sys/netinet6/ip6_output.c

   1 /*-
   2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $
  30  */
  31
  32 /*-
  33  * Copyright (c) 1982, 1986, 1988, 1990, 1993
  34  *      The Regents of the University of California.  All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  * 1. Redistributions of source code must retain the above copyright
  40  *    notice, this list of conditions and the following disclaimer.
  41  * 2. Redistributions in binary form must reproduce the above copyright
  42  *    notice, this list of conditions and the following disclaimer in the
  43  *    documentation and/or other materials provided with the distribution.
  44  * 4. Neither the name of the University nor the names of its contributors
  45  *    may be used to endorse or promote products derived from this software
  46  *    without specific prior written permission.
  47  *
  48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  58  * SUCH DAMAGE.
  59  *
  60  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  61  */
  62
  63 #include <sys/cdefs.h>
  64 __FBSDID("$FreeBSD$");
  65
  66 #include "opt_inet.h"
  67 #include "opt_inet6.h"
  68 #include "opt_ipfw.h"
  69 #include "opt_ipsec.h"
  70 #include "opt_sctp.h"
  71 #include "opt_route.h"
  72 #include "opt_rss.h"
  73
  74 #include <sys/param.h>
  75 #include <sys/kernel.h>
  76 #include <sys/malloc.h>
  77 #include <sys/mbuf.h>
  78 #include <sys/errno.h>
  79 #include <sys/priv.h>
  80 #include <sys/proc.h>
  81 #include <sys/protosw.h>
  82 #include <sys/socket.h>
  83 #include <sys/socketvar.h>
  84 #include <sys/syslog.h>
  85 #include <sys/ucred.h>
  86
  87 #include <machine/in_cksum.h>
  88
  89 #include <net/if.h>
  90 #include <net/if_var.h>
  91 #include <net/netisr.h>
  92 #include <net/route.h>
  93 #include <net/pfil.h>
  94 #include <net/rss_config.h>
  95 #include <net/vnet.h>
  96
  97 #include <netinet/in.h>
  98 #include <netinet/in_var.h>
  99 #include <netinet/ip_var.h>
 100 #include <netinet6/in6_var.h>
 101 #include <netinet/ip6.h>
 102 #include <netinet/icmp6.h>
 103 #include <netinet6/ip6_var.h>
 104 #include <netinet/in_pcb.h>
 105 #include <netinet/tcp_var.h>
 106 #include <netinet6/nd6.h>
 107 #include <netinet6/in6_rss.h>
 108
 109 #ifdef IPSEC
 110 #include <netipsec/ipsec.h>
 111 #include <netipsec/ipsec6.h>
 112 #include <netipsec/key.h>
 113 #include <netinet6/ip6_ipsec.h>
 114 #endif /* IPSEC */
 115 #ifdef SCTP
 116 #include <netinet/sctp.h>
 117 #include <netinet/sctp_crc32.h>
 118 #endif
 119
 120 #include <netinet6/ip6protosw.h>
 121 #include <netinet6/scope6_var.h>
 122
 123 #ifdef FLOWTABLE
 124 #include <net/flowtable.h>
 125 #endif
 126
 127 extern int in6_mcast_loop;
 128
 129 struct ip6_exthdrs {
 130         struct mbuf *ip6e_ip6;
 131         struct mbuf *ip6e_hbh;
 132         struct mbuf *ip6e_dest1;
 133         struct mbuf *ip6e_rthdr;
 134         struct mbuf *ip6e_dest2;
 135 };
 136
 137 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 138                            struct ucred *, int);
 139 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 140         struct socket *, struct sockopt *);
 141 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *);
 142 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 143         struct ucred *, int, int, int);
 144
 145 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 146 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 147         struct ip6_frag **);
 148 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 149 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 150 static int ip6_getpmtu(struct route_in6 *, struct route_in6 *,
 151         struct ifnet *, struct in6_addr *, u_long *, int *, u_int);
 152 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 153
 154
 155 /*
 156  * Make an extension header from option data.  hp is the source, and
 157  * mp is the destination.
 158  */
 159 #define MAKE_EXTHDR(hp, mp)                                             \
 160     do {                                                                \
 161         if (hp) {                                                       \
 162                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 163                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 164                     ((eh)->ip6e_len + 1) << 3);                         \
 165                 if (error)                                              \
 166                         goto freehdrs;                                  \
 167         }                                                               \
 168     } while (/*CONSTCOND*/ 0)
 169
 170 /*
 171  * Form a chain of extension headers.
 172  * m is the extension header mbuf
 173  * mp is the previous mbuf in the chain
 174  * p is the next header
 175  * i is the type of option.
 176  */
 177 #define MAKE_CHAIN(m, mp, p, i)\
 178     do {\
 179         if (m) {\
 180                 if (!hdrsplit) \
 181                         panic("assumption failed: hdr not split"); \
 182                 *mtod((m), u_char *) = *(p);\
 183                 *(p) = (i);\
 184                 p = mtod((m), u_char *);\
 185                 (m)->m_next = (mp)->m_next;\
 186                 (mp)->m_next = (m);\
 187                 (mp) = (m);\
 188         }\
 189     } while (/*CONSTCOND*/ 0)
 190
 191 void
 192 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 193 {
 194         u_short csum;
 195
 196         csum = in_cksum_skip(m, offset + plen, offset);
 197         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 198                 csum = 0xffff;
 199         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 200
 201         if (offset + sizeof(u_short) > m->m_len) {
 202                 printf("%s: delayed m_pullup, m->len: %d plen %u off %u "
 203                     "csum_flags=%b\n", __func__, m->m_len, plen, offset,
 204                     (int)m->m_pkthdr.csum_flags, CSUM_BITS);
 205                 /*
 206                  * XXX this should not happen, but if it does, the correct
 207                  * behavior may be to insert the checksum in the appropriate
 208                  * next mbuf in the chain.
 209                  */
 210                 return;
 211         }
 212         *(u_short *)(m->m_data + offset) = csum;
 213 }
 214
 215 int
 216 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 217     int mtu, uint32_t id)
 218 {
 219         struct mbuf *m, **mnext, *m_frgpart;
 220         struct ip6_hdr *ip6, *mhip6;
 221         struct ip6_frag *ip6f;
 222         int off;
 223         int error;
 224         int tlen = m0->m_pkthdr.len;
 225
 226         m = m0;
 227         ip6 = mtod(m, struct ip6_hdr *);
 228         mnext = &m->m_nextpkt;
 229
 230         for (off = hlen; off < tlen; off += mtu) {
 231                 m = m_gethdr(M_NOWAIT, MT_DATA);
 232                 if (!m) {
 233                         IP6STAT_INC(ip6s_odropped);
 234                         return (ENOBUFS);
 235                 }
 236                 m->m_flags = m0->m_flags & M_COPYFLAGS;
 237                 *mnext = m;
 238                 mnext = &m->m_nextpkt;
 239                 m->m_data += max_linkhdr;
 240                 mhip6 = mtod(m, struct ip6_hdr *);
 241                 *mhip6 = *ip6;
 242                 m->m_len = sizeof(*mhip6);
 243                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 244                 if (error) {
 245                         IP6STAT_INC(ip6s_odropped);
 246                         return (error);
 247                 }
 248                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 249                 if (off + mtu >= tlen)
 250                         mtu = tlen - off;
 251                 else
 252                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 253                 mhip6->ip6_plen = htons((u_short)(mtu + hlen +
 254                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 255                 if ((m_frgpart = m_copy(m0, off, mtu)) == 0) {
 256                         IP6STAT_INC(ip6s_odropped);
 257                         return (ENOBUFS);
 258                 }
 259                 m_cat(m, m_frgpart);
 260                 m->m_pkthdr.len = mtu + hlen + sizeof(*ip6f);
 261                 m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum;
 262                 m->m_pkthdr.rcvif = NULL;
 263                 ip6f->ip6f_reserved = 0;
 264                 ip6f->ip6f_ident = id;
 265                 ip6f->ip6f_nxt = nextproto;
 266                 IP6STAT_INC(ip6s_ofragments);
 267                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 268         }
 269
 270         return (0);
 271 }
 272
 273 /*
 274  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 275  * header (with pri, len, nxt, hlim, src, dst).
 276  * This function may modify ver and hlim only.
 277  * The mbuf chain containing the packet will be freed.
 278  * The mbuf opt, if present, will not be freed.
 279  * If route_in6 ro is present and has ro_rt initialized, route lookup would be
 280  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 281  * then result of route lookup is stored in ro->ro_rt.
 282  *
 283  * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
 284  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 285  * which is rt_mtu.
 286  *
 287  * ifpp - XXX: just for statistics
 288  */
 289 /*
 290  * XXX TODO: no flowid is assigned for outbound flows?
 291  */
 292 int
 293 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 294     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 295     struct ifnet **ifpp, struct inpcb *inp)
 296 {
 297         struct ip6_hdr *ip6;
 298         struct ifnet *ifp, *origifp;
 299         struct mbuf *m = m0;
 300         struct mbuf *mprev = NULL;
 301         int hlen, tlen, len;
 302         struct route_in6 ip6route;
 303         struct rtentry *rt = NULL;
 304         struct sockaddr_in6 *dst, src_sa, dst_sa;
 305         struct in6_addr odst;
 306         int error = 0;
 307         struct in6_ifaddr *ia = NULL;
 308         u_long mtu;
 309         int alwaysfrag, dontfrag;
 310         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 311         struct ip6_exthdrs exthdrs;
 312         struct in6_addr finaldst, src0, dst0;
 313         u_int32_t zone;
 314         struct route_in6 *ro_pmtu = NULL;
 315         int hdrsplit = 0;
 316         int sw_csum, tso;
 317         int needfiblookup;
 318         uint32_t fibnum;
 319         struct m_tag *fwd_tag = NULL;
 320         uint32_t id;
 321
 322         ip6 = mtod(m, struct ip6_hdr *);
 323         if (ip6 == NULL) {
 324                 printf ("ip6 is NULL");
 325                 goto bad;
 326         }
 327
 328         if (inp != NULL) {
 329                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 330                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 331                         /* unconditionally set flowid */
 332                         m->m_pkthdr.flowid = inp->inp_flowid;
 333                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 334                 }
 335         }
 336
 337         finaldst = ip6->ip6_dst;
 338         bzero(&exthdrs, sizeof(exthdrs));
 339         if (opt) {
 340                 /* Hop-by-Hop options header */
 341                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 342                 /* Destination options header(1st part) */
 343                 if (opt->ip6po_rthdr) {
 344                         /*
 345                          * Destination options header(1st part)
 346                          * This only makes sense with a routing header.
 347                          * See Section 9.2 of RFC 3542.
 348                          * Disabling this part just for MIP6 convenience is
 349                          * a bad idea.  We need to think carefully about a
 350                          * way to make the advanced API coexist with MIP6
 351                          * options, which might automatically be inserted in
 352                          * the kernel.
 353                          */
 354                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 355                 }
 356                 /* Routing header */
 357                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 358                 /* Destination options header(2nd part) */
 359                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 360         }
 361
 362 #ifdef IPSEC
 363         /*
 364          * IPSec checking which handles several cases.
 365          * FAST IPSEC: We re-injected the packet.
 366          * XXX: need scope argument.
 367          */
 368         switch(ip6_ipsec_output(&m, inp, &error))
 369         {
 370         case 1:                 /* Bad packet */
 371                 goto freehdrs;
 372         case -1:                /* IPSec done */
 373                 goto done;
 374         case 0:                 /* No IPSec */
 375         default:
 376                 break;
 377         }
 378 #endif /* IPSEC */
 379
 380         /*
 381          * Calculate the total length of the extension header chain.
 382          * Keep the length of the unfragmentable part for fragmentation.
 383          */
 384         optlen = 0;
 385         if (exthdrs.ip6e_hbh)
 386                 optlen += exthdrs.ip6e_hbh->m_len;
 387         if (exthdrs.ip6e_dest1)
 388                 optlen += exthdrs.ip6e_dest1->m_len;
 389         if (exthdrs.ip6e_rthdr)
 390                 optlen += exthdrs.ip6e_rthdr->m_len;
 391         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 392
 393         /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
 394         if (exthdrs.ip6e_dest2)
 395                 optlen += exthdrs.ip6e_dest2->m_len;
 396
 397         /*
 398          * If there is at least one extension header,
 399          * separate IP6 header from the payload.
 400          */
 401         if (optlen && !hdrsplit) {
 402                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 403                         m = NULL;
 404                         goto freehdrs;
 405                 }
 406                 m = exthdrs.ip6e_ip6;
 407                 hdrsplit++;
 408         }
 409
 410         /* adjust pointer */
 411         ip6 = mtod(m, struct ip6_hdr *);
 412
 413         /* adjust mbuf packet header length */
 414         m->m_pkthdr.len += optlen;
 415         plen = m->m_pkthdr.len - sizeof(*ip6);
 416
 417         /* If this is a jumbo payload, insert a jumbo payload option. */
 418         if (plen > IPV6_MAXPACKET) {
 419                 if (!hdrsplit) {
 420                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 421                                 m = NULL;
 422                                 goto freehdrs;
 423                         }
 424                         m = exthdrs.ip6e_ip6;
 425                         hdrsplit++;
 426                 }
 427                 /* adjust pointer */
 428                 ip6 = mtod(m, struct ip6_hdr *);
 429                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 430                         goto freehdrs;
 431                 ip6->ip6_plen = 0;
 432         } else
 433                 ip6->ip6_plen = htons(plen);
 434
 435         /*
 436          * Concatenate headers and fill in next header fields.
 437          * Here we have, on "m"
 438          *      IPv6 payload
 439          * and we insert headers accordingly.  Finally, we should be getting:
 440          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 441          *
 442          * during the header composing process, "m" points to IPv6 header.
 443          * "mprev" points to an extension header prior to esp.
 444          */
 445         u_char *nexthdrp = &ip6->ip6_nxt;
 446         mprev = m;
 447
 448         /*
 449          * we treat dest2 specially.  this makes IPsec processing
 450          * much easier.  the goal here is to make mprev point the
 451          * mbuf prior to dest2.
 452          *
 453          * result: IPv6 dest2 payload
 454          * m and mprev will point to IPv6 header.
 455          */
 456         if (exthdrs.ip6e_dest2) {
 457                 if (!hdrsplit)
 458                         panic("assumption failed: hdr not split");
 459                 exthdrs.ip6e_dest2->m_next = m->m_next;
 460                 m->m_next = exthdrs.ip6e_dest2;
 461                 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 462                 ip6->ip6_nxt = IPPROTO_DSTOPTS;
 463         }
 464
 465         /*
 466          * result: IPv6 hbh dest1 rthdr dest2 payload
 467          * m will point to IPv6 header.  mprev will point to the
 468          * extension header prior to dest2 (rthdr in the above case).
 469          */
 470         MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 471         MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 472                    IPPROTO_DSTOPTS);
 473         MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 474                    IPPROTO_ROUTING);
 475
 476         /*
 477          * If there is a routing header, discard the packet.
 478          */
 479         if (exthdrs.ip6e_rthdr) {
 480                  error = EINVAL;
 481                  goto bad;
 482         }
 483
 484         /* Source address validation */
 485         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 486             (flags & IPV6_UNSPECSRC) == 0) {
 487                 error = EOPNOTSUPP;
 488                 IP6STAT_INC(ip6s_badscope);
 489                 goto bad;
 490         }
 491         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 492                 error = EOPNOTSUPP;
 493                 IP6STAT_INC(ip6s_badscope);
 494                 goto bad;
 495         }
 496
 497         IP6STAT_INC(ip6s_localout);
 498
 499         /*
 500          * Route packet.
 501          */
 502         if (ro == 0) {
 503                 ro = &ip6route;
 504                 bzero((caddr_t)ro, sizeof(*ro));
 505         }
 506         ro_pmtu = ro;
 507         if (opt && opt->ip6po_rthdr)
 508                 ro = &opt->ip6po_route;
 509         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 510 #ifdef FLOWTABLE
 511         if (ro->ro_rt == NULL)
 512                 (void )flowtable_lookup(AF_INET6, m, (struct route *)ro);
 513 #endif
 514         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 515 again:
 516         /*
 517          * if specified, try to fill in the traffic class field.
 518          * do not override if a non-zero value is already set.
 519          * we check the diffserv field and the ecn field separately.
 520          */
 521         if (opt && opt->ip6po_tclass >= 0) {
 522                 int mask = 0;
 523
 524                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 525                         mask |= 0xfc;
 526                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 527                         mask |= 0x03;
 528                 if (mask != 0)
 529                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 530         }
 531
 532         /* fill in or override the hop limit field, if necessary. */
 533         if (opt && opt->ip6po_hlim != -1)
 534                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 535         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 536                 if (im6o != NULL)
 537                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 538                 else
 539                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 540         }
 541
 542         /* adjust pointer */
 543         ip6 = mtod(m, struct ip6_hdr *);
 544
 545         if (ro->ro_rt && fwd_tag == NULL) {
 546                 rt = ro->ro_rt;
 547                 ifp = ro->ro_rt->rt_ifp;
 548         } else {
 549                 if (fwd_tag == NULL) {
 550                         bzero(&dst_sa, sizeof(dst_sa));
 551                         dst_sa.sin6_family = AF_INET6;
 552                         dst_sa.sin6_len = sizeof(dst_sa);
 553                         dst_sa.sin6_addr = ip6->ip6_dst;
 554                 }
 555                 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
 556                     &rt, fibnum);
 557                 if (error != 0) {
 558                         if (ifp != NULL)
 559                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 560                         goto bad;
 561                 }
 562         }
 563         if (rt == NULL) {
 564                 /*
 565                  * If in6_selectroute() does not return a route entry,
 566                  * dst may not have been updated.
 567                  */
 568                 *dst = dst_sa;  /* XXX */
 569         }
 570
 571         /*
 572          * then rt (for unicast) and ifp must be non-NULL valid values.
 573          */
 574         if ((flags & IPV6_FORWARDING) == 0) {
 575                 /* XXX: the FORWARDING flag can be set for mrouting. */
 576                 in6_ifstat_inc(ifp, ifs6_out_request);
 577         }
 578         if (rt != NULL) {
 579                 ia = (struct in6_ifaddr *)(rt->rt_ifa);
 580                 counter_u64_add(rt->rt_pksent, 1);
 581         }
 582
 583
 584         /*
 585          * The outgoing interface must be in the zone of source and
 586          * destination addresses.
 587          */
 588         origifp = ifp;
 589
 590         src0 = ip6->ip6_src;
 591         if (in6_setscope(&src0, origifp, &zone))
 592                 goto badscope;
 593         bzero(&src_sa, sizeof(src_sa));
 594         src_sa.sin6_family = AF_INET6;
 595         src_sa.sin6_len = sizeof(src_sa);
 596         src_sa.sin6_addr = ip6->ip6_src;
 597         if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id)
 598                 goto badscope;
 599
 600         dst0 = ip6->ip6_dst;
 601         if (in6_setscope(&dst0, origifp, &zone))
 602                 goto badscope;
 603         /* re-initialize to be sure */
 604         bzero(&dst_sa, sizeof(dst_sa));
 605         dst_sa.sin6_family = AF_INET6;
 606         dst_sa.sin6_len = sizeof(dst_sa);
 607         dst_sa.sin6_addr = ip6->ip6_dst;
 608         if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) {
 609                 goto badscope;
 610         }
 611
 612         /* We should use ia_ifp to support the case of
 613          * sending packets to an address of our own.
 614          */
 615         if (ia != NULL && ia->ia_ifp)
 616                 ifp = ia->ia_ifp;
 617
 618         /* scope check is done. */
 619         goto routefound;
 620
 621   badscope:
 622         IP6STAT_INC(ip6s_badscope);
 623         in6_ifstat_inc(origifp, ifs6_out_discard);
 624         if (error == 0)
 625                 error = EHOSTUNREACH; /* XXX */
 626         goto bad;
 627
 628   routefound:
 629         if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 630                 if (opt && opt->ip6po_nextroute.ro_rt) {
 631                         /*
 632                          * The nexthop is explicitly specified by the
 633                          * application.  We assume the next hop is an IPv6
 634                          * address.
 635                          */
 636                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 637                 }
 638                 else if ((rt->rt_flags & RTF_GATEWAY))
 639                         dst = (struct sockaddr_in6 *)rt->rt_gateway;
 640         }
 641
 642         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 643                 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
 644         } else {
 645                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 646                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 647                 /*
 648                  * Confirm that the outgoing interface supports multicast.
 649                  */
 650                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 651                         IP6STAT_INC(ip6s_noroute);
 652                         in6_ifstat_inc(ifp, ifs6_out_discard);
 653                         error = ENETUNREACH;
 654                         goto bad;
 655                 }
 656                 if ((im6o == NULL && in6_mcast_loop) ||
 657                     (im6o && im6o->im6o_multicast_loop)) {
 658                         /*
 659                          * Loop back multicast datagram if not expressly
 660                          * forbidden to do so, even if we have not joined
 661                          * the address; protocols will filter it later,
 662                          * thus deferring a hash lookup and lock acquisition
 663                          * at the expense of an m_copym().
 664                          */
 665                         ip6_mloopback(ifp, m);
 666                 } else {
 667                         /*
 668                          * If we are acting as a multicast router, perform
 669                          * multicast forwarding as if the packet had just
 670                          * arrived on the interface to which we are about
 671                          * to send.  The multicast forwarding function
 672                          * recursively calls this function, using the
 673                          * IPV6_FORWARDING flag to prevent infinite recursion.
 674                          *
 675                          * Multicasts that are looped back by ip6_mloopback(),
 676                          * above, will be forwarded by the ip6_input() routine,
 677                          * if necessary.
 678                          */
 679                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 680                                 /*
 681                                  * XXX: ip6_mforward expects that rcvif is NULL
 682                                  * when it is called from the originating path.
 683                                  * However, it may not always be the case.
 684                                  */
 685                                 m->m_pkthdr.rcvif = NULL;
 686                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 687                                         m_freem(m);
 688                                         goto done;
 689                                 }
 690                         }
 691                 }
 692                 /*
 693                  * Multicasts with a hoplimit of zero may be looped back,
 694                  * above, but must not be transmitted on a network.
 695                  * Also, multicasts addressed to the loopback interface
 696                  * are not sent -- the above call to ip6_mloopback() will
 697                  * loop back a copy if this host actually belongs to the
 698                  * destination group on the loopback interface.
 699                  */
 700                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 701                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 702                         m_freem(m);
 703                         goto done;
 704                 }
 705         }
 706
 707         /*
 708          * Fill the outgoing inteface to tell the upper layer
 709          * to increment per-interface statistics.
 710          */
 711         if (ifpp)
 712                 *ifpp = ifp;
 713
 714         /* Determine path MTU. */
 715         if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu,
 716             &alwaysfrag, fibnum)) != 0)
 717                 goto bad;
 718
 719         /*
 720          * The caller of this function may specify to use the minimum MTU
 721          * in some cases.
 722          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 723          * setting.  The logic is a bit complicated; by default, unicast
 724          * packets will follow path MTU while multicast packets will be sent at
 725          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 726          * including unicast ones will be sent at the minimum MTU.  Multicast
 727          * packets will always be sent at the minimum MTU unless
 728          * IP6PO_MINMTU_DISABLE is explicitly specified.
 729          * See RFC 3542 for more details.
 730          */
 731         if (mtu > IPV6_MMTU) {
 732                 if ((flags & IPV6_MINMTU))
 733                         mtu = IPV6_MMTU;
 734                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 735                         mtu = IPV6_MMTU;
 736                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 737                          (opt == NULL ||
 738                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 739                         mtu = IPV6_MMTU;
 740                 }
 741         }
 742
 743         /*
 744          * clear embedded scope identifiers if necessary.
 745          * in6_clearscope will touch the addresses only when necessary.
 746          */
 747         in6_clearscope(&ip6->ip6_src);
 748         in6_clearscope(&ip6->ip6_dst);
 749
 750         /*
 751          * If the outgoing packet contains a hop-by-hop options header,
 752          * it must be examined and processed even by the source node.
 753          * (RFC 2460, section 4.)
 754          */
 755         if (exthdrs.ip6e_hbh) {
 756                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 757                 u_int32_t dummy; /* XXX unused */
 758                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 759
 760 #ifdef DIAGNOSTIC
 761                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 762                         panic("ip6e_hbh is not contiguous");
 763 #endif
 764                 /*
 765                  *  XXX: if we have to send an ICMPv6 error to the sender,
 766                  *       we need the M_LOOP flag since icmp6_error() expects
 767                  *       the IPv6 and the hop-by-hop options header are
 768                  *       contiguous unless the flag is set.
 769                  */
 770                 m->m_flags |= M_LOOP;
 771                 m->m_pkthdr.rcvif = ifp;
 772                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 773                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 774                     &dummy, &plen) < 0) {
 775                         /* m was already freed at this point */
 776                         error = EINVAL;/* better error? */
 777                         goto done;
 778                 }
 779                 m->m_flags &= ~M_LOOP; /* XXX */
 780                 m->m_pkthdr.rcvif = NULL;
 781         }
 782
 783         /* Jump over all PFIL processing if hooks are not active. */
 784         if (!PFIL_HOOKED(&V_inet6_pfil_hook))
 785                 goto passout;
 786
 787         odst = ip6->ip6_dst;
 788         /* Run through list of hooks for output packets. */
 789         error = pfil_run_hooks(&V_inet6_pfil_hook, &m, ifp, PFIL_OUT, inp);
 790         if (error != 0 || m == NULL)
 791                 goto done;
 792         ip6 = mtod(m, struct ip6_hdr *);
 793
 794         needfiblookup = 0;
 795         /* See if destination IP address was changed by packet filter. */
 796         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
 797                 m->m_flags |= M_SKIP_FIREWALL;
 798                 /* If destination is now ourself drop to ip6_input(). */
 799                 if (in6_localip(&ip6->ip6_dst)) {
 800                         m->m_flags |= M_FASTFWD_OURS;
 801                         if (m->m_pkthdr.rcvif == NULL)
 802                                 m->m_pkthdr.rcvif = V_loif;
 803                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 804                                 m->m_pkthdr.csum_flags |=
 805                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 806                                 m->m_pkthdr.csum_data = 0xffff;
 807                         }
 808 #ifdef SCTP
 809                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 810                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 811 #endif
 812                         error = netisr_queue(NETISR_IPV6, m);
 813                         goto done;
 814                 } else
 815                         needfiblookup = 1; /* Redo the routing table lookup. */
 816         }
 817         /* See if fib was changed by packet filter. */
 818         if (fibnum != M_GETFIB(m)) {
 819                 m->m_flags |= M_SKIP_FIREWALL;
 820                 fibnum = M_GETFIB(m);
 821                 RO_RTFREE(ro);
 822                 needfiblookup = 1;
 823         }
 824         if (needfiblookup)
 825                 goto again;
 826
 827         /* See if local, if yes, send it to netisr. */
 828         if (m->m_flags & M_FASTFWD_OURS) {
 829                 if (m->m_pkthdr.rcvif == NULL)
 830                         m->m_pkthdr.rcvif = V_loif;
 831                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 832                         m->m_pkthdr.csum_flags |=
 833                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 834                         m->m_pkthdr.csum_data = 0xffff;
 835                 }
 836 #ifdef SCTP
 837                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 838                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 839 #endif
 840                 error = netisr_queue(NETISR_IPV6, m);
 841                 goto done;
 842         }
 843         /* Or forward to some other address? */
 844         if ((m->m_flags & M_IP6_NEXTHOP) &&
 845             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 846                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 847                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
 848                 m->m_flags |= M_SKIP_FIREWALL;
 849                 m->m_flags &= ~M_IP6_NEXTHOP;
 850                 m_tag_delete(m, fwd_tag);
 851                 goto again;
 852         }
 853
 854 passout:
 855         /*
 856          * Send the packet to the outgoing interface.
 857          * If necessary, do IPv6 fragmentation before sending.
 858          *
 859          * the logic here is rather complex:
 860          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 861          * 1-a: send as is if tlen <= path mtu
 862          * 1-b: fragment if tlen > path mtu
 863          *
 864          * 2: if user asks us not to fragment (dontfrag == 1)
 865          * 2-a: send as is if tlen <= interface mtu
 866          * 2-b: error if tlen > interface mtu
 867          *
 868          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 869          *      always fragment
 870          *
 871          * 4: if dontfrag == 1 && alwaysfrag == 1
 872          *      error, as we cannot handle this conflicting request
 873          */
 874         sw_csum = m->m_pkthdr.csum_flags;
 875         if (!hdrsplit) {
 876                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
 877                 sw_csum &= ~ifp->if_hwassist;
 878         } else
 879                 tso = 0;
 880         /*
 881          * If we added extension headers, we will not do TSO and calculate the
 882          * checksums ourselves for now.
 883          * XXX-BZ  Need a framework to know when the NIC can handle it, even
 884          * with ext. hdrs.
 885          */
 886         if (sw_csum & CSUM_DELAY_DATA_IPV6) {
 887                 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
 888                 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
 889         }
 890 #ifdef SCTP
 891         if (sw_csum & CSUM_SCTP_IPV6) {
 892                 sw_csum &= ~CSUM_SCTP_IPV6;
 893                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
 894         }
 895 #endif
 896         m->m_pkthdr.csum_flags &= ifp->if_hwassist;
 897         tlen = m->m_pkthdr.len;
 898
 899         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
 900                 dontfrag = 1;
 901         else
 902                 dontfrag = 0;
 903         if (dontfrag && alwaysfrag) {   /* case 4 */
 904                 /* conflicting request - can't transmit */
 905                 error = EMSGSIZE;
 906                 goto bad;
 907         }
 908         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* case 2-b */
 909                 /*
 910                  * Even if the DONTFRAG option is specified, we cannot send the
 911                  * packet when the data length is larger than the MTU of the
 912                  * outgoing interface.
 913                  * Notify the error by sending IPV6_PATHMTU ancillary data if
 914                  * application wanted to know the MTU value. Also return an
 915                  * error code (this is not described in the API spec).
 916                  */
 917                 if (inp != NULL)
 918                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
 919                 error = EMSGSIZE;
 920                 goto bad;
 921         }
 922
 923         /*
 924          * transmit packet without fragmentation
 925          */
 926         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
 927                 struct in6_ifaddr *ia6;
 928
 929                 ip6 = mtod(m, struct ip6_hdr *);
 930                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
 931                 if (ia6) {
 932                         /* Record statistics for this interface address. */
 933                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
 934                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
 935                             m->m_pkthdr.len);
 936                         ifa_free(&ia6->ia_ifa);
 937                 }
 938                 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
 939                 goto done;
 940         }
 941
 942         /*
 943          * try to fragment the packet.  case 1-b and 3
 944          */
 945         if (mtu < IPV6_MMTU) {
 946                 /* path MTU cannot be less than IPV6_MMTU */
 947                 error = EMSGSIZE;
 948                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 949                 goto bad;
 950         } else if (ip6->ip6_plen == 0) {
 951                 /* jumbo payload cannot be fragmented */
 952                 error = EMSGSIZE;
 953                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 954                 goto bad;
 955         } else {
 956                 u_char nextproto;
 957
 958                 /*
 959                  * Too large for the destination or interface;
 960                  * fragment if possible.
 961                  * Must be able to put at least 8 bytes per fragment.
 962                  */
 963                 hlen = unfragpartlen;
 964                 if (mtu > IPV6_MAXPACKET)
 965                         mtu = IPV6_MAXPACKET;
 966
 967                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
 968                 if (len < 8) {
 969                         error = EMSGSIZE;
 970                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
 971                         goto bad;
 972                 }
 973
 974                 /*
 975                  * If the interface will not calculate checksums on
 976                  * fragmented packets, then do it here.
 977                  * XXX-BZ handle the hw offloading case.  Need flags.
 978                  */
 979                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 980                         in6_delayed_cksum(m, plen, hlen);
 981                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 982                 }
 983 #ifdef SCTP
 984                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
 985                         sctp_delayed_cksum(m, hlen);
 986                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 987                 }
 988 #endif
 989                 /*
 990                  * Change the next header field of the last header in the
 991                  * unfragmentable part.
 992                  */
 993                 if (exthdrs.ip6e_rthdr) {
 994                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
 995                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
 996                 } else if (exthdrs.ip6e_dest1) {
 997                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
 998                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
 999                 } else if (exthdrs.ip6e_hbh) {
1000                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1001                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1002                 } else {
1003                         nextproto = ip6->ip6_nxt;
1004                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1005                 }
1006
1007                 /*
1008                  * Loop through length of segment after first fragment,
1009                  * make new header and copy data of each part and link onto
1010                  * chain.
1011                  */
1012                 m0 = m;
1013                 id = htonl(ip6_randomid());
1014                 if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
1015                         goto sendorfree;
1016
1017                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1018         }
1019
1020         /*
1021          * Remove leading garbages.
1022          */
1023 sendorfree:
1024         m = m0->m_nextpkt;
1025         m0->m_nextpkt = 0;
1026         m_freem(m0);
1027         for (m0 = m; m; m = m0) {
1028                 m0 = m->m_nextpkt;
1029                 m->m_nextpkt = 0;
1030                 if (error == 0) {
1031                         /* Record statistics for this interface address. */
1032                         if (ia) {
1033                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1034                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1035                                     m->m_pkthdr.len);
1036                         }
1037                         error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
1038                 } else
1039                         m_freem(m);
1040         }
1041
1042         if (error == 0)
1043                 IP6STAT_INC(ip6s_fragmented);
1044
1045 done:
1046         if (ro == &ip6route)
1047                 RO_RTFREE(ro);
1048         if (ro_pmtu == &ip6route)
1049                 RO_RTFREE(ro_pmtu);
1050         return (error);
1051
1052 freehdrs:
1053         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1054         m_freem(exthdrs.ip6e_dest1);
1055         m_freem(exthdrs.ip6e_rthdr);
1056         m_freem(exthdrs.ip6e_dest2);
1057         /* FALLTHROUGH */
1058 bad:
1059         if (m)
1060                 m_freem(m);
1061         goto done;
1062 }
1063
1064 static int
1065 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1066 {
1067         struct mbuf *m;
1068
1069         if (hlen > MCLBYTES)
1070                 return (ENOBUFS); /* XXX */
1071
1072         if (hlen > MLEN)
1073                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1074         else
1075                 m = m_get(M_NOWAIT, MT_DATA);
1076         if (m == NULL)
1077                 return (ENOBUFS);
1078         m->m_len = hlen;
1079         if (hdr)
1080                 bcopy(hdr, mtod(m, caddr_t), hlen);
1081
1082         *mp = m;
1083         return (0);
1084 }
1085
1086 /*
1087  * Insert jumbo payload option.
1088  */
1089 static int
1090 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1091 {
1092         struct mbuf *mopt;
1093         u_char *optbuf;
1094         u_int32_t v;
1095
1096 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1097
1098         /*
1099          * If there is no hop-by-hop options header, allocate new one.
1100          * If there is one but it doesn't have enough space to store the
1101          * jumbo payload option, allocate a cluster to store the whole options.
1102          * Otherwise, use it to store the options.
1103          */
1104         if (exthdrs->ip6e_hbh == 0) {
1105                 mopt = m_get(M_NOWAIT, MT_DATA);
1106                 if (mopt == NULL)
1107                         return (ENOBUFS);
1108                 mopt->m_len = JUMBOOPTLEN;
1109                 optbuf = mtod(mopt, u_char *);
1110                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1111                 exthdrs->ip6e_hbh = mopt;
1112         } else {
1113                 struct ip6_hbh *hbh;
1114
1115                 mopt = exthdrs->ip6e_hbh;
1116                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1117                         /*
1118                          * XXX assumption:
1119                          * - exthdrs->ip6e_hbh is not referenced from places
1120                          *   other than exthdrs.
1121                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1122                          */
1123                         int oldoptlen = mopt->m_len;
1124                         struct mbuf *n;
1125
1126                         /*
1127                          * XXX: give up if the whole (new) hbh header does
1128                          * not fit even in an mbuf cluster.
1129                          */
1130                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1131                                 return (ENOBUFS);
1132
1133                         /*
1134                          * As a consequence, we must always prepare a cluster
1135                          * at this point.
1136                          */
1137                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1138                         if (n == NULL)
1139                                 return (ENOBUFS);
1140                         n->m_len = oldoptlen + JUMBOOPTLEN;
1141                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1142                             oldoptlen);
1143                         optbuf = mtod(n, caddr_t) + oldoptlen;
1144                         m_freem(mopt);
1145                         mopt = exthdrs->ip6e_hbh = n;
1146                 } else {
1147                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1148                         mopt->m_len += JUMBOOPTLEN;
1149                 }
1150                 optbuf[0] = IP6OPT_PADN;
1151                 optbuf[1] = 1;
1152
1153                 /*
1154                  * Adjust the header length according to the pad and
1155                  * the jumbo payload option.
1156                  */
1157                 hbh = mtod(mopt, struct ip6_hbh *);
1158                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1159         }
1160
1161         /* fill in the option. */
1162         optbuf[2] = IP6OPT_JUMBO;
1163         optbuf[3] = 4;
1164         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1165         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1166
1167         /* finally, adjust the packet header length */
1168         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1169
1170         return (0);
1171 #undef JUMBOOPTLEN
1172 }
1173
1174 /*
1175  * Insert fragment header and copy unfragmentable header portions.
1176  */
1177 static int
1178 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1179     struct ip6_frag **frghdrp)
1180 {
1181         struct mbuf *n, *mlast;
1182
1183         if (hlen > sizeof(struct ip6_hdr)) {
1184                 n = m_copym(m0, sizeof(struct ip6_hdr),
1185                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1186                 if (n == 0)
1187                         return (ENOBUFS);
1188                 m->m_next = n;
1189         } else
1190                 n = m;
1191
1192         /* Search for the last mbuf of unfragmentable part. */
1193         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1194                 ;
1195
1196         if (M_WRITABLE(mlast) &&
1197             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1198                 /* use the trailing space of the last mbuf for the fragment hdr */
1199                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1200                     mlast->m_len);
1201                 mlast->m_len += sizeof(struct ip6_frag);
1202                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1203         } else {
1204                 /* allocate a new mbuf for the fragment header */
1205                 struct mbuf *mfrg;
1206
1207                 mfrg = m_get(M_NOWAIT, MT_DATA);
1208                 if (mfrg == NULL)
1209                         return (ENOBUFS);
1210                 mfrg->m_len = sizeof(struct ip6_frag);
1211                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1212                 mlast->m_next = mfrg;
1213         }
1214
1215         return (0);
1216 }
1217
1218 static int
1219 ip6_getpmtu(struct route_in6 *ro_pmtu, struct route_in6 *ro,
1220     struct ifnet *ifp, struct in6_addr *dst, u_long *mtup,
1221     int *alwaysfragp, u_int fibnum)
1222 {
1223         u_int32_t mtu = 0;
1224         int alwaysfrag = 0;
1225         int error = 0;
1226
1227         if (ro_pmtu != ro) {
1228                 /* The first hop and the final destination may differ. */
1229                 struct sockaddr_in6 *sa6_dst =
1230                     (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1231                 if (ro_pmtu->ro_rt &&
1232                     ((ro_pmtu->ro_rt->rt_flags & RTF_UP) == 0 ||
1233                      !IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))) {
1234                         RTFREE(ro_pmtu->ro_rt);
1235                         ro_pmtu->ro_rt = (struct rtentry *)NULL;
1236                 }
1237                 if (ro_pmtu->ro_rt == NULL) {
1238                         bzero(sa6_dst, sizeof(*sa6_dst));
1239                         sa6_dst->sin6_family = AF_INET6;
1240                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1241                         sa6_dst->sin6_addr = *dst;
1242
1243                         in6_rtalloc(ro_pmtu, fibnum);
1244                 }
1245         }
1246         if (ro_pmtu->ro_rt) {
1247                 u_int32_t ifmtu;
1248                 struct in_conninfo inc;
1249
1250                 bzero(&inc, sizeof(inc));
1251                 inc.inc_flags |= INC_ISIPV6;
1252                 inc.inc6_faddr = *dst;
1253
1254                 if (ifp == NULL)
1255                         ifp = ro_pmtu->ro_rt->rt_ifp;
1256                 ifmtu = IN6_LINKMTU(ifp);
1257                 mtu = tcp_hc_getmtu(&inc);
1258                 if (mtu)
1259                         mtu = min(mtu, ro_pmtu->ro_rt->rt_mtu);
1260                 else
1261                         mtu = ro_pmtu->ro_rt->rt_mtu;
1262                 if (mtu == 0)
1263                         mtu = ifmtu;
1264                 else if (mtu < IPV6_MMTU) {
1265                         /*
1266                          * RFC2460 section 5, last paragraph:
1267                          * if we record ICMPv6 too big message with
1268                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1269                          * or smaller, with framgent header attached.
1270                          * (fragment header is needed regardless from the
1271                          * packet size, for translators to identify packets)
1272                          */
1273                         alwaysfrag = 1;
1274                         mtu = IPV6_MMTU;
1275                 }
1276         } else if (ifp) {
1277                 mtu = IN6_LINKMTU(ifp);
1278         } else
1279                 error = EHOSTUNREACH; /* XXX */
1280
1281         *mtup = mtu;
1282         if (alwaysfragp)
1283                 *alwaysfragp = alwaysfrag;
1284         return (error);
1285 }
1286
1287 /*
1288  * IP6 socket option processing.
1289  */
1290 int
1291 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1292 {
1293         int optdatalen, uproto;
1294         void *optdata;
1295         struct inpcb *in6p = sotoinpcb(so);
1296         int error, optval;
1297         int level, op, optname;
1298         int optlen;
1299         struct thread *td;
1300 #ifdef  RSS
1301         uint32_t rss_bucket;
1302         int retval;
1303 #endif
1304
1305         level = sopt->sopt_level;
1306         op = sopt->sopt_dir;
1307         optname = sopt->sopt_name;
1308         optlen = sopt->sopt_valsize;
1309         td = sopt->sopt_td;
1310         error = 0;
1311         optval = 0;
1312         uproto = (int)so->so_proto->pr_protocol;
1313
1314         if (level != IPPROTO_IPV6) {
1315                 error = EINVAL;
1316
1317                 if (sopt->sopt_level == SOL_SOCKET &&
1318                     sopt->sopt_dir == SOPT_SET) {
1319                         switch (sopt->sopt_name) {
1320                         case SO_REUSEADDR:
1321                                 INP_WLOCK(in6p);
1322                                 if ((so->so_options & SO_REUSEADDR) != 0)
1323                                         in6p->inp_flags2 |= INP_REUSEADDR;
1324                                 else
1325                                         in6p->inp_flags2 &= ~INP_REUSEADDR;
1326                                 INP_WUNLOCK(in6p);
1327                                 error = 0;
1328                                 break;
1329                         case SO_REUSEPORT:
1330                                 INP_WLOCK(in6p);
1331                                 if ((so->so_options & SO_REUSEPORT) != 0)
1332                                         in6p->inp_flags2 |= INP_REUSEPORT;
1333                                 else
1334                                         in6p->inp_flags2 &= ~INP_REUSEPORT;
1335                                 INP_WUNLOCK(in6p);
1336                                 error = 0;
1337                                 break;
1338                         case SO_SETFIB:
1339                                 INP_WLOCK(in6p);
1340                                 in6p->inp_inc.inc_fibnum = so->so_fibnum;
1341                                 INP_WUNLOCK(in6p);
1342                                 error = 0;
1343                                 break;
1344                         default:
1345                                 break;
1346                         }
1347                 }
1348         } else {                /* level == IPPROTO_IPV6 */
1349                 switch (op) {
1350
1351                 case SOPT_SET:
1352                         switch (optname) {
1353                         case IPV6_2292PKTOPTIONS:
1354 #ifdef IPV6_PKTOPTIONS
1355                         case IPV6_PKTOPTIONS:
1356 #endif
1357                         {
1358                                 struct mbuf *m;
1359
1360                                 error = soopt_getm(sopt, &m); /* XXX */
1361                                 if (error != 0)
1362                                         break;
1363                                 error = soopt_mcopyin(sopt, m); /* XXX */
1364                                 if (error != 0)
1365                                         break;
1366                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1367                                                     m, so, sopt);
1368                                 m_freem(m); /* XXX */
1369                                 break;
1370                         }
1371
1372                         /*
1373                          * Use of some Hop-by-Hop options or some
1374                          * Destination options, might require special
1375                          * privilege.  That is, normal applications
1376                          * (without special privilege) might be forbidden
1377                          * from setting certain options in outgoing packets,
1378                          * and might never see certain options in received
1379                          * packets. [RFC 2292 Section 6]
1380                          * KAME specific note:
1381                          *  KAME prevents non-privileged users from sending or
1382                          *  receiving ANY hbh/dst options in order to avoid
1383                          *  overhead of parsing options in the kernel.
1384                          */
1385                         case IPV6_RECVHOPOPTS:
1386                         case IPV6_RECVDSTOPTS:
1387                         case IPV6_RECVRTHDRDSTOPTS:
1388                                 if (td != NULL) {
1389                                         error = priv_check(td,
1390                                             PRIV_NETINET_SETHDROPTS);
1391                                         if (error)
1392                                                 break;
1393                                 }
1394                                 /* FALLTHROUGH */
1395                         case IPV6_UNICAST_HOPS:
1396                         case IPV6_HOPLIMIT:
1397
1398                         case IPV6_RECVPKTINFO:
1399                         case IPV6_RECVHOPLIMIT:
1400                         case IPV6_RECVRTHDR:
1401                         case IPV6_RECVPATHMTU:
1402                         case IPV6_RECVTCLASS:
1403                         case IPV6_V6ONLY:
1404                         case IPV6_AUTOFLOWLABEL:
1405                         case IPV6_BINDANY:
1406                         case IPV6_BINDMULTI:
1407 #ifdef  RSS
1408                         case IPV6_RSS_LISTEN_BUCKET:
1409 #endif
1410                                 if (optname == IPV6_BINDANY && td != NULL) {
1411                                         error = priv_check(td,
1412                                             PRIV_NETINET_BINDANY);
1413                                         if (error)
1414                                                 break;
1415                                 }
1416
1417                                 if (optlen != sizeof(int)) {
1418                                         error = EINVAL;
1419                                         break;
1420                                 }
1421                                 error = sooptcopyin(sopt, &optval,
1422                                         sizeof optval, sizeof optval);
1423                                 if (error)
1424                                         break;
1425                                 switch (optname) {
1426
1427                                 case IPV6_UNICAST_HOPS:
1428                                         if (optval < -1 || optval >= 256)
1429                                                 error = EINVAL;
1430                                         else {
1431                                                 /* -1 = kernel default */
1432                                                 in6p->in6p_hops = optval;
1433                                                 if ((in6p->inp_vflag &
1434                                                      INP_IPV4) != 0)
1435                                                         in6p->inp_ip_ttl = optval;
1436                                         }
1437                                         break;
1438 #define OPTSET(bit) \
1439 do { \
1440         INP_WLOCK(in6p); \
1441         if (optval) \
1442                 in6p->inp_flags |= (bit); \
1443         else \
1444                 in6p->inp_flags &= ~(bit); \
1445         INP_WUNLOCK(in6p); \
1446 } while (/*CONSTCOND*/ 0)
1447 #define OPTSET2292(bit) \
1448 do { \
1449         INP_WLOCK(in6p); \
1450         in6p->inp_flags |= IN6P_RFC2292; \
1451         if (optval) \
1452                 in6p->inp_flags |= (bit); \
1453         else \
1454                 in6p->inp_flags &= ~(bit); \
1455         INP_WUNLOCK(in6p); \
1456 } while (/*CONSTCOND*/ 0)
1457 #define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0)
1458
1459 #define OPTSET2(bit, val) do {                                          \
1460         INP_WLOCK(in6p);                                                \
1461         if (val)                                                        \
1462                 in6p->inp_flags2 |= bit;                                \
1463         else                                                            \
1464                 in6p->inp_flags2 &= ~bit;                               \
1465         INP_WUNLOCK(in6p);                                              \
1466 } while (0)
1467 #define OPTBIT2(bit) (in6p->inp_flags2 & (bit) ? 1 : 0)
1468
1469                                 case IPV6_RECVPKTINFO:
1470                                         /* cannot mix with RFC2292 */
1471                                         if (OPTBIT(IN6P_RFC2292)) {
1472                                                 error = EINVAL;
1473                                                 break;
1474                                         }
1475                                         OPTSET(IN6P_PKTINFO);
1476                                         break;
1477
1478                                 case IPV6_HOPLIMIT:
1479                                 {
1480                                         struct ip6_pktopts **optp;
1481
1482                                         /* cannot mix with RFC2292 */
1483                                         if (OPTBIT(IN6P_RFC2292)) {
1484                                                 error = EINVAL;
1485                                                 break;
1486                                         }
1487                                         optp = &in6p->in6p_outputopts;
1488                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1489                                             (u_char *)&optval, sizeof(optval),
1490                                             optp, (td != NULL) ? td->td_ucred :
1491                                             NULL, uproto);
1492                                         break;
1493                                 }
1494
1495                                 case IPV6_RECVHOPLIMIT:
1496                                         /* cannot mix with RFC2292 */
1497                                         if (OPTBIT(IN6P_RFC2292)) {
1498                                                 error = EINVAL;
1499                                                 break;
1500                                         }
1501                                         OPTSET(IN6P_HOPLIMIT);
1502                                         break;
1503
1504                                 case IPV6_RECVHOPOPTS:
1505                                         /* cannot mix with RFC2292 */
1506                                         if (OPTBIT(IN6P_RFC2292)) {
1507                                                 error = EINVAL;
1508                                                 break;
1509                                         }
1510                                         OPTSET(IN6P_HOPOPTS);
1511                                         break;
1512
1513                                 case IPV6_RECVDSTOPTS:
1514                                         /* cannot mix with RFC2292 */
1515                                         if (OPTBIT(IN6P_RFC2292)) {
1516                                                 error = EINVAL;
1517                                                 break;
1518                                         }
1519                                         OPTSET(IN6P_DSTOPTS);
1520                                         break;
1521
1522                                 case IPV6_RECVRTHDRDSTOPTS:
1523                                         /* cannot mix with RFC2292 */
1524                                         if (OPTBIT(IN6P_RFC2292)) {
1525                                                 error = EINVAL;
1526                                                 break;
1527                                         }
1528                                         OPTSET(IN6P_RTHDRDSTOPTS);
1529                                         break;
1530
1531                                 case IPV6_RECVRTHDR:
1532                                         /* cannot mix with RFC2292 */
1533                                         if (OPTBIT(IN6P_RFC2292)) {
1534                                                 error = EINVAL;
1535                                                 break;
1536                                         }
1537                                         OPTSET(IN6P_RTHDR);
1538                                         break;
1539
1540                                 case IPV6_RECVPATHMTU:
1541                                         /*
1542                                          * We ignore this option for TCP
1543                                          * sockets.
1544                                          * (RFC3542 leaves this case
1545                                          * unspecified.)
1546                                          */
1547                                         if (uproto != IPPROTO_TCP)
1548                                                 OPTSET(IN6P_MTU);
1549                                         break;
1550
1551                                 case IPV6_V6ONLY:
1552                                         /*
1553                                          * make setsockopt(IPV6_V6ONLY)
1554                                          * available only prior to bind(2).
1555                                          * see ipng mailing list, Jun 22 2001.
1556                                          */
1557                                         if (in6p->inp_lport ||
1558                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
1559                                                 error = EINVAL;
1560                                                 break;
1561                                         }
1562                                         OPTSET(IN6P_IPV6_V6ONLY);
1563                                         if (optval)
1564                                                 in6p->inp_vflag &= ~INP_IPV4;
1565                                         else
1566                                                 in6p->inp_vflag |= INP_IPV4;
1567                                         break;
1568                                 case IPV6_RECVTCLASS:
1569                                         /* cannot mix with RFC2292 XXX */
1570                                         if (OPTBIT(IN6P_RFC2292)) {
1571                                                 error = EINVAL;
1572                                                 break;
1573                                         }
1574                                         OPTSET(IN6P_TCLASS);
1575                                         break;
1576                                 case IPV6_AUTOFLOWLABEL:
1577                                         OPTSET(IN6P_AUTOFLOWLABEL);
1578                                         break;
1579
1580                                 case IPV6_BINDANY:
1581                                         OPTSET(INP_BINDANY);
1582                                         break;
1583
1584                                 case IPV6_BINDMULTI:
1585                                         OPTSET2(INP_BINDMULTI, optval);
1586                                         break;
1587 #ifdef  RSS
1588                                 case IPV6_RSS_LISTEN_BUCKET:
1589                                         if ((optval >= 0) &&
1590                                             (optval < rss_getnumbuckets())) {
1591                                                 in6p->inp_rss_listen_bucket = optval;
1592                                                 OPTSET2(INP_RSS_BUCKET_SET, 1);
1593                                         } else {
1594                                                 error = EINVAL;
1595                                         }
1596                                         break;
1597 #endif
1598                                 }
1599                                 break;
1600
1601                         case IPV6_TCLASS:
1602                         case IPV6_DONTFRAG:
1603                         case IPV6_USE_MIN_MTU:
1604                         case IPV6_PREFER_TEMPADDR:
1605                                 if (optlen != sizeof(optval)) {
1606                                         error = EINVAL;
1607                                         break;
1608                                 }
1609                                 error = sooptcopyin(sopt, &optval,
1610                                         sizeof optval, sizeof optval);
1611                                 if (error)
1612                                         break;
1613                                 {
1614                                         struct ip6_pktopts **optp;
1615                                         optp = &in6p->in6p_outputopts;
1616                                         error = ip6_pcbopt(optname,
1617                                             (u_char *)&optval, sizeof(optval),
1618                                             optp, (td != NULL) ? td->td_ucred :
1619                                             NULL, uproto);
1620                                         break;
1621                                 }
1622
1623                         case IPV6_2292PKTINFO:
1624                         case IPV6_2292HOPLIMIT:
1625                         case IPV6_2292HOPOPTS:
1626                         case IPV6_2292DSTOPTS:
1627                         case IPV6_2292RTHDR:
1628                                 /* RFC 2292 */
1629                                 if (optlen != sizeof(int)) {
1630                                         error = EINVAL;
1631                                         break;
1632                                 }
1633                                 error = sooptcopyin(sopt, &optval,
1634                                         sizeof optval, sizeof optval);
1635                                 if (error)
1636                                         break;
1637                                 switch (optname) {
1638                                 case IPV6_2292PKTINFO:
1639                                         OPTSET2292(IN6P_PKTINFO);
1640                                         break;
1641                                 case IPV6_2292HOPLIMIT:
1642                                         OPTSET2292(IN6P_HOPLIMIT);
1643                                         break;
1644                                 case IPV6_2292HOPOPTS:
1645                                         /*
1646                                          * Check super-user privilege.
1647                                          * See comments for IPV6_RECVHOPOPTS.
1648                                          */
1649                                         if (td != NULL) {
1650                                                 error = priv_check(td,
1651                                                     PRIV_NETINET_SETHDROPTS);
1652                                                 if (error)
1653                                                         return (error);
1654                                         }
1655                                         OPTSET2292(IN6P_HOPOPTS);
1656                                         break;
1657                                 case IPV6_2292DSTOPTS:
1658                                         if (td != NULL) {
1659                                                 error = priv_check(td,
1660                                                     PRIV_NETINET_SETHDROPTS);
1661                                                 if (error)
1662                                                         return (error);
1663                                         }
1664                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1665                                         break;
1666                                 case IPV6_2292RTHDR:
1667                                         OPTSET2292(IN6P_RTHDR);
1668                                         break;
1669                                 }
1670                                 break;
1671                         case IPV6_PKTINFO:
1672                         case IPV6_HOPOPTS:
1673                         case IPV6_RTHDR:
1674                         case IPV6_DSTOPTS:
1675                         case IPV6_RTHDRDSTOPTS:
1676                         case IPV6_NEXTHOP:
1677                         {
1678                                 /* new advanced API (RFC3542) */
1679                                 u_char *optbuf;
1680                                 u_char optbuf_storage[MCLBYTES];
1681                                 int optlen;
1682                                 struct ip6_pktopts **optp;
1683
1684                                 /* cannot mix with RFC2292 */
1685                                 if (OPTBIT(IN6P_RFC2292)) {
1686                                         error = EINVAL;
1687                                         break;
1688                                 }
1689
1690                                 /*
1691                                  * We only ensure valsize is not too large
1692                                  * here.  Further validation will be done
1693                                  * later.
1694                                  */
1695                                 error = sooptcopyin(sopt, optbuf_storage,
1696                                     sizeof(optbuf_storage), 0);
1697                                 if (error)
1698                                         break;
1699                                 optlen = sopt->sopt_valsize;
1700                                 optbuf = optbuf_storage;
1701                                 optp = &in6p->in6p_outputopts;
1702                                 error = ip6_pcbopt(optname, optbuf, optlen,
1703                                     optp, (td != NULL) ? td->td_ucred : NULL,
1704                                     uproto);
1705                                 break;
1706                         }
1707 #undef OPTSET
1708
1709                         case IPV6_MULTICAST_IF:
1710                         case IPV6_MULTICAST_HOPS:
1711                         case IPV6_MULTICAST_LOOP:
1712                         case IPV6_JOIN_GROUP:
1713                         case IPV6_LEAVE_GROUP:
1714                         case IPV6_MSFILTER:
1715                         case MCAST_BLOCK_SOURCE:
1716                         case MCAST_UNBLOCK_SOURCE:
1717                         case MCAST_JOIN_GROUP:
1718                         case MCAST_LEAVE_GROUP:
1719                         case MCAST_JOIN_SOURCE_GROUP:
1720                         case MCAST_LEAVE_SOURCE_GROUP:
1721                                 error = ip6_setmoptions(in6p, sopt);
1722                                 break;
1723
1724                         case IPV6_PORTRANGE:
1725                                 error = sooptcopyin(sopt, &optval,
1726                                     sizeof optval, sizeof optval);
1727                                 if (error)
1728                                         break;
1729
1730                                 INP_WLOCK(in6p);
1731                                 switch (optval) {
1732                                 case IPV6_PORTRANGE_DEFAULT:
1733                                         in6p->inp_flags &= ~(INP_LOWPORT);
1734                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1735                                         break;
1736
1737                                 case IPV6_PORTRANGE_HIGH:
1738                                         in6p->inp_flags &= ~(INP_LOWPORT);
1739                                         in6p->inp_flags |= INP_HIGHPORT;
1740                                         break;
1741
1742                                 case IPV6_PORTRANGE_LOW:
1743                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1744                                         in6p->inp_flags |= INP_LOWPORT;
1745                                         break;
1746
1747                                 default:
1748                                         error = EINVAL;
1749                                         break;
1750                                 }
1751                                 INP_WUNLOCK(in6p);
1752                                 break;
1753
1754 #ifdef IPSEC
1755                         case IPV6_IPSEC_POLICY:
1756                         {
1757                                 caddr_t req;
1758                                 struct mbuf *m;
1759
1760                                 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1761                                         break;
1762                                 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1763                                         break;
1764                                 req = mtod(m, caddr_t);
1765                                 error = ipsec_set_policy(in6p, optname, req,
1766                                     m->m_len, (sopt->sopt_td != NULL) ?
1767                                     sopt->sopt_td->td_ucred : NULL);
1768                                 m_freem(m);
1769                                 break;
1770                         }
1771 #endif /* IPSEC */
1772
1773                         default:
1774                                 error = ENOPROTOOPT;
1775                                 break;
1776                         }
1777                         break;
1778
1779                 case SOPT_GET:
1780                         switch (optname) {
1781
1782                         case IPV6_2292PKTOPTIONS:
1783 #ifdef IPV6_PKTOPTIONS
1784                         case IPV6_PKTOPTIONS:
1785 #endif
1786                                 /*
1787                                  * RFC3542 (effectively) deprecated the
1788                                  * semantics of the 2292-style pktoptions.
1789                                  * Since it was not reliable in nature (i.e.,
1790                                  * applications had to expect the lack of some
1791                                  * information after all), it would make sense
1792                                  * to simplify this part by always returning
1793                                  * empty data.
1794                                  */
1795                                 sopt->sopt_valsize = 0;
1796                                 break;
1797
1798                         case IPV6_RECVHOPOPTS:
1799                         case IPV6_RECVDSTOPTS:
1800                         case IPV6_RECVRTHDRDSTOPTS:
1801                         case IPV6_UNICAST_HOPS:
1802                         case IPV6_RECVPKTINFO:
1803                         case IPV6_RECVHOPLIMIT:
1804                         case IPV6_RECVRTHDR:
1805                         case IPV6_RECVPATHMTU:
1806
1807                         case IPV6_V6ONLY:
1808                         case IPV6_PORTRANGE:
1809                         case IPV6_RECVTCLASS:
1810                         case IPV6_AUTOFLOWLABEL:
1811                         case IPV6_BINDANY:
1812                         case IPV6_FLOWID:
1813                         case IPV6_FLOWTYPE:
1814 #ifdef  RSS
1815                         case IPV6_RSSBUCKETID:
1816 #endif
1817                                 switch (optname) {
1818
1819                                 case IPV6_RECVHOPOPTS:
1820                                         optval = OPTBIT(IN6P_HOPOPTS);
1821                                         break;
1822
1823                                 case IPV6_RECVDSTOPTS:
1824                                         optval = OPTBIT(IN6P_DSTOPTS);
1825                                         break;
1826
1827                                 case IPV6_RECVRTHDRDSTOPTS:
1828                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
1829                                         break;
1830
1831                                 case IPV6_UNICAST_HOPS:
1832                                         optval = in6p->in6p_hops;
1833                                         break;
1834
1835                                 case IPV6_RECVPKTINFO:
1836                                         optval = OPTBIT(IN6P_PKTINFO);
1837                                         break;
1838
1839                                 case IPV6_RECVHOPLIMIT:
1840                                         optval = OPTBIT(IN6P_HOPLIMIT);
1841                                         break;
1842
1843                                 case IPV6_RECVRTHDR:
1844                                         optval = OPTBIT(IN6P_RTHDR);
1845                                         break;
1846
1847                                 case IPV6_RECVPATHMTU:
1848                                         optval = OPTBIT(IN6P_MTU);
1849                                         break;
1850
1851                                 case IPV6_V6ONLY:
1852                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
1853                                         break;
1854
1855                                 case IPV6_PORTRANGE:
1856                                     {
1857                                         int flags;
1858                                         flags = in6p->inp_flags;
1859                                         if (flags & INP_HIGHPORT)
1860                                                 optval = IPV6_PORTRANGE_HIGH;
1861                                         else if (flags & INP_LOWPORT)
1862                                                 optval = IPV6_PORTRANGE_LOW;
1863                                         else
1864                                                 optval = 0;
1865                                         break;
1866                                     }
1867                                 case IPV6_RECVTCLASS:
1868                                         optval = OPTBIT(IN6P_TCLASS);
1869                                         break;
1870
1871                                 case IPV6_AUTOFLOWLABEL:
1872                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
1873                                         break;
1874
1875                                 case IPV6_BINDANY:
1876                                         optval = OPTBIT(INP_BINDANY);
1877                                         break;
1878
1879                                 case IPV6_FLOWID:
1880                                         optval = in6p->inp_flowid;
1881                                         break;
1882
1883                                 case IPV6_FLOWTYPE:
1884                                         optval = in6p->inp_flowtype;
1885                                         break;
1886 #ifdef  RSS
1887                                 case IPV6_RSSBUCKETID:
1888                                         retval =
1889                                             rss_hash2bucket(in6p->inp_flowid,
1890                                             in6p->inp_flowtype,
1891                                             &rss_bucket);
1892                                         if (retval == 0)
1893                                                 optval = rss_bucket;
1894                                         else
1895                                                 error = EINVAL;
1896                                         break;
1897 #endif
1898
1899                                 case IPV6_BINDMULTI:
1900                                         optval = OPTBIT2(INP_BINDMULTI);
1901                                         break;
1902
1903                                 }
1904                                 if (error)
1905                                         break;
1906                                 error = sooptcopyout(sopt, &optval,
1907                                         sizeof optval);
1908                                 break;
1909
1910                         case IPV6_PATHMTU:
1911                         {
1912                                 u_long pmtu = 0;
1913                                 struct ip6_mtuinfo mtuinfo;
1914                                 struct route_in6 sro;
1915
1916                                 bzero(&sro, sizeof(sro));
1917
1918                                 if (!(so->so_state & SS_ISCONNECTED))
1919                                         return (ENOTCONN);
1920                                 /*
1921                                  * XXX: we dot not consider the case of source
1922                                  * routing, or optional information to specify
1923                                  * the outgoing interface.
1924                                  */
1925                                 error = ip6_getpmtu(&sro, NULL, NULL,
1926                                     &in6p->in6p_faddr, &pmtu, NULL,
1927                                     so->so_fibnum);
1928                                 if (sro.ro_rt)
1929                                         RTFREE(sro.ro_rt);
1930                                 if (error)
1931                                         break;
1932                                 if (pmtu > IPV6_MAXPACKET)
1933                                         pmtu = IPV6_MAXPACKET;
1934
1935                                 bzero(&mtuinfo, sizeof(mtuinfo));
1936                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
1937                                 optdata = (void *)&mtuinfo;
1938                                 optdatalen = sizeof(mtuinfo);
1939                                 error = sooptcopyout(sopt, optdata,
1940                                     optdatalen);
1941                                 break;
1942                         }
1943
1944                         case IPV6_2292PKTINFO:
1945                         case IPV6_2292HOPLIMIT:
1946                         case IPV6_2292HOPOPTS:
1947                         case IPV6_2292RTHDR:
1948                         case IPV6_2292DSTOPTS:
1949                                 switch (optname) {
1950                                 case IPV6_2292PKTINFO:
1951                                         optval = OPTBIT(IN6P_PKTINFO);
1952                                         break;
1953                                 case IPV6_2292HOPLIMIT:
1954                                         optval = OPTBIT(IN6P_HOPLIMIT);
1955                                         break;
1956                                 case IPV6_2292HOPOPTS:
1957                                         optval = OPTBIT(IN6P_HOPOPTS);
1958                                         break;
1959                                 case IPV6_2292RTHDR:
1960                                         optval = OPTBIT(IN6P_RTHDR);
1961                                         break;
1962                                 case IPV6_2292DSTOPTS:
1963                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
1964                                         break;
1965                                 }
1966                                 error = sooptcopyout(sopt, &optval,
1967                                     sizeof optval);
1968                                 break;
1969                         case IPV6_PKTINFO:
1970                         case IPV6_HOPOPTS:
1971                         case IPV6_RTHDR:
1972                         case IPV6_DSTOPTS:
1973                         case IPV6_RTHDRDSTOPTS:
1974                         case IPV6_NEXTHOP:
1975                         case IPV6_TCLASS:
1976                         case IPV6_DONTFRAG:
1977                         case IPV6_USE_MIN_MTU:
1978                         case IPV6_PREFER_TEMPADDR:
1979                                 error = ip6_getpcbopt(in6p->in6p_outputopts,
1980                                     optname, sopt);
1981                                 break;
1982
1983                         case IPV6_MULTICAST_IF:
1984                         case IPV6_MULTICAST_HOPS:
1985                         case IPV6_MULTICAST_LOOP:
1986                         case IPV6_MSFILTER:
1987                                 error = ip6_getmoptions(in6p, sopt);
1988                                 break;
1989
1990 #ifdef IPSEC
1991                         case IPV6_IPSEC_POLICY:
1992                           {
1993                                 caddr_t req = NULL;
1994                                 size_t len = 0;
1995                                 struct mbuf *m = NULL;
1996                                 struct mbuf **mp = &m;
1997                                 size_t ovalsize = sopt->sopt_valsize;
1998                                 caddr_t oval = (caddr_t)sopt->sopt_val;
1999
2000                                 error = soopt_getm(sopt, &m); /* XXX */
2001                                 if (error != 0)
2002                                         break;
2003                                 error = soopt_mcopyin(sopt, m); /* XXX */
2004                                 if (error != 0)
2005                                         break;
2006                                 sopt->sopt_valsize = ovalsize;
2007                                 sopt->sopt_val = oval;
2008                                 if (m) {
2009                                         req = mtod(m, caddr_t);
2010                                         len = m->m_len;
2011                                 }
2012                                 error = ipsec_get_policy(in6p, req, len, mp);
2013                                 if (error == 0)
2014                                         error = soopt_mcopyout(sopt, m); /* XXX */
2015                                 if (error == 0 && m)
2016                                         m_freem(m);
2017                                 break;
2018                           }
2019 #endif /* IPSEC */
2020
2021                         default:
2022                                 error = ENOPROTOOPT;
2023                                 break;
2024                         }
2025                         break;
2026                 }
2027         }
2028         return (error);
2029 }
2030
2031 int
2032 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2033 {
2034         int error = 0, optval, optlen;
2035         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2036         struct inpcb *in6p = sotoinpcb(so);
2037         int level, op, optname;
2038
2039         level = sopt->sopt_level;
2040         op = sopt->sopt_dir;
2041         optname = sopt->sopt_name;
2042         optlen = sopt->sopt_valsize;
2043
2044         if (level != IPPROTO_IPV6) {
2045                 return (EINVAL);
2046         }
2047
2048         switch (optname) {
2049         case IPV6_CHECKSUM:
2050                 /*
2051                  * For ICMPv6 sockets, no modification allowed for checksum
2052                  * offset, permit "no change" values to help existing apps.
2053                  *
2054                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2055                  * for an ICMPv6 socket will fail."
2056                  * The current behavior does not meet RFC3542.
2057                  */
2058                 switch (op) {
2059                 case SOPT_SET:
2060                         if (optlen != sizeof(int)) {
2061                                 error = EINVAL;
2062                                 break;
2063                         }
2064                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2065                                             sizeof(optval));
2066                         if (error)
2067                                 break;
2068                         if ((optval % 2) != 0) {
2069                                 /* the API assumes even offset values */
2070                                 error = EINVAL;
2071                         } else if (so->so_proto->pr_protocol ==
2072                             IPPROTO_ICMPV6) {
2073                                 if (optval != icmp6off)
2074                                         error = EINVAL;
2075                         } else
2076                                 in6p->in6p_cksum = optval;
2077                         break;
2078
2079                 case SOPT_GET:
2080                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2081                                 optval = icmp6off;
2082                         else
2083                                 optval = in6p->in6p_cksum;
2084
2085                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2086                         break;
2087
2088                 default:
2089                         error = EINVAL;
2090                         break;
2091                 }
2092                 break;
2093
2094         default:
2095                 error = ENOPROTOOPT;
2096                 break;
2097         }
2098
2099         return (error);
2100 }
2101
2102 /*
2103  * Set up IP6 options in pcb for insertion in output packets or
2104  * specifying behavior of outgoing packets.
2105  */
2106 static int
2107 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2108     struct socket *so, struct sockopt *sopt)
2109 {
2110         struct ip6_pktopts *opt = *pktopt;
2111         int error = 0;
2112         struct thread *td = sopt->sopt_td;
2113
2114         /* turn off any old options. */
2115         if (opt) {
2116 #ifdef DIAGNOSTIC
2117                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2118                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2119                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2120                         printf("ip6_pcbopts: all specified options are cleared.\n");
2121 #endif
2122                 ip6_clearpktopts(opt, -1);
2123         } else
2124                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2125         *pktopt = NULL;
2126
2127         if (!m || m->m_len == 0) {
2128                 /*
2129                  * Only turning off any previous options, regardless of
2130                  * whether the opt is just created or given.
2131                  */
2132                 free(opt, M_IP6OPT);
2133                 return (0);
2134         }
2135
2136         /*  set options specified by user. */
2137         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2138             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2139                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2140                 free(opt, M_IP6OPT);
2141                 return (error);
2142         }
2143         *pktopt = opt;
2144         return (0);
2145 }
2146
2147 /*
2148  * initialize ip6_pktopts.  beware that there are non-zero default values in
2149  * the struct.
2150  */
2151 void
2152 ip6_initpktopts(struct ip6_pktopts *opt)
2153 {
2154
2155         bzero(opt, sizeof(*opt));
2156         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2157         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2158         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2159         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2160 }
2161
2162 static int
2163 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2164     struct ucred *cred, int uproto)
2165 {
2166         struct ip6_pktopts *opt;
2167
2168         if (*pktopt == NULL) {
2169                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2170                     M_WAITOK);
2171                 ip6_initpktopts(*pktopt);
2172         }
2173         opt = *pktopt;
2174
2175         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2176 }
2177
2178 static int
2179 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt)
2180 {
2181         void *optdata = NULL;
2182         int optdatalen = 0;
2183         struct ip6_ext *ip6e;
2184         int error = 0;
2185         struct in6_pktinfo null_pktinfo;
2186         int deftclass = 0, on;
2187         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2188         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2189
2190         switch (optname) {
2191         case IPV6_PKTINFO:
2192                 optdata = (void *)&null_pktinfo;
2193                 if (pktopt && pktopt->ip6po_pktinfo) {
2194                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2195                             sizeof(null_pktinfo));
2196                         in6_clearscope(&null_pktinfo.ipi6_addr);
2197                 } else {
2198                         /* XXX: we don't have to do this every time... */
2199                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2200                 }
2201                 optdatalen = sizeof(struct in6_pktinfo);
2202                 break;
2203         case IPV6_TCLASS:
2204                 if (pktopt && pktopt->ip6po_tclass >= 0)
2205                         optdata = (void *)&pktopt->ip6po_tclass;
2206                 else
2207                         optdata = (void *)&deftclass;
2208                 optdatalen = sizeof(int);
2209                 break;
2210         case IPV6_HOPOPTS:
2211                 if (pktopt && pktopt->ip6po_hbh) {
2212                         optdata = (void *)pktopt->ip6po_hbh;
2213                         ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
2214                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2215                 }
2216                 break;
2217         case IPV6_RTHDR:
2218                 if (pktopt && pktopt->ip6po_rthdr) {
2219                         optdata = (void *)pktopt->ip6po_rthdr;
2220                         ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
2221                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2222                 }
2223                 break;
2224         case IPV6_RTHDRDSTOPTS:
2225                 if (pktopt && pktopt->ip6po_dest1) {
2226                         optdata = (void *)pktopt->ip6po_dest1;
2227                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
2228                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2229                 }
2230                 break;
2231         case IPV6_DSTOPTS:
2232                 if (pktopt && pktopt->ip6po_dest2) {
2233                         optdata = (void *)pktopt->ip6po_dest2;
2234                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
2235                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2236                 }
2237                 break;
2238         case IPV6_NEXTHOP:
2239                 if (pktopt && pktopt->ip6po_nexthop) {
2240                         optdata = (void *)pktopt->ip6po_nexthop;
2241                         optdatalen = pktopt->ip6po_nexthop->sa_len;
2242                 }
2243                 break;
2244         case IPV6_USE_MIN_MTU:
2245                 if (pktopt)
2246                         optdata = (void *)&pktopt->ip6po_minmtu;
2247                 else
2248                         optdata = (void *)&defminmtu;
2249                 optdatalen = sizeof(int);
2250                 break;
2251         case IPV6_DONTFRAG:
2252                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2253                         on = 1;
2254                 else
2255                         on = 0;
2256                 optdata = (void *)&on;
2257                 optdatalen = sizeof(on);
2258                 break;
2259         case IPV6_PREFER_TEMPADDR:
2260                 if (pktopt)
2261                         optdata = (void *)&pktopt->ip6po_prefer_tempaddr;
2262                 else
2263                         optdata = (void *)&defpreftemp;
2264                 optdatalen = sizeof(int);
2265                 break;
2266         default:                /* should not happen */
2267 #ifdef DIAGNOSTIC
2268                 panic("ip6_getpcbopt: unexpected option\n");
2269 #endif
2270                 return (ENOPROTOOPT);
2271         }
2272
2273         error = sooptcopyout(sopt, optdata, optdatalen);
2274
2275         return (error);
2276 }
2277
2278 void
2279 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2280 {
2281         if (pktopt == NULL)
2282                 return;
2283
2284         if (optname == -1 || optname == IPV6_PKTINFO) {
2285                 if (pktopt->ip6po_pktinfo)
2286                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2287                 pktopt->ip6po_pktinfo = NULL;
2288         }
2289         if (optname == -1 || optname == IPV6_HOPLIMIT)
2290                 pktopt->ip6po_hlim = -1;
2291         if (optname == -1 || optname == IPV6_TCLASS)
2292                 pktopt->ip6po_tclass = -1;
2293         if (optname == -1 || optname == IPV6_NEXTHOP) {
2294                 if (pktopt->ip6po_nextroute.ro_rt) {
2295                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2296                         pktopt->ip6po_nextroute.ro_rt = NULL;
2297                 }
2298                 if (pktopt->ip6po_nexthop)
2299                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2300                 pktopt->ip6po_nexthop = NULL;
2301         }
2302         if (optname == -1 || optname == IPV6_HOPOPTS) {
2303                 if (pktopt->ip6po_hbh)
2304                         free(pktopt->ip6po_hbh, M_IP6OPT);
2305                 pktopt->ip6po_hbh = NULL;
2306         }
2307         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2308                 if (pktopt->ip6po_dest1)
2309                         free(pktopt->ip6po_dest1, M_IP6OPT);
2310                 pktopt->ip6po_dest1 = NULL;
2311         }
2312         if (optname == -1 || optname == IPV6_RTHDR) {
2313                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2314                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2315                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2316                 if (pktopt->ip6po_route.ro_rt) {
2317                         RTFREE(pktopt->ip6po_route.ro_rt);
2318                         pktopt->ip6po_route.ro_rt = NULL;
2319                 }
2320         }
2321         if (optname == -1 || optname == IPV6_DSTOPTS) {
2322                 if (pktopt->ip6po_dest2)
2323                         free(pktopt->ip6po_dest2, M_IP6OPT);
2324                 pktopt->ip6po_dest2 = NULL;
2325         }
2326 }
2327
2328 #define PKTOPT_EXTHDRCPY(type) \
2329 do {\
2330         if (src->type) {\
2331                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2332                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2333                 if (dst->type == NULL && canwait == M_NOWAIT)\
2334                         goto bad;\
2335                 bcopy(src->type, dst->type, hlen);\
2336         }\
2337 } while (/*CONSTCOND*/ 0)
2338
2339 static int
2340 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2341 {
2342         if (dst == NULL || src == NULL)  {
2343                 printf("ip6_clearpktopts: invalid argument\n");
2344                 return (EINVAL);
2345         }
2346
2347         dst->ip6po_hlim = src->ip6po_hlim;
2348         dst->ip6po_tclass = src->ip6po_tclass;
2349         dst->ip6po_flags = src->ip6po_flags;
2350         dst->ip6po_minmtu = src->ip6po_minmtu;
2351         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2352         if (src->ip6po_pktinfo) {
2353                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2354                     M_IP6OPT, canwait);
2355                 if (dst->ip6po_pktinfo == NULL)
2356                         goto bad;
2357                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2358         }
2359         if (src->ip6po_nexthop) {
2360                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2361                     M_IP6OPT, canwait);
2362                 if (dst->ip6po_nexthop == NULL)
2363                         goto bad;
2364                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2365                     src->ip6po_nexthop->sa_len);
2366         }
2367         PKTOPT_EXTHDRCPY(ip6po_hbh);
2368         PKTOPT_EXTHDRCPY(ip6po_dest1);
2369         PKTOPT_EXTHDRCPY(ip6po_dest2);
2370         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2371         return (0);
2372
2373   bad:
2374         ip6_clearpktopts(dst, -1);
2375         return (ENOBUFS);
2376 }
2377 #undef PKTOPT_EXTHDRCPY
2378
2379 struct ip6_pktopts *
2380 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2381 {
2382         int error;
2383         struct ip6_pktopts *dst;
2384
2385         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2386         if (dst == NULL)
2387                 return (NULL);
2388         ip6_initpktopts(dst);
2389
2390         if ((error = copypktopts(dst, src, canwait)) != 0) {
2391                 free(dst, M_IP6OPT);
2392                 return (NULL);
2393         }
2394
2395         return (dst);
2396 }
2397
2398 void
2399 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2400 {
2401         if (pktopt == NULL)
2402                 return;
2403
2404         ip6_clearpktopts(pktopt, -1);
2405
2406         free(pktopt, M_IP6OPT);
2407 }
2408
2409 /*
2410  * Set IPv6 outgoing packet options based on advanced API.
2411  */
2412 int
2413 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2414     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2415 {
2416         struct cmsghdr *cm = 0;
2417
2418         if (control == NULL || opt == NULL)
2419                 return (EINVAL);
2420
2421         ip6_initpktopts(opt);
2422         if (stickyopt) {
2423                 int error;
2424
2425                 /*
2426                  * If stickyopt is provided, make a local copy of the options
2427                  * for this particular packet, then override them by ancillary
2428                  * objects.
2429                  * XXX: copypktopts() does not copy the cached route to a next
2430                  * hop (if any).  This is not very good in terms of efficiency,
2431                  * but we can allow this since this option should be rarely
2432                  * used.
2433                  */
2434                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2435                         return (error);
2436         }
2437
2438         /*
2439          * XXX: Currently, we assume all the optional information is stored
2440          * in a single mbuf.
2441          */
2442         if (control->m_next)
2443                 return (EINVAL);
2444
2445         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2446             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2447                 int error;
2448
2449                 if (control->m_len < CMSG_LEN(0))
2450                         return (EINVAL);
2451
2452                 cm = mtod(control, struct cmsghdr *);
2453                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2454                         return (EINVAL);
2455                 if (cm->cmsg_level != IPPROTO_IPV6)
2456                         continue;
2457
2458                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2459                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2460                 if (error)
2461                         return (error);
2462         }
2463
2464         return (0);
2465 }
2466
2467 /*
2468  * Set a particular packet option, as a sticky option or an ancillary data
2469  * item.  "len" can be 0 only when it's a sticky option.
2470  * We have 4 cases of combination of "sticky" and "cmsg":
2471  * "sticky=0, cmsg=0": impossible
2472  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2473  * "sticky=1, cmsg=0": RFC3542 socket option
2474  * "sticky=1, cmsg=1": RFC2292 socket option
2475  */
2476 static int
2477 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2478     struct ucred *cred, int sticky, int cmsg, int uproto)
2479 {
2480         int minmtupolicy, preftemp;
2481         int error;
2482
2483         if (!sticky && !cmsg) {
2484 #ifdef DIAGNOSTIC
2485                 printf("ip6_setpktopt: impossible case\n");
2486 #endif
2487                 return (EINVAL);
2488         }
2489
2490         /*
2491          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2492          * not be specified in the context of RFC3542.  Conversely,
2493          * RFC3542 types should not be specified in the context of RFC2292.
2494          */
2495         if (!cmsg) {
2496                 switch (optname) {
2497                 case IPV6_2292PKTINFO:
2498                 case IPV6_2292HOPLIMIT:
2499                 case IPV6_2292NEXTHOP:
2500                 case IPV6_2292HOPOPTS:
2501                 case IPV6_2292DSTOPTS:
2502                 case IPV6_2292RTHDR:
2503                 case IPV6_2292PKTOPTIONS:
2504                         return (ENOPROTOOPT);
2505                 }
2506         }
2507         if (sticky && cmsg) {
2508                 switch (optname) {
2509                 case IPV6_PKTINFO:
2510                 case IPV6_HOPLIMIT:
2511                 case IPV6_NEXTHOP:
2512                 case IPV6_HOPOPTS:
2513                 case IPV6_DSTOPTS:
2514                 case IPV6_RTHDRDSTOPTS:
2515                 case IPV6_RTHDR:
2516                 case IPV6_USE_MIN_MTU:
2517                 case IPV6_DONTFRAG:
2518                 case IPV6_TCLASS:
2519                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2520                         return (ENOPROTOOPT);
2521                 }
2522         }
2523
2524         switch (optname) {
2525         case IPV6_2292PKTINFO:
2526         case IPV6_PKTINFO:
2527         {
2528                 struct ifnet *ifp = NULL;
2529                 struct in6_pktinfo *pktinfo;
2530
2531                 if (len != sizeof(struct in6_pktinfo))
2532                         return (EINVAL);
2533
2534                 pktinfo = (struct in6_pktinfo *)buf;
2535
2536                 /*
2537                  * An application can clear any sticky IPV6_PKTINFO option by
2538                  * doing a "regular" setsockopt with ipi6_addr being
2539                  * in6addr_any and ipi6_ifindex being zero.
2540                  * [RFC 3542, Section 6]
2541                  */
2542                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2543                     pktinfo->ipi6_ifindex == 0 &&
2544                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2545                         ip6_clearpktopts(opt, optname);
2546                         break;
2547                 }
2548
2549                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2550                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2551                         return (EINVAL);
2552                 }
2553                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2554                         return (EINVAL);
2555                 /* validate the interface index if specified. */
2556                 if (pktinfo->ipi6_ifindex > V_if_index)
2557                          return (ENXIO);
2558                 if (pktinfo->ipi6_ifindex) {
2559                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2560                         if (ifp == NULL)
2561                                 return (ENXIO);
2562                 }
2563                 if (ifp != NULL && (
2564                     ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED))
2565                         return (ENETDOWN);
2566
2567                 if (ifp != NULL &&
2568                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2569                         struct in6_ifaddr *ia;
2570
2571                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2572                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2573                         if (ia == NULL)
2574                                 return (EADDRNOTAVAIL);
2575                         ifa_free(&ia->ia_ifa);
2576                 }
2577                 /*
2578                  * We store the address anyway, and let in6_selectsrc()
2579                  * validate the specified address.  This is because ipi6_addr
2580                  * may not have enough information about its scope zone, and
2581                  * we may need additional information (such as outgoing
2582                  * interface or the scope zone of a destination address) to
2583                  * disambiguate the scope.
2584                  * XXX: the delay of the validation may confuse the
2585                  * application when it is used as a sticky option.
2586                  */
2587                 if (opt->ip6po_pktinfo == NULL) {
2588                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2589                             M_IP6OPT, M_NOWAIT);
2590                         if (opt->ip6po_pktinfo == NULL)
2591                                 return (ENOBUFS);
2592                 }
2593                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2594                 break;
2595         }
2596
2597         case IPV6_2292HOPLIMIT:
2598         case IPV6_HOPLIMIT:
2599         {
2600                 int *hlimp;
2601
2602                 /*
2603                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2604                  * to simplify the ordering among hoplimit options.
2605                  */
2606                 if (optname == IPV6_HOPLIMIT && sticky)
2607                         return (ENOPROTOOPT);
2608
2609                 if (len != sizeof(int))
2610                         return (EINVAL);
2611                 hlimp = (int *)buf;
2612                 if (*hlimp < -1 || *hlimp > 255)
2613                         return (EINVAL);
2614
2615                 opt->ip6po_hlim = *hlimp;
2616                 break;
2617         }
2618
2619         case IPV6_TCLASS:
2620         {
2621                 int tclass;
2622
2623                 if (len != sizeof(int))
2624                         return (EINVAL);
2625                 tclass = *(int *)buf;
2626                 if (tclass < -1 || tclass > 255)
2627                         return (EINVAL);
2628
2629                 opt->ip6po_tclass = tclass;
2630                 break;
2631         }
2632
2633         case IPV6_2292NEXTHOP:
2634         case IPV6_NEXTHOP:
2635                 if (cred != NULL) {
2636                         error = priv_check_cred(cred,
2637                             PRIV_NETINET_SETHDROPTS, 0);
2638                         if (error)
2639                                 return (error);
2640                 }
2641
2642                 if (len == 0) { /* just remove the option */
2643                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
2644                         break;
2645                 }
2646
2647                 /* check if cmsg_len is large enough for sa_len */
2648                 if (len < sizeof(struct sockaddr) || len < *buf)
2649                         return (EINVAL);
2650
2651                 switch (((struct sockaddr *)buf)->sa_family) {
2652                 case AF_INET6:
2653                 {
2654                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2655                         int error;
2656
2657                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2658                                 return (EINVAL);
2659
2660                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2661                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2662                                 return (EINVAL);
2663                         }
2664                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2665                             != 0) {
2666                                 return (error);
2667                         }
2668                         break;
2669                 }
2670                 case AF_LINK:   /* should eventually be supported */
2671                 default:
2672                         return (EAFNOSUPPORT);
2673                 }
2674
2675                 /* turn off the previous option, then set the new option. */
2676                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2677                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2678                 if (opt->ip6po_nexthop == NULL)
2679                         return (ENOBUFS);
2680                 bcopy(buf, opt->ip6po_nexthop, *buf);
2681                 break;
2682
2683         case IPV6_2292HOPOPTS:
2684         case IPV6_HOPOPTS:
2685         {
2686                 struct ip6_hbh *hbh;
2687                 int hbhlen;
2688
2689                 /*
2690                  * XXX: We don't allow a non-privileged user to set ANY HbH
2691                  * options, since per-option restriction has too much
2692                  * overhead.
2693                  */
2694                 if (cred != NULL) {
2695                         error = priv_check_cred(cred,
2696                             PRIV_NETINET_SETHDROPTS, 0);
2697                         if (error)
2698                                 return (error);
2699                 }
2700
2701                 if (len == 0) {
2702                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
2703                         break;  /* just remove the option */
2704                 }
2705
2706                 /* message length validation */
2707                 if (len < sizeof(struct ip6_hbh))
2708                         return (EINVAL);
2709                 hbh = (struct ip6_hbh *)buf;
2710                 hbhlen = (hbh->ip6h_len + 1) << 3;
2711                 if (len != hbhlen)
2712                         return (EINVAL);
2713
2714                 /* turn off the previous option, then set the new option. */
2715                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2716                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2717                 if (opt->ip6po_hbh == NULL)
2718                         return (ENOBUFS);
2719                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2720
2721                 break;
2722         }
2723
2724         case IPV6_2292DSTOPTS:
2725         case IPV6_DSTOPTS:
2726         case IPV6_RTHDRDSTOPTS:
2727         {
2728                 struct ip6_dest *dest, **newdest = NULL;
2729                 int destlen;
2730
2731                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
2732                         error = priv_check_cred(cred,
2733                             PRIV_NETINET_SETHDROPTS, 0);
2734                         if (error)
2735                                 return (error);
2736                 }
2737
2738                 if (len == 0) {
2739                         ip6_clearpktopts(opt, optname);
2740                         break;  /* just remove the option */
2741                 }
2742
2743                 /* message length validation */
2744                 if (len < sizeof(struct ip6_dest))
2745                         return (EINVAL);
2746                 dest = (struct ip6_dest *)buf;
2747                 destlen = (dest->ip6d_len + 1) << 3;
2748                 if (len != destlen)
2749                         return (EINVAL);
2750
2751                 /*
2752                  * Determine the position that the destination options header
2753                  * should be inserted; before or after the routing header.
2754                  */
2755                 switch (optname) {
2756                 case IPV6_2292DSTOPTS:
2757                         /*
2758                          * The old advacned API is ambiguous on this point.
2759                          * Our approach is to determine the position based
2760                          * according to the existence of a routing header.
2761                          * Note, however, that this depends on the order of the
2762                          * extension headers in the ancillary data; the 1st
2763                          * part of the destination options header must appear
2764                          * before the routing header in the ancillary data,
2765                          * too.
2766                          * RFC3542 solved the ambiguity by introducing
2767                          * separate ancillary data or option types.
2768                          */
2769                         if (opt->ip6po_rthdr == NULL)
2770                                 newdest = &opt->ip6po_dest1;
2771                         else
2772                                 newdest = &opt->ip6po_dest2;
2773                         break;
2774                 case IPV6_RTHDRDSTOPTS:
2775                         newdest = &opt->ip6po_dest1;
2776                         break;
2777                 case IPV6_DSTOPTS:
2778                         newdest = &opt->ip6po_dest2;
2779                         break;
2780                 }
2781
2782                 /* turn off the previous option, then set the new option. */
2783                 ip6_clearpktopts(opt, optname);
2784                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
2785                 if (*newdest == NULL)
2786                         return (ENOBUFS);
2787                 bcopy(dest, *newdest, destlen);
2788
2789                 break;
2790         }
2791
2792         case IPV6_2292RTHDR:
2793         case IPV6_RTHDR:
2794         {
2795                 struct ip6_rthdr *rth;
2796                 int rthlen;
2797
2798                 if (len == 0) {
2799                         ip6_clearpktopts(opt, IPV6_RTHDR);
2800                         break;  /* just remove the option */
2801                 }
2802
2803                 /* message length validation */
2804                 if (len < sizeof(struct ip6_rthdr))
2805                         return (EINVAL);
2806                 rth = (struct ip6_rthdr *)buf;
2807                 rthlen = (rth->ip6r_len + 1) << 3;
2808                 if (len != rthlen)
2809                         return (EINVAL);
2810
2811                 switch (rth->ip6r_type) {
2812                 case IPV6_RTHDR_TYPE_0:
2813                         if (rth->ip6r_len == 0) /* must contain one addr */
2814                                 return (EINVAL);
2815                         if (rth->ip6r_len % 2) /* length must be even */
2816                                 return (EINVAL);
2817                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2818                                 return (EINVAL);
2819                         break;
2820                 default:
2821                         return (EINVAL);        /* not supported */
2822                 }
2823
2824                 /* turn off the previous option */
2825                 ip6_clearpktopts(opt, IPV6_RTHDR);
2826                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
2827                 if (opt->ip6po_rthdr == NULL)
2828                         return (ENOBUFS);
2829                 bcopy(rth, opt->ip6po_rthdr, rthlen);
2830
2831                 break;
2832         }
2833
2834         case IPV6_USE_MIN_MTU:
2835                 if (len != sizeof(int))
2836                         return (EINVAL);
2837                 minmtupolicy = *(int *)buf;
2838                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
2839                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
2840                     minmtupolicy != IP6PO_MINMTU_ALL) {
2841                         return (EINVAL);
2842                 }
2843                 opt->ip6po_minmtu = minmtupolicy;
2844                 break;
2845
2846         case IPV6_DONTFRAG:
2847                 if (len != sizeof(int))
2848                         return (EINVAL);
2849
2850                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
2851                         /*
2852                          * we ignore this option for TCP sockets.
2853                          * (RFC3542 leaves this case unspecified.)
2854                          */
2855                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
2856                 } else
2857                         opt->ip6po_flags |= IP6PO_DONTFRAG;
2858                 break;
2859
2860         case IPV6_PREFER_TEMPADDR:
2861                 if (len != sizeof(int))
2862                         return (EINVAL);
2863                 preftemp = *(int *)buf;
2864                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
2865                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
2866                     preftemp != IP6PO_TEMPADDR_PREFER) {
2867                         return (EINVAL);
2868                 }
2869                 opt->ip6po_prefer_tempaddr = preftemp;
2870                 break;
2871
2872         default:
2873                 return (ENOPROTOOPT);
2874         } /* end of switch */
2875
2876         return (0);
2877 }
2878
2879 /*
2880  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2881  * packet to the input queue of a specified interface.  Note that this
2882  * calls the output routine of the loopback "driver", but with an interface
2883  * pointer that might NOT be &loif -- easier than replicating that code here.
2884  */
2885 void
2886 ip6_mloopback(struct ifnet *ifp, const struct mbuf *m)
2887 {
2888         struct mbuf *copym;
2889         struct ip6_hdr *ip6;
2890
2891         copym = m_copy(m, 0, M_COPYALL);
2892         if (copym == NULL)
2893                 return;
2894
2895         /*
2896          * Make sure to deep-copy IPv6 header portion in case the data
2897          * is in an mbuf cluster, so that we can safely override the IPv6
2898          * header portion later.
2899          */
2900         if (!M_WRITABLE(copym) ||
2901             copym->m_len < sizeof(struct ip6_hdr)) {
2902                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
2903                 if (copym == NULL)
2904                         return;
2905         }
2906         ip6 = mtod(copym, struct ip6_hdr *);
2907         /*
2908          * clear embedded scope identifiers if necessary.
2909          * in6_clearscope will touch the addresses only when necessary.
2910          */
2911         in6_clearscope(&ip6->ip6_src);
2912         in6_clearscope(&ip6->ip6_dst);
2913         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
2914                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
2915                     CSUM_PSEUDO_HDR;
2916                 copym->m_pkthdr.csum_data = 0xffff;
2917         }
2918         if_simloop(ifp, copym, AF_INET6, 0);
2919 }
2920
2921 /*
2922  * Chop IPv6 header off from the payload.
2923  */
2924 static int
2925 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
2926 {
2927         struct mbuf *mh;
2928         struct ip6_hdr *ip6;
2929
2930         ip6 = mtod(m, struct ip6_hdr *);
2931         if (m->m_len > sizeof(*ip6)) {
2932                 mh = m_gethdr(M_NOWAIT, MT_DATA);
2933                 if (mh == NULL) {
2934                         m_freem(m);
2935                         return ENOBUFS;
2936                 }
2937                 m_move_pkthdr(mh, m);
2938                 M_ALIGN(mh, sizeof(*ip6));
2939                 m->m_len -= sizeof(*ip6);
2940                 m->m_data += sizeof(*ip6);
2941                 mh->m_next = m;
2942                 m = mh;
2943                 m->m_len = sizeof(*ip6);
2944                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
2945         }
2946         exthdrs->ip6e_ip6 = m;
2947         return 0;
2948 }
2949
2950 /*
2951  * Compute IPv6 extension header length.
2952  */
2953 int
2954 ip6_optlen(struct inpcb *in6p)
2955 {
2956         int len;
2957
2958         if (!in6p->in6p_outputopts)
2959                 return 0;
2960
2961         len = 0;
2962 #define elen(x) \
2963     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
2964
2965         len += elen(in6p->in6p_outputopts->ip6po_hbh);
2966         if (in6p->in6p_outputopts->ip6po_rthdr)
2967                 /* dest1 is valid with rthdr only */
2968                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
2969         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
2970         len += elen(in6p->in6p_outputopts->ip6po_dest2);
2971         return len;
2972 #undef elen
2973 }