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_ipsec.h"
  69 #include "opt_sctp.h"
  70 #include "opt_route.h"
  71 #include "opt_rss.h"
  72
  73 #include <sys/param.h>
  74 #include <sys/kernel.h>
  75 #include <sys/malloc.h>
  76 #include <sys/mbuf.h>
  77 #include <sys/errno.h>
  78 #include <sys/priv.h>
  79 #include <sys/proc.h>
  80 #include <sys/protosw.h>
  81 #include <sys/socket.h>
  82 #include <sys/socketvar.h>
  83 #include <sys/syslog.h>
  84 #include <sys/ucred.h>
  85
  86 #include <machine/in_cksum.h>
  87
  88 #include <net/if.h>
  89 #include <net/if_var.h>
  90 #include <net/netisr.h>
  91 #include <net/route.h>
  92 #include <net/pfil.h>
  93 #include <net/rss_config.h>
  94 #include <net/vnet.h>
  95
  96 #include <netinet/in.h>
  97 #include <netinet/in_var.h>
  98 #include <netinet/ip_var.h>
  99 #include <netinet6/in6_fib.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 MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 138
 139 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 140                            struct ucred *, int);
 141 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 142         struct socket *, struct sockopt *);
 143 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *);
 144 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 145         struct ucred *, int, int, int);
 146
 147 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 148 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 149         struct ip6_frag **);
 150 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 151 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 152 static int ip6_getpmtu(struct route_in6 *, int,
 153         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int);
 154 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 155         u_long *, int *);
 156 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 157 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 158
 159
 160 /*
 161  * Make an extension header from option data.  hp is the source, and
 162  * mp is the destination.
 163  */
 164 #define MAKE_EXTHDR(hp, mp)                                             \
 165     do {                                                                \
 166         if (hp) {                                                       \
 167                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 168                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 169                     ((eh)->ip6e_len + 1) << 3);                         \
 170                 if (error)                                              \
 171                         goto freehdrs;                                  \
 172         }                                                               \
 173     } while (/*CONSTCOND*/ 0)
 174
 175 /*
 176  * Form a chain of extension headers.
 177  * m is the extension header mbuf
 178  * mp is the previous mbuf in the chain
 179  * p is the next header
 180  * i is the type of option.
 181  */
 182 #define MAKE_CHAIN(m, mp, p, i)\
 183     do {\
 184         if (m) {\
 185                 if (!hdrsplit) \
 186                         panic("assumption failed: hdr not split"); \
 187                 *mtod((m), u_char *) = *(p);\
 188                 *(p) = (i);\
 189                 p = mtod((m), u_char *);\
 190                 (m)->m_next = (mp)->m_next;\
 191                 (mp)->m_next = (m);\
 192                 (mp) = (m);\
 193         }\
 194     } while (/*CONSTCOND*/ 0)
 195
 196 void
 197 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 198 {
 199         u_short csum;
 200
 201         csum = in_cksum_skip(m, offset + plen, offset);
 202         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 203                 csum = 0xffff;
 204         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 205
 206         if (offset + sizeof(u_short) > m->m_len) {
 207                 printf("%s: delayed m_pullup, m->len: %d plen %u off %u "
 208                     "csum_flags=%b\n", __func__, m->m_len, plen, offset,
 209                     (int)m->m_pkthdr.csum_flags, CSUM_BITS);
 210                 /*
 211                  * XXX this should not happen, but if it does, the correct
 212                  * behavior may be to insert the checksum in the appropriate
 213                  * next mbuf in the chain.
 214                  */
 215                 return;
 216         }
 217         *(u_short *)(m->m_data + offset) = csum;
 218 }
 219
 220 int
 221 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 222     int mtu, uint32_t id)
 223 {
 224         struct mbuf *m, **mnext, *m_frgpart;
 225         struct ip6_hdr *ip6, *mhip6;
 226         struct ip6_frag *ip6f;
 227         int off;
 228         int error;
 229         int tlen = m0->m_pkthdr.len;
 230
 231         m = m0;
 232         ip6 = mtod(m, struct ip6_hdr *);
 233         mnext = &m->m_nextpkt;
 234
 235         for (off = hlen; off < tlen; off += mtu) {
 236                 m = m_gethdr(M_NOWAIT, MT_DATA);
 237                 if (!m) {
 238                         IP6STAT_INC(ip6s_odropped);
 239                         return (ENOBUFS);
 240                 }
 241                 m->m_flags = m0->m_flags & M_COPYFLAGS;
 242                 *mnext = m;
 243                 mnext = &m->m_nextpkt;
 244                 m->m_data += max_linkhdr;
 245                 mhip6 = mtod(m, struct ip6_hdr *);
 246                 *mhip6 = *ip6;
 247                 m->m_len = sizeof(*mhip6);
 248                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 249                 if (error) {
 250                         IP6STAT_INC(ip6s_odropped);
 251                         return (error);
 252                 }
 253                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 254                 if (off + mtu >= tlen)
 255                         mtu = tlen - off;
 256                 else
 257                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 258                 mhip6->ip6_plen = htons((u_short)(mtu + hlen +
 259                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 260                 if ((m_frgpart = m_copy(m0, off, mtu)) == NULL) {
 261                         IP6STAT_INC(ip6s_odropped);
 262                         return (ENOBUFS);
 263                 }
 264                 m_cat(m, m_frgpart);
 265                 m->m_pkthdr.len = mtu + hlen + sizeof(*ip6f);
 266                 m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum;
 267                 m->m_pkthdr.rcvif = NULL;
 268                 ip6f->ip6f_reserved = 0;
 269                 ip6f->ip6f_ident = id;
 270                 ip6f->ip6f_nxt = nextproto;
 271                 IP6STAT_INC(ip6s_ofragments);
 272                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 273         }
 274
 275         return (0);
 276 }
 277
 278 /*
 279  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 280  * header (with pri, len, nxt, hlim, src, dst).
 281  * This function may modify ver and hlim only.
 282  * The mbuf chain containing the packet will be freed.
 283  * The mbuf opt, if present, will not be freed.
 284  * If route_in6 ro is present and has ro_rt initialized, route lookup would be
 285  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 286  * then result of route lookup is stored in ro->ro_rt.
 287  *
 288  * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
 289  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 290  * which is rt_mtu.
 291  *
 292  * ifpp - XXX: just for statistics
 293  */
 294 /*
 295  * XXX TODO: no flowid is assigned for outbound flows?
 296  */
 297 int
 298 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 299     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 300     struct ifnet **ifpp, struct inpcb *inp)
 301 {
 302         struct ip6_hdr *ip6;
 303         struct ifnet *ifp, *origifp;
 304         struct mbuf *m = m0;
 305         struct mbuf *mprev = NULL;
 306         int hlen, tlen, len;
 307         struct route_in6 ip6route;
 308         struct rtentry *rt = NULL;
 309         struct sockaddr_in6 *dst, src_sa, dst_sa;
 310         struct in6_addr odst;
 311         int error = 0;
 312         struct in6_ifaddr *ia = NULL;
 313         u_long mtu;
 314         int alwaysfrag, dontfrag;
 315         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 316         struct ip6_exthdrs exthdrs;
 317         struct in6_addr src0, dst0;
 318         u_int32_t zone;
 319         struct route_in6 *ro_pmtu = NULL;
 320         int hdrsplit = 0;
 321         int sw_csum, tso;
 322         int needfiblookup;
 323         uint32_t fibnum;
 324         struct m_tag *fwd_tag = NULL;
 325         uint32_t id;
 326
 327         if (inp != NULL) {
 328                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 329                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 330                         /* unconditionally set flowid */
 331                         m->m_pkthdr.flowid = inp->inp_flowid;
 332                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 333                 }
 334         }
 335
 336         bzero(&exthdrs, sizeof(exthdrs));
 337         if (opt) {
 338                 /* Hop-by-Hop options header */
 339                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 340                 /* Destination options header(1st part) */
 341                 if (opt->ip6po_rthdr) {
 342                         /*
 343                          * Destination options header(1st part)
 344                          * This only makes sense with a routing header.
 345                          * See Section 9.2 of RFC 3542.
 346                          * Disabling this part just for MIP6 convenience is
 347                          * a bad idea.  We need to think carefully about a
 348                          * way to make the advanced API coexist with MIP6
 349                          * options, which might automatically be inserted in
 350                          * the kernel.
 351                          */
 352                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 353                 }
 354                 /* Routing header */
 355                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 356                 /* Destination options header(2nd part) */
 357                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 358         }
 359
 360 #ifdef IPSEC
 361         /*
 362          * IPSec checking which handles several cases.
 363          * FAST IPSEC: We re-injected the packet.
 364          * XXX: need scope argument.
 365          */
 366         switch(ip6_ipsec_output(&m, inp, &error))
 367         {
 368         case 1:                 /* Bad packet */
 369                 goto freehdrs;
 370         case -1:                /* IPSec done */
 371                 goto done;
 372         case 0:                 /* No IPSec */
 373         default:
 374                 break;
 375         }
 376 #endif /* IPSEC */
 377
 378         /*
 379          * Calculate the total length of the extension header chain.
 380          * Keep the length of the unfragmentable part for fragmentation.
 381          */
 382         optlen = 0;
 383         if (exthdrs.ip6e_hbh)
 384                 optlen += exthdrs.ip6e_hbh->m_len;
 385         if (exthdrs.ip6e_dest1)
 386                 optlen += exthdrs.ip6e_dest1->m_len;
 387         if (exthdrs.ip6e_rthdr)
 388                 optlen += exthdrs.ip6e_rthdr->m_len;
 389         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 390
 391         /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
 392         if (exthdrs.ip6e_dest2)
 393                 optlen += exthdrs.ip6e_dest2->m_len;
 394
 395         /*
 396          * If there is at least one extension header,
 397          * separate IP6 header from the payload.
 398          */
 399         if (optlen && !hdrsplit) {
 400                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 401                         m = NULL;
 402                         goto freehdrs;
 403                 }
 404                 m = exthdrs.ip6e_ip6;
 405                 hdrsplit++;
 406         }
 407
 408         ip6 = mtod(m, struct ip6_hdr *);
 409
 410         /* adjust mbuf packet header length */
 411         m->m_pkthdr.len += optlen;
 412         plen = m->m_pkthdr.len - sizeof(*ip6);
 413
 414         /* If this is a jumbo payload, insert a jumbo payload option. */
 415         if (plen > IPV6_MAXPACKET) {
 416                 if (!hdrsplit) {
 417                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 418                                 m = NULL;
 419                                 goto freehdrs;
 420                         }
 421                         m = exthdrs.ip6e_ip6;
 422                         hdrsplit++;
 423                 }
 424                 /* adjust pointer */
 425                 ip6 = mtod(m, struct ip6_hdr *);
 426                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 427                         goto freehdrs;
 428                 ip6->ip6_plen = 0;
 429         } else
 430                 ip6->ip6_plen = htons(plen);
 431
 432         /*
 433          * Concatenate headers and fill in next header fields.
 434          * Here we have, on "m"
 435          *      IPv6 payload
 436          * and we insert headers accordingly.  Finally, we should be getting:
 437          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 438          *
 439          * during the header composing process, "m" points to IPv6 header.
 440          * "mprev" points to an extension header prior to esp.
 441          */
 442         u_char *nexthdrp = &ip6->ip6_nxt;
 443         mprev = m;
 444
 445         /*
 446          * we treat dest2 specially.  this makes IPsec processing
 447          * much easier.  the goal here is to make mprev point the
 448          * mbuf prior to dest2.
 449          *
 450          * result: IPv6 dest2 payload
 451          * m and mprev will point to IPv6 header.
 452          */
 453         if (exthdrs.ip6e_dest2) {
 454                 if (!hdrsplit)
 455                         panic("assumption failed: hdr not split");
 456                 exthdrs.ip6e_dest2->m_next = m->m_next;
 457                 m->m_next = exthdrs.ip6e_dest2;
 458                 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 459                 ip6->ip6_nxt = IPPROTO_DSTOPTS;
 460         }
 461
 462         /*
 463          * result: IPv6 hbh dest1 rthdr dest2 payload
 464          * m will point to IPv6 header.  mprev will point to the
 465          * extension header prior to dest2 (rthdr in the above case).
 466          */
 467         MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 468         MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 469                    IPPROTO_DSTOPTS);
 470         MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 471                    IPPROTO_ROUTING);
 472
 473         /*
 474          * If there is a routing header, discard the packet.
 475          */
 476         if (exthdrs.ip6e_rthdr) {
 477                  error = EINVAL;
 478                  goto bad;
 479         }
 480
 481         /* Source address validation */
 482         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 483             (flags & IPV6_UNSPECSRC) == 0) {
 484                 error = EOPNOTSUPP;
 485                 IP6STAT_INC(ip6s_badscope);
 486                 goto bad;
 487         }
 488         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 489                 error = EOPNOTSUPP;
 490                 IP6STAT_INC(ip6s_badscope);
 491                 goto bad;
 492         }
 493
 494         IP6STAT_INC(ip6s_localout);
 495
 496         /*
 497          * Route packet.
 498          */
 499         if (ro == NULL) {
 500                 ro = &ip6route;
 501                 bzero((caddr_t)ro, sizeof(*ro));
 502         } else
 503                 ro->ro_flags |= RT_LLE_CACHE;
 504         ro_pmtu = ro;
 505         if (opt && opt->ip6po_rthdr)
 506                 ro = &opt->ip6po_route;
 507         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 508 #ifdef FLOWTABLE
 509         if (ro->ro_rt == NULL)
 510                 (void )flowtable_lookup(AF_INET6, m, (struct route *)ro);
 511 #endif
 512         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 513 again:
 514         /*
 515          * if specified, try to fill in the traffic class field.
 516          * do not override if a non-zero value is already set.
 517          * we check the diffserv field and the ecn field separately.
 518          */
 519         if (opt && opt->ip6po_tclass >= 0) {
 520                 int mask = 0;
 521
 522                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 523                         mask |= 0xfc;
 524                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 525                         mask |= 0x03;
 526                 if (mask != 0)
 527                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 528         }
 529
 530         /* fill in or override the hop limit field, if necessary. */
 531         if (opt && opt->ip6po_hlim != -1)
 532                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 533         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 534                 if (im6o != NULL)
 535                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 536                 else
 537                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 538         }
 539         /*
 540          * Validate route against routing table additions;
 541          * a better/more specific route might have been added.
 542          * Make sure address family is set in route.
 543          */
 544         if (inp) {
 545                 ro->ro_dst.sin6_family = AF_INET6;
 546                 RT_VALIDATE((struct route *)ro, &inp->inp_rt_cookie, fibnum);
 547         }
 548         if (ro->ro_rt && fwd_tag == NULL && (ro->ro_rt->rt_flags & RTF_UP) &&
 549             ro->ro_dst.sin6_family == AF_INET6 &&
 550             IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 551                 rt = ro->ro_rt;
 552                 ifp = ro->ro_rt->rt_ifp;
 553         } else {
 554                 if (fwd_tag == NULL) {
 555                         bzero(&dst_sa, sizeof(dst_sa));
 556                         dst_sa.sin6_family = AF_INET6;
 557                         dst_sa.sin6_len = sizeof(dst_sa);
 558                         dst_sa.sin6_addr = ip6->ip6_dst;
 559                 }
 560                 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
 561                     &rt, fibnum);
 562                 if (error != 0) {
 563                         if (ifp != NULL)
 564                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 565                         goto bad;
 566                 }
 567         }
 568         if (rt == NULL) {
 569                 /*
 570                  * If in6_selectroute() does not return a route entry,
 571                  * dst may not have been updated.
 572                  */
 573                 *dst = dst_sa;  /* XXX */
 574         }
 575
 576         /*
 577          * then rt (for unicast) and ifp must be non-NULL valid values.
 578          */
 579         if ((flags & IPV6_FORWARDING) == 0) {
 580                 /* XXX: the FORWARDING flag can be set for mrouting. */
 581                 in6_ifstat_inc(ifp, ifs6_out_request);
 582         }
 583         if (rt != NULL) {
 584                 ia = (struct in6_ifaddr *)(rt->rt_ifa);
 585                 counter_u64_add(rt->rt_pksent, 1);
 586         }
 587
 588
 589         /*
 590          * The outgoing interface must be in the zone of source and
 591          * destination addresses.
 592          */
 593         origifp = ifp;
 594
 595         src0 = ip6->ip6_src;
 596         if (in6_setscope(&src0, origifp, &zone))
 597                 goto badscope;
 598         bzero(&src_sa, sizeof(src_sa));
 599         src_sa.sin6_family = AF_INET6;
 600         src_sa.sin6_len = sizeof(src_sa);
 601         src_sa.sin6_addr = ip6->ip6_src;
 602         if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id)
 603                 goto badscope;
 604
 605         dst0 = ip6->ip6_dst;
 606         if (in6_setscope(&dst0, origifp, &zone))
 607                 goto badscope;
 608         /* re-initialize to be sure */
 609         bzero(&dst_sa, sizeof(dst_sa));
 610         dst_sa.sin6_family = AF_INET6;
 611         dst_sa.sin6_len = sizeof(dst_sa);
 612         dst_sa.sin6_addr = ip6->ip6_dst;
 613         if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) {
 614                 goto badscope;
 615         }
 616
 617         /* We should use ia_ifp to support the case of
 618          * sending packets to an address of our own.
 619          */
 620         if (ia != NULL && ia->ia_ifp)
 621                 ifp = ia->ia_ifp;
 622
 623         /* scope check is done. */
 624         goto routefound;
 625
 626   badscope:
 627         IP6STAT_INC(ip6s_badscope);
 628         in6_ifstat_inc(origifp, ifs6_out_discard);
 629         if (error == 0)
 630                 error = EHOSTUNREACH; /* XXX */
 631         goto bad;
 632
 633   routefound:
 634         if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 635                 if (opt && opt->ip6po_nextroute.ro_rt) {
 636                         /*
 637                          * The nexthop is explicitly specified by the
 638                          * application.  We assume the next hop is an IPv6
 639                          * address.
 640                          */
 641                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 642                 }
 643                 else if ((rt->rt_flags & RTF_GATEWAY))
 644                         dst = (struct sockaddr_in6 *)rt->rt_gateway;
 645         }
 646
 647         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 648                 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
 649         } else {
 650                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 651                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 652                 /*
 653                  * Confirm that the outgoing interface supports multicast.
 654                  */
 655                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 656                         IP6STAT_INC(ip6s_noroute);
 657                         in6_ifstat_inc(ifp, ifs6_out_discard);
 658                         error = ENETUNREACH;
 659                         goto bad;
 660                 }
 661                 if ((im6o == NULL && in6_mcast_loop) ||
 662                     (im6o && im6o->im6o_multicast_loop)) {
 663                         /*
 664                          * Loop back multicast datagram if not expressly
 665                          * forbidden to do so, even if we have not joined
 666                          * the address; protocols will filter it later,
 667                          * thus deferring a hash lookup and lock acquisition
 668                          * at the expense of an m_copym().
 669                          */
 670                         ip6_mloopback(ifp, m);
 671                 } else {
 672                         /*
 673                          * If we are acting as a multicast router, perform
 674                          * multicast forwarding as if the packet had just
 675                          * arrived on the interface to which we are about
 676                          * to send.  The multicast forwarding function
 677                          * recursively calls this function, using the
 678                          * IPV6_FORWARDING flag to prevent infinite recursion.
 679                          *
 680                          * Multicasts that are looped back by ip6_mloopback(),
 681                          * above, will be forwarded by the ip6_input() routine,
 682                          * if necessary.
 683                          */
 684                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 685                                 /*
 686                                  * XXX: ip6_mforward expects that rcvif is NULL
 687                                  * when it is called from the originating path.
 688                                  * However, it may not always be the case.
 689                                  */
 690                                 m->m_pkthdr.rcvif = NULL;
 691                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 692                                         m_freem(m);
 693                                         goto done;
 694                                 }
 695                         }
 696                 }
 697                 /*
 698                  * Multicasts with a hoplimit of zero may be looped back,
 699                  * above, but must not be transmitted on a network.
 700                  * Also, multicasts addressed to the loopback interface
 701                  * are not sent -- the above call to ip6_mloopback() will
 702                  * loop back a copy if this host actually belongs to the
 703                  * destination group on the loopback interface.
 704                  */
 705                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 706                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 707                         m_freem(m);
 708                         goto done;
 709                 }
 710         }
 711
 712         /*
 713          * Fill the outgoing inteface to tell the upper layer
 714          * to increment per-interface statistics.
 715          */
 716         if (ifpp)
 717                 *ifpp = ifp;
 718
 719         /* Determine path MTU. */
 720         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 721             &mtu, &alwaysfrag, fibnum)) != 0)
 722                 goto bad;
 723
 724         /*
 725          * The caller of this function may specify to use the minimum MTU
 726          * in some cases.
 727          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 728          * setting.  The logic is a bit complicated; by default, unicast
 729          * packets will follow path MTU while multicast packets will be sent at
 730          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 731          * including unicast ones will be sent at the minimum MTU.  Multicast
 732          * packets will always be sent at the minimum MTU unless
 733          * IP6PO_MINMTU_DISABLE is explicitly specified.
 734          * See RFC 3542 for more details.
 735          */
 736         if (mtu > IPV6_MMTU) {
 737                 if ((flags & IPV6_MINMTU))
 738                         mtu = IPV6_MMTU;
 739                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 740                         mtu = IPV6_MMTU;
 741                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 742                          (opt == NULL ||
 743                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 744                         mtu = IPV6_MMTU;
 745                 }
 746         }
 747
 748         /*
 749          * clear embedded scope identifiers if necessary.
 750          * in6_clearscope will touch the addresses only when necessary.
 751          */
 752         in6_clearscope(&ip6->ip6_src);
 753         in6_clearscope(&ip6->ip6_dst);
 754
 755         /*
 756          * If the outgoing packet contains a hop-by-hop options header,
 757          * it must be examined and processed even by the source node.
 758          * (RFC 2460, section 4.)
 759          */
 760         if (exthdrs.ip6e_hbh) {
 761                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 762                 u_int32_t dummy; /* XXX unused */
 763                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 764
 765 #ifdef DIAGNOSTIC
 766                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 767                         panic("ip6e_hbh is not contiguous");
 768 #endif
 769                 /*
 770                  *  XXX: if we have to send an ICMPv6 error to the sender,
 771                  *       we need the M_LOOP flag since icmp6_error() expects
 772                  *       the IPv6 and the hop-by-hop options header are
 773                  *       contiguous unless the flag is set.
 774                  */
 775                 m->m_flags |= M_LOOP;
 776                 m->m_pkthdr.rcvif = ifp;
 777                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 778                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 779                     &dummy, &plen) < 0) {
 780                         /* m was already freed at this point */
 781                         error = EINVAL;/* better error? */
 782                         goto done;
 783                 }
 784                 m->m_flags &= ~M_LOOP; /* XXX */
 785                 m->m_pkthdr.rcvif = NULL;
 786         }
 787
 788         /* Jump over all PFIL processing if hooks are not active. */
 789         if (!PFIL_HOOKED(&V_inet6_pfil_hook))
 790                 goto passout;
 791
 792         odst = ip6->ip6_dst;
 793         /* Run through list of hooks for output packets. */
 794         error = pfil_run_hooks(&V_inet6_pfil_hook, &m, ifp, PFIL_OUT, inp);
 795         if (error != 0 || m == NULL)
 796                 goto done;
 797         /* adjust pointer */
 798         ip6 = mtod(m, struct ip6_hdr *);
 799
 800         needfiblookup = 0;
 801         /* See if destination IP address was changed by packet filter. */
 802         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
 803                 m->m_flags |= M_SKIP_FIREWALL;
 804                 /* If destination is now ourself drop to ip6_input(). */
 805                 if (in6_localip(&ip6->ip6_dst)) {
 806                         m->m_flags |= M_FASTFWD_OURS;
 807                         if (m->m_pkthdr.rcvif == NULL)
 808                                 m->m_pkthdr.rcvif = V_loif;
 809                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 810                                 m->m_pkthdr.csum_flags |=
 811                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 812                                 m->m_pkthdr.csum_data = 0xffff;
 813                         }
 814 #ifdef SCTP
 815                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 816                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 817 #endif
 818                         error = netisr_queue(NETISR_IPV6, m);
 819                         goto done;
 820                 } else {
 821                         RO_RTFREE(ro);
 822                         needfiblookup = 1; /* Redo the routing table lookup. */
 823                 }
 824         }
 825         /* See if fib was changed by packet filter. */
 826         if (fibnum != M_GETFIB(m)) {
 827                 m->m_flags |= M_SKIP_FIREWALL;
 828                 fibnum = M_GETFIB(m);
 829                 RO_RTFREE(ro);
 830                 needfiblookup = 1;
 831         }
 832         if (needfiblookup)
 833                 goto again;
 834
 835         /* See if local, if yes, send it to netisr. */
 836         if (m->m_flags & M_FASTFWD_OURS) {
 837                 if (m->m_pkthdr.rcvif == NULL)
 838                         m->m_pkthdr.rcvif = V_loif;
 839                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 840                         m->m_pkthdr.csum_flags |=
 841                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 842                         m->m_pkthdr.csum_data = 0xffff;
 843                 }
 844 #ifdef SCTP
 845                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 846                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 847 #endif
 848                 error = netisr_queue(NETISR_IPV6, m);
 849                 goto done;
 850         }
 851         /* Or forward to some other address? */
 852         if ((m->m_flags & M_IP6_NEXTHOP) &&
 853             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 854                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 855                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
 856                 m->m_flags |= M_SKIP_FIREWALL;
 857                 m->m_flags &= ~M_IP6_NEXTHOP;
 858                 m_tag_delete(m, fwd_tag);
 859                 goto again;
 860         }
 861
 862 passout:
 863         /*
 864          * Send the packet to the outgoing interface.
 865          * If necessary, do IPv6 fragmentation before sending.
 866          *
 867          * the logic here is rather complex:
 868          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 869          * 1-a: send as is if tlen <= path mtu
 870          * 1-b: fragment if tlen > path mtu
 871          *
 872          * 2: if user asks us not to fragment (dontfrag == 1)
 873          * 2-a: send as is if tlen <= interface mtu
 874          * 2-b: error if tlen > interface mtu
 875          *
 876          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 877          *      always fragment
 878          *
 879          * 4: if dontfrag == 1 && alwaysfrag == 1
 880          *      error, as we cannot handle this conflicting request
 881          */
 882         sw_csum = m->m_pkthdr.csum_flags;
 883         if (!hdrsplit) {
 884                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
 885                 sw_csum &= ~ifp->if_hwassist;
 886         } else
 887                 tso = 0;
 888         /*
 889          * If we added extension headers, we will not do TSO and calculate the
 890          * checksums ourselves for now.
 891          * XXX-BZ  Need a framework to know when the NIC can handle it, even
 892          * with ext. hdrs.
 893          */
 894         if (sw_csum & CSUM_DELAY_DATA_IPV6) {
 895                 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
 896                 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
 897         }
 898 #ifdef SCTP
 899         if (sw_csum & CSUM_SCTP_IPV6) {
 900                 sw_csum &= ~CSUM_SCTP_IPV6;
 901                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
 902         }
 903 #endif
 904         m->m_pkthdr.csum_flags &= ifp->if_hwassist;
 905         tlen = m->m_pkthdr.len;
 906
 907         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
 908                 dontfrag = 1;
 909         else
 910                 dontfrag = 0;
 911         if (dontfrag && alwaysfrag) {   /* case 4 */
 912                 /* conflicting request - can't transmit */
 913                 error = EMSGSIZE;
 914                 goto bad;
 915         }
 916         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* case 2-b */
 917                 /*
 918                  * Even if the DONTFRAG option is specified, we cannot send the
 919                  * packet when the data length is larger than the MTU of the
 920                  * outgoing interface.
 921                  * Notify the error by sending IPV6_PATHMTU ancillary data if
 922                  * application wanted to know the MTU value. Also return an
 923                  * error code (this is not described in the API spec).
 924                  */
 925                 if (inp != NULL)
 926                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
 927                 error = EMSGSIZE;
 928                 goto bad;
 929         }
 930
 931         /*
 932          * transmit packet without fragmentation
 933          */
 934         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
 935                 struct in6_ifaddr *ia6;
 936
 937                 ip6 = mtod(m, struct ip6_hdr *);
 938                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
 939                 if (ia6) {
 940                         /* Record statistics for this interface address. */
 941                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
 942                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
 943                             m->m_pkthdr.len);
 944                         ifa_free(&ia6->ia_ifa);
 945                 }
 946                 error = nd6_output_ifp(ifp, origifp, m, dst,
 947                     (struct route *)ro);
 948                 goto done;
 949         }
 950
 951         /*
 952          * try to fragment the packet.  case 1-b and 3
 953          */
 954         if (mtu < IPV6_MMTU) {
 955                 /* path MTU cannot be less than IPV6_MMTU */
 956                 error = EMSGSIZE;
 957                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 958                 goto bad;
 959         } else if (ip6->ip6_plen == 0) {
 960                 /* jumbo payload cannot be fragmented */
 961                 error = EMSGSIZE;
 962                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 963                 goto bad;
 964         } else {
 965                 u_char nextproto;
 966
 967                 /*
 968                  * Too large for the destination or interface;
 969                  * fragment if possible.
 970                  * Must be able to put at least 8 bytes per fragment.
 971                  */
 972                 hlen = unfragpartlen;
 973                 if (mtu > IPV6_MAXPACKET)
 974                         mtu = IPV6_MAXPACKET;
 975
 976                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
 977                 if (len < 8) {
 978                         error = EMSGSIZE;
 979                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
 980                         goto bad;
 981                 }
 982
 983                 /*
 984                  * If the interface will not calculate checksums on
 985                  * fragmented packets, then do it here.
 986                  * XXX-BZ handle the hw offloading case.  Need flags.
 987                  */
 988                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 989                         in6_delayed_cksum(m, plen, hlen);
 990                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 991                 }
 992 #ifdef SCTP
 993                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
 994                         sctp_delayed_cksum(m, hlen);
 995                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 996                 }
 997 #endif
 998                 /*
 999                  * Change the next header field of the last header in the
1000                  * unfragmentable part.
1001                  */
1002                 if (exthdrs.ip6e_rthdr) {
1003                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1004                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1005                 } else if (exthdrs.ip6e_dest1) {
1006                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1007                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1008                 } else if (exthdrs.ip6e_hbh) {
1009                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1010                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1011                 } else {
1012                         nextproto = ip6->ip6_nxt;
1013                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1014                 }
1015
1016                 /*
1017                  * Loop through length of segment after first fragment,
1018                  * make new header and copy data of each part and link onto
1019                  * chain.
1020                  */
1021                 m0 = m;
1022                 id = htonl(ip6_randomid());
1023                 if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
1024                         goto sendorfree;
1025
1026                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1027         }
1028
1029         /*
1030          * Remove leading garbages.
1031          */
1032 sendorfree:
1033         m = m0->m_nextpkt;
1034         m0->m_nextpkt = 0;
1035         m_freem(m0);
1036         for (m0 = m; m; m = m0) {
1037                 m0 = m->m_nextpkt;
1038                 m->m_nextpkt = 0;
1039                 if (error == 0) {
1040                         /* Record statistics for this interface address. */
1041                         if (ia) {
1042                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1043                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1044                                     m->m_pkthdr.len);
1045                         }
1046                         error = nd6_output_ifp(ifp, origifp, m, dst,
1047                             (struct route *)ro);
1048                 } else
1049                         m_freem(m);
1050         }
1051
1052         if (error == 0)
1053                 IP6STAT_INC(ip6s_fragmented);
1054
1055 done:
1056         /*
1057          * Release the route if using our private route, or if
1058          * (with flowtable) we don't have our own reference.
1059          */
1060         if (ro == &ip6route || ro->ro_flags & RT_NORTREF)
1061                 RO_RTFREE(ro);
1062         return (error);
1063
1064 freehdrs:
1065         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1066         m_freem(exthdrs.ip6e_dest1);
1067         m_freem(exthdrs.ip6e_rthdr);
1068         m_freem(exthdrs.ip6e_dest2);
1069         /* FALLTHROUGH */
1070 bad:
1071         if (m)
1072                 m_freem(m);
1073         goto done;
1074 }
1075
1076 static int
1077 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1078 {
1079         struct mbuf *m;
1080
1081         if (hlen > MCLBYTES)
1082                 return (ENOBUFS); /* XXX */
1083
1084         if (hlen > MLEN)
1085                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1086         else
1087                 m = m_get(M_NOWAIT, MT_DATA);
1088         if (m == NULL)
1089                 return (ENOBUFS);
1090         m->m_len = hlen;
1091         if (hdr)
1092                 bcopy(hdr, mtod(m, caddr_t), hlen);
1093
1094         *mp = m;
1095         return (0);
1096 }
1097
1098 /*
1099  * Insert jumbo payload option.
1100  */
1101 static int
1102 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1103 {
1104         struct mbuf *mopt;
1105         u_char *optbuf;
1106         u_int32_t v;
1107
1108 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1109
1110         /*
1111          * If there is no hop-by-hop options header, allocate new one.
1112          * If there is one but it doesn't have enough space to store the
1113          * jumbo payload option, allocate a cluster to store the whole options.
1114          * Otherwise, use it to store the options.
1115          */
1116         if (exthdrs->ip6e_hbh == NULL) {
1117                 mopt = m_get(M_NOWAIT, MT_DATA);
1118                 if (mopt == NULL)
1119                         return (ENOBUFS);
1120                 mopt->m_len = JUMBOOPTLEN;
1121                 optbuf = mtod(mopt, u_char *);
1122                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1123                 exthdrs->ip6e_hbh = mopt;
1124         } else {
1125                 struct ip6_hbh *hbh;
1126
1127                 mopt = exthdrs->ip6e_hbh;
1128                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1129                         /*
1130                          * XXX assumption:
1131                          * - exthdrs->ip6e_hbh is not referenced from places
1132                          *   other than exthdrs.
1133                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1134                          */
1135                         int oldoptlen = mopt->m_len;
1136                         struct mbuf *n;
1137
1138                         /*
1139                          * XXX: give up if the whole (new) hbh header does
1140                          * not fit even in an mbuf cluster.
1141                          */
1142                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1143                                 return (ENOBUFS);
1144
1145                         /*
1146                          * As a consequence, we must always prepare a cluster
1147                          * at this point.
1148                          */
1149                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1150                         if (n == NULL)
1151                                 return (ENOBUFS);
1152                         n->m_len = oldoptlen + JUMBOOPTLEN;
1153                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1154                             oldoptlen);
1155                         optbuf = mtod(n, caddr_t) + oldoptlen;
1156                         m_freem(mopt);
1157                         mopt = exthdrs->ip6e_hbh = n;
1158                 } else {
1159                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1160                         mopt->m_len += JUMBOOPTLEN;
1161                 }
1162                 optbuf[0] = IP6OPT_PADN;
1163                 optbuf[1] = 1;
1164
1165                 /*
1166                  * Adjust the header length according to the pad and
1167                  * the jumbo payload option.
1168                  */
1169                 hbh = mtod(mopt, struct ip6_hbh *);
1170                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1171         }
1172
1173         /* fill in the option. */
1174         optbuf[2] = IP6OPT_JUMBO;
1175         optbuf[3] = 4;
1176         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1177         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1178
1179         /* finally, adjust the packet header length */
1180         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1181
1182         return (0);
1183 #undef JUMBOOPTLEN
1184 }
1185
1186 /*
1187  * Insert fragment header and copy unfragmentable header portions.
1188  */
1189 static int
1190 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1191     struct ip6_frag **frghdrp)
1192 {
1193         struct mbuf *n, *mlast;
1194
1195         if (hlen > sizeof(struct ip6_hdr)) {
1196                 n = m_copym(m0, sizeof(struct ip6_hdr),
1197                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1198                 if (n == NULL)
1199                         return (ENOBUFS);
1200                 m->m_next = n;
1201         } else
1202                 n = m;
1203
1204         /* Search for the last mbuf of unfragmentable part. */
1205         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1206                 ;
1207
1208         if (M_WRITABLE(mlast) &&
1209             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1210                 /* use the trailing space of the last mbuf for the fragment hdr */
1211                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1212                     mlast->m_len);
1213                 mlast->m_len += sizeof(struct ip6_frag);
1214                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1215         } else {
1216                 /* allocate a new mbuf for the fragment header */
1217                 struct mbuf *mfrg;
1218
1219                 mfrg = m_get(M_NOWAIT, MT_DATA);
1220                 if (mfrg == NULL)
1221                         return (ENOBUFS);
1222                 mfrg->m_len = sizeof(struct ip6_frag);
1223                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1224                 mlast->m_next = mfrg;
1225         }
1226
1227         return (0);
1228 }
1229
1230 /*
1231  * Calculates IPv6 path mtu for destination @dst.
1232  * Resulting MTU is stored in @mtup.
1233  *
1234  * Returns 0 on success.
1235  */
1236 static int
1237 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1238 {
1239         struct nhop6_extended nh6;
1240         struct in6_addr kdst;
1241         uint32_t scopeid;
1242         struct ifnet *ifp;
1243         u_long mtu;
1244         int error;
1245
1246         in6_splitscope(dst, &kdst, &scopeid);
1247         if (fib6_lookup_nh_ext(fibnum, &kdst, scopeid, NHR_REF, 0, &nh6) != 0)
1248                 return (EHOSTUNREACH);
1249
1250         ifp = nh6.nh_ifp;
1251         mtu = nh6.nh_mtu;
1252
1253         error = ip6_calcmtu(ifp, dst, mtu, mtup, NULL);
1254         fib6_free_nh_ext(fibnum, &nh6);
1255
1256         return (error);
1257 }
1258
1259 /*
1260  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1261  * and cached data in @ro_pmtu.
1262  * MTU from (successful) route lookup is saved (along with dst)
1263  * inside @ro_pmtu to avoid subsequent route lookups after packet
1264  * filter processing.
1265  *
1266  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1267  * Returns 0 on success.
1268  */
1269 static int
1270 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1271     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1272     int *alwaysfragp, u_int fibnum)
1273 {
1274         struct nhop6_basic nh6;
1275         struct in6_addr kdst;
1276         uint32_t scopeid;
1277         struct sockaddr_in6 *sa6_dst;
1278         u_long mtu;
1279
1280         mtu = 0;
1281         if (do_lookup) {
1282
1283                 /*
1284                  * Here ro_pmtu has final destination address, while
1285                  * ro might represent immediate destination.
1286                  * Use ro_pmtu destination since mtu might differ.
1287                  */
1288                 sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1289                 if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1290                         ro_pmtu->ro_mtu = 0;
1291
1292                 if (ro_pmtu->ro_mtu == 0) {
1293                         bzero(sa6_dst, sizeof(*sa6_dst));
1294                         sa6_dst->sin6_family = AF_INET6;
1295                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1296                         sa6_dst->sin6_addr = *dst;
1297
1298                         in6_splitscope(dst, &kdst, &scopeid);
1299                         if (fib6_lookup_nh_basic(fibnum, &kdst, scopeid, 0, 0,
1300                             &nh6) == 0)
1301                                 ro_pmtu->ro_mtu = nh6.nh_mtu;
1302                 }
1303
1304                 mtu = ro_pmtu->ro_mtu;
1305         }
1306
1307         if (ro_pmtu->ro_rt)
1308                 mtu = ro_pmtu->ro_rt->rt_mtu;
1309
1310         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp));
1311 }
1312
1313 /*
1314  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1315  * hostcache data for @dst.
1316  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1317  *
1318  * Returns 0 on success.
1319  */
1320 static int
1321 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1322     u_long *mtup, int *alwaysfragp)
1323 {
1324         u_long mtu = 0;
1325         int alwaysfrag = 0;
1326         int error = 0;
1327
1328         if (rt_mtu > 0) {
1329                 u_int32_t ifmtu;
1330                 struct in_conninfo inc;
1331
1332                 bzero(&inc, sizeof(inc));
1333                 inc.inc_flags |= INC_ISIPV6;
1334                 inc.inc6_faddr = *dst;
1335
1336                 ifmtu = IN6_LINKMTU(ifp);
1337                 mtu = tcp_hc_getmtu(&inc);
1338                 if (mtu)
1339                         mtu = min(mtu, rt_mtu);
1340                 else
1341                         mtu = rt_mtu;
1342                 if (mtu == 0)
1343                         mtu = ifmtu;
1344                 else if (mtu < IPV6_MMTU) {
1345                         /*
1346                          * RFC2460 section 5, last paragraph:
1347                          * if we record ICMPv6 too big message with
1348                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1349                          * or smaller, with framgent header attached.
1350                          * (fragment header is needed regardless from the
1351                          * packet size, for translators to identify packets)
1352                          */
1353                         alwaysfrag = 1;
1354                         mtu = IPV6_MMTU;
1355                 }
1356         } else if (ifp) {
1357                 mtu = IN6_LINKMTU(ifp);
1358         } else
1359                 error = EHOSTUNREACH; /* XXX */
1360
1361         *mtup = mtu;
1362         if (alwaysfragp)
1363                 *alwaysfragp = alwaysfrag;
1364         return (error);
1365 }
1366
1367 /*
1368  * IP6 socket option processing.
1369  */
1370 int
1371 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1372 {
1373         int optdatalen, uproto;
1374         void *optdata;
1375         struct inpcb *in6p = sotoinpcb(so);
1376         int error, optval;
1377         int level, op, optname;
1378         int optlen;
1379         struct thread *td;
1380 #ifdef  RSS
1381         uint32_t rss_bucket;
1382         int retval;
1383 #endif
1384
1385         level = sopt->sopt_level;
1386         op = sopt->sopt_dir;
1387         optname = sopt->sopt_name;
1388         optlen = sopt->sopt_valsize;
1389         td = sopt->sopt_td;
1390         error = 0;
1391         optval = 0;
1392         uproto = (int)so->so_proto->pr_protocol;
1393
1394         if (level != IPPROTO_IPV6) {
1395                 error = EINVAL;
1396
1397                 if (sopt->sopt_level == SOL_SOCKET &&
1398                     sopt->sopt_dir == SOPT_SET) {
1399                         switch (sopt->sopt_name) {
1400                         case SO_REUSEADDR:
1401                                 INP_WLOCK(in6p);
1402                                 if ((so->so_options & SO_REUSEADDR) != 0)
1403                                         in6p->inp_flags2 |= INP_REUSEADDR;
1404                                 else
1405                                         in6p->inp_flags2 &= ~INP_REUSEADDR;
1406                                 INP_WUNLOCK(in6p);
1407                                 error = 0;
1408                                 break;
1409                         case SO_REUSEPORT:
1410                                 INP_WLOCK(in6p);
1411                                 if ((so->so_options & SO_REUSEPORT) != 0)
1412                                         in6p->inp_flags2 |= INP_REUSEPORT;
1413                                 else
1414                                         in6p->inp_flags2 &= ~INP_REUSEPORT;
1415                                 INP_WUNLOCK(in6p);
1416                                 error = 0;
1417                                 break;
1418                         case SO_SETFIB:
1419                                 INP_WLOCK(in6p);
1420                                 in6p->inp_inc.inc_fibnum = so->so_fibnum;
1421                                 INP_WUNLOCK(in6p);
1422                                 error = 0;
1423                                 break;
1424                         default:
1425                                 break;
1426                         }
1427                 }
1428         } else {                /* level == IPPROTO_IPV6 */
1429                 switch (op) {
1430
1431                 case SOPT_SET:
1432                         switch (optname) {
1433                         case IPV6_2292PKTOPTIONS:
1434 #ifdef IPV6_PKTOPTIONS
1435                         case IPV6_PKTOPTIONS:
1436 #endif
1437                         {
1438                                 struct mbuf *m;
1439
1440                                 error = soopt_getm(sopt, &m); /* XXX */
1441                                 if (error != 0)
1442                                         break;
1443                                 error = soopt_mcopyin(sopt, m); /* XXX */
1444                                 if (error != 0)
1445                                         break;
1446                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1447                                                     m, so, sopt);
1448                                 m_freem(m); /* XXX */
1449                                 break;
1450                         }
1451
1452                         /*
1453                          * Use of some Hop-by-Hop options or some
1454                          * Destination options, might require special
1455                          * privilege.  That is, normal applications
1456                          * (without special privilege) might be forbidden
1457                          * from setting certain options in outgoing packets,
1458                          * and might never see certain options in received
1459                          * packets. [RFC 2292 Section 6]
1460                          * KAME specific note:
1461                          *  KAME prevents non-privileged users from sending or
1462                          *  receiving ANY hbh/dst options in order to avoid
1463                          *  overhead of parsing options in the kernel.
1464                          */
1465                         case IPV6_RECVHOPOPTS:
1466                         case IPV6_RECVDSTOPTS:
1467                         case IPV6_RECVRTHDRDSTOPTS:
1468                                 if (td != NULL) {
1469                                         error = priv_check(td,
1470                                             PRIV_NETINET_SETHDROPTS);
1471                                         if (error)
1472                                                 break;
1473                                 }
1474                                 /* FALLTHROUGH */
1475                         case IPV6_UNICAST_HOPS:
1476                         case IPV6_HOPLIMIT:
1477
1478                         case IPV6_RECVPKTINFO:
1479                         case IPV6_RECVHOPLIMIT:
1480                         case IPV6_RECVRTHDR:
1481                         case IPV6_RECVPATHMTU:
1482                         case IPV6_RECVTCLASS:
1483                         case IPV6_RECVFLOWID:
1484 #ifdef  RSS
1485                         case IPV6_RECVRSSBUCKETID:
1486 #endif
1487                         case IPV6_V6ONLY:
1488                         case IPV6_AUTOFLOWLABEL:
1489                         case IPV6_BINDANY:
1490                         case IPV6_BINDMULTI:
1491 #ifdef  RSS
1492                         case IPV6_RSS_LISTEN_BUCKET:
1493 #endif
1494                                 if (optname == IPV6_BINDANY && td != NULL) {
1495                                         error = priv_check(td,
1496                                             PRIV_NETINET_BINDANY);
1497                                         if (error)
1498                                                 break;
1499                                 }
1500
1501                                 if (optlen != sizeof(int)) {
1502                                         error = EINVAL;
1503                                         break;
1504                                 }
1505                                 error = sooptcopyin(sopt, &optval,
1506                                         sizeof optval, sizeof optval);
1507                                 if (error)
1508                                         break;
1509                                 switch (optname) {
1510
1511                                 case IPV6_UNICAST_HOPS:
1512                                         if (optval < -1 || optval >= 256)
1513                                                 error = EINVAL;
1514                                         else {
1515                                                 /* -1 = kernel default */
1516                                                 in6p->in6p_hops = optval;
1517                                                 if ((in6p->inp_vflag &
1518                                                      INP_IPV4) != 0)
1519                                                         in6p->inp_ip_ttl = optval;
1520                                         }
1521                                         break;
1522 #define OPTSET(bit) \
1523 do { \
1524         INP_WLOCK(in6p); \
1525         if (optval) \
1526                 in6p->inp_flags |= (bit); \
1527         else \
1528                 in6p->inp_flags &= ~(bit); \
1529         INP_WUNLOCK(in6p); \
1530 } while (/*CONSTCOND*/ 0)
1531 #define OPTSET2292(bit) \
1532 do { \
1533         INP_WLOCK(in6p); \
1534         in6p->inp_flags |= IN6P_RFC2292; \
1535         if (optval) \
1536                 in6p->inp_flags |= (bit); \
1537         else \
1538                 in6p->inp_flags &= ~(bit); \
1539         INP_WUNLOCK(in6p); \
1540 } while (/*CONSTCOND*/ 0)
1541 #define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0)
1542
1543 #define OPTSET2(bit, val) do {                                          \
1544         INP_WLOCK(in6p);                                                \
1545         if (val)                                                        \
1546                 in6p->inp_flags2 |= bit;                                \
1547         else                                                            \
1548                 in6p->inp_flags2 &= ~bit;                               \
1549         INP_WUNLOCK(in6p);                                              \
1550 } while (0)
1551 #define OPTBIT2(bit) (in6p->inp_flags2 & (bit) ? 1 : 0)
1552
1553                                 case IPV6_RECVPKTINFO:
1554                                         /* cannot mix with RFC2292 */
1555                                         if (OPTBIT(IN6P_RFC2292)) {
1556                                                 error = EINVAL;
1557                                                 break;
1558                                         }
1559                                         OPTSET(IN6P_PKTINFO);
1560                                         break;
1561
1562                                 case IPV6_HOPLIMIT:
1563                                 {
1564                                         struct ip6_pktopts **optp;
1565
1566                                         /* cannot mix with RFC2292 */
1567                                         if (OPTBIT(IN6P_RFC2292)) {
1568                                                 error = EINVAL;
1569                                                 break;
1570                                         }
1571                                         optp = &in6p->in6p_outputopts;
1572                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1573                                             (u_char *)&optval, sizeof(optval),
1574                                             optp, (td != NULL) ? td->td_ucred :
1575                                             NULL, uproto);
1576                                         break;
1577                                 }
1578
1579                                 case IPV6_RECVHOPLIMIT:
1580                                         /* cannot mix with RFC2292 */
1581                                         if (OPTBIT(IN6P_RFC2292)) {
1582                                                 error = EINVAL;
1583                                                 break;
1584                                         }
1585                                         OPTSET(IN6P_HOPLIMIT);
1586                                         break;
1587
1588                                 case IPV6_RECVHOPOPTS:
1589                                         /* cannot mix with RFC2292 */
1590                                         if (OPTBIT(IN6P_RFC2292)) {
1591                                                 error = EINVAL;
1592                                                 break;
1593                                         }
1594                                         OPTSET(IN6P_HOPOPTS);
1595                                         break;
1596
1597                                 case IPV6_RECVDSTOPTS:
1598                                         /* cannot mix with RFC2292 */
1599                                         if (OPTBIT(IN6P_RFC2292)) {
1600                                                 error = EINVAL;
1601                                                 break;
1602                                         }
1603                                         OPTSET(IN6P_DSTOPTS);
1604                                         break;
1605
1606                                 case IPV6_RECVRTHDRDSTOPTS:
1607                                         /* cannot mix with RFC2292 */
1608                                         if (OPTBIT(IN6P_RFC2292)) {
1609                                                 error = EINVAL;
1610                                                 break;
1611                                         }
1612                                         OPTSET(IN6P_RTHDRDSTOPTS);
1613                                         break;
1614
1615                                 case IPV6_RECVRTHDR:
1616                                         /* cannot mix with RFC2292 */
1617                                         if (OPTBIT(IN6P_RFC2292)) {
1618                                                 error = EINVAL;
1619                                                 break;
1620                                         }
1621                                         OPTSET(IN6P_RTHDR);
1622                                         break;
1623
1624                                 case IPV6_RECVPATHMTU:
1625                                         /*
1626                                          * We ignore this option for TCP
1627                                          * sockets.
1628                                          * (RFC3542 leaves this case
1629                                          * unspecified.)
1630                                          */
1631                                         if (uproto != IPPROTO_TCP)
1632                                                 OPTSET(IN6P_MTU);
1633                                         break;
1634
1635                                 case IPV6_RECVFLOWID:
1636                                         OPTSET2(INP_RECVFLOWID, optval);
1637                                         break;
1638
1639 #ifdef  RSS
1640                                 case IPV6_RECVRSSBUCKETID:
1641                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1642                                         break;
1643 #endif
1644
1645                                 case IPV6_V6ONLY:
1646                                         /*
1647                                          * make setsockopt(IPV6_V6ONLY)
1648                                          * available only prior to bind(2).
1649                                          * see ipng mailing list, Jun 22 2001.
1650                                          */
1651                                         if (in6p->inp_lport ||
1652                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
1653                                                 error = EINVAL;
1654                                                 break;
1655                                         }
1656                                         OPTSET(IN6P_IPV6_V6ONLY);
1657                                         if (optval)
1658                                                 in6p->inp_vflag &= ~INP_IPV4;
1659                                         else
1660                                                 in6p->inp_vflag |= INP_IPV4;
1661                                         break;
1662                                 case IPV6_RECVTCLASS:
1663                                         /* cannot mix with RFC2292 XXX */
1664                                         if (OPTBIT(IN6P_RFC2292)) {
1665                                                 error = EINVAL;
1666                                                 break;
1667                                         }
1668                                         OPTSET(IN6P_TCLASS);
1669                                         break;
1670                                 case IPV6_AUTOFLOWLABEL:
1671                                         OPTSET(IN6P_AUTOFLOWLABEL);
1672                                         break;
1673
1674                                 case IPV6_BINDANY:
1675                                         OPTSET(INP_BINDANY);
1676                                         break;
1677
1678                                 case IPV6_BINDMULTI:
1679                                         OPTSET2(INP_BINDMULTI, optval);
1680                                         break;
1681 #ifdef  RSS
1682                                 case IPV6_RSS_LISTEN_BUCKET:
1683                                         if ((optval >= 0) &&
1684                                             (optval < rss_getnumbuckets())) {
1685                                                 in6p->inp_rss_listen_bucket = optval;
1686                                                 OPTSET2(INP_RSS_BUCKET_SET, 1);
1687                                         } else {
1688                                                 error = EINVAL;
1689                                         }
1690                                         break;
1691 #endif
1692                                 }
1693                                 break;
1694
1695                         case IPV6_TCLASS:
1696                         case IPV6_DONTFRAG:
1697                         case IPV6_USE_MIN_MTU:
1698                         case IPV6_PREFER_TEMPADDR:
1699                                 if (optlen != sizeof(optval)) {
1700                                         error = EINVAL;
1701                                         break;
1702                                 }
1703                                 error = sooptcopyin(sopt, &optval,
1704                                         sizeof optval, sizeof optval);
1705                                 if (error)
1706                                         break;
1707                                 {
1708                                         struct ip6_pktopts **optp;
1709                                         optp = &in6p->in6p_outputopts;
1710                                         error = ip6_pcbopt(optname,
1711                                             (u_char *)&optval, sizeof(optval),
1712                                             optp, (td != NULL) ? td->td_ucred :
1713                                             NULL, uproto);
1714                                         break;
1715                                 }
1716
1717                         case IPV6_2292PKTINFO:
1718                         case IPV6_2292HOPLIMIT:
1719                         case IPV6_2292HOPOPTS:
1720                         case IPV6_2292DSTOPTS:
1721                         case IPV6_2292RTHDR:
1722                                 /* RFC 2292 */
1723                                 if (optlen != sizeof(int)) {
1724                                         error = EINVAL;
1725                                         break;
1726                                 }
1727                                 error = sooptcopyin(sopt, &optval,
1728                                         sizeof optval, sizeof optval);
1729                                 if (error)
1730                                         break;
1731                                 switch (optname) {
1732                                 case IPV6_2292PKTINFO:
1733                                         OPTSET2292(IN6P_PKTINFO);
1734                                         break;
1735                                 case IPV6_2292HOPLIMIT:
1736                                         OPTSET2292(IN6P_HOPLIMIT);
1737                                         break;
1738                                 case IPV6_2292HOPOPTS:
1739                                         /*
1740                                          * Check super-user privilege.
1741                                          * See comments for IPV6_RECVHOPOPTS.
1742                                          */
1743                                         if (td != NULL) {
1744                                                 error = priv_check(td,
1745                                                     PRIV_NETINET_SETHDROPTS);
1746                                                 if (error)
1747                                                         return (error);
1748                                         }
1749                                         OPTSET2292(IN6P_HOPOPTS);
1750                                         break;
1751                                 case IPV6_2292DSTOPTS:
1752                                         if (td != NULL) {
1753                                                 error = priv_check(td,
1754                                                     PRIV_NETINET_SETHDROPTS);
1755                                                 if (error)
1756                                                         return (error);
1757                                         }
1758                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1759                                         break;
1760                                 case IPV6_2292RTHDR:
1761                                         OPTSET2292(IN6P_RTHDR);
1762                                         break;
1763                                 }
1764                                 break;
1765                         case IPV6_PKTINFO:
1766                         case IPV6_HOPOPTS:
1767                         case IPV6_RTHDR:
1768                         case IPV6_DSTOPTS:
1769                         case IPV6_RTHDRDSTOPTS:
1770                         case IPV6_NEXTHOP:
1771                         {
1772                                 /* new advanced API (RFC3542) */
1773                                 u_char *optbuf;
1774                                 u_char optbuf_storage[MCLBYTES];
1775                                 int optlen;
1776                                 struct ip6_pktopts **optp;
1777
1778                                 /* cannot mix with RFC2292 */
1779                                 if (OPTBIT(IN6P_RFC2292)) {
1780                                         error = EINVAL;
1781                                         break;
1782                                 }
1783
1784                                 /*
1785                                  * We only ensure valsize is not too large
1786                                  * here.  Further validation will be done
1787                                  * later.
1788                                  */
1789                                 error = sooptcopyin(sopt, optbuf_storage,
1790                                     sizeof(optbuf_storage), 0);
1791                                 if (error)
1792                                         break;
1793                                 optlen = sopt->sopt_valsize;
1794                                 optbuf = optbuf_storage;
1795                                 optp = &in6p->in6p_outputopts;
1796                                 error = ip6_pcbopt(optname, optbuf, optlen,
1797                                     optp, (td != NULL) ? td->td_ucred : NULL,
1798                                     uproto);
1799                                 break;
1800                         }
1801 #undef OPTSET
1802
1803                         case IPV6_MULTICAST_IF:
1804                         case IPV6_MULTICAST_HOPS:
1805                         case IPV6_MULTICAST_LOOP:
1806                         case IPV6_JOIN_GROUP:
1807                         case IPV6_LEAVE_GROUP:
1808                         case IPV6_MSFILTER:
1809                         case MCAST_BLOCK_SOURCE:
1810                         case MCAST_UNBLOCK_SOURCE:
1811                         case MCAST_JOIN_GROUP:
1812                         case MCAST_LEAVE_GROUP:
1813                         case MCAST_JOIN_SOURCE_GROUP:
1814                         case MCAST_LEAVE_SOURCE_GROUP:
1815                                 error = ip6_setmoptions(in6p, sopt);
1816                                 break;
1817
1818                         case IPV6_PORTRANGE:
1819                                 error = sooptcopyin(sopt, &optval,
1820                                     sizeof optval, sizeof optval);
1821                                 if (error)
1822                                         break;
1823
1824                                 INP_WLOCK(in6p);
1825                                 switch (optval) {
1826                                 case IPV6_PORTRANGE_DEFAULT:
1827                                         in6p->inp_flags &= ~(INP_LOWPORT);
1828                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1829                                         break;
1830
1831                                 case IPV6_PORTRANGE_HIGH:
1832                                         in6p->inp_flags &= ~(INP_LOWPORT);
1833                                         in6p->inp_flags |= INP_HIGHPORT;
1834                                         break;
1835
1836                                 case IPV6_PORTRANGE_LOW:
1837                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1838                                         in6p->inp_flags |= INP_LOWPORT;
1839                                         break;
1840
1841                                 default:
1842                                         error = EINVAL;
1843                                         break;
1844                                 }
1845                                 INP_WUNLOCK(in6p);
1846                                 break;
1847
1848 #ifdef IPSEC
1849                         case IPV6_IPSEC_POLICY:
1850                         {
1851                                 caddr_t req;
1852                                 struct mbuf *m;
1853
1854                                 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1855                                         break;
1856                                 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1857                                         break;
1858                                 req = mtod(m, caddr_t);
1859                                 error = ipsec_set_policy(in6p, optname, req,
1860                                     m->m_len, (sopt->sopt_td != NULL) ?
1861                                     sopt->sopt_td->td_ucred : NULL);
1862                                 m_freem(m);
1863                                 break;
1864                         }
1865 #endif /* IPSEC */
1866
1867                         default:
1868                                 error = ENOPROTOOPT;
1869                                 break;
1870                         }
1871                         break;
1872
1873                 case SOPT_GET:
1874                         switch (optname) {
1875
1876                         case IPV6_2292PKTOPTIONS:
1877 #ifdef IPV6_PKTOPTIONS
1878                         case IPV6_PKTOPTIONS:
1879 #endif
1880                                 /*
1881                                  * RFC3542 (effectively) deprecated the
1882                                  * semantics of the 2292-style pktoptions.
1883                                  * Since it was not reliable in nature (i.e.,
1884                                  * applications had to expect the lack of some
1885                                  * information after all), it would make sense
1886                                  * to simplify this part by always returning
1887                                  * empty data.
1888                                  */
1889                                 sopt->sopt_valsize = 0;
1890                                 break;
1891
1892                         case IPV6_RECVHOPOPTS:
1893                         case IPV6_RECVDSTOPTS:
1894                         case IPV6_RECVRTHDRDSTOPTS:
1895                         case IPV6_UNICAST_HOPS:
1896                         case IPV6_RECVPKTINFO:
1897                         case IPV6_RECVHOPLIMIT:
1898                         case IPV6_RECVRTHDR:
1899                         case IPV6_RECVPATHMTU:
1900
1901                         case IPV6_V6ONLY:
1902                         case IPV6_PORTRANGE:
1903                         case IPV6_RECVTCLASS:
1904                         case IPV6_AUTOFLOWLABEL:
1905                         case IPV6_BINDANY:
1906                         case IPV6_FLOWID:
1907                         case IPV6_FLOWTYPE:
1908                         case IPV6_RECVFLOWID:
1909 #ifdef  RSS
1910                         case IPV6_RSSBUCKETID:
1911                         case IPV6_RECVRSSBUCKETID:
1912 #endif
1913                         case IPV6_BINDMULTI:
1914                                 switch (optname) {
1915
1916                                 case IPV6_RECVHOPOPTS:
1917                                         optval = OPTBIT(IN6P_HOPOPTS);
1918                                         break;
1919
1920                                 case IPV6_RECVDSTOPTS:
1921                                         optval = OPTBIT(IN6P_DSTOPTS);
1922                                         break;
1923
1924                                 case IPV6_RECVRTHDRDSTOPTS:
1925                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
1926                                         break;
1927
1928                                 case IPV6_UNICAST_HOPS:
1929                                         optval = in6p->in6p_hops;
1930                                         break;
1931
1932                                 case IPV6_RECVPKTINFO:
1933                                         optval = OPTBIT(IN6P_PKTINFO);
1934                                         break;
1935
1936                                 case IPV6_RECVHOPLIMIT:
1937                                         optval = OPTBIT(IN6P_HOPLIMIT);
1938                                         break;
1939
1940                                 case IPV6_RECVRTHDR:
1941                                         optval = OPTBIT(IN6P_RTHDR);
1942                                         break;
1943
1944                                 case IPV6_RECVPATHMTU:
1945                                         optval = OPTBIT(IN6P_MTU);
1946                                         break;
1947
1948                                 case IPV6_V6ONLY:
1949                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
1950                                         break;
1951
1952                                 case IPV6_PORTRANGE:
1953                                     {
1954                                         int flags;
1955                                         flags = in6p->inp_flags;
1956                                         if (flags & INP_HIGHPORT)
1957                                                 optval = IPV6_PORTRANGE_HIGH;
1958                                         else if (flags & INP_LOWPORT)
1959                                                 optval = IPV6_PORTRANGE_LOW;
1960                                         else
1961                                                 optval = 0;
1962                                         break;
1963                                     }
1964                                 case IPV6_RECVTCLASS:
1965                                         optval = OPTBIT(IN6P_TCLASS);
1966                                         break;
1967
1968                                 case IPV6_AUTOFLOWLABEL:
1969                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
1970                                         break;
1971
1972                                 case IPV6_BINDANY:
1973                                         optval = OPTBIT(INP_BINDANY);
1974                                         break;
1975
1976                                 case IPV6_FLOWID:
1977                                         optval = in6p->inp_flowid;
1978                                         break;
1979
1980                                 case IPV6_FLOWTYPE:
1981                                         optval = in6p->inp_flowtype;
1982                                         break;
1983
1984                                 case IPV6_RECVFLOWID:
1985                                         optval = OPTBIT2(INP_RECVFLOWID);
1986                                         break;
1987 #ifdef  RSS
1988                                 case IPV6_RSSBUCKETID:
1989                                         retval =
1990                                             rss_hash2bucket(in6p->inp_flowid,
1991                                             in6p->inp_flowtype,
1992                                             &rss_bucket);
1993                                         if (retval == 0)
1994                                                 optval = rss_bucket;
1995                                         else
1996                                                 error = EINVAL;
1997                                         break;
1998
1999                                 case IPV6_RECVRSSBUCKETID:
2000                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2001                                         break;
2002 #endif
2003
2004                                 case IPV6_BINDMULTI:
2005                                         optval = OPTBIT2(INP_BINDMULTI);
2006                                         break;
2007
2008                                 }
2009                                 if (error)
2010                                         break;
2011                                 error = sooptcopyout(sopt, &optval,
2012                                         sizeof optval);
2013                                 break;
2014
2015                         case IPV6_PATHMTU:
2016                         {
2017                                 u_long pmtu = 0;
2018                                 struct ip6_mtuinfo mtuinfo;
2019
2020                                 if (!(so->so_state & SS_ISCONNECTED))
2021                                         return (ENOTCONN);
2022                                 /*
2023                                  * XXX: we dot not consider the case of source
2024                                  * routing, or optional information to specify
2025                                  * the outgoing interface.
2026                                  */
2027                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2028                                     &in6p->in6p_faddr, &pmtu);
2029                                 if (error)
2030                                         break;
2031                                 if (pmtu > IPV6_MAXPACKET)
2032                                         pmtu = IPV6_MAXPACKET;
2033
2034                                 bzero(&mtuinfo, sizeof(mtuinfo));
2035                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2036                                 optdata = (void *)&mtuinfo;
2037                                 optdatalen = sizeof(mtuinfo);
2038                                 error = sooptcopyout(sopt, optdata,
2039                                     optdatalen);
2040                                 break;
2041                         }
2042
2043                         case IPV6_2292PKTINFO:
2044                         case IPV6_2292HOPLIMIT:
2045                         case IPV6_2292HOPOPTS:
2046                         case IPV6_2292RTHDR:
2047                         case IPV6_2292DSTOPTS:
2048                                 switch (optname) {
2049                                 case IPV6_2292PKTINFO:
2050                                         optval = OPTBIT(IN6P_PKTINFO);
2051                                         break;
2052                                 case IPV6_2292HOPLIMIT:
2053                                         optval = OPTBIT(IN6P_HOPLIMIT);
2054                                         break;
2055                                 case IPV6_2292HOPOPTS:
2056                                         optval = OPTBIT(IN6P_HOPOPTS);
2057                                         break;
2058                                 case IPV6_2292RTHDR:
2059                                         optval = OPTBIT(IN6P_RTHDR);
2060                                         break;
2061                                 case IPV6_2292DSTOPTS:
2062                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2063                                         break;
2064                                 }
2065                                 error = sooptcopyout(sopt, &optval,
2066                                     sizeof optval);
2067                                 break;
2068                         case IPV6_PKTINFO:
2069                         case IPV6_HOPOPTS:
2070                         case IPV6_RTHDR:
2071                         case IPV6_DSTOPTS:
2072                         case IPV6_RTHDRDSTOPTS:
2073                         case IPV6_NEXTHOP:
2074                         case IPV6_TCLASS:
2075                         case IPV6_DONTFRAG:
2076                         case IPV6_USE_MIN_MTU:
2077                         case IPV6_PREFER_TEMPADDR:
2078                                 error = ip6_getpcbopt(in6p->in6p_outputopts,
2079                                     optname, sopt);
2080                                 break;
2081
2082                         case IPV6_MULTICAST_IF:
2083                         case IPV6_MULTICAST_HOPS:
2084                         case IPV6_MULTICAST_LOOP:
2085                         case IPV6_MSFILTER:
2086                                 error = ip6_getmoptions(in6p, sopt);
2087                                 break;
2088
2089 #ifdef IPSEC
2090                         case IPV6_IPSEC_POLICY:
2091                           {
2092                                 caddr_t req = NULL;
2093                                 size_t len = 0;
2094                                 struct mbuf *m = NULL;
2095                                 struct mbuf **mp = &m;
2096                                 size_t ovalsize = sopt->sopt_valsize;
2097                                 caddr_t oval = (caddr_t)sopt->sopt_val;
2098
2099                                 error = soopt_getm(sopt, &m); /* XXX */
2100                                 if (error != 0)
2101                                         break;
2102                                 error = soopt_mcopyin(sopt, m); /* XXX */
2103                                 if (error != 0)
2104                                         break;
2105                                 sopt->sopt_valsize = ovalsize;
2106                                 sopt->sopt_val = oval;
2107                                 if (m) {
2108                                         req = mtod(m, caddr_t);
2109                                         len = m->m_len;
2110                                 }
2111                                 error = ipsec_get_policy(in6p, req, len, mp);
2112                                 if (error == 0)
2113                                         error = soopt_mcopyout(sopt, m); /* XXX */
2114                                 if (error == 0 && m)
2115                                         m_freem(m);
2116                                 break;
2117                           }
2118 #endif /* IPSEC */
2119
2120                         default:
2121                                 error = ENOPROTOOPT;
2122                                 break;
2123                         }
2124                         break;
2125                 }
2126         }
2127         return (error);
2128 }
2129
2130 int
2131 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2132 {
2133         int error = 0, optval, optlen;
2134         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2135         struct inpcb *in6p = sotoinpcb(so);
2136         int level, op, optname;
2137
2138         level = sopt->sopt_level;
2139         op = sopt->sopt_dir;
2140         optname = sopt->sopt_name;
2141         optlen = sopt->sopt_valsize;
2142
2143         if (level != IPPROTO_IPV6) {
2144                 return (EINVAL);
2145         }
2146
2147         switch (optname) {
2148         case IPV6_CHECKSUM:
2149                 /*
2150                  * For ICMPv6 sockets, no modification allowed for checksum
2151                  * offset, permit "no change" values to help existing apps.
2152                  *
2153                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2154                  * for an ICMPv6 socket will fail."
2155                  * The current behavior does not meet RFC3542.
2156                  */
2157                 switch (op) {
2158                 case SOPT_SET:
2159                         if (optlen != sizeof(int)) {
2160                                 error = EINVAL;
2161                                 break;
2162                         }
2163                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2164                                             sizeof(optval));
2165                         if (error)
2166                                 break;
2167                         if ((optval % 2) != 0) {
2168                                 /* the API assumes even offset values */
2169                                 error = EINVAL;
2170                         } else if (so->so_proto->pr_protocol ==
2171                             IPPROTO_ICMPV6) {
2172                                 if (optval != icmp6off)
2173                                         error = EINVAL;
2174                         } else
2175                                 in6p->in6p_cksum = optval;
2176                         break;
2177
2178                 case SOPT_GET:
2179                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2180                                 optval = icmp6off;
2181                         else
2182                                 optval = in6p->in6p_cksum;
2183
2184                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2185                         break;
2186
2187                 default:
2188                         error = EINVAL;
2189                         break;
2190                 }
2191                 break;
2192
2193         default:
2194                 error = ENOPROTOOPT;
2195                 break;
2196         }
2197
2198         return (error);
2199 }
2200
2201 /*
2202  * Set up IP6 options in pcb for insertion in output packets or
2203  * specifying behavior of outgoing packets.
2204  */
2205 static int
2206 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2207     struct socket *so, struct sockopt *sopt)
2208 {
2209         struct ip6_pktopts *opt = *pktopt;
2210         int error = 0;
2211         struct thread *td = sopt->sopt_td;
2212
2213         /* turn off any old options. */
2214         if (opt) {
2215 #ifdef DIAGNOSTIC
2216                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2217                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2218                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2219                         printf("ip6_pcbopts: all specified options are cleared.\n");
2220 #endif
2221                 ip6_clearpktopts(opt, -1);
2222         } else
2223                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2224         *pktopt = NULL;
2225
2226         if (!m || m->m_len == 0) {
2227                 /*
2228                  * Only turning off any previous options, regardless of
2229                  * whether the opt is just created or given.
2230                  */
2231                 free(opt, M_IP6OPT);
2232                 return (0);
2233         }
2234
2235         /*  set options specified by user. */
2236         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2237             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2238                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2239                 free(opt, M_IP6OPT);
2240                 return (error);
2241         }
2242         *pktopt = opt;
2243         return (0);
2244 }
2245
2246 /*
2247  * initialize ip6_pktopts.  beware that there are non-zero default values in
2248  * the struct.
2249  */
2250 void
2251 ip6_initpktopts(struct ip6_pktopts *opt)
2252 {
2253
2254         bzero(opt, sizeof(*opt));
2255         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2256         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2257         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2258         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2259 }
2260
2261 static int
2262 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2263     struct ucred *cred, int uproto)
2264 {
2265         struct ip6_pktopts *opt;
2266
2267         if (*pktopt == NULL) {
2268                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2269                     M_WAITOK);
2270                 ip6_initpktopts(*pktopt);
2271         }
2272         opt = *pktopt;
2273
2274         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2275 }
2276
2277 static int
2278 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt)
2279 {
2280         void *optdata = NULL;
2281         int optdatalen = 0;
2282         struct ip6_ext *ip6e;
2283         int error = 0;
2284         struct in6_pktinfo null_pktinfo;
2285         int deftclass = 0, on;
2286         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2287         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2288
2289         switch (optname) {
2290         case IPV6_PKTINFO:
2291                 optdata = (void *)&null_pktinfo;
2292                 if (pktopt && pktopt->ip6po_pktinfo) {
2293                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2294                             sizeof(null_pktinfo));
2295                         in6_clearscope(&null_pktinfo.ipi6_addr);
2296                 } else {
2297                         /* XXX: we don't have to do this every time... */
2298                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2299                 }
2300                 optdatalen = sizeof(struct in6_pktinfo);
2301                 break;
2302         case IPV6_TCLASS:
2303                 if (pktopt && pktopt->ip6po_tclass >= 0)
2304                         optdata = (void *)&pktopt->ip6po_tclass;
2305                 else
2306                         optdata = (void *)&deftclass;
2307                 optdatalen = sizeof(int);
2308                 break;
2309         case IPV6_HOPOPTS:
2310                 if (pktopt && pktopt->ip6po_hbh) {
2311                         optdata = (void *)pktopt->ip6po_hbh;
2312                         ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
2313                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2314                 }
2315                 break;
2316         case IPV6_RTHDR:
2317                 if (pktopt && pktopt->ip6po_rthdr) {
2318                         optdata = (void *)pktopt->ip6po_rthdr;
2319                         ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
2320                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2321                 }
2322                 break;
2323         case IPV6_RTHDRDSTOPTS:
2324                 if (pktopt && pktopt->ip6po_dest1) {
2325                         optdata = (void *)pktopt->ip6po_dest1;
2326                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
2327                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2328                 }
2329                 break;
2330         case IPV6_DSTOPTS:
2331                 if (pktopt && pktopt->ip6po_dest2) {
2332                         optdata = (void *)pktopt->ip6po_dest2;
2333                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
2334                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2335                 }
2336                 break;
2337         case IPV6_NEXTHOP:
2338                 if (pktopt && pktopt->ip6po_nexthop) {
2339                         optdata = (void *)pktopt->ip6po_nexthop;
2340                         optdatalen = pktopt->ip6po_nexthop->sa_len;
2341                 }
2342                 break;
2343         case IPV6_USE_MIN_MTU:
2344                 if (pktopt)
2345                         optdata = (void *)&pktopt->ip6po_minmtu;
2346                 else
2347                         optdata = (void *)&defminmtu;
2348                 optdatalen = sizeof(int);
2349                 break;
2350         case IPV6_DONTFRAG:
2351                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2352                         on = 1;
2353                 else
2354                         on = 0;
2355                 optdata = (void *)&on;
2356                 optdatalen = sizeof(on);
2357                 break;
2358         case IPV6_PREFER_TEMPADDR:
2359                 if (pktopt)
2360                         optdata = (void *)&pktopt->ip6po_prefer_tempaddr;
2361                 else
2362                         optdata = (void *)&defpreftemp;
2363                 optdatalen = sizeof(int);
2364                 break;
2365         default:                /* should not happen */
2366 #ifdef DIAGNOSTIC
2367                 panic("ip6_getpcbopt: unexpected option\n");
2368 #endif
2369                 return (ENOPROTOOPT);
2370         }
2371
2372         error = sooptcopyout(sopt, optdata, optdatalen);
2373
2374         return (error);
2375 }
2376
2377 void
2378 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2379 {
2380         if (pktopt == NULL)
2381                 return;
2382
2383         if (optname == -1 || optname == IPV6_PKTINFO) {
2384                 if (pktopt->ip6po_pktinfo)
2385                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2386                 pktopt->ip6po_pktinfo = NULL;
2387         }
2388         if (optname == -1 || optname == IPV6_HOPLIMIT)
2389                 pktopt->ip6po_hlim = -1;
2390         if (optname == -1 || optname == IPV6_TCLASS)
2391                 pktopt->ip6po_tclass = -1;
2392         if (optname == -1 || optname == IPV6_NEXTHOP) {
2393                 if (pktopt->ip6po_nextroute.ro_rt) {
2394                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2395                         pktopt->ip6po_nextroute.ro_rt = NULL;
2396                 }
2397                 if (pktopt->ip6po_nexthop)
2398                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2399                 pktopt->ip6po_nexthop = NULL;
2400         }
2401         if (optname == -1 || optname == IPV6_HOPOPTS) {
2402                 if (pktopt->ip6po_hbh)
2403                         free(pktopt->ip6po_hbh, M_IP6OPT);
2404                 pktopt->ip6po_hbh = NULL;
2405         }
2406         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2407                 if (pktopt->ip6po_dest1)
2408                         free(pktopt->ip6po_dest1, M_IP6OPT);
2409                 pktopt->ip6po_dest1 = NULL;
2410         }
2411         if (optname == -1 || optname == IPV6_RTHDR) {
2412                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2413                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2414                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2415                 if (pktopt->ip6po_route.ro_rt) {
2416                         RTFREE(pktopt->ip6po_route.ro_rt);
2417                         pktopt->ip6po_route.ro_rt = NULL;
2418                 }
2419         }
2420         if (optname == -1 || optname == IPV6_DSTOPTS) {
2421                 if (pktopt->ip6po_dest2)
2422                         free(pktopt->ip6po_dest2, M_IP6OPT);
2423                 pktopt->ip6po_dest2 = NULL;
2424         }
2425 }
2426
2427 #define PKTOPT_EXTHDRCPY(type) \
2428 do {\
2429         if (src->type) {\
2430                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2431                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2432                 if (dst->type == NULL && canwait == M_NOWAIT)\
2433                         goto bad;\
2434                 bcopy(src->type, dst->type, hlen);\
2435         }\
2436 } while (/*CONSTCOND*/ 0)
2437
2438 static int
2439 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2440 {
2441         if (dst == NULL || src == NULL)  {
2442                 printf("ip6_clearpktopts: invalid argument\n");
2443                 return (EINVAL);
2444         }
2445
2446         dst->ip6po_hlim = src->ip6po_hlim;
2447         dst->ip6po_tclass = src->ip6po_tclass;
2448         dst->ip6po_flags = src->ip6po_flags;
2449         dst->ip6po_minmtu = src->ip6po_minmtu;
2450         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2451         if (src->ip6po_pktinfo) {
2452                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2453                     M_IP6OPT, canwait);
2454                 if (dst->ip6po_pktinfo == NULL)
2455                         goto bad;
2456                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2457         }
2458         if (src->ip6po_nexthop) {
2459                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2460                     M_IP6OPT, canwait);
2461                 if (dst->ip6po_nexthop == NULL)
2462                         goto bad;
2463                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2464                     src->ip6po_nexthop->sa_len);
2465         }
2466         PKTOPT_EXTHDRCPY(ip6po_hbh);
2467         PKTOPT_EXTHDRCPY(ip6po_dest1);
2468         PKTOPT_EXTHDRCPY(ip6po_dest2);
2469         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2470         return (0);
2471
2472   bad:
2473         ip6_clearpktopts(dst, -1);
2474         return (ENOBUFS);
2475 }
2476 #undef PKTOPT_EXTHDRCPY
2477
2478 struct ip6_pktopts *
2479 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2480 {
2481         int error;
2482         struct ip6_pktopts *dst;
2483
2484         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2485         if (dst == NULL)
2486                 return (NULL);
2487         ip6_initpktopts(dst);
2488
2489         if ((error = copypktopts(dst, src, canwait)) != 0) {
2490                 free(dst, M_IP6OPT);
2491                 return (NULL);
2492         }
2493
2494         return (dst);
2495 }
2496
2497 void
2498 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2499 {
2500         if (pktopt == NULL)
2501                 return;
2502
2503         ip6_clearpktopts(pktopt, -1);
2504
2505         free(pktopt, M_IP6OPT);
2506 }
2507
2508 /*
2509  * Set IPv6 outgoing packet options based on advanced API.
2510  */
2511 int
2512 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2513     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2514 {
2515         struct cmsghdr *cm = NULL;
2516
2517         if (control == NULL || opt == NULL)
2518                 return (EINVAL);
2519
2520         ip6_initpktopts(opt);
2521         if (stickyopt) {
2522                 int error;
2523
2524                 /*
2525                  * If stickyopt is provided, make a local copy of the options
2526                  * for this particular packet, then override them by ancillary
2527                  * objects.
2528                  * XXX: copypktopts() does not copy the cached route to a next
2529                  * hop (if any).  This is not very good in terms of efficiency,
2530                  * but we can allow this since this option should be rarely
2531                  * used.
2532                  */
2533                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2534                         return (error);
2535         }
2536
2537         /*
2538          * XXX: Currently, we assume all the optional information is stored
2539          * in a single mbuf.
2540          */
2541         if (control->m_next)
2542                 return (EINVAL);
2543
2544         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2545             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2546                 int error;
2547
2548                 if (control->m_len < CMSG_LEN(0))
2549                         return (EINVAL);
2550
2551                 cm = mtod(control, struct cmsghdr *);
2552                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2553                         return (EINVAL);
2554                 if (cm->cmsg_level != IPPROTO_IPV6)
2555                         continue;
2556
2557                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2558                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2559                 if (error)
2560                         return (error);
2561         }
2562
2563         return (0);
2564 }
2565
2566 /*
2567  * Set a particular packet option, as a sticky option or an ancillary data
2568  * item.  "len" can be 0 only when it's a sticky option.
2569  * We have 4 cases of combination of "sticky" and "cmsg":
2570  * "sticky=0, cmsg=0": impossible
2571  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2572  * "sticky=1, cmsg=0": RFC3542 socket option
2573  * "sticky=1, cmsg=1": RFC2292 socket option
2574  */
2575 static int
2576 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2577     struct ucred *cred, int sticky, int cmsg, int uproto)
2578 {
2579         int minmtupolicy, preftemp;
2580         int error;
2581
2582         if (!sticky && !cmsg) {
2583 #ifdef DIAGNOSTIC
2584                 printf("ip6_setpktopt: impossible case\n");
2585 #endif
2586                 return (EINVAL);
2587         }
2588
2589         /*
2590          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2591          * not be specified in the context of RFC3542.  Conversely,
2592          * RFC3542 types should not be specified in the context of RFC2292.
2593          */
2594         if (!cmsg) {
2595                 switch (optname) {
2596                 case IPV6_2292PKTINFO:
2597                 case IPV6_2292HOPLIMIT:
2598                 case IPV6_2292NEXTHOP:
2599                 case IPV6_2292HOPOPTS:
2600                 case IPV6_2292DSTOPTS:
2601                 case IPV6_2292RTHDR:
2602                 case IPV6_2292PKTOPTIONS:
2603                         return (ENOPROTOOPT);
2604                 }
2605         }
2606         if (sticky && cmsg) {
2607                 switch (optname) {
2608                 case IPV6_PKTINFO:
2609                 case IPV6_HOPLIMIT:
2610                 case IPV6_NEXTHOP:
2611                 case IPV6_HOPOPTS:
2612                 case IPV6_DSTOPTS:
2613                 case IPV6_RTHDRDSTOPTS:
2614                 case IPV6_RTHDR:
2615                 case IPV6_USE_MIN_MTU:
2616                 case IPV6_DONTFRAG:
2617                 case IPV6_TCLASS:
2618                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2619                         return (ENOPROTOOPT);
2620                 }
2621         }
2622
2623         switch (optname) {
2624         case IPV6_2292PKTINFO:
2625         case IPV6_PKTINFO:
2626         {
2627                 struct ifnet *ifp = NULL;
2628                 struct in6_pktinfo *pktinfo;
2629
2630                 if (len != sizeof(struct in6_pktinfo))
2631                         return (EINVAL);
2632
2633                 pktinfo = (struct in6_pktinfo *)buf;
2634
2635                 /*
2636                  * An application can clear any sticky IPV6_PKTINFO option by
2637                  * doing a "regular" setsockopt with ipi6_addr being
2638                  * in6addr_any and ipi6_ifindex being zero.
2639                  * [RFC 3542, Section 6]
2640                  */
2641                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2642                     pktinfo->ipi6_ifindex == 0 &&
2643                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2644                         ip6_clearpktopts(opt, optname);
2645                         break;
2646                 }
2647
2648                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2649                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2650                         return (EINVAL);
2651                 }
2652                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2653                         return (EINVAL);
2654                 /* validate the interface index if specified. */
2655                 if (pktinfo->ipi6_ifindex > V_if_index)
2656                          return (ENXIO);
2657                 if (pktinfo->ipi6_ifindex) {
2658                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2659                         if (ifp == NULL)
2660                                 return (ENXIO);
2661                 }
2662                 if (ifp != NULL && (
2663                     ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED))
2664                         return (ENETDOWN);
2665
2666                 if (ifp != NULL &&
2667                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2668                         struct in6_ifaddr *ia;
2669
2670                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2671                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2672                         if (ia == NULL)
2673                                 return (EADDRNOTAVAIL);
2674                         ifa_free(&ia->ia_ifa);
2675                 }
2676                 /*
2677                  * We store the address anyway, and let in6_selectsrc()
2678                  * validate the specified address.  This is because ipi6_addr
2679                  * may not have enough information about its scope zone, and
2680                  * we may need additional information (such as outgoing
2681                  * interface or the scope zone of a destination address) to
2682                  * disambiguate the scope.
2683                  * XXX: the delay of the validation may confuse the
2684                  * application when it is used as a sticky option.
2685                  */
2686                 if (opt->ip6po_pktinfo == NULL) {
2687                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2688                             M_IP6OPT, M_NOWAIT);
2689                         if (opt->ip6po_pktinfo == NULL)
2690                                 return (ENOBUFS);
2691                 }
2692                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2693                 break;
2694         }
2695
2696         case IPV6_2292HOPLIMIT:
2697         case IPV6_HOPLIMIT:
2698         {
2699                 int *hlimp;
2700
2701                 /*
2702                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2703                  * to simplify the ordering among hoplimit options.
2704                  */
2705                 if (optname == IPV6_HOPLIMIT && sticky)
2706                         return (ENOPROTOOPT);
2707
2708                 if (len != sizeof(int))
2709                         return (EINVAL);
2710                 hlimp = (int *)buf;
2711                 if (*hlimp < -1 || *hlimp > 255)
2712                         return (EINVAL);
2713
2714                 opt->ip6po_hlim = *hlimp;
2715                 break;
2716         }
2717
2718         case IPV6_TCLASS:
2719         {
2720                 int tclass;
2721
2722                 if (len != sizeof(int))
2723                         return (EINVAL);
2724                 tclass = *(int *)buf;
2725                 if (tclass < -1 || tclass > 255)
2726                         return (EINVAL);
2727
2728                 opt->ip6po_tclass = tclass;
2729                 break;
2730         }
2731
2732         case IPV6_2292NEXTHOP:
2733         case IPV6_NEXTHOP:
2734                 if (cred != NULL) {
2735                         error = priv_check_cred(cred,
2736                             PRIV_NETINET_SETHDROPTS, 0);
2737                         if (error)
2738                                 return (error);
2739                 }
2740
2741                 if (len == 0) { /* just remove the option */
2742                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
2743                         break;
2744                 }
2745
2746                 /* check if cmsg_len is large enough for sa_len */
2747                 if (len < sizeof(struct sockaddr) || len < *buf)
2748                         return (EINVAL);
2749
2750                 switch (((struct sockaddr *)buf)->sa_family) {
2751                 case AF_INET6:
2752                 {
2753                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2754                         int error;
2755
2756                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2757                                 return (EINVAL);
2758
2759                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2760                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2761                                 return (EINVAL);
2762                         }
2763                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2764                             != 0) {
2765                                 return (error);
2766                         }
2767                         break;
2768                 }
2769                 case AF_LINK:   /* should eventually be supported */
2770                 default:
2771                         return (EAFNOSUPPORT);
2772                 }
2773
2774                 /* turn off the previous option, then set the new option. */
2775                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2776                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2777                 if (opt->ip6po_nexthop == NULL)
2778                         return (ENOBUFS);
2779                 bcopy(buf, opt->ip6po_nexthop, *buf);
2780                 break;
2781
2782         case IPV6_2292HOPOPTS:
2783         case IPV6_HOPOPTS:
2784         {
2785                 struct ip6_hbh *hbh;
2786                 int hbhlen;
2787
2788                 /*
2789                  * XXX: We don't allow a non-privileged user to set ANY HbH
2790                  * options, since per-option restriction has too much
2791                  * overhead.
2792                  */
2793                 if (cred != NULL) {
2794                         error = priv_check_cred(cred,
2795                             PRIV_NETINET_SETHDROPTS, 0);
2796                         if (error)
2797                                 return (error);
2798                 }
2799
2800                 if (len == 0) {
2801                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
2802                         break;  /* just remove the option */
2803                 }
2804
2805                 /* message length validation */
2806                 if (len < sizeof(struct ip6_hbh))
2807                         return (EINVAL);
2808                 hbh = (struct ip6_hbh *)buf;
2809                 hbhlen = (hbh->ip6h_len + 1) << 3;
2810                 if (len != hbhlen)
2811                         return (EINVAL);
2812
2813                 /* turn off the previous option, then set the new option. */
2814                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2815                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2816                 if (opt->ip6po_hbh == NULL)
2817                         return (ENOBUFS);
2818                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2819
2820                 break;
2821         }
2822
2823         case IPV6_2292DSTOPTS:
2824         case IPV6_DSTOPTS:
2825         case IPV6_RTHDRDSTOPTS:
2826         {
2827                 struct ip6_dest *dest, **newdest = NULL;
2828                 int destlen;
2829
2830                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
2831                         error = priv_check_cred(cred,
2832                             PRIV_NETINET_SETHDROPTS, 0);
2833                         if (error)
2834                                 return (error);
2835                 }
2836
2837                 if (len == 0) {
2838                         ip6_clearpktopts(opt, optname);
2839                         break;  /* just remove the option */
2840                 }
2841
2842                 /* message length validation */
2843                 if (len < sizeof(struct ip6_dest))
2844                         return (EINVAL);
2845                 dest = (struct ip6_dest *)buf;
2846                 destlen = (dest->ip6d_len + 1) << 3;
2847                 if (len != destlen)
2848                         return (EINVAL);
2849
2850                 /*
2851                  * Determine the position that the destination options header
2852                  * should be inserted; before or after the routing header.
2853                  */
2854                 switch (optname) {
2855                 case IPV6_2292DSTOPTS:
2856                         /*
2857                          * The old advacned API is ambiguous on this point.
2858                          * Our approach is to determine the position based
2859                          * according to the existence of a routing header.
2860                          * Note, however, that this depends on the order of the
2861                          * extension headers in the ancillary data; the 1st
2862                          * part of the destination options header must appear
2863                          * before the routing header in the ancillary data,
2864                          * too.
2865                          * RFC3542 solved the ambiguity by introducing
2866                          * separate ancillary data or option types.
2867                          */
2868                         if (opt->ip6po_rthdr == NULL)
2869                                 newdest = &opt->ip6po_dest1;
2870                         else
2871                                 newdest = &opt->ip6po_dest2;
2872                         break;
2873                 case IPV6_RTHDRDSTOPTS:
2874                         newdest = &opt->ip6po_dest1;
2875                         break;
2876                 case IPV6_DSTOPTS:
2877                         newdest = &opt->ip6po_dest2;
2878                         break;
2879                 }
2880
2881                 /* turn off the previous option, then set the new option. */
2882                 ip6_clearpktopts(opt, optname);
2883                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
2884                 if (*newdest == NULL)
2885                         return (ENOBUFS);
2886                 bcopy(dest, *newdest, destlen);
2887
2888                 break;
2889         }
2890
2891         case IPV6_2292RTHDR:
2892         case IPV6_RTHDR:
2893         {
2894                 struct ip6_rthdr *rth;
2895                 int rthlen;
2896
2897                 if (len == 0) {
2898                         ip6_clearpktopts(opt, IPV6_RTHDR);
2899                         break;  /* just remove the option */
2900                 }
2901
2902                 /* message length validation */
2903                 if (len < sizeof(struct ip6_rthdr))
2904                         return (EINVAL);
2905                 rth = (struct ip6_rthdr *)buf;
2906                 rthlen = (rth->ip6r_len + 1) << 3;
2907                 if (len != rthlen)
2908                         return (EINVAL);
2909
2910                 switch (rth->ip6r_type) {
2911                 case IPV6_RTHDR_TYPE_0:
2912                         if (rth->ip6r_len == 0) /* must contain one addr */
2913                                 return (EINVAL);
2914                         if (rth->ip6r_len % 2) /* length must be even */
2915                                 return (EINVAL);
2916                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2917                                 return (EINVAL);
2918                         break;
2919                 default:
2920                         return (EINVAL);        /* not supported */
2921                 }
2922
2923                 /* turn off the previous option */
2924                 ip6_clearpktopts(opt, IPV6_RTHDR);
2925                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
2926                 if (opt->ip6po_rthdr == NULL)
2927                         return (ENOBUFS);
2928                 bcopy(rth, opt->ip6po_rthdr, rthlen);
2929
2930                 break;
2931         }
2932
2933         case IPV6_USE_MIN_MTU:
2934                 if (len != sizeof(int))
2935                         return (EINVAL);
2936                 minmtupolicy = *(int *)buf;
2937                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
2938                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
2939                     minmtupolicy != IP6PO_MINMTU_ALL) {
2940                         return (EINVAL);
2941                 }
2942                 opt->ip6po_minmtu = minmtupolicy;
2943                 break;
2944
2945         case IPV6_DONTFRAG:
2946                 if (len != sizeof(int))
2947                         return (EINVAL);
2948
2949                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
2950                         /*
2951                          * we ignore this option for TCP sockets.
2952                          * (RFC3542 leaves this case unspecified.)
2953                          */
2954                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
2955                 } else
2956                         opt->ip6po_flags |= IP6PO_DONTFRAG;
2957                 break;
2958
2959         case IPV6_PREFER_TEMPADDR:
2960                 if (len != sizeof(int))
2961                         return (EINVAL);
2962                 preftemp = *(int *)buf;
2963                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
2964                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
2965                     preftemp != IP6PO_TEMPADDR_PREFER) {
2966                         return (EINVAL);
2967                 }
2968                 opt->ip6po_prefer_tempaddr = preftemp;
2969                 break;
2970
2971         default:
2972                 return (ENOPROTOOPT);
2973         } /* end of switch */
2974
2975         return (0);
2976 }
2977
2978 /*
2979  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2980  * packet to the input queue of a specified interface.  Note that this
2981  * calls the output routine of the loopback "driver", but with an interface
2982  * pointer that might NOT be &loif -- easier than replicating that code here.
2983  */
2984 void
2985 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
2986 {
2987         struct mbuf *copym;
2988         struct ip6_hdr *ip6;
2989
2990         copym = m_copy(m, 0, M_COPYALL);
2991         if (copym == NULL)
2992                 return;
2993
2994         /*
2995          * Make sure to deep-copy IPv6 header portion in case the data
2996          * is in an mbuf cluster, so that we can safely override the IPv6
2997          * header portion later.
2998          */
2999         if (!M_WRITABLE(copym) ||
3000             copym->m_len < sizeof(struct ip6_hdr)) {
3001                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3002                 if (copym == NULL)
3003                         return;
3004         }
3005         ip6 = mtod(copym, struct ip6_hdr *);
3006         /*
3007          * clear embedded scope identifiers if necessary.
3008          * in6_clearscope will touch the addresses only when necessary.
3009          */
3010         in6_clearscope(&ip6->ip6_src);
3011         in6_clearscope(&ip6->ip6_dst);
3012         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3013                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3014                     CSUM_PSEUDO_HDR;
3015                 copym->m_pkthdr.csum_data = 0xffff;
3016         }
3017         if_simloop(ifp, copym, AF_INET6, 0);
3018 }
3019
3020 /*
3021  * Chop IPv6 header off from the payload.
3022  */
3023 static int
3024 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3025 {
3026         struct mbuf *mh;
3027         struct ip6_hdr *ip6;
3028
3029         ip6 = mtod(m, struct ip6_hdr *);
3030         if (m->m_len > sizeof(*ip6)) {
3031                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3032                 if (mh == NULL) {
3033                         m_freem(m);
3034                         return ENOBUFS;
3035                 }
3036                 m_move_pkthdr(mh, m);
3037                 M_ALIGN(mh, sizeof(*ip6));
3038                 m->m_len -= sizeof(*ip6);
3039                 m->m_data += sizeof(*ip6);
3040                 mh->m_next = m;
3041                 m = mh;
3042                 m->m_len = sizeof(*ip6);
3043                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3044         }
3045         exthdrs->ip6e_ip6 = m;
3046         return 0;
3047 }
3048
3049 /*
3050  * Compute IPv6 extension header length.
3051  */
3052 int
3053 ip6_optlen(struct inpcb *in6p)
3054 {
3055         int len;
3056
3057         if (!in6p->in6p_outputopts)
3058                 return 0;
3059
3060         len = 0;
3061 #define elen(x) \
3062     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3063
3064         len += elen(in6p->in6p_outputopts->ip6po_hbh);
3065         if (in6p->in6p_outputopts->ip6po_rthdr)
3066                 /* dest1 is valid with rthdr only */
3067                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
3068         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
3069         len += elen(in6p->in6p_outputopts->ip6po_dest2);
3070         return len;
3071 #undef elen
3072 }