sys/netinet6/nd6.c

   1 /*      $FreeBSD$       */
   2 /*      $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $   */
   3
   4 /*-
   5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the project nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include "opt_inet.h"
  34 #include "opt_inet6.h"
  35 #include "opt_mac.h"
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/callout.h>
  40 #include <sys/mac.h>
  41 #include <sys/malloc.h>
  42 #include <sys/mbuf.h>
  43 #include <sys/socket.h>
  44 #include <sys/sockio.h>
  45 #include <sys/time.h>
  46 #include <sys/kernel.h>
  47 #include <sys/protosw.h>
  48 #include <sys/errno.h>
  49 #include <sys/syslog.h>
  50 #include <sys/queue.h>
  51 #include <sys/sysctl.h>
  52
  53 #include <net/if.h>
  54 #include <net/if_arc.h>
  55 #include <net/if_dl.h>
  56 #include <net/if_types.h>
  57 #include <net/if_atm.h>
  58 #include <net/iso88025.h>
  59 #include <net/fddi.h>
  60 #include <net/route.h>
  61
  62 #include <netinet/in.h>
  63 #include <netinet/if_ether.h>
  64 #include <netinet6/in6_var.h>
  65 #include <netinet/ip6.h>
  66 #include <netinet6/ip6_var.h>
  67 #include <netinet6/nd6.h>
  68 #include <netinet/icmp6.h>
  69
  70 #include <net/net_osdep.h>
  71
  72 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
  73 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
  74
  75 #define SIN6(s) ((struct sockaddr_in6 *)s)
  76 #define SDL(s) ((struct sockaddr_dl *)s)
  77
  78 /* timer values */
  79 int     nd6_prune       = 1;    /* walk list every 1 seconds */
  80 int     nd6_delay       = 5;    /* delay first probe time 5 second */
  81 int     nd6_umaxtries   = 3;    /* maximum unicast query */
  82 int     nd6_mmaxtries   = 3;    /* maximum multicast query */
  83 int     nd6_useloopback = 1;    /* use loopback interface for local traffic */
  84 int     nd6_gctimer     = (60 * 60 * 24); /* 1 day: garbage collection timer */
  85
  86 /* preventing too many loops in ND option parsing */
  87 int nd6_maxndopt = 10;  /* max # of ND options allowed */
  88
  89 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */
  90
  91 #ifdef ND6_DEBUG
  92 int nd6_debug = 1;
  93 #else
  94 int nd6_debug = 0;
  95 #endif
  96
  97 /* for debugging? */
  98 static int nd6_inuse, nd6_allocated;
  99
 100 struct llinfo_nd6 llinfo_nd6 = {&llinfo_nd6, &llinfo_nd6};
 101 struct nd_drhead nd_defrouter;
 102 struct nd_prhead nd_prefix = { 0 };
 103
 104 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL;
 105 static struct sockaddr_in6 all1_sa;
 106
 107 static int nd6_is_new_addr_neighbor __P((struct sockaddr_in6 *,
 108         struct ifnet *));
 109 static void nd6_setmtu0 __P((struct ifnet *, struct nd_ifinfo *));
 110 static void nd6_slowtimo __P((void *));
 111 static int regen_tmpaddr __P((struct in6_ifaddr *));
 112
 113 struct callout nd6_slowtimo_ch;
 114 struct callout nd6_timer_ch;
 115 extern struct callout in6_tmpaddrtimer_ch;
 116
 117 void
 118 nd6_init()
 119 {
 120         static int nd6_init_done = 0;
 121         int i;
 122
 123         if (nd6_init_done) {
 124                 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n");
 125                 return;
 126         }
 127
 128         all1_sa.sin6_family = AF_INET6;
 129         all1_sa.sin6_len = sizeof(struct sockaddr_in6);
 130         for (i = 0; i < sizeof(all1_sa.sin6_addr); i++)
 131                 all1_sa.sin6_addr.s6_addr[i] = 0xff;
 132
 133         /* initialization of the default router list */
 134         TAILQ_INIT(&nd_defrouter);
 135
 136         nd6_init_done = 1;
 137
 138         /* start timer */
 139         callout_init(&nd6_slowtimo_ch, 0);
 140         callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
 141             nd6_slowtimo, NULL);
 142 }
 143
 144 struct nd_ifinfo *
 145 nd6_ifattach(ifp)
 146         struct ifnet *ifp;
 147 {
 148         struct nd_ifinfo *nd;
 149
 150         nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK);
 151         bzero(nd, sizeof(*nd));
 152
 153         nd->initialized = 1;
 154
 155         nd->chlim = IPV6_DEFHLIM;
 156         nd->basereachable = REACHABLE_TIME;
 157         nd->reachable = ND_COMPUTE_RTIME(nd->basereachable);
 158         nd->retrans = RETRANS_TIMER;
 159         /*
 160          * Note that the default value of ip6_accept_rtadv is 0, which means
 161          * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV
 162          * here.
 163          */
 164         nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV);
 165
 166         /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
 167         nd6_setmtu0(ifp, nd);
 168
 169         return nd;
 170 }
 171
 172 void
 173 nd6_ifdetach(nd)
 174         struct nd_ifinfo *nd;
 175 {
 176
 177         free(nd, M_IP6NDP);
 178 }
 179
 180 /*
 181  * Reset ND level link MTU. This function is called when the physical MTU
 182  * changes, which means we might have to adjust the ND level MTU.
 183  */
 184 void
 185 nd6_setmtu(ifp)
 186         struct ifnet *ifp;
 187 {
 188
 189         nd6_setmtu0(ifp, ND_IFINFO(ifp));
 190 }
 191
 192 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
 193 void
 194 nd6_setmtu0(ifp, ndi)
 195         struct ifnet *ifp;
 196         struct nd_ifinfo *ndi;
 197 {
 198         u_int32_t omaxmtu;
 199
 200         omaxmtu = ndi->maxmtu;
 201
 202         switch (ifp->if_type) {
 203         case IFT_ARCNET:
 204                 ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */
 205                 break;
 206         case IFT_ETHER:
 207                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
 208                 break;
 209         case IFT_FDDI:
 210                 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); /* RFC2467 */
 211                 break;
 212         case IFT_ATM:
 213                 ndi->maxmtu = MIN(ATMMTU, ifp->if_mtu);
 214                 break;
 215         case IFT_IEEE1394:      /* XXX should be IEEE1394MTU(1500) */
 216                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
 217                 break;
 218 #ifdef IFT_IEEE80211
 219         case IFT_IEEE80211:     /* XXX should be IEEE80211MTU(1500) */
 220                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
 221                 break;
 222 #endif
 223          case IFT_ISO88025:
 224                  ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu);
 225                  break;
 226         default:
 227                 ndi->maxmtu = ifp->if_mtu;
 228                 break;
 229         }
 230
 231         /*
 232          * Decreasing the interface MTU under IPV6 minimum MTU may cause
 233          * undesirable situation.  We thus notify the operator of the change
 234          * explicitly.  The check for omaxmtu is necessary to restrict the
 235          * log to the case of changing the MTU, not initializing it.
 236          */
 237         if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) {
 238                 log(LOG_NOTICE, "nd6_setmtu0: "
 239                     "new link MTU on %s (%lu) is too small for IPv6\n",
 240                     if_name(ifp), (unsigned long)ndi->maxmtu);
 241         }
 242
 243         if (ndi->maxmtu > in6_maxmtu)
 244                 in6_setmaxmtu(); /* check all interfaces just in case */
 245
 246 #undef MIN
 247 }
 248
 249 void
 250 nd6_option_init(opt, icmp6len, ndopts)
 251         void *opt;
 252         int icmp6len;
 253         union nd_opts *ndopts;
 254 {
 255
 256         bzero(ndopts, sizeof(*ndopts));
 257         ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
 258         ndopts->nd_opts_last
 259                 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
 260
 261         if (icmp6len == 0) {
 262                 ndopts->nd_opts_done = 1;
 263                 ndopts->nd_opts_search = NULL;
 264         }
 265 }
 266
 267 /*
 268  * Take one ND option.
 269  */
 270 struct nd_opt_hdr *
 271 nd6_option(ndopts)
 272         union nd_opts *ndopts;
 273 {
 274         struct nd_opt_hdr *nd_opt;
 275         int olen;
 276
 277         if (!ndopts)
 278                 panic("ndopts == NULL in nd6_option");
 279         if (!ndopts->nd_opts_last)
 280                 panic("uninitialized ndopts in nd6_option");
 281         if (!ndopts->nd_opts_search)
 282                 return NULL;
 283         if (ndopts->nd_opts_done)
 284                 return NULL;
 285
 286         nd_opt = ndopts->nd_opts_search;
 287
 288         /* make sure nd_opt_len is inside the buffer */
 289         if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) {
 290                 bzero(ndopts, sizeof(*ndopts));
 291                 return NULL;
 292         }
 293
 294         olen = nd_opt->nd_opt_len << 3;
 295         if (olen == 0) {
 296                 /*
 297                  * Message validation requires that all included
 298                  * options have a length that is greater than zero.
 299                  */
 300                 bzero(ndopts, sizeof(*ndopts));
 301                 return NULL;
 302         }
 303
 304         ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen);
 305         if (ndopts->nd_opts_search > ndopts->nd_opts_last) {
 306                 /* option overruns the end of buffer, invalid */
 307                 bzero(ndopts, sizeof(*ndopts));
 308                 return NULL;
 309         } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) {
 310                 /* reached the end of options chain */
 311                 ndopts->nd_opts_done = 1;
 312                 ndopts->nd_opts_search = NULL;
 313         }
 314         return nd_opt;
 315 }
 316
 317 /*
 318  * Parse multiple ND options.
 319  * This function is much easier to use, for ND routines that do not need
 320  * multiple options of the same type.
 321  */
 322 int
 323 nd6_options(ndopts)
 324         union nd_opts *ndopts;
 325 {
 326         struct nd_opt_hdr *nd_opt;
 327         int i = 0;
 328
 329         if (!ndopts)
 330                 panic("ndopts == NULL in nd6_options");
 331         if (!ndopts->nd_opts_last)
 332                 panic("uninitialized ndopts in nd6_options");
 333         if (!ndopts->nd_opts_search)
 334                 return 0;
 335
 336         while (1) {
 337                 nd_opt = nd6_option(ndopts);
 338                 if (!nd_opt && !ndopts->nd_opts_last) {
 339                         /*
 340                          * Message validation requires that all included
 341                          * options have a length that is greater than zero.
 342                          */
 343                         icmp6stat.icp6s_nd_badopt++;
 344                         bzero(ndopts, sizeof(*ndopts));
 345                         return -1;
 346                 }
 347
 348                 if (!nd_opt)
 349                         goto skip1;
 350
 351                 switch (nd_opt->nd_opt_type) {
 352                 case ND_OPT_SOURCE_LINKADDR:
 353                 case ND_OPT_TARGET_LINKADDR:
 354                 case ND_OPT_MTU:
 355                 case ND_OPT_REDIRECTED_HEADER:
 356                         if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
 357                                 nd6log((LOG_INFO,
 358                                     "duplicated ND6 option found (type=%d)\n",
 359                                     nd_opt->nd_opt_type));
 360                                 /* XXX bark? */
 361                         } else {
 362                                 ndopts->nd_opt_array[nd_opt->nd_opt_type]
 363                                         = nd_opt;
 364                         }
 365                         break;
 366                 case ND_OPT_PREFIX_INFORMATION:
 367                         if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) {
 368                                 ndopts->nd_opt_array[nd_opt->nd_opt_type]
 369                                         = nd_opt;
 370                         }
 371                         ndopts->nd_opts_pi_end =
 372                                 (struct nd_opt_prefix_info *)nd_opt;
 373                         break;
 374                 default:
 375                         /*
 376                          * Unknown options must be silently ignored,
 377                          * to accomodate future extension to the protocol.
 378                          */
 379                         nd6log((LOG_DEBUG,
 380                             "nd6_options: unsupported option %d - "
 381                             "option ignored\n", nd_opt->nd_opt_type));
 382                 }
 383
 384 skip1:
 385                 i++;
 386                 if (i > nd6_maxndopt) {
 387                         icmp6stat.icp6s_nd_toomanyopt++;
 388                         nd6log((LOG_INFO, "too many loop in nd opt\n"));
 389                         break;
 390                 }
 391
 392                 if (ndopts->nd_opts_done)
 393                         break;
 394         }
 395
 396         return 0;
 397 }
 398
 399 /*
 400  * ND6 timer routine to expire default route list and prefix list
 401  */
 402 void
 403 nd6_timer(ignored_arg)
 404         void    *ignored_arg;
 405 {
 406         int s;
 407         struct llinfo_nd6 *ln;
 408         struct nd_defrouter *dr;
 409         struct nd_prefix *pr;
 410         struct ifnet *ifp;
 411         struct in6_ifaddr *ia6, *nia6;
 412         struct in6_addrlifetime *lt6;
 413
 414         s = splnet();
 415         callout_reset(&nd6_timer_ch, nd6_prune * hz,
 416             nd6_timer, NULL);
 417
 418         ln = llinfo_nd6.ln_next;
 419         while (ln && ln != &llinfo_nd6) {
 420                 struct rtentry *rt;
 421                 struct sockaddr_in6 *dst;
 422                 struct llinfo_nd6 *next = ln->ln_next;
 423                 /* XXX: used for the DELAY case only: */
 424                 struct nd_ifinfo *ndi = NULL;
 425
 426                 if ((rt = ln->ln_rt) == NULL) {
 427                         ln = next;
 428                         continue;
 429                 }
 430                 if ((ifp = rt->rt_ifp) == NULL) {
 431                         ln = next;
 432                         continue;
 433                 }
 434                 ndi = ND_IFINFO(ifp);
 435                 dst = (struct sockaddr_in6 *)rt_key(rt);
 436
 437                 if (ln->ln_expire > time_second) {
 438                         ln = next;
 439                         continue;
 440                 }
 441
 442                 /* sanity check */
 443                 if (!rt)
 444                         panic("rt=0 in nd6_timer(ln=%p)", ln);
 445                 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln)
 446                         panic("rt_llinfo(%p) is not equal to ln(%p)",
 447                               rt->rt_llinfo, ln);
 448                 if (!dst)
 449                         panic("dst=0 in nd6_timer(ln=%p)", ln);
 450
 451                 switch (ln->ln_state) {
 452                 case ND6_LLINFO_INCOMPLETE:
 453                         if (ln->ln_asked < nd6_mmaxtries) {
 454                                 ln->ln_asked++;
 455                                 ln->ln_expire = time_second +
 456                                         ND_IFINFO(ifp)->retrans / 1000;
 457                                 nd6_ns_output(ifp, NULL, &dst->sin6_addr,
 458                                         ln, 0);
 459                         } else {
 460                                 struct mbuf *m = ln->ln_hold;
 461                                 if (m) {
 462                                         if (rt->rt_ifp) {
 463                                                 /*
 464                                                  * Fake rcvif to make ICMP error
 465                                                  * more helpful in diagnosing
 466                                                  * for the receiver.
 467                                                  * XXX: should we consider
 468                                                  * older rcvif?
 469                                                  */
 470                                                 m->m_pkthdr.rcvif = rt->rt_ifp;
 471                                         }
 472                                         icmp6_error(m, ICMP6_DST_UNREACH,
 473                                                     ICMP6_DST_UNREACH_ADDR, 0);
 474                                         ln->ln_hold = NULL;
 475                                 }
 476                                 next = nd6_free(rt);
 477                         }
 478                         break;
 479                 case ND6_LLINFO_REACHABLE:
 480                         if (ln->ln_expire) {
 481                                 ln->ln_state = ND6_LLINFO_STALE;
 482                                 ln->ln_expire = time_second + nd6_gctimer;
 483                         }
 484                         break;
 485
 486                 case ND6_LLINFO_STALE:
 487                         /* Garbage Collection(RFC 2461 5.3) */
 488                         if (ln->ln_expire)
 489                                 next = nd6_free(rt);
 490                         break;
 491
 492                 case ND6_LLINFO_DELAY:
 493                         if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) {
 494                                 /* We need NUD */
 495                                 ln->ln_asked = 1;
 496                                 ln->ln_state = ND6_LLINFO_PROBE;
 497                                 ln->ln_expire = time_second +
 498                                         ndi->retrans / 1000;
 499                                 nd6_ns_output(ifp, &dst->sin6_addr,
 500                                               &dst->sin6_addr,
 501                                               ln, 0);
 502                         } else {
 503                                 ln->ln_state = ND6_LLINFO_STALE; /* XXX */
 504                                 ln->ln_expire = time_second + nd6_gctimer;
 505                         }
 506                         break;
 507                 case ND6_LLINFO_PROBE:
 508                         if (ln->ln_asked < nd6_umaxtries) {
 509                                 ln->ln_asked++;
 510                                 ln->ln_expire = time_second +
 511                                         ND_IFINFO(ifp)->retrans / 1000;
 512                                 nd6_ns_output(ifp, &dst->sin6_addr,
 513                                                &dst->sin6_addr, ln, 0);
 514                         } else {
 515                                 next = nd6_free(rt);
 516                         }
 517                         break;
 518                 }
 519                 ln = next;
 520         }
 521
 522         /* expire default router list */
 523         dr = TAILQ_FIRST(&nd_defrouter);
 524         while (dr) {
 525                 if (dr->expire && dr->expire < time_second) {
 526                         struct nd_defrouter *t;
 527                         t = TAILQ_NEXT(dr, dr_entry);
 528                         defrtrlist_del(dr);
 529                         dr = t;
 530                 } else {
 531                         dr = TAILQ_NEXT(dr, dr_entry);
 532                 }
 533         }
 534
 535         /*
 536          * expire interface addresses.
 537          * in the past the loop was inside prefix expiry processing.
 538          * However, from a stricter speci-confrmance standpoint, we should
 539          * rather separate address lifetimes and prefix lifetimes.
 540          */
 541   addrloop:
 542         for (ia6 = in6_ifaddr; ia6; ia6 = nia6) {
 543                 nia6 = ia6->ia_next;
 544                 /* check address lifetime */
 545                 lt6 = &ia6->ia6_lifetime;
 546                 if (IFA6_IS_INVALID(ia6)) {
 547                         int regen = 0;
 548
 549                         /*
 550                          * If the expiring address is temporary, try
 551                          * regenerating a new one.  This would be useful when
 552                          * we suspended a laptop PC, then turned it on after a
 553                          * period that could invalidate all temporary
 554                          * addresses.  Although we may have to restart the
 555                          * loop (see below), it must be after purging the
 556                          * address.  Otherwise, we'd see an infinite loop of
 557                          * regeneration.
 558                          */
 559                         if (ip6_use_tempaddr &&
 560                             (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
 561                                 if (regen_tmpaddr(ia6) == 0)
 562                                         regen = 1;
 563                         }
 564
 565                         in6_purgeaddr(&ia6->ia_ifa);
 566
 567                         if (regen)
 568                                 goto addrloop; /* XXX: see below */
 569                 }
 570                 if (IFA6_IS_DEPRECATED(ia6)) {
 571                         int oldflags = ia6->ia6_flags;
 572
 573                         ia6->ia6_flags |= IN6_IFF_DEPRECATED;
 574
 575                         /*
 576                          * If a temporary address has just become deprecated,
 577                          * regenerate a new one if possible.
 578                          */
 579                         if (ip6_use_tempaddr &&
 580                             (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
 581                             (oldflags & IN6_IFF_DEPRECATED) == 0) {
 582
 583                                 if (regen_tmpaddr(ia6) == 0) {
 584                                         /*
 585                                          * A new temporary address is
 586                                          * generated.
 587                                          * XXX: this means the address chain
 588                                          * has changed while we are still in
 589                                          * the loop.  Although the change
 590                                          * would not cause disaster (because
 591                                          * it's not a deletion, but an
 592                                          * addition,) we'd rather restart the
 593                                          * loop just for safety.  Or does this
 594                                          * significantly reduce performance??
 595                                          */
 596                                         goto addrloop;
 597                                 }
 598                         }
 599                 } else {
 600                         /*
 601                          * A new RA might have made a deprecated address
 602                          * preferred.
 603                          */
 604                         ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
 605                 }
 606         }
 607
 608         /* expire prefix list */
 609         pr = nd_prefix.lh_first;
 610         while (pr) {
 611                 /*
 612                  * check prefix lifetime.
 613                  * since pltime is just for autoconf, pltime processing for
 614                  * prefix is not necessary.
 615                  */
 616                 if (pr->ndpr_expire && pr->ndpr_expire < time_second) {
 617                         struct nd_prefix *t;
 618                         t = pr->ndpr_next;
 619
 620                         /*
 621                          * address expiration and prefix expiration are
 622                          * separate.  NEVER perform in6_purgeaddr here.
 623                          */
 624
 625                         prelist_remove(pr);
 626                         pr = t;
 627                 } else
 628                         pr = pr->ndpr_next;
 629         }
 630         splx(s);
 631 }
 632
 633 static int
 634 regen_tmpaddr(ia6)
 635         struct in6_ifaddr *ia6; /* deprecated/invalidated temporary address */
 636 {
 637         struct ifaddr *ifa;
 638         struct ifnet *ifp;
 639         struct in6_ifaddr *public_ifa6 = NULL;
 640
 641         ifp = ia6->ia_ifa.ifa_ifp;
 642         for (ifa = ifp->if_addrlist.tqh_first; ifa;
 643              ifa = ifa->ifa_list.tqe_next) {
 644                 struct in6_ifaddr *it6;
 645
 646                 if (ifa->ifa_addr->sa_family != AF_INET6)
 647                         continue;
 648
 649                 it6 = (struct in6_ifaddr *)ifa;
 650
 651                 /* ignore no autoconf addresses. */
 652                 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0)
 653                         continue;
 654
 655                 /* ignore autoconf addresses with different prefixes. */
 656                 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
 657                         continue;
 658
 659                 /*
 660                  * Now we are looking at an autoconf address with the same
 661                  * prefix as ours.  If the address is temporary and is still
 662                  * preferred, do not create another one.  It would be rare, but
 663                  * could happen, for example, when we resume a laptop PC after
 664                  * a long period.
 665                  */
 666                 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
 667                     !IFA6_IS_DEPRECATED(it6)) {
 668                         public_ifa6 = NULL;
 669                         break;
 670                 }
 671
 672                 /*
 673                  * This is a public autoconf address that has the same prefix
 674                  * as ours.  If it is preferred, keep it.  We can't break the
 675                  * loop here, because there may be a still-preferred temporary
 676                  * address with the prefix.
 677                  */
 678                 if (!IFA6_IS_DEPRECATED(it6))
 679                     public_ifa6 = it6;
 680         }
 681
 682         if (public_ifa6 != NULL) {
 683                 int e;
 684
 685                 if ((e = in6_tmpifadd(public_ifa6, 0)) != 0) {
 686                         log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
 687                             " tmp addr,errno=%d\n", e);
 688                         return (-1);
 689                 }
 690                 return (0);
 691         }
 692
 693         return (-1);
 694 }
 695
 696 /*
 697  * Nuke neighbor cache/prefix/default router management table, right before
 698  * ifp goes away.
 699  */
 700 void
 701 nd6_purge(ifp)
 702         struct ifnet *ifp;
 703 {
 704         struct llinfo_nd6 *ln, *nln;
 705         struct nd_defrouter *dr, *ndr, drany;
 706         struct nd_prefix *pr, *npr;
 707
 708         /* Nuke default router list entries toward ifp */
 709         if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
 710                 /*
 711                  * The first entry of the list may be stored in
 712                  * the routing table, so we'll delete it later.
 713                  */
 714                 for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = ndr) {
 715                         ndr = TAILQ_NEXT(dr, dr_entry);
 716                         if (dr->ifp == ifp)
 717                                 defrtrlist_del(dr);
 718                 }
 719                 dr = TAILQ_FIRST(&nd_defrouter);
 720                 if (dr->ifp == ifp)
 721                         defrtrlist_del(dr);
 722         }
 723
 724         /* Nuke prefix list entries toward ifp */
 725         for (pr = nd_prefix.lh_first; pr; pr = npr) {
 726                 npr = pr->ndpr_next;
 727                 if (pr->ndpr_ifp == ifp) {
 728                         /*
 729                          * Previously, pr->ndpr_addr is removed as well,
 730                          * but I strongly believe we don't have to do it.
 731                          * nd6_purge() is only called from in6_ifdetach(),
 732                          * which removes all the associated interface addresses
 733                          * by itself.
 734                          * (jinmei@kame.net 20010129)
 735                          */
 736                         prelist_remove(pr);
 737                 }
 738         }
 739
 740         /* cancel default outgoing interface setting */
 741         if (nd6_defifindex == ifp->if_index)
 742                 nd6_setdefaultiface(0);
 743
 744         if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
 745                 /* refresh default router list */
 746                 bzero(&drany, sizeof(drany));
 747                 defrouter_delreq(&drany, 0);
 748                 defrouter_select();
 749         }
 750
 751         /*
 752          * Nuke neighbor cache entries for the ifp.
 753          * Note that rt->rt_ifp may not be the same as ifp,
 754          * due to KAME goto ours hack.  See RTM_RESOLVE case in
 755          * nd6_rtrequest(), and ip6_input().
 756          */
 757         ln = llinfo_nd6.ln_next;
 758         while (ln && ln != &llinfo_nd6) {
 759                 struct rtentry *rt;
 760                 struct sockaddr_dl *sdl;
 761
 762                 nln = ln->ln_next;
 763                 rt = ln->ln_rt;
 764                 if (rt && rt->rt_gateway &&
 765                     rt->rt_gateway->sa_family == AF_LINK) {
 766                         sdl = (struct sockaddr_dl *)rt->rt_gateway;
 767                         if (sdl->sdl_index == ifp->if_index)
 768                                 nln = nd6_free(rt);
 769                 }
 770                 ln = nln;
 771         }
 772 }
 773
 774 struct rtentry *
 775 nd6_lookup(addr6, create, ifp)
 776         struct in6_addr *addr6;
 777         int create;
 778         struct ifnet *ifp;
 779 {
 780         struct rtentry *rt;
 781         struct sockaddr_in6 sin6;
 782
 783         bzero(&sin6, sizeof(sin6));
 784         sin6.sin6_len = sizeof(struct sockaddr_in6);
 785         sin6.sin6_family = AF_INET6;
 786         sin6.sin6_addr = *addr6;
 787         rt = rtalloc1((struct sockaddr *)&sin6, create, 0UL);
 788         if (rt) {
 789                 if ((rt->rt_flags & RTF_LLINFO) == 0 && create) {
 790                         /*
 791                          * This is the case for the default route.
 792                          * If we want to create a neighbor cache for the
 793                          * address, we should free the route for the
 794                          * destination and allocate an interface route.
 795                          */
 796                         RTFREE_LOCKED(rt);
 797                         rt = 0;
 798                 }
 799         }
 800         if (!rt) {
 801                 if (create && ifp) {
 802                         int e;
 803
 804                         /*
 805                          * If no route is available and create is set,
 806                          * we allocate a host route for the destination
 807                          * and treat it like an interface route.
 808                          * This hack is necessary for a neighbor which can't
 809                          * be covered by our own prefix.
 810                          */
 811                         struct ifaddr *ifa =
 812                             ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp);
 813                         if (ifa == NULL)
 814                                 return (NULL);
 815
 816                         /*
 817                          * Create a new route.  RTF_LLINFO is necessary
 818                          * to create a Neighbor Cache entry for the
 819                          * destination in nd6_rtrequest which will be
 820                          * called in rtrequest via ifa->ifa_rtrequest.
 821                          */
 822                         if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6,
 823                             ifa->ifa_addr, (struct sockaddr *)&all1_sa,
 824                             (ifa->ifa_flags | RTF_HOST | RTF_LLINFO) &
 825                             ~RTF_CLONING, &rt)) != 0) {
 826                                 log(LOG_ERR,
 827                                     "nd6_lookup: failed to add route for a "
 828                                     "neighbor(%s), errno=%d\n",
 829                                     ip6_sprintf(addr6), e);
 830                         }
 831                         if (rt == NULL)
 832                                 return (NULL);
 833                         RT_LOCK(rt);
 834                         if (rt->rt_llinfo) {
 835                                 struct llinfo_nd6 *ln =
 836                                     (struct llinfo_nd6 *)rt->rt_llinfo;
 837                                 ln->ln_state = ND6_LLINFO_NOSTATE;
 838                         }
 839                 } else
 840                         return (NULL);
 841         }
 842         RT_LOCK_ASSERT(rt);
 843         RT_REMREF(rt);
 844         /*
 845          * Validation for the entry.
 846          * Note that the check for rt_llinfo is necessary because a cloned
 847          * route from a parent route that has the L flag (e.g. the default
 848          * route to a p2p interface) may have the flag, too, while the
 849          * destination is not actually a neighbor.
 850          * XXX: we can't use rt->rt_ifp to check for the interface, since
 851          *      it might be the loopback interface if the entry is for our
 852          *      own address on a non-loopback interface. Instead, we should
 853          *      use rt->rt_ifa->ifa_ifp, which would specify the REAL
 854          *      interface.
 855          */
 856         if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 ||
 857             rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL ||
 858             (ifp && rt->rt_ifa->ifa_ifp != ifp)) {
 859                 if (create) {
 860                         log(LOG_DEBUG,
 861                             "nd6_lookup: failed to lookup %s (if = %s)\n",
 862                             ip6_sprintf(addr6),
 863                             ifp ? if_name(ifp) : "unspec");
 864                         /* xxx more logs... kazu */
 865                 }
 866                 RT_UNLOCK(rt);
 867                 return (NULL);
 868         }
 869         RT_UNLOCK(rt);          /* XXX not ready to return rt locked */
 870         return (rt);
 871 }
 872
 873 /*
 874  * Test whether a given IPv6 address is a neighbor or not, ignoring
 875  * the actual neighbor cache.  The neighbor cache is ignored in order
 876  * to not reenter the routing code from within itself.
 877  */
 878 static int
 879 nd6_is_new_addr_neighbor(addr, ifp)
 880         struct sockaddr_in6 *addr;
 881         struct ifnet *ifp;
 882 {
 883         struct nd_prefix *pr;
 884
 885         /*
 886          * A link-local address is always a neighbor.
 887          * XXX: we should use the sin6_scope_id field rather than the embedded
 888          * interface index.
 889          * XXX: a link does not necessarily specify a single interface.
 890          */
 891         if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr) &&
 892             ntohs(*(u_int16_t *)&addr->sin6_addr.s6_addr[2]) == ifp->if_index)
 893                 return (1);
 894
 895         /*
 896          * If the address matches one of our addresses,
 897          * it should be a neighbor.
 898          * If the address matches one of our on-link prefixes, it should be a
 899          * neighbor.
 900          */
 901         for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
 902                 if (pr->ndpr_ifp != ifp)
 903                         continue;
 904
 905                 if (!(pr->ndpr_stateflags & NDPRF_ONLINK))
 906                         continue;
 907
 908                 if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
 909                     &addr->sin6_addr, &pr->ndpr_mask))
 910                         return (1);
 911         }
 912
 913         /*
 914          * If the default router list is empty, all addresses are regarded
 915          * as on-link, and thus, as a neighbor.
 916          * XXX: we restrict the condition to hosts, because routers usually do
 917          * not have the "default router list".
 918          */
 919         if (!ip6_forwarding && TAILQ_FIRST(&nd_defrouter) == NULL &&
 920             nd6_defifindex == ifp->if_index) {
 921                 return (1);
 922         }
 923
 924         return (0);
 925 }
 926
 927
 928 /*
 929  * Detect if a given IPv6 address identifies a neighbor on a given link.
 930  * XXX: should take care of the destination of a p2p link?
 931  */
 932 int
 933 nd6_is_addr_neighbor(addr, ifp)
 934         struct sockaddr_in6 *addr;
 935         struct ifnet *ifp;
 936 {
 937
 938         if (nd6_is_new_addr_neighbor(addr, ifp))
 939                 return (1);
 940
 941         /*
 942          * Even if the address matches none of our addresses, it might be
 943          * in the neighbor cache.
 944          */
 945         if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL)
 946                 return (1);
 947
 948         return (0);
 949 }
 950
 951 /*
 952  * Free an nd6 llinfo entry.
 953  */
 954 struct llinfo_nd6 *
 955 nd6_free(rt)
 956         struct rtentry *rt;
 957 {
 958         struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next;
 959         struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
 960         struct nd_defrouter *dr;
 961
 962         /*
 963          * we used to have pfctlinput(PRC_HOSTDEAD) here.
 964          * even though it is not harmful, it was not really necessary.
 965          */
 966
 967         if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
 968                 int s;
 969                 s = splnet();
 970                 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
 971                     rt->rt_ifp);
 972
 973                 if (ln->ln_router || dr) {
 974                         /*
 975                          * rt6_flush must be called whether or not the neighbor
 976                          * is in the Default Router List.
 977                          * See a corresponding comment in nd6_na_input().
 978                          */
 979                         rt6_flush(&in6, rt->rt_ifp);
 980                 }
 981
 982                 if (dr) {
 983                         /*
 984                          * Unreachablity of a router might affect the default
 985                          * router selection and on-link detection of advertised
 986                          * prefixes.
 987                          */
 988
 989                         /*
 990                          * Temporarily fake the state to choose a new default
 991                          * router and to perform on-link determination of
 992                          * prefixes correctly.
 993                          * Below the state will be set correctly,
 994                          * or the entry itself will be deleted.
 995                          */
 996                         ln->ln_state = ND6_LLINFO_INCOMPLETE;
 997
 998                         /*
 999                          * Since defrouter_select() does not affect the
1000                          * on-link determination and MIP6 needs the check
1001                          * before the default router selection, we perform
1002                          * the check now.
1003                          */
1004                         pfxlist_onlink_check();
1005
1006                         if (dr == TAILQ_FIRST(&nd_defrouter)) {
1007                                 /*
1008                                  * It is used as the current default router,
1009                                  * so we have to move it to the end of the
1010                                  * list and choose a new one.
1011                                  * XXX: it is not very efficient if this is
1012                                  *      the only router.
1013                                  */
1014                                 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
1015                                 TAILQ_INSERT_TAIL(&nd_defrouter, dr, dr_entry);
1016
1017                                 defrouter_select();
1018                         }
1019                 }
1020                 splx(s);
1021         }
1022
1023         /*
1024          * Before deleting the entry, remember the next entry as the
1025          * return value.  We need this because pfxlist_onlink_check() above
1026          * might have freed other entries (particularly the old next entry) as
1027          * a side effect (XXX).
1028          */
1029         next = ln->ln_next;
1030
1031         /*
1032          * Detach the route from the routing tree and the list of neighbor
1033          * caches, and disable the route entry not to be used in already
1034          * cached routes.
1035          */
1036         rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0,
1037             rt_mask(rt), 0, (struct rtentry **)0);
1038
1039         return (next);
1040 }
1041
1042 /*
1043  * Upper-layer reachability hint for Neighbor Unreachability Detection.
1044  *
1045  * XXX cost-effective metods?
1046  */
1047 void
1048 nd6_nud_hint(rt, dst6, force)
1049         struct rtentry *rt;
1050         struct in6_addr *dst6;
1051         int force;
1052 {
1053         struct llinfo_nd6 *ln;
1054
1055         /*
1056          * If the caller specified "rt", use that.  Otherwise, resolve the
1057          * routing table by supplied "dst6".
1058          */
1059         if (!rt) {
1060                 if (!dst6)
1061                         return;
1062                 if (!(rt = nd6_lookup(dst6, 0, NULL)))
1063                         return;
1064         }
1065
1066         if ((rt->rt_flags & RTF_GATEWAY) != 0 ||
1067             (rt->rt_flags & RTF_LLINFO) == 0 ||
1068             !rt->rt_llinfo || !rt->rt_gateway ||
1069             rt->rt_gateway->sa_family != AF_LINK) {
1070                 /* This is not a host route. */
1071                 return;
1072         }
1073
1074         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1075         if (ln->ln_state < ND6_LLINFO_REACHABLE)
1076                 return;
1077
1078         /*
1079          * if we get upper-layer reachability confirmation many times,
1080          * it is possible we have false information.
1081          */
1082         if (!force) {
1083                 ln->ln_byhint++;
1084                 if (ln->ln_byhint > nd6_maxnudhint)
1085                         return;
1086         }
1087
1088         ln->ln_state = ND6_LLINFO_REACHABLE;
1089         if (ln->ln_expire)
1090                 ln->ln_expire = time_second +
1091                         ND_IFINFO(rt->rt_ifp)->reachable;
1092 }
1093
1094 void
1095 nd6_rtrequest(req, rt, info)
1096         int     req;
1097         struct rtentry *rt;
1098         struct rt_addrinfo *info; /* xxx unused */
1099 {
1100         struct sockaddr *gate = rt->rt_gateway;
1101         struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1102         static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
1103         struct ifnet *ifp = rt->rt_ifp;
1104         struct ifaddr *ifa;
1105
1106         RT_LOCK_ASSERT(rt);
1107
1108         if ((rt->rt_flags & RTF_GATEWAY) != 0)
1109                 return;
1110
1111         if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) {
1112                 /*
1113                  * This is probably an interface direct route for a link
1114                  * which does not need neighbor caches (e.g. fe80::%lo0/64).
1115                  * We do not need special treatment below for such a route.
1116                  * Moreover, the RTF_LLINFO flag which would be set below
1117                  * would annoy the ndp(8) command.
1118                  */
1119                 return;
1120         }
1121
1122         if (req == RTM_RESOLVE &&
1123             (nd6_need_cache(ifp) == 0 || /* stf case */
1124              !nd6_is_new_addr_neighbor((struct sockaddr_in6 *)rt_key(rt),
1125              ifp))) {
1126                 /*
1127                  * FreeBSD and BSD/OS often make a cloned host route based
1128                  * on a less-specific route (e.g. the default route).
1129                  * If the less specific route does not have a "gateway"
1130                  * (this is the case when the route just goes to a p2p or an
1131                  * stf interface), we'll mistakenly make a neighbor cache for
1132                  * the host route, and will see strange neighbor solicitation
1133                  * for the corresponding destination.  In order to avoid the
1134                  * confusion, we check if the destination of the route is
1135                  * a neighbor in terms of neighbor discovery, and stop the
1136                  * process if not.  Additionally, we remove the LLINFO flag
1137                  * so that ndp(8) will not try to get the neighbor information
1138                  * of the destination.
1139                  */
1140                 rt->rt_flags &= ~RTF_LLINFO;
1141                 return;
1142         }
1143
1144         switch (req) {
1145         case RTM_ADD:
1146                 /*
1147                  * There is no backward compatibility :)
1148                  *
1149                  * if ((rt->rt_flags & RTF_HOST) == 0 &&
1150                  *     SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
1151                  *         rt->rt_flags |= RTF_CLONING;
1152                  */
1153                 if (rt->rt_flags & (RTF_CLONING | RTF_LLINFO)) {
1154                         /*
1155                          * Case 1: This route should come from
1156                          * a route to interface.  RTF_LLINFO flag is set
1157                          * for a host route whose destination should be
1158                          * treated as on-link.
1159                          */
1160                         rt_setgate(rt, rt_key(rt),
1161                                    (struct sockaddr *)&null_sdl);
1162                         gate = rt->rt_gateway;
1163                         SDL(gate)->sdl_type = ifp->if_type;
1164                         SDL(gate)->sdl_index = ifp->if_index;
1165                         if (ln)
1166                                 ln->ln_expire = time_second;
1167                         if (ln && ln->ln_expire == 0) {
1168                                 /* kludge for desktops */
1169                                 ln->ln_expire = 1;
1170                         }
1171                         if ((rt->rt_flags & RTF_CLONING) != 0)
1172                                 break;
1173                 }
1174                 /*
1175                  * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here.
1176                  * We don't do that here since llinfo is not ready yet.
1177                  *
1178                  * There are also couple of other things to be discussed:
1179                  * - unsolicited NA code needs improvement beforehand
1180                  * - RFC2461 says we MAY send multicast unsolicited NA
1181                  *   (7.2.6 paragraph 4), however, it also says that we
1182                  *   SHOULD provide a mechanism to prevent multicast NA storm.
1183                  *   we don't have anything like it right now.
1184                  *   note that the mechanism needs a mutual agreement
1185                  *   between proxies, which means that we need to implement
1186                  *   a new protocol, or a new kludge.
1187                  * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA.
1188                  *   we need to check ip6forwarding before sending it.
1189                  *   (or should we allow proxy ND configuration only for
1190                  *   routers?  there's no mention about proxy ND from hosts)
1191                  */
1192 #if 0
1193                 /* XXX it does not work */
1194                 if (rt->rt_flags & RTF_ANNOUNCE)
1195                         nd6_na_output(ifp,
1196                               &SIN6(rt_key(rt))->sin6_addr,
1197                               &SIN6(rt_key(rt))->sin6_addr,
1198                               ip6_forwarding ? ND_NA_FLAG_ROUTER : 0,
1199                               1, NULL);
1200 #endif
1201                 /* FALLTHROUGH */
1202         case RTM_RESOLVE:
1203                 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) {
1204                         /*
1205                          * Address resolution isn't necessary for a point to
1206                          * point link, so we can skip this test for a p2p link.
1207                          */
1208                         if (gate->sa_family != AF_LINK ||
1209                             gate->sa_len < sizeof(null_sdl)) {
1210                                 log(LOG_DEBUG,
1211                                     "nd6_rtrequest: bad gateway value: %s\n",
1212                                     if_name(ifp));
1213                                 break;
1214                         }
1215                         SDL(gate)->sdl_type = ifp->if_type;
1216                         SDL(gate)->sdl_index = ifp->if_index;
1217                 }
1218                 if (ln != NULL)
1219                         break;  /* This happens on a route change */
1220                 /*
1221                  * Case 2: This route may come from cloning, or a manual route
1222                  * add with a LL address.
1223                  */
1224                 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln));
1225                 rt->rt_llinfo = (caddr_t)ln;
1226                 if (!ln) {
1227                         log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n");
1228                         break;
1229                 }
1230                 nd6_inuse++;
1231                 nd6_allocated++;
1232                 bzero(ln, sizeof(*ln));
1233                 ln->ln_rt = rt;
1234                 /* this is required for "ndp" command. - shin */
1235                 if (req == RTM_ADD) {
1236                         /*
1237                          * gate should have some valid AF_LINK entry,
1238                          * and ln->ln_expire should have some lifetime
1239                          * which is specified by ndp command.
1240                          */
1241                         ln->ln_state = ND6_LLINFO_REACHABLE;
1242                         ln->ln_byhint = 0;
1243                 } else {
1244                         /*
1245                          * When req == RTM_RESOLVE, rt is created and
1246                          * initialized in rtrequest(), so rt_expire is 0.
1247                          */
1248                         ln->ln_state = ND6_LLINFO_NOSTATE;
1249                         ln->ln_expire = time_second;
1250                 }
1251                 rt->rt_flags |= RTF_LLINFO;
1252                 ln->ln_next = llinfo_nd6.ln_next;
1253                 llinfo_nd6.ln_next = ln;
1254                 ln->ln_prev = &llinfo_nd6;
1255                 ln->ln_next->ln_prev = ln;
1256
1257                 /*
1258                  * check if rt_key(rt) is one of my address assigned
1259                  * to the interface.
1260                  */
1261                 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp,
1262                     &SIN6(rt_key(rt))->sin6_addr);
1263                 if (ifa) {
1264                         caddr_t macp = nd6_ifptomac(ifp);
1265                         ln->ln_expire = 0;
1266                         ln->ln_state = ND6_LLINFO_REACHABLE;
1267                         ln->ln_byhint = 0;
1268                         if (macp) {
1269                                 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen);
1270                                 SDL(gate)->sdl_alen = ifp->if_addrlen;
1271                         }
1272                         if (nd6_useloopback) {
1273                                 rt->rt_ifp = &loif[0];  /* XXX */
1274                                 /*
1275                                  * Make sure rt_ifa be equal to the ifaddr
1276                                  * corresponding to the address.
1277                                  * We need this because when we refer
1278                                  * rt_ifa->ia6_flags in ip6_input, we assume
1279                                  * that the rt_ifa points to the address instead
1280                                  * of the loopback address.
1281                                  */
1282                                 if (ifa != rt->rt_ifa) {
1283                                         IFAFREE(rt->rt_ifa);
1284                                         IFAREF(ifa);
1285                                         rt->rt_ifa = ifa;
1286                                 }
1287                         }
1288                 } else if (rt->rt_flags & RTF_ANNOUNCE) {
1289                         ln->ln_expire = 0;
1290                         ln->ln_state = ND6_LLINFO_REACHABLE;
1291                         ln->ln_byhint = 0;
1292
1293                         /* join solicited node multicast for proxy ND */
1294                         if (ifp->if_flags & IFF_MULTICAST) {
1295                                 struct in6_addr llsol;
1296                                 int error;
1297
1298                                 llsol = SIN6(rt_key(rt))->sin6_addr;
1299                                 llsol.s6_addr16[0] = htons(0xff02);
1300                                 llsol.s6_addr16[1] = htons(ifp->if_index);
1301                                 llsol.s6_addr32[1] = 0;
1302                                 llsol.s6_addr32[2] = htonl(1);
1303                                 llsol.s6_addr8[12] = 0xff;
1304
1305                                 if (!in6_addmulti(&llsol, ifp, &error)) {
1306                                         nd6log((LOG_ERR, "%s: failed to join "
1307                                             "%s (errno=%d)\n", if_name(ifp),
1308                                             ip6_sprintf(&llsol), error));
1309                                 }
1310                         }
1311                 }
1312                 break;
1313
1314         case RTM_DELETE:
1315                 if (!ln)
1316                         break;
1317                 /* leave from solicited node multicast for proxy ND */
1318                 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 &&
1319                     (ifp->if_flags & IFF_MULTICAST) != 0) {
1320                         struct in6_addr llsol;
1321                         struct in6_multi *in6m;
1322
1323                         llsol = SIN6(rt_key(rt))->sin6_addr;
1324                         llsol.s6_addr16[0] = htons(0xff02);
1325                         llsol.s6_addr16[1] = htons(ifp->if_index);
1326                         llsol.s6_addr32[1] = 0;
1327                         llsol.s6_addr32[2] = htonl(1);
1328                         llsol.s6_addr8[12] = 0xff;
1329
1330                         IN6_LOOKUP_MULTI(llsol, ifp, in6m);
1331                         if (in6m)
1332                                 in6_delmulti(in6m);
1333                 }
1334                 nd6_inuse--;
1335                 ln->ln_next->ln_prev = ln->ln_prev;
1336                 ln->ln_prev->ln_next = ln->ln_next;
1337                 ln->ln_prev = NULL;
1338                 rt->rt_llinfo = 0;
1339                 rt->rt_flags &= ~RTF_LLINFO;
1340                 if (ln->ln_hold)
1341                         m_freem(ln->ln_hold);
1342                 Free((caddr_t)ln);
1343         }
1344 }
1345
1346 int
1347 nd6_ioctl(cmd, data, ifp)
1348         u_long cmd;
1349         caddr_t data;
1350         struct ifnet *ifp;
1351 {
1352         struct in6_drlist *drl = (struct in6_drlist *)data;
1353         struct in6_oprlist *oprl = (struct in6_oprlist *)data;
1354         struct in6_ndireq *ndi = (struct in6_ndireq *)data;
1355         struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
1356         struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
1357         struct nd_defrouter *dr, any;
1358         struct nd_prefix *pr;
1359         struct rtentry *rt;
1360         int i = 0, error = 0;
1361         int s;
1362
1363         switch (cmd) {
1364         case SIOCGDRLST_IN6:
1365                 /*
1366                  * obsolete API, use sysctl under net.inet6.icmp6
1367                  */
1368                 bzero(drl, sizeof(*drl));
1369                 s = splnet();
1370                 dr = TAILQ_FIRST(&nd_defrouter);
1371                 while (dr && i < DRLSTSIZ) {
1372                         drl->defrouter[i].rtaddr = dr->rtaddr;
1373                         in6_clearscope(&drl->defrouter[i].rtaddr);
1374
1375                         drl->defrouter[i].flags = dr->flags;
1376                         drl->defrouter[i].rtlifetime = dr->rtlifetime;
1377                         drl->defrouter[i].expire = dr->expire;
1378                         drl->defrouter[i].if_index = dr->ifp->if_index;
1379                         i++;
1380                         dr = TAILQ_NEXT(dr, dr_entry);
1381                 }
1382                 splx(s);
1383                 break;
1384         case SIOCGPRLST_IN6:
1385                 /*
1386                  * obsolete API, use sysctl under net.inet6.icmp6
1387                  *
1388                  * XXX the structure in6_prlist was changed in backward-
1389                  * incompatible manner.  in6_oprlist is used for SIOCGPRLST_IN6,
1390                  * in6_prlist is used for nd6_sysctl() - fill_prlist().
1391                  */
1392                 /*
1393                  * XXX meaning of fields, especialy "raflags", is very
1394                  * differnet between RA prefix list and RR/static prefix list.
1395                  * how about separating ioctls into two?
1396                  */
1397                 bzero(oprl, sizeof(*oprl));
1398                 s = splnet();
1399                 pr = nd_prefix.lh_first;
1400                 while (pr && i < PRLSTSIZ) {
1401                         struct nd_pfxrouter *pfr;
1402                         int j;
1403
1404                         (void)in6_embedscope(&oprl->prefix[i].prefix,
1405                             &pr->ndpr_prefix, NULL, NULL);
1406                         oprl->prefix[i].raflags = pr->ndpr_raf;
1407                         oprl->prefix[i].prefixlen = pr->ndpr_plen;
1408                         oprl->prefix[i].vltime = pr->ndpr_vltime;
1409                         oprl->prefix[i].pltime = pr->ndpr_pltime;
1410                         oprl->prefix[i].if_index = pr->ndpr_ifp->if_index;
1411                         oprl->prefix[i].expire = pr->ndpr_expire;
1412
1413                         pfr = pr->ndpr_advrtrs.lh_first;
1414                         j = 0;
1415                         while (pfr) {
1416                                 if (j < DRLSTSIZ) {
1417 #define RTRADDR oprl->prefix[i].advrtr[j]
1418                                         RTRADDR = pfr->router->rtaddr;
1419                                         in6_clearscope(&RTRADDR);
1420 #undef RTRADDR
1421                                 }
1422                                 j++;
1423                                 pfr = pfr->pfr_next;
1424                         }
1425                         oprl->prefix[i].advrtrs = j;
1426                         oprl->prefix[i].origin = PR_ORIG_RA;
1427
1428                         i++;
1429                         pr = pr->ndpr_next;
1430                 }
1431                 splx(s);
1432
1433                 break;
1434         case OSIOCGIFINFO_IN6:
1435                 /* XXX: old ndp(8) assumes a positive value for linkmtu. */
1436                 bzero(&ndi->ndi, sizeof(ndi->ndi));
1437                 ndi->ndi.linkmtu = IN6_LINKMTU(ifp);
1438                 ndi->ndi.maxmtu = ND_IFINFO(ifp)->maxmtu;
1439                 ndi->ndi.basereachable = ND_IFINFO(ifp)->basereachable;
1440                 ndi->ndi.reachable = ND_IFINFO(ifp)->reachable;
1441                 ndi->ndi.retrans = ND_IFINFO(ifp)->retrans;
1442                 ndi->ndi.flags = ND_IFINFO(ifp)->flags;
1443                 ndi->ndi.recalctm = ND_IFINFO(ifp)->recalctm;
1444                 ndi->ndi.chlim = ND_IFINFO(ifp)->chlim;
1445                 break;
1446         case SIOCGIFINFO_IN6:
1447                 ndi->ndi = *ND_IFINFO(ifp);
1448                 ndi->ndi.linkmtu = IN6_LINKMTU(ifp);
1449                 break;
1450         case SIOCSIFINFO_FLAGS:
1451                 ND_IFINFO(ifp)->flags = ndi->ndi.flags;
1452                 break;
1453         case SIOCSNDFLUSH_IN6:  /* XXX: the ioctl name is confusing... */
1454                 /* flush default router list */
1455                 /*
1456                  * xxx sumikawa: should not delete route if default
1457                  * route equals to the top of default router list
1458                  */
1459                 bzero(&any, sizeof(any));
1460                 defrouter_delreq(&any, 0);
1461                 defrouter_select();
1462                 /* xxx sumikawa: flush prefix list */
1463                 break;
1464         case SIOCSPFXFLUSH_IN6:
1465         {
1466                 /* flush all the prefix advertised by routers */
1467                 struct nd_prefix *pr, *next;
1468
1469                 s = splnet();
1470                 for (pr = nd_prefix.lh_first; pr; pr = next) {
1471                         struct in6_ifaddr *ia, *ia_next;
1472
1473                         next = pr->ndpr_next;
1474
1475                         if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1476                                 continue; /* XXX */
1477
1478                         /* do we really have to remove addresses as well? */
1479                         for (ia = in6_ifaddr; ia; ia = ia_next) {
1480                                 /* ia might be removed.  keep the next ptr. */
1481                                 ia_next = ia->ia_next;
1482
1483                                 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0)
1484                                         continue;
1485
1486                                 if (ia->ia6_ndpr == pr)
1487                                         in6_purgeaddr(&ia->ia_ifa);
1488                         }
1489                         prelist_remove(pr);
1490                 }
1491                 splx(s);
1492                 break;
1493         }
1494         case SIOCSRTRFLUSH_IN6:
1495         {
1496                 /* flush all the default routers */
1497                 struct nd_defrouter *dr, *next;
1498
1499                 s = splnet();
1500                 if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
1501                         /*
1502                          * The first entry of the list may be stored in
1503                          * the routing table, so we'll delete it later.
1504                          */
1505                         for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = next) {
1506                                 next = TAILQ_NEXT(dr, dr_entry);
1507                                 defrtrlist_del(dr);
1508                         }
1509                         defrtrlist_del(TAILQ_FIRST(&nd_defrouter));
1510                 }
1511                 splx(s);
1512                 break;
1513         }
1514         case SIOCGNBRINFO_IN6:
1515         {
1516                 struct llinfo_nd6 *ln;
1517                 struct in6_addr nb_addr = nbi->addr; /* make local for safety */
1518
1519                 /*
1520                  * XXX: KAME specific hack for scoped addresses
1521                  *      XXXX: for other scopes than link-local?
1522                  */
1523                 if (IN6_IS_ADDR_LINKLOCAL(&nbi->addr) ||
1524                     IN6_IS_ADDR_MC_LINKLOCAL(&nbi->addr)) {
1525                         u_int16_t *idp = (u_int16_t *)&nb_addr.s6_addr[2];
1526
1527                         if (*idp == 0)
1528                                 *idp = htons(ifp->if_index);
1529                 }
1530
1531                 s = splnet();
1532                 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL) {
1533                         error = EINVAL;
1534                         splx(s);
1535                         break;
1536                 }
1537                 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1538                 nbi->state = ln->ln_state;
1539                 nbi->asked = ln->ln_asked;
1540                 nbi->isrouter = ln->ln_router;
1541                 nbi->expire = ln->ln_expire;
1542                 splx(s);
1543
1544                 break;
1545         }
1546         case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1547                 ndif->ifindex = nd6_defifindex;
1548                 break;
1549         case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1550                 return (nd6_setdefaultiface(ndif->ifindex));
1551         }
1552         return (error);
1553 }
1554
1555 /*
1556  * Create neighbor cache entry and cache link-layer address,
1557  * on reception of inbound ND6 packets.  (RS/RA/NS/redirect)
1558  */
1559 struct rtentry *
1560 nd6_cache_lladdr(ifp, from, lladdr, lladdrlen, type, code)
1561         struct ifnet *ifp;
1562         struct in6_addr *from;
1563         char *lladdr;
1564         int lladdrlen;
1565         int type;       /* ICMP6 type */
1566         int code;       /* type dependent information */
1567 {
1568         struct rtentry *rt = NULL;
1569         struct llinfo_nd6 *ln = NULL;
1570         int is_newentry;
1571         struct sockaddr_dl *sdl = NULL;
1572         int do_update;
1573         int olladdr;
1574         int llchange;
1575         int newstate = 0;
1576
1577         if (!ifp)
1578                 panic("ifp == NULL in nd6_cache_lladdr");
1579         if (!from)
1580                 panic("from == NULL in nd6_cache_lladdr");
1581
1582         /* nothing must be updated for unspecified address */
1583         if (IN6_IS_ADDR_UNSPECIFIED(from))
1584                 return NULL;
1585
1586         /*
1587          * Validation about ifp->if_addrlen and lladdrlen must be done in
1588          * the caller.
1589          *
1590          * XXX If the link does not have link-layer adderss, what should
1591          * we do? (ifp->if_addrlen == 0)
1592          * Spec says nothing in sections for RA, RS and NA.  There's small
1593          * description on it in NS section (RFC 2461 7.2.3).
1594          */
1595
1596         rt = nd6_lookup(from, 0, ifp);
1597         if (!rt) {
1598 #if 0
1599                 /* nothing must be done if there's no lladdr */
1600                 if (!lladdr || !lladdrlen)
1601                         return NULL;
1602 #endif
1603
1604                 rt = nd6_lookup(from, 1, ifp);
1605                 is_newentry = 1;
1606         } else {
1607                 /* do nothing if static ndp is set */
1608                 if (rt->rt_flags & RTF_STATIC)
1609                         return NULL;
1610                 is_newentry = 0;
1611         }
1612
1613         if (!rt)
1614                 return NULL;
1615         if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) {
1616 fail:
1617                 (void)nd6_free(rt);
1618                 return NULL;
1619         }
1620         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1621         if (!ln)
1622                 goto fail;
1623         if (!rt->rt_gateway)
1624                 goto fail;
1625         if (rt->rt_gateway->sa_family != AF_LINK)
1626                 goto fail;
1627         sdl = SDL(rt->rt_gateway);
1628
1629         olladdr = (sdl->sdl_alen) ? 1 : 0;
1630         if (olladdr && lladdr) {
1631                 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
1632                         llchange = 1;
1633                 else
1634                         llchange = 0;
1635         } else
1636                 llchange = 0;
1637
1638         /*
1639          * newentry olladdr  lladdr  llchange   (*=record)
1640          *      0       n       n       --      (1)
1641          *      0       y       n       --      (2)
1642          *      0       n       y       --      (3) * STALE
1643          *      0       y       y       n       (4) *
1644          *      0       y       y       y       (5) * STALE
1645          *      1       --      n       --      (6)   NOSTATE(= PASSIVE)
1646          *      1       --      y       --      (7) * STALE
1647          */
1648
1649         if (lladdr) {           /* (3-5) and (7) */
1650                 /*
1651                  * Record source link-layer address
1652                  * XXX is it dependent to ifp->if_type?
1653                  */
1654                 sdl->sdl_alen = ifp->if_addrlen;
1655                 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
1656         }
1657
1658         if (!is_newentry) {
1659                 if ((!olladdr && lladdr) ||             /* (3) */
1660                     (olladdr && lladdr && llchange)) {  /* (5) */
1661                         do_update = 1;
1662                         newstate = ND6_LLINFO_STALE;
1663                 } else                                  /* (1-2,4) */
1664                         do_update = 0;
1665         } else {
1666                 do_update = 1;
1667                 if (!lladdr)                            /* (6) */
1668                         newstate = ND6_LLINFO_NOSTATE;
1669                 else                                    /* (7) */
1670                         newstate = ND6_LLINFO_STALE;
1671         }
1672
1673         if (do_update) {
1674                 /*
1675                  * Update the state of the neighbor cache.
1676                  */
1677                 ln->ln_state = newstate;
1678
1679                 if (ln->ln_state == ND6_LLINFO_STALE) {
1680                         /*
1681                          * XXX: since nd6_output() below will cause
1682                          * state tansition to DELAY and reset the timer,
1683                          * we must set the timer now, although it is actually
1684                          * meaningless.
1685                          */
1686                         ln->ln_expire = time_second + nd6_gctimer;
1687
1688                         if (ln->ln_hold) {
1689                                 /*
1690                                  * we assume ifp is not a p2p here, so just
1691                                  * set the 2nd argument as the 1st one.
1692                                  */
1693                                 nd6_output(ifp, ifp, ln->ln_hold,
1694                                     (struct sockaddr_in6 *)rt_key(rt), rt);
1695                                 ln->ln_hold = NULL;
1696                         }
1697                 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
1698                         /* probe right away */
1699                         ln->ln_expire = time_second;
1700                 }
1701         }
1702
1703         /*
1704          * ICMP6 type dependent behavior.
1705          *
1706          * NS: clear IsRouter if new entry
1707          * RS: clear IsRouter
1708          * RA: set IsRouter if there's lladdr
1709          * redir: clear IsRouter if new entry
1710          *
1711          * RA case, (1):
1712          * The spec says that we must set IsRouter in the following cases:
1713          * - If lladdr exist, set IsRouter.  This means (1-5).
1714          * - If it is old entry (!newentry), set IsRouter.  This means (7).
1715          * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1716          * A quetion arises for (1) case.  (1) case has no lladdr in the
1717          * neighbor cache, this is similar to (6).
1718          * This case is rare but we figured that we MUST NOT set IsRouter.
1719          *
1720          * newentry olladdr  lladdr  llchange       NS  RS  RA  redir
1721          *                                                      D R
1722          *      0       n       n       --      (1)     c   ?     s
1723          *      0       y       n       --      (2)     c   s     s
1724          *      0       n       y       --      (3)     c   s     s
1725          *      0       y       y       n       (4)     c   s     s
1726          *      0       y       y       y       (5)     c   s     s
1727          *      1       --      n       --      (6) c   c       c s
1728          *      1       --      y       --      (7) c   c   s   c s
1729          *
1730          *                                      (c=clear s=set)
1731          */
1732         switch (type & 0xff) {
1733         case ND_NEIGHBOR_SOLICIT:
1734                 /*
1735                  * New entry must have is_router flag cleared.
1736                  */
1737                 if (is_newentry)        /* (6-7) */
1738                         ln->ln_router = 0;
1739                 break;
1740         case ND_REDIRECT:
1741                 /*
1742                  * If the icmp is a redirect to a better router, always set the
1743                  * is_router flag.  Otherwise, if the entry is newly created,
1744                  * clear the flag.  [RFC 2461, sec 8.3]
1745                  */
1746                 if (code == ND_REDIRECT_ROUTER)
1747                         ln->ln_router = 1;
1748                 else if (is_newentry) /* (6-7) */
1749                         ln->ln_router = 0;
1750                 break;
1751         case ND_ROUTER_SOLICIT:
1752                 /*
1753                  * is_router flag must always be cleared.
1754                  */
1755                 ln->ln_router = 0;
1756                 break;
1757         case ND_ROUTER_ADVERT:
1758                 /*
1759                  * Mark an entry with lladdr as a router.
1760                  */
1761                 if ((!is_newentry && (olladdr || lladdr)) ||    /* (2-5) */
1762                     (is_newentry && lladdr)) {                  /* (7) */
1763                         ln->ln_router = 1;
1764                 }
1765                 break;
1766         }
1767
1768         /*
1769          * When the link-layer address of a router changes, select the
1770          * best router again.  In particular, when the neighbor entry is newly
1771          * created, it might affect the selection policy.
1772          * Question: can we restrict the first condition to the "is_newentry"
1773          * case?
1774          * XXX: when we hear an RA from a new router with the link-layer
1775          * address option, defrouter_select() is called twice, since
1776          * defrtrlist_update called the function as well.  However, I believe
1777          * we can compromise the overhead, since it only happens the first
1778          * time.
1779          * XXX: although defrouter_select() should not have a bad effect
1780          * for those are not autoconfigured hosts, we explicitly avoid such
1781          * cases for safety.
1782          */
1783         if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv)
1784                 defrouter_select();
1785
1786         return rt;
1787 }
1788
1789 static void
1790 nd6_slowtimo(ignored_arg)
1791     void *ignored_arg;
1792 {
1793         int s = splnet();
1794         struct nd_ifinfo *nd6if;
1795         struct ifnet *ifp;
1796
1797         callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
1798             nd6_slowtimo, NULL);
1799         IFNET_RLOCK();
1800         for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1801                 nd6if = ND_IFINFO(ifp);
1802                 if (nd6if->basereachable && /* already initialized */
1803                     (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
1804                         /*
1805                          * Since reachable time rarely changes by router
1806                          * advertisements, we SHOULD insure that a new random
1807                          * value gets recomputed at least once every few hours.
1808                          * (RFC 2461, 6.3.4)
1809                          */
1810                         nd6if->recalctm = nd6_recalc_reachtm_interval;
1811                         nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
1812                 }
1813         }
1814         IFNET_RUNLOCK();
1815         splx(s);
1816 }
1817
1818 #define senderr(e) { error = (e); goto bad;}
1819 int
1820 nd6_output(ifp, origifp, m0, dst, rt0)
1821         struct ifnet *ifp;
1822         struct ifnet *origifp;
1823         struct mbuf *m0;
1824         struct sockaddr_in6 *dst;
1825         struct rtentry *rt0;
1826 {
1827         struct mbuf *m = m0;
1828         struct rtentry *rt = rt0;
1829         struct sockaddr_in6 *gw6 = NULL;
1830         struct llinfo_nd6 *ln = NULL;
1831         int error = 0;
1832
1833         if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1834                 goto sendpkt;
1835
1836         if (nd6_need_cache(ifp) == 0)
1837                 goto sendpkt;
1838
1839         /*
1840          * next hop determination.  This routine is derived from ether_outpout.
1841          */
1842 again:
1843         if (rt) {
1844                 if ((rt->rt_flags & RTF_UP) == 0) {
1845                         rt0 = rt = rtalloc1((struct sockaddr *)dst, 1, 0UL);
1846                         if (rt != NULL) {
1847                                 RT_REMREF(rt);
1848                                 RT_UNLOCK(rt);
1849                                 if (rt->rt_ifp != ifp)
1850                                         /*
1851                                          * XXX maybe we should update ifp too,
1852                                          * but the original code didn't and I
1853                                          * don't know what is correct here.
1854                                          */
1855                                         goto again;
1856                         } else
1857                                 senderr(EHOSTUNREACH);
1858                 }
1859
1860                 if (rt->rt_flags & RTF_GATEWAY) {
1861                         gw6 = (struct sockaddr_in6 *)rt->rt_gateway;
1862
1863                         /*
1864                          * We skip link-layer address resolution and NUD
1865                          * if the gateway is not a neighbor from ND point
1866                          * of view, regardless of the value of nd_ifinfo.flags.
1867                          * The second condition is a bit tricky; we skip
1868                          * if the gateway is our own address, which is
1869                          * sometimes used to install a route to a p2p link.
1870                          */
1871                         if (!nd6_is_addr_neighbor(gw6, ifp) ||
1872                             in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) {
1873                                 /*
1874                                  * We allow this kind of tricky route only
1875                                  * when the outgoing interface is p2p.
1876                                  * XXX: we may need a more generic rule here.
1877                                  */
1878                                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
1879                                         senderr(EHOSTUNREACH);
1880
1881                                 goto sendpkt;
1882                         }
1883
1884                         if (rt->rt_gwroute == 0)
1885                                 goto lookup;
1886                         if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
1887                                 RT_LOCK(rt);
1888                                 rtfree(rt); rt = rt0;
1889                         lookup:
1890                                 rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1, 0UL);
1891                                 if ((rt = rt->rt_gwroute) == 0)
1892                                         senderr(EHOSTUNREACH);
1893                                 RT_UNLOCK(rt);
1894                         }
1895                 }
1896         }
1897
1898         /*
1899          * Address resolution or Neighbor Unreachability Detection
1900          * for the next hop.
1901          * At this point, the destination of the packet must be a unicast
1902          * or an anycast address(i.e. not a multicast).
1903          */
1904
1905         /* Look up the neighbor cache for the nexthop */
1906         if (rt && (rt->rt_flags & RTF_LLINFO) != 0)
1907                 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1908         else {
1909                 /*
1910                  * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
1911                  * the condition below is not very efficient.  But we believe
1912                  * it is tolerable, because this should be a rare case.
1913                  */
1914                 if (nd6_is_addr_neighbor(dst, ifp) &&
1915                     (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL)
1916                         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1917         }
1918         if (!ln || !rt) {
1919                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 &&
1920                     !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) {
1921                         log(LOG_DEBUG,
1922                             "nd6_output: can't allocate llinfo for %s "
1923                             "(ln=%p, rt=%p)\n",
1924                             ip6_sprintf(&dst->sin6_addr), ln, rt);
1925                         senderr(EIO);   /* XXX: good error? */
1926                 }
1927
1928                 goto sendpkt;   /* send anyway */
1929         }
1930
1931         /* We don't have to do link-layer address resolution on a p2p link. */
1932         if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
1933             ln->ln_state < ND6_LLINFO_REACHABLE) {
1934                 ln->ln_state = ND6_LLINFO_STALE;
1935                 ln->ln_expire = time_second + nd6_gctimer;
1936         }
1937
1938         /*
1939          * The first time we send a packet to a neighbor whose entry is
1940          * STALE, we have to change the state to DELAY and a sets a timer to
1941          * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
1942          * neighbor unreachability detection on expiration.
1943          * (RFC 2461 7.3.3)
1944          */
1945         if (ln->ln_state == ND6_LLINFO_STALE) {
1946                 ln->ln_asked = 0;
1947                 ln->ln_state = ND6_LLINFO_DELAY;
1948                 ln->ln_expire = time_second + nd6_delay;
1949         }
1950
1951         /*
1952          * If the neighbor cache entry has a state other than INCOMPLETE
1953          * (i.e. its link-layer address is already resolved), just
1954          * send the packet.
1955          */
1956         if (ln->ln_state > ND6_LLINFO_INCOMPLETE)
1957                 goto sendpkt;
1958
1959         /*
1960          * There is a neighbor cache entry, but no ethernet address
1961          * response yet.  Replace the held mbuf (if any) with this
1962          * latest one.
1963          *
1964          * This code conforms to the rate-limiting rule described in Section
1965          * 7.2.2 of RFC 2461, because the timer is set correctly after sending
1966          * an NS below.
1967          */
1968         if (ln->ln_state == ND6_LLINFO_NOSTATE)
1969                 ln->ln_state = ND6_LLINFO_INCOMPLETE;
1970         if (ln->ln_hold)
1971                 m_freem(ln->ln_hold);
1972         ln->ln_hold = m;
1973         if (ln->ln_expire) {
1974                 if (ln->ln_asked < nd6_mmaxtries &&
1975                     ln->ln_expire < time_second) {
1976                         ln->ln_asked++;
1977                         ln->ln_expire = time_second +
1978                                 ND_IFINFO(ifp)->retrans / 1000;
1979                         nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0);
1980                 }
1981         }
1982         return (0);
1983
1984   sendpkt:
1985 #ifdef IPSEC
1986         /* clean ipsec history once it goes out of the node */
1987         ipsec_delaux(m);
1988 #endif
1989
1990 #ifdef MAC
1991         mac_create_mbuf_linklayer(ifp, m);
1992 #endif
1993         if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
1994                 return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst,
1995                     rt));
1996         }
1997         return ((*ifp->if_output)(ifp, m, (struct sockaddr *)dst, rt));
1998
1999   bad:
2000         if (m)
2001                 m_freem(m);
2002         return (error);
2003 }
2004 #undef senderr
2005
2006 int
2007 nd6_need_cache(ifp)
2008         struct ifnet *ifp;
2009 {
2010         /*
2011          * XXX: we currently do not make neighbor cache on any interface
2012          * other than ARCnet, Ethernet, FDDI and GIF.
2013          *
2014          * RFC2893 says:
2015          * - unidirectional tunnels needs no ND
2016          */
2017         switch (ifp->if_type) {
2018         case IFT_ARCNET:
2019         case IFT_ETHER:
2020         case IFT_FDDI:
2021         case IFT_IEEE1394:
2022 #ifdef IFT_L2VLAN
2023         case IFT_L2VLAN:
2024 #endif
2025 #ifdef IFT_IEEE80211
2026         case IFT_IEEE80211:
2027 #endif
2028 #ifdef IFT_CARP
2029         case IFT_CARP:
2030 #endif
2031         case IFT_GIF:           /* XXX need more cases? */
2032                 return (1);
2033         default:
2034                 return (0);
2035         }
2036 }
2037
2038 int
2039 nd6_storelladdr(ifp, rt0, m, dst, desten)
2040         struct ifnet *ifp;
2041         struct rtentry *rt0;
2042         struct mbuf *m;
2043         struct sockaddr *dst;
2044         u_char *desten;
2045 {
2046         int i;
2047         struct sockaddr_dl *sdl;
2048         struct rtentry *rt;
2049
2050         if (m->m_flags & M_MCAST) {
2051                 switch (ifp->if_type) {
2052                 case IFT_ETHER:
2053                 case IFT_FDDI:
2054 #ifdef IFT_L2VLAN
2055                 case IFT_L2VLAN:
2056 #endif
2057 #ifdef IFT_IEEE80211
2058                 case IFT_IEEE80211:
2059 #endif
2060                 case IFT_ISO88025:
2061                         ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr,
2062                                                  desten);
2063                         return (0);
2064                 case IFT_IEEE1394:
2065                         /*
2066                          * netbsd can use if_broadcastaddr, but we don't do so
2067                          * to reduce # of ifdef.
2068                          */
2069                         for (i = 0; i < ifp->if_addrlen; i++)
2070                                 desten[i] = ~0;
2071                         return (0);
2072                 case IFT_ARCNET:
2073                         *desten = 0;
2074                         return (0);
2075                 default:
2076                         m_freem(m);
2077                         return (EAFNOSUPPORT);
2078                 }
2079         }
2080
2081         i = rt_check(&rt, &rt0, dst);
2082         if (i) {
2083                 m_freem(m);
2084                 return i;
2085         }
2086
2087         if (rt == NULL) {
2088                 /* this could happen, if we could not allocate memory */
2089                 m_freem(m);
2090                 return (ENOMEM);
2091         }
2092         if (rt->rt_gateway->sa_family != AF_LINK) {
2093                 printf("nd6_storelladdr: something odd happens\n");
2094                 m_freem(m);
2095                 return (EINVAL);
2096         }
2097         sdl = SDL(rt->rt_gateway);
2098         if (sdl->sdl_alen == 0) {
2099                 /* this should be impossible, but we bark here for debugging */
2100                 printf("nd6_storelladdr: sdl_alen == 0\n");
2101                 m_freem(m);
2102                 return (EINVAL);
2103         }
2104
2105         bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
2106         return (0);
2107 }
2108
2109 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
2110 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
2111 #ifdef SYSCTL_DECL
2112 SYSCTL_DECL(_net_inet6_icmp6);
2113 #endif
2114 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2115         CTLFLAG_RD, nd6_sysctl_drlist, "");
2116 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
2117         CTLFLAG_RD, nd6_sysctl_prlist, "");
2118
2119 static int
2120 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2121 {
2122         int error;
2123         char buf[1024];
2124         struct in6_defrouter *d, *de;
2125         struct nd_defrouter *dr;
2126
2127         if (req->newptr)
2128                 return EPERM;
2129         error = 0;
2130
2131         for (dr = TAILQ_FIRST(&nd_defrouter); dr;
2132              dr = TAILQ_NEXT(dr, dr_entry)) {
2133                 d = (struct in6_defrouter *)buf;
2134                 de = (struct in6_defrouter *)(buf + sizeof(buf));
2135
2136                 if (d + 1 <= de) {
2137                         bzero(d, sizeof(*d));
2138                         d->rtaddr.sin6_family = AF_INET6;
2139                         d->rtaddr.sin6_len = sizeof(d->rtaddr);
2140                         if (in6_recoverscope(&d->rtaddr, &dr->rtaddr,
2141                             dr->ifp) != 0)
2142                                 log(LOG_ERR,
2143                                     "scope error in "
2144                                     "default router list (%s)\n",
2145                                     ip6_sprintf(&dr->rtaddr));
2146                         d->flags = dr->flags;
2147                         d->rtlifetime = dr->rtlifetime;
2148                         d->expire = dr->expire;
2149                         d->if_index = dr->ifp->if_index;
2150                 } else
2151                         panic("buffer too short");
2152
2153                 error = SYSCTL_OUT(req, buf, sizeof(*d));
2154                 if (error)
2155                         break;
2156         }
2157
2158         return (error);
2159 }
2160
2161 static int
2162 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
2163 {
2164         int error;
2165         char buf[1024];
2166         struct in6_prefix *p, *pe;
2167         struct nd_prefix *pr;
2168
2169         if (req->newptr)
2170                 return EPERM;
2171         error = 0;
2172
2173         for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
2174                 u_short advrtrs;
2175                 size_t advance;
2176                 struct sockaddr_in6 *sin6, *s6;
2177                 struct nd_pfxrouter *pfr;
2178
2179                 p = (struct in6_prefix *)buf;
2180                 pe = (struct in6_prefix *)(buf + sizeof(buf));
2181
2182                 if (p + 1 <= pe) {
2183                         bzero(p, sizeof(*p));
2184                         sin6 = (struct sockaddr_in6 *)(p + 1);
2185
2186                         p->prefix = pr->ndpr_prefix;
2187                         if (in6_recoverscope(&p->prefix,
2188                             &p->prefix.sin6_addr, pr->ndpr_ifp) != 0)
2189                                 log(LOG_ERR,
2190                                     "scope error in prefix list (%s)\n",
2191                                     ip6_sprintf(&p->prefix.sin6_addr));
2192                         p->raflags = pr->ndpr_raf;
2193                         p->prefixlen = pr->ndpr_plen;
2194                         p->vltime = pr->ndpr_vltime;
2195                         p->pltime = pr->ndpr_pltime;
2196                         p->if_index = pr->ndpr_ifp->if_index;
2197                         p->expire = pr->ndpr_expire;
2198                         p->refcnt = pr->ndpr_refcnt;
2199                         p->flags = pr->ndpr_stateflags;
2200                         p->origin = PR_ORIG_RA;
2201                         advrtrs = 0;
2202                         for (pfr = pr->ndpr_advrtrs.lh_first; pfr;
2203                              pfr = pfr->pfr_next) {
2204                                 if ((void *)&sin6[advrtrs + 1] > (void *)pe) {
2205                                         advrtrs++;
2206                                         continue;
2207                                 }
2208                                 s6 = &sin6[advrtrs];
2209                                 bzero(s6, sizeof(*s6));
2210                                 s6->sin6_family = AF_INET6;
2211                                 s6->sin6_len = sizeof(*sin6);
2212                                 if (in6_recoverscope(s6, &pfr->router->rtaddr,
2213                                     pfr->router->ifp) != 0)
2214                                         log(LOG_ERR,
2215                                             "scope error in "
2216                                             "prefix list (%s)\n",
2217                                             ip6_sprintf(&pfr->router->rtaddr));
2218                                 advrtrs++;
2219                         }
2220                         p->advrtrs = advrtrs;
2221                 } else
2222                         panic("buffer too short");
2223
2224                 advance = sizeof(*p) + sizeof(*sin6) * advrtrs;
2225                 error = SYSCTL_OUT(req, buf, advance);
2226                 if (error)
2227                         break;
2228         }
2229
2230         return (error);
2231 }