sys/netinet6/ip6_output.c

   1 /*      $FreeBSD$       */
   2 /*      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei 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, 1990, 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  * 4. 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_output.c 8.3 (Berkeley) 1/21/94
  62  */
  63
  64 #include "opt_ip6fw.h"
  65 #include "opt_inet.h"
  66 #include "opt_inet6.h"
  67 #include "opt_ipsec.h"
  68
  69 #include <sys/param.h>
  70 #include <sys/malloc.h>
  71 #include <sys/mbuf.h>
  72 #include <sys/proc.h>
  73 #include <sys/errno.h>
  74 #include <sys/protosw.h>
  75 #include <sys/socket.h>
  76 #include <sys/socketvar.h>
  77 #include <sys/systm.h>
  78 #include <sys/kernel.h>
  79
  80 #include <net/if.h>
  81 #include <net/route.h>
  82 #include <net/pfil.h>
  83
  84 #include <netinet/in.h>
  85 #include <netinet/in_var.h>
  86 #include <netinet6/in6_var.h>
  87 #include <netinet/ip6.h>
  88 #include <netinet/icmp6.h>
  89 #include <netinet6/ip6_var.h>
  90 #include <netinet/in_pcb.h>
  91 #include <netinet/tcp_var.h>
  92 #include <netinet6/nd6.h>
  93
  94 #ifdef IPSEC
  95 #include <netinet6/ipsec.h>
  96 #ifdef INET6
  97 #include <netinet6/ipsec6.h>
  98 #endif
  99 #include <netkey/key.h>
 100 #endif /* IPSEC */
 101
 102 #ifdef FAST_IPSEC
 103 #include <netipsec/ipsec.h>
 104 #include <netipsec/ipsec6.h>
 105 #include <netipsec/key.h>
 106 #endif /* FAST_IPSEC */
 107
 108 #include <netinet6/ip6_fw.h>
 109
 110 #include <net/net_osdep.h>
 111
 112 #include <netinet6/ip6protosw.h>
 113
 114 static MALLOC_DEFINE(M_IPMOPTS, "ip6_moptions", "internet multicast options");
 115
 116 struct ip6_exthdrs {
 117         struct mbuf *ip6e_ip6;
 118         struct mbuf *ip6e_hbh;
 119         struct mbuf *ip6e_dest1;
 120         struct mbuf *ip6e_rthdr;
 121         struct mbuf *ip6e_dest2;
 122 };
 123
 124 static int ip6_pcbopt __P((int, u_char *, int, struct ip6_pktopts **,
 125                            int, int));
 126 static int ip6_pcbopts __P((struct ip6_pktopts **, struct mbuf *,
 127         struct socket *, struct sockopt *));
 128 static int ip6_getpcbopt __P((struct ip6_pktopts *, int, struct sockopt *));
 129 static int ip6_setpktoption __P((int, u_char *, int, struct ip6_pktopts *, int,
 130         int, int, int));
 131
 132 static int ip6_setmoptions __P((int, struct ip6_moptions **, struct mbuf *));
 133 static int ip6_getmoptions __P((int, struct ip6_moptions *, struct mbuf **));
 134 static int ip6_copyexthdr __P((struct mbuf **, caddr_t, int));
 135 static int ip6_insertfraghdr __P((struct mbuf *, struct mbuf *, int,
 136         struct ip6_frag **));
 137 static int ip6_insert_jumboopt __P((struct ip6_exthdrs *, u_int32_t));
 138 static int ip6_splithdr __P((struct mbuf *, struct ip6_exthdrs *));
 139 static int ip6_getpmtu __P((struct route_in6 *, struct route_in6 *,
 140         struct ifnet *, struct in6_addr *, u_long *, int *));
 141
 142
 143 /*
 144  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 145  * header (with pri, len, nxt, hlim, src, dst).
 146  * This function may modify ver and hlim only.
 147  * The mbuf chain containing the packet will be freed.
 148  * The mbuf opt, if present, will not be freed.
 149  *
 150  * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and
 151  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 152  * which is rt_rmx.rmx_mtu.
 153  */
 154 int
 155 ip6_output(m0, opt, ro, flags, im6o, ifpp, inp)
 156         struct mbuf *m0;
 157         struct ip6_pktopts *opt;
 158         struct route_in6 *ro;
 159         int flags;
 160         struct ip6_moptions *im6o;
 161         struct ifnet **ifpp;            /* XXX: just for statistics */
 162         struct inpcb *inp;
 163 {
 164         struct ip6_hdr *ip6, *mhip6;
 165         struct ifnet *ifp, *origifp;
 166         struct mbuf *m = m0;
 167         int hlen, tlen, len, off;
 168         struct route_in6 ip6route;
 169         struct sockaddr_in6 *dst;
 170         int error = 0;
 171         struct in6_ifaddr *ia = NULL;
 172         u_long mtu;
 173         int alwaysfrag, dontfrag;
 174         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 175         struct ip6_exthdrs exthdrs;
 176         struct in6_addr finaldst;
 177         struct route_in6 *ro_pmtu = NULL;
 178         int hdrsplit = 0;
 179         int needipsec = 0;
 180 #if defined(IPSEC) || defined(FAST_IPSEC)
 181         int needipsectun = 0;
 182         struct secpolicy *sp = NULL;
 183 #endif /*IPSEC || FAST_IPSEC*/
 184
 185         ip6 = mtod(m, struct ip6_hdr *);
 186         finaldst = ip6->ip6_dst;
 187
 188 #define MAKE_EXTHDR(hp, mp)                                             \
 189     do {                                                                \
 190         if (hp) {                                                       \
 191                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 192                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 193                     ((eh)->ip6e_len + 1) << 3);                         \
 194                 if (error)                                              \
 195                         goto freehdrs;                                  \
 196         }                                                               \
 197     } while (/*CONSTCOND*/ 0)
 198
 199         bzero(&exthdrs, sizeof(exthdrs));
 200
 201         if (opt) {
 202                 /* Hop-by-Hop options header */
 203                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 204                 /* Destination options header(1st part) */
 205                 if (opt->ip6po_rthdr) {
 206                         /*
 207                          * Destination options header(1st part)
 208                          * This only makes sence with a routing header.
 209                          * See Section 9.2 of RFC 3542.
 210                          * Disabling this part just for MIP6 convenience is
 211                          * a bad idea.  We need to think carefully about a
 212                          * way to make the advanced API coexist with MIP6
 213                          * options, which might automatically be inserted in
 214                          * the kernel.
 215                          */
 216                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 217                 }
 218                 /* Routing header */
 219                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 220                 /* Destination options header(2nd part) */
 221                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 222         }
 223
 224 #ifdef IPSEC
 225         /* get a security policy for this packet */
 226         if (inp == NULL)
 227                 sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
 228         else
 229                 sp = ipsec6_getpolicybypcb(m, IPSEC_DIR_OUTBOUND, inp, &error);
 230
 231         if (sp == NULL) {
 232                 ipsec6stat.out_inval++;
 233                 goto freehdrs;
 234         }
 235
 236         error = 0;
 237
 238         /* check policy */
 239         switch (sp->policy) {
 240         case IPSEC_POLICY_DISCARD:
 241                 /*
 242                  * This packet is just discarded.
 243                  */
 244                 ipsec6stat.out_polvio++;
 245                 goto freehdrs;
 246
 247         case IPSEC_POLICY_BYPASS:
 248         case IPSEC_POLICY_NONE:
 249                 /* no need to do IPsec. */
 250                 needipsec = 0;
 251                 break;
 252
 253         case IPSEC_POLICY_IPSEC:
 254                 if (sp->req == NULL) {
 255                         /* acquire a policy */
 256                         error = key_spdacquire(sp);
 257                         goto freehdrs;
 258                 }
 259                 needipsec = 1;
 260                 break;
 261
 262         case IPSEC_POLICY_ENTRUST:
 263         default:
 264                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
 265         }
 266 #endif /* IPSEC */
 267 #ifdef FAST_IPSEC
 268         /* get a security policy for this packet */
 269         if (inp == NULL)
 270                 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
 271         else
 272                 sp = ipsec_getpolicybysock(m, IPSEC_DIR_OUTBOUND, inp, &error);
 273
 274         if (sp == NULL) {
 275                 newipsecstat.ips_out_inval++;
 276                 goto freehdrs;
 277         }
 278
 279         error = 0;
 280
 281         /* check policy */
 282         switch (sp->policy) {
 283         case IPSEC_POLICY_DISCARD:
 284                 /*
 285                  * This packet is just discarded.
 286                  */
 287                 newipsecstat.ips_out_polvio++;
 288                 goto freehdrs;
 289
 290         case IPSEC_POLICY_BYPASS:
 291         case IPSEC_POLICY_NONE:
 292                 /* no need to do IPsec. */
 293                 needipsec = 0;
 294                 break;
 295
 296         case IPSEC_POLICY_IPSEC:
 297                 if (sp->req == NULL) {
 298                         /* acquire a policy */
 299                         error = key_spdacquire(sp);
 300                         goto freehdrs;
 301                 }
 302                 needipsec = 1;
 303                 break;
 304
 305         case IPSEC_POLICY_ENTRUST:
 306         default:
 307                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
 308         }
 309 #endif /* FAST_IPSEC */
 310
 311         /*
 312          * Calculate the total length of the extension header chain.
 313          * Keep the length of the unfragmentable part for fragmentation.
 314          */
 315         optlen = 0;
 316         if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len;
 317         if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len;
 318         if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len;
 319         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 320         /* NOTE: we don't add AH/ESP length here. do that later. */
 321         if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len;
 322
 323         /*
 324          * If we need IPsec, or there is at least one extension header,
 325          * separate IP6 header from the payload.
 326          */
 327         if ((needipsec || optlen) && !hdrsplit) {
 328                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 329                         m = NULL;
 330                         goto freehdrs;
 331                 }
 332                 m = exthdrs.ip6e_ip6;
 333                 hdrsplit++;
 334         }
 335
 336         /* adjust pointer */
 337         ip6 = mtod(m, struct ip6_hdr *);
 338
 339         /* adjust mbuf packet header length */
 340         m->m_pkthdr.len += optlen;
 341         plen = m->m_pkthdr.len - sizeof(*ip6);
 342
 343         /* If this is a jumbo payload, insert a jumbo payload option. */
 344         if (plen > IPV6_MAXPACKET) {
 345                 if (!hdrsplit) {
 346                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 347                                 m = NULL;
 348                                 goto freehdrs;
 349                         }
 350                         m = exthdrs.ip6e_ip6;
 351                         hdrsplit++;
 352                 }
 353                 /* adjust pointer */
 354                 ip6 = mtod(m, struct ip6_hdr *);
 355                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 356                         goto freehdrs;
 357                 ip6->ip6_plen = 0;
 358         } else
 359                 ip6->ip6_plen = htons(plen);
 360
 361         /*
 362          * Concatenate headers and fill in next header fields.
 363          * Here we have, on "m"
 364          *      IPv6 payload
 365          * and we insert headers accordingly.  Finally, we should be getting:
 366          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 367          *
 368          * during the header composing process, "m" points to IPv6 header.
 369          * "mprev" points to an extension header prior to esp.
 370          */
 371         {
 372                 u_char *nexthdrp = &ip6->ip6_nxt;
 373                 struct mbuf *mprev = m;
 374
 375                 /*
 376                  * we treat dest2 specially.  this makes IPsec processing
 377                  * much easier.  the goal here is to make mprev point the
 378                  * mbuf prior to dest2.
 379                  *
 380                  * result: IPv6 dest2 payload
 381                  * m and mprev will point to IPv6 header.
 382                  */
 383                 if (exthdrs.ip6e_dest2) {
 384                         if (!hdrsplit)
 385                                 panic("assumption failed: hdr not split");
 386                         exthdrs.ip6e_dest2->m_next = m->m_next;
 387                         m->m_next = exthdrs.ip6e_dest2;
 388                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 389                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 390                 }
 391
 392 #define MAKE_CHAIN(m, mp, p, i)\
 393     do {\
 394         if (m) {\
 395                 if (!hdrsplit) \
 396                         panic("assumption failed: hdr not split"); \
 397                 *mtod((m), u_char *) = *(p);\
 398                 *(p) = (i);\
 399                 p = mtod((m), u_char *);\
 400                 (m)->m_next = (mp)->m_next;\
 401                 (mp)->m_next = (m);\
 402                 (mp) = (m);\
 403         }\
 404     } while (/*CONSTCOND*/ 0)
 405                 /*
 406                  * result: IPv6 hbh dest1 rthdr dest2 payload
 407                  * m will point to IPv6 header.  mprev will point to the
 408                  * extension header prior to dest2 (rthdr in the above case).
 409                  */
 410                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 411                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 412                     IPPROTO_DSTOPTS);
 413                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 414                     IPPROTO_ROUTING);
 415
 416 #if defined(IPSEC) || defined(FAST_IPSEC)
 417                 if (!needipsec)
 418                         goto skip_ipsec2;
 419
 420                 /*
 421                  * pointers after IPsec headers are not valid any more.
 422                  * other pointers need a great care too.
 423                  * (IPsec routines should not mangle mbufs prior to AH/ESP)
 424                  */
 425                 exthdrs.ip6e_dest2 = NULL;
 426
 427             {
 428                 struct ip6_rthdr *rh = NULL;
 429                 int segleft_org = 0;
 430                 struct ipsec_output_state state;
 431
 432                 if (exthdrs.ip6e_rthdr) {
 433                         rh = mtod(exthdrs.ip6e_rthdr, struct ip6_rthdr *);
 434                         segleft_org = rh->ip6r_segleft;
 435                         rh->ip6r_segleft = 0;
 436                 }
 437
 438                 bzero(&state, sizeof(state));
 439                 state.m = m;
 440                 error = ipsec6_output_trans(&state, nexthdrp, mprev, sp, flags,
 441                     &needipsectun);
 442                 m = state.m;
 443                 if (error) {
 444                         /* mbuf is already reclaimed in ipsec6_output_trans. */
 445                         m = NULL;
 446                         switch (error) {
 447                         case EHOSTUNREACH:
 448                         case ENETUNREACH:
 449                         case EMSGSIZE:
 450                         case ENOBUFS:
 451                         case ENOMEM:
 452                                 break;
 453                         default:
 454                                 printf("ip6_output (ipsec): error code %d\n", error);
 455                                 /* FALLTHROUGH */
 456                         case ENOENT:
 457                                 /* don't show these error codes to the user */
 458                                 error = 0;
 459                                 break;
 460                         }
 461                         goto bad;
 462                 }
 463                 if (exthdrs.ip6e_rthdr) {
 464                         /* ah6_output doesn't modify mbuf chain */
 465                         rh->ip6r_segleft = segleft_org;
 466                 }
 467             }
 468 skip_ipsec2:;
 469 #endif
 470         }
 471
 472         /*
 473          * If there is a routing header, replace the destination address field
 474          * with the first hop of the routing header.
 475          */
 476         if (exthdrs.ip6e_rthdr) {
 477                 struct ip6_rthdr *rh =
 478                         (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr,
 479                                                   struct ip6_rthdr *));
 480                 struct ip6_rthdr0 *rh0;
 481                 struct in6_addr *addrs;
 482
 483                 switch (rh->ip6r_type) {
 484                 case IPV6_RTHDR_TYPE_0:
 485                          rh0 = (struct ip6_rthdr0 *)rh;
 486                          addrs = (struct in6_addr *)(rh0 + 1);
 487
 488                          ip6->ip6_dst = *addrs;
 489                          bcopy((caddr_t)(addrs + 1), (caddr_t)addrs,
 490                                sizeof(struct in6_addr)*(rh0->ip6r0_segleft - 1)
 491                                  );
 492                          *(addrs + rh0->ip6r0_segleft - 1) = finaldst;
 493                          break;
 494                 default:        /* is it possible? */
 495                          error = EINVAL;
 496                          goto bad;
 497                 }
 498         }
 499
 500         /* Source address validation */
 501         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 502             (flags & IPV6_DADOUTPUT) == 0) {
 503                 error = EOPNOTSUPP;
 504                 ip6stat.ip6s_badscope++;
 505                 goto bad;
 506         }
 507         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 508                 error = EOPNOTSUPP;
 509                 ip6stat.ip6s_badscope++;
 510                 goto bad;
 511         }
 512
 513         ip6stat.ip6s_localout++;
 514
 515         /*
 516          * Route packet.
 517          */
 518         if (ro == 0) {
 519                 ro = &ip6route;
 520                 bzero((caddr_t)ro, sizeof(*ro));
 521         }
 522         ro_pmtu = ro;
 523         if (opt && opt->ip6po_rthdr)
 524                 ro = &opt->ip6po_route;
 525         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 526
 527         /*
 528          * If there is a cached route,
 529          * check that it is to the same destination
 530          * and is still up. If not, free it and try again.
 531          */
 532         if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 533                          dst->sin6_family != AF_INET6 ||
 534                          !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_dst))) {
 535                 RTFREE(ro->ro_rt);
 536                 ro->ro_rt = (struct rtentry *)0;
 537         }
 538         if (ro->ro_rt == 0) {
 539                 bzero(dst, sizeof(*dst));
 540                 dst->sin6_family = AF_INET6;
 541                 dst->sin6_len = sizeof(struct sockaddr_in6);
 542                 dst->sin6_addr = ip6->ip6_dst;
 543         }
 544
 545         /*
 546          * if specified, try to fill in the traffic class field.
 547          * do not override if a non-zero value is already set.
 548          * we check the diffserv field and the ecn field separately.
 549          */
 550         if (opt && opt->ip6po_tclass >= 0) {
 551                 int mask = 0;
 552
 553                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 554                         mask |= 0xfc;
 555                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 556                         mask |= 0x03;
 557                 if (mask != 0)
 558                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 559         }
 560
 561         /* fill in or override the hop limit field, if necessary. */
 562         if (opt && opt->ip6po_hlim != -1)
 563                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 564         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 565                 if (im6o != NULL)
 566                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 567                 else
 568                         ip6->ip6_hlim = ip6_defmcasthlim;
 569         }
 570
 571 #if defined(IPSEC) || defined(FAST_IPSEC)
 572         if (needipsec && needipsectun) {
 573                 struct ipsec_output_state state;
 574
 575                 /*
 576                  * All the extension headers will become inaccessible
 577                  * (since they can be encrypted).
 578                  * Don't panic, we need no more updates to extension headers
 579                  * on inner IPv6 packet (since they are now encapsulated).
 580                  *
 581                  * IPv6 [ESP|AH] IPv6 [extension headers] payload
 582                  */
 583                 bzero(&exthdrs, sizeof(exthdrs));
 584                 exthdrs.ip6e_ip6 = m;
 585
 586                 bzero(&state, sizeof(state));
 587                 state.m = m;
 588                 state.ro = (struct route *)ro;
 589                 state.dst = (struct sockaddr *)dst;
 590
 591                 error = ipsec6_output_tunnel(&state, sp, flags);
 592
 593                 m = state.m;
 594                 ro = (struct route_in6 *)state.ro;
 595                 dst = (struct sockaddr_in6 *)state.dst;
 596                 if (error) {
 597                         /* mbuf is already reclaimed in ipsec6_output_tunnel. */
 598                         m0 = m = NULL;
 599                         m = NULL;
 600                         switch (error) {
 601                         case EHOSTUNREACH:
 602                         case ENETUNREACH:
 603                         case EMSGSIZE:
 604                         case ENOBUFS:
 605                         case ENOMEM:
 606                                 break;
 607                         default:
 608                                 printf("ip6_output (ipsec): error code %d\n", error);
 609                                 /* FALLTHROUGH */
 610                         case ENOENT:
 611                                 /* don't show these error codes to the user */
 612                                 error = 0;
 613                                 break;
 614                         }
 615                         goto bad;
 616                 }
 617
 618                 exthdrs.ip6e_ip6 = m;
 619         }
 620 #endif /* IPSEC */
 621
 622         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 623                 /* Unicast */
 624
 625 #define ifatoia6(ifa)   ((struct in6_ifaddr *)(ifa))
 626 #define sin6tosa(sin6)  ((struct sockaddr *)(sin6))
 627                 /* xxx
 628                  * interface selection comes here
 629                  * if an interface is specified from an upper layer,
 630                  * ifp must point it.
 631                  */
 632                 if (ro->ro_rt == 0) {
 633                         /*
 634                          * non-bsdi always clone routes, if parent is
 635                          * PRF_CLONING.
 636                          */
 637                         rtalloc((struct route *)ro);
 638                 }
 639                 if (ro->ro_rt == 0) {
 640                         ip6stat.ip6s_noroute++;
 641                         error = EHOSTUNREACH;
 642                         /* XXX in6_ifstat_inc(ifp, ifs6_out_discard); */
 643                         goto bad;
 644                 }
 645                 /* XXX rt not locked */
 646                 ia = ifatoia6(ro->ro_rt->rt_ifa);
 647                 ifp = ro->ro_rt->rt_ifp;
 648                 ro->ro_rt->rt_rmx.rmx_pksent++;
 649                 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
 650                         dst = (struct sockaddr_in6 *)ro->ro_rt->rt_gateway;
 651                 m->m_flags &= ~(M_BCAST | M_MCAST);     /* just in case */
 652
 653                 in6_ifstat_inc(ifp, ifs6_out_request);
 654
 655                 /*
 656                  * Check if the outgoing interface conflicts with
 657                  * the interface specified by ifi6_ifindex (if specified).
 658                  * Note that loopback interface is always okay.
 659                  * (this may happen when we are sending a packet to one of
 660                  *  our own addresses.)
 661                  */
 662                 if (opt && opt->ip6po_pktinfo
 663                  && opt->ip6po_pktinfo->ipi6_ifindex) {
 664                         if (!(ifp->if_flags & IFF_LOOPBACK)
 665                          && ifp->if_index != opt->ip6po_pktinfo->ipi6_ifindex) {
 666                                 ip6stat.ip6s_noroute++;
 667                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 668                                 error = EHOSTUNREACH;
 669                                 goto bad;
 670                         }
 671                 }
 672
 673                 if (opt && opt->ip6po_hlim != -1)
 674                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 675         } else {
 676                 /* Multicast */
 677                 struct  in6_multi *in6m;
 678
 679                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 680
 681                 /*
 682                  * See if the caller provided any multicast options
 683                  */
 684                 ifp = NULL;
 685                 if (im6o != NULL) {
 686                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 687                         if (im6o->im6o_multicast_ifp != NULL)
 688                                 ifp = im6o->im6o_multicast_ifp;
 689                 } else
 690                         ip6->ip6_hlim = ip6_defmcasthlim;
 691
 692                 /*
 693                  * See if the caller provided the outgoing interface
 694                  * as an ancillary data.
 695                  * Boundary check for ifindex is assumed to be already done.
 696                  */
 697                 if (opt && opt->ip6po_pktinfo && opt->ip6po_pktinfo->ipi6_ifindex)
 698                         ifp = ifnet_byindex(opt->ip6po_pktinfo->ipi6_ifindex);
 699
 700                 /*
 701                  * If the destination is a node-local scope multicast,
 702                  * the packet should be loop-backed only.
 703                  */
 704                 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 705                         /*
 706                          * If the outgoing interface is already specified,
 707                          * it should be a loopback interface.
 708                          */
 709                         if (ifp && (ifp->if_flags & IFF_LOOPBACK) == 0) {
 710                                 ip6stat.ip6s_badscope++;
 711                                 error = ENETUNREACH; /* XXX: better error? */
 712                                 /* XXX correct ifp? */
 713                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 714                                 goto bad;
 715                         } else {
 716                                 ifp = &loif[0];
 717                         }
 718                 }
 719
 720                 if (opt && opt->ip6po_hlim != -1)
 721                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 722
 723                 /*
 724                  * If caller did not provide an interface lookup a
 725                  * default in the routing table.  This is either a
 726                  * default for the speicfied group (i.e. a host
 727                  * route), or a multicast default (a route for the
 728                  * ``net'' ff00::/8).
 729                  */
 730                 if (ifp == NULL) {
 731                         if (ro->ro_rt == 0)
 732                                 ro->ro_rt = rtalloc1((struct sockaddr *)
 733                                                 &ro->ro_dst, 0, 0UL);
 734                         else
 735                                 RT_LOCK(ro->ro_rt);
 736                         if (ro->ro_rt == 0) {
 737                                 ip6stat.ip6s_noroute++;
 738                                 error = EHOSTUNREACH;
 739                                 /* XXX in6_ifstat_inc(ifp, ifs6_out_discard) */
 740                                 goto bad;
 741                         }
 742                         ia = ifatoia6(ro->ro_rt->rt_ifa);
 743                         ifp = ro->ro_rt->rt_ifp;
 744                         ro->ro_rt->rt_rmx.rmx_pksent++;
 745                         RT_UNLOCK(ro->ro_rt);
 746                 }
 747
 748                 if ((flags & IPV6_FORWARDING) == 0)
 749                         in6_ifstat_inc(ifp, ifs6_out_request);
 750                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 751
 752                 /*
 753                  * Confirm that the outgoing interface supports multicast.
 754                  */
 755                 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 756                         ip6stat.ip6s_noroute++;
 757                         in6_ifstat_inc(ifp, ifs6_out_discard);
 758                         error = ENETUNREACH;
 759                         goto bad;
 760                 }
 761                 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
 762                 if (in6m != NULL &&
 763                    (im6o == NULL || im6o->im6o_multicast_loop)) {
 764                         /*
 765                          * If we belong to the destination multicast group
 766                          * on the outgoing interface, and the caller did not
 767                          * forbid loopback, loop back a copy.
 768                          */
 769                         ip6_mloopback(ifp, m, dst);
 770                 } else {
 771                         /*
 772                          * If we are acting as a multicast router, perform
 773                          * multicast forwarding as if the packet had just
 774                          * arrived on the interface to which we are about
 775                          * to send.  The multicast forwarding function
 776                          * recursively calls this function, using the
 777                          * IPV6_FORWARDING flag to prevent infinite recursion.
 778                          *
 779                          * Multicasts that are looped back by ip6_mloopback(),
 780                          * above, will be forwarded by the ip6_input() routine,
 781                          * if necessary.
 782                          */
 783                         if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 784                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 785                                         m_freem(m);
 786                                         goto done;
 787                                 }
 788                         }
 789                 }
 790                 /*
 791                  * Multicasts with a hoplimit of zero may be looped back,
 792                  * above, but must not be transmitted on a network.
 793                  * Also, multicasts addressed to the loopback interface
 794                  * are not sent -- the above call to ip6_mloopback() will
 795                  * loop back a copy if this host actually belongs to the
 796                  * destination group on the loopback interface.
 797                  */
 798                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 799                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 800                         m_freem(m);
 801                         goto done;
 802                 }
 803         }
 804
 805         /*
 806          * Fill the outgoing inteface to tell the upper layer
 807          * to increment per-interface statistics.
 808          */
 809         if (ifpp)
 810                 *ifpp = ifp;
 811
 812         /* Determine path MTU. */
 813         if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu,
 814             &alwaysfrag)) != 0)
 815                 goto bad;
 816
 817         /*
 818          * The caller of this function may specify to use the minimum MTU
 819          * in some cases.
 820          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 821          * setting.  The logic is a bit complicated; by default, unicast
 822          * packets will follow path MTU while multicast packets will be sent at
 823          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 824          * including unicast ones will be sent at the minimum MTU.  Multicast
 825          * packets will always be sent at the minimum MTU unless
 826          * IP6PO_MINMTU_DISABLE is explicitly specified.
 827          * See RFC 3542 for more details.
 828          */
 829         if (mtu > IPV6_MMTU) {
 830                 if ((flags & IPV6_MINMTU))
 831                         mtu = IPV6_MMTU;
 832                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 833                         mtu = IPV6_MMTU;
 834                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 835                          (opt == NULL ||
 836                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 837                         mtu = IPV6_MMTU;
 838                 }
 839         }
 840
 841         /* Fake scoped addresses */
 842         if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
 843                 /*
 844                  * If source or destination address is a scoped address, and
 845                  * the packet is going to be sent to a loopback interface,
 846                  * we should keep the original interface.
 847                  */
 848
 849                 /*
 850                  * XXX: this is a very experimental and temporary solution.
 851                  * We eventually have sockaddr_in6 and use the sin6_scope_id
 852                  * field of the structure here.
 853                  * We rely on the consistency between two scope zone ids
 854                  * of source and destination, which should already be assured.
 855                  * Larger scopes than link will be supported in the future.
 856                  */
 857                 origifp = NULL;
 858                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
 859                         origifp = ifnet_byindex(ntohs(ip6->ip6_src.s6_addr16[1]));
 860                 else if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
 861                         origifp = ifnet_byindex(ntohs(ip6->ip6_dst.s6_addr16[1]));
 862                 /*
 863                  * XXX: origifp can be NULL even in those two cases above.
 864                  * For example, if we remove the (only) link-local address
 865                  * from the loopback interface, and try to send a link-local
 866                  * address without link-id information.  Then the source
 867                  * address is ::1, and the destination address is the
 868                  * link-local address with its s6_addr16[1] being zero.
 869                  * What is worse, if the packet goes to the loopback interface
 870                  * by a default rejected route, the null pointer would be
 871                  * passed to looutput, and the kernel would hang.
 872                  * The following last resort would prevent such disaster.
 873                  */
 874                 if (origifp == NULL)
 875                         origifp = ifp;
 876         }
 877         else
 878                 origifp = ifp;
 879         /*
 880          * clear embedded scope identifiers if necessary.
 881          * in6_clearscope will touch the addresses only when necessary.
 882          */
 883         in6_clearscope(&ip6->ip6_src);
 884         in6_clearscope(&ip6->ip6_dst);
 885
 886         /*
 887          * Check with the firewall...
 888          */
 889         if (ip6_fw_enable && ip6_fw_chk_ptr) {
 890                 u_short port = 0;
 891                 m->m_pkthdr.rcvif = NULL;       /* XXX */
 892                 /* If ipfw says divert, we have to just drop packet */
 893                 if ((*ip6_fw_chk_ptr)(&ip6, ifp, &port, &m)) {
 894                         m_freem(m);
 895                         goto done;
 896                 }
 897                 if (!m) {
 898                         error = EACCES;
 899                         goto done;
 900                 }
 901         }
 902
 903         /*
 904          * If the outgoing packet contains a hop-by-hop options header,
 905          * it must be examined and processed even by the source node.
 906          * (RFC 2460, section 4.)
 907          */
 908         if (exthdrs.ip6e_hbh) {
 909                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 910                 u_int32_t dummy1; /* XXX unused */
 911                 u_int32_t dummy2; /* XXX unused */
 912
 913 #ifdef DIAGNOSTIC
 914                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 915                         panic("ip6e_hbh is not continuous");
 916 #endif
 917                 /*
 918                  *  XXX: if we have to send an ICMPv6 error to the sender,
 919                  *       we need the M_LOOP flag since icmp6_error() expects
 920                  *       the IPv6 and the hop-by-hop options header are
 921                  *       continuous unless the flag is set.
 922                  */
 923                 m->m_flags |= M_LOOP;
 924                 m->m_pkthdr.rcvif = ifp;
 925                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 926                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 927                     &dummy1, &dummy2) < 0) {
 928                         /* m was already freed at this point */
 929                         error = EINVAL;/* better error? */
 930                         goto done;
 931                 }
 932                 m->m_flags &= ~M_LOOP; /* XXX */
 933                 m->m_pkthdr.rcvif = NULL;
 934         }
 935
 936         /* Jump over all PFIL processing if hooks are not active. */
 937         if (inet6_pfil_hook.ph_busy_count == -1)
 938                 goto passout;
 939
 940         /* Run through list of hooks for output packets. */
 941         error = pfil_run_hooks(&inet6_pfil_hook, &m, ifp, PFIL_OUT, inp);
 942         if (error != 0 || m == NULL)
 943                 goto done;
 944         ip6 = mtod(m, struct ip6_hdr *);
 945
 946 passout:
 947         /*
 948          * Send the packet to the outgoing interface.
 949          * If necessary, do IPv6 fragmentation before sending.
 950          *
 951          * the logic here is rather complex:
 952          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 953          * 1-a: send as is if tlen <= path mtu
 954          * 1-b: fragment if tlen > path mtu
 955          *
 956          * 2: if user asks us not to fragment (dontfrag == 1)
 957          * 2-a: send as is if tlen <= interface mtu
 958          * 2-b: error if tlen > interface mtu
 959          *
 960          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 961          *      always fragment
 962          *
 963          * 4: if dontfrag == 1 && alwaysfrag == 1
 964          *      error, as we cannot handle this conflicting request
 965          */
 966         tlen = m->m_pkthdr.len;
 967
 968         if (opt && (opt->ip6po_flags & IP6PO_DONTFRAG))
 969                 dontfrag = 1;
 970         else
 971                 dontfrag = 0;
 972         if (dontfrag && alwaysfrag) {   /* case 4 */
 973                 /* conflicting request - can't transmit */
 974                 error = EMSGSIZE;
 975                 goto bad;
 976         }
 977         if (dontfrag && tlen > IN6_LINKMTU(ifp)) {      /* case 2-b */
 978                 /*
 979                  * Even if the DONTFRAG option is specified, we cannot send the
 980                  * packet when the data length is larger than the MTU of the
 981                  * outgoing interface.
 982                  * Notify the error by sending IPV6_PATHMTU ancillary data as
 983                  * well as returning an error code (the latter is not described
 984                  * in the API spec.)
 985                  */
 986                 u_int32_t mtu32;
 987                 struct ip6ctlparam ip6cp;
 988
 989                 mtu32 = (u_int32_t)mtu;
 990                 bzero(&ip6cp, sizeof(ip6cp));
 991                 ip6cp.ip6c_cmdarg = (void *)&mtu32;
 992                 pfctlinput2(PRC_MSGSIZE, (struct sockaddr *)&ro_pmtu->ro_dst,
 993                     (void *)&ip6cp);
 994
 995                 error = EMSGSIZE;
 996                 goto bad;
 997         }
 998
 999         /*
1000          * transmit packet without fragmentation
1001          */
1002         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
1003                 struct in6_ifaddr *ia6;
1004
1005                 ip6 = mtod(m, struct ip6_hdr *);
1006                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1007                 if (ia6) {
1008                         /* Record statistics for this interface address. */
1009                         ia6->ia_ifa.if_opackets++;
1010                         ia6->ia_ifa.if_obytes += m->m_pkthdr.len;
1011                 }
1012 #ifdef IPSEC
1013                 /* clean ipsec history once it goes out of the node */
1014                 ipsec_delaux(m);
1015 #endif
1016                 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
1017                 goto done;
1018         }
1019
1020         /*
1021          * try to fragment the packet.  case 1-b and 3
1022          */
1023         if (mtu < IPV6_MMTU) {
1024                 /* path MTU cannot be less than IPV6_MMTU */
1025                 error = EMSGSIZE;
1026                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1027                 goto bad;
1028         } else if (ip6->ip6_plen == 0) {
1029                 /* jumbo payload cannot be fragmented */
1030                 error = EMSGSIZE;
1031                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1032                 goto bad;
1033         } else {
1034                 struct mbuf **mnext, *m_frgpart;
1035                 struct ip6_frag *ip6f;
1036                 u_int32_t id = htonl(ip6_randomid());
1037                 u_char nextproto;
1038 #if 0
1039                 struct ip6ctlparam ip6cp;
1040                 u_int32_t mtu32;
1041 #endif
1042                 int qslots = ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len;
1043
1044                 /*
1045                  * Too large for the destination or interface;
1046                  * fragment if possible.
1047                  * Must be able to put at least 8 bytes per fragment.
1048                  */
1049                 hlen = unfragpartlen;
1050                 if (mtu > IPV6_MAXPACKET)
1051                         mtu = IPV6_MAXPACKET;
1052
1053 #if 0
1054                 /*
1055                  * It is believed this code is a leftover from the
1056                  * development of the IPV6_RECVPATHMTU sockopt and
1057                  * associated work to implement RFC3542.
1058                  * It's not entirely clear what the intent of the API
1059                  * is at this point, so disable this code for now.
1060                  * The IPV6_RECVPATHMTU sockopt and/or IPV6_DONTFRAG
1061                  * will send notifications if the application requests.
1062                  */
1063
1064                 /* Notify a proper path MTU to applications. */
1065                 mtu32 = (u_int32_t)mtu;
1066                 bzero(&ip6cp, sizeof(ip6cp));
1067                 ip6cp.ip6c_cmdarg = (void *)&mtu32;
1068                 pfctlinput2(PRC_MSGSIZE, (struct sockaddr *)&ro_pmtu->ro_dst,
1069                     (void *)&ip6cp);
1070 #endif
1071
1072                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
1073                 if (len < 8) {
1074                         error = EMSGSIZE;
1075                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1076                         goto bad;
1077                 }
1078
1079                 /*
1080                  * Verify that we have any chance at all of being able to queue
1081                  *      the packet or packet fragments
1082                  */
1083                 if (qslots <= 0 || ((u_int)qslots * (mtu - hlen)
1084                     < tlen  /* - hlen */)) {
1085                         error = ENOBUFS;
1086                         ip6stat.ip6s_odropped++;
1087                         goto bad;
1088                 }
1089
1090                 mnext = &m->m_nextpkt;
1091
1092                 /*
1093                  * Change the next header field of the last header in the
1094                  * unfragmentable part.
1095                  */
1096                 if (exthdrs.ip6e_rthdr) {
1097                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1098                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1099                 } else if (exthdrs.ip6e_dest1) {
1100                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1101                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1102                 } else if (exthdrs.ip6e_hbh) {
1103                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1104                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1105                 } else {
1106                         nextproto = ip6->ip6_nxt;
1107                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1108                 }
1109
1110                 /*
1111                  * Loop through length of segment after first fragment,
1112                  * make new header and copy data of each part and link onto
1113                  * chain.
1114                  */
1115                 m0 = m;
1116                 for (off = hlen; off < tlen; off += len) {
1117                         MGETHDR(m, M_DONTWAIT, MT_HEADER);
1118                         if (!m) {
1119                                 error = ENOBUFS;
1120                                 ip6stat.ip6s_odropped++;
1121                                 goto sendorfree;
1122                         }
1123                         m->m_pkthdr.rcvif = NULL;
1124                         m->m_flags = m0->m_flags & M_COPYFLAGS;
1125                         *mnext = m;
1126                         mnext = &m->m_nextpkt;
1127                         m->m_data += max_linkhdr;
1128                         mhip6 = mtod(m, struct ip6_hdr *);
1129                         *mhip6 = *ip6;
1130                         m->m_len = sizeof(*mhip6);
1131                         error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
1132                         if (error) {
1133                                 ip6stat.ip6s_odropped++;
1134                                 goto sendorfree;
1135                         }
1136                         ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
1137                         if (off + len >= tlen)
1138                                 len = tlen - off;
1139                         else
1140                                 ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
1141                         mhip6->ip6_plen = htons((u_short)(len + hlen +
1142                             sizeof(*ip6f) - sizeof(struct ip6_hdr)));
1143                         if ((m_frgpart = m_copy(m0, off, len)) == 0) {
1144                                 error = ENOBUFS;
1145                                 ip6stat.ip6s_odropped++;
1146                                 goto sendorfree;
1147                         }
1148                         m_cat(m, m_frgpart);
1149                         m->m_pkthdr.len = len + hlen + sizeof(*ip6f);
1150                         m->m_pkthdr.rcvif = (struct ifnet *)0;
1151                         ip6f->ip6f_reserved = 0;
1152                         ip6f->ip6f_ident = id;
1153                         ip6f->ip6f_nxt = nextproto;
1154                         ip6stat.ip6s_ofragments++;
1155                         in6_ifstat_inc(ifp, ifs6_out_fragcreat);
1156                 }
1157
1158                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1159         }
1160
1161         /*
1162          * Remove leading garbages.
1163          */
1164 sendorfree:
1165         m = m0->m_nextpkt;
1166         m0->m_nextpkt = 0;
1167         m_freem(m0);
1168         for (m0 = m; m; m = m0) {
1169                 m0 = m->m_nextpkt;
1170                 m->m_nextpkt = 0;
1171                 if (error == 0) {
1172                         /* Record statistics for this interface address. */
1173                         if (ia) {
1174                                 ia->ia_ifa.if_opackets++;
1175                                 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1176                         }
1177 #ifdef IPSEC
1178                         /* clean ipsec history once it goes out of the node */
1179                         ipsec_delaux(m);
1180 #endif
1181                         error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
1182                 } else
1183                         m_freem(m);
1184         }
1185
1186         if (error == 0)
1187                 ip6stat.ip6s_fragmented++;
1188
1189 done:
1190         if (ro == &ip6route && ro->ro_rt) { /* brace necessary for RTFREE */
1191                 RTFREE(ro->ro_rt);
1192         } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) {
1193                 RTFREE(ro_pmtu->ro_rt);
1194         }
1195
1196 #ifdef IPSEC
1197         if (sp != NULL)
1198                 key_freesp(sp);
1199 #endif /* IPSEC */
1200 #ifdef FAST_IPSEC
1201         if (sp != NULL)
1202                 KEY_FREESP(&sp);
1203 #endif /* FAST_IPSEC */
1204
1205         return (error);
1206
1207 freehdrs:
1208         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1209         m_freem(exthdrs.ip6e_dest1);
1210         m_freem(exthdrs.ip6e_rthdr);
1211         m_freem(exthdrs.ip6e_dest2);
1212         /* FALLTHROUGH */
1213 bad:
1214         m_freem(m);
1215         goto done;
1216 }
1217
1218 static int
1219 ip6_copyexthdr(mp, hdr, hlen)
1220         struct mbuf **mp;
1221         caddr_t hdr;
1222         int hlen;
1223 {
1224         struct mbuf *m;
1225
1226         if (hlen > MCLBYTES)
1227                 return (ENOBUFS); /* XXX */
1228
1229         MGET(m, M_DONTWAIT, MT_DATA);
1230         if (!m)
1231                 return (ENOBUFS);
1232
1233         if (hlen > MLEN) {
1234                 MCLGET(m, M_DONTWAIT);
1235                 if ((m->m_flags & M_EXT) == 0) {
1236                         m_free(m);
1237                         return (ENOBUFS);
1238                 }
1239         }
1240         m->m_len = hlen;
1241         if (hdr)
1242                 bcopy(hdr, mtod(m, caddr_t), hlen);
1243
1244         *mp = m;
1245         return (0);
1246 }
1247
1248 /*
1249  * Insert jumbo payload option.
1250  */
1251 static int
1252 ip6_insert_jumboopt(exthdrs, plen)
1253         struct ip6_exthdrs *exthdrs;
1254         u_int32_t plen;
1255 {
1256         struct mbuf *mopt;
1257         u_char *optbuf;
1258         u_int32_t v;
1259
1260 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1261
1262         /*
1263          * If there is no hop-by-hop options header, allocate new one.
1264          * If there is one but it doesn't have enough space to store the
1265          * jumbo payload option, allocate a cluster to store the whole options.
1266          * Otherwise, use it to store the options.
1267          */
1268         if (exthdrs->ip6e_hbh == 0) {
1269                 MGET(mopt, M_DONTWAIT, MT_DATA);
1270                 if (mopt == 0)
1271                         return (ENOBUFS);
1272                 mopt->m_len = JUMBOOPTLEN;
1273                 optbuf = mtod(mopt, u_char *);
1274                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1275                 exthdrs->ip6e_hbh = mopt;
1276         } else {
1277                 struct ip6_hbh *hbh;
1278
1279                 mopt = exthdrs->ip6e_hbh;
1280                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1281                         /*
1282                          * XXX assumption:
1283                          * - exthdrs->ip6e_hbh is not referenced from places
1284                          *   other than exthdrs.
1285                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1286                          */
1287                         int oldoptlen = mopt->m_len;
1288                         struct mbuf *n;
1289
1290                         /*
1291                          * XXX: give up if the whole (new) hbh header does
1292                          * not fit even in an mbuf cluster.
1293                          */
1294                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1295                                 return (ENOBUFS);
1296
1297                         /*
1298                          * As a consequence, we must always prepare a cluster
1299                          * at this point.
1300                          */
1301                         MGET(n, M_DONTWAIT, MT_DATA);
1302                         if (n) {
1303                                 MCLGET(n, M_DONTWAIT);
1304                                 if ((n->m_flags & M_EXT) == 0) {
1305                                         m_freem(n);
1306                                         n = NULL;
1307                                 }
1308                         }
1309                         if (!n)
1310                                 return (ENOBUFS);
1311                         n->m_len = oldoptlen + JUMBOOPTLEN;
1312                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1313                             oldoptlen);
1314                         optbuf = mtod(n, caddr_t) + oldoptlen;
1315                         m_freem(mopt);
1316                         mopt = exthdrs->ip6e_hbh = n;
1317                 } else {
1318                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1319                         mopt->m_len += JUMBOOPTLEN;
1320                 }
1321                 optbuf[0] = IP6OPT_PADN;
1322                 optbuf[1] = 1;
1323
1324                 /*
1325                  * Adjust the header length according to the pad and
1326                  * the jumbo payload option.
1327                  */
1328                 hbh = mtod(mopt, struct ip6_hbh *);
1329                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1330         }
1331
1332         /* fill in the option. */
1333         optbuf[2] = IP6OPT_JUMBO;
1334         optbuf[3] = 4;
1335         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1336         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1337
1338         /* finally, adjust the packet header length */
1339         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1340
1341         return (0);
1342 #undef JUMBOOPTLEN
1343 }
1344
1345 /*
1346  * Insert fragment header and copy unfragmentable header portions.
1347  */
1348 static int
1349 ip6_insertfraghdr(m0, m, hlen, frghdrp)
1350         struct mbuf *m0, *m;
1351         int hlen;
1352         struct ip6_frag **frghdrp;
1353 {
1354         struct mbuf *n, *mlast;
1355
1356         if (hlen > sizeof(struct ip6_hdr)) {
1357                 n = m_copym(m0, sizeof(struct ip6_hdr),
1358                     hlen - sizeof(struct ip6_hdr), M_DONTWAIT);
1359                 if (n == 0)
1360                         return (ENOBUFS);
1361                 m->m_next = n;
1362         } else
1363                 n = m;
1364
1365         /* Search for the last mbuf of unfragmentable part. */
1366         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1367                 ;
1368
1369         if ((mlast->m_flags & M_EXT) == 0 &&
1370             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1371                 /* use the trailing space of the last mbuf for the fragment hdr */
1372                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1373                     mlast->m_len);
1374                 mlast->m_len += sizeof(struct ip6_frag);
1375                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1376         } else {
1377                 /* allocate a new mbuf for the fragment header */
1378                 struct mbuf *mfrg;
1379
1380                 MGET(mfrg, M_DONTWAIT, MT_DATA);
1381                 if (mfrg == 0)
1382                         return (ENOBUFS);
1383                 mfrg->m_len = sizeof(struct ip6_frag);
1384                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1385                 mlast->m_next = mfrg;
1386         }
1387
1388         return (0);
1389 }
1390
1391 static int
1392 ip6_getpmtu(ro_pmtu, ro, ifp, dst, mtup, alwaysfragp)
1393         struct route_in6 *ro_pmtu, *ro;
1394         struct ifnet *ifp;
1395         struct in6_addr *dst;
1396         u_long *mtup;
1397         int *alwaysfragp;
1398 {
1399         u_int32_t mtu = 0;
1400         int alwaysfrag = 0;
1401         int error = 0;
1402
1403         if (ro_pmtu != ro) {
1404                 /* The first hop and the final destination may differ. */
1405                 struct sockaddr_in6 *sa6_dst =
1406                     (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1407                 if (ro_pmtu->ro_rt &&
1408                     ((ro_pmtu->ro_rt->rt_flags & RTF_UP) == 0 ||
1409                      !IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))) {
1410                         RTFREE(ro_pmtu->ro_rt);
1411                         ro_pmtu->ro_rt = (struct rtentry *)NULL;
1412                 }
1413                 if (ro_pmtu->ro_rt == NULL) {
1414                         bzero(sa6_dst, sizeof(*sa6_dst));
1415                         sa6_dst->sin6_family = AF_INET6;
1416                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1417                         sa6_dst->sin6_addr = *dst;
1418
1419                         rtalloc((struct route *)ro_pmtu);
1420                 }
1421         }
1422         if (ro_pmtu->ro_rt) {
1423                 u_int32_t ifmtu;
1424                 struct in_conninfo inc;
1425
1426                 bzero(&inc, sizeof(inc));
1427                 inc.inc_flags = 1; /* IPv6 */
1428                 inc.inc6_faddr = *dst;
1429
1430                 if (ifp == NULL)
1431                         ifp = ro_pmtu->ro_rt->rt_ifp;
1432                 ifmtu = IN6_LINKMTU(ifp);
1433                 mtu = tcp_hc_getmtu(&inc);
1434                 if (mtu)
1435                         mtu = min(mtu, ro_pmtu->ro_rt->rt_rmx.rmx_mtu);
1436                 else
1437                         mtu = ro_pmtu->ro_rt->rt_rmx.rmx_mtu;
1438                 if (mtu == 0)
1439                         mtu = ifmtu;
1440                 else if (mtu < IPV6_MMTU) {
1441                         /*
1442                          * RFC2460 section 5, last paragraph:
1443                          * if we record ICMPv6 too big message with
1444                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1445                          * or smaller, with framgent header attached.
1446                          * (fragment header is needed regardless from the
1447                          * packet size, for translators to identify packets)
1448                          */
1449                         alwaysfrag = 1;
1450                         mtu = IPV6_MMTU;
1451                 } else if (mtu > ifmtu) {
1452                         /*
1453                          * The MTU on the route is larger than the MTU on
1454                          * the interface!  This shouldn't happen, unless the
1455                          * MTU of the interface has been changed after the
1456                          * interface was brought up.  Change the MTU in the
1457                          * route to match the interface MTU (as long as the
1458                          * field isn't locked).
1459                          */
1460                         mtu = ifmtu;
1461                         ro_pmtu->ro_rt->rt_rmx.rmx_mtu = mtu;
1462                 }
1463         } else if (ifp) {
1464                 mtu = IN6_LINKMTU(ifp);
1465         } else
1466                 error = EHOSTUNREACH; /* XXX */
1467
1468         *mtup = mtu;
1469         if (alwaysfragp)
1470                 *alwaysfragp = alwaysfrag;
1471         return (error);
1472 }
1473
1474 /*
1475  * IP6 socket option processing.
1476  */
1477 int
1478 ip6_ctloutput(so, sopt)
1479         struct socket *so;
1480         struct sockopt *sopt;
1481 {
1482         int privileged, optdatalen, uproto;
1483         void *optdata;
1484         struct inpcb *in6p = sotoinpcb(so);
1485         int error, optval;
1486         int level, op, optname;
1487         int optlen;
1488         struct thread *td;
1489
1490         if (sopt) {
1491                 level = sopt->sopt_level;
1492                 op = sopt->sopt_dir;
1493                 optname = sopt->sopt_name;
1494                 optlen = sopt->sopt_valsize;
1495                 td = sopt->sopt_td;
1496         } else {
1497                 panic("ip6_ctloutput: arg soopt is NULL");
1498         }
1499         error = optval = 0;
1500
1501         privileged = (td == 0 || suser(td)) ? 0 : 1;
1502         uproto = (int)so->so_proto->pr_protocol;
1503
1504         if (level == IPPROTO_IPV6) {
1505                 switch (op) {
1506
1507                 case SOPT_SET:
1508                         switch (optname) {
1509                         case IPV6_2292PKTOPTIONS:
1510 #ifdef IPV6_PKTOPTIONS
1511                         case IPV6_PKTOPTIONS:
1512 #endif
1513                         {
1514                                 struct mbuf *m;
1515
1516                                 error = soopt_getm(sopt, &m); /* XXX */
1517                                 if (error != 0)
1518                                         break;
1519                                 error = soopt_mcopyin(sopt, m); /* XXX */
1520                                 if (error != 0)
1521                                         break;
1522                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1523                                                     m, so, sopt);
1524                                 m_freem(m); /* XXX */
1525                                 break;
1526                         }
1527
1528                         /*
1529                          * Use of some Hop-by-Hop options or some
1530                          * Destination options, might require special
1531                          * privilege.  That is, normal applications
1532                          * (without special privilege) might be forbidden
1533                          * from setting certain options in outgoing packets,
1534                          * and might never see certain options in received
1535                          * packets. [RFC 2292 Section 6]
1536                          * KAME specific note:
1537                          *  KAME prevents non-privileged users from sending or
1538                          *  receiving ANY hbh/dst options in order to avoid
1539                          *  overhead of parsing options in the kernel.
1540                          */
1541                         case IPV6_RECVHOPOPTS:
1542                         case IPV6_RECVDSTOPTS:
1543                         case IPV6_RECVRTHDRDSTOPTS:
1544                                 if (!privileged) {
1545                                         error = EPERM;
1546                                         break;
1547                                 }
1548                                 /* FALLTHROUGH */
1549                         case IPV6_UNICAST_HOPS:
1550                         case IPV6_HOPLIMIT:
1551                         case IPV6_FAITH:
1552
1553                         case IPV6_RECVPKTINFO:
1554                         case IPV6_RECVHOPLIMIT:
1555                         case IPV6_RECVRTHDR:
1556                         case IPV6_RECVPATHMTU:
1557                         case IPV6_RECVTCLASS:
1558                         case IPV6_V6ONLY:
1559                         case IPV6_AUTOFLOWLABEL:
1560                                 if (optlen != sizeof(int)) {
1561                                         error = EINVAL;
1562                                         break;
1563                                 }
1564                                 error = sooptcopyin(sopt, &optval,
1565                                         sizeof optval, sizeof optval);
1566                                 if (error)
1567                                         break;
1568                                 switch (optname) {
1569
1570                                 case IPV6_UNICAST_HOPS:
1571                                         if (optval < -1 || optval >= 256)
1572                                                 error = EINVAL;
1573                                         else {
1574                                                 /* -1 = kernel default */
1575                                                 in6p->in6p_hops = optval;
1576                                                 if ((in6p->in6p_vflag &
1577                                                      INP_IPV4) != 0)
1578                                                         in6p->inp_ip_ttl = optval;
1579                                         }
1580                                         break;
1581 #define OPTSET(bit) \
1582 do { \
1583         if (optval) \
1584                 in6p->in6p_flags |= (bit); \
1585         else \
1586                 in6p->in6p_flags &= ~(bit); \
1587 } while (/*CONSTCOND*/ 0)
1588 #define OPTSET2292(bit) \
1589 do { \
1590         in6p->in6p_flags |= IN6P_RFC2292; \
1591         if (optval) \
1592                 in6p->in6p_flags |= (bit); \
1593         else \
1594                 in6p->in6p_flags &= ~(bit); \
1595 } while (/*CONSTCOND*/ 0)
1596 #define OPTBIT(bit) (in6p->in6p_flags & (bit) ? 1 : 0)
1597
1598                                 case IPV6_RECVPKTINFO:
1599                                         /* cannot mix with RFC2292 */
1600                                         if (OPTBIT(IN6P_RFC2292)) {
1601                                                 error = EINVAL;
1602                                                 break;
1603                                         }
1604                                         OPTSET(IN6P_PKTINFO);
1605                                         break;
1606
1607                                 case IPV6_HOPLIMIT:
1608                                 {
1609                                         struct ip6_pktopts **optp;
1610
1611                                         /* cannot mix with RFC2292 */
1612                                         if (OPTBIT(IN6P_RFC2292)) {
1613                                                 error = EINVAL;
1614                                                 break;
1615                                         }
1616                                         optp = &in6p->in6p_outputopts;
1617                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1618                                                            (u_char *)&optval,
1619                                                            sizeof(optval),
1620                                                            optp,
1621                                                            privileged, uproto);
1622                                         break;
1623                                 }
1624
1625                                 case IPV6_RECVHOPLIMIT:
1626                                         /* cannot mix with RFC2292 */
1627                                         if (OPTBIT(IN6P_RFC2292)) {
1628                                                 error = EINVAL;
1629                                                 break;
1630                                         }
1631                                         OPTSET(IN6P_HOPLIMIT);
1632                                         break;
1633
1634                                 case IPV6_RECVHOPOPTS:
1635                                         /* cannot mix with RFC2292 */
1636                                         if (OPTBIT(IN6P_RFC2292)) {
1637                                                 error = EINVAL;
1638                                                 break;
1639                                         }
1640                                         OPTSET(IN6P_HOPOPTS);
1641                                         break;
1642
1643                                 case IPV6_RECVDSTOPTS:
1644                                         /* cannot mix with RFC2292 */
1645                                         if (OPTBIT(IN6P_RFC2292)) {
1646                                                 error = EINVAL;
1647                                                 break;
1648                                         }
1649                                         OPTSET(IN6P_DSTOPTS);
1650                                         break;
1651
1652                                 case IPV6_RECVRTHDRDSTOPTS:
1653                                         /* cannot mix with RFC2292 */
1654                                         if (OPTBIT(IN6P_RFC2292)) {
1655                                                 error = EINVAL;
1656                                                 break;
1657                                         }
1658                                         OPTSET(IN6P_RTHDRDSTOPTS);
1659                                         break;
1660
1661                                 case IPV6_RECVRTHDR:
1662                                         /* cannot mix with RFC2292 */
1663                                         if (OPTBIT(IN6P_RFC2292)) {
1664                                                 error = EINVAL;
1665                                                 break;
1666                                         }
1667                                         OPTSET(IN6P_RTHDR);
1668                                         break;
1669
1670                                 case IPV6_FAITH:
1671                                         OPTSET(IN6P_FAITH);
1672                                         break;
1673
1674                                 case IPV6_RECVPATHMTU:
1675                                         /*
1676                                          * We ignore this option for TCP
1677                                          * sockets.
1678                                          * (rfc2292bis leaves this case
1679                                          * unspecified.)
1680                                          */
1681                                         if (uproto != IPPROTO_TCP)
1682                                                 OPTSET(IN6P_MTU);
1683                                         break;
1684
1685                                 case IPV6_V6ONLY:
1686                                         /*
1687                                          * make setsockopt(IPV6_V6ONLY)
1688                                          * available only prior to bind(2).
1689                                          * see ipng mailing list, Jun 22 2001.
1690                                          */
1691                                         if (in6p->in6p_lport ||
1692                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
1693                                                 error = EINVAL;
1694                                                 break;
1695                                         }
1696                                         OPTSET(IN6P_IPV6_V6ONLY);
1697                                         if (optval)
1698                                                 in6p->in6p_vflag &= ~INP_IPV4;
1699                                         else
1700                                                 in6p->in6p_vflag |= INP_IPV4;
1701                                         break;
1702                                 case IPV6_RECVTCLASS:
1703                                         /* cannot mix with RFC2292 XXX */
1704                                         if (OPTBIT(IN6P_RFC2292)) {
1705                                                 error = EINVAL;
1706                                                 break;
1707                                         }
1708                                         OPTSET(IN6P_TCLASS);
1709                                         break;
1710                                 case IPV6_AUTOFLOWLABEL:
1711                                         OPTSET(IN6P_AUTOFLOWLABEL);
1712                                         break;
1713
1714                                 }
1715                                 break;
1716
1717                         case IPV6_TCLASS:
1718                         case IPV6_DONTFRAG:
1719                         case IPV6_USE_MIN_MTU:
1720                         case IPV6_PREFER_TEMPADDR:
1721                                 if (optlen != sizeof(optval)) {
1722                                         error = EINVAL;
1723                                         break;
1724                                 }
1725                                 error = sooptcopyin(sopt, &optval,
1726                                         sizeof optval, sizeof optval);
1727                                 if (error)
1728                                         break;
1729                                 {
1730                                         struct ip6_pktopts **optp;
1731                                         optp = &in6p->in6p_outputopts;
1732                                         error = ip6_pcbopt(optname,
1733                                                            (u_char *)&optval,
1734                                                            sizeof(optval),
1735                                                            optp,
1736                                                            privileged, uproto);
1737                                         break;
1738                                 }
1739
1740                         case IPV6_2292PKTINFO:
1741                         case IPV6_2292HOPLIMIT:
1742                         case IPV6_2292HOPOPTS:
1743                         case IPV6_2292DSTOPTS:
1744                         case IPV6_2292RTHDR:
1745                                 /* RFC 2292 */
1746                                 if (optlen != sizeof(int)) {
1747                                         error = EINVAL;
1748                                         break;
1749                                 }
1750                                 error = sooptcopyin(sopt, &optval,
1751                                         sizeof optval, sizeof optval);
1752                                 if (error)
1753                                         break;
1754                                 switch (optname) {
1755                                 case IPV6_2292PKTINFO:
1756                                         OPTSET2292(IN6P_PKTINFO);
1757                                         break;
1758                                 case IPV6_2292HOPLIMIT:
1759                                         OPTSET2292(IN6P_HOPLIMIT);
1760                                         break;
1761                                 case IPV6_2292HOPOPTS:
1762                                         /*
1763                                          * Check super-user privilege.
1764                                          * See comments for IPV6_RECVHOPOPTS.
1765                                          */
1766                                         if (!privileged)
1767                                                 return (EPERM);
1768                                         OPTSET2292(IN6P_HOPOPTS);
1769                                         break;
1770                                 case IPV6_2292DSTOPTS:
1771                                         if (!privileged)
1772                                                 return (EPERM);
1773                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1774                                         break;
1775                                 case IPV6_2292RTHDR:
1776                                         OPTSET2292(IN6P_RTHDR);
1777                                         break;
1778                                 }
1779                                 break;
1780                         case IPV6_PKTINFO:
1781                         case IPV6_HOPOPTS:
1782                         case IPV6_RTHDR:
1783                         case IPV6_DSTOPTS:
1784                         case IPV6_RTHDRDSTOPTS:
1785                         case IPV6_NEXTHOP:
1786                         {
1787                                 /* new advanced API (2292bis) */
1788                                 u_char *optbuf;
1789                                 int optlen;
1790                                 struct ip6_pktopts **optp;
1791
1792                                 /* cannot mix with RFC2292 */
1793                                 if (OPTBIT(IN6P_RFC2292)) {
1794                                         error = EINVAL;
1795                                         break;
1796                                 }
1797
1798                                 switch (optname) {
1799                                 case IPV6_HOPOPTS:
1800                                 case IPV6_DSTOPTS:
1801                                 case IPV6_RTHDRDSTOPTS:
1802                                 case IPV6_NEXTHOP:
1803                                         if (!privileged)
1804                                                 error = EPERM;
1805                                         break;
1806                                 }
1807                                 if (error)
1808                                         break;
1809
1810                                 switch (optname) {
1811                                 case IPV6_PKTINFO:
1812                                         optlen = sizeof(struct in6_pktinfo);
1813                                         break;
1814                                 case IPV6_NEXTHOP:
1815                                         optlen = SOCK_MAXADDRLEN;
1816                                         break;
1817                                 default:
1818                                         optlen = IPV6_MAXOPTHDR;
1819                                         break;
1820                                 }
1821                                 if (sopt->sopt_valsize > optlen) {
1822                                         error = EINVAL;
1823                                         break;
1824                                 }
1825
1826                                 optlen = sopt->sopt_valsize;
1827                                 optbuf = malloc(optlen, M_TEMP, M_WAITOK);
1828                                 error = sooptcopyin(sopt, optbuf, optlen,
1829                                     optlen);
1830                                 if (error) {
1831                                         free(optbuf, M_TEMP);
1832                                         break;
1833                                 }
1834
1835                                 optp = &in6p->in6p_outputopts;
1836                                 error = ip6_pcbopt(optname,
1837                                                    optbuf, optlen,
1838                                                    optp, privileged, uproto);
1839                                 free(optbuf, M_TEMP);
1840                                 break;
1841                         }
1842 #undef OPTSET
1843
1844                         case IPV6_MULTICAST_IF:
1845                         case IPV6_MULTICAST_HOPS:
1846                         case IPV6_MULTICAST_LOOP:
1847                         case IPV6_JOIN_GROUP:
1848                         case IPV6_LEAVE_GROUP:
1849                             {
1850                                 if (sopt->sopt_valsize > MLEN) {
1851                                         error = EMSGSIZE;
1852                                         break;
1853                                 }
1854                                 /* XXX */
1855                             }
1856                             /* FALLTHROUGH */
1857                             {
1858                                 struct mbuf *m;
1859
1860                                 if (sopt->sopt_valsize > MCLBYTES) {
1861                                         error = EMSGSIZE;
1862                                         break;
1863                                 }
1864                                 /* XXX */
1865                                 MGET(m, sopt->sopt_td ? M_WAIT : M_DONTWAIT, MT_HEADER);
1866                                 if (m == 0) {
1867                                         error = ENOBUFS;
1868                                         break;
1869                                 }
1870                                 if (sopt->sopt_valsize > MLEN) {
1871                                         MCLGET(m, sopt->sopt_td ? M_WAIT : M_DONTWAIT);
1872                                         if ((m->m_flags & M_EXT) == 0) {
1873                                                 m_free(m);
1874                                                 error = ENOBUFS;
1875                                                 break;
1876                                         }
1877                                 }
1878                                 m->m_len = sopt->sopt_valsize;
1879                                 error = sooptcopyin(sopt, mtod(m, char *),
1880                                                     m->m_len, m->m_len);
1881                                 if (error) {
1882                                         (void)m_free(m);
1883                                         break;
1884                                 }
1885                                 error = ip6_setmoptions(sopt->sopt_name,
1886                                                         &in6p->in6p_moptions,
1887                                                         m);
1888                                 (void)m_free(m);
1889                             }
1890                                 break;
1891
1892                         case IPV6_PORTRANGE:
1893                                 error = sooptcopyin(sopt, &optval,
1894                                     sizeof optval, sizeof optval);
1895                                 if (error)
1896                                         break;
1897
1898                                 switch (optval) {
1899                                 case IPV6_PORTRANGE_DEFAULT:
1900                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1901                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1902                                         break;
1903
1904                                 case IPV6_PORTRANGE_HIGH:
1905                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1906                                         in6p->in6p_flags |= IN6P_HIGHPORT;
1907                                         break;
1908
1909                                 case IPV6_PORTRANGE_LOW:
1910                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1911                                         in6p->in6p_flags |= IN6P_LOWPORT;
1912                                         break;
1913
1914                                 default:
1915                                         error = EINVAL;
1916                                         break;
1917                                 }
1918                                 break;
1919
1920 #if defined(IPSEC) || defined(FAST_IPSEC)
1921                         case IPV6_IPSEC_POLICY:
1922                             {
1923                                 caddr_t req = NULL;
1924                                 size_t len = 0;
1925                                 struct mbuf *m;
1926
1927                                 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1928                                         break;
1929                                 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1930                                         break;
1931                                 if (m) {
1932                                         req = mtod(m, caddr_t);
1933                                         len = m->m_len;
1934                                 }
1935                                 error = ipsec6_set_policy(in6p, optname, req,
1936                                                           len, privileged);
1937                                 m_freem(m);
1938                             }
1939                                 break;
1940 #endif /* KAME IPSEC */
1941
1942                         case IPV6_FW_ADD:
1943                         case IPV6_FW_DEL:
1944                         case IPV6_FW_FLUSH:
1945                         case IPV6_FW_ZERO:
1946                             {
1947                                 struct mbuf *m;
1948                                 struct mbuf **mp = &m;
1949
1950                                 if (ip6_fw_ctl_ptr == NULL)
1951                                         return EINVAL;
1952                                 /* XXX */
1953                                 if ((error = soopt_getm(sopt, &m)) != 0)
1954                                         break;
1955                                 /* XXX */
1956                                 if ((error = soopt_mcopyin(sopt, m)) != 0)
1957                                         break;
1958                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
1959                                 m = *mp;
1960                             }
1961                                 break;
1962
1963                         default:
1964                                 error = ENOPROTOOPT;
1965                                 break;
1966                         }
1967                         break;
1968
1969                 case SOPT_GET:
1970                         switch (optname) {
1971
1972                         case IPV6_2292PKTOPTIONS:
1973 #ifdef IPV6_PKTOPTIONS
1974                         case IPV6_PKTOPTIONS:
1975 #endif
1976                                 /*
1977                                  * RFC3542 (effectively) deprecated the
1978                                  * semantics of the 2292-style pktoptions.
1979                                  * Since it was not reliable in nature (i.e.,
1980                                  * applications had to expect the lack of some
1981                                  * information after all), it would make sense
1982                                  * to simplify this part by always returning
1983                                  * empty data.
1984                                  */
1985                                 sopt->sopt_valsize = 0;
1986                                 break;
1987
1988                         case IPV6_RECVHOPOPTS:
1989                         case IPV6_RECVDSTOPTS:
1990                         case IPV6_RECVRTHDRDSTOPTS:
1991                         case IPV6_UNICAST_HOPS:
1992                         case IPV6_RECVPKTINFO:
1993                         case IPV6_RECVHOPLIMIT:
1994                         case IPV6_RECVRTHDR:
1995                         case IPV6_RECVPATHMTU:
1996
1997                         case IPV6_FAITH:
1998                         case IPV6_V6ONLY:
1999                         case IPV6_PORTRANGE:
2000                         case IPV6_RECVTCLASS:
2001                         case IPV6_AUTOFLOWLABEL:
2002                                 switch (optname) {
2003
2004                                 case IPV6_RECVHOPOPTS:
2005                                         optval = OPTBIT(IN6P_HOPOPTS);
2006                                         break;
2007
2008                                 case IPV6_RECVDSTOPTS:
2009                                         optval = OPTBIT(IN6P_DSTOPTS);
2010                                         break;
2011
2012                                 case IPV6_RECVRTHDRDSTOPTS:
2013                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2014                                         break;
2015
2016                                 case IPV6_UNICAST_HOPS:
2017                                         optval = in6p->in6p_hops;
2018                                         break;
2019
2020                                 case IPV6_RECVPKTINFO:
2021                                         optval = OPTBIT(IN6P_PKTINFO);
2022                                         break;
2023
2024                                 case IPV6_RECVHOPLIMIT:
2025                                         optval = OPTBIT(IN6P_HOPLIMIT);
2026                                         break;
2027
2028                                 case IPV6_RECVRTHDR:
2029                                         optval = OPTBIT(IN6P_RTHDR);
2030                                         break;
2031
2032                                 case IPV6_RECVPATHMTU:
2033                                         optval = OPTBIT(IN6P_MTU);
2034                                         break;
2035
2036                                 case IPV6_FAITH:
2037                                         optval = OPTBIT(IN6P_FAITH);
2038                                         break;
2039
2040                                 case IPV6_V6ONLY:
2041                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2042                                         break;
2043
2044                                 case IPV6_PORTRANGE:
2045                                     {
2046                                         int flags;
2047                                         flags = in6p->in6p_flags;
2048                                         if (flags & IN6P_HIGHPORT)
2049                                                 optval = IPV6_PORTRANGE_HIGH;
2050                                         else if (flags & IN6P_LOWPORT)
2051                                                 optval = IPV6_PORTRANGE_LOW;
2052                                         else
2053                                                 optval = 0;
2054                                         break;
2055                                     }
2056                                 case IPV6_RECVTCLASS:
2057                                         optval = OPTBIT(IN6P_TCLASS);
2058                                         break;
2059
2060                                 case IPV6_AUTOFLOWLABEL:
2061                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2062                                         break;
2063                                 }
2064                                 if (error)
2065                                         break;
2066                                 error = sooptcopyout(sopt, &optval,
2067                                         sizeof optval);
2068                                 break;
2069
2070                         case IPV6_PATHMTU:
2071                         {
2072                                 u_long pmtu = 0;
2073                                 struct ip6_mtuinfo mtuinfo;
2074                                 struct route_in6 sro;
2075
2076                                 bzero(&sro, sizeof(sro));
2077
2078                                 if (!(so->so_state & SS_ISCONNECTED))
2079                                         return (ENOTCONN);
2080                                 /*
2081                                  * XXX: we dot not consider the case of source
2082                                  * routing, or optional information to specify
2083                                  * the outgoing interface.
2084                                  */
2085                                 error = ip6_getpmtu(&sro, NULL, NULL,
2086                                     &in6p->in6p_faddr, &pmtu, NULL);
2087                                 if (sro.ro_rt)
2088                                         RTFREE(sro.ro_rt);
2089                                 if (error)
2090                                         break;
2091                                 if (pmtu > IPV6_MAXPACKET)
2092                                         pmtu = IPV6_MAXPACKET;
2093
2094                                 bzero(&mtuinfo, sizeof(mtuinfo));
2095                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2096                                 optdata = (void *)&mtuinfo;
2097                                 optdatalen = sizeof(mtuinfo);
2098                                 error = sooptcopyout(sopt, optdata,
2099                                     optdatalen);
2100                                 break;
2101                         }
2102
2103                         case IPV6_2292PKTINFO:
2104                         case IPV6_2292HOPLIMIT:
2105                         case IPV6_2292HOPOPTS:
2106                         case IPV6_2292RTHDR:
2107                         case IPV6_2292DSTOPTS:
2108                                 switch (optname) {
2109                                 case IPV6_2292PKTINFO:
2110                                         optval = OPTBIT(IN6P_PKTINFO);
2111                                         break;
2112                                 case IPV6_2292HOPLIMIT:
2113                                         optval = OPTBIT(IN6P_HOPLIMIT);
2114                                         break;
2115                                 case IPV6_2292HOPOPTS:
2116                                         optval = OPTBIT(IN6P_HOPOPTS);
2117                                         break;
2118                                 case IPV6_2292RTHDR:
2119                                         optval = OPTBIT(IN6P_RTHDR);
2120                                         break;
2121                                 case IPV6_2292DSTOPTS:
2122                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2123                                         break;
2124                                 }
2125                                 error = sooptcopyout(sopt, &optval,
2126                                     sizeof optval);
2127                                 break;
2128                         case IPV6_PKTINFO:
2129                         case IPV6_HOPOPTS:
2130                         case IPV6_RTHDR:
2131                         case IPV6_DSTOPTS:
2132                         case IPV6_RTHDRDSTOPTS:
2133                         case IPV6_NEXTHOP:
2134                         case IPV6_TCLASS:
2135                         case IPV6_DONTFRAG:
2136                         case IPV6_USE_MIN_MTU:
2137                         case IPV6_PREFER_TEMPADDR:
2138                                 error = ip6_getpcbopt(in6p->in6p_outputopts,
2139                                     optname, sopt);
2140                                 break;
2141
2142                         case IPV6_MULTICAST_IF:
2143                         case IPV6_MULTICAST_HOPS:
2144                         case IPV6_MULTICAST_LOOP:
2145                         case IPV6_JOIN_GROUP:
2146                         case IPV6_LEAVE_GROUP:
2147                             {
2148                                 struct mbuf *m;
2149                                 error = ip6_getmoptions(sopt->sopt_name,
2150                                     in6p->in6p_moptions, &m);
2151                                 if (error == 0)
2152                                         error = sooptcopyout(sopt,
2153                                             mtod(m, char *), m->m_len);
2154                                 m_freem(m);
2155                             }
2156                                 break;
2157
2158 #if defined(IPSEC) || defined(FAST_IPSEC)
2159                         case IPV6_IPSEC_POLICY:
2160                           {
2161                                 caddr_t req = NULL;
2162                                 size_t len = 0;
2163                                 struct mbuf *m = NULL;
2164                                 struct mbuf **mp = &m;
2165                                 size_t ovalsize = sopt->sopt_valsize;
2166                                 caddr_t oval = (caddr_t)sopt->sopt_val;
2167
2168                                 error = soopt_getm(sopt, &m); /* XXX */
2169                                 if (error != 0)
2170                                         break;
2171                                 error = soopt_mcopyin(sopt, m); /* XXX */
2172                                 if (error != 0)
2173                                         break;
2174                                 sopt->sopt_valsize = ovalsize;
2175                                 sopt->sopt_val = oval;
2176                                 if (m) {
2177                                         req = mtod(m, caddr_t);
2178                                         len = m->m_len;
2179                                 }
2180                                 error = ipsec6_get_policy(in6p, req, len, mp);
2181                                 if (error == 0)
2182                                         error = soopt_mcopyout(sopt, m); /* XXX */
2183                                 if (error == 0 && m)
2184                                         m_freem(m);
2185                                 break;
2186                           }
2187 #endif /* KAME IPSEC */
2188
2189                         case IPV6_FW_GET:
2190                           {
2191                                 struct mbuf *m;
2192                                 struct mbuf **mp = &m;
2193
2194                                 if (ip6_fw_ctl_ptr == NULL)
2195                                 {
2196                                         return EINVAL;
2197                                 }
2198                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
2199                                 if (error == 0)
2200                                         error = soopt_mcopyout(sopt, m); /* XXX */
2201                                 if (error == 0 && m)
2202                                         m_freem(m);
2203                           }
2204                                 break;
2205
2206                         default:
2207                                 error = ENOPROTOOPT;
2208                                 break;
2209                         }
2210                         break;
2211                 }
2212         } else {                /* level != IPPROTO_IPV6 */
2213                 error = EINVAL;
2214         }
2215         return (error);
2216 }
2217
2218 int
2219 ip6_raw_ctloutput(so, sopt)
2220         struct socket *so;
2221         struct sockopt *sopt;
2222 {
2223         int error = 0, optval, optlen;
2224         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2225         struct in6pcb *in6p = sotoin6pcb(so);
2226         int level, op, optname;
2227
2228         if (sopt) {
2229                 level = sopt->sopt_level;
2230                 op = sopt->sopt_dir;
2231                 optname = sopt->sopt_name;
2232                 optlen = sopt->sopt_valsize;
2233         } else
2234                 panic("ip6_raw_ctloutput: arg soopt is NULL");
2235
2236         if (level != IPPROTO_IPV6) {
2237                 return (EINVAL);
2238         }
2239
2240         switch (optname) {
2241         case IPV6_CHECKSUM:
2242                 /*
2243                  * For ICMPv6 sockets, no modification allowed for checksum
2244                  * offset, permit "no change" values to help existing apps.
2245                  *
2246                  * XXX 2292bis says: "An attempt to set IPV6_CHECKSUM
2247                  * for an ICMPv6 socket will fail."
2248                  * The current behavior does not meet 2292bis.
2249                  */
2250                 switch (op) {
2251                 case SOPT_SET:
2252                         if (optlen != sizeof(int)) {
2253                                 error = EINVAL;
2254                                 break;
2255                         }
2256                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2257                                             sizeof(optval));
2258                         if (error)
2259                                 break;
2260                         if ((optval % 2) != 0) {
2261                                 /* the API assumes even offset values */
2262                                 error = EINVAL;
2263                         } else if (so->so_proto->pr_protocol ==
2264                             IPPROTO_ICMPV6) {
2265                                 if (optval != icmp6off)
2266                                         error = EINVAL;
2267                         } else
2268                                 in6p->in6p_cksum = optval;
2269                         break;
2270
2271                 case SOPT_GET:
2272                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2273                                 optval = icmp6off;
2274                         else
2275                                 optval = in6p->in6p_cksum;
2276
2277                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2278                         break;
2279
2280                 default:
2281                         error = EINVAL;
2282                         break;
2283                 }
2284                 break;
2285
2286         default:
2287                 error = ENOPROTOOPT;
2288                 break;
2289         }
2290
2291         return (error);
2292 }
2293
2294 /*
2295  * Set up IP6 options in pcb for insertion in output packets or
2296  * specifying behavior of outgoing packets.
2297  */
2298 static int
2299 ip6_pcbopts(pktopt, m, so, sopt)
2300         struct ip6_pktopts **pktopt;
2301         struct mbuf *m;
2302         struct socket *so;
2303         struct sockopt *sopt;
2304 {
2305         struct ip6_pktopts *opt = *pktopt;
2306         int error = 0;
2307         struct thread *td = sopt->sopt_td;
2308         int priv = 0;
2309
2310         /* turn off any old options. */
2311         if (opt) {
2312 #ifdef DIAGNOSTIC
2313                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2314                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2315                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2316                         printf("ip6_pcbopts: all specified options are cleared.\n");
2317 #endif
2318                 ip6_clearpktopts(opt, -1);
2319         } else
2320                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2321         *pktopt = NULL;
2322
2323         if (!m || m->m_len == 0) {
2324                 /*
2325                  * Only turning off any previous options, regardless of
2326                  * whether the opt is just created or given.
2327                  */
2328                 free(opt, M_IP6OPT);
2329                 return (0);
2330         }
2331
2332         /*  set options specified by user. */
2333         if (td && !suser(td))
2334                 priv = 1;
2335         if ((error = ip6_setpktoptions(m, opt, NULL, priv, 1,
2336             so->so_proto->pr_protocol)) != 0) {
2337                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2338                 free(opt, M_IP6OPT);
2339                 return (error);
2340         }
2341         *pktopt = opt;
2342         return (0);
2343 }
2344
2345 /*
2346  * initialize ip6_pktopts.  beware that there are non-zero default values in
2347  * the struct.
2348  */
2349 void
2350 init_ip6pktopts(opt)
2351         struct ip6_pktopts *opt;
2352 {
2353
2354         bzero(opt, sizeof(*opt));
2355         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2356         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2357         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2358         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2359 }
2360
2361 static int
2362 ip6_pcbopt(optname, buf, len, pktopt, priv, uproto)
2363         int optname, len, priv;
2364         u_char *buf;
2365         struct ip6_pktopts **pktopt;
2366         int uproto;
2367 {
2368         struct ip6_pktopts *opt;
2369
2370         if (*pktopt == NULL) {
2371                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2372                     M_WAITOK);
2373                 init_ip6pktopts(*pktopt);
2374                 (*pktopt)->needfree = 1;
2375         }
2376         opt = *pktopt;
2377
2378         return (ip6_setpktoption(optname, buf, len, opt, priv, 1, 0, uproto));
2379 }
2380
2381 static int
2382 ip6_getpcbopt(pktopt, optname, sopt)
2383         struct ip6_pktopts *pktopt;
2384         struct sockopt *sopt;
2385         int optname;
2386 {
2387         void *optdata = NULL;
2388         int optdatalen = 0;
2389         struct ip6_ext *ip6e;
2390         int error = 0;
2391         struct in6_pktinfo null_pktinfo;
2392         int deftclass = 0, on;
2393         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2394         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2395
2396         switch (optname) {
2397         case IPV6_PKTINFO:
2398                 if (pktopt && pktopt->ip6po_pktinfo)
2399                         optdata = (void *)pktopt->ip6po_pktinfo;
2400                 else {
2401                         /* XXX: we don't have to do this every time... */
2402                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2403                         optdata = (void *)&null_pktinfo;
2404                 }
2405                 optdatalen = sizeof(struct in6_pktinfo);
2406                 break;
2407         case IPV6_TCLASS:
2408                 if (pktopt && pktopt->ip6po_tclass >= 0)
2409                         optdata = (void *)&pktopt->ip6po_tclass;
2410                 else
2411                         optdata = (void *)&deftclass;
2412                 optdatalen = sizeof(int);
2413                 break;
2414         case IPV6_HOPOPTS:
2415                 if (pktopt && pktopt->ip6po_hbh) {
2416                         optdata = (void *)pktopt->ip6po_hbh;
2417                         ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
2418                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2419                 }
2420                 break;
2421         case IPV6_RTHDR:
2422                 if (pktopt && pktopt->ip6po_rthdr) {
2423                         optdata = (void *)pktopt->ip6po_rthdr;
2424                         ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
2425                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2426                 }
2427                 break;
2428         case IPV6_RTHDRDSTOPTS:
2429                 if (pktopt && pktopt->ip6po_dest1) {
2430                         optdata = (void *)pktopt->ip6po_dest1;
2431                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
2432                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2433                 }
2434                 break;
2435         case IPV6_DSTOPTS:
2436                 if (pktopt && pktopt->ip6po_dest2) {
2437                         optdata = (void *)pktopt->ip6po_dest2;
2438                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
2439                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2440                 }
2441                 break;
2442         case IPV6_NEXTHOP:
2443                 if (pktopt && pktopt->ip6po_nexthop) {
2444                         optdata = (void *)pktopt->ip6po_nexthop;
2445                         optdatalen = pktopt->ip6po_nexthop->sa_len;
2446                 }
2447                 break;
2448         case IPV6_USE_MIN_MTU:
2449                 if (pktopt)
2450                         optdata = (void *)&pktopt->ip6po_minmtu;
2451                 else
2452                         optdata = (void *)&defminmtu;
2453                 optdatalen = sizeof(int);
2454                 break;
2455         case IPV6_DONTFRAG:
2456                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2457                         on = 1;
2458                 else
2459                         on = 0;
2460                 optdata = (void *)&on;
2461                 optdatalen = sizeof(on);
2462                 break;
2463         case IPV6_PREFER_TEMPADDR:
2464                 if (pktopt)
2465                         optdata = (void *)&pktopt->ip6po_prefer_tempaddr;
2466                 else
2467                         optdata = (void *)&defpreftemp;
2468                 optdatalen = sizeof(int);
2469                 break;
2470         default:                /* should not happen */
2471 #ifdef DIAGNOSTIC
2472                 panic("ip6_getpcbopt: unexpected option\n");
2473 #endif
2474                 return (ENOPROTOOPT);
2475         }
2476
2477         error = sooptcopyout(sopt, optdata, optdatalen);
2478
2479         return (error);
2480 }
2481
2482 void
2483 ip6_clearpktopts(pktopt, optname)
2484         struct ip6_pktopts *pktopt;
2485         int optname;
2486 {
2487         int needfree;
2488
2489         if (pktopt == NULL)
2490                 return;
2491
2492         needfree = pktopt->needfree;
2493
2494         if (optname == -1 || optname == IPV6_PKTINFO) {
2495                 if (needfree && pktopt->ip6po_pktinfo)
2496                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2497                 pktopt->ip6po_pktinfo = NULL;
2498         }
2499         if (optname == -1 || optname == IPV6_HOPLIMIT)
2500                 pktopt->ip6po_hlim = -1;
2501         if (optname == -1 || optname == IPV6_TCLASS)
2502                 pktopt->ip6po_tclass = -1;
2503         if (optname == -1 || optname == IPV6_NEXTHOP) {
2504                 if (pktopt->ip6po_nextroute.ro_rt) {
2505                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2506                         pktopt->ip6po_nextroute.ro_rt = NULL;
2507                 }
2508                 if (needfree && pktopt->ip6po_nexthop)
2509                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2510                 pktopt->ip6po_nexthop = NULL;
2511         }
2512         if (optname == -1 || optname == IPV6_HOPOPTS) {
2513                 if (needfree && pktopt->ip6po_hbh)
2514                         free(pktopt->ip6po_hbh, M_IP6OPT);
2515                 pktopt->ip6po_hbh = NULL;
2516         }
2517         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2518                 if (needfree && pktopt->ip6po_dest1)
2519                         free(pktopt->ip6po_dest1, M_IP6OPT);
2520                 pktopt->ip6po_dest1 = NULL;
2521         }
2522         if (optname == -1 || optname == IPV6_RTHDR) {
2523                 if (needfree && pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2524                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2525                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2526                 if (pktopt->ip6po_route.ro_rt) {
2527                         RTFREE(pktopt->ip6po_route.ro_rt);
2528                         pktopt->ip6po_route.ro_rt = NULL;
2529                 }
2530         }
2531         if (optname == -1 || optname == IPV6_DSTOPTS) {
2532                 if (needfree && pktopt->ip6po_dest2)
2533                         free(pktopt->ip6po_dest2, M_IP6OPT);
2534                 pktopt->ip6po_dest2 = NULL;
2535         }
2536 }
2537
2538 #define PKTOPT_EXTHDRCPY(type) \
2539 do {\
2540         if (src->type) {\
2541                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2542                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2543                 if (dst->type == NULL && canwait == M_NOWAIT)\
2544                         goto bad;\
2545                 bcopy(src->type, dst->type, hlen);\
2546         }\
2547 } while (/*CONSTCOND*/ 0)
2548
2549 struct ip6_pktopts *
2550 ip6_copypktopts(src, canwait)
2551         struct ip6_pktopts *src;
2552         int canwait;
2553 {
2554         struct ip6_pktopts *dst;
2555
2556         if (src == NULL) {
2557                 printf("ip6_clearpktopts: invalid argument\n");
2558                 return (NULL);
2559         }
2560
2561         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2562         if (dst == NULL && canwait == M_NOWAIT)
2563                 return (NULL);
2564         bzero(dst, sizeof(*dst));
2565         dst->needfree = 1;
2566
2567         dst->ip6po_hlim = src->ip6po_hlim;
2568         dst->ip6po_tclass = src->ip6po_tclass;
2569         dst->ip6po_flags = src->ip6po_flags;
2570         if (src->ip6po_pktinfo) {
2571                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2572                     M_IP6OPT, canwait);
2573                 if (dst->ip6po_pktinfo == NULL && canwait == M_NOWAIT)
2574                         goto bad;
2575                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2576         }
2577         if (src->ip6po_nexthop) {
2578                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2579                     M_IP6OPT, canwait);
2580                 if (dst->ip6po_nexthop == NULL && canwait == M_NOWAIT)
2581                         goto bad;
2582                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2583                     src->ip6po_nexthop->sa_len);
2584         }
2585         PKTOPT_EXTHDRCPY(ip6po_hbh);
2586         PKTOPT_EXTHDRCPY(ip6po_dest1);
2587         PKTOPT_EXTHDRCPY(ip6po_dest2);
2588         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2589         return (dst);
2590
2591   bad:
2592         if (dst->ip6po_pktinfo) free(dst->ip6po_pktinfo, M_IP6OPT);
2593         if (dst->ip6po_nexthop) free(dst->ip6po_nexthop, M_IP6OPT);
2594         if (dst->ip6po_hbh) free(dst->ip6po_hbh, M_IP6OPT);
2595         if (dst->ip6po_dest1) free(dst->ip6po_dest1, M_IP6OPT);
2596         if (dst->ip6po_dest2) free(dst->ip6po_dest2, M_IP6OPT);
2597         if (dst->ip6po_rthdr) free(dst->ip6po_rthdr, M_IP6OPT);
2598         free(dst, M_IP6OPT);
2599         return (NULL);
2600 }
2601 #undef PKTOPT_EXTHDRCPY
2602
2603 void
2604 ip6_freepcbopts(pktopt)
2605         struct ip6_pktopts *pktopt;
2606 {
2607         if (pktopt == NULL)
2608                 return;
2609
2610         ip6_clearpktopts(pktopt, -1);
2611
2612         free(pktopt, M_IP6OPT);
2613 }
2614
2615 /*
2616  * Set the IP6 multicast options in response to user setsockopt().
2617  */
2618 static int
2619 ip6_setmoptions(optname, im6op, m)
2620         int optname;
2621         struct ip6_moptions **im6op;
2622         struct mbuf *m;
2623 {
2624         int error = 0;
2625         u_int loop, ifindex;
2626         struct ipv6_mreq *mreq;
2627         struct ifnet *ifp;
2628         struct ip6_moptions *im6o = *im6op;
2629         struct route_in6 ro;
2630         struct sockaddr_in6 *dst;
2631         struct in6_multi_mship *imm;
2632         struct thread *td = curthread;
2633
2634         if (im6o == NULL) {
2635                 /*
2636                  * No multicast option buffer attached to the pcb;
2637                  * allocate one and initialize to default values.
2638                  */
2639                 im6o = (struct ip6_moptions *)
2640                         malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK);
2641
2642                 if (im6o == NULL)
2643                         return (ENOBUFS);
2644                 *im6op = im6o;
2645                 im6o->im6o_multicast_ifp = NULL;
2646                 im6o->im6o_multicast_hlim = ip6_defmcasthlim;
2647                 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP;
2648                 LIST_INIT(&im6o->im6o_memberships);
2649         }
2650
2651         switch (optname) {
2652
2653         case IPV6_MULTICAST_IF:
2654                 /*
2655                  * Select the interface for outgoing multicast packets.
2656                  */
2657                 if (m == NULL || m->m_len != sizeof(u_int)) {
2658                         error = EINVAL;
2659                         break;
2660                 }
2661                 bcopy(mtod(m, u_int *), &ifindex, sizeof(ifindex));
2662                 if (ifindex < 0 || if_index < ifindex) {
2663                         error = ENXIO;  /* XXX EINVAL? */
2664                         break;
2665                 }
2666                 ifp = ifnet_byindex(ifindex);
2667                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
2668                         error = EADDRNOTAVAIL;
2669                         break;
2670                 }
2671                 im6o->im6o_multicast_ifp = ifp;
2672                 break;
2673
2674         case IPV6_MULTICAST_HOPS:
2675             {
2676                 /*
2677                  * Set the IP6 hoplimit for outgoing multicast packets.
2678                  */
2679                 int optval;
2680                 if (m == NULL || m->m_len != sizeof(int)) {
2681                         error = EINVAL;
2682                         break;
2683                 }
2684                 bcopy(mtod(m, u_int *), &optval, sizeof(optval));
2685                 if (optval < -1 || optval >= 256)
2686                         error = EINVAL;
2687                 else if (optval == -1)
2688                         im6o->im6o_multicast_hlim = ip6_defmcasthlim;
2689                 else
2690                         im6o->im6o_multicast_hlim = optval;
2691                 break;
2692             }
2693
2694         case IPV6_MULTICAST_LOOP:
2695                 /*
2696                  * Set the loopback flag for outgoing multicast packets.
2697                  * Must be zero or one.
2698                  */
2699                 if (m == NULL || m->m_len != sizeof(u_int)) {
2700                         error = EINVAL;
2701                         break;
2702                 }
2703                 bcopy(mtod(m, u_int *), &loop, sizeof(loop));
2704                 if (loop > 1) {
2705                         error = EINVAL;
2706                         break;
2707                 }
2708                 im6o->im6o_multicast_loop = loop;
2709                 break;
2710
2711         case IPV6_JOIN_GROUP:
2712                 /*
2713                  * Add a multicast group membership.
2714                  * Group must be a valid IP6 multicast address.
2715                  */
2716                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2717                         error = EINVAL;
2718                         break;
2719                 }
2720                 mreq = mtod(m, struct ipv6_mreq *);
2721                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2722                         /*
2723                          * We use the unspecified address to specify to accept
2724                          * all multicast addresses. Only super user is allowed
2725                          * to do this.
2726                          */
2727                         if (suser(td)) {
2728                                 error = EACCES;
2729                                 break;
2730                         }
2731                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2732                         error = EINVAL;
2733                         break;
2734                 }
2735
2736                 /*
2737                  * If the interface is specified, validate it.
2738                  */
2739                 if (mreq->ipv6mr_interface < 0 ||
2740                     if_index < mreq->ipv6mr_interface) {
2741                         error = ENXIO;  /* XXX EINVAL? */
2742                         break;
2743                 }
2744                 /*
2745                  * If no interface was explicitly specified, choose an
2746                  * appropriate one according to the given multicast address.
2747                  */
2748                 if (mreq->ipv6mr_interface == 0) {
2749                         /*
2750                          * If the multicast address is in node-local scope,
2751                          * the interface should be a loopback interface.
2752                          * Otherwise, look up the routing table for the
2753                          * address, and choose the outgoing interface.
2754                          *   XXX: is it a good approach?
2755                          */
2756                         if (IN6_IS_ADDR_MC_INTFACELOCAL(&mreq->ipv6mr_multiaddr)) {
2757                                 ifp = &loif[0];
2758                         } else {
2759                                 ro.ro_rt = NULL;
2760                                 dst = (struct sockaddr_in6 *)&ro.ro_dst;
2761                                 bzero(dst, sizeof(*dst));
2762                                 dst->sin6_len = sizeof(struct sockaddr_in6);
2763                                 dst->sin6_family = AF_INET6;
2764                                 dst->sin6_addr = mreq->ipv6mr_multiaddr;
2765                                 rtalloc((struct route *)&ro);
2766                                 if (ro.ro_rt == NULL) {
2767                                         error = EADDRNOTAVAIL;
2768                                         break;
2769                                 }
2770                                 ifp = ro.ro_rt->rt_ifp;
2771                                 RTFREE(ro.ro_rt);
2772                         }
2773                 } else
2774                         ifp = ifnet_byindex(mreq->ipv6mr_interface);
2775
2776                 /*
2777                  * See if we found an interface, and confirm that it
2778                  * supports multicast
2779                  */
2780                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
2781                         error = EADDRNOTAVAIL;
2782                         break;
2783                 }
2784                 /*
2785                  * Put interface index into the multicast address,
2786                  * if the address has link-local scope.
2787                  */
2788                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2789                         mreq->ipv6mr_multiaddr.s6_addr16[1] =
2790                             htons(ifp->if_index);
2791                 }
2792                 /*
2793                  * See if the membership already exists.
2794                  */
2795                 for (imm = im6o->im6o_memberships.lh_first;
2796                      imm != NULL; imm = imm->i6mm_chain.le_next)
2797                         if (imm->i6mm_maddr->in6m_ifp == ifp &&
2798                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2799                                                &mreq->ipv6mr_multiaddr))
2800                                 break;
2801                 if (imm != NULL) {
2802                         error = EADDRINUSE;
2803                         break;
2804                 }
2805                 /*
2806                  * Everything looks good; add a new record to the multicast
2807                  * address list for the given interface.
2808                  */
2809                 imm = malloc(sizeof(*imm), M_IPMADDR, M_WAITOK);
2810                 if (imm == NULL) {
2811                         error = ENOBUFS;
2812                         break;
2813                 }
2814                 if ((imm->i6mm_maddr =
2815                      in6_addmulti(&mreq->ipv6mr_multiaddr, ifp, &error)) == NULL) {
2816                         free(imm, M_IPMADDR);
2817                         break;
2818                 }
2819                 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
2820                 break;
2821
2822         case IPV6_LEAVE_GROUP:
2823                 /*
2824                  * Drop a multicast group membership.
2825                  * Group must be a valid IP6 multicast address.
2826                  */
2827                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2828                         error = EINVAL;
2829                         break;
2830                 }
2831                 mreq = mtod(m, struct ipv6_mreq *);
2832                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2833                         if (suser(td)) {
2834                                 error = EACCES;
2835                                 break;
2836                         }
2837                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2838                         error = EINVAL;
2839                         break;
2840                 }
2841                 /*
2842                  * If an interface address was specified, get a pointer
2843                  * to its ifnet structure.
2844                  */
2845                 if (mreq->ipv6mr_interface < 0
2846                  || if_index < mreq->ipv6mr_interface) {
2847                         error = ENXIO;  /* XXX EINVAL? */
2848                         break;
2849                 }
2850                 ifp = ifnet_byindex(mreq->ipv6mr_interface);
2851                 /*
2852                  * Put interface index into the multicast address,
2853                  * if the address has link-local scope.
2854                  */
2855                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2856                         mreq->ipv6mr_multiaddr.s6_addr16[1]
2857                                 = htons(mreq->ipv6mr_interface);
2858                 }
2859
2860                 /*
2861                  * Find the membership in the membership list.
2862                  */
2863                 for (imm = im6o->im6o_memberships.lh_first;
2864                      imm != NULL; imm = imm->i6mm_chain.le_next) {
2865                         if ((ifp == NULL || imm->i6mm_maddr->in6m_ifp == ifp) &&
2866                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2867                             &mreq->ipv6mr_multiaddr))
2868                                 break;
2869                 }
2870                 if (imm == NULL) {
2871                         /* Unable to resolve interface */
2872                         error = EADDRNOTAVAIL;
2873                         break;
2874                 }
2875                 /*
2876                  * Give up the multicast address record to which the
2877                  * membership points.
2878                  */
2879                 LIST_REMOVE(imm, i6mm_chain);
2880                 in6_delmulti(imm->i6mm_maddr);
2881                 free(imm, M_IPMADDR);
2882                 break;
2883
2884         default:
2885                 error = EOPNOTSUPP;
2886                 break;
2887         }
2888
2889         /*
2890          * If all options have default values, no need to keep the mbuf.
2891          */
2892         if (im6o->im6o_multicast_ifp == NULL &&
2893             im6o->im6o_multicast_hlim == ip6_defmcasthlim &&
2894             im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP &&
2895             im6o->im6o_memberships.lh_first == NULL) {
2896                 free(*im6op, M_IPMOPTS);
2897                 *im6op = NULL;
2898         }
2899
2900         return (error);
2901 }
2902
2903 /*
2904  * Return the IP6 multicast options in response to user getsockopt().
2905  */
2906 static int
2907 ip6_getmoptions(optname, im6o, mp)
2908         int optname;
2909         struct ip6_moptions *im6o;
2910         struct mbuf **mp;
2911 {
2912         u_int *hlim, *loop, *ifindex;
2913
2914         *mp = m_get(M_TRYWAIT, MT_HEADER);              /* XXX */
2915
2916         switch (optname) {
2917
2918         case IPV6_MULTICAST_IF:
2919                 ifindex = mtod(*mp, u_int *);
2920                 (*mp)->m_len = sizeof(u_int);
2921                 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL)
2922                         *ifindex = 0;
2923                 else
2924                         *ifindex = im6o->im6o_multicast_ifp->if_index;
2925                 return (0);
2926
2927         case IPV6_MULTICAST_HOPS:
2928                 hlim = mtod(*mp, u_int *);
2929                 (*mp)->m_len = sizeof(u_int);
2930                 if (im6o == NULL)
2931                         *hlim = ip6_defmcasthlim;
2932                 else
2933                         *hlim = im6o->im6o_multicast_hlim;
2934                 return (0);
2935
2936         case IPV6_MULTICAST_LOOP:
2937                 loop = mtod(*mp, u_int *);
2938                 (*mp)->m_len = sizeof(u_int);
2939                 if (im6o == NULL)
2940                         *loop = ip6_defmcasthlim;
2941                 else
2942                         *loop = im6o->im6o_multicast_loop;
2943                 return (0);
2944
2945         default:
2946                 return (EOPNOTSUPP);
2947         }
2948 }
2949
2950 /*
2951  * Discard the IP6 multicast options.
2952  */
2953 void
2954 ip6_freemoptions(im6o)
2955         struct ip6_moptions *im6o;
2956 {
2957         struct in6_multi_mship *imm;
2958
2959         if (im6o == NULL)
2960                 return;
2961
2962         while ((imm = im6o->im6o_memberships.lh_first) != NULL) {
2963                 LIST_REMOVE(imm, i6mm_chain);
2964                 if (imm->i6mm_maddr)
2965                         in6_delmulti(imm->i6mm_maddr);
2966                 free(imm, M_IPMADDR);
2967         }
2968         free(im6o, M_IPMOPTS);
2969 }
2970
2971 /*
2972  * Set IPv6 outgoing packet options based on advanced API.
2973  */
2974 int
2975 ip6_setpktoptions(control, opt, stickyopt, priv, needcopy, uproto)
2976         struct mbuf *control;
2977         struct ip6_pktopts *opt, *stickyopt;
2978         int priv, needcopy, uproto;
2979 {
2980         struct cmsghdr *cm = 0;
2981
2982         if (control == 0 || opt == 0)
2983                 return (EINVAL);
2984
2985         if (stickyopt) {
2986                 /*
2987                  * If stickyopt is provided, make a local copy of the options
2988                  * for this particular packet, then override them by ancillary
2989                  * objects.
2990                  * XXX: need to gain a reference for the cached route of the
2991                  * next hop in case of the overriding.
2992                  */
2993                 *opt = *stickyopt;
2994                 if (opt->ip6po_nextroute.ro_rt) {
2995                         RT_LOCK(opt->ip6po_nextroute.ro_rt);
2996                         RT_ADDREF(opt->ip6po_nextroute.ro_rt);
2997                         RT_UNLOCK(opt->ip6po_nextroute.ro_rt);
2998                 }
2999         } else
3000                 init_ip6pktopts(opt);
3001         opt->needfree = needcopy;
3002
3003         /*
3004          * XXX: Currently, we assume all the optional information is stored
3005          * in a single mbuf.
3006          */
3007         if (control->m_next)
3008                 return (EINVAL);
3009
3010         for (; control->m_len; control->m_data += CMSG_ALIGN(cm->cmsg_len),
3011             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
3012                 int error;
3013
3014                 if (control->m_len < CMSG_LEN(0))
3015                         return (EINVAL);
3016
3017                 cm = mtod(control, struct cmsghdr *);
3018                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
3019                         return (EINVAL);
3020                 if (cm->cmsg_level != IPPROTO_IPV6)
3021                         continue;
3022
3023                 error = ip6_setpktoption(cm->cmsg_type, CMSG_DATA(cm),
3024                     cm->cmsg_len - CMSG_LEN(0), opt, priv, needcopy, 1, uproto);
3025                 if (error)
3026                         return (error);
3027         }
3028
3029         return (0);
3030 }
3031
3032 /*
3033  * Set a particular packet option, as a sticky option or an ancillary data
3034  * item.  "len" can be 0 only when it's a sticky option.
3035  * We have 4 cases of combination of "sticky" and "cmsg":
3036  * "sticky=0, cmsg=0": impossible
3037  * "sticky=0, cmsg=1": RFC2292 or rfc2292bis ancillary data
3038  * "sticky=1, cmsg=0": rfc2292bis socket option
3039  * "sticky=1, cmsg=1": RFC2292 socket option
3040  */
3041 static int
3042 ip6_setpktoption(optname, buf, len, opt, priv, sticky, cmsg, uproto)
3043         int optname, len, priv, sticky, cmsg, uproto;
3044         u_char *buf;
3045         struct ip6_pktopts *opt;
3046 {
3047         int minmtupolicy, preftemp;
3048
3049         if (!sticky && !cmsg) {
3050 #ifdef DIAGNOSTIC
3051                 printf("ip6_setpktoption: impossible case\n");
3052 #endif
3053                 return (EINVAL);
3054         }
3055
3056         /*
3057          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
3058          * not be specified in the context of rfc2292bis.  Conversely,
3059          * rfc2292bis types should not be specified in the context of RFC2292.
3060          */
3061         if (!cmsg) {
3062                 switch (optname) {
3063                 case IPV6_2292PKTINFO:
3064                 case IPV6_2292HOPLIMIT:
3065                 case IPV6_2292NEXTHOP:
3066                 case IPV6_2292HOPOPTS:
3067                 case IPV6_2292DSTOPTS:
3068                 case IPV6_2292RTHDR:
3069                 case IPV6_2292PKTOPTIONS:
3070                         return (ENOPROTOOPT);
3071                 }
3072         }
3073         if (sticky && cmsg) {
3074                 switch (optname) {
3075                 case IPV6_PKTINFO:
3076                 case IPV6_HOPLIMIT:
3077                 case IPV6_NEXTHOP:
3078                 case IPV6_HOPOPTS:
3079                 case IPV6_DSTOPTS:
3080                 case IPV6_RTHDRDSTOPTS:
3081                 case IPV6_RTHDR:
3082                 case IPV6_USE_MIN_MTU:
3083                 case IPV6_DONTFRAG:
3084                 case IPV6_TCLASS:
3085                 case IPV6_PREFER_TEMPADDR: /* XXX: not an rfc2292bis option */
3086                         return (ENOPROTOOPT);
3087                 }
3088         }
3089
3090         switch (optname) {
3091         case IPV6_2292PKTINFO:
3092         case IPV6_PKTINFO:
3093         {
3094                 struct ifnet *ifp = NULL;
3095                 struct in6_pktinfo *pktinfo;
3096
3097                 if (len != sizeof(struct in6_pktinfo))
3098                         return (EINVAL);
3099
3100                 pktinfo = (struct in6_pktinfo *)buf;
3101
3102                 /*
3103                  * An application can clear any sticky IPV6_PKTINFO option by
3104                  * doing a "regular" setsockopt with ipi6_addr being
3105                  * in6addr_any and ipi6_ifindex being zero.
3106                  * [RFC 3542, Section 6]
3107                  */
3108                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
3109                     pktinfo->ipi6_ifindex == 0 &&
3110                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
3111                         ip6_clearpktopts(opt, optname);
3112                         break;
3113                 }
3114
3115                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
3116                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
3117                         return (EINVAL);
3118                 }
3119
3120                 /* validate the interface index if specified. */
3121                 if (pktinfo->ipi6_ifindex > if_index ||
3122                     pktinfo->ipi6_ifindex < 0) {
3123                          return (ENXIO);
3124                 }
3125                 if (pktinfo->ipi6_ifindex) {
3126                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
3127                         if (ifp == NULL)
3128                                 return (ENXIO);
3129                 }
3130
3131                 /*
3132                  * We store the address anyway, and let in6_selectsrc()
3133                  * validate the specified address.  This is because ipi6_addr
3134                  * may not have enough information about its scope zone, and
3135                  * we may need additional information (such as outgoing
3136                  * interface or the scope zone of a destination address) to
3137                  * disambiguate the scope.
3138                  * XXX: the delay of the validation may confuse the
3139                  * application when it is used as a sticky option.
3140                  */
3141                 if (sticky) {
3142                         if (opt->ip6po_pktinfo == NULL) {
3143                                 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
3144                                     M_IP6OPT, M_WAITOK);
3145                         }
3146                         bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
3147                 } else
3148                         opt->ip6po_pktinfo = pktinfo;
3149                 break;
3150         }
3151
3152         case IPV6_2292HOPLIMIT:
3153         case IPV6_HOPLIMIT:
3154         {
3155                 int *hlimp;
3156
3157                 /*
3158                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
3159                  * to simplify the ordering among hoplimit options.
3160                  */
3161                 if (optname == IPV6_HOPLIMIT && sticky)
3162                         return (ENOPROTOOPT);
3163
3164                 if (len != sizeof(int))
3165                         return (EINVAL);
3166                 hlimp = (int *)buf;
3167                 if (*hlimp < -1 || *hlimp > 255)
3168                         return (EINVAL);
3169
3170                 opt->ip6po_hlim = *hlimp;
3171                 break;
3172         }
3173
3174         case IPV6_TCLASS:
3175         {
3176                 int tclass;
3177
3178                 if (len != sizeof(int))
3179                         return (EINVAL);
3180                 tclass = *(int *)buf;
3181                 if (tclass < -1 || tclass > 255)
3182                         return (EINVAL);
3183
3184                 opt->ip6po_tclass = tclass;
3185                 break;
3186         }
3187
3188         case IPV6_2292NEXTHOP:
3189         case IPV6_NEXTHOP:
3190                 if (!priv)
3191                         return (EPERM);
3192
3193                 if (len == 0) { /* just remove the option */
3194                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
3195                         break;
3196                 }
3197
3198                 /* check if cmsg_len is large enough for sa_len */
3199                 if (len < sizeof(struct sockaddr) || len < *buf)
3200                         return (EINVAL);
3201
3202                 switch (((struct sockaddr *)buf)->sa_family) {
3203                 case AF_INET6:
3204                 {
3205                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
3206 #if 0
3207                         int error;
3208 #endif
3209
3210                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
3211                                 return (EINVAL);
3212
3213                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
3214                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
3215                                 return (EINVAL);
3216                         }
3217 #if 0
3218                         if ((error = scope6_check_id(sa6, ip6_use_defzone))
3219                             != 0) {
3220                                 return (error);
3221                         }
3222 #endif
3223                         sa6->sin6_scope_id = 0; /* XXX */
3224                         break;
3225                 }
3226                 case AF_LINK:   /* should eventually be supported */
3227                 default:
3228                         return (EAFNOSUPPORT);
3229                 }
3230
3231                 /* turn off the previous option, then set the new option. */
3232                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
3233                 if (sticky) {
3234                         opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_WAITOK);
3235                         bcopy(buf, opt->ip6po_nexthop, *buf);
3236                 } else
3237                         opt->ip6po_nexthop = (struct sockaddr *)buf;
3238                 break;
3239
3240         case IPV6_2292HOPOPTS:
3241         case IPV6_HOPOPTS:
3242         {
3243                 struct ip6_hbh *hbh;
3244                 int hbhlen;
3245
3246                 /*
3247                  * XXX: We don't allow a non-privileged user to set ANY HbH
3248                  * options, since per-option restriction has too much
3249                  * overhead.
3250                  */
3251                 if (!priv)
3252                         return (EPERM);
3253
3254                 if (len == 0) {
3255                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
3256                         break;  /* just remove the option */
3257                 }
3258
3259                 /* message length validation */
3260                 if (len < sizeof(struct ip6_hbh))
3261                         return (EINVAL);
3262                 hbh = (struct ip6_hbh *)buf;
3263                 hbhlen = (hbh->ip6h_len + 1) << 3;
3264                 if (len != hbhlen)
3265                         return (EINVAL);
3266
3267                 /* turn off the previous option, then set the new option. */
3268                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
3269                 if (sticky) {
3270                         opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_WAITOK);
3271                         bcopy(hbh, opt->ip6po_hbh, hbhlen);
3272                 } else
3273                         opt->ip6po_hbh = hbh;
3274
3275                 break;
3276         }
3277
3278         case IPV6_2292DSTOPTS:
3279         case IPV6_DSTOPTS:
3280         case IPV6_RTHDRDSTOPTS:
3281         {
3282                 struct ip6_dest *dest, **newdest = NULL;
3283                 int destlen;
3284
3285                 if (!priv)      /* XXX: see the comment for IPV6_HOPOPTS */
3286                         return (EPERM);
3287
3288                 if (len == 0) {
3289                         ip6_clearpktopts(opt, optname);
3290                         break;  /* just remove the option */
3291                 }
3292
3293                 /* message length validation */
3294                 if (len < sizeof(struct ip6_dest))
3295                         return (EINVAL);
3296                 dest = (struct ip6_dest *)buf;
3297                 destlen = (dest->ip6d_len + 1) << 3;
3298                 if (len != destlen)
3299                         return (EINVAL);
3300
3301                 /*
3302                  * Determine the position that the destination options header
3303                  * should be inserted; before or after the routing header.
3304                  */
3305                 switch (optname) {
3306                 case IPV6_2292DSTOPTS:
3307                         /*
3308                          * The old advacned API is ambiguous on this point.
3309                          * Our approach is to determine the position based
3310                          * according to the existence of a routing header.
3311                          * Note, however, that this depends on the order of the
3312                          * extension headers in the ancillary data; the 1st
3313                          * part of the destination options header must appear
3314                          * before the routing header in the ancillary data,
3315                          * too.
3316                          * RFC2292bis solved the ambiguity by introducing
3317                          * separate ancillary data or option types.
3318                          */
3319                         if (opt->ip6po_rthdr == NULL)
3320                                 newdest = &opt->ip6po_dest1;
3321                         else
3322                                 newdest = &opt->ip6po_dest2;
3323                         break;
3324                 case IPV6_RTHDRDSTOPTS:
3325                         newdest = &opt->ip6po_dest1;
3326                         break;
3327                 case IPV6_DSTOPTS:
3328                         newdest = &opt->ip6po_dest2;
3329                         break;
3330                 }
3331
3332                 /* turn off the previous option, then set the new option. */
3333                 ip6_clearpktopts(opt, optname);
3334                 if (sticky) {
3335                         *newdest = malloc(destlen, M_IP6OPT, M_WAITOK);
3336                         bcopy(dest, *newdest, destlen);
3337                 } else
3338                         *newdest = dest;
3339
3340                 break;
3341         }
3342
3343         case IPV6_2292RTHDR:
3344         case IPV6_RTHDR:
3345         {
3346                 struct ip6_rthdr *rth;
3347                 int rthlen;
3348
3349                 if (len == 0) {
3350                         ip6_clearpktopts(opt, IPV6_RTHDR);
3351                         break;  /* just remove the option */
3352                 }
3353
3354                 /* message length validation */
3355                 if (len < sizeof(struct ip6_rthdr))
3356                         return (EINVAL);
3357                 rth = (struct ip6_rthdr *)buf;
3358                 rthlen = (rth->ip6r_len + 1) << 3;
3359                 if (len != rthlen)
3360                         return (EINVAL);
3361
3362                 switch (rth->ip6r_type) {
3363                 case IPV6_RTHDR_TYPE_0:
3364                         if (rth->ip6r_len == 0) /* must contain one addr */
3365                                 return (EINVAL);
3366                         if (rth->ip6r_len % 2) /* length must be even */
3367                                 return (EINVAL);
3368                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3369                                 return (EINVAL);
3370                         break;
3371                 default:
3372                         return (EINVAL);        /* not supported */
3373                 }
3374
3375                 /* turn off the previous option */
3376                 ip6_clearpktopts(opt, IPV6_RTHDR);
3377                 if (sticky) {
3378                         opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_WAITOK);
3379                         bcopy(rth, opt->ip6po_rthdr, rthlen);
3380                 } else
3381                         opt->ip6po_rthdr = rth;
3382
3383                 break;
3384         }
3385
3386         case IPV6_USE_MIN_MTU:
3387                 if (len != sizeof(int))
3388                         return (EINVAL);
3389                 minmtupolicy = *(int *)buf;
3390                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3391                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3392                     minmtupolicy != IP6PO_MINMTU_ALL) {
3393                         return (EINVAL);
3394                 }
3395                 opt->ip6po_minmtu = minmtupolicy;
3396                 break;
3397
3398         case IPV6_DONTFRAG:
3399                 if (len != sizeof(int))
3400                         return (EINVAL);
3401
3402                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3403                         /*
3404                          * we ignore this option for TCP sockets.
3405                          * (rfc2292bis leaves this case unspecified.)
3406                          */
3407                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3408                 } else
3409                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3410                 break;
3411
3412         case IPV6_PREFER_TEMPADDR:
3413                 if (len != sizeof(int))
3414                         return (EINVAL);
3415                 preftemp = *(int *)buf;
3416                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3417                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3418                     preftemp != IP6PO_TEMPADDR_PREFER) {
3419                         return (EINVAL);
3420                 }
3421                 opt->ip6po_prefer_tempaddr = preftemp;
3422                 break;
3423
3424         default:
3425                 return (ENOPROTOOPT);
3426         } /* end of switch */
3427
3428         return (0);
3429 }
3430
3431 /*
3432  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3433  * packet to the input queue of a specified interface.  Note that this
3434  * calls the output routine of the loopback "driver", but with an interface
3435  * pointer that might NOT be &loif -- easier than replicating that code here.
3436  */
3437 void
3438 ip6_mloopback(ifp, m, dst)
3439         struct ifnet *ifp;
3440         struct mbuf *m;
3441         struct sockaddr_in6 *dst;
3442 {
3443         struct mbuf *copym;
3444         struct ip6_hdr *ip6;
3445
3446         copym = m_copy(m, 0, M_COPYALL);
3447         if (copym == NULL)
3448                 return;
3449
3450         /*
3451          * Make sure to deep-copy IPv6 header portion in case the data
3452          * is in an mbuf cluster, so that we can safely override the IPv6
3453          * header portion later.
3454          */
3455         if ((copym->m_flags & M_EXT) != 0 ||
3456             copym->m_len < sizeof(struct ip6_hdr)) {
3457                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3458                 if (copym == NULL)
3459                         return;
3460         }
3461
3462 #ifdef DIAGNOSTIC
3463         if (copym->m_len < sizeof(*ip6)) {
3464                 m_freem(copym);
3465                 return;
3466         }
3467 #endif
3468
3469         ip6 = mtod(copym, struct ip6_hdr *);
3470         /*
3471          * clear embedded scope identifiers if necessary.
3472          * in6_clearscope will touch the addresses only when necessary.
3473          */
3474         in6_clearscope(&ip6->ip6_src);
3475         in6_clearscope(&ip6->ip6_dst);
3476
3477         (void)if_simloop(ifp, copym, dst->sin6_family, 0);
3478 }
3479
3480 /*
3481  * Chop IPv6 header off from the payload.
3482  */
3483 static int
3484 ip6_splithdr(m, exthdrs)
3485         struct mbuf *m;
3486         struct ip6_exthdrs *exthdrs;
3487 {
3488         struct mbuf *mh;
3489         struct ip6_hdr *ip6;
3490
3491         ip6 = mtod(m, struct ip6_hdr *);
3492         if (m->m_len > sizeof(*ip6)) {
3493                 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
3494                 if (mh == 0) {
3495                         m_freem(m);
3496                         return ENOBUFS;
3497                 }
3498                 M_MOVE_PKTHDR(mh, m);
3499                 MH_ALIGN(mh, sizeof(*ip6));
3500                 m->m_len -= sizeof(*ip6);
3501                 m->m_data += sizeof(*ip6);
3502                 mh->m_next = m;
3503                 m = mh;
3504                 m->m_len = sizeof(*ip6);
3505                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3506         }
3507         exthdrs->ip6e_ip6 = m;
3508         return 0;
3509 }
3510
3511 /*
3512  * Compute IPv6 extension header length.
3513  */
3514 int
3515 ip6_optlen(in6p)
3516         struct in6pcb *in6p;
3517 {
3518         int len;
3519
3520         if (!in6p->in6p_outputopts)
3521                 return 0;
3522
3523         len = 0;
3524 #define elen(x) \
3525     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3526
3527         len += elen(in6p->in6p_outputopts->ip6po_hbh);
3528         if (in6p->in6p_outputopts->ip6po_rthdr)
3529                 /* dest1 is valid with rthdr only */
3530                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
3531         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
3532         len += elen(in6p->in6p_outputopts->ip6po_dest2);
3533         return len;
3534 #undef elen
3535 }