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 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/callout.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/socket.h> 44 #include <sys/sockio.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/protosw.h> 48 #include <sys/errno.h> 49 #include <sys/syslog.h> 50 #include <sys/lock.h> 51 #include <sys/rwlock.h> 52 #include <sys/queue.h> 53 #include <sys/sdt.h> 54 #include <sys/sysctl.h> 55 56 #include <net/if.h> 57 #include <net/if_var.h> 58 #include <net/if_arc.h> 59 #include <net/if_dl.h> 60 #include <net/if_types.h> 61 #include <net/iso88025.h> 62 #include <net/fddi.h> 63 #include <net/route.h> 64 #include <net/vnet.h> 65 66 #include <netinet/in.h> 67 #include <netinet/in_kdtrace.h> 68 #include <net/if_llatbl.h> 69 #include <netinet/if_ether.h> 70 #include <netinet6/in6_var.h> 71 #include <netinet/ip6.h> 72 #include <netinet6/ip6_var.h> 73 #include <netinet6/scope6_var.h> 74 #include <netinet6/nd6.h> 75 #include <netinet6/in6_ifattach.h> 76 #include <netinet/icmp6.h> 77 #include <netinet6/send.h> 78 79 #include <sys/limits.h> 80 81 #include <security/mac/mac_framework.h> 82 83 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ 84 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ 85 86 #define SIN6(s) ((const struct sockaddr_in6 *)(s)) 87 88 /* timer values */ 89 VNET_DEFINE(int, nd6_prune) = 1; /* walk list every 1 seconds */ 90 VNET_DEFINE(int, nd6_delay) = 5; /* delay first probe time 5 second */ 91 VNET_DEFINE(int, nd6_umaxtries) = 3; /* maximum unicast query */ 92 VNET_DEFINE(int, nd6_mmaxtries) = 3; /* maximum multicast query */ 93 VNET_DEFINE(int, nd6_useloopback) = 1; /* use loopback interface for 94 * local traffic */ 95 VNET_DEFINE(int, nd6_gctimer) = (60 * 60 * 24); /* 1 day: garbage 96 * collection timer */ 97 98 /* preventing too many loops in ND option parsing */ 99 static VNET_DEFINE(int, nd6_maxndopt) = 10; /* max # of ND options allowed */ 100 101 VNET_DEFINE(int, nd6_maxnudhint) = 0; /* max # of subsequent upper 102 * layer hints */ 103 static VNET_DEFINE(int, nd6_maxqueuelen) = 1; /* max pkts cached in unresolved 104 * ND entries */ 105 #define V_nd6_maxndopt VNET(nd6_maxndopt) 106 #define V_nd6_maxqueuelen VNET(nd6_maxqueuelen) 107 108 #ifdef ND6_DEBUG 109 VNET_DEFINE(int, nd6_debug) = 1; 110 #else 111 VNET_DEFINE(int, nd6_debug) = 0; 112 #endif 113 114 static eventhandler_tag lle_event_eh; 115 116 /* for debugging? */ 117 #if 0 118 static int nd6_inuse, nd6_allocated; 119 #endif 120 121 VNET_DEFINE(struct nd_drhead, nd_defrouter); 122 VNET_DEFINE(struct nd_prhead, nd_prefix); 123 124 VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL; 125 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) 126 127 int (*send_sendso_input_hook)(struct mbuf *, struct ifnet *, int, int); 128 129 static int nd6_is_new_addr_neighbor(const struct sockaddr_in6 *, 130 struct ifnet *); 131 static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *); 132 static void nd6_slowtimo(void *); 133 static int regen_tmpaddr(struct in6_ifaddr *); 134 static void nd6_free(struct llentry *, int); 135 static void nd6_free_redirect(const struct llentry *); 136 static void nd6_llinfo_timer(void *); 137 static void clear_llinfo_pqueue(struct llentry *); 138 static void nd6_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 139 static int nd6_resolve_slow(struct ifnet *, struct mbuf *, 140 const struct sockaddr_in6 *, u_char *, uint32_t *); 141 static int nd6_need_cache(struct ifnet *); 142 143 144 static VNET_DEFINE(struct callout, nd6_slowtimo_ch); 145 #define V_nd6_slowtimo_ch VNET(nd6_slowtimo_ch) 146 147 VNET_DEFINE(struct callout, nd6_timer_ch); 148 149 static void 150 nd6_lle_event(void *arg __unused, struct llentry *lle, int evt) 151 { 152 struct rt_addrinfo rtinfo; 153 struct sockaddr_in6 dst; 154 struct sockaddr_dl gw; 155 struct ifnet *ifp; 156 int type; 157 158 LLE_WLOCK_ASSERT(lle); 159 160 if (lltable_get_af(lle->lle_tbl) != AF_INET6) 161 return; 162 163 switch (evt) { 164 case LLENTRY_RESOLVED: 165 type = RTM_ADD; 166 KASSERT(lle->la_flags & LLE_VALID, 167 ("%s: %p resolved but not valid?", __func__, lle)); 168 break; 169 case LLENTRY_EXPIRED: 170 type = RTM_DELETE; 171 break; 172 default: 173 return; 174 } 175 176 ifp = lltable_get_ifp(lle->lle_tbl); 177 178 bzero(&dst, sizeof(dst)); 179 bzero(&gw, sizeof(gw)); 180 bzero(&rtinfo, sizeof(rtinfo)); 181 lltable_fill_sa_entry(lle, (struct sockaddr *)&dst); 182 dst.sin6_scope_id = in6_getscopezone(ifp, 183 in6_addrscope(&dst.sin6_addr)); 184 gw.sdl_len = sizeof(struct sockaddr_dl); 185 gw.sdl_family = AF_LINK; 186 gw.sdl_alen = ifp->if_addrlen; 187 gw.sdl_index = ifp->if_index; 188 gw.sdl_type = ifp->if_type; 189 if (evt == LLENTRY_RESOLVED) 190 bcopy(&lle->ll_addr, gw.sdl_data, ifp->if_addrlen); 191 rtinfo.rti_info[RTAX_DST] = (struct sockaddr *)&dst; 192 rtinfo.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&gw; 193 rtinfo.rti_addrs = RTA_DST | RTA_GATEWAY; 194 rt_missmsg_fib(type, &rtinfo, RTF_HOST | RTF_LLDATA | ( 195 type == RTM_ADD ? RTF_UP: 0), 0, RT_DEFAULT_FIB); 196 } 197 198 void 199 nd6_init(void) 200 { 201 202 LIST_INIT(&V_nd_prefix); 203 204 /* initialization of the default router list */ 205 TAILQ_INIT(&V_nd_defrouter); 206 207 /* start timer */ 208 callout_init(&V_nd6_slowtimo_ch, 0); 209 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 210 nd6_slowtimo, curvnet); 211 212 nd6_dad_init(); 213 if (IS_DEFAULT_VNET(curvnet)) 214 lle_event_eh = EVENTHANDLER_REGISTER(lle_event, nd6_lle_event, 215 NULL, EVENTHANDLER_PRI_ANY); 216 } 217 218 #ifdef VIMAGE 219 void 220 nd6_destroy() 221 { 222 223 callout_drain(&V_nd6_slowtimo_ch); 224 callout_drain(&V_nd6_timer_ch); 225 if (IS_DEFAULT_VNET(curvnet)) 226 EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh); 227 } 228 #endif 229 230 struct nd_ifinfo * 231 nd6_ifattach(struct ifnet *ifp) 232 { 233 struct nd_ifinfo *nd; 234 235 nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK|M_ZERO); 236 nd->initialized = 1; 237 238 nd->chlim = IPV6_DEFHLIM; 239 nd->basereachable = REACHABLE_TIME; 240 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 241 nd->retrans = RETRANS_TIMER; 242 243 nd->flags = ND6_IFF_PERFORMNUD; 244 245 /* A loopback interface always has ND6_IFF_AUTO_LINKLOCAL. 246 * XXXHRS: Clear ND6_IFF_AUTO_LINKLOCAL on an IFT_BRIDGE interface by 247 * default regardless of the V_ip6_auto_linklocal configuration to 248 * give a reasonable default behavior. 249 */ 250 if ((V_ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) || 251 (ifp->if_flags & IFF_LOOPBACK)) 252 nd->flags |= ND6_IFF_AUTO_LINKLOCAL; 253 /* 254 * A loopback interface does not need to accept RTADV. 255 * XXXHRS: Clear ND6_IFF_ACCEPT_RTADV on an IFT_BRIDGE interface by 256 * default regardless of the V_ip6_accept_rtadv configuration to 257 * prevent the interface from accepting RA messages arrived 258 * on one of the member interfaces with ND6_IFF_ACCEPT_RTADV. 259 */ 260 if (V_ip6_accept_rtadv && 261 !(ifp->if_flags & IFF_LOOPBACK) && 262 (ifp->if_type != IFT_BRIDGE)) 263 nd->flags |= ND6_IFF_ACCEPT_RTADV; 264 if (V_ip6_no_radr && !(ifp->if_flags & IFF_LOOPBACK)) 265 nd->flags |= ND6_IFF_NO_RADR; 266 267 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 268 nd6_setmtu0(ifp, nd); 269 270 return nd; 271 } 272 273 void 274 nd6_ifdetach(struct nd_ifinfo *nd) 275 { 276 277 free(nd, M_IP6NDP); 278 } 279 280 /* 281 * Reset ND level link MTU. This function is called when the physical MTU 282 * changes, which means we might have to adjust the ND level MTU. 283 */ 284 void 285 nd6_setmtu(struct ifnet *ifp) 286 { 287 288 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 289 } 290 291 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */ 292 void 293 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi) 294 { 295 u_int32_t omaxmtu; 296 297 omaxmtu = ndi->maxmtu; 298 299 switch (ifp->if_type) { 300 case IFT_ARCNET: 301 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */ 302 break; 303 case IFT_FDDI: 304 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); /* RFC2467 */ 305 break; 306 case IFT_ISO88025: 307 ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu); 308 break; 309 default: 310 ndi->maxmtu = ifp->if_mtu; 311 break; 312 } 313 314 /* 315 * Decreasing the interface MTU under IPV6 minimum MTU may cause 316 * undesirable situation. We thus notify the operator of the change 317 * explicitly. The check for omaxmtu is necessary to restrict the 318 * log to the case of changing the MTU, not initializing it. 319 */ 320 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 321 log(LOG_NOTICE, "nd6_setmtu0: " 322 "new link MTU on %s (%lu) is too small for IPv6\n", 323 if_name(ifp), (unsigned long)ndi->maxmtu); 324 } 325 326 if (ndi->maxmtu > V_in6_maxmtu) 327 in6_setmaxmtu(); /* check all interfaces just in case */ 328 329 } 330 331 void 332 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts) 333 { 334 335 bzero(ndopts, sizeof(*ndopts)); 336 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 337 ndopts->nd_opts_last 338 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 339 340 if (icmp6len == 0) { 341 ndopts->nd_opts_done = 1; 342 ndopts->nd_opts_search = NULL; 343 } 344 } 345 346 /* 347 * Take one ND option. 348 */ 349 struct nd_opt_hdr * 350 nd6_option(union nd_opts *ndopts) 351 { 352 struct nd_opt_hdr *nd_opt; 353 int olen; 354 355 KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__)); 356 KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts", 357 __func__)); 358 if (ndopts->nd_opts_search == NULL) 359 return NULL; 360 if (ndopts->nd_opts_done) 361 return NULL; 362 363 nd_opt = ndopts->nd_opts_search; 364 365 /* make sure nd_opt_len is inside the buffer */ 366 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { 367 bzero(ndopts, sizeof(*ndopts)); 368 return NULL; 369 } 370 371 olen = nd_opt->nd_opt_len << 3; 372 if (olen == 0) { 373 /* 374 * Message validation requires that all included 375 * options have a length that is greater than zero. 376 */ 377 bzero(ndopts, sizeof(*ndopts)); 378 return NULL; 379 } 380 381 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); 382 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 383 /* option overruns the end of buffer, invalid */ 384 bzero(ndopts, sizeof(*ndopts)); 385 return NULL; 386 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 387 /* reached the end of options chain */ 388 ndopts->nd_opts_done = 1; 389 ndopts->nd_opts_search = NULL; 390 } 391 return nd_opt; 392 } 393 394 /* 395 * Parse multiple ND options. 396 * This function is much easier to use, for ND routines that do not need 397 * multiple options of the same type. 398 */ 399 int 400 nd6_options(union nd_opts *ndopts) 401 { 402 struct nd_opt_hdr *nd_opt; 403 int i = 0; 404 405 KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__)); 406 KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts", 407 __func__)); 408 if (ndopts->nd_opts_search == NULL) 409 return 0; 410 411 while (1) { 412 nd_opt = nd6_option(ndopts); 413 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 414 /* 415 * Message validation requires that all included 416 * options have a length that is greater than zero. 417 */ 418 ICMP6STAT_INC(icp6s_nd_badopt); 419 bzero(ndopts, sizeof(*ndopts)); 420 return -1; 421 } 422 423 if (nd_opt == NULL) 424 goto skip1; 425 426 switch (nd_opt->nd_opt_type) { 427 case ND_OPT_SOURCE_LINKADDR: 428 case ND_OPT_TARGET_LINKADDR: 429 case ND_OPT_MTU: 430 case ND_OPT_REDIRECTED_HEADER: 431 case ND_OPT_NONCE: 432 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 433 nd6log((LOG_INFO, 434 "duplicated ND6 option found (type=%d)\n", 435 nd_opt->nd_opt_type)); 436 /* XXX bark? */ 437 } else { 438 ndopts->nd_opt_array[nd_opt->nd_opt_type] 439 = nd_opt; 440 } 441 break; 442 case ND_OPT_PREFIX_INFORMATION: 443 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 444 ndopts->nd_opt_array[nd_opt->nd_opt_type] 445 = nd_opt; 446 } 447 ndopts->nd_opts_pi_end = 448 (struct nd_opt_prefix_info *)nd_opt; 449 break; 450 /* What about ND_OPT_ROUTE_INFO? RFC 4191 */ 451 case ND_OPT_RDNSS: /* RFC 6106 */ 452 case ND_OPT_DNSSL: /* RFC 6106 */ 453 /* 454 * Silently ignore options we know and do not care about 455 * in the kernel. 456 */ 457 break; 458 default: 459 /* 460 * Unknown options must be silently ignored, 461 * to accomodate future extension to the protocol. 462 */ 463 nd6log((LOG_DEBUG, 464 "nd6_options: unsupported option %d - " 465 "option ignored\n", nd_opt->nd_opt_type)); 466 } 467 468 skip1: 469 i++; 470 if (i > V_nd6_maxndopt) { 471 ICMP6STAT_INC(icp6s_nd_toomanyopt); 472 nd6log((LOG_INFO, "too many loop in nd opt\n")); 473 break; 474 } 475 476 if (ndopts->nd_opts_done) 477 break; 478 } 479 480 return 0; 481 } 482 483 /* 484 * ND6 timer routine to handle ND6 entries 485 */ 486 void 487 nd6_llinfo_settimer_locked(struct llentry *ln, long tick) 488 { 489 int canceled; 490 491 LLE_WLOCK_ASSERT(ln); 492 493 if (tick < 0) { 494 ln->la_expire = 0; 495 ln->ln_ntick = 0; 496 canceled = callout_stop(&ln->lle_timer); 497 } else { 498 ln->la_expire = time_uptime + tick / hz; 499 LLE_ADDREF(ln); 500 if (tick > INT_MAX) { 501 ln->ln_ntick = tick - INT_MAX; 502 canceled = callout_reset(&ln->lle_timer, INT_MAX, 503 nd6_llinfo_timer, ln); 504 } else { 505 ln->ln_ntick = 0; 506 canceled = callout_reset(&ln->lle_timer, tick, 507 nd6_llinfo_timer, ln); 508 } 509 } 510 if (canceled) 511 LLE_REMREF(ln); 512 } 513 514 /* 515 * Gets source address of the first packet in hold queue 516 * and stores it in @src. 517 * Returns pointer to @src (if hold queue is not empty) or NULL. 518 * 519 */ 520 static struct in6_addr * 521 nd6_llinfo_get_holdsrc(struct llentry *ln, struct in6_addr *src) 522 { 523 struct ip6_hdr hdr; 524 struct mbuf *m; 525 526 if (ln->la_hold == NULL) 527 return (NULL); 528 529 /* 530 * assume every packet in la_hold has the same IP header 531 */ 532 m = ln->la_hold; 533 if (sizeof(hdr) < m->m_len) 534 return (NULL); 535 536 m_copydata(m, 0, sizeof(hdr), (caddr_t)&hdr); 537 *src = hdr.ip6_src; 538 539 return (src); 540 } 541 542 /* 543 * Switch @lle state to new state optionally arming timers. 544 */ 545 void 546 nd6_llinfo_setstate(struct llentry *lle, int newstate) 547 { 548 struct ifnet *ifp; 549 long delay; 550 551 delay = 0; 552 553 switch (newstate) { 554 case ND6_LLINFO_INCOMPLETE: 555 ifp = lle->lle_tbl->llt_ifp; 556 delay = (long)ND_IFINFO(ifp)->retrans * hz / 1000; 557 break; 558 case ND6_LLINFO_REACHABLE: 559 if (!ND6_LLINFO_PERMANENT(lle)) { 560 ifp = lle->lle_tbl->llt_ifp; 561 delay = (long)ND_IFINFO(ifp)->reachable * hz; 562 } 563 break; 564 case ND6_LLINFO_STALE: 565 delay = (long)V_nd6_gctimer * hz; 566 break; 567 case ND6_LLINFO_DELAY: 568 lle->la_asked = 0; 569 delay = (long)V_nd6_delay * hz; 570 break; 571 } 572 573 if (delay > 0) 574 nd6_llinfo_settimer_locked(lle, delay); 575 576 lle->ln_state = newstate; 577 } 578 579 580 void 581 nd6_llinfo_settimer(struct llentry *ln, long tick) 582 { 583 584 LLE_WLOCK(ln); 585 nd6_llinfo_settimer_locked(ln, tick); 586 LLE_WUNLOCK(ln); 587 } 588 589 static void 590 nd6_llinfo_timer(void *arg) 591 { 592 struct llentry *ln; 593 struct in6_addr *dst, *pdst, *psrc, src; 594 struct ifnet *ifp; 595 struct nd_ifinfo *ndi = NULL; 596 int send_ns; 597 598 KASSERT(arg != NULL, ("%s: arg NULL", __func__)); 599 ln = (struct llentry *)arg; 600 LLE_WLOCK(ln); 601 if (callout_pending(&ln->lle_timer)) { 602 /* 603 * Here we are a bit odd here in the treatment of 604 * active/pending. If the pending bit is set, it got 605 * rescheduled before I ran. The active 606 * bit we ignore, since if it was stopped 607 * in ll_tablefree() and was currently running 608 * it would have return 0 so the code would 609 * not have deleted it since the callout could 610 * not be stopped so we want to go through 611 * with the delete here now. If the callout 612 * was restarted, the pending bit will be back on and 613 * we just want to bail since the callout_reset would 614 * return 1 and our reference would have been removed 615 * by nd6_llinfo_settimer_locked above since canceled 616 * would have been 1. 617 */ 618 LLE_WUNLOCK(ln); 619 return; 620 } 621 ifp = ln->lle_tbl->llt_ifp; 622 CURVNET_SET(ifp->if_vnet); 623 ndi = ND_IFINFO(ifp); 624 send_ns = 0; 625 dst = &ln->r_l3addr.addr6; 626 pdst = dst; 627 628 if (ln->ln_ntick > 0) { 629 if (ln->ln_ntick > INT_MAX) { 630 ln->ln_ntick -= INT_MAX; 631 nd6_llinfo_settimer_locked(ln, INT_MAX); 632 } else { 633 ln->ln_ntick = 0; 634 nd6_llinfo_settimer_locked(ln, ln->ln_ntick); 635 } 636 goto done; 637 } 638 639 if (ln->la_flags & LLE_STATIC) { 640 goto done; 641 } 642 643 if (ln->la_flags & LLE_DELETED) { 644 nd6_free(ln, 0); 645 ln = NULL; 646 goto done; 647 } 648 649 switch (ln->ln_state) { 650 case ND6_LLINFO_INCOMPLETE: 651 if (ln->la_asked < V_nd6_mmaxtries) { 652 ln->la_asked++; 653 send_ns = 1; 654 /* Send NS to multicast address */ 655 pdst = NULL; 656 } else { 657 struct mbuf *m = ln->la_hold; 658 if (m) { 659 struct mbuf *m0; 660 661 /* 662 * assuming every packet in la_hold has the 663 * same IP header. Send error after unlock. 664 */ 665 m0 = m->m_nextpkt; 666 m->m_nextpkt = NULL; 667 ln->la_hold = m0; 668 clear_llinfo_pqueue(ln); 669 } 670 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_TIMEDOUT); 671 nd6_free(ln, 0); 672 ln = NULL; 673 if (m != NULL) 674 icmp6_error2(m, ICMP6_DST_UNREACH, 675 ICMP6_DST_UNREACH_ADDR, 0, ifp); 676 } 677 break; 678 case ND6_LLINFO_REACHABLE: 679 if (!ND6_LLINFO_PERMANENT(ln)) 680 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); 681 break; 682 683 case ND6_LLINFO_STALE: 684 /* Garbage Collection(RFC 2461 5.3) */ 685 if (!ND6_LLINFO_PERMANENT(ln)) { 686 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED); 687 nd6_free(ln, 1); 688 ln = NULL; 689 } 690 break; 691 692 case ND6_LLINFO_DELAY: 693 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 694 /* We need NUD */ 695 ln->la_asked = 1; 696 nd6_llinfo_setstate(ln, ND6_LLINFO_PROBE); 697 send_ns = 1; 698 } else 699 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); /* XXX */ 700 break; 701 case ND6_LLINFO_PROBE: 702 if (ln->la_asked < V_nd6_umaxtries) { 703 ln->la_asked++; 704 send_ns = 1; 705 } else { 706 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED); 707 nd6_free(ln, 0); 708 ln = NULL; 709 } 710 break; 711 default: 712 panic("%s: paths in a dark night can be confusing: %d", 713 __func__, ln->ln_state); 714 } 715 done: 716 if (send_ns != 0) { 717 nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); 718 psrc = nd6_llinfo_get_holdsrc(ln, &src); 719 LLE_FREE_LOCKED(ln); 720 ln = NULL; 721 nd6_ns_output(ifp, psrc, pdst, dst, NULL); 722 } 723 724 if (ln != NULL) 725 LLE_FREE_LOCKED(ln); 726 CURVNET_RESTORE(); 727 } 728 729 730 /* 731 * ND6 timer routine to expire default route list and prefix list 732 */ 733 void 734 nd6_timer(void *arg) 735 { 736 CURVNET_SET((struct vnet *) arg); 737 struct nd_defrouter *dr, *ndr; 738 struct nd_prefix *pr, *npr; 739 struct in6_ifaddr *ia6, *nia6; 740 741 callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz, 742 nd6_timer, curvnet); 743 744 /* expire default router list */ 745 TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) { 746 if (dr->expire && dr->expire < time_uptime) 747 defrtrlist_del(dr); 748 } 749 750 /* 751 * expire interface addresses. 752 * in the past the loop was inside prefix expiry processing. 753 * However, from a stricter speci-confrmance standpoint, we should 754 * rather separate address lifetimes and prefix lifetimes. 755 * 756 * XXXRW: in6_ifaddrhead locking. 757 */ 758 addrloop: 759 TAILQ_FOREACH_SAFE(ia6, &V_in6_ifaddrhead, ia_link, nia6) { 760 /* check address lifetime */ 761 if (IFA6_IS_INVALID(ia6)) { 762 int regen = 0; 763 764 /* 765 * If the expiring address is temporary, try 766 * regenerating a new one. This would be useful when 767 * we suspended a laptop PC, then turned it on after a 768 * period that could invalidate all temporary 769 * addresses. Although we may have to restart the 770 * loop (see below), it must be after purging the 771 * address. Otherwise, we'd see an infinite loop of 772 * regeneration. 773 */ 774 if (V_ip6_use_tempaddr && 775 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 776 if (regen_tmpaddr(ia6) == 0) 777 regen = 1; 778 } 779 780 in6_purgeaddr(&ia6->ia_ifa); 781 782 if (regen) 783 goto addrloop; /* XXX: see below */ 784 } else if (IFA6_IS_DEPRECATED(ia6)) { 785 int oldflags = ia6->ia6_flags; 786 787 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 788 789 /* 790 * If a temporary address has just become deprecated, 791 * regenerate a new one if possible. 792 */ 793 if (V_ip6_use_tempaddr && 794 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 795 (oldflags & IN6_IFF_DEPRECATED) == 0) { 796 797 if (regen_tmpaddr(ia6) == 0) { 798 /* 799 * A new temporary address is 800 * generated. 801 * XXX: this means the address chain 802 * has changed while we are still in 803 * the loop. Although the change 804 * would not cause disaster (because 805 * it's not a deletion, but an 806 * addition,) we'd rather restart the 807 * loop just for safety. Or does this 808 * significantly reduce performance?? 809 */ 810 goto addrloop; 811 } 812 } 813 } else { 814 /* 815 * A new RA might have made a deprecated address 816 * preferred. 817 */ 818 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 819 } 820 } 821 822 /* expire prefix list */ 823 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) { 824 /* 825 * check prefix lifetime. 826 * since pltime is just for autoconf, pltime processing for 827 * prefix is not necessary. 828 */ 829 if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && 830 time_uptime - pr->ndpr_lastupdate > pr->ndpr_vltime) { 831 832 /* 833 * address expiration and prefix expiration are 834 * separate. NEVER perform in6_purgeaddr here. 835 */ 836 prelist_remove(pr); 837 } 838 } 839 CURVNET_RESTORE(); 840 } 841 842 /* 843 * ia6 - deprecated/invalidated temporary address 844 */ 845 static int 846 regen_tmpaddr(struct in6_ifaddr *ia6) 847 { 848 struct ifaddr *ifa; 849 struct ifnet *ifp; 850 struct in6_ifaddr *public_ifa6 = NULL; 851 852 ifp = ia6->ia_ifa.ifa_ifp; 853 IF_ADDR_RLOCK(ifp); 854 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 855 struct in6_ifaddr *it6; 856 857 if (ifa->ifa_addr->sa_family != AF_INET6) 858 continue; 859 860 it6 = (struct in6_ifaddr *)ifa; 861 862 /* ignore no autoconf addresses. */ 863 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 864 continue; 865 866 /* ignore autoconf addresses with different prefixes. */ 867 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 868 continue; 869 870 /* 871 * Now we are looking at an autoconf address with the same 872 * prefix as ours. If the address is temporary and is still 873 * preferred, do not create another one. It would be rare, but 874 * could happen, for example, when we resume a laptop PC after 875 * a long period. 876 */ 877 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 878 !IFA6_IS_DEPRECATED(it6)) { 879 public_ifa6 = NULL; 880 break; 881 } 882 883 /* 884 * This is a public autoconf address that has the same prefix 885 * as ours. If it is preferred, keep it. We can't break the 886 * loop here, because there may be a still-preferred temporary 887 * address with the prefix. 888 */ 889 if (!IFA6_IS_DEPRECATED(it6)) 890 public_ifa6 = it6; 891 } 892 if (public_ifa6 != NULL) 893 ifa_ref(&public_ifa6->ia_ifa); 894 IF_ADDR_RUNLOCK(ifp); 895 896 if (public_ifa6 != NULL) { 897 int e; 898 899 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 900 ifa_free(&public_ifa6->ia_ifa); 901 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 902 " tmp addr,errno=%d\n", e); 903 return (-1); 904 } 905 ifa_free(&public_ifa6->ia_ifa); 906 return (0); 907 } 908 909 return (-1); 910 } 911 912 /* 913 * Nuke neighbor cache/prefix/default router management table, right before 914 * ifp goes away. 915 */ 916 void 917 nd6_purge(struct ifnet *ifp) 918 { 919 struct nd_defrouter *dr, *ndr; 920 struct nd_prefix *pr, *npr; 921 922 /* 923 * Nuke default router list entries toward ifp. 924 * We defer removal of default router list entries that is installed 925 * in the routing table, in order to keep additional side effects as 926 * small as possible. 927 */ 928 TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) { 929 if (dr->installed) 930 continue; 931 932 if (dr->ifp == ifp) 933 defrtrlist_del(dr); 934 } 935 936 TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) { 937 if (!dr->installed) 938 continue; 939 940 if (dr->ifp == ifp) 941 defrtrlist_del(dr); 942 } 943 944 /* Nuke prefix list entries toward ifp */ 945 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) { 946 if (pr->ndpr_ifp == ifp) { 947 /* 948 * Because if_detach() does *not* release prefixes 949 * while purging addresses the reference count will 950 * still be above zero. We therefore reset it to 951 * make sure that the prefix really gets purged. 952 */ 953 pr->ndpr_refcnt = 0; 954 955 /* 956 * Previously, pr->ndpr_addr is removed as well, 957 * but I strongly believe we don't have to do it. 958 * nd6_purge() is only called from in6_ifdetach(), 959 * which removes all the associated interface addresses 960 * by itself. 961 * (jinmei@kame.net 20010129) 962 */ 963 prelist_remove(pr); 964 } 965 } 966 967 /* cancel default outgoing interface setting */ 968 if (V_nd6_defifindex == ifp->if_index) 969 nd6_setdefaultiface(0); 970 971 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { 972 /* Refresh default router list. */ 973 defrouter_select(); 974 } 975 976 /* XXXXX 977 * We do not nuke the neighbor cache entries here any more 978 * because the neighbor cache is kept in if_afdata[AF_INET6]. 979 * nd6_purge() is invoked by in6_ifdetach() which is called 980 * from if_detach() where everything gets purged. So let 981 * in6_domifdetach() do the actual L2 table purging work. 982 */ 983 } 984 985 /* 986 * the caller acquires and releases the lock on the lltbls 987 * Returns the llentry locked 988 */ 989 struct llentry * 990 nd6_lookup(const struct in6_addr *addr6, int flags, struct ifnet *ifp) 991 { 992 struct sockaddr_in6 sin6; 993 struct llentry *ln; 994 995 bzero(&sin6, sizeof(sin6)); 996 sin6.sin6_len = sizeof(struct sockaddr_in6); 997 sin6.sin6_family = AF_INET6; 998 sin6.sin6_addr = *addr6; 999 1000 IF_AFDATA_LOCK_ASSERT(ifp); 1001 1002 ln = lla_lookup(LLTABLE6(ifp), flags, (struct sockaddr *)&sin6); 1003 1004 return (ln); 1005 } 1006 1007 struct llentry * 1008 nd6_alloc(const struct in6_addr *addr6, int flags, struct ifnet *ifp) 1009 { 1010 struct sockaddr_in6 sin6; 1011 struct llentry *ln; 1012 1013 bzero(&sin6, sizeof(sin6)); 1014 sin6.sin6_len = sizeof(struct sockaddr_in6); 1015 sin6.sin6_family = AF_INET6; 1016 sin6.sin6_addr = *addr6; 1017 1018 ln = lltable_alloc_entry(LLTABLE6(ifp), 0, (struct sockaddr *)&sin6); 1019 if (ln != NULL) 1020 ln->ln_state = ND6_LLINFO_NOSTATE; 1021 1022 return (ln); 1023 } 1024 1025 /* 1026 * Test whether a given IPv6 address is a neighbor or not, ignoring 1027 * the actual neighbor cache. The neighbor cache is ignored in order 1028 * to not reenter the routing code from within itself. 1029 */ 1030 static int 1031 nd6_is_new_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp) 1032 { 1033 struct nd_prefix *pr; 1034 struct ifaddr *dstaddr; 1035 1036 /* 1037 * A link-local address is always a neighbor. 1038 * XXX: a link does not necessarily specify a single interface. 1039 */ 1040 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 1041 struct sockaddr_in6 sin6_copy; 1042 u_int32_t zone; 1043 1044 /* 1045 * We need sin6_copy since sa6_recoverscope() may modify the 1046 * content (XXX). 1047 */ 1048 sin6_copy = *addr; 1049 if (sa6_recoverscope(&sin6_copy)) 1050 return (0); /* XXX: should be impossible */ 1051 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 1052 return (0); 1053 if (sin6_copy.sin6_scope_id == zone) 1054 return (1); 1055 else 1056 return (0); 1057 } 1058 1059 /* 1060 * If the address matches one of our addresses, 1061 * it should be a neighbor. 1062 * If the address matches one of our on-link prefixes, it should be a 1063 * neighbor. 1064 */ 1065 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1066 if (pr->ndpr_ifp != ifp) 1067 continue; 1068 1069 if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) { 1070 struct rtentry *rt; 1071 1072 /* Always use the default FIB here. */ 1073 rt = in6_rtalloc1((struct sockaddr *)&pr->ndpr_prefix, 1074 0, 0, RT_DEFAULT_FIB); 1075 if (rt == NULL) 1076 continue; 1077 /* 1078 * This is the case where multiple interfaces 1079 * have the same prefix, but only one is installed 1080 * into the routing table and that prefix entry 1081 * is not the one being examined here. In the case 1082 * where RADIX_MPATH is enabled, multiple route 1083 * entries (of the same rt_key value) will be 1084 * installed because the interface addresses all 1085 * differ. 1086 */ 1087 if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 1088 &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr)) { 1089 RTFREE_LOCKED(rt); 1090 continue; 1091 } 1092 RTFREE_LOCKED(rt); 1093 } 1094 1095 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 1096 &addr->sin6_addr, &pr->ndpr_mask)) 1097 return (1); 1098 } 1099 1100 /* 1101 * If the address is assigned on the node of the other side of 1102 * a p2p interface, the address should be a neighbor. 1103 */ 1104 dstaddr = ifa_ifwithdstaddr((const struct sockaddr *)addr, RT_ALL_FIBS); 1105 if (dstaddr != NULL) { 1106 if (dstaddr->ifa_ifp == ifp) { 1107 ifa_free(dstaddr); 1108 return (1); 1109 } 1110 ifa_free(dstaddr); 1111 } 1112 1113 /* 1114 * If the default router list is empty, all addresses are regarded 1115 * as on-link, and thus, as a neighbor. 1116 */ 1117 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && 1118 TAILQ_EMPTY(&V_nd_defrouter) && 1119 V_nd6_defifindex == ifp->if_index) { 1120 return (1); 1121 } 1122 1123 return (0); 1124 } 1125 1126 1127 /* 1128 * Detect if a given IPv6 address identifies a neighbor on a given link. 1129 * XXX: should take care of the destination of a p2p link? 1130 */ 1131 int 1132 nd6_is_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp) 1133 { 1134 struct llentry *lle; 1135 int rc = 0; 1136 1137 IF_AFDATA_UNLOCK_ASSERT(ifp); 1138 if (nd6_is_new_addr_neighbor(addr, ifp)) 1139 return (1); 1140 1141 /* 1142 * Even if the address matches none of our addresses, it might be 1143 * in the neighbor cache. 1144 */ 1145 IF_AFDATA_RLOCK(ifp); 1146 if ((lle = nd6_lookup(&addr->sin6_addr, 0, ifp)) != NULL) { 1147 LLE_RUNLOCK(lle); 1148 rc = 1; 1149 } 1150 IF_AFDATA_RUNLOCK(ifp); 1151 return (rc); 1152 } 1153 1154 /* 1155 * Free an nd6 llinfo entry. 1156 * Since the function would cause significant changes in the kernel, DO NOT 1157 * make it global, unless you have a strong reason for the change, and are sure 1158 * that the change is safe. 1159 */ 1160 static void 1161 nd6_free(struct llentry *ln, int gc) 1162 { 1163 struct nd_defrouter *dr; 1164 struct ifnet *ifp; 1165 1166 LLE_WLOCK_ASSERT(ln); 1167 1168 /* 1169 * we used to have pfctlinput(PRC_HOSTDEAD) here. 1170 * even though it is not harmful, it was not really necessary. 1171 */ 1172 1173 /* cancel timer */ 1174 nd6_llinfo_settimer_locked(ln, -1); 1175 1176 ifp = ln->lle_tbl->llt_ifp; 1177 1178 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { 1179 dr = defrouter_lookup(&ln->r_l3addr.addr6, ifp); 1180 1181 if (dr != NULL && dr->expire && 1182 ln->ln_state == ND6_LLINFO_STALE && gc) { 1183 /* 1184 * If the reason for the deletion is just garbage 1185 * collection, and the neighbor is an active default 1186 * router, do not delete it. Instead, reset the GC 1187 * timer using the router's lifetime. 1188 * Simply deleting the entry would affect default 1189 * router selection, which is not necessarily a good 1190 * thing, especially when we're using router preference 1191 * values. 1192 * XXX: the check for ln_state would be redundant, 1193 * but we intentionally keep it just in case. 1194 */ 1195 if (dr->expire > time_uptime) 1196 nd6_llinfo_settimer_locked(ln, 1197 (dr->expire - time_uptime) * hz); 1198 else 1199 nd6_llinfo_settimer_locked(ln, 1200 (long)V_nd6_gctimer * hz); 1201 1202 LLE_REMREF(ln); 1203 LLE_WUNLOCK(ln); 1204 return; 1205 } 1206 1207 if (dr) { 1208 /* 1209 * Unreachablity of a router might affect the default 1210 * router selection and on-link detection of advertised 1211 * prefixes. 1212 */ 1213 1214 /* 1215 * Temporarily fake the state to choose a new default 1216 * router and to perform on-link determination of 1217 * prefixes correctly. 1218 * Below the state will be set correctly, 1219 * or the entry itself will be deleted. 1220 */ 1221 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1222 } 1223 1224 if (ln->ln_router || dr) { 1225 1226 /* 1227 * We need to unlock to avoid a LOR with rt6_flush() with the 1228 * rnh and for the calls to pfxlist_onlink_check() and 1229 * defrouter_select() in the block further down for calls 1230 * into nd6_lookup(). We still hold a ref. 1231 */ 1232 LLE_WUNLOCK(ln); 1233 1234 /* 1235 * rt6_flush must be called whether or not the neighbor 1236 * is in the Default Router List. 1237 * See a corresponding comment in nd6_na_input(). 1238 */ 1239 rt6_flush(&ln->r_l3addr.addr6, ifp); 1240 } 1241 1242 if (dr) { 1243 /* 1244 * Since defrouter_select() does not affect the 1245 * on-link determination and MIP6 needs the check 1246 * before the default router selection, we perform 1247 * the check now. 1248 */ 1249 pfxlist_onlink_check(); 1250 1251 /* 1252 * Refresh default router list. 1253 */ 1254 defrouter_select(); 1255 } 1256 1257 /* 1258 * If this entry was added by an on-link redirect, remove the 1259 * corresponding host route. 1260 */ 1261 if (ln->la_flags & LLE_REDIRECT) 1262 nd6_free_redirect(ln); 1263 1264 if (ln->ln_router || dr) 1265 LLE_WLOCK(ln); 1266 } 1267 1268 /* 1269 * Save to unlock. We still hold an extra reference and will not 1270 * free(9) in llentry_free() if someone else holds one as well. 1271 */ 1272 LLE_WUNLOCK(ln); 1273 IF_AFDATA_LOCK(ifp); 1274 LLE_WLOCK(ln); 1275 /* Guard against race with other llentry_free(). */ 1276 if (ln->la_flags & LLE_LINKED) { 1277 /* Remove callout reference */ 1278 LLE_REMREF(ln); 1279 lltable_unlink_entry(ln->lle_tbl, ln); 1280 } 1281 IF_AFDATA_UNLOCK(ifp); 1282 1283 llentry_free(ln); 1284 } 1285 1286 /* 1287 * Remove the rtentry for the given llentry, 1288 * both of which were installed by a redirect. 1289 */ 1290 static void 1291 nd6_free_redirect(const struct llentry *ln) 1292 { 1293 int fibnum; 1294 struct rtentry *rt; 1295 struct radix_node_head *rnh; 1296 struct sockaddr_in6 sin6; 1297 1298 lltable_fill_sa_entry(ln, (struct sockaddr *)&sin6); 1299 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) { 1300 rnh = rt_tables_get_rnh(fibnum, AF_INET6); 1301 if (rnh == NULL) 1302 continue; 1303 1304 RADIX_NODE_HEAD_LOCK(rnh); 1305 rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 1306 RTF_RNH_LOCKED, fibnum); 1307 if (rt) { 1308 if (rt->rt_flags == (RTF_UP | RTF_HOST | RTF_DYNAMIC)) 1309 rt_expunge(rnh, rt); 1310 RTFREE_LOCKED(rt); 1311 } 1312 RADIX_NODE_HEAD_UNLOCK(rnh); 1313 } 1314 } 1315 1316 /* 1317 * Upper-layer reachability hint for Neighbor Unreachability Detection. 1318 * 1319 * XXX cost-effective methods? 1320 */ 1321 void 1322 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force) 1323 { 1324 struct llentry *ln; 1325 struct ifnet *ifp; 1326 1327 if ((dst6 == NULL) || (rt == NULL)) 1328 return; 1329 1330 ifp = rt->rt_ifp; 1331 IF_AFDATA_RLOCK(ifp); 1332 ln = nd6_lookup(dst6, LLE_EXCLUSIVE, NULL); 1333 IF_AFDATA_RUNLOCK(ifp); 1334 if (ln == NULL) 1335 return; 1336 1337 if (ln->ln_state < ND6_LLINFO_REACHABLE) 1338 goto done; 1339 1340 /* 1341 * if we get upper-layer reachability confirmation many times, 1342 * it is possible we have false information. 1343 */ 1344 if (!force) { 1345 ln->ln_byhint++; 1346 if (ln->ln_byhint > V_nd6_maxnudhint) { 1347 goto done; 1348 } 1349 } 1350 1351 nd6_llinfo_setstate(ln, ND6_LLINFO_REACHABLE); 1352 done: 1353 LLE_WUNLOCK(ln); 1354 } 1355 1356 1357 /* 1358 * Rejuvenate this function for routing operations related 1359 * processing. 1360 */ 1361 void 1362 nd6_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info) 1363 { 1364 struct sockaddr_in6 *gateway; 1365 struct nd_defrouter *dr; 1366 struct ifnet *ifp; 1367 1368 gateway = (struct sockaddr_in6 *)rt->rt_gateway; 1369 ifp = rt->rt_ifp; 1370 1371 switch (req) { 1372 case RTM_ADD: 1373 break; 1374 1375 case RTM_DELETE: 1376 if (!ifp) 1377 return; 1378 /* 1379 * Only indirect routes are interesting. 1380 */ 1381 if ((rt->rt_flags & RTF_GATEWAY) == 0) 1382 return; 1383 /* 1384 * check for default route 1385 */ 1386 if (IN6_ARE_ADDR_EQUAL(&in6addr_any, 1387 &SIN6(rt_key(rt))->sin6_addr)) { 1388 1389 dr = defrouter_lookup(&gateway->sin6_addr, ifp); 1390 if (dr != NULL) 1391 dr->installed = 0; 1392 } 1393 break; 1394 } 1395 } 1396 1397 1398 int 1399 nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) 1400 { 1401 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1402 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1403 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1404 int error = 0; 1405 1406 if (ifp->if_afdata[AF_INET6] == NULL) 1407 return (EPFNOSUPPORT); 1408 switch (cmd) { 1409 case OSIOCGIFINFO_IN6: 1410 #define ND ndi->ndi 1411 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1412 bzero(&ND, sizeof(ND)); 1413 ND.linkmtu = IN6_LINKMTU(ifp); 1414 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1415 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1416 ND.reachable = ND_IFINFO(ifp)->reachable; 1417 ND.retrans = ND_IFINFO(ifp)->retrans; 1418 ND.flags = ND_IFINFO(ifp)->flags; 1419 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1420 ND.chlim = ND_IFINFO(ifp)->chlim; 1421 break; 1422 case SIOCGIFINFO_IN6: 1423 ND = *ND_IFINFO(ifp); 1424 break; 1425 case SIOCSIFINFO_IN6: 1426 /* 1427 * used to change host variables from userland. 1428 * intented for a use on router to reflect RA configurations. 1429 */ 1430 /* 0 means 'unspecified' */ 1431 if (ND.linkmtu != 0) { 1432 if (ND.linkmtu < IPV6_MMTU || 1433 ND.linkmtu > IN6_LINKMTU(ifp)) { 1434 error = EINVAL; 1435 break; 1436 } 1437 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1438 } 1439 1440 if (ND.basereachable != 0) { 1441 int obasereachable = ND_IFINFO(ifp)->basereachable; 1442 1443 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1444 if (ND.basereachable != obasereachable) 1445 ND_IFINFO(ifp)->reachable = 1446 ND_COMPUTE_RTIME(ND.basereachable); 1447 } 1448 if (ND.retrans != 0) 1449 ND_IFINFO(ifp)->retrans = ND.retrans; 1450 if (ND.chlim != 0) 1451 ND_IFINFO(ifp)->chlim = ND.chlim; 1452 /* FALLTHROUGH */ 1453 case SIOCSIFINFO_FLAGS: 1454 { 1455 struct ifaddr *ifa; 1456 struct in6_ifaddr *ia; 1457 1458 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && 1459 !(ND.flags & ND6_IFF_IFDISABLED)) { 1460 /* ifdisabled 1->0 transision */ 1461 1462 /* 1463 * If the interface is marked as ND6_IFF_IFDISABLED and 1464 * has an link-local address with IN6_IFF_DUPLICATED, 1465 * do not clear ND6_IFF_IFDISABLED. 1466 * See RFC 4862, Section 5.4.5. 1467 */ 1468 IF_ADDR_RLOCK(ifp); 1469 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1470 if (ifa->ifa_addr->sa_family != AF_INET6) 1471 continue; 1472 ia = (struct in6_ifaddr *)ifa; 1473 if ((ia->ia6_flags & IN6_IFF_DUPLICATED) && 1474 IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) 1475 break; 1476 } 1477 IF_ADDR_RUNLOCK(ifp); 1478 1479 if (ifa != NULL) { 1480 /* LLA is duplicated. */ 1481 ND.flags |= ND6_IFF_IFDISABLED; 1482 log(LOG_ERR, "Cannot enable an interface" 1483 " with a link-local address marked" 1484 " duplicate.\n"); 1485 } else { 1486 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IFDISABLED; 1487 if (ifp->if_flags & IFF_UP) 1488 in6_if_up(ifp); 1489 } 1490 } else if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && 1491 (ND.flags & ND6_IFF_IFDISABLED)) { 1492 /* ifdisabled 0->1 transision */ 1493 /* Mark all IPv6 address as tentative. */ 1494 1495 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1496 if ((ND_IFINFO(ifp)->flags & ND6_IFF_NO_DAD) == 0) { 1497 IF_ADDR_RLOCK(ifp); 1498 TAILQ_FOREACH(ifa, &ifp->if_addrhead, 1499 ifa_link) { 1500 if (ifa->ifa_addr->sa_family != 1501 AF_INET6) 1502 continue; 1503 ia = (struct in6_ifaddr *)ifa; 1504 ia->ia6_flags |= IN6_IFF_TENTATIVE; 1505 } 1506 IF_ADDR_RUNLOCK(ifp); 1507 } 1508 } 1509 1510 if (ND.flags & ND6_IFF_AUTO_LINKLOCAL) { 1511 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL)) { 1512 /* auto_linklocal 0->1 transision */ 1513 1514 /* If no link-local address on ifp, configure */ 1515 ND_IFINFO(ifp)->flags |= ND6_IFF_AUTO_LINKLOCAL; 1516 in6_ifattach(ifp, NULL); 1517 } else if (!(ND.flags & ND6_IFF_IFDISABLED) && 1518 ifp->if_flags & IFF_UP) { 1519 /* 1520 * When the IF already has 1521 * ND6_IFF_AUTO_LINKLOCAL, no link-local 1522 * address is assigned, and IFF_UP, try to 1523 * assign one. 1524 */ 1525 IF_ADDR_RLOCK(ifp); 1526 TAILQ_FOREACH(ifa, &ifp->if_addrhead, 1527 ifa_link) { 1528 if (ifa->ifa_addr->sa_family != 1529 AF_INET6) 1530 continue; 1531 ia = (struct in6_ifaddr *)ifa; 1532 if (IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) 1533 break; 1534 } 1535 IF_ADDR_RUNLOCK(ifp); 1536 if (ifa != NULL) 1537 /* No LLA is configured. */ 1538 in6_ifattach(ifp, NULL); 1539 } 1540 } 1541 } 1542 ND_IFINFO(ifp)->flags = ND.flags; 1543 break; 1544 #undef ND 1545 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1546 /* sync kernel routing table with the default router list */ 1547 defrouter_reset(); 1548 defrouter_select(); 1549 break; 1550 case SIOCSPFXFLUSH_IN6: 1551 { 1552 /* flush all the prefix advertised by routers */ 1553 struct nd_prefix *pr, *next; 1554 1555 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) { 1556 struct in6_ifaddr *ia, *ia_next; 1557 1558 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1559 continue; /* XXX */ 1560 1561 /* do we really have to remove addresses as well? */ 1562 /* XXXRW: in6_ifaddrhead locking. */ 1563 TAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link, 1564 ia_next) { 1565 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1566 continue; 1567 1568 if (ia->ia6_ndpr == pr) 1569 in6_purgeaddr(&ia->ia_ifa); 1570 } 1571 prelist_remove(pr); 1572 } 1573 break; 1574 } 1575 case SIOCSRTRFLUSH_IN6: 1576 { 1577 /* flush all the default routers */ 1578 struct nd_defrouter *dr, *next; 1579 1580 defrouter_reset(); 1581 TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, next) { 1582 defrtrlist_del(dr); 1583 } 1584 defrouter_select(); 1585 break; 1586 } 1587 case SIOCGNBRINFO_IN6: 1588 { 1589 struct llentry *ln; 1590 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1591 1592 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1593 return (error); 1594 1595 IF_AFDATA_RLOCK(ifp); 1596 ln = nd6_lookup(&nb_addr, 0, ifp); 1597 IF_AFDATA_RUNLOCK(ifp); 1598 1599 if (ln == NULL) { 1600 error = EINVAL; 1601 break; 1602 } 1603 nbi->state = ln->ln_state; 1604 nbi->asked = ln->la_asked; 1605 nbi->isrouter = ln->ln_router; 1606 if (ln->la_expire == 0) 1607 nbi->expire = 0; 1608 else 1609 nbi->expire = ln->la_expire + 1610 (time_second - time_uptime); 1611 LLE_RUNLOCK(ln); 1612 break; 1613 } 1614 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1615 ndif->ifindex = V_nd6_defifindex; 1616 break; 1617 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1618 return (nd6_setdefaultiface(ndif->ifindex)); 1619 } 1620 return (error); 1621 } 1622 1623 /* 1624 * Calculates new isRouter value based on provided parameters and 1625 * returns it. 1626 */ 1627 static int 1628 nd6_is_router(int type, int code, int is_new, int old_addr, int new_addr, 1629 int ln_router) 1630 { 1631 1632 /* 1633 * ICMP6 type dependent behavior. 1634 * 1635 * NS: clear IsRouter if new entry 1636 * RS: clear IsRouter 1637 * RA: set IsRouter if there's lladdr 1638 * redir: clear IsRouter if new entry 1639 * 1640 * RA case, (1): 1641 * The spec says that we must set IsRouter in the following cases: 1642 * - If lladdr exist, set IsRouter. This means (1-5). 1643 * - If it is old entry (!newentry), set IsRouter. This means (7). 1644 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1645 * A quetion arises for (1) case. (1) case has no lladdr in the 1646 * neighbor cache, this is similar to (6). 1647 * This case is rare but we figured that we MUST NOT set IsRouter. 1648 * 1649 * is_new old_addr new_addr NS RS RA redir 1650 * D R 1651 * 0 n n (1) c ? s 1652 * 0 y n (2) c s s 1653 * 0 n y (3) c s s 1654 * 0 y y (4) c s s 1655 * 0 y y (5) c s s 1656 * 1 -- n (6) c c c s 1657 * 1 -- y (7) c c s c s 1658 * 1659 * (c=clear s=set) 1660 */ 1661 switch (type & 0xff) { 1662 case ND_NEIGHBOR_SOLICIT: 1663 /* 1664 * New entry must have is_router flag cleared. 1665 */ 1666 if (is_new) /* (6-7) */ 1667 ln_router = 0; 1668 break; 1669 case ND_REDIRECT: 1670 /* 1671 * If the icmp is a redirect to a better router, always set the 1672 * is_router flag. Otherwise, if the entry is newly created, 1673 * clear the flag. [RFC 2461, sec 8.3] 1674 */ 1675 if (code == ND_REDIRECT_ROUTER) 1676 ln_router = 1; 1677 else { 1678 if (is_new) /* (6-7) */ 1679 ln_router = 0; 1680 } 1681 break; 1682 case ND_ROUTER_SOLICIT: 1683 /* 1684 * is_router flag must always be cleared. 1685 */ 1686 ln_router = 0; 1687 break; 1688 case ND_ROUTER_ADVERT: 1689 /* 1690 * Mark an entry with lladdr as a router. 1691 */ 1692 if ((!is_new && (old_addr || new_addr)) || /* (2-5) */ 1693 (is_new && new_addr)) { /* (7) */ 1694 ln_router = 1; 1695 } 1696 break; 1697 } 1698 1699 return (ln_router); 1700 } 1701 1702 /* 1703 * Create neighbor cache entry and cache link-layer address, 1704 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1705 * 1706 * type - ICMP6 type 1707 * code - type dependent information 1708 * 1709 */ 1710 void 1711 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr, 1712 int lladdrlen, int type, int code) 1713 { 1714 struct llentry *ln = NULL, *ln_tmp; 1715 int is_newentry; 1716 int do_update; 1717 int olladdr; 1718 int llchange; 1719 int flags; 1720 uint16_t router = 0; 1721 struct sockaddr_in6 sin6; 1722 struct mbuf *chain = NULL; 1723 1724 IF_AFDATA_UNLOCK_ASSERT(ifp); 1725 1726 KASSERT(ifp != NULL, ("%s: ifp == NULL", __func__)); 1727 KASSERT(from != NULL, ("%s: from == NULL", __func__)); 1728 1729 /* nothing must be updated for unspecified address */ 1730 if (IN6_IS_ADDR_UNSPECIFIED(from)) 1731 return; 1732 1733 /* 1734 * Validation about ifp->if_addrlen and lladdrlen must be done in 1735 * the caller. 1736 * 1737 * XXX If the link does not have link-layer adderss, what should 1738 * we do? (ifp->if_addrlen == 0) 1739 * Spec says nothing in sections for RA, RS and NA. There's small 1740 * description on it in NS section (RFC 2461 7.2.3). 1741 */ 1742 flags = lladdr ? LLE_EXCLUSIVE : 0; 1743 IF_AFDATA_RLOCK(ifp); 1744 ln = nd6_lookup(from, flags, ifp); 1745 IF_AFDATA_RUNLOCK(ifp); 1746 is_newentry = 0; 1747 if (ln == NULL) { 1748 flags |= LLE_EXCLUSIVE; 1749 ln = nd6_alloc(from, 0, ifp); 1750 if (ln == NULL) 1751 return; 1752 1753 /* 1754 * Since we already know all the data for the new entry, 1755 * fill it before insertion. 1756 */ 1757 if (lladdr != NULL) { 1758 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 1759 ln->la_flags |= LLE_VALID; 1760 } 1761 IF_AFDATA_WLOCK(ifp); 1762 LLE_WLOCK(ln); 1763 /* Prefer any existing lle over newly-created one */ 1764 ln_tmp = nd6_lookup(from, LLE_EXCLUSIVE, ifp); 1765 if (ln_tmp == NULL) 1766 lltable_link_entry(LLTABLE6(ifp), ln); 1767 IF_AFDATA_WUNLOCK(ifp); 1768 if (ln_tmp == NULL) { 1769 /* No existing lle, mark as new entry */ 1770 is_newentry = 1; 1771 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); 1772 } else { 1773 lltable_free_entry(LLTABLE6(ifp), ln); 1774 ln = ln_tmp; 1775 ln_tmp = NULL; 1776 } 1777 } 1778 /* do nothing if static ndp is set */ 1779 if ((ln->la_flags & LLE_STATIC)) { 1780 if (flags & LLE_EXCLUSIVE) 1781 LLE_WUNLOCK(ln); 1782 else 1783 LLE_RUNLOCK(ln); 1784 return; 1785 } 1786 1787 olladdr = (ln->la_flags & LLE_VALID) ? 1 : 0; 1788 if (olladdr && lladdr) { 1789 llchange = bcmp(lladdr, &ln->ll_addr, 1790 ifp->if_addrlen); 1791 } else if (!olladdr && lladdr) 1792 llchange = 1; 1793 else 1794 llchange = 0; 1795 1796 /* 1797 * newentry olladdr lladdr llchange (*=record) 1798 * 0 n n -- (1) 1799 * 0 y n -- (2) 1800 * 0 n y y (3) * STALE 1801 * 0 y y n (4) * 1802 * 0 y y y (5) * STALE 1803 * 1 -- n -- (6) NOSTATE(= PASSIVE) 1804 * 1 -- y -- (7) * STALE 1805 */ 1806 1807 do_update = 0; 1808 if (!is_newentry && llchange != 0) 1809 do_update = 1; /* (3,5) */ 1810 1811 if (lladdr) { /* (3-5) and (7) */ 1812 /* 1813 * Record source link-layer address 1814 * XXX is it dependent to ifp->if_type? 1815 */ 1816 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 1817 ln->la_flags |= LLE_VALID; 1818 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); 1819 1820 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 1821 1822 if (do_update) { 1823 if (ln->la_hold != NULL) 1824 nd6_grab_holdchain(ln, &chain, &sin6); 1825 } 1826 } 1827 1828 /* Calculates new router status */ 1829 router = nd6_is_router(type, code, is_newentry, olladdr, 1830 lladdr != NULL ? 1 : 0, ln->ln_router); 1831 1832 ln->ln_router = router; 1833 /* Mark non-router redirects with special flag */ 1834 if ((type & 0xFF) == ND_REDIRECT && code != ND_REDIRECT_ROUTER) 1835 ln->la_flags |= LLE_REDIRECT; 1836 1837 if (flags & LLE_EXCLUSIVE) 1838 LLE_WUNLOCK(ln); 1839 else 1840 LLE_RUNLOCK(ln); 1841 1842 if (chain != NULL) 1843 nd6_flush_holdchain(ifp, ifp, chain, &sin6); 1844 1845 /* 1846 * When the link-layer address of a router changes, select the 1847 * best router again. In particular, when the neighbor entry is newly 1848 * created, it might affect the selection policy. 1849 * Question: can we restrict the first condition to the "is_newentry" 1850 * case? 1851 * XXX: when we hear an RA from a new router with the link-layer 1852 * address option, defrouter_select() is called twice, since 1853 * defrtrlist_update called the function as well. However, I believe 1854 * we can compromise the overhead, since it only happens the first 1855 * time. 1856 * XXX: although defrouter_select() should not have a bad effect 1857 * for those are not autoconfigured hosts, we explicitly avoid such 1858 * cases for safety. 1859 */ 1860 if ((do_update || is_newentry) && router && 1861 ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { 1862 /* 1863 * guaranteed recursion 1864 */ 1865 defrouter_select(); 1866 } 1867 } 1868 1869 static void 1870 nd6_slowtimo(void *arg) 1871 { 1872 CURVNET_SET((struct vnet *) arg); 1873 struct nd_ifinfo *nd6if; 1874 struct ifnet *ifp; 1875 1876 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 1877 nd6_slowtimo, curvnet); 1878 IFNET_RLOCK_NOSLEEP(); 1879 TAILQ_FOREACH(ifp, &V_ifnet, if_link) { 1880 if (ifp->if_afdata[AF_INET6] == NULL) 1881 continue; 1882 nd6if = ND_IFINFO(ifp); 1883 if (nd6if->basereachable && /* already initialized */ 1884 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 1885 /* 1886 * Since reachable time rarely changes by router 1887 * advertisements, we SHOULD insure that a new random 1888 * value gets recomputed at least once every few hours. 1889 * (RFC 2461, 6.3.4) 1890 */ 1891 nd6if->recalctm = V_nd6_recalc_reachtm_interval; 1892 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 1893 } 1894 } 1895 IFNET_RUNLOCK_NOSLEEP(); 1896 CURVNET_RESTORE(); 1897 } 1898 1899 void 1900 nd6_grab_holdchain(struct llentry *ln, struct mbuf **chain, 1901 struct sockaddr_in6 *sin6) 1902 { 1903 1904 LLE_WLOCK_ASSERT(ln); 1905 1906 *chain = ln->la_hold; 1907 ln->la_hold = NULL; 1908 lltable_fill_sa_entry(ln, (struct sockaddr *)sin6); 1909 1910 if (ln->ln_state == ND6_LLINFO_STALE) { 1911 1912 /* 1913 * The first time we send a packet to a 1914 * neighbor whose entry is STALE, we have 1915 * to change the state to DELAY and a sets 1916 * a timer to expire in DELAY_FIRST_PROBE_TIME 1917 * seconds to ensure do neighbor unreachability 1918 * detection on expiration. 1919 * (RFC 2461 7.3.3) 1920 */ 1921 nd6_llinfo_setstate(ln, ND6_LLINFO_DELAY); 1922 } 1923 } 1924 1925 int 1926 nd6_output_ifp(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m, 1927 struct sockaddr_in6 *dst) 1928 { 1929 int error; 1930 int ip6len; 1931 struct ip6_hdr *ip6; 1932 struct m_tag *mtag; 1933 1934 #ifdef MAC 1935 mac_netinet6_nd6_send(ifp, m); 1936 #endif 1937 1938 /* 1939 * If called from nd6_ns_output() (NS), nd6_na_output() (NA), 1940 * icmp6_redirect_output() (REDIRECT) or from rip6_output() (RS, RA 1941 * as handled by rtsol and rtadvd), mbufs will be tagged for SeND 1942 * to be diverted to user space. When re-injected into the kernel, 1943 * send_output() will directly dispatch them to the outgoing interface. 1944 */ 1945 if (send_sendso_input_hook != NULL) { 1946 mtag = m_tag_find(m, PACKET_TAG_ND_OUTGOING, NULL); 1947 if (mtag != NULL) { 1948 ip6 = mtod(m, struct ip6_hdr *); 1949 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen); 1950 /* Use the SEND socket */ 1951 error = send_sendso_input_hook(m, ifp, SND_OUT, 1952 ip6len); 1953 /* -1 == no app on SEND socket */ 1954 if (error == 0 || error != -1) 1955 return (error); 1956 } 1957 } 1958 1959 m_clrprotoflags(m); /* Avoid confusing lower layers. */ 1960 IP_PROBE(send, NULL, NULL, mtod(m, struct ip6_hdr *), ifp, NULL, 1961 mtod(m, struct ip6_hdr *)); 1962 1963 if ((ifp->if_flags & IFF_LOOPBACK) == 0) 1964 origifp = ifp; 1965 1966 error = (*ifp->if_output)(origifp, m, (struct sockaddr *)dst, NULL); 1967 return (error); 1968 } 1969 1970 /* 1971 * Do L2 address resolution for @sa_dst address. Stores found 1972 * address in @desten buffer. Copy of lle ln_flags can be also 1973 * saved in @pflags if @pflags is non-NULL. 1974 * 1975 * If destination LLE does not exists or lle state modification 1976 * is required, call "slow" version. 1977 * 1978 * Return values: 1979 * - 0 on success (address copied to buffer). 1980 * - EWOULDBLOCK (no local error, but address is still unresolved) 1981 * - other errors (alloc failure, etc) 1982 */ 1983 int 1984 nd6_resolve(struct ifnet *ifp, int is_gw, struct mbuf *m, 1985 const struct sockaddr *sa_dst, u_char *desten, uint32_t *pflags) 1986 { 1987 struct llentry *ln = NULL; 1988 const struct sockaddr_in6 *dst6; 1989 1990 if (pflags != NULL) 1991 *pflags = 0; 1992 1993 dst6 = (const struct sockaddr_in6 *)sa_dst; 1994 1995 /* discard the packet if IPv6 operation is disabled on the interface */ 1996 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 1997 m_freem(m); 1998 return (ENETDOWN); /* better error? */ 1999 } 2000 2001 if (m != NULL && m->m_flags & M_MCAST) { 2002 switch (ifp->if_type) { 2003 case IFT_ETHER: 2004 case IFT_FDDI: 2005 case IFT_L2VLAN: 2006 case IFT_IEEE80211: 2007 case IFT_BRIDGE: 2008 case IFT_ISO88025: 2009 ETHER_MAP_IPV6_MULTICAST(&dst6->sin6_addr, 2010 desten); 2011 return (0); 2012 default: 2013 m_freem(m); 2014 return (EAFNOSUPPORT); 2015 } 2016 } 2017 2018 IF_AFDATA_RLOCK(ifp); 2019 ln = nd6_lookup(&dst6->sin6_addr, 0, ifp); 2020 IF_AFDATA_RUNLOCK(ifp); 2021 2022 /* 2023 * Perform fast path for the following cases: 2024 * 1) lle state is REACHABLE 2025 * 2) lle state is DELAY (NS message sent) 2026 * 2027 * Every other case involves lle modification, so we handle 2028 * them separately. 2029 */ 2030 if (ln == NULL || (ln->ln_state != ND6_LLINFO_REACHABLE && 2031 ln->ln_state != ND6_LLINFO_DELAY)) { 2032 /* Fall back to slow processing path */ 2033 if (ln != NULL) 2034 LLE_RUNLOCK(ln); 2035 return (nd6_resolve_slow(ifp, m, dst6, desten, pflags)); 2036 } 2037 2038 2039 bcopy(&ln->ll_addr, desten, ifp->if_addrlen); 2040 if (pflags != NULL) 2041 *pflags = ln->la_flags; 2042 LLE_RUNLOCK(ln); 2043 return (0); 2044 } 2045 2046 2047 /* 2048 * Do L2 address resolution for @sa_dst address. Stores found 2049 * address in @desten buffer. Copy of lle ln_flags can be also 2050 * saved in @pflags if @pflags is non-NULL. 2051 * 2052 * Heavy version. 2053 * Function assume that destination LLE does not exist, 2054 * is invalid or stale, so LLE_EXCLUSIVE lock needs to be acquired. 2055 */ 2056 static int 2057 nd6_resolve_slow(struct ifnet *ifp, struct mbuf *m, 2058 const struct sockaddr_in6 *dst, u_char *desten, uint32_t *pflags) 2059 { 2060 struct llentry *lle = NULL, *lle_tmp; 2061 struct in6_addr *psrc, src; 2062 int send_ns; 2063 2064 /* 2065 * Address resolution or Neighbor Unreachability Detection 2066 * for the next hop. 2067 * At this point, the destination of the packet must be a unicast 2068 * or an anycast address(i.e. not a multicast). 2069 */ 2070 if (lle == NULL) { 2071 IF_AFDATA_RLOCK(ifp); 2072 lle = nd6_lookup(&dst->sin6_addr, LLE_EXCLUSIVE, ifp); 2073 IF_AFDATA_RUNLOCK(ifp); 2074 if ((lle == NULL) && nd6_is_addr_neighbor(dst, ifp)) { 2075 /* 2076 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 2077 * the condition below is not very efficient. But we believe 2078 * it is tolerable, because this should be a rare case. 2079 */ 2080 lle = nd6_alloc(&dst->sin6_addr, 0, ifp); 2081 if (lle == NULL) { 2082 char ip6buf[INET6_ADDRSTRLEN]; 2083 log(LOG_DEBUG, 2084 "nd6_output: can't allocate llinfo for %s " 2085 "(ln=%p)\n", 2086 ip6_sprintf(ip6buf, &dst->sin6_addr), lle); 2087 m_freem(m); 2088 return (ENOBUFS); 2089 } 2090 2091 IF_AFDATA_WLOCK(ifp); 2092 LLE_WLOCK(lle); 2093 /* Prefer any existing entry over newly-created one */ 2094 lle_tmp = nd6_lookup(&dst->sin6_addr, LLE_EXCLUSIVE, ifp); 2095 if (lle_tmp == NULL) 2096 lltable_link_entry(LLTABLE6(ifp), lle); 2097 IF_AFDATA_WUNLOCK(ifp); 2098 if (lle_tmp != NULL) { 2099 lltable_free_entry(LLTABLE6(ifp), lle); 2100 lle = lle_tmp; 2101 lle_tmp = NULL; 2102 } 2103 } 2104 } 2105 if (lle == NULL) { 2106 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { 2107 m_freem(m); 2108 return (ENOBUFS); 2109 } 2110 2111 if (m != NULL) 2112 m_freem(m); 2113 return (ENOBUFS); 2114 } 2115 2116 LLE_WLOCK_ASSERT(lle); 2117 2118 /* 2119 * The first time we send a packet to a neighbor whose entry is 2120 * STALE, we have to change the state to DELAY and a sets a timer to 2121 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2122 * neighbor unreachability detection on expiration. 2123 * (RFC 2461 7.3.3) 2124 */ 2125 if (lle->ln_state == ND6_LLINFO_STALE) 2126 nd6_llinfo_setstate(lle, ND6_LLINFO_DELAY); 2127 2128 /* 2129 * If the neighbor cache entry has a state other than INCOMPLETE 2130 * (i.e. its link-layer address is already resolved), just 2131 * send the packet. 2132 */ 2133 if (lle->ln_state > ND6_LLINFO_INCOMPLETE) { 2134 bcopy(&lle->ll_addr, desten, ifp->if_addrlen); 2135 if (pflags != NULL) 2136 *pflags = lle->la_flags; 2137 LLE_WUNLOCK(lle); 2138 return (0); 2139 } 2140 2141 /* 2142 * There is a neighbor cache entry, but no ethernet address 2143 * response yet. Append this latest packet to the end of the 2144 * packet queue in the mbuf, unless the number of the packet 2145 * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, 2146 * the oldest packet in the queue will be removed. 2147 */ 2148 2149 if (lle->la_hold != NULL) { 2150 struct mbuf *m_hold; 2151 int i; 2152 2153 i = 0; 2154 for (m_hold = lle->la_hold; m_hold; m_hold = m_hold->m_nextpkt){ 2155 i++; 2156 if (m_hold->m_nextpkt == NULL) { 2157 m_hold->m_nextpkt = m; 2158 break; 2159 } 2160 } 2161 while (i >= V_nd6_maxqueuelen) { 2162 m_hold = lle->la_hold; 2163 lle->la_hold = lle->la_hold->m_nextpkt; 2164 m_freem(m_hold); 2165 i--; 2166 } 2167 } else { 2168 lle->la_hold = m; 2169 } 2170 2171 /* 2172 * If there has been no NS for the neighbor after entering the 2173 * INCOMPLETE state, send the first solicitation. 2174 * Note that for newly-created lle la_asked will be 0, 2175 * so we will transition from ND6_LLINFO_NOSTATE to 2176 * ND6_LLINFO_INCOMPLETE state here. 2177 */ 2178 psrc = NULL; 2179 send_ns = 0; 2180 if (lle->la_asked == 0) { 2181 lle->la_asked++; 2182 send_ns = 1; 2183 psrc = nd6_llinfo_get_holdsrc(lle, &src); 2184 2185 nd6_llinfo_setstate(lle, ND6_LLINFO_INCOMPLETE); 2186 } 2187 LLE_WUNLOCK(lle); 2188 if (send_ns != 0) 2189 nd6_ns_output(ifp, psrc, NULL, &dst->sin6_addr, NULL); 2190 2191 return (EWOULDBLOCK); 2192 } 2193 2194 2195 int 2196 nd6_flush_holdchain(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *chain, 2197 struct sockaddr_in6 *dst) 2198 { 2199 struct mbuf *m, *m_head; 2200 struct ifnet *outifp; 2201 int error = 0; 2202 2203 m_head = chain; 2204 if ((ifp->if_flags & IFF_LOOPBACK) != 0) 2205 outifp = origifp; 2206 else 2207 outifp = ifp; 2208 2209 while (m_head) { 2210 m = m_head; 2211 m_head = m_head->m_nextpkt; 2212 error = nd6_output_ifp(ifp, origifp, m, dst); 2213 } 2214 2215 /* 2216 * XXX 2217 * note that intermediate errors are blindly ignored 2218 */ 2219 return (error); 2220 } 2221 2222 static int 2223 nd6_need_cache(struct ifnet *ifp) 2224 { 2225 /* 2226 * XXX: we currently do not make neighbor cache on any interface 2227 * other than ARCnet, Ethernet, FDDI and GIF. 2228 * 2229 * RFC2893 says: 2230 * - unidirectional tunnels needs no ND 2231 */ 2232 switch (ifp->if_type) { 2233 case IFT_ARCNET: 2234 case IFT_ETHER: 2235 case IFT_FDDI: 2236 case IFT_IEEE1394: 2237 case IFT_L2VLAN: 2238 case IFT_IEEE80211: 2239 case IFT_INFINIBAND: 2240 case IFT_BRIDGE: 2241 case IFT_PROPVIRTUAL: 2242 return (1); 2243 default: 2244 return (0); 2245 } 2246 } 2247 2248 /* 2249 * Add pernament ND6 link-layer record for given 2250 * interface address. 2251 * 2252 * Very similar to IPv4 arp_ifinit(), but: 2253 * 1) IPv6 DAD is performed in different place 2254 * 2) It is called by IPv6 protocol stack in contrast to 2255 * arp_ifinit() which is typically called in SIOCSIFADDR 2256 * driver ioctl handler. 2257 * 2258 */ 2259 int 2260 nd6_add_ifa_lle(struct in6_ifaddr *ia) 2261 { 2262 struct ifnet *ifp; 2263 struct llentry *ln, *ln_tmp; 2264 struct sockaddr *dst; 2265 2266 ifp = ia->ia_ifa.ifa_ifp; 2267 if (nd6_need_cache(ifp) == 0) 2268 return (0); 2269 2270 ia->ia_ifa.ifa_rtrequest = nd6_rtrequest; 2271 dst = (struct sockaddr *)&ia->ia_addr; 2272 ln = lltable_alloc_entry(LLTABLE6(ifp), LLE_IFADDR, dst); 2273 if (ln == NULL) 2274 return (ENOBUFS); 2275 2276 IF_AFDATA_WLOCK(ifp); 2277 LLE_WLOCK(ln); 2278 /* Unlink any entry if exists */ 2279 ln_tmp = lla_lookup(LLTABLE6(ifp), LLE_EXCLUSIVE, dst); 2280 if (ln_tmp != NULL) 2281 lltable_unlink_entry(LLTABLE6(ifp), ln_tmp); 2282 lltable_link_entry(LLTABLE6(ifp), ln); 2283 IF_AFDATA_WUNLOCK(ifp); 2284 2285 if (ln_tmp != NULL) 2286 EVENTHANDLER_INVOKE(lle_event, ln_tmp, LLENTRY_EXPIRED); 2287 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 2288 2289 LLE_WUNLOCK(ln); 2290 if (ln_tmp != NULL) 2291 llentry_free(ln_tmp); 2292 2293 return (0); 2294 } 2295 2296 /* 2297 * Removes either all lle entries for given @ia, or lle 2298 * corresponding to @ia address. 2299 */ 2300 void 2301 nd6_rem_ifa_lle(struct in6_ifaddr *ia, int all) 2302 { 2303 struct sockaddr_in6 mask, addr; 2304 struct sockaddr *saddr, *smask; 2305 struct ifnet *ifp; 2306 2307 ifp = ia->ia_ifa.ifa_ifp; 2308 memcpy(&addr, &ia->ia_addr, sizeof(ia->ia_addr)); 2309 memcpy(&mask, &ia->ia_prefixmask, sizeof(ia->ia_prefixmask)); 2310 saddr = (struct sockaddr *)&addr; 2311 smask = (struct sockaddr *)&mask; 2312 2313 if (all != 0) 2314 lltable_prefix_free(AF_INET6, saddr, smask, LLE_STATIC); 2315 else 2316 lltable_delete_addr(LLTABLE6(ifp), LLE_IFADDR, saddr); 2317 } 2318 2319 static void 2320 clear_llinfo_pqueue(struct llentry *ln) 2321 { 2322 struct mbuf *m_hold, *m_hold_next; 2323 2324 for (m_hold = ln->la_hold; m_hold; m_hold = m_hold_next) { 2325 m_hold_next = m_hold->m_nextpkt; 2326 m_freem(m_hold); 2327 } 2328 2329 ln->la_hold = NULL; 2330 return; 2331 } 2332 2333 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS); 2334 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS); 2335 #ifdef SYSCTL_DECL 2336 SYSCTL_DECL(_net_inet6_icmp6); 2337 #endif 2338 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist, 2339 CTLFLAG_RD, nd6_sysctl_drlist, ""); 2340 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist, 2341 CTLFLAG_RD, nd6_sysctl_prlist, ""); 2342 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen, 2343 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, ""); 2344 SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, nd6_gctimer, 2345 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_gctimer), (60 * 60 * 24), ""); 2346 2347 static int 2348 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS) 2349 { 2350 struct in6_defrouter d; 2351 struct nd_defrouter *dr; 2352 int error; 2353 2354 if (req->newptr) 2355 return (EPERM); 2356 2357 bzero(&d, sizeof(d)); 2358 d.rtaddr.sin6_family = AF_INET6; 2359 d.rtaddr.sin6_len = sizeof(d.rtaddr); 2360 2361 /* 2362 * XXX locking 2363 */ 2364 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) { 2365 d.rtaddr.sin6_addr = dr->rtaddr; 2366 error = sa6_recoverscope(&d.rtaddr); 2367 if (error != 0) 2368 return (error); 2369 d.flags = dr->flags; 2370 d.rtlifetime = dr->rtlifetime; 2371 d.expire = dr->expire + (time_second - time_uptime); 2372 d.if_index = dr->ifp->if_index; 2373 error = SYSCTL_OUT(req, &d, sizeof(d)); 2374 if (error != 0) 2375 return (error); 2376 } 2377 return (0); 2378 } 2379 2380 static int 2381 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS) 2382 { 2383 struct in6_prefix p; 2384 struct sockaddr_in6 s6; 2385 struct nd_prefix *pr; 2386 struct nd_pfxrouter *pfr; 2387 time_t maxexpire; 2388 int error; 2389 char ip6buf[INET6_ADDRSTRLEN]; 2390 2391 if (req->newptr) 2392 return (EPERM); 2393 2394 bzero(&p, sizeof(p)); 2395 p.origin = PR_ORIG_RA; 2396 bzero(&s6, sizeof(s6)); 2397 s6.sin6_family = AF_INET6; 2398 s6.sin6_len = sizeof(s6); 2399 2400 /* 2401 * XXX locking 2402 */ 2403 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 2404 p.prefix = pr->ndpr_prefix; 2405 if (sa6_recoverscope(&p.prefix)) { 2406 log(LOG_ERR, "scope error in prefix list (%s)\n", 2407 ip6_sprintf(ip6buf, &p.prefix.sin6_addr)); 2408 /* XXX: press on... */ 2409 } 2410 p.raflags = pr->ndpr_raf; 2411 p.prefixlen = pr->ndpr_plen; 2412 p.vltime = pr->ndpr_vltime; 2413 p.pltime = pr->ndpr_pltime; 2414 p.if_index = pr->ndpr_ifp->if_index; 2415 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2416 p.expire = 0; 2417 else { 2418 /* XXX: we assume time_t is signed. */ 2419 maxexpire = (-1) & 2420 ~((time_t)1 << ((sizeof(maxexpire) * 8) - 1)); 2421 if (pr->ndpr_vltime < maxexpire - pr->ndpr_lastupdate) 2422 p.expire = pr->ndpr_lastupdate + 2423 pr->ndpr_vltime + 2424 (time_second - time_uptime); 2425 else 2426 p.expire = maxexpire; 2427 } 2428 p.refcnt = pr->ndpr_refcnt; 2429 p.flags = pr->ndpr_stateflags; 2430 p.advrtrs = 0; 2431 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) 2432 p.advrtrs++; 2433 error = SYSCTL_OUT(req, &p, sizeof(p)); 2434 if (error != 0) 2435 return (error); 2436 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) { 2437 s6.sin6_addr = pfr->router->rtaddr; 2438 if (sa6_recoverscope(&s6)) 2439 log(LOG_ERR, 2440 "scope error in prefix list (%s)\n", 2441 ip6_sprintf(ip6buf, &pfr->router->rtaddr)); 2442 error = SYSCTL_OUT(req, &s6, sizeof(s6)); 2443 if (error != 0) 2444 return (error); 2445 } 2446 } 2447 return (0); 2448 } 2449