sys/netinet6/nd6.c

   1 /*      $FreeBSD: src/sys/netinet6/nd6.c,v 1.2.2.15 2003/05/06 06:46:58 suz Exp $       */
   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 /*
  34  * XXX
  35  * KAME 970409 note:
  36  * BSD/OS version heavily modifies this code, related to llinfo.
  37  * Since we don't have BSD/OS version of net/route.c in our hand,
  38  * I left the code mostly as it was in 970310.  -- itojun
  39  */
  40
  41 #include "opt_inet.h"
  42 #include "opt_inet6.h"
  43
  44 #include <sys/param.h>
  45 #include <sys/systm.h>
  46 #include <sys/callout.h>
  47 #include <sys/malloc.h>
  48 #include <sys/mbuf.h>
  49 #include <sys/socket.h>
  50 #include <sys/sockio.h>
  51 #include <sys/time.h>
  52 #include <sys/kernel.h>
  53 #include <sys/protosw.h>
  54 #include <sys/errno.h>
  55 #include <sys/syslog.h>
  56 #include <sys/queue.h>
  57 #include <sys/sysctl.h>
  58 #include <sys/mutex.h>
  59
  60 #include <sys/thread2.h>
  61 #include <sys/mutex2.h>
  62
  63 #include <net/if.h>
  64 #include <net/if_dl.h>
  65 #include <net/if_types.h>
  66 #include <net/if_atm.h>
  67 #include <net/route.h>
  68
  69 #include <netinet/in.h>
  70 #include <netinet/if_ether.h>
  71 #include <netinet6/in6_var.h>
  72 #include <netinet/ip6.h>
  73 #include <netinet6/ip6_var.h>
  74 #include <netinet6/nd6.h>
  75 #include <netinet6/in6_prefix.h>
  76 #include <netinet/icmp6.h>
  77
  78 #include <net/net_osdep.h>
  79
  80 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
  81 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
  82
  83 #define SIN6(s) ((struct sockaddr_in6 *)s)
  84 #define SDL(s) ((struct sockaddr_dl *)s)
  85
  86 /* timer values */
  87 int     nd6_prune       = 1;    /* walk list every 1 seconds */
  88 int     nd6_delay       = 5;    /* delay first probe time 5 second */
  89 int     nd6_umaxtries   = 3;    /* maximum unicast query */
  90 int     nd6_mmaxtries   = 3;    /* maximum multicast query */
  91 int     nd6_useloopback = 1;    /* use loopback interface for local traffic */
  92 int     nd6_gctimer     = (60 * 60 * 24); /* 1 day: garbage collection timer */
  93
  94 /* preventing too many loops in ND option parsing */
  95 int nd6_maxndopt = 10;  /* max # of ND options allowed */
  96
  97 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */
  98
  99 #ifdef ND6_DEBUG
 100 int nd6_debug = 1;
 101 #else
 102 int nd6_debug = 0;
 103 #endif
 104
 105 /* for debugging? */
 106 static int nd6_inuse, nd6_allocated;
 107
 108 struct llinfo_nd6 llinfo_nd6 = {&llinfo_nd6, &llinfo_nd6};
 109 struct nd_drhead nd_defrouter;
 110 struct nd_prhead nd_prefix = { 0 };
 111 struct mtx nd6_mtx = MTX_INITIALIZER;
 112
 113 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL;
 114 static struct sockaddr_in6 all1_sa;
 115
 116 static void nd6_setmtu0 (struct ifnet *, struct nd_ifinfo *);
 117 static void nd6_slowtimo (void *);
 118 static int regen_tmpaddr (struct in6_ifaddr *);
 119
 120 struct callout nd6_slowtimo_ch;
 121 struct callout nd6_timer_ch;
 122 extern struct callout in6_tmpaddrtimer_ch;
 123
 124 void
 125 nd6_init(void)
 126 {
 127         static int nd6_init_done = 0;
 128         int i;
 129
 130         if (nd6_init_done) {
 131                 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n");
 132                 return;
 133         }
 134
 135         all1_sa.sin6_family = AF_INET6;
 136         all1_sa.sin6_len = sizeof(struct sockaddr_in6);
 137         for (i = 0; i < sizeof(all1_sa.sin6_addr); i++)
 138                 all1_sa.sin6_addr.s6_addr[i] = 0xff;
 139
 140         /* initialization of the default router list */
 141         TAILQ_INIT(&nd_defrouter);
 142
 143         nd6_init_done = 1;
 144
 145         /* start timer */
 146         callout_init(&nd6_slowtimo_ch);
 147         callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
 148             nd6_slowtimo, NULL);
 149 }
 150
 151 struct nd_ifinfo *
 152 nd6_ifattach(struct ifnet *ifp)
 153 {
 154         struct nd_ifinfo *nd;
 155
 156         nd = (struct nd_ifinfo *)kmalloc(sizeof(*nd), M_IP6NDP,
 157             M_WAITOK | M_ZERO);
 158
 159         nd->initialized = 1;
 160
 161         nd->linkmtu = ifindex2ifnet[ifp->if_index]->if_mtu;
 162         nd->chlim = IPV6_DEFHLIM;
 163         nd->basereachable = REACHABLE_TIME;
 164         nd->reachable = ND_COMPUTE_RTIME(nd->basereachable);
 165         nd->retrans = RETRANS_TIMER;
 166         nd->receivedra = 0;
 167
 168         /*
 169          * Note that the default value of ip6_accept_rtadv is 0, which means
 170          * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV
 171          * here.
 172          */
 173         nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV);
 174
 175         /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */
 176         nd6_setmtu0(ifp, nd);
 177         return nd;
 178 }
 179
 180 void
 181 nd6_ifdetach(struct nd_ifinfo *nd)
 182 {
 183         kfree(nd, M_IP6NDP);
 184 }
 185
 186 /*
 187  * Reset ND level link MTU. This function is called when the physical MTU
 188  * changes, which means we might have to adjust the ND level MTU.
 189  */
 190 void
 191 nd6_setmtu(struct ifnet *ifp)
 192 {
 193         nd6_setmtu0(ifp, ND_IFINFO(ifp));
 194 }
 195
 196 /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */
 197 void
 198 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi)
 199 {
 200         u_long oldmaxmtu;
 201         u_long oldlinkmtu;
 202
 203         oldmaxmtu = ndi->maxmtu;
 204         oldlinkmtu = ndi->linkmtu;
 205
 206         switch (ifp->if_type) {
 207         case IFT_ETHER:
 208                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
 209                 break;
 210         case IFT_ATM:
 211                 ndi->maxmtu = MIN(ATMMTU, ifp->if_mtu);
 212                 break;
 213         case IFT_IEEE1394:      /* XXX should be IEEE1394MTU(1500) */
 214                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
 215                 break;
 216 #ifdef IFT_IEEE80211
 217         case IFT_IEEE80211:     /* XXX should be IEEE80211MTU(1500) */
 218                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
 219                 break;
 220 #endif
 221         default:
 222                 ndi->maxmtu = ifp->if_mtu;
 223                 break;
 224         }
 225
 226         if (oldmaxmtu != ndi->maxmtu) {
 227                 /*
 228                  * If the ND level MTU is not set yet, or if the maxmtu
 229                  * is reset to a smaller value than the ND level MTU,
 230                  * also reset the ND level MTU.
 231                  */
 232                 if (ndi->linkmtu == 0 ||
 233                     ndi->maxmtu < ndi->linkmtu) {
 234                         ndi->linkmtu = ndi->maxmtu;
 235                         /* also adjust in6_maxmtu if necessary. */
 236                         if (oldlinkmtu == 0) {
 237                                 /*
 238                                  * XXX: the case analysis is grotty, but
 239                                  * it is not efficient to call in6_setmaxmtu()
 240                                  * here when we are during the initialization
 241                                  * procedure.
 242                                  */
 243                                 if (in6_maxmtu < ndi->linkmtu)
 244                                         in6_maxmtu = ndi->linkmtu;
 245                         } else
 246                                 in6_setmaxmtu();
 247                 }
 248         }
 249 #undef MIN
 250 }
 251
 252 void
 253 nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
 254 {
 255         bzero(ndopts, sizeof(*ndopts));
 256         ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
 257         ndopts->nd_opts_last
 258                 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
 259
 260         if (icmp6len == 0) {
 261                 ndopts->nd_opts_done = 1;
 262                 ndopts->nd_opts_search = NULL;
 263         }
 264 }
 265
 266 /*
 267  * Take one ND option.
 268  */
 269 struct nd_opt_hdr *
 270 nd6_option(union nd_opts *ndopts)
 271 {
 272         struct nd_opt_hdr *nd_opt;
 273         int olen;
 274
 275         if (!ndopts)
 276                 panic("ndopts == NULL in nd6_option");
 277         if (!ndopts->nd_opts_last)
 278                 panic("uninitialized ndopts in nd6_option");
 279         if (!ndopts->nd_opts_search)
 280                 return NULL;
 281         if (ndopts->nd_opts_done)
 282                 return NULL;
 283
 284         nd_opt = ndopts->nd_opts_search;
 285
 286         /* make sure nd_opt_len is inside the buffer */
 287         if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) {
 288                 bzero(ndopts, sizeof(*ndopts));
 289                 return NULL;
 290         }
 291
 292         olen = nd_opt->nd_opt_len << 3;
 293         if (olen == 0) {
 294                 /*
 295                  * Message validation requires that all included
 296                  * options have a length that is greater than zero.
 297                  */
 298                 bzero(ndopts, sizeof(*ndopts));
 299                 return NULL;
 300         }
 301
 302         ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen);
 303         if (ndopts->nd_opts_search > ndopts->nd_opts_last) {
 304                 /* option overruns the end of buffer, invalid */
 305                 bzero(ndopts, sizeof(*ndopts));
 306                 return NULL;
 307         } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) {
 308                 /* reached the end of options chain */
 309                 ndopts->nd_opts_done = 1;
 310                 ndopts->nd_opts_search = NULL;
 311         }
 312         return nd_opt;
 313 }
 314
 315 /*
 316  * Parse multiple ND options.
 317  * This function is much easier to use, for ND routines that do not need
 318  * multiple options of the same type.
 319  */
 320 int
 321 nd6_options(union nd_opts *ndopts)
 322 {
 323         struct nd_opt_hdr *nd_opt;
 324         int i = 0;
 325
 326         if (!ndopts)
 327                 panic("ndopts == NULL in nd6_options");
 328         if (!ndopts->nd_opts_last)
 329                 panic("uninitialized ndopts in nd6_options");
 330         if (!ndopts->nd_opts_search)
 331                 return 0;
 332
 333         while (1) {
 334                 nd_opt = nd6_option(ndopts);
 335                 if (!nd_opt && !ndopts->nd_opts_last) {
 336                         /*
 337                          * Message validation requires that all included
 338                          * options have a length that is greater than zero.
 339                          */
 340                         icmp6stat.icp6s_nd_badopt++;
 341                         bzero(ndopts, sizeof(*ndopts));
 342                         return -1;
 343                 }
 344
 345                 if (!nd_opt)
 346                         goto skip1;
 347
 348                 switch (nd_opt->nd_opt_type) {
 349                 case ND_OPT_SOURCE_LINKADDR:
 350                 case ND_OPT_TARGET_LINKADDR:
 351                 case ND_OPT_MTU:
 352                 case ND_OPT_REDIRECTED_HEADER:
 353                         if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
 354                                 nd6log((LOG_INFO,
 355                                     "duplicated ND6 option found (type=%d)\n",
 356                                     nd_opt->nd_opt_type));
 357                                 /* XXX bark? */
 358                         } else {
 359                                 ndopts->nd_opt_array[nd_opt->nd_opt_type]
 360                                         = nd_opt;
 361                         }
 362                         break;
 363                 case ND_OPT_PREFIX_INFORMATION:
 364                         if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) {
 365                                 ndopts->nd_opt_array[nd_opt->nd_opt_type]
 366                                         = nd_opt;
 367                         }
 368                         ndopts->nd_opts_pi_end =
 369                                 (struct nd_opt_prefix_info *)nd_opt;
 370                         break;
 371                 default:
 372                         /*
 373                          * Unknown options must be silently ignored,
 374                          * to accomodate future extension to the protocol.
 375                          */
 376                         nd6log((LOG_DEBUG,
 377                             "nd6_options: unsupported option %d - "
 378                             "option ignored\n", nd_opt->nd_opt_type));
 379                 }
 380
 381 skip1:
 382                 i++;
 383                 if (i > nd6_maxndopt) {
 384                         icmp6stat.icp6s_nd_toomanyopt++;
 385                         nd6log((LOG_INFO, "too many loop in nd opt\n"));
 386                         break;
 387                 }
 388
 389                 if (ndopts->nd_opts_done)
 390                         break;
 391         }
 392
 393         return 0;
 394 }
 395
 396 /*
 397  * ND6 timer routine to expire default route list and prefix list
 398  */
 399 void
 400 nd6_timer(void *ignored_arg)
 401 {
 402         struct llinfo_nd6 *ln;
 403         struct nd_defrouter *dr;
 404         struct nd_prefix *pr;
 405         struct ifnet *ifp;
 406         struct in6_ifaddr *ia6, *nia6;
 407         struct in6_addrlifetime *lt6;
 408
 409         mtx_lock(&nd6_mtx);
 410         callout_reset(&nd6_timer_ch, nd6_prune * hz,
 411                       nd6_timer, NULL);
 412
 413         ln = llinfo_nd6.ln_next;
 414         while (ln && ln != &llinfo_nd6) {
 415                 struct rtentry *rt;
 416                 struct sockaddr_in6 *dst;
 417                 struct llinfo_nd6 *next = ln->ln_next;
 418                 /* XXX: used for the DELAY case only: */
 419                 struct nd_ifinfo *ndi = NULL;
 420
 421                 if ((rt = ln->ln_rt) == NULL) {
 422                         ln = next;
 423                         continue;
 424                 }
 425                 if ((ifp = rt->rt_ifp) == NULL) {
 426                         ln = next;
 427                         continue;
 428                 }
 429                 ndi = ND_IFINFO(ifp);
 430                 dst = (struct sockaddr_in6 *)rt_key(rt);
 431
 432                 if (ln->ln_expire > time_second) {
 433                         ln = next;
 434                         continue;
 435                 }
 436
 437                 /* sanity check */
 438                 if (!rt)
 439                         panic("rt=0 in nd6_timer(ln=%p)", ln);
 440                 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln)
 441                         panic("rt_llinfo(%p) is not equal to ln(%p)",
 442                               rt->rt_llinfo, ln);
 443                 if (!dst)
 444                         panic("dst=0 in nd6_timer(ln=%p)", ln);
 445
 446                 switch (ln->ln_state) {
 447                 case ND6_LLINFO_INCOMPLETE:
 448                         if (ln->ln_asked < nd6_mmaxtries) {
 449                                 ln->ln_asked++;
 450                                 ln->ln_expire = time_second +
 451                                         ND_IFINFO(ifp)->retrans / 1000;
 452                                 nd6_ns_output(ifp, NULL, &dst->sin6_addr,
 453                                         ln, 0);
 454                         } else {
 455                                 struct mbuf *m = ln->ln_hold;
 456                                 if (m) {
 457                                         if (rt->rt_ifp) {
 458                                                 /*
 459                                                  * Fake rcvif to make ICMP error
 460                                                  * more helpful in diagnosing
 461                                                  * for the receiver.
 462                                                  * XXX: should we consider
 463                                                  * older rcvif?
 464                                                  */
 465                                                 m->m_pkthdr.rcvif = rt->rt_ifp;
 466                                         }
 467                                         icmp6_error(m, ICMP6_DST_UNREACH,
 468                                                     ICMP6_DST_UNREACH_ADDR, 0);
 469                                         ln->ln_hold = NULL;
 470                                 }
 471                                 next = nd6_free(rt);
 472                         }
 473                         break;
 474                 case ND6_LLINFO_REACHABLE:
 475                         if (ln->ln_expire) {
 476                                 ln->ln_state = ND6_LLINFO_STALE;
 477                                 ln->ln_expire = time_second + nd6_gctimer;
 478                         }
 479                         break;
 480
 481                 case ND6_LLINFO_STALE:
 482                         /* Garbage Collection(RFC 2461 5.3) */
 483                         if (ln->ln_expire)
 484                                 next = nd6_free(rt);
 485                         break;
 486
 487                 case ND6_LLINFO_DELAY:
 488                         if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD)) {
 489                                 /* We need NUD */
 490                                 ln->ln_asked = 1;
 491                                 ln->ln_state = ND6_LLINFO_PROBE;
 492                                 ln->ln_expire = time_second +
 493                                         ndi->retrans / 1000;
 494                                 nd6_ns_output(ifp, &dst->sin6_addr,
 495                                               &dst->sin6_addr,
 496                                               ln, 0);
 497                         } else {
 498                                 ln->ln_state = ND6_LLINFO_STALE; /* XXX */
 499                                 ln->ln_expire = time_second + nd6_gctimer;
 500                         }
 501                         break;
 502                 case ND6_LLINFO_PROBE:
 503                         if (ln->ln_asked < nd6_umaxtries) {
 504                                 ln->ln_asked++;
 505                                 ln->ln_expire = time_second +
 506                                         ND_IFINFO(ifp)->retrans / 1000;
 507                                 nd6_ns_output(ifp, &dst->sin6_addr,
 508                                                &dst->sin6_addr, ln, 0);
 509                         } else {
 510                                 next = nd6_free(rt);
 511                         }
 512                         break;
 513                 }
 514                 ln = next;
 515         }
 516
 517         /* expire default router list */
 518         dr = TAILQ_FIRST(&nd_defrouter);
 519         while (dr) {
 520                 if (dr->expire && dr->expire < time_second) {
 521                         struct nd_defrouter *t;
 522                         t = TAILQ_NEXT(dr, dr_entry);
 523                         defrtrlist_del(dr);
 524                         dr = t;
 525                 } else {
 526                         dr = TAILQ_NEXT(dr, dr_entry);
 527                 }
 528         }
 529
 530         /*
 531          * expire interface addresses.
 532          * in the past the loop was inside prefix expiry processing.
 533          * However, from a stricter speci-confrmance standpoint, we should
 534          * rather separate address lifetimes and prefix lifetimes.
 535          */
 536 addrloop:
 537         for (ia6 = in6_ifaddr; ia6; ia6 = nia6) {
 538                 nia6 = ia6->ia_next;
 539                 /* check address lifetime */
 540                 lt6 = &ia6->ia6_lifetime;
 541                 if (IFA6_IS_INVALID(ia6)) {
 542                         int regen = 0;
 543
 544                         /*
 545                          * If the expiring address is temporary, try
 546                          * regenerating a new one.  This would be useful when
 547                          * we suspended a laptop PC, then turned it on after a
 548                          * period that could invalidate all temporary
 549                          * addresses.  Although we may have to restart the
 550                          * loop (see below), it must be after purging the
 551                          * address.  Otherwise, we'd see an infinite loop of
 552                          * regeneration.
 553                          */
 554                         if (ip6_use_tempaddr &&
 555                             (ia6->ia6_flags & IN6_IFF_TEMPORARY)) {
 556                                 if (regen_tmpaddr(ia6) == 0)
 557                                         regen = 1;
 558                         }
 559
 560                         in6_purgeaddr(&ia6->ia_ifa);
 561
 562                         if (regen)
 563                                 goto addrloop; /* XXX: see below */
 564                 }
 565                 if (IFA6_IS_DEPRECATED(ia6)) {
 566                         int oldflags = ia6->ia6_flags;
 567
 568                         ia6->ia6_flags |= IN6_IFF_DEPRECATED;
 569
 570                         /*
 571                          * If a temporary address has just become deprecated,
 572                          * regenerate a new one if possible.
 573                          */
 574                         if (ip6_use_tempaddr &&
 575                             (ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
 576                             !(oldflags & IN6_IFF_DEPRECATED)) {
 577
 578                                 if (regen_tmpaddr(ia6) == 0) {
 579                                         /*
 580                                          * A new temporary address is
 581                                          * generated.
 582                                          * XXX: this means the address chain
 583                                          * has changed while we are still in
 584                                          * the loop.  Although the change
 585                                          * would not cause disaster (because
 586                                          * it's not a deletion, but an
 587                                          * addition,) we'd rather restart the
 588                                          * loop just for safety.  Or does this
 589                                          * significantly reduce performance??
 590                                          */
 591                                         goto addrloop;
 592                                 }
 593                         }
 594                 } else {
 595                         /*
 596                          * A new RA might have made a deprecated address
 597                          * preferred.
 598                          */
 599                         ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
 600                 }
 601         }
 602
 603         /* expire prefix list */
 604         pr = nd_prefix.lh_first;
 605         while (pr) {
 606                 /*
 607                  * check prefix lifetime.
 608                  * since pltime is just for autoconf, pltime processing for
 609                  * prefix is not necessary.
 610                  */
 611                 if (pr->ndpr_expire && pr->ndpr_expire < time_second) {
 612                         struct nd_prefix *t;
 613                         t = pr->ndpr_next;
 614
 615                         /*
 616                          * address expiration and prefix expiration are
 617                          * separate.  NEVER perform in6_purgeaddr here.
 618                          */
 619
 620                         prelist_remove(pr);
 621                         pr = t;
 622                 } else
 623                         pr = pr->ndpr_next;
 624         }
 625         mtx_unlock(&nd6_mtx);
 626 }
 627
 628 static int
 629 regen_tmpaddr(struct in6_ifaddr *ia6) /* deprecated/invalidated temporary
 630                                          address */
 631 {
 632         struct ifaddr_container *ifac;
 633         struct ifnet *ifp;
 634         struct in6_ifaddr *public_ifa6 = NULL;
 635
 636         ifp = ia6->ia_ifa.ifa_ifp;
 637         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
 638                 struct ifaddr *ifa = ifac->ifa;
 639                 struct in6_ifaddr *it6;
 640
 641                 if (ifa->ifa_addr->sa_family != AF_INET6)
 642                         continue;
 643
 644                 it6 = (struct in6_ifaddr *)ifa;
 645
 646                 /* ignore no autoconf addresses. */
 647                 if (!(it6->ia6_flags & IN6_IFF_AUTOCONF))
 648                         continue;
 649
 650                 /* ignore autoconf addresses with different prefixes. */
 651                 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
 652                         continue;
 653
 654                 /*
 655                  * Now we are looking at an autoconf address with the same
 656                  * prefix as ours.  If the address is temporary and is still
 657                  * preferred, do not create another one.  It would be rare, but
 658                  * could happen, for example, when we resume a laptop PC after
 659                  * a long period.
 660                  */
 661                 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) &&
 662                     !IFA6_IS_DEPRECATED(it6)) {
 663                         public_ifa6 = NULL;
 664                         break;
 665                 }
 666
 667                 /*
 668                  * This is a public autoconf address that has the same prefix
 669                  * as ours.  If it is preferred, keep it.  We can't break the
 670                  * loop here, because there may be a still-preferred temporary
 671                  * address with the prefix.
 672                  */
 673                 if (!IFA6_IS_DEPRECATED(it6))
 674                     public_ifa6 = it6;
 675         }
 676
 677         if (public_ifa6 != NULL) {
 678                 int e;
 679
 680                 if ((e = in6_tmpifadd(public_ifa6, 0)) != 0) {
 681                         log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
 682                             " tmp addr,errno=%d\n", e);
 683                         return (-1);
 684                 }
 685                 return (0);
 686         }
 687
 688         return (-1);
 689 }
 690
 691 /*
 692  * Nuke neighbor cache/prefix/default router management table, right before
 693  * ifp goes away.
 694  */
 695 void
 696 nd6_purge(struct ifnet *ifp)
 697 {
 698         struct llinfo_nd6 *ln, *nln;
 699         struct nd_defrouter *dr, *ndr, drany;
 700         struct nd_prefix *pr, *npr;
 701
 702         /* Nuke default router list entries toward ifp */
 703         if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
 704                 /*
 705                  * The first entry of the list may be stored in
 706                  * the routing table, so we'll delete it later.
 707                  */
 708                 for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = ndr) {
 709                         ndr = TAILQ_NEXT(dr, dr_entry);
 710                         if (dr->ifp == ifp)
 711                                 defrtrlist_del(dr);
 712                 }
 713                 dr = TAILQ_FIRST(&nd_defrouter);
 714                 if (dr->ifp == ifp)
 715                         defrtrlist_del(dr);
 716         }
 717
 718         /* Nuke prefix list entries toward ifp */
 719         for (pr = nd_prefix.lh_first; pr; pr = npr) {
 720                 npr = pr->ndpr_next;
 721                 if (pr->ndpr_ifp == ifp) {
 722                         /*
 723                          * Previously, pr->ndpr_addr is removed as well,
 724                          * but I strongly believe we don't have to do it.
 725                          * nd6_purge() is only called from in6_ifdetach(),
 726                          * which removes all the associated interface addresses
 727                          * by itself.
 728                          * (jinmei@kame.net 20010129)
 729                          */
 730                         prelist_remove(pr);
 731                 }
 732         }
 733
 734         /* cancel default outgoing interface setting */
 735         if (nd6_defifindex == ifp->if_index)
 736                 nd6_setdefaultiface(0);
 737
 738         if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
 739                 /* refresh default router list */
 740                 bzero(&drany, sizeof(drany));
 741                 defrouter_delreq(&drany, 0);
 742                 defrouter_select();
 743         }
 744
 745         /*
 746          * Nuke neighbor cache entries for the ifp.
 747          * Note that rt->rt_ifp may not be the same as ifp,
 748          * due to KAME goto ours hack.  See RTM_RESOLVE case in
 749          * nd6_rtrequest(), and ip6_input().
 750          */
 751         ln = llinfo_nd6.ln_next;
 752         while (ln && ln != &llinfo_nd6) {
 753                 struct rtentry *rt;
 754                 struct sockaddr_dl *sdl;
 755
 756                 nln = ln->ln_next;
 757                 rt = ln->ln_rt;
 758                 if (rt && rt->rt_gateway &&
 759                     rt->rt_gateway->sa_family == AF_LINK) {
 760                         sdl = (struct sockaddr_dl *)rt->rt_gateway;
 761                         if (sdl->sdl_index == ifp->if_index)
 762                                 nln = nd6_free(rt);
 763                 }
 764                 ln = nln;
 765         }
 766 }
 767
 768 struct rtentry *
 769 nd6_lookup(struct in6_addr *addr6, int create, struct ifnet *ifp)
 770 {
 771         struct rtentry *rt;
 772         struct sockaddr_in6 sin6;
 773
 774         bzero(&sin6, sizeof(sin6));
 775         sin6.sin6_len = sizeof(struct sockaddr_in6);
 776         sin6.sin6_family = AF_INET6;
 777         sin6.sin6_addr = *addr6;
 778
 779         if (create)
 780                 rt = rtlookup((struct sockaddr *)&sin6);
 781         else
 782                 rt = rtpurelookup((struct sockaddr *)&sin6);
 783         if (rt && !(rt->rt_flags & RTF_LLINFO)) {
 784                 /*
 785                  * This is the case for the default route.
 786                  * If we want to create a neighbor cache for the address, we
 787                  * should free the route for the destination and allocate an
 788                  * interface route.
 789                  */
 790                 if (create) {
 791                         --rt->rt_refcnt;
 792                         rt = NULL;
 793                 }
 794         }
 795         if (!rt) {
 796                 if (create && ifp) {
 797                         int e;
 798
 799                         /*
 800                          * If no route is available and create is set,
 801                          * we allocate a host route for the destination
 802                          * and treat it like an interface route.
 803                          * This hack is necessary for a neighbor which can't
 804                          * be covered by our own prefix.
 805                          */
 806                         struct ifaddr *ifa =
 807                                 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp);
 808                         if (ifa == NULL)
 809                                 return (NULL);
 810
 811                         /*
 812                          * Create a new route.  RTF_LLINFO is necessary
 813                          * to create a Neighbor Cache entry for the
 814                          * destination in nd6_rtrequest which will be
 815                          * called in rtrequest via ifa->ifa_rtrequest.
 816                          */
 817                         if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6,
 818                                            ifa->ifa_addr,
 819                                            (struct sockaddr *)&all1_sa,
 820                                            (ifa->ifa_flags |
 821                                             RTF_HOST | RTF_LLINFO) &
 822                                            ~RTF_CLONING,
 823                                            &rt)) != 0)
 824                                 log(LOG_ERR,
 825                                     "nd6_lookup: failed to add route for a "
 826                                     "neighbor(%s), errno=%d\n",
 827                                     ip6_sprintf(addr6), e);
 828                         if (rt == NULL)
 829                                 return (NULL);
 830                         if (rt->rt_llinfo) {
 831                                 struct llinfo_nd6 *ln =
 832                                         (struct llinfo_nd6 *)rt->rt_llinfo;
 833                                 ln->ln_state = ND6_LLINFO_NOSTATE;
 834                         }
 835                 } else
 836                         return (NULL);
 837         }
 838         rt->rt_refcnt--;
 839         /*
 840          * Validation for the entry.
 841          * Note that the check for rt_llinfo is necessary because a cloned
 842          * route from a parent route that has the L flag (e.g. the default
 843          * route to a p2p interface) may have the flag, too, while the
 844          * destination is not actually a neighbor.
 845          * XXX: we can't use rt->rt_ifp to check for the interface, since
 846          *      it might be the loopback interface if the entry is for our
 847          *      own address on a non-loopback interface. Instead, we should
 848          *      use rt->rt_ifa->ifa_ifp, which would specify the REAL
 849          *      interface.
 850          */
 851         if ((rt->rt_flags & RTF_GATEWAY) || !(rt->rt_flags & RTF_LLINFO) ||
 852             rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL ||
 853             (ifp && rt->rt_ifa->ifa_ifp != ifp)) {
 854                 if (create) {
 855                         log(LOG_DEBUG, "nd6_lookup: failed to lookup %s (if = %s)\n",
 856                             ip6_sprintf(addr6), ifp ? if_name(ifp) : "unspec");
 857                         /* xxx more logs... kazu */
 858                 }
 859                 return (NULL);
 860         }
 861         return (rt);
 862 }
 863
 864 /*
 865  * Detect if a given IPv6 address identifies a neighbor on a given link.
 866  * XXX: should take care of the destination of a p2p link?
 867  */
 868 int
 869 nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
 870 {
 871         struct ifaddr_container *ifac;
 872         int i;
 873
 874 #define IFADDR6(a) ((((struct in6_ifaddr *)(a))->ia_addr).sin6_addr)
 875 #define IFMASK6(a) ((((struct in6_ifaddr *)(a))->ia_prefixmask).sin6_addr)
 876
 877         /*
 878          * A link-local address is always a neighbor.
 879          * XXX: we should use the sin6_scope_id field rather than the embedded
 880          * interface index.
 881          */
 882         if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr) &&
 883             ntohs(*(u_int16_t *)&addr->sin6_addr.s6_addr[2]) == ifp->if_index)
 884                 return (1);
 885
 886         /*
 887          * If the address matches one of our addresses,
 888          * it should be a neighbor.
 889          */
 890         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
 891                 struct ifaddr *ifa = ifac->ifa;
 892
 893                 if (ifa->ifa_addr->sa_family != AF_INET6)
 894                         next: continue;
 895
 896                 for (i = 0; i < 4; i++) {
 897                         if ((IFADDR6(ifa).s6_addr32[i] ^
 898                              addr->sin6_addr.s6_addr32[i]) &
 899                             IFMASK6(ifa).s6_addr32[i])
 900                                 goto next;
 901                 }
 902                 return (1);
 903         }
 904
 905         /*
 906          * Even if the address matches none of our addresses, it might be
 907          * in the neighbor cache.
 908          */
 909         if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL)
 910                 return (1);
 911
 912         return (0);
 913 #undef IFADDR6
 914 #undef IFMASK6
 915 }
 916
 917 /*
 918  * Free an nd6 llinfo entry.
 919  */
 920 struct llinfo_nd6 *
 921 nd6_free(struct rtentry *rt)
 922 {
 923         struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next;
 924         struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
 925         struct nd_defrouter *dr;
 926
 927         /*
 928          * we used to have kpfctlinput(PRC_HOSTDEAD) here.
 929          * even though it is not harmful, it was not really necessary.
 930          */
 931
 932         if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
 933                 mtx_lock(&nd6_mtx);
 934                 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
 935                                       rt->rt_ifp);
 936
 937                 if (ln->ln_router || dr) {
 938                         /*
 939                          * rt6_flush must be called whether or not the neighbor
 940                          * is in the Default Router List.
 941                          * See a corresponding comment in nd6_na_input().
 942                          */
 943                         rt6_flush(&in6, rt->rt_ifp);
 944                 }
 945
 946                 if (dr) {
 947                         /*
 948                          * Unreachablity of a router might affect the default
 949                          * router selection and on-link detection of advertised
 950                          * prefixes.
 951                          */
 952
 953                         /*
 954                          * Temporarily fake the state to choose a new default
 955                          * router and to perform on-link determination of
 956                          * prefixes correctly.
 957                          * Below the state will be set correctly,
 958                          * or the entry itself will be deleted.
 959                          */
 960                         ln->ln_state = ND6_LLINFO_INCOMPLETE;
 961
 962                         /*
 963                          * Since defrouter_select() does not affect the
 964                          * on-link determination and MIP6 needs the check
 965                          * before the default router selection, we perform
 966                          * the check now.
 967                          */
 968                         pfxlist_onlink_check();
 969
 970                         if (dr == TAILQ_FIRST(&nd_defrouter)) {
 971                                 /*
 972                                  * It is used as the current default router,
 973                                  * so we have to move it to the end of the
 974                                  * list and choose a new one.
 975                                  * XXX: it is not very efficient if this is
 976                                  *      the only router.
 977                                  */
 978                                 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
 979                                 TAILQ_INSERT_TAIL(&nd_defrouter, dr, dr_entry);
 980
 981                                 defrouter_select();
 982                         }
 983                 }
 984                 mtx_unlock(&nd6_mtx);
 985         }
 986
 987         /*
 988          * Before deleting the entry, remember the next entry as the
 989          * return value.  We need this because pfxlist_onlink_check() above
 990          * might have freed other entries (particularly the old next entry) as
 991          * a side effect (XXX).
 992          */
 993         next = ln->ln_next;
 994
 995         /*
 996          * Detach the route from the routing tree and the list of neighbor
 997          * caches, and disable the route entry not to be used in already
 998          * cached routes.
 999          */
1000         rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
1001
1002         return (next);
1003 }
1004
1005 /*
1006  * Upper-layer reachability hint for Neighbor Unreachability Detection.
1007  *
1008  * XXX cost-effective metods?
1009  */
1010 void
1011 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force)
1012 {
1013         struct llinfo_nd6 *ln;
1014
1015         /*
1016          * If the caller specified "rt", use that.  Otherwise, resolve the
1017          * routing table by supplied "dst6".
1018          */
1019         if (!rt) {
1020                 if (!dst6)
1021                         return;
1022                 if (!(rt = nd6_lookup(dst6, 0, NULL)))
1023                         return;
1024         }
1025
1026         if ((rt->rt_flags & RTF_GATEWAY) ||
1027             !(rt->rt_flags & RTF_LLINFO) ||
1028             rt->rt_llinfo == NULL || rt->rt_gateway == NULL ||
1029             rt->rt_gateway->sa_family != AF_LINK) {
1030                 /* This is not a host route. */
1031                 return;
1032         }
1033
1034         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1035         if (ln->ln_state < ND6_LLINFO_REACHABLE)
1036                 return;
1037
1038         /*
1039          * if we get upper-layer reachability confirmation many times,
1040          * it is possible we have false information.
1041          */
1042         if (!force) {
1043                 ln->ln_byhint++;
1044                 if (ln->ln_byhint > nd6_maxnudhint)
1045                         return;
1046         }
1047
1048         ln->ln_state = ND6_LLINFO_REACHABLE;
1049         if (ln->ln_expire)
1050                 ln->ln_expire = time_second +
1051                         ND_IFINFO(rt->rt_ifp)->reachable;
1052 }
1053
1054 void
1055 nd6_rtrequest(int req, struct rtentry *rt,
1056               struct rt_addrinfo *info) /* xxx unused */
1057 {
1058         struct sockaddr *gate = rt->rt_gateway;
1059         struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1060         static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
1061         struct ifnet *ifp = rt->rt_ifp;
1062         struct ifaddr *ifa;
1063
1064         if ((rt->rt_flags & RTF_GATEWAY))
1065                 return;
1066
1067         if (nd6_need_cache(ifp) == 0 && !(rt->rt_flags & RTF_HOST)) {
1068                 /*
1069                  * This is probably an interface direct route for a link
1070                  * which does not need neighbor caches (e.g. fe80::%lo0/64).
1071                  * We do not need special treatment below for such a route.
1072                  * Moreover, the RTF_LLINFO flag which would be set below
1073                  * would annoy the ndp(8) command.
1074                  */
1075                 return;
1076         }
1077
1078         if (req == RTM_RESOLVE &&
1079             (nd6_need_cache(ifp) == 0 || /* stf case */
1080              !nd6_is_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), ifp))) {
1081                 /*
1082                  * FreeBSD and BSD/OS often make a cloned host route based
1083                  * on a less-specific route (e.g. the default route).
1084                  * If the less specific route does not have a "gateway"
1085                  * (this is the case when the route just goes to a p2p or an
1086                  * stf interface), we'll mistakenly make a neighbor cache for
1087                  * the host route, and will see strange neighbor solicitation
1088                  * for the corresponding destination.  In order to avoid the
1089                  * confusion, we check if the destination of the route is
1090                  * a neighbor in terms of neighbor discovery, and stop the
1091                  * process if not.  Additionally, we remove the LLINFO flag
1092                  * so that ndp(8) will not try to get the neighbor information
1093                  * of the destination.
1094                  */
1095                 rt->rt_flags &= ~RTF_LLINFO;
1096                 return;
1097         }
1098
1099         switch (req) {
1100         case RTM_ADD:
1101                 /*
1102                  * There is no backward compatibility :)
1103                  *
1104                  * if (!(rt->rt_flags & RTF_HOST) &&
1105                  *     SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
1106                  *         rt->rt_flags |= RTF_CLONING;
1107                  */
1108                 if (rt->rt_flags & (RTF_CLONING | RTF_LLINFO)) {
1109                         /*
1110                          * Case 1: This route should come from
1111                          * a route to interface.  RTF_LLINFO flag is set
1112                          * for a host route whose destination should be
1113                          * treated as on-link.
1114                          */
1115                         rt_setgate(rt, rt_key(rt),
1116                                    (struct sockaddr *)&null_sdl,
1117                                    RTL_DONTREPORT);
1118                         gate = rt->rt_gateway;
1119                         SDL(gate)->sdl_type = ifp->if_type;
1120                         SDL(gate)->sdl_index = ifp->if_index;
1121                         if (ln)
1122                                 ln->ln_expire = time_second;
1123 #if 1
1124                         if (ln && ln->ln_expire == 0) {
1125                                 /* kludge for desktops */
1126 #if 0
1127                                 kprintf("nd6_rtequest: time.tv_sec is zero; "
1128                                        "treat it as 1\n");
1129 #endif
1130                                 ln->ln_expire = 1;
1131                         }
1132 #endif
1133                         if ((rt->rt_flags & RTF_CLONING))
1134                                 break;
1135                 }
1136                 /*
1137                  * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here.
1138                  * We don't do that here since llinfo is not ready yet.
1139                  *
1140                  * There are also couple of other things to be discussed:
1141                  * - unsolicited NA code needs improvement beforehand
1142                  * - RFC2461 says we MAY send multicast unsolicited NA
1143                  *   (7.2.6 paragraph 4), however, it also says that we
1144                  *   SHOULD provide a mechanism to prevent multicast NA storm.
1145                  *   we don't have anything like it right now.
1146                  *   note that the mechanism needs a mutual agreement
1147                  *   between proxies, which means that we need to implement
1148                  *   a new protocol, or a new kludge.
1149                  * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA.
1150                  *   we need to check ip6forwarding before sending it.
1151                  *   (or should we allow proxy ND configuration only for
1152                  *   routers?  there's no mention about proxy ND from hosts)
1153                  */
1154 #if 0
1155                 /* XXX it does not work */
1156                 if (rt->rt_flags & RTF_ANNOUNCE)
1157                         nd6_na_output(ifp,
1158                               &SIN6(rt_key(rt))->sin6_addr,
1159                               &SIN6(rt_key(rt))->sin6_addr,
1160                               ip6_forwarding ? ND_NA_FLAG_ROUTER : 0,
1161                               1, NULL);
1162 #endif
1163                 /* FALLTHROUGH */
1164         case RTM_RESOLVE:
1165                 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) {
1166                         /*
1167                          * Address resolution isn't necessary for a point to
1168                          * point link, so we can skip this test for a p2p link.
1169                          */
1170                         if (gate->sa_family != AF_LINK ||
1171                             gate->sa_len < sizeof(null_sdl)) {
1172                                 log(LOG_DEBUG,
1173                                     "nd6_rtrequest: bad gateway value: %s\n",
1174                                     if_name(ifp));
1175                                 break;
1176                         }
1177                         SDL(gate)->sdl_type = ifp->if_type;
1178                         SDL(gate)->sdl_index = ifp->if_index;
1179                 }
1180                 if (ln != NULL)
1181                         break;  /* This happens on a route change */
1182                 /*
1183                  * Case 2: This route may come from cloning, or a manual route
1184                  * add with a LL address.
1185                  */
1186                 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln));
1187                 rt->rt_llinfo = (caddr_t)ln;
1188                 if (!ln) {
1189                         log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n");
1190                         break;
1191                 }
1192                 nd6_inuse++;
1193                 nd6_allocated++;
1194                 bzero(ln, sizeof(*ln));
1195                 ln->ln_rt = rt;
1196                 /* this is required for "ndp" command. - shin */
1197                 if (req == RTM_ADD) {
1198                         /*
1199                          * gate should have some valid AF_LINK entry,
1200                          * and ln->ln_expire should have some lifetime
1201                          * which is specified by ndp command.
1202                          */
1203                         ln->ln_state = ND6_LLINFO_REACHABLE;
1204                         ln->ln_byhint = 0;
1205                 } else {
1206                         /*
1207                          * When req == RTM_RESOLVE, rt is created and
1208                          * initialized in rtrequest(), so rt_expire is 0.
1209                          */
1210                         ln->ln_state = ND6_LLINFO_NOSTATE;
1211                         ln->ln_expire = time_second;
1212                 }
1213                 rt->rt_flags |= RTF_LLINFO;
1214                 ln->ln_next = llinfo_nd6.ln_next;
1215                 llinfo_nd6.ln_next = ln;
1216                 ln->ln_prev = &llinfo_nd6;
1217                 ln->ln_next->ln_prev = ln;
1218
1219                 /*
1220                  * check if rt_key(rt) is one of my address assigned
1221                  * to the interface.
1222                  */
1223                 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp,
1224                                           &SIN6(rt_key(rt))->sin6_addr);
1225                 if (ifa) {
1226                         caddr_t macp = nd6_ifptomac(ifp);
1227                         ln->ln_expire = 0;
1228                         ln->ln_state = ND6_LLINFO_REACHABLE;
1229                         ln->ln_byhint = 0;
1230                         if (macp) {
1231                                 bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen);
1232                                 SDL(gate)->sdl_alen = ifp->if_addrlen;
1233                         }
1234                         if (nd6_useloopback) {
1235                                 rt->rt_ifp = &loif[0];  /* XXX */
1236                                 /*
1237                                  * Make sure rt_ifa be equal to the ifaddr
1238                                  * corresponding to the address.
1239                                  * We need this because when we refer
1240                                  * rt_ifa->ia6_flags in ip6_input, we assume
1241                                  * that the rt_ifa points to the address instead
1242                                  * of the loopback address.
1243                                  */
1244                                 if (ifa != rt->rt_ifa) {
1245                                         IFAFREE(rt->rt_ifa);
1246                                         IFAREF(ifa);
1247                                         rt->rt_ifa = ifa;
1248                                 }
1249                         }
1250                 } else if (rt->rt_flags & RTF_ANNOUNCE) {
1251                         ln->ln_expire = 0;
1252                         ln->ln_state = ND6_LLINFO_REACHABLE;
1253                         ln->ln_byhint = 0;
1254
1255                         /* join solicited node multicast for proxy ND */
1256                         if (ifp->if_flags & IFF_MULTICAST) {
1257                                 struct in6_addr llsol;
1258                                 int error;
1259
1260                                 llsol = SIN6(rt_key(rt))->sin6_addr;
1261                                 llsol.s6_addr16[0] = htons(0xff02);
1262                                 llsol.s6_addr16[1] = htons(ifp->if_index);
1263                                 llsol.s6_addr32[1] = 0;
1264                                 llsol.s6_addr32[2] = htonl(1);
1265                                 llsol.s6_addr8[12] = 0xff;
1266
1267                                 if (!in6_addmulti(&llsol, ifp, &error)) {
1268                                         nd6log((LOG_ERR, "%s: failed to join "
1269                                             "%s (errno=%d)\n", if_name(ifp),
1270                                             ip6_sprintf(&llsol), error));
1271                                 }
1272                         }
1273                 }
1274                 break;
1275
1276         case RTM_DELETE:
1277                 if (!ln)
1278                         break;
1279                 /* leave from solicited node multicast for proxy ND */
1280                 if ((rt->rt_flags & RTF_ANNOUNCE) &&
1281                     (ifp->if_flags & IFF_MULTICAST)) {
1282                         struct in6_addr llsol;
1283                         struct in6_multi *in6m;
1284
1285                         llsol = SIN6(rt_key(rt))->sin6_addr;
1286                         llsol.s6_addr16[0] = htons(0xff02);
1287                         llsol.s6_addr16[1] = htons(ifp->if_index);
1288                         llsol.s6_addr32[1] = 0;
1289                         llsol.s6_addr32[2] = htonl(1);
1290                         llsol.s6_addr8[12] = 0xff;
1291
1292                         IN6_LOOKUP_MULTI(llsol, ifp, in6m);
1293                         if (in6m)
1294                                 in6_delmulti(in6m);
1295                 }
1296                 nd6_inuse--;
1297                 ln->ln_next->ln_prev = ln->ln_prev;
1298                 ln->ln_prev->ln_next = ln->ln_next;
1299                 ln->ln_prev = NULL;
1300                 rt->rt_llinfo = 0;
1301                 rt->rt_flags &= ~RTF_LLINFO;
1302                 if (ln->ln_hold)
1303                         m_freem(ln->ln_hold);
1304                 Free((caddr_t)ln);
1305         }
1306 }
1307
1308 int
1309 nd6_ioctl(u_long cmd, caddr_t   data, struct ifnet *ifp)
1310 {
1311         struct in6_drlist *drl = (struct in6_drlist *)data;
1312         struct in6_prlist *prl = (struct in6_prlist *)data;
1313         struct in6_ndireq *ndi = (struct in6_ndireq *)data;
1314         struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
1315         struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
1316         struct nd_defrouter *dr, any;
1317         struct nd_prefix *pr;
1318         struct rtentry *rt;
1319         int i = 0, error = 0;
1320
1321         switch (cmd) {
1322         case SIOCGDRLST_IN6:
1323                 /*
1324                  * obsolete API, use sysctl under net.inet6.icmp6
1325                  */
1326                 bzero(drl, sizeof(*drl));
1327                 mtx_lock(&nd6_mtx);
1328                 dr = TAILQ_FIRST(&nd_defrouter);
1329                 while (dr && i < DRLSTSIZ) {
1330                         drl->defrouter[i].rtaddr = dr->rtaddr;
1331                         if (IN6_IS_ADDR_LINKLOCAL(&drl->defrouter[i].rtaddr)) {
1332                                 /* XXX: need to this hack for KAME stack */
1333                                 drl->defrouter[i].rtaddr.s6_addr16[1] = 0;
1334                         } else
1335                                 log(LOG_ERR,
1336                                     "default router list contains a "
1337                                     "non-linklocal address(%s)\n",
1338                                     ip6_sprintf(&drl->defrouter[i].rtaddr));
1339
1340                         drl->defrouter[i].flags = dr->flags;
1341                         drl->defrouter[i].rtlifetime = dr->rtlifetime;
1342                         drl->defrouter[i].expire = dr->expire;
1343                         drl->defrouter[i].if_index = dr->ifp->if_index;
1344                         i++;
1345                         dr = TAILQ_NEXT(dr, dr_entry);
1346                 }
1347                 mtx_unlock(&nd6_mtx);
1348                 break;
1349         case SIOCGPRLST_IN6:
1350                 /*
1351                  * obsolete API, use sysctl under net.inet6.icmp6
1352                  */
1353                 /*
1354                  * XXX meaning of fields, especialy "raflags", is very
1355                  * differnet between RA prefix list and RR/static prefix list.
1356                  * how about separating ioctls into two?
1357                  */
1358                 bzero(prl, sizeof(*prl));
1359                 mtx_lock(&nd6_mtx);
1360                 pr = nd_prefix.lh_first;
1361                 while (pr && i < PRLSTSIZ) {
1362                         struct nd_pfxrouter *pfr;
1363                         int j;
1364
1365                         in6_embedscope(&prl->prefix[i].prefix,
1366                             &pr->ndpr_prefix, NULL, NULL);
1367                         prl->prefix[i].raflags = pr->ndpr_raf;
1368                         prl->prefix[i].prefixlen = pr->ndpr_plen;
1369                         prl->prefix[i].vltime = pr->ndpr_vltime;
1370                         prl->prefix[i].pltime = pr->ndpr_pltime;
1371                         prl->prefix[i].if_index = pr->ndpr_ifp->if_index;
1372                         prl->prefix[i].expire = pr->ndpr_expire;
1373
1374                         pfr = pr->ndpr_advrtrs.lh_first;
1375                         j = 0;
1376                         while (pfr) {
1377                                 if (j < DRLSTSIZ) {
1378 #define RTRADDR prl->prefix[i].advrtr[j]
1379                                         RTRADDR = pfr->router->rtaddr;
1380                                         if (IN6_IS_ADDR_LINKLOCAL(&RTRADDR)) {
1381                                                 /* XXX: hack for KAME */
1382                                                 RTRADDR.s6_addr16[1] = 0;
1383                                         } else
1384                                                 log(LOG_ERR,
1385                                                     "a router(%s) advertises "
1386                                                     "a prefix with "
1387                                                     "non-link local address\n",
1388                                                     ip6_sprintf(&RTRADDR));
1389 #undef RTRADDR
1390                                 }
1391                                 j++;
1392                                 pfr = pfr->pfr_next;
1393                         }
1394                         prl->prefix[i].advrtrs = j;
1395                         prl->prefix[i].origin = PR_ORIG_RA;
1396
1397                         i++;
1398                         pr = pr->ndpr_next;
1399                 }
1400               {
1401                 struct rr_prefix *rpp;
1402
1403                 for (rpp = LIST_FIRST(&rr_prefix); rpp;
1404                      rpp = LIST_NEXT(rpp, rp_entry)) {
1405                         if (i >= PRLSTSIZ)
1406                                 break;
1407                         in6_embedscope(&prl->prefix[i].prefix,
1408                             &pr->ndpr_prefix, NULL, NULL);
1409                         prl->prefix[i].raflags = rpp->rp_raf;
1410                         prl->prefix[i].prefixlen = rpp->rp_plen;
1411                         prl->prefix[i].vltime = rpp->rp_vltime;
1412                         prl->prefix[i].pltime = rpp->rp_pltime;
1413                         prl->prefix[i].if_index = rpp->rp_ifp->if_index;
1414                         prl->prefix[i].expire = rpp->rp_expire;
1415                         prl->prefix[i].advrtrs = 0;
1416                         prl->prefix[i].origin = rpp->rp_origin;
1417                         i++;
1418                 }
1419               }
1420                 mtx_unlock(&nd6_mtx);
1421
1422                 break;
1423         case OSIOCGIFINFO_IN6:
1424                 /* XXX: old ndp(8) assumes a positive value for linkmtu. */
1425                 bzero(&ndi->ndi, sizeof(ndi->ndi));
1426                 ndi->ndi.linkmtu = ND_IFINFO(ifp)->linkmtu;
1427                 ndi->ndi.maxmtu = ND_IFINFO(ifp)->maxmtu;
1428                 ndi->ndi.basereachable = ND_IFINFO(ifp)->basereachable;
1429                 ndi->ndi.reachable = ND_IFINFO(ifp)->reachable;
1430                 ndi->ndi.retrans = ND_IFINFO(ifp)->retrans;
1431                 ndi->ndi.flags = ND_IFINFO(ifp)->flags;
1432                 ndi->ndi.recalctm = ND_IFINFO(ifp)->recalctm;
1433                 ndi->ndi.chlim = ND_IFINFO(ifp)->chlim;
1434                 ndi->ndi.receivedra = ND_IFINFO(ifp)->receivedra;
1435                 break;
1436         case SIOCGIFINFO_IN6:
1437                 ndi->ndi = *ND_IFINFO(ifp);
1438                 break;
1439         case SIOCSIFINFO_FLAGS:
1440                 ND_IFINFO(ifp)->flags = ndi->ndi.flags;
1441                 break;
1442         case SIOCSNDFLUSH_IN6:  /* XXX: the ioctl name is confusing... */
1443                 /* flush default router list */
1444                 /*
1445                  * xxx sumikawa: should not delete route if default
1446                  * route equals to the top of default router list
1447                  */
1448                 bzero(&any, sizeof(any));
1449                 defrouter_delreq(&any, 0);
1450                 defrouter_select();
1451                 /* xxx sumikawa: flush prefix list */
1452                 break;
1453         case SIOCSPFXFLUSH_IN6:
1454             {
1455                 /* flush all the prefix advertised by routers */
1456                 struct nd_prefix *pr, *next;
1457
1458                 mtx_lock(&nd6_mtx);
1459                 for (pr = nd_prefix.lh_first; pr; pr = next) {
1460                         struct in6_ifaddr *ia, *ia_next;
1461
1462                         next = pr->ndpr_next;
1463
1464                         if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
1465                                 continue; /* XXX */
1466
1467                         /* do we really have to remove addresses as well? */
1468                         for (ia = in6_ifaddr; ia; ia = ia_next) {
1469                                 /* ia might be removed.  keep the next ptr. */
1470                                 ia_next = ia->ia_next;
1471
1472                                 if (!(ia->ia6_flags & IN6_IFF_AUTOCONF))
1473                                         continue;
1474
1475                                 if (ia->ia6_ndpr == pr)
1476                                         in6_purgeaddr(&ia->ia_ifa);
1477                         }
1478                         prelist_remove(pr);
1479                 }
1480                 mtx_unlock(&nd6_mtx);
1481                 break;
1482             }
1483         case SIOCSRTRFLUSH_IN6:
1484             {
1485                 /* flush all the default routers */
1486                 struct nd_defrouter *dr, *next;
1487
1488                 mtx_lock(&nd6_mtx);
1489                 if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
1490                         /*
1491                          * The first entry of the list may be stored in
1492                          * the routing table, so we'll delete it later.
1493                          */
1494                         for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = next) {
1495                                 next = TAILQ_NEXT(dr, dr_entry);
1496                                 defrtrlist_del(dr);
1497                         }
1498                         defrtrlist_del(TAILQ_FIRST(&nd_defrouter));
1499                 }
1500                 mtx_unlock(&nd6_mtx);
1501                 break;
1502             }
1503         case SIOCGNBRINFO_IN6:
1504             {
1505                 struct llinfo_nd6 *ln;
1506                 struct in6_addr nb_addr = nbi->addr; /* make local for safety */
1507
1508                 /*
1509                  * XXX: KAME specific hack for scoped addresses
1510                  *      XXXX: for other scopes than link-local?
1511                  */
1512                 if (IN6_IS_ADDR_LINKLOCAL(&nbi->addr) ||
1513                     IN6_IS_ADDR_MC_LINKLOCAL(&nbi->addr)) {
1514                         u_int16_t *idp = (u_int16_t *)&nb_addr.s6_addr[2];
1515
1516                         if (*idp == 0)
1517                                 *idp = htons(ifp->if_index);
1518                 }
1519
1520                 mtx_lock(&nd6_mtx);
1521                 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL) {
1522                         error = EINVAL;
1523                         mtx_unlock(&nd6_mtx);
1524                         break;
1525                 }
1526                 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1527                 nbi->state = ln->ln_state;
1528                 nbi->asked = ln->ln_asked;
1529                 nbi->isrouter = ln->ln_router;
1530                 nbi->expire = ln->ln_expire;
1531                 mtx_unlock(&nd6_mtx);
1532
1533                 break;
1534             }
1535         case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1536                 ndif->ifindex = nd6_defifindex;
1537                 break;
1538         case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
1539                 return (nd6_setdefaultiface(ndif->ifindex));
1540                 break;
1541         }
1542         return (error);
1543 }
1544
1545 /*
1546  * Create neighbor cache entry and cache link-layer address,
1547  * on reception of inbound ND6 packets. (RS/RA/NS/redirect)
1548  */
1549 struct rtentry *
1550 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr,
1551                  int lladdrlen,
1552                  int type,      /* ICMP6 type */
1553                  int code       /* type dependent information */)
1554 {
1555         struct rtentry *rt = NULL;
1556         struct llinfo_nd6 *ln = NULL;
1557         int is_newentry;
1558         struct sockaddr_dl *sdl = NULL;
1559         int do_update;
1560         int olladdr;
1561         int llchange;
1562         int newstate = 0;
1563
1564         if (!ifp)
1565                 panic("ifp == NULL in nd6_cache_lladdr");
1566         if (!from)
1567                 panic("from == NULL in nd6_cache_lladdr");
1568
1569         /* nothing must be updated for unspecified address */
1570         if (IN6_IS_ADDR_UNSPECIFIED(from))
1571                 return NULL;
1572
1573         /*
1574          * Validation about ifp->if_addrlen and lladdrlen must be done in
1575          * the caller.
1576          *
1577          * XXX If the link does not have link-layer adderss, what should
1578          * we do? (ifp->if_addrlen == 0)
1579          * Spec says nothing in sections for RA, RS and NA.  There's small
1580          * description on it in NS section (RFC 2461 7.2.3).
1581          */
1582
1583         rt = nd6_lookup(from, 0, ifp);
1584         if (!rt) {
1585 #if 0
1586                 /* nothing must be done if there's no lladdr */
1587                 if (!lladdr || !lladdrlen)
1588                         return NULL;
1589 #endif
1590
1591                 rt = nd6_lookup(from, 1, ifp);
1592                 is_newentry = 1;
1593         } else {
1594                 /* do nothing if static ndp is set */
1595                 if (rt->rt_flags & RTF_STATIC)
1596                         return NULL;
1597                 is_newentry = 0;
1598         }
1599
1600         if (!rt)
1601                 return NULL;
1602         if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) {
1603 fail:
1604                 nd6_free(rt);
1605                 return NULL;
1606         }
1607         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1608         if (!ln)
1609                 goto fail;
1610         if (!rt->rt_gateway)
1611                 goto fail;
1612         if (rt->rt_gateway->sa_family != AF_LINK)
1613                 goto fail;
1614         sdl = SDL(rt->rt_gateway);
1615
1616         olladdr = (sdl->sdl_alen) ? 1 : 0;
1617         if (olladdr && lladdr) {
1618                 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
1619                         llchange = 1;
1620                 else
1621                         llchange = 0;
1622         } else
1623                 llchange = 0;
1624
1625         /*
1626          * newentry olladdr  lladdr  llchange   (*=record)
1627          *      0       n       n       --      (1)
1628          *      0       y       n       --      (2)
1629          *      0       n       y       --      (3) * STALE
1630          *      0       y       y       n       (4) *
1631          *      0       y       y       y       (5) * STALE
1632          *      1       --      n       --      (6)   NOSTATE(= PASSIVE)
1633          *      1       --      y       --      (7) * STALE
1634          */
1635
1636         if (lladdr) {           /* (3-5) and (7) */
1637                 /*
1638                  * Record source link-layer address
1639                  * XXX is it dependent to ifp->if_type?
1640                  */
1641                 sdl->sdl_alen = ifp->if_addrlen;
1642                 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
1643         }
1644
1645         if (!is_newentry) {
1646                 if ((!olladdr && lladdr)                /* (3) */
1647                  || (olladdr && lladdr && llchange)) {  /* (5) */
1648                         do_update = 1;
1649                         newstate = ND6_LLINFO_STALE;
1650                 } else                                  /* (1-2,4) */
1651                         do_update = 0;
1652         } else {
1653                 do_update = 1;
1654                 if (!lladdr)                            /* (6) */
1655                         newstate = ND6_LLINFO_NOSTATE;
1656                 else                                    /* (7) */
1657                         newstate = ND6_LLINFO_STALE;
1658         }
1659
1660         if (do_update) {
1661                 /*
1662                  * Update the state of the neighbor cache.
1663                  */
1664                 ln->ln_state = newstate;
1665
1666                 if (ln->ln_state == ND6_LLINFO_STALE) {
1667                         /*
1668                          * XXX: since nd6_output() below will cause
1669                          * state tansition to DELAY and reset the timer,
1670                          * we must set the timer now, although it is actually
1671                          * meaningless.
1672                          */
1673                         ln->ln_expire = time_second + nd6_gctimer;
1674
1675                         if (ln->ln_hold) {
1676                                 /*
1677                                  * we assume ifp is not a p2p here, so just
1678                                  * set the 2nd argument as the 1st one.
1679                                  */
1680                                 nd6_output(ifp, ifp, ln->ln_hold,
1681                                            (struct sockaddr_in6 *)rt_key(rt),
1682                                            rt);
1683                                 ln->ln_hold = NULL;
1684                         }
1685                 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
1686                         /* probe right away */
1687                         ln->ln_expire = time_second;
1688                 }
1689         }
1690
1691         /*
1692          * ICMP6 type dependent behavior.
1693          *
1694          * NS: clear IsRouter if new entry
1695          * RS: clear IsRouter
1696          * RA: set IsRouter if there's lladdr
1697          * redir: clear IsRouter if new entry
1698          *
1699          * RA case, (1):
1700          * The spec says that we must set IsRouter in the following cases:
1701          * - If lladdr exist, set IsRouter.  This means (1-5).
1702          * - If it is old entry (!newentry), set IsRouter.  This means (7).
1703          * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
1704          * A quetion arises for (1) case.  (1) case has no lladdr in the
1705          * neighbor cache, this is similar to (6).
1706          * This case is rare but we figured that we MUST NOT set IsRouter.
1707          *
1708          * newentry olladdr  lladdr  llchange       NS  RS  RA  redir
1709          *                                                      D R
1710          *      0       n       n       --      (1)     c   ?     s
1711          *      0       y       n       --      (2)     c   s     s
1712          *      0       n       y       --      (3)     c   s     s
1713          *      0       y       y       n       (4)     c   s     s
1714          *      0       y       y       y       (5)     c   s     s
1715          *      1       --      n       --      (6) c   c       c s
1716          *      1       --      y       --      (7) c   c   s   c s
1717          *
1718          *                                      (c=clear s=set)
1719          */
1720         switch (type & 0xff) {
1721         case ND_NEIGHBOR_SOLICIT:
1722                 /*
1723                  * New entry must have is_router flag cleared.
1724                  */
1725                 if (is_newentry)        /* (6-7) */
1726                         ln->ln_router = 0;
1727                 break;
1728         case ND_REDIRECT:
1729                 /*
1730                  * If the icmp is a redirect to a better router, always set the
1731                  * is_router flag. Otherwise, if the entry is newly created,
1732                  * clear the flag. [RFC 2461, sec 8.3]
1733                  */
1734                 if (code == ND_REDIRECT_ROUTER)
1735                         ln->ln_router = 1;
1736                 else if (is_newentry) /* (6-7) */
1737                         ln->ln_router = 0;
1738                 break;
1739         case ND_ROUTER_SOLICIT:
1740                 /*
1741                  * is_router flag must always be cleared.
1742                  */
1743                 ln->ln_router = 0;
1744                 break;
1745         case ND_ROUTER_ADVERT:
1746                 /*
1747                  * Mark an entry with lladdr as a router.
1748                  */
1749                 if ((!is_newentry && (olladdr || lladdr))       /* (2-5) */
1750                  || (is_newentry && lladdr)) {                  /* (7) */
1751                         ln->ln_router = 1;
1752                 }
1753                 break;
1754         }
1755
1756         /*
1757          * When the link-layer address of a router changes, select the
1758          * best router again.  In particular, when the neighbor entry is newly
1759          * created, it might affect the selection policy.
1760          * Question: can we restrict the first condition to the "is_newentry"
1761          * case?
1762          * XXX: when we hear an RA from a new router with the link-layer
1763          * address option, defrouter_select() is called twice, since
1764          * defrtrlist_update called the function as well.  However, I believe
1765          * we can compromise the overhead, since it only happens the first
1766          * time.
1767          * XXX: although defrouter_select() should not have a bad effect
1768          * for those are not autoconfigured hosts, we explicitly avoid such
1769          * cases for safety.
1770          */
1771         if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv)
1772                 defrouter_select();
1773
1774         return rt;
1775 }
1776
1777 static void
1778 nd6_slowtimo(void *ignored_arg)
1779 {
1780         struct nd_ifinfo *nd6if;
1781         struct ifnet *ifp;
1782
1783         mtx_lock(&nd6_mtx);
1784         callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
1785                         nd6_slowtimo, NULL);
1786         for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1787                 nd6if = ND_IFINFO(ifp);
1788                 if (nd6if->basereachable && /* already initialized */
1789                     (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
1790                         /*
1791                          * Since reachable time rarely changes by router
1792                          * advertisements, we SHOULD insure that a new random
1793                          * value gets recomputed at least once every few hours.
1794                          * (RFC 2461, 6.3.4)
1795                          */
1796                         nd6if->recalctm = nd6_recalc_reachtm_interval;
1797                         nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
1798                 }
1799         }
1800         mtx_unlock(&nd6_mtx);
1801 }
1802
1803 #define gotoerr(e) { error = (e); goto bad;}
1804
1805 int
1806 nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m,
1807            struct sockaddr_in6 *dst, struct rtentry *rt)
1808 {
1809         struct llinfo_nd6 *ln = NULL;
1810         int error = 0;
1811
1812         if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
1813                 goto sendpkt;
1814
1815         if (nd6_need_cache(ifp) == 0)
1816                 goto sendpkt;
1817
1818         /*
1819          * next hop determination.  This routine is derived from ether_outpout.
1820          */
1821         if (rt != NULL) {
1822                 if (!(rt->rt_flags & RTF_UP)) {
1823                         rt = rtlookup((struct sockaddr *)dst);
1824                         if (rt == NULL)
1825                                 gotoerr(EHOSTUNREACH);
1826                         rt->rt_refcnt--;
1827                         if (rt->rt_ifp != ifp) {
1828                                 /* XXX: loop care? */
1829                                 return nd6_output(ifp, origifp, m, dst, rt);
1830                         }
1831                 }
1832                 if (rt->rt_flags & RTF_GATEWAY) {
1833                         struct sockaddr_in6 *gw6;
1834
1835                         /*
1836                          * We skip link-layer address resolution and NUD
1837                          * if the gateway is not a neighbor from ND point
1838                          * of view, regardless of the value of nd_ifinfo.flags.
1839                          * The second condition is a bit tricky; we skip
1840                          * if the gateway is our own address, which is
1841                          * sometimes used to install a route to a p2p link.
1842                          */
1843                         gw6 = (struct sockaddr_in6 *)rt->rt_gateway;
1844                         if (!nd6_is_addr_neighbor(gw6, ifp) ||
1845                             in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) {
1846                                 /*
1847                                  * We allow this kind of tricky route only
1848                                  * when the outgoing interface is p2p.
1849                                  * XXX: we may need a more generic rule here.
1850                                  */
1851                                 if (!(ifp->if_flags & IFF_POINTOPOINT))
1852                                         gotoerr(EHOSTUNREACH);
1853
1854                                 goto sendpkt;
1855                         }
1856
1857                         if (rt->rt_gwroute == NULL) {
1858                                 rt->rt_gwroute = rtlookup(rt->rt_gateway);
1859                                 if (rt->rt_gwroute == NULL)
1860                                         gotoerr(EHOSTUNREACH);
1861                         } else if (!(rt->rt_gwroute->rt_flags & RTF_UP)) {
1862                                 rtfree(rt->rt_gwroute);
1863                                 rt->rt_gwroute = rtlookup(rt->rt_gateway);
1864                                 if (rt->rt_gwroute == NULL)
1865                                         gotoerr(EHOSTUNREACH);
1866                         }
1867                 }
1868         }
1869
1870         /*
1871          * Address resolution or Neighbor Unreachability Detection
1872          * for the next hop.
1873          * At this point, the destination of the packet must be a unicast
1874          * or an anycast address(i.e. not a multicast).
1875          */
1876
1877         /* Look up the neighbor cache for the nexthop */
1878         if (rt && (rt->rt_flags & RTF_LLINFO))
1879                 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1880         else {
1881                 /*
1882                  * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
1883                  * the condition below is not very efficient.  But we believe
1884                  * it is tolerable, because this should be a rare case.
1885                  */
1886                 if (nd6_is_addr_neighbor(dst, ifp) &&
1887                     (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL)
1888                         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
1889         }
1890         if (!ln || !rt) {
1891                 if (!(ifp->if_flags & IFF_POINTOPOINT) &&
1892                     !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) {
1893                         log(LOG_DEBUG,
1894                             "nd6_output: can't allocate llinfo for %s "
1895                             "(ln=%p, rt=%p)\n",
1896                             ip6_sprintf(&dst->sin6_addr), ln, rt);
1897                         gotoerr(EIO);   /* XXX: good error? */
1898                 }
1899
1900                 goto sendpkt;   /* send anyway */
1901         }
1902
1903         /* We don't have to do link-layer address resolution on a p2p link. */
1904         if ((ifp->if_flags & IFF_POINTOPOINT) &&
1905             ln->ln_state < ND6_LLINFO_REACHABLE) {
1906                 ln->ln_state = ND6_LLINFO_STALE;
1907                 ln->ln_expire = time_second + nd6_gctimer;
1908         }
1909
1910         /*
1911          * The first time we send a packet to a neighbor whose entry is
1912          * STALE, we have to change the state to DELAY and a sets a timer to
1913          * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
1914          * neighbor unreachability detection on expiration.
1915          * (RFC 2461 7.3.3)
1916          */
1917         if (ln->ln_state == ND6_LLINFO_STALE) {
1918                 ln->ln_asked = 0;
1919                 ln->ln_state = ND6_LLINFO_DELAY;
1920                 ln->ln_expire = time_second + nd6_delay;
1921         }
1922
1923         /*
1924          * If the neighbor cache entry has a state other than INCOMPLETE
1925          * (i.e. its link-layer address is already resolved), just
1926          * send the packet.
1927          */
1928         if (ln->ln_state > ND6_LLINFO_INCOMPLETE)
1929                 goto sendpkt;
1930
1931         /*
1932          * There is a neighbor cache entry, but no ethernet address
1933          * response yet.  Replace the held mbuf (if any) with this
1934          * latest one.
1935          *
1936          * This code conforms to the rate-limiting rule described in Section
1937          * 7.2.2 of RFC 2461, because the timer is set correctly after sending
1938          * an NS below.
1939          */
1940         if (ln->ln_state == ND6_LLINFO_NOSTATE)
1941                 ln->ln_state = ND6_LLINFO_INCOMPLETE;
1942         if (ln->ln_hold)
1943                 m_freem(ln->ln_hold);
1944         ln->ln_hold = m;
1945         if (ln->ln_expire) {
1946                 if (ln->ln_asked < nd6_mmaxtries &&
1947                     ln->ln_expire < time_second) {
1948                         ln->ln_asked++;
1949                         ln->ln_expire = time_second +
1950                                 ND_IFINFO(ifp)->retrans / 1000;
1951                         nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0);
1952                 }
1953         }
1954         return (0);
1955
1956 sendpkt:
1957         if (ifp->if_flags & IFF_LOOPBACK)
1958                 error = ifp->if_output(origifp, m, (struct sockaddr *)dst, rt);
1959         else
1960                 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, rt);
1961         return (error);
1962
1963 bad:
1964         m_freem(m);
1965         return (error);
1966 }
1967 #undef gotoerr
1968
1969 int
1970 nd6_need_cache(struct ifnet *ifp)
1971 {
1972         /*
1973          * XXX: we currently do not make neighbor cache on any interface
1974          * other than Ethernet and GIF.
1975          *
1976          * RFC2893 says:
1977          * - unidirectional tunnels needs no ND
1978          */
1979         switch (ifp->if_type) {
1980         case IFT_ETHER:
1981         case IFT_IEEE1394:
1982 #ifdef IFT_L2VLAN
1983         case IFT_L2VLAN:
1984 #endif
1985 #ifdef IFT_IEEE80211
1986         case IFT_IEEE80211:
1987 #endif
1988 #ifdef IFT_CARP
1989         case IFT_CARP:
1990 #endif
1991         case IFT_GIF:           /* XXX need more cases? */
1992                 return (1);
1993         default:
1994                 return (0);
1995         }
1996 }
1997
1998 int
1999 nd6_storelladdr(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
2000                 struct sockaddr *dst, u_char *desten)
2001 {
2002         struct sockaddr_dl *sdl;
2003         struct rtentry *rt;
2004
2005
2006         if (m->m_flags & M_MCAST) {
2007                 switch (ifp->if_type) {
2008                 case IFT_ETHER:
2009 #ifdef IFT_L2VLAN
2010         case IFT_L2VLAN:
2011 #endif
2012 #ifdef IFT_IEEE80211
2013                 case IFT_IEEE80211:
2014 #endif
2015                         ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr,
2016                                                  desten);
2017                         return (1);
2018                 case IFT_IEEE1394:
2019                         bcopy(ifp->if_broadcastaddr, desten, ifp->if_addrlen);
2020                         return (1);
2021                 default:
2022                         m_freem(m);
2023                         return (0);
2024                 }
2025         }
2026         if (rt0 == NULL) {
2027                 /* this could happen, if we could not allocate memory */
2028                 m_freem(m);
2029                 return (0);
2030         }
2031         if (rt_llroute(dst, rt0, &rt) != 0) {
2032                 m_freem(m);
2033                 return (0);
2034         }
2035         if (rt->rt_gateway->sa_family != AF_LINK) {
2036                 kprintf("nd6_storelladdr: something odd happens\n");
2037                 m_freem(m);
2038                 return (0);
2039         }
2040         sdl = SDL(rt->rt_gateway);
2041         if (sdl->sdl_alen == 0) {
2042                 /* this should be impossible, but we bark here for debugging */
2043                 kprintf("nd6_storelladdr: sdl_alen == 0\n");
2044                 m_freem(m);
2045                 return (0);
2046         }
2047
2048         bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
2049         return (1);
2050 }
2051
2052 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
2053 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
2054 #ifdef SYSCTL_DECL
2055 SYSCTL_DECL(_net_inet6_icmp6);
2056 #endif
2057 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
2058         CTLFLAG_RD, nd6_sysctl_drlist, "List default routers");
2059 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
2060         CTLFLAG_RD, nd6_sysctl_prlist, "List prefixes");
2061
2062 static int
2063 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
2064 {
2065         int error;
2066         char buf[1024];
2067         struct in6_defrouter *d, *de;
2068         struct nd_defrouter *dr;
2069
2070         if (req->newptr)
2071                 return EPERM;
2072         error = 0;
2073
2074         for (dr = TAILQ_FIRST(&nd_defrouter);
2075              dr;
2076              dr = TAILQ_NEXT(dr, dr_entry)) {
2077                 d = (struct in6_defrouter *)buf;
2078                 de = (struct in6_defrouter *)(buf + sizeof(buf));
2079
2080                 if (d + 1 <= de) {
2081                         bzero(d, sizeof(*d));
2082                         d->rtaddr.sin6_family = AF_INET6;
2083                         d->rtaddr.sin6_len = sizeof(d->rtaddr);
2084                         if (in6_recoverscope(&d->rtaddr, &dr->rtaddr,
2085                             dr->ifp) != 0)
2086                                 log(LOG_ERR,
2087                                     "scope error in "
2088                                     "default router list (%s)\n",
2089                                     ip6_sprintf(&dr->rtaddr));
2090                         d->flags = dr->flags;
2091                         d->rtlifetime = dr->rtlifetime;
2092                         d->expire = dr->expire;
2093                         d->if_index = dr->ifp->if_index;
2094                 } else
2095                         panic("buffer too short");
2096
2097                 error = SYSCTL_OUT(req, buf, sizeof(*d));
2098                 if (error)
2099                         break;
2100         }
2101         return error;
2102 }
2103
2104 static int
2105 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
2106 {
2107         int error;
2108         char buf[1024];
2109         struct in6_prefix *p, *pe;
2110         struct nd_prefix *pr;
2111
2112         if (req->newptr)
2113                 return EPERM;
2114         error = 0;
2115
2116         for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
2117                 u_short advrtrs;
2118                 size_t advance;
2119                 struct sockaddr_in6 *sin6, *s6;
2120                 struct nd_pfxrouter *pfr;
2121
2122                 p = (struct in6_prefix *)buf;
2123                 pe = (struct in6_prefix *)(buf + sizeof(buf));
2124
2125                 if (p + 1 <= pe) {
2126                         bzero(p, sizeof(*p));
2127                         sin6 = (struct sockaddr_in6 *)(p + 1);
2128
2129                         p->prefix = pr->ndpr_prefix;
2130                         if (in6_recoverscope(&p->prefix,
2131                             &p->prefix.sin6_addr, pr->ndpr_ifp) != 0)
2132                                 log(LOG_ERR,
2133                                     "scope error in prefix list (%s)\n",
2134                                     ip6_sprintf(&p->prefix.sin6_addr));
2135                         p->raflags = pr->ndpr_raf;
2136                         p->prefixlen = pr->ndpr_plen;
2137                         p->vltime = pr->ndpr_vltime;
2138                         p->pltime = pr->ndpr_pltime;
2139                         p->if_index = pr->ndpr_ifp->if_index;
2140                         p->expire = pr->ndpr_expire;
2141                         p->refcnt = pr->ndpr_refcnt;
2142                         p->flags = pr->ndpr_stateflags;
2143                         p->origin = PR_ORIG_RA;
2144                         advrtrs = 0;
2145                         for (pfr = pr->ndpr_advrtrs.lh_first;
2146                              pfr;
2147                              pfr = pfr->pfr_next) {
2148                                 if ((void *)&sin6[advrtrs + 1] >
2149                                     (void *)pe) {
2150                                         advrtrs++;
2151                                         continue;
2152                                 }
2153                                 s6 = &sin6[advrtrs];
2154                                 bzero(s6, sizeof(*s6));
2155                                 s6->sin6_family = AF_INET6;
2156                                 s6->sin6_len = sizeof(*sin6);
2157                                 if (in6_recoverscope(s6, &pfr->router->rtaddr,
2158                                                      pfr->router->ifp) != 0)
2159                                         log(LOG_ERR,
2160                                             "scope error in "
2161                                             "prefix list (%s)\n",
2162                                             ip6_sprintf(&pfr->router->rtaddr));
2163                                 advrtrs++;
2164                         }
2165                         p->advrtrs = advrtrs;
2166                 } else
2167                         panic("buffer too short");
2168
2169                 advance = sizeof(*p) + sizeof(*sin6) * advrtrs;
2170                 error = SYSCTL_OUT(req, buf, advance);
2171                 if (error)
2172                         break;
2173         }
2174         return error;
2175 }