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 1.9 2003/12/02 08:00:22 asmodai 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 #include "opt_pfil_hooks.h"
  74
  75 #include <sys/param.h>
  76 #include <sys/malloc.h>
  77 #include <sys/mbuf.h>
  78 #include <sys/errno.h>
  79 #include <sys/protosw.h>
  80 #include <sys/socket.h>
  81 #include <sys/socketvar.h>
  82 #include <sys/systm.h>
  83 #include <sys/kernel.h>
  84 #include <sys/proc.h>
  85
  86 #include <net/if.h>
  87 #include <net/route.h>
  88 #ifdef PFIL_HOOKS
  89 #include <net/pfil.h>
  90 #endif
  91
  92 #include <netinet/in.h>
  93 #include <netinet/in_var.h>
  94 #include <netinet6/in6_var.h>
  95 #include <netinet/ip6.h>
  96 #include <netinet/icmp6.h>
  97 #include <netinet6/ip6_var.h>
  98 #include <netinet/in_pcb.h>
  99 #include <netinet6/nd6.h>
 100
 101 #ifdef IPSEC
 102 #include <netinet6/ipsec.h>
 103 #ifdef INET6
 104 #include <netinet6/ipsec6.h>
 105 #endif
 106 #include <netproto/key/key.h>
 107 #endif /* IPSEC */
 108
 109 #ifdef FAST_IPSEC
 110 #include "ipsec.h"
 111 #include "ipsec6.h"
 112 #include <netipsec/key.h>
 113 #endif /* FAST_IPSEC */
 114
 115 #include <net/ip6fw/ip6_fw.h>
 116
 117 #include <net/net_osdep.h>
 118
 119 static MALLOC_DEFINE(M_IPMOPTS, "ip6_moptions", "internet multicast options");
 120
 121 struct ip6_exthdrs {
 122         struct mbuf *ip6e_ip6;
 123         struct mbuf *ip6e_hbh;
 124         struct mbuf *ip6e_dest1;
 125         struct mbuf *ip6e_rthdr;
 126         struct mbuf *ip6e_dest2;
 127 };
 128
 129 static int ip6_pcbopts (struct ip6_pktopts **, struct mbuf *,
 130                             struct socket *, struct sockopt *sopt);
 131 static int ip6_setmoptions (int, struct ip6_moptions **, struct mbuf *);
 132 static int ip6_getmoptions (int, struct ip6_moptions *, struct mbuf **);
 133 static int ip6_copyexthdr (struct mbuf **, caddr_t, int);
 134 static int ip6_insertfraghdr (struct mbuf *, struct mbuf *, int,
 135                                   struct ip6_frag **);
 136 static int ip6_insert_jumboopt (struct ip6_exthdrs *, u_int32_t);
 137 static int ip6_splithdr (struct mbuf *, struct ip6_exthdrs *);
 138
 139 /*
 140  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 141  * header (with pri, len, nxt, hlim, src, dst).
 142  * This function may modify ver and hlim only.
 143  * The mbuf chain containing the packet will be freed.
 144  * The mbuf opt, if present, will not be freed.
 145  *
 146  * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and
 147  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 148  * which is rt_rmx.rmx_mtu.
 149  */
 150 int
 151 ip6_output(m0, opt, ro, flags, im6o, ifpp, inp)
 152         struct mbuf *m0;
 153         struct ip6_pktopts *opt;
 154         struct route_in6 *ro;
 155         int flags;
 156         struct ip6_moptions *im6o;
 157         struct ifnet **ifpp;            /* XXX: just for statistics */
 158         struct inpcb *inp;
 159 {
 160         struct ip6_hdr *ip6, *mhip6;
 161         struct ifnet *ifp, *origifp;
 162         struct mbuf *m = m0;
 163         int hlen, tlen, len, off;
 164         struct route_in6 ip6route;
 165         struct sockaddr_in6 *dst;
 166         int error = 0;
 167         struct in6_ifaddr *ia = NULL;
 168         u_long mtu;
 169         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 170         struct ip6_exthdrs exthdrs;
 171         struct in6_addr finaldst;
 172         struct route_in6 *ro_pmtu = NULL;
 173         int hdrsplit = 0;
 174         int needipsec = 0;
 175 #ifdef IPSEC
 176         int needipsectun = 0;
 177         struct secpolicy *sp = NULL;
 178         struct socket *so = inp ? inp->inp_socket : NULL;
 179
 180         ip6 = mtod(m, struct ip6_hdr *);
 181 #endif /* IPSEC */
 182 #ifdef FAST_IPSEC
 183         int needipsectun = 0;
 184         struct secpolicy *sp = NULL;
 185
 186         ip6 = mtod(m, struct ip6_hdr *);
 187 #endif /* FAST_IPSEC */
 188
 189 #define MAKE_EXTHDR(hp, mp)                                             \
 190     do {                                                                \
 191         if (hp) {                                                       \
 192                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 193                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 194                                        ((eh)->ip6e_len + 1) << 3);      \
 195                 if (error)                                              \
 196                         goto freehdrs;                                  \
 197         }                                                               \
 198     } while (0)
 199
 200         bzero(&exthdrs, sizeof(exthdrs));
 201
 202         if (opt) {
 203                 /* Hop-by-Hop options header */
 204                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 205                 /* Destination options header(1st part) */
 206                 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 207                 /* Routing header */
 208                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 209                 /* Destination options header(2nd part) */
 210                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 211         }
 212
 213 #ifdef IPSEC
 214         /* get a security policy for this packet */
 215         if (so == NULL)
 216                 sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
 217         else
 218                 sp = ipsec6_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
 219
 220         if (sp == NULL) {
 221                 ipsec6stat.out_inval++;
 222                 goto freehdrs;
 223         }
 224
 225         error = 0;
 226
 227         /* check policy */
 228         switch (sp->policy) {
 229         case IPSEC_POLICY_DISCARD:
 230                 /*
 231                  * This packet is just discarded.
 232                  */
 233                 ipsec6stat.out_polvio++;
 234                 goto freehdrs;
 235
 236         case IPSEC_POLICY_BYPASS:
 237         case IPSEC_POLICY_NONE:
 238                 /* no need to do IPsec. */
 239                 needipsec = 0;
 240                 break;
 241
 242         case IPSEC_POLICY_IPSEC:
 243                 if (sp->req == NULL) {
 244                         /* acquire a policy */
 245                         error = key_spdacquire(sp);
 246                         goto freehdrs;
 247                 }
 248                 needipsec = 1;
 249                 break;
 250
 251         case IPSEC_POLICY_ENTRUST:
 252         default:
 253                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
 254         }
 255 #endif /* IPSEC */
 256 #ifdef FAST_IPSEC
 257         /* get a security policy for this packet */
 258         if (inp == NULL)
 259                 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
 260         else
 261                 sp = ipsec_getpolicybysock(m, IPSEC_DIR_OUTBOUND, inp, &error);
 262
 263         if (sp == NULL) {
 264                 newipsecstat.ips_out_inval++;
 265                 goto freehdrs;
 266         }
 267
 268         error = 0;
 269
 270         /* check policy */
 271         switch (sp->policy) {
 272         case IPSEC_POLICY_DISCARD:
 273                 /*
 274                  * This packet is just discarded.
 275                  */
 276                 newipsecstat.ips_out_polvio++;
 277                 goto freehdrs;
 278
 279         case IPSEC_POLICY_BYPASS:
 280         case IPSEC_POLICY_NONE:
 281                 /* no need to do IPsec. */
 282                 needipsec = 0;
 283                 break;
 284
 285         case IPSEC_POLICY_IPSEC:
 286                 if (sp->req == NULL) {
 287                         /* acquire a policy */
 288                         error = key_spdacquire(sp);
 289                         goto freehdrs;
 290                 }
 291                 needipsec = 1;
 292                 break;
 293
 294         case IPSEC_POLICY_ENTRUST:
 295         default:
 296                 printf("ip6_output: Invalid policy found. %d\n", sp->policy);
 297         }
 298 #endif /* FAST_IPSEC */
 299
 300         /*
 301          * Calculate the total length of the extension header chain.
 302          * Keep the length of the unfragmentable part for fragmentation.
 303          */
 304         optlen = 0;
 305         if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len;
 306         if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len;
 307         if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len;
 308         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 309         /* NOTE: we don't add AH/ESP length here. do that later. */
 310         if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len;
 311
 312         /*
 313          * If we need IPsec, or there is at least one extension header,
 314          * separate IP6 header from the payload.
 315          */
 316         if ((needipsec || optlen) && !hdrsplit) {
 317                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 318                         m = NULL;
 319                         goto freehdrs;
 320                 }
 321                 m = exthdrs.ip6e_ip6;
 322                 hdrsplit++;
 323         }
 324
 325         /* adjust pointer */
 326         ip6 = mtod(m, struct ip6_hdr *);
 327
 328         /* adjust mbuf packet header length */
 329         m->m_pkthdr.len += optlen;
 330         plen = m->m_pkthdr.len - sizeof(*ip6);
 331
 332         /* If this is a jumbo payload, insert a jumbo payload option. */
 333         if (plen > IPV6_MAXPACKET) {
 334                 if (!hdrsplit) {
 335                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 336                                 m = NULL;
 337                                 goto freehdrs;
 338                         }
 339                         m = exthdrs.ip6e_ip6;
 340                         hdrsplit++;
 341                 }
 342                 /* adjust pointer */
 343                 ip6 = mtod(m, struct ip6_hdr *);
 344                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 345                         goto freehdrs;
 346                 ip6->ip6_plen = 0;
 347         } else
 348                 ip6->ip6_plen = htons(plen);
 349
 350         /*
 351          * Concatenate headers and fill in next header fields.
 352          * Here we have, on "m"
 353          *      IPv6 payload
 354          * and we insert headers accordingly.  Finally, we should be getting:
 355          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 356          *
 357          * during the header composing process, "m" points to IPv6 header.
 358          * "mprev" points to an extension header prior to esp.
 359          */
 360         {
 361                 u_char *nexthdrp = &ip6->ip6_nxt;
 362                 struct mbuf *mprev = m;
 363
 364                 /*
 365                  * we treat dest2 specially.  this makes IPsec processing
 366                  * much easier.  the goal here is to make mprev point the
 367                  * mbuf prior to dest2.
 368                  *
 369                  * result: IPv6 dest2 payload
 370                  * m and mprev will point to IPv6 header.
 371                  */
 372                 if (exthdrs.ip6e_dest2) {
 373                         if (!hdrsplit)
 374                                 panic("assumption failed: hdr not split");
 375                         exthdrs.ip6e_dest2->m_next = m->m_next;
 376                         m->m_next = exthdrs.ip6e_dest2;
 377                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 378                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 379                 }
 380
 381 #define MAKE_CHAIN(m, mp, p, i)\
 382     do {\
 383         if (m) {\
 384                 if (!hdrsplit) \
 385                         panic("assumption failed: hdr not split"); \
 386                 *mtod((m), u_char *) = *(p);\
 387                 *(p) = (i);\
 388                 p = mtod((m), u_char *);\
 389                 (m)->m_next = (mp)->m_next;\
 390                 (mp)->m_next = (m);\
 391                 (mp) = (m);\
 392         }\
 393     } while (0)
 394                 /*
 395                  * result: IPv6 hbh dest1 rthdr dest2 payload
 396                  * m will point to IPv6 header.  mprev will point to the
 397                  * extension header prior to dest2 (rthdr in the above case).
 398                  */
 399                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev,
 400                            nexthdrp, IPPROTO_HOPOPTS);
 401                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev,
 402                            nexthdrp, IPPROTO_DSTOPTS);
 403                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev,
 404                            nexthdrp, IPPROTO_ROUTING);
 405
 406 #if defined(IPSEC) || defined(FAST_IPSEC)
 407                 if (!needipsec)
 408                         goto skip_ipsec2;
 409
 410                 /*
 411                  * pointers after IPsec headers are not valid any more.
 412                  * other pointers need a great care too.
 413                  * (IPsec routines should not mangle mbufs prior to AH/ESP)
 414                  */
 415                 exthdrs.ip6e_dest2 = NULL;
 416
 417             {
 418                 struct ip6_rthdr *rh = NULL;
 419                 int segleft_org = 0;
 420                 struct ipsec_output_state state;
 421
 422                 if (exthdrs.ip6e_rthdr) {
 423                         rh = mtod(exthdrs.ip6e_rthdr, struct ip6_rthdr *);
 424                         segleft_org = rh->ip6r_segleft;
 425                         rh->ip6r_segleft = 0;
 426                 }
 427
 428                 bzero(&state, sizeof(state));
 429                 state.m = m;
 430                 error = ipsec6_output_trans(&state, nexthdrp, mprev, sp, flags,
 431                         &needipsectun);
 432                 m = state.m;
 433                 if (error) {
 434                         /* mbuf is already reclaimed in ipsec6_output_trans. */
 435                         m = NULL;
 436                         switch (error) {
 437                         case EHOSTUNREACH:
 438                         case ENETUNREACH:
 439                         case EMSGSIZE:
 440                         case ENOBUFS:
 441                         case ENOMEM:
 442                                 break;
 443                         default:
 444                                 printf("ip6_output (ipsec): error code %d\n", error);
 445                                 /* fall through */
 446                         case ENOENT:
 447                                 /* don't show these error codes to the user */
 448                                 error = 0;
 449                                 break;
 450                         }
 451                         goto bad;
 452                 }
 453                 if (exthdrs.ip6e_rthdr) {
 454                         /* ah6_output doesn't modify mbuf chain */
 455                         rh->ip6r_segleft = segleft_org;
 456                 }
 457             }
 458 skip_ipsec2:;
 459 #endif
 460         }
 461
 462         /*
 463          * If there is a routing header, replace destination address field
 464          * with the first hop of the routing header.
 465          */
 466         if (exthdrs.ip6e_rthdr) {
 467                 struct ip6_rthdr *rh =
 468                         (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr,
 469                                                   struct ip6_rthdr *));
 470                 struct ip6_rthdr0 *rh0;
 471
 472                 finaldst = ip6->ip6_dst;
 473                 switch (rh->ip6r_type) {
 474                 case IPV6_RTHDR_TYPE_0:
 475                          rh0 = (struct ip6_rthdr0 *)rh;
 476                          ip6->ip6_dst = rh0->ip6r0_addr[0];
 477                          bcopy((caddr_t)&rh0->ip6r0_addr[1],
 478                                (caddr_t)&rh0->ip6r0_addr[0],
 479                                sizeof(struct in6_addr)*(rh0->ip6r0_segleft - 1)
 480                                  );
 481                          rh0->ip6r0_addr[rh0->ip6r0_segleft - 1] = finaldst;
 482                          break;
 483                 default:        /* is it possible? */
 484                          error = EINVAL;
 485                          goto bad;
 486                 }
 487         }
 488
 489         /* Source address validation */
 490         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 491             (flags & IPV6_DADOUTPUT) == 0) {
 492                 error = EOPNOTSUPP;
 493                 ip6stat.ip6s_badscope++;
 494                 goto bad;
 495         }
 496         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 497                 error = EOPNOTSUPP;
 498                 ip6stat.ip6s_badscope++;
 499                 goto bad;
 500         }
 501
 502         ip6stat.ip6s_localout++;
 503
 504         /*
 505          * Route packet.
 506          */
 507         if (ro == 0) {
 508                 ro = &ip6route;
 509                 bzero((caddr_t)ro, sizeof(*ro));
 510         }
 511         ro_pmtu = ro;
 512         if (opt && opt->ip6po_rthdr)
 513                 ro = &opt->ip6po_route;
 514         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 515         /*
 516          * If there is a cached route,
 517          * check that it is to the same destination
 518          * and is still up. If not, free it and try again.
 519          */
 520         if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 521                          dst->sin6_family != AF_INET6 ||
 522                          !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_dst))) {
 523                 RTFREE(ro->ro_rt);
 524                 ro->ro_rt = (struct rtentry *)0;
 525         }
 526         if (ro->ro_rt == 0) {
 527                 bzero(dst, sizeof(*dst));
 528                 dst->sin6_family = AF_INET6;
 529                 dst->sin6_len = sizeof(struct sockaddr_in6);
 530                 dst->sin6_addr = ip6->ip6_dst;
 531 #ifdef SCOPEDROUTING
 532                 /* XXX: sin6_scope_id should already be fixed at this point */
 533                 if (IN6_IS_SCOPE_LINKLOCAL(&dst->sin6_addr))
 534                         dst->sin6_scope_id = ntohs(dst->sin6_addr.s6_addr16[1]);
 535 #endif
 536         }
 537 #if defined(IPSEC) || defined(FAST_IPSEC)
 538         if (needipsec && needipsectun) {
 539                 struct ipsec_output_state state;
 540
 541                 /*
 542                  * All the extension headers will become inaccessible
 543                  * (since they can be encrypted).
 544                  * Don't panic, we need no more updates to extension headers
 545                  * on inner IPv6 packet (since they are now encapsulated).
 546                  *
 547                  * IPv6 [ESP|AH] IPv6 [extension headers] payload
 548                  */
 549                 bzero(&exthdrs, sizeof(exthdrs));
 550                 exthdrs.ip6e_ip6 = m;
 551
 552                 bzero(&state, sizeof(state));
 553                 state.m = m;
 554                 state.ro = (struct route *)ro;
 555                 state.dst = (struct sockaddr *)dst;
 556
 557                 error = ipsec6_output_tunnel(&state, sp, flags);
 558
 559                 m = state.m;
 560                 ro = (struct route_in6 *)state.ro;
 561                 dst = (struct sockaddr_in6 *)state.dst;
 562                 if (error) {
 563                         /* mbuf is already reclaimed in ipsec6_output_tunnel. */
 564                         m0 = m = NULL;
 565                         m = NULL;
 566                         switch (error) {
 567                         case EHOSTUNREACH:
 568                         case ENETUNREACH:
 569                         case EMSGSIZE:
 570                         case ENOBUFS:
 571                         case ENOMEM:
 572                                 break;
 573                         default:
 574                                 printf("ip6_output (ipsec): error code %d\n", error);
 575                                 /* fall through */
 576                         case ENOENT:
 577                                 /* don't show these error codes to the user */
 578                                 error = 0;
 579                                 break;
 580                         }
 581                         goto bad;
 582                 }
 583
 584                 exthdrs.ip6e_ip6 = m;
 585         }
 586 #endif /* IPSEC */
 587
 588         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 589                 /* Unicast */
 590
 591 #define ifatoia6(ifa)   ((struct in6_ifaddr *)(ifa))
 592 #define sin6tosa(sin6)  ((struct sockaddr *)(sin6))
 593                 /* xxx
 594                  * interface selection comes here
 595                  * if an interface is specified from an upper layer,
 596                  * ifp must point it.
 597                  */
 598                 if (ro->ro_rt == 0) {
 599                         /*
 600                          * non-bsdi always clone routes, if parent is
 601                          * PRF_CLONING.
 602                          */
 603                         rtalloc((struct route *)ro);
 604                 }
 605                 if (ro->ro_rt == 0) {
 606                         ip6stat.ip6s_noroute++;
 607                         error = EHOSTUNREACH;
 608                         /* XXX in6_ifstat_inc(ifp, ifs6_out_discard); */
 609                         goto bad;
 610                 }
 611                 ia = ifatoia6(ro->ro_rt->rt_ifa);
 612                 ifp = ro->ro_rt->rt_ifp;
 613                 ro->ro_rt->rt_use++;
 614                 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
 615                         dst = (struct sockaddr_in6 *)ro->ro_rt->rt_gateway;
 616                 m->m_flags &= ~(M_BCAST | M_MCAST);     /* just in case */
 617
 618                 in6_ifstat_inc(ifp, ifs6_out_request);
 619
 620                 /*
 621                  * Check if the outgoing interface conflicts with
 622                  * the interface specified by ifi6_ifindex (if specified).
 623                  * Note that loopback interface is always okay.
 624                  * (this may happen when we are sending a packet to one of
 625                  *  our own addresses.)
 626                  */
 627                 if (opt && opt->ip6po_pktinfo
 628                  && opt->ip6po_pktinfo->ipi6_ifindex) {
 629                         if (!(ifp->if_flags & IFF_LOOPBACK)
 630                          && ifp->if_index != opt->ip6po_pktinfo->ipi6_ifindex) {
 631                                 ip6stat.ip6s_noroute++;
 632                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 633                                 error = EHOSTUNREACH;
 634                                 goto bad;
 635                         }
 636                 }
 637
 638                 if (opt && opt->ip6po_hlim != -1)
 639                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 640         } else {
 641                 /* Multicast */
 642                 struct  in6_multi *in6m;
 643
 644                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 645
 646                 /*
 647                  * See if the caller provided any multicast options
 648                  */
 649                 ifp = NULL;
 650                 if (im6o != NULL) {
 651                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 652                         if (im6o->im6o_multicast_ifp != NULL)
 653                                 ifp = im6o->im6o_multicast_ifp;
 654                 } else
 655                         ip6->ip6_hlim = ip6_defmcasthlim;
 656
 657                 /*
 658                  * See if the caller provided the outgoing interface
 659                  * as an ancillary data.
 660                  * Boundary check for ifindex is assumed to be already done.
 661                  */
 662                 if (opt && opt->ip6po_pktinfo && opt->ip6po_pktinfo->ipi6_ifindex)
 663                         ifp = ifindex2ifnet[opt->ip6po_pktinfo->ipi6_ifindex];
 664
 665                 /*
 666                  * If the destination is a node-local scope multicast,
 667                  * the packet should be loop-backed only.
 668                  */
 669                 if (IN6_IS_ADDR_MC_NODELOCAL(&ip6->ip6_dst)) {
 670                         /*
 671                          * If the outgoing interface is already specified,
 672                          * it should be a loopback interface.
 673                          */
 674                         if (ifp && (ifp->if_flags & IFF_LOOPBACK) == 0) {
 675                                 ip6stat.ip6s_badscope++;
 676                                 error = ENETUNREACH; /* XXX: better error? */
 677                                 /* XXX correct ifp? */
 678                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 679                                 goto bad;
 680                         } else {
 681                                 ifp = &loif[0];
 682                         }
 683                 }
 684
 685                 if (opt && opt->ip6po_hlim != -1)
 686                         ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 687
 688                 /*
 689                  * If caller did not provide an interface lookup a
 690                  * default in the routing table.  This is either a
 691                  * default for the speicfied group (i.e. a host
 692                  * route), or a multicast default (a route for the
 693                  * ``net'' ff00::/8).
 694                  */
 695                 if (ifp == NULL) {
 696                         if (ro->ro_rt == 0) {
 697                                 ro->ro_rt = rtalloc1((struct sockaddr *)
 698                                                 &ro->ro_dst, 0, 0UL);
 699                         }
 700                         if (ro->ro_rt == 0) {
 701                                 ip6stat.ip6s_noroute++;
 702                                 error = EHOSTUNREACH;
 703                                 /* XXX in6_ifstat_inc(ifp, ifs6_out_discard) */
 704                                 goto bad;
 705                         }
 706                         ia = ifatoia6(ro->ro_rt->rt_ifa);
 707                         ifp = ro->ro_rt->rt_ifp;
 708                         ro->ro_rt->rt_use++;
 709                 }
 710
 711                 if ((flags & IPV6_FORWARDING) == 0)
 712                         in6_ifstat_inc(ifp, ifs6_out_request);
 713                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 714
 715                 /*
 716                  * Confirm that the outgoing interface supports multicast.
 717                  */
 718                 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 719                         ip6stat.ip6s_noroute++;
 720                         in6_ifstat_inc(ifp, ifs6_out_discard);
 721                         error = ENETUNREACH;
 722                         goto bad;
 723                 }
 724                 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
 725                 if (in6m != NULL &&
 726                    (im6o == NULL || im6o->im6o_multicast_loop)) {
 727                         /*
 728                          * If we belong to the destination multicast group
 729                          * on the outgoing interface, and the caller did not
 730                          * forbid loopback, loop back a copy.
 731                          */
 732                         ip6_mloopback(ifp, m, dst);
 733                 } else {
 734                         /*
 735                          * If we are acting as a multicast router, perform
 736                          * multicast forwarding as if the packet had just
 737                          * arrived on the interface to which we are about
 738                          * to send.  The multicast forwarding function
 739                          * recursively calls this function, using the
 740                          * IPV6_FORWARDING flag to prevent infinite recursion.
 741                          *
 742                          * Multicasts that are looped back by ip6_mloopback(),
 743                          * above, will be forwarded by the ip6_input() routine,
 744                          * if necessary.
 745                          */
 746                         if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 747                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 748                                         m_freem(m);
 749                                         goto done;
 750                                 }
 751                         }
 752                 }
 753                 /*
 754                  * Multicasts with a hoplimit of zero may be looped back,
 755                  * above, but must not be transmitted on a network.
 756                  * Also, multicasts addressed to the loopback interface
 757                  * are not sent -- the above call to ip6_mloopback() will
 758                  * loop back a copy if this host actually belongs to the
 759                  * destination group on the loopback interface.
 760                  */
 761                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK)) {
 762                         m_freem(m);
 763                         goto done;
 764                 }
 765         }
 766
 767         /*
 768          * Fill the outgoing inteface to tell the upper layer
 769          * to increment per-interface statistics.
 770          */
 771         if (ifpp)
 772                 *ifpp = ifp;
 773
 774         /*
 775          * Determine path MTU.
 776          */
 777         if (ro_pmtu != ro) {
 778                 /* The first hop and the final destination may differ. */
 779                 struct sockaddr_in6 *sin6_fin =
 780                         (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
 781                 if (ro_pmtu->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 782                                        !IN6_ARE_ADDR_EQUAL(&sin6_fin->sin6_addr,
 783                                                            &finaldst))) {
 784                         RTFREE(ro_pmtu->ro_rt);
 785                         ro_pmtu->ro_rt = (struct rtentry *)0;
 786                 }
 787                 if (ro_pmtu->ro_rt == 0) {
 788                         bzero(sin6_fin, sizeof(*sin6_fin));
 789                         sin6_fin->sin6_family = AF_INET6;
 790                         sin6_fin->sin6_len = sizeof(struct sockaddr_in6);
 791                         sin6_fin->sin6_addr = finaldst;
 792
 793                         rtalloc((struct route *)ro_pmtu);
 794                 }
 795         }
 796         if (ro_pmtu->ro_rt != NULL) {
 797                 u_int32_t ifmtu = nd_ifinfo[ifp->if_index].linkmtu;
 798
 799                 mtu = ro_pmtu->ro_rt->rt_rmx.rmx_mtu;
 800                 if (mtu > ifmtu || mtu == 0) {
 801                         /*
 802                          * The MTU on the route is larger than the MTU on
 803                          * the interface!  This shouldn't happen, unless the
 804                          * MTU of the interface has been changed after the
 805                          * interface was brought up.  Change the MTU in the
 806                          * route to match the interface MTU (as long as the
 807                          * field isn't locked).
 808                          *
 809                          * if MTU on the route is 0, we need to fix the MTU.
 810                          * this case happens with path MTU discovery timeouts.
 811                          */
 812                          mtu = ifmtu;
 813                          if ((ro_pmtu->ro_rt->rt_rmx.rmx_locks & RTV_MTU) == 0)
 814                                  ro_pmtu->ro_rt->rt_rmx.rmx_mtu = mtu; /* XXX */
 815                 }
 816         } else {
 817                 mtu = nd_ifinfo[ifp->if_index].linkmtu;
 818         }
 819
 820         /*
 821          * advanced API (IPV6_USE_MIN_MTU) overrides mtu setting
 822          */
 823         if ((flags & IPV6_MINMTU) != 0 && mtu > IPV6_MMTU)
 824                 mtu = IPV6_MMTU;
 825
 826         /* Fake scoped addresses */
 827         if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
 828                 /*
 829                  * If source or destination address is a scoped address, and
 830                  * the packet is going to be sent to a loopback interface,
 831                  * we should keep the original interface.
 832                  */
 833
 834                 /*
 835                  * XXX: this is a very experimental and temporary solution.
 836                  * We eventually have sockaddr_in6 and use the sin6_scope_id
 837                  * field of the structure here.
 838                  * We rely on the consistency between two scope zone ids
 839                  * of source and destination, which should already be assured.
 840                  * Larger scopes than link will be supported in the future.
 841                  */
 842                 origifp = NULL;
 843                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
 844                         origifp = ifindex2ifnet[ntohs(ip6->ip6_src.s6_addr16[1])];
 845                 else if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
 846                         origifp = ifindex2ifnet[ntohs(ip6->ip6_dst.s6_addr16[1])];
 847                 /*
 848                  * XXX: origifp can be NULL even in those two cases above.
 849                  * For example, if we remove the (only) link-local address
 850                  * from the loopback interface, and try to send a link-local
 851                  * address without link-id information.  Then the source
 852                  * address is ::1, and the destination address is the
 853                  * link-local address with its s6_addr16[1] being zero.
 854                  * What is worse, if the packet goes to the loopback interface
 855                  * by a default rejected route, the null pointer would be
 856                  * passed to looutput, and the kernel would hang.
 857                  * The following last resort would prevent such disaster.
 858                  */
 859                 if (origifp == NULL)
 860                         origifp = ifp;
 861         }
 862         else
 863                 origifp = ifp;
 864 #ifndef SCOPEDROUTING
 865         /*
 866          * clear embedded scope identifiers if necessary.
 867          * in6_clearscope will touch the addresses only when necessary.
 868          */
 869         in6_clearscope(&ip6->ip6_src);
 870         in6_clearscope(&ip6->ip6_dst);
 871 #endif
 872
 873         /*
 874          * Check with the firewall...
 875          */
 876         if (ip6_fw_enable && ip6_fw_chk_ptr) {
 877                 u_short port = 0;
 878                 m->m_pkthdr.rcvif = NULL;       /* XXX */
 879                 /* If ipfw says divert, we have to just drop packet */
 880                 if ((*ip6_fw_chk_ptr)(&ip6, ifp, &port, &m)) {
 881                         m_freem(m);
 882                         goto done;
 883                 }
 884                 if (!m) {
 885                         error = EACCES;
 886                         goto done;
 887                 }
 888         }
 889
 890         /*
 891          * If the outgoing packet contains a hop-by-hop options header,
 892          * it must be examined and processed even by the source node.
 893          * (RFC 2460, section 4.)
 894          */
 895         if (exthdrs.ip6e_hbh) {
 896                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 897                 u_int32_t dummy1; /* XXX unused */
 898                 u_int32_t dummy2; /* XXX unused */
 899
 900 #ifdef DIAGNOSTIC
 901                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 902                         panic("ip6e_hbh is not continuous");
 903 #endif
 904                 /*
 905                  *  XXX: if we have to send an ICMPv6 error to the sender,
 906                  *       we need the M_LOOP flag since icmp6_error() expects
 907                  *       the IPv6 and the hop-by-hop options header are
 908                  *       continuous unless the flag is set.
 909                  */
 910                 m->m_flags |= M_LOOP;
 911                 m->m_pkthdr.rcvif = ifp;
 912                 if (ip6_process_hopopts(m,
 913                                         (u_int8_t *)(hbh + 1),
 914                                         ((hbh->ip6h_len + 1) << 3) -
 915                                         sizeof(struct ip6_hbh),
 916                                         &dummy1, &dummy2) < 0) {
 917                         /* m was already freed at this point */
 918                         error = EINVAL;/* better error? */
 919                         goto done;
 920                 }
 921                 m->m_flags &= ~M_LOOP; /* XXX */
 922                 m->m_pkthdr.rcvif = NULL;
 923         }
 924
 925 #ifdef PFIL_HOOKS
 926         /*
 927          * Run through list of hooks for output packets.
 928          */
 929         error = pfil_run_hooks(&inet6_pfil_hook, &m, ifp, PFIL_OUT);
 930         if (error != 0 || m == NULL)
 931                 goto done;
 932         ip6 = mtod(m, struct ip6_hdr *);
 933 #endif /* PFIL_HOOKS */
 934         /*
 935          * Send the packet to the outgoing interface.
 936          * If necessary, do IPv6 fragmentation before sending.
 937          */
 938         tlen = m->m_pkthdr.len;
 939         if (tlen <= mtu
 940 #ifdef notyet
 941             /*
 942              * On any link that cannot convey a 1280-octet packet in one piece,
 943              * link-specific fragmentation and reassembly must be provided at
 944              * a layer below IPv6. [RFC 2460, sec.5]
 945              * Thus if the interface has ability of link-level fragmentation,
 946              * we can just send the packet even if the packet size is
 947              * larger than the link's MTU.
 948              * XXX: IFF_FRAGMENTABLE (or such) flag has not been defined yet...
 949              */
 950
 951             || ifp->if_flags & IFF_FRAGMENTABLE
 952 #endif
 953             )
 954         {
 955                 /* Record statistics for this interface address. */
 956                 if (ia && !(flags & IPV6_FORWARDING)) {
 957                         ia->ia_ifa.if_opackets++;
 958                         ia->ia_ifa.if_obytes += m->m_pkthdr.len;
 959                 }
 960 #ifdef IPSEC
 961                 /* clean ipsec history once it goes out of the node */
 962                 ipsec_delaux(m);
 963 #endif
 964                 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
 965                 goto done;
 966         } else if (mtu < IPV6_MMTU) {
 967                 /*
 968                  * note that path MTU is never less than IPV6_MMTU
 969                  * (see icmp6_input).
 970                  */
 971                 error = EMSGSIZE;
 972                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 973                 goto bad;
 974         } else if (ip6->ip6_plen == 0) { /* jumbo payload cannot be fragmented */
 975                 error = EMSGSIZE;
 976                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 977                 goto bad;
 978         } else {
 979                 struct mbuf **mnext, *m_frgpart;
 980                 struct ip6_frag *ip6f;
 981                 u_int32_t id = htonl(ip6_id++);
 982                 u_char nextproto;
 983
 984                 /*
 985                  * Too large for the destination or interface;
 986                  * fragment if possible.
 987                  * Must be able to put at least 8 bytes per fragment.
 988                  */
 989                 hlen = unfragpartlen;
 990                 if (mtu > IPV6_MAXPACKET)
 991                         mtu = IPV6_MAXPACKET;
 992
 993                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
 994                 if (len < 8) {
 995                         error = EMSGSIZE;
 996                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
 997                         goto bad;
 998                 }
 999
1000                 mnext = &m->m_nextpkt;
1001
1002                 /*
1003                  * Change the next header field of the last header in the
1004                  * unfragmentable part.
1005                  */
1006                 if (exthdrs.ip6e_rthdr) {
1007                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1008                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1009                 } else if (exthdrs.ip6e_dest1) {
1010                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1011                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1012                 } else if (exthdrs.ip6e_hbh) {
1013                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1014                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1015                 } else {
1016                         nextproto = ip6->ip6_nxt;
1017                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1018                 }
1019
1020                 /*
1021                  * Loop through length of segment after first fragment,
1022                  * make new header and copy data of each part and link onto
1023                  * chain.
1024                  */
1025                 m0 = m;
1026                 for (off = hlen; off < tlen; off += len) {
1027                         MGETHDR(m, M_DONTWAIT, MT_HEADER);
1028                         if (!m) {
1029                                 error = ENOBUFS;
1030                                 ip6stat.ip6s_odropped++;
1031                                 goto sendorfree;
1032                         }
1033                         m->m_pkthdr.rcvif = NULL;
1034                         m->m_flags = m0->m_flags & M_COPYFLAGS;
1035                         *mnext = m;
1036                         mnext = &m->m_nextpkt;
1037                         m->m_data += max_linkhdr;
1038                         mhip6 = mtod(m, struct ip6_hdr *);
1039                         *mhip6 = *ip6;
1040                         m->m_len = sizeof(*mhip6);
1041                         error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
1042                         if (error) {
1043                                 ip6stat.ip6s_odropped++;
1044                                 goto sendorfree;
1045                         }
1046                         ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
1047                         if (off + len >= tlen)
1048                                 len = tlen - off;
1049                         else
1050                                 ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
1051                         mhip6->ip6_plen = htons((u_short)(len + hlen +
1052                                                           sizeof(*ip6f) -
1053                                                           sizeof(struct ip6_hdr)));
1054                         if ((m_frgpart = m_copy(m0, off, len)) == 0) {
1055                                 error = ENOBUFS;
1056                                 ip6stat.ip6s_odropped++;
1057                                 goto sendorfree;
1058                         }
1059                         m_cat(m, m_frgpart);
1060                         m->m_pkthdr.len = len + hlen + sizeof(*ip6f);
1061                         m->m_pkthdr.rcvif = (struct ifnet *)0;
1062                         ip6f->ip6f_reserved = 0;
1063                         ip6f->ip6f_ident = id;
1064                         ip6f->ip6f_nxt = nextproto;
1065                         ip6stat.ip6s_ofragments++;
1066                         in6_ifstat_inc(ifp, ifs6_out_fragcreat);
1067                 }
1068
1069                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1070         }
1071
1072         /*
1073          * Remove leading garbages.
1074          */
1075 sendorfree:
1076         m = m0->m_nextpkt;
1077         m0->m_nextpkt = 0;
1078         m_freem(m0);
1079         for (m0 = m; m; m = m0) {
1080                 m0 = m->m_nextpkt;
1081                 m->m_nextpkt = 0;
1082                 if (error == 0) {
1083                         /* Record statistics for this interface address. */
1084                         if (ia) {
1085                                 ia->ia_ifa.if_opackets++;
1086                                 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1087                         }
1088 #ifdef IPSEC
1089                         /* clean ipsec history once it goes out of the node */
1090                         ipsec_delaux(m);
1091 #endif
1092                         error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
1093                 } else
1094                         m_freem(m);
1095         }
1096
1097         if (error == 0)
1098                 ip6stat.ip6s_fragmented++;
1099
1100 done:
1101         if (ro == &ip6route && ro->ro_rt) { /* brace necessary for RTFREE */
1102                 RTFREE(ro->ro_rt);
1103         } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) {
1104                 RTFREE(ro_pmtu->ro_rt);
1105         }
1106
1107 #ifdef IPSEC
1108         if (sp != NULL)
1109                 key_freesp(sp);
1110 #endif /* IPSEC */
1111 #ifdef FAST_IPSEC
1112         if (sp != NULL)
1113                 KEY_FREESP(&sp);
1114 #endif /* FAST_IPSEC */
1115
1116         return(error);
1117
1118 freehdrs:
1119         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1120         m_freem(exthdrs.ip6e_dest1);
1121         m_freem(exthdrs.ip6e_rthdr);
1122         m_freem(exthdrs.ip6e_dest2);
1123         /* fall through */
1124 bad:
1125         m_freem(m);
1126         goto done;
1127 }
1128
1129 static int
1130 ip6_copyexthdr(mp, hdr, hlen)
1131         struct mbuf **mp;
1132         caddr_t hdr;
1133         int hlen;
1134 {
1135         struct mbuf *m;
1136
1137         if (hlen > MCLBYTES)
1138                 return(ENOBUFS); /* XXX */
1139
1140         MGET(m, M_DONTWAIT, MT_DATA);
1141         if (!m)
1142                 return(ENOBUFS);
1143
1144         if (hlen > MLEN) {
1145                 MCLGET(m, M_DONTWAIT);
1146                 if ((m->m_flags & M_EXT) == 0) {
1147                         m_free(m);
1148                         return(ENOBUFS);
1149                 }
1150         }
1151         m->m_len = hlen;
1152         if (hdr)
1153                 bcopy(hdr, mtod(m, caddr_t), hlen);
1154
1155         *mp = m;
1156         return(0);
1157 }
1158
1159 /*
1160  * Insert jumbo payload option.
1161  */
1162 static int
1163 ip6_insert_jumboopt(exthdrs, plen)
1164         struct ip6_exthdrs *exthdrs;
1165         u_int32_t plen;
1166 {
1167         struct mbuf *mopt;
1168         u_char *optbuf;
1169         u_int32_t v;
1170
1171 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1172
1173         /*
1174          * If there is no hop-by-hop options header, allocate new one.
1175          * If there is one but it doesn't have enough space to store the
1176          * jumbo payload option, allocate a cluster to store the whole options.
1177          * Otherwise, use it to store the options.
1178          */
1179         if (exthdrs->ip6e_hbh == 0) {
1180                 MGET(mopt, M_DONTWAIT, MT_DATA);
1181                 if (mopt == 0)
1182                         return(ENOBUFS);
1183                 mopt->m_len = JUMBOOPTLEN;
1184                 optbuf = mtod(mopt, u_char *);
1185                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1186                 exthdrs->ip6e_hbh = mopt;
1187         } else {
1188                 struct ip6_hbh *hbh;
1189
1190                 mopt = exthdrs->ip6e_hbh;
1191                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1192                         /*
1193                          * XXX assumption:
1194                          * - exthdrs->ip6e_hbh is not referenced from places
1195                          *   other than exthdrs.
1196                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1197                          */
1198                         int oldoptlen = mopt->m_len;
1199                         struct mbuf *n;
1200
1201                         /*
1202                          * XXX: give up if the whole (new) hbh header does
1203                          * not fit even in an mbuf cluster.
1204                          */
1205                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1206                                 return(ENOBUFS);
1207
1208                         /*
1209                          * As a consequence, we must always prepare a cluster
1210                          * at this point.
1211                          */
1212                         MGET(n, M_DONTWAIT, MT_DATA);
1213                         if (n) {
1214                                 MCLGET(n, M_DONTWAIT);
1215                                 if ((n->m_flags & M_EXT) == 0) {
1216                                         m_freem(n);
1217                                         n = NULL;
1218                                 }
1219                         }
1220                         if (!n)
1221                                 return(ENOBUFS);
1222                         n->m_len = oldoptlen + JUMBOOPTLEN;
1223                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1224                               oldoptlen);
1225                         optbuf = mtod(n, caddr_t) + oldoptlen;
1226                         m_freem(mopt);
1227                         mopt = exthdrs->ip6e_hbh = n;
1228                 } else {
1229                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1230                         mopt->m_len += JUMBOOPTLEN;
1231                 }
1232                 optbuf[0] = IP6OPT_PADN;
1233                 optbuf[1] = 1;
1234
1235                 /*
1236                  * Adjust the header length according to the pad and
1237                  * the jumbo payload option.
1238                  */
1239                 hbh = mtod(mopt, struct ip6_hbh *);
1240                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1241         }
1242
1243         /* fill in the option. */
1244         optbuf[2] = IP6OPT_JUMBO;
1245         optbuf[3] = 4;
1246         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1247         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1248
1249         /* finally, adjust the packet header length */
1250         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1251
1252         return(0);
1253 #undef JUMBOOPTLEN
1254 }
1255
1256 /*
1257  * Insert fragment header and copy unfragmentable header portions.
1258  */
1259 static int
1260 ip6_insertfraghdr(m0, m, hlen, frghdrp)
1261         struct mbuf *m0, *m;
1262         int hlen;
1263         struct ip6_frag **frghdrp;
1264 {
1265         struct mbuf *n, *mlast;
1266
1267         if (hlen > sizeof(struct ip6_hdr)) {
1268                 n = m_copym(m0, sizeof(struct ip6_hdr),
1269                             hlen - sizeof(struct ip6_hdr), M_DONTWAIT);
1270                 if (n == 0)
1271                         return(ENOBUFS);
1272                 m->m_next = n;
1273         } else
1274                 n = m;
1275
1276         /* Search for the last mbuf of unfragmentable part. */
1277         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1278                 ;
1279
1280         if ((mlast->m_flags & M_EXT) == 0 &&
1281             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1282                 /* use the trailing space of the last mbuf for the fragment hdr */
1283                 *frghdrp =
1284                         (struct ip6_frag *)(mtod(mlast, caddr_t) + mlast->m_len);
1285                 mlast->m_len += sizeof(struct ip6_frag);
1286                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1287         } else {
1288                 /* allocate a new mbuf for the fragment header */
1289                 struct mbuf *mfrg;
1290
1291                 MGET(mfrg, M_DONTWAIT, MT_DATA);
1292                 if (mfrg == 0)
1293                         return(ENOBUFS);
1294                 mfrg->m_len = sizeof(struct ip6_frag);
1295                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1296                 mlast->m_next = mfrg;
1297         }
1298
1299         return(0);
1300 }
1301
1302 /*
1303  * IP6 socket option processing.
1304  */
1305 int
1306 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1307 {
1308         int privileged;
1309         struct inpcb *in6p = sotoinpcb(so);
1310         int error, optval;
1311         int level, op, optname;
1312         int optlen;
1313         struct thread *td;
1314
1315         if (sopt) {
1316                 level = sopt->sopt_level;
1317                 op = sopt->sopt_dir;
1318                 optname = sopt->sopt_name;
1319                 optlen = sopt->sopt_valsize;
1320                 td = sopt->sopt_td;
1321         } else {
1322                 panic("ip6_ctloutput: arg soopt is NULL");
1323                 /* NOT REACHED */
1324                 td = NULL;
1325         }
1326         error = optval = 0;
1327
1328         privileged = (td == NULL || suser(td)) ? 0 : 1;
1329
1330         if (level == IPPROTO_IPV6) {
1331                 switch (op) {
1332
1333                 case SOPT_SET:
1334                         switch (optname) {
1335                         case IPV6_PKTOPTIONS:
1336                         {
1337                                 struct mbuf *m;
1338
1339                                 error = soopt_getm(sopt, &m); /* XXX */
1340                                 if (error != NULL)
1341                                         break;
1342                                 error = soopt_mcopyin(sopt, m); /* XXX */
1343                                 if (error != NULL)
1344                                         break;
1345                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1346                                                     m, so, sopt);
1347                                 m_freem(m); /* XXX */
1348                                 break;
1349                         }
1350
1351                         /*
1352                          * Use of some Hop-by-Hop options or some
1353                          * Destination options, might require special
1354                          * privilege.  That is, normal applications
1355                          * (without special privilege) might be forbidden
1356                          * from setting certain options in outgoing packets,
1357                          * and might never see certain options in received
1358                          * packets. [RFC 2292 Section 6]
1359                          * KAME specific note:
1360                          *  KAME prevents non-privileged users from sending or
1361                          *  receiving ANY hbh/dst options in order to avoid
1362                          *  overhead of parsing options in the kernel.
1363                          */
1364                         case IPV6_UNICAST_HOPS:
1365                         case IPV6_CHECKSUM:
1366                         case IPV6_FAITH:
1367
1368                         case IPV6_V6ONLY:
1369                                 if (optlen != sizeof(int)) {
1370                                         error = EINVAL;
1371                                         break;
1372                                 }
1373                                 error = sooptcopyin(sopt, &optval,
1374                                         sizeof optval, sizeof optval);
1375                                 if (error)
1376                                         break;
1377                                 switch (optname) {
1378
1379                                 case IPV6_UNICAST_HOPS:
1380                                         if (optval < -1 || optval >= 256)
1381                                                 error = EINVAL;
1382                                         else {
1383                                                 /* -1 = kernel default */
1384                                                 in6p->in6p_hops = optval;
1385
1386                                                 if ((in6p->in6p_vflag &
1387                                                      INP_IPV4) != 0)
1388                                                         in6p->inp_ip_ttl = optval;
1389                                         }
1390                                         break;
1391 #define OPTSET(bit) \
1392 do { \
1393         if (optval) \
1394                 in6p->in6p_flags |= (bit); \
1395         else \
1396                 in6p->in6p_flags &= ~(bit); \
1397 } while (0)
1398 #define OPTBIT(bit) (in6p->in6p_flags & (bit) ? 1 : 0)
1399
1400                                 case IPV6_CHECKSUM:
1401                                         in6p->in6p_cksum = optval;
1402                                         break;
1403
1404                                 case IPV6_FAITH:
1405                                         OPTSET(IN6P_FAITH);
1406                                         break;
1407
1408                                 case IPV6_V6ONLY:
1409                                         /*
1410                                          * make setsockopt(IPV6_V6ONLY)
1411                                          * available only prior to bind(2).
1412                                          * see ipng mailing list, Jun 22 2001.
1413                                          */
1414                                         if (in6p->in6p_lport ||
1415                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr))
1416                                         {
1417                                                 error = EINVAL;
1418                                                 break;
1419                                         }
1420                                         OPTSET(IN6P_IPV6_V6ONLY);
1421                                         if (optval)
1422                                                 in6p->in6p_vflag &= ~INP_IPV4;
1423                                         else
1424                                                 in6p->in6p_vflag |= INP_IPV4;
1425                                         break;
1426                                 }
1427                                 break;
1428
1429                         case IPV6_PKTINFO:
1430                         case IPV6_HOPLIMIT:
1431                         case IPV6_HOPOPTS:
1432                         case IPV6_DSTOPTS:
1433                         case IPV6_RTHDR:
1434                                 /* RFC 2292 */
1435                                 if (optlen != sizeof(int)) {
1436                                         error = EINVAL;
1437                                         break;
1438                                 }
1439                                 error = sooptcopyin(sopt, &optval,
1440                                         sizeof optval, sizeof optval);
1441                                 if (error)
1442                                         break;
1443                                 switch (optname) {
1444                                 case IPV6_PKTINFO:
1445                                         OPTSET(IN6P_PKTINFO);
1446                                         break;
1447                                 case IPV6_HOPLIMIT:
1448                                         OPTSET(IN6P_HOPLIMIT);
1449                                         break;
1450                                 case IPV6_HOPOPTS:
1451                                         /*
1452                                          * Check super-user privilege.
1453                                          * See comments for IPV6_RECVHOPOPTS.
1454                                          */
1455                                         if (!privileged)
1456                                                 return(EPERM);
1457                                         OPTSET(IN6P_HOPOPTS);
1458                                         break;
1459                                 case IPV6_DSTOPTS:
1460                                         if (!privileged)
1461                                                 return(EPERM);
1462                                         OPTSET(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1463                                         break;
1464                                 case IPV6_RTHDR:
1465                                         OPTSET(IN6P_RTHDR);
1466                                         break;
1467                                 }
1468                                 break;
1469 #undef OPTSET
1470
1471                         case IPV6_MULTICAST_IF:
1472                         case IPV6_MULTICAST_HOPS:
1473                         case IPV6_MULTICAST_LOOP:
1474                         case IPV6_JOIN_GROUP:
1475                         case IPV6_LEAVE_GROUP:
1476                             {
1477                                 struct mbuf *m;
1478                                 if (sopt->sopt_valsize > MLEN) {
1479                                         error = EMSGSIZE;
1480                                         break;
1481                                 }
1482                                 /* XXX */
1483                                 MGET(m, sopt->sopt_td ? M_WAIT : M_DONTWAIT, MT_HEADER);
1484                                 if (m == 0) {
1485                                         error = ENOBUFS;
1486                                         break;
1487                                 }
1488                                 m->m_len = sopt->sopt_valsize;
1489                                 error = sooptcopyin(sopt, mtod(m, char *),
1490                                                     m->m_len, m->m_len);
1491                                 error = ip6_setmoptions(sopt->sopt_name,
1492                                                         &in6p->in6p_moptions,
1493                                                         m);
1494                                 (void)m_free(m);
1495                             }
1496                                 break;
1497
1498                         case IPV6_PORTRANGE:
1499                                 error = sooptcopyin(sopt, &optval,
1500                                     sizeof optval, sizeof optval);
1501                                 if (error)
1502                                         break;
1503
1504                                 switch (optval) {
1505                                 case IPV6_PORTRANGE_DEFAULT:
1506                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1507                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1508                                         break;
1509
1510                                 case IPV6_PORTRANGE_HIGH:
1511                                         in6p->in6p_flags &= ~(IN6P_LOWPORT);
1512                                         in6p->in6p_flags |= IN6P_HIGHPORT;
1513                                         break;
1514
1515                                 case IPV6_PORTRANGE_LOW:
1516                                         in6p->in6p_flags &= ~(IN6P_HIGHPORT);
1517                                         in6p->in6p_flags |= IN6P_LOWPORT;
1518                                         break;
1519
1520                                 default:
1521                                         error = EINVAL;
1522                                         break;
1523                                 }
1524                                 break;
1525
1526 #if defined(IPSEC) || defined(FAST_IPSEC)
1527                         case IPV6_IPSEC_POLICY:
1528                             {
1529                                 caddr_t req = NULL;
1530                                 size_t len = 0;
1531                                 struct mbuf *m;
1532
1533                                 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1534                                         break;
1535                                 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1536                                         break;
1537                                 if (m) {
1538                                         req = mtod(m, caddr_t);
1539                                         len = m->m_len;
1540                                 }
1541                                 error = ipsec6_set_policy(in6p, optname, req,
1542                                                           len, privileged);
1543                                 m_freem(m);
1544                             }
1545                                 break;
1546 #endif /* KAME IPSEC */
1547
1548                         case IPV6_FW_ADD:
1549                         case IPV6_FW_DEL:
1550                         case IPV6_FW_FLUSH:
1551                         case IPV6_FW_ZERO:
1552                             {
1553                                 struct mbuf *m;
1554                                 struct mbuf **mp = &m;
1555
1556                                 if (ip6_fw_ctl_ptr == NULL)
1557                                         return EINVAL;
1558                                 /* XXX */
1559                                 if ((error = soopt_getm(sopt, &m)) != 0)
1560                                         break;
1561                                 /* XXX */
1562                                 if ((error = soopt_mcopyin(sopt, m)) != 0)
1563                                         break;
1564                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
1565                                 m = *mp;
1566                             }
1567                                 break;
1568
1569                         default:
1570                                 error = ENOPROTOOPT;
1571                                 break;
1572                         }
1573                         break;
1574
1575                 case SOPT_GET:
1576                         switch (optname) {
1577
1578                         case IPV6_PKTOPTIONS:
1579                                 if (in6p->in6p_options) {
1580                                         struct mbuf *m;
1581                                         m = m_copym(in6p->in6p_options,
1582                                             0, M_COPYALL, M_WAIT);
1583                                         error = soopt_mcopyout(sopt, m);
1584                                         if (error == 0)
1585                                                 m_freem(m);
1586                                 } else
1587                                         sopt->sopt_valsize = 0;
1588                                 break;
1589
1590                         case IPV6_UNICAST_HOPS:
1591                         case IPV6_CHECKSUM:
1592
1593                         case IPV6_FAITH:
1594                         case IPV6_V6ONLY:
1595                         case IPV6_PORTRANGE:
1596                                 switch (optname) {
1597
1598                                 case IPV6_UNICAST_HOPS:
1599                                         optval = in6p->in6p_hops;
1600                                         break;
1601
1602                                 case IPV6_CHECKSUM:
1603                                         optval = in6p->in6p_cksum;
1604                                         break;
1605
1606                                 case IPV6_FAITH:
1607                                         optval = OPTBIT(IN6P_FAITH);
1608                                         break;
1609
1610                                 case IPV6_V6ONLY:
1611                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
1612                                         break;
1613
1614                                 case IPV6_PORTRANGE:
1615                                     {
1616                                         int flags;
1617                                         flags = in6p->in6p_flags;
1618                                         if (flags & IN6P_HIGHPORT)
1619                                                 optval = IPV6_PORTRANGE_HIGH;
1620                                         else if (flags & IN6P_LOWPORT)
1621                                                 optval = IPV6_PORTRANGE_LOW;
1622                                         else
1623                                                 optval = 0;
1624                                         break;
1625                                     }
1626                                 }
1627                                 error = sooptcopyout(sopt, &optval,
1628                                         sizeof optval);
1629                                 break;
1630
1631                         case IPV6_PKTINFO:
1632                         case IPV6_HOPLIMIT:
1633                         case IPV6_HOPOPTS:
1634                         case IPV6_RTHDR:
1635                         case IPV6_DSTOPTS:
1636                                 if (optname == IPV6_HOPOPTS ||
1637                                     optname == IPV6_DSTOPTS ||
1638                                     !privileged)
1639                                         return(EPERM);
1640                                 switch (optname) {
1641                                 case IPV6_PKTINFO:
1642                                         optval = OPTBIT(IN6P_PKTINFO);
1643                                         break;
1644                                 case IPV6_HOPLIMIT:
1645                                         optval = OPTBIT(IN6P_HOPLIMIT);
1646                                         break;
1647                                 case IPV6_HOPOPTS:
1648                                         if (!privileged)
1649                                                 return(EPERM);
1650                                         optval = OPTBIT(IN6P_HOPOPTS);
1651                                         break;
1652                                 case IPV6_RTHDR:
1653                                         optval = OPTBIT(IN6P_RTHDR);
1654                                         break;
1655                                 case IPV6_DSTOPTS:
1656                                         if (!privileged)
1657                                                 return(EPERM);
1658                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
1659                                         break;
1660                                 }
1661                                 error = sooptcopyout(sopt, &optval,
1662                                         sizeof optval);
1663                                 break;
1664
1665                         case IPV6_MULTICAST_IF:
1666                         case IPV6_MULTICAST_HOPS:
1667                         case IPV6_MULTICAST_LOOP:
1668                         case IPV6_JOIN_GROUP:
1669                         case IPV6_LEAVE_GROUP:
1670                             {
1671                                 struct mbuf *m;
1672                                 error = ip6_getmoptions(sopt->sopt_name,
1673                                                 in6p->in6p_moptions, &m);
1674                                 if (error == 0)
1675                                         error = sooptcopyout(sopt,
1676                                                 mtod(m, char *), m->m_len);
1677                                 m_freem(m);
1678                             }
1679                                 break;
1680
1681 #if defined(IPSEC) || defined(FAST_IPSEC)
1682                         case IPV6_IPSEC_POLICY:
1683                           {
1684                                 caddr_t req = NULL;
1685                                 size_t len = 0;
1686                                 struct mbuf *m = NULL;
1687                                 struct mbuf **mp = &m;
1688
1689                                 error = soopt_getm(sopt, &m); /* XXX */
1690                                 if (error != NULL)
1691                                         break;
1692                                 error = soopt_mcopyin(sopt, m); /* XXX */
1693                                 if (error != NULL)
1694                                         break;
1695                                 if (m) {
1696                                         req = mtod(m, caddr_t);
1697                                         len = m->m_len;
1698                                 }
1699                                 error = ipsec6_get_policy(in6p, req, len, mp);
1700                                 if (error == 0)
1701                                         error = soopt_mcopyout(sopt, m); /*XXX*/
1702                                 if (error == 0 && m)
1703                                         m_freem(m);
1704                                 break;
1705                           }
1706 #endif /* KAME IPSEC */
1707
1708                         case IPV6_FW_GET:
1709                           {
1710                                 struct mbuf *m;
1711                                 struct mbuf **mp = &m;
1712
1713                                 if (ip6_fw_ctl_ptr == NULL)
1714                                 {
1715                                         return EINVAL;
1716                                 }
1717                                 error = (*ip6_fw_ctl_ptr)(optname, mp);
1718                                 if (error == 0)
1719                                         error = soopt_mcopyout(sopt, m); /* XXX */
1720                                 if (error == 0 && m)
1721                                         m_freem(m);
1722                           }
1723                                 break;
1724
1725                         default:
1726                                 error = ENOPROTOOPT;
1727                                 break;
1728                         }
1729                         break;
1730                 }
1731         } else {
1732                 error = EINVAL;
1733         }
1734         return(error);
1735 }
1736
1737 /*
1738  * Set up IP6 options in pcb for insertion in output packets or
1739  * specifying behavior of outgoing packets.
1740  */
1741 static int
1742 ip6_pcbopts(pktopt, m, so, sopt)
1743         struct ip6_pktopts **pktopt;
1744         struct mbuf *m;
1745         struct socket *so;
1746         struct sockopt *sopt;
1747 {
1748         struct ip6_pktopts *opt = *pktopt;
1749         int error = 0;
1750         struct thread *td = sopt->sopt_td;
1751         int priv = 0;
1752
1753         /* turn off any old options. */
1754         if (opt) {
1755 #ifdef DIAGNOSTIC
1756                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
1757                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
1758                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
1759                         printf("ip6_pcbopts: all specified options are cleared.\n");
1760 #endif
1761                 ip6_clearpktopts(opt, 1, -1);
1762         } else
1763                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
1764         *pktopt = NULL;
1765
1766         if (!m || m->m_len == 0) {
1767                 /*
1768                  * Only turning off any previous options, regardless of
1769                  * whether the opt is just created or given.
1770                  */
1771                 free(opt, M_IP6OPT);
1772                 return(0);
1773         }
1774
1775         /*  set options specified by user. */
1776         if (suser(td) == 0)
1777                 priv = 1;
1778         if ((error = ip6_setpktoptions(m, opt, priv, 1)) != 0) {
1779                 ip6_clearpktopts(opt, 1, -1); /* XXX: discard all options */
1780                 free(opt, M_IP6OPT);
1781                 return(error);
1782         }
1783         *pktopt = opt;
1784         return(0);
1785 }
1786
1787 /*
1788  * initialize ip6_pktopts.  beware that there are non-zero default values in
1789  * the struct.
1790  */
1791 void
1792 init_ip6pktopts(opt)
1793         struct ip6_pktopts *opt;
1794 {
1795
1796         bzero(opt, sizeof(*opt));
1797         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
1798 }
1799
1800 void
1801 ip6_clearpktopts(pktopt, needfree, optname)
1802         struct ip6_pktopts *pktopt;
1803         int needfree, optname;
1804 {
1805         if (pktopt == NULL)
1806                 return;
1807
1808         if (optname == -1) {
1809                 if (needfree && pktopt->ip6po_pktinfo)
1810                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
1811                 pktopt->ip6po_pktinfo = NULL;
1812         }
1813         if (optname == -1)
1814                 pktopt->ip6po_hlim = -1;
1815         if (optname == -1) {
1816                 if (needfree && pktopt->ip6po_nexthop)
1817                         free(pktopt->ip6po_nexthop, M_IP6OPT);
1818                 pktopt->ip6po_nexthop = NULL;
1819         }
1820         if (optname == -1) {
1821                 if (needfree && pktopt->ip6po_hbh)
1822                         free(pktopt->ip6po_hbh, M_IP6OPT);
1823                 pktopt->ip6po_hbh = NULL;
1824         }
1825         if (optname == -1) {
1826                 if (needfree && pktopt->ip6po_dest1)
1827                         free(pktopt->ip6po_dest1, M_IP6OPT);
1828                 pktopt->ip6po_dest1 = NULL;
1829         }
1830         if (optname == -1) {
1831                 if (needfree && pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
1832                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
1833                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
1834                 if (pktopt->ip6po_route.ro_rt) {
1835                         RTFREE(pktopt->ip6po_route.ro_rt);
1836                         pktopt->ip6po_route.ro_rt = NULL;
1837                 }
1838         }
1839         if (optname == -1) {
1840                 if (needfree && pktopt->ip6po_dest2)
1841                         free(pktopt->ip6po_dest2, M_IP6OPT);
1842                 pktopt->ip6po_dest2 = NULL;
1843         }
1844 }
1845
1846 #define PKTOPT_EXTHDRCPY(type) \
1847 do {\
1848         if (src->type) {\
1849                 int hlen =\
1850                         (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
1851                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
1852                 if (dst->type == NULL && canwait == M_NOWAIT)\
1853                         goto bad;\
1854                 bcopy(src->type, dst->type, hlen);\
1855         }\
1856 } while (0)
1857
1858 struct ip6_pktopts *
1859 ip6_copypktopts(src, canwait)
1860         struct ip6_pktopts *src;
1861         int canwait;
1862 {
1863         struct ip6_pktopts *dst;
1864
1865         if (src == NULL) {
1866                 printf("ip6_clearpktopts: invalid argument\n");
1867                 return(NULL);
1868         }
1869
1870         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
1871         if (dst == NULL && canwait == M_NOWAIT)
1872                 return (NULL);
1873         bzero(dst, sizeof(*dst));
1874
1875         dst->ip6po_hlim = src->ip6po_hlim;
1876         if (src->ip6po_pktinfo) {
1877                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
1878                                             M_IP6OPT, canwait);
1879                 if (dst->ip6po_pktinfo == NULL && canwait == M_NOWAIT)
1880                         goto bad;
1881                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
1882         }
1883         if (src->ip6po_nexthop) {
1884                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
1885                                             M_IP6OPT, canwait);
1886                 if (dst->ip6po_nexthop == NULL && canwait == M_NOWAIT)
1887                         goto bad;
1888                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
1889                       src->ip6po_nexthop->sa_len);
1890         }
1891         PKTOPT_EXTHDRCPY(ip6po_hbh);
1892         PKTOPT_EXTHDRCPY(ip6po_dest1);
1893         PKTOPT_EXTHDRCPY(ip6po_dest2);
1894         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
1895         return(dst);
1896
1897   bad:
1898         if (dst->ip6po_pktinfo) free(dst->ip6po_pktinfo, M_IP6OPT);
1899         if (dst->ip6po_nexthop) free(dst->ip6po_nexthop, M_IP6OPT);
1900         if (dst->ip6po_hbh) free(dst->ip6po_hbh, M_IP6OPT);
1901         if (dst->ip6po_dest1) free(dst->ip6po_dest1, M_IP6OPT);
1902         if (dst->ip6po_dest2) free(dst->ip6po_dest2, M_IP6OPT);
1903         if (dst->ip6po_rthdr) free(dst->ip6po_rthdr, M_IP6OPT);
1904         free(dst, M_IP6OPT);
1905         return(NULL);
1906 }
1907 #undef PKTOPT_EXTHDRCPY
1908
1909 void
1910 ip6_freepcbopts(pktopt)
1911         struct ip6_pktopts *pktopt;
1912 {
1913         if (pktopt == NULL)
1914                 return;
1915
1916         ip6_clearpktopts(pktopt, 1, -1);
1917
1918         free(pktopt, M_IP6OPT);
1919 }
1920
1921 /*
1922  * Set the IP6 multicast options in response to user setsockopt().
1923  */
1924 static int
1925 ip6_setmoptions(optname, im6op, m)
1926         int optname;
1927         struct ip6_moptions **im6op;
1928         struct mbuf *m;
1929 {
1930         int error = 0;
1931         u_int loop, ifindex;
1932         struct ipv6_mreq *mreq;
1933         struct ifnet *ifp;
1934         struct ip6_moptions *im6o = *im6op;
1935         struct route_in6 ro;
1936         struct sockaddr_in6 *dst;
1937         struct in6_multi_mship *imm;
1938         struct thread *td = curthread;  /* XXX */
1939
1940         if (im6o == NULL) {
1941                 /*
1942                  * No multicast option buffer attached to the pcb;
1943                  * allocate one and initialize to default values.
1944                  */
1945                 im6o = (struct ip6_moptions *)
1946                         malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK);
1947
1948                 if (im6o == NULL)
1949                         return(ENOBUFS);
1950                 *im6op = im6o;
1951                 im6o->im6o_multicast_ifp = NULL;
1952                 im6o->im6o_multicast_hlim = ip6_defmcasthlim;
1953                 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP;
1954                 LIST_INIT(&im6o->im6o_memberships);
1955         }
1956
1957         switch (optname) {
1958
1959         case IPV6_MULTICAST_IF:
1960                 /*
1961                  * Select the interface for outgoing multicast packets.
1962                  */
1963                 if (m == NULL || m->m_len != sizeof(u_int)) {
1964                         error = EINVAL;
1965                         break;
1966                 }
1967                 bcopy(mtod(m, u_int *), &ifindex, sizeof(ifindex));
1968                 if (ifindex < 0 || if_index < ifindex) {
1969                         error = ENXIO;  /* XXX EINVAL? */
1970                         break;
1971                 }
1972                 ifp = ifindex2ifnet[ifindex];
1973                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
1974                         error = EADDRNOTAVAIL;
1975                         break;
1976                 }
1977                 im6o->im6o_multicast_ifp = ifp;
1978                 break;
1979
1980         case IPV6_MULTICAST_HOPS:
1981             {
1982                 /*
1983                  * Set the IP6 hoplimit for outgoing multicast packets.
1984                  */
1985                 int optval;
1986                 if (m == NULL || m->m_len != sizeof(int)) {
1987                         error = EINVAL;
1988                         break;
1989                 }
1990                 bcopy(mtod(m, u_int *), &optval, sizeof(optval));
1991                 if (optval < -1 || optval >= 256)
1992                         error = EINVAL;
1993                 else if (optval == -1)
1994                         im6o->im6o_multicast_hlim = ip6_defmcasthlim;
1995                 else
1996                         im6o->im6o_multicast_hlim = optval;
1997                 break;
1998             }
1999
2000         case IPV6_MULTICAST_LOOP:
2001                 /*
2002                  * Set the loopback flag for outgoing multicast packets.
2003                  * Must be zero or one.
2004                  */
2005                 if (m == NULL || m->m_len != sizeof(u_int)) {
2006                         error = EINVAL;
2007                         break;
2008                 }
2009                 bcopy(mtod(m, u_int *), &loop, sizeof(loop));
2010                 if (loop > 1) {
2011                         error = EINVAL;
2012                         break;
2013                 }
2014                 im6o->im6o_multicast_loop = loop;
2015                 break;
2016
2017         case IPV6_JOIN_GROUP:
2018                 /*
2019                  * Add a multicast group membership.
2020                  * Group must be a valid IP6 multicast address.
2021                  */
2022                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2023                         error = EINVAL;
2024                         break;
2025                 }
2026                 mreq = mtod(m, struct ipv6_mreq *);
2027                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2028                         /*
2029                          * We use the unspecified address to specify to accept
2030                          * all multicast addresses. Only super user is allowed
2031                          * to do this.
2032                          */
2033                         if (suser(td))
2034                         {
2035                                 error = EACCES;
2036                                 break;
2037                         }
2038                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2039                         error = EINVAL;
2040                         break;
2041                 }
2042
2043                 /*
2044                  * If the interface is specified, validate it.
2045                  */
2046                 if (mreq->ipv6mr_interface < 0
2047                  || if_index < mreq->ipv6mr_interface) {
2048                         error = ENXIO;  /* XXX EINVAL? */
2049                         break;
2050                 }
2051                 /*
2052                  * If no interface was explicitly specified, choose an
2053                  * appropriate one according to the given multicast address.
2054                  */
2055                 if (mreq->ipv6mr_interface == 0) {
2056                         /*
2057                          * If the multicast address is in node-local scope,
2058                          * the interface should be a loopback interface.
2059                          * Otherwise, look up the routing table for the
2060                          * address, and choose the outgoing interface.
2061                          *   XXX: is it a good approach?
2062                          */
2063                         if (IN6_IS_ADDR_MC_NODELOCAL(&mreq->ipv6mr_multiaddr)) {
2064                                 ifp = &loif[0];
2065                         } else {
2066                                 ro.ro_rt = NULL;
2067                                 dst = (struct sockaddr_in6 *)&ro.ro_dst;
2068                                 bzero(dst, sizeof(*dst));
2069                                 dst->sin6_len = sizeof(struct sockaddr_in6);
2070                                 dst->sin6_family = AF_INET6;
2071                                 dst->sin6_addr = mreq->ipv6mr_multiaddr;
2072                                 rtalloc((struct route *)&ro);
2073                                 if (ro.ro_rt == NULL) {
2074                                         error = EADDRNOTAVAIL;
2075                                         break;
2076                                 }
2077                                 ifp = ro.ro_rt->rt_ifp;
2078                                 rtfree(ro.ro_rt);
2079                         }
2080                 } else
2081                         ifp = ifindex2ifnet[mreq->ipv6mr_interface];
2082
2083                 /*
2084                  * See if we found an interface, and confirm that it
2085                  * supports multicast
2086                  */
2087                 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
2088                         error = EADDRNOTAVAIL;
2089                         break;
2090                 }
2091                 /*
2092                  * Put interface index into the multicast address,
2093                  * if the address has link-local scope.
2094                  */
2095                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2096                         mreq->ipv6mr_multiaddr.s6_addr16[1]
2097                                 = htons(mreq->ipv6mr_interface);
2098                 }
2099                 /*
2100                  * See if the membership already exists.
2101                  */
2102                 for (imm = im6o->im6o_memberships.lh_first;
2103                      imm != NULL; imm = imm->i6mm_chain.le_next)
2104                         if (imm->i6mm_maddr->in6m_ifp == ifp &&
2105                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2106                                                &mreq->ipv6mr_multiaddr))
2107                                 break;
2108                 if (imm != NULL) {
2109                         error = EADDRINUSE;
2110                         break;
2111                 }
2112                 /*
2113                  * Everything looks good; add a new record to the multicast
2114                  * address list for the given interface.
2115                  */
2116                 imm = malloc(sizeof(*imm), M_IPMADDR, M_WAITOK);
2117                 if (imm == NULL) {
2118                         error = ENOBUFS;
2119                         break;
2120                 }
2121                 if ((imm->i6mm_maddr =
2122                      in6_addmulti(&mreq->ipv6mr_multiaddr, ifp, &error)) == NULL) {
2123                         free(imm, M_IPMADDR);
2124                         break;
2125                 }
2126                 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
2127                 break;
2128
2129         case IPV6_LEAVE_GROUP:
2130                 /*
2131                  * Drop a multicast group membership.
2132                  * Group must be a valid IP6 multicast address.
2133                  */
2134                 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
2135                         error = EINVAL;
2136                         break;
2137                 }
2138                 mreq = mtod(m, struct ipv6_mreq *);
2139                 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
2140                         if (suser(td)) {
2141                                 error = EACCES;
2142                                 break;
2143                         }
2144                 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
2145                         error = EINVAL;
2146                         break;
2147                 }
2148                 /*
2149                  * If an interface address was specified, get a pointer
2150                  * to its ifnet structure.
2151                  */
2152                 if (mreq->ipv6mr_interface < 0
2153                  || if_index < mreq->ipv6mr_interface) {
2154                         error = ENXIO;  /* XXX EINVAL? */
2155                         break;
2156                 }
2157                 ifp = ifindex2ifnet[mreq->ipv6mr_interface];
2158                 /*
2159                  * Put interface index into the multicast address,
2160                  * if the address has link-local scope.
2161                  */
2162                 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
2163                         mreq->ipv6mr_multiaddr.s6_addr16[1]
2164                                 = htons(mreq->ipv6mr_interface);
2165                 }
2166                 /*
2167                  * Find the membership in the membership list.
2168                  */
2169                 for (imm = im6o->im6o_memberships.lh_first;
2170                      imm != NULL; imm = imm->i6mm_chain.le_next) {
2171                         if ((ifp == NULL ||
2172                              imm->i6mm_maddr->in6m_ifp == ifp) &&
2173                             IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
2174                                                &mreq->ipv6mr_multiaddr))
2175                                 break;
2176                 }
2177                 if (imm == NULL) {
2178                         /* Unable to resolve interface */
2179                         error = EADDRNOTAVAIL;
2180                         break;
2181                 }
2182                 /*
2183                  * Give up the multicast address record to which the
2184                  * membership points.
2185                  */
2186                 LIST_REMOVE(imm, i6mm_chain);
2187                 in6_delmulti(imm->i6mm_maddr);
2188                 free(imm, M_IPMADDR);
2189                 break;
2190
2191         default:
2192                 error = EOPNOTSUPP;
2193                 break;
2194         }
2195
2196         /*
2197          * If all options have default values, no need to keep the mbuf.
2198          */
2199         if (im6o->im6o_multicast_ifp == NULL &&
2200             im6o->im6o_multicast_hlim == ip6_defmcasthlim &&
2201             im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP &&
2202             im6o->im6o_memberships.lh_first == NULL) {
2203                 free(*im6op, M_IPMOPTS);
2204                 *im6op = NULL;
2205         }
2206
2207         return(error);
2208 }
2209
2210 /*
2211  * Return the IP6 multicast options in response to user getsockopt().
2212  */
2213 static int
2214 ip6_getmoptions(optname, im6o, mp)
2215         int optname;
2216         struct ip6_moptions *im6o;
2217         struct mbuf **mp;
2218 {
2219         u_int *hlim, *loop, *ifindex;
2220
2221         *mp = m_get(M_WAIT, MT_HEADER);         /* XXX */
2222
2223         switch (optname) {
2224
2225         case IPV6_MULTICAST_IF:
2226                 ifindex = mtod(*mp, u_int *);
2227                 (*mp)->m_len = sizeof(u_int);
2228                 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL)
2229                         *ifindex = 0;
2230                 else
2231                         *ifindex = im6o->im6o_multicast_ifp->if_index;
2232                 return(0);
2233
2234         case IPV6_MULTICAST_HOPS:
2235                 hlim = mtod(*mp, u_int *);
2236                 (*mp)->m_len = sizeof(u_int);
2237                 if (im6o == NULL)
2238                         *hlim = ip6_defmcasthlim;
2239                 else
2240                         *hlim = im6o->im6o_multicast_hlim;
2241                 return(0);
2242
2243         case IPV6_MULTICAST_LOOP:
2244                 loop = mtod(*mp, u_int *);
2245                 (*mp)->m_len = sizeof(u_int);
2246                 if (im6o == NULL)
2247                         *loop = ip6_defmcasthlim;
2248                 else
2249                         *loop = im6o->im6o_multicast_loop;
2250                 return(0);
2251
2252         default:
2253                 return(EOPNOTSUPP);
2254         }
2255 }
2256
2257 /*
2258  * Discard the IP6 multicast options.
2259  */
2260 void
2261 ip6_freemoptions(im6o)
2262         struct ip6_moptions *im6o;
2263 {
2264         struct in6_multi_mship *imm;
2265
2266         if (im6o == NULL)
2267                 return;
2268
2269         while ((imm = im6o->im6o_memberships.lh_first) != NULL) {
2270                 LIST_REMOVE(imm, i6mm_chain);
2271                 if (imm->i6mm_maddr)
2272                         in6_delmulti(imm->i6mm_maddr);
2273                 free(imm, M_IPMADDR);
2274         }
2275         free(im6o, M_IPMOPTS);
2276 }
2277
2278 /*
2279  * Set IPv6 outgoing packet options based on advanced API.
2280  */
2281 int
2282 ip6_setpktoptions(control, opt, priv, needcopy)
2283         struct mbuf *control;
2284         struct ip6_pktopts *opt;
2285         int priv, needcopy;
2286 {
2287         struct cmsghdr *cm = 0;
2288
2289         if (control == 0 || opt == 0)
2290                 return(EINVAL);
2291
2292         init_ip6pktopts(opt);
2293
2294         /*
2295          * XXX: Currently, we assume all the optional information is stored
2296          * in a single mbuf.
2297          */
2298         if (control->m_next)
2299                 return(EINVAL);
2300
2301         for (; control->m_len; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2302                      control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2303                 cm = mtod(control, struct cmsghdr *);
2304                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2305                         return(EINVAL);
2306                 if (cm->cmsg_level != IPPROTO_IPV6)
2307                         continue;
2308
2309                 /*
2310                  * XXX should check if RFC2292 API is mixed with 2292bis API
2311                  */
2312                 switch (cm->cmsg_type) {
2313                 case IPV6_PKTINFO:
2314                         if (cm->cmsg_len != CMSG_LEN(sizeof(struct in6_pktinfo)))
2315                                 return(EINVAL);
2316                         if (needcopy) {
2317                                 /* XXX: Is it really WAITOK? */
2318                                 opt->ip6po_pktinfo =
2319                                         malloc(sizeof(struct in6_pktinfo),
2320                                                M_IP6OPT, M_WAITOK);
2321                                 bcopy(CMSG_DATA(cm), opt->ip6po_pktinfo,
2322                                     sizeof(struct in6_pktinfo));
2323                         } else
2324                                 opt->ip6po_pktinfo =
2325                                         (struct in6_pktinfo *)CMSG_DATA(cm);
2326                         if (opt->ip6po_pktinfo->ipi6_ifindex &&
2327                             IN6_IS_ADDR_LINKLOCAL(&opt->ip6po_pktinfo->ipi6_addr))
2328                                 opt->ip6po_pktinfo->ipi6_addr.s6_addr16[1] =
2329                                         htons(opt->ip6po_pktinfo->ipi6_ifindex);
2330
2331                         if (opt->ip6po_pktinfo->ipi6_ifindex > if_index
2332                          || opt->ip6po_pktinfo->ipi6_ifindex < 0) {
2333                                 return(ENXIO);
2334                         }
2335
2336                         /*
2337                          * Check if the requested source address is indeed a
2338                          * unicast address assigned to the node, and can be
2339                          * used as the packet's source address.
2340                          */
2341                         if (!IN6_IS_ADDR_UNSPECIFIED(&opt->ip6po_pktinfo->ipi6_addr)) {
2342                                 struct in6_ifaddr *ia6;
2343                                 struct sockaddr_in6 sin6;
2344
2345                                 bzero(&sin6, sizeof(sin6));
2346                                 sin6.sin6_len = sizeof(sin6);
2347                                 sin6.sin6_family = AF_INET6;
2348                                 sin6.sin6_addr =
2349                                         opt->ip6po_pktinfo->ipi6_addr;
2350                                 ia6 = (struct in6_ifaddr *)ifa_ifwithaddr(sin6tosa(&sin6));
2351                                 if (ia6 == NULL ||
2352                                     (ia6->ia6_flags & (IN6_IFF_ANYCAST |
2353                                                        IN6_IFF_NOTREADY)) != 0)
2354                                         return(EADDRNOTAVAIL);
2355                         }
2356                         break;
2357
2358                 case IPV6_HOPLIMIT:
2359                         if (cm->cmsg_len != CMSG_LEN(sizeof(int)))
2360                                 return(EINVAL);
2361
2362                         opt->ip6po_hlim = *(int *)CMSG_DATA(cm);
2363                         if (opt->ip6po_hlim < -1 || opt->ip6po_hlim > 255)
2364                                 return(EINVAL);
2365                         break;
2366
2367                 case IPV6_NEXTHOP:
2368                         if (!priv)
2369                                 return(EPERM);
2370
2371                         if (cm->cmsg_len < sizeof(u_char) ||
2372                             /* check if cmsg_len is large enough for sa_len */
2373                             cm->cmsg_len < CMSG_LEN(*CMSG_DATA(cm)))
2374                                 return(EINVAL);
2375
2376                         if (needcopy) {
2377                                 opt->ip6po_nexthop =
2378                                         malloc(*CMSG_DATA(cm),
2379                                                M_IP6OPT, M_WAITOK);
2380                                 bcopy(CMSG_DATA(cm),
2381                                       opt->ip6po_nexthop,
2382                                       *CMSG_DATA(cm));
2383                         } else
2384                                 opt->ip6po_nexthop =
2385                                         (struct sockaddr *)CMSG_DATA(cm);
2386                         break;
2387
2388                 case IPV6_HOPOPTS:
2389                 {
2390                         struct ip6_hbh *hbh;
2391                         int hbhlen;
2392
2393                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_hbh)))
2394                                 return(EINVAL);
2395                         hbh = (struct ip6_hbh *)CMSG_DATA(cm);
2396                         hbhlen = (hbh->ip6h_len + 1) << 3;
2397                         if (cm->cmsg_len != CMSG_LEN(hbhlen))
2398                                 return(EINVAL);
2399
2400                         if (needcopy) {
2401                                 opt->ip6po_hbh =
2402                                         malloc(hbhlen, M_IP6OPT, M_WAITOK);
2403                                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2404                         } else
2405                                 opt->ip6po_hbh = hbh;
2406                         break;
2407                 }
2408
2409                 case IPV6_DSTOPTS:
2410                 {
2411                         struct ip6_dest *dest, **newdest;
2412                         int destlen;
2413
2414                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_dest)))
2415                                 return(EINVAL);
2416                         dest = (struct ip6_dest *)CMSG_DATA(cm);
2417                         destlen = (dest->ip6d_len + 1) << 3;
2418                         if (cm->cmsg_len != CMSG_LEN(destlen))
2419                                 return(EINVAL);
2420
2421                         /*
2422                          * The old advacned API is ambiguous on this
2423                          * point. Our approach is to determine the
2424                          * position based according to the existence
2425                          * of a routing header. Note, however, that
2426                          * this depends on the order of the extension
2427                          * headers in the ancillary data; the 1st part
2428                          * of the destination options header must
2429                          * appear before the routing header in the
2430                          * ancillary data, too.
2431                          * RFC2292bis solved the ambiguity by
2432                          * introducing separate cmsg types.
2433                          */
2434                         if (opt->ip6po_rthdr == NULL)
2435                                 newdest = &opt->ip6po_dest1;
2436                         else
2437                                 newdest = &opt->ip6po_dest2;
2438
2439                         if (needcopy) {
2440                                 *newdest = malloc(destlen, M_IP6OPT, M_WAITOK);
2441                                 bcopy(dest, *newdest, destlen);
2442                         } else
2443                                 *newdest = dest;
2444
2445                         break;
2446                 }
2447
2448                 case IPV6_RTHDR:
2449                 {
2450                         struct ip6_rthdr *rth;
2451                         int rthlen;
2452
2453                         if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_rthdr)))
2454                                 return(EINVAL);
2455                         rth = (struct ip6_rthdr *)CMSG_DATA(cm);
2456                         rthlen = (rth->ip6r_len + 1) << 3;
2457                         if (cm->cmsg_len != CMSG_LEN(rthlen))
2458                                 return(EINVAL);
2459
2460                         switch (rth->ip6r_type) {
2461                         case IPV6_RTHDR_TYPE_0:
2462                                 /* must contain one addr */
2463                                 if (rth->ip6r_len == 0)
2464                                         return(EINVAL);
2465                                 /* length must be even */
2466                                 if (rth->ip6r_len % 2)
2467                                         return(EINVAL);
2468                                 if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2469                                         return(EINVAL);
2470                                 break;
2471                         default:
2472                                 return(EINVAL); /* not supported */
2473                         }
2474
2475                         if (needcopy) {
2476                                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT,
2477                                                           M_WAITOK);
2478                                 bcopy(rth, opt->ip6po_rthdr, rthlen);
2479                         } else
2480                                 opt->ip6po_rthdr = rth;
2481
2482                         break;
2483                 }
2484
2485                 default:
2486                         return(ENOPROTOOPT);
2487                 }
2488         }
2489
2490         return(0);
2491 }
2492
2493 /*
2494  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2495  * packet to the input queue of a specified interface.  Note that this
2496  * calls the output routine of the loopback "driver", but with an interface
2497  * pointer that might NOT be &loif -- easier than replicating that code here.
2498  */
2499 void
2500 ip6_mloopback(ifp, m, dst)
2501         struct ifnet *ifp;
2502         struct mbuf *m;
2503         struct sockaddr_in6 *dst;
2504 {
2505         struct mbuf *copym;
2506         struct ip6_hdr *ip6;
2507
2508         copym = m_copy(m, 0, M_COPYALL);
2509         if (copym == NULL)
2510                 return;
2511
2512         /*
2513          * Make sure to deep-copy IPv6 header portion in case the data
2514          * is in an mbuf cluster, so that we can safely override the IPv6
2515          * header portion later.
2516          */
2517         if ((copym->m_flags & M_EXT) != 0 ||
2518             copym->m_len < sizeof(struct ip6_hdr)) {
2519                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
2520                 if (copym == NULL)
2521                         return;
2522         }
2523
2524 #ifdef DIAGNOSTIC
2525         if (copym->m_len < sizeof(*ip6)) {
2526                 m_freem(copym);
2527                 return;
2528         }
2529 #endif
2530
2531         ip6 = mtod(copym, struct ip6_hdr *);
2532 #ifndef SCOPEDROUTING
2533         /*
2534          * clear embedded scope identifiers if necessary.
2535          * in6_clearscope will touch the addresses only when necessary.
2536          */
2537         in6_clearscope(&ip6->ip6_src);
2538         in6_clearscope(&ip6->ip6_dst);
2539 #endif
2540
2541         (void)if_simloop(ifp, copym, dst->sin6_family, NULL);
2542 }
2543
2544 /*
2545  * Chop IPv6 header off from the payload.
2546  */
2547 static int
2548 ip6_splithdr(m, exthdrs)
2549         struct mbuf *m;
2550         struct ip6_exthdrs *exthdrs;
2551 {
2552         struct mbuf *mh;
2553         struct ip6_hdr *ip6;
2554
2555         ip6 = mtod(m, struct ip6_hdr *);
2556         if (m->m_len > sizeof(*ip6)) {
2557                 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
2558                 if (mh == 0) {
2559                         m_freem(m);
2560                         return ENOBUFS;
2561                 }
2562                 M_MOVE_PKTHDR(mh, m);
2563                 MH_ALIGN(mh, sizeof(*ip6));
2564                 m->m_len -= sizeof(*ip6);
2565                 m->m_data += sizeof(*ip6);
2566                 mh->m_next = m;
2567                 m = mh;
2568                 m->m_len = sizeof(*ip6);
2569                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
2570         }
2571         exthdrs->ip6e_ip6 = m;
2572         return 0;
2573 }
2574
2575 /*
2576  * Compute IPv6 extension header length.
2577  */
2578 int
2579 ip6_optlen(in6p)
2580         struct in6pcb *in6p;
2581 {
2582         int len;
2583
2584         if (!in6p->in6p_outputopts)
2585                 return 0;
2586
2587         len = 0;
2588 #define elen(x) \
2589     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
2590
2591         len += elen(in6p->in6p_outputopts->ip6po_hbh);
2592         if (in6p->in6p_outputopts->ip6po_rthdr)
2593                 /* dest1 is valid with rthdr only */
2594                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
2595         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
2596         len += elen(in6p->in6p_outputopts->ip6po_dest2);
2597         return len;
2598 #undef elen
2599 }