sys/netinet6/ip6_output.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the project nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $
  32  */
  33
  34 /*-
  35  * Copyright (c) 1982, 1986, 1988, 1990, 1993
  36  *      The Regents of the University of California.  All rights reserved.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 3. Neither the name of the University nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  60  * SUCH DAMAGE.
  61  *
  62  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  63  */
  64
  65 #include <sys/cdefs.h>
  66 __FBSDID("$FreeBSD$");
  67
  68 #include "opt_inet.h"
  69 #include "opt_inet6.h"
  70 #include "opt_ipsec.h"
  71 #include "opt_kern_tls.h"
  72 #include "opt_ratelimit.h"
  73 #include "opt_route.h"
  74 #include "opt_rss.h"
  75 #include "opt_sctp.h"
  76
  77 #include <sys/param.h>
  78 #include <sys/kernel.h>
  79 #include <sys/ktls.h>
  80 #include <sys/malloc.h>
  81 #include <sys/mbuf.h>
  82 #include <sys/errno.h>
  83 #include <sys/priv.h>
  84 #include <sys/proc.h>
  85 #include <sys/protosw.h>
  86 #include <sys/socket.h>
  87 #include <sys/socketvar.h>
  88 #include <sys/syslog.h>
  89 #include <sys/ucred.h>
  90
  91 #include <machine/in_cksum.h>
  92
  93 #include <net/if.h>
  94 #include <net/if_var.h>
  95 #include <net/if_vlan_var.h>
  96 #include <net/if_llatbl.h>
  97 #include <net/ethernet.h>
  98 #include <net/netisr.h>
  99 #include <net/route.h>
 100 #include <net/route/nhop.h>
 101 #include <net/pfil.h>
 102 #include <net/rss_config.h>
 103 #include <net/vnet.h>
 104
 105 #include <netinet/in.h>
 106 #include <netinet/in_var.h>
 107 #include <netinet/ip_var.h>
 108 #include <netinet6/in6_fib.h>
 109 #include <netinet6/in6_var.h>
 110 #include <netinet/ip6.h>
 111 #include <netinet/icmp6.h>
 112 #include <netinet6/ip6_var.h>
 113 #include <netinet/in_pcb.h>
 114 #include <netinet/tcp_var.h>
 115 #include <netinet6/nd6.h>
 116 #include <netinet6/in6_rss.h>
 117
 118 #include <netipsec/ipsec_support.h>
 119 #if defined(SCTP) || defined(SCTP_SUPPORT)
 120 #include <netinet/sctp.h>
 121 #include <netinet/sctp_crc32.h>
 122 #endif
 123
 124 #include <netinet6/ip6protosw.h>
 125 #include <netinet6/scope6_var.h>
 126
 127 extern int in6_mcast_loop;
 128
 129 struct ip6_exthdrs {
 130         struct mbuf *ip6e_ip6;
 131         struct mbuf *ip6e_hbh;
 132         struct mbuf *ip6e_dest1;
 133         struct mbuf *ip6e_rthdr;
 134         struct mbuf *ip6e_dest2;
 135 };
 136
 137 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 138
 139 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 140                            struct ucred *, int);
 141 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 142         struct socket *, struct sockopt *);
 143 static int ip6_getpcbopt(struct inpcb *, int, struct sockopt *);
 144 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 145         struct ucred *, int, int, int);
 146
 147 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 148 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 149         struct ip6_frag **);
 150 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 151 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 152 static int ip6_getpmtu(struct route_in6 *, int,
 153         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int,
 154         u_int);
 155 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 156         u_long *, int *, u_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  * Make an extension header from option data.  hp is the source,
 162  * mp is the destination, and _ol is the optlen.
 163  */
 164 #define MAKE_EXTHDR(hp, mp, _ol)                                        \
 165     do {                                                                \
 166         if (hp) {                                                       \
 167                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 168                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 169                     ((eh)->ip6e_len + 1) << 3);                         \
 170                 if (error)                                              \
 171                         goto freehdrs;                                  \
 172                 (_ol) += (*(mp))->m_len;                                \
 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("%s:%d: assumption failed: "\
 188                             "hdr not split: hdrsplit %d exthdrs %p",\
 189                             __func__, __LINE__, hdrsplit, &exthdrs);\
 190                 *mtod((m), u_char *) = *(p);\
 191                 *(p) = (i);\
 192                 p = mtod((m), u_char *);\
 193                 (m)->m_next = (mp)->m_next;\
 194                 (mp)->m_next = (m);\
 195                 (mp) = (m);\
 196         }\
 197     } while (/*CONSTCOND*/ 0)
 198
 199 void
 200 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 201 {
 202         u_short csum;
 203
 204         csum = in_cksum_skip(m, offset + plen, offset);
 205         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 206                 csum = 0xffff;
 207         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 208
 209         if (offset + sizeof(csum) > m->m_len)
 210                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
 211         else
 212                 *(u_short *)mtodo(m, offset) = csum;
 213 }
 214
 215 static void
 216 ip6_output_delayed_csum(struct mbuf *m, struct ifnet *ifp, int csum_flags,
 217     int plen, int optlen)
 218 {
 219
 220         KASSERT((plen >= optlen), ("%s:%d: plen %d < optlen %d, m %p, ifp %p "
 221             "csum_flags %#x",
 222             __func__, __LINE__, plen, optlen, m, ifp, csum_flags));
 223
 224         if (csum_flags & CSUM_DELAY_DATA_IPV6) {
 225                 in6_delayed_cksum(m, plen - optlen,
 226                     sizeof(struct ip6_hdr) + optlen);
 227                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 228         }
 229 #if defined(SCTP) || defined(SCTP_SUPPORT)
 230         if (csum_flags & CSUM_SCTP_IPV6) {
 231                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr) + optlen);
 232                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 233         }
 234 #endif
 235 }
 236
 237 int
 238 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 239     int fraglen , uint32_t id)
 240 {
 241         struct mbuf *m, **mnext, *m_frgpart;
 242         struct ip6_hdr *ip6, *mhip6;
 243         struct ip6_frag *ip6f;
 244         int off;
 245         int error;
 246         int tlen = m0->m_pkthdr.len;
 247
 248         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 249
 250         m = m0;
 251         ip6 = mtod(m, struct ip6_hdr *);
 252         mnext = &m->m_nextpkt;
 253
 254         for (off = hlen; off < tlen; off += fraglen) {
 255                 m = m_gethdr(M_NOWAIT, MT_DATA);
 256                 if (!m) {
 257                         IP6STAT_INC(ip6s_odropped);
 258                         return (ENOBUFS);
 259                 }
 260
 261                 /*
 262                  * Make sure the complete packet header gets copied
 263                  * from the originating mbuf to the newly created
 264                  * mbuf. This also ensures that existing firewall
 265                  * classification(s), VLAN tags and so on get copied
 266                  * to the resulting fragmented packet(s):
 267                  */
 268                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 269                         m_free(m);
 270                         IP6STAT_INC(ip6s_odropped);
 271                         return (ENOBUFS);
 272                 }
 273
 274                 *mnext = m;
 275                 mnext = &m->m_nextpkt;
 276                 m->m_data += max_linkhdr;
 277                 mhip6 = mtod(m, struct ip6_hdr *);
 278                 *mhip6 = *ip6;
 279                 m->m_len = sizeof(*mhip6);
 280                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 281                 if (error) {
 282                         IP6STAT_INC(ip6s_odropped);
 283                         return (error);
 284                 }
 285                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 286                 if (off + fraglen >= tlen)
 287                         fraglen = tlen - off;
 288                 else
 289                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 290                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 291                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 292                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 293                         IP6STAT_INC(ip6s_odropped);
 294                         return (ENOBUFS);
 295                 }
 296                 m_cat(m, m_frgpart);
 297                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 298                 ip6f->ip6f_reserved = 0;
 299                 ip6f->ip6f_ident = id;
 300                 ip6f->ip6f_nxt = nextproto;
 301                 IP6STAT_INC(ip6s_ofragments);
 302                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 303         }
 304
 305         return (0);
 306 }
 307
 308 static int
 309 ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp,
 310     struct mbuf *m, struct sockaddr_in6 *dst, struct route_in6 *ro,
 311     bool stamp_tag)
 312 {
 313 #ifdef KERN_TLS
 314         struct ktls_session *tls = NULL;
 315 #endif
 316         struct m_snd_tag *mst;
 317         int error;
 318
 319         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 320         mst = NULL;
 321
 322 #ifdef KERN_TLS
 323         /*
 324          * If this is an unencrypted TLS record, save a reference to
 325          * the record.  This local reference is used to call
 326          * ktls_output_eagain after the mbuf has been freed (thus
 327          * dropping the mbuf's reference) in if_output.
 328          */
 329         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 330                 tls = ktls_hold(m->m_next->m_epg_tls);
 331                 mst = tls->snd_tag;
 332
 333                 /*
 334                  * If a TLS session doesn't have a valid tag, it must
 335                  * have had an earlier ifp mismatch, so drop this
 336                  * packet.
 337                  */
 338                 if (mst == NULL) {
 339                         error = EAGAIN;
 340                         goto done;
 341                 }
 342                 /*
 343                  * Always stamp tags that include NIC ktls.
 344                  */
 345                 stamp_tag = true;
 346         }
 347 #endif
 348 #ifdef RATELIMIT
 349         if (inp != NULL && mst == NULL) {
 350                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 351                     (inp->inp_snd_tag != NULL &&
 352                     inp->inp_snd_tag->ifp != ifp))
 353                         in_pcboutput_txrtlmt(inp, ifp, m);
 354
 355                 if (inp->inp_snd_tag != NULL)
 356                         mst = inp->inp_snd_tag;
 357         }
 358 #endif
 359         if (stamp_tag && mst != NULL) {
 360                 KASSERT(m->m_pkthdr.rcvif == NULL,
 361                     ("trying to add a send tag to a forwarded packet"));
 362                 if (mst->ifp != ifp) {
 363                         error = EAGAIN;
 364                         goto done;
 365                 }
 366
 367                 /* stamp send tag on mbuf */
 368                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 369                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 370         }
 371
 372         error = nd6_output_ifp(ifp, origifp, m, dst, (struct route *)ro);
 373
 374 done:
 375         /* Check for route change invalidating send tags. */
 376 #ifdef KERN_TLS
 377         if (tls != NULL) {
 378                 if (error == EAGAIN)
 379                         error = ktls_output_eagain(inp, tls);
 380                 ktls_free(tls);
 381         }
 382 #endif
 383 #ifdef RATELIMIT
 384         if (error == EAGAIN)
 385                 in_pcboutput_eagain(inp);
 386 #endif
 387         return (error);
 388 }
 389
 390 /*
 391  * IP6 output.
 392  * The packet in mbuf chain m contains a skeletal IP6 header (with pri, len,
 393  * nxt, hlim, src, dst).
 394  * This function may modify ver and hlim only.
 395  * The mbuf chain containing the packet will be freed.
 396  * The mbuf opt, if present, will not be freed.
 397  * If route_in6 ro is present and has ro_nh initialized, route lookup would be
 398  * skipped and ro->ro_nh would be used. If ro is present but ro->ro_nh is NULL,
 399  * then result of route lookup is stored in ro->ro_nh.
 400  *
 401  * Type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and nd_ifinfo.linkmtu
 402  * is uint32_t.  So we use u_long to hold largest one, which is rt_mtu.
 403  *
 404  * ifpp - XXX: just for statistics
 405  */
 406 int
 407 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 408     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 409     struct ifnet **ifpp, struct inpcb *inp)
 410 {
 411         struct ip6_hdr *ip6;
 412         struct ifnet *ifp, *origifp;
 413         struct mbuf *m = m0;
 414         struct mbuf *mprev;
 415         struct route_in6 *ro_pmtu;
 416         struct nhop_object *nh;
 417         struct sockaddr_in6 *dst, sin6, src_sa, dst_sa;
 418         struct in6_addr odst;
 419         u_char *nexthdrp;
 420         int tlen, len;
 421         int error = 0;
 422         int vlan_pcp = -1;
 423         struct in6_ifaddr *ia = NULL;
 424         u_long mtu;
 425         int alwaysfrag, dontfrag;
 426         u_int32_t optlen, plen = 0, unfragpartlen;
 427         struct ip6_exthdrs exthdrs;
 428         struct in6_addr src0, dst0;
 429         u_int32_t zone;
 430         bool hdrsplit;
 431         int sw_csum, tso;
 432         int needfiblookup;
 433         uint32_t fibnum;
 434         struct m_tag *fwd_tag = NULL;
 435         uint32_t id;
 436
 437         NET_EPOCH_ASSERT();
 438
 439         if (inp != NULL) {
 440                 INP_LOCK_ASSERT(inp);
 441                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 442                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 443                         /* Unconditionally set flowid. */
 444                         m->m_pkthdr.flowid = inp->inp_flowid;
 445                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 446                 }
 447                 if ((inp->inp_flags2 & INP_2PCP_SET) != 0)
 448                         vlan_pcp = (inp->inp_flags2 & INP_2PCP_MASK) >>
 449                             INP_2PCP_SHIFT;
 450 #ifdef NUMA
 451                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 452 #endif
 453         }
 454
 455 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 456         /*
 457          * IPSec checking which handles several cases.
 458          * FAST IPSEC: We re-injected the packet.
 459          * XXX: need scope argument.
 460          */
 461         if (IPSEC_ENABLED(ipv6)) {
 462                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 463                         if (error == EINPROGRESS)
 464                                 error = 0;
 465                         goto done;
 466                 }
 467         }
 468 #endif /* IPSEC */
 469
 470         /* Source address validation. */
 471         ip6 = mtod(m, struct ip6_hdr *);
 472         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 473             (flags & IPV6_UNSPECSRC) == 0) {
 474                 error = EOPNOTSUPP;
 475                 IP6STAT_INC(ip6s_badscope);
 476                 goto bad;
 477         }
 478         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 479                 error = EOPNOTSUPP;
 480                 IP6STAT_INC(ip6s_badscope);
 481                 goto bad;
 482         }
 483
 484         /*
 485          * If we are given packet options to add extension headers prepare them.
 486          * Calculate the total length of the extension header chain.
 487          * Keep the length of the unfragmentable part for fragmentation.
 488          */
 489         bzero(&exthdrs, sizeof(exthdrs));
 490         optlen = 0;
 491         unfragpartlen = sizeof(struct ip6_hdr);
 492         if (opt) {
 493                 /* Hop-by-Hop options header. */
 494                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh, optlen);
 495
 496                 /* Destination options header (1st part). */
 497                 if (opt->ip6po_rthdr) {
 498 #ifndef RTHDR_SUPPORT_IMPLEMENTED
 499                         /*
 500                          * If there is a routing header, discard the packet
 501                          * right away here. RH0/1 are obsolete and we do not
 502                          * currently support RH2/3/4.
 503                          * People trying to use RH253/254 may want to disable
 504                          * this check.
 505                          * The moment we do support any routing header (again)
 506                          * this block should check the routing type more
 507                          * selectively.
 508                          */
 509                         error = EINVAL;
 510                         goto bad;
 511 #endif
 512
 513                         /*
 514                          * Destination options header (1st part).
 515                          * This only makes sense with a routing header.
 516                          * See Section 9.2 of RFC 3542.
 517                          * Disabling this part just for MIP6 convenience is
 518                          * a bad idea.  We need to think carefully about a
 519                          * way to make the advanced API coexist with MIP6
 520                          * options, which might automatically be inserted in
 521                          * the kernel.
 522                          */
 523                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1,
 524                             optlen);
 525                 }
 526                 /* Routing header. */
 527                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr, optlen);
 528
 529                 unfragpartlen += optlen;
 530
 531                 /*
 532                  * NOTE: we don't add AH/ESP length here (done in
 533                  * ip6_ipsec_output()).
 534                  */
 535
 536                 /* Destination options header (2nd part). */
 537                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2, optlen);
 538         }
 539
 540         /*
 541          * If there is at least one extension header,
 542          * separate IP6 header from the payload.
 543          */
 544         hdrsplit = false;
 545         if (optlen) {
 546                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 547                         m = NULL;
 548                         goto freehdrs;
 549                 }
 550                 m = exthdrs.ip6e_ip6;
 551                 ip6 = mtod(m, struct ip6_hdr *);
 552                 hdrsplit = true;
 553         }
 554
 555         /* Adjust mbuf packet header length. */
 556         m->m_pkthdr.len += optlen;
 557         plen = m->m_pkthdr.len - sizeof(*ip6);
 558
 559         /* If this is a jumbo payload, insert a jumbo payload option. */
 560         if (plen > IPV6_MAXPACKET) {
 561                 if (!hdrsplit) {
 562                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 563                                 m = NULL;
 564                                 goto freehdrs;
 565                         }
 566                         m = exthdrs.ip6e_ip6;
 567                         ip6 = mtod(m, struct ip6_hdr *);
 568                         hdrsplit = true;
 569                 }
 570                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 571                         goto freehdrs;
 572                 ip6->ip6_plen = 0;
 573         } else
 574                 ip6->ip6_plen = htons(plen);
 575         nexthdrp = &ip6->ip6_nxt;
 576
 577         if (optlen) {
 578                 /*
 579                  * Concatenate headers and fill in next header fields.
 580                  * Here we have, on "m"
 581                  *      IPv6 payload
 582                  * and we insert headers accordingly.
 583                  * Finally, we should be getting:
 584                  *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload].
 585                  *
 586                  * During the header composing process "m" points to IPv6
 587                  * header.  "mprev" points to an extension header prior to esp.
 588                  */
 589                 mprev = m;
 590
 591                 /*
 592                  * We treat dest2 specially.  This makes IPsec processing
 593                  * much easier.  The goal here is to make mprev point the
 594                  * mbuf prior to dest2.
 595                  *
 596                  * Result: IPv6 dest2 payload.
 597                  * m and mprev will point to IPv6 header.
 598                  */
 599                 if (exthdrs.ip6e_dest2) {
 600                         if (!hdrsplit)
 601                                 panic("%s:%d: assumption failed: "
 602                                     "hdr not split: hdrsplit %d exthdrs %p",
 603                                     __func__, __LINE__, hdrsplit, &exthdrs);
 604                         exthdrs.ip6e_dest2->m_next = m->m_next;
 605                         m->m_next = exthdrs.ip6e_dest2;
 606                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 607                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 608                 }
 609
 610                 /*
 611                  * Result: IPv6 hbh dest1 rthdr dest2 payload.
 612                  * m will point to IPv6 header.  mprev will point to the
 613                  * extension header prior to dest2 (rthdr in the above case).
 614                  */
 615                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 616                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 617                            IPPROTO_DSTOPTS);
 618                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 619                            IPPROTO_ROUTING);
 620         }
 621
 622         IP6STAT_INC(ip6s_localout);
 623
 624         /* Route packet. */
 625         ro_pmtu = ro;
 626         if (opt && opt->ip6po_rthdr)
 627                 ro = &opt->ip6po_route;
 628         if (ro != NULL)
 629                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 630         else
 631                 dst = &sin6;
 632         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 633
 634 again:
 635         /*
 636          * If specified, try to fill in the traffic class field.
 637          * Do not override if a non-zero value is already set.
 638          * We check the diffserv field and the ECN field separately.
 639          */
 640         if (opt && opt->ip6po_tclass >= 0) {
 641                 int mask = 0;
 642
 643                 if (IPV6_DSCP(ip6) == 0)
 644                         mask |= 0xfc;
 645                 if (IPV6_ECN(ip6) == 0)
 646                         mask |= 0x03;
 647                 if (mask != 0)
 648                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 649         }
 650
 651         /* Fill in or override the hop limit field, if necessary. */
 652         if (opt && opt->ip6po_hlim != -1)
 653                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 654         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 655                 if (im6o != NULL)
 656                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 657                 else
 658                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 659         }
 660
 661         if (ro == NULL || ro->ro_nh == NULL) {
 662                 bzero(dst, sizeof(*dst));
 663                 dst->sin6_family = AF_INET6;
 664                 dst->sin6_len = sizeof(*dst);
 665                 dst->sin6_addr = ip6->ip6_dst;
 666         }
 667         /*
 668          * Validate route against routing table changes.
 669          * Make sure that the address family is set in route.
 670          */
 671         nh = NULL;
 672         ifp = NULL;
 673         mtu = 0;
 674         if (ro != NULL) {
 675                 if (ro->ro_nh != NULL && inp != NULL) {
 676                         ro->ro_dst.sin6_family = AF_INET6; /* XXX KASSERT? */
 677                         NH_VALIDATE((struct route *)ro, &inp->inp_rt_cookie,
 678                             fibnum);
 679                 }
 680                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 681                     (!NH_IS_VALID(ro->ro_nh) ||
 682                     ro->ro_dst.sin6_family != AF_INET6 ||
 683                     !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)))
 684                         RO_INVALIDATE_CACHE(ro);
 685
 686                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 687                     ro->ro_dst.sin6_family == AF_INET6 &&
 688                     IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 689                         nh = ro->ro_nh;
 690                         ifp = nh->nh_ifp;
 691                 } else {
 692                         if (ro->ro_lle)
 693                                 LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 694                         ro->ro_lle = NULL;
 695                         if (fwd_tag == NULL) {
 696                                 bzero(&dst_sa, sizeof(dst_sa));
 697                                 dst_sa.sin6_family = AF_INET6;
 698                                 dst_sa.sin6_len = sizeof(dst_sa);
 699                                 dst_sa.sin6_addr = ip6->ip6_dst;
 700                         }
 701                         error = in6_selectroute(&dst_sa, opt, im6o, ro, &ifp,
 702                             &nh, fibnum, m->m_pkthdr.flowid);
 703                         if (error != 0) {
 704                                 IP6STAT_INC(ip6s_noroute);
 705                                 if (ifp != NULL)
 706                                         in6_ifstat_inc(ifp, ifs6_out_discard);
 707                                 goto bad;
 708                         }
 709                         if (ifp != NULL)
 710                             mtu = ifp->if_mtu;
 711                 }
 712                 if (nh == NULL) {
 713                         /*
 714                          * If in6_selectroute() does not return a nexthop
 715                          * dst may not have been updated.
 716                          */
 717                         *dst = dst_sa;  /* XXX */
 718                 } else {
 719                         if (nh->nh_flags & NHF_HOST)
 720                             mtu = nh->nh_mtu;
 721                         ia = (struct in6_ifaddr *)(nh->nh_ifa);
 722                         counter_u64_add(nh->nh_pksent, 1);
 723                 }
 724         } else {
 725                 struct nhop_object *nh;
 726                 struct in6_addr kdst;
 727                 uint32_t scopeid;
 728
 729                 if (fwd_tag == NULL) {
 730                         bzero(&dst_sa, sizeof(dst_sa));
 731                         dst_sa.sin6_family = AF_INET6;
 732                         dst_sa.sin6_len = sizeof(dst_sa);
 733                         dst_sa.sin6_addr = ip6->ip6_dst;
 734                 }
 735
 736                 if (IN6_IS_ADDR_MULTICAST(&dst_sa.sin6_addr) &&
 737                     im6o != NULL &&
 738                     (ifp = im6o->im6o_multicast_ifp) != NULL) {
 739                         /* We do not need a route lookup. */
 740                         *dst = dst_sa;  /* XXX */
 741                         goto nonh6lookup;
 742                 }
 743
 744                 in6_splitscope(&dst_sa.sin6_addr, &kdst, &scopeid);
 745
 746                 if (IN6_IS_ADDR_MC_LINKLOCAL(&dst_sa.sin6_addr) ||
 747                     IN6_IS_ADDR_MC_NODELOCAL(&dst_sa.sin6_addr)) {
 748                         if (scopeid > 0) {
 749                                 ifp = in6_getlinkifnet(scopeid);
 750                                 if (ifp == NULL) {
 751                                         error = EHOSTUNREACH;
 752                                         goto bad;
 753                                 }
 754                                 *dst = dst_sa;  /* XXX */
 755                                 goto nonh6lookup;
 756                         }
 757                 }
 758
 759                 nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE,
 760                     m->m_pkthdr.flowid);
 761                 if (nh == NULL) {
 762                         IP6STAT_INC(ip6s_noroute);
 763                         /* No ifp in6_ifstat_inc(ifp, ifs6_out_discard); */
 764                         error = EHOSTUNREACH;;
 765                         goto bad;
 766                 }
 767
 768                 ifp = nh->nh_ifp;
 769                 mtu = nh->nh_mtu;
 770                 ia = ifatoia6(nh->nh_ifa);
 771                 if (nh->nh_flags & NHF_GATEWAY)
 772                         dst->sin6_addr = nh->gw6_sa.sin6_addr;
 773 nonh6lookup:
 774                 ;
 775         }
 776
 777         /* Then nh (for unicast) and ifp must be non-NULL valid values. */
 778         if ((flags & IPV6_FORWARDING) == 0) {
 779                 /* XXX: the FORWARDING flag can be set for mrouting. */
 780                 in6_ifstat_inc(ifp, ifs6_out_request);
 781         }
 782
 783         /* Setup data structures for scope ID checks. */
 784         src0 = ip6->ip6_src;
 785         bzero(&src_sa, sizeof(src_sa));
 786         src_sa.sin6_family = AF_INET6;
 787         src_sa.sin6_len = sizeof(src_sa);
 788         src_sa.sin6_addr = ip6->ip6_src;
 789
 790         dst0 = ip6->ip6_dst;
 791         /* Re-initialize to be sure. */
 792         bzero(&dst_sa, sizeof(dst_sa));
 793         dst_sa.sin6_family = AF_INET6;
 794         dst_sa.sin6_len = sizeof(dst_sa);
 795         dst_sa.sin6_addr = ip6->ip6_dst;
 796
 797         /* Check for valid scope ID. */
 798         if (in6_setscope(&src0, ifp, &zone) == 0 &&
 799             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 800             in6_setscope(&dst0, ifp, &zone) == 0 &&
 801             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 802                 /*
 803                  * The outgoing interface is in the zone of the source
 804                  * and destination addresses.
 805                  *
 806                  * Because the loopback interface cannot receive
 807                  * packets with a different scope ID than its own,
 808                  * there is a trick to pretend the outgoing packet
 809                  * was received by the real network interface, by
 810                  * setting "origifp" different from "ifp". This is
 811                  * only allowed when "ifp" is a loopback network
 812                  * interface. Refer to code in nd6_output_ifp() for
 813                  * more details.
 814                  */
 815                 origifp = ifp;
 816
 817                 /*
 818                  * We should use ia_ifp to support the case of sending
 819                  * packets to an address of our own.
 820                  */
 821                 if (ia != NULL && ia->ia_ifp)
 822                         ifp = ia->ia_ifp;
 823
 824         } else if ((ifp->if_flags & IFF_LOOPBACK) == 0 ||
 825             sa6_recoverscope(&src_sa) != 0 ||
 826             sa6_recoverscope(&dst_sa) != 0 ||
 827             dst_sa.sin6_scope_id == 0 ||
 828             (src_sa.sin6_scope_id != 0 &&
 829             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 830             (origifp = ifnet_byindex(dst_sa.sin6_scope_id)) == NULL) {
 831                 /*
 832                  * If the destination network interface is not a
 833                  * loopback interface, or the destination network
 834                  * address has no scope ID, or the source address has
 835                  * a scope ID set which is different from the
 836                  * destination address one, or there is no network
 837                  * interface representing this scope ID, the address
 838                  * pair is considered invalid.
 839                  */
 840                 IP6STAT_INC(ip6s_badscope);
 841                 in6_ifstat_inc(ifp, ifs6_out_discard);
 842                 if (error == 0)
 843                         error = EHOSTUNREACH; /* XXX */
 844                 goto bad;
 845         }
 846         /* All scope ID checks are successful. */
 847
 848         if (nh && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 849                 if (opt && opt->ip6po_nextroute.ro_nh) {
 850                         /*
 851                          * The nexthop is explicitly specified by the
 852                          * application.  We assume the next hop is an IPv6
 853                          * address.
 854                          */
 855                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 856                 }
 857                 else if ((nh->nh_flags & NHF_GATEWAY))
 858                         dst = &nh->gw6_sa;
 859         }
 860
 861         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 862                 m->m_flags &= ~(M_BCAST | M_MCAST); /* Just in case. */
 863         } else {
 864                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 865                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 866
 867                 /* Confirm that the outgoing interface supports multicast. */
 868                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 869                         IP6STAT_INC(ip6s_noroute);
 870                         in6_ifstat_inc(ifp, ifs6_out_discard);
 871                         error = ENETUNREACH;
 872                         goto bad;
 873                 }
 874                 if ((im6o == NULL && in6_mcast_loop) ||
 875                     (im6o && im6o->im6o_multicast_loop)) {
 876                         /*
 877                          * Loop back multicast datagram if not expressly
 878                          * forbidden to do so, even if we have not joined
 879                          * the address; protocols will filter it later,
 880                          * thus deferring a hash lookup and lock acquisition
 881                          * at the expense of an m_copym().
 882                          */
 883                         ip6_mloopback(ifp, m);
 884                 } else {
 885                         /*
 886                          * If we are acting as a multicast router, perform
 887                          * multicast forwarding as if the packet had just
 888                          * arrived on the interface to which we are about
 889                          * to send.  The multicast forwarding function
 890                          * recursively calls this function, using the
 891                          * IPV6_FORWARDING flag to prevent infinite recursion.
 892                          *
 893                          * Multicasts that are looped back by ip6_mloopback(),
 894                          * above, will be forwarded by the ip6_input() routine,
 895                          * if necessary.
 896                          */
 897                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 898                                 /*
 899                                  * XXX: ip6_mforward expects that rcvif is NULL
 900                                  * when it is called from the originating path.
 901                                  * However, it may not always be the case.
 902                                  */
 903                                 m->m_pkthdr.rcvif = NULL;
 904                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 905                                         m_freem(m);
 906                                         goto done;
 907                                 }
 908                         }
 909                 }
 910                 /*
 911                  * Multicasts with a hoplimit of zero may be looped back,
 912                  * above, but must not be transmitted on a network.
 913                  * Also, multicasts addressed to the loopback interface
 914                  * are not sent -- the above call to ip6_mloopback() will
 915                  * loop back a copy if this host actually belongs to the
 916                  * destination group on the loopback interface.
 917                  */
 918                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 919                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 920                         m_freem(m);
 921                         goto done;
 922                 }
 923         }
 924
 925         /*
 926          * Fill the outgoing inteface to tell the upper layer
 927          * to increment per-interface statistics.
 928          */
 929         if (ifpp)
 930                 *ifpp = ifp;
 931
 932         /* Determine path MTU. */
 933         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 934                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 935                 goto bad;
 936         KASSERT(mtu > 0, ("%s:%d: mtu %ld, ro_pmtu %p ro %p ifp %p "
 937             "alwaysfrag %d fibnum %u\n", __func__, __LINE__, mtu, ro_pmtu, ro,
 938             ifp, alwaysfrag, fibnum));
 939
 940         /*
 941          * The caller of this function may specify to use the minimum MTU
 942          * in some cases.
 943          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 944          * setting.  The logic is a bit complicated; by default, unicast
 945          * packets will follow path MTU while multicast packets will be sent at
 946          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 947          * including unicast ones will be sent at the minimum MTU.  Multicast
 948          * packets will always be sent at the minimum MTU unless
 949          * IP6PO_MINMTU_DISABLE is explicitly specified.
 950          * See RFC 3542 for more details.
 951          */
 952         if (mtu > IPV6_MMTU) {
 953                 if ((flags & IPV6_MINMTU))
 954                         mtu = IPV6_MMTU;
 955                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 956                         mtu = IPV6_MMTU;
 957                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 958                          (opt == NULL ||
 959                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 960                         mtu = IPV6_MMTU;
 961                 }
 962         }
 963
 964         /*
 965          * Clear embedded scope identifiers if necessary.
 966          * in6_clearscope() will touch the addresses only when necessary.
 967          */
 968         in6_clearscope(&ip6->ip6_src);
 969         in6_clearscope(&ip6->ip6_dst);
 970
 971         /*
 972          * If the outgoing packet contains a hop-by-hop options header,
 973          * it must be examined and processed even by the source node.
 974          * (RFC 2460, section 4.)
 975          */
 976         if (exthdrs.ip6e_hbh) {
 977                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 978                 u_int32_t dummy; /* XXX unused */
 979                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 980
 981 #ifdef DIAGNOSTIC
 982                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 983                         panic("ip6e_hbh is not contiguous");
 984 #endif
 985                 /*
 986                  *  XXX: if we have to send an ICMPv6 error to the sender,
 987                  *       we need the M_LOOP flag since icmp6_error() expects
 988                  *       the IPv6 and the hop-by-hop options header are
 989                  *       contiguous unless the flag is set.
 990                  */
 991                 m->m_flags |= M_LOOP;
 992                 m->m_pkthdr.rcvif = ifp;
 993                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 994                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 995                     &dummy, &plen) < 0) {
 996                         /* m was already freed at this point. */
 997                         error = EINVAL;/* better error? */
 998                         goto done;
 999                 }
1000                 m->m_flags &= ~M_LOOP; /* XXX */
1001                 m->m_pkthdr.rcvif = NULL;
1002         }
1003
1004         /* Jump over all PFIL processing if hooks are not active. */
1005         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
1006                 goto passout;
1007
1008         odst = ip6->ip6_dst;
1009         /* Run through list of hooks for output packets. */
1010         switch (pfil_run_hooks(V_inet6_pfil_head, &m, ifp, PFIL_OUT, inp)) {
1011         case PFIL_PASS:
1012                 ip6 = mtod(m, struct ip6_hdr *);
1013                 break;
1014         case PFIL_DROPPED:
1015                 error = EACCES;
1016                 /* FALLTHROUGH */
1017         case PFIL_CONSUMED:
1018                 goto done;
1019         }
1020
1021         needfiblookup = 0;
1022         /* See if destination IP address was changed by packet filter. */
1023         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
1024                 m->m_flags |= M_SKIP_FIREWALL;
1025                 /* If destination is now ourself drop to ip6_input(). */
1026                 if (in6_localip(&ip6->ip6_dst)) {
1027                         m->m_flags |= M_FASTFWD_OURS;
1028                         if (m->m_pkthdr.rcvif == NULL)
1029                                 m->m_pkthdr.rcvif = V_loif;
1030                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1031                                 m->m_pkthdr.csum_flags |=
1032                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1033                                 m->m_pkthdr.csum_data = 0xffff;
1034                         }
1035 #if defined(SCTP) || defined(SCTP_SUPPORT)
1036                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1037                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1038 #endif
1039                         error = netisr_queue(NETISR_IPV6, m);
1040                         goto done;
1041                 } else {
1042                         if (ro != NULL)
1043                                 RO_INVALIDATE_CACHE(ro);
1044                         needfiblookup = 1; /* Redo the routing table lookup. */
1045                 }
1046         }
1047         /* See if fib was changed by packet filter. */
1048         if (fibnum != M_GETFIB(m)) {
1049                 m->m_flags |= M_SKIP_FIREWALL;
1050                 fibnum = M_GETFIB(m);
1051                 if (ro != NULL)
1052                         RO_INVALIDATE_CACHE(ro);
1053                 needfiblookup = 1;
1054         }
1055         if (needfiblookup)
1056                 goto again;
1057
1058         /* See if local, if yes, send it to netisr. */
1059         if (m->m_flags & M_FASTFWD_OURS) {
1060                 if (m->m_pkthdr.rcvif == NULL)
1061                         m->m_pkthdr.rcvif = V_loif;
1062                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1063                         m->m_pkthdr.csum_flags |=
1064                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1065                         m->m_pkthdr.csum_data = 0xffff;
1066                 }
1067 #if defined(SCTP) || defined(SCTP_SUPPORT)
1068                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1069                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1070 #endif
1071                 error = netisr_queue(NETISR_IPV6, m);
1072                 goto done;
1073         }
1074         /* Or forward to some other address? */
1075         if ((m->m_flags & M_IP6_NEXTHOP) &&
1076             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
1077                 if (ro != NULL)
1078                         dst = (struct sockaddr_in6 *)&ro->ro_dst;
1079                 else
1080                         dst = &sin6;
1081                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
1082                 m->m_flags |= M_SKIP_FIREWALL;
1083                 m->m_flags &= ~M_IP6_NEXTHOP;
1084                 m_tag_delete(m, fwd_tag);
1085                 goto again;
1086         }
1087
1088 passout:
1089         if (vlan_pcp > -1)
1090                 EVL_APPLY_PRI(m, vlan_pcp);
1091
1092         /* Ensure the packet data is mapped if the interface requires it. */
1093         if ((ifp->if_capenable & IFCAP_MEXTPG) == 0) {
1094                 m = mb_unmapped_to_ext(m);
1095                 if (m == NULL) {
1096                         IP6STAT_INC(ip6s_odropped);
1097                         return (ENOBUFS);
1098                 }
1099         }
1100
1101         /*
1102          * Send the packet to the outgoing interface.
1103          * If necessary, do IPv6 fragmentation before sending.
1104          *
1105          * The logic here is rather complex:
1106          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
1107          * 1-a: send as is if tlen <= path mtu
1108          * 1-b: fragment if tlen > path mtu
1109          *
1110          * 2: if user asks us not to fragment (dontfrag == 1)
1111          * 2-a: send as is if tlen <= interface mtu
1112          * 2-b: error if tlen > interface mtu
1113          *
1114          * 3: if we always need to attach fragment header (alwaysfrag == 1)
1115          *      always fragment
1116          *
1117          * 4: if dontfrag == 1 && alwaysfrag == 1
1118          *      error, as we cannot handle this conflicting request.
1119          */
1120         sw_csum = m->m_pkthdr.csum_flags;
1121         if (!hdrsplit) {
1122                 tso = ((sw_csum & ifp->if_hwassist &
1123                     (CSUM_TSO | CSUM_INNER_TSO)) != 0) ? 1 : 0;
1124                 sw_csum &= ~ifp->if_hwassist;
1125         } else
1126                 tso = 0;
1127         /*
1128          * If we added extension headers, we will not do TSO and calculate the
1129          * checksums ourselves for now.
1130          * XXX-BZ  Need a framework to know when the NIC can handle it, even
1131          * with ext. hdrs.
1132          */
1133         ip6_output_delayed_csum(m, ifp, sw_csum, plen, optlen);
1134         /* XXX-BZ m->m_pkthdr.csum_flags &= ~ifp->if_hwassist; */
1135         tlen = m->m_pkthdr.len;
1136
1137         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1138                 dontfrag = 1;
1139         else
1140                 dontfrag = 0;
1141         if (dontfrag && alwaysfrag) {   /* Case 4. */
1142                 /* Conflicting request - can't transmit. */
1143                 error = EMSGSIZE;
1144                 goto bad;
1145         }
1146         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* Case 2-b. */
1147                 /*
1148                  * Even if the DONTFRAG option is specified, we cannot send the
1149                  * packet when the data length is larger than the MTU of the
1150                  * outgoing interface.
1151                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1152                  * application wanted to know the MTU value. Also return an
1153                  * error code (this is not described in the API spec).
1154                  */
1155                 if (inp != NULL)
1156                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1157                 error = EMSGSIZE;
1158                 goto bad;
1159         }
1160
1161         /* Transmit packet without fragmentation. */
1162         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* Cases 1-a and 2-a. */
1163                 struct in6_ifaddr *ia6;
1164
1165                 ip6 = mtod(m, struct ip6_hdr *);
1166                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1167                 if (ia6) {
1168                         /* Record statistics for this interface address. */
1169                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1170                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1171                             m->m_pkthdr.len);
1172                 }
1173                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1174                     (flags & IP_NO_SND_TAG_RL) ? false : true);
1175                 goto done;
1176         }
1177
1178         /* Try to fragment the packet.  Cases 1-b and 3. */
1179         if (mtu < IPV6_MMTU) {
1180                 /* Path MTU cannot be less than IPV6_MMTU. */
1181                 error = EMSGSIZE;
1182                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1183                 goto bad;
1184         } else if (ip6->ip6_plen == 0) {
1185                 /* Jumbo payload cannot be fragmented. */
1186                 error = EMSGSIZE;
1187                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1188                 goto bad;
1189         } else {
1190                 u_char nextproto;
1191
1192                 /*
1193                  * Too large for the destination or interface;
1194                  * fragment if possible.
1195                  * Must be able to put at least 8 bytes per fragment.
1196                  */
1197                 if (mtu > IPV6_MAXPACKET)
1198                         mtu = IPV6_MAXPACKET;
1199
1200                 len = (mtu - unfragpartlen - sizeof(struct ip6_frag)) & ~7;
1201                 if (len < 8) {
1202                         error = EMSGSIZE;
1203                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1204                         goto bad;
1205                 }
1206
1207                 /*
1208                  * If the interface will not calculate checksums on
1209                  * fragmented packets, then do it here.
1210                  * XXX-BZ handle the hw offloading case.  Need flags.
1211                  */
1212                 ip6_output_delayed_csum(m, ifp, m->m_pkthdr.csum_flags, plen,
1213                     optlen);
1214
1215                 /*
1216                  * Change the next header field of the last header in the
1217                  * unfragmentable part.
1218                  */
1219                 if (exthdrs.ip6e_rthdr) {
1220                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1221                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1222                 } else if (exthdrs.ip6e_dest1) {
1223                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1224                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1225                 } else if (exthdrs.ip6e_hbh) {
1226                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1227                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1228                 } else {
1229                         ip6 = mtod(m, struct ip6_hdr *);
1230                         nextproto = ip6->ip6_nxt;
1231                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1232                 }
1233
1234                 /*
1235                  * Loop through length of segment after first fragment,
1236                  * make new header and copy data of each part and link onto
1237                  * chain.
1238                  */
1239                 m0 = m;
1240                 id = htonl(ip6_randomid());
1241                 error = ip6_fragment(ifp, m, unfragpartlen, nextproto,len, id);
1242                 if (error != 0)
1243                         goto sendorfree;
1244
1245                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1246         }
1247
1248         /* Remove leading garbage. */
1249 sendorfree:
1250         m = m0->m_nextpkt;
1251         m0->m_nextpkt = 0;
1252         m_freem(m0);
1253         for (; m; m = m0) {
1254                 m0 = m->m_nextpkt;
1255                 m->m_nextpkt = 0;
1256                 if (error == 0) {
1257                         /* Record statistics for this interface address. */
1258                         if (ia) {
1259                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1260                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1261                                     m->m_pkthdr.len);
1262                         }
1263                         if (vlan_pcp > -1)
1264                                 EVL_APPLY_PRI(m, vlan_pcp);
1265                         error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1266                             true);
1267                 } else
1268                         m_freem(m);
1269         }
1270
1271         if (error == 0)
1272                 IP6STAT_INC(ip6s_fragmented);
1273
1274 done:
1275         return (error);
1276
1277 freehdrs:
1278         m_freem(exthdrs.ip6e_hbh);      /* m_freem() checks if mbuf is NULL. */
1279         m_freem(exthdrs.ip6e_dest1);
1280         m_freem(exthdrs.ip6e_rthdr);
1281         m_freem(exthdrs.ip6e_dest2);
1282         /* FALLTHROUGH */
1283 bad:
1284         if (m)
1285                 m_freem(m);
1286         goto done;
1287 }
1288
1289 static int
1290 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1291 {
1292         struct mbuf *m;
1293
1294         if (hlen > MCLBYTES)
1295                 return (ENOBUFS); /* XXX */
1296
1297         if (hlen > MLEN)
1298                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1299         else
1300                 m = m_get(M_NOWAIT, MT_DATA);
1301         if (m == NULL)
1302                 return (ENOBUFS);
1303         m->m_len = hlen;
1304         if (hdr)
1305                 bcopy(hdr, mtod(m, caddr_t), hlen);
1306
1307         *mp = m;
1308         return (0);
1309 }
1310
1311 /*
1312  * Insert jumbo payload option.
1313  */
1314 static int
1315 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1316 {
1317         struct mbuf *mopt;
1318         u_char *optbuf;
1319         u_int32_t v;
1320
1321 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1322
1323         /*
1324          * If there is no hop-by-hop options header, allocate new one.
1325          * If there is one but it doesn't have enough space to store the
1326          * jumbo payload option, allocate a cluster to store the whole options.
1327          * Otherwise, use it to store the options.
1328          */
1329         if (exthdrs->ip6e_hbh == NULL) {
1330                 mopt = m_get(M_NOWAIT, MT_DATA);
1331                 if (mopt == NULL)
1332                         return (ENOBUFS);
1333                 mopt->m_len = JUMBOOPTLEN;
1334                 optbuf = mtod(mopt, u_char *);
1335                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1336                 exthdrs->ip6e_hbh = mopt;
1337         } else {
1338                 struct ip6_hbh *hbh;
1339
1340                 mopt = exthdrs->ip6e_hbh;
1341                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1342                         /*
1343                          * XXX assumption:
1344                          * - exthdrs->ip6e_hbh is not referenced from places
1345                          *   other than exthdrs.
1346                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1347                          */
1348                         int oldoptlen = mopt->m_len;
1349                         struct mbuf *n;
1350
1351                         /*
1352                          * XXX: give up if the whole (new) hbh header does
1353                          * not fit even in an mbuf cluster.
1354                          */
1355                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1356                                 return (ENOBUFS);
1357
1358                         /*
1359                          * As a consequence, we must always prepare a cluster
1360                          * at this point.
1361                          */
1362                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1363                         if (n == NULL)
1364                                 return (ENOBUFS);
1365                         n->m_len = oldoptlen + JUMBOOPTLEN;
1366                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1367                             oldoptlen);
1368                         optbuf = mtod(n, caddr_t) + oldoptlen;
1369                         m_freem(mopt);
1370                         mopt = exthdrs->ip6e_hbh = n;
1371                 } else {
1372                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1373                         mopt->m_len += JUMBOOPTLEN;
1374                 }
1375                 optbuf[0] = IP6OPT_PADN;
1376                 optbuf[1] = 1;
1377
1378                 /*
1379                  * Adjust the header length according to the pad and
1380                  * the jumbo payload option.
1381                  */
1382                 hbh = mtod(mopt, struct ip6_hbh *);
1383                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1384         }
1385
1386         /* fill in the option. */
1387         optbuf[2] = IP6OPT_JUMBO;
1388         optbuf[3] = 4;
1389         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1390         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1391
1392         /* finally, adjust the packet header length */
1393         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1394
1395         return (0);
1396 #undef JUMBOOPTLEN
1397 }
1398
1399 /*
1400  * Insert fragment header and copy unfragmentable header portions.
1401  */
1402 static int
1403 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1404     struct ip6_frag **frghdrp)
1405 {
1406         struct mbuf *n, *mlast;
1407
1408         if (hlen > sizeof(struct ip6_hdr)) {
1409                 n = m_copym(m0, sizeof(struct ip6_hdr),
1410                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1411                 if (n == NULL)
1412                         return (ENOBUFS);
1413                 m->m_next = n;
1414         } else
1415                 n = m;
1416
1417         /* Search for the last mbuf of unfragmentable part. */
1418         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1419                 ;
1420
1421         if (M_WRITABLE(mlast) &&
1422             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1423                 /* use the trailing space of the last mbuf for the fragment hdr */
1424                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1425                     mlast->m_len);
1426                 mlast->m_len += sizeof(struct ip6_frag);
1427                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1428         } else {
1429                 /* allocate a new mbuf for the fragment header */
1430                 struct mbuf *mfrg;
1431
1432                 mfrg = m_get(M_NOWAIT, MT_DATA);
1433                 if (mfrg == NULL)
1434                         return (ENOBUFS);
1435                 mfrg->m_len = sizeof(struct ip6_frag);
1436                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1437                 mlast->m_next = mfrg;
1438         }
1439
1440         return (0);
1441 }
1442
1443 /*
1444  * Calculates IPv6 path mtu for destination @dst.
1445  * Resulting MTU is stored in @mtup.
1446  *
1447  * Returns 0 on success.
1448  */
1449 static int
1450 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1451 {
1452         struct epoch_tracker et;
1453         struct nhop_object *nh;
1454         struct in6_addr kdst;
1455         uint32_t scopeid;
1456         int error;
1457
1458         in6_splitscope(dst, &kdst, &scopeid);
1459
1460         NET_EPOCH_ENTER(et);
1461         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1462         if (nh != NULL)
1463                 error = ip6_calcmtu(nh->nh_ifp, dst, nh->nh_mtu, mtup, NULL, 0);
1464         else
1465                 error = EHOSTUNREACH;
1466         NET_EPOCH_EXIT(et);
1467
1468         return (error);
1469 }
1470
1471 /*
1472  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1473  * and cached data in @ro_pmtu.
1474  * MTU from (successful) route lookup is saved (along with dst)
1475  * inside @ro_pmtu to avoid subsequent route lookups after packet
1476  * filter processing.
1477  *
1478  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1479  * Returns 0 on success.
1480  */
1481 static int
1482 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1483     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1484     int *alwaysfragp, u_int fibnum, u_int proto)
1485 {
1486         struct nhop_object *nh;
1487         struct in6_addr kdst;
1488         uint32_t scopeid;
1489         struct sockaddr_in6 *sa6_dst, sin6;
1490         u_long mtu;
1491
1492         NET_EPOCH_ASSERT();
1493
1494         mtu = 0;
1495         if (ro_pmtu == NULL || do_lookup) {
1496                 /*
1497                  * Here ro_pmtu has final destination address, while
1498                  * ro might represent immediate destination.
1499                  * Use ro_pmtu destination since mtu might differ.
1500                  */
1501                 if (ro_pmtu != NULL) {
1502                         sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1503                         if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1504                                 ro_pmtu->ro_mtu = 0;
1505                 } else
1506                         sa6_dst = &sin6;
1507
1508                 if (ro_pmtu == NULL || ro_pmtu->ro_mtu == 0) {
1509                         bzero(sa6_dst, sizeof(*sa6_dst));
1510                         sa6_dst->sin6_family = AF_INET6;
1511                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1512                         sa6_dst->sin6_addr = *dst;
1513
1514                         in6_splitscope(dst, &kdst, &scopeid);
1515                         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1516                         if (nh != NULL) {
1517                                 mtu = nh->nh_mtu;
1518                                 if (ro_pmtu != NULL)
1519                                         ro_pmtu->ro_mtu = mtu;
1520                         }
1521                 } else
1522                         mtu = ro_pmtu->ro_mtu;
1523         }
1524
1525         if (ro_pmtu != NULL && ro_pmtu->ro_nh != NULL)
1526                 mtu = ro_pmtu->ro_nh->nh_mtu;
1527
1528         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1529 }
1530
1531 /*
1532  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1533  * hostcache data for @dst.
1534  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1535  *
1536  * Returns 0 on success.
1537  */
1538 static int
1539 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1540     u_long *mtup, int *alwaysfragp, u_int proto)
1541 {
1542         u_long mtu = 0;
1543         int alwaysfrag = 0;
1544         int error = 0;
1545
1546         if (rt_mtu > 0) {
1547                 u_int32_t ifmtu;
1548                 struct in_conninfo inc;
1549
1550                 bzero(&inc, sizeof(inc));
1551                 inc.inc_flags |= INC_ISIPV6;
1552                 inc.inc6_faddr = *dst;
1553
1554                 ifmtu = IN6_LINKMTU(ifp);
1555
1556                 /* TCP is known to react to pmtu changes so skip hc */
1557                 if (proto != IPPROTO_TCP)
1558                         mtu = tcp_hc_getmtu(&inc);
1559
1560                 if (mtu)
1561                         mtu = min(mtu, rt_mtu);
1562                 else
1563                         mtu = rt_mtu;
1564                 if (mtu == 0)
1565                         mtu = ifmtu;
1566                 else if (mtu < IPV6_MMTU) {
1567                         /*
1568                          * RFC2460 section 5, last paragraph:
1569                          * if we record ICMPv6 too big message with
1570                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1571                          * or smaller, with framgent header attached.
1572                          * (fragment header is needed regardless from the
1573                          * packet size, for translators to identify packets)
1574                          */
1575                         alwaysfrag = 1;
1576                         mtu = IPV6_MMTU;
1577                 }
1578         } else if (ifp) {
1579                 mtu = IN6_LINKMTU(ifp);
1580         } else
1581                 error = EHOSTUNREACH; /* XXX */
1582
1583         *mtup = mtu;
1584         if (alwaysfragp)
1585                 *alwaysfragp = alwaysfrag;
1586         return (error);
1587 }
1588
1589 /*
1590  * IP6 socket option processing.
1591  */
1592 int
1593 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1594 {
1595         int optdatalen, uproto;
1596         void *optdata;
1597         struct inpcb *inp = sotoinpcb(so);
1598         int error, optval;
1599         int level, op, optname;
1600         int optlen;
1601         struct thread *td;
1602 #ifdef  RSS
1603         uint32_t rss_bucket;
1604         int retval;
1605 #endif
1606
1607 /*
1608  * Don't use more than a quarter of mbuf clusters.  N.B.:
1609  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1610  * on LP64 architectures, so cast to u_long to avoid undefined
1611  * behavior.  ILP32 architectures cannot have nmbclusters
1612  * large enough to overflow for other reasons.
1613  */
1614 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1615
1616         level = sopt->sopt_level;
1617         op = sopt->sopt_dir;
1618         optname = sopt->sopt_name;
1619         optlen = sopt->sopt_valsize;
1620         td = sopt->sopt_td;
1621         error = 0;
1622         optval = 0;
1623         uproto = (int)so->so_proto->pr_protocol;
1624
1625         if (level != IPPROTO_IPV6) {
1626                 error = EINVAL;
1627
1628                 if (sopt->sopt_level == SOL_SOCKET &&
1629                     sopt->sopt_dir == SOPT_SET) {
1630                         switch (sopt->sopt_name) {
1631                         case SO_REUSEADDR:
1632                                 INP_WLOCK(inp);
1633                                 if ((so->so_options & SO_REUSEADDR) != 0)
1634                                         inp->inp_flags2 |= INP_REUSEADDR;
1635                                 else
1636                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1637                                 INP_WUNLOCK(inp);
1638                                 error = 0;
1639                                 break;
1640                         case SO_REUSEPORT:
1641                                 INP_WLOCK(inp);
1642                                 if ((so->so_options & SO_REUSEPORT) != 0)
1643                                         inp->inp_flags2 |= INP_REUSEPORT;
1644                                 else
1645                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1646                                 INP_WUNLOCK(inp);
1647                                 error = 0;
1648                                 break;
1649                         case SO_REUSEPORT_LB:
1650                                 INP_WLOCK(inp);
1651                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1652                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1653                                 else
1654                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1655                                 INP_WUNLOCK(inp);
1656                                 error = 0;
1657                                 break;
1658                         case SO_SETFIB:
1659                                 INP_WLOCK(inp);
1660                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1661                                 INP_WUNLOCK(inp);
1662                                 error = 0;
1663                                 break;
1664                         case SO_MAX_PACING_RATE:
1665 #ifdef RATELIMIT
1666                                 INP_WLOCK(inp);
1667                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1668                                 INP_WUNLOCK(inp);
1669                                 error = 0;
1670 #else
1671                                 error = EOPNOTSUPP;
1672 #endif
1673                                 break;
1674                         default:
1675                                 break;
1676                         }
1677                 }
1678         } else {                /* level == IPPROTO_IPV6 */
1679                 switch (op) {
1680                 case SOPT_SET:
1681                         switch (optname) {
1682                         case IPV6_2292PKTOPTIONS:
1683 #ifdef IPV6_PKTOPTIONS
1684                         case IPV6_PKTOPTIONS:
1685 #endif
1686                         {
1687                                 struct mbuf *m;
1688
1689                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1690                                         printf("ip6_ctloutput: mbuf limit hit\n");
1691                                         error = ENOBUFS;
1692                                         break;
1693                                 }
1694
1695                                 error = soopt_getm(sopt, &m); /* XXX */
1696                                 if (error != 0)
1697                                         break;
1698                                 error = soopt_mcopyin(sopt, m); /* XXX */
1699                                 if (error != 0)
1700                                         break;
1701                                 INP_WLOCK(inp);
1702                                 error = ip6_pcbopts(&inp->in6p_outputopts, m,
1703                                     so, sopt);
1704                                 INP_WUNLOCK(inp);
1705                                 m_freem(m); /* XXX */
1706                                 break;
1707                         }
1708
1709                         /*
1710                          * Use of some Hop-by-Hop options or some
1711                          * Destination options, might require special
1712                          * privilege.  That is, normal applications
1713                          * (without special privilege) might be forbidden
1714                          * from setting certain options in outgoing packets,
1715                          * and might never see certain options in received
1716                          * packets. [RFC 2292 Section 6]
1717                          * KAME specific note:
1718                          *  KAME prevents non-privileged users from sending or
1719                          *  receiving ANY hbh/dst options in order to avoid
1720                          *  overhead of parsing options in the kernel.
1721                          */
1722                         case IPV6_RECVHOPOPTS:
1723                         case IPV6_RECVDSTOPTS:
1724                         case IPV6_RECVRTHDRDSTOPTS:
1725                                 if (td != NULL) {
1726                                         error = priv_check(td,
1727                                             PRIV_NETINET_SETHDROPTS);
1728                                         if (error)
1729                                                 break;
1730                                 }
1731                                 /* FALLTHROUGH */
1732                         case IPV6_UNICAST_HOPS:
1733                         case IPV6_HOPLIMIT:
1734
1735                         case IPV6_RECVPKTINFO:
1736                         case IPV6_RECVHOPLIMIT:
1737                         case IPV6_RECVRTHDR:
1738                         case IPV6_RECVPATHMTU:
1739                         case IPV6_RECVTCLASS:
1740                         case IPV6_RECVFLOWID:
1741 #ifdef  RSS
1742                         case IPV6_RECVRSSBUCKETID:
1743 #endif
1744                         case IPV6_V6ONLY:
1745                         case IPV6_AUTOFLOWLABEL:
1746                         case IPV6_ORIGDSTADDR:
1747                         case IPV6_BINDANY:
1748                         case IPV6_BINDMULTI:
1749 #ifdef  RSS
1750                         case IPV6_RSS_LISTEN_BUCKET:
1751 #endif
1752                         case IPV6_VLAN_PCP:
1753                                 if (optname == IPV6_BINDANY && td != NULL) {
1754                                         error = priv_check(td,
1755                                             PRIV_NETINET_BINDANY);
1756                                         if (error)
1757                                                 break;
1758                                 }
1759
1760                                 if (optlen != sizeof(int)) {
1761                                         error = EINVAL;
1762                                         break;
1763                                 }
1764                                 error = sooptcopyin(sopt, &optval,
1765                                         sizeof optval, sizeof optval);
1766                                 if (error)
1767                                         break;
1768                                 switch (optname) {
1769                                 case IPV6_UNICAST_HOPS:
1770                                         if (optval < -1 || optval >= 256)
1771                                                 error = EINVAL;
1772                                         else {
1773                                                 /* -1 = kernel default */
1774                                                 inp->in6p_hops = optval;
1775                                                 if ((inp->inp_vflag &
1776                                                      INP_IPV4) != 0)
1777                                                         inp->inp_ip_ttl = optval;
1778                                         }
1779                                         break;
1780 #define OPTSET(bit) \
1781 do { \
1782         INP_WLOCK(inp); \
1783         if (optval) \
1784                 inp->inp_flags |= (bit); \
1785         else \
1786                 inp->inp_flags &= ~(bit); \
1787         INP_WUNLOCK(inp); \
1788 } while (/*CONSTCOND*/ 0)
1789 #define OPTSET2292(bit) \
1790 do { \
1791         INP_WLOCK(inp); \
1792         inp->inp_flags |= IN6P_RFC2292; \
1793         if (optval) \
1794                 inp->inp_flags |= (bit); \
1795         else \
1796                 inp->inp_flags &= ~(bit); \
1797         INP_WUNLOCK(inp); \
1798 } while (/*CONSTCOND*/ 0)
1799 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1800
1801 #define OPTSET2_N(bit, val) do {                                        \
1802         if (val)                                                        \
1803                 inp->inp_flags2 |= bit;                                 \
1804         else                                                            \
1805                 inp->inp_flags2 &= ~bit;                                \
1806 } while (0)
1807 #define OPTSET2(bit, val) do {                                          \
1808         INP_WLOCK(inp);                                                 \
1809         OPTSET2_N(bit, val);                                            \
1810         INP_WUNLOCK(inp);                                               \
1811 } while (0)
1812 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1813 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1814 do {                                                                    \
1815         INP_WLOCK(inp);                                                 \
1816         if (OPTBIT(IN6P_RFC2292)) {                                     \
1817                 error = EINVAL;                                         \
1818         } else {                                                        \
1819                 if (optval)                                             \
1820                         inp->inp_flags |= (bit);                        \
1821                 else                                                    \
1822                         inp->inp_flags &= ~(bit);                       \
1823         }                                                               \
1824         INP_WUNLOCK(inp);                                               \
1825 } while (/*CONSTCOND*/ 0)
1826
1827                                 case IPV6_RECVPKTINFO:
1828                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1829                                         break;
1830
1831                                 case IPV6_HOPLIMIT:
1832                                 {
1833                                         struct ip6_pktopts **optp;
1834
1835                                         /* cannot mix with RFC2292 */
1836                                         if (OPTBIT(IN6P_RFC2292)) {
1837                                                 error = EINVAL;
1838                                                 break;
1839                                         }
1840                                         INP_WLOCK(inp);
1841                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1842                                                 INP_WUNLOCK(inp);
1843                                                 return (ECONNRESET);
1844                                         }
1845                                         optp = &inp->in6p_outputopts;
1846                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1847                                             (u_char *)&optval, sizeof(optval),
1848                                             optp, (td != NULL) ? td->td_ucred :
1849                                             NULL, uproto);
1850                                         INP_WUNLOCK(inp);
1851                                         break;
1852                                 }
1853
1854                                 case IPV6_RECVHOPLIMIT:
1855                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1856                                         break;
1857
1858                                 case IPV6_RECVHOPOPTS:
1859                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1860                                         break;
1861
1862                                 case IPV6_RECVDSTOPTS:
1863                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1864                                         break;
1865
1866                                 case IPV6_RECVRTHDRDSTOPTS:
1867                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1868                                         break;
1869
1870                                 case IPV6_RECVRTHDR:
1871                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1872                                         break;
1873
1874                                 case IPV6_RECVPATHMTU:
1875                                         /*
1876                                          * We ignore this option for TCP
1877                                          * sockets.
1878                                          * (RFC3542 leaves this case
1879                                          * unspecified.)
1880                                          */
1881                                         if (uproto != IPPROTO_TCP)
1882                                                 OPTSET(IN6P_MTU);
1883                                         break;
1884
1885                                 case IPV6_RECVFLOWID:
1886                                         OPTSET2(INP_RECVFLOWID, optval);
1887                                         break;
1888
1889 #ifdef  RSS
1890                                 case IPV6_RECVRSSBUCKETID:
1891                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1892                                         break;
1893 #endif
1894
1895                                 case IPV6_V6ONLY:
1896                                         INP_WLOCK(inp);
1897                                         if (inp->inp_lport ||
1898                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1899                                                 /*
1900                                                  * The socket is already bound.
1901                                                  */
1902                                                 INP_WUNLOCK(inp);
1903                                                 error = EINVAL;
1904                                                 break;
1905                                         }
1906                                         if (optval) {
1907                                                 inp->inp_flags |= IN6P_IPV6_V6ONLY;
1908                                                 inp->inp_vflag &= ~INP_IPV4;
1909                                         } else {
1910                                                 inp->inp_flags &= ~IN6P_IPV6_V6ONLY;
1911                                                 inp->inp_vflag |= INP_IPV4;
1912                                         }
1913                                         INP_WUNLOCK(inp);
1914                                         break;
1915                                 case IPV6_RECVTCLASS:
1916                                         /* cannot mix with RFC2292 XXX */
1917                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1918                                         break;
1919                                 case IPV6_AUTOFLOWLABEL:
1920                                         OPTSET(IN6P_AUTOFLOWLABEL);
1921                                         break;
1922
1923                                 case IPV6_ORIGDSTADDR:
1924                                         OPTSET2(INP_ORIGDSTADDR, optval);
1925                                         break;
1926                                 case IPV6_BINDANY:
1927                                         OPTSET(INP_BINDANY);
1928                                         break;
1929
1930                                 case IPV6_BINDMULTI:
1931                                         OPTSET2(INP_BINDMULTI, optval);
1932                                         break;
1933 #ifdef  RSS
1934                                 case IPV6_RSS_LISTEN_BUCKET:
1935                                         if ((optval >= 0) &&
1936                                             (optval < rss_getnumbuckets())) {
1937                                                 INP_WLOCK(inp);
1938                                                 inp->inp_rss_listen_bucket = optval;
1939                                                 OPTSET2_N(INP_RSS_BUCKET_SET, 1);
1940                                                 INP_WUNLOCK(inp);
1941                                         } else {
1942                                                 error = EINVAL;
1943                                         }
1944                                         break;
1945 #endif
1946                                 case IPV6_VLAN_PCP:
1947                                         if ((optval >= -1) && (optval <=
1948                                             (INP_2PCP_MASK >> INP_2PCP_SHIFT))) {
1949                                                 if (optval == -1) {
1950                                                         INP_WLOCK(inp);
1951                                                         inp->inp_flags2 &=
1952                                                             ~(INP_2PCP_SET |
1953                                                             INP_2PCP_MASK);
1954                                                         INP_WUNLOCK(inp);
1955                                                 } else {
1956                                                         INP_WLOCK(inp);
1957                                                         inp->inp_flags2 |=
1958                                                             INP_2PCP_SET;
1959                                                         inp->inp_flags2 &=
1960                                                             ~INP_2PCP_MASK;
1961                                                         inp->inp_flags2 |=
1962                                                             optval <<
1963                                                             INP_2PCP_SHIFT;
1964                                                         INP_WUNLOCK(inp);
1965                                                 }
1966                                         } else
1967                                                 error = EINVAL;
1968                                         break;
1969                                 }
1970                                 break;
1971
1972                         case IPV6_TCLASS:
1973                         case IPV6_DONTFRAG:
1974                         case IPV6_USE_MIN_MTU:
1975                         case IPV6_PREFER_TEMPADDR:
1976                                 if (optlen != sizeof(optval)) {
1977                                         error = EINVAL;
1978                                         break;
1979                                 }
1980                                 error = sooptcopyin(sopt, &optval,
1981                                         sizeof optval, sizeof optval);
1982                                 if (error)
1983                                         break;
1984                                 {
1985                                         struct ip6_pktopts **optp;
1986                                         INP_WLOCK(inp);
1987                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1988                                                 INP_WUNLOCK(inp);
1989                                                 return (ECONNRESET);
1990                                         }
1991                                         optp = &inp->in6p_outputopts;
1992                                         error = ip6_pcbopt(optname,
1993                                             (u_char *)&optval, sizeof(optval),
1994                                             optp, (td != NULL) ? td->td_ucred :
1995                                             NULL, uproto);
1996                                         INP_WUNLOCK(inp);
1997                                         break;
1998                                 }
1999
2000                         case IPV6_2292PKTINFO:
2001                         case IPV6_2292HOPLIMIT:
2002                         case IPV6_2292HOPOPTS:
2003                         case IPV6_2292DSTOPTS:
2004                         case IPV6_2292RTHDR:
2005                                 /* RFC 2292 */
2006                                 if (optlen != sizeof(int)) {
2007                                         error = EINVAL;
2008                                         break;
2009                                 }
2010                                 error = sooptcopyin(sopt, &optval,
2011                                         sizeof optval, sizeof optval);
2012                                 if (error)
2013                                         break;
2014                                 switch (optname) {
2015                                 case IPV6_2292PKTINFO:
2016                                         OPTSET2292(IN6P_PKTINFO);
2017                                         break;
2018                                 case IPV6_2292HOPLIMIT:
2019                                         OPTSET2292(IN6P_HOPLIMIT);
2020                                         break;
2021                                 case IPV6_2292HOPOPTS:
2022                                         /*
2023                                          * Check super-user privilege.
2024                                          * See comments for IPV6_RECVHOPOPTS.
2025                                          */
2026                                         if (td != NULL) {
2027                                                 error = priv_check(td,
2028                                                     PRIV_NETINET_SETHDROPTS);
2029                                                 if (error)
2030                                                         return (error);
2031                                         }
2032                                         OPTSET2292(IN6P_HOPOPTS);
2033                                         break;
2034                                 case IPV6_2292DSTOPTS:
2035                                         if (td != NULL) {
2036                                                 error = priv_check(td,
2037                                                     PRIV_NETINET_SETHDROPTS);
2038                                                 if (error)
2039                                                         return (error);
2040                                         }
2041                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
2042                                         break;
2043                                 case IPV6_2292RTHDR:
2044                                         OPTSET2292(IN6P_RTHDR);
2045                                         break;
2046                                 }
2047                                 break;
2048                         case IPV6_PKTINFO:
2049                         case IPV6_HOPOPTS:
2050                         case IPV6_RTHDR:
2051                         case IPV6_DSTOPTS:
2052                         case IPV6_RTHDRDSTOPTS:
2053                         case IPV6_NEXTHOP:
2054                         {
2055                                 /* new advanced API (RFC3542) */
2056                                 u_char *optbuf;
2057                                 u_char optbuf_storage[MCLBYTES];
2058                                 int optlen;
2059                                 struct ip6_pktopts **optp;
2060
2061                                 /* cannot mix with RFC2292 */
2062                                 if (OPTBIT(IN6P_RFC2292)) {
2063                                         error = EINVAL;
2064                                         break;
2065                                 }
2066
2067                                 /*
2068                                  * We only ensure valsize is not too large
2069                                  * here.  Further validation will be done
2070                                  * later.
2071                                  */
2072                                 error = sooptcopyin(sopt, optbuf_storage,
2073                                     sizeof(optbuf_storage), 0);
2074                                 if (error)
2075                                         break;
2076                                 optlen = sopt->sopt_valsize;
2077                                 optbuf = optbuf_storage;
2078                                 INP_WLOCK(inp);
2079                                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
2080                                         INP_WUNLOCK(inp);
2081                                         return (ECONNRESET);
2082                                 }
2083                                 optp = &inp->in6p_outputopts;
2084                                 error = ip6_pcbopt(optname, optbuf, optlen,
2085                                     optp, (td != NULL) ? td->td_ucred : NULL,
2086                                     uproto);
2087                                 INP_WUNLOCK(inp);
2088                                 break;
2089                         }
2090 #undef OPTSET
2091
2092                         case IPV6_MULTICAST_IF:
2093                         case IPV6_MULTICAST_HOPS:
2094                         case IPV6_MULTICAST_LOOP:
2095                         case IPV6_JOIN_GROUP:
2096                         case IPV6_LEAVE_GROUP:
2097                         case IPV6_MSFILTER:
2098                         case MCAST_BLOCK_SOURCE:
2099                         case MCAST_UNBLOCK_SOURCE:
2100                         case MCAST_JOIN_GROUP:
2101                         case MCAST_LEAVE_GROUP:
2102                         case MCAST_JOIN_SOURCE_GROUP:
2103                         case MCAST_LEAVE_SOURCE_GROUP:
2104                                 error = ip6_setmoptions(inp, sopt);
2105                                 break;
2106
2107                         case IPV6_PORTRANGE:
2108                                 error = sooptcopyin(sopt, &optval,
2109                                     sizeof optval, sizeof optval);
2110                                 if (error)
2111                                         break;
2112
2113                                 INP_WLOCK(inp);
2114                                 switch (optval) {
2115                                 case IPV6_PORTRANGE_DEFAULT:
2116                                         inp->inp_flags &= ~(INP_LOWPORT);
2117                                         inp->inp_flags &= ~(INP_HIGHPORT);
2118                                         break;
2119
2120                                 case IPV6_PORTRANGE_HIGH:
2121                                         inp->inp_flags &= ~(INP_LOWPORT);
2122                                         inp->inp_flags |= INP_HIGHPORT;
2123                                         break;
2124
2125                                 case IPV6_PORTRANGE_LOW:
2126                                         inp->inp_flags &= ~(INP_HIGHPORT);
2127                                         inp->inp_flags |= INP_LOWPORT;
2128                                         break;
2129
2130                                 default:
2131                                         error = EINVAL;
2132                                         break;
2133                                 }
2134                                 INP_WUNLOCK(inp);
2135                                 break;
2136
2137 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2138                         case IPV6_IPSEC_POLICY:
2139                                 if (IPSEC_ENABLED(ipv6)) {
2140                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2141                                         break;
2142                                 }
2143                                 /* FALLTHROUGH */
2144 #endif /* IPSEC */
2145
2146                         default:
2147                                 error = ENOPROTOOPT;
2148                                 break;
2149                         }
2150                         break;
2151
2152                 case SOPT_GET:
2153                         switch (optname) {
2154                         case IPV6_2292PKTOPTIONS:
2155 #ifdef IPV6_PKTOPTIONS
2156                         case IPV6_PKTOPTIONS:
2157 #endif
2158                                 /*
2159                                  * RFC3542 (effectively) deprecated the
2160                                  * semantics of the 2292-style pktoptions.
2161                                  * Since it was not reliable in nature (i.e.,
2162                                  * applications had to expect the lack of some
2163                                  * information after all), it would make sense
2164                                  * to simplify this part by always returning
2165                                  * empty data.
2166                                  */
2167                                 sopt->sopt_valsize = 0;
2168                                 break;
2169
2170                         case IPV6_RECVHOPOPTS:
2171                         case IPV6_RECVDSTOPTS:
2172                         case IPV6_RECVRTHDRDSTOPTS:
2173                         case IPV6_UNICAST_HOPS:
2174                         case IPV6_RECVPKTINFO:
2175                         case IPV6_RECVHOPLIMIT:
2176                         case IPV6_RECVRTHDR:
2177                         case IPV6_RECVPATHMTU:
2178
2179                         case IPV6_V6ONLY:
2180                         case IPV6_PORTRANGE:
2181                         case IPV6_RECVTCLASS:
2182                         case IPV6_AUTOFLOWLABEL:
2183                         case IPV6_BINDANY:
2184                         case IPV6_FLOWID:
2185                         case IPV6_FLOWTYPE:
2186                         case IPV6_RECVFLOWID:
2187 #ifdef  RSS
2188                         case IPV6_RSSBUCKETID:
2189                         case IPV6_RECVRSSBUCKETID:
2190 #endif
2191                         case IPV6_BINDMULTI:
2192                         case IPV6_VLAN_PCP:
2193                                 switch (optname) {
2194                                 case IPV6_RECVHOPOPTS:
2195                                         optval = OPTBIT(IN6P_HOPOPTS);
2196                                         break;
2197
2198                                 case IPV6_RECVDSTOPTS:
2199                                         optval = OPTBIT(IN6P_DSTOPTS);
2200                                         break;
2201
2202                                 case IPV6_RECVRTHDRDSTOPTS:
2203                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2204                                         break;
2205
2206                                 case IPV6_UNICAST_HOPS:
2207                                         optval = inp->in6p_hops;
2208                                         break;
2209
2210                                 case IPV6_RECVPKTINFO:
2211                                         optval = OPTBIT(IN6P_PKTINFO);
2212                                         break;
2213
2214                                 case IPV6_RECVHOPLIMIT:
2215                                         optval = OPTBIT(IN6P_HOPLIMIT);
2216                                         break;
2217
2218                                 case IPV6_RECVRTHDR:
2219                                         optval = OPTBIT(IN6P_RTHDR);
2220                                         break;
2221
2222                                 case IPV6_RECVPATHMTU:
2223                                         optval = OPTBIT(IN6P_MTU);
2224                                         break;
2225
2226                                 case IPV6_V6ONLY:
2227                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2228                                         break;
2229
2230                                 case IPV6_PORTRANGE:
2231                                     {
2232                                         int flags;
2233                                         flags = inp->inp_flags;
2234                                         if (flags & INP_HIGHPORT)
2235                                                 optval = IPV6_PORTRANGE_HIGH;
2236                                         else if (flags & INP_LOWPORT)
2237                                                 optval = IPV6_PORTRANGE_LOW;
2238                                         else
2239                                                 optval = 0;
2240                                         break;
2241                                     }
2242                                 case IPV6_RECVTCLASS:
2243                                         optval = OPTBIT(IN6P_TCLASS);
2244                                         break;
2245
2246                                 case IPV6_AUTOFLOWLABEL:
2247                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2248                                         break;
2249
2250                                 case IPV6_ORIGDSTADDR:
2251                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2252                                         break;
2253
2254                                 case IPV6_BINDANY:
2255                                         optval = OPTBIT(INP_BINDANY);
2256                                         break;
2257
2258                                 case IPV6_FLOWID:
2259                                         optval = inp->inp_flowid;
2260                                         break;
2261
2262                                 case IPV6_FLOWTYPE:
2263                                         optval = inp->inp_flowtype;
2264                                         break;
2265
2266                                 case IPV6_RECVFLOWID:
2267                                         optval = OPTBIT2(INP_RECVFLOWID);
2268                                         break;
2269 #ifdef  RSS
2270                                 case IPV6_RSSBUCKETID:
2271                                         retval =
2272                                             rss_hash2bucket(inp->inp_flowid,
2273                                             inp->inp_flowtype,
2274                                             &rss_bucket);
2275                                         if (retval == 0)
2276                                                 optval = rss_bucket;
2277                                         else
2278                                                 error = EINVAL;
2279                                         break;
2280
2281                                 case IPV6_RECVRSSBUCKETID:
2282                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2283                                         break;
2284 #endif
2285
2286                                 case IPV6_BINDMULTI:
2287                                         optval = OPTBIT2(INP_BINDMULTI);
2288                                         break;
2289
2290                                 case IPV6_VLAN_PCP:
2291                                         if (OPTBIT2(INP_2PCP_SET)) {
2292                                                 optval = (inp->inp_flags2 &
2293                                                             INP_2PCP_MASK) >>
2294                                                             INP_2PCP_SHIFT;
2295                                         } else {
2296                                                 optval = -1;
2297                                         }
2298                                         break;
2299                                 }
2300
2301                                 if (error)
2302                                         break;
2303                                 error = sooptcopyout(sopt, &optval,
2304                                         sizeof optval);
2305                                 break;
2306
2307                         case IPV6_PATHMTU:
2308                         {
2309                                 u_long pmtu = 0;
2310                                 struct ip6_mtuinfo mtuinfo;
2311                                 struct in6_addr addr;
2312
2313                                 if (!(so->so_state & SS_ISCONNECTED))
2314                                         return (ENOTCONN);
2315                                 /*
2316                                  * XXX: we dot not consider the case of source
2317                                  * routing, or optional information to specify
2318                                  * the outgoing interface.
2319                                  * Copy faddr out of inp to avoid holding lock
2320                                  * on inp during route lookup.
2321                                  */
2322                                 INP_RLOCK(inp);
2323                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2324                                 INP_RUNLOCK(inp);
2325                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2326                                     &addr, &pmtu);
2327                                 if (error)
2328                                         break;
2329                                 if (pmtu > IPV6_MAXPACKET)
2330                                         pmtu = IPV6_MAXPACKET;
2331
2332                                 bzero(&mtuinfo, sizeof(mtuinfo));
2333                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2334                                 optdata = (void *)&mtuinfo;
2335                                 optdatalen = sizeof(mtuinfo);
2336                                 error = sooptcopyout(sopt, optdata,
2337                                     optdatalen);
2338                                 break;
2339                         }
2340
2341                         case IPV6_2292PKTINFO:
2342                         case IPV6_2292HOPLIMIT:
2343                         case IPV6_2292HOPOPTS:
2344                         case IPV6_2292RTHDR:
2345                         case IPV6_2292DSTOPTS:
2346                                 switch (optname) {
2347                                 case IPV6_2292PKTINFO:
2348                                         optval = OPTBIT(IN6P_PKTINFO);
2349                                         break;
2350                                 case IPV6_2292HOPLIMIT:
2351                                         optval = OPTBIT(IN6P_HOPLIMIT);
2352                                         break;
2353                                 case IPV6_2292HOPOPTS:
2354                                         optval = OPTBIT(IN6P_HOPOPTS);
2355                                         break;
2356                                 case IPV6_2292RTHDR:
2357                                         optval = OPTBIT(IN6P_RTHDR);
2358                                         break;
2359                                 case IPV6_2292DSTOPTS:
2360                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2361                                         break;
2362                                 }
2363                                 error = sooptcopyout(sopt, &optval,
2364                                     sizeof optval);
2365                                 break;
2366                         case IPV6_PKTINFO:
2367                         case IPV6_HOPOPTS:
2368                         case IPV6_RTHDR:
2369                         case IPV6_DSTOPTS:
2370                         case IPV6_RTHDRDSTOPTS:
2371                         case IPV6_NEXTHOP:
2372                         case IPV6_TCLASS:
2373                         case IPV6_DONTFRAG:
2374                         case IPV6_USE_MIN_MTU:
2375                         case IPV6_PREFER_TEMPADDR:
2376                                 error = ip6_getpcbopt(inp, optname, sopt);
2377                                 break;
2378
2379                         case IPV6_MULTICAST_IF:
2380                         case IPV6_MULTICAST_HOPS:
2381                         case IPV6_MULTICAST_LOOP:
2382                         case IPV6_MSFILTER:
2383                                 error = ip6_getmoptions(inp, sopt);
2384                                 break;
2385
2386 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2387                         case IPV6_IPSEC_POLICY:
2388                                 if (IPSEC_ENABLED(ipv6)) {
2389                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2390                                         break;
2391                                 }
2392                                 /* FALLTHROUGH */
2393 #endif /* IPSEC */
2394                         default:
2395                                 error = ENOPROTOOPT;
2396                                 break;
2397                         }
2398                         break;
2399                 }
2400         }
2401         return (error);
2402 }
2403
2404 int
2405 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2406 {
2407         int error = 0, optval, optlen;
2408         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2409         struct inpcb *inp = sotoinpcb(so);
2410         int level, op, optname;
2411
2412         level = sopt->sopt_level;
2413         op = sopt->sopt_dir;
2414         optname = sopt->sopt_name;
2415         optlen = sopt->sopt_valsize;
2416
2417         if (level != IPPROTO_IPV6) {
2418                 return (EINVAL);
2419         }
2420
2421         switch (optname) {
2422         case IPV6_CHECKSUM:
2423                 /*
2424                  * For ICMPv6 sockets, no modification allowed for checksum
2425                  * offset, permit "no change" values to help existing apps.
2426                  *
2427                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2428                  * for an ICMPv6 socket will fail."
2429                  * The current behavior does not meet RFC3542.
2430                  */
2431                 switch (op) {
2432                 case SOPT_SET:
2433                         if (optlen != sizeof(int)) {
2434                                 error = EINVAL;
2435                                 break;
2436                         }
2437                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2438                                             sizeof(optval));
2439                         if (error)
2440                                 break;
2441                         if (optval < -1 || (optval % 2) != 0) {
2442                                 /*
2443                                  * The API assumes non-negative even offset
2444                                  * values or -1 as a special value.
2445                                  */
2446                                 error = EINVAL;
2447                         } else if (so->so_proto->pr_protocol ==
2448                             IPPROTO_ICMPV6) {
2449                                 if (optval != icmp6off)
2450                                         error = EINVAL;
2451                         } else
2452                                 inp->in6p_cksum = optval;
2453                         break;
2454
2455                 case SOPT_GET:
2456                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2457                                 optval = icmp6off;
2458                         else
2459                                 optval = inp->in6p_cksum;
2460
2461                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2462                         break;
2463
2464                 default:
2465                         error = EINVAL;
2466                         break;
2467                 }
2468                 break;
2469
2470         default:
2471                 error = ENOPROTOOPT;
2472                 break;
2473         }
2474
2475         return (error);
2476 }
2477
2478 /*
2479  * Set up IP6 options in pcb for insertion in output packets or
2480  * specifying behavior of outgoing packets.
2481  */
2482 static int
2483 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2484     struct socket *so, struct sockopt *sopt)
2485 {
2486         struct ip6_pktopts *opt = *pktopt;
2487         int error = 0;
2488         struct thread *td = sopt->sopt_td;
2489         struct epoch_tracker et;
2490
2491         /* turn off any old options. */
2492         if (opt) {
2493 #ifdef DIAGNOSTIC
2494                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2495                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2496                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2497                         printf("ip6_pcbopts: all specified options are cleared.\n");
2498 #endif
2499                 ip6_clearpktopts(opt, -1);
2500         } else {
2501                 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT);
2502                 if (opt == NULL)
2503                         return (ENOMEM);
2504         }
2505         *pktopt = NULL;
2506
2507         if (!m || m->m_len == 0) {
2508                 /*
2509                  * Only turning off any previous options, regardless of
2510                  * whether the opt is just created or given.
2511                  */
2512                 free(opt, M_IP6OPT);
2513                 return (0);
2514         }
2515
2516         /*  set options specified by user. */
2517         NET_EPOCH_ENTER(et);
2518         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2519             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2520                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2521                 free(opt, M_IP6OPT);
2522                 NET_EPOCH_EXIT(et);
2523                 return (error);
2524         }
2525         NET_EPOCH_EXIT(et);
2526         *pktopt = opt;
2527         return (0);
2528 }
2529
2530 /*
2531  * initialize ip6_pktopts.  beware that there are non-zero default values in
2532  * the struct.
2533  */
2534 void
2535 ip6_initpktopts(struct ip6_pktopts *opt)
2536 {
2537
2538         bzero(opt, sizeof(*opt));
2539         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2540         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2541         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2542         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2543 }
2544
2545 static int
2546 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2547     struct ucred *cred, int uproto)
2548 {
2549         struct epoch_tracker et;
2550         struct ip6_pktopts *opt;
2551         int ret;
2552
2553         if (*pktopt == NULL) {
2554                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2555                     M_NOWAIT);
2556                 if (*pktopt == NULL)
2557                         return (ENOBUFS);
2558                 ip6_initpktopts(*pktopt);
2559         }
2560         opt = *pktopt;
2561
2562         NET_EPOCH_ENTER(et);
2563         ret = ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto);
2564         NET_EPOCH_EXIT(et);
2565
2566         return (ret);
2567 }
2568
2569 #define GET_PKTOPT_VAR(field, lenexpr) do {                                     \
2570         if (pktopt && pktopt->field) {                                          \
2571                 INP_RUNLOCK(inp);                                               \
2572                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK);         \
2573                 malloc_optdata = true;                                          \
2574                 INP_RLOCK(inp);                                                 \
2575                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {            \
2576                         INP_RUNLOCK(inp);                                       \
2577                         free(optdata, M_TEMP);                                  \
2578                         return (ECONNRESET);                                    \
2579                 }                                                               \
2580                 pktopt = inp->in6p_outputopts;                                  \
2581                 if (pktopt && pktopt->field) {                                  \
2582                         optdatalen = min(lenexpr, sopt->sopt_valsize);          \
2583                         bcopy(pktopt->field, optdata, optdatalen);              \
2584                 } else {                                                        \
2585                         free(optdata, M_TEMP);                                  \
2586                         optdata = NULL;                                         \
2587                         malloc_optdata = false;                                 \
2588                 }                                                               \
2589         }                                                                       \
2590 } while(0)
2591
2592 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                         \
2593         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2594
2595 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                        \
2596         pktopt->field->sa_len)
2597
2598 static int
2599 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2600 {
2601         void *optdata = NULL;
2602         bool malloc_optdata = false;
2603         int optdatalen = 0;
2604         int error = 0;
2605         struct in6_pktinfo null_pktinfo;
2606         int deftclass = 0, on;
2607         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2608         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2609         struct ip6_pktopts *pktopt;
2610
2611         INP_RLOCK(inp);
2612         pktopt = inp->in6p_outputopts;
2613
2614         switch (optname) {
2615         case IPV6_PKTINFO:
2616                 optdata = (void *)&null_pktinfo;
2617                 if (pktopt && pktopt->ip6po_pktinfo) {
2618                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2619                             sizeof(null_pktinfo));
2620                         in6_clearscope(&null_pktinfo.ipi6_addr);
2621                 } else {
2622                         /* XXX: we don't have to do this every time... */
2623                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2624                 }
2625                 optdatalen = sizeof(struct in6_pktinfo);
2626                 break;
2627         case IPV6_TCLASS:
2628                 if (pktopt && pktopt->ip6po_tclass >= 0)
2629                         deftclass = pktopt->ip6po_tclass;
2630                 optdata = (void *)&deftclass;
2631                 optdatalen = sizeof(int);
2632                 break;
2633         case IPV6_HOPOPTS:
2634                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2635                 break;
2636         case IPV6_RTHDR:
2637                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2638                 break;
2639         case IPV6_RTHDRDSTOPTS:
2640                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2641                 break;
2642         case IPV6_DSTOPTS:
2643                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2644                 break;
2645         case IPV6_NEXTHOP:
2646                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2647                 break;
2648         case IPV6_USE_MIN_MTU:
2649                 if (pktopt)
2650                         defminmtu = pktopt->ip6po_minmtu;
2651                 optdata = (void *)&defminmtu;
2652                 optdatalen = sizeof(int);
2653                 break;
2654         case IPV6_DONTFRAG:
2655                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2656                         on = 1;
2657                 else
2658                         on = 0;
2659                 optdata = (void *)&on;
2660                 optdatalen = sizeof(on);
2661                 break;
2662         case IPV6_PREFER_TEMPADDR:
2663                 if (pktopt)
2664                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2665                 optdata = (void *)&defpreftemp;
2666                 optdatalen = sizeof(int);
2667                 break;
2668         default:                /* should not happen */
2669 #ifdef DIAGNOSTIC
2670                 panic("ip6_getpcbopt: unexpected option\n");
2671 #endif
2672                 INP_RUNLOCK(inp);
2673                 return (ENOPROTOOPT);
2674         }
2675         INP_RUNLOCK(inp);
2676
2677         error = sooptcopyout(sopt, optdata, optdatalen);
2678         if (malloc_optdata)
2679                 free(optdata, M_TEMP);
2680
2681         return (error);
2682 }
2683
2684 void
2685 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2686 {
2687         if (pktopt == NULL)
2688                 return;
2689
2690         if (optname == -1 || optname == IPV6_PKTINFO) {
2691                 if (pktopt->ip6po_pktinfo)
2692                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2693                 pktopt->ip6po_pktinfo = NULL;
2694         }
2695         if (optname == -1 || optname == IPV6_HOPLIMIT)
2696                 pktopt->ip6po_hlim = -1;
2697         if (optname == -1 || optname == IPV6_TCLASS)
2698                 pktopt->ip6po_tclass = -1;
2699         if (optname == -1 || optname == IPV6_NEXTHOP) {
2700                 if (pktopt->ip6po_nextroute.ro_nh) {
2701                         NH_FREE(pktopt->ip6po_nextroute.ro_nh);
2702                         pktopt->ip6po_nextroute.ro_nh = NULL;
2703                 }
2704                 if (pktopt->ip6po_nexthop)
2705                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2706                 pktopt->ip6po_nexthop = NULL;
2707         }
2708         if (optname == -1 || optname == IPV6_HOPOPTS) {
2709                 if (pktopt->ip6po_hbh)
2710                         free(pktopt->ip6po_hbh, M_IP6OPT);
2711                 pktopt->ip6po_hbh = NULL;
2712         }
2713         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2714                 if (pktopt->ip6po_dest1)
2715                         free(pktopt->ip6po_dest1, M_IP6OPT);
2716                 pktopt->ip6po_dest1 = NULL;
2717         }
2718         if (optname == -1 || optname == IPV6_RTHDR) {
2719                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2720                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2721                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2722                 if (pktopt->ip6po_route.ro_nh) {
2723                         NH_FREE(pktopt->ip6po_route.ro_nh);
2724                         pktopt->ip6po_route.ro_nh = NULL;
2725                 }
2726         }
2727         if (optname == -1 || optname == IPV6_DSTOPTS) {
2728                 if (pktopt->ip6po_dest2)
2729                         free(pktopt->ip6po_dest2, M_IP6OPT);
2730                 pktopt->ip6po_dest2 = NULL;
2731         }
2732 }
2733
2734 #define PKTOPT_EXTHDRCPY(type) \
2735 do {\
2736         if (src->type) {\
2737                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2738                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2739                 if (dst->type == NULL)\
2740                         goto bad;\
2741                 bcopy(src->type, dst->type, hlen);\
2742         }\
2743 } while (/*CONSTCOND*/ 0)
2744
2745 static int
2746 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2747 {
2748         if (dst == NULL || src == NULL)  {
2749                 printf("ip6_clearpktopts: invalid argument\n");
2750                 return (EINVAL);
2751         }
2752
2753         dst->ip6po_hlim = src->ip6po_hlim;
2754         dst->ip6po_tclass = src->ip6po_tclass;
2755         dst->ip6po_flags = src->ip6po_flags;
2756         dst->ip6po_minmtu = src->ip6po_minmtu;
2757         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2758         if (src->ip6po_pktinfo) {
2759                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2760                     M_IP6OPT, canwait);
2761                 if (dst->ip6po_pktinfo == NULL)
2762                         goto bad;
2763                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2764         }
2765         if (src->ip6po_nexthop) {
2766                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2767                     M_IP6OPT, canwait);
2768                 if (dst->ip6po_nexthop == NULL)
2769                         goto bad;
2770                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2771                     src->ip6po_nexthop->sa_len);
2772         }
2773         PKTOPT_EXTHDRCPY(ip6po_hbh);
2774         PKTOPT_EXTHDRCPY(ip6po_dest1);
2775         PKTOPT_EXTHDRCPY(ip6po_dest2);
2776         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2777         return (0);
2778
2779   bad:
2780         ip6_clearpktopts(dst, -1);
2781         return (ENOBUFS);
2782 }
2783 #undef PKTOPT_EXTHDRCPY
2784
2785 struct ip6_pktopts *
2786 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2787 {
2788         int error;
2789         struct ip6_pktopts *dst;
2790
2791         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2792         if (dst == NULL)
2793                 return (NULL);
2794         ip6_initpktopts(dst);
2795
2796         if ((error = copypktopts(dst, src, canwait)) != 0) {
2797                 free(dst, M_IP6OPT);
2798                 return (NULL);
2799         }
2800
2801         return (dst);
2802 }
2803
2804 void
2805 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2806 {
2807         if (pktopt == NULL)
2808                 return;
2809
2810         ip6_clearpktopts(pktopt, -1);
2811
2812         free(pktopt, M_IP6OPT);
2813 }
2814
2815 /*
2816  * Set IPv6 outgoing packet options based on advanced API.
2817  */
2818 int
2819 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2820     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2821 {
2822         struct cmsghdr *cm = NULL;
2823
2824         if (control == NULL || opt == NULL)
2825                 return (EINVAL);
2826
2827         /*
2828          * ip6_setpktopt can call ifnet_byindex(), so it's imperative that we
2829          * are in the network epoch here.
2830          */
2831         NET_EPOCH_ASSERT();
2832
2833         ip6_initpktopts(opt);
2834         if (stickyopt) {
2835                 int error;
2836
2837                 /*
2838                  * If stickyopt is provided, make a local copy of the options
2839                  * for this particular packet, then override them by ancillary
2840                  * objects.
2841                  * XXX: copypktopts() does not copy the cached route to a next
2842                  * hop (if any).  This is not very good in terms of efficiency,
2843                  * but we can allow this since this option should be rarely
2844                  * used.
2845                  */
2846                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2847                         return (error);
2848         }
2849
2850         /*
2851          * XXX: Currently, we assume all the optional information is stored
2852          * in a single mbuf.
2853          */
2854         if (control->m_next)
2855                 return (EINVAL);
2856
2857         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2858             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2859                 int error;
2860
2861                 if (control->m_len < CMSG_LEN(0))
2862                         return (EINVAL);
2863
2864                 cm = mtod(control, struct cmsghdr *);
2865                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2866                         return (EINVAL);
2867                 if (cm->cmsg_level != IPPROTO_IPV6)
2868                         continue;
2869
2870                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2871                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2872                 if (error)
2873                         return (error);
2874         }
2875
2876         return (0);
2877 }
2878
2879 /*
2880  * Set a particular packet option, as a sticky option or an ancillary data
2881  * item.  "len" can be 0 only when it's a sticky option.
2882  * We have 4 cases of combination of "sticky" and "cmsg":
2883  * "sticky=0, cmsg=0": impossible
2884  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2885  * "sticky=1, cmsg=0": RFC3542 socket option
2886  * "sticky=1, cmsg=1": RFC2292 socket option
2887  */
2888 static int
2889 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2890     struct ucred *cred, int sticky, int cmsg, int uproto)
2891 {
2892         int minmtupolicy, preftemp;
2893         int error;
2894
2895         NET_EPOCH_ASSERT();
2896
2897         if (!sticky && !cmsg) {
2898 #ifdef DIAGNOSTIC
2899                 printf("ip6_setpktopt: impossible case\n");
2900 #endif
2901                 return (EINVAL);
2902         }
2903
2904         /*
2905          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2906          * not be specified in the context of RFC3542.  Conversely,
2907          * RFC3542 types should not be specified in the context of RFC2292.
2908          */
2909         if (!cmsg) {
2910                 switch (optname) {
2911                 case IPV6_2292PKTINFO:
2912                 case IPV6_2292HOPLIMIT:
2913                 case IPV6_2292NEXTHOP:
2914                 case IPV6_2292HOPOPTS:
2915                 case IPV6_2292DSTOPTS:
2916                 case IPV6_2292RTHDR:
2917                 case IPV6_2292PKTOPTIONS:
2918                         return (ENOPROTOOPT);
2919                 }
2920         }
2921         if (sticky && cmsg) {
2922                 switch (optname) {
2923                 case IPV6_PKTINFO:
2924                 case IPV6_HOPLIMIT:
2925                 case IPV6_NEXTHOP:
2926                 case IPV6_HOPOPTS:
2927                 case IPV6_DSTOPTS:
2928                 case IPV6_RTHDRDSTOPTS:
2929                 case IPV6_RTHDR:
2930                 case IPV6_USE_MIN_MTU:
2931                 case IPV6_DONTFRAG:
2932                 case IPV6_TCLASS:
2933                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2934                         return (ENOPROTOOPT);
2935                 }
2936         }
2937
2938         switch (optname) {
2939         case IPV6_2292PKTINFO:
2940         case IPV6_PKTINFO:
2941         {
2942                 struct ifnet *ifp = NULL;
2943                 struct in6_pktinfo *pktinfo;
2944
2945                 if (len != sizeof(struct in6_pktinfo))
2946                         return (EINVAL);
2947
2948                 pktinfo = (struct in6_pktinfo *)buf;
2949
2950                 /*
2951                  * An application can clear any sticky IPV6_PKTINFO option by
2952                  * doing a "regular" setsockopt with ipi6_addr being
2953                  * in6addr_any and ipi6_ifindex being zero.
2954                  * [RFC 3542, Section 6]
2955                  */
2956                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2957                     pktinfo->ipi6_ifindex == 0 &&
2958                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2959                         ip6_clearpktopts(opt, optname);
2960                         break;
2961                 }
2962
2963                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2964                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2965                         return (EINVAL);
2966                 }
2967                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2968                         return (EINVAL);
2969                 /* validate the interface index if specified. */
2970                 if (pktinfo->ipi6_ifindex) {
2971                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2972                         if (ifp == NULL)
2973                                 return (ENXIO);
2974                 }
2975                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2976                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2977                         return (ENETDOWN);
2978
2979                 if (ifp != NULL &&
2980                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2981                         struct in6_ifaddr *ia;
2982
2983                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2984                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2985                         if (ia == NULL)
2986                                 return (EADDRNOTAVAIL);
2987                         ifa_free(&ia->ia_ifa);
2988                 }
2989                 /*
2990                  * We store the address anyway, and let in6_selectsrc()
2991                  * validate the specified address.  This is because ipi6_addr
2992                  * may not have enough information about its scope zone, and
2993                  * we may need additional information (such as outgoing
2994                  * interface or the scope zone of a destination address) to
2995                  * disambiguate the scope.
2996                  * XXX: the delay of the validation may confuse the
2997                  * application when it is used as a sticky option.
2998                  */
2999                 if (opt->ip6po_pktinfo == NULL) {
3000                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
3001                             M_IP6OPT, M_NOWAIT);
3002                         if (opt->ip6po_pktinfo == NULL)
3003                                 return (ENOBUFS);
3004                 }
3005                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
3006                 break;
3007         }
3008
3009         case IPV6_2292HOPLIMIT:
3010         case IPV6_HOPLIMIT:
3011         {
3012                 int *hlimp;
3013
3014                 /*
3015                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
3016                  * to simplify the ordering among hoplimit options.
3017                  */
3018                 if (optname == IPV6_HOPLIMIT && sticky)
3019                         return (ENOPROTOOPT);
3020
3021                 if (len != sizeof(int))
3022                         return (EINVAL);
3023                 hlimp = (int *)buf;
3024                 if (*hlimp < -1 || *hlimp > 255)
3025                         return (EINVAL);
3026
3027                 opt->ip6po_hlim = *hlimp;
3028                 break;
3029         }
3030
3031         case IPV6_TCLASS:
3032         {
3033                 int tclass;
3034
3035                 if (len != sizeof(int))
3036                         return (EINVAL);
3037                 tclass = *(int *)buf;
3038                 if (tclass < -1 || tclass > 255)
3039                         return (EINVAL);
3040
3041                 opt->ip6po_tclass = tclass;
3042                 break;
3043         }
3044
3045         case IPV6_2292NEXTHOP:
3046         case IPV6_NEXTHOP:
3047                 if (cred != NULL) {
3048                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3049                         if (error)
3050                                 return (error);
3051                 }
3052
3053                 if (len == 0) { /* just remove the option */
3054                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
3055                         break;
3056                 }
3057
3058                 /* check if cmsg_len is large enough for sa_len */
3059                 if (len < sizeof(struct sockaddr) || len < *buf)
3060                         return (EINVAL);
3061
3062                 switch (((struct sockaddr *)buf)->sa_family) {
3063                 case AF_INET6:
3064                 {
3065                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
3066                         int error;
3067
3068                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
3069                                 return (EINVAL);
3070
3071                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
3072                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
3073                                 return (EINVAL);
3074                         }
3075                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
3076                             != 0) {
3077                                 return (error);
3078                         }
3079                         break;
3080                 }
3081                 case AF_LINK:   /* should eventually be supported */
3082                 default:
3083                         return (EAFNOSUPPORT);
3084                 }
3085
3086                 /* turn off the previous option, then set the new option. */
3087                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
3088                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
3089                 if (opt->ip6po_nexthop == NULL)
3090                         return (ENOBUFS);
3091                 bcopy(buf, opt->ip6po_nexthop, *buf);
3092                 break;
3093
3094         case IPV6_2292HOPOPTS:
3095         case IPV6_HOPOPTS:
3096         {
3097                 struct ip6_hbh *hbh;
3098                 int hbhlen;
3099
3100                 /*
3101                  * XXX: We don't allow a non-privileged user to set ANY HbH
3102                  * options, since per-option restriction has too much
3103                  * overhead.
3104                  */
3105                 if (cred != NULL) {
3106                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3107                         if (error)
3108                                 return (error);
3109                 }
3110
3111                 if (len == 0) {
3112                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
3113                         break;  /* just remove the option */
3114                 }
3115
3116                 /* message length validation */
3117                 if (len < sizeof(struct ip6_hbh))
3118                         return (EINVAL);
3119                 hbh = (struct ip6_hbh *)buf;
3120                 hbhlen = (hbh->ip6h_len + 1) << 3;
3121                 if (len != hbhlen)
3122                         return (EINVAL);
3123
3124                 /* turn off the previous option, then set the new option. */
3125                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
3126                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
3127                 if (opt->ip6po_hbh == NULL)
3128                         return (ENOBUFS);
3129                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
3130
3131                 break;
3132         }
3133
3134         case IPV6_2292DSTOPTS:
3135         case IPV6_DSTOPTS:
3136         case IPV6_RTHDRDSTOPTS:
3137         {
3138                 struct ip6_dest *dest, **newdest = NULL;
3139                 int destlen;
3140
3141                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
3142                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3143                         if (error)
3144                                 return (error);
3145                 }
3146
3147                 if (len == 0) {
3148                         ip6_clearpktopts(opt, optname);
3149                         break;  /* just remove the option */
3150                 }
3151
3152                 /* message length validation */
3153                 if (len < sizeof(struct ip6_dest))
3154                         return (EINVAL);
3155                 dest = (struct ip6_dest *)buf;
3156                 destlen = (dest->ip6d_len + 1) << 3;
3157                 if (len != destlen)
3158                         return (EINVAL);
3159
3160                 /*
3161                  * Determine the position that the destination options header
3162                  * should be inserted; before or after the routing header.
3163                  */
3164                 switch (optname) {
3165                 case IPV6_2292DSTOPTS:
3166                         /*
3167                          * The old advacned API is ambiguous on this point.
3168                          * Our approach is to determine the position based
3169                          * according to the existence of a routing header.
3170                          * Note, however, that this depends on the order of the
3171                          * extension headers in the ancillary data; the 1st
3172                          * part of the destination options header must appear
3173                          * before the routing header in the ancillary data,
3174                          * too.
3175                          * RFC3542 solved the ambiguity by introducing
3176                          * separate ancillary data or option types.
3177                          */
3178                         if (opt->ip6po_rthdr == NULL)
3179                                 newdest = &opt->ip6po_dest1;
3180                         else
3181                                 newdest = &opt->ip6po_dest2;
3182                         break;
3183                 case IPV6_RTHDRDSTOPTS:
3184                         newdest = &opt->ip6po_dest1;
3185                         break;
3186                 case IPV6_DSTOPTS:
3187                         newdest = &opt->ip6po_dest2;
3188                         break;
3189                 }
3190
3191                 /* turn off the previous option, then set the new option. */
3192                 ip6_clearpktopts(opt, optname);
3193                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3194                 if (*newdest == NULL)
3195                         return (ENOBUFS);
3196                 bcopy(dest, *newdest, destlen);
3197
3198                 break;
3199         }
3200
3201         case IPV6_2292RTHDR:
3202         case IPV6_RTHDR:
3203         {
3204                 struct ip6_rthdr *rth;
3205                 int rthlen;
3206
3207                 if (len == 0) {
3208                         ip6_clearpktopts(opt, IPV6_RTHDR);
3209                         break;  /* just remove the option */
3210                 }
3211
3212                 /* message length validation */
3213                 if (len < sizeof(struct ip6_rthdr))
3214                         return (EINVAL);
3215                 rth = (struct ip6_rthdr *)buf;
3216                 rthlen = (rth->ip6r_len + 1) << 3;
3217                 if (len != rthlen)
3218                         return (EINVAL);
3219
3220                 switch (rth->ip6r_type) {
3221                 case IPV6_RTHDR_TYPE_0:
3222                         if (rth->ip6r_len == 0) /* must contain one addr */
3223                                 return (EINVAL);
3224                         if (rth->ip6r_len % 2) /* length must be even */
3225                                 return (EINVAL);
3226                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3227                                 return (EINVAL);
3228                         break;
3229                 default:
3230                         return (EINVAL);        /* not supported */
3231                 }
3232
3233                 /* turn off the previous option */
3234                 ip6_clearpktopts(opt, IPV6_RTHDR);
3235                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3236                 if (opt->ip6po_rthdr == NULL)
3237                         return (ENOBUFS);
3238                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3239
3240                 break;
3241         }
3242
3243         case IPV6_USE_MIN_MTU:
3244                 if (len != sizeof(int))
3245                         return (EINVAL);
3246                 minmtupolicy = *(int *)buf;
3247                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3248                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3249                     minmtupolicy != IP6PO_MINMTU_ALL) {
3250                         return (EINVAL);
3251                 }
3252                 opt->ip6po_minmtu = minmtupolicy;
3253                 break;
3254
3255         case IPV6_DONTFRAG:
3256                 if (len != sizeof(int))
3257                         return (EINVAL);
3258
3259                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3260                         /*
3261                          * we ignore this option for TCP sockets.
3262                          * (RFC3542 leaves this case unspecified.)
3263                          */
3264                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3265                 } else
3266                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3267                 break;
3268
3269         case IPV6_PREFER_TEMPADDR:
3270                 if (len != sizeof(int))
3271                         return (EINVAL);
3272                 preftemp = *(int *)buf;
3273                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3274                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3275                     preftemp != IP6PO_TEMPADDR_PREFER) {
3276                         return (EINVAL);
3277                 }
3278                 opt->ip6po_prefer_tempaddr = preftemp;
3279                 break;
3280
3281         default:
3282                 return (ENOPROTOOPT);
3283         } /* end of switch */
3284
3285         return (0);
3286 }
3287
3288 /*
3289  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3290  * packet to the input queue of a specified interface.  Note that this
3291  * calls the output routine of the loopback "driver", but with an interface
3292  * pointer that might NOT be &loif -- easier than replicating that code here.
3293  */
3294 void
3295 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3296 {
3297         struct mbuf *copym;
3298         struct ip6_hdr *ip6;
3299
3300         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3301         if (copym == NULL)
3302                 return;
3303
3304         /*
3305          * Make sure to deep-copy IPv6 header portion in case the data
3306          * is in an mbuf cluster, so that we can safely override the IPv6
3307          * header portion later.
3308          */
3309         if (!M_WRITABLE(copym) ||
3310             copym->m_len < sizeof(struct ip6_hdr)) {
3311                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3312                 if (copym == NULL)
3313                         return;
3314         }
3315         ip6 = mtod(copym, struct ip6_hdr *);
3316         /*
3317          * clear embedded scope identifiers if necessary.
3318          * in6_clearscope will touch the addresses only when necessary.
3319          */
3320         in6_clearscope(&ip6->ip6_src);
3321         in6_clearscope(&ip6->ip6_dst);
3322         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3323                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3324                     CSUM_PSEUDO_HDR;
3325                 copym->m_pkthdr.csum_data = 0xffff;
3326         }
3327         if_simloop(ifp, copym, AF_INET6, 0);
3328 }
3329
3330 /*
3331  * Chop IPv6 header off from the payload.
3332  */
3333 static int
3334 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3335 {
3336         struct mbuf *mh;
3337         struct ip6_hdr *ip6;
3338
3339         ip6 = mtod(m, struct ip6_hdr *);
3340         if (m->m_len > sizeof(*ip6)) {
3341                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3342                 if (mh == NULL) {
3343                         m_freem(m);
3344                         return ENOBUFS;
3345                 }
3346                 m_move_pkthdr(mh, m);
3347                 M_ALIGN(mh, sizeof(*ip6));
3348                 m->m_len -= sizeof(*ip6);
3349                 m->m_data += sizeof(*ip6);
3350                 mh->m_next = m;
3351                 m = mh;
3352                 m->m_len = sizeof(*ip6);
3353                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3354         }
3355         exthdrs->ip6e_ip6 = m;
3356         return 0;
3357 }
3358
3359 /*
3360  * Compute IPv6 extension header length.
3361  */
3362 int
3363 ip6_optlen(struct inpcb *inp)
3364 {
3365         int len;
3366
3367         if (!inp->in6p_outputopts)
3368                 return 0;
3369
3370         len = 0;
3371 #define elen(x) \
3372     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3373
3374         len += elen(inp->in6p_outputopts->ip6po_hbh);
3375         if (inp->in6p_outputopts->ip6po_rthdr)
3376                 /* dest1 is valid with rthdr only */
3377                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3378         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3379         len += elen(inp->in6p_outputopts->ip6po_dest2);
3380         return len;
3381 #undef elen
3382 }