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 #include <net/netisr2.h>
  89 #include <net/netmsg2.h>
  90
  91 #include <netinet/in.h>
  92 #include <netinet/in_var.h>
  93 #include <netinet/ip6.h>
  94 #include <netinet6/ip6_var.h>
  95 #include <netinet/icmp6.h>
  96 #include <netinet6/mld6_var.h>
  97 #include <netinet/in_pcb.h>
  98 #include <netinet6/in6_pcb.h>
  99 #include <netinet6/nd6.h>
 100 #include <netinet6/in6_ifattach.h>
 101 #include <netinet6/ip6protosw.h>
 102
 103 #ifdef IPSEC
 104 #include <netinet6/ipsec.h>
 105 #include <netproto/key/key.h>
 106 #endif
 107
 108 #ifdef FAST_IPSEC
 109 #include <netproto/ipsec/ipsec.h>
 110 #include <netproto/ipsec/key.h>
 111 #define IPSEC
 112 #endif
 113
 114 #include <net/net_osdep.h>
 115
 116 #ifdef HAVE_NRL_INPCB
 117 /* inpcb members */
 118 #define in6pcb          inpcb
 119 #define in6p_laddr      inp_laddr6
 120 #define in6p_faddr      inp_faddr6
 121 #define in6p_icmp6filt  inp_icmp6filt
 122 #define in6p_route      inp_route
 123 #define in6p_socket     inp_socket
 124 #define in6p_flags      inp_flags
 125 #define in6p_moptions   inp_moptions6
 126 #define in6p_outputopts inp_outputopts6
 127 #define in6p_ip6        inp_ipv6
 128 #define in6p_flowinfo   inp_flowinfo
 129 #define in6p_sp         inp_sp
 130 #define in6p_next       inp_next
 131 #define in6p_prev       inp_prev
 132 /* function names */
 133 #define in6_pcbdetach   in_pcbdetach
 134 #define in6_rtchange    in_rtchange
 135
 136 /*
 137  * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from
 138  * others...
 139  */
 140 #define in6p_ip6_nxt    inp_ipv6.ip6_nxt
 141 #endif
 142
 143 #define ICMP6_FASTTIMO  (hz / PR_FASTHZ)
 144
 145 /*
 146  * ppratecheck() is available, so define it here.
 147  */
 148 #define HAVE_PPSRATECHECK
 149
 150 extern struct domain inet6domain;
 151 extern struct protosw inet6sw[];
 152 extern u_char ip6_protox[];
 153
 154 struct icmp6stat icmp6stat;
 155
 156 extern struct inpcbinfo ripcbinfo;
 157 extern int icmp6errppslim;
 158 static int icmp6errpps_count = 0;
 159 static struct timeval icmp6errppslim_last;
 160 extern int icmp6_nodeinfo;
 161
 162 static void icmp6_errcount (struct icmp6errstat *, int, int);
 163 static int icmp6_rip6_input (struct mbuf **, int);
 164 static int icmp6_ratelimit (const struct in6_addr *, const int, const int);
 165 static const char *icmp6_redirect_diag (struct in6_addr *,
 166         struct in6_addr *, struct in6_addr *);
 167 #ifndef HAVE_PPSRATECHECK
 168 static int ppsratecheck (struct timeval *, int *, int);
 169 #endif
 170 static struct mbuf *ni6_input (struct mbuf *, int);
 171 static struct mbuf *ni6_nametodns (const char *, int, int);
 172 static int ni6_dnsmatch (const char *, int, const char *, int);
 173 static int ni6_addrs (struct icmp6_nodeinfo *, struct mbuf *,
 174                           struct ifnet **, char *);
 175 static int ni6_store_addrs (struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
 176                                 struct ifnet *, int);
 177 static int icmp6_notify_error (struct mbuf *, int, int, int);
 178
 179 static void                     icmp6_fasttimo(void *);
 180 static void                     icmp6_fasttimo_dispatch(netmsg_t);
 181
 182 #ifdef COMPAT_RFC1885
 183 static struct route_in6 icmp6_reflect_rt;
 184 #endif
 185
 186 static struct callout           icmp6_fasttimo_ch;
 187 static struct netmsg_base       icmp6_fasttimo_nmsg;
 188
 189 void
 190 icmp6_init(void)
 191 {
 192
 193         mld6_init();
 194
 195         callout_init_mp(&icmp6_fasttimo_ch);
 196         netmsg_init(&icmp6_fasttimo_nmsg, NULL, &netisr_adone_rport,
 197             MSGF_PRIORITY, icmp6_fasttimo_dispatch);
 198
 199         callout_reset_bycpu(&icmp6_fasttimo_ch, ICMP6_FASTTIMO,
 200             icmp6_fasttimo, NULL, 0);
 201 }
 202
 203 static void
 204 icmp6_errcount(struct icmp6errstat *stat, int type, int code)
 205 {
 206         switch (type) {
 207         case ICMP6_DST_UNREACH:
 208                 switch (code) {
 209                 case ICMP6_DST_UNREACH_NOROUTE:
 210                         stat->icp6errs_dst_unreach_noroute++;
 211                         return;
 212                 case ICMP6_DST_UNREACH_ADMIN:
 213                         stat->icp6errs_dst_unreach_admin++;
 214                         return;
 215                 case ICMP6_DST_UNREACH_BEYONDSCOPE:
 216                         stat->icp6errs_dst_unreach_beyondscope++;
 217                         return;
 218                 case ICMP6_DST_UNREACH_ADDR:
 219                         stat->icp6errs_dst_unreach_addr++;
 220                         return;
 221                 case ICMP6_DST_UNREACH_NOPORT:
 222                         stat->icp6errs_dst_unreach_noport++;
 223                         return;
 224                 }
 225                 break;
 226         case ICMP6_PACKET_TOO_BIG:
 227                 stat->icp6errs_packet_too_big++;
 228                 return;
 229         case ICMP6_TIME_EXCEEDED:
 230                 switch (code) {
 231                 case ICMP6_TIME_EXCEED_TRANSIT:
 232                         stat->icp6errs_time_exceed_transit++;
 233                         return;
 234                 case ICMP6_TIME_EXCEED_REASSEMBLY:
 235                         stat->icp6errs_time_exceed_reassembly++;
 236                         return;
 237                 }
 238                 break;
 239         case ICMP6_PARAM_PROB:
 240                 switch (code) {
 241                 case ICMP6_PARAMPROB_HEADER:
 242                         stat->icp6errs_paramprob_header++;
 243                         return;
 244                 case ICMP6_PARAMPROB_NEXTHEADER:
 245                         stat->icp6errs_paramprob_nextheader++;
 246                         return;
 247                 case ICMP6_PARAMPROB_OPTION:
 248                         stat->icp6errs_paramprob_option++;
 249                         return;
 250                 }
 251                 break;
 252         case ND_REDIRECT:
 253                 stat->icp6errs_redirect++;
 254                 return;
 255         }
 256         stat->icp6errs_unknown++;
 257 }
 258
 259 /*
 260  * Generate an error packet of type error in response to bad IP6 packet.
 261  */
 262 void
 263 icmp6_error(struct mbuf *m, int type, int code, int param)
 264 {
 265         struct ip6_hdr *oip6, *nip6;
 266         struct icmp6_hdr *icmp6;
 267         u_int preplen;
 268         int off;
 269         int nxt;
 270
 271         icmp6stat.icp6s_error++;
 272
 273         /* count per-type-code statistics */
 274         icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code);
 275
 276 #ifdef M_DECRYPTED      /*not openbsd*/
 277         if (m->m_flags & M_DECRYPTED) {
 278                 icmp6stat.icp6s_canterror++;
 279                 goto freeit;
 280         }
 281 #endif
 282
 283 #ifndef PULLDOWN_TEST
 284         IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
 285 #else
 286         if (m->m_len < sizeof(struct ip6_hdr)) {
 287                 m = m_pullup(m, sizeof(struct ip6_hdr));
 288                 if (m == NULL)
 289                         return;
 290         }
 291 #endif
 292         oip6 = mtod(m, struct ip6_hdr *);
 293
 294         /*
 295          * Multicast destination check. For unrecognized option errors,
 296          * this check has already done in ip6_unknown_opt(), so we can
 297          * check only for other errors.
 298          */
 299         if ((m->m_flags & (M_BCAST|M_MCAST) ||
 300              IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
 301             (type != ICMP6_PACKET_TOO_BIG &&
 302              (type != ICMP6_PARAM_PROB ||
 303               code != ICMP6_PARAMPROB_OPTION)))
 304                 goto freeit;
 305
 306         /* Source address check. XXX: the case of anycast source? */
 307         if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
 308             IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
 309                 goto freeit;
 310
 311         /*
 312          * If we are about to send ICMPv6 against ICMPv6 error/redirect,
 313          * don't do it.
 314          */
 315         nxt = -1;
 316         off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
 317         if (off >= 0 && nxt == IPPROTO_ICMPV6) {
 318                 struct icmp6_hdr *icp;
 319
 320 #ifndef PULLDOWN_TEST
 321                 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
 322                 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
 323 #else
 324                 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
 325                         sizeof(*icp));
 326                 if (icp == NULL) {
 327                         icmp6stat.icp6s_tooshort++;
 328                         return;
 329                 }
 330 #endif
 331                 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
 332                     icp->icmp6_type == ND_REDIRECT) {
 333                         /*
 334                          * ICMPv6 error
 335                          * Special case: for redirect (which is
 336                          * informational) we must not send icmp6 error.
 337                          */
 338                         icmp6stat.icp6s_canterror++;
 339                         goto freeit;
 340                 } else {
 341                         /* ICMPv6 informational - send the error */
 342                 }
 343         } else {
 344                 /* non-ICMPv6 - send the error */
 345         }
 346
 347         oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
 348
 349         /* Finally, do rate limitation check. */
 350         if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
 351                 icmp6stat.icp6s_toofreq++;
 352                 goto freeit;
 353         }
 354
 355         /*
 356          * OK, ICMP6 can be generated.
 357          */
 358
 359         if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
 360                 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
 361
 362         preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
 363         M_PREPEND(m, preplen, M_NOWAIT);
 364         if (m && m->m_len < preplen)
 365                 m = m_pullup(m, preplen);
 366         if (m == NULL) {
 367                 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
 368                 return;
 369         }
 370
 371         nip6 = mtod(m, struct ip6_hdr *);
 372         nip6->ip6_src  = oip6->ip6_src;
 373         nip6->ip6_dst  = oip6->ip6_dst;
 374
 375         in6_clearscope(&oip6->ip6_src);
 376         in6_clearscope(&oip6->ip6_dst);
 377
 378         icmp6 = (struct icmp6_hdr *)(nip6 + 1);
 379         icmp6->icmp6_type = type;
 380         icmp6->icmp6_code = code;
 381         icmp6->icmp6_pptr = htonl((u_int32_t)param);
 382
 383         /*
 384          * icmp6_reflect() is designed to be in the input path.
 385          * icmp6_error() can be called from both input and outut path,
 386          * and if we are in output path rcvif could contain bogus value.
 387          * clear m->m_pkthdr.rcvif for safety, we should have enough scope
 388          * information in ip header (nip6).
 389          */
 390         m->m_pkthdr.rcvif = NULL;
 391
 392         icmp6stat.icp6s_outhist[type]++;
 393         icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
 394
 395         return;
 396
 397 freeit:
 398         /*
 399          * If we can't tell wheter or not we can generate ICMP6, free it.
 400          */
 401         m_freem(m);
 402 }
 403
 404 /*
 405  * Process a received ICMP6 message.
 406  */
 407 int
 408 icmp6_input(struct mbuf **mp, int *offp, int proto)
 409 {
 410         struct mbuf *m = *mp, *n;
 411         struct ip6_hdr *ip6, *nip6;
 412         struct icmp6_hdr *icmp6, *nicmp6;
 413         int off = *offp;
 414         int icmp6len = m->m_pkthdr.len - *offp;
 415         int code, sum, noff;
 416
 417 #ifndef PULLDOWN_TEST
 418         IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
 419         /* m might change if M_LOOP.  So, call mtod after this */
 420 #endif
 421
 422         /*
 423          * Locate icmp6 structure in mbuf, and check
 424          * that not corrupted and of at least minimum length
 425          */
 426
 427         ip6 = mtod(m, struct ip6_hdr *);
 428         if (icmp6len < sizeof(struct icmp6_hdr)) {
 429                 icmp6stat.icp6s_tooshort++;
 430                 goto freeit;
 431         }
 432
 433         /*
 434          * calculate the checksum
 435          */
 436 #ifndef PULLDOWN_TEST
 437         icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
 438 #else
 439         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
 440         if (icmp6 == NULL) {
 441                 icmp6stat.icp6s_tooshort++;
 442                 return IPPROTO_DONE;
 443         }
 444 #endif
 445         code = icmp6->icmp6_code;
 446
 447         if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
 448                 nd6log((LOG_ERR,
 449                     "ICMP6 checksum error(%d|%x) %s\n",
 450                     icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src)));
 451                 icmp6stat.icp6s_checksum++;
 452                 goto freeit;
 453         }
 454
 455         icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
 456         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
 457         if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
 458                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
 459
 460         switch (icmp6->icmp6_type) {
 461         case ICMP6_DST_UNREACH:
 462                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
 463                 switch (code) {
 464                 case ICMP6_DST_UNREACH_NOROUTE:
 465                         code = PRC_UNREACH_NET;
 466                         break;
 467                 case ICMP6_DST_UNREACH_ADMIN:
 468                         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
 469                         code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
 470                         break;
 471                 case ICMP6_DST_UNREACH_ADDR:
 472                         code = PRC_HOSTDEAD;
 473                         break;
 474 #ifdef COMPAT_RFC1885
 475                 case ICMP6_DST_UNREACH_NOTNEIGHBOR:
 476                         code = PRC_UNREACH_SRCFAIL;
 477                         break;
 478 #else
 479                 case ICMP6_DST_UNREACH_BEYONDSCOPE:
 480                         /* I mean "source address was incorrect." */
 481                         code = PRC_PARAMPROB;
 482                         break;
 483 #endif
 484                 case ICMP6_DST_UNREACH_NOPORT:
 485                         code = PRC_UNREACH_PORT;
 486                         break;
 487                 default:
 488                         goto badcode;
 489                 }
 490                 goto deliver;
 491                 break;
 492
 493         case ICMP6_PACKET_TOO_BIG:
 494                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
 495                 if (code != 0)
 496                         goto badcode;
 497
 498                 code = PRC_MSGSIZE;
 499
 500                 /*
 501                  * Updating the path MTU will be done after examining
 502                  * intermediate extension headers.
 503                  */
 504                 goto deliver;
 505                 break;
 506
 507         case ICMP6_TIME_EXCEEDED:
 508                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
 509                 switch (code) {
 510                 case ICMP6_TIME_EXCEED_TRANSIT:
 511                 case ICMP6_TIME_EXCEED_REASSEMBLY:
 512                         code += PRC_TIMXCEED_INTRANS;
 513                         break;
 514                 default:
 515                         goto badcode;
 516                 }
 517                 goto deliver;
 518                 break;
 519
 520         case ICMP6_PARAM_PROB:
 521                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
 522                 switch (code) {
 523                 case ICMP6_PARAMPROB_NEXTHEADER:
 524                         code = PRC_UNREACH_PROTOCOL;
 525                         break;
 526                 case ICMP6_PARAMPROB_HEADER:
 527                 case ICMP6_PARAMPROB_OPTION:
 528                         code = PRC_PARAMPROB;
 529                         break;
 530                 default:
 531                         goto badcode;
 532                 }
 533                 goto deliver;
 534                 break;
 535
 536         case ICMP6_ECHO_REQUEST:
 537                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
 538                 if (code != 0)
 539                         goto badcode;
 540                 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
 541                         /* Give up remote */
 542                         break;
 543                 }
 544                 if ((n->m_flags & M_EXT) ||
 545                     n->m_len < off + sizeof(struct icmp6_hdr)) {
 546                         struct mbuf *n0 = n;
 547                         const int maxlen = sizeof(*nip6) + sizeof(*nicmp6);
 548                         int n0len;
 549
 550                         /*
 551                          * Prepare an internal mbuf. m_pullup() doesn't
 552                          * always copy the length we specified.
 553                          */
 554                         if (maxlen >= MCLBYTES) {
 555                                 /* Give up remote */
 556                                 m_freem(n0);
 557                                 break;
 558                         }
 559                         n = m_getb(maxlen, M_NOWAIT, n0->m_type, M_PKTHDR);
 560                         if (n == NULL) {
 561                                 /* Give up remote */
 562                                 m_freem(n0);
 563                                 break;
 564                         }
 565                         n0len = n0->m_pkthdr.len;       /* save for use below */
 566                         M_MOVE_PKTHDR(n, n0);
 567                         /*
 568                          * Copy IPv6 and ICMPv6 only.
 569                          */
 570                         nip6 = mtod(n, struct ip6_hdr *);
 571                         bcopy(ip6, nip6, sizeof(struct ip6_hdr));
 572                         nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
 573                         bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
 574                         noff = sizeof(struct ip6_hdr);
 575                         /* new mbuf contains only ipv6+icmpv6 headers */
 576                         n->m_len = noff + sizeof(struct icmp6_hdr);
 577                         /*
 578                          * Adjust mbuf. ip6_plen will be adjusted in
 579                          * ip6_output().
 580                          */
 581                         m_adj(n0, off + sizeof(struct icmp6_hdr));
 582                         /* recalculate complete packet size */
 583                         n->m_pkthdr.len = n0len + (noff - off);
 584                         n->m_next = n0;
 585                 } else {
 586                         nip6 = mtod(n, struct ip6_hdr *);
 587                         nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off);
 588                         noff = off;
 589                 }
 590                 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
 591                 nicmp6->icmp6_code = 0;
 592                 if (n) {
 593                         icmp6stat.icp6s_reflect++;
 594                         icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
 595                         icmp6_reflect(n, noff);
 596                 }
 597                 break;
 598
 599         case ICMP6_ECHO_REPLY:
 600                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
 601                 if (code != 0)
 602                         goto badcode;
 603                 break;
 604
 605         case MLD_LISTENER_QUERY:
 606         case MLD_LISTENER_REPORT:
 607                 if (icmp6len < sizeof(struct mld_hdr))
 608                         goto badlen;
 609                 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */
 610                         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
 611                 else
 612                         icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
 613                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 614                         /* give up local */
 615                         mld6_input(m, off);
 616                         m = NULL;
 617                         goto freeit;
 618                 }
 619                 mld6_input(n, off);
 620                 /* m stays. */
 621                 break;
 622
 623         case MLD_LISTENER_DONE:
 624                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
 625                 if (icmp6len < sizeof(struct mld_hdr))  /* necessary? */
 626                         goto badlen;
 627                 break;          /* nothing to be done in kernel */
 628
 629         case MLD_MTRACE_RESP:
 630         case MLD_MTRACE:
 631                 /* XXX: these two are experimental.  not officially defind. */
 632                 /* XXX: per-interface statistics? */
 633                 break;          /* just pass it to applications */
 634
 635         case ICMP6_WRUREQUEST:  /* ICMP6_FQDN_QUERY */
 636             {
 637                 enum { WRU, FQDN } mode;
 638
 639                 if (!icmp6_nodeinfo)
 640                         break;
 641
 642                 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
 643                         mode = WRU;
 644                 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
 645                         mode = FQDN;
 646                 else
 647                         goto badlen;
 648
 649 #define hostnamelen     strlen(hostname)
 650                 if (mode == FQDN) {
 651 #ifndef PULLDOWN_TEST
 652                         IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
 653                                          IPPROTO_DONE);
 654 #endif
 655                         n = m_copy(m, 0, M_COPYALL);
 656                         if (n)
 657                                 n = ni6_input(n, off);
 658                         /* XXX meaningless if n == NULL */
 659                         noff = sizeof(struct ip6_hdr);
 660                 } else {
 661                         u_char *p;
 662                         int maxlen, maxhlen;
 663
 664                         if ((icmp6_nodeinfo & 5) != 5)
 665                                 break;
 666
 667                         if (code != 0)
 668                                 goto badcode;
 669                         maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
 670                         if (maxlen >= MCLBYTES) {
 671                                 /* Give up remote */
 672                                 break;
 673                         }
 674                         n = m_getb(maxlen, M_NOWAIT, m->m_type, M_PKTHDR);
 675                         if (n == NULL) {
 676                                 /* Give up remote */
 677                                 break;
 678                         }
 679                         if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
 680                                 /*
 681                                  * Previous code did a blind M_COPY_PKTHDR
 682                                  * and said "just for rcvif".  If true, then
 683                                  * we could tolerate the dup failing (due to
 684                                  * the deep copy of the tag chain).  For now
 685                                  * be conservative and just fail.
 686                                  */
 687                                 m_free(n);
 688                                 break;
 689                         }
 690                         n->m_len = 0;
 691                         maxhlen = M_TRAILINGSPACE(n) - maxlen;
 692                         if (maxhlen > hostnamelen)
 693                                 maxhlen = hostnamelen;
 694                         /*
 695                          * Copy IPv6 and ICMPv6 only.
 696                          */
 697                         nip6 = mtod(n, struct ip6_hdr *);
 698                         bcopy(ip6, nip6, sizeof(struct ip6_hdr));
 699                         nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
 700                         bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
 701                         p = (u_char *)(nicmp6 + 1);
 702                         bzero(p, 4);
 703                         bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */
 704                         noff = sizeof(struct ip6_hdr);
 705                         n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
 706                                 sizeof(struct icmp6_hdr) + 4 + maxhlen;
 707                         nicmp6->icmp6_type = ICMP6_WRUREPLY;
 708                         nicmp6->icmp6_code = 0;
 709                 }
 710 #undef hostnamelen
 711                 if (n) {
 712                         icmp6stat.icp6s_reflect++;
 713                         icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
 714                         icmp6_reflect(n, noff);
 715                 }
 716                 break;
 717             }
 718
 719         case ICMP6_WRUREPLY:
 720                 if (code != 0)
 721                         goto badcode;
 722                 break;
 723
 724         case ND_ROUTER_SOLICIT:
 725                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
 726                 if (code != 0)
 727                         goto badcode;
 728                 if (icmp6len < sizeof(struct nd_router_solicit))
 729                         goto badlen;
 730                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 731                         /* give up local */
 732                         nd6_rs_input(m, off, icmp6len);
 733                         m = NULL;
 734                         goto freeit;
 735                 }
 736                 nd6_rs_input(n, off, icmp6len);
 737                 /* m stays. */
 738                 break;
 739
 740         case ND_ROUTER_ADVERT:
 741                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
 742                 if (code != 0)
 743                         goto badcode;
 744                 if (icmp6len < sizeof(struct nd_router_advert))
 745                         goto badlen;
 746                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 747                         /* give up local */
 748                         nd6_ra_input(m, off, icmp6len);
 749                         m = NULL;
 750                         goto freeit;
 751                 }
 752                 nd6_ra_input(n, off, icmp6len);
 753                 /* m stays. */
 754                 break;
 755
 756         case ND_NEIGHBOR_SOLICIT:
 757                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
 758                 if (code != 0)
 759                         goto badcode;
 760                 if (icmp6len < sizeof(struct nd_neighbor_solicit))
 761                         goto badlen;
 762                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 763                         /* give up local */
 764                         nd6_ns_input(m, off, icmp6len);
 765                         m = NULL;
 766                         goto freeit;
 767                 }
 768                 nd6_ns_input(n, off, icmp6len);
 769                 /* m stays. */
 770                 break;
 771
 772         case ND_NEIGHBOR_ADVERT:
 773                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
 774                 if (code != 0)
 775                         goto badcode;
 776                 if (icmp6len < sizeof(struct nd_neighbor_advert))
 777                         goto badlen;
 778                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 779                         /* give up local */
 780                         nd6_na_input(m, off, icmp6len);
 781                         m = NULL;
 782                         goto freeit;
 783                 }
 784                 nd6_na_input(n, off, icmp6len);
 785                 /* m stays. */
 786                 break;
 787
 788         case ND_REDIRECT:
 789                 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
 790                 if (code != 0)
 791                         goto badcode;
 792                 if (icmp6len < sizeof(struct nd_redirect))
 793                         goto badlen;
 794                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
 795                         /* give up local */
 796                         icmp6_redirect_input(m, off);
 797                         m = NULL;
 798                         goto freeit;
 799                 }
 800                 icmp6_redirect_input(n, off);
 801                 /* m stays. */
 802                 break;
 803
 804         case ICMP6_ROUTER_RENUMBERING:
 805                 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
 806                     code != ICMP6_ROUTER_RENUMBERING_RESULT)
 807                         goto badcode;
 808                 if (icmp6len < sizeof(struct icmp6_router_renum))
 809                         goto badlen;
 810                 break;
 811
 812         default:
 813                 nd6log((LOG_DEBUG,
 814                     "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
 815                     icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
 816                     ip6_sprintf(&ip6->ip6_dst),
 817                     m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0));
 818                 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
 819                         /* ICMPv6 error: MUST deliver it by spec... */
 820                         code = PRC_NCMDS;
 821                         /* deliver */
 822                 } else {
 823                         /* ICMPv6 informational: MUST not deliver */
 824                         break;
 825                 }
 826         deliver:
 827                 if (icmp6_notify_error(m, off, icmp6len, code)) {
 828                         /* In this case, m should've been freed. */
 829                         return (IPPROTO_DONE);
 830                 }
 831                 break;
 832
 833         badcode:
 834                 icmp6stat.icp6s_badcode++;
 835                 break;
 836
 837         badlen:
 838                 icmp6stat.icp6s_badlen++;
 839                 break;
 840         }
 841
 842         /* deliver the packet to appropriate sockets */
 843         icmp6_rip6_input(&m, *offp);
 844
 845         return IPPROTO_DONE;
 846
 847 freeit:
 848         m_freem(m);
 849         return IPPROTO_DONE;
 850 }
 851
 852 static int
 853 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code)
 854 {
 855         struct icmp6_hdr *icmp6;
 856         struct ip6_hdr *eip6;
 857         u_int32_t notifymtu;
 858         struct sockaddr_in6 icmp6src, icmp6dst;
 859
 860         if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
 861                 icmp6stat.icp6s_tooshort++;
 862                 goto freeit;
 863         }
 864 #ifndef PULLDOWN_TEST
 865         IP6_EXTHDR_CHECK(m, off,
 866                          sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
 867                          -1);
 868         icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
 869 #else
 870         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
 871                        sizeof(*icmp6) + sizeof(struct ip6_hdr));
 872         if (icmp6 == NULL) {
 873                 icmp6stat.icp6s_tooshort++;
 874                 return (-1);
 875         }
 876 #endif
 877         eip6 = (struct ip6_hdr *)(icmp6 + 1);
 878
 879         /* Detect the upper level protocol */
 880         {
 881                 u_int8_t nxt = eip6->ip6_nxt;
 882                 int eoff = off + sizeof(struct icmp6_hdr) +
 883                         sizeof(struct ip6_hdr);
 884                 struct ip6ctlparam ip6cp;
 885                 struct in6_addr *finaldst = NULL;
 886                 int icmp6type = icmp6->icmp6_type;
 887                 struct ip6_frag *fh;
 888                 struct ip6_rthdr *rth;
 889                 int rthlen;
 890
 891                 while (1) { /* XXX: should avoid infinite loop explicitly? */
 892                         struct ip6_ext *eh;
 893
 894                         switch (nxt) {
 895                         case IPPROTO_HOPOPTS:
 896                         case IPPROTO_DSTOPTS:
 897                         case IPPROTO_AH:
 898 #ifndef PULLDOWN_TEST
 899                                 IP6_EXTHDR_CHECK(m, 0,
 900                                     eoff + sizeof(struct ip6_ext), -1);
 901                                 eh = (struct ip6_ext *)
 902                                     (mtod(m, caddr_t) + eoff);
 903 #else
 904                                 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
 905                                                eoff, sizeof(*eh));
 906                                 if (eh == NULL) {
 907                                         icmp6stat.icp6s_tooshort++;
 908                                         return (-1);
 909                                 }
 910 #endif
 911
 912                                 if (nxt == IPPROTO_AH)
 913                                         eoff += (eh->ip6e_len + 2) << 2;
 914                                 else
 915                                         eoff += (eh->ip6e_len + 1) << 3;
 916                                 nxt = eh->ip6e_nxt;
 917                                 break;
 918                         case IPPROTO_ROUTING:
 919                                 /*
 920                                  * When the erroneous packet contains a
 921                                  * routing header, we should examine the
 922                                  * header to determine the final destination.
 923                                  * Otherwise, we can't properly update
 924                                  * information that depends on the final
 925                                  * destination (e.g. path MTU).
 926                                  */
 927 #ifndef PULLDOWN_TEST
 928                                 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth),
 929                                                  -1);
 930                                 rth = (struct ip6_rthdr *)(mtod(m, caddr_t)
 931                                                            + eoff);
 932 #else
 933                                 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
 934                                                eoff, sizeof(*rth));
 935                                 if (rth == NULL) {
 936                                         icmp6stat.icp6s_tooshort++;
 937                                         return (-1);
 938                                 }
 939 #endif
 940                                 rthlen = (rth->ip6r_len + 1) << 3;
 941                                 eoff += rthlen;
 942                                 nxt = rth->ip6r_nxt;
 943                                 break;
 944                         case IPPROTO_FRAGMENT:
 945 #ifndef PULLDOWN_TEST
 946                                 IP6_EXTHDR_CHECK(m, 0, eoff +
 947                                                  sizeof(struct ip6_frag),
 948                                                  -1);
 949                                 fh = (struct ip6_frag *)(mtod(m, caddr_t)
 950                                                          + eoff);
 951 #else
 952                                 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
 953                                                eoff, sizeof(*fh));
 954                                 if (fh == NULL) {
 955                                         icmp6stat.icp6s_tooshort++;
 956                                         return (-1);
 957                                 }
 958 #endif
 959                                 /*
 960                                  * Data after a fragment header is meaningless
 961                                  * unless it is the first fragment, but
 962                                  * we'll go to the notify label for path MTU
 963                                  * discovery.
 964                                  */
 965                                 if (fh->ip6f_offlg & IP6F_OFF_MASK)
 966                                         goto notify;
 967
 968                                 eoff += sizeof(struct ip6_frag);
 969                                 nxt = fh->ip6f_nxt;
 970                                 break;
 971                         default:
 972                                 /*
 973                                  * This case includes ESP and the No Next
 974                                  * Header.  In such cases going to the notify
 975                                  * label does not have any meaning
 976                                  * (i.e. pr_ctlinput will be NULL), but we go
 977                                  * anyway since we might have to update
 978                                  * path MTU information.
 979                                  */
 980                                 goto notify;
 981                         }
 982                 }
 983           notify:
 984 #ifndef PULLDOWN_TEST
 985                 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
 986 #else
 987                 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
 988                                sizeof(*icmp6) + sizeof(struct ip6_hdr));
 989                 if (icmp6 == NULL) {
 990                         icmp6stat.icp6s_tooshort++;
 991                         return (-1);
 992                 }
 993 #endif
 994
 995                 eip6 = (struct ip6_hdr *)(icmp6 + 1);
 996                 bzero(&icmp6dst, sizeof(icmp6dst));
 997                 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
 998                 icmp6dst.sin6_family = AF_INET6;
 999                 if (finaldst == NULL)
1000                         icmp6dst.sin6_addr = eip6->ip6_dst;
1001                 else
1002                         icmp6dst.sin6_addr = *finaldst;
1003                 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6dst.sin6_addr,
1004                     &icmp6dst.sin6_scope_id))
1005                         goto freeit;
1006                 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst,
1007                                    NULL, NULL)) {
1008                         /* should be impossbile */
1009                         nd6log((LOG_DEBUG,
1010                             "icmp6_notify_error: in6_embedscope failed\n"));
1011                         goto freeit;
1012                 }
1013
1014                 /*
1015                  * retrieve parameters from the inner IPv6 header, and convert
1016                  * them into sockaddr structures.
1017                  */
1018                 bzero(&icmp6src, sizeof(icmp6src));
1019                 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
1020                 icmp6src.sin6_family = AF_INET6;
1021                 icmp6src.sin6_addr = eip6->ip6_src;
1022                 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6src.sin6_addr,
1023                     &icmp6src.sin6_scope_id))
1024                         goto freeit;
1025                 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src,
1026                                    NULL, NULL)) {
1027                         /* should be impossbile */
1028                         nd6log((LOG_DEBUG,
1029                             "icmp6_notify_error: in6_embedscope failed\n"));
1030                         goto freeit;
1031                 }
1032                 icmp6src.sin6_flowinfo =
1033                         (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1034
1035                 if (finaldst == NULL)
1036                         finaldst = &eip6->ip6_dst;
1037                 ip6cp.ip6c_m = m;
1038                 ip6cp.ip6c_icmp6 = icmp6;
1039                 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1040                 ip6cp.ip6c_off = eoff;
1041                 ip6cp.ip6c_finaldst = finaldst;
1042                 ip6cp.ip6c_src = &icmp6src;
1043                 ip6cp.ip6c_nxt = nxt;
1044
1045                 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1046                         notifymtu = ntohl(icmp6->icmp6_mtu);
1047                         ip6cp.ip6c_cmdarg = (void *)&notifymtu;
1048                         icmp6_mtudisc_update(&ip6cp, 1);        /*XXX*/
1049                 }
1050
1051                 so_pr_ctlinput(
1052                         &inet6sw[ip6_protox[nxt]],
1053                         code, (struct sockaddr *)&icmp6dst, &ip6cp);
1054         }
1055         return (0);
1056
1057 freeit:
1058         m_freem(m);
1059         return (-1);
1060 }
1061
1062 void
1063 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
1064 {
1065         struct in6_addr *dst = ip6cp->ip6c_finaldst;
1066         struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1067         struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
1068         u_int mtu = ntohl(icmp6->icmp6_mtu);
1069         struct rtentry *rt = NULL;
1070         struct sockaddr_in6 sin6;
1071
1072         if (!validated)
1073                 return;
1074
1075         bzero(&sin6, sizeof(sin6));
1076         sin6.sin6_family = PF_INET6;
1077         sin6.sin6_len = sizeof(struct sockaddr_in6);
1078         sin6.sin6_addr = *dst;
1079         /* XXX normally, this won't happen */
1080         if (IN6_IS_ADDR_LINKLOCAL(dst)) {
1081                 sin6.sin6_addr.s6_addr16[1] =
1082                     htons(m->m_pkthdr.rcvif->if_index);
1083         }
1084         /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */
1085         rt = rtpurelookup((struct sockaddr *)&sin6);
1086         if (rt != NULL && (rt->rt_flags & RTF_HOST) &&
1087             !(rt->rt_rmx.rmx_locks & RTV_MTU)) {
1088                 if (mtu < IPV6_MMTU) {                          /* XXX */
1089                         rt->rt_rmx.rmx_locks |= RTV_MTU;
1090                 } else if (mtu < rt->rt_ifp->if_mtu &&
1091                            rt->rt_rmx.rmx_mtu > mtu) {
1092                         icmp6stat.icp6s_pmtuchg++;
1093                         rt->rt_rmx.rmx_mtu = mtu;
1094                 }
1095         }
1096         if (rt)
1097                 --rt->rt_refcnt;
1098 }
1099
1100 /*
1101  * Process a Node Information Query packet, based on
1102  * draft-ietf-ipngwg-icmp-name-lookups-07.
1103  *
1104  * Spec incompatibilities:
1105  * - IPv6 Subject address handling
1106  * - IPv4 Subject address handling support missing
1107  * - Proxy reply (answer even if it's not for me)
1108  * - joins NI group address at in6_ifattach() time only, does not cope
1109  *   with hostname changes by sethostname(3)
1110  */
1111 #define hostnamelen     strlen(hostname)
1112 static struct mbuf *
1113 ni6_input(struct mbuf *m, int off)
1114 {
1115         struct icmp6_nodeinfo *ni6, *nni6;
1116         struct mbuf *n = NULL;
1117         u_int16_t qtype;
1118         int subjlen;
1119         int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1120         struct ni_reply_fqdn *fqdn;
1121         int addrs;              /* for NI_QTYPE_NODEADDR */
1122         struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1123         struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */
1124         struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */
1125         struct ip6_hdr *ip6;
1126         int oldfqdn = 0;        /* if 1, return pascal string (03 draft) */
1127         char *subj = NULL;
1128         struct in6_ifaddr *ia6 = NULL;
1129
1130         ip6 = mtod(m, struct ip6_hdr *);
1131 #ifndef PULLDOWN_TEST
1132         ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1133 #else
1134         IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1135         if (ni6 == NULL) {
1136                 /* m is already reclaimed */
1137                 return NULL;
1138         }
1139 #endif
1140
1141         /*
1142          * Validate IPv6 destination address.
1143          *
1144          * The Responder must discard the Query without further processing
1145          * unless it is one of the Responder's unicast or anycast addresses, or
1146          * a link-local scope multicast address which the Responder has joined.
1147          * [icmp-name-lookups-07, Section 4.]
1148          */
1149         bzero(&sin6, sizeof(sin6));
1150         sin6.sin6_family = AF_INET6;
1151         sin6.sin6_len = sizeof(struct sockaddr_in6);
1152         bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr));
1153         /* XXX scopeid */
1154         if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) {
1155                 /* unicast/anycast, fine */
1156                 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
1157                     (icmp6_nodeinfo & 4) == 0) {
1158                         nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
1159                                 "a temporary address in %s:%d",
1160                                __FILE__, __LINE__));
1161                         goto bad;
1162                 }
1163         } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr))
1164                 ; /* link-local multicast, fine */
1165         else
1166                 goto bad;
1167
1168         /* validate query Subject field. */
1169         qtype = ntohs(ni6->ni_qtype);
1170         subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1171         switch (qtype) {
1172         case NI_QTYPE_NOOP:
1173         case NI_QTYPE_SUPTYPES:
1174                 /* 07 draft */
1175                 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1176                         break;
1177                 /* FALLTHROUGH */
1178         case NI_QTYPE_FQDN:
1179         case NI_QTYPE_NODEADDR:
1180                 switch (ni6->ni_code) {
1181                 case ICMP6_NI_SUBJ_IPV6:
1182 #if ICMP6_NI_SUBJ_IPV6 != 0
1183                 case 0:
1184 #endif
1185                         /*
1186                          * backward compatibility - try to accept 03 draft
1187                          * format, where no Subject is present.
1188                          */
1189                         if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1190                             subjlen == 0) {
1191                                 oldfqdn++;
1192                                 break;
1193                         }
1194 #if ICMP6_NI_SUBJ_IPV6 != 0
1195                         if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1196                                 goto bad;
1197 #endif
1198
1199                         if (subjlen != sizeof(sin6.sin6_addr))
1200                                 goto bad;
1201
1202                         /*
1203                          * Validate Subject address.
1204                          *
1205                          * Not sure what exactly "address belongs to the node"
1206                          * means in the spec, is it just unicast, or what?
1207                          *
1208                          * At this moment we consider Subject address as
1209                          * "belong to the node" if the Subject address equals
1210                          * to the IPv6 destination address; validation for
1211                          * IPv6 destination address should have done enough
1212                          * check for us.
1213                          *
1214                          * We do not do proxy at this moment.
1215                          */
1216                         /* m_pulldown instead of copy? */
1217                         m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1218                             subjlen, (caddr_t)&sin6.sin6_addr);
1219                         if (in6_addr2zoneid(m->m_pkthdr.rcvif,
1220                             &sin6.sin6_addr, &sin6.sin6_scope_id))
1221                                 goto bad;
1222                         in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL);
1223                         bzero(&sin6_d, sizeof(sin6_d));
1224                         sin6_d.sin6_family = AF_INET6; /* not used, actually */
1225                         sin6_d.sin6_len = sizeof(sin6_d); /* ditto */
1226                         sin6_d.sin6_addr = ip6->ip6_dst;
1227                         if (in6_addr2zoneid(m->m_pkthdr.rcvif,
1228                             &ip6->ip6_dst, &sin6_d.sin6_scope_id))
1229                                 goto bad;
1230                         in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL);
1231                         subj = (char *)&sin6;
1232                         if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d))
1233                                 break;
1234
1235                         /*
1236                          * XXX if we are to allow other cases, we should really
1237                          * be careful about scope here.
1238                          * basically, we should disallow queries toward IPv6
1239                          * destination X with subject Y, if scope(X) > scope(Y).
1240                          * if we allow scope(X) > scope(Y), it will result in
1241                          * information leakage across scope boundary.
1242                          */
1243                         goto bad;
1244
1245                 case ICMP6_NI_SUBJ_FQDN:
1246                         /*
1247                          * Validate Subject name with gethostname(3).
1248                          *
1249                          * The behavior may need some debate, since:
1250                          * - we are not sure if the node has FQDN as
1251                          *   hostname (returned by gethostname(3)).
1252                          * - the code does wildcard match for truncated names.
1253                          *   however, we are not sure if we want to perform
1254                          *   wildcard match, if gethostname(3) side has
1255                          *   truncated hostname.
1256                          */
1257                         n = ni6_nametodns(hostname, hostnamelen, 0);
1258                         if (!n || n->m_next || n->m_len == 0)
1259                                 goto bad;
1260                         IP6_EXTHDR_GET(subj, char *, m,
1261                             off + sizeof(struct icmp6_nodeinfo), subjlen);
1262                         if (subj == NULL)
1263                                 goto bad;
1264                         if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1265                                         n->m_len)) {
1266                                 goto bad;
1267                         }
1268                         m_freem(n);
1269                         n = NULL;
1270                         break;
1271
1272                 case ICMP6_NI_SUBJ_IPV4:        /* XXX: to be implemented? */
1273                 default:
1274                         goto bad;
1275                 }
1276                 break;
1277         }
1278
1279         /* refuse based on configuration.  XXX ICMP6_NI_REFUSED? */
1280         switch (qtype) {
1281         case NI_QTYPE_FQDN:
1282                 if ((icmp6_nodeinfo & 1) == 0)
1283                         goto bad;
1284                 break;
1285         case NI_QTYPE_NODEADDR:
1286                 if ((icmp6_nodeinfo & 2) == 0)
1287                         goto bad;
1288                 break;
1289         }
1290
1291         /* guess reply length */
1292         switch (qtype) {
1293         case NI_QTYPE_NOOP:
1294                 break;          /* no reply data */
1295         case NI_QTYPE_SUPTYPES:
1296                 replylen += sizeof(u_int32_t);
1297                 break;
1298         case NI_QTYPE_FQDN:
1299                 /* XXX will append an mbuf */
1300                 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1301                 break;
1302         case NI_QTYPE_NODEADDR:
1303                 addrs = ni6_addrs(ni6, m, &ifp, subj);
1304                 if ((replylen += addrs * (sizeof(struct in6_addr) +
1305                                           sizeof(u_int32_t))) > MCLBYTES)
1306                         replylen = MCLBYTES; /* XXX: will truncate pkt later */
1307                 break;
1308         default:
1309                 /*
1310                  * XXX: We must return a reply with the ICMP6 code
1311                  * `unknown Qtype' in this case. However we regard the case
1312                  * as an FQDN query for backward compatibility.
1313                  * Older versions set a random value to this field,
1314                  * so it rarely varies in the defined qtypes.
1315                  * But the mechanism is not reliable...
1316                  * maybe we should obsolete older versions.
1317                  */
1318                 qtype = NI_QTYPE_FQDN;
1319                 /* XXX will append an mbuf */
1320                 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1321                 oldfqdn++;
1322                 break;
1323         }
1324
1325         /* allocate an mbuf to reply. */
1326         if (replylen > MCLBYTES) {
1327                 /*
1328                  * XXX: should we try to allocate more? But MCLBYTES
1329                  * is probably much larger than IPV6_MMTU...
1330                  */
1331                 goto bad;
1332         }
1333         n = m_getb(replylen, M_NOWAIT, m->m_type, M_PKTHDR);
1334         if (n == NULL) {
1335                 m_freem(m);
1336                 return (NULL);
1337         }
1338         M_MOVE_PKTHDR(n, m); /* just for recvif */
1339         n->m_pkthdr.len = n->m_len = replylen;
1340
1341         /* copy mbuf header and IPv6 + Node Information base headers */
1342         bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1343         nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1344         bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1345
1346         /* qtype dependent procedure */
1347         switch (qtype) {
1348         case NI_QTYPE_NOOP:
1349                 nni6->ni_code = ICMP6_NI_SUCCESS;
1350                 nni6->ni_flags = 0;
1351                 break;
1352         case NI_QTYPE_SUPTYPES:
1353         {
1354                 u_int32_t v;
1355                 nni6->ni_code = ICMP6_NI_SUCCESS;
1356                 nni6->ni_flags = htons(0x0000); /* raw bitmap */
1357                 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1358                 v = (u_int32_t)htonl(0x0000000f);
1359                 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
1360                 break;
1361         }
1362         case NI_QTYPE_FQDN:
1363                 nni6->ni_code = ICMP6_NI_SUCCESS;
1364                 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1365                                                 sizeof(struct ip6_hdr) +
1366                                                 sizeof(struct icmp6_nodeinfo));
1367                 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1368                 fqdn->ni_fqdn_ttl = 0;  /* ditto. */
1369                 /*
1370                  * XXX do we really have FQDN in variable "hostname"?
1371                  */
1372                 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
1373                 if (n->m_next == NULL)
1374                         goto bad;
1375                 /* XXX we assume that n->m_next is not a chain */
1376                 if (n->m_next->m_next != NULL)
1377                         goto bad;
1378                 n->m_pkthdr.len += n->m_next->m_len;
1379                 break;
1380         case NI_QTYPE_NODEADDR:
1381         {
1382                 int lenlim, copied;
1383
1384                 nni6->ni_code = ICMP6_NI_SUCCESS;
1385                 n->m_pkthdr.len = n->m_len =
1386                     sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1387                 lenlim = M_TRAILINGSPACE(n);
1388                 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1389                 /* XXX: reset mbuf length */
1390                 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1391                         sizeof(struct icmp6_nodeinfo) + copied;
1392                 break;
1393         }
1394         default:
1395                 break;          /* XXX impossible! */
1396         }
1397
1398         nni6->ni_type = ICMP6_NI_REPLY;
1399         m_freem(m);
1400         return (n);
1401
1402 bad:
1403         m_freem(m);
1404         if (n)
1405                 m_freem(n);
1406         return (NULL);
1407 }
1408 #undef hostnamelen
1409
1410 /*
1411  * make a mbuf with DNS-encoded string.  no compression support.
1412  *
1413  * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1414  * treated as truncated name (two \0 at the end).  this is a wild guess.
1415  */
1416 static struct mbuf *
1417 ni6_nametodns(const char *name, int namelen,
1418               int old) /* return pascal string if non-zero */
1419 {
1420         struct mbuf *m;
1421         char *cp, *ep;
1422         const char *p, *q;
1423         int i, len, nterm;
1424
1425         if (old)
1426                 len = namelen + 1;
1427         else
1428                 len = MCLBYTES;
1429
1430         /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
1431         m = m_getb(len, M_NOWAIT, MT_DATA, 0);
1432         if (!m)
1433                 goto fail;
1434
1435         if (old) {
1436                 m->m_len = len;
1437                 *mtod(m, char *) = namelen;
1438                 bcopy(name, mtod(m, char *) + 1, namelen);
1439                 return m;
1440         } else {
1441                 m->m_len = 0;
1442                 cp = mtod(m, char *);
1443                 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1444
1445                 /* if not certain about my name, return empty buffer */
1446                 if (namelen == 0)
1447                         return m;
1448
1449                 /*
1450                  * guess if it looks like shortened hostname, or FQDN.
1451                  * shortened hostname needs two trailing "\0".
1452                  */
1453                 i = 0;
1454                 for (p = name; p < name + namelen; p++) {
1455                         if (*p && *p == '.')
1456                                 i++;
1457                 }
1458                 if (i < 2)
1459                         nterm = 2;
1460                 else
1461                         nterm = 1;
1462
1463                 p = name;
1464                 while (cp < ep && p < name + namelen) {
1465                         i = 0;
1466                         for (q = p; q < name + namelen && *q && *q != '.'; q++)
1467                                 i++;
1468                         /* result does not fit into mbuf */
1469                         if (cp + i + 1 >= ep)
1470                                 goto fail;
1471                         /*
1472                          * DNS label length restriction, RFC1035 page 8.
1473                          * "i == 0" case is included here to avoid returning
1474                          * 0-length label on "foo..bar".
1475                          */
1476                         if (i <= 0 || i >= 64)
1477                                 goto fail;
1478                         *cp++ = i;
1479                         bcopy(p, cp, i);
1480                         cp += i;
1481                         p = q;
1482                         if (p < name + namelen && *p == '.')
1483                                 p++;
1484                 }
1485                 /* termination */
1486                 if (cp + nterm >= ep)
1487                         goto fail;
1488                 while (nterm-- > 0)
1489                         *cp++ = '\0';
1490                 m->m_len = cp - mtod(m, char *);
1491                 return m;
1492         }
1493
1494         panic("should not reach here");
1495         /* NOTREACHED */
1496
1497 fail:
1498         if (m)
1499                 m_freem(m);
1500         return NULL;
1501 }
1502
1503 /*
1504  * check if two DNS-encoded string matches.  takes care of truncated
1505  * form (with \0\0 at the end).  no compression support.
1506  * XXX upper/lowercase match (see RFC2065)
1507  */
1508 static int
1509 ni6_dnsmatch(const char *a, int alen, const char *b, int blen)
1510 {
1511         const char *a0, *b0;
1512         int l;
1513
1514         /* simplest case - need validation? */
1515         if (alen == blen && bcmp(a, b, alen) == 0)
1516                 return 1;
1517
1518         a0 = a;
1519         b0 = b;
1520
1521         /* termination is mandatory */
1522         if (alen < 2 || blen < 2)
1523                 return 0;
1524         if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1525                 return 0;
1526         alen--;
1527         blen--;
1528
1529         while (a - a0 < alen && b - b0 < blen) {
1530                 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1531                         return 0;
1532
1533                 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1534                         return 0;
1535                 /* we don't support compression yet */
1536                 if (a[0] >= 64 || b[0] >= 64)
1537                         return 0;
1538
1539                 /* truncated case */
1540                 if (a[0] == 0 && a - a0 == alen - 1)
1541                         return 1;
1542                 if (b[0] == 0 && b - b0 == blen - 1)
1543                         return 1;
1544                 if (a[0] == 0 || b[0] == 0)
1545                         return 0;
1546
1547                 if (a[0] != b[0])
1548                         return 0;
1549                 l = a[0];
1550                 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1551                         return 0;
1552                 if (bcmp(a + 1, b + 1, l) != 0)
1553                         return 0;
1554
1555                 a += 1 + l;
1556                 b += 1 + l;
1557         }
1558
1559         if (a - a0 == alen && b - b0 == blen)
1560                 return 1;
1561         else
1562                 return 0;
1563 }
1564
1565 /*
1566  * calculate the number of addresses to be returned in the node info reply.
1567  */
1568 static int
1569 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp,
1570           char *subj)
1571 {
1572         const struct ifnet_array *arr;
1573         struct in6_ifaddr *ifa6;
1574         struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */
1575         int addrs = 0, addrsofif, iffound = 0;
1576         int niflags = ni6->ni_flags;
1577         int i;
1578
1579         if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1580                 switch (ni6->ni_code) {
1581                 case ICMP6_NI_SUBJ_IPV6:
1582                         if (subj == NULL) /* must be impossible... */
1583                                 return (0);
1584                         subj_ip6 = (struct sockaddr_in6 *)subj;
1585                         break;
1586                 default:
1587                         /*
1588                          * XXX: we only support IPv6 subject address for
1589                          * this Qtype.
1590                          */
1591                         return (0);
1592                 }
1593         }
1594
1595         arr = ifnet_array_get();
1596         for (i = 0; i < arr->ifnet_count; ++i) {
1597                 struct ifnet *ifp = arr->ifnet_arr[i];
1598                 struct ifaddr_container *ifac;
1599
1600                 addrsofif = 0;
1601                 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link)
1602                 {
1603                         struct ifaddr *ifa = ifac->ifa;
1604
1605                         if (ifa->ifa_addr->sa_family != AF_INET6)
1606                                 continue;
1607                         ifa6 = (struct in6_ifaddr *)ifa;
1608
1609                         if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1610                             IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr,
1611                                                &ifa6->ia_addr.sin6_addr))
1612                                 iffound = 1;
1613
1614                         /*
1615                          * IPv4-mapped addresses can only be returned by a
1616                          * Node Information proxy, since they represent
1617                          * addresses of IPv4-only nodes, which perforce do
1618                          * not implement this protocol.
1619                          * [icmp-name-lookups-07, Section 5.4]
1620                          * So we don't support NI_NODEADDR_FLAG_COMPAT in
1621                          * this function at this moment.
1622                          */
1623
1624                         /* What do we have to do about ::1? */
1625                         switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1626                         case IPV6_ADDR_SCOPE_LINKLOCAL:
1627                                 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1628                                         continue;
1629                                 break;
1630                         case IPV6_ADDR_SCOPE_SITELOCAL:
1631                                 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1632                                         continue;
1633                                 break;
1634                         case IPV6_ADDR_SCOPE_GLOBAL:
1635                                 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1636                                         continue;
1637                                 break;
1638                         default:
1639                                 continue;
1640                         }
1641
1642                         /*
1643                          * check if anycast is okay.
1644                          * XXX: just experimental.  not in the spec.
1645                          */
1646                         if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) &&
1647                             !(niflags & NI_NODEADDR_FLAG_ANYCAST))
1648                                 continue; /* we need only unicast addresses */
1649                         if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) &&
1650                             (icmp6_nodeinfo & 4) == 0) {
1651                                 continue;
1652                         }
1653                         addrsofif++; /* count the address */
1654                 }
1655                 if (iffound) {
1656                         *ifpp = ifp;
1657                         return (addrsofif);
1658                 }
1659
1660                 addrs += addrsofif;
1661         }
1662
1663         return (addrs);
1664 }
1665
1666 static int
1667 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6,
1668                 struct ifnet *ifp0, int resid)
1669 {
1670         const struct ifnet_array *arr;
1671         struct in6_ifaddr *ifa6;
1672         int copied = 0, allow_deprecated = 0;
1673         u_char *cp = (u_char *)(nni6 + 1);
1674         int niflags = ni6->ni_flags;
1675         u_int32_t ltime;
1676         int idx, idx_dep = -1;
1677
1678         if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1679                 return (0);     /* needless to copy */
1680
1681         arr = ifnet_array_get();
1682         if (ifp0 == NULL) {
1683                 idx = 0;
1684         } else {
1685                 for (idx = 0; idx < arr->ifnet_count; ++idx) {
1686                         if (arr->ifnet_arr[idx] == ifp0)
1687                                 break;
1688                 }
1689         }
1690
1691 again:
1692
1693         for (; idx < arr->ifnet_count; ++idx) {
1694                 struct ifnet *ifp = arr->ifnet_arr[idx];
1695                 struct ifaddr_container *ifac;
1696
1697                 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
1698                         struct ifaddr *ifa = ifac->ifa;
1699
1700                         if (ifa->ifa_addr->sa_family != AF_INET6)
1701                                 continue;
1702                         ifa6 = (struct in6_ifaddr *)ifa;
1703
1704                         if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) &&
1705                             allow_deprecated == 0) {
1706                                 /*
1707                                  * prefererred address should be put before
1708                                  * deprecated addresses.
1709                                  */
1710
1711                                 /* record the interface for later search */
1712                                 if (idx_dep < 0)
1713                                         idx_dep = idx;
1714
1715                                 continue;
1716                         }
1717                         else if (!(ifa6->ia6_flags & IN6_IFF_DEPRECATED) &&
1718                                  allow_deprecated != 0)
1719                                 continue; /* we now collect deprecated addrs */
1720
1721                         /* What do we have to do about ::1? */
1722                         switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1723                         case IPV6_ADDR_SCOPE_LINKLOCAL:
1724                                 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1725                                         continue;
1726                                 break;
1727                         case IPV6_ADDR_SCOPE_SITELOCAL:
1728                                 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1729                                         continue;
1730                                 break;
1731                         case IPV6_ADDR_SCOPE_GLOBAL:
1732                                 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1733                                         continue;
1734                                 break;
1735                         default:
1736                                 continue;
1737                         }
1738
1739                         /*
1740                          * check if anycast is okay.
1741                          * XXX: just experimental. not in the spec.
1742                          */
1743                         if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) &&
1744                             !(niflags & NI_NODEADDR_FLAG_ANYCAST))
1745                                 continue;
1746                         if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) &&
1747                             (icmp6_nodeinfo & 4) == 0) {
1748                                 continue;
1749                         }
1750
1751                         /* now we can copy the address */
1752                         if (resid < sizeof(struct in6_addr) +
1753                             sizeof(u_int32_t)) {
1754                                 /*
1755                                  * We give up much more copy.
1756                                  * Set the truncate flag and return.
1757                                  */
1758                                 nni6->ni_flags |=
1759                                         NI_NODEADDR_FLAG_TRUNCATE;
1760                                 return (copied);
1761                         }
1762
1763                         /*
1764                          * Set the TTL of the address.
1765                          * The TTL value should be one of the following
1766                          * according to the specification:
1767                          *
1768                          * 1. The remaining lifetime of a DHCP lease on the
1769                          *    address, or
1770                          * 2. The remaining Valid Lifetime of a prefix from
1771                          *    which the address was derived through Stateless
1772                          *    Autoconfiguration.
1773                          *
1774                          * Note that we currently do not support stateful
1775                          * address configuration by DHCPv6, so the former
1776                          * case can't happen.
1777                          */
1778                         if (ifa6->ia6_lifetime.ia6t_expire == 0)
1779                                 ltime = ND6_INFINITE_LIFETIME;
1780                         else {
1781                                 if (ifa6->ia6_lifetime.ia6t_expire >
1782                                     time_uptime)
1783                                         ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_uptime);
1784                                 else
1785                                         ltime = 0;
1786                         }
1787
1788                         bcopy(&ltime, cp, sizeof(u_int32_t));
1789                         cp += sizeof(u_int32_t);
1790
1791                         /* copy the address itself */
1792                         bcopy(&ifa6->ia_addr.sin6_addr, cp,
1793                               sizeof(struct in6_addr));
1794                         in6_clearscope((struct in6_addr *)cp); /* XXX */
1795                         cp += sizeof(struct in6_addr);
1796
1797                         resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1798                         copied += (sizeof(struct in6_addr) +
1799                                    sizeof(u_int32_t));
1800                 }
1801                 if (ifp0)       /* we need search only on the specified IF */
1802                         break;
1803         }
1804
1805         if (allow_deprecated == 0 && idx_dep >= 0) {
1806                 idx = idx_dep;
1807                 allow_deprecated = 1;
1808
1809                 goto again;
1810         }
1811
1812         return (copied);
1813 }
1814
1815 /*
1816  * XXX almost dup'ed code with rip6_input.
1817  */
1818 static int
1819 icmp6_rip6_input(struct mbuf **mp, int  off)
1820 {
1821         struct mbuf *m = *mp;
1822         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1823         struct in6pcb *in6p;
1824         struct in6pcb *last = NULL;
1825         struct sockaddr_in6 fromsa;
1826         struct icmp6_hdr *icmp6;
1827         struct mbuf *opts = NULL;
1828
1829 #ifndef PULLDOWN_TEST
1830         /* this is assumed to be safe. */
1831         icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1832 #else
1833         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1834         if (icmp6 == NULL) {
1835                 /* m is already reclaimed */
1836                 return IPPROTO_DONE;
1837         }
1838 #endif
1839
1840         bzero(&fromsa, sizeof(fromsa));
1841         fromsa.sin6_len = sizeof(struct sockaddr_in6);
1842         fromsa.sin6_family = AF_INET6;
1843         /* KAME hack: recover scopeid */
1844         in6_recoverscope(&fromsa, &ip6->ip6_src, m->m_pkthdr.rcvif);
1845
1846         LIST_FOREACH(in6p, &ripcbinfo.pcblisthead, inp_list)
1847         {
1848                 if (in6p->inp_flags & INP_PLACEMARKER)
1849                         continue;
1850                 if (!INP_ISIPV6(in6p))
1851                         continue;
1852                 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
1853                         continue;
1854                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
1855                    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
1856                         continue;
1857                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
1858                    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
1859                         continue;
1860                 if (in6p->in6p_icmp6filt
1861                     && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
1862                                  in6p->in6p_icmp6filt))
1863                         continue;
1864                 if (last) {
1865                         struct socket *so;
1866                         struct mbuf *n;
1867
1868                         if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
1869                                 if (last->in6p_flags & IN6P_CONTROLOPTS)
1870                                         ip6_savecontrol(last, &opts, ip6, n);
1871                                 /* strip intermediate headers */
1872                                 m_adj(n, off);
1873                                 so = last->in6p_socket;
1874                                 lwkt_gettoken(&so->so_rcv.ssb_token);
1875                                 if (ssb_appendaddr(&so->so_rcv,
1876                                     (struct sockaddr *)&fromsa, n, opts) == 0) {
1877                                         /* should notify about lost packet */
1878                                         m_freem(n);
1879                                         if (opts)
1880                                                 m_freem(opts);
1881                                 } else {
1882                                         sorwakeup(so);
1883                                 }
1884                                 lwkt_reltoken(&so->so_rcv.ssb_token);
1885                                 opts = NULL;
1886                         }
1887                 }
1888                 last = in6p;
1889         }
1890         if (last) {
1891                 struct socket *so;
1892
1893                 if (last->in6p_flags & IN6P_CONTROLOPTS)
1894                         ip6_savecontrol(last, &opts, ip6, m);
1895                 /* strip intermediate headers */
1896                 m_adj(m, off);
1897                 so = last->in6p_socket;
1898                 lwkt_gettoken(&so->so_rcv.ssb_token);
1899                 if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *)&fromsa,
1900                     m, opts) == 0) {
1901                         m_freem(m);
1902                         if (opts)
1903                                 m_freem(opts);
1904                 } else {
1905                         sorwakeup(so);
1906                 }
1907                 lwkt_reltoken(&so->so_rcv.ssb_token);
1908         } else {
1909                 m_freem(m);
1910                 ip6stat.ip6s_delivered--;
1911         }
1912         return IPPROTO_DONE;
1913 }
1914
1915 /*
1916  * Reflect the ip6 packet back to the source.
1917  * OFF points to the icmp6 header, counted from the top of the mbuf.
1918  */
1919 void
1920 icmp6_reflect(struct mbuf *m, size_t off)
1921 {
1922         struct ip6_hdr *ip6;
1923         struct icmp6_hdr *icmp6;
1924         struct in6_ifaddr *ia;
1925         struct in6_addr t, *src = NULL;
1926         int plen;
1927         int type, code;
1928         struct ifnet *outif = NULL;
1929         struct sockaddr_in6 sa6_src, sa6_dst;
1930 #ifdef COMPAT_RFC1885
1931         int mtu = IPV6_MMTU;
1932         struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
1933 #endif
1934
1935         /* too short to reflect */
1936         if (off < sizeof(struct ip6_hdr)) {
1937                 nd6log((LOG_DEBUG,
1938                     "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
1939                     (u_long)off, (u_long)sizeof(struct ip6_hdr),
1940                     __FILE__, __LINE__));
1941                 goto bad;
1942         }
1943
1944         /*
1945          * If there are extra headers between IPv6 and ICMPv6, strip
1946          * off that header first.
1947          */
1948 #ifdef DIAGNOSTIC
1949         if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
1950                 panic("assumption failed in icmp6_reflect");
1951 #endif
1952         if (off > sizeof(struct ip6_hdr)) {
1953                 size_t l;
1954                 struct ip6_hdr nip6;
1955
1956                 l = off - sizeof(struct ip6_hdr);
1957                 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
1958                 m_adj(m, l);
1959                 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
1960                 if (m->m_len < l) {
1961                         if ((m = m_pullup(m, l)) == NULL)
1962                                 return;
1963                 }
1964                 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
1965         } else /* off == sizeof(struct ip6_hdr) */ {
1966                 size_t l;
1967                 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
1968                 if (m->m_len < l) {
1969                         if ((m = m_pullup(m, l)) == NULL)
1970                                 return;
1971                 }
1972         }
1973         plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
1974         ip6 = mtod(m, struct ip6_hdr *);
1975         ip6->ip6_nxt = IPPROTO_ICMPV6;
1976         icmp6 = (struct icmp6_hdr *)(ip6 + 1);
1977         type = icmp6->icmp6_type; /* keep type for statistics */
1978         code = icmp6->icmp6_code; /* ditto. */
1979
1980         t = ip6->ip6_dst;
1981         /*
1982          * ip6_input() drops a packet if its src is multicast.
1983          * So, the src is never multicast.
1984          */
1985         ip6->ip6_dst = ip6->ip6_src;
1986
1987         /*
1988          * XXX: make sure to embed scope zone information, using
1989          * already embedded IDs or the received interface (if any).
1990          * Note that rcvif may be NULL.
1991          * TODO: scoped routing case (XXX).
1992          */
1993         bzero(&sa6_src, sizeof(sa6_src));
1994         sa6_src.sin6_family = AF_INET6;
1995         sa6_src.sin6_len = sizeof(sa6_src);
1996         sa6_src.sin6_addr = ip6->ip6_dst;
1997         in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif);
1998         in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL);
1999         bzero(&sa6_dst, sizeof(sa6_dst));
2000         sa6_dst.sin6_family = AF_INET6;
2001         sa6_dst.sin6_len = sizeof(sa6_dst);
2002         sa6_dst.sin6_addr = t;
2003         in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif);
2004         in6_embedscope(&t, &sa6_dst, NULL, NULL);
2005
2006 #ifdef COMPAT_RFC1885
2007         /*
2008          * xxx guess MTU
2009          * RFC 1885 requires that echo reply should be truncated if it
2010          * does not fit in with (return) path MTU, but the description was
2011          * removed in the new spec.
2012          */
2013         if (icmp6_reflect_rt.ro_rt == 0 ||
2014             ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) {
2015                 if (icmp6_reflect_rt.ro_rt) {
2016                         RTFREE(icmp6_reflect_rt.ro_rt);
2017                         icmp6_reflect_rt.ro_rt = 0;
2018                 }
2019                 bzero(sin6, sizeof(*sin6));
2020                 sin6->sin6_family = PF_INET6;
2021                 sin6->sin6_len = sizeof(struct sockaddr_in6);
2022                 sin6->sin6_addr = ip6->ip6_dst;
2023
2024                 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt,
2025                             RTF_PRCLONING);
2026         }
2027
2028         if (icmp6_reflect_rt.ro_rt == 0)
2029                 goto bad;
2030
2031         if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST)
2032             && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu)
2033                 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu;
2034
2035         if (mtu < m->m_pkthdr.len) {
2036                 plen -= (m->m_pkthdr.len - mtu);
2037                 m_adj(m, mtu - m->m_pkthdr.len);
2038         }
2039 #endif
2040         /*
2041          * If the incoming packet was addressed directly to us(i.e. unicast),
2042          * use dst as the src for the reply.
2043          * The IN6_IFF_NOTREADY case would be VERY rare, but is possible
2044          * (for example) when we encounter an error while forwarding procedure
2045          * destined to a duplicated address of ours.
2046          */
2047         for (ia = in6_ifaddr; ia; ia = ia->ia_next)
2048                 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) &&
2049                     (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) {
2050                         src = &t;
2051                         break;
2052                 }
2053         if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) {
2054                 /*
2055                  * This is the case if the dst is our link-local address
2056                  * and the sender is also ourselves.
2057                  */
2058                 src = &t;
2059         }
2060
2061         if (src == NULL) {
2062                 int e;
2063                 struct route_in6 ro;
2064
2065                 /*
2066                  * This case matches to multicasts, our anycast, or unicasts
2067                  * that we do not own.  Select a source address based on the
2068                  * source address of the erroneous packet.
2069                  */
2070                 bzero(&ro, sizeof(ro));
2071                 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e, NULL);
2072                 if (ro.ro_rt)
2073                         RTFREE(ro.ro_rt); /* XXX: we could use this */
2074                 if (src == NULL) {
2075                         nd6log((LOG_DEBUG,
2076                             "icmp6_reflect: source can't be determined: "
2077                             "dst=%s, error=%d\n",
2078                             ip6_sprintf(&sa6_src.sin6_addr), e));
2079                         goto bad;
2080                 }
2081         }
2082
2083         ip6->ip6_src = *src;
2084
2085         ip6->ip6_flow = 0;
2086         ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2087         ip6->ip6_vfc |= IPV6_VERSION;
2088         ip6->ip6_nxt = IPPROTO_ICMPV6;
2089         if (m->m_pkthdr.rcvif) {
2090                 /* XXX: This may not be the outgoing interface */
2091                 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
2092                 if (ip6->ip6_hlim < ip6_minhlim)
2093                         ip6->ip6_hlim = ip6_minhlim;
2094         } else {
2095                 ip6->ip6_hlim = ip6_defhlim;
2096         }
2097
2098         icmp6->icmp6_cksum = 0;
2099         icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2100                                         sizeof(struct ip6_hdr), plen);
2101
2102         /*
2103          * XXX option handling
2104          */
2105
2106         m->m_flags &= ~(M_BCAST|M_MCAST);
2107
2108 #ifdef COMPAT_RFC1885
2109         ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL);
2110 #else
2111         ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2112 #endif
2113         if (outif)
2114                 icmp6_ifoutstat_inc(outif, type, code);
2115
2116         return;
2117
2118 bad:
2119         m_freem(m);
2120         return;
2121 }
2122
2123 static void
2124 icmp6_fasttimo_dispatch(netmsg_t nmsg)
2125 {
2126
2127         ASSERT_NETISR0;
2128
2129         /* Reply ASAP. */
2130         crit_enter();
2131         netisr_replymsg(&nmsg->base, 0);
2132         crit_exit();
2133
2134         mld6_fasttimeo();
2135
2136         callout_reset(&icmp6_fasttimo_ch, ICMP6_FASTTIMO, icmp6_fasttimo, NULL);
2137 }
2138
2139 static void
2140 icmp6_fasttimo(void *dummy __unused)
2141 {
2142         struct netmsg_base *nmsg = &icmp6_fasttimo_nmsg;
2143
2144         KKASSERT(mycpuid == 0);
2145
2146         crit_enter();
2147         if (nmsg->lmsg.ms_flags & MSGF_DONE)
2148                 netisr_sendmsg_oncpu(nmsg);
2149         crit_exit();
2150 }
2151
2152 static const char *
2153 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6,
2154                     struct in6_addr *tgt6)
2155 {
2156         static char buf[1024];
2157         ksnprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
2158                 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
2159         return buf;
2160 }
2161
2162 void
2163 icmp6_redirect_input(struct mbuf *m, int off)
2164 {
2165         struct ifnet *ifp = m->m_pkthdr.rcvif;
2166         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2167         struct nd_redirect *nd_rd;
2168         int icmp6len = ntohs(ip6->ip6_plen);
2169         char *lladdr = NULL;
2170         int lladdrlen = 0;
2171 #if 0
2172         u_char *redirhdr = NULL;
2173         int redirhdrlen = 0;
2174 #endif
2175         struct rtentry *rt = NULL;
2176         int is_router;
2177         int is_onlink;
2178         struct in6_addr src6 = ip6->ip6_src;
2179         struct in6_addr redtgt6;
2180         struct in6_addr reddst6;
2181         union nd_opts ndopts;
2182
2183         if (!m || !ifp)
2184                 return;
2185
2186         /* XXX if we are router, we don't update route by icmp6 redirect */
2187         if (ip6_forwarding)
2188                 goto freeit;
2189         if (!icmp6_rediraccept)
2190                 goto freeit;
2191
2192 #ifndef PULLDOWN_TEST
2193         IP6_EXTHDR_CHECK(m, off, icmp6len,);
2194         nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2195 #else
2196         IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2197         if (nd_rd == NULL) {
2198                 icmp6stat.icp6s_tooshort++;
2199                 return;
2200         }
2201 #endif
2202         redtgt6 = nd_rd->nd_rd_target;
2203         reddst6 = nd_rd->nd_rd_dst;
2204
2205         if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2206                 redtgt6.s6_addr16[1] = htons(ifp->if_index);
2207         if (IN6_IS_ADDR_LINKLOCAL(&reddst6))
2208                 reddst6.s6_addr16[1] = htons(ifp->if_index);
2209
2210         /* validation */
2211         if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2212                 nd6log((LOG_ERR,
2213                         "ICMP6 redirect sent from %s rejected; "
2214                         "must be from linklocal\n", ip6_sprintf(&src6)));
2215                 goto bad;
2216         }
2217         if (ip6->ip6_hlim != 255) {
2218                 nd6log((LOG_ERR,
2219                         "ICMP6 redirect sent from %s rejected; "
2220                         "hlim=%d (must be 255)\n",
2221                         ip6_sprintf(&src6), ip6->ip6_hlim));
2222                 goto bad;
2223         }
2224     {
2225         /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2226         struct sockaddr_in6 sin6;
2227         struct in6_addr *gw6;
2228
2229         bzero(&sin6, sizeof(sin6));
2230         sin6.sin6_family = AF_INET6;
2231         sin6.sin6_len = sizeof(struct sockaddr_in6);
2232         bcopy(&reddst6, &sin6.sin6_addr, sizeof reddst6);
2233         rt = rtpurelookup((struct sockaddr *)&sin6);
2234         if (rt != NULL) {
2235                 if (rt->rt_gateway == NULL ||
2236                     rt->rt_gateway->sa_family != AF_INET6) {
2237                         nd6log((LOG_ERR,
2238                             "ICMP6 redirect rejected; no route "
2239                             "with inet6 gateway found for redirect dst: %s\n",
2240                             icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2241                         --rt->rt_refcnt;
2242                         goto bad;
2243                 }
2244
2245                 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2246                 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2247                         nd6log((LOG_ERR,
2248                                 "ICMP6 redirect rejected; "
2249                                 "not equal to gw-for-src=%s (must be same): "
2250                                 "%s\n",
2251                                 ip6_sprintf(gw6),
2252                                 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2253                         --rt->rt_refcnt;
2254                         goto bad;
2255                 }
2256         } else {
2257                 nd6log((LOG_ERR,
2258                         "ICMP6 redirect rejected; "
2259                         "no route found for redirect dst: %s\n",
2260                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2261                 goto bad;
2262         }
2263         --rt->rt_refcnt;
2264         rt = NULL;
2265     }
2266         if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2267                 nd6log((LOG_ERR,
2268                         "ICMP6 redirect rejected; "
2269                         "redirect dst must be unicast: %s\n",
2270                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2271                 goto bad;
2272         }
2273
2274         is_router = is_onlink = 0;
2275         if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2276                 is_router = 1;  /* router case */
2277         if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2278                 is_onlink = 1;  /* on-link destination case */
2279         if (!is_router && !is_onlink) {
2280                 nd6log((LOG_ERR,
2281                         "ICMP6 redirect rejected; "
2282                         "neither router case nor onlink case: %s\n",
2283                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2284                 goto bad;
2285         }
2286         /* validation passed */
2287
2288         icmp6len -= sizeof(*nd_rd);
2289         nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2290         if (nd6_options(&ndopts) < 0) {
2291                 nd6log((LOG_INFO, "icmp6_redirect_input: "
2292                         "invalid ND option, rejected: %s\n",
2293                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2294                 /* nd6_options have incremented stats */
2295                 goto freeit;
2296         }
2297
2298         if (ndopts.nd_opts_tgt_lladdr) {
2299                 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2300                 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2301         }
2302
2303 #if 0
2304         if (ndopts.nd_opts_rh) {
2305                 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
2306                 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
2307         }
2308 #endif
2309
2310         if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2311                 nd6log((LOG_INFO,
2312                         "icmp6_redirect_input: lladdrlen mismatch for %s "
2313                         "(if %d, icmp6 packet %d): %s\n",
2314                         ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
2315                         icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2316                 goto bad;
2317         }
2318
2319         /* RFC 2461 8.3 */
2320         nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2321                          is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2322
2323         if (!is_onlink) {       /* better router case.  perform rtredirect. */
2324                 /* perform rtredirect */
2325                 struct sockaddr_in6 sdst;
2326                 struct sockaddr_in6 sgw;
2327                 struct sockaddr_in6 ssrc;
2328
2329                 bzero(&sdst, sizeof(sdst));
2330                 bzero(&sgw, sizeof(sgw));
2331                 bzero(&ssrc, sizeof(ssrc));
2332                 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2333                 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2334                         sizeof(struct sockaddr_in6);
2335                 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2336                 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2337                 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2338                 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
2339                            NULL, RTF_GATEWAY | RTF_HOST,
2340                            (struct sockaddr *)&ssrc);
2341         }
2342         /* finally update cached route in each socket via kpfctlinput */
2343     {
2344         struct sockaddr_in6 sdst;
2345
2346         bzero(&sdst, sizeof(sdst));
2347         sdst.sin6_family = AF_INET6;
2348         sdst.sin6_len = sizeof(struct sockaddr_in6);
2349         bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2350         kpfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2351 #ifdef IPSEC
2352         key_sa_routechange((struct sockaddr *)&sdst);
2353 #endif
2354     }
2355
2356 freeit:
2357         m_freem(m);
2358         return;
2359
2360 bad:
2361         icmp6stat.icp6s_badredirect++;
2362         m_freem(m);
2363 }
2364
2365 void
2366 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt)
2367 {
2368         struct ifnet *ifp;      /* my outgoing interface */
2369         struct in6_addr *ifp_ll6;
2370         struct in6_addr *router_ll6;
2371         struct ip6_hdr *sip6;   /* m0 as struct ip6_hdr */
2372         struct mbuf *m = NULL;  /* newly allocated one */
2373         struct ip6_hdr *ip6;    /* m as struct ip6_hdr */
2374         struct nd_redirect *nd_rd;
2375         size_t maxlen;
2376         u_char *p;
2377         struct ifnet *outif = NULL;
2378         struct sockaddr_in6 src_sa;
2379
2380         icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0);
2381
2382         /* if we are not router, we don't send icmp6 redirect */
2383         if (!ip6_forwarding || ip6_accept_rtadv)
2384                 goto fail;
2385
2386         /* sanity check */
2387         if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
2388                 goto fail;
2389
2390         /*
2391          * Address check:
2392          *  the source address must identify a neighbor, and
2393          *  the destination address must not be a multicast address
2394          *  [RFC 2461, sec 8.2]
2395          */
2396         sip6 = mtod(m0, struct ip6_hdr *);
2397         bzero(&src_sa, sizeof(src_sa));
2398         src_sa.sin6_family = AF_INET6;
2399         src_sa.sin6_len = sizeof(src_sa);
2400         src_sa.sin6_addr = sip6->ip6_src;
2401         /* we don't currently use sin6_scope_id, but eventually use it */
2402         if (in6_addr2zoneid(ifp, &sip6->ip6_src, &src_sa.sin6_scope_id))
2403                 goto fail;
2404         if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2405                 goto fail;
2406         if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2407                 goto fail;      /* what should we do here? */
2408
2409         /* rate limit */
2410         if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2411                 goto fail;
2412
2413         /*
2414          * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2415          * we almost always ask for an mbuf cluster for simplicity.
2416          * (MHLEN < IPV6_MMTU is almost always true)
2417          */
2418 #if IPV6_MMTU >= MCLBYTES
2419 # error assumption failed about IPV6_MMTU and MCLBYTES
2420 #endif
2421         m = m_getb(IPV6_MMTU, M_NOWAIT, MT_HEADER, M_PKTHDR);
2422         if (!m)
2423                 goto fail;
2424         m->m_len = 0;
2425         maxlen = M_TRAILINGSPACE(m);
2426         maxlen = min(IPV6_MMTU, maxlen);
2427         /* just for safety */
2428         if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2429             ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2430                 goto fail;
2431         }
2432
2433         {
2434                 /* get ip6 linklocal address for ifp(my outgoing interface). */
2435                 struct in6_ifaddr *ia;
2436                 if ((ia = in6ifa_ifpforlinklocal(ifp,
2437                                                  IN6_IFF_NOTREADY|
2438                                                  IN6_IFF_ANYCAST)) == NULL)
2439                         goto fail;
2440                 ifp_ll6 = &ia->ia_addr.sin6_addr;
2441         }
2442
2443         /* get ip6 linklocal address for the router. */
2444         if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2445                 struct sockaddr_in6 *sin6;
2446                 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2447                 router_ll6 = &sin6->sin6_addr;
2448                 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2449                         router_ll6 = NULL;
2450         } else
2451                 router_ll6 = NULL;
2452
2453         /* ip6 */
2454         ip6 = mtod(m, struct ip6_hdr *);
2455         ip6->ip6_flow = 0;
2456         ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2457         ip6->ip6_vfc |= IPV6_VERSION;
2458         /* ip6->ip6_plen will be set later */
2459         ip6->ip6_nxt = IPPROTO_ICMPV6;
2460         ip6->ip6_hlim = 255;
2461         /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2462         bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2463         bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2464
2465         /* ND Redirect */
2466         nd_rd = (struct nd_redirect *)(ip6 + 1);
2467         nd_rd->nd_rd_type = ND_REDIRECT;
2468         nd_rd->nd_rd_code = 0;
2469         nd_rd->nd_rd_reserved = 0;
2470         if (rt->rt_flags & RTF_GATEWAY) {
2471                 /*
2472                  * nd_rd->nd_rd_target must be a link-local address in
2473                  * better router cases.
2474                  */
2475                 if (!router_ll6)
2476                         goto fail;
2477                 bcopy(router_ll6, &nd_rd->nd_rd_target,
2478                       sizeof(nd_rd->nd_rd_target));
2479                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2480                       sizeof(nd_rd->nd_rd_dst));
2481         } else {
2482                 /* make sure redtgt == reddst */
2483                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2484                       sizeof(nd_rd->nd_rd_target));
2485                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2486                       sizeof(nd_rd->nd_rd_dst));
2487         }
2488
2489         p = (u_char *)(nd_rd + 1);
2490
2491         if (!router_ll6)
2492                 goto nolladdropt;
2493
2494         {
2495                 /* target lladdr option */
2496                 struct rtentry *rt_router = NULL;
2497                 int len;
2498                 struct sockaddr_dl *sdl;
2499                 struct nd_opt_hdr *nd_opt;
2500                 char *lladdr;
2501
2502                 rt_router = nd6_lookup(router_ll6, 0, ifp);
2503                 if (!rt_router)
2504                         goto nolladdropt;
2505                 len = sizeof(*nd_opt) + ifp->if_addrlen;
2506                 len = (len + 7) & ~7;   /* round by 8 */
2507                 /* safety check */
2508                 if (len + (p - (u_char *)ip6) > maxlen)
2509                         goto nolladdropt;
2510                 if (!(rt_router->rt_flags & RTF_GATEWAY) &&
2511                     (rt_router->rt_flags & RTF_LLINFO) &&
2512                     (rt_router->rt_gateway->sa_family == AF_LINK) &&
2513                     (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
2514                     sdl->sdl_alen) {
2515                         nd_opt = (struct nd_opt_hdr *)p;
2516                         nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2517                         nd_opt->nd_opt_len = len >> 3;
2518                         lladdr = (char *)(nd_opt + 1);
2519                         bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
2520                         p += len;
2521                 }
2522         }
2523 nolladdropt:;
2524
2525         m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2526
2527         /* just to be safe */
2528 #ifdef M_DECRYPTED      /*not openbsd*/
2529         if (m0->m_flags & M_DECRYPTED)
2530                 goto noredhdropt;
2531 #endif
2532         if (p - (u_char *)ip6 > maxlen)
2533                 goto noredhdropt;
2534
2535     {
2536         /* redirected header option */
2537         int len;
2538         struct nd_opt_rd_hdr *nd_opt_rh;
2539
2540         /*
2541          * compute the maximum size for icmp6 redirect header option.
2542          * XXX room for auth header?
2543          */
2544         len = maxlen - (p - (u_char *)ip6);
2545         len &= ~7;
2546
2547         /* This is just for simplicity. */
2548         if (m0->m_pkthdr.len != m0->m_len) {
2549                 if (m0->m_next) {
2550                         m_freem(m0->m_next);
2551                         m0->m_next = NULL;
2552                 }
2553                 m0->m_pkthdr.len = m0->m_len;
2554         }
2555
2556         /*
2557          * Redirected header option spec (RFC2461 4.6.3) talks nothing
2558          * about padding/truncate rule for the original IP packet.
2559          * From the discussion on IPv6imp in Feb 1999, the consensus was:
2560          * - "attach as much as possible" is the goal
2561          * - pad if not aligned (original size can be guessed by original
2562          *   ip6 header)
2563          * Following code adds the padding if it is simple enough,
2564          * and truncates if not.
2565          */
2566         if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2567                 panic("assumption failed in %s:%d", __FILE__, __LINE__);
2568
2569         if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2570                 /* not enough room, truncate */
2571                 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
2572         } else {
2573                 /* enough room, pad or truncate */
2574                 size_t extra;
2575
2576                 extra = m0->m_pkthdr.len % 8;
2577                 if (extra) {
2578                         /* pad if easy enough, truncate if not */
2579                         if (8 - extra <= M_TRAILINGSPACE(m0)) {
2580                                 /* pad */
2581                                 m0->m_len += (8 - extra);
2582                                 m0->m_pkthdr.len += (8 - extra);
2583                         } else {
2584                                 /* truncate */
2585                                 m0->m_pkthdr.len -= extra;
2586                                 m0->m_len -= extra;
2587                         }
2588                 }
2589                 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2590                 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
2591         }
2592
2593         nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2594         bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2595         nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2596         nd_opt_rh->nd_opt_rh_len = len >> 3;
2597         p += sizeof(*nd_opt_rh);
2598         m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2599
2600         /* connect m0 to m */
2601         m->m_next = m0;
2602         m->m_pkthdr.len = m->m_len + m0->m_len;
2603         m0 = NULL;
2604     }
2605 noredhdropt:;
2606         if (m0 != NULL) {
2607                 m_freem(m0);
2608                 m0 = NULL;
2609         }
2610
2611         /* XXX: clear embedded link IDs in the inner header */
2612         in6_clearscope(&sip6->ip6_src);
2613         in6_clearscope(&sip6->ip6_dst);
2614         in6_clearscope(&nd_rd->nd_rd_target);
2615         in6_clearscope(&nd_rd->nd_rd_dst);
2616
2617         ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2618
2619         nd_rd->nd_rd_cksum = 0;
2620         nd_rd->nd_rd_cksum
2621                 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen));
2622
2623         /* send the packet to outside... */
2624         ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2625         if (outif) {
2626                 icmp6_ifstat_inc(outif, ifs6_out_msg);
2627                 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2628         }
2629         icmp6stat.icp6s_outhist[ND_REDIRECT]++;
2630
2631         return;
2632
2633 fail:
2634         if (m)
2635                 m_freem(m);
2636         if (m0)
2637                 m_freem(m0);
2638 }
2639
2640 #ifdef HAVE_NRL_INPCB
2641 #define in6pcb          inpcb
2642 #define in6p_icmp6filt  inp_icmp6filt
2643 #endif
2644 /*
2645  * ICMPv6 socket option processing.
2646  */
2647 void
2648 icmp6_ctloutput(netmsg_t msg)
2649 {
2650         struct socket *so = msg->ctloutput.base.nm_so;
2651         struct sockopt *sopt = msg->ctloutput.nm_sopt;
2652         int error = 0;
2653         int optlen;
2654         struct inpcb *inp = so->so_pcb;
2655         int level, op, optname;
2656
2657         if (sopt) {
2658                 level = sopt->sopt_level;
2659                 op = sopt->sopt_dir;
2660                 optname = sopt->sopt_name;
2661                 optlen = sopt->sopt_valsize;
2662         } else
2663                 level = op = optname = optlen = 0;
2664
2665         if (level != IPPROTO_ICMPV6) {
2666                 error = EINVAL;
2667                 goto out;
2668         }
2669
2670         switch (op) {
2671         case PRCO_SETOPT:
2672                 switch (optname) {
2673                 case ICMP6_FILTER:
2674                     {
2675                         if (optlen != sizeof(struct icmp6_filter)) {
2676                                 error = EMSGSIZE;
2677                                 break;
2678                         }
2679                         if (inp->in6p_icmp6filt == NULL) {
2680                                 error = EINVAL;
2681                                 break;
2682                         }
2683                         error = soopt_to_kbuf(sopt, inp->in6p_icmp6filt, optlen,
2684                                 optlen);
2685                         break;
2686                     }
2687
2688                 default:
2689                         error = ENOPROTOOPT;
2690                         break;
2691                 }
2692                 break;
2693
2694         case PRCO_GETOPT:
2695                 switch (optname) {
2696                 case ICMP6_FILTER:
2697                     {
2698                         if (inp->in6p_icmp6filt == NULL) {
2699                                 error = EINVAL;
2700                                 break;
2701                         }
2702                         soopt_from_kbuf(sopt, inp->in6p_icmp6filt,
2703                                 sizeof(struct icmp6_filter));
2704                         break;
2705                     }
2706
2707                 default:
2708                         error = ENOPROTOOPT;
2709                         break;
2710                 }
2711                 break;
2712         }
2713 out:
2714         lwkt_replymsg(&msg->ctloutput.base.lmsg, error);
2715 }
2716 #ifdef HAVE_NRL_INPCB
2717 #undef in6pcb
2718 #undef in6p_icmp6filt
2719 #endif
2720
2721 #ifndef HAVE_PPSRATECHECK
2722 #ifndef timersub
2723 #define timersub(tvp, uvp, vvp)                                         \
2724         do {                                                            \
2725                 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec;          \
2726                 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec;       \
2727                 if ((vvp)->tv_usec < 0) {                               \
2728                         (vvp)->tv_sec--;                                \
2729                         (vvp)->tv_usec += 1000000;                      \
2730                 }                                                       \
2731         } while (0)
2732 #endif
2733
2734 /*
2735  * ppsratecheck(): packets (or events) per second limitation.
2736  */
2737 static int
2738 ppsratecheck(struct timeval *lasttime, int *curpps,
2739              int maxpps)        /* maximum pps allowed */
2740 {
2741         struct timeval tv, delta;
2742         int rv;
2743
2744         microtime(&tv);
2745
2746         timersub(&tv, lasttime, &delta);
2747
2748         /*
2749          * Check for 0,0 so that the message will be seen at least once.
2750          * If more than one second has passed since the last update of
2751          * lasttime, reset the counter.
2752          *
2753          * We do increment *curpps even in *curpps < maxpps case, as some may
2754          * try to use *curpps for stat purposes as well.
2755          */
2756         if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) ||
2757             delta.tv_sec >= 1) {
2758                 *lasttime = tv;
2759                 *curpps = 0;
2760                 rv = 1;
2761         } else if (maxpps < 0)
2762                 rv = 1;
2763         else if (*curpps < maxpps)
2764                 rv = 1;
2765         else
2766                 rv = 0;
2767
2768 #if 1 /* DIAGNOSTIC? */
2769         /* be careful about wrap-around */
2770         if (*curpps + 1 > *curpps)
2771                 *curpps = *curpps + 1;
2772 #else
2773         /*
2774          * assume that there's not too many calls to this function.
2775          * not sure if the assumption holds, as it depends on *caller's*
2776          * behavior, not the behavior of this function.
2777          * IMHO it is wrong to make assumption on the caller's behavior,
2778          * so the above #if is #if 1, not #ifdef DIAGNOSTIC.
2779          */
2780         *curpps = *curpps + 1;
2781 #endif
2782
2783         return (rv);
2784 }
2785 #endif
2786
2787 /*
2788  * Perform rate limit check.
2789  * Returns 0 if it is okay to send the icmp6 packet.
2790  * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2791  * limitation.
2792  *
2793  * XXX per-destination/type check necessary?
2794  */
2795 static int
2796 icmp6_ratelimit(const struct in6_addr *dst,     /* not used at this moment */
2797                 const int type,                 /* not used at this moment */
2798                 const int code)                 /* not used at this moment */
2799 {
2800         int ret;
2801
2802         ret = 0;        /* okay to send */
2803
2804         /* PPS limit */
2805         if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count,
2806             icmp6errppslim)) {
2807                 /* The packet is subject to rate limit */
2808                 ret++;
2809         }
2810
2811         return ret;
2812 }