1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $ 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_route.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/eventhandler.h> 44 #include <sys/callout.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/mutex.h> 49 #include <sys/socket.h> 50 #include <sys/sockio.h> 51 #include <sys/time.h> 52 #include <sys/kernel.h> 53 #include <sys/protosw.h> 54 #include <sys/errno.h> 55 #include <sys/syslog.h> 56 #include <sys/rwlock.h> 57 #include <sys/queue.h> 58 #include <sys/sdt.h> 59 #include <sys/sysctl.h> 60 61 #include <net/if.h> 62 #include <net/if_var.h> 63 #include <net/if_dl.h> 64 #include <net/if_types.h> 65 #include <net/route.h> 66 #include <net/route/route_ctl.h> 67 #include <net/route/nhop.h> 68 #include <net/vnet.h> 69 70 #include <netinet/in.h> 71 #include <netinet/in_kdtrace.h> 72 #include <net/if_llatbl.h> 73 #include <netinet/if_ether.h> 74 #include <netinet6/in6_var.h> 75 #include <netinet/ip6.h> 76 #include <netinet6/ip6_var.h> 77 #include <netinet6/scope6_var.h> 78 #include <netinet6/nd6.h> 79 #include <netinet6/in6_ifattach.h> 80 #include <netinet/icmp6.h> 81 #include <netinet6/send.h> 82 83 #include <sys/limits.h> 84 85 #include <security/mac/mac_framework.h> 86 87 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ 88 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ 89 90 #define SIN6(s) ((const struct sockaddr_in6 *)(s)) 91 92 MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery"); 93 94 /* timer values */ 95 VNET_DEFINE(int, nd6_prune) = 1; /* walk list every 1 seconds */ 96 VNET_DEFINE(int, nd6_delay) = 5; /* delay first probe time 5 second */ 97 VNET_DEFINE(int, nd6_umaxtries) = 3; /* maximum unicast query */ 98 VNET_DEFINE(int, nd6_mmaxtries) = 3; /* maximum multicast query */ 99 VNET_DEFINE(int, nd6_useloopback) = 1; /* use loopback interface for 100 * local traffic */ 101 VNET_DEFINE(int, nd6_gctimer) = (60 * 60 * 24); /* 1 day: garbage 102 * collection timer */ 103 104 /* preventing too many loops in ND option parsing */ 105 VNET_DEFINE_STATIC(int, nd6_maxndopt) = 10; /* max # of ND options allowed */ 106 107 VNET_DEFINE(int, nd6_maxnudhint) = 0; /* max # of subsequent upper 108 * layer hints */ 109 VNET_DEFINE_STATIC(int, nd6_maxqueuelen) = 16; /* max pkts cached in unresolved 110 * ND entries */ 111 #define V_nd6_maxndopt VNET(nd6_maxndopt) 112 #define V_nd6_maxqueuelen VNET(nd6_maxqueuelen) 113 114 #ifdef ND6_DEBUG 115 VNET_DEFINE(int, nd6_debug) = 1; 116 #else 117 VNET_DEFINE(int, nd6_debug) = 0; 118 #endif 119 120 static eventhandler_tag lle_event_eh, iflladdr_event_eh, ifnet_link_event_eh; 121 122 VNET_DEFINE(struct nd_prhead, nd_prefix); 123 VNET_DEFINE(struct rwlock, nd6_lock); 124 VNET_DEFINE(uint64_t, nd6_list_genid); 125 VNET_DEFINE(struct mtx, nd6_onlink_mtx); 126 127 VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL; 128 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) 129 130 int (*send_sendso_input_hook)(struct mbuf *, struct ifnet *, int, int); 131 132 static int nd6_is_new_addr_neighbor(const struct sockaddr_in6 *, 133 struct ifnet *); 134 static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *); 135 static void nd6_slowtimo(void *); 136 static int regen_tmpaddr(struct in6_ifaddr *); 137 static void nd6_free(struct llentry **, int); 138 static void nd6_free_redirect(const struct llentry *); 139 static void nd6_llinfo_timer(void *); 140 static void nd6_llinfo_settimer_locked(struct llentry *, long); 141 static void clear_llinfo_pqueue(struct llentry *); 142 static int nd6_resolve_slow(struct ifnet *, int, int, struct mbuf *, 143 const struct sockaddr_in6 *, u_char *, uint32_t *, struct llentry **); 144 static int nd6_need_cache(struct ifnet *); 145 146 VNET_DEFINE_STATIC(struct callout, nd6_slowtimo_ch); 147 #define V_nd6_slowtimo_ch VNET(nd6_slowtimo_ch) 148 149 VNET_DEFINE_STATIC(struct callout, nd6_timer_ch); 150 #define V_nd6_timer_ch VNET(nd6_timer_ch) 151 152 SYSCTL_DECL(_net_inet6_icmp6); 153 154 static void 155 nd6_lle_event(void *arg __unused, struct llentry *lle, int evt) 156 { 157 struct rt_addrinfo rtinfo; 158 struct sockaddr_in6 dst; 159 struct sockaddr_dl gw; 160 struct ifnet *ifp; 161 int type; 162 int fibnum; 163 164 LLE_WLOCK_ASSERT(lle); 165 166 if (lltable_get_af(lle->lle_tbl) != AF_INET6) 167 return; 168 169 switch (evt) { 170 case LLENTRY_RESOLVED: 171 type = RTM_ADD; 172 KASSERT(lle->la_flags & LLE_VALID, 173 ("%s: %p resolved but not valid?", __func__, lle)); 174 break; 175 case LLENTRY_EXPIRED: 176 type = RTM_DELETE; 177 break; 178 default: 179 return; 180 } 181 182 ifp = lltable_get_ifp(lle->lle_tbl); 183 184 bzero(&dst, sizeof(dst)); 185 bzero(&gw, sizeof(gw)); 186 bzero(&rtinfo, sizeof(rtinfo)); 187 lltable_fill_sa_entry(lle, (struct sockaddr *)&dst); 188 dst.sin6_scope_id = in6_getscopezone(ifp, 189 in6_addrscope(&dst.sin6_addr)); 190 gw.sdl_len = sizeof(struct sockaddr_dl); 191 gw.sdl_family = AF_LINK; 192 gw.sdl_alen = ifp->if_addrlen; 193 gw.sdl_index = ifp->if_index; 194 gw.sdl_type = ifp->if_type; 195 if (evt == LLENTRY_RESOLVED) 196 bcopy(lle->ll_addr, gw.sdl_data, ifp->if_addrlen); 197 rtinfo.rti_info[RTAX_DST] = (struct sockaddr *)&dst; 198 rtinfo.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&gw; 199 rtinfo.rti_addrs = RTA_DST | RTA_GATEWAY; 200 fibnum = V_rt_add_addr_allfibs ? RT_ALL_FIBS : ifp->if_fib; 201 rt_missmsg_fib(type, &rtinfo, RTF_HOST | RTF_LLDATA | ( 202 type == RTM_ADD ? RTF_UP: 0), 0, fibnum); 203 } 204 205 /* 206 * A handler for interface link layer address change event. 207 */ 208 static void 209 nd6_iflladdr(void *arg __unused, struct ifnet *ifp) 210 { 211 if (ifp->if_afdata[AF_INET6] == NULL) 212 return; 213 214 lltable_update_ifaddr(LLTABLE6(ifp)); 215 } 216 217 void 218 nd6_init(void) 219 { 220 221 mtx_init(&V_nd6_onlink_mtx, "nd6 onlink", NULL, MTX_DEF); 222 rw_init(&V_nd6_lock, "nd6 list"); 223 224 LIST_INIT(&V_nd_prefix); 225 nd6_defrouter_init(); 226 227 /* Start timers. */ 228 callout_init(&V_nd6_slowtimo_ch, 1); 229 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 230 nd6_slowtimo, curvnet); 231 232 callout_init(&V_nd6_timer_ch, 1); 233 callout_reset(&V_nd6_timer_ch, hz, nd6_timer, curvnet); 234 235 nd6_dad_init(); 236 if (IS_DEFAULT_VNET(curvnet)) { 237 lle_event_eh = EVENTHANDLER_REGISTER(lle_event, nd6_lle_event, 238 NULL, EVENTHANDLER_PRI_ANY); 239 iflladdr_event_eh = EVENTHANDLER_REGISTER(iflladdr_event, 240 nd6_iflladdr, NULL, EVENTHANDLER_PRI_ANY); 241 ifnet_link_event_eh = EVENTHANDLER_REGISTER(ifnet_link_event, 242 nd6_ifnet_link_event, NULL, EVENTHANDLER_PRI_ANY); 243 } 244 } 245 246 #ifdef VIMAGE 247 void 248 nd6_destroy() 249 { 250 251 callout_drain(&V_nd6_slowtimo_ch); 252 callout_drain(&V_nd6_timer_ch); 253 if (IS_DEFAULT_VNET(curvnet)) { 254 EVENTHANDLER_DEREGISTER(ifnet_link_event, ifnet_link_event_eh); 255 EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh); 256 EVENTHANDLER_DEREGISTER(iflladdr_event, iflladdr_event_eh); 257 } 258 rw_destroy(&V_nd6_lock); 259 mtx_destroy(&V_nd6_onlink_mtx); 260 } 261 #endif 262 263 struct nd_ifinfo * 264 nd6_ifattach(struct ifnet *ifp) 265 { 266 struct nd_ifinfo *nd; 267 268 nd = malloc(sizeof(*nd), M_IP6NDP, M_WAITOK | M_ZERO); 269 nd->initialized = 1; 270 271 nd->chlim = IPV6_DEFHLIM; 272 nd->basereachable = REACHABLE_TIME; 273 nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); 274 nd->retrans = RETRANS_TIMER; 275 276 nd->flags = ND6_IFF_PERFORMNUD; 277 278 /* Set IPv6 disabled on all interfaces but loopback by default. */ 279 if ((ifp->if_flags & IFF_LOOPBACK) == 0) 280 nd->flags |= ND6_IFF_IFDISABLED; 281 282 /* A loopback interface always has ND6_IFF_AUTO_LINKLOCAL. 283 * XXXHRS: Clear ND6_IFF_AUTO_LINKLOCAL on an IFT_BRIDGE interface by 284 * default regardless of the V_ip6_auto_linklocal configuration to 285 * give a reasonable default behavior. 286 */ 287 if ((V_ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) || 288 (ifp->if_flags & IFF_LOOPBACK)) 289 nd->flags |= ND6_IFF_AUTO_LINKLOCAL; 290 /* 291 * A loopback interface does not need to accept RTADV. 292 * XXXHRS: Clear ND6_IFF_ACCEPT_RTADV on an IFT_BRIDGE interface by 293 * default regardless of the V_ip6_accept_rtadv configuration to 294 * prevent the interface from accepting RA messages arrived 295 * on one of the member interfaces with ND6_IFF_ACCEPT_RTADV. 296 */ 297 if (V_ip6_accept_rtadv && 298 !(ifp->if_flags & IFF_LOOPBACK) && 299 (ifp->if_type != IFT_BRIDGE)) { 300 nd->flags |= ND6_IFF_ACCEPT_RTADV; 301 /* If we globally accept rtadv, assume IPv6 on. */ 302 nd->flags &= ~ND6_IFF_IFDISABLED; 303 } 304 if (V_ip6_no_radr && !(ifp->if_flags & IFF_LOOPBACK)) 305 nd->flags |= ND6_IFF_NO_RADR; 306 307 /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ 308 nd6_setmtu0(ifp, nd); 309 310 return nd; 311 } 312 313 void 314 nd6_ifdetach(struct ifnet *ifp, struct nd_ifinfo *nd) 315 { 316 struct epoch_tracker et; 317 struct ifaddr *ifa, *next; 318 319 NET_EPOCH_ENTER(et); 320 CK_STAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) { 321 if (ifa->ifa_addr->sa_family != AF_INET6) 322 continue; 323 324 /* stop DAD processing */ 325 nd6_dad_stop(ifa); 326 } 327 NET_EPOCH_EXIT(et); 328 329 free(nd, M_IP6NDP); 330 } 331 332 /* 333 * Reset ND level link MTU. This function is called when the physical MTU 334 * changes, which means we might have to adjust the ND level MTU. 335 */ 336 void 337 nd6_setmtu(struct ifnet *ifp) 338 { 339 if (ifp->if_afdata[AF_INET6] == NULL) 340 return; 341 342 nd6_setmtu0(ifp, ND_IFINFO(ifp)); 343 } 344 345 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */ 346 void 347 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi) 348 { 349 u_int32_t omaxmtu; 350 351 omaxmtu = ndi->maxmtu; 352 ndi->maxmtu = ifp->if_mtu; 353 354 /* 355 * Decreasing the interface MTU under IPV6 minimum MTU may cause 356 * undesirable situation. We thus notify the operator of the change 357 * explicitly. The check for omaxmtu is necessary to restrict the 358 * log to the case of changing the MTU, not initializing it. 359 */ 360 if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { 361 log(LOG_NOTICE, "nd6_setmtu0: " 362 "new link MTU on %s (%lu) is too small for IPv6\n", 363 if_name(ifp), (unsigned long)ndi->maxmtu); 364 } 365 366 if (ndi->maxmtu > V_in6_maxmtu) 367 in6_setmaxmtu(); /* check all interfaces just in case */ 368 369 } 370 371 void 372 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts) 373 { 374 375 bzero(ndopts, sizeof(*ndopts)); 376 ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; 377 ndopts->nd_opts_last 378 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); 379 380 if (icmp6len == 0) { 381 ndopts->nd_opts_done = 1; 382 ndopts->nd_opts_search = NULL; 383 } 384 } 385 386 /* 387 * Take one ND option. 388 */ 389 struct nd_opt_hdr * 390 nd6_option(union nd_opts *ndopts) 391 { 392 struct nd_opt_hdr *nd_opt; 393 int olen; 394 395 KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__)); 396 KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts", 397 __func__)); 398 if (ndopts->nd_opts_search == NULL) 399 return NULL; 400 if (ndopts->nd_opts_done) 401 return NULL; 402 403 nd_opt = ndopts->nd_opts_search; 404 405 /* make sure nd_opt_len is inside the buffer */ 406 if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { 407 bzero(ndopts, sizeof(*ndopts)); 408 return NULL; 409 } 410 411 olen = nd_opt->nd_opt_len << 3; 412 if (olen == 0) { 413 /* 414 * Message validation requires that all included 415 * options have a length that is greater than zero. 416 */ 417 bzero(ndopts, sizeof(*ndopts)); 418 return NULL; 419 } 420 421 ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); 422 if (ndopts->nd_opts_search > ndopts->nd_opts_last) { 423 /* option overruns the end of buffer, invalid */ 424 bzero(ndopts, sizeof(*ndopts)); 425 return NULL; 426 } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { 427 /* reached the end of options chain */ 428 ndopts->nd_opts_done = 1; 429 ndopts->nd_opts_search = NULL; 430 } 431 return nd_opt; 432 } 433 434 /* 435 * Parse multiple ND options. 436 * This function is much easier to use, for ND routines that do not need 437 * multiple options of the same type. 438 */ 439 int 440 nd6_options(union nd_opts *ndopts) 441 { 442 struct nd_opt_hdr *nd_opt; 443 int i = 0; 444 445 KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__)); 446 KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts", 447 __func__)); 448 if (ndopts->nd_opts_search == NULL) 449 return 0; 450 451 while (1) { 452 nd_opt = nd6_option(ndopts); 453 if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { 454 /* 455 * Message validation requires that all included 456 * options have a length that is greater than zero. 457 */ 458 ICMP6STAT_INC(icp6s_nd_badopt); 459 bzero(ndopts, sizeof(*ndopts)); 460 return -1; 461 } 462 463 if (nd_opt == NULL) 464 goto skip1; 465 466 switch (nd_opt->nd_opt_type) { 467 case ND_OPT_SOURCE_LINKADDR: 468 case ND_OPT_TARGET_LINKADDR: 469 case ND_OPT_MTU: 470 case ND_OPT_REDIRECTED_HEADER: 471 case ND_OPT_NONCE: 472 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 473 nd6log((LOG_INFO, 474 "duplicated ND6 option found (type=%d)\n", 475 nd_opt->nd_opt_type)); 476 /* XXX bark? */ 477 } else { 478 ndopts->nd_opt_array[nd_opt->nd_opt_type] 479 = nd_opt; 480 } 481 break; 482 case ND_OPT_PREFIX_INFORMATION: 483 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { 484 ndopts->nd_opt_array[nd_opt->nd_opt_type] 485 = nd_opt; 486 } 487 ndopts->nd_opts_pi_end = 488 (struct nd_opt_prefix_info *)nd_opt; 489 break; 490 /* What about ND_OPT_ROUTE_INFO? RFC 4191 */ 491 case ND_OPT_RDNSS: /* RFC 6106 */ 492 case ND_OPT_DNSSL: /* RFC 6106 */ 493 /* 494 * Silently ignore options we know and do not care about 495 * in the kernel. 496 */ 497 break; 498 default: 499 /* 500 * Unknown options must be silently ignored, 501 * to accommodate future extension to the protocol. 502 */ 503 nd6log((LOG_DEBUG, 504 "nd6_options: unsupported option %d - " 505 "option ignored\n", nd_opt->nd_opt_type)); 506 } 507 508 skip1: 509 i++; 510 if (i > V_nd6_maxndopt) { 511 ICMP6STAT_INC(icp6s_nd_toomanyopt); 512 nd6log((LOG_INFO, "too many loop in nd opt\n")); 513 break; 514 } 515 516 if (ndopts->nd_opts_done) 517 break; 518 } 519 520 return 0; 521 } 522 523 /* 524 * ND6 timer routine to handle ND6 entries 525 */ 526 static void 527 nd6_llinfo_settimer_locked(struct llentry *ln, long tick) 528 { 529 int canceled; 530 531 LLE_WLOCK_ASSERT(ln); 532 533 /* Do not schedule timers for child LLEs. */ 534 if (ln->la_flags & LLE_CHILD) 535 return; 536 537 if (tick < 0) { 538 ln->la_expire = 0; 539 ln->ln_ntick = 0; 540 canceled = callout_stop(&ln->lle_timer); 541 } else { 542 ln->la_expire = time_uptime + tick / hz; 543 LLE_ADDREF(ln); 544 if (tick > INT_MAX) { 545 ln->ln_ntick = tick - INT_MAX; 546 canceled = callout_reset(&ln->lle_timer, INT_MAX, 547 nd6_llinfo_timer, ln); 548 } else { 549 ln->ln_ntick = 0; 550 canceled = callout_reset(&ln->lle_timer, tick, 551 nd6_llinfo_timer, ln); 552 } 553 } 554 if (canceled > 0) 555 LLE_REMREF(ln); 556 } 557 558 /* 559 * Gets source address of the first packet in hold queue 560 * and stores it in @src. 561 * Returns pointer to @src (if hold queue is not empty) or NULL. 562 * 563 * Set noinline to be dtrace-friendly 564 */ 565 static __noinline struct in6_addr * 566 nd6_llinfo_get_holdsrc(struct llentry *ln, struct in6_addr *src) 567 { 568 struct ip6_hdr hdr; 569 struct mbuf *m; 570 571 if (ln->la_hold == NULL) 572 return (NULL); 573 574 /* 575 * assume every packet in la_hold has the same IP header 576 */ 577 m = ln->la_hold; 578 if (sizeof(hdr) > m->m_len) 579 return (NULL); 580 581 m_copydata(m, 0, sizeof(hdr), (caddr_t)&hdr); 582 *src = hdr.ip6_src; 583 584 return (src); 585 } 586 587 /* 588 * Checks if we need to switch from STALE state. 589 * 590 * RFC 4861 requires switching from STALE to DELAY state 591 * on first packet matching entry, waiting V_nd6_delay and 592 * transition to PROBE state (if upper layer confirmation was 593 * not received). 594 * 595 * This code performs a bit differently: 596 * On packet hit we don't change state (but desired state 597 * can be guessed by control plane). However, after V_nd6_delay 598 * seconds code will transition to PROBE state (so DELAY state 599 * is kinda skipped in most situations). 600 * 601 * Typically, V_nd6_gctimer is bigger than V_nd6_delay, so 602 * we perform the following upon entering STALE state: 603 * 604 * 1) Arm timer to run each V_nd6_delay seconds to make sure that 605 * if packet was transmitted at the start of given interval, we 606 * would be able to switch to PROBE state in V_nd6_delay seconds 607 * as user expects. 608 * 609 * 2) Reschedule timer until original V_nd6_gctimer expires keeping 610 * lle in STALE state (remaining timer value stored in lle_remtime). 611 * 612 * 3) Reschedule timer if packet was transmitted less that V_nd6_delay 613 * seconds ago. 614 * 615 * Returns non-zero value if the entry is still STALE (storing 616 * the next timer interval in @pdelay). 617 * 618 * Returns zero value if original timer expired or we need to switch to 619 * PROBE (store that in @do_switch variable). 620 */ 621 static int 622 nd6_is_stale(struct llentry *lle, long *pdelay, int *do_switch) 623 { 624 int nd_delay, nd_gctimer; 625 time_t lle_hittime; 626 long delay; 627 628 *do_switch = 0; 629 nd_gctimer = V_nd6_gctimer; 630 nd_delay = V_nd6_delay; 631 632 lle_hittime = llentry_get_hittime(lle); 633 634 if (lle_hittime == 0) { 635 /* 636 * Datapath feedback has been requested upon entering 637 * STALE state. No packets has been passed using this lle. 638 * Ask for the timer reschedule and keep STALE state. 639 */ 640 delay = (long)(MIN(nd_gctimer, nd_delay)); 641 delay *= hz; 642 if (lle->lle_remtime > delay) 643 lle->lle_remtime -= delay; 644 else { 645 delay = lle->lle_remtime; 646 lle->lle_remtime = 0; 647 } 648 649 if (delay == 0) { 650 /* 651 * The original ng6_gctime timeout ended, 652 * no more rescheduling. 653 */ 654 return (0); 655 } 656 657 *pdelay = delay; 658 return (1); 659 } 660 661 /* 662 * Packet received. Verify timestamp 663 */ 664 delay = (long)(time_uptime - lle_hittime); 665 if (delay < nd_delay) { 666 /* 667 * V_nd6_delay still not passed since the first 668 * hit in STALE state. 669 * Reschedule timer and return. 670 */ 671 *pdelay = (long)(nd_delay - delay) * hz; 672 return (1); 673 } 674 675 /* Request switching to probe */ 676 *do_switch = 1; 677 return (0); 678 } 679 680 /* 681 * Switch @lle state to new state optionally arming timers. 682 * 683 * Set noinline to be dtrace-friendly 684 */ 685 __noinline void 686 nd6_llinfo_setstate(struct llentry *lle, int newstate) 687 { 688 struct ifnet *ifp; 689 int nd_gctimer, nd_delay; 690 long delay, remtime; 691 692 delay = 0; 693 remtime = 0; 694 695 switch (newstate) { 696 case ND6_LLINFO_INCOMPLETE: 697 ifp = lle->lle_tbl->llt_ifp; 698 delay = (long)ND_IFINFO(ifp)->retrans * hz / 1000; 699 break; 700 case ND6_LLINFO_REACHABLE: 701 if (!ND6_LLINFO_PERMANENT(lle)) { 702 ifp = lle->lle_tbl->llt_ifp; 703 delay = (long)ND_IFINFO(ifp)->reachable * hz; 704 } 705 break; 706 case ND6_LLINFO_STALE: 707 708 llentry_request_feedback(lle); 709 nd_delay = V_nd6_delay; 710 nd_gctimer = V_nd6_gctimer; 711 712 delay = (long)(MIN(nd_gctimer, nd_delay)) * hz; 713 remtime = (long)nd_gctimer * hz - delay; 714 break; 715 case ND6_LLINFO_DELAY: 716 lle->la_asked = 0; 717 delay = (long)V_nd6_delay * hz; 718 break; 719 } 720 721 if (delay > 0) 722 nd6_llinfo_settimer_locked(lle, delay); 723 724 lle->lle_remtime = remtime; 725 lle->ln_state = newstate; 726 } 727 728 /* 729 * Timer-dependent part of nd state machine. 730 * 731 * Set noinline to be dtrace-friendly 732 */ 733 static __noinline void 734 nd6_llinfo_timer(void *arg) 735 { 736 struct epoch_tracker et; 737 struct llentry *ln; 738 struct in6_addr *dst, *pdst, *psrc, src; 739 struct ifnet *ifp; 740 struct nd_ifinfo *ndi; 741 int do_switch, send_ns; 742 long delay; 743 744 KASSERT(arg != NULL, ("%s: arg NULL", __func__)); 745 ln = (struct llentry *)arg; 746 ifp = lltable_get_ifp(ln->lle_tbl); 747 CURVNET_SET(ifp->if_vnet); 748 749 ND6_RLOCK(); 750 LLE_WLOCK(ln); 751 if (callout_pending(&ln->lle_timer)) { 752 /* 753 * Here we are a bit odd here in the treatment of 754 * active/pending. If the pending bit is set, it got 755 * rescheduled before I ran. The active 756 * bit we ignore, since if it was stopped 757 * in ll_tablefree() and was currently running 758 * it would have return 0 so the code would 759 * not have deleted it since the callout could 760 * not be stopped so we want to go through 761 * with the delete here now. If the callout 762 * was restarted, the pending bit will be back on and 763 * we just want to bail since the callout_reset would 764 * return 1 and our reference would have been removed 765 * by nd6_llinfo_settimer_locked above since canceled 766 * would have been 1. 767 */ 768 LLE_WUNLOCK(ln); 769 ND6_RUNLOCK(); 770 CURVNET_RESTORE(); 771 return; 772 } 773 NET_EPOCH_ENTER(et); 774 ndi = ND_IFINFO(ifp); 775 send_ns = 0; 776 dst = &ln->r_l3addr.addr6; 777 pdst = dst; 778 779 if (ln->ln_ntick > 0) { 780 if (ln->ln_ntick > INT_MAX) { 781 ln->ln_ntick -= INT_MAX; 782 nd6_llinfo_settimer_locked(ln, INT_MAX); 783 } else { 784 ln->ln_ntick = 0; 785 nd6_llinfo_settimer_locked(ln, ln->ln_ntick); 786 } 787 goto done; 788 } 789 790 if (ln->la_flags & LLE_STATIC) { 791 goto done; 792 } 793 794 if (ln->la_flags & LLE_DELETED) { 795 nd6_free(&ln, 0); 796 goto done; 797 } 798 799 switch (ln->ln_state) { 800 case ND6_LLINFO_INCOMPLETE: 801 if (ln->la_asked < V_nd6_mmaxtries) { 802 ln->la_asked++; 803 send_ns = 1; 804 /* Send NS to multicast address */ 805 pdst = NULL; 806 } else { 807 struct mbuf *m = ln->la_hold; 808 if (m) { 809 struct mbuf *m0; 810 811 /* 812 * assuming every packet in la_hold has the 813 * same IP header. Send error after unlock. 814 */ 815 m0 = m->m_nextpkt; 816 m->m_nextpkt = NULL; 817 ln->la_hold = m0; 818 clear_llinfo_pqueue(ln); 819 } 820 nd6_free(&ln, 0); 821 if (m != NULL) { 822 struct mbuf *n = m; 823 824 /* 825 * if there are any ummapped mbufs, we 826 * must free them, rather than using 827 * them for an ICMP, as they cannot be 828 * checksummed. 829 */ 830 while ((n = n->m_next) != NULL) { 831 if (n->m_flags & M_EXTPG) 832 break; 833 } 834 if (n != NULL) { 835 m_freem(m); 836 m = NULL; 837 } else { 838 icmp6_error2(m, ICMP6_DST_UNREACH, 839 ICMP6_DST_UNREACH_ADDR, 0, ifp); 840 } 841 } 842 } 843 break; 844 case ND6_LLINFO_REACHABLE: 845 if (!ND6_LLINFO_PERMANENT(ln)) 846 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); 847 break; 848 849 case ND6_LLINFO_STALE: 850 if (nd6_is_stale(ln, &delay, &do_switch) != 0) { 851 /* 852 * No packet has used this entry and GC timeout 853 * has not been passed. Reschedule timer and 854 * return. 855 */ 856 nd6_llinfo_settimer_locked(ln, delay); 857 break; 858 } 859 860 if (do_switch == 0) { 861 /* 862 * GC timer has ended and entry hasn't been used. 863 * Run Garbage collector (RFC 4861, 5.3) 864 */ 865 if (!ND6_LLINFO_PERMANENT(ln)) 866 nd6_free(&ln, 1); 867 break; 868 } 869 870 /* Entry has been used AND delay timer has ended. */ 871 872 /* FALLTHROUGH */ 873 874 case ND6_LLINFO_DELAY: 875 if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { 876 /* We need NUD */ 877 ln->la_asked = 1; 878 nd6_llinfo_setstate(ln, ND6_LLINFO_PROBE); 879 send_ns = 1; 880 } else 881 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); /* XXX */ 882 break; 883 case ND6_LLINFO_PROBE: 884 if (ln->la_asked < V_nd6_umaxtries) { 885 ln->la_asked++; 886 send_ns = 1; 887 } else { 888 nd6_free(&ln, 0); 889 } 890 break; 891 default: 892 panic("%s: paths in a dark night can be confusing: %d", 893 __func__, ln->ln_state); 894 } 895 done: 896 if (ln != NULL) 897 ND6_RUNLOCK(); 898 if (send_ns != 0) { 899 nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); 900 psrc = nd6_llinfo_get_holdsrc(ln, &src); 901 LLE_FREE_LOCKED(ln); 902 ln = NULL; 903 nd6_ns_output(ifp, psrc, pdst, dst, NULL); 904 } 905 906 if (ln != NULL) 907 LLE_FREE_LOCKED(ln); 908 NET_EPOCH_EXIT(et); 909 CURVNET_RESTORE(); 910 } 911 912 /* 913 * ND6 timer routine to expire default route list and prefix list 914 */ 915 void 916 nd6_timer(void *arg) 917 { 918 CURVNET_SET((struct vnet *) arg); 919 struct epoch_tracker et; 920 struct nd_prhead prl; 921 struct nd_prefix *pr, *npr; 922 struct ifnet *ifp; 923 struct in6_ifaddr *ia6, *nia6; 924 uint64_t genid; 925 926 LIST_INIT(&prl); 927 928 NET_EPOCH_ENTER(et); 929 nd6_defrouter_timer(); 930 931 /* 932 * expire interface addresses. 933 * in the past the loop was inside prefix expiry processing. 934 * However, from a stricter speci-confrmance standpoint, we should 935 * rather separate address lifetimes and prefix lifetimes. 936 * 937 * XXXRW: in6_ifaddrhead locking. 938 */ 939 addrloop: 940 CK_STAILQ_FOREACH_SAFE(ia6, &V_in6_ifaddrhead, ia_link, nia6) { 941 /* check address lifetime */ 942 if (IFA6_IS_INVALID(ia6)) { 943 int regen = 0; 944 945 /* 946 * If the expiring address is temporary, try 947 * regenerating a new one. This would be useful when 948 * we suspended a laptop PC, then turned it on after a 949 * period that could invalidate all temporary 950 * addresses. Although we may have to restart the 951 * loop (see below), it must be after purging the 952 * address. Otherwise, we'd see an infinite loop of 953 * regeneration. 954 */ 955 if (V_ip6_use_tempaddr && 956 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 957 if (regen_tmpaddr(ia6) == 0) 958 regen = 1; 959 } 960 961 in6_purgeaddr(&ia6->ia_ifa); 962 963 if (regen) 964 goto addrloop; /* XXX: see below */ 965 } else if (IFA6_IS_DEPRECATED(ia6)) { 966 int oldflags = ia6->ia6_flags; 967 968 ia6->ia6_flags |= IN6_IFF_DEPRECATED; 969 970 /* 971 * If a temporary address has just become deprecated, 972 * regenerate a new one if possible. 973 */ 974 if (V_ip6_use_tempaddr && 975 (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 976 (oldflags & IN6_IFF_DEPRECATED) == 0) { 977 if (regen_tmpaddr(ia6) == 0) { 978 /* 979 * A new temporary address is 980 * generated. 981 * XXX: this means the address chain 982 * has changed while we are still in 983 * the loop. Although the change 984 * would not cause disaster (because 985 * it's not a deletion, but an 986 * addition,) we'd rather restart the 987 * loop just for safety. Or does this 988 * significantly reduce performance?? 989 */ 990 goto addrloop; 991 } 992 } 993 } else if ((ia6->ia6_flags & IN6_IFF_TENTATIVE) != 0) { 994 /* 995 * Schedule DAD for a tentative address. This happens 996 * if the interface was down or not running 997 * when the address was configured. 998 */ 999 int delay; 1000 1001 delay = arc4random() % 1002 (MAX_RTR_SOLICITATION_DELAY * hz); 1003 nd6_dad_start((struct ifaddr *)ia6, delay); 1004 } else { 1005 /* 1006 * Check status of the interface. If it is down, 1007 * mark the address as tentative for future DAD. 1008 */ 1009 ifp = ia6->ia_ifp; 1010 if ((ND_IFINFO(ifp)->flags & ND6_IFF_NO_DAD) == 0 && 1011 ((ifp->if_flags & IFF_UP) == 0 || 1012 (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || 1013 (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0)){ 1014 ia6->ia6_flags &= ~IN6_IFF_DUPLICATED; 1015 ia6->ia6_flags |= IN6_IFF_TENTATIVE; 1016 } 1017 1018 /* 1019 * A new RA might have made a deprecated address 1020 * preferred. 1021 */ 1022 ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; 1023 } 1024 } 1025 NET_EPOCH_EXIT(et); 1026 1027 ND6_WLOCK(); 1028 restart: 1029 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) { 1030 /* 1031 * Expire prefixes. Since the pltime is only used for 1032 * autoconfigured addresses, pltime processing for prefixes is 1033 * not necessary. 1034 * 1035 * Only unlink after all derived addresses have expired. This 1036 * may not occur until two hours after the prefix has expired 1037 * per RFC 4862. If the prefix expires before its derived 1038 * addresses, mark it off-link. This will be done automatically 1039 * after unlinking if no address references remain. 1040 */ 1041 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME || 1042 time_uptime - pr->ndpr_lastupdate <= pr->ndpr_vltime) 1043 continue; 1044 1045 if (pr->ndpr_addrcnt == 0) { 1046 nd6_prefix_unlink(pr, &prl); 1047 continue; 1048 } 1049 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1050 genid = V_nd6_list_genid; 1051 nd6_prefix_ref(pr); 1052 ND6_WUNLOCK(); 1053 ND6_ONLINK_LOCK(); 1054 (void)nd6_prefix_offlink(pr); 1055 ND6_ONLINK_UNLOCK(); 1056 ND6_WLOCK(); 1057 nd6_prefix_rele(pr); 1058 if (genid != V_nd6_list_genid) 1059 goto restart; 1060 } 1061 } 1062 ND6_WUNLOCK(); 1063 1064 while ((pr = LIST_FIRST(&prl)) != NULL) { 1065 LIST_REMOVE(pr, ndpr_entry); 1066 nd6_prefix_del(pr); 1067 } 1068 1069 callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz, 1070 nd6_timer, curvnet); 1071 1072 CURVNET_RESTORE(); 1073 } 1074 1075 /* 1076 * ia6 - deprecated/invalidated temporary address 1077 */ 1078 static int 1079 regen_tmpaddr(struct in6_ifaddr *ia6) 1080 { 1081 struct ifaddr *ifa; 1082 struct ifnet *ifp; 1083 struct in6_ifaddr *public_ifa6 = NULL; 1084 1085 NET_EPOCH_ASSERT(); 1086 1087 ifp = ia6->ia_ifa.ifa_ifp; 1088 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1089 struct in6_ifaddr *it6; 1090 1091 if (ifa->ifa_addr->sa_family != AF_INET6) 1092 continue; 1093 1094 it6 = (struct in6_ifaddr *)ifa; 1095 1096 /* ignore no autoconf addresses. */ 1097 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1098 continue; 1099 1100 /* ignore autoconf addresses with different prefixes. */ 1101 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) 1102 continue; 1103 1104 /* 1105 * Now we are looking at an autoconf address with the same 1106 * prefix as ours. If the address is temporary and is still 1107 * preferred, do not create another one. It would be rare, but 1108 * could happen, for example, when we resume a laptop PC after 1109 * a long period. 1110 */ 1111 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1112 !IFA6_IS_DEPRECATED(it6)) { 1113 public_ifa6 = NULL; 1114 break; 1115 } 1116 1117 /* 1118 * This is a public autoconf address that has the same prefix 1119 * as ours. If it is preferred, keep it. We can't break the 1120 * loop here, because there may be a still-preferred temporary 1121 * address with the prefix. 1122 */ 1123 if (!IFA6_IS_DEPRECATED(it6)) 1124 public_ifa6 = it6; 1125 } 1126 if (public_ifa6 != NULL) 1127 ifa_ref(&public_ifa6->ia_ifa); 1128 1129 if (public_ifa6 != NULL) { 1130 int e; 1131 1132 if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { 1133 ifa_free(&public_ifa6->ia_ifa); 1134 log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" 1135 " tmp addr,errno=%d\n", e); 1136 return (-1); 1137 } 1138 ifa_free(&public_ifa6->ia_ifa); 1139 return (0); 1140 } 1141 1142 return (-1); 1143 } 1144 1145 /* 1146 * Remove prefix and default router list entries corresponding to ifp. Neighbor 1147 * cache entries are freed in in6_domifdetach(). 1148 */ 1149 void 1150 nd6_purge(struct ifnet *ifp) 1151 { 1152 struct nd_prhead prl; 1153 struct nd_prefix *pr, *npr; 1154 1155 LIST_INIT(&prl); 1156 1157 /* Purge default router list entries toward ifp. */ 1158 nd6_defrouter_purge(ifp); 1159 1160 ND6_WLOCK(); 1161 /* 1162 * Remove prefixes on ifp. We should have already removed addresses on 1163 * this interface, so no addresses should be referencing these prefixes. 1164 */ 1165 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) { 1166 if (pr->ndpr_ifp == ifp) 1167 nd6_prefix_unlink(pr, &prl); 1168 } 1169 ND6_WUNLOCK(); 1170 1171 /* Delete the unlinked prefix objects. */ 1172 while ((pr = LIST_FIRST(&prl)) != NULL) { 1173 LIST_REMOVE(pr, ndpr_entry); 1174 nd6_prefix_del(pr); 1175 } 1176 1177 /* cancel default outgoing interface setting */ 1178 if (V_nd6_defifindex == ifp->if_index) 1179 nd6_setdefaultiface(0); 1180 1181 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { 1182 /* Refresh default router list. */ 1183 defrouter_select_fib(ifp->if_fib); 1184 } 1185 } 1186 1187 /* 1188 * the caller acquires and releases the lock on the lltbls 1189 * Returns the llentry locked 1190 */ 1191 struct llentry * 1192 nd6_lookup(const struct in6_addr *addr6, int flags, struct ifnet *ifp) 1193 { 1194 struct sockaddr_in6 sin6; 1195 struct llentry *ln; 1196 1197 bzero(&sin6, sizeof(sin6)); 1198 sin6.sin6_len = sizeof(struct sockaddr_in6); 1199 sin6.sin6_family = AF_INET6; 1200 sin6.sin6_addr = *addr6; 1201 1202 IF_AFDATA_LOCK_ASSERT(ifp); 1203 1204 ln = lla_lookup(LLTABLE6(ifp), flags, (struct sockaddr *)&sin6); 1205 1206 return (ln); 1207 } 1208 1209 static struct llentry * 1210 nd6_alloc(const struct in6_addr *addr6, int flags, struct ifnet *ifp) 1211 { 1212 struct sockaddr_in6 sin6; 1213 struct llentry *ln; 1214 1215 bzero(&sin6, sizeof(sin6)); 1216 sin6.sin6_len = sizeof(struct sockaddr_in6); 1217 sin6.sin6_family = AF_INET6; 1218 sin6.sin6_addr = *addr6; 1219 1220 ln = lltable_alloc_entry(LLTABLE6(ifp), 0, (struct sockaddr *)&sin6); 1221 if (ln != NULL) 1222 ln->ln_state = ND6_LLINFO_NOSTATE; 1223 1224 return (ln); 1225 } 1226 1227 /* 1228 * Test whether a given IPv6 address is a neighbor or not, ignoring 1229 * the actual neighbor cache. The neighbor cache is ignored in order 1230 * to not reenter the routing code from within itself. 1231 */ 1232 static int 1233 nd6_is_new_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp) 1234 { 1235 struct nd_prefix *pr; 1236 struct ifaddr *ifa; 1237 struct rt_addrinfo info; 1238 struct sockaddr_in6 rt_key; 1239 const struct sockaddr *dst6; 1240 uint64_t genid; 1241 int error, fibnum; 1242 1243 /* 1244 * A link-local address is always a neighbor. 1245 * XXX: a link does not necessarily specify a single interface. 1246 */ 1247 if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { 1248 struct sockaddr_in6 sin6_copy; 1249 u_int32_t zone; 1250 1251 /* 1252 * We need sin6_copy since sa6_recoverscope() may modify the 1253 * content (XXX). 1254 */ 1255 sin6_copy = *addr; 1256 if (sa6_recoverscope(&sin6_copy)) 1257 return (0); /* XXX: should be impossible */ 1258 if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) 1259 return (0); 1260 if (sin6_copy.sin6_scope_id == zone) 1261 return (1); 1262 else 1263 return (0); 1264 } 1265 1266 bzero(&rt_key, sizeof(rt_key)); 1267 bzero(&info, sizeof(info)); 1268 info.rti_info[RTAX_DST] = (struct sockaddr *)&rt_key; 1269 1270 /* 1271 * If the address matches one of our addresses, 1272 * it should be a neighbor. 1273 * If the address matches one of our on-link prefixes, it should be a 1274 * neighbor. 1275 */ 1276 ND6_RLOCK(); 1277 restart: 1278 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1279 if (pr->ndpr_ifp != ifp) 1280 continue; 1281 1282 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1283 dst6 = (const struct sockaddr *)&pr->ndpr_prefix; 1284 1285 /* 1286 * We only need to check all FIBs if add_addr_allfibs 1287 * is unset. If set, checking any FIB will suffice. 1288 */ 1289 fibnum = V_rt_add_addr_allfibs ? rt_numfibs - 1 : 0; 1290 for (; fibnum < rt_numfibs; fibnum++) { 1291 genid = V_nd6_list_genid; 1292 ND6_RUNLOCK(); 1293 1294 /* 1295 * Restore length field before 1296 * retrying lookup 1297 */ 1298 rt_key.sin6_len = sizeof(rt_key); 1299 error = rib_lookup_info(fibnum, dst6, 0, 0, 1300 &info); 1301 1302 ND6_RLOCK(); 1303 if (genid != V_nd6_list_genid) 1304 goto restart; 1305 if (error == 0) 1306 break; 1307 } 1308 if (error != 0) 1309 continue; 1310 1311 /* 1312 * This is the case where multiple interfaces 1313 * have the same prefix, but only one is installed 1314 * into the routing table and that prefix entry 1315 * is not the one being examined here. 1316 */ 1317 if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 1318 &rt_key.sin6_addr)) 1319 continue; 1320 } 1321 1322 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, 1323 &addr->sin6_addr, &pr->ndpr_mask)) { 1324 ND6_RUNLOCK(); 1325 return (1); 1326 } 1327 } 1328 ND6_RUNLOCK(); 1329 1330 /* 1331 * If the address is assigned on the node of the other side of 1332 * a p2p interface, the address should be a neighbor. 1333 */ 1334 if (ifp->if_flags & IFF_POINTOPOINT) { 1335 struct epoch_tracker et; 1336 1337 NET_EPOCH_ENTER(et); 1338 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1339 if (ifa->ifa_addr->sa_family != addr->sin6_family) 1340 continue; 1341 if (ifa->ifa_dstaddr != NULL && 1342 sa_equal(addr, ifa->ifa_dstaddr)) { 1343 NET_EPOCH_EXIT(et); 1344 return 1; 1345 } 1346 } 1347 NET_EPOCH_EXIT(et); 1348 } 1349 1350 /* 1351 * If the default router list is empty, all addresses are regarded 1352 * as on-link, and thus, as a neighbor. 1353 */ 1354 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && 1355 nd6_defrouter_list_empty() && 1356 V_nd6_defifindex == ifp->if_index) { 1357 return (1); 1358 } 1359 1360 return (0); 1361 } 1362 1363 /* 1364 * Detect if a given IPv6 address identifies a neighbor on a given link. 1365 * XXX: should take care of the destination of a p2p link? 1366 */ 1367 int 1368 nd6_is_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp) 1369 { 1370 struct llentry *lle; 1371 int rc = 0; 1372 1373 NET_EPOCH_ASSERT(); 1374 IF_AFDATA_UNLOCK_ASSERT(ifp); 1375 if (nd6_is_new_addr_neighbor(addr, ifp)) 1376 return (1); 1377 1378 /* 1379 * Even if the address matches none of our addresses, it might be 1380 * in the neighbor cache. 1381 */ 1382 if ((lle = nd6_lookup(&addr->sin6_addr, LLE_SF(AF_INET6, 0), ifp)) != NULL) { 1383 LLE_RUNLOCK(lle); 1384 rc = 1; 1385 } 1386 return (rc); 1387 } 1388 1389 static __noinline void 1390 nd6_free_children(struct llentry *lle) 1391 { 1392 struct llentry *child_lle; 1393 1394 NET_EPOCH_ASSERT(); 1395 LLE_WLOCK_ASSERT(lle); 1396 1397 while ((child_lle = CK_SLIST_FIRST(&lle->lle_children)) != NULL) { 1398 LLE_WLOCK(child_lle); 1399 lltable_unlink_child_entry(child_lle); 1400 llentry_free(child_lle); 1401 } 1402 } 1403 1404 /* 1405 * Tries to update @lle address/prepend data with new @lladdr. 1406 * 1407 * Returns true on success. 1408 * In any case, @lle is returned wlocked. 1409 */ 1410 static __noinline bool 1411 nd6_try_set_entry_addr_locked(struct ifnet *ifp, struct llentry *lle, char *lladdr) 1412 { 1413 u_char buf[LLE_MAX_LINKHDR]; 1414 int fam, off; 1415 size_t sz; 1416 1417 sz = sizeof(buf); 1418 if (lltable_calc_llheader(ifp, AF_INET6, lladdr, buf, &sz, &off) != 0) 1419 return (false); 1420 1421 /* Update data */ 1422 lltable_set_entry_addr(ifp, lle, buf, sz, off); 1423 1424 struct llentry *child_lle; 1425 CK_SLIST_FOREACH(child_lle, &lle->lle_children, lle_child_next) { 1426 LLE_WLOCK(child_lle); 1427 fam = child_lle->r_family; 1428 sz = sizeof(buf); 1429 if (lltable_calc_llheader(ifp, fam, lladdr, buf, &sz, &off) == 0) { 1430 /* success */ 1431 lltable_set_entry_addr(ifp, child_lle, buf, sz, off); 1432 child_lle->ln_state = ND6_LLINFO_REACHABLE; 1433 } 1434 LLE_WUNLOCK(child_lle); 1435 } 1436 1437 return (true); 1438 } 1439 1440 bool 1441 nd6_try_set_entry_addr(struct ifnet *ifp, struct llentry *lle, char *lladdr) 1442 { 1443 NET_EPOCH_ASSERT(); 1444 LLE_WLOCK_ASSERT(lle); 1445 1446 if (!lltable_acquire_wlock(ifp, lle)) 1447 return (false); 1448 bool ret = nd6_try_set_entry_addr_locked(ifp, lle, lladdr); 1449 IF_AFDATA_WUNLOCK(ifp); 1450 1451 return (ret); 1452 } 1453 1454 /* 1455 * Free an nd6 llinfo entry. 1456 * Since the function would cause significant changes in the kernel, DO NOT 1457 * make it global, unless you have a strong reason for the change, and are sure 1458 * that the change is safe. 1459 * 1460 * Set noinline to be dtrace-friendly 1461 */ 1462 static __noinline void 1463 nd6_free(struct llentry **lnp, int gc) 1464 { 1465 struct ifnet *ifp; 1466 struct llentry *ln; 1467 struct nd_defrouter *dr; 1468 1469 ln = *lnp; 1470 *lnp = NULL; 1471 1472 LLE_WLOCK_ASSERT(ln); 1473 ND6_RLOCK_ASSERT(); 1474 1475 KASSERT((ln->la_flags & LLE_CHILD) == 0, ("child lle")); 1476 1477 ifp = lltable_get_ifp(ln->lle_tbl); 1478 if ((ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) != 0) 1479 dr = defrouter_lookup_locked(&ln->r_l3addr.addr6, ifp); 1480 else 1481 dr = NULL; 1482 ND6_RUNLOCK(); 1483 1484 if ((ln->la_flags & LLE_DELETED) == 0) 1485 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED); 1486 1487 /* 1488 * we used to have pfctlinput(PRC_HOSTDEAD) here. 1489 * even though it is not harmful, it was not really necessary. 1490 */ 1491 1492 /* cancel timer */ 1493 nd6_llinfo_settimer_locked(ln, -1); 1494 1495 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { 1496 if (dr != NULL && dr->expire && 1497 ln->ln_state == ND6_LLINFO_STALE && gc) { 1498 /* 1499 * If the reason for the deletion is just garbage 1500 * collection, and the neighbor is an active default 1501 * router, do not delete it. Instead, reset the GC 1502 * timer using the router's lifetime. 1503 * Simply deleting the entry would affect default 1504 * router selection, which is not necessarily a good 1505 * thing, especially when we're using router preference 1506 * values. 1507 * XXX: the check for ln_state would be redundant, 1508 * but we intentionally keep it just in case. 1509 */ 1510 if (dr->expire > time_uptime) 1511 nd6_llinfo_settimer_locked(ln, 1512 (dr->expire - time_uptime) * hz); 1513 else 1514 nd6_llinfo_settimer_locked(ln, 1515 (long)V_nd6_gctimer * hz); 1516 1517 LLE_REMREF(ln); 1518 LLE_WUNLOCK(ln); 1519 defrouter_rele(dr); 1520 return; 1521 } 1522 1523 if (dr) { 1524 /* 1525 * Unreachablity of a router might affect the default 1526 * router selection and on-link detection of advertised 1527 * prefixes. 1528 */ 1529 1530 /* 1531 * Temporarily fake the state to choose a new default 1532 * router and to perform on-link determination of 1533 * prefixes correctly. 1534 * Below the state will be set correctly, 1535 * or the entry itself will be deleted. 1536 */ 1537 ln->ln_state = ND6_LLINFO_INCOMPLETE; 1538 } 1539 1540 if (ln->ln_router || dr) { 1541 /* 1542 * We need to unlock to avoid a LOR with rt6_flush() with the 1543 * rnh and for the calls to pfxlist_onlink_check() and 1544 * defrouter_select_fib() in the block further down for calls 1545 * into nd6_lookup(). We still hold a ref. 1546 */ 1547 LLE_WUNLOCK(ln); 1548 1549 /* 1550 * rt6_flush must be called whether or not the neighbor 1551 * is in the Default Router List. 1552 * See a corresponding comment in nd6_na_input(). 1553 */ 1554 rt6_flush(&ln->r_l3addr.addr6, ifp); 1555 } 1556 1557 if (dr) { 1558 /* 1559 * Since defrouter_select_fib() does not affect the 1560 * on-link determination and MIP6 needs the check 1561 * before the default router selection, we perform 1562 * the check now. 1563 */ 1564 pfxlist_onlink_check(); 1565 1566 /* 1567 * Refresh default router list. 1568 */ 1569 defrouter_select_fib(dr->ifp->if_fib); 1570 } 1571 1572 /* 1573 * If this entry was added by an on-link redirect, remove the 1574 * corresponding host route. 1575 */ 1576 if (ln->la_flags & LLE_REDIRECT) 1577 nd6_free_redirect(ln); 1578 1579 if (ln->ln_router || dr) 1580 LLE_WLOCK(ln); 1581 } 1582 1583 /* 1584 * Save to unlock. We still hold an extra reference and will not 1585 * free(9) in llentry_free() if someone else holds one as well. 1586 */ 1587 LLE_WUNLOCK(ln); 1588 IF_AFDATA_LOCK(ifp); 1589 LLE_WLOCK(ln); 1590 /* Guard against race with other llentry_free(). */ 1591 if (ln->la_flags & LLE_LINKED) { 1592 /* Remove callout reference */ 1593 LLE_REMREF(ln); 1594 lltable_unlink_entry(ln->lle_tbl, ln); 1595 } 1596 IF_AFDATA_UNLOCK(ifp); 1597 1598 nd6_free_children(ln); 1599 1600 llentry_free(ln); 1601 if (dr != NULL) 1602 defrouter_rele(dr); 1603 } 1604 1605 static int 1606 nd6_isdynrte(const struct rtentry *rt, const struct nhop_object *nh, void *xap) 1607 { 1608 1609 if (nh->nh_flags & NHF_REDIRECT) 1610 return (1); 1611 1612 return (0); 1613 } 1614 1615 /* 1616 * Remove the rtentry for the given llentry, 1617 * both of which were installed by a redirect. 1618 */ 1619 static void 1620 nd6_free_redirect(const struct llentry *ln) 1621 { 1622 int fibnum; 1623 struct sockaddr_in6 sin6; 1624 struct rt_addrinfo info; 1625 struct rib_cmd_info rc; 1626 struct epoch_tracker et; 1627 1628 lltable_fill_sa_entry(ln, (struct sockaddr *)&sin6); 1629 memset(&info, 0, sizeof(info)); 1630 info.rti_info[RTAX_DST] = (struct sockaddr *)&sin6; 1631 info.rti_filter = nd6_isdynrte; 1632 1633 NET_EPOCH_ENTER(et); 1634 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) 1635 rib_action(fibnum, RTM_DELETE, &info, &rc); 1636 NET_EPOCH_EXIT(et); 1637 } 1638 1639 /* 1640 * Updates status of the default router route. 1641 */ 1642 static void 1643 check_release_defrouter(struct rib_cmd_info *rc, void *_cbdata) 1644 { 1645 struct nd_defrouter *dr; 1646 struct nhop_object *nh; 1647 1648 nh = rc->rc_nh_old; 1649 1650 if ((nh != NULL) && (nh->nh_flags & NHF_DEFAULT)) { 1651 dr = defrouter_lookup(&nh->gw6_sa.sin6_addr, nh->nh_ifp); 1652 if (dr != NULL) { 1653 dr->installed = 0; 1654 defrouter_rele(dr); 1655 } 1656 } 1657 } 1658 1659 void 1660 nd6_subscription_cb(struct rib_head *rnh, struct rib_cmd_info *rc, void *arg) 1661 { 1662 1663 #ifdef ROUTE_MPATH 1664 rib_decompose_notification(rc, check_release_defrouter, NULL); 1665 #else 1666 check_release_defrouter(rc, NULL); 1667 #endif 1668 } 1669 1670 int 1671 nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) 1672 { 1673 struct in6_ndireq *ndi = (struct in6_ndireq *)data; 1674 struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; 1675 struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; 1676 struct epoch_tracker et; 1677 int error = 0; 1678 1679 if (ifp->if_afdata[AF_INET6] == NULL) 1680 return (EPFNOSUPPORT); 1681 switch (cmd) { 1682 case OSIOCGIFINFO_IN6: 1683 #define ND ndi->ndi 1684 /* XXX: old ndp(8) assumes a positive value for linkmtu. */ 1685 bzero(&ND, sizeof(ND)); 1686 ND.linkmtu = IN6_LINKMTU(ifp); 1687 ND.maxmtu = ND_IFINFO(ifp)->maxmtu; 1688 ND.basereachable = ND_IFINFO(ifp)->basereachable; 1689 ND.reachable = ND_IFINFO(ifp)->reachable; 1690 ND.retrans = ND_IFINFO(ifp)->retrans; 1691 ND.flags = ND_IFINFO(ifp)->flags; 1692 ND.recalctm = ND_IFINFO(ifp)->recalctm; 1693 ND.chlim = ND_IFINFO(ifp)->chlim; 1694 break; 1695 case SIOCGIFINFO_IN6: 1696 ND = *ND_IFINFO(ifp); 1697 break; 1698 case SIOCSIFINFO_IN6: 1699 /* 1700 * used to change host variables from userland. 1701 * intended for a use on router to reflect RA configurations. 1702 */ 1703 /* 0 means 'unspecified' */ 1704 if (ND.linkmtu != 0) { 1705 if (ND.linkmtu < IPV6_MMTU || 1706 ND.linkmtu > IN6_LINKMTU(ifp)) { 1707 error = EINVAL; 1708 break; 1709 } 1710 ND_IFINFO(ifp)->linkmtu = ND.linkmtu; 1711 } 1712 1713 if (ND.basereachable != 0) { 1714 int obasereachable = ND_IFINFO(ifp)->basereachable; 1715 1716 ND_IFINFO(ifp)->basereachable = ND.basereachable; 1717 if (ND.basereachable != obasereachable) 1718 ND_IFINFO(ifp)->reachable = 1719 ND_COMPUTE_RTIME(ND.basereachable); 1720 } 1721 if (ND.retrans != 0) 1722 ND_IFINFO(ifp)->retrans = ND.retrans; 1723 if (ND.chlim != 0) 1724 ND_IFINFO(ifp)->chlim = ND.chlim; 1725 /* FALLTHROUGH */ 1726 case SIOCSIFINFO_FLAGS: 1727 { 1728 struct ifaddr *ifa; 1729 struct in6_ifaddr *ia; 1730 1731 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && 1732 !(ND.flags & ND6_IFF_IFDISABLED)) { 1733 /* ifdisabled 1->0 transision */ 1734 1735 /* 1736 * If the interface is marked as ND6_IFF_IFDISABLED and 1737 * has an link-local address with IN6_IFF_DUPLICATED, 1738 * do not clear ND6_IFF_IFDISABLED. 1739 * See RFC 4862, Section 5.4.5. 1740 */ 1741 NET_EPOCH_ENTER(et); 1742 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1743 if (ifa->ifa_addr->sa_family != AF_INET6) 1744 continue; 1745 ia = (struct in6_ifaddr *)ifa; 1746 if ((ia->ia6_flags & IN6_IFF_DUPLICATED) && 1747 IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) 1748 break; 1749 } 1750 NET_EPOCH_EXIT(et); 1751 1752 if (ifa != NULL) { 1753 /* LLA is duplicated. */ 1754 ND.flags |= ND6_IFF_IFDISABLED; 1755 log(LOG_ERR, "Cannot enable an interface" 1756 " with a link-local address marked" 1757 " duplicate.\n"); 1758 } else { 1759 ND_IFINFO(ifp)->flags &= ~ND6_IFF_IFDISABLED; 1760 if (ifp->if_flags & IFF_UP) 1761 in6_if_up(ifp); 1762 } 1763 } else if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && 1764 (ND.flags & ND6_IFF_IFDISABLED)) { 1765 /* ifdisabled 0->1 transision */ 1766 /* Mark all IPv6 address as tentative. */ 1767 1768 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1769 if (V_ip6_dad_count > 0 && 1770 (ND_IFINFO(ifp)->flags & ND6_IFF_NO_DAD) == 0) { 1771 NET_EPOCH_ENTER(et); 1772 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, 1773 ifa_link) { 1774 if (ifa->ifa_addr->sa_family != 1775 AF_INET6) 1776 continue; 1777 ia = (struct in6_ifaddr *)ifa; 1778 ia->ia6_flags |= IN6_IFF_TENTATIVE; 1779 } 1780 NET_EPOCH_EXIT(et); 1781 } 1782 } 1783 1784 if (ND.flags & ND6_IFF_AUTO_LINKLOCAL) { 1785 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL)) { 1786 /* auto_linklocal 0->1 transision */ 1787 1788 /* If no link-local address on ifp, configure */ 1789 ND_IFINFO(ifp)->flags |= ND6_IFF_AUTO_LINKLOCAL; 1790 in6_ifattach(ifp, NULL); 1791 } else if (!(ND.flags & ND6_IFF_IFDISABLED) && 1792 ifp->if_flags & IFF_UP) { 1793 /* 1794 * When the IF already has 1795 * ND6_IFF_AUTO_LINKLOCAL, no link-local 1796 * address is assigned, and IFF_UP, try to 1797 * assign one. 1798 */ 1799 NET_EPOCH_ENTER(et); 1800 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, 1801 ifa_link) { 1802 if (ifa->ifa_addr->sa_family != 1803 AF_INET6) 1804 continue; 1805 ia = (struct in6_ifaddr *)ifa; 1806 if (IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) 1807 break; 1808 } 1809 NET_EPOCH_EXIT(et); 1810 if (ifa != NULL) 1811 /* No LLA is configured. */ 1812 in6_ifattach(ifp, NULL); 1813 } 1814 } 1815 ND_IFINFO(ifp)->flags = ND.flags; 1816 break; 1817 } 1818 #undef ND 1819 case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ 1820 /* sync kernel routing table with the default router list */ 1821 defrouter_reset(); 1822 defrouter_select_fib(RT_ALL_FIBS); 1823 break; 1824 case SIOCSPFXFLUSH_IN6: 1825 { 1826 /* flush all the prefix advertised by routers */ 1827 struct in6_ifaddr *ia, *ia_next; 1828 struct nd_prefix *pr, *next; 1829 struct nd_prhead prl; 1830 1831 LIST_INIT(&prl); 1832 1833 ND6_WLOCK(); 1834 LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) { 1835 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1836 continue; /* XXX */ 1837 nd6_prefix_unlink(pr, &prl); 1838 } 1839 ND6_WUNLOCK(); 1840 1841 while ((pr = LIST_FIRST(&prl)) != NULL) { 1842 LIST_REMOVE(pr, ndpr_entry); 1843 /* XXXRW: in6_ifaddrhead locking. */ 1844 CK_STAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link, 1845 ia_next) { 1846 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1847 continue; 1848 1849 if (ia->ia6_ndpr == pr) 1850 in6_purgeaddr(&ia->ia_ifa); 1851 } 1852 nd6_prefix_del(pr); 1853 } 1854 break; 1855 } 1856 case SIOCSRTRFLUSH_IN6: 1857 { 1858 /* flush all the default routers */ 1859 1860 defrouter_reset(); 1861 nd6_defrouter_flush_all(); 1862 defrouter_select_fib(RT_ALL_FIBS); 1863 break; 1864 } 1865 case SIOCGNBRINFO_IN6: 1866 { 1867 struct llentry *ln; 1868 struct in6_addr nb_addr = nbi->addr; /* make local for safety */ 1869 1870 if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) 1871 return (error); 1872 1873 NET_EPOCH_ENTER(et); 1874 ln = nd6_lookup(&nb_addr, LLE_SF(AF_INET6, 0), ifp); 1875 NET_EPOCH_EXIT(et); 1876 1877 if (ln == NULL) { 1878 error = EINVAL; 1879 break; 1880 } 1881 nbi->state = ln->ln_state; 1882 nbi->asked = ln->la_asked; 1883 nbi->isrouter = ln->ln_router; 1884 if (ln->la_expire == 0) 1885 nbi->expire = 0; 1886 else 1887 nbi->expire = ln->la_expire + ln->lle_remtime / hz + 1888 (time_second - time_uptime); 1889 LLE_RUNLOCK(ln); 1890 break; 1891 } 1892 case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1893 ndif->ifindex = V_nd6_defifindex; 1894 break; 1895 case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ 1896 return (nd6_setdefaultiface(ndif->ifindex)); 1897 } 1898 return (error); 1899 } 1900 1901 /* 1902 * Calculates new isRouter value based on provided parameters and 1903 * returns it. 1904 */ 1905 static int 1906 nd6_is_router(int type, int code, int is_new, int old_addr, int new_addr, 1907 int ln_router) 1908 { 1909 1910 /* 1911 * ICMP6 type dependent behavior. 1912 * 1913 * NS: clear IsRouter if new entry 1914 * RS: clear IsRouter 1915 * RA: set IsRouter if there's lladdr 1916 * redir: clear IsRouter if new entry 1917 * 1918 * RA case, (1): 1919 * The spec says that we must set IsRouter in the following cases: 1920 * - If lladdr exist, set IsRouter. This means (1-5). 1921 * - If it is old entry (!newentry), set IsRouter. This means (7). 1922 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. 1923 * A quetion arises for (1) case. (1) case has no lladdr in the 1924 * neighbor cache, this is similar to (6). 1925 * This case is rare but we figured that we MUST NOT set IsRouter. 1926 * 1927 * is_new old_addr new_addr NS RS RA redir 1928 * D R 1929 * 0 n n (1) c ? s 1930 * 0 y n (2) c s s 1931 * 0 n y (3) c s s 1932 * 0 y y (4) c s s 1933 * 0 y y (5) c s s 1934 * 1 -- n (6) c c c s 1935 * 1 -- y (7) c c s c s 1936 * 1937 * (c=clear s=set) 1938 */ 1939 switch (type & 0xff) { 1940 case ND_NEIGHBOR_SOLICIT: 1941 /* 1942 * New entry must have is_router flag cleared. 1943 */ 1944 if (is_new) /* (6-7) */ 1945 ln_router = 0; 1946 break; 1947 case ND_REDIRECT: 1948 /* 1949 * If the icmp is a redirect to a better router, always set the 1950 * is_router flag. Otherwise, if the entry is newly created, 1951 * clear the flag. [RFC 2461, sec 8.3] 1952 */ 1953 if (code == ND_REDIRECT_ROUTER) 1954 ln_router = 1; 1955 else { 1956 if (is_new) /* (6-7) */ 1957 ln_router = 0; 1958 } 1959 break; 1960 case ND_ROUTER_SOLICIT: 1961 /* 1962 * is_router flag must always be cleared. 1963 */ 1964 ln_router = 0; 1965 break; 1966 case ND_ROUTER_ADVERT: 1967 /* 1968 * Mark an entry with lladdr as a router. 1969 */ 1970 if ((!is_new && (old_addr || new_addr)) || /* (2-5) */ 1971 (is_new && new_addr)) { /* (7) */ 1972 ln_router = 1; 1973 } 1974 break; 1975 } 1976 1977 return (ln_router); 1978 } 1979 1980 /* 1981 * Create neighbor cache entry and cache link-layer address, 1982 * on reception of inbound ND6 packets. (RS/RA/NS/redirect) 1983 * 1984 * type - ICMP6 type 1985 * code - type dependent information 1986 * 1987 */ 1988 void 1989 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr, 1990 int lladdrlen, int type, int code) 1991 { 1992 struct llentry *ln = NULL, *ln_tmp; 1993 int is_newentry; 1994 int do_update; 1995 int olladdr; 1996 int llchange; 1997 int flags; 1998 uint16_t router = 0; 1999 struct mbuf *chain = NULL; 2000 u_char linkhdr[LLE_MAX_LINKHDR]; 2001 size_t linkhdrsize; 2002 int lladdr_off; 2003 2004 NET_EPOCH_ASSERT(); 2005 IF_AFDATA_UNLOCK_ASSERT(ifp); 2006 2007 KASSERT(ifp != NULL, ("%s: ifp == NULL", __func__)); 2008 KASSERT(from != NULL, ("%s: from == NULL", __func__)); 2009 2010 /* nothing must be updated for unspecified address */ 2011 if (IN6_IS_ADDR_UNSPECIFIED(from)) 2012 return; 2013 2014 /* 2015 * Validation about ifp->if_addrlen and lladdrlen must be done in 2016 * the caller. 2017 * 2018 * XXX If the link does not have link-layer adderss, what should 2019 * we do? (ifp->if_addrlen == 0) 2020 * Spec says nothing in sections for RA, RS and NA. There's small 2021 * description on it in NS section (RFC 2461 7.2.3). 2022 */ 2023 flags = lladdr ? LLE_EXCLUSIVE : 0; 2024 ln = nd6_lookup(from, LLE_SF(AF_INET6, flags), ifp); 2025 is_newentry = 0; 2026 if (ln == NULL) { 2027 flags |= LLE_EXCLUSIVE; 2028 ln = nd6_alloc(from, 0, ifp); 2029 if (ln == NULL) 2030 return; 2031 2032 /* 2033 * Since we already know all the data for the new entry, 2034 * fill it before insertion. 2035 */ 2036 if (lladdr != NULL) { 2037 linkhdrsize = sizeof(linkhdr); 2038 if (lltable_calc_llheader(ifp, AF_INET6, lladdr, 2039 linkhdr, &linkhdrsize, &lladdr_off) != 0) { 2040 lltable_free_entry(LLTABLE6(ifp), ln); 2041 return; 2042 } 2043 lltable_set_entry_addr(ifp, ln, linkhdr, linkhdrsize, 2044 lladdr_off); 2045 } 2046 2047 IF_AFDATA_WLOCK(ifp); 2048 LLE_WLOCK(ln); 2049 /* Prefer any existing lle over newly-created one */ 2050 ln_tmp = nd6_lookup(from, LLE_SF(AF_INET6, LLE_EXCLUSIVE), ifp); 2051 if (ln_tmp == NULL) 2052 lltable_link_entry(LLTABLE6(ifp), ln); 2053 IF_AFDATA_WUNLOCK(ifp); 2054 if (ln_tmp == NULL) { 2055 /* No existing lle, mark as new entry (6,7) */ 2056 is_newentry = 1; 2057 if (lladdr != NULL) { /* (7) */ 2058 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); 2059 EVENTHANDLER_INVOKE(lle_event, ln, 2060 LLENTRY_RESOLVED); 2061 } 2062 } else { 2063 lltable_free_entry(LLTABLE6(ifp), ln); 2064 ln = ln_tmp; 2065 ln_tmp = NULL; 2066 } 2067 } 2068 /* do nothing if static ndp is set */ 2069 if ((ln->la_flags & LLE_STATIC)) { 2070 if (flags & LLE_EXCLUSIVE) 2071 LLE_WUNLOCK(ln); 2072 else 2073 LLE_RUNLOCK(ln); 2074 return; 2075 } 2076 2077 olladdr = (ln->la_flags & LLE_VALID) ? 1 : 0; 2078 if (olladdr && lladdr) { 2079 llchange = bcmp(lladdr, ln->ll_addr, 2080 ifp->if_addrlen); 2081 } else if (!olladdr && lladdr) 2082 llchange = 1; 2083 else 2084 llchange = 0; 2085 2086 /* 2087 * newentry olladdr lladdr llchange (*=record) 2088 * 0 n n -- (1) 2089 * 0 y n -- (2) 2090 * 0 n y y (3) * STALE 2091 * 0 y y n (4) * 2092 * 0 y y y (5) * STALE 2093 * 1 -- n -- (6) NOSTATE(= PASSIVE) 2094 * 1 -- y -- (7) * STALE 2095 */ 2096 2097 do_update = 0; 2098 if (is_newentry == 0 && llchange != 0) { 2099 do_update = 1; /* (3,5) */ 2100 2101 /* 2102 * Record source link-layer address 2103 * XXX is it dependent to ifp->if_type? 2104 */ 2105 if (!nd6_try_set_entry_addr(ifp, ln, lladdr)) { 2106 /* Entry was deleted */ 2107 LLE_WUNLOCK(ln); 2108 return; 2109 } 2110 2111 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); 2112 2113 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 2114 2115 if (ln->la_hold != NULL) 2116 chain = nd6_grab_holdchain(ln); 2117 } 2118 2119 /* Calculates new router status */ 2120 router = nd6_is_router(type, code, is_newentry, olladdr, 2121 lladdr != NULL ? 1 : 0, ln->ln_router); 2122 2123 ln->ln_router = router; 2124 /* Mark non-router redirects with special flag */ 2125 if ((type & 0xFF) == ND_REDIRECT && code != ND_REDIRECT_ROUTER) 2126 ln->la_flags |= LLE_REDIRECT; 2127 2128 if (flags & LLE_EXCLUSIVE) 2129 LLE_WUNLOCK(ln); 2130 else 2131 LLE_RUNLOCK(ln); 2132 2133 if (chain != NULL) 2134 nd6_flush_holdchain(ifp, ln, chain); 2135 if (do_update) 2136 nd6_flush_children_holdchain(ifp, ln); 2137 2138 /* 2139 * When the link-layer address of a router changes, select the 2140 * best router again. In particular, when the neighbor entry is newly 2141 * created, it might affect the selection policy. 2142 * Question: can we restrict the first condition to the "is_newentry" 2143 * case? 2144 * XXX: when we hear an RA from a new router with the link-layer 2145 * address option, defrouter_select_fib() is called twice, since 2146 * defrtrlist_update called the function as well. However, I believe 2147 * we can compromise the overhead, since it only happens the first 2148 * time. 2149 * XXX: although defrouter_select_fib() should not have a bad effect 2150 * for those are not autoconfigured hosts, we explicitly avoid such 2151 * cases for safety. 2152 */ 2153 if ((do_update || is_newentry) && router && 2154 ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { 2155 /* 2156 * guaranteed recursion 2157 */ 2158 defrouter_select_fib(ifp->if_fib); 2159 } 2160 } 2161 2162 static void 2163 nd6_slowtimo(void *arg) 2164 { 2165 struct epoch_tracker et; 2166 CURVNET_SET((struct vnet *) arg); 2167 struct nd_ifinfo *nd6if; 2168 struct ifnet *ifp; 2169 2170 callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, 2171 nd6_slowtimo, curvnet); 2172 NET_EPOCH_ENTER(et); 2173 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) { 2174 if (ifp->if_afdata[AF_INET6] == NULL) 2175 continue; 2176 nd6if = ND_IFINFO(ifp); 2177 if (nd6if->basereachable && /* already initialized */ 2178 (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { 2179 /* 2180 * Since reachable time rarely changes by router 2181 * advertisements, we SHOULD insure that a new random 2182 * value gets recomputed at least once every few hours. 2183 * (RFC 2461, 6.3.4) 2184 */ 2185 nd6if->recalctm = V_nd6_recalc_reachtm_interval; 2186 nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); 2187 } 2188 } 2189 NET_EPOCH_EXIT(et); 2190 CURVNET_RESTORE(); 2191 } 2192 2193 struct mbuf * 2194 nd6_grab_holdchain(struct llentry *ln) 2195 { 2196 struct mbuf *chain; 2197 2198 LLE_WLOCK_ASSERT(ln); 2199 2200 chain = ln->la_hold; 2201 ln->la_hold = NULL; 2202 2203 if (ln->ln_state == ND6_LLINFO_STALE) { 2204 /* 2205 * The first time we send a packet to a 2206 * neighbor whose entry is STALE, we have 2207 * to change the state to DELAY and a sets 2208 * a timer to expire in DELAY_FIRST_PROBE_TIME 2209 * seconds to ensure do neighbor unreachability 2210 * detection on expiration. 2211 * (RFC 2461 7.3.3) 2212 */ 2213 nd6_llinfo_setstate(ln, ND6_LLINFO_DELAY); 2214 } 2215 2216 return (chain); 2217 } 2218 2219 int 2220 nd6_output_ifp(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m, 2221 struct sockaddr_in6 *dst, struct route *ro) 2222 { 2223 int error; 2224 int ip6len; 2225 struct ip6_hdr *ip6; 2226 struct m_tag *mtag; 2227 2228 #ifdef MAC 2229 mac_netinet6_nd6_send(ifp, m); 2230 #endif 2231 2232 /* 2233 * If called from nd6_ns_output() (NS), nd6_na_output() (NA), 2234 * icmp6_redirect_output() (REDIRECT) or from rip6_output() (RS, RA 2235 * as handled by rtsol and rtadvd), mbufs will be tagged for SeND 2236 * to be diverted to user space. When re-injected into the kernel, 2237 * send_output() will directly dispatch them to the outgoing interface. 2238 */ 2239 if (send_sendso_input_hook != NULL) { 2240 mtag = m_tag_find(m, PACKET_TAG_ND_OUTGOING, NULL); 2241 if (mtag != NULL) { 2242 ip6 = mtod(m, struct ip6_hdr *); 2243 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen); 2244 /* Use the SEND socket */ 2245 error = send_sendso_input_hook(m, ifp, SND_OUT, 2246 ip6len); 2247 /* -1 == no app on SEND socket */ 2248 if (error == 0 || error != -1) 2249 return (error); 2250 } 2251 } 2252 2253 m_clrprotoflags(m); /* Avoid confusing lower layers. */ 2254 IP_PROBE(send, NULL, NULL, mtod(m, struct ip6_hdr *), ifp, NULL, 2255 mtod(m, struct ip6_hdr *)); 2256 2257 if ((ifp->if_flags & IFF_LOOPBACK) == 0) 2258 origifp = ifp; 2259 2260 error = (*ifp->if_output)(origifp, m, (struct sockaddr *)dst, ro); 2261 return (error); 2262 } 2263 2264 /* 2265 * Lookup link headerfor @sa_dst address. Stores found 2266 * data in @desten buffer. Copy of lle ln_flags can be also 2267 * saved in @pflags if @pflags is non-NULL. 2268 * 2269 * If destination LLE does not exists or lle state modification 2270 * is required, call "slow" version. 2271 * 2272 * Return values: 2273 * - 0 on success (address copied to buffer). 2274 * - EWOULDBLOCK (no local error, but address is still unresolved) 2275 * - other errors (alloc failure, etc) 2276 */ 2277 int 2278 nd6_resolve(struct ifnet *ifp, int gw_flags, struct mbuf *m, 2279 const struct sockaddr *sa_dst, u_char *desten, uint32_t *pflags, 2280 struct llentry **plle) 2281 { 2282 struct llentry *ln = NULL; 2283 const struct sockaddr_in6 *dst6; 2284 2285 NET_EPOCH_ASSERT(); 2286 2287 if (pflags != NULL) 2288 *pflags = 0; 2289 2290 dst6 = (const struct sockaddr_in6 *)sa_dst; 2291 2292 /* discard the packet if IPv6 operation is disabled on the interface */ 2293 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { 2294 m_freem(m); 2295 return (ENETDOWN); /* better error? */ 2296 } 2297 2298 if (m != NULL && m->m_flags & M_MCAST) { 2299 switch (ifp->if_type) { 2300 case IFT_ETHER: 2301 case IFT_L2VLAN: 2302 case IFT_BRIDGE: 2303 ETHER_MAP_IPV6_MULTICAST(&dst6->sin6_addr, 2304 desten); 2305 return (0); 2306 default: 2307 m_freem(m); 2308 return (EAFNOSUPPORT); 2309 } 2310 } 2311 2312 int family = gw_flags >> 16; 2313 int lookup_flags = plle ? LLE_EXCLUSIVE : LLE_UNLOCKED; 2314 ln = nd6_lookup(&dst6->sin6_addr, LLE_SF(family, lookup_flags), ifp); 2315 if (ln != NULL && (ln->r_flags & RLLE_VALID) != 0) { 2316 /* Entry found, let's copy lle info */ 2317 bcopy(ln->r_linkdata, desten, ln->r_hdrlen); 2318 if (pflags != NULL) 2319 *pflags = LLE_VALID | (ln->r_flags & RLLE_IFADDR); 2320 llentry_provide_feedback(ln); 2321 if (plle) { 2322 LLE_ADDREF(ln); 2323 *plle = ln; 2324 LLE_WUNLOCK(ln); 2325 } 2326 return (0); 2327 } else if (plle && ln) 2328 LLE_WUNLOCK(ln); 2329 2330 return (nd6_resolve_slow(ifp, family, 0, m, dst6, desten, pflags, plle)); 2331 } 2332 2333 /* 2334 * Finds or creates a new llentry for @addr and @family. 2335 * Returns wlocked llentry or NULL. 2336 * 2337 * 2338 * Child LLEs. 2339 * 2340 * Do not have their own state machine (gets marked as static) 2341 * settimer bails out for child LLEs just in case. 2342 * 2343 * Locking order: parent lle gets locked first, chen goes the child. 2344 */ 2345 static __noinline struct llentry * 2346 nd6_get_llentry(struct ifnet *ifp, const struct in6_addr *addr, int family) 2347 { 2348 struct llentry *child_lle = NULL; 2349 struct llentry *lle, *lle_tmp; 2350 2351 lle = nd6_alloc(addr, 0, ifp); 2352 if (lle != NULL && family != AF_INET6) { 2353 child_lle = nd6_alloc(addr, 0, ifp); 2354 if (child_lle == NULL) { 2355 lltable_free_entry(LLTABLE6(ifp), lle); 2356 return (NULL); 2357 } 2358 child_lle->r_family = family; 2359 child_lle->la_flags |= LLE_CHILD | LLE_STATIC; 2360 child_lle->ln_state = ND6_LLINFO_INCOMPLETE; 2361 } 2362 2363 if (lle == NULL) { 2364 char ip6buf[INET6_ADDRSTRLEN]; 2365 log(LOG_DEBUG, 2366 "nd6_get_llentry: can't allocate llinfo for %s " 2367 "(ln=%p)\n", 2368 ip6_sprintf(ip6buf, addr), lle); 2369 return (NULL); 2370 } 2371 2372 IF_AFDATA_WLOCK(ifp); 2373 LLE_WLOCK(lle); 2374 /* Prefer any existing entry over newly-created one */ 2375 lle_tmp = nd6_lookup(addr, LLE_SF(AF_INET6, LLE_EXCLUSIVE), ifp); 2376 if (lle_tmp == NULL) 2377 lltable_link_entry(LLTABLE6(ifp), lle); 2378 else { 2379 lltable_free_entry(LLTABLE6(ifp), lle); 2380 lle = lle_tmp; 2381 } 2382 if (child_lle != NULL) { 2383 /* Check if child lle for the same family exists */ 2384 lle_tmp = llentry_lookup_family(lle, child_lle->r_family); 2385 LLE_WLOCK(child_lle); 2386 if (lle_tmp == NULL) { 2387 /* Attach */ 2388 lltable_link_child_entry(lle, child_lle); 2389 } else { 2390 /* child lle already exists, free newly-created one */ 2391 lltable_free_entry(LLTABLE6(ifp), child_lle); 2392 child_lle = lle_tmp; 2393 } 2394 LLE_WUNLOCK(lle); 2395 lle = child_lle; 2396 } 2397 IF_AFDATA_WUNLOCK(ifp); 2398 return (lle); 2399 } 2400 2401 /* 2402 * Do L2 address resolution for @sa_dst address. Stores found 2403 * address in @desten buffer. Copy of lle ln_flags can be also 2404 * saved in @pflags if @pflags is non-NULL. 2405 * 2406 * Heavy version. 2407 * Function assume that destination LLE does not exist, 2408 * is invalid or stale, so LLE_EXCLUSIVE lock needs to be acquired. 2409 * 2410 * Set noinline to be dtrace-friendly 2411 */ 2412 static __noinline int 2413 nd6_resolve_slow(struct ifnet *ifp, int family, int flags, struct mbuf *m, 2414 const struct sockaddr_in6 *dst, u_char *desten, uint32_t *pflags, 2415 struct llentry **plle) 2416 { 2417 struct llentry *lle = NULL; 2418 struct in6_addr *psrc, src; 2419 int send_ns, ll_len; 2420 char *lladdr; 2421 2422 NET_EPOCH_ASSERT(); 2423 2424 /* 2425 * Address resolution or Neighbor Unreachability Detection 2426 * for the next hop. 2427 * At this point, the destination of the packet must be a unicast 2428 * or an anycast address(i.e. not a multicast). 2429 */ 2430 lle = nd6_lookup(&dst->sin6_addr, LLE_SF(family, LLE_EXCLUSIVE), ifp); 2431 if ((lle == NULL) && nd6_is_addr_neighbor(dst, ifp)) { 2432 /* 2433 * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), 2434 * the condition below is not very efficient. But we believe 2435 * it is tolerable, because this should be a rare case. 2436 */ 2437 lle = nd6_get_llentry(ifp, &dst->sin6_addr, family); 2438 } 2439 2440 if (lle == NULL) { 2441 m_freem(m); 2442 return (ENOBUFS); 2443 } 2444 2445 LLE_WLOCK_ASSERT(lle); 2446 2447 /* 2448 * The first time we send a packet to a neighbor whose entry is 2449 * STALE, we have to change the state to DELAY and a sets a timer to 2450 * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do 2451 * neighbor unreachability detection on expiration. 2452 * (RFC 2461 7.3.3) 2453 */ 2454 if ((!(lle->la_flags & LLE_CHILD)) && (lle->ln_state == ND6_LLINFO_STALE)) 2455 nd6_llinfo_setstate(lle, ND6_LLINFO_DELAY); 2456 2457 /* 2458 * If the neighbor cache entry has a state other than INCOMPLETE 2459 * (i.e. its link-layer address is already resolved), just 2460 * send the packet. 2461 */ 2462 if (lle->ln_state > ND6_LLINFO_INCOMPLETE) { 2463 if (flags & LLE_ADDRONLY) { 2464 lladdr = lle->ll_addr; 2465 ll_len = ifp->if_addrlen; 2466 } else { 2467 lladdr = lle->r_linkdata; 2468 ll_len = lle->r_hdrlen; 2469 } 2470 bcopy(lladdr, desten, ll_len); 2471 if (pflags != NULL) 2472 *pflags = lle->la_flags; 2473 if (plle) { 2474 LLE_ADDREF(lle); 2475 *plle = lle; 2476 } 2477 LLE_WUNLOCK(lle); 2478 return (0); 2479 } 2480 2481 /* 2482 * There is a neighbor cache entry, but no ethernet address 2483 * response yet. Append this latest packet to the end of the 2484 * packet queue in the mbuf. When it exceeds nd6_maxqueuelen, 2485 * the oldest packet in the queue will be removed. 2486 */ 2487 2488 if (lle->la_hold != NULL) { 2489 struct mbuf *m_hold; 2490 int i; 2491 2492 i = 0; 2493 for (m_hold = lle->la_hold; m_hold; m_hold = m_hold->m_nextpkt){ 2494 i++; 2495 if (m_hold->m_nextpkt == NULL) { 2496 m_hold->m_nextpkt = m; 2497 break; 2498 } 2499 } 2500 while (i >= V_nd6_maxqueuelen) { 2501 m_hold = lle->la_hold; 2502 lle->la_hold = lle->la_hold->m_nextpkt; 2503 m_freem(m_hold); 2504 i--; 2505 } 2506 } else { 2507 lle->la_hold = m; 2508 } 2509 2510 /* 2511 * If there has been no NS for the neighbor after entering the 2512 * INCOMPLETE state, send the first solicitation. 2513 * Note that for newly-created lle la_asked will be 0, 2514 * so we will transition from ND6_LLINFO_NOSTATE to 2515 * ND6_LLINFO_INCOMPLETE state here. 2516 */ 2517 psrc = NULL; 2518 send_ns = 0; 2519 2520 /* If we have child lle, switch to the parent to send NS */ 2521 if (lle->la_flags & LLE_CHILD) { 2522 struct llentry *lle_parent = lle->lle_parent; 2523 LLE_WUNLOCK(lle); 2524 lle = lle_parent; 2525 LLE_WLOCK(lle); 2526 } 2527 if (lle->la_asked == 0) { 2528 lle->la_asked++; 2529 send_ns = 1; 2530 psrc = nd6_llinfo_get_holdsrc(lle, &src); 2531 2532 nd6_llinfo_setstate(lle, ND6_LLINFO_INCOMPLETE); 2533 } 2534 LLE_WUNLOCK(lle); 2535 if (send_ns != 0) 2536 nd6_ns_output(ifp, psrc, NULL, &dst->sin6_addr, NULL); 2537 2538 return (EWOULDBLOCK); 2539 } 2540 2541 /* 2542 * Do L2 address resolution for @sa_dst address. Stores found 2543 * address in @desten buffer. Copy of lle ln_flags can be also 2544 * saved in @pflags if @pflags is non-NULL. 2545 * 2546 * Return values: 2547 * - 0 on success (address copied to buffer). 2548 * - EWOULDBLOCK (no local error, but address is still unresolved) 2549 * - other errors (alloc failure, etc) 2550 */ 2551 int 2552 nd6_resolve_addr(struct ifnet *ifp, int flags, const struct sockaddr *dst, 2553 char *desten, uint32_t *pflags) 2554 { 2555 int error; 2556 2557 flags |= LLE_ADDRONLY; 2558 error = nd6_resolve_slow(ifp, AF_INET6, flags, NULL, 2559 (const struct sockaddr_in6 *)dst, desten, pflags, NULL); 2560 return (error); 2561 } 2562 2563 int 2564 nd6_flush_holdchain(struct ifnet *ifp, struct llentry *lle, struct mbuf *chain) 2565 { 2566 struct mbuf *m, *m_head; 2567 struct sockaddr_in6 dst6; 2568 int error = 0; 2569 2570 NET_EPOCH_ASSERT(); 2571 2572 struct route_in6 ro = { 2573 .ro_prepend = lle->r_linkdata, 2574 .ro_plen = lle->r_hdrlen, 2575 }; 2576 2577 lltable_fill_sa_entry(lle, (struct sockaddr *)&dst6); 2578 m_head = chain; 2579 2580 while (m_head) { 2581 m = m_head; 2582 m_head = m_head->m_nextpkt; 2583 m->m_nextpkt = NULL; 2584 error = nd6_output_ifp(ifp, ifp, m, &dst6, (struct route *)&ro); 2585 } 2586 2587 /* 2588 * XXX 2589 * note that intermediate errors are blindly ignored 2590 */ 2591 return (error); 2592 } 2593 2594 __noinline void 2595 nd6_flush_children_holdchain(struct ifnet *ifp, struct llentry *lle) 2596 { 2597 struct llentry *child_lle; 2598 struct mbuf *chain; 2599 2600 NET_EPOCH_ASSERT(); 2601 2602 CK_SLIST_FOREACH(child_lle, &lle->lle_children, lle_child_next) { 2603 LLE_WLOCK(child_lle); 2604 chain = nd6_grab_holdchain(child_lle); 2605 LLE_WUNLOCK(child_lle); 2606 nd6_flush_holdchain(ifp, child_lle, chain); 2607 } 2608 } 2609 2610 static int 2611 nd6_need_cache(struct ifnet *ifp) 2612 { 2613 /* 2614 * XXX: we currently do not make neighbor cache on any interface 2615 * other than Ethernet and GIF. 2616 * 2617 * RFC2893 says: 2618 * - unidirectional tunnels needs no ND 2619 */ 2620 switch (ifp->if_type) { 2621 case IFT_ETHER: 2622 case IFT_IEEE1394: 2623 case IFT_L2VLAN: 2624 case IFT_INFINIBAND: 2625 case IFT_BRIDGE: 2626 case IFT_PROPVIRTUAL: 2627 return (1); 2628 default: 2629 return (0); 2630 } 2631 } 2632 2633 /* 2634 * Add pernament ND6 link-layer record for given 2635 * interface address. 2636 * 2637 * Very similar to IPv4 arp_ifinit(), but: 2638 * 1) IPv6 DAD is performed in different place 2639 * 2) It is called by IPv6 protocol stack in contrast to 2640 * arp_ifinit() which is typically called in SIOCSIFADDR 2641 * driver ioctl handler. 2642 * 2643 */ 2644 int 2645 nd6_add_ifa_lle(struct in6_ifaddr *ia) 2646 { 2647 struct ifnet *ifp; 2648 struct llentry *ln, *ln_tmp; 2649 struct sockaddr *dst; 2650 2651 ifp = ia->ia_ifa.ifa_ifp; 2652 if (nd6_need_cache(ifp) == 0) 2653 return (0); 2654 2655 dst = (struct sockaddr *)&ia->ia_addr; 2656 ln = lltable_alloc_entry(LLTABLE6(ifp), LLE_IFADDR, dst); 2657 if (ln == NULL) 2658 return (ENOBUFS); 2659 2660 IF_AFDATA_WLOCK(ifp); 2661 LLE_WLOCK(ln); 2662 /* Unlink any entry if exists */ 2663 ln_tmp = lla_lookup(LLTABLE6(ifp), LLE_SF(AF_INET6, LLE_EXCLUSIVE), dst); 2664 if (ln_tmp != NULL) 2665 lltable_unlink_entry(LLTABLE6(ifp), ln_tmp); 2666 lltable_link_entry(LLTABLE6(ifp), ln); 2667 IF_AFDATA_WUNLOCK(ifp); 2668 2669 if (ln_tmp != NULL) 2670 EVENTHANDLER_INVOKE(lle_event, ln_tmp, LLENTRY_EXPIRED); 2671 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 2672 2673 LLE_WUNLOCK(ln); 2674 if (ln_tmp != NULL) 2675 llentry_free(ln_tmp); 2676 2677 return (0); 2678 } 2679 2680 /* 2681 * Removes either all lle entries for given @ia, or lle 2682 * corresponding to @ia address. 2683 */ 2684 void 2685 nd6_rem_ifa_lle(struct in6_ifaddr *ia, int all) 2686 { 2687 struct sockaddr_in6 mask, addr; 2688 struct sockaddr *saddr, *smask; 2689 struct ifnet *ifp; 2690 2691 ifp = ia->ia_ifa.ifa_ifp; 2692 memcpy(&addr, &ia->ia_addr, sizeof(ia->ia_addr)); 2693 memcpy(&mask, &ia->ia_prefixmask, sizeof(ia->ia_prefixmask)); 2694 saddr = (struct sockaddr *)&addr; 2695 smask = (struct sockaddr *)&mask; 2696 2697 if (all != 0) 2698 lltable_prefix_free(AF_INET6, saddr, smask, LLE_STATIC); 2699 else 2700 lltable_delete_addr(LLTABLE6(ifp), LLE_IFADDR, saddr); 2701 } 2702 2703 static void 2704 clear_llinfo_pqueue(struct llentry *ln) 2705 { 2706 struct mbuf *m_hold, *m_hold_next; 2707 2708 for (m_hold = ln->la_hold; m_hold; m_hold = m_hold_next) { 2709 m_hold_next = m_hold->m_nextpkt; 2710 m_freem(m_hold); 2711 } 2712 2713 ln->la_hold = NULL; 2714 } 2715 2716 static int 2717 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS) 2718 { 2719 struct in6_prefix p; 2720 struct sockaddr_in6 s6; 2721 struct nd_prefix *pr; 2722 struct nd_pfxrouter *pfr; 2723 time_t maxexpire; 2724 int error; 2725 char ip6buf[INET6_ADDRSTRLEN]; 2726 2727 if (req->newptr) 2728 return (EPERM); 2729 2730 error = sysctl_wire_old_buffer(req, 0); 2731 if (error != 0) 2732 return (error); 2733 2734 bzero(&p, sizeof(p)); 2735 p.origin = PR_ORIG_RA; 2736 bzero(&s6, sizeof(s6)); 2737 s6.sin6_family = AF_INET6; 2738 s6.sin6_len = sizeof(s6); 2739 2740 ND6_RLOCK(); 2741 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 2742 p.prefix = pr->ndpr_prefix; 2743 if (sa6_recoverscope(&p.prefix)) { 2744 log(LOG_ERR, "scope error in prefix list (%s)\n", 2745 ip6_sprintf(ip6buf, &p.prefix.sin6_addr)); 2746 /* XXX: press on... */ 2747 } 2748 p.raflags = pr->ndpr_raf; 2749 p.prefixlen = pr->ndpr_plen; 2750 p.vltime = pr->ndpr_vltime; 2751 p.pltime = pr->ndpr_pltime; 2752 p.if_index = pr->ndpr_ifp->if_index; 2753 if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2754 p.expire = 0; 2755 else { 2756 /* XXX: we assume time_t is signed. */ 2757 maxexpire = (-1) & 2758 ~((time_t)1 << ((sizeof(maxexpire) * 8) - 1)); 2759 if (pr->ndpr_vltime < maxexpire - pr->ndpr_lastupdate) 2760 p.expire = pr->ndpr_lastupdate + 2761 pr->ndpr_vltime + 2762 (time_second - time_uptime); 2763 else 2764 p.expire = maxexpire; 2765 } 2766 p.refcnt = pr->ndpr_addrcnt; 2767 p.flags = pr->ndpr_stateflags; 2768 p.advrtrs = 0; 2769 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) 2770 p.advrtrs++; 2771 error = SYSCTL_OUT(req, &p, sizeof(p)); 2772 if (error != 0) 2773 break; 2774 LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) { 2775 s6.sin6_addr = pfr->router->rtaddr; 2776 if (sa6_recoverscope(&s6)) 2777 log(LOG_ERR, 2778 "scope error in prefix list (%s)\n", 2779 ip6_sprintf(ip6buf, &pfr->router->rtaddr)); 2780 error = SYSCTL_OUT(req, &s6, sizeof(s6)); 2781 if (error != 0) 2782 goto out; 2783 } 2784 } 2785 out: 2786 ND6_RUNLOCK(); 2787 return (error); 2788 } 2789 SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist, 2790 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, 2791 NULL, 0, nd6_sysctl_prlist, "S,in6_prefix", 2792 "NDP prefix list"); 2793 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen, 2794 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, ""); 2795 SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, nd6_gctimer, 2796 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_gctimer), (60 * 60 * 24), ""); 2797