sys/netinet6/ip6_output.c

   1 /*-
   2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $
  30  */
  31
  32 /*-
  33  * Copyright (c) 1982, 1986, 1988, 1990, 1993
  34  *      The Regents of the University of California.  All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  * 1. Redistributions of source code must retain the above copyright
  40  *    notice, this list of conditions and the following disclaimer.
  41  * 2. Redistributions in binary form must reproduce the above copyright
  42  *    notice, this list of conditions and the following disclaimer in the
  43  *    documentation and/or other materials provided with the distribution.
  44  * 4. Neither the name of the University nor the names of its contributors
  45  *    may be used to endorse or promote products derived from this software
  46  *    without specific prior written permission.
  47  *
  48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  58  * SUCH DAMAGE.
  59  *
  60  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  61  */
  62
  63 #include <sys/cdefs.h>
  64 __FBSDID("$FreeBSD$");
  65
  66 #include "opt_inet.h"
  67 #include "opt_inet6.h"
  68 #include "opt_ipfw.h"
  69 #include "opt_ipsec.h"
  70 #include "opt_sctp.h"
  71 #include "opt_route.h"
  72 #include "opt_rss.h"
  73
  74 #include <sys/param.h>
  75 #include <sys/kernel.h>
  76 #include <sys/malloc.h>
  77 #include <sys/mbuf.h>
  78 #include <sys/errno.h>
  79 #include <sys/priv.h>
  80 #include <sys/proc.h>
  81 #include <sys/protosw.h>
  82 #include <sys/socket.h>
  83 #include <sys/socketvar.h>
  84 #include <sys/syslog.h>
  85 #include <sys/ucred.h>
  86
  87 #include <machine/in_cksum.h>
  88
  89 #include <net/if.h>
  90 #include <net/if_var.h>
  91 #include <net/netisr.h>
  92 #include <net/route.h>
  93 #include <net/pfil.h>
  94 #include <net/rss_config.h>
  95 #include <net/vnet.h>
  96
  97 #include <netinet/in.h>
  98 #include <netinet/in_var.h>
  99 #include <netinet/ip_var.h>
 100 #include <netinet6/in6_fib.h>
 101 #include <netinet6/in6_var.h>
 102 #include <netinet/ip6.h>
 103 #include <netinet/icmp6.h>
 104 #include <netinet6/ip6_var.h>
 105 #include <netinet/in_pcb.h>
 106 #include <netinet/tcp_var.h>
 107 #include <netinet6/nd6.h>
 108 #include <netinet6/in6_rss.h>
 109
 110 #ifdef IPSEC
 111 #include <netipsec/ipsec.h>
 112 #include <netipsec/ipsec6.h>
 113 #include <netipsec/key.h>
 114 #include <netinet6/ip6_ipsec.h>
 115 #endif /* IPSEC */
 116 #ifdef SCTP
 117 #include <netinet/sctp.h>
 118 #include <netinet/sctp_crc32.h>
 119 #endif
 120
 121 #include <netinet6/ip6protosw.h>
 122 #include <netinet6/scope6_var.h>
 123
 124 #ifdef FLOWTABLE
 125 #include <net/flowtable.h>
 126 #endif
 127
 128 extern int in6_mcast_loop;
 129
 130 struct ip6_exthdrs {
 131         struct mbuf *ip6e_ip6;
 132         struct mbuf *ip6e_hbh;
 133         struct mbuf *ip6e_dest1;
 134         struct mbuf *ip6e_rthdr;
 135         struct mbuf *ip6e_dest2;
 136 };
 137
 138 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 139
 140 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 141                            struct ucred *, int);
 142 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 143         struct socket *, struct sockopt *);
 144 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *);
 145 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 146         struct ucred *, int, int, int);
 147
 148 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 149 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 150         struct ip6_frag **);
 151 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 152 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 153 static int ip6_getpmtu(struct route_in6 *, int,
 154         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int);
 155 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 156         u_long *, int *);
 157 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 158 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 159
 160
 161 /*
 162  * Make an extension header from option data.  hp is the source, and
 163  * mp is the destination.
 164  */
 165 #define MAKE_EXTHDR(hp, mp)                                             \
 166     do {                                                                \
 167         if (hp) {                                                       \
 168                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 169                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 170                     ((eh)->ip6e_len + 1) << 3);                         \
 171                 if (error)                                              \
 172                         goto freehdrs;                                  \
 173         }                                                               \
 174     } while (/*CONSTCOND*/ 0)
 175
 176 /*
 177  * Form a chain of extension headers.
 178  * m is the extension header mbuf
 179  * mp is the previous mbuf in the chain
 180  * p is the next header
 181  * i is the type of option.
 182  */
 183 #define MAKE_CHAIN(m, mp, p, i)\
 184     do {\
 185         if (m) {\
 186                 if (!hdrsplit) \
 187                         panic("assumption failed: hdr not split"); \
 188                 *mtod((m), u_char *) = *(p);\
 189                 *(p) = (i);\
 190                 p = mtod((m), u_char *);\
 191                 (m)->m_next = (mp)->m_next;\
 192                 (mp)->m_next = (m);\
 193                 (mp) = (m);\
 194         }\
 195     } while (/*CONSTCOND*/ 0)
 196
 197 void
 198 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 199 {
 200         u_short csum;
 201
 202         csum = in_cksum_skip(m, offset + plen, offset);
 203         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 204                 csum = 0xffff;
 205         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 206
 207         if (offset + sizeof(u_short) > m->m_len) {
 208                 printf("%s: delayed m_pullup, m->len: %d plen %u off %u "
 209                     "csum_flags=%b\n", __func__, m->m_len, plen, offset,
 210                     (int)m->m_pkthdr.csum_flags, CSUM_BITS);
 211                 /*
 212                  * XXX this should not happen, but if it does, the correct
 213                  * behavior may be to insert the checksum in the appropriate
 214                  * next mbuf in the chain.
 215                  */
 216                 return;
 217         }
 218         *(u_short *)(m->m_data + offset) = csum;
 219 }
 220
 221 int
 222 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 223     int mtu, uint32_t id)
 224 {
 225         struct mbuf *m, **mnext, *m_frgpart;
 226         struct ip6_hdr *ip6, *mhip6;
 227         struct ip6_frag *ip6f;
 228         int off;
 229         int error;
 230         int tlen = m0->m_pkthdr.len;
 231
 232         m = m0;
 233         ip6 = mtod(m, struct ip6_hdr *);
 234         mnext = &m->m_nextpkt;
 235
 236         for (off = hlen; off < tlen; off += mtu) {
 237                 m = m_gethdr(M_NOWAIT, MT_DATA);
 238                 if (!m) {
 239                         IP6STAT_INC(ip6s_odropped);
 240                         return (ENOBUFS);
 241                 }
 242                 m->m_flags = m0->m_flags & M_COPYFLAGS;
 243                 *mnext = m;
 244                 mnext = &m->m_nextpkt;
 245                 m->m_data += max_linkhdr;
 246                 mhip6 = mtod(m, struct ip6_hdr *);
 247                 *mhip6 = *ip6;
 248                 m->m_len = sizeof(*mhip6);
 249                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 250                 if (error) {
 251                         IP6STAT_INC(ip6s_odropped);
 252                         return (error);
 253                 }
 254                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 255                 if (off + mtu >= tlen)
 256                         mtu = tlen - off;
 257                 else
 258                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 259                 mhip6->ip6_plen = htons((u_short)(mtu + hlen +
 260                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 261                 if ((m_frgpart = m_copy(m0, off, mtu)) == NULL) {
 262                         IP6STAT_INC(ip6s_odropped);
 263                         return (ENOBUFS);
 264                 }
 265                 m_cat(m, m_frgpart);
 266                 m->m_pkthdr.len = mtu + hlen + sizeof(*ip6f);
 267                 m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum;
 268                 m->m_pkthdr.rcvif = NULL;
 269                 ip6f->ip6f_reserved = 0;
 270                 ip6f->ip6f_ident = id;
 271                 ip6f->ip6f_nxt = nextproto;
 272                 IP6STAT_INC(ip6s_ofragments);
 273                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 274         }
 275
 276         return (0);
 277 }
 278
 279 /*
 280  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 281  * header (with pri, len, nxt, hlim, src, dst).
 282  * This function may modify ver and hlim only.
 283  * The mbuf chain containing the packet will be freed.
 284  * The mbuf opt, if present, will not be freed.
 285  * If route_in6 ro is present and has ro_rt initialized, route lookup would be
 286  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 287  * then result of route lookup is stored in ro->ro_rt.
 288  *
 289  * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
 290  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 291  * which is rt_mtu.
 292  *
 293  * ifpp - XXX: just for statistics
 294  */
 295 /*
 296  * XXX TODO: no flowid is assigned for outbound flows?
 297  */
 298 int
 299 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 300     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 301     struct ifnet **ifpp, struct inpcb *inp)
 302 {
 303         struct ip6_hdr *ip6;
 304         struct ifnet *ifp, *origifp;
 305         struct mbuf *m = m0;
 306         struct mbuf *mprev = NULL;
 307         int hlen, tlen, len;
 308         struct route_in6 ip6route;
 309         struct rtentry *rt = NULL;
 310         struct sockaddr_in6 *dst, src_sa, dst_sa;
 311         struct in6_addr odst;
 312         int error = 0;
 313         struct in6_ifaddr *ia = NULL;
 314         u_long mtu;
 315         int alwaysfrag, dontfrag;
 316         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 317         struct ip6_exthdrs exthdrs;
 318         struct in6_addr src0, dst0;
 319         u_int32_t zone;
 320         struct route_in6 *ro_pmtu = NULL;
 321         int hdrsplit = 0;
 322         int sw_csum, tso;
 323         int needfiblookup;
 324         uint32_t fibnum;
 325         struct m_tag *fwd_tag = NULL;
 326         uint32_t id;
 327
 328         if (inp != NULL) {
 329                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 330                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 331                         /* unconditionally set flowid */
 332                         m->m_pkthdr.flowid = inp->inp_flowid;
 333                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 334                 }
 335         }
 336
 337         bzero(&exthdrs, sizeof(exthdrs));
 338         if (opt) {
 339                 /* Hop-by-Hop options header */
 340                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 341                 /* Destination options header(1st part) */
 342                 if (opt->ip6po_rthdr) {
 343                         /*
 344                          * Destination options header(1st part)
 345                          * This only makes sense with a routing header.
 346                          * See Section 9.2 of RFC 3542.
 347                          * Disabling this part just for MIP6 convenience is
 348                          * a bad idea.  We need to think carefully about a
 349                          * way to make the advanced API coexist with MIP6
 350                          * options, which might automatically be inserted in
 351                          * the kernel.
 352                          */
 353                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 354                 }
 355                 /* Routing header */
 356                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 357                 /* Destination options header(2nd part) */
 358                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 359         }
 360
 361 #ifdef IPSEC
 362         /*
 363          * IPSec checking which handles several cases.
 364          * FAST IPSEC: We re-injected the packet.
 365          * XXX: need scope argument.
 366          */
 367         switch(ip6_ipsec_output(&m, inp, &error))
 368         {
 369         case 1:                 /* Bad packet */
 370                 goto freehdrs;
 371         case -1:                /* IPSec done */
 372                 goto done;
 373         case 0:                 /* No IPSec */
 374         default:
 375                 break;
 376         }
 377 #endif /* IPSEC */
 378
 379         /*
 380          * Calculate the total length of the extension header chain.
 381          * Keep the length of the unfragmentable part for fragmentation.
 382          */
 383         optlen = 0;
 384         if (exthdrs.ip6e_hbh)
 385                 optlen += exthdrs.ip6e_hbh->m_len;
 386         if (exthdrs.ip6e_dest1)
 387                 optlen += exthdrs.ip6e_dest1->m_len;
 388         if (exthdrs.ip6e_rthdr)
 389                 optlen += exthdrs.ip6e_rthdr->m_len;
 390         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 391
 392         /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
 393         if (exthdrs.ip6e_dest2)
 394                 optlen += exthdrs.ip6e_dest2->m_len;
 395
 396         /*
 397          * If there is at least one extension header,
 398          * separate IP6 header from the payload.
 399          */
 400         if (optlen && !hdrsplit) {
 401                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 402                         m = NULL;
 403                         goto freehdrs;
 404                 }
 405                 m = exthdrs.ip6e_ip6;
 406                 hdrsplit++;
 407         }
 408
 409         ip6 = mtod(m, struct ip6_hdr *);
 410
 411         /* adjust mbuf packet header length */
 412         m->m_pkthdr.len += optlen;
 413         plen = m->m_pkthdr.len - sizeof(*ip6);
 414
 415         /* If this is a jumbo payload, insert a jumbo payload option. */
 416         if (plen > IPV6_MAXPACKET) {
 417                 if (!hdrsplit) {
 418                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 419                                 m = NULL;
 420                                 goto freehdrs;
 421                         }
 422                         m = exthdrs.ip6e_ip6;
 423                         hdrsplit++;
 424                 }
 425                 /* adjust pointer */
 426                 ip6 = mtod(m, struct ip6_hdr *);
 427                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 428                         goto freehdrs;
 429                 ip6->ip6_plen = 0;
 430         } else
 431                 ip6->ip6_plen = htons(plen);
 432
 433         /*
 434          * Concatenate headers and fill in next header fields.
 435          * Here we have, on "m"
 436          *      IPv6 payload
 437          * and we insert headers accordingly.  Finally, we should be getting:
 438          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 439          *
 440          * during the header composing process, "m" points to IPv6 header.
 441          * "mprev" points to an extension header prior to esp.
 442          */
 443         u_char *nexthdrp = &ip6->ip6_nxt;
 444         mprev = m;
 445
 446         /*
 447          * we treat dest2 specially.  this makes IPsec processing
 448          * much easier.  the goal here is to make mprev point the
 449          * mbuf prior to dest2.
 450          *
 451          * result: IPv6 dest2 payload
 452          * m and mprev will point to IPv6 header.
 453          */
 454         if (exthdrs.ip6e_dest2) {
 455                 if (!hdrsplit)
 456                         panic("assumption failed: hdr not split");
 457                 exthdrs.ip6e_dest2->m_next = m->m_next;
 458                 m->m_next = exthdrs.ip6e_dest2;
 459                 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 460                 ip6->ip6_nxt = IPPROTO_DSTOPTS;
 461         }
 462
 463         /*
 464          * result: IPv6 hbh dest1 rthdr dest2 payload
 465          * m will point to IPv6 header.  mprev will point to the
 466          * extension header prior to dest2 (rthdr in the above case).
 467          */
 468         MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 469         MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 470                    IPPROTO_DSTOPTS);
 471         MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 472                    IPPROTO_ROUTING);
 473
 474         /*
 475          * If there is a routing header, discard the packet.
 476          */
 477         if (exthdrs.ip6e_rthdr) {
 478                  error = EINVAL;
 479                  goto bad;
 480         }
 481
 482         /* Source address validation */
 483         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 484             (flags & IPV6_UNSPECSRC) == 0) {
 485                 error = EOPNOTSUPP;
 486                 IP6STAT_INC(ip6s_badscope);
 487                 goto bad;
 488         }
 489         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 490                 error = EOPNOTSUPP;
 491                 IP6STAT_INC(ip6s_badscope);
 492                 goto bad;
 493         }
 494
 495         IP6STAT_INC(ip6s_localout);
 496
 497         /*
 498          * Route packet.
 499          */
 500         if (ro == NULL) {
 501                 ro = &ip6route;
 502                 bzero((caddr_t)ro, sizeof(*ro));
 503         } else
 504                 ro->ro_flags |= RT_LLE_CACHE;
 505         ro_pmtu = ro;
 506         if (opt && opt->ip6po_rthdr)
 507                 ro = &opt->ip6po_route;
 508         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 509 #ifdef FLOWTABLE
 510         if (ro->ro_rt == NULL)
 511                 (void )flowtable_lookup(AF_INET6, m, (struct route *)ro);
 512 #endif
 513         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 514 again:
 515         /*
 516          * if specified, try to fill in the traffic class field.
 517          * do not override if a non-zero value is already set.
 518          * we check the diffserv field and the ecn field separately.
 519          */
 520         if (opt && opt->ip6po_tclass >= 0) {
 521                 int mask = 0;
 522
 523                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 524                         mask |= 0xfc;
 525                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 526                         mask |= 0x03;
 527                 if (mask != 0)
 528                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 529         }
 530
 531         /* fill in or override the hop limit field, if necessary. */
 532         if (opt && opt->ip6po_hlim != -1)
 533                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 534         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 535                 if (im6o != NULL)
 536                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 537                 else
 538                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 539         }
 540         /*
 541          * Validate route against routing table additions;
 542          * a better/more specific route might have been added.
 543          * Make sure address family is set in route.
 544          */
 545         if (inp) {
 546                 ro->ro_dst.sin6_family = AF_INET6;
 547                 RT_VALIDATE((struct route *)ro, &inp->inp_rt_cookie, fibnum);
 548         }
 549         if (ro->ro_rt && fwd_tag == NULL && (ro->ro_rt->rt_flags & RTF_UP) &&
 550             ro->ro_dst.sin6_family == AF_INET6 &&
 551             IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 552                 rt = ro->ro_rt;
 553                 ifp = ro->ro_rt->rt_ifp;
 554         } else {
 555                 if (fwd_tag == NULL) {
 556                         bzero(&dst_sa, sizeof(dst_sa));
 557                         dst_sa.sin6_family = AF_INET6;
 558                         dst_sa.sin6_len = sizeof(dst_sa);
 559                         dst_sa.sin6_addr = ip6->ip6_dst;
 560                 }
 561                 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
 562                     &rt, fibnum);
 563                 if (error != 0) {
 564                         if (ifp != NULL)
 565                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 566                         goto bad;
 567                 }
 568         }
 569         if (rt == NULL) {
 570                 /*
 571                  * If in6_selectroute() does not return a route entry,
 572                  * dst may not have been updated.
 573                  */
 574                 *dst = dst_sa;  /* XXX */
 575         }
 576
 577         /*
 578          * then rt (for unicast) and ifp must be non-NULL valid values.
 579          */
 580         if ((flags & IPV6_FORWARDING) == 0) {
 581                 /* XXX: the FORWARDING flag can be set for mrouting. */
 582                 in6_ifstat_inc(ifp, ifs6_out_request);
 583         }
 584         if (rt != NULL) {
 585                 ia = (struct in6_ifaddr *)(rt->rt_ifa);
 586                 counter_u64_add(rt->rt_pksent, 1);
 587         }
 588
 589
 590         /*
 591          * The outgoing interface must be in the zone of source and
 592          * destination addresses.
 593          */
 594         origifp = ifp;
 595
 596         src0 = ip6->ip6_src;
 597         if (in6_setscope(&src0, origifp, &zone))
 598                 goto badscope;
 599         bzero(&src_sa, sizeof(src_sa));
 600         src_sa.sin6_family = AF_INET6;
 601         src_sa.sin6_len = sizeof(src_sa);
 602         src_sa.sin6_addr = ip6->ip6_src;
 603         if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id)
 604                 goto badscope;
 605
 606         dst0 = ip6->ip6_dst;
 607         if (in6_setscope(&dst0, origifp, &zone))
 608                 goto badscope;
 609         /* re-initialize to be sure */
 610         bzero(&dst_sa, sizeof(dst_sa));
 611         dst_sa.sin6_family = AF_INET6;
 612         dst_sa.sin6_len = sizeof(dst_sa);
 613         dst_sa.sin6_addr = ip6->ip6_dst;
 614         if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) {
 615                 goto badscope;
 616         }
 617
 618         /* We should use ia_ifp to support the case of
 619          * sending packets to an address of our own.
 620          */
 621         if (ia != NULL && ia->ia_ifp)
 622                 ifp = ia->ia_ifp;
 623
 624         /* scope check is done. */
 625         goto routefound;
 626
 627   badscope:
 628         IP6STAT_INC(ip6s_badscope);
 629         in6_ifstat_inc(origifp, ifs6_out_discard);
 630         if (error == 0)
 631                 error = EHOSTUNREACH; /* XXX */
 632         goto bad;
 633
 634   routefound:
 635         if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 636                 if (opt && opt->ip6po_nextroute.ro_rt) {
 637                         /*
 638                          * The nexthop is explicitly specified by the
 639                          * application.  We assume the next hop is an IPv6
 640                          * address.
 641                          */
 642                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 643                 }
 644                 else if ((rt->rt_flags & RTF_GATEWAY))
 645                         dst = (struct sockaddr_in6 *)rt->rt_gateway;
 646         }
 647
 648         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 649                 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
 650         } else {
 651                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 652                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 653                 /*
 654                  * Confirm that the outgoing interface supports multicast.
 655                  */
 656                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 657                         IP6STAT_INC(ip6s_noroute);
 658                         in6_ifstat_inc(ifp, ifs6_out_discard);
 659                         error = ENETUNREACH;
 660                         goto bad;
 661                 }
 662                 if ((im6o == NULL && in6_mcast_loop) ||
 663                     (im6o && im6o->im6o_multicast_loop)) {
 664                         /*
 665                          * Loop back multicast datagram if not expressly
 666                          * forbidden to do so, even if we have not joined
 667                          * the address; protocols will filter it later,
 668                          * thus deferring a hash lookup and lock acquisition
 669                          * at the expense of an m_copym().
 670                          */
 671                         ip6_mloopback(ifp, m);
 672                 } else {
 673                         /*
 674                          * If we are acting as a multicast router, perform
 675                          * multicast forwarding as if the packet had just
 676                          * arrived on the interface to which we are about
 677                          * to send.  The multicast forwarding function
 678                          * recursively calls this function, using the
 679                          * IPV6_FORWARDING flag to prevent infinite recursion.
 680                          *
 681                          * Multicasts that are looped back by ip6_mloopback(),
 682                          * above, will be forwarded by the ip6_input() routine,
 683                          * if necessary.
 684                          */
 685                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 686                                 /*
 687                                  * XXX: ip6_mforward expects that rcvif is NULL
 688                                  * when it is called from the originating path.
 689                                  * However, it may not always be the case.
 690                                  */
 691                                 m->m_pkthdr.rcvif = NULL;
 692                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 693                                         m_freem(m);
 694                                         goto done;
 695                                 }
 696                         }
 697                 }
 698                 /*
 699                  * Multicasts with a hoplimit of zero may be looped back,
 700                  * above, but must not be transmitted on a network.
 701                  * Also, multicasts addressed to the loopback interface
 702                  * are not sent -- the above call to ip6_mloopback() will
 703                  * loop back a copy if this host actually belongs to the
 704                  * destination group on the loopback interface.
 705                  */
 706                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 707                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 708                         m_freem(m);
 709                         goto done;
 710                 }
 711         }
 712
 713         /*
 714          * Fill the outgoing inteface to tell the upper layer
 715          * to increment per-interface statistics.
 716          */
 717         if (ifpp)
 718                 *ifpp = ifp;
 719
 720         /* Determine path MTU. */
 721         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 722             &mtu, &alwaysfrag, fibnum)) != 0)
 723                 goto bad;
 724
 725         /*
 726          * The caller of this function may specify to use the minimum MTU
 727          * in some cases.
 728          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 729          * setting.  The logic is a bit complicated; by default, unicast
 730          * packets will follow path MTU while multicast packets will be sent at
 731          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 732          * including unicast ones will be sent at the minimum MTU.  Multicast
 733          * packets will always be sent at the minimum MTU unless
 734          * IP6PO_MINMTU_DISABLE is explicitly specified.
 735          * See RFC 3542 for more details.
 736          */
 737         if (mtu > IPV6_MMTU) {
 738                 if ((flags & IPV6_MINMTU))
 739                         mtu = IPV6_MMTU;
 740                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 741                         mtu = IPV6_MMTU;
 742                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 743                          (opt == NULL ||
 744                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 745                         mtu = IPV6_MMTU;
 746                 }
 747         }
 748
 749         /*
 750          * clear embedded scope identifiers if necessary.
 751          * in6_clearscope will touch the addresses only when necessary.
 752          */
 753         in6_clearscope(&ip6->ip6_src);
 754         in6_clearscope(&ip6->ip6_dst);
 755
 756         /*
 757          * If the outgoing packet contains a hop-by-hop options header,
 758          * it must be examined and processed even by the source node.
 759          * (RFC 2460, section 4.)
 760          */
 761         if (exthdrs.ip6e_hbh) {
 762                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 763                 u_int32_t dummy; /* XXX unused */
 764                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 765
 766 #ifdef DIAGNOSTIC
 767                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 768                         panic("ip6e_hbh is not contiguous");
 769 #endif
 770                 /*
 771                  *  XXX: if we have to send an ICMPv6 error to the sender,
 772                  *       we need the M_LOOP flag since icmp6_error() expects
 773                  *       the IPv6 and the hop-by-hop options header are
 774                  *       contiguous unless the flag is set.
 775                  */
 776                 m->m_flags |= M_LOOP;
 777                 m->m_pkthdr.rcvif = ifp;
 778                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 779                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 780                     &dummy, &plen) < 0) {
 781                         /* m was already freed at this point */
 782                         error = EINVAL;/* better error? */
 783                         goto done;
 784                 }
 785                 m->m_flags &= ~M_LOOP; /* XXX */
 786                 m->m_pkthdr.rcvif = NULL;
 787         }
 788
 789         /* Jump over all PFIL processing if hooks are not active. */
 790         if (!PFIL_HOOKED(&V_inet6_pfil_hook))
 791                 goto passout;
 792
 793         odst = ip6->ip6_dst;
 794         /* Run through list of hooks for output packets. */
 795         error = pfil_run_hooks(&V_inet6_pfil_hook, &m, ifp, PFIL_OUT, inp);
 796         if (error != 0 || m == NULL)
 797                 goto done;
 798         /* adjust pointer */
 799         ip6 = mtod(m, struct ip6_hdr *);
 800
 801         needfiblookup = 0;
 802         /* See if destination IP address was changed by packet filter. */
 803         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
 804                 m->m_flags |= M_SKIP_FIREWALL;
 805                 /* If destination is now ourself drop to ip6_input(). */
 806                 if (in6_localip(&ip6->ip6_dst)) {
 807                         m->m_flags |= M_FASTFWD_OURS;
 808                         if (m->m_pkthdr.rcvif == NULL)
 809                                 m->m_pkthdr.rcvif = V_loif;
 810                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 811                                 m->m_pkthdr.csum_flags |=
 812                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 813                                 m->m_pkthdr.csum_data = 0xffff;
 814                         }
 815 #ifdef SCTP
 816                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 817                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 818 #endif
 819                         error = netisr_queue(NETISR_IPV6, m);
 820                         goto done;
 821                 } else {
 822                         RO_RTFREE(ro);
 823                         needfiblookup = 1; /* Redo the routing table lookup. */
 824                 }
 825         }
 826         /* See if fib was changed by packet filter. */
 827         if (fibnum != M_GETFIB(m)) {
 828                 m->m_flags |= M_SKIP_FIREWALL;
 829                 fibnum = M_GETFIB(m);
 830                 RO_RTFREE(ro);
 831                 needfiblookup = 1;
 832         }
 833         if (needfiblookup)
 834                 goto again;
 835
 836         /* See if local, if yes, send it to netisr. */
 837         if (m->m_flags & M_FASTFWD_OURS) {
 838                 if (m->m_pkthdr.rcvif == NULL)
 839                         m->m_pkthdr.rcvif = V_loif;
 840                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 841                         m->m_pkthdr.csum_flags |=
 842                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 843                         m->m_pkthdr.csum_data = 0xffff;
 844                 }
 845 #ifdef SCTP
 846                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 847                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 848 #endif
 849                 error = netisr_queue(NETISR_IPV6, m);
 850                 goto done;
 851         }
 852         /* Or forward to some other address? */
 853         if ((m->m_flags & M_IP6_NEXTHOP) &&
 854             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 855                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 856                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
 857                 m->m_flags |= M_SKIP_FIREWALL;
 858                 m->m_flags &= ~M_IP6_NEXTHOP;
 859                 m_tag_delete(m, fwd_tag);
 860                 goto again;
 861         }
 862
 863 passout:
 864         /*
 865          * Send the packet to the outgoing interface.
 866          * If necessary, do IPv6 fragmentation before sending.
 867          *
 868          * the logic here is rather complex:
 869          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 870          * 1-a: send as is if tlen <= path mtu
 871          * 1-b: fragment if tlen > path mtu
 872          *
 873          * 2: if user asks us not to fragment (dontfrag == 1)
 874          * 2-a: send as is if tlen <= interface mtu
 875          * 2-b: error if tlen > interface mtu
 876          *
 877          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 878          *      always fragment
 879          *
 880          * 4: if dontfrag == 1 && alwaysfrag == 1
 881          *      error, as we cannot handle this conflicting request
 882          */
 883         sw_csum = m->m_pkthdr.csum_flags;
 884         if (!hdrsplit) {
 885                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
 886                 sw_csum &= ~ifp->if_hwassist;
 887         } else
 888                 tso = 0;
 889         /*
 890          * If we added extension headers, we will not do TSO and calculate the
 891          * checksums ourselves for now.
 892          * XXX-BZ  Need a framework to know when the NIC can handle it, even
 893          * with ext. hdrs.
 894          */
 895         if (sw_csum & CSUM_DELAY_DATA_IPV6) {
 896                 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
 897                 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
 898         }
 899 #ifdef SCTP
 900         if (sw_csum & CSUM_SCTP_IPV6) {
 901                 sw_csum &= ~CSUM_SCTP_IPV6;
 902                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
 903         }
 904 #endif
 905         m->m_pkthdr.csum_flags &= ifp->if_hwassist;
 906         tlen = m->m_pkthdr.len;
 907
 908         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
 909                 dontfrag = 1;
 910         else
 911                 dontfrag = 0;
 912         if (dontfrag && alwaysfrag) {   /* case 4 */
 913                 /* conflicting request - can't transmit */
 914                 error = EMSGSIZE;
 915                 goto bad;
 916         }
 917         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* case 2-b */
 918                 /*
 919                  * Even if the DONTFRAG option is specified, we cannot send the
 920                  * packet when the data length is larger than the MTU of the
 921                  * outgoing interface.
 922                  * Notify the error by sending IPV6_PATHMTU ancillary data if
 923                  * application wanted to know the MTU value. Also return an
 924                  * error code (this is not described in the API spec).
 925                  */
 926                 if (inp != NULL)
 927                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
 928                 error = EMSGSIZE;
 929                 goto bad;
 930         }
 931
 932         /*
 933          * transmit packet without fragmentation
 934          */
 935         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
 936                 struct in6_ifaddr *ia6;
 937
 938                 ip6 = mtod(m, struct ip6_hdr *);
 939                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
 940                 if (ia6) {
 941                         /* Record statistics for this interface address. */
 942                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
 943                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
 944                             m->m_pkthdr.len);
 945                         ifa_free(&ia6->ia_ifa);
 946                 }
 947                 error = nd6_output_ifp(ifp, origifp, m, dst,
 948                     (struct route *)ro);
 949                 goto done;
 950         }
 951
 952         /*
 953          * try to fragment the packet.  case 1-b and 3
 954          */
 955         if (mtu < IPV6_MMTU) {
 956                 /* path MTU cannot be less than IPV6_MMTU */
 957                 error = EMSGSIZE;
 958                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 959                 goto bad;
 960         } else if (ip6->ip6_plen == 0) {
 961                 /* jumbo payload cannot be fragmented */
 962                 error = EMSGSIZE;
 963                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 964                 goto bad;
 965         } else {
 966                 u_char nextproto;
 967
 968                 /*
 969                  * Too large for the destination or interface;
 970                  * fragment if possible.
 971                  * Must be able to put at least 8 bytes per fragment.
 972                  */
 973                 hlen = unfragpartlen;
 974                 if (mtu > IPV6_MAXPACKET)
 975                         mtu = IPV6_MAXPACKET;
 976
 977                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
 978                 if (len < 8) {
 979                         error = EMSGSIZE;
 980                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
 981                         goto bad;
 982                 }
 983
 984                 /*
 985                  * If the interface will not calculate checksums on
 986                  * fragmented packets, then do it here.
 987                  * XXX-BZ handle the hw offloading case.  Need flags.
 988                  */
 989                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 990                         in6_delayed_cksum(m, plen, hlen);
 991                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 992                 }
 993 #ifdef SCTP
 994                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
 995                         sctp_delayed_cksum(m, hlen);
 996                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 997                 }
 998 #endif
 999                 /*
1000                  * Change the next header field of the last header in the
1001                  * unfragmentable part.
1002                  */
1003                 if (exthdrs.ip6e_rthdr) {
1004                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1005                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1006                 } else if (exthdrs.ip6e_dest1) {
1007                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1008                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1009                 } else if (exthdrs.ip6e_hbh) {
1010                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1011                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1012                 } else {
1013                         nextproto = ip6->ip6_nxt;
1014                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1015                 }
1016
1017                 /*
1018                  * Loop through length of segment after first fragment,
1019                  * make new header and copy data of each part and link onto
1020                  * chain.
1021                  */
1022                 m0 = m;
1023                 id = htonl(ip6_randomid());
1024                 if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
1025                         goto sendorfree;
1026
1027                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1028         }
1029
1030         /*
1031          * Remove leading garbages.
1032          */
1033 sendorfree:
1034         m = m0->m_nextpkt;
1035         m0->m_nextpkt = 0;
1036         m_freem(m0);
1037         for (m0 = m; m; m = m0) {
1038                 m0 = m->m_nextpkt;
1039                 m->m_nextpkt = 0;
1040                 if (error == 0) {
1041                         /* Record statistics for this interface address. */
1042                         if (ia) {
1043                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1044                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1045                                     m->m_pkthdr.len);
1046                         }
1047                         error = nd6_output_ifp(ifp, origifp, m, dst,
1048                             (struct route *)ro);
1049                 } else
1050                         m_freem(m);
1051         }
1052
1053         if (error == 0)
1054                 IP6STAT_INC(ip6s_fragmented);
1055
1056 done:
1057         /*
1058          * Release the route if using our private route, or if
1059          * (with flowtable) we don't have our own reference.
1060          */
1061         if (ro == &ip6route || ro->ro_flags & RT_NORTREF)
1062                 RO_RTFREE(ro);
1063         return (error);
1064
1065 freehdrs:
1066         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1067         m_freem(exthdrs.ip6e_dest1);
1068         m_freem(exthdrs.ip6e_rthdr);
1069         m_freem(exthdrs.ip6e_dest2);
1070         /* FALLTHROUGH */
1071 bad:
1072         if (m)
1073                 m_freem(m);
1074         goto done;
1075 }
1076
1077 static int
1078 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1079 {
1080         struct mbuf *m;
1081
1082         if (hlen > MCLBYTES)
1083                 return (ENOBUFS); /* XXX */
1084
1085         if (hlen > MLEN)
1086                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1087         else
1088                 m = m_get(M_NOWAIT, MT_DATA);
1089         if (m == NULL)
1090                 return (ENOBUFS);
1091         m->m_len = hlen;
1092         if (hdr)
1093                 bcopy(hdr, mtod(m, caddr_t), hlen);
1094
1095         *mp = m;
1096         return (0);
1097 }
1098
1099 /*
1100  * Insert jumbo payload option.
1101  */
1102 static int
1103 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1104 {
1105         struct mbuf *mopt;
1106         u_char *optbuf;
1107         u_int32_t v;
1108
1109 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1110
1111         /*
1112          * If there is no hop-by-hop options header, allocate new one.
1113          * If there is one but it doesn't have enough space to store the
1114          * jumbo payload option, allocate a cluster to store the whole options.
1115          * Otherwise, use it to store the options.
1116          */
1117         if (exthdrs->ip6e_hbh == NULL) {
1118                 mopt = m_get(M_NOWAIT, MT_DATA);
1119                 if (mopt == NULL)
1120                         return (ENOBUFS);
1121                 mopt->m_len = JUMBOOPTLEN;
1122                 optbuf = mtod(mopt, u_char *);
1123                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1124                 exthdrs->ip6e_hbh = mopt;
1125         } else {
1126                 struct ip6_hbh *hbh;
1127
1128                 mopt = exthdrs->ip6e_hbh;
1129                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1130                         /*
1131                          * XXX assumption:
1132                          * - exthdrs->ip6e_hbh is not referenced from places
1133                          *   other than exthdrs.
1134                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1135                          */
1136                         int oldoptlen = mopt->m_len;
1137                         struct mbuf *n;
1138
1139                         /*
1140                          * XXX: give up if the whole (new) hbh header does
1141                          * not fit even in an mbuf cluster.
1142                          */
1143                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1144                                 return (ENOBUFS);
1145
1146                         /*
1147                          * As a consequence, we must always prepare a cluster
1148                          * at this point.
1149                          */
1150                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1151                         if (n == NULL)
1152                                 return (ENOBUFS);
1153                         n->m_len = oldoptlen + JUMBOOPTLEN;
1154                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1155                             oldoptlen);
1156                         optbuf = mtod(n, caddr_t) + oldoptlen;
1157                         m_freem(mopt);
1158                         mopt = exthdrs->ip6e_hbh = n;
1159                 } else {
1160                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1161                         mopt->m_len += JUMBOOPTLEN;
1162                 }
1163                 optbuf[0] = IP6OPT_PADN;
1164                 optbuf[1] = 1;
1165
1166                 /*
1167                  * Adjust the header length according to the pad and
1168                  * the jumbo payload option.
1169                  */
1170                 hbh = mtod(mopt, struct ip6_hbh *);
1171                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1172         }
1173
1174         /* fill in the option. */
1175         optbuf[2] = IP6OPT_JUMBO;
1176         optbuf[3] = 4;
1177         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1178         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1179
1180         /* finally, adjust the packet header length */
1181         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1182
1183         return (0);
1184 #undef JUMBOOPTLEN
1185 }
1186
1187 /*
1188  * Insert fragment header and copy unfragmentable header portions.
1189  */
1190 static int
1191 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1192     struct ip6_frag **frghdrp)
1193 {
1194         struct mbuf *n, *mlast;
1195
1196         if (hlen > sizeof(struct ip6_hdr)) {
1197                 n = m_copym(m0, sizeof(struct ip6_hdr),
1198                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1199                 if (n == NULL)
1200                         return (ENOBUFS);
1201                 m->m_next = n;
1202         } else
1203                 n = m;
1204
1205         /* Search for the last mbuf of unfragmentable part. */
1206         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1207                 ;
1208
1209         if (M_WRITABLE(mlast) &&
1210             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1211                 /* use the trailing space of the last mbuf for the fragment hdr */
1212                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1213                     mlast->m_len);
1214                 mlast->m_len += sizeof(struct ip6_frag);
1215                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1216         } else {
1217                 /* allocate a new mbuf for the fragment header */
1218                 struct mbuf *mfrg;
1219
1220                 mfrg = m_get(M_NOWAIT, MT_DATA);
1221                 if (mfrg == NULL)
1222                         return (ENOBUFS);
1223                 mfrg->m_len = sizeof(struct ip6_frag);
1224                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1225                 mlast->m_next = mfrg;
1226         }
1227
1228         return (0);
1229 }
1230
1231 /*
1232  * Calculates IPv6 path mtu for destination @dst.
1233  * Resulting MTU is stored in @mtup.
1234  *
1235  * Returns 0 on success.
1236  */
1237 static int
1238 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1239 {
1240         struct nhop6_extended nh6;
1241         struct in6_addr kdst;
1242         uint32_t scopeid;
1243         struct ifnet *ifp;
1244         u_long mtu;
1245         int error;
1246
1247         in6_splitscope(dst, &kdst, &scopeid);
1248         if (fib6_lookup_nh_ext(fibnum, &kdst, scopeid, NHR_REF, 0, &nh6) != 0)
1249                 return (EHOSTUNREACH);
1250
1251         ifp = nh6.nh_ifp;
1252         mtu = nh6.nh_mtu;
1253
1254         error = ip6_calcmtu(ifp, dst, mtu, mtup, NULL);
1255         fib6_free_nh_ext(fibnum, &nh6);
1256
1257         return (error);
1258 }
1259
1260 /*
1261  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1262  * and cached data in @ro_pmtu.
1263  * MTU from (successful) route lookup is saved (along with dst)
1264  * inside @ro_pmtu to avoid subsequent route lookups after packet
1265  * filter processing.
1266  *
1267  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1268  * Returns 0 on success.
1269  */
1270 static int
1271 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1272     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1273     int *alwaysfragp, u_int fibnum)
1274 {
1275         struct nhop6_basic nh6;
1276         struct in6_addr kdst;
1277         uint32_t scopeid;
1278         struct sockaddr_in6 *sa6_dst;
1279         u_long mtu;
1280
1281         mtu = 0;
1282         if (do_lookup) {
1283
1284                 /*
1285                  * Here ro_pmtu has final destination address, while
1286                  * ro might represent immediate destination.
1287                  * Use ro_pmtu destination since mtu might differ.
1288                  */
1289                 sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1290                 if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1291                         ro_pmtu->ro_mtu = 0;
1292
1293                 if (ro_pmtu->ro_mtu == 0) {
1294                         bzero(sa6_dst, sizeof(*sa6_dst));
1295                         sa6_dst->sin6_family = AF_INET6;
1296                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1297                         sa6_dst->sin6_addr = *dst;
1298
1299                         in6_splitscope(dst, &kdst, &scopeid);
1300                         if (fib6_lookup_nh_basic(fibnum, &kdst, scopeid, 0, 0,
1301                             &nh6) == 0)
1302                                 ro_pmtu->ro_mtu = nh6.nh_mtu;
1303                 }
1304
1305                 mtu = ro_pmtu->ro_mtu;
1306         }
1307
1308         if (ro_pmtu->ro_rt)
1309                 mtu = ro_pmtu->ro_rt->rt_mtu;
1310
1311         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp));
1312 }
1313
1314 /*
1315  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1316  * hostcache data for @dst.
1317  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1318  *
1319  * Returns 0 on success.
1320  */
1321 static int
1322 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1323     u_long *mtup, int *alwaysfragp)
1324 {
1325         u_long mtu = 0;
1326         int alwaysfrag = 0;
1327         int error = 0;
1328
1329         if (rt_mtu > 0) {
1330                 u_int32_t ifmtu;
1331                 struct in_conninfo inc;
1332
1333                 bzero(&inc, sizeof(inc));
1334                 inc.inc_flags |= INC_ISIPV6;
1335                 inc.inc6_faddr = *dst;
1336
1337                 ifmtu = IN6_LINKMTU(ifp);
1338                 mtu = tcp_hc_getmtu(&inc);
1339                 if (mtu)
1340                         mtu = min(mtu, rt_mtu);
1341                 else
1342                         mtu = rt_mtu;
1343                 if (mtu == 0)
1344                         mtu = ifmtu;
1345                 else if (mtu < IPV6_MMTU) {
1346                         /*
1347                          * RFC2460 section 5, last paragraph:
1348                          * if we record ICMPv6 too big message with
1349                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1350                          * or smaller, with framgent header attached.
1351                          * (fragment header is needed regardless from the
1352                          * packet size, for translators to identify packets)
1353                          */
1354                         alwaysfrag = 1;
1355                         mtu = IPV6_MMTU;
1356                 }
1357         } else if (ifp) {
1358                 mtu = IN6_LINKMTU(ifp);
1359         } else
1360                 error = EHOSTUNREACH; /* XXX */
1361
1362         *mtup = mtu;
1363         if (alwaysfragp)
1364                 *alwaysfragp = alwaysfrag;
1365         return (error);
1366 }
1367
1368 /*
1369  * IP6 socket option processing.
1370  */
1371 int
1372 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1373 {
1374         int optdatalen, uproto;
1375         void *optdata;
1376         struct inpcb *in6p = sotoinpcb(so);
1377         int error, optval;
1378         int level, op, optname;
1379         int optlen;
1380         struct thread *td;
1381 #ifdef  RSS
1382         uint32_t rss_bucket;
1383         int retval;
1384 #endif
1385
1386         level = sopt->sopt_level;
1387         op = sopt->sopt_dir;
1388         optname = sopt->sopt_name;
1389         optlen = sopt->sopt_valsize;
1390         td = sopt->sopt_td;
1391         error = 0;
1392         optval = 0;
1393         uproto = (int)so->so_proto->pr_protocol;
1394
1395         if (level != IPPROTO_IPV6) {
1396                 error = EINVAL;
1397
1398                 if (sopt->sopt_level == SOL_SOCKET &&
1399                     sopt->sopt_dir == SOPT_SET) {
1400                         switch (sopt->sopt_name) {
1401                         case SO_REUSEADDR:
1402                                 INP_WLOCK(in6p);
1403                                 if ((so->so_options & SO_REUSEADDR) != 0)
1404                                         in6p->inp_flags2 |= INP_REUSEADDR;
1405                                 else
1406                                         in6p->inp_flags2 &= ~INP_REUSEADDR;
1407                                 INP_WUNLOCK(in6p);
1408                                 error = 0;
1409                                 break;
1410                         case SO_REUSEPORT:
1411                                 INP_WLOCK(in6p);
1412                                 if ((so->so_options & SO_REUSEPORT) != 0)
1413                                         in6p->inp_flags2 |= INP_REUSEPORT;
1414                                 else
1415                                         in6p->inp_flags2 &= ~INP_REUSEPORT;
1416                                 INP_WUNLOCK(in6p);
1417                                 error = 0;
1418                                 break;
1419                         case SO_SETFIB:
1420                                 INP_WLOCK(in6p);
1421                                 in6p->inp_inc.inc_fibnum = so->so_fibnum;
1422                                 INP_WUNLOCK(in6p);
1423                                 error = 0;
1424                                 break;
1425                         default:
1426                                 break;
1427                         }
1428                 }
1429         } else {                /* level == IPPROTO_IPV6 */
1430                 switch (op) {
1431
1432                 case SOPT_SET:
1433                         switch (optname) {
1434                         case IPV6_2292PKTOPTIONS:
1435 #ifdef IPV6_PKTOPTIONS
1436                         case IPV6_PKTOPTIONS:
1437 #endif
1438                         {
1439                                 struct mbuf *m;
1440
1441                                 error = soopt_getm(sopt, &m); /* XXX */
1442                                 if (error != 0)
1443                                         break;
1444                                 error = soopt_mcopyin(sopt, m); /* XXX */
1445                                 if (error != 0)
1446                                         break;
1447                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1448                                                     m, so, sopt);
1449                                 m_freem(m); /* XXX */
1450                                 break;
1451                         }
1452
1453                         /*
1454                          * Use of some Hop-by-Hop options or some
1455                          * Destination options, might require special
1456                          * privilege.  That is, normal applications
1457                          * (without special privilege) might be forbidden
1458                          * from setting certain options in outgoing packets,
1459                          * and might never see certain options in received
1460                          * packets. [RFC 2292 Section 6]
1461                          * KAME specific note:
1462                          *  KAME prevents non-privileged users from sending or
1463                          *  receiving ANY hbh/dst options in order to avoid
1464                          *  overhead of parsing options in the kernel.
1465                          */
1466                         case IPV6_RECVHOPOPTS:
1467                         case IPV6_RECVDSTOPTS:
1468                         case IPV6_RECVRTHDRDSTOPTS:
1469                                 if (td != NULL) {
1470                                         error = priv_check(td,
1471                                             PRIV_NETINET_SETHDROPTS);
1472                                         if (error)
1473                                                 break;
1474                                 }
1475                                 /* FALLTHROUGH */
1476                         case IPV6_UNICAST_HOPS:
1477                         case IPV6_HOPLIMIT:
1478
1479                         case IPV6_RECVPKTINFO:
1480                         case IPV6_RECVHOPLIMIT:
1481                         case IPV6_RECVRTHDR:
1482                         case IPV6_RECVPATHMTU:
1483                         case IPV6_RECVTCLASS:
1484                         case IPV6_RECVFLOWID:
1485 #ifdef  RSS
1486                         case IPV6_RECVRSSBUCKETID:
1487 #endif
1488                         case IPV6_V6ONLY:
1489                         case IPV6_AUTOFLOWLABEL:
1490                         case IPV6_BINDANY:
1491                         case IPV6_BINDMULTI:
1492 #ifdef  RSS
1493                         case IPV6_RSS_LISTEN_BUCKET:
1494 #endif
1495                                 if (optname == IPV6_BINDANY && td != NULL) {
1496                                         error = priv_check(td,
1497                                             PRIV_NETINET_BINDANY);
1498                                         if (error)
1499                                                 break;
1500                                 }
1501
1502                                 if (optlen != sizeof(int)) {
1503                                         error = EINVAL;
1504                                         break;
1505                                 }
1506                                 error = sooptcopyin(sopt, &optval,
1507                                         sizeof optval, sizeof optval);
1508                                 if (error)
1509                                         break;
1510                                 switch (optname) {
1511
1512                                 case IPV6_UNICAST_HOPS:
1513                                         if (optval < -1 || optval >= 256)
1514                                                 error = EINVAL;
1515                                         else {
1516                                                 /* -1 = kernel default */
1517                                                 in6p->in6p_hops = optval;
1518                                                 if ((in6p->inp_vflag &
1519                                                      INP_IPV4) != 0)
1520                                                         in6p->inp_ip_ttl = optval;
1521                                         }
1522                                         break;
1523 #define OPTSET(bit) \
1524 do { \
1525         INP_WLOCK(in6p); \
1526         if (optval) \
1527                 in6p->inp_flags |= (bit); \
1528         else \
1529                 in6p->inp_flags &= ~(bit); \
1530         INP_WUNLOCK(in6p); \
1531 } while (/*CONSTCOND*/ 0)
1532 #define OPTSET2292(bit) \
1533 do { \
1534         INP_WLOCK(in6p); \
1535         in6p->inp_flags |= IN6P_RFC2292; \
1536         if (optval) \
1537                 in6p->inp_flags |= (bit); \
1538         else \
1539                 in6p->inp_flags &= ~(bit); \
1540         INP_WUNLOCK(in6p); \
1541 } while (/*CONSTCOND*/ 0)
1542 #define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0)
1543
1544 #define OPTSET2(bit, val) do {                                          \
1545         INP_WLOCK(in6p);                                                \
1546         if (val)                                                        \
1547                 in6p->inp_flags2 |= bit;                                \
1548         else                                                            \
1549                 in6p->inp_flags2 &= ~bit;                               \
1550         INP_WUNLOCK(in6p);                                              \
1551 } while (0)
1552 #define OPTBIT2(bit) (in6p->inp_flags2 & (bit) ? 1 : 0)
1553
1554                                 case IPV6_RECVPKTINFO:
1555                                         /* cannot mix with RFC2292 */
1556                                         if (OPTBIT(IN6P_RFC2292)) {
1557                                                 error = EINVAL;
1558                                                 break;
1559                                         }
1560                                         OPTSET(IN6P_PKTINFO);
1561                                         break;
1562
1563                                 case IPV6_HOPLIMIT:
1564                                 {
1565                                         struct ip6_pktopts **optp;
1566
1567                                         /* cannot mix with RFC2292 */
1568                                         if (OPTBIT(IN6P_RFC2292)) {
1569                                                 error = EINVAL;
1570                                                 break;
1571                                         }
1572                                         optp = &in6p->in6p_outputopts;
1573                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1574                                             (u_char *)&optval, sizeof(optval),
1575                                             optp, (td != NULL) ? td->td_ucred :
1576                                             NULL, uproto);
1577                                         break;
1578                                 }
1579
1580                                 case IPV6_RECVHOPLIMIT:
1581                                         /* cannot mix with RFC2292 */
1582                                         if (OPTBIT(IN6P_RFC2292)) {
1583                                                 error = EINVAL;
1584                                                 break;
1585                                         }
1586                                         OPTSET(IN6P_HOPLIMIT);
1587                                         break;
1588
1589                                 case IPV6_RECVHOPOPTS:
1590                                         /* cannot mix with RFC2292 */
1591                                         if (OPTBIT(IN6P_RFC2292)) {
1592                                                 error = EINVAL;
1593                                                 break;
1594                                         }
1595                                         OPTSET(IN6P_HOPOPTS);
1596                                         break;
1597
1598                                 case IPV6_RECVDSTOPTS:
1599                                         /* cannot mix with RFC2292 */
1600                                         if (OPTBIT(IN6P_RFC2292)) {
1601                                                 error = EINVAL;
1602                                                 break;
1603                                         }
1604                                         OPTSET(IN6P_DSTOPTS);
1605                                         break;
1606
1607                                 case IPV6_RECVRTHDRDSTOPTS:
1608                                         /* cannot mix with RFC2292 */
1609                                         if (OPTBIT(IN6P_RFC2292)) {
1610                                                 error = EINVAL;
1611                                                 break;
1612                                         }
1613                                         OPTSET(IN6P_RTHDRDSTOPTS);
1614                                         break;
1615
1616                                 case IPV6_RECVRTHDR:
1617                                         /* cannot mix with RFC2292 */
1618                                         if (OPTBIT(IN6P_RFC2292)) {
1619                                                 error = EINVAL;
1620                                                 break;
1621                                         }
1622                                         OPTSET(IN6P_RTHDR);
1623                                         break;
1624
1625                                 case IPV6_RECVPATHMTU:
1626                                         /*
1627                                          * We ignore this option for TCP
1628                                          * sockets.
1629                                          * (RFC3542 leaves this case
1630                                          * unspecified.)
1631                                          */
1632                                         if (uproto != IPPROTO_TCP)
1633                                                 OPTSET(IN6P_MTU);
1634                                         break;
1635
1636                                 case IPV6_RECVFLOWID:
1637                                         OPTSET2(INP_RECVFLOWID, optval);
1638                                         break;
1639
1640 #ifdef  RSS
1641                                 case IPV6_RECVRSSBUCKETID:
1642                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1643                                         break;
1644 #endif
1645
1646                                 case IPV6_V6ONLY:
1647                                         /*
1648                                          * make setsockopt(IPV6_V6ONLY)
1649                                          * available only prior to bind(2).
1650                                          * see ipng mailing list, Jun 22 2001.
1651                                          */
1652                                         if (in6p->inp_lport ||
1653                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
1654                                                 error = EINVAL;
1655                                                 break;
1656                                         }
1657                                         OPTSET(IN6P_IPV6_V6ONLY);
1658                                         if (optval)
1659                                                 in6p->inp_vflag &= ~INP_IPV4;
1660                                         else
1661                                                 in6p->inp_vflag |= INP_IPV4;
1662                                         break;
1663                                 case IPV6_RECVTCLASS:
1664                                         /* cannot mix with RFC2292 XXX */
1665                                         if (OPTBIT(IN6P_RFC2292)) {
1666                                                 error = EINVAL;
1667                                                 break;
1668                                         }
1669                                         OPTSET(IN6P_TCLASS);
1670                                         break;
1671                                 case IPV6_AUTOFLOWLABEL:
1672                                         OPTSET(IN6P_AUTOFLOWLABEL);
1673                                         break;
1674
1675                                 case IPV6_BINDANY:
1676                                         OPTSET(INP_BINDANY);
1677                                         break;
1678
1679                                 case IPV6_BINDMULTI:
1680                                         OPTSET2(INP_BINDMULTI, optval);
1681                                         break;
1682 #ifdef  RSS
1683                                 case IPV6_RSS_LISTEN_BUCKET:
1684                                         if ((optval >= 0) &&
1685                                             (optval < rss_getnumbuckets())) {
1686                                                 in6p->inp_rss_listen_bucket = optval;
1687                                                 OPTSET2(INP_RSS_BUCKET_SET, 1);
1688                                         } else {
1689                                                 error = EINVAL;
1690                                         }
1691                                         break;
1692 #endif
1693                                 }
1694                                 break;
1695
1696                         case IPV6_TCLASS:
1697                         case IPV6_DONTFRAG:
1698                         case IPV6_USE_MIN_MTU:
1699                         case IPV6_PREFER_TEMPADDR:
1700                                 if (optlen != sizeof(optval)) {
1701                                         error = EINVAL;
1702                                         break;
1703                                 }
1704                                 error = sooptcopyin(sopt, &optval,
1705                                         sizeof optval, sizeof optval);
1706                                 if (error)
1707                                         break;
1708                                 {
1709                                         struct ip6_pktopts **optp;
1710                                         optp = &in6p->in6p_outputopts;
1711                                         error = ip6_pcbopt(optname,
1712                                             (u_char *)&optval, sizeof(optval),
1713                                             optp, (td != NULL) ? td->td_ucred :
1714                                             NULL, uproto);
1715                                         break;
1716                                 }
1717
1718                         case IPV6_2292PKTINFO:
1719                         case IPV6_2292HOPLIMIT:
1720                         case IPV6_2292HOPOPTS:
1721                         case IPV6_2292DSTOPTS:
1722                         case IPV6_2292RTHDR:
1723                                 /* RFC 2292 */
1724                                 if (optlen != sizeof(int)) {
1725                                         error = EINVAL;
1726                                         break;
1727                                 }
1728                                 error = sooptcopyin(sopt, &optval,
1729                                         sizeof optval, sizeof optval);
1730                                 if (error)
1731                                         break;
1732                                 switch (optname) {
1733                                 case IPV6_2292PKTINFO:
1734                                         OPTSET2292(IN6P_PKTINFO);
1735                                         break;
1736                                 case IPV6_2292HOPLIMIT:
1737                                         OPTSET2292(IN6P_HOPLIMIT);
1738                                         break;
1739                                 case IPV6_2292HOPOPTS:
1740                                         /*
1741                                          * Check super-user privilege.
1742                                          * See comments for IPV6_RECVHOPOPTS.
1743                                          */
1744                                         if (td != NULL) {
1745                                                 error = priv_check(td,
1746                                                     PRIV_NETINET_SETHDROPTS);
1747                                                 if (error)
1748                                                         return (error);
1749                                         }
1750                                         OPTSET2292(IN6P_HOPOPTS);
1751                                         break;
1752                                 case IPV6_2292DSTOPTS:
1753                                         if (td != NULL) {
1754                                                 error = priv_check(td,
1755                                                     PRIV_NETINET_SETHDROPTS);
1756                                                 if (error)
1757                                                         return (error);
1758                                         }
1759                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1760                                         break;
1761                                 case IPV6_2292RTHDR:
1762                                         OPTSET2292(IN6P_RTHDR);
1763                                         break;
1764                                 }
1765                                 break;
1766                         case IPV6_PKTINFO:
1767                         case IPV6_HOPOPTS:
1768                         case IPV6_RTHDR:
1769                         case IPV6_DSTOPTS:
1770                         case IPV6_RTHDRDSTOPTS:
1771                         case IPV6_NEXTHOP:
1772                         {
1773                                 /* new advanced API (RFC3542) */
1774                                 u_char *optbuf;
1775                                 u_char optbuf_storage[MCLBYTES];
1776                                 int optlen;
1777                                 struct ip6_pktopts **optp;
1778
1779                                 /* cannot mix with RFC2292 */
1780                                 if (OPTBIT(IN6P_RFC2292)) {
1781                                         error = EINVAL;
1782                                         break;
1783                                 }
1784
1785                                 /*
1786                                  * We only ensure valsize is not too large
1787                                  * here.  Further validation will be done
1788                                  * later.
1789                                  */
1790                                 error = sooptcopyin(sopt, optbuf_storage,
1791                                     sizeof(optbuf_storage), 0);
1792                                 if (error)
1793                                         break;
1794                                 optlen = sopt->sopt_valsize;
1795                                 optbuf = optbuf_storage;
1796                                 optp = &in6p->in6p_outputopts;
1797                                 error = ip6_pcbopt(optname, optbuf, optlen,
1798                                     optp, (td != NULL) ? td->td_ucred : NULL,
1799                                     uproto);
1800                                 break;
1801                         }
1802 #undef OPTSET
1803
1804                         case IPV6_MULTICAST_IF:
1805                         case IPV6_MULTICAST_HOPS:
1806                         case IPV6_MULTICAST_LOOP:
1807                         case IPV6_JOIN_GROUP:
1808                         case IPV6_LEAVE_GROUP:
1809                         case IPV6_MSFILTER:
1810                         case MCAST_BLOCK_SOURCE:
1811                         case MCAST_UNBLOCK_SOURCE:
1812                         case MCAST_JOIN_GROUP:
1813                         case MCAST_LEAVE_GROUP:
1814                         case MCAST_JOIN_SOURCE_GROUP:
1815                         case MCAST_LEAVE_SOURCE_GROUP:
1816                                 error = ip6_setmoptions(in6p, sopt);
1817                                 break;
1818
1819                         case IPV6_PORTRANGE:
1820                                 error = sooptcopyin(sopt, &optval,
1821                                     sizeof optval, sizeof optval);
1822                                 if (error)
1823                                         break;
1824
1825                                 INP_WLOCK(in6p);
1826                                 switch (optval) {
1827                                 case IPV6_PORTRANGE_DEFAULT:
1828                                         in6p->inp_flags &= ~(INP_LOWPORT);
1829                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1830                                         break;
1831
1832                                 case IPV6_PORTRANGE_HIGH:
1833                                         in6p->inp_flags &= ~(INP_LOWPORT);
1834                                         in6p->inp_flags |= INP_HIGHPORT;
1835                                         break;
1836
1837                                 case IPV6_PORTRANGE_LOW:
1838                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1839                                         in6p->inp_flags |= INP_LOWPORT;
1840                                         break;
1841
1842                                 default:
1843                                         error = EINVAL;
1844                                         break;
1845                                 }
1846                                 INP_WUNLOCK(in6p);
1847                                 break;
1848
1849 #ifdef IPSEC
1850                         case IPV6_IPSEC_POLICY:
1851                         {
1852                                 caddr_t req;
1853                                 struct mbuf *m;
1854
1855                                 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1856                                         break;
1857                                 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1858                                         break;
1859                                 req = mtod(m, caddr_t);
1860                                 error = ipsec_set_policy(in6p, optname, req,
1861                                     m->m_len, (sopt->sopt_td != NULL) ?
1862                                     sopt->sopt_td->td_ucred : NULL);
1863                                 m_freem(m);
1864                                 break;
1865                         }
1866 #endif /* IPSEC */
1867
1868                         default:
1869                                 error = ENOPROTOOPT;
1870                                 break;
1871                         }
1872                         break;
1873
1874                 case SOPT_GET:
1875                         switch (optname) {
1876
1877                         case IPV6_2292PKTOPTIONS:
1878 #ifdef IPV6_PKTOPTIONS
1879                         case IPV6_PKTOPTIONS:
1880 #endif
1881                                 /*
1882                                  * RFC3542 (effectively) deprecated the
1883                                  * semantics of the 2292-style pktoptions.
1884                                  * Since it was not reliable in nature (i.e.,
1885                                  * applications had to expect the lack of some
1886                                  * information after all), it would make sense
1887                                  * to simplify this part by always returning
1888                                  * empty data.
1889                                  */
1890                                 sopt->sopt_valsize = 0;
1891                                 break;
1892
1893                         case IPV6_RECVHOPOPTS:
1894                         case IPV6_RECVDSTOPTS:
1895                         case IPV6_RECVRTHDRDSTOPTS:
1896                         case IPV6_UNICAST_HOPS:
1897                         case IPV6_RECVPKTINFO:
1898                         case IPV6_RECVHOPLIMIT:
1899                         case IPV6_RECVRTHDR:
1900                         case IPV6_RECVPATHMTU:
1901
1902                         case IPV6_V6ONLY:
1903                         case IPV6_PORTRANGE:
1904                         case IPV6_RECVTCLASS:
1905                         case IPV6_AUTOFLOWLABEL:
1906                         case IPV6_BINDANY:
1907                         case IPV6_FLOWID:
1908                         case IPV6_FLOWTYPE:
1909                         case IPV6_RECVFLOWID:
1910 #ifdef  RSS
1911                         case IPV6_RSSBUCKETID:
1912                         case IPV6_RECVRSSBUCKETID:
1913 #endif
1914                         case IPV6_BINDMULTI:
1915                                 switch (optname) {
1916
1917                                 case IPV6_RECVHOPOPTS:
1918                                         optval = OPTBIT(IN6P_HOPOPTS);
1919                                         break;
1920
1921                                 case IPV6_RECVDSTOPTS:
1922                                         optval = OPTBIT(IN6P_DSTOPTS);
1923                                         break;
1924
1925                                 case IPV6_RECVRTHDRDSTOPTS:
1926                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
1927                                         break;
1928
1929                                 case IPV6_UNICAST_HOPS:
1930                                         optval = in6p->in6p_hops;
1931                                         break;
1932
1933                                 case IPV6_RECVPKTINFO:
1934                                         optval = OPTBIT(IN6P_PKTINFO);
1935                                         break;
1936
1937                                 case IPV6_RECVHOPLIMIT:
1938                                         optval = OPTBIT(IN6P_HOPLIMIT);
1939                                         break;
1940
1941                                 case IPV6_RECVRTHDR:
1942                                         optval = OPTBIT(IN6P_RTHDR);
1943                                         break;
1944
1945                                 case IPV6_RECVPATHMTU:
1946                                         optval = OPTBIT(IN6P_MTU);
1947                                         break;
1948
1949                                 case IPV6_V6ONLY:
1950                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
1951                                         break;
1952
1953                                 case IPV6_PORTRANGE:
1954                                     {
1955                                         int flags;
1956                                         flags = in6p->inp_flags;
1957                                         if (flags & INP_HIGHPORT)
1958                                                 optval = IPV6_PORTRANGE_HIGH;
1959                                         else if (flags & INP_LOWPORT)
1960                                                 optval = IPV6_PORTRANGE_LOW;
1961                                         else
1962                                                 optval = 0;
1963                                         break;
1964                                     }
1965                                 case IPV6_RECVTCLASS:
1966                                         optval = OPTBIT(IN6P_TCLASS);
1967                                         break;
1968
1969                                 case IPV6_AUTOFLOWLABEL:
1970                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
1971                                         break;
1972
1973                                 case IPV6_BINDANY:
1974                                         optval = OPTBIT(INP_BINDANY);
1975                                         break;
1976
1977                                 case IPV6_FLOWID:
1978                                         optval = in6p->inp_flowid;
1979                                         break;
1980
1981                                 case IPV6_FLOWTYPE:
1982                                         optval = in6p->inp_flowtype;
1983                                         break;
1984
1985                                 case IPV6_RECVFLOWID:
1986                                         optval = OPTBIT2(INP_RECVFLOWID);
1987                                         break;
1988 #ifdef  RSS
1989                                 case IPV6_RSSBUCKETID:
1990                                         retval =
1991                                             rss_hash2bucket(in6p->inp_flowid,
1992                                             in6p->inp_flowtype,
1993                                             &rss_bucket);
1994                                         if (retval == 0)
1995                                                 optval = rss_bucket;
1996                                         else
1997                                                 error = EINVAL;
1998                                         break;
1999
2000                                 case IPV6_RECVRSSBUCKETID:
2001                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2002                                         break;
2003 #endif
2004
2005                                 case IPV6_BINDMULTI:
2006                                         optval = OPTBIT2(INP_BINDMULTI);
2007                                         break;
2008
2009                                 }
2010                                 if (error)
2011                                         break;
2012                                 error = sooptcopyout(sopt, &optval,
2013                                         sizeof optval);
2014                                 break;
2015
2016                         case IPV6_PATHMTU:
2017                         {
2018                                 u_long pmtu = 0;
2019                                 struct ip6_mtuinfo mtuinfo;
2020
2021                                 if (!(so->so_state & SS_ISCONNECTED))
2022                                         return (ENOTCONN);
2023                                 /*
2024                                  * XXX: we dot not consider the case of source
2025                                  * routing, or optional information to specify
2026                                  * the outgoing interface.
2027                                  */
2028                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2029                                     &in6p->in6p_faddr, &pmtu);
2030                                 if (error)
2031                                         break;
2032                                 if (pmtu > IPV6_MAXPACKET)
2033                                         pmtu = IPV6_MAXPACKET;
2034
2035                                 bzero(&mtuinfo, sizeof(mtuinfo));
2036                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2037                                 optdata = (void *)&mtuinfo;
2038                                 optdatalen = sizeof(mtuinfo);
2039                                 error = sooptcopyout(sopt, optdata,
2040                                     optdatalen);
2041                                 break;
2042                         }
2043
2044                         case IPV6_2292PKTINFO:
2045                         case IPV6_2292HOPLIMIT:
2046                         case IPV6_2292HOPOPTS:
2047                         case IPV6_2292RTHDR:
2048                         case IPV6_2292DSTOPTS:
2049                                 switch (optname) {
2050                                 case IPV6_2292PKTINFO:
2051                                         optval = OPTBIT(IN6P_PKTINFO);
2052                                         break;
2053                                 case IPV6_2292HOPLIMIT:
2054                                         optval = OPTBIT(IN6P_HOPLIMIT);
2055                                         break;
2056                                 case IPV6_2292HOPOPTS:
2057                                         optval = OPTBIT(IN6P_HOPOPTS);
2058                                         break;
2059                                 case IPV6_2292RTHDR:
2060                                         optval = OPTBIT(IN6P_RTHDR);
2061                                         break;
2062                                 case IPV6_2292DSTOPTS:
2063                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2064                                         break;
2065                                 }
2066                                 error = sooptcopyout(sopt, &optval,
2067                                     sizeof optval);
2068                                 break;
2069                         case IPV6_PKTINFO:
2070                         case IPV6_HOPOPTS:
2071                         case IPV6_RTHDR:
2072                         case IPV6_DSTOPTS:
2073                         case IPV6_RTHDRDSTOPTS:
2074                         case IPV6_NEXTHOP:
2075                         case IPV6_TCLASS:
2076                         case IPV6_DONTFRAG:
2077                         case IPV6_USE_MIN_MTU:
2078                         case IPV6_PREFER_TEMPADDR:
2079                                 error = ip6_getpcbopt(in6p->in6p_outputopts,
2080                                     optname, sopt);
2081                                 break;
2082
2083                         case IPV6_MULTICAST_IF:
2084                         case IPV6_MULTICAST_HOPS:
2085                         case IPV6_MULTICAST_LOOP:
2086                         case IPV6_MSFILTER:
2087                                 error = ip6_getmoptions(in6p, sopt);
2088                                 break;
2089
2090 #ifdef IPSEC
2091                         case IPV6_IPSEC_POLICY:
2092                           {
2093                                 caddr_t req = NULL;
2094                                 size_t len = 0;
2095                                 struct mbuf *m = NULL;
2096                                 struct mbuf **mp = &m;
2097                                 size_t ovalsize = sopt->sopt_valsize;
2098                                 caddr_t oval = (caddr_t)sopt->sopt_val;
2099
2100                                 error = soopt_getm(sopt, &m); /* XXX */
2101                                 if (error != 0)
2102                                         break;
2103                                 error = soopt_mcopyin(sopt, m); /* XXX */
2104                                 if (error != 0)
2105                                         break;
2106                                 sopt->sopt_valsize = ovalsize;
2107                                 sopt->sopt_val = oval;
2108                                 if (m) {
2109                                         req = mtod(m, caddr_t);
2110                                         len = m->m_len;
2111                                 }
2112                                 error = ipsec_get_policy(in6p, req, len, mp);
2113                                 if (error == 0)
2114                                         error = soopt_mcopyout(sopt, m); /* XXX */
2115                                 if (error == 0 && m)
2116                                         m_freem(m);
2117                                 break;
2118                           }
2119 #endif /* IPSEC */
2120
2121                         default:
2122                                 error = ENOPROTOOPT;
2123                                 break;
2124                         }
2125                         break;
2126                 }
2127         }
2128         return (error);
2129 }
2130
2131 int
2132 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2133 {
2134         int error = 0, optval, optlen;
2135         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2136         struct inpcb *in6p = sotoinpcb(so);
2137         int level, op, optname;
2138
2139         level = sopt->sopt_level;
2140         op = sopt->sopt_dir;
2141         optname = sopt->sopt_name;
2142         optlen = sopt->sopt_valsize;
2143
2144         if (level != IPPROTO_IPV6) {
2145                 return (EINVAL);
2146         }
2147
2148         switch (optname) {
2149         case IPV6_CHECKSUM:
2150                 /*
2151                  * For ICMPv6 sockets, no modification allowed for checksum
2152                  * offset, permit "no change" values to help existing apps.
2153                  *
2154                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2155                  * for an ICMPv6 socket will fail."
2156                  * The current behavior does not meet RFC3542.
2157                  */
2158                 switch (op) {
2159                 case SOPT_SET:
2160                         if (optlen != sizeof(int)) {
2161                                 error = EINVAL;
2162                                 break;
2163                         }
2164                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2165                                             sizeof(optval));
2166                         if (error)
2167                                 break;
2168                         if ((optval % 2) != 0) {
2169                                 /* the API assumes even offset values */
2170                                 error = EINVAL;
2171                         } else if (so->so_proto->pr_protocol ==
2172                             IPPROTO_ICMPV6) {
2173                                 if (optval != icmp6off)
2174                                         error = EINVAL;
2175                         } else
2176                                 in6p->in6p_cksum = optval;
2177                         break;
2178
2179                 case SOPT_GET:
2180                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2181                                 optval = icmp6off;
2182                         else
2183                                 optval = in6p->in6p_cksum;
2184
2185                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2186                         break;
2187
2188                 default:
2189                         error = EINVAL;
2190                         break;
2191                 }
2192                 break;
2193
2194         default:
2195                 error = ENOPROTOOPT;
2196                 break;
2197         }
2198
2199         return (error);
2200 }
2201
2202 /*
2203  * Set up IP6 options in pcb for insertion in output packets or
2204  * specifying behavior of outgoing packets.
2205  */
2206 static int
2207 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2208     struct socket *so, struct sockopt *sopt)
2209 {
2210         struct ip6_pktopts *opt = *pktopt;
2211         int error = 0;
2212         struct thread *td = sopt->sopt_td;
2213
2214         /* turn off any old options. */
2215         if (opt) {
2216 #ifdef DIAGNOSTIC
2217                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2218                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2219                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2220                         printf("ip6_pcbopts: all specified options are cleared.\n");
2221 #endif
2222                 ip6_clearpktopts(opt, -1);
2223         } else
2224                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2225         *pktopt = NULL;
2226
2227         if (!m || m->m_len == 0) {
2228                 /*
2229                  * Only turning off any previous options, regardless of
2230                  * whether the opt is just created or given.
2231                  */
2232                 free(opt, M_IP6OPT);
2233                 return (0);
2234         }
2235
2236         /*  set options specified by user. */
2237         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2238             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2239                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2240                 free(opt, M_IP6OPT);
2241                 return (error);
2242         }
2243         *pktopt = opt;
2244         return (0);
2245 }
2246
2247 /*
2248  * initialize ip6_pktopts.  beware that there are non-zero default values in
2249  * the struct.
2250  */
2251 void
2252 ip6_initpktopts(struct ip6_pktopts *opt)
2253 {
2254
2255         bzero(opt, sizeof(*opt));
2256         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2257         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2258         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2259         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2260 }
2261
2262 static int
2263 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2264     struct ucred *cred, int uproto)
2265 {
2266         struct ip6_pktopts *opt;
2267
2268         if (*pktopt == NULL) {
2269                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2270                     M_WAITOK);
2271                 ip6_initpktopts(*pktopt);
2272         }
2273         opt = *pktopt;
2274
2275         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2276 }
2277
2278 static int
2279 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt)
2280 {
2281         void *optdata = NULL;
2282         int optdatalen = 0;
2283         struct ip6_ext *ip6e;
2284         int error = 0;
2285         struct in6_pktinfo null_pktinfo;
2286         int deftclass = 0, on;
2287         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2288         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2289
2290         switch (optname) {
2291         case IPV6_PKTINFO:
2292                 optdata = (void *)&null_pktinfo;
2293                 if (pktopt && pktopt->ip6po_pktinfo) {
2294                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2295                             sizeof(null_pktinfo));
2296                         in6_clearscope(&null_pktinfo.ipi6_addr);
2297                 } else {
2298                         /* XXX: we don't have to do this every time... */
2299                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2300                 }
2301                 optdatalen = sizeof(struct in6_pktinfo);
2302                 break;
2303         case IPV6_TCLASS:
2304                 if (pktopt && pktopt->ip6po_tclass >= 0)
2305                         optdata = (void *)&pktopt->ip6po_tclass;
2306                 else
2307                         optdata = (void *)&deftclass;
2308                 optdatalen = sizeof(int);
2309                 break;
2310         case IPV6_HOPOPTS:
2311                 if (pktopt && pktopt->ip6po_hbh) {
2312                         optdata = (void *)pktopt->ip6po_hbh;
2313                         ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
2314                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2315                 }
2316                 break;
2317         case IPV6_RTHDR:
2318                 if (pktopt && pktopt->ip6po_rthdr) {
2319                         optdata = (void *)pktopt->ip6po_rthdr;
2320                         ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
2321                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2322                 }
2323                 break;
2324         case IPV6_RTHDRDSTOPTS:
2325                 if (pktopt && pktopt->ip6po_dest1) {
2326                         optdata = (void *)pktopt->ip6po_dest1;
2327                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
2328                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2329                 }
2330                 break;
2331         case IPV6_DSTOPTS:
2332                 if (pktopt && pktopt->ip6po_dest2) {
2333                         optdata = (void *)pktopt->ip6po_dest2;
2334                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
2335                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2336                 }
2337                 break;
2338         case IPV6_NEXTHOP:
2339                 if (pktopt && pktopt->ip6po_nexthop) {
2340                         optdata = (void *)pktopt->ip6po_nexthop;
2341                         optdatalen = pktopt->ip6po_nexthop->sa_len;
2342                 }
2343                 break;
2344         case IPV6_USE_MIN_MTU:
2345                 if (pktopt)
2346                         optdata = (void *)&pktopt->ip6po_minmtu;
2347                 else
2348                         optdata = (void *)&defminmtu;
2349                 optdatalen = sizeof(int);
2350                 break;
2351         case IPV6_DONTFRAG:
2352                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2353                         on = 1;
2354                 else
2355                         on = 0;
2356                 optdata = (void *)&on;
2357                 optdatalen = sizeof(on);
2358                 break;
2359         case IPV6_PREFER_TEMPADDR:
2360                 if (pktopt)
2361                         optdata = (void *)&pktopt->ip6po_prefer_tempaddr;
2362                 else
2363                         optdata = (void *)&defpreftemp;
2364                 optdatalen = sizeof(int);
2365                 break;
2366         default:                /* should not happen */
2367 #ifdef DIAGNOSTIC
2368                 panic("ip6_getpcbopt: unexpected option\n");
2369 #endif
2370                 return (ENOPROTOOPT);
2371         }
2372
2373         error = sooptcopyout(sopt, optdata, optdatalen);
2374
2375         return (error);
2376 }
2377
2378 void
2379 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2380 {
2381         if (pktopt == NULL)
2382                 return;
2383
2384         if (optname == -1 || optname == IPV6_PKTINFO) {
2385                 if (pktopt->ip6po_pktinfo)
2386                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2387                 pktopt->ip6po_pktinfo = NULL;
2388         }
2389         if (optname == -1 || optname == IPV6_HOPLIMIT)
2390                 pktopt->ip6po_hlim = -1;
2391         if (optname == -1 || optname == IPV6_TCLASS)
2392                 pktopt->ip6po_tclass = -1;
2393         if (optname == -1 || optname == IPV6_NEXTHOP) {
2394                 if (pktopt->ip6po_nextroute.ro_rt) {
2395                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2396                         pktopt->ip6po_nextroute.ro_rt = NULL;
2397                 }
2398                 if (pktopt->ip6po_nexthop)
2399                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2400                 pktopt->ip6po_nexthop = NULL;
2401         }
2402         if (optname == -1 || optname == IPV6_HOPOPTS) {
2403                 if (pktopt->ip6po_hbh)
2404                         free(pktopt->ip6po_hbh, M_IP6OPT);
2405                 pktopt->ip6po_hbh = NULL;
2406         }
2407         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2408                 if (pktopt->ip6po_dest1)
2409                         free(pktopt->ip6po_dest1, M_IP6OPT);
2410                 pktopt->ip6po_dest1 = NULL;
2411         }
2412         if (optname == -1 || optname == IPV6_RTHDR) {
2413                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2414                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2415                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2416                 if (pktopt->ip6po_route.ro_rt) {
2417                         RTFREE(pktopt->ip6po_route.ro_rt);
2418                         pktopt->ip6po_route.ro_rt = NULL;
2419                 }
2420         }
2421         if (optname == -1 || optname == IPV6_DSTOPTS) {
2422                 if (pktopt->ip6po_dest2)
2423                         free(pktopt->ip6po_dest2, M_IP6OPT);
2424                 pktopt->ip6po_dest2 = NULL;
2425         }
2426 }
2427
2428 #define PKTOPT_EXTHDRCPY(type) \
2429 do {\
2430         if (src->type) {\
2431                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2432                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2433                 if (dst->type == NULL && canwait == M_NOWAIT)\
2434                         goto bad;\
2435                 bcopy(src->type, dst->type, hlen);\
2436         }\
2437 } while (/*CONSTCOND*/ 0)
2438
2439 static int
2440 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2441 {
2442         if (dst == NULL || src == NULL)  {
2443                 printf("ip6_clearpktopts: invalid argument\n");
2444                 return (EINVAL);
2445         }
2446
2447         dst->ip6po_hlim = src->ip6po_hlim;
2448         dst->ip6po_tclass = src->ip6po_tclass;
2449         dst->ip6po_flags = src->ip6po_flags;
2450         dst->ip6po_minmtu = src->ip6po_minmtu;
2451         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2452         if (src->ip6po_pktinfo) {
2453                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2454                     M_IP6OPT, canwait);
2455                 if (dst->ip6po_pktinfo == NULL)
2456                         goto bad;
2457                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2458         }
2459         if (src->ip6po_nexthop) {
2460                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2461                     M_IP6OPT, canwait);
2462                 if (dst->ip6po_nexthop == NULL)
2463                         goto bad;
2464                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2465                     src->ip6po_nexthop->sa_len);
2466         }
2467         PKTOPT_EXTHDRCPY(ip6po_hbh);
2468         PKTOPT_EXTHDRCPY(ip6po_dest1);
2469         PKTOPT_EXTHDRCPY(ip6po_dest2);
2470         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2471         return (0);
2472
2473   bad:
2474         ip6_clearpktopts(dst, -1);
2475         return (ENOBUFS);
2476 }
2477 #undef PKTOPT_EXTHDRCPY
2478
2479 struct ip6_pktopts *
2480 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2481 {
2482         int error;
2483         struct ip6_pktopts *dst;
2484
2485         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2486         if (dst == NULL)
2487                 return (NULL);
2488         ip6_initpktopts(dst);
2489
2490         if ((error = copypktopts(dst, src, canwait)) != 0) {
2491                 free(dst, M_IP6OPT);
2492                 return (NULL);
2493         }
2494
2495         return (dst);
2496 }
2497
2498 void
2499 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2500 {
2501         if (pktopt == NULL)
2502                 return;
2503
2504         ip6_clearpktopts(pktopt, -1);
2505
2506         free(pktopt, M_IP6OPT);
2507 }
2508
2509 /*
2510  * Set IPv6 outgoing packet options based on advanced API.
2511  */
2512 int
2513 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2514     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2515 {
2516         struct cmsghdr *cm = NULL;
2517
2518         if (control == NULL || opt == NULL)
2519                 return (EINVAL);
2520
2521         ip6_initpktopts(opt);
2522         if (stickyopt) {
2523                 int error;
2524
2525                 /*
2526                  * If stickyopt is provided, make a local copy of the options
2527                  * for this particular packet, then override them by ancillary
2528                  * objects.
2529                  * XXX: copypktopts() does not copy the cached route to a next
2530                  * hop (if any).  This is not very good in terms of efficiency,
2531                  * but we can allow this since this option should be rarely
2532                  * used.
2533                  */
2534                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2535                         return (error);
2536         }
2537
2538         /*
2539          * XXX: Currently, we assume all the optional information is stored
2540          * in a single mbuf.
2541          */
2542         if (control->m_next)
2543                 return (EINVAL);
2544
2545         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2546             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2547                 int error;
2548
2549                 if (control->m_len < CMSG_LEN(0))
2550                         return (EINVAL);
2551
2552                 cm = mtod(control, struct cmsghdr *);
2553                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2554                         return (EINVAL);
2555                 if (cm->cmsg_level != IPPROTO_IPV6)
2556                         continue;
2557
2558                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2559                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2560                 if (error)
2561                         return (error);
2562         }
2563
2564         return (0);
2565 }
2566
2567 /*
2568  * Set a particular packet option, as a sticky option or an ancillary data
2569  * item.  "len" can be 0 only when it's a sticky option.
2570  * We have 4 cases of combination of "sticky" and "cmsg":
2571  * "sticky=0, cmsg=0": impossible
2572  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2573  * "sticky=1, cmsg=0": RFC3542 socket option
2574  * "sticky=1, cmsg=1": RFC2292 socket option
2575  */
2576 static int
2577 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2578     struct ucred *cred, int sticky, int cmsg, int uproto)
2579 {
2580         int minmtupolicy, preftemp;
2581         int error;
2582
2583         if (!sticky && !cmsg) {
2584 #ifdef DIAGNOSTIC
2585                 printf("ip6_setpktopt: impossible case\n");
2586 #endif
2587                 return (EINVAL);
2588         }
2589
2590         /*
2591          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2592          * not be specified in the context of RFC3542.  Conversely,
2593          * RFC3542 types should not be specified in the context of RFC2292.
2594          */
2595         if (!cmsg) {
2596                 switch (optname) {
2597                 case IPV6_2292PKTINFO:
2598                 case IPV6_2292HOPLIMIT:
2599                 case IPV6_2292NEXTHOP:
2600                 case IPV6_2292HOPOPTS:
2601                 case IPV6_2292DSTOPTS:
2602                 case IPV6_2292RTHDR:
2603                 case IPV6_2292PKTOPTIONS:
2604                         return (ENOPROTOOPT);
2605                 }
2606         }
2607         if (sticky && cmsg) {
2608                 switch (optname) {
2609                 case IPV6_PKTINFO:
2610                 case IPV6_HOPLIMIT:
2611                 case IPV6_NEXTHOP:
2612                 case IPV6_HOPOPTS:
2613                 case IPV6_DSTOPTS:
2614                 case IPV6_RTHDRDSTOPTS:
2615                 case IPV6_RTHDR:
2616                 case IPV6_USE_MIN_MTU:
2617                 case IPV6_DONTFRAG:
2618                 case IPV6_TCLASS:
2619                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2620                         return (ENOPROTOOPT);
2621                 }
2622         }
2623
2624         switch (optname) {
2625         case IPV6_2292PKTINFO:
2626         case IPV6_PKTINFO:
2627         {
2628                 struct ifnet *ifp = NULL;
2629                 struct in6_pktinfo *pktinfo;
2630
2631                 if (len != sizeof(struct in6_pktinfo))
2632                         return (EINVAL);
2633
2634                 pktinfo = (struct in6_pktinfo *)buf;
2635
2636                 /*
2637                  * An application can clear any sticky IPV6_PKTINFO option by
2638                  * doing a "regular" setsockopt with ipi6_addr being
2639                  * in6addr_any and ipi6_ifindex being zero.
2640                  * [RFC 3542, Section 6]
2641                  */
2642                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2643                     pktinfo->ipi6_ifindex == 0 &&
2644                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2645                         ip6_clearpktopts(opt, optname);
2646                         break;
2647                 }
2648
2649                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2650                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2651                         return (EINVAL);
2652                 }
2653                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2654                         return (EINVAL);
2655                 /* validate the interface index if specified. */
2656                 if (pktinfo->ipi6_ifindex > V_if_index)
2657                          return (ENXIO);
2658                 if (pktinfo->ipi6_ifindex) {
2659                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2660                         if (ifp == NULL)
2661                                 return (ENXIO);
2662                 }
2663                 if (ifp != NULL && (
2664                     ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED))
2665                         return (ENETDOWN);
2666
2667                 if (ifp != NULL &&
2668                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2669                         struct in6_ifaddr *ia;
2670
2671                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2672                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2673                         if (ia == NULL)
2674                                 return (EADDRNOTAVAIL);
2675                         ifa_free(&ia->ia_ifa);
2676                 }
2677                 /*
2678                  * We store the address anyway, and let in6_selectsrc()
2679                  * validate the specified address.  This is because ipi6_addr
2680                  * may not have enough information about its scope zone, and
2681                  * we may need additional information (such as outgoing
2682                  * interface or the scope zone of a destination address) to
2683                  * disambiguate the scope.
2684                  * XXX: the delay of the validation may confuse the
2685                  * application when it is used as a sticky option.
2686                  */
2687                 if (opt->ip6po_pktinfo == NULL) {
2688                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2689                             M_IP6OPT, M_NOWAIT);
2690                         if (opt->ip6po_pktinfo == NULL)
2691                                 return (ENOBUFS);
2692                 }
2693                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2694                 break;
2695         }
2696
2697         case IPV6_2292HOPLIMIT:
2698         case IPV6_HOPLIMIT:
2699         {
2700                 int *hlimp;
2701
2702                 /*
2703                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2704                  * to simplify the ordering among hoplimit options.
2705                  */
2706                 if (optname == IPV6_HOPLIMIT && sticky)
2707                         return (ENOPROTOOPT);
2708
2709                 if (len != sizeof(int))
2710                         return (EINVAL);
2711                 hlimp = (int *)buf;
2712                 if (*hlimp < -1 || *hlimp > 255)
2713                         return (EINVAL);
2714
2715                 opt->ip6po_hlim = *hlimp;
2716                 break;
2717         }
2718
2719         case IPV6_TCLASS:
2720         {
2721                 int tclass;
2722
2723                 if (len != sizeof(int))
2724                         return (EINVAL);
2725                 tclass = *(int *)buf;
2726                 if (tclass < -1 || tclass > 255)
2727                         return (EINVAL);
2728
2729                 opt->ip6po_tclass = tclass;
2730                 break;
2731         }
2732
2733         case IPV6_2292NEXTHOP:
2734         case IPV6_NEXTHOP:
2735                 if (cred != NULL) {
2736                         error = priv_check_cred(cred,
2737                             PRIV_NETINET_SETHDROPTS, 0);
2738                         if (error)
2739                                 return (error);
2740                 }
2741
2742                 if (len == 0) { /* just remove the option */
2743                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
2744                         break;
2745                 }
2746
2747                 /* check if cmsg_len is large enough for sa_len */
2748                 if (len < sizeof(struct sockaddr) || len < *buf)
2749                         return (EINVAL);
2750
2751                 switch (((struct sockaddr *)buf)->sa_family) {
2752                 case AF_INET6:
2753                 {
2754                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2755                         int error;
2756
2757                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2758                                 return (EINVAL);
2759
2760                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2761                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2762                                 return (EINVAL);
2763                         }
2764                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2765                             != 0) {
2766                                 return (error);
2767                         }
2768                         break;
2769                 }
2770                 case AF_LINK:   /* should eventually be supported */
2771                 default:
2772                         return (EAFNOSUPPORT);
2773                 }
2774
2775                 /* turn off the previous option, then set the new option. */
2776                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2777                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2778                 if (opt->ip6po_nexthop == NULL)
2779                         return (ENOBUFS);
2780                 bcopy(buf, opt->ip6po_nexthop, *buf);
2781                 break;
2782
2783         case IPV6_2292HOPOPTS:
2784         case IPV6_HOPOPTS:
2785         {
2786                 struct ip6_hbh *hbh;
2787                 int hbhlen;
2788
2789                 /*
2790                  * XXX: We don't allow a non-privileged user to set ANY HbH
2791                  * options, since per-option restriction has too much
2792                  * overhead.
2793                  */
2794                 if (cred != NULL) {
2795                         error = priv_check_cred(cred,
2796                             PRIV_NETINET_SETHDROPTS, 0);
2797                         if (error)
2798                                 return (error);
2799                 }
2800
2801                 if (len == 0) {
2802                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
2803                         break;  /* just remove the option */
2804                 }
2805
2806                 /* message length validation */
2807                 if (len < sizeof(struct ip6_hbh))
2808                         return (EINVAL);
2809                 hbh = (struct ip6_hbh *)buf;
2810                 hbhlen = (hbh->ip6h_len + 1) << 3;
2811                 if (len != hbhlen)
2812                         return (EINVAL);
2813
2814                 /* turn off the previous option, then set the new option. */
2815                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2816                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2817                 if (opt->ip6po_hbh == NULL)
2818                         return (ENOBUFS);
2819                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2820
2821                 break;
2822         }
2823
2824         case IPV6_2292DSTOPTS:
2825         case IPV6_DSTOPTS:
2826         case IPV6_RTHDRDSTOPTS:
2827         {
2828                 struct ip6_dest *dest, **newdest = NULL;
2829                 int destlen;
2830
2831                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
2832                         error = priv_check_cred(cred,
2833                             PRIV_NETINET_SETHDROPTS, 0);
2834                         if (error)
2835                                 return (error);
2836                 }
2837
2838                 if (len == 0) {
2839                         ip6_clearpktopts(opt, optname);
2840                         break;  /* just remove the option */
2841                 }
2842
2843                 /* message length validation */
2844                 if (len < sizeof(struct ip6_dest))
2845                         return (EINVAL);
2846                 dest = (struct ip6_dest *)buf;
2847                 destlen = (dest->ip6d_len + 1) << 3;
2848                 if (len != destlen)
2849                         return (EINVAL);
2850
2851                 /*
2852                  * Determine the position that the destination options header
2853                  * should be inserted; before or after the routing header.
2854                  */
2855                 switch (optname) {
2856                 case IPV6_2292DSTOPTS:
2857                         /*
2858                          * The old advacned API is ambiguous on this point.
2859                          * Our approach is to determine the position based
2860                          * according to the existence of a routing header.
2861                          * Note, however, that this depends on the order of the
2862                          * extension headers in the ancillary data; the 1st
2863                          * part of the destination options header must appear
2864                          * before the routing header in the ancillary data,
2865                          * too.
2866                          * RFC3542 solved the ambiguity by introducing
2867                          * separate ancillary data or option types.
2868                          */
2869                         if (opt->ip6po_rthdr == NULL)
2870                                 newdest = &opt->ip6po_dest1;
2871                         else
2872                                 newdest = &opt->ip6po_dest2;
2873                         break;
2874                 case IPV6_RTHDRDSTOPTS:
2875                         newdest = &opt->ip6po_dest1;
2876                         break;
2877                 case IPV6_DSTOPTS:
2878                         newdest = &opt->ip6po_dest2;
2879                         break;
2880                 }
2881
2882                 /* turn off the previous option, then set the new option. */
2883                 ip6_clearpktopts(opt, optname);
2884                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
2885                 if (*newdest == NULL)
2886                         return (ENOBUFS);
2887                 bcopy(dest, *newdest, destlen);
2888
2889                 break;
2890         }
2891
2892         case IPV6_2292RTHDR:
2893         case IPV6_RTHDR:
2894         {
2895                 struct ip6_rthdr *rth;
2896                 int rthlen;
2897
2898                 if (len == 0) {
2899                         ip6_clearpktopts(opt, IPV6_RTHDR);
2900                         break;  /* just remove the option */
2901                 }
2902
2903                 /* message length validation */
2904                 if (len < sizeof(struct ip6_rthdr))
2905                         return (EINVAL);
2906                 rth = (struct ip6_rthdr *)buf;
2907                 rthlen = (rth->ip6r_len + 1) << 3;
2908                 if (len != rthlen)
2909                         return (EINVAL);
2910
2911                 switch (rth->ip6r_type) {
2912                 case IPV6_RTHDR_TYPE_0:
2913                         if (rth->ip6r_len == 0) /* must contain one addr */
2914                                 return (EINVAL);
2915                         if (rth->ip6r_len % 2) /* length must be even */
2916                                 return (EINVAL);
2917                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2918                                 return (EINVAL);
2919                         break;
2920                 default:
2921                         return (EINVAL);        /* not supported */
2922                 }
2923
2924                 /* turn off the previous option */
2925                 ip6_clearpktopts(opt, IPV6_RTHDR);
2926                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
2927                 if (opt->ip6po_rthdr == NULL)
2928                         return (ENOBUFS);
2929                 bcopy(rth, opt->ip6po_rthdr, rthlen);
2930
2931                 break;
2932         }
2933
2934         case IPV6_USE_MIN_MTU:
2935                 if (len != sizeof(int))
2936                         return (EINVAL);
2937                 minmtupolicy = *(int *)buf;
2938                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
2939                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
2940                     minmtupolicy != IP6PO_MINMTU_ALL) {
2941                         return (EINVAL);
2942                 }
2943                 opt->ip6po_minmtu = minmtupolicy;
2944                 break;
2945
2946         case IPV6_DONTFRAG:
2947                 if (len != sizeof(int))
2948                         return (EINVAL);
2949
2950                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
2951                         /*
2952                          * we ignore this option for TCP sockets.
2953                          * (RFC3542 leaves this case unspecified.)
2954                          */
2955                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
2956                 } else
2957                         opt->ip6po_flags |= IP6PO_DONTFRAG;
2958                 break;
2959
2960         case IPV6_PREFER_TEMPADDR:
2961                 if (len != sizeof(int))
2962                         return (EINVAL);
2963                 preftemp = *(int *)buf;
2964                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
2965                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
2966                     preftemp != IP6PO_TEMPADDR_PREFER) {
2967                         return (EINVAL);
2968                 }
2969                 opt->ip6po_prefer_tempaddr = preftemp;
2970                 break;
2971
2972         default:
2973                 return (ENOPROTOOPT);
2974         } /* end of switch */
2975
2976         return (0);
2977 }
2978
2979 /*
2980  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
2981  * packet to the input queue of a specified interface.  Note that this
2982  * calls the output routine of the loopback "driver", but with an interface
2983  * pointer that might NOT be &loif -- easier than replicating that code here.
2984  */
2985 void
2986 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
2987 {
2988         struct mbuf *copym;
2989         struct ip6_hdr *ip6;
2990
2991         copym = m_copy(m, 0, M_COPYALL);
2992         if (copym == NULL)
2993                 return;
2994
2995         /*
2996          * Make sure to deep-copy IPv6 header portion in case the data
2997          * is in an mbuf cluster, so that we can safely override the IPv6
2998          * header portion later.
2999          */
3000         if (!M_WRITABLE(copym) ||
3001             copym->m_len < sizeof(struct ip6_hdr)) {
3002                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3003                 if (copym == NULL)
3004                         return;
3005         }
3006         ip6 = mtod(copym, struct ip6_hdr *);
3007         /*
3008          * clear embedded scope identifiers if necessary.
3009          * in6_clearscope will touch the addresses only when necessary.
3010          */
3011         in6_clearscope(&ip6->ip6_src);
3012         in6_clearscope(&ip6->ip6_dst);
3013         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3014                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3015                     CSUM_PSEUDO_HDR;
3016                 copym->m_pkthdr.csum_data = 0xffff;
3017         }
3018         if_simloop(ifp, copym, AF_INET6, 0);
3019 }
3020
3021 /*
3022  * Chop IPv6 header off from the payload.
3023  */
3024 static int
3025 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3026 {
3027         struct mbuf *mh;
3028         struct ip6_hdr *ip6;
3029
3030         ip6 = mtod(m, struct ip6_hdr *);
3031         if (m->m_len > sizeof(*ip6)) {
3032                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3033                 if (mh == NULL) {
3034                         m_freem(m);
3035                         return ENOBUFS;
3036                 }
3037                 m_move_pkthdr(mh, m);
3038                 M_ALIGN(mh, sizeof(*ip6));
3039                 m->m_len -= sizeof(*ip6);
3040                 m->m_data += sizeof(*ip6);
3041                 mh->m_next = m;
3042                 m = mh;
3043                 m->m_len = sizeof(*ip6);
3044                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3045         }
3046         exthdrs->ip6e_ip6 = m;
3047         return 0;
3048 }
3049
3050 /*
3051  * Compute IPv6 extension header length.
3052  */
3053 int
3054 ip6_optlen(struct inpcb *in6p)
3055 {
3056         int len;
3057
3058         if (!in6p->in6p_outputopts)
3059                 return 0;
3060
3061         len = 0;
3062 #define elen(x) \
3063     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3064
3065         len += elen(in6p->in6p_outputopts->ip6po_hbh);
3066         if (in6p->in6p_outputopts->ip6po_rthdr)
3067                 /* dest1 is valid with rthdr only */
3068                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
3069         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
3070         len += elen(in6p->in6p_outputopts->ip6po_dest2);
3071         return len;
3072 #undef elen
3073 }