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.h,v 1.76 2001/12/18 02:10:31 itojun Exp $ 32 * $FreeBSD$ 33 */ 34 35#ifndef _NETINET6_ND6_H_ 36#define _NETINET6_ND6_H_ 37 38/* see net/route.h, or net/if_inarp.h */ 39#ifndef RTF_ANNOUNCE 40#define RTF_ANNOUNCE RTF_PROTO2 41#endif 42 43#include <sys/queue.h> 44#include <sys/callout.h> 45 46struct llentry; 47 48#define ND6_LLINFO_NOSTATE -2 49/* 50 * We don't need the WAITDELETE state any more, but we keep the definition 51 * in a comment line instead of removing it. This is necessary to avoid 52 * unintentionally reusing the value for another purpose, which might 53 * affect backward compatibility with old applications. 54 * (20000711 jinmei@kame.net) 55 */ 56/* #define ND6_LLINFO_WAITDELETE -1 */ 57#define ND6_LLINFO_INCOMPLETE 0 58#define ND6_LLINFO_REACHABLE 1 59#define ND6_LLINFO_STALE 2 60#define ND6_LLINFO_DELAY 3 61#define ND6_LLINFO_PROBE 4 62 63#define ND6_IS_LLINFO_PROBREACH(n) ((n)->ln_state > ND6_LLINFO_INCOMPLETE) 64#define ND6_LLINFO_PERMANENT(n) (((n)->la_expire == 0) && ((n)->ln_state > ND6_LLINFO_INCOMPLETE)) 65 66struct nd_ifinfo { 67 u_int32_t linkmtu; /* LinkMTU */ 68 u_int32_t maxmtu; /* Upper bound of LinkMTU */ 69 u_int32_t basereachable; /* BaseReachableTime */ 70 u_int32_t reachable; /* Reachable Time */ 71 u_int32_t retrans; /* Retrans Timer */ 72 u_int32_t flags; /* Flags */ 73 int recalctm; /* BaseReacable re-calculation timer */ 74 u_int8_t chlim; /* CurHopLimit */ 75 u_int8_t initialized; /* Flag to see the entry is initialized */ 76 /* the following 3 members are for privacy extension for addrconf */ 77 u_int8_t randomseed0[8]; /* upper 64 bits of MD5 digest */ 78 u_int8_t randomseed1[8]; /* lower 64 bits (usually the EUI64 IFID) */ 79 u_int8_t randomid[8]; /* current random ID */ 80}; 81 82#define ND6_IFF_PERFORMNUD 0x1 83#define ND6_IFF_ACCEPT_RTADV 0x2 84#define ND6_IFF_PREFER_SOURCE 0x4 /* Not used in FreeBSD. */ 85#define ND6_IFF_IFDISABLED 0x8 /* IPv6 operation is disabled due to 86 * DAD failure. (XXX: not ND-specific) 87 */ 88#define ND6_IFF_DONT_SET_IFROUTE 0x10 89#define ND6_IFF_AUTO_LINKLOCAL 0x20 90#define ND6_IFF_NO_RADR 0x40 91#define ND6_IFF_NO_PREFER_IFACE 0x80 /* XXX: not related to ND. */ 92#define ND6_IFF_NO_DAD 0x100 93 94#ifdef _KERNEL 95#define ND_IFINFO(ifp) \ 96 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->nd_ifinfo) 97#define IN6_LINKMTU(ifp) \ 98 ((ND_IFINFO(ifp)->linkmtu && ND_IFINFO(ifp)->linkmtu < (ifp)->if_mtu) \ 99 ? ND_IFINFO(ifp)->linkmtu \ 100 : ((ND_IFINFO(ifp)->maxmtu && ND_IFINFO(ifp)->maxmtu < (ifp)->if_mtu) \ 101 ? ND_IFINFO(ifp)->maxmtu : (ifp)->if_mtu)) 102#endif 103 104struct in6_nbrinfo { 105 char ifname[IFNAMSIZ]; /* if name, e.g. "en0" */ 106 struct in6_addr addr; /* IPv6 address of the neighbor */ 107 long asked; /* number of queries already sent for this addr */ 108 int isrouter; /* if it acts as a router */ 109 int state; /* reachability state */ 110 int expire; /* lifetime for NDP state transition */ 111}; 112 113#define DRLSTSIZ 10 114#define PRLSTSIZ 10 115struct in6_drlist { 116 char ifname[IFNAMSIZ]; 117 struct { 118 struct in6_addr rtaddr; 119 u_char flags; 120 u_short rtlifetime; 121 u_long expire; 122 u_short if_index; 123 } defrouter[DRLSTSIZ]; 124}; 125 126struct in6_defrouter { 127 struct sockaddr_in6 rtaddr; 128 u_char flags; 129 u_short rtlifetime; 130 u_long expire; 131 u_short if_index; 132}; 133 134#ifdef _KERNEL 135struct in6_oprlist { 136 char ifname[IFNAMSIZ]; 137 struct { 138 struct in6_addr prefix; 139 struct prf_ra raflags; 140 u_char prefixlen; 141 u_char origin; 142 u_long vltime; 143 u_long pltime; 144 u_long expire; 145 u_short if_index; 146 u_short advrtrs; /* number of advertisement routers */ 147 struct in6_addr advrtr[DRLSTSIZ]; /* XXX: explicit limit */ 148 } prefix[PRLSTSIZ]; 149}; 150#endif 151 152struct in6_prlist { 153 char ifname[IFNAMSIZ]; 154 struct { 155 struct in6_addr prefix; 156 struct prf_ra raflags; 157 u_char prefixlen; 158 u_char origin; 159 u_int32_t vltime; 160 u_int32_t pltime; 161 time_t expire; 162 u_short if_index; 163 u_short advrtrs; /* number of advertisement routers */ 164 struct in6_addr advrtr[DRLSTSIZ]; /* XXX: explicit limit */ 165 } prefix[PRLSTSIZ]; 166}; 167 168struct in6_prefix { 169 struct sockaddr_in6 prefix; 170 struct prf_ra raflags; 171 u_char prefixlen; 172 u_char origin; 173 u_int32_t vltime; 174 u_int32_t pltime; 175 time_t expire; 176 u_int32_t flags; 177 int refcnt; 178 u_short if_index; 179 u_short advrtrs; /* number of advertisement routers */ 180 /* struct sockaddr_in6 advrtr[] */ 181}; 182 183#ifdef _KERNEL 184struct in6_ondireq { 185 char ifname[IFNAMSIZ]; 186 struct { 187 u_int32_t linkmtu; /* LinkMTU */ 188 u_int32_t maxmtu; /* Upper bound of LinkMTU */ 189 u_int32_t basereachable; /* BaseReachableTime */ 190 u_int32_t reachable; /* Reachable Time */ 191 u_int32_t retrans; /* Retrans Timer */ 192 u_int32_t flags; /* Flags */ 193 int recalctm; /* BaseReacable re-calculation timer */ 194 u_int8_t chlim; /* CurHopLimit */ 195 u_int8_t receivedra; 196 } ndi; 197}; 198#endif 199 200struct in6_ndireq { 201 char ifname[IFNAMSIZ]; 202 struct nd_ifinfo ndi; 203}; 204 205struct in6_ndifreq { 206 char ifname[IFNAMSIZ]; 207 u_long ifindex; 208}; 209 210/* Prefix status */ 211#define NDPRF_ONLINK 0x1 212#define NDPRF_DETACHED 0x2 213 214/* protocol constants */ 215#define MAX_RTR_SOLICITATION_DELAY 1 /* 1sec */ 216#define RTR_SOLICITATION_INTERVAL 4 /* 4sec */ 217#define MAX_RTR_SOLICITATIONS 3 218 219#define ND6_INFINITE_LIFETIME 0xffffffff 220 221#ifdef _KERNEL 222/* node constants */ 223#define MAX_REACHABLE_TIME 3600000 /* msec */ 224#define REACHABLE_TIME 30000 /* msec */ 225#define RETRANS_TIMER 1000 /* msec */ 226#define MIN_RANDOM_FACTOR 512 /* 1024 * 0.5 */ 227#define MAX_RANDOM_FACTOR 1536 /* 1024 * 1.5 */ 228#define DEF_TEMP_VALID_LIFETIME 604800 /* 1 week */ 229#define DEF_TEMP_PREFERRED_LIFETIME 86400 /* 1 day */ 230#define TEMPADDR_REGEN_ADVANCE 5 /* sec */ 231#define MAX_TEMP_DESYNC_FACTOR 600 /* 10 min */ 232#define ND_COMPUTE_RTIME(x) \ 233 (((MIN_RANDOM_FACTOR * (x >> 10)) + (arc4random() & \ 234 ((MAX_RANDOM_FACTOR - MIN_RANDOM_FACTOR) * (x >> 10)))) /1000) 235 236TAILQ_HEAD(nd_drhead, nd_defrouter); 237struct nd_defrouter { 238 TAILQ_ENTRY(nd_defrouter) dr_entry; 239 struct in6_addr rtaddr; 240 u_char raflags; /* flags on RA message */ 241 u_short rtlifetime; 242 u_long expire; 243 struct ifnet *ifp; 244 int installed; /* is installed into kernel routing table */ 245 u_int refcnt; 246}; 247 248struct nd_prefixctl { 249 struct ifnet *ndpr_ifp; 250 251 /* prefix */ 252 struct sockaddr_in6 ndpr_prefix; 253 u_char ndpr_plen; 254 255 u_int32_t ndpr_vltime; /* advertised valid lifetime */ 256 u_int32_t ndpr_pltime; /* advertised preferred lifetime */ 257 258 struct prf_ra ndpr_flags; 259}; 260 261LIST_HEAD(nd_prhead, nd_prefix); 262struct nd_prefix { 263 struct ifnet *ndpr_ifp; 264 LIST_ENTRY(nd_prefix) ndpr_entry; 265 struct sockaddr_in6 ndpr_prefix; /* prefix */ 266 struct in6_addr ndpr_mask; /* netmask derived from the prefix */ 267 268 u_int32_t ndpr_vltime; /* advertised valid lifetime */ 269 u_int32_t ndpr_pltime; /* advertised preferred lifetime */ 270 271 time_t ndpr_expire; /* expiration time of the prefix */ 272 time_t ndpr_preferred; /* preferred time of the prefix */ 273 time_t ndpr_lastupdate; /* reception time of last advertisement */ 274 275 struct prf_ra ndpr_flags; 276 u_int32_t ndpr_stateflags; /* actual state flags */ 277 /* list of routers that advertise the prefix: */ 278 LIST_HEAD(pr_rtrhead, nd_pfxrouter) ndpr_advrtrs; 279 u_char ndpr_plen; 280 int ndpr_addrcnt; /* count of derived addresses */ 281 volatile u_int ndpr_refcnt; 282}; 283 284#define ndpr_raf ndpr_flags 285#define ndpr_raf_onlink ndpr_flags.onlink 286#define ndpr_raf_auto ndpr_flags.autonomous 287#define ndpr_raf_router ndpr_flags.router 288 289/* 290 * Message format for use in obtaining information about prefixes 291 * from inet6 sysctl function 292 */ 293struct inet6_ndpr_msghdr { 294 u_short inpm_msglen; /* to skip over non-understood messages */ 295 u_char inpm_version; /* future binary compatibility */ 296 u_char inpm_type; /* message type */ 297 struct in6_addr inpm_prefix; 298 u_long prm_vltim; 299 u_long prm_pltime; 300 u_long prm_expire; 301 u_long prm_preferred; 302 struct in6_prflags prm_flags; 303 u_short prm_index; /* index for associated ifp */ 304 u_char prm_plen; /* length of prefix in bits */ 305}; 306 307#define prm_raf_onlink prm_flags.prf_ra.onlink 308#define prm_raf_auto prm_flags.prf_ra.autonomous 309 310#define prm_statef_onlink prm_flags.prf_state.onlink 311 312#define prm_rrf_decrvalid prm_flags.prf_rr.decrvalid 313#define prm_rrf_decrprefd prm_flags.prf_rr.decrprefd 314 315struct nd_pfxrouter { 316 LIST_ENTRY(nd_pfxrouter) pfr_entry; 317 struct nd_defrouter *router; 318}; 319 320#ifdef MALLOC_DECLARE 321MALLOC_DECLARE(M_IP6NDP); 322#endif 323 324/* nd6.c */ 325VNET_DECLARE(int, nd6_prune); 326VNET_DECLARE(int, nd6_delay); 327VNET_DECLARE(int, nd6_umaxtries); 328VNET_DECLARE(int, nd6_mmaxtries); 329VNET_DECLARE(int, nd6_useloopback); 330VNET_DECLARE(int, nd6_maxnudhint); 331VNET_DECLARE(int, nd6_gctimer); 332VNET_DECLARE(struct nd_prhead, nd_prefix); 333VNET_DECLARE(int, nd6_debug); 334VNET_DECLARE(int, nd6_onlink_ns_rfc4861); 335#define V_nd6_prune VNET(nd6_prune) 336#define V_nd6_delay VNET(nd6_delay) 337#define V_nd6_umaxtries VNET(nd6_umaxtries) 338#define V_nd6_mmaxtries VNET(nd6_mmaxtries) 339#define V_nd6_useloopback VNET(nd6_useloopback) 340#define V_nd6_maxnudhint VNET(nd6_maxnudhint) 341#define V_nd6_gctimer VNET(nd6_gctimer) 342#define V_nd_prefix VNET(nd_prefix) 343#define V_nd6_debug VNET(nd6_debug) 344#define V_nd6_onlink_ns_rfc4861 VNET(nd6_onlink_ns_rfc4861) 345 346/* Lock for the prefix and default router lists. */ 347VNET_DECLARE(struct rwlock, nd6_lock); 348VNET_DECLARE(uint64_t, nd6_list_genid); 349#define V_nd6_lock VNET(nd6_lock) 350#define V_nd6_list_genid VNET(nd6_list_genid) 351 352#define ND6_RLOCK() rw_rlock(&V_nd6_lock) 353#define ND6_RUNLOCK() rw_runlock(&V_nd6_lock) 354#define ND6_WLOCK() rw_wlock(&V_nd6_lock) 355#define ND6_WUNLOCK() rw_wunlock(&V_nd6_lock) 356#define ND6_TRY_UPGRADE() rw_try_upgrade(&V_nd6_lock) 357#define ND6_WLOCK_ASSERT() rw_assert(&V_nd6_lock, RA_WLOCKED) 358#define ND6_RLOCK_ASSERT() rw_assert(&V_nd6_lock, RA_RLOCKED) 359#define ND6_LOCK_ASSERT() rw_assert(&V_nd6_lock, RA_LOCKED) 360#define ND6_UNLOCK_ASSERT() rw_assert(&V_nd6_lock, RA_UNLOCKED) 361 362/* Mutex for prefix onlink/offlink transitions. */ 363VNET_DECLARE(struct mtx, nd6_onlink_mtx); 364#define V_nd6_onlink_mtx VNET(nd6_onlink_mtx) 365 366#define ND6_ONLINK_LOCK() mtx_lock(&V_nd6_onlink_mtx) 367#define ND6_ONLINK_TRYLOCK() mtx_trylock(&V_nd6_onlink_mtx) 368#define ND6_ONLINK_UNLOCK() mtx_unlock(&V_nd6_onlink_mtx) 369#define ND6_ONLINK_LOCK_ASSERT() mtx_assert(&V_nd6_onlink_mtx, MA_OWNED) 370#define ND6_ONLINK_UNLOCK_ASSERT() mtx_assert(&V_nd6_onlink_mtx, MA_NOTOWNED) 371 372#define nd6log(x) do { if (V_nd6_debug) log x; } while (/*CONSTCOND*/ 0) 373 374/* nd6_rtr.c */ 375VNET_DECLARE(int, nd6_defifindex); 376VNET_DECLARE(int, ip6_desync_factor); /* seconds */ 377VNET_DECLARE(u_int32_t, ip6_temp_preferred_lifetime); /* seconds */ 378VNET_DECLARE(u_int32_t, ip6_temp_valid_lifetime); /* seconds */ 379VNET_DECLARE(int, ip6_temp_regen_advance); /* seconds */ 380#define V_nd6_defifindex VNET(nd6_defifindex) 381#define V_ip6_desync_factor VNET(ip6_desync_factor) 382#define V_ip6_temp_preferred_lifetime VNET(ip6_temp_preferred_lifetime) 383#define V_ip6_temp_valid_lifetime VNET(ip6_temp_valid_lifetime) 384#define V_ip6_temp_regen_advance VNET(ip6_temp_regen_advance) 385 386union nd_opts { 387 struct nd_opt_hdr *nd_opt_array[16]; /* max = ND_OPT_NONCE */ 388 struct { 389 struct nd_opt_hdr *zero; 390 struct nd_opt_hdr *src_lladdr; 391 struct nd_opt_hdr *tgt_lladdr; 392 struct nd_opt_prefix_info *pi_beg; /* multiple opts, start */ 393 struct nd_opt_rd_hdr *rh; 394 struct nd_opt_mtu *mtu; 395 struct nd_opt_hdr *__res6; 396 struct nd_opt_hdr *__res7; 397 struct nd_opt_hdr *__res8; 398 struct nd_opt_hdr *__res9; 399 struct nd_opt_hdr *__res10; 400 struct nd_opt_hdr *__res11; 401 struct nd_opt_hdr *__res12; 402 struct nd_opt_hdr *__res13; 403 struct nd_opt_nonce *nonce; 404 struct nd_opt_hdr *__res15; 405 struct nd_opt_hdr *search; /* multiple opts */ 406 struct nd_opt_hdr *last; /* multiple opts */ 407 int done; 408 struct nd_opt_prefix_info *pi_end;/* multiple opts, end */ 409 } nd_opt_each; 410}; 411#define nd_opts_src_lladdr nd_opt_each.src_lladdr 412#define nd_opts_tgt_lladdr nd_opt_each.tgt_lladdr 413#define nd_opts_pi nd_opt_each.pi_beg 414#define nd_opts_pi_end nd_opt_each.pi_end 415#define nd_opts_rh nd_opt_each.rh 416#define nd_opts_mtu nd_opt_each.mtu 417#define nd_opts_nonce nd_opt_each.nonce 418#define nd_opts_search nd_opt_each.search 419#define nd_opts_last nd_opt_each.last 420#define nd_opts_done nd_opt_each.done 421 422/* XXX: need nd6_var.h?? */ 423/* nd6.c */ 424void nd6_init(void); 425#ifdef VIMAGE 426void nd6_destroy(void); 427#endif 428struct nd_ifinfo *nd6_ifattach(struct ifnet *); 429void nd6_ifdetach(struct ifnet *, struct nd_ifinfo *); 430int nd6_is_addr_neighbor(const struct sockaddr_in6 *, struct ifnet *); 431void nd6_option_init(void *, int, union nd_opts *); 432struct nd_opt_hdr *nd6_option(union nd_opts *); 433int nd6_options(union nd_opts *); 434struct llentry *nd6_lookup(const struct in6_addr *, int, struct ifnet *); 435struct llentry *nd6_alloc(const struct in6_addr *, int, struct ifnet *); 436void nd6_setmtu(struct ifnet *); 437void nd6_llinfo_setstate(struct llentry *lle, int newstate); 438void nd6_timer(void *); 439void nd6_purge(struct ifnet *); 440int nd6_resolve_addr(struct ifnet *ifp, int flags, const struct sockaddr *dst, 441 char *desten, uint32_t *pflags); 442int nd6_resolve(struct ifnet *, int, struct mbuf *, 443 const struct sockaddr *, u_char *, uint32_t *, struct llentry **); 444int nd6_ioctl(u_long, caddr_t, struct ifnet *); 445void nd6_cache_lladdr(struct ifnet *, struct in6_addr *, 446 char *, int, int, int); 447void nd6_grab_holdchain(struct llentry *, struct mbuf **, 448 struct sockaddr_in6 *); 449int nd6_flush_holdchain(struct ifnet *, struct mbuf *, 450 struct sockaddr_in6 *); 451int nd6_add_ifa_lle(struct in6_ifaddr *); 452void nd6_rem_ifa_lle(struct in6_ifaddr *, int); 453int nd6_output_ifp(struct ifnet *, struct ifnet *, struct mbuf *, 454 struct sockaddr_in6 *, struct route *); 455 456/* nd6_nbr.c */ 457void nd6_na_input(struct mbuf *, int, int); 458void nd6_na_output(struct ifnet *, const struct in6_addr *, 459 const struct in6_addr *, u_long, int, struct sockaddr *); 460void nd6_ns_input(struct mbuf *, int, int); 461void nd6_ns_output(struct ifnet *, const struct in6_addr *, 462 const struct in6_addr *, const struct in6_addr *, uint8_t *); 463caddr_t nd6_ifptomac(struct ifnet *); 464void nd6_dad_init(void); 465void nd6_dad_start(struct ifaddr *, int); 466void nd6_dad_stop(struct ifaddr *); 467 468/* nd6_rtr.c */ 469void nd6_rs_input(struct mbuf *, int, int); 470void nd6_ra_input(struct mbuf *, int, int); 471struct nd_defrouter *defrouter_lookup(struct in6_addr *, struct ifnet *); 472struct nd_defrouter *defrouter_lookup_locked(struct in6_addr *, struct ifnet *); 473void defrouter_reset(void); 474void defrouter_select_fib(int fibnum); 475void defrouter_select(void); 476void defrouter_ref(struct nd_defrouter *); 477void defrouter_rele(struct nd_defrouter *); 478bool defrouter_remove(struct in6_addr *, struct ifnet *); 479void defrouter_unlink(struct nd_defrouter *, struct nd_drhead *); 480void defrouter_del(struct nd_defrouter *); 481bool nd6_defrouter_list_empty(void); 482void nd6_defrouter_flush_all(void); 483void nd6_defrouter_purge(struct ifnet *); 484void nd6_defrouter_timer(void); 485void nd6_defrouter_init(void); 486int nd6_prelist_add(struct nd_prefixctl *, struct nd_defrouter *, 487 struct nd_prefix **); 488void nd6_prefix_unlink(struct nd_prefix *, struct nd_prhead *); 489void nd6_prefix_del(struct nd_prefix *); 490void nd6_prefix_ref(struct nd_prefix *); 491void nd6_prefix_rele(struct nd_prefix *); 492int nd6_prefix_onlink(struct nd_prefix *); 493int nd6_prefix_offlink(struct nd_prefix *); 494void pfxlist_onlink_check(void); 495struct nd_prefix *nd6_prefix_lookup(struct nd_prefixctl *); 496void rt6_flush(struct in6_addr *, struct ifnet *); 497int nd6_setdefaultiface(int); 498int in6_tmpifadd(const struct in6_ifaddr *, int, int); 499 500#endif /* _KERNEL */ 501 502#endif /* _NETINET6_ND6_H_ */ 503