sys/netinet6/ip6_output.c

   1 /*      $FreeBSD: src/sys/netinet6/ip6_output.c,v 1.13.2.18 2003/01/24 05:11:35 sam Exp $       */
   2 /*      $DragonFly: src/sys/netinet6/ip6_output.c,v 1.6 2003/08/07 21:17:33 dillon Exp $        */
   3 /*      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $    */
   4
   5 /*
   6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Copyright (c) 1982, 1986, 1988, 1990, 1993
  36  *      The Regents of the University of California.  All rights reserved.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 3. All advertising materials mentioning features or use of this software
  47  *    must display the following acknowledgement:
  48  *      This product includes software developed by the University of
  49  *      California, Berkeley and its contributors.
  50  * 4. Neither the name of the University nor the names of its contributors
  51  *    may be used to endorse or promote products derived from this software
  52  *    without specific prior written permission.
  53  *
  54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  64  * SUCH DAMAGE.
  65  *
  66  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  67  */
  68
  69 #include "opt_ip6fw.h"
  70 #include "opt_inet.h"
  71 #include "opt_inet6.h"
  72 #include "opt_ipsec.h"
  73
  74 #include <sys/param.h>
  75 #include <sys/malloc.h>
  76 #include <sys/mbuf.h>
  77 #include <sys/errno.h>
  78 #include <sys/protosw.h>
  79 #include <sys/socket.h>
  80 #include <sys/socketvar.h>
  81 #include <sys/systm.h>
  82 #include <sys/kernel.h>
  83 #include <sys/proc.h>
  84
  85 #include <net/if.h>
  86 #include <net/route.h>
  87
  88 #include <netinet/in.h>
  89 #include <netinet/in_var.h>
  90 #include <netinet6/in6_var.h>
  91 #include <netinet/ip6.h>
  92 #include <netinet/icmp6.h>
  93 #include <netinet6/ip6_var.h>
  94 #include <netinet/in_pcb.h>
  95 #include <netinet6/nd6.h>
  96
  97 #ifdef IPSEC
  98 #include <netinet6/ipsec.h>
  99 #ifdef INET6
 100 #include <netinet6/ipsec6.h>
 101 #endif
 102 #include <netkey/key.h>
 103 #endif /* IPSEC */
 104
 105 #ifdef FAST_IPSEC
 106 #include "ipsec.h"
 107 #include "ipsec6.h"
 108 #include <netipsec/key.h>
 109 #endif /* FAST_IPSEC */
 110
 111 #include <net/ip6fw/ip6_fw.h>
 112
 113 #include <net/net_osdep.h>
 114
 115 struct ip;
 116 extern int (*fr_checkp) __P((struct ip *, int, struct ifnet *, int, struct mbuf **));
 117
 118 static MALLOC_DEFINE(M_IPMOPTS, "ip6_moptions", "internet multicast options");
 119
 120 struct ip6_exthdrs {
 121         struct mbuf *ip6e_ip6;
 122         struct mbuf *ip6e_hbh;
 123         struct mbuf *ip6e_dest1;
 124         struct mbuf *ip6e_rthdr;
 125         struct mbuf *ip6e_dest2;
 126 };
 127
 128 static int ip6_pcbopts __P((struct ip6_pktopts **, struct mbuf *,
 129                             struct socket *, struct sockopt *sopt));
 130 static int ip6_setmoptions __P((int, struct ip6_moptions **, struct mbuf *));
 131 static int ip6_getmoptions __P((int, struct ip6_moptions *, struct mbuf **));
 132 static int ip6_copyexthdr __P((struct mbuf **, caddr_t, int));
 133 static int ip6_insertfraghdr __P((struct mbuf *, struct mbuf *, int,
 134                                   struct ip6_frag **));
 135 static int ip6_insert_jumboopt __P((struct ip6_exthdrs *, u_int32_t));
 136 static int ip6_splithdr __P((struct mbuf *, struct ip6_exthdrs *));
 137
 138 /*
 139  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 140  * header (with pri, len, nxt, hlim, src, dst).
 141  * This function may modify ver and hlim only.
 142  * The mbuf chain containing the packet will be freed.
 143  * The mbuf opt, if present, will not be freed.
 144  *
 145  * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and
 146  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 147  * which is rt_rmx.rmx_mtu.
 148  */
 149 int
 150 ip6_output(m0, opt, ro, flags, im6o, ifpp, inp)
 151         struct mbuf *m0;
 152         struct ip6_pktopts *opt;
 153         struct route_in6 *ro;
 154         int flags;
 155         struct ip6_moptions *im6o;
 156         struct ifnet **ifpp;            /* XXX: just for statistics */
 157         struct inpcb *inp;
 158 {
 159         struct ip6_hdr *ip6, *mhip6;
 160         struct ifnet *ifp, *origifp;
 161         struct mbuf *m = m0;
 162         int hlen, tlen, len, off;
 163         struct route_in6 ip6route;
 164         struct sockaddr_in6 *dst;
 165         int error = 0;
 166         struct in6_ifaddr *ia = NULL;
 167         u_long mtu;
 168         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 169         struct ip6_exthdrs exthdrs;
 170         struct in6_addr finaldst;
 171         struct route_in6 *ro_pmtu = NULL;
 172         int hdrsplit = 0;
 173         int needipsec = 0;
 174 #ifdef IPSEC
 175         int needipsectun = 0;
 176         struct secpolicy *sp = NULL;
 177         struct socket *so = inp ? inp->inp_socket : NULL;
 178
 179         ip6 = mtod(m, struct ip6_hdr *);
 180 #endif /* IPSEC */
 181 #ifdef FAST_IPSEC
 182         int needipsectun = 0;
 183         struct secpolicy *sp = NULL;
 184
 185         ip6 = mtod(m, struct ip6_hdr *);
 186 #endif /* FAST_IPSEC */
 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 (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                 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 206                 /* Routing header */
 207                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 208                 /* Destination options header(2nd part) */
 209                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 210         }
 211
 212 #ifdef IPSEC
 213         /* get a security policy for this packet */
 214         if (so == NULL)
 215                 sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
 216         else
 217                 sp = ipsec6_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
 218
 219         if (sp == NULL) {
 220                 ipsec6stat.out_inval++;
 221                 goto freehdrs;
 222         }
 223
 224         error = 0;
 225
 226         /* check policy */
 227         switch (sp->policy) {
 228         case IPSEC_POLICY_DISCARD:
 229                 /*
 230                  * This packet is just discarded.
 231                  */
 232                 ipsec6stat.out_polvio++;
 233                 goto freehdrs;
 234
 235         case IPSEC_POLICY_BYPASS:
 236         case IPSEC_POLICY_NONE:
 237                 /* no need to do IPsec. */
 238                 needipsec = 0;
 239                 break;
 240
 241         case IPSEC_POLICY_IPSEC:
 242                 if (sp->req == NULL) {
 243                         /* acquire a policy */
 244                         error = key_spdacquire(sp);
 245                         goto freehdrs;
 246                 }
 247                 needipsec = 1;
 248                 break;
 249
 250         case IPSEC_POLICY_ENTRUST:
 251         default:
 252                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
 253         }
 254 #endif /* IPSEC */
 255 #ifdef FAST_IPSEC
 256         /* get a security policy for this packet */
 257         if (inp == NULL)
 258                 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
 259         else
 260                 sp = ipsec_getpolicybysock(m, IPSEC_DIR_OUTBOUND, inp, &error);
 261
 262         if (sp == NULL) {
 263                 newipsecstat.ips_out_inval++;
 264                 goto freehdrs;
 265         }
 266
 267         error = 0;
 268
 269         /* check policy */
 270         switch (sp->policy) {
 271         case IPSEC_POLICY_DISCARD:
 272                 /*
 273                  * This packet is just discarded.
 274                  */
 275                 newipsecstat.ips_out_polvio++;
 276                 goto freehdrs;
 277
 278         case IPSEC_POLICY_BYPASS:
 279         case IPSEC_POLICY_NONE:
 280                 /* no need to do IPsec. */
 281                 needipsec = 0;
 282                 break;
 283
 284         case IPSEC_POLICY_IPSEC:
 285                 if (sp->req == NULL) {
 286                         /* acquire a policy */
 287                         error = key_spdacquire(sp);
 288                         goto freehdrs;
 289                 }
 290                 needipsec = 1;
 291                 break;
 292
 293         case IPSEC_POLICY_ENTRUST:
 294         default:
 295                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
 296         }
 297 #endif /* FAST_IPSEC */
 298
 299         /*
 300          * Calculate the total length of the extension header chain.
 301          * Keep the length of the unfragmentable part for fragmentation.
 302          */
 303         optlen = 0;
 304         if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len;
 305         if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len;
 306         if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len;
 307         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 308         /* NOTE: we don't add AH/ESP length here. do that later. */
 309         if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len;
 310
 311         /*
 312          * If we need IPsec, or there is at least one extension header,
 313          * separate IP6 header from the payload.
 314          */
 315         if ((needipsec || optlen) && !hdrsplit) {
 316                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 317                         m = NULL;
 318                         goto freehdrs;
 319                 }
 320                 m = exthdrs.ip6e_ip6;
 321                 hdrsplit++;
 322         }
 323
 324         /* adjust pointer */
 325         ip6 = mtod(m, struct ip6_hdr *);
 326
 327         /* adjust mbuf packet header length */
 328         m->m_pkthdr.len += optlen;
 329         plen = m->m_pkthdr.len - sizeof(*ip6);
 330
 331         /* If this is a jumbo payload, insert a jumbo payload option. */
 332         if (plen > IPV6_MAXPACKET) {
 333                 if (!hdrsplit) {
 334                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 335                                 m = NULL;
 336                                 goto freehdrs;
 337                         }
 338                         m = exthdrs.ip6e_ip6;
 339                         hdrsplit++;
 340                 }
 341                 /* adjust pointer */
 342                 ip6 = mtod(m, struct ip6_hdr *);
 343                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 344                         goto freehdrs;
 345                 ip6->ip6_plen = 0;
 346         } else
 347                 ip6->ip6_plen = htons(plen);
 348
 349         /*
 350          * Concatenate headers and fill in next header fields.
 351          * Here we have, on "m"
 352          *      IPv6 payload
 353          * and we insert headers accordingly.  Finally, we should be getting:
 354          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 355          *
 356          * during the header composing process, "m" points to IPv6 header.
 357          * "mprev" points to an extension header prior to esp.
 358          */
 359         {
 360                 u_char *nexthdrp = &ip6->ip6_nxt;
 361                 struct mbuf *mprev = m;
 362
 363                 /*
 364                  * we treat dest2 specially.  this makes IPsec processing
 365                  * much easier.  the goal here is to make mprev point the
 366                  * mbuf prior to dest2.
 367                  *
 368                  * result: IPv6 dest2 payload
 369                  * m and mprev will point to IPv6 header.
 370                  */
 371                 if (exthdrs.ip6e_dest2) {
 372                         if (!hdrsplit)
 373                                 panic("assumption failed: hdr not split");
 374                         exthdrs.ip6e_dest2->m_next = m->m_next;
 375                         m->m_next = exthdrs.ip6e_dest2;
 376                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 377                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 378                 }
 379
 380 #define MAKE_CHAIN(m, mp, p, i)\
 381     do {\
 382         if (m) {\
 383                 if (!hdrsplit) \
 384                         panic("assumption failed: hdr not split"); \
 385                 *mtod((m), u_char *) = *(p);\
 386                 *(p) = (i);\
 387                 p = mtod((m), u_char *);\
 388                 (m)->m_next = (mp)->m_next;\
 389                 (mp)->m_next = (m);\
 390                 (mp) = (m);\
 391         }\
 392     } while (0)
 393                 /*
 394                  * result: IPv6 hbh dest1 rthdr dest2 payload
 395                  * m will point to IPv6 header.  mprev will point to the
 396                  * extension header prior to dest2 (rthdr in the above case).
 397                  */
 398                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev,
 399                            nexthdrp, IPPROTO_HOPOPTS);
 400                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev,
 401                            nexthdrp, IPPROTO_DSTOPTS);
 402                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev,
 403                            nexthdrp, IPPROTO_ROUTING);
 404
 405 #if defined(IPSEC) || defined(FAST_IPSEC)
 406                 if (!needipsec)
 407                         goto skip_ipsec2;
 408
 409                 /*
 410                  * pointers after IPsec headers are not valid any more.
 411                  * other pointers need a great care too.
 412                  * (IPsec routines should not mangle mbufs prior to AH/ESP)
 413                  */
 414                 exthdrs.ip6e_dest2 = NULL;
 415
 416             {
 417                 struct ip6_rthdr *rh = NULL;
 418                 int segleft_org = 0;
 419                 struct ipsec_output_state state;
 420
 421                 if (exthdrs.ip6e_rthdr) {
 422                         rh = mtod(exthdrs.ip6e_rthdr, struct ip6_rthdr *);
 423                         segleft_org = rh->ip6r_segleft;
 424                         rh->ip6r_segleft = 0;
 425                 }
 426
 427                 bzero(&state, sizeof(state));
 428                 state.m = m;
 429                 error = ipsec6_output_trans(&state, nexthdrp, mprev, sp, flags,
 430                         &needipsectun);
 431                 m = state.m;
 432                 if (error) {
 433                         /* mbuf is already reclaimed in ipsec6_output_trans. */
 434                         m = NULL;
 435                         switch (error) {
 436                         case EHOSTUNREACH:
 437                         case ENETUNREACH:
 438                         case EMSGSIZE:
 439                         case ENOBUFS:
 440                         case ENOMEM:
 441                                 break;
 442                         default:
 443                                 printf("ip6_output (ipsec): error code %d\n", error);
 444                                 /* fall through */
 445                         case ENOENT:
 446                                 /* don't show these error codes to the user */
 447                                 error = 0;
 448                                 break;
 449                         }
 450                         goto bad;
 451                 }
 452                 if (exthdrs.ip6e_rthdr) {
 453                         /* ah6_output doesn't modify mbuf chain */
 454                         rh->ip6r_segleft = segleft_org;
 455                 }
 456             }
 457 skip_ipsec2:;
 458 #endif
 459         }
 460
 461         /*
 462          * If there is a routing header, replace destination address field
 463          * with the first hop of the routing header.
 464          */
 465         if (exthdrs.ip6e_rthdr) {
 466                 struct ip6_rthdr *rh =
 467                         (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr,
 468                                                   struct ip6_rthdr *));
 469                 struct ip6_rthdr0 *rh0;
 470
 471                 finaldst = ip6->ip6_dst;
 472                 switch (rh->ip6r_type) {
 473                 case IPV6_RTHDR_TYPE_0:
 474                          rh0 = (struct ip6_rthdr0 *)rh;
 475                          ip6->ip6_dst = rh0->ip6r0_addr[0];
 476                          bcopy((caddr_t)&rh0->ip6r0_addr[1],
 477                                (caddr_t)&rh0->ip6r0_addr[0],
 478                                sizeof(struct in6_addr)*(rh0->ip6r0_segleft - 1)
 479                                  );
 480                          rh0->ip6r0_addr[rh0->ip6r0_segleft - 1] = finaldst;
 481                          break;
 482                 default:        /* is it possible? */
 483                          error = EINVAL;
 484                          goto bad;
 485                 }
 486         }
 487
 488         /* Source address validation */
 489         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 490             (flags & IPV6_DADOUTPUT) == 0) {
 491                 error = EOPNOTSUPP;
 492                 ip6stat.ip6s_badscope++;
 493                 goto bad;
 494         }
 495         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 496                 error = EOPNOTSUPP;
 497                 ip6stat.ip6s_badscope++;
 498                 goto bad;
 499         }
 500
 501         ip6stat.ip6s_localout++;
 502
 503         /*
 504          * Route packet.
 505          */
 506         if (ro == 0) {
 507                 ro = &ip6route;
 508                 bzero((caddr_t)ro, sizeof(*ro));
 509         }
 510         ro_pmtu = ro;
 511         if (opt && opt->ip6po_rthdr)
 512                 ro = &opt->ip6po_route;
 513         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 514         /*
 515          * If there is a cached route,
 516          * check that it is to the same destination
 517          * and is still up. If not, free it and try again.
 518          */
 519         if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 520                          dst->sin6_family != AF_INET6 ||
 521                          !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_dst))) {
 522                 RTFREE(ro->ro_rt);
 523                 ro->ro_rt = (struct rtentry *)0;
 524         }
 525         if (ro->ro_rt == 0) {
 526                 bzero(dst, sizeof(*dst));
 527                 dst->sin6_family = AF_INET6;
 528                 dst->sin6_len = sizeof(struct sockaddr_in6);
 529                 dst->sin6_addr = ip6->ip6_dst;
 530 #ifdef SCOPEDROUTING
 531                 /* XXX: sin6_scope_id should already be fixed at this point */
 532                 if (IN6_IS_SCOPE_LINKLOCAL(&dst->sin6_addr))
 533                         dst->sin6_scope_id = ntohs(dst->sin6_addr.s6_addr16[1]);
 534 #endif
 535         }
 536 #if defined(IPSEC) || defined(FAST_IPSEC)
 537         if (needipsec && needipsectun) {
 538                 struct ipsec_output_state state;
 539
 540                 /*
 541                  * All the extension headers will become inaccessible
 542                  * (since they can be encrypted).
 543                  * Don't panic, we need no more updates to extension headers
 544                  * on inner IPv6 packet (since they are now encapsulated).
 545                  *
 546                  * IPv6 [ESP|AH] IPv6 [extension headers] payload
 547                  */
 548                 bzero(&exthdrs, sizeof(exthdrs));
 549                 exthdrs.ip6e_ip6 = m;
 550
 551                 bzero(&state, sizeof(state));
 552                 state.m = m;
 553                 state.ro = (struct route *)ro;
 554                 state.dst = (struct sockaddr *)dst;
 555
 556                 error = ipsec6_output_tunnel(&state, sp, flags);
 557
 558                 m = state.m;
 559                 ro = (struct route_in6 *)state.ro;
 560                 dst = (struct sockaddr_in6 *)state.dst;
 561                 if (error) {
 562                         /* mbuf is already reclaimed in ipsec6_output_tunnel. */
 563                         m0 = m = NULL;
 564                         m = NULL;
 565                         switch (error) {
 566                         case EHOSTUNREACH:
 567                         case ENETUNREACH:
 568                         case EMSGSIZE:
 569                         case ENOBUFS:
 570                         case ENOMEM:
 571                                 break;
 572                         default:
 573                                 printf("ip6_output (ipsec): error code %d\n", error);
 574                                 /* fall through */
 575                         case ENOENT:
 576                                 /* don't show these error codes to the user */
 577                                 error = 0;
 578                                 break;
 579                         }
 580                         goto bad;
 581                 }
 582
 583                 exthdrs.ip6e_ip6 = m;
 584         }
 585 #endif /* IPSEC */
 586
 587         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 588                 /* Unicast */
 589
 590 #define ifatoia6(ifa)   ((struct in6_ifaddr *)(ifa))
 591 #define sin6tosa(sin6)  ((struct sockaddr *)(sin6))
 592                 /* xxx
 593                  * interface selection comes here
 594                  * if an interface is specified from an upper layer,
 595                  * ifp must point it.
 596                  */
 597                 if (ro->ro_rt == 0) {
 598                         /*
 599                          * non-bsdi always clone routes, if parent is
 600                          * PRF_CLONING.
 601                          */
 602                         rtalloc((struct route *)ro);
 603                 }
 604                 if (ro->ro_rt == 0) {
 605                         ip6stat.ip6s_noroute++;
 606                         error = EHOSTUNREACH;
 607                         /* XXX in6_ifstat_inc(ifp, ifs6_out_discard); */
 608                         goto bad;
 609                 }
 610                 ia = ifatoia6(ro->ro_rt->rt_ifa);
 611                 ifp = ro->ro_rt->rt_ifp;
 612                 ro->ro_rt->rt_use++;
 613                 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
 614                         dst = (struct sockaddr_in6 *)ro->ro_rt->rt_gateway;
 615                 m->m_flags &= ~(M_BCAST | M_MCAST);     /* just in case */
 616
 617                 in6_ifstat_inc(ifp, ifs6_out_request);
 618
 619                 /*
 620                  * Check if the outgoing interface conflicts with
 621                  * the interface specified by ifi6_ifindex (if specified).
 622                  * Note that loopback interface is always okay.
 623                  * (this may happen when we are sending a packet to one of
 624                  *  our own addresses.)
 625                  */
 626                 if (opt && opt->ip6po_pktinfo
 627                  && opt->ip6po_pktinfo->ipi6_ifindex) {
 628                         if (!(ifp->if_flags & IFF_LOOPBACK)
 629                          && ifp->if_index != opt->ip6po_pktinfo->ipi6_ifindex) {
 630                                 ip6stat.ip6s_noroute++;
 631                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 632                                 error = EHOSTUNREACH;
 633                                 goto bad;
 634                         }
 635                 }
 636
 637                 if (opt && opt->ip6po_hlim != -1)
 638                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 639         } else {
 640                 /* Multicast */
 641                 struct  in6_multi *in6m;
 642
 643                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 644
 645                 /*
 646                  * See if the caller provided any multicast options
 647                  */
 648                 ifp = NULL;
 649                 if (im6o != NULL) {
 650                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 651                         if (im6o->im6o_multicast_ifp != NULL)
 652                                 ifp = im6o->im6o_multicast_ifp;
 653                 } else
 654                         ip6->ip6_hlim = ip6_defmcasthlim;
 655
 656                 /*
 657                  * See if the caller provided the outgoing interface
 658                  * as an ancillary data.
 659                  * Boundary check for ifindex is assumed to be already done.
 660                  */
 661                 if (opt && opt->ip6po_pktinfo && opt->ip6po_pktinfo->ipi6_ifindex)
 662                         ifp = ifindex2ifnet[opt->ip6po_pktinfo->ipi6_ifindex];
 663
 664                 /*
 665                  * If the destination is a node-local scope multicast,
 666                  * the packet should be loop-backed only.
 667                  */
 668                 if (IN6_IS_ADDR_MC_NODELOCAL(&ip6->ip6_dst)) {
 669                         /*
 670                          * If the outgoing interface is already specified,
 671                          * it should be a loopback interface.
 672                          */
 673                         if (ifp && (ifp->if_flags & IFF_LOOPBACK) == 0) {
 674                                 ip6stat.ip6s_badscope++;
 675                                 error = ENETUNREACH; /* XXX: better error? */
 676                                 /* XXX correct ifp? */
 677                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 678                                 goto bad;
 679                         } else {
 680                                 ifp = &loif[0];
 681                         }
 682                 }
 683
 684                 if (opt && opt->ip6po_hlim != -1)
 685                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 686
 687                 /*
 688                  * If caller did not provide an interface lookup a
 689                  * default in the routing table.  This is either a
 690                  * default for the speicfied group (i.e. a host
 691                  * route), or a multicast default (a route for the
 692                  * ``net'' ff00::/8).
 693                  */
 694                 if (ifp == NULL) {
 695                         if (ro->ro_rt == 0) {
 696                                 ro->ro_rt = rtalloc1((struct sockaddr *)
 697                                                 &ro->ro_dst, 0, 0UL);
 698                         }
 699                         if (ro->ro_rt == 0) {
 700                                 ip6stat.ip6s_noroute++;
 701                                 error = EHOSTUNREACH;
 702                                 /* XXX in6_ifstat_inc(ifp, ifs6_out_discard) */
 703                                 goto bad;
 704                         }
 705                         ia = ifatoia6(ro->ro_rt->rt_ifa);
 706                         ifp = ro->ro_rt->rt_ifp;
 707                         ro->ro_rt->rt_use++;
 708                 }
 709
 710                 if ((flags & IPV6_FORWARDING) == 0)
 711                         in6_ifstat_inc(ifp, ifs6_out_request);
 712                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 713
 714                 /*
 715                  * Confirm that the outgoing interface supports multicast.
 716                  */
 717                 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 718                         ip6stat.ip6s_noroute++;
 719                         in6_ifstat_inc(ifp, ifs6_out_discard);
 720                         error = ENETUNREACH;
 721                         goto bad;
 722                 }
 723                 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
 724                 if (in6m != NULL &&
 725                    (im6o == NULL || im6o->im6o_multicast_loop)) {
 726                         /*
 727                          * If we belong to the destination multicast group
 728                          * on the outgoing interface, and the caller did not
 729                          * forbid loopback, loop back a copy.
 730                          */
 731                         ip6_mloopback(ifp, m, dst);
 732                 } else {
 733                         /*
 734                          * If we are acting as a multicast router, perform
 735                          * multicast forwarding as if the packet had just
 736                          * arrived on the interface to which we are about
 737                          * to send.  The multicast forwarding function
 738                          * recursively calls this function, using the
 739                          * IPV6_FORWARDING flag to prevent infinite recursion.
 740                          *
 741                          * Multicasts that are looped back by ip6_mloopback(),
 742                          * above, will be forwarded by the ip6_input() routine,
 743                          * if necessary.
 744                          */
 745                         if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 746                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 747                                         m_freem(m);
 748                                         goto done;
 749                                 }
 750                         }
 751                 }
 752                 /*
 753                  * Multicasts with a hoplimit of zero may be looped back,
 754                  * above, but must not be transmitted on a network.
 755                  * Also, multicasts addressed to the loopback interface
 756                  * are not sent -- the above call to ip6_mloopback() will
 757                  * loop back a copy if this host actually belongs to the
 758                  * destination group on the loopback interface.
 759                  */
 760                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK)) {
 761                         m_freem(m);
 762                         goto done;
 763                 }
 764         }
 765
 766         /*
 767          * Fill the outgoing inteface to tell the upper layer
 768          * to increment per-interface statistics.
 769          */
 770         if (ifpp)
 771                 *ifpp = ifp;
 772
 773         /*
 774          * Determine path MTU.
 775          */
 776         if (ro_pmtu != ro) {
 777                 /* The first hop and the final destination may differ. */
 778                 struct sockaddr_in6 *sin6_fin =
 779                         (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
 780                 if (ro_pmtu->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 781                                        !IN6_ARE_ADDR_EQUAL(&sin6_fin->sin6_addr,
 782                                                            &finaldst))) {
 783                         RTFREE(ro_pmtu->ro_rt);
 784                         ro_pmtu->ro_rt = (struct rtentry *)0;
 785                 }
 786                 if (ro_pmtu->ro_rt == 0) {
 787                         bzero(sin6_fin, sizeof(*sin6_fin));
 788                         sin6_fin->sin6_family = AF_INET6;
 789                         sin6_fin->sin6_len = sizeof(struct sockaddr_in6);
 790                         sin6_fin->sin6_addr = finaldst;
 791
 792                         rtalloc((struct route *)ro_pmtu);
 793                 }
 794         }
 795         if (ro_pmtu->ro_rt != NULL) {
 796                 u_int32_t ifmtu = nd_ifinfo[ifp->if_index].linkmtu;
 797
 798                 mtu = ro_pmtu->ro_rt->rt_rmx.rmx_mtu;
 799                 if (mtu > ifmtu || mtu == 0) {
 800                         /*
 801                          * The MTU on the route is larger than the MTU on
 802                          * the interface!  This shouldn't happen, unless the
 803                          * MTU of the interface has been changed after the
 804                          * interface was brought up.  Change the MTU in the
 805                          * route to match the interface MTU (as long as the
 806                          * field isn't locked).
 807                          *
 808                          * if MTU on the route is 0, we need to fix the MTU.
 809                          * this case happens with path MTU discovery timeouts.
 810                          */
 811                          mtu = ifmtu;
 812                          if ((ro_pmtu->ro_rt->rt_rmx.rmx_locks & RTV_MTU) == 0)
 813                                  ro_pmtu->ro_rt->rt_rmx.rmx_mtu = mtu; /* XXX */
 814                 }
 815         } else {
 816                 mtu = nd_ifinfo[ifp->if_index].linkmtu;
 817         }
 818
 819         /*
 820          * advanced API (IPV6_USE_MIN_MTU) overrides mtu setting
 821          */
 822         if ((flags & IPV6_MINMTU) != 0 && mtu > IPV6_MMTU)
 823                 mtu = IPV6_MMTU;
 824
 825         /* Fake scoped addresses */
 826         if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
 827                 /*
 828                  * If source or destination address is a scoped address, and
 829                  * the packet is going to be sent to a loopback interface,
 830                  * we should keep the original interface.
 831                  */
 832
 833                 /*
 834                  * XXX: this is a very experimental and temporary solution.
 835                  * We eventually have sockaddr_in6 and use the sin6_scope_id
 836                  * field of the structure here.
 837                  * We rely on the consistency between two scope zone ids
 838                  * of source and destination, which should already be assured.
 839                  * Larger scopes than link will be supported in the future.
 840                  */
 841                 origifp = NULL;
 842                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
 843                         origifp = ifindex2ifnet[ntohs(ip6->ip6_src.s6_addr16[1])];
 844                 else if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
 845                         origifp = ifindex2ifnet[ntohs(ip6->ip6_dst.s6_addr16[1])];
 846                 /*
 847                  * XXX: origifp can be NULL even in those two cases above.
 848                  * For example, if we remove the (only) link-local address
 849                  * from the loopback interface, and try to send a link-local
 850                  * address without link-id information.  Then the source
 851                  * address is ::1, and the destination address is the
 852                  * link-local address with its s6_addr16[1] being zero.
 853                  * What is worse, if the packet goes to the loopback interface
 854                  * by a default rejected route, the null pointer would be
 855                  * passed to looutput, and the kernel would hang.
 856                  * The following last resort would prevent such disaster.
 857                  */
 858                 if (origifp == NULL)
 859                         origifp = ifp;
 860         }
 861         else
 862                 origifp = ifp;
 863 #ifndef SCOPEDROUTING
 864         /*
 865          * clear embedded scope identifiers if necessary.
 866          * in6_clearscope will touch the addresses only when necessary.
 867          */
 868         in6_clearscope(&ip6->ip6_src);
 869         in6_clearscope(&ip6->ip6_dst);
 870 #endif
 871
 872         /*
 873          * Check with the firewall...
 874          */
 875         if (ip6_fw_enable && ip6_fw_chk_ptr) {
 876                 u_short port = 0;
 877                 m->m_pkthdr.rcvif = NULL;       /* XXX */
 878                 /* If ipfw says divert, we have to just drop packet */
 879                 if ((*ip6_fw_chk_ptr)(&ip6, ifp, &port, &m)) {
 880                         m_freem(m);
 881                         goto done;
 882                 }
 883                 if (!m) {
 884                         error = EACCES;
 885                         goto done;
 886                 }
 887         }
 888
 889         /*
 890          * If the outgoing packet contains a hop-by-hop options header,
 891          * it must be examined and processed even by the source node.
 892          * (RFC 2460, section 4.)
 893          */
 894         if (exthdrs.ip6e_hbh) {
 895                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 896                 u_int32_t dummy1; /* XXX unused */
 897                 u_int32_t dummy2; /* XXX unused */
 898
 899 #ifdef DIAGNOSTIC
 900                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 901                         panic("ip6e_hbh is not continuous");
 902 #endif
 903                 /*
 904                  *  XXX: if we have to send an ICMPv6 error to the sender,
 905                  *       we need the M_LOOP flag since icmp6_error() expects
 906                  *       the IPv6 and the hop-by-hop options header are
 907                  *       continuous unless the flag is set.
 908                  */
 909                 m->m_flags |= M_LOOP;
 910                 m->m_pkthdr.rcvif = ifp;
 911                 if (ip6_process_hopopts(m,
 912                                         (u_int8_t *)(hbh + 1),
 913                                         ((hbh->ip6h_len + 1) << 3) -
 914                                         sizeof(struct ip6_hbh),
 915                                         &dummy1, &dummy2) < 0) {
 916                         /* m was already freed at this point */
 917                         error = EINVAL;/* better error? */
 918                         goto done;
 919                 }
 920                 m->m_flags &= ~M_LOOP; /* XXX */
 921                 m->m_pkthdr.rcvif = NULL;
 922         }
 923
 924         /*
 925          * Check if we want to allow this packet to be processed.
 926          * Consider it to be bad if not.
 927          */
 928         if (fr_checkp) {
 929                 struct  mbuf    *m1 = m;
 930
 931                 if ((*fr_checkp)((struct ip *)ip6, sizeof(*ip6), ifp, 1, &m1))
 932                         goto done;
 933                 m = m1;
 934                 if (m == NULL)
 935                         goto done;
 936                 ip6 = mtod(m, struct ip6_hdr *);
 937         }
 938
 939         /*
 940          * Send the packet to the outgoing interface.
 941          * If necessary, do IPv6 fragmentation before sending.
 942          */
 943         tlen = m->m_pkthdr.len;
 944         if (tlen <= mtu
 945 #ifdef notyet
 946             /*
 947              * On any link that cannot convey a 1280-octet packet in one piece,
 948              * link-specific fragmentation and reassembly must be provided at
 949              * a layer below IPv6. [RFC 2460, sec.5]
 950              * Thus if the interface has ability of link-level fragmentation,
 951              * we can just send the packet even if the packet size is
 952              * larger than the link's MTU.
 953              * XXX: IFF_FRAGMENTABLE (or such) flag has not been defined yet...
 954              */
 955
 956             || ifp->if_flags & IFF_FRAGMENTABLE
 957 #endif
 958             )
 959         {
 960                 /* Record statistics for this interface address. */
 961                 if (ia && !(flags & IPV6_FORWARDING)) {
 962                         ia->ia_ifa.if_opackets++;
 963                         ia->ia_ifa.if_obytes += m->m_pkthdr.len;
 964                 }
 965 #ifdef IPSEC
 966                 /* clean ipsec history once it goes out of the node */
 967                 ipsec_delaux(m);
 968 #endif
 969                 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
 970                 goto done;
 971         } else if (mtu < IPV6_MMTU) {
 972                 /*
 973                  * note that path MTU is never less than IPV6_MMTU
 974                  * (see icmp6_input).
 975                  */
 976                 error = EMSGSIZE;
 977                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 978                 goto bad;
 979         } else if (ip6->ip6_plen == 0) { /* jumbo payload cannot be fragmented */
 980                 error = EMSGSIZE;
 981                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 982                 goto bad;
 983         } else {
 984                 struct mbuf **mnext, *m_frgpart;
 985                 struct ip6_frag *ip6f;
 986                 u_int32_t id = htonl(ip6_id++);
 987                 u_char nextproto;
 988
 989                 /*
 990                  * Too large for the destination or interface;
 991                  * fragment if possible.
 992                  * Must be able to put at least 8 bytes per fragment.
 993                  */
 994                 hlen = unfragpartlen;
 995                 if (mtu > IPV6_MAXPACKET)
 996                         mtu = IPV6_MAXPACKET;
 997
 998                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
 999                 if (len < 8) {
1000                         error = EMSGSIZE;
1001                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1002                         goto bad;
1003                 }
1004
1005                 mnext = &m->m_nextpkt;
1006
1007                 /*
1008                  * Change the next header field of the last header in the
1009                  * unfragmentable part.
1010                  */
1011                 if (exthdrs.ip6e_rthdr) {
1012                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1013                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1014                 } else if (exthdrs.ip6e_dest1) {
1015                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1016                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1017                 } else if (exthdrs.ip6e_hbh) {
1018                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1019                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1020                 } else {
1021                         nextproto = ip6->ip6_nxt;
1022                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1023                 }
1024
1025                 /*
1026                  * Loop through length of segment after first fragment,
1027                  * make new header and copy data of each part and link onto
1028                  * chain.
1029                  */
1030                 m0 = m;
1031                 for (off = hlen; off < tlen; off += len) {
1032                         MGETHDR(m, M_DONTWAIT, MT_HEADER);
1033                         if (!m) {
1034                                 error = ENOBUFS;
1035                                 ip6stat.ip6s_odropped++;
1036                                 goto sendorfree;
1037                         }
1038                         m->m_pkthdr.rcvif = NULL;
1039                         m->m_flags = m0->m_flags & M_COPYFLAGS;
1040                         *mnext = m;
1041                         mnext = &m->m_nextpkt;
1042                         m->m_data += max_linkhdr;
1043                         mhip6 = mtod(m, struct ip6_hdr *);
1044                         *mhip6 = *ip6;
1045                         m->m_len = sizeof(*mhip6);
1046                         error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
1047                         if (error) {
1048                                 ip6stat.ip6s_odropped++;
1049                                 goto sendorfree;
1050                         }
1051                         ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
1052                         if (off + len >= tlen)
1053                                 len = tlen - off;
1054                         else
1055                                 ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
1056                         mhip6->ip6_plen = htons((u_short)(len + hlen +
1057                                                           sizeof(*ip6f) -
1058                                                           sizeof(struct ip6_hdr)));
1059                         if ((m_frgpart = m_copy(m0, off, len)) == 0) {
1060                                 error = ENOBUFS;
1061                                 ip6stat.ip6s_odropped++;
1062                                 goto sendorfree;
1063                         }
1064                         m_cat(m, m_frgpart);
1065                         m->m_pkthdr.len = len + hlen + sizeof(*ip6f);
1066                         m->m_pkthdr.rcvif = (struct ifnet *)0;
1067                         ip6f->ip6f_reserved = 0;
1068                         ip6f->ip6f_ident = id;
1069                         ip6f->ip6f_nxt = nextproto;
1070                         ip6stat.ip6s_ofragments++;
1071                         in6_ifstat_inc(ifp, ifs6_out_fragcreat);
1072                 }
1073
1074                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1075         }
1076
1077         /*
1078          * Remove leading garbages.
1079          */
1080 sendorfree:
1081         m = m0->m_nextpkt;
1082         m0->m_nextpkt = 0;
1083         m_freem(m0);
1084         for (m0 = m; m; m = m0) {
1085                 m0 = m->m_nextpkt;
1086                 m->m_nextpkt = 0;
1087                 if (error == 0) {
1088                         /* Record statistics for this interface address. */
1089                         if (ia) {
1090                                 ia->ia_ifa.if_opackets++;
1091                                 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1092                         }
1093 #ifdef IPSEC
1094                         /* clean ipsec history once it goes out of the node */
1095                         ipsec_delaux(m);
1096 #endif
1097                         error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
1098                 } else
1099                         m_freem(m);
1100         }
1101
1102         if (error == 0)
1103                 ip6stat.ip6s_fragmented++;
1104
1105 done:
1106         if (ro == &ip6route && ro->ro_rt) { /* brace necessary for RTFREE */
1107                 RTFREE(ro->ro_rt);
1108         } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) {
1109                 RTFREE(ro_pmtu->ro_rt);
1110         }
1111
1112 #ifdef IPSEC
1113         if (sp != NULL)
1114                 key_freesp(sp);
1115 #endif /* IPSEC */
1116 #ifdef FAST_IPSEC
1117         if (sp != NULL)
1118                 KEY_FREESP(&sp);
1119 #endif /* FAST_IPSEC */
1120
1121         return(error);
1122
1123 freehdrs:
1124         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1125         m_freem(exthdrs.ip6e_dest1);
1126         m_freem(exthdrs.ip6e_rthdr);
1127         m_freem(exthdrs.ip6e_dest2);
1128         /* fall through */
1129 bad:
1130         m_freem(m);
1131         goto done;
1132 }
1133
1134 static int
1135 ip6_copyexthdr(mp, hdr, hlen)
1136         struct mbuf **mp;
1137         caddr_t hdr;
1138         int hlen;
1139 {
1140         struct mbuf *m;
1141
1142         if (hlen > MCLBYTES)
1143                 return(ENOBUFS); /* XXX */
1144
1145         MGET(m, M_DONTWAIT, MT_DATA);
1146         if (!m)
1147                 return(ENOBUFS);
1148
1149         if (hlen > MLEN) {
1150                 MCLGET(m, M_DONTWAIT);
1151                 if ((m->m_flags & M_EXT) == 0) {
1152                         m_free(m);
1153                         return(ENOBUFS);
1154                 }
1155         }
1156         m->m_len = hlen;
1157         if (hdr)
1158                 bcopy(hdr, mtod(m, caddr_t), hlen);
1159
1160         *mp = m;
1161         return(0);
1162 }
1163
1164 /*
1165  * Insert jumbo payload option.
1166  */
1167 static int
1168 ip6_insert_jumboopt(exthdrs, plen)
1169         struct ip6_exthdrs *exthdrs;
1170         u_int32_t plen;
1171 {
1172         struct mbuf *mopt;
1173         u_char *optbuf;
1174         u_int32_t v;
1175
1176 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1177
1178         /*
1179          * If there is no hop-by-hop options header, allocate new one.
1180          * If there is one but it doesn't have enough space to store the
1181          * jumbo payload option, allocate a cluster to store the whole options.
1182          * Otherwise, use it to store the options.
1183          */
1184         if (exthdrs->ip6e_hbh == 0) {
1185                 MGET(mopt, M_DONTWAIT, MT_DATA);
1186                 if (mopt == 0)
1187                         return(ENOBUFS);
1188                 mopt->m_len = JUMBOOPTLEN;
1189                 optbuf = mtod(mopt, u_char *);
1190                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1191                 exthdrs->ip6e_hbh = mopt;
1192         } else {
1193                 struct ip6_hbh *hbh;
1194
1195                 mopt = exthdrs->ip6e_hbh;
1196                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1197                         /*
1198                          * XXX assumption:
1199                          * - exthdrs->ip6e_hbh is not referenced from places
1200                          *   other than exthdrs.
1201                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1202                          */
1203                         int oldoptlen = mopt->m_len;
1204                         struct mbuf *n;
1205
1206                         /*
1207                          * XXX: give up if the whole (new) hbh header does
1208                          * not fit even in an mbuf cluster.
1209                          */
1210                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1211                                 return(ENOBUFS);
1212
1213                         /*
1214                          * As a consequence, we must always prepare a cluster
1215                          * at this point.
1216                          */
1217                         MGET(n, M_DONTWAIT, MT_DATA);
1218                         if (n) {
1219                                 MCLGET(n, M_DONTWAIT);
1220                                 if ((n->m_flags & M_EXT) == 0) {
1221                                         m_freem(n);
1222                                         n = NULL;
1223                                 }
1224                         }
1225                         if (!n)
1226                                 return(ENOBUFS);
1227                         n->m_len = oldoptlen + JUMBOOPTLEN;
1228                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1229                               oldoptlen);
1230                         optbuf = mtod(n, caddr_t) + oldoptlen;
1231                         m_freem(mopt);
1232                         mopt = exthdrs->ip6e_hbh = n;
1233                 } else {
1234                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1235                         mopt->m_len += JUMBOOPTLEN;
1236                 }
1237                 optbuf[0] = IP6OPT_PADN;
1238                 optbuf[1] = 1;
1239
1240                 /*
1241                  * Adjust the header length according to the pad and
1242                  * the jumbo payload option.
1243                  */
1244                 hbh = mtod(mopt, struct ip6_hbh *);
1245                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1246         }
1247
1248         /* fill in the option. */
1249         optbuf[2] = IP6OPT_JUMBO;
1250         optbuf[3] = 4;
1251         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1252         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1253
1254         /* finally, adjust the packet header length */
1255         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1256
1257         return(0);
1258 #undef JUMBOOPTLEN
1259 }
1260
1261 /*
1262  * Insert fragment header and copy unfragmentable header portions.
1263  */
1264 static int
1265 ip6_insertfraghdr(m0, m, hlen, frghdrp)
1266         struct mbuf *m0, *m;
1267         int hlen;
1268         struct ip6_frag **frghdrp;
1269 {
1270         struct mbuf *n, *mlast;
1271
1272         if (hlen > sizeof(struct ip6_hdr)) {
1273                 n = m_copym(m0, sizeof(struct ip6_hdr),
1274                             hlen - sizeof(struct ip6_hdr), M_DONTWAIT);
1275                 if (n == 0)
1276                         return(ENOBUFS);
1277                 m->m_next = n;
1278         } else
1279                 n = m;
1280
1281         /* Search for the last mbuf of unfragmentable part. */
1282         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1283                 ;
1284
1285         if ((mlast->m_flags & M_EXT) == 0 &&
1286             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1287                 /* use the trailing space of the last mbuf for the fragment hdr */
1288                 *frghdrp =
1289                         (struct ip6_frag *)(mtod(mlast, caddr_t) + mlast->m_len);
1290                 mlast->m_len += sizeof(struct ip6_frag);
1291                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1292         } else {
1293                 /* allocate a new mbuf for the fragment header */
1294                 struct mbuf *mfrg;
1295
1296                 MGET(mfrg, M_DONTWAIT, MT_DATA);
1297                 if (mfrg == 0)
1298                         return(ENOBUFS);
1299                 mfrg->m_len = sizeof(struct ip6_frag);
1300                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1301                 mlast->m_next = mfrg;
1302         }
1303
1304         return(0);
1305 }
1306
1307 /*
1308  * IP6 socket option processing.
1309  */
1310 int
1311 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1312 {
1313         int privileged;
1314         struct inpcb *in6p = sotoinpcb(so);
1315         int error, optval;
1316         int level, op, optname;
1317         int optlen;
1318         struct thread *td;
1319
1320         if (sopt) {
1321                 level = sopt->sopt_level;
1322                 op = sopt->sopt_dir;
1323                 optname = sopt->sopt_name;
1324                 optlen = sopt->sopt_valsize;
1325                 td = sopt->sopt_td;
1326         } else {
1327                 panic("ip6_ctloutput: arg soopt is NULL");
1328                 /* NOT REACHED */
1329                 td = NULL;
1330         }
1331         error = optval = 0;
1332
1333         privileged = (td == NULL || suser(td)) ? 0 : 1;
1334
1335         if (level == IPPROTO_IPV6) {
1336                 switch (op) {
1337
1338                 case SOPT_SET:
1339                         switch (optname) {
1340                         case IPV6_PKTOPTIONS:
1341                         {
1342                                 struct mbuf *m;
1343
1344                                 error = soopt_getm(sopt, &m); /* XXX */
1345                                 if (error != NULL)
1346                                         break;
1347                                 error = soopt_mcopyin(sopt, m); /* XXX */
1348                                 if (error != NULL)
1349                                         break;
1350                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1351                                                     m, so, sopt);
1352                                 m_freem(m); /* XXX */
1353                                 break;
1354                         }
1355
1356                         /*
1357                          * Use of some Hop-by-Hop options or some
1358                          * Destination options, might require special
1359                          * privilege.  That is, normal applications
1360                          * (without special privilege) might be forbidden
1361                          * from setting certain options in outgoing packets,
1362                          * and might never see certain options in received
1363                          * packets. [RFC 2292 Section 6]
1364                          * KAME specific note:
1365                          *  KAME prevents non-privileged users from sending or
1366                          *  receiving ANY hbh/dst options in order to avoid
1367                          *  overhead of parsing options in the kernel.
1368                          */
1369                         case IPV6_UNICAST_HOPS:
1370                         case IPV6_CHECKSUM:
1371                         case IPV6_FAITH:
1372
1373                         case IPV6_V6ONLY:
1374                                 if (optlen != sizeof(int)) {
1375                                         error = EINVAL;
1376                                         break;
1377                                 }
1378                                 error = sooptcopyin(sopt, &optval,
1379                                         sizeof optval, sizeof optval);
1380                                 if (error)
1381                                         break;
1382                                 switch (optname) {
1383
1384                                 case IPV6_UNICAST_HOPS:
1385                                         if (optval < -1 || optval >= 256)
1386                                                 error = EINVAL;
1387                                         else {
1388                                                 /* -1 = kernel default */
1389                                                 in6p->in6p_hops = optval;
1390
1391                                                 if ((in6p->in6p_vflag &
1392                                                      INP_IPV4) != 0)
1393                                                         in6p->inp_ip_ttl = optval;
1394                                         }
1395                                         break;
1396 #define OPTSET(bit) \
1397 do { \
1398         if (optval) \
1399                 in6p->in6p_flags |= (bit); \
1400         else \
1401                 in6p->in6p_flags &= ~(bit); \
1402 } while (0)
1403 #define OPTBIT(bit) (in6p->in6p_flags & (bit) ? 1 : 0)
1404
1405                                 case IPV6_CHECKSUM:
1406                                         in6p->in6p_cksum = optval;
1407                                         break;
1408
1409                                 case IPV6_FAITH:
1410                                         OPTSET(IN6P_FAITH);
1411                                         break;
1412
1413                                 case IPV6_V6ONLY:
1414                                         /*
1415                                          * make setsockopt(IPV6_V6ONLY)
1416                                          * available only prior to bind(2).
1417                                          * see ipng mailing list, Jun 22 2001.
1418                                          */
1419                                         if (in6p->in6p_lport ||
1420                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr))
1421                                         {
1422                                                 error = EINVAL;
1423                                                 break;
1424                                         }
1425                                         OPTSET(IN6P_IPV6_V6ONLY);
1426                                         if (optval)
1427                                                 in6p->in6p_vflag &= ~INP_IPV4;
1428                                         else
1429                                                 in6p->in6p_vflag |= INP_IPV4;
1430                                         break;
1431                                 }
1432                                 break;
1433
1434                         case IPV6_PKTINFO:
1435                         case IPV6_HOPLIMIT:
1436                         case IPV6_HOPOPTS:
1437                         case IPV6_DSTOPTS:
1438                         case IPV6_RTHDR:
1439                                 /* RFC 2292 */
1440                                 if (optlen != sizeof(int)) {
1441                                         error = EINVAL;
1442                                         break;
1443                                 }
1444                                 error = sooptcopyin(sopt, &optval,
1445                                         sizeof optval, sizeof optval);
1446                                 if (error)
1447                                         break;
1448                                 switch (optname) {
1449                                 case IPV6_PKTINFO:
1450                                         OPTSET(IN6P_PKTINFO);
1451                                         break;
1452                                 case IPV6_HOPLIMIT:
1453                                         OPTSET(IN6P_HOPLIMIT);
1454                                         break;
1455                                 case IPV6_HOPOPTS:
1456                                         /*
1457                                          * Check super-user privilege.
1458                                          * See comments for IPV6_RECVHOPOPTS.
1459                                          */
1460                                         if (!privileged)
1461                                                 return(EPERM);
1462                                         OPTSET(IN6P_HOPOPTS);
1463                                         break;
1464                                 case IPV6_DSTOPTS:
1465                                         if (!privileged)
1466                                                 return(EPERM);
1467                                         OPTSET(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1468                                         break;
1469                                 case IPV6_RTHDR:
1470                                         OPTSET(IN6P_RTHDR);
1471                                         break;
1472                                 }
1473                                 break;
1474 #undef OPTSET
1475
1476                         case IPV6_MULTICAST_IF:
1477                         case IPV6_MULTICAST_HOPS:
1478                         case IPV6_MULTICAST_LOOP:
1479                         case IPV6_JOIN_GROUP:
1480                         case IPV6_LEAVE_GROUP:
1481                             {
1482                                 struct mbuf *m;
1483                                 if (sopt->sopt_valsize > MLEN) {
1484                                         error = EMSGSIZE;
1485                                         break;
1486                                 }
1487                                 /* XXX */
1488                                 MGET(m, sopt->sopt_td ? M_WAIT : M_DONTWAIT, MT_HEADER);
1489                                 if (m == 0) {
1490                                         error = ENOBUFS;
1491                                         break;
1492                                 }
1493                                 m->m_len = sopt->sopt_valsize;
1494                                 error = sooptcopyin(sopt, mtod(m, char *),
1495                                                     m->m_len, m->m_len);
1496                                 error = ip6_setmoptions(sopt->sopt_name,
1497                                                         &in6p->in6p_moptions,
1498                                                         m);
1499                                 (void)m_free(m);
1500                             }
1501                                 break;
1502
1503                         case IPV6_PORTRANGE:
1504                                 error = sooptcopyin(sopt, &optval,
1505                                     sizeof optval, sizeof optval);
1506                                 if (error)
1507                                         break;
1508
1509                                 switch (optval) {
1510                                 case IPV6_PORTRANGE_DEFAULT:
1511                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1512                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1513                                         break;
1514
1515                                 case IPV6_PORTRANGE_HIGH:
1516                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1517                                         in6p->in6p_flags |= IN6P_HIGHPORT;
1518                                         break;
1519
1520                                 case IPV6_PORTRANGE_LOW:
1521                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1522                                         in6p->in6p_flags |= IN6P_LOWPORT;
1523                                         break;
1524
1525                                 default:
1526                                         error = EINVAL;
1527                                         break;
1528                                 }
1529                                 break;
1530
1531 #if defined(IPSEC) || defined(FAST_IPSEC)
1532                         case IPV6_IPSEC_POLICY:
1533                             {
1534                                 caddr_t req = NULL;
1535                                 size_t len = 0;
1536                                 struct mbuf *m;
1537
1538                                 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1539                                         break;
1540                                 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1541                                         break;
1542                                 if (m) {
1543                                         req = mtod(m, caddr_t);
1544                                         len = m->m_len;
1545                                 }
1546                                 error = ipsec6_set_policy(in6p, optname, req,
1547                                                           len, privileged);
1548                                 m_freem(m);
1549                             }
1550                                 break;
1551 #endif /* KAME IPSEC */
1552
1553                         case IPV6_FW_ADD:
1554                         case IPV6_FW_DEL:
1555                         case IPV6_FW_FLUSH:
1556                         case IPV6_FW_ZERO:
1557                             {
1558                                 struct mbuf *m;
1559                                 struct mbuf **mp = &m;
1560
1561                                 if (ip6_fw_ctl_ptr == NULL)
1562                                         return EINVAL;
1563                                 /* XXX */
1564                                 if ((error = soopt_getm(sopt, &m)) != 0)
1565                                         break;
1566                                 /* XXX */
1567                                 if ((error = soopt_mcopyin(sopt, m)) != 0)
1568                                         break;
1569                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
1570                                 m = *mp;
1571                             }
1572                                 break;
1573
1574                         default:
1575                                 error = ENOPROTOOPT;
1576                                 break;
1577                         }
1578                         break;
1579
1580                 case SOPT_GET:
1581                         switch (optname) {
1582
1583                         case IPV6_PKTOPTIONS:
1584                                 if (in6p->in6p_options) {
1585                                         struct mbuf *m;
1586                                         m = m_copym(in6p->in6p_options,
1587                                             0, M_COPYALL, M_WAIT);
1588                                         error = soopt_mcopyout(sopt, m);
1589                                         if (error == 0)
1590                                                 m_freem(m);
1591                                 } else
1592                                         sopt->sopt_valsize = 0;
1593                                 break;
1594
1595                         case IPV6_UNICAST_HOPS:
1596                         case IPV6_CHECKSUM:
1597
1598                         case IPV6_FAITH:
1599                         case IPV6_V6ONLY:
1600                         case IPV6_PORTRANGE:
1601                                 switch (optname) {
1602
1603                                 case IPV6_UNICAST_HOPS:
1604                                         optval = in6p->in6p_hops;
1605                                         break;
1606
1607                                 case IPV6_CHECKSUM:
1608                                         optval = in6p->in6p_cksum;
1609                                         break;
1610
1611                                 case IPV6_FAITH:
1612                                         optval = OPTBIT(IN6P_FAITH);
1613                                         break;
1614
1615                                 case IPV6_V6ONLY:
1616                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
1617                                         break;
1618
1619                                 case IPV6_PORTRANGE:
1620                                     {
1621                                         int flags;
1622                                         flags = in6p->in6p_flags;
1623                                         if (flags & IN6P_HIGHPORT)
1624                                                 optval = IPV6_PORTRANGE_HIGH;
1625                                         else if (flags & IN6P_LOWPORT)
1626                                                 optval = IPV6_PORTRANGE_LOW;
1627                                         else
1628                                                 optval = 0;
1629                                         break;
1630                                     }
1631                                 }
1632                                 error = sooptcopyout(sopt, &optval,
1633                                         sizeof optval);
1634                                 break;
1635
1636                         case IPV6_PKTINFO:
1637                         case IPV6_HOPLIMIT:
1638                         case IPV6_HOPOPTS:
1639                         case IPV6_RTHDR:
1640                         case IPV6_DSTOPTS:
1641                                 if (optname == IPV6_HOPOPTS ||
1642                                     optname == IPV6_DSTOPTS ||
1643                                     !privileged)
1644                                         return(EPERM);
1645                                 switch (optname) {
1646                                 case IPV6_PKTINFO:
1647                                         optval = OPTBIT(IN6P_PKTINFO);
1648                                         break;
1649                                 case IPV6_HOPLIMIT:
1650                                         optval = OPTBIT(IN6P_HOPLIMIT);
1651                                         break;
1652                                 case IPV6_HOPOPTS:
1653                                         if (!privileged)
1654                                                 return(EPERM);
1655                                         optval = OPTBIT(IN6P_HOPOPTS);
1656                                         break;
1657                                 case IPV6_RTHDR:
1658                                         optval = OPTBIT(IN6P_RTHDR);
1659                                         break;
1660                                 case IPV6_DSTOPTS:
1661                                         if (!privileged)
1662                                                 return(EPERM);
1663                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
1664                                         break;
1665                                 }
1666                                 error = sooptcopyout(sopt, &optval,
1667                                         sizeof optval);
1668                                 break;
1669
1670                         case IPV6_MULTICAST_IF:
1671                         case IPV6_MULTICAST_HOPS:
1672                         case IPV6_MULTICAST_LOOP:
1673                         case IPV6_JOIN_GROUP:
1674                         case IPV6_LEAVE_GROUP:
1675                             {
1676                                 struct mbuf *m;
1677                                 error = ip6_getmoptions(sopt->sopt_name,
1678                                                 in6p->in6p_moptions, &m);
1679                                 if (error == 0)
1680                                         error = sooptcopyout(sopt,
1681                                                 mtod(m, char *), m->m_len);
1682                                 m_freem(m);
1683                             }
1684                                 break;
1685
1686 #if defined(IPSEC) || defined(FAST_IPSEC)
1687                         case IPV6_IPSEC_POLICY:
1688                           {
1689                                 caddr_t req = NULL;
1690                                 size_t len = 0;
1691                                 struct mbuf *m = NULL;
1692                                 struct mbuf **mp = &m;
1693
1694                                 error = soopt_getm(sopt, &m); /* XXX */
1695                                 if (error != NULL)
1696                                         break;
1697                                 error = soopt_mcopyin(sopt, m); /* XXX */
1698                                 if (error != NULL)
1699                                         break;
1700                                 if (m) {
1701                                         req = mtod(m, caddr_t);
1702                                         len = m->m_len;
1703                                 }
1704                                 error = ipsec6_get_policy(in6p, req, len, mp);
1705                                 if (error == 0)
1706                                         error = soopt_mcopyout(sopt, m); /*XXX*/
1707                                 if (error == 0 && m)
1708                                         m_freem(m);
1709                                 break;
1710                           }
1711 #endif /* KAME IPSEC */
1712
1713                         case IPV6_FW_GET:
1714                           {
1715                                 struct mbuf *m;
1716                                 struct mbuf **mp = &m;
1717
1718                                 if (ip6_fw_ctl_ptr == NULL)
1719                                 {
1720                                         return EINVAL;
1721                                 }
1722                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
1723                                 if (error == 0)
1724                                         error = soopt_mcopyout(sopt, m); /* XXX */
1725                                 if (error == 0 && m)
1726                                         m_freem(m);
1727                           }
1728                                 break;
1729
1730                         default:
1731                                 error = ENOPROTOOPT;
1732                                 break;
1733                         }
1734                         break;
1735                 }
1736         } else {
1737                 error = EINVAL;
1738         }
1739         return(error);
1740 }
1741
1742 /*
1743  * Set up IP6 options in pcb for insertion in output packets or
1744  * specifying behavior of outgoing packets.
1745  */
1746 static int
1747 ip6_pcbopts(pktopt, m, so, sopt)
1748         struct ip6_pktopts **pktopt;
1749         struct mbuf *m;
1750         struct socket *so;
1751         struct sockopt *sopt;
1752 {
1753         struct ip6_pktopts *opt = *pktopt;
1754         int error = 0;
1755         struct thread *td = sopt->sopt_td;
1756         int priv = 0;
1757
1758         /* turn off any old options. */
1759         if (opt) {
1760 #ifdef DIAGNOSTIC
1761                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
1762                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
1763                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
1764                         printf("ip6_pcbopts: all specified options are cleared.\n");
1765 #endif
1766                 ip6_clearpktopts(opt, 1, -1);
1767         } else
1768                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
1769         *pktopt = NULL;
1770
1771         if (!m || m->m_len == 0) {
1772                 /*
1773                  * Only turning off any previous options, regardless of
1774                  * whether the opt is just created or given.
1775                  */
1776                 free(opt, M_IP6OPT);
1777                 return(0);
1778         }
1779
1780         /*  set options specified by user. */
1781         if (suser(td) == 0)
1782                 priv = 1;
1783         if ((error = ip6_setpktoptions(m, opt, priv, 1)) != 0) {
1784                 ip6_clearpktopts(opt, 1, -1); /* XXX: discard all options */
1785                 free(opt, M_IP6OPT);
1786                 return(error);
1787         }
1788         *pktopt = opt;
1789         return(0);
1790 }
1791
1792 /*
1793  * initialize ip6_pktopts.  beware that there are non-zero default values in
1794  * the struct.
1795  */
1796 void
1797 init_ip6pktopts(opt)
1798         struct ip6_pktopts *opt;
1799 {
1800
1801         bzero(opt, sizeof(*opt));
1802         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
1803 }
1804
1805 void
1806 ip6_clearpktopts(pktopt, needfree, optname)
1807         struct ip6_pktopts *pktopt;
1808         int needfree, optname;
1809 {
1810         if (pktopt == NULL)
1811                 return;
1812
1813         if (optname == -1) {
1814                 if (needfree && pktopt->ip6po_pktinfo)
1815                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
1816                 pktopt->ip6po_pktinfo = NULL;
1817         }
1818         if (optname == -1)
1819                 pktopt->ip6po_hlim = -1;
1820         if (optname == -1) {
1821                 if (needfree && pktopt->ip6po_nexthop)
1822                         free(pktopt->ip6po_nexthop, M_IP6OPT);
1823                 pktopt->ip6po_nexthop = NULL;
1824         }
1825         if (optname == -1) {
1826                 if (needfree && pktopt->ip6po_hbh)
1827                         free(pktopt->ip6po_hbh, M_IP6OPT);
1828                 pktopt->ip6po_hbh = NULL;
1829         }
1830         if (optname == -1) {
1831                 if (needfree && pktopt->ip6po_dest1)
1832                         free(pktopt->ip6po_dest1, M_IP6OPT);
1833                 pktopt->ip6po_dest1 = NULL;
1834         }
1835         if (optname == -1) {
1836                 if (needfree && pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
1837                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
1838                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
1839                 if (pktopt->ip6po_route.ro_rt) {
1840                         RTFREE(pktopt->ip6po_route.ro_rt);
1841                         pktopt->ip6po_route.ro_rt = NULL;
1842                 }
1843         }
1844         if (optname == -1) {
1845                 if (needfree && pktopt->ip6po_dest2)
1846                         free(pktopt->ip6po_dest2, M_IP6OPT);
1847                 pktopt->ip6po_dest2 = NULL;
1848         }
1849 }
1850
1851 #define PKTOPT_EXTHDRCPY(type) \
1852 do {\
1853         if (src->type) {\
1854                 int hlen =\
1855                         (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
1856                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
1857                 if (dst->type == NULL && canwait == M_NOWAIT)\
1858                         goto bad;\
1859                 bcopy(src->type, dst->type, hlen);\
1860         }\
1861 } while (0)
1862
1863 struct ip6_pktopts *
1864 ip6_copypktopts(src, canwait)
1865         struct ip6_pktopts *src;
1866         int canwait;
1867 {
1868         struct ip6_pktopts *dst;
1869
1870         if (src == NULL) {
1871                 printf("ip6_clearpktopts: invalid argument\n");
1872                 return(NULL);
1873         }
1874
1875         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
1876         if (dst == NULL && canwait == M_NOWAIT)
1877                 return (NULL);
1878         bzero(dst, sizeof(*dst));
1879
1880         dst->ip6po_hlim = src->ip6po_hlim;
1881         if (src->ip6po_pktinfo) {
1882                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
1883                                             M_IP6OPT, canwait);
1884                 if (dst->ip6po_pktinfo == NULL && canwait == M_NOWAIT)
1885                         goto bad;
1886                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
1887         }
1888         if (src->ip6po_nexthop) {
1889                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
1890                                             M_IP6OPT, canwait);
1891                 if (dst->ip6po_nexthop == NULL && canwait == M_NOWAIT)
1892                         goto bad;
1893                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
1894                       src->ip6po_nexthop->sa_len);
1895         }
1896         PKTOPT_EXTHDRCPY(ip6po_hbh);
1897         PKTOPT_EXTHDRCPY(ip6po_dest1);
1898         PKTOPT_EXTHDRCPY(ip6po_dest2);
1899         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
1900         return(dst);
1901
1902   bad:
1903         if (dst->ip6po_pktinfo) free(dst->ip6po_pktinfo, M_IP6OPT);
1904         if (dst->ip6po_nexthop) free(dst->ip6po_nexthop, M_IP6OPT);
1905         if (dst->ip6po_hbh) free(dst->ip6po_hbh, M_IP6OPT);
1906         if (dst->ip6po_dest1) free(dst->ip6po_dest1, M_IP6OPT);
1907         if (dst->ip6po_dest2) free(dst->ip6po_dest2, M_IP6OPT);
1908         if (dst->ip6po_rthdr) free(dst->ip6po_rthdr, M_IP6OPT);
1909         free(dst, M_IP6OPT);
1910         return(NULL);
1911 }
1912 #undef PKTOPT_EXTHDRCPY
1913
1914 void
1915 ip6_freepcbopts(pktopt)
1916         struct ip6_pktopts *pktopt;
1917 {
1918         if (pktopt == NULL)
1919                 return;
1920
1921         ip6_clearpktopts(pktopt, 1, -1);
1922
1923         free(pktopt, M_IP6OPT);
1924 }
1925
1926 /*
1927  * Set the IP6 multicast options in response to user setsockopt().
1928  */
1929 static int
1930 ip6_setmoptions(optname, im6op, m)
1931         int optname;
1932         struct ip6_moptions **im6op;
1933         struct mbuf *m;
1934 {
1935         int error = 0;
1936         u_int loop, ifindex;
1937         struct ipv6_mreq *mreq;
1938         struct ifnet *ifp;
1939         struct ip6_moptions *im6o = *im6op;
1940         struct route_in6 ro;
1941         struct sockaddr_in6 *dst;
1942         struct in6_multi_mship *imm;
1943         struct thread *td = curthread;  /* XXX */
1944
1945         if (im6o == NULL) {
1946                 /*
1947                  * No multicast option buffer attached to the pcb;
1948                  * allocate one and initialize to default values.
1949                  */
1950                 im6o = (struct ip6_moptions *)
1951                         malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK);
1952
1953                 if (im6o == NULL)
1954                         return(ENOBUFS);
1955                 *im6op = im6o;
1956                 im6o->im6o_multicast_ifp = NULL;
1957                 im6o->im6o_multicast_hlim = ip6_defmcasthlim;
1958                 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP;
1959                 LIST_INIT(&im6o->im6o_memberships);
1960         }
1961
1962         switch (optname) {
1963
1964         case IPV6_MULTICAST_IF:
1965                 /*
1966                  * Select the interface for outgoing multicast packets.
1967                  */
1968                 if (m == NULL || m->m_len != sizeof(u_int)) {
1969                         error = EINVAL;
1970                         break;
1971                 }
1972                 bcopy(mtod(m, u_int *), &ifindex, sizeof(ifindex));
1973                 if (ifindex < 0 || if_index < ifindex) {
1974                         error = ENXIO;  /* XXX EINVAL? */
1975                         break;
1976                 }
1977                 ifp = ifindex2ifnet[ifindex];
1978                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
1979                         error = EADDRNOTAVAIL;
1980                         break;
1981                 }
1982                 im6o->im6o_multicast_ifp = ifp;
1983                 break;
1984
1985         case IPV6_MULTICAST_HOPS:
1986             {
1987                 /*
1988                  * Set the IP6 hoplimit for outgoing multicast packets.
1989                  */
1990                 int optval;
1991                 if (m == NULL || m->m_len != sizeof(int)) {
1992                         error = EINVAL;
1993                         break;
1994                 }
1995                 bcopy(mtod(m, u_int *), &optval, sizeof(optval));
1996                 if (optval < -1 || optval >= 256)
1997                         error = EINVAL;
1998                 else if (optval == -1)
1999                         im6o->im6o_multicast_hlim = ip6_defmcasthlim;
2000                 else
2001                         im6o->im6o_multicast_hlim = optval;
2002                 break;
2003             }
2004
2005         case IPV6_MULTICAST_LOOP:
2006                 /*
2007                  * Set the loopback flag for outgoing multicast packets.
2008                  * Must be zero or one.
2009                  */
2010                 if (m == NULL || m->m_len != sizeof(u_int)) {
2011                         error = EINVAL;
2012                         break;
2013                 }
2014                 bcopy(mtod(m, u_int *), &loop, sizeof(loop));
2015                 if (loop > 1) {
2016                         error = EINVAL;
2017                         break;
2018                 }
2019                 im6o->im6o_multicast_loop = loop;
2020                 break;
2021
2022         case IPV6_JOIN_GROUP:
2023                 /*
2024                  * Add a multicast group membership.
2025                  * Group must be a valid IP6 multicast address.
2026                  */
2027                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2028                         error = EINVAL;
2029                         break;
2030                 }
2031                 mreq = mtod(m, struct ipv6_mreq *);
2032                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2033                         /*
2034                          * We use the unspecified address to specify to accept
2035                          * all multicast addresses. Only super user is allowed
2036                          * to do this.
2037                          */
2038                         if (suser(td))
2039                         {
2040                                 error = EACCES;
2041                                 break;
2042                         }
2043                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2044                         error = EINVAL;
2045                         break;
2046                 }
2047
2048                 /*
2049                  * If the interface is specified, validate it.
2050                  */
2051                 if (mreq->ipv6mr_interface < 0
2052                  || if_index < mreq->ipv6mr_interface) {
2053                         error = ENXIO;  /* XXX EINVAL? */
2054                         break;
2055                 }
2056                 /*
2057                  * If no interface was explicitly specified, choose an
2058                  * appropriate one according to the given multicast address.
2059                  */
2060                 if (mreq->ipv6mr_interface == 0) {
2061                         /*
2062                          * If the multicast address is in node-local scope,
2063                          * the interface should be a loopback interface.
2064                          * Otherwise, look up the routing table for the
2065                          * address, and choose the outgoing interface.
2066                          *   XXX: is it a good approach?
2067                          */
2068                         if (IN6_IS_ADDR_MC_NODELOCAL(&mreq->ipv6mr_multiaddr)) {
2069                                 ifp = &loif[0];
2070                         } else {
2071                                 ro.ro_rt = NULL;
2072                                 dst = (struct sockaddr_in6 *)&ro.ro_dst;
2073                                 bzero(dst, sizeof(*dst));
2074                                 dst->sin6_len = sizeof(struct sockaddr_in6);
2075                                 dst->sin6_family = AF_INET6;
2076                                 dst->sin6_addr = mreq->ipv6mr_multiaddr;
2077                                 rtalloc((struct route *)&ro);
2078                                 if (ro.ro_rt == NULL) {
2079                                         error = EADDRNOTAVAIL;
2080                                         break;
2081                                 }
2082                                 ifp = ro.ro_rt->rt_ifp;
2083                                 rtfree(ro.ro_rt);
2084                         }
2085                 } else
2086                         ifp = ifindex2ifnet[mreq->ipv6mr_interface];
2087
2088                 /*
2089                  * See if we found an interface, and confirm that it
2090                  * supports multicast
2091                  */
2092                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
2093                         error = EADDRNOTAVAIL;
2094                         break;
2095                 }
2096                 /*
2097                  * Put interface index into the multicast address,
2098                  * if the address has link-local scope.
2099                  */
2100                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2101                         mreq->ipv6mr_multiaddr.s6_addr16[1]
2102                                 = htons(mreq->ipv6mr_interface);
2103                 }
2104                 /*
2105                  * See if the membership already exists.
2106                  */
2107                 for (imm = im6o->im6o_memberships.lh_first;
2108                      imm != NULL; imm = imm->i6mm_chain.le_next)
2109                         if (imm->i6mm_maddr->in6m_ifp == ifp &&
2110                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2111                                                &mreq->ipv6mr_multiaddr))
2112                                 break;
2113                 if (imm != NULL) {
2114                         error = EADDRINUSE;
2115                         break;
2116                 }
2117                 /*
2118                  * Everything looks good; add a new record to the multicast
2119                  * address list for the given interface.
2120                  */
2121                 imm = malloc(sizeof(*imm), M_IPMADDR, M_WAITOK);
2122                 if (imm == NULL) {
2123                         error = ENOBUFS;
2124                         break;
2125                 }
2126                 if ((imm->i6mm_maddr =
2127                      in6_addmulti(&mreq->ipv6mr_multiaddr, ifp, &error)) == NULL) {
2128                         free(imm, M_IPMADDR);
2129                         break;
2130                 }
2131                 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
2132                 break;
2133
2134         case IPV6_LEAVE_GROUP:
2135                 /*
2136                  * Drop a multicast group membership.
2137                  * Group must be a valid IP6 multicast address.
2138                  */
2139                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2140                         error = EINVAL;
2141                         break;
2142                 }
2143                 mreq = mtod(m, struct ipv6_mreq *);
2144                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2145                         if (suser(td)) {
2146                                 error = EACCES;
2147                                 break;
2148                         }
2149                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2150                         error = EINVAL;
2151                         break;
2152                 }
2153                 /*
2154                  * If an interface address was specified, get a pointer
2155                  * to its ifnet structure.
2156                  */
2157                 if (mreq->ipv6mr_interface < 0
2158                  || if_index < mreq->ipv6mr_interface) {
2159                         error = ENXIO;  /* XXX EINVAL? */
2160                         break;
2161                 }
2162                 ifp = ifindex2ifnet[mreq->ipv6mr_interface];
2163                 /*
2164                  * Put interface index into the multicast address,
2165                  * if the address has link-local scope.
2166                  */
2167                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2168                         mreq->ipv6mr_multiaddr.s6_addr16[1]
2169                                 = htons(mreq->ipv6mr_interface);
2170                 }
2171                 /*
2172                  * Find the membership in the membership list.
2173                  */
2174                 for (imm = im6o->im6o_memberships.lh_first;
2175                      imm != NULL; imm = imm->i6mm_chain.le_next) {
2176                         if ((ifp == NULL ||
2177                              imm->i6mm_maddr->in6m_ifp == ifp) &&
2178                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2179                                                &mreq->ipv6mr_multiaddr))
2180                                 break;
2181                 }
2182                 if (imm == NULL) {
2183                         /* Unable to resolve interface */
2184                         error = EADDRNOTAVAIL;
2185                         break;
2186                 }
2187                 /*
2188                  * Give up the multicast address record to which the
2189                  * membership points.
2190                  */
2191                 LIST_REMOVE(imm, i6mm_chain);
2192                 in6_delmulti(imm->i6mm_maddr);
2193                 free(imm, M_IPMADDR);
2194                 break;
2195
2196         default:
2197                 error = EOPNOTSUPP;
2198                 break;
2199         }
2200
2201         /*
2202          * If all options have default values, no need to keep the mbuf.
2203          */
2204         if (im6o->im6o_multicast_ifp == NULL &&
2205             im6o->im6o_multicast_hlim == ip6_defmcasthlim &&
2206             im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP &&
2207             im6o->im6o_memberships.lh_first == NULL) {
2208                 free(*im6op, M_IPMOPTS);
2209                 *im6op = NULL;
2210         }
2211
2212         return(error);
2213 }
2214
2215 /*
2216  * Return the IP6 multicast options in response to user getsockopt().
2217  */
2218 static int
2219 ip6_getmoptions(optname, im6o, mp)
2220         int optname;
2221         struct ip6_moptions *im6o;
2222         struct mbuf **mp;
2223 {
2224         u_int *hlim, *loop, *ifindex;
2225
2226         *mp = m_get(M_WAIT, MT_HEADER);         /* XXX */
2227
2228         switch (optname) {
2229
2230         case IPV6_MULTICAST_IF:
2231                 ifindex = mtod(*mp, u_int *);
2232                 (*mp)->m_len = sizeof(u_int);
2233                 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL)
2234                         *ifindex = 0;
2235                 else
2236                         *ifindex = im6o->im6o_multicast_ifp->if_index;
2237                 return(0);
2238
2239         case IPV6_MULTICAST_HOPS:
2240                 hlim = mtod(*mp, u_int *);
2241                 (*mp)->m_len = sizeof(u_int);
2242                 if (im6o == NULL)
2243                         *hlim = ip6_defmcasthlim;
2244                 else
2245                         *hlim = im6o->im6o_multicast_hlim;
2246                 return(0);
2247
2248         case IPV6_MULTICAST_LOOP:
2249                 loop = mtod(*mp, u_int *);
2250                 (*mp)->m_len = sizeof(u_int);
2251                 if (im6o == NULL)
2252                         *loop = ip6_defmcasthlim;
2253                 else
2254                         *loop = im6o->im6o_multicast_loop;
2255                 return(0);
2256
2257         default:
2258                 return(EOPNOTSUPP);
2259         }
2260 }
2261
2262 /*
2263  * Discard the IP6 multicast options.
2264  */
2265 void
2266 ip6_freemoptions(im6o)
2267         struct ip6_moptions *im6o;
2268 {
2269         struct in6_multi_mship *imm;
2270
2271         if (im6o == NULL)
2272                 return;
2273
2274         while ((imm = im6o->im6o_memberships.lh_first) != NULL) {
2275                 LIST_REMOVE(imm, i6mm_chain);
2276                 if (imm->i6mm_maddr)
2277                         in6_delmulti(imm->i6mm_maddr);
2278                 free(imm, M_IPMADDR);
2279         }
2280         free(im6o, M_IPMOPTS);
2281 }
2282
2283 /*
2284  * Set IPv6 outgoing packet options based on advanced API.
2285  */
2286 int
2287 ip6_setpktoptions(control, opt, priv, needcopy)
2288         struct mbuf *control;
2289         struct ip6_pktopts *opt;
2290         int priv, needcopy;
2291 {
2292         struct cmsghdr *cm = 0;
2293
2294         if (control == 0 || opt == 0)
2295                 return(EINVAL);
2296
2297         init_ip6pktopts(opt);
2298
2299         /*
2300          * XXX: Currently, we assume all the optional information is stored
2301          * in a single mbuf.
2302          */
2303         if (control->m_next)
2304                 return(EINVAL);
2305
2306         for (; control->m_len; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2307                      control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2308                 cm = mtod(control, struct cmsghdr *);
2309                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2310                         return(EINVAL);
2311                 if (cm->cmsg_level != IPPROTO_IPV6)
2312                         continue;
2313
2314                 /*
2315                  * XXX should check if RFC2292 API is mixed with 2292bis API
2316                  */
2317                 switch (cm->cmsg_type) {
2318                 case IPV6_PKTINFO:
2319                         if (cm->cmsg_len != CMSG_LEN(sizeof(struct in6_pktinfo)))
2320                                 return(EINVAL);
2321                         if (needcopy) {
2322                                 /* XXX: Is it really WAITOK? */
2323                                 opt->ip6po_pktinfo =
2324                                         malloc(sizeof(struct in6_pktinfo),
2325                                                M_IP6OPT, M_WAITOK);
2326                                 bcopy(CMSG_DATA(cm), opt->ip6po_pktinfo,
2327                                     sizeof(struct in6_pktinfo));
2328                         } else
2329                                 opt->ip6po_pktinfo =
2330                                         (struct in6_pktinfo *)CMSG_DATA(cm);
2331                         if (opt->ip6po_pktinfo->ipi6_ifindex &&
2332                             IN6_IS_ADDR_LINKLOCAL(&opt->ip6po_pktinfo->ipi6_addr))
2333                                 opt->ip6po_pktinfo->ipi6_addr.s6_addr16[1] =
2334                                         htons(opt->ip6po_pktinfo->ipi6_ifindex);
2335
2336                         if (opt->ip6po_pktinfo->ipi6_ifindex > if_index
2337                          || opt->ip6po_pktinfo->ipi6_ifindex < 0) {
2338                                 return(ENXIO);
2339                         }
2340
2341                         /*
2342                          * Check if the requested source address is indeed a
2343                          * unicast address assigned to the node, and can be
2344                          * used as the packet's source address.
2345                          */
2346                         if (!IN6_IS_ADDR_UNSPECIFIED(&opt->ip6po_pktinfo->ipi6_addr)) {
2347                                 struct in6_ifaddr *ia6;
2348                                 struct sockaddr_in6 sin6;
2349
2350                                 bzero(&sin6, sizeof(sin6));
2351                                 sin6.sin6_len = sizeof(sin6);
2352                                 sin6.sin6_family = AF_INET6;
2353                                 sin6.sin6_addr =
2354                                         opt->ip6po_pktinfo->ipi6_addr;
2355                                 ia6 = (struct in6_ifaddr *)ifa_ifwithaddr(sin6tosa(&sin6));
2356                                 if (ia6 == NULL ||
2357                                     (ia6->ia6_flags & (IN6_IFF_ANYCAST |
2358                                                        IN6_IFF_NOTREADY)) != 0)
2359                                         return(EADDRNOTAVAIL);
2360                         }
2361                         break;
2362
2363                 case IPV6_HOPLIMIT:
2364                         if (cm->cmsg_len != CMSG_LEN(sizeof(int)))
2365                                 return(EINVAL);
2366
2367                         opt->ip6po_hlim = *(int *)CMSG_DATA(cm);
2368                         if (opt->ip6po_hlim < -1 || opt->ip6po_hlim > 255)
2369                                 return(EINVAL);
2370                         break;
2371
2372                 case IPV6_NEXTHOP:
2373                         if (!priv)
2374                                 return(EPERM);
2375
2376                         if (cm->cmsg_len < sizeof(u_char) ||
2377                             /* check if cmsg_len is large enough for sa_len */
2378                             cm->cmsg_len < CMSG_LEN(*CMSG_DATA(cm)))
2379                                 return(EINVAL);
2380
2381                         if (needcopy) {
2382                                 opt->ip6po_nexthop =
2383                                         malloc(*CMSG_DATA(cm),
2384                                                M_IP6OPT, M_WAITOK);
2385                                 bcopy(CMSG_DATA(cm),
2386                                       opt->ip6po_nexthop,
2387                                       *CMSG_DATA(cm));
2388                         } else
2389                                 opt->ip6po_nexthop =
2390                                         (struct sockaddr *)CMSG_DATA(cm);
2391                         break;
2392
2393                 case IPV6_HOPOPTS:
2394                 {
2395                         struct ip6_hbh *hbh;
2396                         int hbhlen;
2397
2398                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_hbh)))
2399                                 return(EINVAL);
2400                         hbh = (struct ip6_hbh *)CMSG_DATA(cm);
2401                         hbhlen = (hbh->ip6h_len + 1) << 3;
2402                         if (cm->cmsg_len != CMSG_LEN(hbhlen))
2403                                 return(EINVAL);
2404
2405                         if (needcopy) {
2406                                 opt->ip6po_hbh =
2407                                         malloc(hbhlen, M_IP6OPT, M_WAITOK);
2408                                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2409                         } else
2410                                 opt->ip6po_hbh = hbh;
2411                         break;
2412                 }
2413
2414                 case IPV6_DSTOPTS:
2415                 {
2416                         struct ip6_dest *dest, **newdest;
2417                         int destlen;
2418
2419                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_dest)))
2420                                 return(EINVAL);
2421                         dest = (struct ip6_dest *)CMSG_DATA(cm);
2422                         destlen = (dest->ip6d_len + 1) << 3;
2423                         if (cm->cmsg_len != CMSG_LEN(destlen))
2424                                 return(EINVAL);
2425
2426                         /*
2427                          * The old advacned API is ambiguous on this
2428                          * point. Our approach is to determine the
2429                          * position based according to the existence
2430                          * of a routing header. Note, however, that
2431                          * this depends on the order of the extension
2432                          * headers in the ancillary data; the 1st part
2433                          * of the destination options header must
2434                          * appear before the routing header in the
2435                          * ancillary data, too.
2436                          * RFC2292bis solved the ambiguity by
2437                          * introducing separate cmsg types.
2438                          */
2439                         if (opt->ip6po_rthdr == NULL)
2440                                 newdest = &opt->ip6po_dest1;
2441                         else
2442                                 newdest = &opt->ip6po_dest2;
2443
2444                         if (needcopy) {
2445                                 *newdest = malloc(destlen, M_IP6OPT, M_WAITOK);
2446                                 bcopy(dest, *newdest, destlen);
2447                         } else
2448                                 *newdest = dest;
2449
2450                         break;
2451                 }
2452
2453                 case IPV6_RTHDR:
2454                 {
2455                         struct ip6_rthdr *rth;
2456                         int rthlen;
2457
2458                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_rthdr)))
2459                                 return(EINVAL);
2460                         rth = (struct ip6_rthdr *)CMSG_DATA(cm);
2461                         rthlen = (rth->ip6r_len + 1) << 3;
2462                         if (cm->cmsg_len != CMSG_LEN(rthlen))
2463                                 return(EINVAL);
2464
2465                         switch (rth->ip6r_type) {
2466                         case IPV6_RTHDR_TYPE_0:
2467                                 /* must contain one addr */
2468                                 if (rth->ip6r_len == 0)
2469                                         return(EINVAL);
2470                                 /* length must be even */
2471                                 if (rth->ip6r_len % 2)
2472                                         return(EINVAL);
2473                                 if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2474                                         return(EINVAL);
2475                                 break;
2476                         default:
2477                                 return(EINVAL); /* not supported */
2478                         }
2479
2480                         if (needcopy) {
2481                                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT,
2482                                                           M_WAITOK);
2483                                 bcopy(rth, opt->ip6po_rthdr, rthlen);
2484                         } else
2485                                 opt->ip6po_rthdr = rth;
2486
2487                         break;
2488                 }
2489
2490                 default:
2491                         return(ENOPROTOOPT);
2492                 }
2493         }
2494
2495         return(0);
2496 }
2497
2498 /*
2499  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2500  * packet to the input queue of a specified interface.  Note that this
2501  * calls the output routine of the loopback "driver", but with an interface
2502  * pointer that might NOT be &loif -- easier than replicating that code here.
2503  */
2504 void
2505 ip6_mloopback(ifp, m, dst)
2506         struct ifnet *ifp;
2507         struct mbuf *m;
2508         struct sockaddr_in6 *dst;
2509 {
2510         struct mbuf *copym;
2511         struct ip6_hdr *ip6;
2512
2513         copym = m_copy(m, 0, M_COPYALL);
2514         if (copym == NULL)
2515                 return;
2516
2517         /*
2518          * Make sure to deep-copy IPv6 header portion in case the data
2519          * is in an mbuf cluster, so that we can safely override the IPv6
2520          * header portion later.
2521          */
2522         if ((copym->m_flags & M_EXT) != 0 ||
2523             copym->m_len < sizeof(struct ip6_hdr)) {
2524                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
2525                 if (copym == NULL)
2526                         return;
2527         }
2528
2529 #ifdef DIAGNOSTIC
2530         if (copym->m_len < sizeof(*ip6)) {
2531                 m_freem(copym);
2532                 return;
2533         }
2534 #endif
2535
2536         ip6 = mtod(copym, struct ip6_hdr *);
2537 #ifndef SCOPEDROUTING
2538         /*
2539          * clear embedded scope identifiers if necessary.
2540          * in6_clearscope will touch the addresses only when necessary.
2541          */
2542         in6_clearscope(&ip6->ip6_src);
2543         in6_clearscope(&ip6->ip6_dst);
2544 #endif
2545
2546         (void)if_simloop(ifp, copym, dst->sin6_family, NULL);
2547 }
2548
2549 /*
2550  * Chop IPv6 header off from the payload.
2551  */
2552 static int
2553 ip6_splithdr(m, exthdrs)
2554         struct mbuf *m;
2555         struct ip6_exthdrs *exthdrs;
2556 {
2557         struct mbuf *mh;
2558         struct ip6_hdr *ip6;
2559
2560         ip6 = mtod(m, struct ip6_hdr *);
2561         if (m->m_len > sizeof(*ip6)) {
2562                 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
2563                 if (mh == 0) {
2564                         m_freem(m);
2565                         return ENOBUFS;
2566                 }
2567                 M_MOVE_PKTHDR(mh, m);
2568                 MH_ALIGN(mh, sizeof(*ip6));
2569                 m->m_len -= sizeof(*ip6);
2570                 m->m_data += sizeof(*ip6);
2571                 mh->m_next = m;
2572                 m = mh;
2573                 m->m_len = sizeof(*ip6);
2574                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
2575         }
2576         exthdrs->ip6e_ip6 = m;
2577         return 0;
2578 }
2579
2580 /*
2581  * Compute IPv6 extension header length.
2582  */
2583 int
2584 ip6_optlen(in6p)
2585         struct in6pcb *in6p;
2586 {
2587         int len;
2588
2589         if (!in6p->in6p_outputopts)
2590                 return 0;
2591
2592         len = 0;
2593 #define elen(x) \
2594     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
2595
2596         len += elen(in6p->in6p_outputopts->ip6po_hbh);
2597         if (in6p->in6p_outputopts->ip6po_rthdr)
2598                 /* dest1 is valid with rthdr only */
2599                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
2600         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
2601         len += elen(in6p->in6p_outputopts->ip6po_dest2);
2602         return len;
2603 #undef elen
2604 }