sys/netinet6/icmp6.c

   1 /*      $FreeBSD: src/sys/netinet6/icmp6.c,v 1.6.2.13 2003/05/06 06:46:58 suz Exp $     */
   2 /*      $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 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  * Copyright (c) 1982, 1986, 1988, 1993
  35  *      The Regents of the University of California.  All rights reserved.
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  * 3. Neither the name of the University nor the names of its contributors
  46  *    may be used to endorse or promote products derived from this software
  47  *    without specific prior written permission.
  48  *
  49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  59  * SUCH DAMAGE.
  60  *
  61  *      @(#)ip_icmp.c   8.2 (Berkeley) 1/4/94
  62  */
  63
  64 #include "opt_inet.h"
  65 #include "opt_inet6.h"
  66 #include "opt_ipsec.h"
  67
  68 #include <sys/param.h>
  69 #include <sys/systm.h>
  70 #include <sys/malloc.h>
  71 #include <sys/mbuf.h>
  72 #include <sys/protosw.h>
  73 #include <sys/socket.h>
  74 #include <sys/socketvar.h>
  75 #include <sys/socketops.h>
  76 #include <sys/time.h>
  77 #include <sys/kernel.h>
  78 #include <sys/syslog.h>
  79 #include <sys/domain.h>
  80
  81 #include <sys/thread2.h>
  82 #include <sys/msgport2.h>
  83
  84 #include <net/if.h>
  85 #include <net/route.h>
  86 #include <net/if_dl.h>
  87 #include <net/if_types.h>
  88
  89 #include <netinet/in.h>
  90 #include <netinet/in_var.h>
  91 #include <netinet/ip6.h>
  92 #include <netinet6/ip6_var.h>
  93 #include <netinet/icmp6.h>
  94 #include <netinet6/mld6_var.h>
  95 #include <netinet/in_pcb.h>
  96 #include <netinet6/in6_pcb.h>
  97 #include <netinet6/nd6.h>
  98 #include <netinet6/in6_ifattach.h>
  99 #include <netinet6/ip6protosw.h>
 100
 101 #ifdef IPSEC
 102 #include <netinet6/ipsec.h>
 103 #include <netproto/key/key.h>
 104 #endif
 105
 106 #ifdef FAST_IPSEC
 107 #include <netproto/ipsec/ipsec.h>
 108 #include <netproto/ipsec/key.h>
 109 #define IPSEC
 110 #endif
 111
 112 #include <net/net_osdep.h>
 113
 114 #ifdef HAVE_NRL_INPCB
 115 /* inpcb members */
 116 #define in6pcb          inpcb
 117 #define in6p_laddr      inp_laddr6
 118 #define in6p_faddr      inp_faddr6
 119 #define in6p_icmp6filt  inp_icmp6filt
 120 #define in6p_route      inp_route
 121 #define in6p_socket     inp_socket
 122 #define in6p_flags      inp_flags
 123 #define in6p_moptions   inp_moptions6
 124 #define in6p_outputopts inp_outputopts6
 125 #define in6p_ip6        inp_ipv6
 126 #define in6p_flowinfo   inp_flowinfo
 127 #define in6p_sp         inp_sp
 128 #define in6p_next       inp_next
 129 #define in6p_prev       inp_prev
 130 /* function names */
 131 #define in6_pcbdetach   in_pcbdetach
 132 #define in6_rtchange    in_rtchange
 133
 134 /*
 135  * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from
 136  * others...
 137  */
 138 #define in6p_ip6_nxt    inp_ipv6.ip6_nxt
 139 #endif
 140
 141 /*
 142  * ppratecheck() is available, so define it here.
 143  */
 144 #define HAVE_PPSRATECHECK
 145
 146 extern struct domain inet6domain;
 147 extern struct protosw inet6sw[];
 148 extern u_char ip6_protox[];
 149
 150 struct icmp6stat icmp6stat;
 151
 152 extern struct inpcbinfo ripcbinfo;
 153 extern int icmp6errppslim;
 154 static int icmp6errpps_count = 0;
 155 static struct timeval icmp6errppslim_last;
 156 extern int icmp6_nodeinfo;
 157
 158 static void icmp6_errcount (struct icmp6errstat *, int, int);
 159 static int icmp6_rip6_input (struct mbuf **, int);
 160 static int icmp6_ratelimit (const struct in6_addr *, const int, const int);
 161 static const char *icmp6_redirect_diag (struct in6_addr *,
 162         struct in6_addr *, struct in6_addr *);
 163 #ifndef HAVE_PPSRATECHECK
 164 static int ppsratecheck (struct timeval *, int *, int);
 165 #endif
 166 static struct mbuf *ni6_input (struct mbuf *, int);
 167 static struct mbuf *ni6_nametodns (const char *, int, int);
 168 static int ni6_dnsmatch (const char *, int, const char *, int);
 169 static int ni6_addrs (struct icmp6_nodeinfo *, struct mbuf *,
 170                           struct ifnet **, char *);
 171 static int ni6_store_addrs (struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
 172                                 struct ifnet *, int);
 173 static int icmp6_notify_error (struct mbuf *, int, int, int);
 174
 175 #ifdef COMPAT_RFC1885
 176 static struct route_in6 icmp6_reflect_rt;
 177 #endif
 178
 179
 180 void
 181 icmp6_init(void)
 182 {
 183         mld6_init();
 184 }
 185
 186 static void
 187 icmp6_errcount(struct icmp6errstat *stat, int type, int code)
 188 {
 189         switch (type) {
 190         case ICMP6_DST_UNREACH:
 191                 switch (code) {
 192                 case ICMP6_DST_UNREACH_NOROUTE:
 193                         stat->icp6errs_dst_unreach_noroute++;
 194                         return;
 195                 case ICMP6_DST_UNREACH_ADMIN:
 196                         stat->icp6errs_dst_unreach_admin++;
 197                         return;
 198                 case ICMP6_DST_UNREACH_BEYONDSCOPE:
 199                         stat->icp6errs_dst_unreach_beyondscope++;
 200                         return;
 201                 case ICMP6_DST_UNREACH_ADDR:
 202                         stat->icp6errs_dst_unreach_addr++;
 203                         return;
 204                 case ICMP6_DST_UNREACH_NOPORT:
 205                         stat->icp6errs_dst_unreach_noport++;
 206                         return;
 207                 }
 208                 break;
 209         case ICMP6_PACKET_TOO_BIG:
 210                 stat->icp6errs_packet_too_big++;
 211                 return;
 212         case ICMP6_TIME_EXCEEDED:
 213                 switch (code) {
 214                 case ICMP6_TIME_EXCEED_TRANSIT:
 215                         stat->icp6errs_time_exceed_transit++;
 216                         return;
 217                 case ICMP6_TIME_EXCEED_REASSEMBLY:
 218                         stat->icp6errs_time_exceed_reassembly++;
 219                         return;
 220                 }
 221                 break;
 222         case ICMP6_PARAM_PROB:
 223                 switch (code) {
 224                 case ICMP6_PARAMPROB_HEADER:
 225                         stat->icp6errs_paramprob_header++;
 226                         return;
 227                 case ICMP6_PARAMPROB_NEXTHEADER:
 228                         stat->icp6errs_paramprob_nextheader++;
 229                         return;
 230                 case ICMP6_PARAMPROB_OPTION:
 231                         stat->icp6errs_paramprob_option++;
 232                         return;
 233                 }
 234                 break;
 235         case ND_REDIRECT:
 236                 stat->icp6errs_redirect++;
 237                 return;
 238         }
 239         stat->icp6errs_unknown++;
 240 }
 241
 242 /*
 243  * Generate an error packet of type error in response to bad IP6 packet.
 244  */
 245 void
 246 icmp6_error(struct mbuf *m, int type, int code, int param)
 247 {
 248         struct ip6_hdr *oip6, *nip6;
 249         struct icmp6_hdr *icmp6;
 250         u_int preplen;
 251         int off;
 252         int nxt;
 253
 254         icmp6stat.icp6s_error++;
 255
 256         /* count per-type-code statistics */
 257         icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code);
 258
 259 #ifdef M_DECRYPTED      /*not openbsd*/
 260         if (m->m_flags & M_DECRYPTED) {
 261                 icmp6stat.icp6s_canterror++;
 262                 goto freeit;
 263         }
 264 #endif
 265
 266 #ifndef PULLDOWN_TEST
 267         IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
 268 #else
 269         if (m->m_len < sizeof(struct ip6_hdr)) {
 270                 m = m_pullup(m, sizeof(struct ip6_hdr));
 271                 if (m == NULL)
 272                         return;
 273         }
 274 #endif
 275         oip6 = mtod(m, struct ip6_hdr *);
 276
 277         /*
 278          * Multicast destination check. For unrecognized option errors,
 279          * this check has already done in ip6_unknown_opt(), so we can
 280          * check only for other errors.
 281          */
 282         if ((m->m_flags & (M_BCAST|M_MCAST) ||
 283              IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
 284             (type != ICMP6_PACKET_TOO_BIG &&
 285              (type != ICMP6_PARAM_PROB ||
 286               code != ICMP6_PARAMPROB_OPTION)))
 287                 goto freeit;
 288
 289         /* Source address check. XXX: the case of anycast source? */
 290         if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
 291             IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
 292                 goto freeit;
 293
 294         /*
 295          * If we are about to send ICMPv6 against ICMPv6 error/redirect,
 296          * don't do it.
 297          */
 298         nxt = -1;
 299         off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
 300         if (off >= 0 && nxt == IPPROTO_ICMPV6) {
 301                 struct icmp6_hdr *icp;
 302
 303 #ifndef PULLDOWN_TEST
 304                 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
 305                 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
 306 #else
 307                 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
 308                         sizeof(*icp));
 309                 if (icp == NULL) {
 310                         icmp6stat.icp6s_tooshort++;
 311                         return;
 312                 }
 313 #endif
 314                 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
 315                     icp->icmp6_type == ND_REDIRECT) {
 316                         /*
 317                          * ICMPv6 error
 318                          * Special case: for redirect (which is
 319                          * informational) we must not send icmp6 error.
 320                          */
 321                         icmp6stat.icp6s_canterror++;
 322                         goto freeit;
 323                 } else {
 324                         /* ICMPv6 informational - send the error */
 325                 }
 326         } else {
 327                 /* non-ICMPv6 - send the error */
 328         }
 329
 330         oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
 331
 332         /* Finally, do rate limitation check. */
 333         if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
 334                 icmp6stat.icp6s_toofreq++;
 335                 goto freeit;
 336         }
 337
 338         /*
 339          * OK, ICMP6 can be generated.
 340          */
 341
 342         if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
 343                 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
 344
 345         preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
 346         M_PREPEND(m, preplen, M_NOWAIT);
 347         if (m && m->m_len < preplen)
 348                 m = m_pullup(m, preplen);
 349         if (m == NULL) {
 350                 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
 351                 return;
 352         }
 353
 354         nip6 = mtod(m, struct ip6_hdr *);
 355         nip6->ip6_src  = oip6->ip6_src;
 356         nip6->ip6_dst  = oip6->ip6_dst;
 357
 358         in6_clearscope(&oip6->ip6_src);
 359         in6_clearscope(&oip6->ip6_dst);
 360
 361         icmp6 = (struct icmp6_hdr *)(nip6 + 1);
 362         icmp6->icmp6_type = type;
 363         icmp6->icmp6_code = code;
 364         icmp6->icmp6_pptr = htonl((u_int32_t)param);
 365
 366         /*
 367          * icmp6_reflect() is designed to be in the input path.
 368          * icmp6_error() can be called from both input and outut path,
 369          * and if we are in output path rcvif could contain bogus value.
 370          * clear m->m_pkthdr.rcvif for safety, we should have enough scope
 371          * information in ip header (nip6).
 372          */
 373         m->m_pkthdr.rcvif = NULL;
 374
 375         icmp6stat.icp6s_outhist[type]++;
 376         icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
 377
 378         return;
 379
 380 freeit:
 381         /*
 382          * If we can't tell wheter or not we can generate ICMP6, free it.
 383          */
 384         m_freem(m);
 385 }
 386
 387 /*
 388  * Process a received ICMP6 message.
 389  */
 390 int
 391 icmp6_input(struct mbuf **mp, int *offp, int proto)
 392 {
 393         struct mbuf *m = *mp, *n;
 394         struct ip6_hdr *ip6, *nip6;
 395         struct icmp6_hdr *icmp6, *nicmp6;
 396         int off = *offp;
 397         int icmp6len = m->m_pkthdr.len - *offp;
 398         int code, sum, noff;
 399
 400 #ifndef PULLDOWN_TEST
 401         IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
 402         /* m might change if M_LOOP.  So, call mtod after this */
 403 #endif
 404
 405         /*
 406          * Locate icmp6 structure in mbuf, and check
 407          * that not corrupted and of at least minimum length
 408          */
 409
 410         ip6 = mtod(m, struct ip6_hdr *);
 411         if (icmp6len < sizeof(struct icmp6_hdr)) {
 412                 icmp6stat.icp6s_tooshort++;
 413                 goto freeit;
 414         }
 415
 416         /*
 417          * calculate the checksum
 418          */
 419 #ifndef PULLDOWN_TEST
 420         icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
 421 #else
 422         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
 423         if (icmp6 == NULL) {
 424                 icmp6stat.icp6s_tooshort++;
 425                 return IPPROTO_DONE;
 426         }
 427 #endif
 428         code = icmp6->icmp6_code;
 429
 430         if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
 431                 nd6log((LOG_ERR,
 432                     "ICMP6 checksum error(%d|%x) %s\n",
 433                     icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src)));
 434                 icmp6stat.icp6s_checksum++;
 435                 goto freeit;
 436         }
 437
 438         if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
 439                 /*
 440                  * Deliver very specific ICMP6 type only.
 441                  * This is important to deilver TOOBIG.  Otherwise PMTUD
 442                  * will not work.
 443                  */
 444                 switch (icmp6->icmp6_type) {
 445                 case ICMP6_DST_UNREACH:
 446                 case ICMP6_PACKET_TOO_BIG:
 447                 case ICMP6_TIME_EXCEEDED:
 448                         break;
 449                 default:
 450                         goto freeit;
 451                 }
 452         }
 453
 454         icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
 455         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
 456         if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
 457                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
 458
 459         switch (icmp6->icmp6_type) {
 460         case ICMP6_DST_UNREACH:
 461                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
 462                 switch (code) {
 463                 case ICMP6_DST_UNREACH_NOROUTE:
 464                         code = PRC_UNREACH_NET;
 465                         break;
 466                 case ICMP6_DST_UNREACH_ADMIN:
 467                         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
 468                         code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
 469                         break;
 470                 case ICMP6_DST_UNREACH_ADDR:
 471                         code = PRC_HOSTDEAD;
 472                         break;
 473 #ifdef COMPAT_RFC1885
 474                 case ICMP6_DST_UNREACH_NOTNEIGHBOR:
 475                         code = PRC_UNREACH_SRCFAIL;
 476                         break;
 477 #else
 478                 case ICMP6_DST_UNREACH_BEYONDSCOPE:
 479                         /* I mean "source address was incorrect." */
 480                         code = PRC_PARAMPROB;
 481                         break;
 482 #endif
 483                 case ICMP6_DST_UNREACH_NOPORT:
 484                         code = PRC_UNREACH_PORT;
 485                         break;
 486                 default:
 487                         goto badcode;
 488                 }
 489                 goto deliver;
 490                 break;
 491
 492         case ICMP6_PACKET_TOO_BIG:
 493                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
 494                 if (code != 0)
 495                         goto badcode;
 496
 497                 code = PRC_MSGSIZE;
 498
 499                 /*
 500                  * Updating the path MTU will be done after examining
 501                  * intermediate extension headers.
 502                  */
 503                 goto deliver;
 504                 break;
 505
 506         case ICMP6_TIME_EXCEEDED:
 507                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
 508                 switch (code) {
 509                 case ICMP6_TIME_EXCEED_TRANSIT:
 510                 case ICMP6_TIME_EXCEED_REASSEMBLY:
 511                         code += PRC_TIMXCEED_INTRANS;
 512                         break;
 513                 default:
 514                         goto badcode;
 515                 }
 516                 goto deliver;
 517                 break;
 518
 519         case ICMP6_PARAM_PROB:
 520                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
 521                 switch (code) {
 522                 case ICMP6_PARAMPROB_NEXTHEADER:
 523                         code = PRC_UNREACH_PROTOCOL;
 524                         break;
 525                 case ICMP6_PARAMPROB_HEADER:
 526                 case ICMP6_PARAMPROB_OPTION:
 527                         code = PRC_PARAMPROB;
 528                         break;
 529                 default:
 530                         goto badcode;
 531                 }
 532                 goto deliver;
 533                 break;
 534
 535         case ICMP6_ECHO_REQUEST:
 536                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
 537                 if (code != 0)
 538                         goto badcode;
 539                 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
 540                         /* Give up remote */
 541                         break;
 542                 }
 543                 if ((n->m_flags & M_EXT) ||
 544                     n->m_len < off + sizeof(struct icmp6_hdr)) {
 545                         struct mbuf *n0 = n;
 546                         const int maxlen = sizeof(*nip6) + sizeof(*nicmp6);
 547                         int n0len;
 548
 549                         /*
 550                          * Prepare an internal mbuf. m_pullup() doesn't
 551                          * always copy the length we specified.
 552                          */
 553                         if (maxlen >= MCLBYTES) {
 554                                 /* Give up remote */
 555                                 m_freem(n0);
 556                                 break;
 557                         }
 558                         n = m_getb(maxlen, M_NOWAIT, n0->m_type, M_PKTHDR);
 559                         if (n == NULL) {
 560                                 /* Give up remote */
 561                                 m_freem(n0);
 562                                 break;
 563                         }
 564                         n0len = n0->m_pkthdr.len;       /* save for use below */
 565                         M_MOVE_PKTHDR(n, n0);
 566                         /*
 567                          * Copy IPv6 and ICMPv6 only.
 568                          */
 569                         nip6 = mtod(n, struct ip6_hdr *);
 570                         bcopy(ip6, nip6, sizeof(struct ip6_hdr));
 571                         nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
 572                         bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
 573                         noff = sizeof(struct ip6_hdr);
 574                         /* new mbuf contains only ipv6+icmpv6 headers */
 575                         n->m_len = noff + sizeof(struct icmp6_hdr);
 576                         /*
 577                          * Adjust mbuf. ip6_plen will be adjusted in
 578                          * ip6_output().
 579                          */
 580                         m_adj(n0, off + sizeof(struct icmp6_hdr));
 581                         /* recalculate complete packet size */
 582                         n->m_pkthdr.len = n0len + (noff - off);
 583                         n->m_next = n0;
 584                 } else {
 585                         nip6 = mtod(n, struct ip6_hdr *);
 586                         nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off);
 587                         noff = off;
 588                 }
 589                 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
 590                 nicmp6->icmp6_code = 0;
 591                 if (n) {
 592                         icmp6stat.icp6s_reflect++;
 593                         icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
 594                         icmp6_reflect(n, noff);
 595                 }
 596                 break;
 597
 598         case ICMP6_ECHO_REPLY:
 599                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
 600                 if (code != 0)
 601                         goto badcode;
 602                 break;
 603
 604         case MLD_LISTENER_QUERY:
 605         case MLD_LISTENER_REPORT:
 606                 if (icmp6len < sizeof(struct mld_hdr))
 607                         goto badlen;
 608                 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */
 609                         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
 610                 else
 611                         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
 612                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 613                         /* give up local */
 614                         mld6_input(m, off);
 615                         m = NULL;
 616                         goto freeit;
 617                 }
 618                 mld6_input(n, off);
 619                 /* m stays. */
 620                 break;
 621
 622         case MLD_LISTENER_DONE:
 623                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
 624                 if (icmp6len < sizeof(struct mld_hdr))  /* necessary? */
 625                         goto badlen;
 626                 break;          /* nothing to be done in kernel */
 627
 628         case MLD_MTRACE_RESP:
 629         case MLD_MTRACE:
 630                 /* XXX: these two are experimental.  not officially defind. */
 631                 /* XXX: per-interface statistics? */
 632                 break;          /* just pass it to applications */
 633
 634         case ICMP6_WRUREQUEST:  /* ICMP6_FQDN_QUERY */
 635             {
 636                 enum { WRU, FQDN } mode;
 637
 638                 if (!icmp6_nodeinfo)
 639                         break;
 640
 641                 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
 642                         mode = WRU;
 643                 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
 644                         mode = FQDN;
 645                 else
 646                         goto badlen;
 647
 648 #define hostnamelen     strlen(hostname)
 649                 if (mode == FQDN) {
 650 #ifndef PULLDOWN_TEST
 651                         IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
 652                                          IPPROTO_DONE);
 653 #endif
 654                         n = m_copy(m, 0, M_COPYALL);
 655                         if (n)
 656                                 n = ni6_input(n, off);
 657                         /* XXX meaningless if n == NULL */
 658                         noff = sizeof(struct ip6_hdr);
 659                 } else {
 660                         u_char *p;
 661                         int maxlen, maxhlen;
 662
 663                         if ((icmp6_nodeinfo & 5) != 5)
 664                                 break;
 665
 666                         if (code != 0)
 667                                 goto badcode;
 668                         maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
 669                         if (maxlen >= MCLBYTES) {
 670                                 /* Give up remote */
 671                                 break;
 672                         }
 673                         n = m_getb(maxlen, M_NOWAIT, m->m_type, M_PKTHDR);
 674                         if (n == NULL) {
 675                                 /* Give up remote */
 676                                 break;
 677                         }
 678                         if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
 679                                 /*
 680                                  * Previous code did a blind M_COPY_PKTHDR
 681                                  * and said "just for rcvif".  If true, then
 682                                  * we could tolerate the dup failing (due to
 683                                  * the deep copy of the tag chain).  For now
 684                                  * be conservative and just fail.
 685                                  */
 686                                 m_free(n);
 687                                 break;
 688                         }
 689                         n->m_len = 0;
 690                         maxhlen = M_TRAILINGSPACE(n) - maxlen;
 691                         if (maxhlen > hostnamelen)
 692                                 maxhlen = hostnamelen;
 693                         /*
 694                          * Copy IPv6 and ICMPv6 only.
 695                          */
 696                         nip6 = mtod(n, struct ip6_hdr *);
 697                         bcopy(ip6, nip6, sizeof(struct ip6_hdr));
 698                         nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
 699                         bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
 700                         p = (u_char *)(nicmp6 + 1);
 701                         bzero(p, 4);
 702                         bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */
 703                         noff = sizeof(struct ip6_hdr);
 704                         n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
 705                                 sizeof(struct icmp6_hdr) + 4 + maxhlen;
 706                         nicmp6->icmp6_type = ICMP6_WRUREPLY;
 707                         nicmp6->icmp6_code = 0;
 708                 }
 709 #undef hostnamelen
 710                 if (n) {
 711                         icmp6stat.icp6s_reflect++;
 712                         icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
 713                         icmp6_reflect(n, noff);
 714                 }
 715                 break;
 716             }
 717
 718         case ICMP6_WRUREPLY:
 719                 if (code != 0)
 720                         goto badcode;
 721                 break;
 722
 723         case ND_ROUTER_SOLICIT:
 724                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
 725                 if (code != 0)
 726                         goto badcode;
 727                 if (icmp6len < sizeof(struct nd_router_solicit))
 728                         goto badlen;
 729                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 730                         /* give up local */
 731                         nd6_rs_input(m, off, icmp6len);
 732                         m = NULL;
 733                         goto freeit;
 734                 }
 735                 nd6_rs_input(n, off, icmp6len);
 736                 /* m stays. */
 737                 break;
 738
 739         case ND_ROUTER_ADVERT:
 740                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
 741                 if (code != 0)
 742                         goto badcode;
 743                 if (icmp6len < sizeof(struct nd_router_advert))
 744                         goto badlen;
 745                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 746                         /* give up local */
 747                         nd6_ra_input(m, off, icmp6len);
 748                         m = NULL;
 749                         goto freeit;
 750                 }
 751                 nd6_ra_input(n, off, icmp6len);
 752                 /* m stays. */
 753                 break;
 754
 755         case ND_NEIGHBOR_SOLICIT:
 756                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
 757                 if (code != 0)
 758                         goto badcode;
 759                 if (icmp6len < sizeof(struct nd_neighbor_solicit))
 760                         goto badlen;
 761                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 762                         /* give up local */
 763                         nd6_ns_input(m, off, icmp6len);
 764                         m = NULL;
 765                         goto freeit;
 766                 }
 767                 nd6_ns_input(n, off, icmp6len);
 768                 /* m stays. */
 769                 break;
 770
 771         case ND_NEIGHBOR_ADVERT:
 772                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
 773                 if (code != 0)
 774                         goto badcode;
 775                 if (icmp6len < sizeof(struct nd_neighbor_advert))
 776                         goto badlen;
 777                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 778                         /* give up local */
 779                         nd6_na_input(m, off, icmp6len);
 780                         m = NULL;
 781                         goto freeit;
 782                 }
 783                 nd6_na_input(n, off, icmp6len);
 784                 /* m stays. */
 785                 break;
 786
 787         case ND_REDIRECT:
 788                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
 789                 if (code != 0)
 790                         goto badcode;
 791                 if (icmp6len < sizeof(struct nd_redirect))
 792                         goto badlen;
 793                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 794                         /* give up local */
 795                         icmp6_redirect_input(m, off);
 796                         m = NULL;
 797                         goto freeit;
 798                 }
 799                 icmp6_redirect_input(n, off);
 800                 /* m stays. */
 801                 break;
 802
 803         case ICMP6_ROUTER_RENUMBERING:
 804                 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
 805                     code != ICMP6_ROUTER_RENUMBERING_RESULT)
 806                         goto badcode;
 807                 if (icmp6len < sizeof(struct icmp6_router_renum))
 808                         goto badlen;
 809                 break;
 810
 811         default:
 812                 nd6log((LOG_DEBUG,
 813                     "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
 814                     icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
 815                     ip6_sprintf(&ip6->ip6_dst),
 816                     m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0));
 817                 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
 818                         /* ICMPv6 error: MUST deliver it by spec... */
 819                         code = PRC_NCMDS;
 820                         /* deliver */
 821                 } else {
 822                         /* ICMPv6 informational: MUST not deliver */
 823                         break;
 824                 }
 825         deliver:
 826                 if (icmp6_notify_error(m, off, icmp6len, code)) {
 827                         /* In this case, m should've been freed. */
 828                         return (IPPROTO_DONE);
 829                 }
 830                 break;
 831
 832         badcode:
 833                 icmp6stat.icp6s_badcode++;
 834                 break;
 835
 836         badlen:
 837                 icmp6stat.icp6s_badlen++;
 838                 break;
 839         }
 840
 841         /* deliver the packet to appropriate sockets */
 842         icmp6_rip6_input(&m, *offp);
 843
 844         return IPPROTO_DONE;
 845
 846 freeit:
 847         m_freem(m);
 848         return IPPROTO_DONE;
 849 }
 850
 851 static int
 852 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code)
 853 {
 854         struct icmp6_hdr *icmp6;
 855         struct ip6_hdr *eip6;
 856         u_int32_t notifymtu;
 857         struct sockaddr_in6 icmp6src, icmp6dst;
 858
 859         if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
 860                 icmp6stat.icp6s_tooshort++;
 861                 goto freeit;
 862         }
 863 #ifndef PULLDOWN_TEST
 864         IP6_EXTHDR_CHECK(m, off,
 865                          sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
 866                          -1);
 867         icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
 868 #else
 869         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
 870                        sizeof(*icmp6) + sizeof(struct ip6_hdr));
 871         if (icmp6 == NULL) {
 872                 icmp6stat.icp6s_tooshort++;
 873                 return (-1);
 874         }
 875 #endif
 876         eip6 = (struct ip6_hdr *)(icmp6 + 1);
 877
 878         /* Detect the upper level protocol */
 879         {
 880                 u_int8_t nxt = eip6->ip6_nxt;
 881                 int eoff = off + sizeof(struct icmp6_hdr) +
 882                         sizeof(struct ip6_hdr);
 883                 struct ip6ctlparam ip6cp;
 884                 struct in6_addr *finaldst = NULL;
 885                 int icmp6type = icmp6->icmp6_type;
 886                 struct ip6_frag *fh;
 887                 struct ip6_rthdr *rth;
 888                 int rthlen;
 889
 890                 while (1) { /* XXX: should avoid infinite loop explicitly? */
 891                         struct ip6_ext *eh;
 892
 893                         switch (nxt) {
 894                         case IPPROTO_HOPOPTS:
 895                         case IPPROTO_DSTOPTS:
 896                         case IPPROTO_AH:
 897 #ifndef PULLDOWN_TEST
 898                                 IP6_EXTHDR_CHECK(m, 0,
 899                                     eoff + sizeof(struct ip6_ext), -1);
 900                                 eh = (struct ip6_ext *)
 901                                     (mtod(m, caddr_t) + eoff);
 902 #else
 903                                 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
 904                                                eoff, sizeof(*eh));
 905                                 if (eh == NULL) {
 906                                         icmp6stat.icp6s_tooshort++;
 907                                         return (-1);
 908                                 }
 909 #endif
 910
 911                                 if (nxt == IPPROTO_AH)
 912                                         eoff += (eh->ip6e_len + 2) << 2;
 913                                 else
 914                                         eoff += (eh->ip6e_len + 1) << 3;
 915                                 nxt = eh->ip6e_nxt;
 916                                 break;
 917                         case IPPROTO_ROUTING:
 918                                 /*
 919                                  * When the erroneous packet contains a
 920                                  * routing header, we should examine the
 921                                  * header to determine the final destination.
 922                                  * Otherwise, we can't properly update
 923                                  * information that depends on the final
 924                                  * destination (e.g. path MTU).
 925                                  */
 926 #ifndef PULLDOWN_TEST
 927                                 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth),
 928                                                  -1);
 929                                 rth = (struct ip6_rthdr *)(mtod(m, caddr_t)
 930                                                            + eoff);
 931 #else
 932                                 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
 933                                                eoff, sizeof(*rth));
 934                                 if (rth == NULL) {
 935                                         icmp6stat.icp6s_tooshort++;
 936                                         return (-1);
 937                                 }
 938 #endif
 939                                 rthlen = (rth->ip6r_len + 1) << 3;
 940                                 eoff += rthlen;
 941                                 nxt = rth->ip6r_nxt;
 942                                 break;
 943                         case IPPROTO_FRAGMENT:
 944 #ifndef PULLDOWN_TEST
 945                                 IP6_EXTHDR_CHECK(m, 0, eoff +
 946                                                  sizeof(struct ip6_frag),
 947                                                  -1);
 948                                 fh = (struct ip6_frag *)(mtod(m, caddr_t)
 949                                                          + eoff);
 950 #else
 951                                 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
 952                                                eoff, sizeof(*fh));
 953                                 if (fh == NULL) {
 954                                         icmp6stat.icp6s_tooshort++;
 955                                         return (-1);
 956                                 }
 957 #endif
 958                                 /*
 959                                  * Data after a fragment header is meaningless
 960                                  * unless it is the first fragment, but
 961                                  * we'll go to the notify label for path MTU
 962                                  * discovery.
 963                                  */
 964                                 if (fh->ip6f_offlg & IP6F_OFF_MASK)
 965                                         goto notify;
 966
 967                                 eoff += sizeof(struct ip6_frag);
 968                                 nxt = fh->ip6f_nxt;
 969                                 break;
 970                         default:
 971                                 /*
 972                                  * This case includes ESP and the No Next
 973                                  * Header.  In such cases going to the notify
 974                                  * label does not have any meaning
 975                                  * (i.e. pr_ctlinput will be NULL), but we go
 976                                  * anyway since we might have to update
 977                                  * path MTU information.
 978                                  */
 979                                 goto notify;
 980                         }
 981                 }
 982           notify:
 983 #ifndef PULLDOWN_TEST
 984                 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
 985 #else
 986                 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
 987                                sizeof(*icmp6) + sizeof(struct ip6_hdr));
 988                 if (icmp6 == NULL) {
 989                         icmp6stat.icp6s_tooshort++;
 990                         return (-1);
 991                 }
 992 #endif
 993
 994                 eip6 = (struct ip6_hdr *)(icmp6 + 1);
 995                 bzero(&icmp6dst, sizeof(icmp6dst));
 996                 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
 997                 icmp6dst.sin6_family = AF_INET6;
 998                 if (finaldst == NULL)
 999                         icmp6dst.sin6_addr = eip6->ip6_dst;
1000                 else
1001                         icmp6dst.sin6_addr = *finaldst;
1002                 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6dst.sin6_addr,
1003                     &icmp6dst.sin6_scope_id))
1004                         goto freeit;
1005                 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst,
1006                                    NULL, NULL)) {
1007                         /* should be impossbile */
1008                         nd6log((LOG_DEBUG,
1009                             "icmp6_notify_error: in6_embedscope failed\n"));
1010                         goto freeit;
1011                 }
1012
1013                 /*
1014                  * retrieve parameters from the inner IPv6 header, and convert
1015                  * them into sockaddr structures.
1016                  */
1017                 bzero(&icmp6src, sizeof(icmp6src));
1018                 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
1019                 icmp6src.sin6_family = AF_INET6;
1020                 icmp6src.sin6_addr = eip6->ip6_src;
1021                 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6src.sin6_addr,
1022                     &icmp6src.sin6_scope_id))
1023                         goto freeit;
1024                 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src,
1025                                    NULL, NULL)) {
1026                         /* should be impossbile */
1027                         nd6log((LOG_DEBUG,
1028                             "icmp6_notify_error: in6_embedscope failed\n"));
1029                         goto freeit;
1030                 }
1031                 icmp6src.sin6_flowinfo =
1032                         (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1033
1034                 if (finaldst == NULL)
1035                         finaldst = &eip6->ip6_dst;
1036                 ip6cp.ip6c_m = m;
1037                 ip6cp.ip6c_icmp6 = icmp6;
1038                 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1039                 ip6cp.ip6c_off = eoff;
1040                 ip6cp.ip6c_finaldst = finaldst;
1041                 ip6cp.ip6c_src = &icmp6src;
1042                 ip6cp.ip6c_nxt = nxt;
1043
1044                 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1045                         notifymtu = ntohl(icmp6->icmp6_mtu);
1046                         ip6cp.ip6c_cmdarg = (void *)&notifymtu;
1047                         icmp6_mtudisc_update(&ip6cp, 1);        /*XXX*/
1048                 }
1049
1050                 so_pr_ctlinput(
1051                         &inet6sw[ip6_protox[nxt]],
1052                         code, (struct sockaddr *)&icmp6dst, &ip6cp);
1053         }
1054         return (0);
1055
1056 freeit:
1057         m_freem(m);
1058         return (-1);
1059 }
1060
1061 void
1062 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
1063 {
1064         struct in6_addr *dst = ip6cp->ip6c_finaldst;
1065         struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1066         struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
1067         u_int mtu = ntohl(icmp6->icmp6_mtu);
1068         struct rtentry *rt = NULL;
1069         struct sockaddr_in6 sin6;
1070
1071         if (!validated)
1072                 return;
1073
1074         bzero(&sin6, sizeof(sin6));
1075         sin6.sin6_family = PF_INET6;
1076         sin6.sin6_len = sizeof(struct sockaddr_in6);
1077         sin6.sin6_addr = *dst;
1078         /* XXX normally, this won't happen */
1079         if (IN6_IS_ADDR_LINKLOCAL(dst)) {
1080                 sin6.sin6_addr.s6_addr16[1] =
1081                     htons(m->m_pkthdr.rcvif->if_index);
1082         }
1083         /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */
1084         rt = rtpurelookup((struct sockaddr *)&sin6);
1085         if (rt != NULL && (rt->rt_flags & RTF_HOST) &&
1086             !(rt->rt_rmx.rmx_locks & RTV_MTU)) {
1087                 if (mtu < IPV6_MMTU) {                          /* XXX */
1088                         rt->rt_rmx.rmx_locks |= RTV_MTU;
1089                 } else if (mtu < rt->rt_ifp->if_mtu &&
1090                            rt->rt_rmx.rmx_mtu > mtu) {
1091                         icmp6stat.icp6s_pmtuchg++;
1092                         rt->rt_rmx.rmx_mtu = mtu;
1093                 }
1094         }
1095         if (rt)
1096                 --rt->rt_refcnt;
1097 }
1098
1099 /*
1100  * Process a Node Information Query packet, based on
1101  * draft-ietf-ipngwg-icmp-name-lookups-07.
1102  *
1103  * Spec incompatibilities:
1104  * - IPv6 Subject address handling
1105  * - IPv4 Subject address handling support missing
1106  * - Proxy reply (answer even if it's not for me)
1107  * - joins NI group address at in6_ifattach() time only, does not cope
1108  *   with hostname changes by sethostname(3)
1109  */
1110 #define hostnamelen     strlen(hostname)
1111 static struct mbuf *
1112 ni6_input(struct mbuf *m, int off)
1113 {
1114         struct icmp6_nodeinfo *ni6, *nni6;
1115         struct mbuf *n = NULL;
1116         u_int16_t qtype;
1117         int subjlen;
1118         int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1119         struct ni_reply_fqdn *fqdn;
1120         int addrs;              /* for NI_QTYPE_NODEADDR */
1121         struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1122         struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */
1123         struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */
1124         struct ip6_hdr *ip6;
1125         int oldfqdn = 0;        /* if 1, return pascal string (03 draft) */
1126         char *subj = NULL;
1127         struct in6_ifaddr *ia6 = NULL;
1128
1129         ip6 = mtod(m, struct ip6_hdr *);
1130 #ifndef PULLDOWN_TEST
1131         ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1132 #else
1133         IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1134         if (ni6 == NULL) {
1135                 /* m is already reclaimed */
1136                 return NULL;
1137         }
1138 #endif
1139
1140         /*
1141          * Validate IPv6 destination address.
1142          *
1143          * The Responder must discard the Query without further processing
1144          * unless it is one of the Responder's unicast or anycast addresses, or
1145          * a link-local scope multicast address which the Responder has joined.
1146          * [icmp-name-lookups-07, Section 4.]
1147          */
1148         bzero(&sin6, sizeof(sin6));
1149         sin6.sin6_family = AF_INET6;
1150         sin6.sin6_len = sizeof(struct sockaddr_in6);
1151         bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr));
1152         /* XXX scopeid */
1153         if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) {
1154                 /* unicast/anycast, fine */
1155                 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
1156                     (icmp6_nodeinfo & 4) == 0) {
1157                         nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
1158                                 "a temporary address in %s:%d",
1159                                __FILE__, __LINE__));
1160                         goto bad;
1161                 }
1162         } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr))
1163                 ; /* link-local multicast, fine */
1164         else
1165                 goto bad;
1166
1167         /* validate query Subject field. */
1168         qtype = ntohs(ni6->ni_qtype);
1169         subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1170         switch (qtype) {
1171         case NI_QTYPE_NOOP:
1172         case NI_QTYPE_SUPTYPES:
1173                 /* 07 draft */
1174                 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1175                         break;
1176                 /* FALLTHROUGH */
1177         case NI_QTYPE_FQDN:
1178         case NI_QTYPE_NODEADDR:
1179                 switch (ni6->ni_code) {
1180                 case ICMP6_NI_SUBJ_IPV6:
1181 #if ICMP6_NI_SUBJ_IPV6 != 0
1182                 case 0:
1183 #endif
1184                         /*
1185                          * backward compatibility - try to accept 03 draft
1186                          * format, where no Subject is present.
1187                          */
1188                         if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1189                             subjlen == 0) {
1190                                 oldfqdn++;
1191                                 break;
1192                         }
1193 #if ICMP6_NI_SUBJ_IPV6 != 0
1194                         if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1195                                 goto bad;
1196 #endif
1197
1198                         if (subjlen != sizeof(sin6.sin6_addr))
1199                                 goto bad;
1200
1201                         /*
1202                          * Validate Subject address.
1203                          *
1204                          * Not sure what exactly "address belongs to the node"
1205                          * means in the spec, is it just unicast, or what?
1206                          *
1207                          * At this moment we consider Subject address as
1208                          * "belong to the node" if the Subject address equals
1209                          * to the IPv6 destination address; validation for
1210                          * IPv6 destination address should have done enough
1211                          * check for us.
1212                          *
1213                          * We do not do proxy at this moment.
1214                          */
1215                         /* m_pulldown instead of copy? */
1216                         m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1217                             subjlen, (caddr_t)&sin6.sin6_addr);
1218                         if (in6_addr2zoneid(m->m_pkthdr.rcvif,
1219                             &sin6.sin6_addr, &sin6.sin6_scope_id))
1220                                 goto bad;
1221                         in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL);
1222                         bzero(&sin6_d, sizeof(sin6_d));
1223                         sin6_d.sin6_family = AF_INET6; /* not used, actually */
1224                         sin6_d.sin6_len = sizeof(sin6_d); /* ditto */
1225                         sin6_d.sin6_addr = ip6->ip6_dst;
1226                         if (in6_addr2zoneid(m->m_pkthdr.rcvif,
1227                             &ip6->ip6_dst, &sin6_d.sin6_scope_id))
1228                                 goto bad;
1229                         in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL);
1230                         subj = (char *)&sin6;
1231                         if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d))
1232                                 break;
1233
1234                         /*
1235                          * XXX if we are to allow other cases, we should really
1236                          * be careful about scope here.
1237                          * basically, we should disallow queries toward IPv6
1238                          * destination X with subject Y, if scope(X) > scope(Y).
1239                          * if we allow scope(X) > scope(Y), it will result in
1240                          * information leakage across scope boundary.
1241                          */
1242                         goto bad;
1243
1244                 case ICMP6_NI_SUBJ_FQDN:
1245                         /*
1246                          * Validate Subject name with gethostname(3).
1247                          *
1248                          * The behavior may need some debate, since:
1249                          * - we are not sure if the node has FQDN as
1250                          *   hostname (returned by gethostname(3)).
1251                          * - the code does wildcard match for truncated names.
1252                          *   however, we are not sure if we want to perform
1253                          *   wildcard match, if gethostname(3) side has
1254                          *   truncated hostname.
1255                          */
1256                         n = ni6_nametodns(hostname, hostnamelen, 0);
1257                         if (!n || n->m_next || n->m_len == 0)
1258                                 goto bad;
1259                         IP6_EXTHDR_GET(subj, char *, m,
1260                             off + sizeof(struct icmp6_nodeinfo), subjlen);
1261                         if (subj == NULL)
1262                                 goto bad;
1263                         if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1264                                         n->m_len)) {
1265                                 goto bad;
1266                         }
1267                         m_freem(n);
1268                         n = NULL;
1269                         break;
1270
1271                 case ICMP6_NI_SUBJ_IPV4:        /* XXX: to be implemented? */
1272                 default:
1273                         goto bad;
1274                 }
1275                 break;
1276         }
1277
1278         /* refuse based on configuration.  XXX ICMP6_NI_REFUSED? */
1279         switch (qtype) {
1280         case NI_QTYPE_FQDN:
1281                 if ((icmp6_nodeinfo & 1) == 0)
1282                         goto bad;
1283                 break;
1284         case NI_QTYPE_NODEADDR:
1285                 if ((icmp6_nodeinfo & 2) == 0)
1286                         goto bad;
1287                 break;
1288         }
1289
1290         /* guess reply length */
1291         switch (qtype) {
1292         case NI_QTYPE_NOOP:
1293                 break;          /* no reply data */
1294         case NI_QTYPE_SUPTYPES:
1295                 replylen += sizeof(u_int32_t);
1296                 break;
1297         case NI_QTYPE_FQDN:
1298                 /* XXX will append an mbuf */
1299                 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1300                 break;
1301         case NI_QTYPE_NODEADDR:
1302                 addrs = ni6_addrs(ni6, m, &ifp, subj);
1303                 if ((replylen += addrs * (sizeof(struct in6_addr) +
1304                                           sizeof(u_int32_t))) > MCLBYTES)
1305                         replylen = MCLBYTES; /* XXX: will truncate pkt later */
1306                 break;
1307         default:
1308                 /*
1309                  * XXX: We must return a reply with the ICMP6 code
1310                  * `unknown Qtype' in this case. However we regard the case
1311                  * as an FQDN query for backward compatibility.
1312                  * Older versions set a random value to this field,
1313                  * so it rarely varies in the defined qtypes.
1314                  * But the mechanism is not reliable...
1315                  * maybe we should obsolete older versions.
1316                  */
1317                 qtype = NI_QTYPE_FQDN;
1318                 /* XXX will append an mbuf */
1319                 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1320                 oldfqdn++;
1321                 break;
1322         }
1323
1324         /* allocate an mbuf to reply. */
1325         if (replylen > MCLBYTES) {
1326                 /*
1327                  * XXX: should we try to allocate more? But MCLBYTES
1328                  * is probably much larger than IPV6_MMTU...
1329                  */
1330                 goto bad;
1331         }
1332         n = m_getb(replylen, M_NOWAIT, m->m_type, M_PKTHDR);
1333         if (n == NULL) {
1334                 m_freem(m);
1335                 return (NULL);
1336         }
1337         M_MOVE_PKTHDR(n, m); /* just for recvif */
1338         n->m_pkthdr.len = n->m_len = replylen;
1339
1340         /* copy mbuf header and IPv6 + Node Information base headers */
1341         bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1342         nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1343         bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1344
1345         /* qtype dependent procedure */
1346         switch (qtype) {
1347         case NI_QTYPE_NOOP:
1348                 nni6->ni_code = ICMP6_NI_SUCCESS;
1349                 nni6->ni_flags = 0;
1350                 break;
1351         case NI_QTYPE_SUPTYPES:
1352         {
1353                 u_int32_t v;
1354                 nni6->ni_code = ICMP6_NI_SUCCESS;
1355                 nni6->ni_flags = htons(0x0000); /* raw bitmap */
1356                 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1357                 v = (u_int32_t)htonl(0x0000000f);
1358                 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
1359                 break;
1360         }
1361         case NI_QTYPE_FQDN:
1362                 nni6->ni_code = ICMP6_NI_SUCCESS;
1363                 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1364                                                 sizeof(struct ip6_hdr) +
1365                                                 sizeof(struct icmp6_nodeinfo));
1366                 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1367                 fqdn->ni_fqdn_ttl = 0;  /* ditto. */
1368                 /*
1369                  * XXX do we really have FQDN in variable "hostname"?
1370                  */
1371                 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
1372                 if (n->m_next == NULL)
1373                         goto bad;
1374                 /* XXX we assume that n->m_next is not a chain */
1375                 if (n->m_next->m_next != NULL)
1376                         goto bad;
1377                 n->m_pkthdr.len += n->m_next->m_len;
1378                 break;
1379         case NI_QTYPE_NODEADDR:
1380         {
1381                 int lenlim, copied;
1382
1383                 nni6->ni_code = ICMP6_NI_SUCCESS;
1384                 n->m_pkthdr.len = n->m_len =
1385                     sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1386                 lenlim = M_TRAILINGSPACE(n);
1387                 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1388                 /* XXX: reset mbuf length */
1389                 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1390                         sizeof(struct icmp6_nodeinfo) + copied;
1391                 break;
1392         }
1393         default:
1394                 break;          /* XXX impossible! */
1395         }
1396
1397         nni6->ni_type = ICMP6_NI_REPLY;
1398         m_freem(m);
1399         return (n);
1400
1401 bad:
1402         m_freem(m);
1403         if (n)
1404                 m_freem(n);
1405         return (NULL);
1406 }
1407 #undef hostnamelen
1408
1409 /*
1410  * make a mbuf with DNS-encoded string.  no compression support.
1411  *
1412  * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1413  * treated as truncated name (two \0 at the end).  this is a wild guess.
1414  */
1415 static struct mbuf *
1416 ni6_nametodns(const char *name, int namelen,
1417               int old) /* return pascal string if non-zero */
1418 {
1419         struct mbuf *m;
1420         char *cp, *ep;
1421         const char *p, *q;
1422         int i, len, nterm;
1423
1424         if (old)
1425                 len = namelen + 1;
1426         else
1427                 len = MCLBYTES;
1428
1429         /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
1430         m = m_getb(len, M_NOWAIT, MT_DATA, 0);
1431         if (!m)
1432                 goto fail;
1433
1434         if (old) {
1435                 m->m_len = len;
1436                 *mtod(m, char *) = namelen;
1437                 bcopy(name, mtod(m, char *) + 1, namelen);
1438                 return m;
1439         } else {
1440                 m->m_len = 0;
1441                 cp = mtod(m, char *);
1442                 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1443
1444                 /* if not certain about my name, return empty buffer */
1445                 if (namelen == 0)
1446                         return m;
1447
1448                 /*
1449                  * guess if it looks like shortened hostname, or FQDN.
1450                  * shortened hostname needs two trailing "\0".
1451                  */
1452                 i = 0;
1453                 for (p = name; p < name + namelen; p++) {
1454                         if (*p && *p == '.')
1455                                 i++;
1456                 }
1457                 if (i < 2)
1458                         nterm = 2;
1459                 else
1460                         nterm = 1;
1461
1462                 p = name;
1463                 while (cp < ep && p < name + namelen) {
1464                         i = 0;
1465                         for (q = p; q < name + namelen && *q && *q != '.'; q++)
1466                                 i++;
1467                         /* result does not fit into mbuf */
1468                         if (cp + i + 1 >= ep)
1469                                 goto fail;
1470                         /*
1471                          * DNS label length restriction, RFC1035 page 8.
1472                          * "i == 0" case is included here to avoid returning
1473                          * 0-length label on "foo..bar".
1474                          */
1475                         if (i <= 0 || i >= 64)
1476                                 goto fail;
1477                         *cp++ = i;
1478                         bcopy(p, cp, i);
1479                         cp += i;
1480                         p = q;
1481                         if (p < name + namelen && *p == '.')
1482                                 p++;
1483                 }
1484                 /* termination */
1485                 if (cp + nterm >= ep)
1486                         goto fail;
1487                 while (nterm-- > 0)
1488                         *cp++ = '\0';
1489                 m->m_len = cp - mtod(m, char *);
1490                 return m;
1491         }
1492
1493         panic("should not reach here");
1494         /* NOTREACHED */
1495
1496 fail:
1497         if (m)
1498                 m_freem(m);
1499         return NULL;
1500 }
1501
1502 /*
1503  * check if two DNS-encoded string matches.  takes care of truncated
1504  * form (with \0\0 at the end).  no compression support.
1505  * XXX upper/lowercase match (see RFC2065)
1506  */
1507 static int
1508 ni6_dnsmatch(const char *a, int alen, const char *b, int blen)
1509 {
1510         const char *a0, *b0;
1511         int l;
1512
1513         /* simplest case - need validation? */
1514         if (alen == blen && bcmp(a, b, alen) == 0)
1515                 return 1;
1516
1517         a0 = a;
1518         b0 = b;
1519
1520         /* termination is mandatory */
1521         if (alen < 2 || blen < 2)
1522                 return 0;
1523         if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1524                 return 0;
1525         alen--;
1526         blen--;
1527
1528         while (a - a0 < alen && b - b0 < blen) {
1529                 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1530                         return 0;
1531
1532                 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1533                         return 0;
1534                 /* we don't support compression yet */
1535                 if (a[0] >= 64 || b[0] >= 64)
1536                         return 0;
1537
1538                 /* truncated case */
1539                 if (a[0] == 0 && a - a0 == alen - 1)
1540                         return 1;
1541                 if (b[0] == 0 && b - b0 == blen - 1)
1542                         return 1;
1543                 if (a[0] == 0 || b[0] == 0)
1544                         return 0;
1545
1546                 if (a[0] != b[0])
1547                         return 0;
1548                 l = a[0];
1549                 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1550                         return 0;
1551                 if (bcmp(a + 1, b + 1, l) != 0)
1552                         return 0;
1553
1554                 a += 1 + l;
1555                 b += 1 + l;
1556         }
1557
1558         if (a - a0 == alen && b - b0 == blen)
1559                 return 1;
1560         else
1561                 return 0;
1562 }
1563
1564 /*
1565  * calculate the number of addresses to be returned in the node info reply.
1566  */
1567 static int
1568 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp,
1569           char *subj)
1570 {
1571         const struct ifnet_array *arr;
1572         struct in6_ifaddr *ifa6;
1573         struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */
1574         int addrs = 0, addrsofif, iffound = 0;
1575         int niflags = ni6->ni_flags;
1576         int i;
1577
1578         if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1579                 switch (ni6->ni_code) {
1580                 case ICMP6_NI_SUBJ_IPV6:
1581                         if (subj == NULL) /* must be impossible... */
1582                                 return (0);
1583                         subj_ip6 = (struct sockaddr_in6 *)subj;
1584                         break;
1585                 default:
1586                         /*
1587                          * XXX: we only support IPv6 subject address for
1588                          * this Qtype.
1589                          */
1590                         return (0);
1591                 }
1592         }
1593
1594         arr = ifnet_array_get();
1595         for (i = 0; i < arr->ifnet_count; ++i) {
1596                 struct ifnet *ifp = arr->ifnet_arr[i];
1597                 struct ifaddr_container *ifac;
1598
1599                 addrsofif = 0;
1600                 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link)
1601                 {
1602                         struct ifaddr *ifa = ifac->ifa;
1603
1604                         if (ifa->ifa_addr->sa_family != AF_INET6)
1605                                 continue;
1606                         ifa6 = (struct in6_ifaddr *)ifa;
1607
1608                         if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1609                             IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr,
1610                                                &ifa6->ia_addr.sin6_addr))
1611                                 iffound = 1;
1612
1613                         /*
1614                          * IPv4-mapped addresses can only be returned by a
1615                          * Node Information proxy, since they represent
1616                          * addresses of IPv4-only nodes, which perforce do
1617                          * not implement this protocol.
1618                          * [icmp-name-lookups-07, Section 5.4]
1619                          * So we don't support NI_NODEADDR_FLAG_COMPAT in
1620                          * this function at this moment.
1621                          */
1622
1623                         /* What do we have to do about ::1? */
1624                         switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1625                         case IPV6_ADDR_SCOPE_LINKLOCAL:
1626                                 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1627                                         continue;
1628                                 break;
1629                         case IPV6_ADDR_SCOPE_SITELOCAL:
1630                                 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1631                                         continue;
1632                                 break;
1633                         case IPV6_ADDR_SCOPE_GLOBAL:
1634                                 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1635                                         continue;
1636                                 break;
1637                         default:
1638                                 continue;
1639                         }
1640
1641                         /*
1642                          * check if anycast is okay.
1643                          * XXX: just experimental.  not in the spec.
1644                          */
1645                         if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) &&
1646                             !(niflags & NI_NODEADDR_FLAG_ANYCAST))
1647                                 continue; /* we need only unicast addresses */
1648                         if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) &&
1649                             (icmp6_nodeinfo & 4) == 0) {
1650                                 continue;
1651                         }
1652                         addrsofif++; /* count the address */
1653                 }
1654                 if (iffound) {
1655                         *ifpp = ifp;
1656                         return (addrsofif);
1657                 }
1658
1659                 addrs += addrsofif;
1660         }
1661
1662         return (addrs);
1663 }
1664
1665 static int
1666 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6,
1667                 struct ifnet *ifp0, int resid)
1668 {
1669         const struct ifnet_array *arr;
1670         struct in6_ifaddr *ifa6;
1671         int copied = 0, allow_deprecated = 0;
1672         u_char *cp = (u_char *)(nni6 + 1);
1673         int niflags = ni6->ni_flags;
1674         u_int32_t ltime;
1675         int idx, idx_dep = -1;
1676
1677         if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1678                 return (0);     /* needless to copy */
1679
1680         arr = ifnet_array_get();
1681         if (ifp0 == NULL) {
1682                 idx = 0;
1683         } else {
1684                 for (idx = 0; idx < arr->ifnet_count; ++idx) {
1685                         if (arr->ifnet_arr[idx] == ifp0)
1686                                 break;
1687                 }
1688         }
1689
1690 again:
1691
1692         for (; idx < arr->ifnet_count; ++idx) {
1693                 struct ifnet *ifp = arr->ifnet_arr[idx];
1694                 struct ifaddr_container *ifac;
1695
1696                 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
1697                         struct ifaddr *ifa = ifac->ifa;
1698
1699                         if (ifa->ifa_addr->sa_family != AF_INET6)
1700                                 continue;
1701                         ifa6 = (struct in6_ifaddr *)ifa;
1702
1703                         if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) &&
1704                             allow_deprecated == 0) {
1705                                 /*
1706                                  * prefererred address should be put before
1707                                  * deprecated addresses.
1708                                  */
1709
1710                                 /* record the interface for later search */
1711                                 if (idx_dep < 0)
1712                                         idx_dep = idx;
1713
1714                                 continue;
1715                         }
1716                         else if (!(ifa6->ia6_flags & IN6_IFF_DEPRECATED) &&
1717                                  allow_deprecated != 0)
1718                                 continue; /* we now collect deprecated addrs */
1719
1720                         /* What do we have to do about ::1? */
1721                         switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1722                         case IPV6_ADDR_SCOPE_LINKLOCAL:
1723                                 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1724                                         continue;
1725                                 break;
1726                         case IPV6_ADDR_SCOPE_SITELOCAL:
1727                                 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1728                                         continue;
1729                                 break;
1730                         case IPV6_ADDR_SCOPE_GLOBAL:
1731                                 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1732                                         continue;
1733                                 break;
1734                         default:
1735                                 continue;
1736                         }
1737
1738                         /*
1739                          * check if anycast is okay.
1740                          * XXX: just experimental. not in the spec.
1741                          */
1742                         if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) &&
1743                             !(niflags & NI_NODEADDR_FLAG_ANYCAST))
1744                                 continue;
1745                         if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) &&
1746                             (icmp6_nodeinfo & 4) == 0) {
1747                                 continue;
1748                         }
1749
1750                         /* now we can copy the address */
1751                         if (resid < sizeof(struct in6_addr) +
1752                             sizeof(u_int32_t)) {
1753                                 /*
1754                                  * We give up much more copy.
1755                                  * Set the truncate flag and return.
1756                                  */
1757                                 nni6->ni_flags |=
1758                                         NI_NODEADDR_FLAG_TRUNCATE;
1759                                 return (copied);
1760                         }
1761
1762                         /*
1763                          * Set the TTL of the address.
1764                          * The TTL value should be one of the following
1765                          * according to the specification:
1766                          *
1767                          * 1. The remaining lifetime of a DHCP lease on the
1768                          *    address, or
1769                          * 2. The remaining Valid Lifetime of a prefix from
1770                          *    which the address was derived through Stateless
1771                          *    Autoconfiguration.
1772                          *
1773                          * Note that we currently do not support stateful
1774                          * address configuration by DHCPv6, so the former
1775                          * case can't happen.
1776                          */
1777                         if (ifa6->ia6_lifetime.ia6t_expire == 0)
1778                                 ltime = ND6_INFINITE_LIFETIME;
1779                         else {
1780                                 if (ifa6->ia6_lifetime.ia6t_expire >
1781                                     time_uptime)
1782                                         ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_uptime);
1783                                 else
1784                                         ltime = 0;
1785                         }
1786
1787                         bcopy(&ltime, cp, sizeof(u_int32_t));
1788                         cp += sizeof(u_int32_t);
1789
1790                         /* copy the address itself */
1791                         bcopy(&ifa6->ia_addr.sin6_addr, cp,
1792                               sizeof(struct in6_addr));
1793                         in6_clearscope((struct in6_addr *)cp); /* XXX */
1794                         cp += sizeof(struct in6_addr);
1795
1796                         resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1797                         copied += (sizeof(struct in6_addr) +
1798                                    sizeof(u_int32_t));
1799                 }
1800                 if (ifp0)       /* we need search only on the specified IF */
1801                         break;
1802         }
1803
1804         if (allow_deprecated == 0 && idx_dep >= 0) {
1805                 idx = idx_dep;
1806                 allow_deprecated = 1;
1807
1808                 goto again;
1809         }
1810
1811         return (copied);
1812 }
1813
1814 /*
1815  * XXX almost dup'ed code with rip6_input.
1816  */
1817 static int
1818 icmp6_rip6_input(struct mbuf **mp, int  off)
1819 {
1820         struct mbuf *m = *mp;
1821         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1822         struct in6pcb *in6p;
1823         struct in6pcb *last = NULL;
1824         struct sockaddr_in6 fromsa;
1825         struct icmp6_hdr *icmp6;
1826         struct mbuf *opts = NULL;
1827
1828 #ifndef PULLDOWN_TEST
1829         /* this is assumed to be safe. */
1830         icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1831 #else
1832         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1833         if (icmp6 == NULL) {
1834                 /* m is already reclaimed */
1835                 return IPPROTO_DONE;
1836         }
1837 #endif
1838
1839         bzero(&fromsa, sizeof(fromsa));
1840         fromsa.sin6_len = sizeof(struct sockaddr_in6);
1841         fromsa.sin6_family = AF_INET6;
1842         /* KAME hack: recover scopeid */
1843         in6_recoverscope(&fromsa, &ip6->ip6_src, m->m_pkthdr.rcvif);
1844
1845         LIST_FOREACH(in6p, &ripcbinfo.pcblisthead, inp_list)
1846         {
1847                 if (in6p->inp_flags & INP_PLACEMARKER)
1848                         continue;
1849                 if (!INP_ISIPV6(in6p))
1850                         continue;
1851                 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
1852                         continue;
1853                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
1854                    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
1855                         continue;
1856                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
1857                    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
1858                         continue;
1859                 if (in6p->in6p_icmp6filt
1860                     && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
1861                                  in6p->in6p_icmp6filt))
1862                         continue;
1863                 if (last) {
1864                         struct socket *so;
1865                         struct mbuf *n;
1866
1867                         if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
1868                                 if (last->in6p_flags & IN6P_CONTROLOPTS)
1869                                         ip6_savecontrol(last, &opts, ip6, n);
1870                                 /* strip intermediate headers */
1871                                 m_adj(n, off);
1872                                 so = last->in6p_socket;
1873                                 lwkt_gettoken(&so->so_rcv.ssb_token);
1874                                 if (ssb_appendaddr(&so->so_rcv,
1875                                     (struct sockaddr *)&fromsa, n, opts) == 0) {
1876                                         /* should notify about lost packet */
1877                                         m_freem(n);
1878                                         if (opts)
1879                                                 m_freem(opts);
1880                                 } else {
1881                                         sorwakeup(so);
1882                                 }
1883                                 lwkt_reltoken(&so->so_rcv.ssb_token);
1884                                 opts = NULL;
1885                         }
1886                 }
1887                 last = in6p;
1888         }
1889         if (last) {
1890                 struct socket *so;
1891
1892                 if (last->in6p_flags & IN6P_CONTROLOPTS)
1893                         ip6_savecontrol(last, &opts, ip6, m);
1894                 /* strip intermediate headers */
1895                 m_adj(m, off);
1896                 so = last->in6p_socket;
1897                 lwkt_gettoken(&so->so_rcv.ssb_token);
1898                 if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *)&fromsa,
1899                     m, opts) == 0) {
1900                         m_freem(m);
1901                         if (opts)
1902                                 m_freem(opts);
1903                 } else {
1904                         sorwakeup(so);
1905                 }
1906                 lwkt_reltoken(&so->so_rcv.ssb_token);
1907         } else {
1908                 m_freem(m);
1909                 ip6stat.ip6s_delivered--;
1910         }
1911         return IPPROTO_DONE;
1912 }
1913
1914 /*
1915  * Reflect the ip6 packet back to the source.
1916  * OFF points to the icmp6 header, counted from the top of the mbuf.
1917  */
1918 void
1919 icmp6_reflect(struct mbuf *m, size_t off)
1920 {
1921         struct ip6_hdr *ip6;
1922         struct icmp6_hdr *icmp6;
1923         struct in6_ifaddr *ia;
1924         struct in6_addr t, *src = NULL;
1925         int plen;
1926         int type, code;
1927         struct ifnet *outif = NULL;
1928         struct sockaddr_in6 sa6_src, sa6_dst;
1929 #ifdef COMPAT_RFC1885
1930         int mtu = IPV6_MMTU;
1931         struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
1932 #endif
1933
1934         /* too short to reflect */
1935         if (off < sizeof(struct ip6_hdr)) {
1936                 nd6log((LOG_DEBUG,
1937                     "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
1938                     (u_long)off, (u_long)sizeof(struct ip6_hdr),
1939                     __FILE__, __LINE__));
1940                 goto bad;
1941         }
1942
1943         /*
1944          * If there are extra headers between IPv6 and ICMPv6, strip
1945          * off that header first.
1946          */
1947 #ifdef DIAGNOSTIC
1948         if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
1949                 panic("assumption failed in icmp6_reflect");
1950 #endif
1951         if (off > sizeof(struct ip6_hdr)) {
1952                 size_t l;
1953                 struct ip6_hdr nip6;
1954
1955                 l = off - sizeof(struct ip6_hdr);
1956                 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
1957                 m_adj(m, l);
1958                 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
1959                 if (m->m_len < l) {
1960                         if ((m = m_pullup(m, l)) == NULL)
1961                                 return;
1962                 }
1963                 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
1964         } else /* off == sizeof(struct ip6_hdr) */ {
1965                 size_t l;
1966                 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
1967                 if (m->m_len < l) {
1968                         if ((m = m_pullup(m, l)) == NULL)
1969                                 return;
1970                 }
1971         }
1972         plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
1973         ip6 = mtod(m, struct ip6_hdr *);
1974         ip6->ip6_nxt = IPPROTO_ICMPV6;
1975         icmp6 = (struct icmp6_hdr *)(ip6 + 1);
1976         type = icmp6->icmp6_type; /* keep type for statistics */
1977         code = icmp6->icmp6_code; /* ditto. */
1978
1979         t = ip6->ip6_dst;
1980         /*
1981          * ip6_input() drops a packet if its src is multicast.
1982          * So, the src is never multicast.
1983          */
1984         ip6->ip6_dst = ip6->ip6_src;
1985
1986         /*
1987          * XXX: make sure to embed scope zone information, using
1988          * already embedded IDs or the received interface (if any).
1989          * Note that rcvif may be NULL.
1990          * TODO: scoped routing case (XXX).
1991          */
1992         bzero(&sa6_src, sizeof(sa6_src));
1993         sa6_src.sin6_family = AF_INET6;
1994         sa6_src.sin6_len = sizeof(sa6_src);
1995         sa6_src.sin6_addr = ip6->ip6_dst;
1996         in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif);
1997         in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL);
1998         bzero(&sa6_dst, sizeof(sa6_dst));
1999         sa6_dst.sin6_family = AF_INET6;
2000         sa6_dst.sin6_len = sizeof(sa6_dst);
2001         sa6_dst.sin6_addr = t;
2002         in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif);
2003         in6_embedscope(&t, &sa6_dst, NULL, NULL);
2004
2005 #ifdef COMPAT_RFC1885
2006         /*
2007          * xxx guess MTU
2008          * RFC 1885 requires that echo reply should be truncated if it
2009          * does not fit in with (return) path MTU, but the description was
2010          * removed in the new spec.
2011          */
2012         if (icmp6_reflect_rt.ro_rt == 0 ||
2013             ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) {
2014                 if (icmp6_reflect_rt.ro_rt) {
2015                         RTFREE(icmp6_reflect_rt.ro_rt);
2016                         icmp6_reflect_rt.ro_rt = 0;
2017                 }
2018                 bzero(sin6, sizeof(*sin6));
2019                 sin6->sin6_family = PF_INET6;
2020                 sin6->sin6_len = sizeof(struct sockaddr_in6);
2021                 sin6->sin6_addr = ip6->ip6_dst;
2022
2023                 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt,
2024                             RTF_PRCLONING);
2025         }
2026
2027         if (icmp6_reflect_rt.ro_rt == 0)
2028                 goto bad;
2029
2030         if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST)
2031             && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu)
2032                 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu;
2033
2034         if (mtu < m->m_pkthdr.len) {
2035                 plen -= (m->m_pkthdr.len - mtu);
2036                 m_adj(m, mtu - m->m_pkthdr.len);
2037         }
2038 #endif
2039         /*
2040          * If the incoming packet was addressed directly to us(i.e. unicast),
2041          * use dst as the src for the reply.
2042          * The IN6_IFF_NOTREADY case would be VERY rare, but is possible
2043          * (for example) when we encounter an error while forwarding procedure
2044          * destined to a duplicated address of ours.
2045          */
2046         for (ia = in6_ifaddr; ia; ia = ia->ia_next)
2047                 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) &&
2048                     (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) {
2049                         src = &t;
2050                         break;
2051                 }
2052         if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) {
2053                 /*
2054                  * This is the case if the dst is our link-local address
2055                  * and the sender is also ourselves.
2056                  */
2057                 src = &t;
2058         }
2059
2060         if (src == NULL) {
2061                 int e;
2062                 struct route_in6 ro;
2063
2064                 /*
2065                  * This case matches to multicasts, our anycast, or unicasts
2066                  * that we do not own.  Select a source address based on the
2067                  * source address of the erroneous packet.
2068                  */
2069                 bzero(&ro, sizeof(ro));
2070                 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e, NULL);
2071                 if (ro.ro_rt)
2072                         RTFREE(ro.ro_rt); /* XXX: we could use this */
2073                 if (src == NULL) {
2074                         nd6log((LOG_DEBUG,
2075                             "icmp6_reflect: source can't be determined: "
2076                             "dst=%s, error=%d\n",
2077                             ip6_sprintf(&sa6_src.sin6_addr), e));
2078                         goto bad;
2079                 }
2080         }
2081
2082         ip6->ip6_src = *src;
2083
2084         ip6->ip6_flow = 0;
2085         ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2086         ip6->ip6_vfc |= IPV6_VERSION;
2087         ip6->ip6_nxt = IPPROTO_ICMPV6;
2088         if (m->m_pkthdr.rcvif) {
2089                 /* XXX: This may not be the outgoing interface */
2090                 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
2091                 if (ip6->ip6_hlim < ip6_minhlim)
2092                         ip6->ip6_hlim = ip6_minhlim;
2093         } else {
2094                 ip6->ip6_hlim = ip6_defhlim;
2095         }
2096
2097         icmp6->icmp6_cksum = 0;
2098         icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2099                                         sizeof(struct ip6_hdr), plen);
2100
2101         /*
2102          * XXX option handling
2103          */
2104
2105         m->m_flags &= ~(M_BCAST|M_MCAST);
2106
2107 #ifdef COMPAT_RFC1885
2108         ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL);
2109 #else
2110         ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2111 #endif
2112         if (outif)
2113                 icmp6_ifoutstat_inc(outif, type, code);
2114
2115         return;
2116
2117 bad:
2118         m_freem(m);
2119         return;
2120 }
2121
2122 void
2123 icmp6_fasttimo(void)
2124 {
2125
2126         mld6_fasttimeo();
2127 }
2128
2129 static const char *
2130 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6,
2131                     struct in6_addr *tgt6)
2132 {
2133         static char buf[1024];
2134         ksnprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
2135                 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
2136         return buf;
2137 }
2138
2139 void
2140 icmp6_redirect_input(struct mbuf *m, int off)
2141 {
2142         struct ifnet *ifp = m->m_pkthdr.rcvif;
2143         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2144         struct nd_redirect *nd_rd;
2145         int icmp6len = ntohs(ip6->ip6_plen);
2146         char *lladdr = NULL;
2147         int lladdrlen = 0;
2148 #if 0
2149         u_char *redirhdr = NULL;
2150         int redirhdrlen = 0;
2151 #endif
2152         struct rtentry *rt = NULL;
2153         int is_router;
2154         int is_onlink;
2155         struct in6_addr src6 = ip6->ip6_src;
2156         struct in6_addr redtgt6;
2157         struct in6_addr reddst6;
2158         union nd_opts ndopts;
2159
2160         if (!m || !ifp)
2161                 return;
2162
2163         /* XXX if we are router, we don't update route by icmp6 redirect */
2164         if (ip6_forwarding)
2165                 goto freeit;
2166         if (!icmp6_rediraccept)
2167                 goto freeit;
2168
2169 #ifndef PULLDOWN_TEST
2170         IP6_EXTHDR_CHECK(m, off, icmp6len,);
2171         nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2172 #else
2173         IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2174         if (nd_rd == NULL) {
2175                 icmp6stat.icp6s_tooshort++;
2176                 return;
2177         }
2178 #endif
2179         redtgt6 = nd_rd->nd_rd_target;
2180         reddst6 = nd_rd->nd_rd_dst;
2181
2182         if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2183                 redtgt6.s6_addr16[1] = htons(ifp->if_index);
2184         if (IN6_IS_ADDR_LINKLOCAL(&reddst6))
2185                 reddst6.s6_addr16[1] = htons(ifp->if_index);
2186
2187         /* validation */
2188         if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2189                 nd6log((LOG_ERR,
2190                         "ICMP6 redirect sent from %s rejected; "
2191                         "must be from linklocal\n", ip6_sprintf(&src6)));
2192                 goto bad;
2193         }
2194         if (ip6->ip6_hlim != 255) {
2195                 nd6log((LOG_ERR,
2196                         "ICMP6 redirect sent from %s rejected; "
2197                         "hlim=%d (must be 255)\n",
2198                         ip6_sprintf(&src6), ip6->ip6_hlim));
2199                 goto bad;
2200         }
2201     {
2202         /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2203         struct sockaddr_in6 sin6;
2204         struct in6_addr *gw6;
2205
2206         bzero(&sin6, sizeof(sin6));
2207         sin6.sin6_family = AF_INET6;
2208         sin6.sin6_len = sizeof(struct sockaddr_in6);
2209         bcopy(&reddst6, &sin6.sin6_addr, sizeof reddst6);
2210         rt = rtpurelookup((struct sockaddr *)&sin6);
2211         if (rt != NULL) {
2212                 if (rt->rt_gateway == NULL ||
2213                     rt->rt_gateway->sa_family != AF_INET6) {
2214                         nd6log((LOG_ERR,
2215                             "ICMP6 redirect rejected; no route "
2216                             "with inet6 gateway found for redirect dst: %s\n",
2217                             icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2218                         --rt->rt_refcnt;
2219                         goto bad;
2220                 }
2221
2222                 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2223                 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2224                         nd6log((LOG_ERR,
2225                                 "ICMP6 redirect rejected; "
2226                                 "not equal to gw-for-src=%s (must be same): "
2227                                 "%s\n",
2228                                 ip6_sprintf(gw6),
2229                                 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2230                         --rt->rt_refcnt;
2231                         goto bad;
2232                 }
2233         } else {
2234                 nd6log((LOG_ERR,
2235                         "ICMP6 redirect rejected; "
2236                         "no route found for redirect dst: %s\n",
2237                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2238                 goto bad;
2239         }
2240         --rt->rt_refcnt;
2241         rt = NULL;
2242     }
2243         if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2244                 nd6log((LOG_ERR,
2245                         "ICMP6 redirect rejected; "
2246                         "redirect dst must be unicast: %s\n",
2247                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2248                 goto bad;
2249         }
2250
2251         is_router = is_onlink = 0;
2252         if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2253                 is_router = 1;  /* router case */
2254         if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2255                 is_onlink = 1;  /* on-link destination case */
2256         if (!is_router && !is_onlink) {
2257                 nd6log((LOG_ERR,
2258                         "ICMP6 redirect rejected; "
2259                         "neither router case nor onlink case: %s\n",
2260                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2261                 goto bad;
2262         }
2263         /* validation passed */
2264
2265         icmp6len -= sizeof(*nd_rd);
2266         nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2267         if (nd6_options(&ndopts) < 0) {
2268                 nd6log((LOG_INFO, "icmp6_redirect_input: "
2269                         "invalid ND option, rejected: %s\n",
2270                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2271                 /* nd6_options have incremented stats */
2272                 goto freeit;
2273         }
2274
2275         if (ndopts.nd_opts_tgt_lladdr) {
2276                 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2277                 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2278         }
2279
2280 #if 0
2281         if (ndopts.nd_opts_rh) {
2282                 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
2283                 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
2284         }
2285 #endif
2286
2287         if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2288                 nd6log((LOG_INFO,
2289                         "icmp6_redirect_input: lladdrlen mismatch for %s "
2290                         "(if %d, icmp6 packet %d): %s\n",
2291                         ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
2292                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2293                 goto bad;
2294         }
2295
2296         /* RFC 2461 8.3 */
2297         nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2298                          is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2299
2300         if (!is_onlink) {       /* better router case.  perform rtredirect. */
2301                 /* perform rtredirect */
2302                 struct sockaddr_in6 sdst;
2303                 struct sockaddr_in6 sgw;
2304                 struct sockaddr_in6 ssrc;
2305
2306                 bzero(&sdst, sizeof(sdst));
2307                 bzero(&sgw, sizeof(sgw));
2308                 bzero(&ssrc, sizeof(ssrc));
2309                 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2310                 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2311                         sizeof(struct sockaddr_in6);
2312                 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2313                 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2314                 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2315                 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
2316                            NULL, RTF_GATEWAY | RTF_HOST,
2317                            (struct sockaddr *)&ssrc);
2318         }
2319         /* finally update cached route in each socket via kpfctlinput */
2320     {
2321         struct sockaddr_in6 sdst;
2322
2323         bzero(&sdst, sizeof(sdst));
2324         sdst.sin6_family = AF_INET6;
2325         sdst.sin6_len = sizeof(struct sockaddr_in6);
2326         bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2327         kpfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2328 #ifdef IPSEC
2329         key_sa_routechange((struct sockaddr *)&sdst);
2330 #endif
2331     }
2332
2333 freeit:
2334         m_freem(m);
2335         return;
2336
2337 bad:
2338         icmp6stat.icp6s_badredirect++;
2339         m_freem(m);
2340 }
2341
2342 void
2343 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt)
2344 {
2345         struct ifnet *ifp;      /* my outgoing interface */
2346         struct in6_addr *ifp_ll6;
2347         struct in6_addr *router_ll6;
2348         struct ip6_hdr *sip6;   /* m0 as struct ip6_hdr */
2349         struct mbuf *m = NULL;  /* newly allocated one */
2350         struct ip6_hdr *ip6;    /* m as struct ip6_hdr */
2351         struct nd_redirect *nd_rd;
2352         size_t maxlen;
2353         u_char *p;
2354         struct ifnet *outif = NULL;
2355         struct sockaddr_in6 src_sa;
2356
2357         icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0);
2358
2359         /* if we are not router, we don't send icmp6 redirect */
2360         if (!ip6_forwarding || ip6_accept_rtadv)
2361                 goto fail;
2362
2363         /* sanity check */
2364         if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
2365                 goto fail;
2366
2367         /*
2368          * Address check:
2369          *  the source address must identify a neighbor, and
2370          *  the destination address must not be a multicast address
2371          *  [RFC 2461, sec 8.2]
2372          */
2373         sip6 = mtod(m0, struct ip6_hdr *);
2374         bzero(&src_sa, sizeof(src_sa));
2375         src_sa.sin6_family = AF_INET6;
2376         src_sa.sin6_len = sizeof(src_sa);
2377         src_sa.sin6_addr = sip6->ip6_src;
2378         /* we don't currently use sin6_scope_id, but eventually use it */
2379         if (in6_addr2zoneid(ifp, &sip6->ip6_src, &src_sa.sin6_scope_id))
2380                 goto fail;
2381         if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2382                 goto fail;
2383         if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2384                 goto fail;      /* what should we do here? */
2385
2386         /* rate limit */
2387         if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2388                 goto fail;
2389
2390         /*
2391          * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2392          * we almost always ask for an mbuf cluster for simplicity.
2393          * (MHLEN < IPV6_MMTU is almost always true)
2394          */
2395 #if IPV6_MMTU >= MCLBYTES
2396 # error assumption failed about IPV6_MMTU and MCLBYTES
2397 #endif
2398         m = m_getb(IPV6_MMTU, M_NOWAIT, MT_HEADER, M_PKTHDR);
2399         if (!m)
2400                 goto fail;
2401         m->m_len = 0;
2402         maxlen = M_TRAILINGSPACE(m);
2403         maxlen = min(IPV6_MMTU, maxlen);
2404         /* just for safety */
2405         if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2406             ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2407                 goto fail;
2408         }
2409
2410         {
2411                 /* get ip6 linklocal address for ifp(my outgoing interface). */
2412                 struct in6_ifaddr *ia;
2413                 if ((ia = in6ifa_ifpforlinklocal(ifp,
2414                                                  IN6_IFF_NOTREADY|
2415                                                  IN6_IFF_ANYCAST)) == NULL)
2416                         goto fail;
2417                 ifp_ll6 = &ia->ia_addr.sin6_addr;
2418         }
2419
2420         /* get ip6 linklocal address for the router. */
2421         if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2422                 struct sockaddr_in6 *sin6;
2423                 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2424                 router_ll6 = &sin6->sin6_addr;
2425                 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2426                         router_ll6 = NULL;
2427         } else
2428                 router_ll6 = NULL;
2429
2430         /* ip6 */
2431         ip6 = mtod(m, struct ip6_hdr *);
2432         ip6->ip6_flow = 0;
2433         ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2434         ip6->ip6_vfc |= IPV6_VERSION;
2435         /* ip6->ip6_plen will be set later */
2436         ip6->ip6_nxt = IPPROTO_ICMPV6;
2437         ip6->ip6_hlim = 255;
2438         /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2439         bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2440         bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2441
2442         /* ND Redirect */
2443         nd_rd = (struct nd_redirect *)(ip6 + 1);
2444         nd_rd->nd_rd_type = ND_REDIRECT;
2445         nd_rd->nd_rd_code = 0;
2446         nd_rd->nd_rd_reserved = 0;
2447         if (rt->rt_flags & RTF_GATEWAY) {
2448                 /*
2449                  * nd_rd->nd_rd_target must be a link-local address in
2450                  * better router cases.
2451                  */
2452                 if (!router_ll6)
2453                         goto fail;
2454                 bcopy(router_ll6, &nd_rd->nd_rd_target,
2455                       sizeof(nd_rd->nd_rd_target));
2456                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2457                       sizeof(nd_rd->nd_rd_dst));
2458         } else {
2459                 /* make sure redtgt == reddst */
2460                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2461                       sizeof(nd_rd->nd_rd_target));
2462                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2463                       sizeof(nd_rd->nd_rd_dst));
2464         }
2465
2466         p = (u_char *)(nd_rd + 1);
2467
2468         if (!router_ll6)
2469                 goto nolladdropt;
2470
2471         {
2472                 /* target lladdr option */
2473                 struct rtentry *rt_router = NULL;
2474                 int len;
2475                 struct sockaddr_dl *sdl;
2476                 struct nd_opt_hdr *nd_opt;
2477                 char *lladdr;
2478
2479                 rt_router = nd6_lookup(router_ll6, 0, ifp);
2480                 if (!rt_router)
2481                         goto nolladdropt;
2482                 len = sizeof(*nd_opt) + ifp->if_addrlen;
2483                 len = (len + 7) & ~7;   /* round by 8 */
2484                 /* safety check */
2485                 if (len + (p - (u_char *)ip6) > maxlen)
2486                         goto nolladdropt;
2487                 if (!(rt_router->rt_flags & RTF_GATEWAY) &&
2488                     (rt_router->rt_flags & RTF_LLINFO) &&
2489                     (rt_router->rt_gateway->sa_family == AF_LINK) &&
2490                     (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
2491                     sdl->sdl_alen) {
2492                         nd_opt = (struct nd_opt_hdr *)p;
2493                         nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2494                         nd_opt->nd_opt_len = len >> 3;
2495                         lladdr = (char *)(nd_opt + 1);
2496                         bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
2497                         p += len;
2498                 }
2499         }
2500 nolladdropt:;
2501
2502         m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2503
2504         /* just to be safe */
2505 #ifdef M_DECRYPTED      /*not openbsd*/
2506         if (m0->m_flags & M_DECRYPTED)
2507                 goto noredhdropt;
2508 #endif
2509         if (p - (u_char *)ip6 > maxlen)
2510                 goto noredhdropt;
2511
2512     {
2513         /* redirected header option */
2514         int len;
2515         struct nd_opt_rd_hdr *nd_opt_rh;
2516
2517         /*
2518          * compute the maximum size for icmp6 redirect header option.
2519          * XXX room for auth header?
2520          */
2521         len = maxlen - (p - (u_char *)ip6);
2522         len &= ~7;
2523
2524         /* This is just for simplicity. */
2525         if (m0->m_pkthdr.len != m0->m_len) {
2526                 if (m0->m_next) {
2527                         m_freem(m0->m_next);
2528                         m0->m_next = NULL;
2529                 }
2530                 m0->m_pkthdr.len = m0->m_len;
2531         }
2532
2533         /*
2534          * Redirected header option spec (RFC2461 4.6.3) talks nothing
2535          * about padding/truncate rule for the original IP packet.
2536          * From the discussion on IPv6imp in Feb 1999, the consensus was:
2537          * - "attach as much as possible" is the goal
2538          * - pad if not aligned (original size can be guessed by original
2539          *   ip6 header)
2540          * Following code adds the padding if it is simple enough,
2541          * and truncates if not.
2542          */
2543         if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2544                 panic("assumption failed in %s:%d", __FILE__, __LINE__);
2545
2546         if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2547                 /* not enough room, truncate */
2548                 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
2549         } else {
2550                 /* enough room, pad or truncate */
2551                 size_t extra;
2552
2553                 extra = m0->m_pkthdr.len % 8;
2554                 if (extra) {
2555                         /* pad if easy enough, truncate if not */
2556                         if (8 - extra <= M_TRAILINGSPACE(m0)) {
2557                                 /* pad */
2558                                 m0->m_len += (8 - extra);
2559                                 m0->m_pkthdr.len += (8 - extra);
2560                         } else {
2561                                 /* truncate */
2562                                 m0->m_pkthdr.len -= extra;
2563                                 m0->m_len -= extra;
2564                         }
2565                 }
2566                 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2567                 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
2568         }
2569
2570         nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2571         bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2572         nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2573         nd_opt_rh->nd_opt_rh_len = len >> 3;
2574         p += sizeof(*nd_opt_rh);
2575         m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2576
2577         /* connect m0 to m */
2578         m->m_next = m0;
2579         m->m_pkthdr.len = m->m_len + m0->m_len;
2580         m0 = NULL;
2581     }
2582 noredhdropt:;
2583         if (m0 != NULL) {
2584                 m_freem(m0);
2585                 m0 = NULL;
2586         }
2587
2588         /* XXX: clear embedded link IDs in the inner header */
2589         in6_clearscope(&sip6->ip6_src);
2590         in6_clearscope(&sip6->ip6_dst);
2591         in6_clearscope(&nd_rd->nd_rd_target);
2592         in6_clearscope(&nd_rd->nd_rd_dst);
2593
2594         ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2595
2596         nd_rd->nd_rd_cksum = 0;
2597         nd_rd->nd_rd_cksum
2598                 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen));
2599
2600         /* send the packet to outside... */
2601         ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2602         if (outif) {
2603                 icmp6_ifstat_inc(outif, ifs6_out_msg);
2604                 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2605         }
2606         icmp6stat.icp6s_outhist[ND_REDIRECT]++;
2607
2608         return;
2609
2610 fail:
2611         if (m)
2612                 m_freem(m);
2613         if (m0)
2614                 m_freem(m0);
2615 }
2616
2617 #ifdef HAVE_NRL_INPCB
2618 #define in6pcb          inpcb
2619 #define in6p_icmp6filt  inp_icmp6filt
2620 #endif
2621 /*
2622  * ICMPv6 socket option processing.
2623  */
2624 void
2625 icmp6_ctloutput(netmsg_t msg)
2626 {
2627         struct socket *so = msg->ctloutput.base.nm_so;
2628         struct sockopt *sopt = msg->ctloutput.nm_sopt;
2629         int error = 0;
2630         int optlen;
2631         struct inpcb *inp = so->so_pcb;
2632         int level, op, optname;
2633
2634         if (sopt) {
2635                 level = sopt->sopt_level;
2636                 op = sopt->sopt_dir;
2637                 optname = sopt->sopt_name;
2638                 optlen = sopt->sopt_valsize;
2639         } else
2640                 level = op = optname = optlen = 0;
2641
2642         if (level != IPPROTO_ICMPV6) {
2643                 error = EINVAL;
2644                 goto out;
2645         }
2646
2647         switch (op) {
2648         case PRCO_SETOPT:
2649                 switch (optname) {
2650                 case ICMP6_FILTER:
2651                     {
2652                         if (optlen != sizeof(struct icmp6_filter)) {
2653                                 error = EMSGSIZE;
2654                                 break;
2655                         }
2656                         if (inp->in6p_icmp6filt == NULL) {
2657                                 error = EINVAL;
2658                                 break;
2659                         }
2660                         error = soopt_to_kbuf(sopt, inp->in6p_icmp6filt, optlen,
2661                                 optlen);
2662                         break;
2663                     }
2664
2665                 default:
2666                         error = ENOPROTOOPT;
2667                         break;
2668                 }
2669                 break;
2670
2671         case PRCO_GETOPT:
2672                 switch (optname) {
2673                 case ICMP6_FILTER:
2674                     {
2675                         if (inp->in6p_icmp6filt == NULL) {
2676                                 error = EINVAL;
2677                                 break;
2678                         }
2679                         soopt_from_kbuf(sopt, inp->in6p_icmp6filt,
2680                                 sizeof(struct icmp6_filter));
2681                         break;
2682                     }
2683
2684                 default:
2685                         error = ENOPROTOOPT;
2686                         break;
2687                 }
2688                 break;
2689         }
2690 out:
2691         lwkt_replymsg(&msg->ctloutput.base.lmsg, error);
2692 }
2693 #ifdef HAVE_NRL_INPCB
2694 #undef in6pcb
2695 #undef in6p_icmp6filt
2696 #endif
2697
2698 #ifndef HAVE_PPSRATECHECK
2699 #ifndef timersub
2700 #define timersub(tvp, uvp, vvp)                                         \
2701         do {                                                            \
2702                 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec;          \
2703                 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec;       \
2704                 if ((vvp)->tv_usec < 0) {                               \
2705                         (vvp)->tv_sec--;                                \
2706                         (vvp)->tv_usec += 1000000;                      \
2707                 }                                                       \
2708         } while (0)
2709 #endif
2710
2711 /*
2712  * ppsratecheck(): packets (or events) per second limitation.
2713  */
2714 static int
2715 ppsratecheck(struct timeval *lasttime, int *curpps,
2716              int maxpps)        /* maximum pps allowed */
2717 {
2718         struct timeval tv, delta;
2719         int rv;
2720
2721         microtime(&tv);
2722
2723         timersub(&tv, lasttime, &delta);
2724
2725         /*
2726          * Check for 0,0 so that the message will be seen at least once.
2727          * If more than one second has passed since the last update of
2728          * lasttime, reset the counter.
2729          *
2730          * We do increment *curpps even in *curpps < maxpps case, as some may
2731          * try to use *curpps for stat purposes as well.
2732          */
2733         if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) ||
2734             delta.tv_sec >= 1) {
2735                 *lasttime = tv;
2736                 *curpps = 0;
2737                 rv = 1;
2738         } else if (maxpps < 0)
2739                 rv = 1;
2740         else if (*curpps < maxpps)
2741                 rv = 1;
2742         else
2743                 rv = 0;
2744
2745 #if 1 /* DIAGNOSTIC? */
2746         /* be careful about wrap-around */
2747         if (*curpps + 1 > *curpps)
2748                 *curpps = *curpps + 1;
2749 #else
2750         /*
2751          * assume that there's not too many calls to this function.
2752          * not sure if the assumption holds, as it depends on *caller's*
2753          * behavior, not the behavior of this function.
2754          * IMHO it is wrong to make assumption on the caller's behavior,
2755          * so the above #if is #if 1, not #ifdef DIAGNOSTIC.
2756          */
2757         *curpps = *curpps + 1;
2758 #endif
2759
2760         return (rv);
2761 }
2762 #endif
2763
2764 /*
2765  * Perform rate limit check.
2766  * Returns 0 if it is okay to send the icmp6 packet.
2767  * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2768  * limitation.
2769  *
2770  * XXX per-destination/type check necessary?
2771  */
2772 static int
2773 icmp6_ratelimit(const struct in6_addr *dst,     /* not used at this moment */
2774                 const int type,                 /* not used at this moment */
2775                 const int code)                 /* not used at this moment */
2776 {
2777         int ret;
2778
2779         ret = 0;        /* okay to send */
2780
2781         /* PPS limit */
2782         if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count,
2783             icmp6errppslim)) {
2784                 /* The packet is subject to rate limit */
2785                 ret++;
2786         }
2787
2788         return ret;
2789 }