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_private.h>
  96 #include <net/if_vlan_var.h>
  97 #include <net/if_llatbl.h>
  98 #include <net/ethernet.h>
  99 #include <net/netisr.h>
 100 #include <net/route.h>
 101 #include <net/route/nhop.h>
 102 #include <net/pfil.h>
 103 #include <net/rss_config.h>
 104 #include <net/vnet.h>
 105
 106 #include <netinet/in.h>
 107 #include <netinet/in_var.h>
 108 #include <netinet/ip_var.h>
 109 #include <netinet6/in6_fib.h>
 110 #include <netinet6/in6_var.h>
 111 #include <netinet/ip6.h>
 112 #include <netinet/icmp6.h>
 113 #include <netinet6/ip6_var.h>
 114 #include <netinet/in_pcb.h>
 115 #include <netinet/tcp_var.h>
 116 #include <netinet6/nd6.h>
 117 #include <netinet6/in6_rss.h>
 118
 119 #include <netipsec/ipsec_support.h>
 120 #if defined(SCTP) || defined(SCTP_SUPPORT)
 121 #include <netinet/sctp.h>
 122 #include <netinet/sctp_crc32.h>
 123 #endif
 124
 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                         m_freem(m);
 340                         error = EAGAIN;
 341                         goto done;
 342                 }
 343                 /*
 344                  * Always stamp tags that include NIC ktls.
 345                  */
 346                 stamp_tag = true;
 347         }
 348 #endif
 349 #ifdef RATELIMIT
 350         if (inp != NULL && mst == NULL) {
 351                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 352                     (inp->inp_snd_tag != NULL &&
 353                     inp->inp_snd_tag->ifp != ifp))
 354                         in_pcboutput_txrtlmt(inp, ifp, m);
 355
 356                 if (inp->inp_snd_tag != NULL)
 357                         mst = inp->inp_snd_tag;
 358         }
 359 #endif
 360         if (stamp_tag && mst != NULL) {
 361                 KASSERT(m->m_pkthdr.rcvif == NULL,
 362                     ("trying to add a send tag to a forwarded packet"));
 363                 if (mst->ifp != ifp) {
 364                         m_freem(m);
 365                         error = EAGAIN;
 366                         goto done;
 367                 }
 368
 369                 /* stamp send tag on mbuf */
 370                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 371                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 372         }
 373
 374         error = nd6_output_ifp(ifp, origifp, m, dst, (struct route *)ro);
 375
 376 done:
 377         /* Check for route change invalidating send tags. */
 378 #ifdef KERN_TLS
 379         if (tls != NULL) {
 380                 if (error == EAGAIN)
 381                         error = ktls_output_eagain(inp, tls);
 382                 ktls_free(tls);
 383         }
 384 #endif
 385 #ifdef RATELIMIT
 386         if (error == EAGAIN)
 387                 in_pcboutput_eagain(inp);
 388 #endif
 389         return (error);
 390 }
 391
 392 /*
 393  * IP6 output.
 394  * The packet in mbuf chain m contains a skeletal IP6 header (with pri, len,
 395  * nxt, hlim, src, dst).
 396  * This function may modify ver and hlim only.
 397  * The mbuf chain containing the packet will be freed.
 398  * The mbuf opt, if present, will not be freed.
 399  * If route_in6 ro is present and has ro_nh initialized, route lookup would be
 400  * skipped and ro->ro_nh would be used. If ro is present but ro->ro_nh is NULL,
 401  * then result of route lookup is stored in ro->ro_nh.
 402  *
 403  * Type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and nd_ifinfo.linkmtu
 404  * is uint32_t.  So we use u_long to hold largest one, which is rt_mtu.
 405  *
 406  * ifpp - XXX: just for statistics
 407  */
 408 int
 409 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 410     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 411     struct ifnet **ifpp, struct inpcb *inp)
 412 {
 413         struct ip6_hdr *ip6;
 414         struct ifnet *ifp, *origifp;
 415         struct mbuf *m = m0;
 416         struct mbuf *mprev;
 417         struct route_in6 *ro_pmtu;
 418         struct nhop_object *nh;
 419         struct sockaddr_in6 *dst, sin6, src_sa, dst_sa;
 420         struct in6_addr odst;
 421         u_char *nexthdrp;
 422         int tlen, len;
 423         int error = 0;
 424         int vlan_pcp = -1;
 425         struct in6_ifaddr *ia = NULL;
 426         u_long mtu;
 427         int alwaysfrag, dontfrag;
 428         u_int32_t optlen, plen = 0, unfragpartlen;
 429         struct ip6_exthdrs exthdrs;
 430         struct in6_addr src0, dst0;
 431         u_int32_t zone;
 432         bool hdrsplit;
 433         int sw_csum, tso;
 434         int needfiblookup;
 435         uint32_t fibnum;
 436         struct m_tag *fwd_tag = NULL;
 437         uint32_t id;
 438
 439         NET_EPOCH_ASSERT();
 440
 441         if (inp != NULL) {
 442                 INP_LOCK_ASSERT(inp);
 443                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 444                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 445                         /* Unconditionally set flowid. */
 446                         m->m_pkthdr.flowid = inp->inp_flowid;
 447                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 448                 }
 449                 if ((inp->inp_flags2 & INP_2PCP_SET) != 0)
 450                         vlan_pcp = (inp->inp_flags2 & INP_2PCP_MASK) >>
 451                             INP_2PCP_SHIFT;
 452 #ifdef NUMA
 453                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 454 #endif
 455         }
 456
 457 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 458         /*
 459          * IPSec checking which handles several cases.
 460          * FAST IPSEC: We re-injected the packet.
 461          * XXX: need scope argument.
 462          */
 463         if (IPSEC_ENABLED(ipv6)) {
 464                 m = mb_unmapped_to_ext(m);
 465                 if (m == NULL) {
 466                         IP6STAT_INC(ip6s_odropped);
 467                         error = ENOBUFS;
 468                         goto bad;
 469                 }
 470                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 471                         if (error == EINPROGRESS)
 472                                 error = 0;
 473                         goto done;
 474                 }
 475         }
 476 #endif /* IPSEC */
 477
 478         /* Source address validation. */
 479         ip6 = mtod(m, struct ip6_hdr *);
 480         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 481             (flags & IPV6_UNSPECSRC) == 0) {
 482                 error = EOPNOTSUPP;
 483                 IP6STAT_INC(ip6s_badscope);
 484                 goto bad;
 485         }
 486         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 487                 error = EOPNOTSUPP;
 488                 IP6STAT_INC(ip6s_badscope);
 489                 goto bad;
 490         }
 491
 492         /*
 493          * If we are given packet options to add extension headers prepare them.
 494          * Calculate the total length of the extension header chain.
 495          * Keep the length of the unfragmentable part for fragmentation.
 496          */
 497         bzero(&exthdrs, sizeof(exthdrs));
 498         optlen = 0;
 499         unfragpartlen = sizeof(struct ip6_hdr);
 500         if (opt) {
 501                 /* Hop-by-Hop options header. */
 502                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh, optlen);
 503
 504                 /* Destination options header (1st part). */
 505                 if (opt->ip6po_rthdr) {
 506 #ifndef RTHDR_SUPPORT_IMPLEMENTED
 507                         /*
 508                          * If there is a routing header, discard the packet
 509                          * right away here. RH0/1 are obsolete and we do not
 510                          * currently support RH2/3/4.
 511                          * People trying to use RH253/254 may want to disable
 512                          * this check.
 513                          * The moment we do support any routing header (again)
 514                          * this block should check the routing type more
 515                          * selectively.
 516                          */
 517                         error = EINVAL;
 518                         goto bad;
 519 #endif
 520
 521                         /*
 522                          * Destination options header (1st part).
 523                          * This only makes sense with a routing header.
 524                          * See Section 9.2 of RFC 3542.
 525                          * Disabling this part just for MIP6 convenience is
 526                          * a bad idea.  We need to think carefully about a
 527                          * way to make the advanced API coexist with MIP6
 528                          * options, which might automatically be inserted in
 529                          * the kernel.
 530                          */
 531                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1,
 532                             optlen);
 533                 }
 534                 /* Routing header. */
 535                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr, optlen);
 536
 537                 unfragpartlen += optlen;
 538
 539                 /*
 540                  * NOTE: we don't add AH/ESP length here (done in
 541                  * ip6_ipsec_output()).
 542                  */
 543
 544                 /* Destination options header (2nd part). */
 545                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2, optlen);
 546         }
 547
 548         /*
 549          * If there is at least one extension header,
 550          * separate IP6 header from the payload.
 551          */
 552         hdrsplit = false;
 553         if (optlen) {
 554                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 555                         m = NULL;
 556                         goto freehdrs;
 557                 }
 558                 m = exthdrs.ip6e_ip6;
 559                 ip6 = mtod(m, struct ip6_hdr *);
 560                 hdrsplit = true;
 561         }
 562
 563         /* Adjust mbuf packet header length. */
 564         m->m_pkthdr.len += optlen;
 565         plen = m->m_pkthdr.len - sizeof(*ip6);
 566
 567         /* If this is a jumbo payload, insert a jumbo payload option. */
 568         if (plen > IPV6_MAXPACKET) {
 569                 if (!hdrsplit) {
 570                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 571                                 m = NULL;
 572                                 goto freehdrs;
 573                         }
 574                         m = exthdrs.ip6e_ip6;
 575                         ip6 = mtod(m, struct ip6_hdr *);
 576                         hdrsplit = true;
 577                 }
 578                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 579                         goto freehdrs;
 580                 ip6->ip6_plen = 0;
 581         } else
 582                 ip6->ip6_plen = htons(plen);
 583         nexthdrp = &ip6->ip6_nxt;
 584
 585         if (optlen) {
 586                 /*
 587                  * Concatenate headers and fill in next header fields.
 588                  * Here we have, on "m"
 589                  *      IPv6 payload
 590                  * and we insert headers accordingly.
 591                  * Finally, we should be getting:
 592                  *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload].
 593                  *
 594                  * During the header composing process "m" points to IPv6
 595                  * header.  "mprev" points to an extension header prior to esp.
 596                  */
 597                 mprev = m;
 598
 599                 /*
 600                  * We treat dest2 specially.  This makes IPsec processing
 601                  * much easier.  The goal here is to make mprev point the
 602                  * mbuf prior to dest2.
 603                  *
 604                  * Result: IPv6 dest2 payload.
 605                  * m and mprev will point to IPv6 header.
 606                  */
 607                 if (exthdrs.ip6e_dest2) {
 608                         if (!hdrsplit)
 609                                 panic("%s:%d: assumption failed: "
 610                                     "hdr not split: hdrsplit %d exthdrs %p",
 611                                     __func__, __LINE__, hdrsplit, &exthdrs);
 612                         exthdrs.ip6e_dest2->m_next = m->m_next;
 613                         m->m_next = exthdrs.ip6e_dest2;
 614                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 615                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 616                 }
 617
 618                 /*
 619                  * Result: IPv6 hbh dest1 rthdr dest2 payload.
 620                  * m will point to IPv6 header.  mprev will point to the
 621                  * extension header prior to dest2 (rthdr in the above case).
 622                  */
 623                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 624                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 625                            IPPROTO_DSTOPTS);
 626                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 627                            IPPROTO_ROUTING);
 628         }
 629
 630         IP6STAT_INC(ip6s_localout);
 631
 632         /* Route packet. */
 633         ro_pmtu = ro;
 634         if (opt && opt->ip6po_rthdr)
 635                 ro = &opt->ip6po_route;
 636         if (ro != NULL)
 637                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 638         else
 639                 dst = &sin6;
 640         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 641
 642 again:
 643         /*
 644          * If specified, try to fill in the traffic class field.
 645          * Do not override if a non-zero value is already set.
 646          * We check the diffserv field and the ECN field separately.
 647          */
 648         if (opt && opt->ip6po_tclass >= 0) {
 649                 int mask = 0;
 650
 651                 if (IPV6_DSCP(ip6) == 0)
 652                         mask |= 0xfc;
 653                 if (IPV6_ECN(ip6) == 0)
 654                         mask |= 0x03;
 655                 if (mask != 0)
 656                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 657         }
 658
 659         /* Fill in or override the hop limit field, if necessary. */
 660         if (opt && opt->ip6po_hlim != -1)
 661                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 662         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 663                 if (im6o != NULL)
 664                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 665                 else
 666                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 667         }
 668
 669         if (ro == NULL || ro->ro_nh == NULL) {
 670                 bzero(dst, sizeof(*dst));
 671                 dst->sin6_family = AF_INET6;
 672                 dst->sin6_len = sizeof(*dst);
 673                 dst->sin6_addr = ip6->ip6_dst;
 674         }
 675         /*
 676          * Validate route against routing table changes.
 677          * Make sure that the address family is set in route.
 678          */
 679         nh = NULL;
 680         ifp = NULL;
 681         mtu = 0;
 682         if (ro != NULL) {
 683                 if (ro->ro_nh != NULL && inp != NULL) {
 684                         ro->ro_dst.sin6_family = AF_INET6; /* XXX KASSERT? */
 685                         NH_VALIDATE((struct route *)ro, &inp->inp_rt_cookie,
 686                             fibnum);
 687                 }
 688                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 689                     (!NH_IS_VALID(ro->ro_nh) ||
 690                     ro->ro_dst.sin6_family != AF_INET6 ||
 691                     !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)))
 692                         RO_INVALIDATE_CACHE(ro);
 693
 694                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 695                     ro->ro_dst.sin6_family == AF_INET6 &&
 696                     IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 697                         /* Nexthop is valid and contains valid ifp */
 698                         nh = ro->ro_nh;
 699                 } else {
 700                         if (ro->ro_lle)
 701                                 LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 702                         ro->ro_lle = NULL;
 703                         if (fwd_tag == NULL) {
 704                                 bzero(&dst_sa, sizeof(dst_sa));
 705                                 dst_sa.sin6_family = AF_INET6;
 706                                 dst_sa.sin6_len = sizeof(dst_sa);
 707                                 dst_sa.sin6_addr = ip6->ip6_dst;
 708                         }
 709                         error = in6_selectroute(&dst_sa, opt, im6o, ro, &ifp,
 710                             &nh, fibnum, m->m_pkthdr.flowid);
 711                         if (error != 0) {
 712                                 IP6STAT_INC(ip6s_noroute);
 713                                 if (ifp != NULL)
 714                                         in6_ifstat_inc(ifp, ifs6_out_discard);
 715                                 goto bad;
 716                         }
 717                         /*
 718                          * At this point at least @ifp is not NULL
 719                          * Can be the case when dst is multicast, link-local or
 720                          * interface is explicitly specificed by the caller.
 721                          */
 722                 }
 723                 if (nh == NULL) {
 724                         /*
 725                          * If in6_selectroute() does not return a nexthop
 726                          * dst may not have been updated.
 727                          */
 728                         *dst = dst_sa;  /* XXX */
 729                         origifp = ifp;
 730                         mtu = ifp->if_mtu;
 731                 } else {
 732                         ifp = nh->nh_ifp;
 733                         origifp = nh->nh_aifp;
 734                         ia = (struct in6_ifaddr *)(nh->nh_ifa);
 735                         counter_u64_add(nh->nh_pksent, 1);
 736                 }
 737         } else {
 738                 struct nhop_object *nh;
 739                 struct in6_addr kdst;
 740                 uint32_t scopeid;
 741
 742                 if (fwd_tag == NULL) {
 743                         bzero(&dst_sa, sizeof(dst_sa));
 744                         dst_sa.sin6_family = AF_INET6;
 745                         dst_sa.sin6_len = sizeof(dst_sa);
 746                         dst_sa.sin6_addr = ip6->ip6_dst;
 747                 }
 748
 749                 if (IN6_IS_ADDR_MULTICAST(&dst_sa.sin6_addr) &&
 750                     im6o != NULL &&
 751                     (ifp = im6o->im6o_multicast_ifp) != NULL) {
 752                         /* We do not need a route lookup. */
 753                         *dst = dst_sa;  /* XXX */
 754                         origifp = ifp;
 755                         goto nonh6lookup;
 756                 }
 757
 758                 in6_splitscope(&dst_sa.sin6_addr, &kdst, &scopeid);
 759
 760                 if (IN6_IS_ADDR_MC_LINKLOCAL(&dst_sa.sin6_addr) ||
 761                     IN6_IS_ADDR_MC_NODELOCAL(&dst_sa.sin6_addr)) {
 762                         if (scopeid > 0) {
 763                                 ifp = in6_getlinkifnet(scopeid);
 764                                 if (ifp == NULL) {
 765                                         error = EHOSTUNREACH;
 766                                         goto bad;
 767                                 }
 768                                 *dst = dst_sa;  /* XXX */
 769                                 origifp = ifp;
 770                                 goto nonh6lookup;
 771                         }
 772                 }
 773
 774                 nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE,
 775                     m->m_pkthdr.flowid);
 776                 if (nh == NULL) {
 777                         IP6STAT_INC(ip6s_noroute);
 778                         /* No ifp in6_ifstat_inc(ifp, ifs6_out_discard); */
 779                         error = EHOSTUNREACH;
 780                         goto bad;
 781                 }
 782
 783                 ifp = nh->nh_ifp;
 784                 origifp = nh->nh_aifp;
 785                 ia = ifatoia6(nh->nh_ifa);
 786                 if (nh->nh_flags & NHF_GATEWAY)
 787                         dst->sin6_addr = nh->gw6_sa.sin6_addr;
 788                 else if (fwd_tag != NULL)
 789                         dst->sin6_addr = dst_sa.sin6_addr;
 790 nonh6lookup:
 791                 ;
 792         }
 793         /*
 794          * At this point ifp MUST be pointing to the valid transmit ifp.
 795          * origifp MUST be valid and pointing to either the same ifp or,
 796          * in case of loopback output, to the interface which ip6_src
 797          * belongs to.
 798          * Examples:
 799          *  fe80::1%em0 -> fe80::2%em0 -> ifp=em0, origifp=em0
 800          *  fe80::1%em0 -> fe80::1%em0 -> ifp=lo0, origifp=em0
 801          *  ::1 -> ::1 -> ifp=lo0, origifp=lo0
 802          *
 803          * mtu can be 0 and will be refined later.
 804          */
 805         KASSERT((ifp != NULL), ("output interface must not be NULL"));
 806         KASSERT((origifp != NULL), ("output address interface must not be NULL"));
 807
 808         if ((flags & IPV6_FORWARDING) == 0) {
 809                 /* XXX: the FORWARDING flag can be set for mrouting. */
 810                 in6_ifstat_inc(ifp, ifs6_out_request);
 811         }
 812
 813         /* Setup data structures for scope ID checks. */
 814         src0 = ip6->ip6_src;
 815         bzero(&src_sa, sizeof(src_sa));
 816         src_sa.sin6_family = AF_INET6;
 817         src_sa.sin6_len = sizeof(src_sa);
 818         src_sa.sin6_addr = ip6->ip6_src;
 819
 820         dst0 = ip6->ip6_dst;
 821         /* Re-initialize to be sure. */
 822         bzero(&dst_sa, sizeof(dst_sa));
 823         dst_sa.sin6_family = AF_INET6;
 824         dst_sa.sin6_len = sizeof(dst_sa);
 825         dst_sa.sin6_addr = ip6->ip6_dst;
 826
 827         /* Check for valid scope ID. */
 828         if (in6_setscope(&src0, origifp, &zone) == 0 &&
 829             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 830             in6_setscope(&dst0, origifp, &zone) == 0 &&
 831             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 832                 /*
 833                  * The outgoing interface is in the zone of the source
 834                  * and destination addresses.
 835                  *
 836                  */
 837         } else if ((origifp->if_flags & IFF_LOOPBACK) == 0 ||
 838             sa6_recoverscope(&src_sa) != 0 ||
 839             sa6_recoverscope(&dst_sa) != 0 ||
 840             dst_sa.sin6_scope_id == 0 ||
 841             (src_sa.sin6_scope_id != 0 &&
 842             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 843             ifnet_byindex(dst_sa.sin6_scope_id) == NULL) {
 844                 /*
 845                  * If the destination network interface is not a
 846                  * loopback interface, or the destination network
 847                  * address has no scope ID, or the source address has
 848                  * a scope ID set which is different from the
 849                  * destination address one, or there is no network
 850                  * interface representing this scope ID, the address
 851                  * pair is considered invalid.
 852                  */
 853                 IP6STAT_INC(ip6s_badscope);
 854                 in6_ifstat_inc(origifp, ifs6_out_discard);
 855                 if (error == 0)
 856                         error = EHOSTUNREACH; /* XXX */
 857                 goto bad;
 858         }
 859         /* All scope ID checks are successful. */
 860
 861         if (nh && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 862                 if (opt && opt->ip6po_nextroute.ro_nh) {
 863                         /*
 864                          * The nexthop is explicitly specified by the
 865                          * application.  We assume the next hop is an IPv6
 866                          * address.
 867                          */
 868                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 869                 }
 870                 else if ((nh->nh_flags & NHF_GATEWAY))
 871                         dst = &nh->gw6_sa;
 872         }
 873
 874         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 875                 m->m_flags &= ~(M_BCAST | M_MCAST); /* Just in case. */
 876         } else {
 877                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 878                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 879
 880                 /* Confirm that the outgoing interface supports multicast. */
 881                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 882                         IP6STAT_INC(ip6s_noroute);
 883                         in6_ifstat_inc(ifp, ifs6_out_discard);
 884                         error = ENETUNREACH;
 885                         goto bad;
 886                 }
 887                 if ((im6o == NULL && in6_mcast_loop) ||
 888                     (im6o && im6o->im6o_multicast_loop)) {
 889                         /*
 890                          * Loop back multicast datagram if not expressly
 891                          * forbidden to do so, even if we have not joined
 892                          * the address; protocols will filter it later,
 893                          * thus deferring a hash lookup and lock acquisition
 894                          * at the expense of an m_copym().
 895                          */
 896                         ip6_mloopback(ifp, m);
 897                 } else {
 898                         /*
 899                          * If we are acting as a multicast router, perform
 900                          * multicast forwarding as if the packet had just
 901                          * arrived on the interface to which we are about
 902                          * to send.  The multicast forwarding function
 903                          * recursively calls this function, using the
 904                          * IPV6_FORWARDING flag to prevent infinite recursion.
 905                          *
 906                          * Multicasts that are looped back by ip6_mloopback(),
 907                          * above, will be forwarded by the ip6_input() routine,
 908                          * if necessary.
 909                          */
 910                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 911                                 /*
 912                                  * XXX: ip6_mforward expects that rcvif is NULL
 913                                  * when it is called from the originating path.
 914                                  * However, it may not always be the case.
 915                                  */
 916                                 m->m_pkthdr.rcvif = NULL;
 917                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 918                                         m_freem(m);
 919                                         goto done;
 920                                 }
 921                         }
 922                 }
 923                 /*
 924                  * Multicasts with a hoplimit of zero may be looped back,
 925                  * above, but must not be transmitted on a network.
 926                  * Also, multicasts addressed to the loopback interface
 927                  * are not sent -- the above call to ip6_mloopback() will
 928                  * loop back a copy if this host actually belongs to the
 929                  * destination group on the loopback interface.
 930                  */
 931                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 932                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 933                         m_freem(m);
 934                         goto done;
 935                 }
 936         }
 937
 938         /*
 939          * Fill the outgoing inteface to tell the upper layer
 940          * to increment per-interface statistics.
 941          */
 942         if (ifpp)
 943                 *ifpp = ifp;
 944
 945         /* Determine path MTU. */
 946         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 947                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 948                 goto bad;
 949         KASSERT(mtu > 0, ("%s:%d: mtu %ld, ro_pmtu %p ro %p ifp %p "
 950             "alwaysfrag %d fibnum %u\n", __func__, __LINE__, mtu, ro_pmtu, ro,
 951             ifp, alwaysfrag, fibnum));
 952
 953         /*
 954          * The caller of this function may specify to use the minimum MTU
 955          * in some cases.
 956          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 957          * setting.  The logic is a bit complicated; by default, unicast
 958          * packets will follow path MTU while multicast packets will be sent at
 959          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 960          * including unicast ones will be sent at the minimum MTU.  Multicast
 961          * packets will always be sent at the minimum MTU unless
 962          * IP6PO_MINMTU_DISABLE is explicitly specified.
 963          * See RFC 3542 for more details.
 964          */
 965         if (mtu > IPV6_MMTU) {
 966                 if ((flags & IPV6_MINMTU))
 967                         mtu = IPV6_MMTU;
 968                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 969                         mtu = IPV6_MMTU;
 970                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 971                          (opt == NULL ||
 972                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 973                         mtu = IPV6_MMTU;
 974                 }
 975         }
 976
 977         /*
 978          * Clear embedded scope identifiers if necessary.
 979          * in6_clearscope() will touch the addresses only when necessary.
 980          */
 981         in6_clearscope(&ip6->ip6_src);
 982         in6_clearscope(&ip6->ip6_dst);
 983
 984         /*
 985          * If the outgoing packet contains a hop-by-hop options header,
 986          * it must be examined and processed even by the source node.
 987          * (RFC 2460, section 4.)
 988          */
 989         if (exthdrs.ip6e_hbh) {
 990                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 991                 u_int32_t dummy; /* XXX unused */
 992                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 993
 994 #ifdef DIAGNOSTIC
 995                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 996                         panic("ip6e_hbh is not contiguous");
 997 #endif
 998                 /*
 999                  *  XXX: if we have to send an ICMPv6 error to the sender,
1000                  *       we need the M_LOOP flag since icmp6_error() expects
1001                  *       the IPv6 and the hop-by-hop options header are
1002                  *       contiguous unless the flag is set.
1003                  */
1004                 m->m_flags |= M_LOOP;
1005                 m->m_pkthdr.rcvif = ifp;
1006                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
1007                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
1008                     &dummy, &plen) < 0) {
1009                         /* m was already freed at this point. */
1010                         error = EINVAL;/* better error? */
1011                         goto done;
1012                 }
1013                 m->m_flags &= ~M_LOOP; /* XXX */
1014                 m->m_pkthdr.rcvif = NULL;
1015         }
1016
1017         /* Jump over all PFIL processing if hooks are not active. */
1018         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
1019                 goto passout;
1020
1021         odst = ip6->ip6_dst;
1022         /* Run through list of hooks for output packets. */
1023         switch (pfil_mbuf_out(V_inet6_pfil_head, &m, ifp, inp)) {
1024         case PFIL_PASS:
1025                 ip6 = mtod(m, struct ip6_hdr *);
1026                 break;
1027         case PFIL_DROPPED:
1028                 error = EACCES;
1029                 /* FALLTHROUGH */
1030         case PFIL_CONSUMED:
1031                 goto done;
1032         }
1033
1034         needfiblookup = 0;
1035         /* See if destination IP address was changed by packet filter. */
1036         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
1037                 m->m_flags |= M_SKIP_FIREWALL;
1038                 /* If destination is now ourself drop to ip6_input(). */
1039                 if (in6_localip(&ip6->ip6_dst)) {
1040                         m->m_flags |= M_FASTFWD_OURS;
1041                         if (m->m_pkthdr.rcvif == NULL)
1042                                 m->m_pkthdr.rcvif = V_loif;
1043                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1044                                 m->m_pkthdr.csum_flags |=
1045                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1046                                 m->m_pkthdr.csum_data = 0xffff;
1047                         }
1048 #if defined(SCTP) || defined(SCTP_SUPPORT)
1049                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1050                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1051 #endif
1052                         error = netisr_queue(NETISR_IPV6, m);
1053                         goto done;
1054                 } else {
1055                         if (ro != NULL)
1056                                 RO_INVALIDATE_CACHE(ro);
1057                         needfiblookup = 1; /* Redo the routing table lookup. */
1058                 }
1059         }
1060         /* See if fib was changed by packet filter. */
1061         if (fibnum != M_GETFIB(m)) {
1062                 m->m_flags |= M_SKIP_FIREWALL;
1063                 fibnum = M_GETFIB(m);
1064                 if (ro != NULL)
1065                         RO_INVALIDATE_CACHE(ro);
1066                 needfiblookup = 1;
1067         }
1068         if (needfiblookup)
1069                 goto again;
1070
1071         /* See if local, if yes, send it to netisr. */
1072         if (m->m_flags & M_FASTFWD_OURS) {
1073                 if (m->m_pkthdr.rcvif == NULL)
1074                         m->m_pkthdr.rcvif = V_loif;
1075                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1076                         m->m_pkthdr.csum_flags |=
1077                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1078                         m->m_pkthdr.csum_data = 0xffff;
1079                 }
1080 #if defined(SCTP) || defined(SCTP_SUPPORT)
1081                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1082                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1083 #endif
1084                 error = netisr_queue(NETISR_IPV6, m);
1085                 goto done;
1086         }
1087         /* Or forward to some other address? */
1088         if ((m->m_flags & M_IP6_NEXTHOP) &&
1089             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
1090                 if (ro != NULL)
1091                         dst = (struct sockaddr_in6 *)&ro->ro_dst;
1092                 else
1093                         dst = &sin6;
1094                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
1095                 m->m_flags |= M_SKIP_FIREWALL;
1096                 m->m_flags &= ~M_IP6_NEXTHOP;
1097                 m_tag_delete(m, fwd_tag);
1098                 goto again;
1099         }
1100
1101 passout:
1102         if (vlan_pcp > -1)
1103                 EVL_APPLY_PRI(m, vlan_pcp);
1104
1105         /* Ensure the packet data is mapped if the interface requires it. */
1106         if ((ifp->if_capenable & IFCAP_MEXTPG) == 0) {
1107                 m = mb_unmapped_to_ext(m);
1108                 if (m == NULL) {
1109                         IP6STAT_INC(ip6s_odropped);
1110                         return (ENOBUFS);
1111                 }
1112         }
1113
1114         /*
1115          * Send the packet to the outgoing interface.
1116          * If necessary, do IPv6 fragmentation before sending.
1117          *
1118          * The logic here is rather complex:
1119          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
1120          * 1-a: send as is if tlen <= path mtu
1121          * 1-b: fragment if tlen > path mtu
1122          *
1123          * 2: if user asks us not to fragment (dontfrag == 1)
1124          * 2-a: send as is if tlen <= interface mtu
1125          * 2-b: error if tlen > interface mtu
1126          *
1127          * 3: if we always need to attach fragment header (alwaysfrag == 1)
1128          *      always fragment
1129          *
1130          * 4: if dontfrag == 1 && alwaysfrag == 1
1131          *      error, as we cannot handle this conflicting request.
1132          */
1133         sw_csum = m->m_pkthdr.csum_flags;
1134         if (!hdrsplit) {
1135                 tso = ((sw_csum & ifp->if_hwassist &
1136                     (CSUM_TSO | CSUM_INNER_TSO)) != 0) ? 1 : 0;
1137                 sw_csum &= ~ifp->if_hwassist;
1138         } else
1139                 tso = 0;
1140         /*
1141          * If we added extension headers, we will not do TSO and calculate the
1142          * checksums ourselves for now.
1143          * XXX-BZ  Need a framework to know when the NIC can handle it, even
1144          * with ext. hdrs.
1145          */
1146         ip6_output_delayed_csum(m, ifp, sw_csum, plen, optlen);
1147         /* XXX-BZ m->m_pkthdr.csum_flags &= ~ifp->if_hwassist; */
1148         tlen = m->m_pkthdr.len;
1149
1150         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1151                 dontfrag = 1;
1152         else
1153                 dontfrag = 0;
1154         if (dontfrag && alwaysfrag) {   /* Case 4. */
1155                 /* Conflicting request - can't transmit. */
1156                 error = EMSGSIZE;
1157                 goto bad;
1158         }
1159         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* Case 2-b. */
1160                 /*
1161                  * Even if the DONTFRAG option is specified, we cannot send the
1162                  * packet when the data length is larger than the MTU of the
1163                  * outgoing interface.
1164                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1165                  * application wanted to know the MTU value. Also return an
1166                  * error code (this is not described in the API spec).
1167                  */
1168                 if (inp != NULL)
1169                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1170                 error = EMSGSIZE;
1171                 goto bad;
1172         }
1173
1174         /* Transmit packet without fragmentation. */
1175         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* Cases 1-a and 2-a. */
1176                 struct in6_ifaddr *ia6;
1177
1178                 ip6 = mtod(m, struct ip6_hdr *);
1179                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1180                 if (ia6) {
1181                         /* Record statistics for this interface address. */
1182                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1183                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1184                             m->m_pkthdr.len);
1185                 }
1186                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1187                     (flags & IP_NO_SND_TAG_RL) ? false : true);
1188                 goto done;
1189         }
1190
1191         /* Try to fragment the packet.  Cases 1-b and 3. */
1192         if (mtu < IPV6_MMTU) {
1193                 /* Path MTU cannot be less than IPV6_MMTU. */
1194                 error = EMSGSIZE;
1195                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1196                 goto bad;
1197         } else if (ip6->ip6_plen == 0) {
1198                 /* Jumbo payload cannot be fragmented. */
1199                 error = EMSGSIZE;
1200                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1201                 goto bad;
1202         } else {
1203                 u_char nextproto;
1204
1205                 /*
1206                  * Too large for the destination or interface;
1207                  * fragment if possible.
1208                  * Must be able to put at least 8 bytes per fragment.
1209                  */
1210                 if (mtu > IPV6_MAXPACKET)
1211                         mtu = IPV6_MAXPACKET;
1212
1213                 len = (mtu - unfragpartlen - sizeof(struct ip6_frag)) & ~7;
1214                 if (len < 8) {
1215                         error = EMSGSIZE;
1216                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1217                         goto bad;
1218                 }
1219
1220                 /*
1221                  * If the interface will not calculate checksums on
1222                  * fragmented packets, then do it here.
1223                  * XXX-BZ handle the hw offloading case.  Need flags.
1224                  */
1225                 ip6_output_delayed_csum(m, ifp, m->m_pkthdr.csum_flags, plen,
1226                     optlen);
1227
1228                 /*
1229                  * Change the next header field of the last header in the
1230                  * unfragmentable part.
1231                  */
1232                 if (exthdrs.ip6e_rthdr) {
1233                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1234                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1235                 } else if (exthdrs.ip6e_dest1) {
1236                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1237                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1238                 } else if (exthdrs.ip6e_hbh) {
1239                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1240                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1241                 } else {
1242                         ip6 = mtod(m, struct ip6_hdr *);
1243                         nextproto = ip6->ip6_nxt;
1244                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1245                 }
1246
1247                 /*
1248                  * Loop through length of segment after first fragment,
1249                  * make new header and copy data of each part and link onto
1250                  * chain.
1251                  */
1252                 m0 = m;
1253                 id = htonl(ip6_randomid());
1254                 error = ip6_fragment(ifp, m, unfragpartlen, nextproto,len, id);
1255                 if (error != 0)
1256                         goto sendorfree;
1257
1258                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1259         }
1260
1261         /* Remove leading garbage. */
1262 sendorfree:
1263         m = m0->m_nextpkt;
1264         m0->m_nextpkt = 0;
1265         m_freem(m0);
1266         for (; m; m = m0) {
1267                 m0 = m->m_nextpkt;
1268                 m->m_nextpkt = 0;
1269                 if (error == 0) {
1270                         /* Record statistics for this interface address. */
1271                         if (ia) {
1272                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1273                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1274                                     m->m_pkthdr.len);
1275                         }
1276                         if (vlan_pcp > -1)
1277                                 EVL_APPLY_PRI(m, vlan_pcp);
1278                         error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1279                             true);
1280                 } else
1281                         m_freem(m);
1282         }
1283
1284         if (error == 0)
1285                 IP6STAT_INC(ip6s_fragmented);
1286
1287 done:
1288         return (error);
1289
1290 freehdrs:
1291         m_freem(exthdrs.ip6e_hbh);      /* m_freem() checks if mbuf is NULL. */
1292         m_freem(exthdrs.ip6e_dest1);
1293         m_freem(exthdrs.ip6e_rthdr);
1294         m_freem(exthdrs.ip6e_dest2);
1295         /* FALLTHROUGH */
1296 bad:
1297         if (m)
1298                 m_freem(m);
1299         goto done;
1300 }
1301
1302 static int
1303 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1304 {
1305         struct mbuf *m;
1306
1307         if (hlen > MCLBYTES)
1308                 return (ENOBUFS); /* XXX */
1309
1310         if (hlen > MLEN)
1311                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1312         else
1313                 m = m_get(M_NOWAIT, MT_DATA);
1314         if (m == NULL)
1315                 return (ENOBUFS);
1316         m->m_len = hlen;
1317         if (hdr)
1318                 bcopy(hdr, mtod(m, caddr_t), hlen);
1319
1320         *mp = m;
1321         return (0);
1322 }
1323
1324 /*
1325  * Insert jumbo payload option.
1326  */
1327 static int
1328 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1329 {
1330         struct mbuf *mopt;
1331         u_char *optbuf;
1332         u_int32_t v;
1333
1334 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1335
1336         /*
1337          * If there is no hop-by-hop options header, allocate new one.
1338          * If there is one but it doesn't have enough space to store the
1339          * jumbo payload option, allocate a cluster to store the whole options.
1340          * Otherwise, use it to store the options.
1341          */
1342         if (exthdrs->ip6e_hbh == NULL) {
1343                 mopt = m_get(M_NOWAIT, MT_DATA);
1344                 if (mopt == NULL)
1345                         return (ENOBUFS);
1346                 mopt->m_len = JUMBOOPTLEN;
1347                 optbuf = mtod(mopt, u_char *);
1348                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1349                 exthdrs->ip6e_hbh = mopt;
1350         } else {
1351                 struct ip6_hbh *hbh;
1352
1353                 mopt = exthdrs->ip6e_hbh;
1354                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1355                         /*
1356                          * XXX assumption:
1357                          * - exthdrs->ip6e_hbh is not referenced from places
1358                          *   other than exthdrs.
1359                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1360                          */
1361                         int oldoptlen = mopt->m_len;
1362                         struct mbuf *n;
1363
1364                         /*
1365                          * XXX: give up if the whole (new) hbh header does
1366                          * not fit even in an mbuf cluster.
1367                          */
1368                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1369                                 return (ENOBUFS);
1370
1371                         /*
1372                          * As a consequence, we must always prepare a cluster
1373                          * at this point.
1374                          */
1375                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1376                         if (n == NULL)
1377                                 return (ENOBUFS);
1378                         n->m_len = oldoptlen + JUMBOOPTLEN;
1379                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1380                             oldoptlen);
1381                         optbuf = mtod(n, caddr_t) + oldoptlen;
1382                         m_freem(mopt);
1383                         mopt = exthdrs->ip6e_hbh = n;
1384                 } else {
1385                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1386                         mopt->m_len += JUMBOOPTLEN;
1387                 }
1388                 optbuf[0] = IP6OPT_PADN;
1389                 optbuf[1] = 1;
1390
1391                 /*
1392                  * Adjust the header length according to the pad and
1393                  * the jumbo payload option.
1394                  */
1395                 hbh = mtod(mopt, struct ip6_hbh *);
1396                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1397         }
1398
1399         /* fill in the option. */
1400         optbuf[2] = IP6OPT_JUMBO;
1401         optbuf[3] = 4;
1402         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1403         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1404
1405         /* finally, adjust the packet header length */
1406         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1407
1408         return (0);
1409 #undef JUMBOOPTLEN
1410 }
1411
1412 /*
1413  * Insert fragment header and copy unfragmentable header portions.
1414  */
1415 static int
1416 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1417     struct ip6_frag **frghdrp)
1418 {
1419         struct mbuf *n, *mlast;
1420
1421         if (hlen > sizeof(struct ip6_hdr)) {
1422                 n = m_copym(m0, sizeof(struct ip6_hdr),
1423                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1424                 if (n == NULL)
1425                         return (ENOBUFS);
1426                 m->m_next = n;
1427         } else
1428                 n = m;
1429
1430         /* Search for the last mbuf of unfragmentable part. */
1431         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1432                 ;
1433
1434         if (M_WRITABLE(mlast) &&
1435             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1436                 /* use the trailing space of the last mbuf for the fragment hdr */
1437                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1438                     mlast->m_len);
1439                 mlast->m_len += sizeof(struct ip6_frag);
1440                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1441         } else {
1442                 /* allocate a new mbuf for the fragment header */
1443                 struct mbuf *mfrg;
1444
1445                 mfrg = m_get(M_NOWAIT, MT_DATA);
1446                 if (mfrg == NULL)
1447                         return (ENOBUFS);
1448                 mfrg->m_len = sizeof(struct ip6_frag);
1449                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1450                 mlast->m_next = mfrg;
1451         }
1452
1453         return (0);
1454 }
1455
1456 /*
1457  * Calculates IPv6 path mtu for destination @dst.
1458  * Resulting MTU is stored in @mtup.
1459  *
1460  * Returns 0 on success.
1461  */
1462 static int
1463 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1464 {
1465         struct epoch_tracker et;
1466         struct nhop_object *nh;
1467         struct in6_addr kdst;
1468         uint32_t scopeid;
1469         int error;
1470
1471         in6_splitscope(dst, &kdst, &scopeid);
1472
1473         NET_EPOCH_ENTER(et);
1474         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1475         if (nh != NULL)
1476                 error = ip6_calcmtu(nh->nh_ifp, dst, nh->nh_mtu, mtup, NULL, 0);
1477         else
1478                 error = EHOSTUNREACH;
1479         NET_EPOCH_EXIT(et);
1480
1481         return (error);
1482 }
1483
1484 /*
1485  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1486  * and cached data in @ro_pmtu.
1487  * MTU from (successful) route lookup is saved (along with dst)
1488  * inside @ro_pmtu to avoid subsequent route lookups after packet
1489  * filter processing.
1490  *
1491  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1492  * Returns 0 on success.
1493  */
1494 static int
1495 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1496     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1497     int *alwaysfragp, u_int fibnum, u_int proto)
1498 {
1499         struct nhop_object *nh;
1500         struct in6_addr kdst;
1501         uint32_t scopeid;
1502         struct sockaddr_in6 *sa6_dst, sin6;
1503         u_long mtu;
1504
1505         NET_EPOCH_ASSERT();
1506
1507         mtu = 0;
1508         if (ro_pmtu == NULL || do_lookup) {
1509                 /*
1510                  * Here ro_pmtu has final destination address, while
1511                  * ro might represent immediate destination.
1512                  * Use ro_pmtu destination since mtu might differ.
1513                  */
1514                 if (ro_pmtu != NULL) {
1515                         sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1516                         if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1517                                 ro_pmtu->ro_mtu = 0;
1518                 } else
1519                         sa6_dst = &sin6;
1520
1521                 if (ro_pmtu == NULL || ro_pmtu->ro_mtu == 0) {
1522                         bzero(sa6_dst, sizeof(*sa6_dst));
1523                         sa6_dst->sin6_family = AF_INET6;
1524                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1525                         sa6_dst->sin6_addr = *dst;
1526
1527                         in6_splitscope(dst, &kdst, &scopeid);
1528                         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1529                         if (nh != NULL) {
1530                                 mtu = nh->nh_mtu;
1531                                 if (ro_pmtu != NULL)
1532                                         ro_pmtu->ro_mtu = mtu;
1533                         }
1534                 } else
1535                         mtu = ro_pmtu->ro_mtu;
1536         }
1537
1538         if (ro_pmtu != NULL && ro_pmtu->ro_nh != NULL)
1539                 mtu = ro_pmtu->ro_nh->nh_mtu;
1540
1541         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1542 }
1543
1544 /*
1545  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1546  * hostcache data for @dst.
1547  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1548  *
1549  * Returns 0 on success.
1550  */
1551 static int
1552 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1553     u_long *mtup, int *alwaysfragp, u_int proto)
1554 {
1555         u_long mtu = 0;
1556         int alwaysfrag = 0;
1557         int error = 0;
1558
1559         if (rt_mtu > 0) {
1560                 u_int32_t ifmtu;
1561                 struct in_conninfo inc;
1562
1563                 bzero(&inc, sizeof(inc));
1564                 inc.inc_flags |= INC_ISIPV6;
1565                 inc.inc6_faddr = *dst;
1566
1567                 ifmtu = IN6_LINKMTU(ifp);
1568
1569                 /* TCP is known to react to pmtu changes so skip hc */
1570                 if (proto != IPPROTO_TCP)
1571                         mtu = tcp_hc_getmtu(&inc);
1572
1573                 if (mtu)
1574                         mtu = min(mtu, rt_mtu);
1575                 else
1576                         mtu = rt_mtu;
1577                 if (mtu == 0)
1578                         mtu = ifmtu;
1579                 else if (mtu < IPV6_MMTU) {
1580                         /*
1581                          * RFC2460 section 5, last paragraph:
1582                          * if we record ICMPv6 too big message with
1583                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1584                          * or smaller, with framgent header attached.
1585                          * (fragment header is needed regardless from the
1586                          * packet size, for translators to identify packets)
1587                          */
1588                         alwaysfrag = 1;
1589                         mtu = IPV6_MMTU;
1590                 }
1591         } else if (ifp) {
1592                 mtu = IN6_LINKMTU(ifp);
1593         } else
1594                 error = EHOSTUNREACH; /* XXX */
1595
1596         *mtup = mtu;
1597         if (alwaysfragp)
1598                 *alwaysfragp = alwaysfrag;
1599         return (error);
1600 }
1601
1602 /*
1603  * IP6 socket option processing.
1604  */
1605 int
1606 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1607 {
1608         int optdatalen, uproto;
1609         void *optdata;
1610         struct inpcb *inp = sotoinpcb(so);
1611         int error, optval;
1612         int level, op, optname;
1613         int optlen;
1614         struct thread *td;
1615 #ifdef  RSS
1616         uint32_t rss_bucket;
1617         int retval;
1618 #endif
1619
1620 /*
1621  * Don't use more than a quarter of mbuf clusters.  N.B.:
1622  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1623  * on LP64 architectures, so cast to u_long to avoid undefined
1624  * behavior.  ILP32 architectures cannot have nmbclusters
1625  * large enough to overflow for other reasons.
1626  */
1627 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1628
1629         level = sopt->sopt_level;
1630         op = sopt->sopt_dir;
1631         optname = sopt->sopt_name;
1632         optlen = sopt->sopt_valsize;
1633         td = sopt->sopt_td;
1634         error = 0;
1635         optval = 0;
1636         uproto = (int)so->so_proto->pr_protocol;
1637
1638         if (level != IPPROTO_IPV6) {
1639                 error = EINVAL;
1640
1641                 if (sopt->sopt_level == SOL_SOCKET &&
1642                     sopt->sopt_dir == SOPT_SET) {
1643                         switch (sopt->sopt_name) {
1644                         case SO_SETFIB:
1645                                 INP_WLOCK(inp);
1646                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1647                                 INP_WUNLOCK(inp);
1648                                 error = 0;
1649                                 break;
1650                         case SO_MAX_PACING_RATE:
1651 #ifdef RATELIMIT
1652                                 INP_WLOCK(inp);
1653                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1654                                 INP_WUNLOCK(inp);
1655                                 error = 0;
1656 #else
1657                                 error = EOPNOTSUPP;
1658 #endif
1659                                 break;
1660                         default:
1661                                 break;
1662                         }
1663                 }
1664         } else {                /* level == IPPROTO_IPV6 */
1665                 switch (op) {
1666                 case SOPT_SET:
1667                         switch (optname) {
1668                         case IPV6_2292PKTOPTIONS:
1669 #ifdef IPV6_PKTOPTIONS
1670                         case IPV6_PKTOPTIONS:
1671 #endif
1672                         {
1673                                 struct mbuf *m;
1674
1675                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1676                                         printf("ip6_ctloutput: mbuf limit hit\n");
1677                                         error = ENOBUFS;
1678                                         break;
1679                                 }
1680
1681                                 error = soopt_getm(sopt, &m); /* XXX */
1682                                 if (error != 0)
1683                                         break;
1684                                 error = soopt_mcopyin(sopt, m); /* XXX */
1685                                 if (error != 0)
1686                                         break;
1687                                 INP_WLOCK(inp);
1688                                 error = ip6_pcbopts(&inp->in6p_outputopts, m,
1689                                     so, sopt);
1690                                 INP_WUNLOCK(inp);
1691                                 m_freem(m); /* XXX */
1692                                 break;
1693                         }
1694
1695                         /*
1696                          * Use of some Hop-by-Hop options or some
1697                          * Destination options, might require special
1698                          * privilege.  That is, normal applications
1699                          * (without special privilege) might be forbidden
1700                          * from setting certain options in outgoing packets,
1701                          * and might never see certain options in received
1702                          * packets. [RFC 2292 Section 6]
1703                          * KAME specific note:
1704                          *  KAME prevents non-privileged users from sending or
1705                          *  receiving ANY hbh/dst options in order to avoid
1706                          *  overhead of parsing options in the kernel.
1707                          */
1708                         case IPV6_RECVHOPOPTS:
1709                         case IPV6_RECVDSTOPTS:
1710                         case IPV6_RECVRTHDRDSTOPTS:
1711                                 if (td != NULL) {
1712                                         error = priv_check(td,
1713                                             PRIV_NETINET_SETHDROPTS);
1714                                         if (error)
1715                                                 break;
1716                                 }
1717                                 /* FALLTHROUGH */
1718                         case IPV6_UNICAST_HOPS:
1719                         case IPV6_HOPLIMIT:
1720
1721                         case IPV6_RECVPKTINFO:
1722                         case IPV6_RECVHOPLIMIT:
1723                         case IPV6_RECVRTHDR:
1724                         case IPV6_RECVPATHMTU:
1725                         case IPV6_RECVTCLASS:
1726                         case IPV6_RECVFLOWID:
1727 #ifdef  RSS
1728                         case IPV6_RECVRSSBUCKETID:
1729 #endif
1730                         case IPV6_V6ONLY:
1731                         case IPV6_AUTOFLOWLABEL:
1732                         case IPV6_ORIGDSTADDR:
1733                         case IPV6_BINDANY:
1734                         case IPV6_VLAN_PCP:
1735                                 if (optname == IPV6_BINDANY && td != NULL) {
1736                                         error = priv_check(td,
1737                                             PRIV_NETINET_BINDANY);
1738                                         if (error)
1739                                                 break;
1740                                 }
1741
1742                                 if (optlen != sizeof(int)) {
1743                                         error = EINVAL;
1744                                         break;
1745                                 }
1746                                 error = sooptcopyin(sopt, &optval,
1747                                         sizeof optval, sizeof optval);
1748                                 if (error)
1749                                         break;
1750                                 switch (optname) {
1751                                 case IPV6_UNICAST_HOPS:
1752                                         if (optval < -1 || optval >= 256)
1753                                                 error = EINVAL;
1754                                         else {
1755                                                 /* -1 = kernel default */
1756                                                 inp->in6p_hops = optval;
1757                                                 if ((inp->inp_vflag &
1758                                                      INP_IPV4) != 0)
1759                                                         inp->inp_ip_ttl = optval;
1760                                         }
1761                                         break;
1762 #define OPTSET(bit) \
1763 do { \
1764         INP_WLOCK(inp); \
1765         if (optval) \
1766                 inp->inp_flags |= (bit); \
1767         else \
1768                 inp->inp_flags &= ~(bit); \
1769         INP_WUNLOCK(inp); \
1770 } while (/*CONSTCOND*/ 0)
1771 #define OPTSET2292(bit) \
1772 do { \
1773         INP_WLOCK(inp); \
1774         inp->inp_flags |= IN6P_RFC2292; \
1775         if (optval) \
1776                 inp->inp_flags |= (bit); \
1777         else \
1778                 inp->inp_flags &= ~(bit); \
1779         INP_WUNLOCK(inp); \
1780 } while (/*CONSTCOND*/ 0)
1781 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1782
1783 #define OPTSET2_N(bit, val) do {                                        \
1784         if (val)                                                        \
1785                 inp->inp_flags2 |= bit;                                 \
1786         else                                                            \
1787                 inp->inp_flags2 &= ~bit;                                \
1788 } while (0)
1789 #define OPTSET2(bit, val) do {                                          \
1790         INP_WLOCK(inp);                                                 \
1791         OPTSET2_N(bit, val);                                            \
1792         INP_WUNLOCK(inp);                                               \
1793 } while (0)
1794 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1795 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1796 do {                                                                    \
1797         INP_WLOCK(inp);                                                 \
1798         if (OPTBIT(IN6P_RFC2292)) {                                     \
1799                 error = EINVAL;                                         \
1800         } else {                                                        \
1801                 if (optval)                                             \
1802                         inp->inp_flags |= (bit);                        \
1803                 else                                                    \
1804                         inp->inp_flags &= ~(bit);                       \
1805         }                                                               \
1806         INP_WUNLOCK(inp);                                               \
1807 } while (/*CONSTCOND*/ 0)
1808
1809                                 case IPV6_RECVPKTINFO:
1810                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1811                                         break;
1812
1813                                 case IPV6_HOPLIMIT:
1814                                 {
1815                                         struct ip6_pktopts **optp;
1816
1817                                         /* cannot mix with RFC2292 */
1818                                         if (OPTBIT(IN6P_RFC2292)) {
1819                                                 error = EINVAL;
1820                                                 break;
1821                                         }
1822                                         INP_WLOCK(inp);
1823                                         if (inp->inp_flags & INP_DROPPED) {
1824                                                 INP_WUNLOCK(inp);
1825                                                 return (ECONNRESET);
1826                                         }
1827                                         optp = &inp->in6p_outputopts;
1828                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1829                                             (u_char *)&optval, sizeof(optval),
1830                                             optp, (td != NULL) ? td->td_ucred :
1831                                             NULL, uproto);
1832                                         INP_WUNLOCK(inp);
1833                                         break;
1834                                 }
1835
1836                                 case IPV6_RECVHOPLIMIT:
1837                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1838                                         break;
1839
1840                                 case IPV6_RECVHOPOPTS:
1841                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1842                                         break;
1843
1844                                 case IPV6_RECVDSTOPTS:
1845                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1846                                         break;
1847
1848                                 case IPV6_RECVRTHDRDSTOPTS:
1849                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1850                                         break;
1851
1852                                 case IPV6_RECVRTHDR:
1853                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1854                                         break;
1855
1856                                 case IPV6_RECVPATHMTU:
1857                                         /*
1858                                          * We ignore this option for TCP
1859                                          * sockets.
1860                                          * (RFC3542 leaves this case
1861                                          * unspecified.)
1862                                          */
1863                                         if (uproto != IPPROTO_TCP)
1864                                                 OPTSET(IN6P_MTU);
1865                                         break;
1866
1867                                 case IPV6_RECVFLOWID:
1868                                         OPTSET2(INP_RECVFLOWID, optval);
1869                                         break;
1870
1871 #ifdef  RSS
1872                                 case IPV6_RECVRSSBUCKETID:
1873                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1874                                         break;
1875 #endif
1876
1877                                 case IPV6_V6ONLY:
1878                                         INP_WLOCK(inp);
1879                                         if (inp->inp_lport ||
1880                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1881                                                 /*
1882                                                  * The socket is already bound.
1883                                                  */
1884                                                 INP_WUNLOCK(inp);
1885                                                 error = EINVAL;
1886                                                 break;
1887                                         }
1888                                         if (optval) {
1889                                                 inp->inp_flags |= IN6P_IPV6_V6ONLY;
1890                                                 inp->inp_vflag &= ~INP_IPV4;
1891                                         } else {
1892                                                 inp->inp_flags &= ~IN6P_IPV6_V6ONLY;
1893                                                 inp->inp_vflag |= INP_IPV4;
1894                                         }
1895                                         INP_WUNLOCK(inp);
1896                                         break;
1897                                 case IPV6_RECVTCLASS:
1898                                         /* cannot mix with RFC2292 XXX */
1899                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1900                                         break;
1901                                 case IPV6_AUTOFLOWLABEL:
1902                                         OPTSET(IN6P_AUTOFLOWLABEL);
1903                                         break;
1904
1905                                 case IPV6_ORIGDSTADDR:
1906                                         OPTSET2(INP_ORIGDSTADDR, optval);
1907                                         break;
1908                                 case IPV6_BINDANY:
1909                                         OPTSET(INP_BINDANY);
1910                                         break;
1911                                 case IPV6_VLAN_PCP:
1912                                         if ((optval >= -1) && (optval <=
1913                                             (INP_2PCP_MASK >> INP_2PCP_SHIFT))) {
1914                                                 if (optval == -1) {
1915                                                         INP_WLOCK(inp);
1916                                                         inp->inp_flags2 &=
1917                                                             ~(INP_2PCP_SET |
1918                                                             INP_2PCP_MASK);
1919                                                         INP_WUNLOCK(inp);
1920                                                 } else {
1921                                                         INP_WLOCK(inp);
1922                                                         inp->inp_flags2 |=
1923                                                             INP_2PCP_SET;
1924                                                         inp->inp_flags2 &=
1925                                                             ~INP_2PCP_MASK;
1926                                                         inp->inp_flags2 |=
1927                                                             optval <<
1928                                                             INP_2PCP_SHIFT;
1929                                                         INP_WUNLOCK(inp);
1930                                                 }
1931                                         } else
1932                                                 error = EINVAL;
1933                                         break;
1934                                 }
1935                                 break;
1936
1937                         case IPV6_TCLASS:
1938                         case IPV6_DONTFRAG:
1939                         case IPV6_USE_MIN_MTU:
1940                         case IPV6_PREFER_TEMPADDR:
1941                                 if (optlen != sizeof(optval)) {
1942                                         error = EINVAL;
1943                                         break;
1944                                 }
1945                                 error = sooptcopyin(sopt, &optval,
1946                                         sizeof optval, sizeof optval);
1947                                 if (error)
1948                                         break;
1949                                 {
1950                                         struct ip6_pktopts **optp;
1951                                         INP_WLOCK(inp);
1952                                         if (inp->inp_flags & INP_DROPPED) {
1953                                                 INP_WUNLOCK(inp);
1954                                                 return (ECONNRESET);
1955                                         }
1956                                         optp = &inp->in6p_outputopts;
1957                                         error = ip6_pcbopt(optname,
1958                                             (u_char *)&optval, sizeof(optval),
1959                                             optp, (td != NULL) ? td->td_ucred :
1960                                             NULL, uproto);
1961                                         INP_WUNLOCK(inp);
1962                                         break;
1963                                 }
1964
1965                         case IPV6_2292PKTINFO:
1966                         case IPV6_2292HOPLIMIT:
1967                         case IPV6_2292HOPOPTS:
1968                         case IPV6_2292DSTOPTS:
1969                         case IPV6_2292RTHDR:
1970                                 /* RFC 2292 */
1971                                 if (optlen != sizeof(int)) {
1972                                         error = EINVAL;
1973                                         break;
1974                                 }
1975                                 error = sooptcopyin(sopt, &optval,
1976                                         sizeof optval, sizeof optval);
1977                                 if (error)
1978                                         break;
1979                                 switch (optname) {
1980                                 case IPV6_2292PKTINFO:
1981                                         OPTSET2292(IN6P_PKTINFO);
1982                                         break;
1983                                 case IPV6_2292HOPLIMIT:
1984                                         OPTSET2292(IN6P_HOPLIMIT);
1985                                         break;
1986                                 case IPV6_2292HOPOPTS:
1987                                         /*
1988                                          * Check super-user privilege.
1989                                          * See comments for IPV6_RECVHOPOPTS.
1990                                          */
1991                                         if (td != NULL) {
1992                                                 error = priv_check(td,
1993                                                     PRIV_NETINET_SETHDROPTS);
1994                                                 if (error)
1995                                                         return (error);
1996                                         }
1997                                         OPTSET2292(IN6P_HOPOPTS);
1998                                         break;
1999                                 case IPV6_2292DSTOPTS:
2000                                         if (td != NULL) {
2001                                                 error = priv_check(td,
2002                                                     PRIV_NETINET_SETHDROPTS);
2003                                                 if (error)
2004                                                         return (error);
2005                                         }
2006                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
2007                                         break;
2008                                 case IPV6_2292RTHDR:
2009                                         OPTSET2292(IN6P_RTHDR);
2010                                         break;
2011                                 }
2012                                 break;
2013                         case IPV6_PKTINFO:
2014                         case IPV6_HOPOPTS:
2015                         case IPV6_RTHDR:
2016                         case IPV6_DSTOPTS:
2017                         case IPV6_RTHDRDSTOPTS:
2018                         case IPV6_NEXTHOP:
2019                         {
2020                                 /* new advanced API (RFC3542) */
2021                                 u_char *optbuf;
2022                                 u_char optbuf_storage[MCLBYTES];
2023                                 int optlen;
2024                                 struct ip6_pktopts **optp;
2025
2026                                 /* cannot mix with RFC2292 */
2027                                 if (OPTBIT(IN6P_RFC2292)) {
2028                                         error = EINVAL;
2029                                         break;
2030                                 }
2031
2032                                 /*
2033                                  * We only ensure valsize is not too large
2034                                  * here.  Further validation will be done
2035                                  * later.
2036                                  */
2037                                 error = sooptcopyin(sopt, optbuf_storage,
2038                                     sizeof(optbuf_storage), 0);
2039                                 if (error)
2040                                         break;
2041                                 optlen = sopt->sopt_valsize;
2042                                 optbuf = optbuf_storage;
2043                                 INP_WLOCK(inp);
2044                                 if (inp->inp_flags & INP_DROPPED) {
2045                                         INP_WUNLOCK(inp);
2046                                         return (ECONNRESET);
2047                                 }
2048                                 optp = &inp->in6p_outputopts;
2049                                 error = ip6_pcbopt(optname, optbuf, optlen,
2050                                     optp, (td != NULL) ? td->td_ucred : NULL,
2051                                     uproto);
2052                                 INP_WUNLOCK(inp);
2053                                 break;
2054                         }
2055 #undef OPTSET
2056
2057                         case IPV6_MULTICAST_IF:
2058                         case IPV6_MULTICAST_HOPS:
2059                         case IPV6_MULTICAST_LOOP:
2060                         case IPV6_JOIN_GROUP:
2061                         case IPV6_LEAVE_GROUP:
2062                         case IPV6_MSFILTER:
2063                         case MCAST_BLOCK_SOURCE:
2064                         case MCAST_UNBLOCK_SOURCE:
2065                         case MCAST_JOIN_GROUP:
2066                         case MCAST_LEAVE_GROUP:
2067                         case MCAST_JOIN_SOURCE_GROUP:
2068                         case MCAST_LEAVE_SOURCE_GROUP:
2069                                 error = ip6_setmoptions(inp, sopt);
2070                                 break;
2071
2072                         case IPV6_PORTRANGE:
2073                                 error = sooptcopyin(sopt, &optval,
2074                                     sizeof optval, sizeof optval);
2075                                 if (error)
2076                                         break;
2077
2078                                 INP_WLOCK(inp);
2079                                 switch (optval) {
2080                                 case IPV6_PORTRANGE_DEFAULT:
2081                                         inp->inp_flags &= ~(INP_LOWPORT);
2082                                         inp->inp_flags &= ~(INP_HIGHPORT);
2083                                         break;
2084
2085                                 case IPV6_PORTRANGE_HIGH:
2086                                         inp->inp_flags &= ~(INP_LOWPORT);
2087                                         inp->inp_flags |= INP_HIGHPORT;
2088                                         break;
2089
2090                                 case IPV6_PORTRANGE_LOW:
2091                                         inp->inp_flags &= ~(INP_HIGHPORT);
2092                                         inp->inp_flags |= INP_LOWPORT;
2093                                         break;
2094
2095                                 default:
2096                                         error = EINVAL;
2097                                         break;
2098                                 }
2099                                 INP_WUNLOCK(inp);
2100                                 break;
2101
2102 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2103                         case IPV6_IPSEC_POLICY:
2104                                 if (IPSEC_ENABLED(ipv6)) {
2105                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2106                                         break;
2107                                 }
2108                                 /* FALLTHROUGH */
2109 #endif /* IPSEC */
2110
2111                         default:
2112                                 error = ENOPROTOOPT;
2113                                 break;
2114                         }
2115                         break;
2116
2117                 case SOPT_GET:
2118                         switch (optname) {
2119                         case IPV6_2292PKTOPTIONS:
2120 #ifdef IPV6_PKTOPTIONS
2121                         case IPV6_PKTOPTIONS:
2122 #endif
2123                                 /*
2124                                  * RFC3542 (effectively) deprecated the
2125                                  * semantics of the 2292-style pktoptions.
2126                                  * Since it was not reliable in nature (i.e.,
2127                                  * applications had to expect the lack of some
2128                                  * information after all), it would make sense
2129                                  * to simplify this part by always returning
2130                                  * empty data.
2131                                  */
2132                                 sopt->sopt_valsize = 0;
2133                                 break;
2134
2135                         case IPV6_RECVHOPOPTS:
2136                         case IPV6_RECVDSTOPTS:
2137                         case IPV6_RECVRTHDRDSTOPTS:
2138                         case IPV6_UNICAST_HOPS:
2139                         case IPV6_RECVPKTINFO:
2140                         case IPV6_RECVHOPLIMIT:
2141                         case IPV6_RECVRTHDR:
2142                         case IPV6_RECVPATHMTU:
2143
2144                         case IPV6_V6ONLY:
2145                         case IPV6_PORTRANGE:
2146                         case IPV6_RECVTCLASS:
2147                         case IPV6_AUTOFLOWLABEL:
2148                         case IPV6_BINDANY:
2149                         case IPV6_FLOWID:
2150                         case IPV6_FLOWTYPE:
2151                         case IPV6_RECVFLOWID:
2152 #ifdef  RSS
2153                         case IPV6_RSSBUCKETID:
2154                         case IPV6_RECVRSSBUCKETID:
2155 #endif
2156                         case IPV6_VLAN_PCP:
2157                                 switch (optname) {
2158                                 case IPV6_RECVHOPOPTS:
2159                                         optval = OPTBIT(IN6P_HOPOPTS);
2160                                         break;
2161
2162                                 case IPV6_RECVDSTOPTS:
2163                                         optval = OPTBIT(IN6P_DSTOPTS);
2164                                         break;
2165
2166                                 case IPV6_RECVRTHDRDSTOPTS:
2167                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2168                                         break;
2169
2170                                 case IPV6_UNICAST_HOPS:
2171                                         optval = inp->in6p_hops;
2172                                         break;
2173
2174                                 case IPV6_RECVPKTINFO:
2175                                         optval = OPTBIT(IN6P_PKTINFO);
2176                                         break;
2177
2178                                 case IPV6_RECVHOPLIMIT:
2179                                         optval = OPTBIT(IN6P_HOPLIMIT);
2180                                         break;
2181
2182                                 case IPV6_RECVRTHDR:
2183                                         optval = OPTBIT(IN6P_RTHDR);
2184                                         break;
2185
2186                                 case IPV6_RECVPATHMTU:
2187                                         optval = OPTBIT(IN6P_MTU);
2188                                         break;
2189
2190                                 case IPV6_V6ONLY:
2191                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2192                                         break;
2193
2194                                 case IPV6_PORTRANGE:
2195                                     {
2196                                         int flags;
2197                                         flags = inp->inp_flags;
2198                                         if (flags & INP_HIGHPORT)
2199                                                 optval = IPV6_PORTRANGE_HIGH;
2200                                         else if (flags & INP_LOWPORT)
2201                                                 optval = IPV6_PORTRANGE_LOW;
2202                                         else
2203                                                 optval = 0;
2204                                         break;
2205                                     }
2206                                 case IPV6_RECVTCLASS:
2207                                         optval = OPTBIT(IN6P_TCLASS);
2208                                         break;
2209
2210                                 case IPV6_AUTOFLOWLABEL:
2211                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2212                                         break;
2213
2214                                 case IPV6_ORIGDSTADDR:
2215                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2216                                         break;
2217
2218                                 case IPV6_BINDANY:
2219                                         optval = OPTBIT(INP_BINDANY);
2220                                         break;
2221
2222                                 case IPV6_FLOWID:
2223                                         optval = inp->inp_flowid;
2224                                         break;
2225
2226                                 case IPV6_FLOWTYPE:
2227                                         optval = inp->inp_flowtype;
2228                                         break;
2229
2230                                 case IPV6_RECVFLOWID:
2231                                         optval = OPTBIT2(INP_RECVFLOWID);
2232                                         break;
2233 #ifdef  RSS
2234                                 case IPV6_RSSBUCKETID:
2235                                         retval =
2236                                             rss_hash2bucket(inp->inp_flowid,
2237                                             inp->inp_flowtype,
2238                                             &rss_bucket);
2239                                         if (retval == 0)
2240                                                 optval = rss_bucket;
2241                                         else
2242                                                 error = EINVAL;
2243                                         break;
2244
2245                                 case IPV6_RECVRSSBUCKETID:
2246                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2247                                         break;
2248 #endif
2249
2250
2251                                 case IPV6_VLAN_PCP:
2252                                         if (OPTBIT2(INP_2PCP_SET)) {
2253                                                 optval = (inp->inp_flags2 &
2254                                                             INP_2PCP_MASK) >>
2255                                                             INP_2PCP_SHIFT;
2256                                         } else {
2257                                                 optval = -1;
2258                                         }
2259                                         break;
2260                                 }
2261
2262                                 if (error)
2263                                         break;
2264                                 error = sooptcopyout(sopt, &optval,
2265                                         sizeof optval);
2266                                 break;
2267
2268                         case IPV6_PATHMTU:
2269                         {
2270                                 u_long pmtu = 0;
2271                                 struct ip6_mtuinfo mtuinfo;
2272                                 struct in6_addr addr;
2273
2274                                 if (!(so->so_state & SS_ISCONNECTED))
2275                                         return (ENOTCONN);
2276                                 /*
2277                                  * XXX: we dot not consider the case of source
2278                                  * routing, or optional information to specify
2279                                  * the outgoing interface.
2280                                  * Copy faddr out of inp to avoid holding lock
2281                                  * on inp during route lookup.
2282                                  */
2283                                 INP_RLOCK(inp);
2284                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2285                                 INP_RUNLOCK(inp);
2286                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2287                                     &addr, &pmtu);
2288                                 if (error)
2289                                         break;
2290                                 if (pmtu > IPV6_MAXPACKET)
2291                                         pmtu = IPV6_MAXPACKET;
2292
2293                                 bzero(&mtuinfo, sizeof(mtuinfo));
2294                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2295                                 optdata = (void *)&mtuinfo;
2296                                 optdatalen = sizeof(mtuinfo);
2297                                 error = sooptcopyout(sopt, optdata,
2298                                     optdatalen);
2299                                 break;
2300                         }
2301
2302                         case IPV6_2292PKTINFO:
2303                         case IPV6_2292HOPLIMIT:
2304                         case IPV6_2292HOPOPTS:
2305                         case IPV6_2292RTHDR:
2306                         case IPV6_2292DSTOPTS:
2307                                 switch (optname) {
2308                                 case IPV6_2292PKTINFO:
2309                                         optval = OPTBIT(IN6P_PKTINFO);
2310                                         break;
2311                                 case IPV6_2292HOPLIMIT:
2312                                         optval = OPTBIT(IN6P_HOPLIMIT);
2313                                         break;
2314                                 case IPV6_2292HOPOPTS:
2315                                         optval = OPTBIT(IN6P_HOPOPTS);
2316                                         break;
2317                                 case IPV6_2292RTHDR:
2318                                         optval = OPTBIT(IN6P_RTHDR);
2319                                         break;
2320                                 case IPV6_2292DSTOPTS:
2321                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2322                                         break;
2323                                 }
2324                                 error = sooptcopyout(sopt, &optval,
2325                                     sizeof optval);
2326                                 break;
2327                         case IPV6_PKTINFO:
2328                         case IPV6_HOPOPTS:
2329                         case IPV6_RTHDR:
2330                         case IPV6_DSTOPTS:
2331                         case IPV6_RTHDRDSTOPTS:
2332                         case IPV6_NEXTHOP:
2333                         case IPV6_TCLASS:
2334                         case IPV6_DONTFRAG:
2335                         case IPV6_USE_MIN_MTU:
2336                         case IPV6_PREFER_TEMPADDR:
2337                                 error = ip6_getpcbopt(inp, optname, sopt);
2338                                 break;
2339
2340                         case IPV6_MULTICAST_IF:
2341                         case IPV6_MULTICAST_HOPS:
2342                         case IPV6_MULTICAST_LOOP:
2343                         case IPV6_MSFILTER:
2344                                 error = ip6_getmoptions(inp, sopt);
2345                                 break;
2346
2347 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2348                         case IPV6_IPSEC_POLICY:
2349                                 if (IPSEC_ENABLED(ipv6)) {
2350                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2351                                         break;
2352                                 }
2353                                 /* FALLTHROUGH */
2354 #endif /* IPSEC */
2355                         default:
2356                                 error = ENOPROTOOPT;
2357                                 break;
2358                         }
2359                         break;
2360                 }
2361         }
2362         return (error);
2363 }
2364
2365 int
2366 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2367 {
2368         int error = 0, optval, optlen;
2369         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2370         struct inpcb *inp = sotoinpcb(so);
2371         int level, op, optname;
2372
2373         level = sopt->sopt_level;
2374         op = sopt->sopt_dir;
2375         optname = sopt->sopt_name;
2376         optlen = sopt->sopt_valsize;
2377
2378         if (level != IPPROTO_IPV6) {
2379                 return (EINVAL);
2380         }
2381
2382         switch (optname) {
2383         case IPV6_CHECKSUM:
2384                 /*
2385                  * For ICMPv6 sockets, no modification allowed for checksum
2386                  * offset, permit "no change" values to help existing apps.
2387                  *
2388                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2389                  * for an ICMPv6 socket will fail."
2390                  * The current behavior does not meet RFC3542.
2391                  */
2392                 switch (op) {
2393                 case SOPT_SET:
2394                         if (optlen != sizeof(int)) {
2395                                 error = EINVAL;
2396                                 break;
2397                         }
2398                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2399                                             sizeof(optval));
2400                         if (error)
2401                                 break;
2402                         if (optval < -1 || (optval % 2) != 0) {
2403                                 /*
2404                                  * The API assumes non-negative even offset
2405                                  * values or -1 as a special value.
2406                                  */
2407                                 error = EINVAL;
2408                         } else if (inp->inp_ip_p == IPPROTO_ICMPV6) {
2409                                 if (optval != icmp6off)
2410                                         error = EINVAL;
2411                         } else
2412                                 inp->in6p_cksum = optval;
2413                         break;
2414
2415                 case SOPT_GET:
2416                         if (inp->inp_ip_p == IPPROTO_ICMPV6)
2417                                 optval = icmp6off;
2418                         else
2419                                 optval = inp->in6p_cksum;
2420
2421                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2422                         break;
2423
2424                 default:
2425                         error = EINVAL;
2426                         break;
2427                 }
2428                 break;
2429
2430         default:
2431                 error = ENOPROTOOPT;
2432                 break;
2433         }
2434
2435         return (error);
2436 }
2437
2438 /*
2439  * Set up IP6 options in pcb for insertion in output packets or
2440  * specifying behavior of outgoing packets.
2441  */
2442 static int
2443 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2444     struct socket *so, struct sockopt *sopt)
2445 {
2446         struct ip6_pktopts *opt = *pktopt;
2447         int error = 0;
2448         struct thread *td = sopt->sopt_td;
2449         struct epoch_tracker et;
2450
2451         /* turn off any old options. */
2452         if (opt) {
2453 #ifdef DIAGNOSTIC
2454                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2455                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2456                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2457                         printf("ip6_pcbopts: all specified options are cleared.\n");
2458 #endif
2459                 ip6_clearpktopts(opt, -1);
2460         } else {
2461                 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT);
2462                 if (opt == NULL)
2463                         return (ENOMEM);
2464         }
2465         *pktopt = NULL;
2466
2467         if (!m || m->m_len == 0) {
2468                 /*
2469                  * Only turning off any previous options, regardless of
2470                  * whether the opt is just created or given.
2471                  */
2472                 free(opt, M_IP6OPT);
2473                 return (0);
2474         }
2475
2476         /*  set options specified by user. */
2477         NET_EPOCH_ENTER(et);
2478         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2479             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2480                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2481                 free(opt, M_IP6OPT);
2482                 NET_EPOCH_EXIT(et);
2483                 return (error);
2484         }
2485         NET_EPOCH_EXIT(et);
2486         *pktopt = opt;
2487         return (0);
2488 }
2489
2490 /*
2491  * initialize ip6_pktopts.  beware that there are non-zero default values in
2492  * the struct.
2493  */
2494 void
2495 ip6_initpktopts(struct ip6_pktopts *opt)
2496 {
2497
2498         bzero(opt, sizeof(*opt));
2499         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2500         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2501         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2502         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2503 }
2504
2505 static int
2506 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2507     struct ucred *cred, int uproto)
2508 {
2509         struct epoch_tracker et;
2510         struct ip6_pktopts *opt;
2511         int ret;
2512
2513         if (*pktopt == NULL) {
2514                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2515                     M_NOWAIT);
2516                 if (*pktopt == NULL)
2517                         return (ENOBUFS);
2518                 ip6_initpktopts(*pktopt);
2519         }
2520         opt = *pktopt;
2521
2522         NET_EPOCH_ENTER(et);
2523         ret = ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto);
2524         NET_EPOCH_EXIT(et);
2525
2526         return (ret);
2527 }
2528
2529 #define GET_PKTOPT_VAR(field, lenexpr) do {                             \
2530         if (pktopt && pktopt->field) {                                  \
2531                 INP_RUNLOCK(inp);                                       \
2532                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK); \
2533                 malloc_optdata = true;                                  \
2534                 INP_RLOCK(inp);                                         \
2535                 if (inp->inp_flags & INP_DROPPED) {                     \
2536                         INP_RUNLOCK(inp);                               \
2537                         free(optdata, M_TEMP);                          \
2538                         return (ECONNRESET);                            \
2539                 }                                                       \
2540                 pktopt = inp->in6p_outputopts;                          \
2541                 if (pktopt && pktopt->field) {                          \
2542                         optdatalen = min(lenexpr, sopt->sopt_valsize);  \
2543                         bcopy(pktopt->field, optdata, optdatalen);      \
2544                 } else {                                                \
2545                         free(optdata, M_TEMP);                          \
2546                         optdata = NULL;                                 \
2547                         malloc_optdata = false;                         \
2548                 }                                                       \
2549         }                                                               \
2550 } while(0)
2551
2552 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                 \
2553         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2554
2555 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                \
2556         pktopt->field->sa_len)
2557
2558 static int
2559 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2560 {
2561         void *optdata = NULL;
2562         bool malloc_optdata = false;
2563         int optdatalen = 0;
2564         int error = 0;
2565         struct in6_pktinfo null_pktinfo;
2566         int deftclass = 0, on;
2567         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2568         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2569         struct ip6_pktopts *pktopt;
2570
2571         INP_RLOCK(inp);
2572         pktopt = inp->in6p_outputopts;
2573
2574         switch (optname) {
2575         case IPV6_PKTINFO:
2576                 optdata = (void *)&null_pktinfo;
2577                 if (pktopt && pktopt->ip6po_pktinfo) {
2578                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2579                             sizeof(null_pktinfo));
2580                         in6_clearscope(&null_pktinfo.ipi6_addr);
2581                 } else {
2582                         /* XXX: we don't have to do this every time... */
2583                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2584                 }
2585                 optdatalen = sizeof(struct in6_pktinfo);
2586                 break;
2587         case IPV6_TCLASS:
2588                 if (pktopt && pktopt->ip6po_tclass >= 0)
2589                         deftclass = pktopt->ip6po_tclass;
2590                 optdata = (void *)&deftclass;
2591                 optdatalen = sizeof(int);
2592                 break;
2593         case IPV6_HOPOPTS:
2594                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2595                 break;
2596         case IPV6_RTHDR:
2597                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2598                 break;
2599         case IPV6_RTHDRDSTOPTS:
2600                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2601                 break;
2602         case IPV6_DSTOPTS:
2603                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2604                 break;
2605         case IPV6_NEXTHOP:
2606                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2607                 break;
2608         case IPV6_USE_MIN_MTU:
2609                 if (pktopt)
2610                         defminmtu = pktopt->ip6po_minmtu;
2611                 optdata = (void *)&defminmtu;
2612                 optdatalen = sizeof(int);
2613                 break;
2614         case IPV6_DONTFRAG:
2615                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2616                         on = 1;
2617                 else
2618                         on = 0;
2619                 optdata = (void *)&on;
2620                 optdatalen = sizeof(on);
2621                 break;
2622         case IPV6_PREFER_TEMPADDR:
2623                 if (pktopt)
2624                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2625                 optdata = (void *)&defpreftemp;
2626                 optdatalen = sizeof(int);
2627                 break;
2628         default:                /* should not happen */
2629 #ifdef DIAGNOSTIC
2630                 panic("ip6_getpcbopt: unexpected option\n");
2631 #endif
2632                 INP_RUNLOCK(inp);
2633                 return (ENOPROTOOPT);
2634         }
2635         INP_RUNLOCK(inp);
2636
2637         error = sooptcopyout(sopt, optdata, optdatalen);
2638         if (malloc_optdata)
2639                 free(optdata, M_TEMP);
2640
2641         return (error);
2642 }
2643
2644 void
2645 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2646 {
2647         if (pktopt == NULL)
2648                 return;
2649
2650         if (optname == -1 || optname == IPV6_PKTINFO) {
2651                 if (pktopt->ip6po_pktinfo)
2652                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2653                 pktopt->ip6po_pktinfo = NULL;
2654         }
2655         if (optname == -1 || optname == IPV6_HOPLIMIT)
2656                 pktopt->ip6po_hlim = -1;
2657         if (optname == -1 || optname == IPV6_TCLASS)
2658                 pktopt->ip6po_tclass = -1;
2659         if (optname == -1 || optname == IPV6_NEXTHOP) {
2660                 if (pktopt->ip6po_nextroute.ro_nh) {
2661                         NH_FREE(pktopt->ip6po_nextroute.ro_nh);
2662                         pktopt->ip6po_nextroute.ro_nh = NULL;
2663                 }
2664                 if (pktopt->ip6po_nexthop)
2665                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2666                 pktopt->ip6po_nexthop = NULL;
2667         }
2668         if (optname == -1 || optname == IPV6_HOPOPTS) {
2669                 if (pktopt->ip6po_hbh)
2670                         free(pktopt->ip6po_hbh, M_IP6OPT);
2671                 pktopt->ip6po_hbh = NULL;
2672         }
2673         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2674                 if (pktopt->ip6po_dest1)
2675                         free(pktopt->ip6po_dest1, M_IP6OPT);
2676                 pktopt->ip6po_dest1 = NULL;
2677         }
2678         if (optname == -1 || optname == IPV6_RTHDR) {
2679                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2680                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2681                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2682                 if (pktopt->ip6po_route.ro_nh) {
2683                         NH_FREE(pktopt->ip6po_route.ro_nh);
2684                         pktopt->ip6po_route.ro_nh = NULL;
2685                 }
2686         }
2687         if (optname == -1 || optname == IPV6_DSTOPTS) {
2688                 if (pktopt->ip6po_dest2)
2689                         free(pktopt->ip6po_dest2, M_IP6OPT);
2690                 pktopt->ip6po_dest2 = NULL;
2691         }
2692 }
2693
2694 #define PKTOPT_EXTHDRCPY(type) \
2695 do {\
2696         if (src->type) {\
2697                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2698                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2699                 if (dst->type == NULL)\
2700                         goto bad;\
2701                 bcopy(src->type, dst->type, hlen);\
2702         }\
2703 } while (/*CONSTCOND*/ 0)
2704
2705 static int
2706 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2707 {
2708         if (dst == NULL || src == NULL)  {
2709                 printf("ip6_clearpktopts: invalid argument\n");
2710                 return (EINVAL);
2711         }
2712
2713         dst->ip6po_hlim = src->ip6po_hlim;
2714         dst->ip6po_tclass = src->ip6po_tclass;
2715         dst->ip6po_flags = src->ip6po_flags;
2716         dst->ip6po_minmtu = src->ip6po_minmtu;
2717         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2718         if (src->ip6po_pktinfo) {
2719                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2720                     M_IP6OPT, canwait);
2721                 if (dst->ip6po_pktinfo == NULL)
2722                         goto bad;
2723                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2724         }
2725         if (src->ip6po_nexthop) {
2726                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2727                     M_IP6OPT, canwait);
2728                 if (dst->ip6po_nexthop == NULL)
2729                         goto bad;
2730                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2731                     src->ip6po_nexthop->sa_len);
2732         }
2733         PKTOPT_EXTHDRCPY(ip6po_hbh);
2734         PKTOPT_EXTHDRCPY(ip6po_dest1);
2735         PKTOPT_EXTHDRCPY(ip6po_dest2);
2736         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2737         return (0);
2738
2739   bad:
2740         ip6_clearpktopts(dst, -1);
2741         return (ENOBUFS);
2742 }
2743 #undef PKTOPT_EXTHDRCPY
2744
2745 struct ip6_pktopts *
2746 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2747 {
2748         int error;
2749         struct ip6_pktopts *dst;
2750
2751         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2752         if (dst == NULL)
2753                 return (NULL);
2754         ip6_initpktopts(dst);
2755
2756         if ((error = copypktopts(dst, src, canwait)) != 0) {
2757                 free(dst, M_IP6OPT);
2758                 return (NULL);
2759         }
2760
2761         return (dst);
2762 }
2763
2764 void
2765 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2766 {
2767         if (pktopt == NULL)
2768                 return;
2769
2770         ip6_clearpktopts(pktopt, -1);
2771
2772         free(pktopt, M_IP6OPT);
2773 }
2774
2775 /*
2776  * Set IPv6 outgoing packet options based on advanced API.
2777  */
2778 int
2779 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2780     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2781 {
2782         struct cmsghdr *cm = NULL;
2783
2784         if (control == NULL || opt == NULL)
2785                 return (EINVAL);
2786
2787         /*
2788          * ip6_setpktopt can call ifnet_byindex(), so it's imperative that we
2789          * are in the network epoch here.
2790          */
2791         NET_EPOCH_ASSERT();
2792
2793         ip6_initpktopts(opt);
2794         if (stickyopt) {
2795                 int error;
2796
2797                 /*
2798                  * If stickyopt is provided, make a local copy of the options
2799                  * for this particular packet, then override them by ancillary
2800                  * objects.
2801                  * XXX: copypktopts() does not copy the cached route to a next
2802                  * hop (if any).  This is not very good in terms of efficiency,
2803                  * but we can allow this since this option should be rarely
2804                  * used.
2805                  */
2806                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2807                         return (error);
2808         }
2809
2810         /*
2811          * XXX: Currently, we assume all the optional information is stored
2812          * in a single mbuf.
2813          */
2814         if (control->m_next)
2815                 return (EINVAL);
2816
2817         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2818             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2819                 int error;
2820
2821                 if (control->m_len < CMSG_LEN(0))
2822                         return (EINVAL);
2823
2824                 cm = mtod(control, struct cmsghdr *);
2825                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2826                         return (EINVAL);
2827                 if (cm->cmsg_level != IPPROTO_IPV6)
2828                         continue;
2829
2830                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2831                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2832                 if (error)
2833                         return (error);
2834         }
2835
2836         return (0);
2837 }
2838
2839 /*
2840  * Set a particular packet option, as a sticky option or an ancillary data
2841  * item.  "len" can be 0 only when it's a sticky option.
2842  * We have 4 cases of combination of "sticky" and "cmsg":
2843  * "sticky=0, cmsg=0": impossible
2844  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2845  * "sticky=1, cmsg=0": RFC3542 socket option
2846  * "sticky=1, cmsg=1": RFC2292 socket option
2847  */
2848 static int
2849 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2850     struct ucred *cred, int sticky, int cmsg, int uproto)
2851 {
2852         int minmtupolicy, preftemp;
2853         int error;
2854
2855         NET_EPOCH_ASSERT();
2856
2857         if (!sticky && !cmsg) {
2858 #ifdef DIAGNOSTIC
2859                 printf("ip6_setpktopt: impossible case\n");
2860 #endif
2861                 return (EINVAL);
2862         }
2863
2864         /*
2865          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2866          * not be specified in the context of RFC3542.  Conversely,
2867          * RFC3542 types should not be specified in the context of RFC2292.
2868          */
2869         if (!cmsg) {
2870                 switch (optname) {
2871                 case IPV6_2292PKTINFO:
2872                 case IPV6_2292HOPLIMIT:
2873                 case IPV6_2292NEXTHOP:
2874                 case IPV6_2292HOPOPTS:
2875                 case IPV6_2292DSTOPTS:
2876                 case IPV6_2292RTHDR:
2877                 case IPV6_2292PKTOPTIONS:
2878                         return (ENOPROTOOPT);
2879                 }
2880         }
2881         if (sticky && cmsg) {
2882                 switch (optname) {
2883                 case IPV6_PKTINFO:
2884                 case IPV6_HOPLIMIT:
2885                 case IPV6_NEXTHOP:
2886                 case IPV6_HOPOPTS:
2887                 case IPV6_DSTOPTS:
2888                 case IPV6_RTHDRDSTOPTS:
2889                 case IPV6_RTHDR:
2890                 case IPV6_USE_MIN_MTU:
2891                 case IPV6_DONTFRAG:
2892                 case IPV6_TCLASS:
2893                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2894                         return (ENOPROTOOPT);
2895                 }
2896         }
2897
2898         switch (optname) {
2899         case IPV6_2292PKTINFO:
2900         case IPV6_PKTINFO:
2901         {
2902                 struct ifnet *ifp = NULL;
2903                 struct in6_pktinfo *pktinfo;
2904
2905                 if (len != sizeof(struct in6_pktinfo))
2906                         return (EINVAL);
2907
2908                 pktinfo = (struct in6_pktinfo *)buf;
2909
2910                 /*
2911                  * An application can clear any sticky IPV6_PKTINFO option by
2912                  * doing a "regular" setsockopt with ipi6_addr being
2913                  * in6addr_any and ipi6_ifindex being zero.
2914                  * [RFC 3542, Section 6]
2915                  */
2916                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2917                     pktinfo->ipi6_ifindex == 0 &&
2918                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2919                         ip6_clearpktopts(opt, optname);
2920                         break;
2921                 }
2922
2923                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2924                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2925                         return (EINVAL);
2926                 }
2927                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2928                         return (EINVAL);
2929                 /* validate the interface index if specified. */
2930                 if (pktinfo->ipi6_ifindex) {
2931                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2932                         if (ifp == NULL)
2933                                 return (ENXIO);
2934                 }
2935                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2936                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2937                         return (ENETDOWN);
2938
2939                 if (ifp != NULL &&
2940                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2941                         struct in6_ifaddr *ia;
2942
2943                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2944                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2945                         if (ia == NULL)
2946                                 return (EADDRNOTAVAIL);
2947                         ifa_free(&ia->ia_ifa);
2948                 }
2949                 /*
2950                  * We store the address anyway, and let in6_selectsrc()
2951                  * validate the specified address.  This is because ipi6_addr
2952                  * may not have enough information about its scope zone, and
2953                  * we may need additional information (such as outgoing
2954                  * interface or the scope zone of a destination address) to
2955                  * disambiguate the scope.
2956                  * XXX: the delay of the validation may confuse the
2957                  * application when it is used as a sticky option.
2958                  */
2959                 if (opt->ip6po_pktinfo == NULL) {
2960                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2961                             M_IP6OPT, M_NOWAIT);
2962                         if (opt->ip6po_pktinfo == NULL)
2963                                 return (ENOBUFS);
2964                 }
2965                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2966                 break;
2967         }
2968
2969         case IPV6_2292HOPLIMIT:
2970         case IPV6_HOPLIMIT:
2971         {
2972                 int *hlimp;
2973
2974                 /*
2975                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2976                  * to simplify the ordering among hoplimit options.
2977                  */
2978                 if (optname == IPV6_HOPLIMIT && sticky)
2979                         return (ENOPROTOOPT);
2980
2981                 if (len != sizeof(int))
2982                         return (EINVAL);
2983                 hlimp = (int *)buf;
2984                 if (*hlimp < -1 || *hlimp > 255)
2985                         return (EINVAL);
2986
2987                 opt->ip6po_hlim = *hlimp;
2988                 break;
2989         }
2990
2991         case IPV6_TCLASS:
2992         {
2993                 int tclass;
2994
2995                 if (len != sizeof(int))
2996                         return (EINVAL);
2997                 tclass = *(int *)buf;
2998                 if (tclass < -1 || tclass > 255)
2999                         return (EINVAL);
3000
3001                 opt->ip6po_tclass = tclass;
3002                 break;
3003         }
3004
3005         case IPV6_2292NEXTHOP:
3006         case IPV6_NEXTHOP:
3007                 if (cred != NULL) {
3008                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3009                         if (error)
3010                                 return (error);
3011                 }
3012
3013                 if (len == 0) { /* just remove the option */
3014                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
3015                         break;
3016                 }
3017
3018                 /* check if cmsg_len is large enough for sa_len */
3019                 if (len < sizeof(struct sockaddr) || len < *buf)
3020                         return (EINVAL);
3021
3022                 switch (((struct sockaddr *)buf)->sa_family) {
3023                 case AF_INET6:
3024                 {
3025                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
3026                         int error;
3027
3028                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
3029                                 return (EINVAL);
3030
3031                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
3032                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
3033                                 return (EINVAL);
3034                         }
3035                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
3036                             != 0) {
3037                                 return (error);
3038                         }
3039                         break;
3040                 }
3041                 case AF_LINK:   /* should eventually be supported */
3042                 default:
3043                         return (EAFNOSUPPORT);
3044                 }
3045
3046                 /* turn off the previous option, then set the new option. */
3047                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
3048                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
3049                 if (opt->ip6po_nexthop == NULL)
3050                         return (ENOBUFS);
3051                 bcopy(buf, opt->ip6po_nexthop, *buf);
3052                 break;
3053
3054         case IPV6_2292HOPOPTS:
3055         case IPV6_HOPOPTS:
3056         {
3057                 struct ip6_hbh *hbh;
3058                 int hbhlen;
3059
3060                 /*
3061                  * XXX: We don't allow a non-privileged user to set ANY HbH
3062                  * options, since per-option restriction has too much
3063                  * overhead.
3064                  */
3065                 if (cred != NULL) {
3066                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3067                         if (error)
3068                                 return (error);
3069                 }
3070
3071                 if (len == 0) {
3072                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
3073                         break;  /* just remove the option */
3074                 }
3075
3076                 /* message length validation */
3077                 if (len < sizeof(struct ip6_hbh))
3078                         return (EINVAL);
3079                 hbh = (struct ip6_hbh *)buf;
3080                 hbhlen = (hbh->ip6h_len + 1) << 3;
3081                 if (len != hbhlen)
3082                         return (EINVAL);
3083
3084                 /* turn off the previous option, then set the new option. */
3085                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
3086                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
3087                 if (opt->ip6po_hbh == NULL)
3088                         return (ENOBUFS);
3089                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
3090
3091                 break;
3092         }
3093
3094         case IPV6_2292DSTOPTS:
3095         case IPV6_DSTOPTS:
3096         case IPV6_RTHDRDSTOPTS:
3097         {
3098                 struct ip6_dest *dest, **newdest = NULL;
3099                 int destlen;
3100
3101                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
3102                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3103                         if (error)
3104                                 return (error);
3105                 }
3106
3107                 if (len == 0) {
3108                         ip6_clearpktopts(opt, optname);
3109                         break;  /* just remove the option */
3110                 }
3111
3112                 /* message length validation */
3113                 if (len < sizeof(struct ip6_dest))
3114                         return (EINVAL);
3115                 dest = (struct ip6_dest *)buf;
3116                 destlen = (dest->ip6d_len + 1) << 3;
3117                 if (len != destlen)
3118                         return (EINVAL);
3119
3120                 /*
3121                  * Determine the position that the destination options header
3122                  * should be inserted; before or after the routing header.
3123                  */
3124                 switch (optname) {
3125                 case IPV6_2292DSTOPTS:
3126                         /*
3127                          * The old advacned API is ambiguous on this point.
3128                          * Our approach is to determine the position based
3129                          * according to the existence of a routing header.
3130                          * Note, however, that this depends on the order of the
3131                          * extension headers in the ancillary data; the 1st
3132                          * part of the destination options header must appear
3133                          * before the routing header in the ancillary data,
3134                          * too.
3135                          * RFC3542 solved the ambiguity by introducing
3136                          * separate ancillary data or option types.
3137                          */
3138                         if (opt->ip6po_rthdr == NULL)
3139                                 newdest = &opt->ip6po_dest1;
3140                         else
3141                                 newdest = &opt->ip6po_dest2;
3142                         break;
3143                 case IPV6_RTHDRDSTOPTS:
3144                         newdest = &opt->ip6po_dest1;
3145                         break;
3146                 case IPV6_DSTOPTS:
3147                         newdest = &opt->ip6po_dest2;
3148                         break;
3149                 }
3150
3151                 /* turn off the previous option, then set the new option. */
3152                 ip6_clearpktopts(opt, optname);
3153                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3154                 if (*newdest == NULL)
3155                         return (ENOBUFS);
3156                 bcopy(dest, *newdest, destlen);
3157
3158                 break;
3159         }
3160
3161         case IPV6_2292RTHDR:
3162         case IPV6_RTHDR:
3163         {
3164                 struct ip6_rthdr *rth;
3165                 int rthlen;
3166
3167                 if (len == 0) {
3168                         ip6_clearpktopts(opt, IPV6_RTHDR);
3169                         break;  /* just remove the option */
3170                 }
3171
3172                 /* message length validation */
3173                 if (len < sizeof(struct ip6_rthdr))
3174                         return (EINVAL);
3175                 rth = (struct ip6_rthdr *)buf;
3176                 rthlen = (rth->ip6r_len + 1) << 3;
3177                 if (len != rthlen)
3178                         return (EINVAL);
3179
3180                 switch (rth->ip6r_type) {
3181                 case IPV6_RTHDR_TYPE_0:
3182                         if (rth->ip6r_len == 0) /* must contain one addr */
3183                                 return (EINVAL);
3184                         if (rth->ip6r_len % 2) /* length must be even */
3185                                 return (EINVAL);
3186                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3187                                 return (EINVAL);
3188                         break;
3189                 default:
3190                         return (EINVAL);        /* not supported */
3191                 }
3192
3193                 /* turn off the previous option */
3194                 ip6_clearpktopts(opt, IPV6_RTHDR);
3195                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3196                 if (opt->ip6po_rthdr == NULL)
3197                         return (ENOBUFS);
3198                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3199
3200                 break;
3201         }
3202
3203         case IPV6_USE_MIN_MTU:
3204                 if (len != sizeof(int))
3205                         return (EINVAL);
3206                 minmtupolicy = *(int *)buf;
3207                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3208                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3209                     minmtupolicy != IP6PO_MINMTU_ALL) {
3210                         return (EINVAL);
3211                 }
3212                 opt->ip6po_minmtu = minmtupolicy;
3213                 break;
3214
3215         case IPV6_DONTFRAG:
3216                 if (len != sizeof(int))
3217                         return (EINVAL);
3218
3219                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3220                         /*
3221                          * we ignore this option for TCP sockets.
3222                          * (RFC3542 leaves this case unspecified.)
3223                          */
3224                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3225                 } else
3226                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3227                 break;
3228
3229         case IPV6_PREFER_TEMPADDR:
3230                 if (len != sizeof(int))
3231                         return (EINVAL);
3232                 preftemp = *(int *)buf;
3233                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3234                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3235                     preftemp != IP6PO_TEMPADDR_PREFER) {
3236                         return (EINVAL);
3237                 }
3238                 opt->ip6po_prefer_tempaddr = preftemp;
3239                 break;
3240
3241         default:
3242                 return (ENOPROTOOPT);
3243         } /* end of switch */
3244
3245         return (0);
3246 }
3247
3248 /*
3249  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3250  * packet to the input queue of a specified interface.  Note that this
3251  * calls the output routine of the loopback "driver", but with an interface
3252  * pointer that might NOT be &loif -- easier than replicating that code here.
3253  */
3254 void
3255 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3256 {
3257         struct mbuf *copym;
3258         struct ip6_hdr *ip6;
3259
3260         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3261         if (copym == NULL)
3262                 return;
3263
3264         /*
3265          * Make sure to deep-copy IPv6 header portion in case the data
3266          * is in an mbuf cluster, so that we can safely override the IPv6
3267          * header portion later.
3268          */
3269         if (!M_WRITABLE(copym) ||
3270             copym->m_len < sizeof(struct ip6_hdr)) {
3271                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3272                 if (copym == NULL)
3273                         return;
3274         }
3275         ip6 = mtod(copym, struct ip6_hdr *);
3276         /*
3277          * clear embedded scope identifiers if necessary.
3278          * in6_clearscope will touch the addresses only when necessary.
3279          */
3280         in6_clearscope(&ip6->ip6_src);
3281         in6_clearscope(&ip6->ip6_dst);
3282         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3283                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3284                     CSUM_PSEUDO_HDR;
3285                 copym->m_pkthdr.csum_data = 0xffff;
3286         }
3287         if_simloop(ifp, copym, AF_INET6, 0);
3288 }
3289
3290 /*
3291  * Chop IPv6 header off from the payload.
3292  */
3293 static int
3294 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3295 {
3296         struct mbuf *mh;
3297         struct ip6_hdr *ip6;
3298
3299         ip6 = mtod(m, struct ip6_hdr *);
3300         if (m->m_len > sizeof(*ip6)) {
3301                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3302                 if (mh == NULL) {
3303                         m_freem(m);
3304                         return ENOBUFS;
3305                 }
3306                 m_move_pkthdr(mh, m);
3307                 M_ALIGN(mh, sizeof(*ip6));
3308                 m->m_len -= sizeof(*ip6);
3309                 m->m_data += sizeof(*ip6);
3310                 mh->m_next = m;
3311                 m = mh;
3312                 m->m_len = sizeof(*ip6);
3313                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3314         }
3315         exthdrs->ip6e_ip6 = m;
3316         return 0;
3317 }
3318
3319 /*
3320  * Compute IPv6 extension header length.
3321  */
3322 int
3323 ip6_optlen(struct inpcb *inp)
3324 {
3325         int len;
3326
3327         if (!inp->in6p_outputopts)
3328                 return 0;
3329
3330         len = 0;
3331 #define elen(x) \
3332     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3333
3334         len += elen(inp->in6p_outputopts->ip6po_hbh);
3335         if (inp->in6p_outputopts->ip6po_rthdr)
3336                 /* dest1 is valid with rthdr only */
3337                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3338         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3339         len += elen(inp->in6p_outputopts->ip6po_dest2);
3340         return len;
3341 #undef elen
3342 }