 532 } 533 534 535 /* 536 * ND6 timer routine to expire default route list and prefix list 537 */ 538 void 539 nd6_timer(void *arg) 540 { 541 CURVNET_SET_QUIET((struct vnet *) arg); 542 INIT_VNET_INET6((struct vnet *) arg); 543 int s; 544 struct nd_defrouter *dr; 545 struct nd_prefix *pr; 546 struct in6_ifaddr *ia6, *nia6; 547 struct in6_addrlifetime *lt6; 548 549 callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz, 550 nd6_timer, NULL); 551 552 /* expire default router list */ 553 s = splnet(); 554 dr = TAILQ_FIRST(&V_nd_defrouter); 555 while (dr) { 556 if (dr->expire && dr->expire < time_second) { 557 struct nd_defrouter *t; 558 t = TAILQ_NEXT(dr, dr_entry); 559 defrtrlist_del(dr); 560 dr = t; 561 } else { 562 dr = TAILQ_NEXT(dr, dr_entry); 563 } 564 } 565 566 /* 567 * expire interface addresses. 568 * in the past the loop was inside prefix expiry processing. 569 * However, from a stricter speci-confrmance standpoint, we should 570 * rather separate address lifetimes and prefix lifetimes. 571 */ 572 addrloop: 573 for (ia6 = V_in6_ifaddr; ia6; ia6 = nia6) { 574 nia6 = ia6->ia_next; 575 /* check address lifetime */ 576 lt6 = &ia6->ia6_lifetime; 577 if (IFA6_IS_INVALID(ia6)) { 578 int regen = 0; 579 580 /* 581 * If the expiring address is temporary, try 582 * regenerating a new one. This would be useful when 583 * we suspended a laptop PC, then turned it on after a 584 * period that could invalidate all temporary 585 * addresses. Although we may have to restart the 586 * loop (see below), it must be after purging the 587 * address. Otherwise, we'd see an infinite loop of 588 * regeneration. 589 */ 590 if (V_ip6_use_tempaddr && 591 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 592 if (regen_tmpaddr(ia6) == 0) 593 regen = 1; 594 } 595 596 in6_purgeaddr(&ia6->ia_ifa); 597 598 if (regen) 599 goto addrloop; /* XXX: see below */ 600 } else if (IFA6_IS_DEPRECATED(ia6)) { 601 int oldflags = ia6->ia6_flags; 602 603 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 604 605 /* 606 * If a temporary address has just become deprecated, 607 * regenerate a new one if possible. 608 */ 609 if (V_ip6_use_tempaddr && 610 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 611 (oldflags & IN6_IFF_DEPRECATED) == 0) { 612 613 if (regen_tmpaddr(ia6) == 0) { 614 /* 615 * A new temporary address is 616 * generated. 617 * XXX: this means the address chain 618 * has changed while we are still in 619 * the loop. Although the change 620 * would not cause disaster (because 621 * it's not a deletion, but an 622 * addition,) we'd rather restart the 623 * loop just for safety. Or does this 624 * significantly reduce performance?? 625 */ 626 goto addrloop; 627 } 628 } 629 } else { 630 /* 631 * A new RA might have made a deprecated address 632 * preferred. 633 */ 634 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 635 } 636 } 637 638 /* expire prefix list */ 639 pr = V_nd_prefix.lh_first; 640 while (pr) { 641 /* 642 * check prefix lifetime. 643 * since pltime is just for autoconf, pltime processing for 644 * prefix is not necessary. 645 */ 646 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && 647 time_second - pr->ndpr_lastupdate > pr->ndpr_vltime) { 648 struct nd_prefix *t; 649 t = pr->ndpr_next; 650 651 /* 652 * address expiration and prefix expiration are 653 * separate. NEVER perform in6_purgeaddr here. 654 */ 655 656 prelist_remove(pr); 657 pr = t; 658 } else 659 pr = pr->ndpr_next; 660 } 661 splx(s); 662 CURVNET_RESTORE(); 663 } 664 665 /* 666 * ia6 - deprecated/invalidated temporary address 667 */ 668 static int 669 regen_tmpaddr(struct in6_ifaddr *ia6) 670 { 671 struct ifaddr *ifa; 672 struct ifnet *ifp; 673 struct in6_ifaddr *public_ifa6 = NULL; 674 675 ifp = ia6->ia_ifa.ifa_ifp; 676 for (ifa = ifp->if_addrlist.tqh_first; ifa; 677 ifa = ifa->ifa_list.tqe_next) { 678 struct in6_ifaddr *it6; 679 680 if (ifa->ifa_addr->sa_family != AF_INET6) 681 continue; 682 683 it6 = (struct in6_ifaddr *)ifa; 684 685 /* ignore no autoconf addresses. */ 686 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 687 continue; 688 689 /* ignore autoconf addresses with different prefixes. */ 690 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 691 continue; 692 693 /* 694 * Now we are looking at an autoconf address with the same 695 * prefix as ours. If the address is temporary and is still 696 * preferred, do not create another one. It would be rare, but 697 * could happen, for example, when we resume a laptop PC after 698 * a long period. 699 */ 700 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 701 !IFA6_IS_DEPRECATED(it6)) { 702 public_ifa6 = NULL; 703 break; 704 } 705 706 /* 707 * This is a public autoconf address that has the same prefix 708 * as ours. If it is preferred, keep it. We can't break the 709 * loop here, because there may be a still-preferred temporary 710 * address with the prefix. 711 */ 712 if (!IFA6_IS_DEPRECATED(it6)) 713 public_ifa6 = it6; 714 } 715 716 if (public_ifa6 != NULL) { 717 int e; 718 719 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 720 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 721 " tmp addr,errno=%d\n", e); 722 return (-1); 723 } 724 return (0); 725 } 726 727 return (-1); 728 } 729 730 /* 731 * Nuke neighbor cache/prefix/default router management table, right before 732 * ifp goes away. 733 */ 734 void 735 nd6_purge(struct ifnet *ifp) 736 { 737 INIT_VNET_INET6(ifp->if_vnet); 738 struct llinfo_nd6 *ln, *nln; 739 struct nd_defrouter *dr, *ndr; 740 struct nd_prefix *pr, *npr; 741 742 /* 743 * Nuke default router list entries toward ifp. 744 * We defer removal of default router list entries that is installed 745 * in the routing table, in order to keep additional side effects as 746 * small as possible. 747 */ 748 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; dr = ndr) { 749 ndr = TAILQ_NEXT(dr, dr_entry); 750 if (dr->installed) 751 continue; 752 753 if (dr->ifp == ifp) 754 defrtrlist_del(dr); 755 } 756 757 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; dr = ndr) { 758 ndr = TAILQ_NEXT(dr, dr_entry); 759 if (!dr->installed) 760 continue; 761 762 if (dr->ifp == ifp) 763 defrtrlist_del(dr); 764 } 765 766 /* Nuke prefix list entries toward ifp */ 767 for (pr = V_nd_prefix.lh_first; pr; pr = npr) { 768 npr = pr->ndpr_next; 769 if (pr->ndpr_ifp == ifp) { 770 /* 771 * Because if_detach() does *not* release prefixes 772 * while purging addresses the reference count will 773 * still be above zero. We therefore reset it to 774 * make sure that the prefix really gets purged. 775 */ 776 pr->ndpr_refcnt = 0; 777 778 /* 779 * Previously, pr->ndpr_addr is removed as well, 780 * but I strongly believe we don't have to do it. 781 * nd6_purge() is only called from in6_ifdetach(), 782 * which removes all the associated interface addresses 783 * by itself. 784 * (jinmei@kame.net 20010129) 785 */ 786 prelist_remove(pr); 787 } 788 } 789 790 /* cancel default outgoing interface setting */ 791 if (V_nd6_defifindex == ifp->if_index) 792 nd6_setdefaultiface(0); 793 794 if (!V_ip6_forwarding && V_ip6_accept_rtadv) { /* XXX: too restrictive? */ 795 /* refresh default router list */ 796 defrouter_select(); 797 } 798 799 /* 800 * Nuke neighbor cache entries for the ifp. 801 * Note that rt->rt_ifp may not be the same as ifp, 802 * due to KAME goto ours hack. See RTM_RESOLVE case in 803 * nd6_rtrequest(), and ip6_input(). 804 */ 805 ln = V_llinfo_nd6.ln_next; 806 while (ln && ln != &V_llinfo_nd6) { 807 struct rtentry *rt; 808 struct sockaddr_dl *sdl; 809 810 nln = ln->ln_next; 811 rt = ln->ln_rt; 812 if (rt && rt->rt_gateway && 813 rt->rt_gateway->sa_family == AF_LINK) { 814 sdl = (struct sockaddr_dl *)rt->rt_gateway; 815 if (sdl->sdl_index == ifp->if_index) 816 nln = nd6_free(rt, 0); 817 } 818 ln = nln; 819 } 820 } 821 822 struct rtentry * 823 nd6_lookup(struct in6_addr *addr6, int create, struct ifnet *ifp) 824 { 825 INIT_VNET_INET6(curvnet); 826 struct rtentry *rt; 827 struct sockaddr_in6 sin6; 828 char ip6buf[INET6_ADDRSTRLEN]; 829 830 bzero(&sin6, sizeof(sin6)); 831 sin6.sin6_len = sizeof(struct sockaddr_in6); 832 sin6.sin6_family = AF_INET6; 833 sin6.sin6_addr = *addr6; 834 rt = rtalloc1((struct sockaddr *)&sin6, create, 0UL); 835 if (rt) { 836 if ((rt->rt_flags & RTF_LLINFO) == 0 && create) { 837 /* 838 * This is the case for the default route. 839 * If we want to create a neighbor cache for the 840 * address, we should free the route for the 841 * destination and allocate an interface route. 842 */ 843 RTFREE_LOCKED(rt); 844 rt = NULL; 845 } 846 } 847 if (rt == NULL) { 848 if (create && ifp) { 849 int e; 850 851 /* 852 * If no route is available and create is set, 853 * we allocate a host route for the destination 854 * and treat it like an interface route. 855 * This hack is necessary for a neighbor which can't 856 * be covered by our own prefix. 857 */ 858 struct ifaddr *ifa = 859 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp); 860 if (ifa == NULL) 861 return (NULL); 862 863 /* 864 * Create a new route. RTF_LLINFO is necessary 865 * to create a Neighbor Cache entry for the 866 * destination in nd6_rtrequest which will be 867 * called in rtrequest via ifa->ifa_rtrequest. 868 */ 869 if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6, 870 ifa->ifa_addr, (struct sockaddr *)&all1_sa, 871 (ifa->ifa_flags | RTF_HOST | RTF_LLINFO) & 872 ~RTF_CLONING, &rt)) != 0) { 873 log(LOG_ERR, 874 "nd6_lookup: failed to add route for a " 875 "neighbor(%s), errno=%d\n", 876 ip6_sprintf(ip6buf, addr6), e); 877 } 878 if (rt == NULL) 879 return (NULL); 880 RT_LOCK(rt); 881 if (rt->rt_llinfo) { 882 struct llinfo_nd6 *ln = 883 (struct llinfo_nd6 *)rt->rt_llinfo; 884 ln->ln_state = ND6_LLINFO_NOSTATE; 885 } 886 } else 887 return (NULL); 888 } 889 RT_LOCK_ASSERT(rt); 890 RT_REMREF(rt); 891 /* 892 * Validation for the entry. 893 * Note that the check for rt_llinfo is necessary because a cloned 894 * route from a parent route that has the L flag (e.g. the default 895 * route to a p2p interface) may have the flag, too, while the 896 * destination is not actually a neighbor. 897 * XXX: we can't use rt->rt_ifp to check for the interface, since 898 * it might be the loopback interface if the entry is for our 899 * own address on a non-loopback interface. Instead, we should 900 * use rt->rt_ifa->ifa_ifp, which would specify the REAL 901 * interface. 902 * Note also that ifa_ifp and ifp may differ when we connect two 903 * interfaces to a same link, install a link prefix to an interface, 904 * and try to install a neighbor cache on an interface that does not 905 * have a route to the prefix. 906 */ 907 if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 || 908 rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL || 909 (ifp && rt->rt_ifa->ifa_ifp != ifp)) { 910 if (create) { 911 nd6log((LOG_DEBUG, 912 "nd6_lookup: failed to lookup %s (if = %s)\n", 913 ip6_sprintf(ip6buf, addr6), 914 ifp ? if_name(ifp) : "unspec")); 915 } 916 RT_UNLOCK(rt); 917 return (NULL); 918 } 919 RT_UNLOCK(rt); /* XXX not ready to return rt locked */ 920 return (rt); 921 } 922 923 /* 924 * Test whether a given IPv6 address is a neighbor or not, ignoring 925 * the actual neighbor cache. The neighbor cache is ignored in order 926 * to not reenter the routing code from within itself. 927 */ 928 static int 929 nd6_is_new_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp) 930 { 931 INIT_VNET_INET6(ifp->if_vnet); 932 struct nd_prefix *pr; 933 struct ifaddr *dstaddr; 934 935 /* 936 * A link-local address is always a neighbor. 937 * XXX: a link does not necessarily specify a single interface. 938 */ 939 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 940 struct sockaddr_in6 sin6_copy; 941 u_int32_t zone; 942 943 /* 944 * We need sin6_copy since sa6_recoverscope() may modify the 945 * content (XXX). 946 */ 947 sin6_copy = *addr; 948 if (sa6_recoverscope(&sin6_copy)) 949 return (0); /* XXX: should be impossible */ 950 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 951 return (0); 952 if (sin6_copy.sin6_scope_id == zone) 953 return (1); 954 else 955 return (0); 956 } 957 958 /* 959 * If the address matches one of our addresses, 960 * it should be a neighbor. 961 * If the address matches one of our on-link prefixes, it should be a 962 * neighbor. 963 */ 964 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 965 if (pr->ndpr_ifp != ifp) 966 continue; 967 968 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) 969 continue; 970 971 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 972 &addr->sin6_addr, &pr->ndpr_mask)) 973 return (1); 974 } 975 976 /* 977 * If the address is assigned on the node of the other side of 978 * a p2p interface, the address should be a neighbor. 979 */ 980 dstaddr = ifa_ifwithdstaddr((struct sockaddr *)addr); 981 if ((dstaddr != NULL) && (dstaddr->ifa_ifp == ifp)) 982 return (1); 983 984 /* 985 * If the default router list is empty, all addresses are regarded 986 * as on-link, and thus, as a neighbor. 987 * XXX: we restrict the condition to hosts, because routers usually do 988 * not have the "default router list". 989 */ 990 if (!V_ip6_forwarding && TAILQ_FIRST(&V_nd_defrouter) == NULL && 991 V_nd6_defifindex == ifp->if_index) { 992 return (1); 993 } 994 995 return (0); 996 } 997 998 999 /* 1000 * Detect if a given IPv6 address identifies a neighbor on a given link. 1001 * XXX: should take care of the destination of a p2p link? 1002 */ 1003 int 1004 nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp) 1005 { 1006 1007 if (nd6_is_new_addr_neighbor(addr, ifp)) 1008 return (1); 1009 1010 /* 1011 * Even if the address matches none of our addresses, it might be 1012 * in the neighbor cache. 1013 */ 1014 if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL) 1015 return (1); 1016 1017 return (0); 1018 } 1019 1020 /* 1021 * Free an nd6 llinfo entry. 1022 * Since the function would cause significant changes in the kernel, DO NOT 1023 * make it global, unless you have a strong reason for the change, and are sure 1024 * that the change is safe. 1025 */ 1026 static struct llinfo_nd6 * 1027 nd6_free(struct rtentry *rt, int gc) 1028 { 1029 INIT_VNET_INET6(curvnet); 1030 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next; 1031 struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 1032 struct nd_defrouter *dr; 1033 1034 /* 1035 * we used to have pfctlinput(PRC_HOSTDEAD) here. 1036 * even though it is not harmful, it was not really necessary. 1037 */ 1038 1039 /* cancel timer */ 1040 nd6_llinfo_settimer(ln, -1); 1041 1042 if (!V_ip6_forwarding) { 1043 int s; 1044 s = splnet(); 1045 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr, 1046 rt->rt_ifp); 1047 1048 if (dr != NULL && dr->expire && 1049 ln->ln_state == ND6_LLINFO_STALE && gc) { 1050 /* 1051 * If the reason for the deletion is just garbage 1052 * collection, and the neighbor is an active default 1053 * router, do not delete it. Instead, reset the GC 1054 * timer using the router's lifetime. 1055 * Simply deleting the entry would affect default 1056 * router selection, which is not necessarily a good 1057 * thing, especially when we're using router preference 1058 * values. 1059 * XXX: the check for ln_state would be redundant, 1060 * but we intentionally keep it just in case. 1061 */ 1062 if (dr->expire > time_second) 1063 nd6_llinfo_settimer(ln, 1064 (dr->expire - time_second) * hz); 1065 else 1066 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 1067 splx(s); 1068 return (ln->ln_next); 1069 } 1070 1071 if (ln->ln_router || dr) { 1072 /* 1073 * rt6_flush must be called whether or not the neighbor 1074 * is in the Default Router List. 1075 * See a corresponding comment in nd6_na_input(). 1076 */ 1077 rt6_flush(&in6, rt->rt_ifp); 1078 } 1079 1080 if (dr) { 1081 /* 1082 * Unreachablity of a router might affect the default 1083 * router selection and on-link detection of advertised 1084 * prefixes. 1085 */ 1086 1087 /* 1088 * Temporarily fake the state to choose a new default 1089 * router and to perform on-link determination of 1090 * prefixes correctly. 1091 * Below the state will be set correctly, 1092 * or the entry itself will be deleted. 1093 */ 1094 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1095 1096 /* 1097 * Since defrouter_select() does not affect the 1098 * on-link determination and MIP6 needs the check 1099 * before the default router selection, we perform 1100 * the check now. 1101 */ 1102 pfxlist_onlink_check(); 1103 1104 /* 1105 * refresh default router list 1106 */ 1107 defrouter_select(); 1108 } 1109 splx(s); 1110 } 1111 1112 /* 1113 * Before deleting the entry, remember the next entry as the 1114 * return value. We need this because pfxlist_onlink_check() above 1115 * might have freed other entries (particularly the old next entry) as 1116 * a side effect (XXX). 1117 */ 1118 next = ln->ln_next; 1119 1120 /* 1121 * Detach the route from the routing tree and the list of neighbor 1122 * caches, and disable the route entry not to be used in already 1123 * cached routes. 1124 */ 1125 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, 1126 rt_mask(rt), 0, (struct rtentry **)0); 1127 1128 return (next); 1129 } 1130 1131 /* 1132 * Upper-layer reachability hint for Neighbor Unreachability Detection. 1133 * 1134 * XXX cost-effective methods? 1135 */ 1136 void 1137 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force) 1138 { 1139 INIT_VNET_INET6(curvnet); 1140 struct llinfo_nd6 *ln; 1141 1142 /* 1143 * If the caller specified "rt", use that. Otherwise, resolve the 1144 * routing table by supplied "dst6". 1145 */ 1146 if (rt == NULL) { 1147 if (dst6 == NULL) 1148 return; 1149 if ((rt = nd6_lookup(dst6, 0, NULL)) == NULL) 1150 return; 1151 } 1152 1153 if ((rt->rt_flags & RTF_GATEWAY) != 0 || 1154 (rt->rt_flags & RTF_LLINFO) == 0 || 1155 rt->rt_llinfo == NULL || rt->rt_gateway == NULL || 1156 rt->rt_gateway->sa_family != AF_LINK) { 1157 /* This is not a host route. */ 1158 return; 1159 } 1160 1161 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1162 if (ln->ln_state < ND6_LLINFO_REACHABLE) 1163 return; 1164 1165 /* 1166 * if we get upper-layer reachability confirmation many times, 1167 * it is possible we have false information. 1168 */ 1169 if (!force) { 1170 ln->ln_byhint++; 1171 if (ln->ln_byhint > V_nd6_maxnudhint) 1172 return; 1173 } 1174 1175 ln->ln_state = ND6_LLINFO_REACHABLE; 1176 if (!ND6_LLINFO_PERMANENT(ln)) { 1177 nd6_llinfo_settimer(ln, 1178 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 1179 } 1180 } 1181 1182 /* 1183 * info - XXX unused 1184 */ 1185 void 1186 nd6_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info) 1187 { 1188 struct sockaddr *gate = rt->rt_gateway; 1189 struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1190 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 1191 struct ifnet *ifp = rt->rt_ifp; 1192 struct ifaddr *ifa; 1193 INIT_VNET_NET(ifp->if_vnet); 1194 INIT_VNET_INET6(ifp->if_vnet); 1195 1196 RT_LOCK_ASSERT(rt); 1197 1198 if ((rt->rt_flags & RTF_GATEWAY) != 0) 1199 return; 1200 1201 if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) { 1202 /* 1203 * This is probably an interface direct route for a link 1204 * which does not need neighbor caches (e.g. fe80::%lo0/64). 1205 * We do not need special treatment below for such a route. 1206 * Moreover, the RTF_LLINFO flag which would be set below 1207 * would annoy the ndp(8) command. 1208 */ 1209 return; 1210 } 1211 1212 if (req == RTM_RESOLVE && 1213 (nd6_need_cache(ifp) == 0 || /* stf case */ 1214 !nd6_is_new_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), 1215 ifp))) { 1216 /* 1217 * FreeBSD and BSD/OS often make a cloned host route based 1218 * on a less-specific route (e.g. the default route). 1219 * If the less specific route does not have a "gateway" 1220 * (this is the case when the route just goes to a p2p or an 1221 * stf interface), we'll mistakenly make a neighbor cache for 1222 * the host route, and will see strange neighbor solicitation 1223 * for the corresponding destination. In order to avoid the 1224 * confusion, we check if the destination of the route is 1225 * a neighbor in terms of neighbor discovery, and stop the 1226 * process if not. Additionally, we remove the LLINFO flag 1227 * so that ndp(8) will not try to get the neighbor information 1228 * of the destination. 1229 */ 1230 rt->rt_flags &= ~RTF_LLINFO; 1231 return; 1232 } 1233 1234 switch (req) { 1235 case RTM_ADD: 1236 /* 1237 * There is no backward compatibility :) 1238 * 1239 * if ((rt->rt_flags & RTF_HOST) == 0 && 1240 * SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 1241 * rt->rt_flags |= RTF_CLONING; 1242 */ 1243 if ((rt->rt_flags & RTF_CLONING) || 1244 ((rt->rt_flags & RTF_LLINFO) && ln == NULL)) { 1245 /* 1246 * Case 1: This route should come from a route to 1247 * interface (RTF_CLONING case) or the route should be 1248 * treated as on-link but is currently not 1249 * (RTF_LLINFO && ln == NULL case). 1250 */ 1251 rt_setgate(rt, rt_key(rt), 1252 (struct sockaddr *)&null_sdl); 1253 gate = rt->rt_gateway; 1254 SDL(gate)->sdl_type = ifp->if_type; 1255 SDL(gate)->sdl_index = ifp->if_index; 1256 if (ln) 1257 nd6_llinfo_settimer(ln, 0); 1258 if ((rt->rt_flags & RTF_CLONING) != 0) 1259 break; 1260 } 1261 /* 1262 * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here. 1263 * We don't do that here since llinfo is not ready yet. 1264 * 1265 * There are also couple of other things to be discussed: 1266 * - unsolicited NA code needs improvement beforehand 1267 * - RFC2461 says we MAY send multicast unsolicited NA 1268 * (7.2.6 paragraph 4), however, it also says that we 1269 * SHOULD provide a mechanism to prevent multicast NA storm. 1270 * we don't have anything like it right now. 1271 * note that the mechanism needs a mutual agreement 1272 * between proxies, which means that we need to implement 1273 * a new protocol, or a new kludge. 1274 * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA. 1275 * we need to check ip6forwarding before sending it. 1276 * (or should we allow proxy ND configuration only for 1277 * routers? there's no mention about proxy ND from hosts) 1278 */ 1279 /* FALLTHROUGH */ 1280 case RTM_RESOLVE: 1281 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) { 1282 /* 1283 * Address resolution isn't necessary for a point to 1284 * point link, so we can skip this test for a p2p link. 1285 */ 1286 if (gate->sa_family != AF_LINK || 1287 gate->sa_len < sizeof(null_sdl)) { 1288 log(LOG_DEBUG, 1289 "nd6_rtrequest: bad gateway value: %s\n", 1290 if_name(ifp)); 1291 break; 1292 } 1293 SDL(gate)->sdl_type = ifp->if_type; 1294 SDL(gate)->sdl_index = ifp->if_index; 1295 } 1296 if (ln != NULL) 1297 break; /* This happens on a route change */ 1298 /* 1299 * Case 2: This route may come from cloning, or a manual route 1300 * add with a LL address. 1301 */ 1302 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln)); 1303 rt->rt_llinfo = (caddr_t)ln; 1304 if (ln == NULL) { 1305 log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n"); 1306 break; 1307 } 1308 V_nd6_inuse++; 1309 V_nd6_allocated++; 1310 bzero(ln, sizeof(*ln)); 1311 RT_ADDREF(rt); 1312 ln->ln_rt = rt; 1313 callout_init(&ln->ln_timer_ch, 0); 1314 1315 /* this is required for "ndp" command. - shin */ 1316 if (req == RTM_ADD) { 1317 /* 1318 * gate should have some valid AF_LINK entry, 1319 * and ln->ln_expire should have some lifetime 1320 * which is specified by ndp command. 1321 */ 1322 ln->ln_state = ND6_LLINFO_REACHABLE; 1323 ln->ln_byhint = 0; 1324 } else { 1325 /* 1326 * When req == RTM_RESOLVE, rt is created and 1327 * initialized in rtrequest(), so rt_expire is 0. 1328 */ 1329 ln->ln_state = ND6_LLINFO_NOSTATE; 1330 nd6_llinfo_settimer(ln, 0); 1331 } 1332 rt->rt_flags |= RTF_LLINFO; 1333 ln->ln_next = V_llinfo_nd6.ln_next; 1334 V_llinfo_nd6.ln_next = ln; 1335 ln->ln_prev = &V_llinfo_nd6; 1336 ln->ln_next->ln_prev = ln; 1337 1338 /* 1339 * check if rt_key(rt) is one of my address assigned 1340 * to the interface. 1341 */ 1342 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp, 1343 &SIN6(rt_key(rt))->sin6_addr); 1344 if (ifa) { 1345 caddr_t macp = nd6_ifptomac(ifp); 1346 nd6_llinfo_settimer(ln, -1); 1347 ln->ln_state = ND6_LLINFO_REACHABLE; 1348 ln->ln_byhint = 0; 1349 if (macp) { 1350 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen); 1351 SDL(gate)->sdl_alen = ifp->if_addrlen; 1352 } 1353 if (V_nd6_useloopback) { 1354 rt->rt_ifp = &V_loif[0]; /* XXX */ 1355 /* 1356 * Make sure rt_ifa be equal to the ifaddr 1357 * corresponding to the address. 1358 * We need this because when we refer 1359 * rt_ifa->ia6_flags in ip6_input, we assume 1360 * that the rt_ifa points to the address instead 1361 * of the loopback address. 1362 */ 1363 if (ifa != rt->rt_ifa) { 1364 IFAFREE(rt->rt_ifa); 1365 IFAREF(ifa); 1366 rt->rt_ifa = ifa; 1367 } 1368 } 1369 } else if (rt->rt_flags & RTF_ANNOUNCE) { 1370 nd6_llinfo_settimer(ln, -1); 1371 ln->ln_state = ND6_LLINFO_REACHABLE; 1372 ln->ln_byhint = 0; 1373 1374 /* join solicited node multicast for proxy ND */ 1375 if (ifp->if_flags & IFF_MULTICAST) { 1376 struct in6_addr llsol; 1377 int error; 1378 1379 llsol = SIN6(rt_key(rt))->sin6_addr; 1380 llsol.s6_addr32[0] = IPV6_ADDR_INT32_MLL; 1381 llsol.s6_addr32[1] = 0; 1382 llsol.s6_addr32[2] = htonl(1); 1383 llsol.s6_addr8[12] = 0xff; 1384 if (in6_setscope(&llsol, ifp, NULL)) 1385 break; 1386 if (in6_addmulti(&llsol, ifp, 1387 &error, 0) == NULL) { 1388 char ip6buf[INET6_ADDRSTRLEN]; 1389 nd6log((LOG_ERR, "%s: failed to join " 1390 "%s (errno=%d)\n", if_name(ifp), 1391 ip6_sprintf(ip6buf, &llsol), 1392 error)); 1393 } 1394 } 1395 } 1396 break; 1397 1398 case RTM_DELETE: 1399 if (ln == NULL) 1400 break; 1401 /* leave from solicited node multicast for proxy ND */ 1402 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 && 1403 (ifp->if_flags & IFF_MULTICAST) != 0) { 1404 struct in6_addr llsol; 1405 struct in6_multi *in6m; 1406 1407 llsol = SIN6(rt_key(rt))->sin6_addr; 1408 llsol.s6_addr32[0] = IPV6_ADDR_INT32_MLL; 1409 llsol.s6_addr32[1] = 0; 1410 llsol.s6_addr32[2] = htonl(1); 1411 llsol.s6_addr8[12] = 0xff; 1412 if (in6_setscope(&llsol, ifp, NULL) == 0) { 1413 IN6_LOOKUP_MULTI(llsol, ifp, in6m); 1414 if (in6m) 1415 in6_delmulti(in6m); 1416 } else 1417 ; /* XXX: should not happen. bark here? */ 1418 } 1419 V_nd6_inuse--; 1420 ln->ln_next->ln_prev = ln->ln_prev; 1421 ln->ln_prev->ln_next = ln->ln_next; 1422 ln->ln_prev = NULL; 1423 nd6_llinfo_settimer(ln, -1); 1424 RT_REMREF(rt); 1425 rt->rt_llinfo = 0; 1426 rt->rt_flags &= ~RTF_LLINFO; 1427 clear_llinfo_pqueue(ln); 1428 Free((caddr_t)ln); 1429 } 1430 } 1431 1432 int 1433 nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) 1434 { 1435 INIT_VNET_INET6(ifp->if_vnet); 1436 struct in6_drlist *drl = (struct in6_drlist *)data; 1437 struct in6_oprlist *oprl = (struct in6_oprlist *)data; 1438 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1439 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1440 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1441 struct nd_defrouter *dr; 1442 struct nd_prefix *pr; 1443 struct rtentry *rt; 1444 int i = 0, error = 0; 1445 int s; 1446 1447 switch (cmd) { 1448 case SIOCGDRLST_IN6: 1449 /* 1450 * obsolete API, use sysctl under net.inet6.icmp6 1451 */ 1452 bzero(drl, sizeof(*drl)); 1453 s = splnet(); 1454 dr = TAILQ_FIRST(&V_nd_defrouter); 1455 while (dr && i < DRLSTSIZ) { 1456 drl->defrouter[i].rtaddr = dr->rtaddr; 1457 in6_clearscope(&drl->defrouter[i].rtaddr); 1458 1459 drl->defrouter[i].flags = dr->flags; 1460 drl->defrouter[i].rtlifetime = dr->rtlifetime; 1461 drl->defrouter[i].expire = dr->expire; 1462 drl->defrouter[i].if_index = dr->ifp->if_index; 1463 i++; 1464 dr = TAILQ_NEXT(dr, dr_entry); 1465 } 1466 splx(s); 1467 break; 1468 case SIOCGPRLST_IN6: 1469 /* 1470 * obsolete API, use sysctl under net.inet6.icmp6 1471 * 1472 * XXX the structure in6_prlist was changed in backward- 1473 * incompatible manner. in6_oprlist is used for SIOCGPRLST_IN6, 1474 * in6_prlist is used for nd6_sysctl() - fill_prlist(). 1475 */ 1476 /* 1477 * XXX meaning of fields, especialy "raflags", is very 1478 * differnet between RA prefix list and RR/static prefix list. 1479 * how about separating ioctls into two? 1480 */ 1481 bzero(oprl, sizeof(*oprl)); 1482 s = splnet(); 1483 pr = V_nd_prefix.lh_first; 1484 while (pr && i < PRLSTSIZ) { 1485 struct nd_pfxrouter *pfr; 1486 int j; 1487 1488 oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr; 1489 oprl->prefix[i].raflags = pr->ndpr_raf; 1490 oprl->prefix[i].prefixlen = pr->ndpr_plen; 1491 oprl->prefix[i].vltime = pr->ndpr_vltime; 1492 oprl->prefix[i].pltime = pr->ndpr_pltime; 1493 oprl->prefix[i].if_index = pr->ndpr_ifp->if_index; 1494 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 1495 oprl->prefix[i].expire = 0; 1496 else { 1497 time_t maxexpire; 1498 1499 /* XXX: we assume time_t is signed. */ 1500 maxexpire = (-1) & 1501 ~((time_t)1 << 1502 ((sizeof(maxexpire) * 8) - 1)); 1503 if (pr->ndpr_vltime < 1504 maxexpire - pr->ndpr_lastupdate) { 1505 oprl->prefix[i].expire = 1506 pr->ndpr_lastupdate + 1507 pr->ndpr_vltime; 1508 } else 1509 oprl->prefix[i].expire = maxexpire; 1510 } 1511 1512 pfr = pr->ndpr_advrtrs.lh_first; 1513 j = 0; 1514 while (pfr) { 1515 if (j < DRLSTSIZ) { 1516 #define RTRADDR oprl->prefix[i].advrtr[j] 1517 RTRADDR = pfr->router->rtaddr; 1518 in6_clearscope(&RTRADDR); 1519 #undef RTRADDR 1520 } 1521 j++; 1522 pfr = pfr->pfr_next; 1523 } 1524 oprl->prefix[i].advrtrs = j; 1525 oprl->prefix[i].origin = PR_ORIG_RA; 1526 1527 i++; 1528 pr = pr->ndpr_next; 1529 } 1530 splx(s); 1531 1532 break; 1533 case OSIOCGIFINFO_IN6: 1534 #define ND ndi->ndi 1535 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1536 bzero(&ND, sizeof(ND)); 1537 ND.linkmtu = IN6_LINKMTU(ifp); 1538 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1539 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1540 ND.reachable = ND_IFINFO(ifp)->reachable; 1541 ND.retrans = ND_IFINFO(ifp)->retrans; 1542 ND.flags = ND_IFINFO(ifp)->flags; 1543 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1544 ND.chlim = ND_IFINFO(ifp)->chlim; 1545 break; 1546 case SIOCGIFINFO_IN6: 1547 ND = *ND_IFINFO(ifp); 1548 break; 1549 case SIOCSIFINFO_IN6: 1550 /* 1551 * used to change host variables from userland. 1552 * intented for a use on router to reflect RA configurations. 1553 */ 1554 /* 0 means 'unspecified' */ 1555 if (ND.linkmtu != 0) { 1556 if (ND.linkmtu < IPV6_MMTU || 1557 ND.linkmtu > IN6_LINKMTU(ifp)) { 1558 error = EINVAL; 1559 break; 1560 } 1561 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1562 } 1563 1564 if (ND.basereachable != 0) { 1565 int obasereachable = ND_IFINFO(ifp)->basereachable; 1566 1567 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1568 if (ND.basereachable != obasereachable) 1569 ND_IFINFO(ifp)->reachable = 1570 ND_COMPUTE_RTIME(ND.basereachable); 1571 } 1572 if (ND.retrans != 0) 1573 ND_IFINFO(ifp)->retrans = ND.retrans; 1574 if (ND.chlim != 0) 1575 ND_IFINFO(ifp)->chlim = ND.chlim; 1576 /* FALLTHROUGH */ 1577 case SIOCSIFINFO_FLAGS: 1578 ND_IFINFO(ifp)->flags = ND.flags; 1579 break; 1580 #undef ND 1581 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1582 /* sync kernel routing table with the default router list */ 1583 defrouter_reset(); 1584 defrouter_select(); 1585 break; 1586 case SIOCSPFXFLUSH_IN6: 1587 { 1588 /* flush all the prefix advertised by routers */ 1589 struct nd_prefix *pr, *next; 1590 1591 s = splnet(); 1592 for (pr = V_nd_prefix.lh_first; pr; pr = next) { 1593 struct in6_ifaddr *ia, *ia_next; 1594 1595 next = pr->ndpr_next; 1596 1597 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1598 continue; /* XXX */ 1599 1600 /* do we really have to remove addresses as well? */ 1601 for (ia = V_in6_ifaddr; ia; ia = ia_next) { 1602 /* ia might be removed. keep the next ptr. */ 1603 ia_next = ia->ia_next; 1604 1605 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1606 continue; 1607 1608 if (ia->ia6_ndpr == pr) 1609 in6_purgeaddr(&ia->ia_ifa); 1610 } 1611 prelist_remove(pr); 1612 } 1613 splx(s); 1614 break; 1615 } 1616 case SIOCSRTRFLUSH_IN6: 1617 { 1618 /* flush all the default routers */ 1619 struct nd_defrouter *dr, *next; 1620 1621 s = splnet(); 1622 defrouter_reset(); 1623 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; dr = next) { 1624 next = TAILQ_NEXT(dr, dr_entry); 1625 defrtrlist_del(dr); 1626 } 1627 defrouter_select(); 1628 splx(s); 1629 break; 1630 } 1631 case SIOCGNBRINFO_IN6: 1632 { 1633 struct llinfo_nd6 *ln; 1634 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1635 1636 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1637 return (error); 1638 1639 s = splnet(); 1640 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL) { 1641 error = EINVAL; 1642 splx(s); 1643 break; 1644 } 1645 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1646 nbi->state = ln->ln_state; 1647 nbi->asked = ln->ln_asked; 1648 nbi->isrouter = ln->ln_router; 1649 nbi->expire = ln->ln_expire; 1650 splx(s); 1651 1652 break; 1653 } 1654 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1655 ndif->ifindex = V_nd6_defifindex; 1656 break; 1657 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1658 return (nd6_setdefaultiface(ndif->ifindex)); 1659 } 1660 return (error); 1661 } 1662 1663 /* 1664 * Create neighbor cache entry and cache link-layer address, 1665 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1666 * 1667 * type - ICMP6 type 1668 * code - type dependent information 1669 */ 1670 struct rtentry * 1671 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr, 1672 int lladdrlen, int type, int code) 1673 { 1674 INIT_VNET_INET6(curvnet); 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 rt = nd6_lookup(from, 1, ifp); 1706 is_newentry = 1; 1707 } else { 1708 /* do nothing if static ndp is set */ 1709 if (rt->rt_flags & RTF_STATIC) 1710 return NULL; 1711 is_newentry = 0; 1712 } 1713 1714 if (rt == NULL) 1715 return NULL; 1716 if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) { 1717 fail: 1718 (void)nd6_free(rt, 0); 1719 return NULL; 1720 } 1721 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 1722 if (ln == NULL) 1723 goto fail; 1724 if (rt->rt_gateway == NULL) 1725 goto fail; 1726 if (rt->rt_gateway->sa_family != AF_LINK) 1727 goto fail; 1728 sdl = SDL(rt->rt_gateway); 1729 1730 olladdr = (sdl->sdl_alen) ? 1 : 0; 1731 if (olladdr && lladdr) { 1732 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 1733 llchange = 1; 1734 else 1735 llchange = 0; 1736 } else 1737 llchange = 0; 1738 1739 /* 1740 * newentry olladdr lladdr llchange (*=record) 1741 * 0 n n -- (1) 1742 * 0 y n -- (2) 1743 * 0 n y -- (3) * STALE 1744 * 0 y y n (4) * 1745 * 0 y y y (5) * STALE 1746 * 1 -- n -- (6) NOSTATE(= PASSIVE) 1747 * 1 -- y -- (7) * STALE 1748 */ 1749 1750 if (lladdr) { /* (3-5) and (7) */ 1751 /* 1752 * Record source link-layer address 1753 * XXX is it dependent to ifp->if_type? 1754 */ 1755 sdl->sdl_alen = ifp->if_addrlen; 1756 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 1757 } 1758 1759 if (!is_newentry) { 1760 if ((!olladdr && lladdr != NULL) || /* (3) */ 1761 (olladdr && lladdr != NULL && llchange)) { /* (5) */ 1762 do_update = 1; 1763 newstate = ND6_LLINFO_STALE; 1764 } else /* (1-2,4) */ 1765 do_update = 0; 1766 } else { 1767 do_update = 1; 1768 if (lladdr == NULL) /* (6) */ 1769 newstate = ND6_LLINFO_NOSTATE; 1770 else /* (7) */ 1771 newstate = ND6_LLINFO_STALE; 1772 } 1773 1774 if (do_update) { 1775 /* 1776 * Update the state of the neighbor cache. 1777 */ 1778 ln->ln_state = newstate; 1779 1780 if (ln->ln_state == ND6_LLINFO_STALE) { 1781 /* 1782 * XXX: since nd6_output() below will cause 1783 * state tansition to DELAY and reset the timer, 1784 * we must set the timer now, although it is actually 1785 * meaningless. 1786 */ 1787 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 1788 1789 if (ln->ln_hold) { 1790 struct mbuf *m_hold, *m_hold_next; 1791 1792 /* 1793 * reset the ln_hold in advance, to explicitly 1794 * prevent a ln_hold lookup in nd6_output() 1795 * (wouldn't happen, though...) 1796 */ 1797 for (m_hold = ln->ln_hold, ln->ln_hold = NULL; 1798 m_hold; m_hold = m_hold_next) { 1799 m_hold_next = m_hold->m_nextpkt; 1800 m_hold->m_nextpkt = NULL; 1801 1802 /* 1803 * we assume ifp is not a p2p here, so 1804 * just set the 2nd argument as the 1805 * 1st one. 1806 */ 1807 nd6_output(ifp, ifp, m_hold, 1808 (struct sockaddr_in6 *)rt_key(rt), 1809 rt); 1810 } 1811 } 1812 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 1813 /* probe right away */ 1814 nd6_llinfo_settimer((void *)ln, 0); 1815 } 1816 } 1817 1818 /* 1819 * ICMP6 type dependent behavior. 1820 * 1821 * NS: clear IsRouter if new entry 1822 * RS: clear IsRouter 1823 * RA: set IsRouter if there's lladdr 1824 * redir: clear IsRouter if new entry 1825 * 1826 * RA case, (1): 1827 * The spec says that we must set IsRouter in the following cases: 1828 * - If lladdr exist, set IsRouter. This means (1-5). 1829 * - If it is old entry (!newentry), set IsRouter. This means (7). 1830 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1831 * A quetion arises for (1) case. (1) case has no lladdr in the 1832 * neighbor cache, this is similar to (6). 1833 * This case is rare but we figured that we MUST NOT set IsRouter. 1834 * 1835 * newentry olladdr lladdr llchange NS RS RA redir 1836 * D R 1837 * 0 n n -- (1) c ? s 1838 * 0 y n -- (2) c s s 1839 * 0 n y -- (3) c s s 1840 * 0 y y n (4) c s s 1841 * 0 y y y (5) c s s 1842 * 1 -- n -- (6) c c c s 1843 * 1 -- y -- (7) c c s c s 1844 * 1845 * (c=clear s=set) 1846 */ 1847 switch (type & 0xff) { 1848 case ND_NEIGHBOR_SOLICIT: 1849 /* 1850 * New entry must have is_router flag cleared. 1851 */ 1852 if (is_newentry) /* (6-7) */ 1853 ln->ln_router = 0; 1854 break; 1855 case ND_REDIRECT: 1856 /* 1857 * If the icmp is a redirect to a better router, always set the 1858 * is_router flag. Otherwise, if the entry is newly created, 1859 * clear the flag. [RFC 2461, sec 8.3] 1860 */ 1861 if (code == ND_REDIRECT_ROUTER) 1862 ln->ln_router = 1; 1863 else if (is_newentry) /* (6-7) */ 1864 ln->ln_router = 0; 1865 break; 1866 case ND_ROUTER_SOLICIT: 1867 /* 1868 * is_router flag must always be cleared. 1869 */ 1870 ln->ln_router = 0; 1871 break; 1872 case ND_ROUTER_ADVERT: 1873 /* 1874 * Mark an entry with lladdr as a router. 1875 */ 1876 if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */ 1877 (is_newentry && lladdr)) { /* (7) */ 1878 ln->ln_router = 1; 1879 } 1880 break; 1881 } 1882 1883 /* 1884 * When the link-layer address of a router changes, select the 1885 * best router again. In particular, when the neighbor entry is newly 1886 * created, it might affect the selection policy. 1887 * Question: can we restrict the first condition to the "is_newentry" 1888 * case? 1889 * XXX: when we hear an RA from a new router with the link-layer 1890 * address option, defrouter_select() is called twice, since 1891 * defrtrlist_update called the function as well. However, I believe 1892 * we can compromise the overhead, since it only happens the first 1893 * time. 1894 * XXX: although defrouter_select() should not have a bad effect 1895 * for those are not autoconfigured hosts, we explicitly avoid such 1896 * cases for safety. 1897 */ 1898 if (do_update && ln->ln_router && !V_ip6_forwarding && V_ip6_accept_rtadv) 1899 defrouter_select(); 1900 1901 return rt; 1902 } 1903 1904 static void 1905 nd6_slowtimo(void *arg) 1906 { 1907 CURVNET_SET((struct vnet *) arg); 1908 INIT_VNET_NET((struct vnet *) arg); 1909 INIT_VNET_INET6((struct vnet *) arg); 1910 struct nd_ifinfo *nd6if; 1911 struct ifnet *ifp; 1912 1913 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 1914 nd6_slowtimo, NULL); 1915 IFNET_RLOCK(); 1916 for (ifp = TAILQ_FIRST(&V_ifnet); ifp; 1917 ifp = TAILQ_NEXT(ifp, if_list)) { 1918 nd6if = ND_IFINFO(ifp); 1919 if (nd6if->basereachable && /* already initialized */ 1920 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 1921 /* 1922 * Since reachable time rarely changes by router 1923 * advertisements, we SHOULD insure that a new random 1924 * value gets recomputed at least once every few hours. 1925 * (RFC 2461, 6.3.4) 1926 */ 1927 nd6if->recalctm = V_nd6_recalc_reachtm_interval; 1928 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 1929 } 1930 } 1931 IFNET_RUNLOCK(); 1932 CURVNET_RESTORE(); 1933 } 1934 1935 #define senderr(e) { error = (e); goto bad;} 1936 int 1937 nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m0, 1938 struct sockaddr_in6 *dst, struct rtentry *rt0) 1939 { 1940 INIT_VNET_INET6(curvnet); 1941 struct mbuf *m = m0; 1942 struct rtentry *rt = rt0; 1943 struct sockaddr_in6 *gw6 = NULL; 1944 struct llinfo_nd6 *ln = NULL; 1945 int error = 0; 1946 1947 if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr)) 1948 goto sendpkt; 1949 1950 if (nd6_need_cache(ifp) == 0) 1951 goto sendpkt; 1952 1953 /* 1954 * next hop determination. This routine is derived from ether_output. 1955 */ 1956 /* NB: the locking here is tortuous... */ 1957 if (rt != NULL) 1958 RT_LOCK(rt); 1959 again: 1960 if (rt != NULL) { 1961 if ((rt->rt_flags & RTF_UP) == 0) { 1962 RT_UNLOCK(rt); 1963 rt0 = rt = rtalloc1((struct sockaddr *)dst, 1, 0UL); 1964 if (rt != NULL) { 1965 RT_REMREF(rt); 1966 if (rt->rt_ifp != ifp) 1967 /* 1968 * XXX maybe we should update ifp too, 1969 * but the original code didn't and I 1970 * don't know what is correct here. 1971 */ 1972 goto again; 1973 } else 1974 senderr(EHOSTUNREACH); 1975 } 1976 1977 if (rt->rt_flags & RTF_GATEWAY) { 1978 gw6 = (struct sockaddr_in6 *)rt->rt_gateway; 1979 1980 /* 1981 * We skip link-layer address resolution and NUD 1982 * if the gateway is not a neighbor from ND point 1983 * of view, regardless of the value of nd_ifinfo.flags. 1984 * The second condition is a bit tricky; we skip 1985 * if the gateway is our own address, which is 1986 * sometimes used to install a route to a p2p link. 1987 */ 1988 if (!nd6_is_addr_neighbor(gw6, ifp) || 1989 in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) { 1990 RT_UNLOCK(rt); 1991 /* 1992 * We allow this kind of tricky route only 1993 * when the outgoing interface is p2p. 1994 * XXX: we may need a more generic rule here. 1995 */ 1996 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 1997 senderr(EHOSTUNREACH); 1998 1999 goto sendpkt; 2000 } 2001 2002 if (rt->rt_gwroute == NULL) 2003 goto lookup; 2004 rt = rt->rt_gwroute; 2005 RT_LOCK(rt); /* NB: gwroute */ 2006 if ((rt->rt_flags & RTF_UP) == 0) { 2007 RTFREE_LOCKED(rt); /* unlock gwroute */ 2008 rt = rt0; 2009 rt0->rt_gwroute = NULL; 2010 lookup: 2011 RT_UNLOCK(rt0); 2012 rt = rtalloc1(rt->rt_gateway, 1, 0UL); 2013 if (rt == rt0) { 2014 RT_REMREF(rt0); 2015 RT_UNLOCK(rt0); 2016 senderr(EHOSTUNREACH); 2017 } 2018 RT_LOCK(rt0); 2019 if (rt0->rt_gwroute != NULL) 2020 RTFREE(rt0->rt_gwroute); 2021 rt0->rt_gwroute = rt; 2022 if (rt == NULL) { 2023 RT_UNLOCK(rt0); 2024 senderr(EHOSTUNREACH); 2025 } 2026 } 2027 RT_UNLOCK(rt0); 2028 } 2029 RT_UNLOCK(rt); 2030 } 2031 2032 /* 2033 * Address resolution or Neighbor Unreachability Detection 2034 * for the next hop. 2035 * At this point, the destination of the packet must be a unicast 2036 * or an anycast address(i.e. not a multicast). 2037 */ 2038 2039 /* Look up the neighbor cache for the nexthop */ 2040 if (rt && (rt->rt_flags & RTF_LLINFO) != 0) 2041 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2042 else { 2043 /* 2044 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 2045 * the condition below is not very efficient. But we believe 2046 * it is tolerable, because this should be a rare case. 2047 */ 2048 if (nd6_is_addr_neighbor(dst, ifp) && 2049 (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL) 2050 ln = (struct llinfo_nd6 *)rt->rt_llinfo; 2051 } 2052 if (ln == NULL || rt == NULL) { 2053 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 && 2054 !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { 2055 char ip6buf[INET6_ADDRSTRLEN]; 2056 log(LOG_DEBUG, 2057 "nd6_output: can't allocate llinfo for %s " 2058 "(ln=%p, rt=%p)\n", 2059 ip6_sprintf(ip6buf, &dst->sin6_addr), ln, rt); 2060 senderr(EIO); /* XXX: good error? */ 2061 } 2062 2063 goto sendpkt; /* send anyway */ 2064 } 2065 2066 /* We don't have to do link-layer address resolution on a p2p link. */ 2067 if ((ifp->if_flags & IFF_POINTOPOINT) != 0 && 2068 ln->ln_state < ND6_LLINFO_REACHABLE) { 2069 ln->ln_state = ND6_LLINFO_STALE; 2070 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 2071 } 2072 2073 /* 2074 * The first time we send a packet to a neighbor whose entry is 2075 * STALE, we have to change the state to DELAY and a sets a timer to 2076 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2077 * neighbor unreachability detection on expiration. 2078 * (RFC 2461 7.3.3) 2079 */ 2080 if (ln->ln_state == ND6_LLINFO_STALE) { 2081 ln->ln_asked = 0; 2082 ln->ln_state = ND6_LLINFO_DELAY; 2083 nd6_llinfo_settimer(ln, (long)V_nd6_delay * hz); 2084 } 2085 2086 /* 2087 * If the neighbor cache entry has a state other than INCOMPLETE 2088 * (i.e. its link-layer address is already resolved), just 2089 * send the packet. 2090 */ 2091 if (ln->ln_state > ND6_LLINFO_INCOMPLETE) 2092 goto sendpkt; 2093 2094 /* 2095 * There is a neighbor cache entry, but no ethernet address 2096 * response yet. Append this latest packet to the end of the 2097 * packet queue in the mbuf, unless the number of the packet 2098 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, 2099 * the oldest packet in the queue will be removed. 2100 */ 2101 if (ln->ln_state == ND6_LLINFO_NOSTATE) 2102 ln->ln_state = ND6_LLINFO_INCOMPLETE; 2103 if (ln->ln_hold) { 2104 struct mbuf *m_hold; 2105 int i; 2106 2107 i = 0; 2108 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold->m_nextpkt) { 2109 i++; 2110 if (m_hold->m_nextpkt == NULL) { 2111 m_hold->m_nextpkt = m; 2112 break; 2113 } 2114 } 2115 while (i >= V_nd6_maxqueuelen) { 2116 m_hold = ln->ln_hold; 2117 ln->ln_hold = ln->ln_hold->m_nextpkt; 2118 m_freem(m_hold); 2119 i--; 2120 } 2121 } else { 2122 ln->ln_hold = m; 2123 } 2124 2125 /* 2126 * If there has been no NS for the neighbor after entering the 2127 * INCOMPLETE state, send the first solicitation. 2128 */ 2129 if (!ND6_LLINFO_PERMANENT(ln) && ln->ln_asked == 0) { 2130 ln->ln_asked++; 2131 nd6_llinfo_settimer(ln, 2132 (long)ND_IFINFO(ifp)->retrans * hz / 1000); 2133 nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); 2134 } 2135 return (0); 2136 2137 sendpkt: 2138 /* discard the packet if IPv6 operation is disabled on the interface */ 2139 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 2140 error = ENETDOWN; /* better error? */ 2141 goto bad; 2142 } 2143 2144 #ifdef MAC 2145 mac_netinet6_nd6_send(ifp, m); 2146 #endif 2147 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 2148 return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst, 2149 rt)); 2150 } 2151 return ((*ifp->if_output)(ifp, m, (struct sockaddr *)dst, rt)); 2152 2153 bad: 2154 if (m) 2155 m_freem(m); 2156 return (error); 2157 } 2158 #undef senderr 2159 2160 int 2161 nd6_need_cache(struct ifnet *ifp) 2162 { 2163 /* 2164 * XXX: we currently do not make neighbor cache on any interface 2165 * other than ARCnet, Ethernet, FDDI and GIF. 2166 * 2167 * RFC2893 says: 2168 * - unidirectional tunnels needs no ND 2169 */ 2170 switch (ifp->if_type) { 2171 case IFT_ARCNET: 2172 case IFT_ETHER: 2173 case IFT_FDDI: 2174 case IFT_IEEE1394: 2175 #ifdef IFT_L2VLAN 2176 case IFT_L2VLAN: 2177 #endif 2178 #ifdef IFT_IEEE80211 2179 case IFT_IEEE80211: 2180 #endif 2181 #ifdef IFT_CARP 2182 case IFT_CARP: 2183 #endif 2184 case IFT_GIF: /* XXX need more cases? */ 2185 case IFT_PPP: 2186 case IFT_TUNNEL: 2187 case IFT_BRIDGE: 2188 case IFT_PROPVIRTUAL: 2189 return (1); 2190 default: 2191 return (0); 2192 } 2193 } 2194 2195 int 2196 nd6_storelladdr(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m, 2197 struct sockaddr *dst, u_char *desten) 2198 { 2199 struct sockaddr_dl *sdl; 2200 struct rtentry *rt; 2201 int error; 2202 2203 if (m->m_flags & M_MCAST) { 2204 int i; 2205 2206 switch (ifp->if_type) { 2207 case IFT_ETHER: 2208 case IFT_FDDI: 2209 #ifdef IFT_L2VLAN 2210 case IFT_L2VLAN: 2211 #endif 2212 #ifdef IFT_IEEE80211 2213 case IFT_IEEE80211: 2214 #endif 2215 case IFT_BRIDGE: 2216 case IFT_ISO88025: 2217 ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr, 2218 desten); 2219 return (0); 2220 case IFT_IEEE1394: 2221 /* 2222 * netbsd can use if_broadcastaddr, but we don't do so 2223 * to reduce # of ifdef. 2224 */ 2225 for (i = 0; i < ifp->if_addrlen; i++) 2226 desten[i] = ~0; 2227 return (0); 2228 case IFT_ARCNET: 2229 *desten = 0; 2230 return (0); 2231 default: 2232 m_freem(m); 2233 return (EAFNOSUPPORT); 2234 } 2235 } 2236 2237 if (rt0 == NULL) { 2238 /* this could happen, if we could not allocate memory */ 2239 m_freem(m); 2240 return (ENOMEM); 2241 } 2242 2243 error = rt_check(&rt, &rt0, dst); 2244 if (error) { 2245 m_freem(m); 2246 return (error); 2247 } 2248 RT_UNLOCK(rt); 2249 2250 if (rt->rt_gateway->sa_family != AF_LINK) { 2251 printf("nd6_storelladdr: something odd happens\n"); 2252 m_freem(m); 2253 return (EINVAL); 2254 } 2255 sdl = SDL(rt->rt_gateway); 2256 if (sdl->sdl_alen == 0) { 2257 /* this should be impossible, but we bark here for debugging */ 2258 printf("nd6_storelladdr: sdl_alen == 0\n"); 2259 m_freem(m); 2260 return (EINVAL); 2261 } 2262 2263 bcopy(LLADDR(sdl), desten, sdl->sdl_alen); 2264 return (0); 2265 } 2266 2267 static void 2268 clear_llinfo_pqueue(struct llinfo_nd6 *ln) 2269 { 2270 struct mbuf *m_hold, *m_hold_next; 2271 2272 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold_next) { 2273 m_hold_next = m_hold->m_nextpkt; 2274 m_hold->m_nextpkt = NULL; 2275 m_freem(m_hold); 2276 } 2277 2278 ln->ln_hold = NULL; 2279 return; 2280 } 2281 2282 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS); 2283 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS); 2284 #ifdef SYSCTL_DECL 2285 SYSCTL_DECL(_net_inet6_icmp6); 2286 #endif 2287 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist, 2288 CTLFLAG_RD, nd6_sysctl_drlist, ""); 2289 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist, 2290 CTLFLAG_RD, nd6_sysctl_prlist, ""); 2291 SYSCTL_V_INT(V_NET, vnet_inet6, _net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, 2292 nd6_maxqueuelen, CTLFLAG_RW, nd6_maxqueuelen, 1, ""); 2293 2294 static int 2295 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS) 2296 { 2297 INIT_VNET_INET6(curvnet); 2298 int error; 2299 char buf[1024] __aligned(4); 2300 struct in6_defrouter *d, *de; 2301 struct nd_defrouter *dr; 2302 2303 if (req->newptr) 2304 return EPERM; 2305 error = 0; 2306 2307 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 2308 dr = TAILQ_NEXT(dr, dr_entry)) { 2309 d = (struct in6_defrouter *)buf; 2310 de = (struct in6_defrouter *)(buf + sizeof(buf)); 2311 2312 if (d + 1 <= de) { 2313 bzero(d, sizeof(*d)); 2314 d->rtaddr.sin6_family = AF_INET6; 2315 d->rtaddr.sin6_len = sizeof(d->rtaddr); 2316 d->rtaddr.sin6_addr = dr->rtaddr; 2317 error = sa6_recoverscope(&d->rtaddr); 2318 if (error != 0) 2319 return (error); 2320 d->flags = dr->flags; 2321 d->rtlifetime = dr->rtlifetime; 2322 d->expire = dr->expire; 2323 d->if_index = dr->ifp->if_index; 2324 } else 2325 panic("buffer too short"); 2326 2327 error = SYSCTL_OUT(req, buf, sizeof(*d)); 2328 if (error) 2329 break; 2330 } 2331 2332 return (error); 2333 } 2334 2335 static int 2336 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS) 2337 { 2338 INIT_VNET_INET6(curvnet); 2339 int error; 2340 char buf[1024] __aligned(4); 2341 struct in6_prefix *p, *pe; 2342 struct nd_prefix *pr; 2343 char ip6buf[INET6_ADDRSTRLEN]; 2344 2345 if (req->newptr) 2346 return EPERM; 2347 error = 0; 2348 2349 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 2350 u_short advrtrs; 2351 size_t advance; 2352 struct sockaddr_in6 *sin6, *s6; 2353 struct nd_pfxrouter *pfr; 2354 2355 p = (struct in6_prefix *)buf; 2356 pe = (struct in6_prefix *)(buf + sizeof(buf)); 2357 2358 if (p + 1 <= pe) { 2359 bzero(p, sizeof(*p)); 2360 sin6 = (struct sockaddr_in6 *)(p + 1); 2361 2362 p->prefix = pr->ndpr_prefix; 2363 if (sa6_recoverscope(&p->prefix)) { 2364 log(LOG_ERR, 2365 "scope error in prefix list (%s)\n", 2366 ip6_sprintf(ip6buf, &p->prefix.sin6_addr)); 2367 /* XXX: press on... */ 2368 } 2369 p->raflags = pr->ndpr_raf; 2370 p->prefixlen = pr->ndpr_plen; 2371 p->vltime = pr->ndpr_vltime; 2372 p->pltime = pr->ndpr_pltime; 2373 p->if_index = pr->ndpr_ifp->if_index; 2374 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2375 p->expire = 0; 2376 else { 2377 time_t maxexpire; 2378 2379 /* XXX: we assume time_t is signed. */ 2380 maxexpire = (-1) & 2381 ~((time_t)1 << 2382 ((sizeof(maxexpire) * 8) - 1)); 2383 if (pr->ndpr_vltime < 2384 maxexpire - pr->ndpr_lastupdate) { 2385 p->expire = pr->ndpr_lastupdate + 2386 pr->ndpr_vltime; 2387 } else 2388 p->expire = maxexpire; 2389 } 2390 p->refcnt = pr->ndpr_refcnt; 2391 p->flags = pr->ndpr_stateflags; 2392 p->origin = PR_ORIG_RA; 2393 advrtrs = 0; 2394 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; 2395 pfr = pfr->pfr_next) { 2396 if ((void *)&sin6[advrtrs + 1] > (void *)pe) { 2397 advrtrs++; 2398 continue; 2399 } 2400 s6 = &sin6[advrtrs]; 2401 bzero(s6, sizeof(*s6)); 2402 s6->sin6_family = AF_INET6; 2403 s6->sin6_len = sizeof(*sin6); 2404 s6->sin6_addr = pfr->router->rtaddr; 2405 if (sa6_recoverscope(s6)) { 2406 log(LOG_ERR, 2407 "scope error in " 2408 "prefix list (%s)\n", 2409 ip6_sprintf(ip6buf, 2410 &pfr->router->rtaddr)); 2411 } 2412 advrtrs++; 2413 } 2414 p->advrtrs = advrtrs; 2415 } else 2416 panic("buffer too short"); 2417 2418 advance = sizeof(*p) + sizeof(*sin6) * advrtrs; 2419 error = SYSCTL_OUT(req, buf, advance); 2420 if (error) 2421 break; 2422 } 2423 2424 return (error); 2425 } 2426