sys/netinet6/ip6_output.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the project nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $
  32  */
  33
  34 /*-
  35  * Copyright (c) 1982, 1986, 1988, 1990, 1993
  36  *      The Regents of the University of California.  All rights reserved.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 3. Neither the name of the University nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  60  * SUCH DAMAGE.
  61  *
  62  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  63  */
  64
  65 #include <sys/cdefs.h>
  66 __FBSDID("$FreeBSD$");
  67
  68 #include "opt_inet.h"
  69 #include "opt_inet6.h"
  70 #include "opt_ipsec.h"
  71 #include "opt_kern_tls.h"
  72 #include "opt_ratelimit.h"
  73 #include "opt_route.h"
  74 #include "opt_rss.h"
  75 #include "opt_sctp.h"
  76
  77 #include <sys/param.h>
  78 #include <sys/kernel.h>
  79 #include <sys/ktls.h>
  80 #include <sys/malloc.h>
  81 #include <sys/mbuf.h>
  82 #include <sys/errno.h>
  83 #include <sys/priv.h>
  84 #include <sys/proc.h>
  85 #include <sys/protosw.h>
  86 #include <sys/socket.h>
  87 #include <sys/socketvar.h>
  88 #include <sys/syslog.h>
  89 #include <sys/ucred.h>
  90
  91 #include <machine/in_cksum.h>
  92
  93 #include <net/if.h>
  94 #include <net/if_var.h>
  95 #include <net/if_vlan_var.h>
  96 #include <net/if_llatbl.h>
  97 #include <net/ethernet.h>
  98 #include <net/netisr.h>
  99 #include <net/route.h>
 100 #include <net/route/nhop.h>
 101 #include <net/pfil.h>
 102 #include <net/rss_config.h>
 103 #include <net/vnet.h>
 104
 105 #include <netinet/in.h>
 106 #include <netinet/in_var.h>
 107 #include <netinet/ip_var.h>
 108 #include <netinet6/in6_fib.h>
 109 #include <netinet6/in6_var.h>
 110 #include <netinet/ip6.h>
 111 #include <netinet/icmp6.h>
 112 #include <netinet6/ip6_var.h>
 113 #include <netinet/in_pcb.h>
 114 #include <netinet/tcp_var.h>
 115 #include <netinet6/nd6.h>
 116 #include <netinet6/in6_rss.h>
 117
 118 #include <netipsec/ipsec_support.h>
 119 #if defined(SCTP) || defined(SCTP_SUPPORT)
 120 #include <netinet/sctp.h>
 121 #include <netinet/sctp_crc32.h>
 122 #endif
 123
 124 #include <netinet6/ip6protosw.h>
 125 #include <netinet6/scope6_var.h>
 126
 127 extern int in6_mcast_loop;
 128
 129 struct ip6_exthdrs {
 130         struct mbuf *ip6e_ip6;
 131         struct mbuf *ip6e_hbh;
 132         struct mbuf *ip6e_dest1;
 133         struct mbuf *ip6e_rthdr;
 134         struct mbuf *ip6e_dest2;
 135 };
 136
 137 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 138
 139 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 140                            struct ucred *, int);
 141 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 142         struct socket *, struct sockopt *);
 143 static int ip6_getpcbopt(struct inpcb *, int, struct sockopt *);
 144 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 145         struct ucred *, int, int, int);
 146
 147 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 148 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 149         struct ip6_frag **);
 150 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 151 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 152 static int ip6_getpmtu(struct route_in6 *, int,
 153         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int,
 154         u_int);
 155 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 156         u_long *, int *, u_int);
 157 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 158 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 159
 160 /*
 161  * Make an extension header from option data.  hp is the source,
 162  * mp is the destination, and _ol is the optlen.
 163  */
 164 #define MAKE_EXTHDR(hp, mp, _ol)                                        \
 165     do {                                                                \
 166         if (hp) {                                                       \
 167                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 168                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 169                     ((eh)->ip6e_len + 1) << 3);                         \
 170                 if (error)                                              \
 171                         goto freehdrs;                                  \
 172                 (_ol) += (*(mp))->m_len;                                \
 173         }                                                               \
 174     } while (/*CONSTCOND*/ 0)
 175
 176 /*
 177  * Form a chain of extension headers.
 178  * m is the extension header mbuf
 179  * mp is the previous mbuf in the chain
 180  * p is the next header
 181  * i is the type of option.
 182  */
 183 #define MAKE_CHAIN(m, mp, p, i)\
 184     do {\
 185         if (m) {\
 186                 if (!hdrsplit) \
 187                         panic("%s:%d: assumption failed: "\
 188                             "hdr not split: hdrsplit %d exthdrs %p",\
 189                             __func__, __LINE__, hdrsplit, &exthdrs);\
 190                 *mtod((m), u_char *) = *(p);\
 191                 *(p) = (i);\
 192                 p = mtod((m), u_char *);\
 193                 (m)->m_next = (mp)->m_next;\
 194                 (mp)->m_next = (m);\
 195                 (mp) = (m);\
 196         }\
 197     } while (/*CONSTCOND*/ 0)
 198
 199 void
 200 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 201 {
 202         u_short csum;
 203
 204         csum = in_cksum_skip(m, offset + plen, offset);
 205         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 206                 csum = 0xffff;
 207         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 208
 209         if (offset + sizeof(csum) > m->m_len)
 210                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
 211         else
 212                 *(u_short *)mtodo(m, offset) = csum;
 213 }
 214
 215 static int
 216 ip6_output_delayed_csum(struct mbuf *m, struct ifnet *ifp, int csum_flags,
 217     int plen, int optlen, bool frag)
 218 {
 219
 220         KASSERT((plen >= optlen), ("%s:%d: plen %d < optlen %d, m %p, ifp %p "
 221             "csum_flags %#x frag %d\n",
 222             __func__, __LINE__, plen, optlen, m, ifp, csum_flags, frag));
 223
 224         if ((csum_flags & CSUM_DELAY_DATA_IPV6) ||
 225 #if defined(SCTP) || defined(SCTP_SUPPORT)
 226             (csum_flags & CSUM_SCTP_IPV6) ||
 227 #endif
 228             (!frag && (ifp->if_capenable & IFCAP_NOMAP) == 0)) {
 229                 m = mb_unmapped_to_ext(m);
 230                 if (m == NULL) {
 231                         if (frag)
 232                                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 233                         else
 234                                 IP6STAT_INC(ip6s_odropped);
 235                         return (ENOBUFS);
 236                 }
 237                 if (csum_flags & CSUM_DELAY_DATA_IPV6) {
 238                         in6_delayed_cksum(m, plen - optlen,
 239                             sizeof(struct ip6_hdr) + optlen);
 240                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 241                 }
 242 #if defined(SCTP) || defined(SCTP_SUPPORT)
 243                 if (csum_flags & CSUM_SCTP_IPV6) {
 244                         sctp_delayed_cksum(m, sizeof(struct ip6_hdr) + optlen);
 245                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 246                 }
 247 #endif
 248         }
 249
 250         return (0);
 251 }
 252
 253 int
 254 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 255     int fraglen , uint32_t id)
 256 {
 257         struct mbuf *m, **mnext, *m_frgpart;
 258         struct ip6_hdr *ip6, *mhip6;
 259         struct ip6_frag *ip6f;
 260         int off;
 261         int error;
 262         int tlen = m0->m_pkthdr.len;
 263
 264         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 265
 266         m = m0;
 267         ip6 = mtod(m, struct ip6_hdr *);
 268         mnext = &m->m_nextpkt;
 269
 270         for (off = hlen; off < tlen; off += fraglen) {
 271                 m = m_gethdr(M_NOWAIT, MT_DATA);
 272                 if (!m) {
 273                         IP6STAT_INC(ip6s_odropped);
 274                         return (ENOBUFS);
 275                 }
 276
 277                 /*
 278                  * Make sure the complete packet header gets copied
 279                  * from the originating mbuf to the newly created
 280                  * mbuf. This also ensures that existing firewall
 281                  * classification(s), VLAN tags and so on get copied
 282                  * to the resulting fragmented packet(s):
 283                  */
 284                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 285                         m_free(m);
 286                         IP6STAT_INC(ip6s_odropped);
 287                         return (ENOBUFS);
 288                 }
 289
 290                 *mnext = m;
 291                 mnext = &m->m_nextpkt;
 292                 m->m_data += max_linkhdr;
 293                 mhip6 = mtod(m, struct ip6_hdr *);
 294                 *mhip6 = *ip6;
 295                 m->m_len = sizeof(*mhip6);
 296                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 297                 if (error) {
 298                         IP6STAT_INC(ip6s_odropped);
 299                         return (error);
 300                 }
 301                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 302                 if (off + fraglen >= tlen)
 303                         fraglen = tlen - off;
 304                 else
 305                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 306                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 307                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 308                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 309                         IP6STAT_INC(ip6s_odropped);
 310                         return (ENOBUFS);
 311                 }
 312                 m_cat(m, m_frgpart);
 313                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 314                 ip6f->ip6f_reserved = 0;
 315                 ip6f->ip6f_ident = id;
 316                 ip6f->ip6f_nxt = nextproto;
 317                 IP6STAT_INC(ip6s_ofragments);
 318                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 319         }
 320
 321         return (0);
 322 }
 323
 324 static int
 325 ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp,
 326     struct mbuf *m, struct sockaddr_in6 *dst, struct route_in6 *ro,
 327     bool stamp_tag)
 328 {
 329 #ifdef KERN_TLS
 330         struct ktls_session *tls = NULL;
 331 #endif
 332         struct m_snd_tag *mst;
 333         int error;
 334
 335         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 336         mst = NULL;
 337
 338 #ifdef KERN_TLS
 339         /*
 340          * If this is an unencrypted TLS record, save a reference to
 341          * the record.  This local reference is used to call
 342          * ktls_output_eagain after the mbuf has been freed (thus
 343          * dropping the mbuf's reference) in if_output.
 344          */
 345         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 346                 tls = ktls_hold(m->m_next->m_epg_tls);
 347                 mst = tls->snd_tag;
 348
 349                 /*
 350                  * If a TLS session doesn't have a valid tag, it must
 351                  * have had an earlier ifp mismatch, so drop this
 352                  * packet.
 353                  */
 354                 if (mst == NULL) {
 355                         error = EAGAIN;
 356                         goto done;
 357                 }
 358                 /*
 359                  * Always stamp tags that include NIC ktls.
 360                  */
 361                 stamp_tag = true;
 362         }
 363 #endif
 364 #ifdef RATELIMIT
 365         if (inp != NULL && mst == NULL) {
 366                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 367                     (inp->inp_snd_tag != NULL &&
 368                     inp->inp_snd_tag->ifp != ifp))
 369                         in_pcboutput_txrtlmt(inp, ifp, m);
 370
 371                 if (inp->inp_snd_tag != NULL)
 372                         mst = inp->inp_snd_tag;
 373         }
 374 #endif
 375         if (stamp_tag && mst != NULL) {
 376                 KASSERT(m->m_pkthdr.rcvif == NULL,
 377                     ("trying to add a send tag to a forwarded packet"));
 378                 if (mst->ifp != ifp) {
 379                         error = EAGAIN;
 380                         goto done;
 381                 }
 382
 383                 /* stamp send tag on mbuf */
 384                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 385                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 386         }
 387
 388         error = nd6_output_ifp(ifp, origifp, m, dst, (struct route *)ro);
 389
 390 done:
 391         /* Check for route change invalidating send tags. */
 392 #ifdef KERN_TLS
 393         if (tls != NULL) {
 394                 if (error == EAGAIN)
 395                         error = ktls_output_eagain(inp, tls);
 396                 ktls_free(tls);
 397         }
 398 #endif
 399 #ifdef RATELIMIT
 400         if (error == EAGAIN)
 401                 in_pcboutput_eagain(inp);
 402 #endif
 403         return (error);
 404 }
 405
 406 /*
 407  * IP6 output.
 408  * The packet in mbuf chain m contains a skeletal IP6 header (with pri, len,
 409  * nxt, hlim, src, dst).
 410  * This function may modify ver and hlim only.
 411  * The mbuf chain containing the packet will be freed.
 412  * The mbuf opt, if present, will not be freed.
 413  * If route_in6 ro is present and has ro_nh initialized, route lookup would be
 414  * skipped and ro->ro_nh would be used. If ro is present but ro->ro_nh is NULL,
 415  * then result of route lookup is stored in ro->ro_nh.
 416  *
 417  * Type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and nd_ifinfo.linkmtu
 418  * is uint32_t.  So we use u_long to hold largest one, which is rt_mtu.
 419  *
 420  * ifpp - XXX: just for statistics
 421  */
 422 /*
 423  * XXX TODO: no flowid is assigned for outbound flows?
 424  */
 425 int
 426 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 427     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 428     struct ifnet **ifpp, struct inpcb *inp)
 429 {
 430         struct ip6_hdr *ip6;
 431         struct ifnet *ifp, *origifp;
 432         struct mbuf *m = m0;
 433         struct mbuf *mprev;
 434         struct route_in6 *ro_pmtu;
 435         struct nhop_object *nh;
 436         struct sockaddr_in6 *dst, sin6, src_sa, dst_sa;
 437         struct in6_addr odst;
 438         u_char *nexthdrp;
 439         int tlen, len;
 440         int error = 0;
 441         int vlan_pcp = -1;
 442         struct in6_ifaddr *ia = NULL;
 443         u_long mtu;
 444         int alwaysfrag, dontfrag;
 445         u_int32_t optlen, plen = 0, unfragpartlen;
 446         struct ip6_exthdrs exthdrs;
 447         struct in6_addr src0, dst0;
 448         u_int32_t zone;
 449         bool hdrsplit;
 450         int sw_csum, tso;
 451         int needfiblookup;
 452         uint32_t fibnum;
 453         struct m_tag *fwd_tag = NULL;
 454         uint32_t id;
 455
 456         NET_EPOCH_ASSERT();
 457
 458         if (inp != NULL) {
 459                 INP_LOCK_ASSERT(inp);
 460                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 461                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 462                         /* Unconditionally set flowid. */
 463                         m->m_pkthdr.flowid = inp->inp_flowid;
 464                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 465                 }
 466                 if ((inp->inp_flags2 & INP_2PCP_SET) != 0)
 467                         vlan_pcp = (inp->inp_flags2 & INP_2PCP_MASK) >>
 468                             INP_2PCP_SHIFT;
 469 #ifdef NUMA
 470                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 471 #endif
 472         }
 473
 474 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 475         /*
 476          * IPSec checking which handles several cases.
 477          * FAST IPSEC: We re-injected the packet.
 478          * XXX: need scope argument.
 479          */
 480         if (IPSEC_ENABLED(ipv6)) {
 481                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 482                         if (error == EINPROGRESS)
 483                                 error = 0;
 484                         goto done;
 485                 }
 486         }
 487 #endif /* IPSEC */
 488
 489         /* Source address validation. */
 490         ip6 = mtod(m, struct ip6_hdr *);
 491         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 492             (flags & IPV6_UNSPECSRC) == 0) {
 493                 error = EOPNOTSUPP;
 494                 IP6STAT_INC(ip6s_badscope);
 495                 goto bad;
 496         }
 497         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 498                 error = EOPNOTSUPP;
 499                 IP6STAT_INC(ip6s_badscope);
 500                 goto bad;
 501         }
 502
 503         /*
 504          * If we are given packet options to add extension headers prepare them.
 505          * Calculate the total length of the extension header chain.
 506          * Keep the length of the unfragmentable part for fragmentation.
 507          */
 508         bzero(&exthdrs, sizeof(exthdrs));
 509         optlen = 0;
 510         unfragpartlen = sizeof(struct ip6_hdr);
 511         if (opt) {
 512                 /* Hop-by-Hop options header. */
 513                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh, optlen);
 514
 515                 /* Destination options header (1st part). */
 516                 if (opt->ip6po_rthdr) {
 517 #ifndef RTHDR_SUPPORT_IMPLEMENTED
 518                         /*
 519                          * If there is a routing header, discard the packet
 520                          * right away here. RH0/1 are obsolete and we do not
 521                          * currently support RH2/3/4.
 522                          * People trying to use RH253/254 may want to disable
 523                          * this check.
 524                          * The moment we do support any routing header (again)
 525                          * this block should check the routing type more
 526                          * selectively.
 527                          */
 528                         error = EINVAL;
 529                         goto bad;
 530 #endif
 531
 532                         /*
 533                          * Destination options header (1st part).
 534                          * This only makes sense with a routing header.
 535                          * See Section 9.2 of RFC 3542.
 536                          * Disabling this part just for MIP6 convenience is
 537                          * a bad idea.  We need to think carefully about a
 538                          * way to make the advanced API coexist with MIP6
 539                          * options, which might automatically be inserted in
 540                          * the kernel.
 541                          */
 542                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1,
 543                             optlen);
 544                 }
 545                 /* Routing header. */
 546                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr, optlen);
 547
 548                 unfragpartlen += optlen;
 549
 550                 /*
 551                  * NOTE: we don't add AH/ESP length here (done in
 552                  * ip6_ipsec_output()).
 553                  */
 554
 555                 /* Destination options header (2nd part). */
 556                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2, optlen);
 557         }
 558
 559         /*
 560          * If there is at least one extension header,
 561          * separate IP6 header from the payload.
 562          */
 563         hdrsplit = false;
 564         if (optlen) {
 565                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 566                         m = NULL;
 567                         goto freehdrs;
 568                 }
 569                 m = exthdrs.ip6e_ip6;
 570                 ip6 = mtod(m, struct ip6_hdr *);
 571                 hdrsplit = true;
 572         }
 573
 574         /* Adjust mbuf packet header length. */
 575         m->m_pkthdr.len += optlen;
 576         plen = m->m_pkthdr.len - sizeof(*ip6);
 577
 578         /* If this is a jumbo payload, insert a jumbo payload option. */
 579         if (plen > IPV6_MAXPACKET) {
 580                 if (!hdrsplit) {
 581                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 582                                 m = NULL;
 583                                 goto freehdrs;
 584                         }
 585                         m = exthdrs.ip6e_ip6;
 586                         ip6 = mtod(m, struct ip6_hdr *);
 587                         hdrsplit = true;
 588                 }
 589                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 590                         goto freehdrs;
 591                 ip6->ip6_plen = 0;
 592         } else
 593                 ip6->ip6_plen = htons(plen);
 594         nexthdrp = &ip6->ip6_nxt;
 595
 596         if (optlen) {
 597                 /*
 598                  * Concatenate headers and fill in next header fields.
 599                  * Here we have, on "m"
 600                  *      IPv6 payload
 601                  * and we insert headers accordingly.
 602                  * Finally, we should be getting:
 603                  *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload].
 604                  *
 605                  * During the header composing process "m" points to IPv6
 606                  * header.  "mprev" points to an extension header prior to esp.
 607                  */
 608                 mprev = m;
 609
 610                 /*
 611                  * We treat dest2 specially.  This makes IPsec processing
 612                  * much easier.  The goal here is to make mprev point the
 613                  * mbuf prior to dest2.
 614                  *
 615                  * Result: IPv6 dest2 payload.
 616                  * m and mprev will point to IPv6 header.
 617                  */
 618                 if (exthdrs.ip6e_dest2) {
 619                         if (!hdrsplit)
 620                                 panic("%s:%d: assumption failed: "
 621                                     "hdr not split: hdrsplit %d exthdrs %p",
 622                                     __func__, __LINE__, hdrsplit, &exthdrs);
 623                         exthdrs.ip6e_dest2->m_next = m->m_next;
 624                         m->m_next = exthdrs.ip6e_dest2;
 625                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 626                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 627                 }
 628
 629                 /*
 630                  * Result: IPv6 hbh dest1 rthdr dest2 payload.
 631                  * m will point to IPv6 header.  mprev will point to the
 632                  * extension header prior to dest2 (rthdr in the above case).
 633                  */
 634                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 635                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 636                            IPPROTO_DSTOPTS);
 637                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 638                            IPPROTO_ROUTING);
 639         }
 640
 641         IP6STAT_INC(ip6s_localout);
 642
 643         /* Route packet. */
 644         ro_pmtu = ro;
 645         if (opt && opt->ip6po_rthdr)
 646                 ro = &opt->ip6po_route;
 647         if (ro != NULL)
 648                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 649         else
 650                 dst = &sin6;
 651         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 652
 653 again:
 654         /*
 655          * If specified, try to fill in the traffic class field.
 656          * Do not override if a non-zero value is already set.
 657          * We check the diffserv field and the ECN field separately.
 658          */
 659         if (opt && opt->ip6po_tclass >= 0) {
 660                 int mask = 0;
 661
 662                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 663                         mask |= 0xfc;
 664                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 665                         mask |= 0x03;
 666                 if (mask != 0)
 667                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 668         }
 669
 670         /* Fill in or override the hop limit field, if necessary. */
 671         if (opt && opt->ip6po_hlim != -1)
 672                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 673         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 674                 if (im6o != NULL)
 675                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 676                 else
 677                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 678         }
 679
 680         if (ro == NULL || ro->ro_nh == NULL) {
 681                 bzero(dst, sizeof(*dst));
 682                 dst->sin6_family = AF_INET6;
 683                 dst->sin6_len = sizeof(*dst);
 684                 dst->sin6_addr = ip6->ip6_dst;
 685         }
 686         /*
 687          * Validate route against routing table changes.
 688          * Make sure that the address family is set in route.
 689          */
 690         nh = NULL;
 691         ifp = NULL;
 692         mtu = 0;
 693         if (ro != NULL) {
 694                 if (ro->ro_nh != NULL && inp != NULL) {
 695                         ro->ro_dst.sin6_family = AF_INET6; /* XXX KASSERT? */
 696                         NH_VALIDATE((struct route *)ro, &inp->inp_rt_cookie,
 697                             fibnum);
 698                 }
 699                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 700                     (!NH_IS_VALID(ro->ro_nh) ||
 701                     ro->ro_dst.sin6_family != AF_INET6 ||
 702                     !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)))
 703                         RO_INVALIDATE_CACHE(ro);
 704
 705                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 706                     ro->ro_dst.sin6_family == AF_INET6 &&
 707                     IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 708                         nh = ro->ro_nh;
 709                         ifp = nh->nh_ifp;
 710                 } else {
 711                         if (ro->ro_lle)
 712                                 LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 713                         ro->ro_lle = NULL;
 714                         if (fwd_tag == NULL) {
 715                                 bzero(&dst_sa, sizeof(dst_sa));
 716                                 dst_sa.sin6_family = AF_INET6;
 717                                 dst_sa.sin6_len = sizeof(dst_sa);
 718                                 dst_sa.sin6_addr = ip6->ip6_dst;
 719                         }
 720                         error = in6_selectroute(&dst_sa, opt, im6o, ro, &ifp,
 721                             &nh, fibnum, m->m_pkthdr.flowid);
 722                         if (error != 0) {
 723                                 IP6STAT_INC(ip6s_noroute);
 724                                 if (ifp != NULL)
 725                                         in6_ifstat_inc(ifp, ifs6_out_discard);
 726                                 goto bad;
 727                         }
 728                         if (ifp != NULL)
 729                             mtu = ifp->if_mtu;
 730                 }
 731                 if (nh == NULL) {
 732                         /*
 733                          * If in6_selectroute() does not return a nexthop
 734                          * dst may not have been updated.
 735                          */
 736                         *dst = dst_sa;  /* XXX */
 737                 } else {
 738                         if (nh->nh_flags & NHF_HOST)
 739                             mtu = nh->nh_mtu;
 740                         ia = (struct in6_ifaddr *)(nh->nh_ifa);
 741                         counter_u64_add(nh->nh_pksent, 1);
 742                 }
 743         } else {
 744                 struct nhop_object *nh;
 745                 struct in6_addr kdst;
 746                 uint32_t scopeid;
 747
 748                 if (fwd_tag == NULL) {
 749                         bzero(&dst_sa, sizeof(dst_sa));
 750                         dst_sa.sin6_family = AF_INET6;
 751                         dst_sa.sin6_len = sizeof(dst_sa);
 752                         dst_sa.sin6_addr = ip6->ip6_dst;
 753                 }
 754
 755                 if (IN6_IS_ADDR_MULTICAST(&dst_sa.sin6_addr) &&
 756                     im6o != NULL &&
 757                     (ifp = im6o->im6o_multicast_ifp) != NULL) {
 758                         /* We do not need a route lookup. */
 759                         *dst = dst_sa;  /* XXX */
 760                         goto nonh6lookup;
 761                 }
 762
 763                 in6_splitscope(&dst_sa.sin6_addr, &kdst, &scopeid);
 764
 765                 if (IN6_IS_ADDR_MC_LINKLOCAL(&dst_sa.sin6_addr) ||
 766                     IN6_IS_ADDR_MC_NODELOCAL(&dst_sa.sin6_addr)) {
 767                         if (scopeid > 0) {
 768                                 ifp = in6_getlinkifnet(scopeid);
 769                                 if (ifp == NULL) {
 770                                         error = EHOSTUNREACH;
 771                                         goto bad;
 772                                 }
 773                                 *dst = dst_sa;  /* XXX */
 774                                 goto nonh6lookup;
 775                         }
 776                 }
 777
 778                 nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
 779                 if (nh == NULL) {
 780                         IP6STAT_INC(ip6s_noroute);
 781                         /* No ifp in6_ifstat_inc(ifp, ifs6_out_discard); */
 782                         error = EHOSTUNREACH;;
 783                         goto bad;
 784                 }
 785
 786                 ifp = nh->nh_ifp;
 787                 mtu = nh->nh_mtu;
 788                 ia = ifatoia6(nh->nh_ifa);
 789                 if (nh->nh_flags & NHF_GATEWAY)
 790                         dst->sin6_addr = nh->gw6_sa.sin6_addr;
 791 nonh6lookup:
 792                 ;
 793         }
 794
 795         /* Then nh (for unicast) and ifp must be non-NULL valid values. */
 796         if ((flags & IPV6_FORWARDING) == 0) {
 797                 /* XXX: the FORWARDING flag can be set for mrouting. */
 798                 in6_ifstat_inc(ifp, ifs6_out_request);
 799         }
 800
 801         /* Setup data structures for scope ID checks. */
 802         src0 = ip6->ip6_src;
 803         bzero(&src_sa, sizeof(src_sa));
 804         src_sa.sin6_family = AF_INET6;
 805         src_sa.sin6_len = sizeof(src_sa);
 806         src_sa.sin6_addr = ip6->ip6_src;
 807
 808         dst0 = ip6->ip6_dst;
 809         /* Re-initialize to be sure. */
 810         bzero(&dst_sa, sizeof(dst_sa));
 811         dst_sa.sin6_family = AF_INET6;
 812         dst_sa.sin6_len = sizeof(dst_sa);
 813         dst_sa.sin6_addr = ip6->ip6_dst;
 814
 815         /* Check for valid scope ID. */
 816         if (in6_setscope(&src0, ifp, &zone) == 0 &&
 817             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 818             in6_setscope(&dst0, ifp, &zone) == 0 &&
 819             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 820                 /*
 821                  * The outgoing interface is in the zone of the source
 822                  * and destination addresses.
 823                  *
 824                  * Because the loopback interface cannot receive
 825                  * packets with a different scope ID than its own,
 826                  * there is a trick to pretend the outgoing packet
 827                  * was received by the real network interface, by
 828                  * setting "origifp" different from "ifp". This is
 829                  * only allowed when "ifp" is a loopback network
 830                  * interface. Refer to code in nd6_output_ifp() for
 831                  * more details.
 832                  */
 833                 origifp = ifp;
 834
 835                 /*
 836                  * We should use ia_ifp to support the case of sending
 837                  * packets to an address of our own.
 838                  */
 839                 if (ia != NULL && ia->ia_ifp)
 840                         ifp = ia->ia_ifp;
 841
 842         } else if ((ifp->if_flags & IFF_LOOPBACK) == 0 ||
 843             sa6_recoverscope(&src_sa) != 0 ||
 844             sa6_recoverscope(&dst_sa) != 0 ||
 845             dst_sa.sin6_scope_id == 0 ||
 846             (src_sa.sin6_scope_id != 0 &&
 847             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 848             (origifp = ifnet_byindex(dst_sa.sin6_scope_id)) == NULL) {
 849                 /*
 850                  * If the destination network interface is not a
 851                  * loopback interface, or the destination network
 852                  * address has no scope ID, or the source address has
 853                  * a scope ID set which is different from the
 854                  * destination address one, or there is no network
 855                  * interface representing this scope ID, the address
 856                  * pair is considered invalid.
 857                  */
 858                 IP6STAT_INC(ip6s_badscope);
 859                 in6_ifstat_inc(ifp, ifs6_out_discard);
 860                 if (error == 0)
 861                         error = EHOSTUNREACH; /* XXX */
 862                 goto bad;
 863         }
 864         /* All scope ID checks are successful. */
 865
 866         if (nh && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 867                 if (opt && opt->ip6po_nextroute.ro_nh) {
 868                         /*
 869                          * The nexthop is explicitly specified by the
 870                          * application.  We assume the next hop is an IPv6
 871                          * address.
 872                          */
 873                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 874                 }
 875                 else if ((nh->nh_flags & NHF_GATEWAY))
 876                         dst = &nh->gw6_sa;
 877         }
 878
 879         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 880                 m->m_flags &= ~(M_BCAST | M_MCAST); /* Just in case. */
 881         } else {
 882                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 883                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 884
 885                 /* Confirm that the outgoing interface supports multicast. */
 886                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 887                         IP6STAT_INC(ip6s_noroute);
 888                         in6_ifstat_inc(ifp, ifs6_out_discard);
 889                         error = ENETUNREACH;
 890                         goto bad;
 891                 }
 892                 if ((im6o == NULL && in6_mcast_loop) ||
 893                     (im6o && im6o->im6o_multicast_loop)) {
 894                         /*
 895                          * Loop back multicast datagram if not expressly
 896                          * forbidden to do so, even if we have not joined
 897                          * the address; protocols will filter it later,
 898                          * thus deferring a hash lookup and lock acquisition
 899                          * at the expense of an m_copym().
 900                          */
 901                         ip6_mloopback(ifp, m);
 902                 } else {
 903                         /*
 904                          * If we are acting as a multicast router, perform
 905                          * multicast forwarding as if the packet had just
 906                          * arrived on the interface to which we are about
 907                          * to send.  The multicast forwarding function
 908                          * recursively calls this function, using the
 909                          * IPV6_FORWARDING flag to prevent infinite recursion.
 910                          *
 911                          * Multicasts that are looped back by ip6_mloopback(),
 912                          * above, will be forwarded by the ip6_input() routine,
 913                          * if necessary.
 914                          */
 915                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 916                                 /*
 917                                  * XXX: ip6_mforward expects that rcvif is NULL
 918                                  * when it is called from the originating path.
 919                                  * However, it may not always be the case.
 920                                  */
 921                                 m->m_pkthdr.rcvif = NULL;
 922                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 923                                         m_freem(m);
 924                                         goto done;
 925                                 }
 926                         }
 927                 }
 928                 /*
 929                  * Multicasts with a hoplimit of zero may be looped back,
 930                  * above, but must not be transmitted on a network.
 931                  * Also, multicasts addressed to the loopback interface
 932                  * are not sent -- the above call to ip6_mloopback() will
 933                  * loop back a copy if this host actually belongs to the
 934                  * destination group on the loopback interface.
 935                  */
 936                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 937                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 938                         m_freem(m);
 939                         goto done;
 940                 }
 941         }
 942
 943         /*
 944          * Fill the outgoing inteface to tell the upper layer
 945          * to increment per-interface statistics.
 946          */
 947         if (ifpp)
 948                 *ifpp = ifp;
 949
 950         /* Determine path MTU. */
 951         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 952                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 953                 goto bad;
 954         KASSERT(mtu > 0, ("%s:%d: mtu %ld, ro_pmtu %p ro %p ifp %p "
 955             "alwaysfrag %d fibnum %u\n", __func__, __LINE__, mtu, ro_pmtu, ro,
 956             ifp, alwaysfrag, fibnum));
 957
 958         /*
 959          * The caller of this function may specify to use the minimum MTU
 960          * in some cases.
 961          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 962          * setting.  The logic is a bit complicated; by default, unicast
 963          * packets will follow path MTU while multicast packets will be sent at
 964          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 965          * including unicast ones will be sent at the minimum MTU.  Multicast
 966          * packets will always be sent at the minimum MTU unless
 967          * IP6PO_MINMTU_DISABLE is explicitly specified.
 968          * See RFC 3542 for more details.
 969          */
 970         if (mtu > IPV6_MMTU) {
 971                 if ((flags & IPV6_MINMTU))
 972                         mtu = IPV6_MMTU;
 973                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 974                         mtu = IPV6_MMTU;
 975                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 976                          (opt == NULL ||
 977                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 978                         mtu = IPV6_MMTU;
 979                 }
 980         }
 981
 982         /*
 983          * Clear embedded scope identifiers if necessary.
 984          * in6_clearscope() will touch the addresses only when necessary.
 985          */
 986         in6_clearscope(&ip6->ip6_src);
 987         in6_clearscope(&ip6->ip6_dst);
 988
 989         /*
 990          * If the outgoing packet contains a hop-by-hop options header,
 991          * it must be examined and processed even by the source node.
 992          * (RFC 2460, section 4.)
 993          */
 994         if (exthdrs.ip6e_hbh) {
 995                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 996                 u_int32_t dummy; /* XXX unused */
 997                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 998
 999 #ifdef DIAGNOSTIC
1000                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
1001                         panic("ip6e_hbh is not contiguous");
1002 #endif
1003                 /*
1004                  *  XXX: if we have to send an ICMPv6 error to the sender,
1005                  *       we need the M_LOOP flag since icmp6_error() expects
1006                  *       the IPv6 and the hop-by-hop options header are
1007                  *       contiguous unless the flag is set.
1008                  */
1009                 m->m_flags |= M_LOOP;
1010                 m->m_pkthdr.rcvif = ifp;
1011                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
1012                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
1013                     &dummy, &plen) < 0) {
1014                         /* m was already freed at this point. */
1015                         error = EINVAL;/* better error? */
1016                         goto done;
1017                 }
1018                 m->m_flags &= ~M_LOOP; /* XXX */
1019                 m->m_pkthdr.rcvif = NULL;
1020         }
1021
1022         /* Jump over all PFIL processing if hooks are not active. */
1023         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
1024                 goto passout;
1025
1026         odst = ip6->ip6_dst;
1027         /* Run through list of hooks for output packets. */
1028         switch (pfil_run_hooks(V_inet6_pfil_head, &m, ifp, PFIL_OUT, inp)) {
1029         case PFIL_PASS:
1030                 ip6 = mtod(m, struct ip6_hdr *);
1031                 break;
1032         case PFIL_DROPPED:
1033                 error = EACCES;
1034                 /* FALLTHROUGH */
1035         case PFIL_CONSUMED:
1036                 goto done;
1037         }
1038
1039         needfiblookup = 0;
1040         /* See if destination IP address was changed by packet filter. */
1041         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
1042                 m->m_flags |= M_SKIP_FIREWALL;
1043                 /* If destination is now ourself drop to ip6_input(). */
1044                 if (in6_localip(&ip6->ip6_dst)) {
1045                         m->m_flags |= M_FASTFWD_OURS;
1046                         if (m->m_pkthdr.rcvif == NULL)
1047                                 m->m_pkthdr.rcvif = V_loif;
1048                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1049                                 m->m_pkthdr.csum_flags |=
1050                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1051                                 m->m_pkthdr.csum_data = 0xffff;
1052                         }
1053 #if defined(SCTP) || defined(SCTP_SUPPORT)
1054                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1055                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1056 #endif
1057                         error = netisr_queue(NETISR_IPV6, m);
1058                         goto done;
1059                 } else {
1060                         if (ro != NULL)
1061                                 RO_INVALIDATE_CACHE(ro);
1062                         needfiblookup = 1; /* Redo the routing table lookup. */
1063                 }
1064         }
1065         /* See if fib was changed by packet filter. */
1066         if (fibnum != M_GETFIB(m)) {
1067                 m->m_flags |= M_SKIP_FIREWALL;
1068                 fibnum = M_GETFIB(m);
1069                 if (ro != NULL)
1070                         RO_INVALIDATE_CACHE(ro);
1071                 needfiblookup = 1;
1072         }
1073         if (needfiblookup)
1074                 goto again;
1075
1076         /* See if local, if yes, send it to netisr. */
1077         if (m->m_flags & M_FASTFWD_OURS) {
1078                 if (m->m_pkthdr.rcvif == NULL)
1079                         m->m_pkthdr.rcvif = V_loif;
1080                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1081                         m->m_pkthdr.csum_flags |=
1082                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1083                         m->m_pkthdr.csum_data = 0xffff;
1084                 }
1085 #if defined(SCTP) || defined(SCTP_SUPPORT)
1086                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1087                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1088 #endif
1089                 error = netisr_queue(NETISR_IPV6, m);
1090                 goto done;
1091         }
1092         /* Or forward to some other address? */
1093         if ((m->m_flags & M_IP6_NEXTHOP) &&
1094             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
1095                 if (ro != NULL)
1096                         dst = (struct sockaddr_in6 *)&ro->ro_dst;
1097                 else
1098                         dst = &sin6;
1099                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
1100                 m->m_flags |= M_SKIP_FIREWALL;
1101                 m->m_flags &= ~M_IP6_NEXTHOP;
1102                 m_tag_delete(m, fwd_tag);
1103                 goto again;
1104         }
1105
1106 passout:
1107         if (vlan_pcp > -1)
1108                 EVL_APPLY_PRI(m, vlan_pcp);
1109         /*
1110          * Send the packet to the outgoing interface.
1111          * If necessary, do IPv6 fragmentation before sending.
1112          *
1113          * The logic here is rather complex:
1114          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
1115          * 1-a: send as is if tlen <= path mtu
1116          * 1-b: fragment if tlen > path mtu
1117          *
1118          * 2: if user asks us not to fragment (dontfrag == 1)
1119          * 2-a: send as is if tlen <= interface mtu
1120          * 2-b: error if tlen > interface mtu
1121          *
1122          * 3: if we always need to attach fragment header (alwaysfrag == 1)
1123          *      always fragment
1124          *
1125          * 4: if dontfrag == 1 && alwaysfrag == 1
1126          *      error, as we cannot handle this conflicting request.
1127          */
1128         sw_csum = m->m_pkthdr.csum_flags;
1129         if (!hdrsplit) {
1130                 tso = ((sw_csum & ifp->if_hwassist &
1131                     (CSUM_TSO | CSUM_INNER_TSO)) != 0) ? 1 : 0;
1132                 sw_csum &= ~ifp->if_hwassist;
1133         } else
1134                 tso = 0;
1135         /*
1136          * If we added extension headers, we will not do TSO and calculate the
1137          * checksums ourselves for now.
1138          * XXX-BZ  Need a framework to know when the NIC can handle it, even
1139          * with ext. hdrs.
1140          */
1141         error = ip6_output_delayed_csum(m, ifp, sw_csum, plen, optlen, false);
1142         if (error != 0)
1143                 goto bad;
1144         /* XXX-BZ m->m_pkthdr.csum_flags &= ~ifp->if_hwassist; */
1145         tlen = m->m_pkthdr.len;
1146
1147         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1148                 dontfrag = 1;
1149         else
1150                 dontfrag = 0;
1151         if (dontfrag && alwaysfrag) {   /* Case 4. */
1152                 /* Conflicting request - can't transmit. */
1153                 error = EMSGSIZE;
1154                 goto bad;
1155         }
1156         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* Case 2-b. */
1157                 /*
1158                  * Even if the DONTFRAG option is specified, we cannot send the
1159                  * packet when the data length is larger than the MTU of the
1160                  * outgoing interface.
1161                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1162                  * application wanted to know the MTU value. Also return an
1163                  * error code (this is not described in the API spec).
1164                  */
1165                 if (inp != NULL)
1166                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1167                 error = EMSGSIZE;
1168                 goto bad;
1169         }
1170
1171         /* Transmit packet without fragmentation. */
1172         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* Cases 1-a and 2-a. */
1173                 struct in6_ifaddr *ia6;
1174
1175                 ip6 = mtod(m, struct ip6_hdr *);
1176                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1177                 if (ia6) {
1178                         /* Record statistics for this interface address. */
1179                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1180                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1181                             m->m_pkthdr.len);
1182                         ifa_free(&ia6->ia_ifa);
1183                 }
1184                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1185                     (flags & IP_NO_SND_TAG_RL) ? false : true);
1186                 goto done;
1187         }
1188
1189         /* Try to fragment the packet.  Cases 1-b and 3. */
1190         if (mtu < IPV6_MMTU) {
1191                 /* Path MTU cannot be less than IPV6_MMTU. */
1192                 error = EMSGSIZE;
1193                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1194                 goto bad;
1195         } else if (ip6->ip6_plen == 0) {
1196                 /* Jumbo payload cannot be fragmented. */
1197                 error = EMSGSIZE;
1198                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1199                 goto bad;
1200         } else {
1201                 u_char nextproto;
1202
1203                 /*
1204                  * Too large for the destination or interface;
1205                  * fragment if possible.
1206                  * Must be able to put at least 8 bytes per fragment.
1207                  */
1208                 if (mtu > IPV6_MAXPACKET)
1209                         mtu = IPV6_MAXPACKET;
1210
1211                 len = (mtu - unfragpartlen - sizeof(struct ip6_frag)) & ~7;
1212                 if (len < 8) {
1213                         error = EMSGSIZE;
1214                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1215                         goto bad;
1216                 }
1217
1218                 /*
1219                  * If the interface will not calculate checksums on
1220                  * fragmented packets, then do it here.
1221                  * XXX-BZ handle the hw offloading case.  Need flags.
1222                  */
1223                 error = ip6_output_delayed_csum(m, ifp, m->m_pkthdr.csum_flags,
1224                     plen, optlen, true);
1225                 if (error != 0)
1226                         goto bad;
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_REUSEADDR:
1645                                 INP_WLOCK(inp);
1646                                 if ((so->so_options & SO_REUSEADDR) != 0)
1647                                         inp->inp_flags2 |= INP_REUSEADDR;
1648                                 else
1649                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1650                                 INP_WUNLOCK(inp);
1651                                 error = 0;
1652                                 break;
1653                         case SO_REUSEPORT:
1654                                 INP_WLOCK(inp);
1655                                 if ((so->so_options & SO_REUSEPORT) != 0)
1656                                         inp->inp_flags2 |= INP_REUSEPORT;
1657                                 else
1658                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1659                                 INP_WUNLOCK(inp);
1660                                 error = 0;
1661                                 break;
1662                         case SO_REUSEPORT_LB:
1663                                 INP_WLOCK(inp);
1664                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1665                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1666                                 else
1667                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1668                                 INP_WUNLOCK(inp);
1669                                 error = 0;
1670                                 break;
1671                         case SO_SETFIB:
1672                                 INP_WLOCK(inp);
1673                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1674                                 INP_WUNLOCK(inp);
1675                                 error = 0;
1676                                 break;
1677                         case SO_MAX_PACING_RATE:
1678 #ifdef RATELIMIT
1679                                 INP_WLOCK(inp);
1680                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1681                                 INP_WUNLOCK(inp);
1682                                 error = 0;
1683 #else
1684                                 error = EOPNOTSUPP;
1685 #endif
1686                                 break;
1687                         default:
1688                                 break;
1689                         }
1690                 }
1691         } else {                /* level == IPPROTO_IPV6 */
1692                 switch (op) {
1693                 case SOPT_SET:
1694                         switch (optname) {
1695                         case IPV6_2292PKTOPTIONS:
1696 #ifdef IPV6_PKTOPTIONS
1697                         case IPV6_PKTOPTIONS:
1698 #endif
1699                         {
1700                                 struct mbuf *m;
1701
1702                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1703                                         printf("ip6_ctloutput: mbuf limit hit\n");
1704                                         error = ENOBUFS;
1705                                         break;
1706                                 }
1707
1708                                 error = soopt_getm(sopt, &m); /* XXX */
1709                                 if (error != 0)
1710                                         break;
1711                                 error = soopt_mcopyin(sopt, m); /* XXX */
1712                                 if (error != 0)
1713                                         break;
1714                                 INP_WLOCK(inp);
1715                                 error = ip6_pcbopts(&inp->in6p_outputopts, m,
1716                                     so, sopt);
1717                                 INP_WUNLOCK(inp);
1718                                 m_freem(m); /* XXX */
1719                                 break;
1720                         }
1721
1722                         /*
1723                          * Use of some Hop-by-Hop options or some
1724                          * Destination options, might require special
1725                          * privilege.  That is, normal applications
1726                          * (without special privilege) might be forbidden
1727                          * from setting certain options in outgoing packets,
1728                          * and might never see certain options in received
1729                          * packets. [RFC 2292 Section 6]
1730                          * KAME specific note:
1731                          *  KAME prevents non-privileged users from sending or
1732                          *  receiving ANY hbh/dst options in order to avoid
1733                          *  overhead of parsing options in the kernel.
1734                          */
1735                         case IPV6_RECVHOPOPTS:
1736                         case IPV6_RECVDSTOPTS:
1737                         case IPV6_RECVRTHDRDSTOPTS:
1738                                 if (td != NULL) {
1739                                         error = priv_check(td,
1740                                             PRIV_NETINET_SETHDROPTS);
1741                                         if (error)
1742                                                 break;
1743                                 }
1744                                 /* FALLTHROUGH */
1745                         case IPV6_UNICAST_HOPS:
1746                         case IPV6_HOPLIMIT:
1747
1748                         case IPV6_RECVPKTINFO:
1749                         case IPV6_RECVHOPLIMIT:
1750                         case IPV6_RECVRTHDR:
1751                         case IPV6_RECVPATHMTU:
1752                         case IPV6_RECVTCLASS:
1753                         case IPV6_RECVFLOWID:
1754 #ifdef  RSS
1755                         case IPV6_RECVRSSBUCKETID:
1756 #endif
1757                         case IPV6_V6ONLY:
1758                         case IPV6_AUTOFLOWLABEL:
1759                         case IPV6_ORIGDSTADDR:
1760                         case IPV6_BINDANY:
1761                         case IPV6_BINDMULTI:
1762 #ifdef  RSS
1763                         case IPV6_RSS_LISTEN_BUCKET:
1764 #endif
1765                         case IPV6_VLAN_PCP:
1766                                 if (optname == IPV6_BINDANY && td != NULL) {
1767                                         error = priv_check(td,
1768                                             PRIV_NETINET_BINDANY);
1769                                         if (error)
1770                                                 break;
1771                                 }
1772
1773                                 if (optlen != sizeof(int)) {
1774                                         error = EINVAL;
1775                                         break;
1776                                 }
1777                                 error = sooptcopyin(sopt, &optval,
1778                                         sizeof optval, sizeof optval);
1779                                 if (error)
1780                                         break;
1781                                 switch (optname) {
1782                                 case IPV6_UNICAST_HOPS:
1783                                         if (optval < -1 || optval >= 256)
1784                                                 error = EINVAL;
1785                                         else {
1786                                                 /* -1 = kernel default */
1787                                                 inp->in6p_hops = optval;
1788                                                 if ((inp->inp_vflag &
1789                                                      INP_IPV4) != 0)
1790                                                         inp->inp_ip_ttl = optval;
1791                                         }
1792                                         break;
1793 #define OPTSET(bit) \
1794 do { \
1795         INP_WLOCK(inp); \
1796         if (optval) \
1797                 inp->inp_flags |= (bit); \
1798         else \
1799                 inp->inp_flags &= ~(bit); \
1800         INP_WUNLOCK(inp); \
1801 } while (/*CONSTCOND*/ 0)
1802 #define OPTSET2292(bit) \
1803 do { \
1804         INP_WLOCK(inp); \
1805         inp->inp_flags |= IN6P_RFC2292; \
1806         if (optval) \
1807                 inp->inp_flags |= (bit); \
1808         else \
1809                 inp->inp_flags &= ~(bit); \
1810         INP_WUNLOCK(inp); \
1811 } while (/*CONSTCOND*/ 0)
1812 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1813
1814 #define OPTSET2_N(bit, val) do {                                        \
1815         if (val)                                                        \
1816                 inp->inp_flags2 |= bit;                                 \
1817         else                                                            \
1818                 inp->inp_flags2 &= ~bit;                                \
1819 } while (0)
1820 #define OPTSET2(bit, val) do {                                          \
1821         INP_WLOCK(inp);                                                 \
1822         OPTSET2_N(bit, val);                                            \
1823         INP_WUNLOCK(inp);                                               \
1824 } while (0)
1825 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1826 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1827 do {                                                                    \
1828         INP_WLOCK(inp);                                                 \
1829         if (OPTBIT(IN6P_RFC2292)) {                                     \
1830                 error = EINVAL;                                         \
1831         } else {                                                        \
1832                 if (optval)                                             \
1833                         inp->inp_flags |= (bit);                        \
1834                 else                                                    \
1835                         inp->inp_flags &= ~(bit);                       \
1836         }                                                               \
1837         INP_WUNLOCK(inp);                                               \
1838 } while (/*CONSTCOND*/ 0)
1839
1840                                 case IPV6_RECVPKTINFO:
1841                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1842                                         break;
1843
1844                                 case IPV6_HOPLIMIT:
1845                                 {
1846                                         struct ip6_pktopts **optp;
1847
1848                                         /* cannot mix with RFC2292 */
1849                                         if (OPTBIT(IN6P_RFC2292)) {
1850                                                 error = EINVAL;
1851                                                 break;
1852                                         }
1853                                         INP_WLOCK(inp);
1854                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1855                                                 INP_WUNLOCK(inp);
1856                                                 return (ECONNRESET);
1857                                         }
1858                                         optp = &inp->in6p_outputopts;
1859                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1860                                             (u_char *)&optval, sizeof(optval),
1861                                             optp, (td != NULL) ? td->td_ucred :
1862                                             NULL, uproto);
1863                                         INP_WUNLOCK(inp);
1864                                         break;
1865                                 }
1866
1867                                 case IPV6_RECVHOPLIMIT:
1868                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1869                                         break;
1870
1871                                 case IPV6_RECVHOPOPTS:
1872                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1873                                         break;
1874
1875                                 case IPV6_RECVDSTOPTS:
1876                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1877                                         break;
1878
1879                                 case IPV6_RECVRTHDRDSTOPTS:
1880                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1881                                         break;
1882
1883                                 case IPV6_RECVRTHDR:
1884                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1885                                         break;
1886
1887                                 case IPV6_RECVPATHMTU:
1888                                         /*
1889                                          * We ignore this option for TCP
1890                                          * sockets.
1891                                          * (RFC3542 leaves this case
1892                                          * unspecified.)
1893                                          */
1894                                         if (uproto != IPPROTO_TCP)
1895                                                 OPTSET(IN6P_MTU);
1896                                         break;
1897
1898                                 case IPV6_RECVFLOWID:
1899                                         OPTSET2(INP_RECVFLOWID, optval);
1900                                         break;
1901
1902 #ifdef  RSS
1903                                 case IPV6_RECVRSSBUCKETID:
1904                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1905                                         break;
1906 #endif
1907
1908                                 case IPV6_V6ONLY:
1909                                         INP_WLOCK(inp);
1910                                         if (inp->inp_lport ||
1911                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1912                                                 /*
1913                                                  * The socket is already bound.
1914                                                  */
1915                                                 INP_WUNLOCK(inp);
1916                                                 error = EINVAL;
1917                                                 break;
1918                                         }
1919                                         if (optval) {
1920                                                 inp->inp_flags |= IN6P_IPV6_V6ONLY;
1921                                                 inp->inp_vflag &= ~INP_IPV4;
1922                                         } else {
1923                                                 inp->inp_flags &= ~IN6P_IPV6_V6ONLY;
1924                                                 inp->inp_vflag |= INP_IPV4;
1925                                         }
1926                                         INP_WUNLOCK(inp);
1927                                         break;
1928                                 case IPV6_RECVTCLASS:
1929                                         /* cannot mix with RFC2292 XXX */
1930                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1931                                         break;
1932                                 case IPV6_AUTOFLOWLABEL:
1933                                         OPTSET(IN6P_AUTOFLOWLABEL);
1934                                         break;
1935
1936                                 case IPV6_ORIGDSTADDR:
1937                                         OPTSET2(INP_ORIGDSTADDR, optval);
1938                                         break;
1939                                 case IPV6_BINDANY:
1940                                         OPTSET(INP_BINDANY);
1941                                         break;
1942
1943                                 case IPV6_BINDMULTI:
1944                                         OPTSET2(INP_BINDMULTI, optval);
1945                                         break;
1946 #ifdef  RSS
1947                                 case IPV6_RSS_LISTEN_BUCKET:
1948                                         if ((optval >= 0) &&
1949                                             (optval < rss_getnumbuckets())) {
1950                                                 INP_WLOCK(inp);
1951                                                 inp->inp_rss_listen_bucket = optval;
1952                                                 OPTSET2_N(INP_RSS_BUCKET_SET, 1);
1953                                                 INP_WUNLOCK(inp);
1954                                         } else {
1955                                                 error = EINVAL;
1956                                         }
1957                                         break;
1958 #endif
1959                                 case IPV6_VLAN_PCP:
1960                                         if ((optval >= -1) && (optval <=
1961                                             (INP_2PCP_MASK >> INP_2PCP_SHIFT))) {
1962                                                 if (optval == -1) {
1963                                                         INP_WLOCK(inp);
1964                                                         inp->inp_flags2 &=
1965                                                             ~(INP_2PCP_SET |
1966                                                             INP_2PCP_MASK);
1967                                                         INP_WUNLOCK(inp);
1968                                                 } else {
1969                                                         INP_WLOCK(inp);
1970                                                         inp->inp_flags2 |=
1971                                                             INP_2PCP_SET;
1972                                                         inp->inp_flags2 &=
1973                                                             ~INP_2PCP_MASK;
1974                                                         inp->inp_flags2 |=
1975                                                             optval <<
1976                                                             INP_2PCP_SHIFT;
1977                                                         INP_WUNLOCK(inp);
1978                                                 }
1979                                         } else
1980                                                 error = EINVAL;
1981                                         break;
1982                                 }
1983                                 break;
1984
1985                         case IPV6_TCLASS:
1986                         case IPV6_DONTFRAG:
1987                         case IPV6_USE_MIN_MTU:
1988                         case IPV6_PREFER_TEMPADDR:
1989                                 if (optlen != sizeof(optval)) {
1990                                         error = EINVAL;
1991                                         break;
1992                                 }
1993                                 error = sooptcopyin(sopt, &optval,
1994                                         sizeof optval, sizeof optval);
1995                                 if (error)
1996                                         break;
1997                                 {
1998                                         struct ip6_pktopts **optp;
1999                                         INP_WLOCK(inp);
2000                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
2001                                                 INP_WUNLOCK(inp);
2002                                                 return (ECONNRESET);
2003                                         }
2004                                         optp = &inp->in6p_outputopts;
2005                                         error = ip6_pcbopt(optname,
2006                                             (u_char *)&optval, sizeof(optval),
2007                                             optp, (td != NULL) ? td->td_ucred :
2008                                             NULL, uproto);
2009                                         INP_WUNLOCK(inp);
2010                                         break;
2011                                 }
2012
2013                         case IPV6_2292PKTINFO:
2014                         case IPV6_2292HOPLIMIT:
2015                         case IPV6_2292HOPOPTS:
2016                         case IPV6_2292DSTOPTS:
2017                         case IPV6_2292RTHDR:
2018                                 /* RFC 2292 */
2019                                 if (optlen != sizeof(int)) {
2020                                         error = EINVAL;
2021                                         break;
2022                                 }
2023                                 error = sooptcopyin(sopt, &optval,
2024                                         sizeof optval, sizeof optval);
2025                                 if (error)
2026                                         break;
2027                                 switch (optname) {
2028                                 case IPV6_2292PKTINFO:
2029                                         OPTSET2292(IN6P_PKTINFO);
2030                                         break;
2031                                 case IPV6_2292HOPLIMIT:
2032                                         OPTSET2292(IN6P_HOPLIMIT);
2033                                         break;
2034                                 case IPV6_2292HOPOPTS:
2035                                         /*
2036                                          * Check super-user privilege.
2037                                          * See comments for IPV6_RECVHOPOPTS.
2038                                          */
2039                                         if (td != NULL) {
2040                                                 error = priv_check(td,
2041                                                     PRIV_NETINET_SETHDROPTS);
2042                                                 if (error)
2043                                                         return (error);
2044                                         }
2045                                         OPTSET2292(IN6P_HOPOPTS);
2046                                         break;
2047                                 case IPV6_2292DSTOPTS:
2048                                         if (td != NULL) {
2049                                                 error = priv_check(td,
2050                                                     PRIV_NETINET_SETHDROPTS);
2051                                                 if (error)
2052                                                         return (error);
2053                                         }
2054                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
2055                                         break;
2056                                 case IPV6_2292RTHDR:
2057                                         OPTSET2292(IN6P_RTHDR);
2058                                         break;
2059                                 }
2060                                 break;
2061                         case IPV6_PKTINFO:
2062                         case IPV6_HOPOPTS:
2063                         case IPV6_RTHDR:
2064                         case IPV6_DSTOPTS:
2065                         case IPV6_RTHDRDSTOPTS:
2066                         case IPV6_NEXTHOP:
2067                         {
2068                                 /* new advanced API (RFC3542) */
2069                                 u_char *optbuf;
2070                                 u_char optbuf_storage[MCLBYTES];
2071                                 int optlen;
2072                                 struct ip6_pktopts **optp;
2073
2074                                 /* cannot mix with RFC2292 */
2075                                 if (OPTBIT(IN6P_RFC2292)) {
2076                                         error = EINVAL;
2077                                         break;
2078                                 }
2079
2080                                 /*
2081                                  * We only ensure valsize is not too large
2082                                  * here.  Further validation will be done
2083                                  * later.
2084                                  */
2085                                 error = sooptcopyin(sopt, optbuf_storage,
2086                                     sizeof(optbuf_storage), 0);
2087                                 if (error)
2088                                         break;
2089                                 optlen = sopt->sopt_valsize;
2090                                 optbuf = optbuf_storage;
2091                                 INP_WLOCK(inp);
2092                                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
2093                                         INP_WUNLOCK(inp);
2094                                         return (ECONNRESET);
2095                                 }
2096                                 optp = &inp->in6p_outputopts;
2097                                 error = ip6_pcbopt(optname, optbuf, optlen,
2098                                     optp, (td != NULL) ? td->td_ucred : NULL,
2099                                     uproto);
2100                                 INP_WUNLOCK(inp);
2101                                 break;
2102                         }
2103 #undef OPTSET
2104
2105                         case IPV6_MULTICAST_IF:
2106                         case IPV6_MULTICAST_HOPS:
2107                         case IPV6_MULTICAST_LOOP:
2108                         case IPV6_JOIN_GROUP:
2109                         case IPV6_LEAVE_GROUP:
2110                         case IPV6_MSFILTER:
2111                         case MCAST_BLOCK_SOURCE:
2112                         case MCAST_UNBLOCK_SOURCE:
2113                         case MCAST_JOIN_GROUP:
2114                         case MCAST_LEAVE_GROUP:
2115                         case MCAST_JOIN_SOURCE_GROUP:
2116                         case MCAST_LEAVE_SOURCE_GROUP:
2117                                 error = ip6_setmoptions(inp, sopt);
2118                                 break;
2119
2120                         case IPV6_PORTRANGE:
2121                                 error = sooptcopyin(sopt, &optval,
2122                                     sizeof optval, sizeof optval);
2123                                 if (error)
2124                                         break;
2125
2126                                 INP_WLOCK(inp);
2127                                 switch (optval) {
2128                                 case IPV6_PORTRANGE_DEFAULT:
2129                                         inp->inp_flags &= ~(INP_LOWPORT);
2130                                         inp->inp_flags &= ~(INP_HIGHPORT);
2131                                         break;
2132
2133                                 case IPV6_PORTRANGE_HIGH:
2134                                         inp->inp_flags &= ~(INP_LOWPORT);
2135                                         inp->inp_flags |= INP_HIGHPORT;
2136                                         break;
2137
2138                                 case IPV6_PORTRANGE_LOW:
2139                                         inp->inp_flags &= ~(INP_HIGHPORT);
2140                                         inp->inp_flags |= INP_LOWPORT;
2141                                         break;
2142
2143                                 default:
2144                                         error = EINVAL;
2145                                         break;
2146                                 }
2147                                 INP_WUNLOCK(inp);
2148                                 break;
2149
2150 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2151                         case IPV6_IPSEC_POLICY:
2152                                 if (IPSEC_ENABLED(ipv6)) {
2153                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2154                                         break;
2155                                 }
2156                                 /* FALLTHROUGH */
2157 #endif /* IPSEC */
2158
2159                         default:
2160                                 error = ENOPROTOOPT;
2161                                 break;
2162                         }
2163                         break;
2164
2165                 case SOPT_GET:
2166                         switch (optname) {
2167                         case IPV6_2292PKTOPTIONS:
2168 #ifdef IPV6_PKTOPTIONS
2169                         case IPV6_PKTOPTIONS:
2170 #endif
2171                                 /*
2172                                  * RFC3542 (effectively) deprecated the
2173                                  * semantics of the 2292-style pktoptions.
2174                                  * Since it was not reliable in nature (i.e.,
2175                                  * applications had to expect the lack of some
2176                                  * information after all), it would make sense
2177                                  * to simplify this part by always returning
2178                                  * empty data.
2179                                  */
2180                                 sopt->sopt_valsize = 0;
2181                                 break;
2182
2183                         case IPV6_RECVHOPOPTS:
2184                         case IPV6_RECVDSTOPTS:
2185                         case IPV6_RECVRTHDRDSTOPTS:
2186                         case IPV6_UNICAST_HOPS:
2187                         case IPV6_RECVPKTINFO:
2188                         case IPV6_RECVHOPLIMIT:
2189                         case IPV6_RECVRTHDR:
2190                         case IPV6_RECVPATHMTU:
2191
2192                         case IPV6_V6ONLY:
2193                         case IPV6_PORTRANGE:
2194                         case IPV6_RECVTCLASS:
2195                         case IPV6_AUTOFLOWLABEL:
2196                         case IPV6_BINDANY:
2197                         case IPV6_FLOWID:
2198                         case IPV6_FLOWTYPE:
2199                         case IPV6_RECVFLOWID:
2200 #ifdef  RSS
2201                         case IPV6_RSSBUCKETID:
2202                         case IPV6_RECVRSSBUCKETID:
2203 #endif
2204                         case IPV6_BINDMULTI:
2205                         case IPV6_VLAN_PCP:
2206                                 switch (optname) {
2207                                 case IPV6_RECVHOPOPTS:
2208                                         optval = OPTBIT(IN6P_HOPOPTS);
2209                                         break;
2210
2211                                 case IPV6_RECVDSTOPTS:
2212                                         optval = OPTBIT(IN6P_DSTOPTS);
2213                                         break;
2214
2215                                 case IPV6_RECVRTHDRDSTOPTS:
2216                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2217                                         break;
2218
2219                                 case IPV6_UNICAST_HOPS:
2220                                         optval = inp->in6p_hops;
2221                                         break;
2222
2223                                 case IPV6_RECVPKTINFO:
2224                                         optval = OPTBIT(IN6P_PKTINFO);
2225                                         break;
2226
2227                                 case IPV6_RECVHOPLIMIT:
2228                                         optval = OPTBIT(IN6P_HOPLIMIT);
2229                                         break;
2230
2231                                 case IPV6_RECVRTHDR:
2232                                         optval = OPTBIT(IN6P_RTHDR);
2233                                         break;
2234
2235                                 case IPV6_RECVPATHMTU:
2236                                         optval = OPTBIT(IN6P_MTU);
2237                                         break;
2238
2239                                 case IPV6_V6ONLY:
2240                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2241                                         break;
2242
2243                                 case IPV6_PORTRANGE:
2244                                     {
2245                                         int flags;
2246                                         flags = inp->inp_flags;
2247                                         if (flags & INP_HIGHPORT)
2248                                                 optval = IPV6_PORTRANGE_HIGH;
2249                                         else if (flags & INP_LOWPORT)
2250                                                 optval = IPV6_PORTRANGE_LOW;
2251                                         else
2252                                                 optval = 0;
2253                                         break;
2254                                     }
2255                                 case IPV6_RECVTCLASS:
2256                                         optval = OPTBIT(IN6P_TCLASS);
2257                                         break;
2258
2259                                 case IPV6_AUTOFLOWLABEL:
2260                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2261                                         break;
2262
2263                                 case IPV6_ORIGDSTADDR:
2264                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2265                                         break;
2266
2267                                 case IPV6_BINDANY:
2268                                         optval = OPTBIT(INP_BINDANY);
2269                                         break;
2270
2271                                 case IPV6_FLOWID:
2272                                         optval = inp->inp_flowid;
2273                                         break;
2274
2275                                 case IPV6_FLOWTYPE:
2276                                         optval = inp->inp_flowtype;
2277                                         break;
2278
2279                                 case IPV6_RECVFLOWID:
2280                                         optval = OPTBIT2(INP_RECVFLOWID);
2281                                         break;
2282 #ifdef  RSS
2283                                 case IPV6_RSSBUCKETID:
2284                                         retval =
2285                                             rss_hash2bucket(inp->inp_flowid,
2286                                             inp->inp_flowtype,
2287                                             &rss_bucket);
2288                                         if (retval == 0)
2289                                                 optval = rss_bucket;
2290                                         else
2291                                                 error = EINVAL;
2292                                         break;
2293
2294                                 case IPV6_RECVRSSBUCKETID:
2295                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2296                                         break;
2297 #endif
2298
2299                                 case IPV6_BINDMULTI:
2300                                         optval = OPTBIT2(INP_BINDMULTI);
2301                                         break;
2302
2303                                 case IPV6_VLAN_PCP:
2304                                         if (OPTBIT2(INP_2PCP_SET)) {
2305                                                 optval = (inp->inp_flags2 &
2306                                                             INP_2PCP_MASK) >>
2307                                                             INP_2PCP_SHIFT;
2308                                         } else {
2309                                                 optval = -1;
2310                                         }
2311                                         break;
2312                                 }
2313
2314                                 if (error)
2315                                         break;
2316                                 error = sooptcopyout(sopt, &optval,
2317                                         sizeof optval);
2318                                 break;
2319
2320                         case IPV6_PATHMTU:
2321                         {
2322                                 u_long pmtu = 0;
2323                                 struct ip6_mtuinfo mtuinfo;
2324                                 struct in6_addr addr;
2325
2326                                 if (!(so->so_state & SS_ISCONNECTED))
2327                                         return (ENOTCONN);
2328                                 /*
2329                                  * XXX: we dot not consider the case of source
2330                                  * routing, or optional information to specify
2331                                  * the outgoing interface.
2332                                  * Copy faddr out of inp to avoid holding lock
2333                                  * on inp during route lookup.
2334                                  */
2335                                 INP_RLOCK(inp);
2336                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2337                                 INP_RUNLOCK(inp);
2338                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2339                                     &addr, &pmtu);
2340                                 if (error)
2341                                         break;
2342                                 if (pmtu > IPV6_MAXPACKET)
2343                                         pmtu = IPV6_MAXPACKET;
2344
2345                                 bzero(&mtuinfo, sizeof(mtuinfo));
2346                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2347                                 optdata = (void *)&mtuinfo;
2348                                 optdatalen = sizeof(mtuinfo);
2349                                 error = sooptcopyout(sopt, optdata,
2350                                     optdatalen);
2351                                 break;
2352                         }
2353
2354                         case IPV6_2292PKTINFO:
2355                         case IPV6_2292HOPLIMIT:
2356                         case IPV6_2292HOPOPTS:
2357                         case IPV6_2292RTHDR:
2358                         case IPV6_2292DSTOPTS:
2359                                 switch (optname) {
2360                                 case IPV6_2292PKTINFO:
2361                                         optval = OPTBIT(IN6P_PKTINFO);
2362                                         break;
2363                                 case IPV6_2292HOPLIMIT:
2364                                         optval = OPTBIT(IN6P_HOPLIMIT);
2365                                         break;
2366                                 case IPV6_2292HOPOPTS:
2367                                         optval = OPTBIT(IN6P_HOPOPTS);
2368                                         break;
2369                                 case IPV6_2292RTHDR:
2370                                         optval = OPTBIT(IN6P_RTHDR);
2371                                         break;
2372                                 case IPV6_2292DSTOPTS:
2373                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2374                                         break;
2375                                 }
2376                                 error = sooptcopyout(sopt, &optval,
2377                                     sizeof optval);
2378                                 break;
2379                         case IPV6_PKTINFO:
2380                         case IPV6_HOPOPTS:
2381                         case IPV6_RTHDR:
2382                         case IPV6_DSTOPTS:
2383                         case IPV6_RTHDRDSTOPTS:
2384                         case IPV6_NEXTHOP:
2385                         case IPV6_TCLASS:
2386                         case IPV6_DONTFRAG:
2387                         case IPV6_USE_MIN_MTU:
2388                         case IPV6_PREFER_TEMPADDR:
2389                                 error = ip6_getpcbopt(inp, optname, sopt);
2390                                 break;
2391
2392                         case IPV6_MULTICAST_IF:
2393                         case IPV6_MULTICAST_HOPS:
2394                         case IPV6_MULTICAST_LOOP:
2395                         case IPV6_MSFILTER:
2396                                 error = ip6_getmoptions(inp, sopt);
2397                                 break;
2398
2399 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2400                         case IPV6_IPSEC_POLICY:
2401                                 if (IPSEC_ENABLED(ipv6)) {
2402                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2403                                         break;
2404                                 }
2405                                 /* FALLTHROUGH */
2406 #endif /* IPSEC */
2407                         default:
2408                                 error = ENOPROTOOPT;
2409                                 break;
2410                         }
2411                         break;
2412                 }
2413         }
2414         return (error);
2415 }
2416
2417 int
2418 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2419 {
2420         int error = 0, optval, optlen;
2421         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2422         struct inpcb *inp = sotoinpcb(so);
2423         int level, op, optname;
2424
2425         level = sopt->sopt_level;
2426         op = sopt->sopt_dir;
2427         optname = sopt->sopt_name;
2428         optlen = sopt->sopt_valsize;
2429
2430         if (level != IPPROTO_IPV6) {
2431                 return (EINVAL);
2432         }
2433
2434         switch (optname) {
2435         case IPV6_CHECKSUM:
2436                 /*
2437                  * For ICMPv6 sockets, no modification allowed for checksum
2438                  * offset, permit "no change" values to help existing apps.
2439                  *
2440                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2441                  * for an ICMPv6 socket will fail."
2442                  * The current behavior does not meet RFC3542.
2443                  */
2444                 switch (op) {
2445                 case SOPT_SET:
2446                         if (optlen != sizeof(int)) {
2447                                 error = EINVAL;
2448                                 break;
2449                         }
2450                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2451                                             sizeof(optval));
2452                         if (error)
2453                                 break;
2454                         if (optval < -1 || (optval % 2) != 0) {
2455                                 /*
2456                                  * The API assumes non-negative even offset
2457                                  * values or -1 as a special value.
2458                                  */
2459                                 error = EINVAL;
2460                         } else if (so->so_proto->pr_protocol ==
2461                             IPPROTO_ICMPV6) {
2462                                 if (optval != icmp6off)
2463                                         error = EINVAL;
2464                         } else
2465                                 inp->in6p_cksum = optval;
2466                         break;
2467
2468                 case SOPT_GET:
2469                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2470                                 optval = icmp6off;
2471                         else
2472                                 optval = inp->in6p_cksum;
2473
2474                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2475                         break;
2476
2477                 default:
2478                         error = EINVAL;
2479                         break;
2480                 }
2481                 break;
2482
2483         default:
2484                 error = ENOPROTOOPT;
2485                 break;
2486         }
2487
2488         return (error);
2489 }
2490
2491 /*
2492  * Set up IP6 options in pcb for insertion in output packets or
2493  * specifying behavior of outgoing packets.
2494  */
2495 static int
2496 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2497     struct socket *so, struct sockopt *sopt)
2498 {
2499         struct ip6_pktopts *opt = *pktopt;
2500         int error = 0;
2501         struct thread *td = sopt->sopt_td;
2502
2503         /* turn off any old options. */
2504         if (opt) {
2505 #ifdef DIAGNOSTIC
2506                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2507                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2508                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2509                         printf("ip6_pcbopts: all specified options are cleared.\n");
2510 #endif
2511                 ip6_clearpktopts(opt, -1);
2512         } else {
2513                 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT);
2514                 if (opt == NULL)
2515                         return (ENOMEM);
2516         }
2517         *pktopt = NULL;
2518
2519         if (!m || m->m_len == 0) {
2520                 /*
2521                  * Only turning off any previous options, regardless of
2522                  * whether the opt is just created or given.
2523                  */
2524                 free(opt, M_IP6OPT);
2525                 return (0);
2526         }
2527
2528         /*  set options specified by user. */
2529         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2530             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2531                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2532                 free(opt, M_IP6OPT);
2533                 return (error);
2534         }
2535         *pktopt = opt;
2536         return (0);
2537 }
2538
2539 /*
2540  * initialize ip6_pktopts.  beware that there are non-zero default values in
2541  * the struct.
2542  */
2543 void
2544 ip6_initpktopts(struct ip6_pktopts *opt)
2545 {
2546
2547         bzero(opt, sizeof(*opt));
2548         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2549         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2550         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2551         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2552 }
2553
2554 static int
2555 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2556     struct ucred *cred, int uproto)
2557 {
2558         struct ip6_pktopts *opt;
2559
2560         if (*pktopt == NULL) {
2561                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2562                     M_NOWAIT);
2563                 if (*pktopt == NULL)
2564                         return (ENOBUFS);
2565                 ip6_initpktopts(*pktopt);
2566         }
2567         opt = *pktopt;
2568
2569         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2570 }
2571
2572 #define GET_PKTOPT_VAR(field, lenexpr) do {                                     \
2573         if (pktopt && pktopt->field) {                                          \
2574                 INP_RUNLOCK(inp);                                               \
2575                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK);         \
2576                 malloc_optdata = true;                                          \
2577                 INP_RLOCK(inp);                                                 \
2578                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {            \
2579                         INP_RUNLOCK(inp);                                       \
2580                         free(optdata, M_TEMP);                                  \
2581                         return (ECONNRESET);                                    \
2582                 }                                                               \
2583                 pktopt = inp->in6p_outputopts;                                  \
2584                 if (pktopt && pktopt->field) {                                  \
2585                         optdatalen = min(lenexpr, sopt->sopt_valsize);          \
2586                         bcopy(&pktopt->field, optdata, optdatalen);             \
2587                 } else {                                                        \
2588                         free(optdata, M_TEMP);                                  \
2589                         optdata = NULL;                                         \
2590                         malloc_optdata = false;                                 \
2591                 }                                                               \
2592         }                                                                       \
2593 } while(0)
2594
2595 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                         \
2596         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2597
2598 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                        \
2599         pktopt->field->sa_len)
2600
2601 static int
2602 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2603 {
2604         void *optdata = NULL;
2605         bool malloc_optdata = false;
2606         int optdatalen = 0;
2607         int error = 0;
2608         struct in6_pktinfo null_pktinfo;
2609         int deftclass = 0, on;
2610         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2611         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2612         struct ip6_pktopts *pktopt;
2613
2614         INP_RLOCK(inp);
2615         pktopt = inp->in6p_outputopts;
2616
2617         switch (optname) {
2618         case IPV6_PKTINFO:
2619                 optdata = (void *)&null_pktinfo;
2620                 if (pktopt && pktopt->ip6po_pktinfo) {
2621                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2622                             sizeof(null_pktinfo));
2623                         in6_clearscope(&null_pktinfo.ipi6_addr);
2624                 } else {
2625                         /* XXX: we don't have to do this every time... */
2626                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2627                 }
2628                 optdatalen = sizeof(struct in6_pktinfo);
2629                 break;
2630         case IPV6_TCLASS:
2631                 if (pktopt && pktopt->ip6po_tclass >= 0)
2632                         deftclass = pktopt->ip6po_tclass;
2633                 optdata = (void *)&deftclass;
2634                 optdatalen = sizeof(int);
2635                 break;
2636         case IPV6_HOPOPTS:
2637                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2638                 break;
2639         case IPV6_RTHDR:
2640                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2641                 break;
2642         case IPV6_RTHDRDSTOPTS:
2643                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2644                 break;
2645         case IPV6_DSTOPTS:
2646                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2647                 break;
2648         case IPV6_NEXTHOP:
2649                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2650                 break;
2651         case IPV6_USE_MIN_MTU:
2652                 if (pktopt)
2653                         defminmtu = pktopt->ip6po_minmtu;
2654                 optdata = (void *)&defminmtu;
2655                 optdatalen = sizeof(int);
2656                 break;
2657         case IPV6_DONTFRAG:
2658                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2659                         on = 1;
2660                 else
2661                         on = 0;
2662                 optdata = (void *)&on;
2663                 optdatalen = sizeof(on);
2664                 break;
2665         case IPV6_PREFER_TEMPADDR:
2666                 if (pktopt)
2667                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2668                 optdata = (void *)&defpreftemp;
2669                 optdatalen = sizeof(int);
2670                 break;
2671         default:                /* should not happen */
2672 #ifdef DIAGNOSTIC
2673                 panic("ip6_getpcbopt: unexpected option\n");
2674 #endif
2675                 INP_RUNLOCK(inp);
2676                 return (ENOPROTOOPT);
2677         }
2678         INP_RUNLOCK(inp);
2679
2680         error = sooptcopyout(sopt, optdata, optdatalen);
2681         if (malloc_optdata)
2682                 free(optdata, M_TEMP);
2683
2684         return (error);
2685 }
2686
2687 void
2688 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2689 {
2690         if (pktopt == NULL)
2691                 return;
2692
2693         if (optname == -1 || optname == IPV6_PKTINFO) {
2694                 if (pktopt->ip6po_pktinfo)
2695                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2696                 pktopt->ip6po_pktinfo = NULL;
2697         }
2698         if (optname == -1 || optname == IPV6_HOPLIMIT)
2699                 pktopt->ip6po_hlim = -1;
2700         if (optname == -1 || optname == IPV6_TCLASS)
2701                 pktopt->ip6po_tclass = -1;
2702         if (optname == -1 || optname == IPV6_NEXTHOP) {
2703                 if (pktopt->ip6po_nextroute.ro_nh) {
2704                         NH_FREE(pktopt->ip6po_nextroute.ro_nh);
2705                         pktopt->ip6po_nextroute.ro_nh = NULL;
2706                 }
2707                 if (pktopt->ip6po_nexthop)
2708                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2709                 pktopt->ip6po_nexthop = NULL;
2710         }
2711         if (optname == -1 || optname == IPV6_HOPOPTS) {
2712                 if (pktopt->ip6po_hbh)
2713                         free(pktopt->ip6po_hbh, M_IP6OPT);
2714                 pktopt->ip6po_hbh = NULL;
2715         }
2716         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2717                 if (pktopt->ip6po_dest1)
2718                         free(pktopt->ip6po_dest1, M_IP6OPT);
2719                 pktopt->ip6po_dest1 = NULL;
2720         }
2721         if (optname == -1 || optname == IPV6_RTHDR) {
2722                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2723                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2724                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2725                 if (pktopt->ip6po_route.ro_nh) {
2726                         NH_FREE(pktopt->ip6po_route.ro_nh);
2727                         pktopt->ip6po_route.ro_nh = NULL;
2728                 }
2729         }
2730         if (optname == -1 || optname == IPV6_DSTOPTS) {
2731                 if (pktopt->ip6po_dest2)
2732                         free(pktopt->ip6po_dest2, M_IP6OPT);
2733                 pktopt->ip6po_dest2 = NULL;
2734         }
2735 }
2736
2737 #define PKTOPT_EXTHDRCPY(type) \
2738 do {\
2739         if (src->type) {\
2740                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2741                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2742                 if (dst->type == NULL)\
2743                         goto bad;\
2744                 bcopy(src->type, dst->type, hlen);\
2745         }\
2746 } while (/*CONSTCOND*/ 0)
2747
2748 static int
2749 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2750 {
2751         if (dst == NULL || src == NULL)  {
2752                 printf("ip6_clearpktopts: invalid argument\n");
2753                 return (EINVAL);
2754         }
2755
2756         dst->ip6po_hlim = src->ip6po_hlim;
2757         dst->ip6po_tclass = src->ip6po_tclass;
2758         dst->ip6po_flags = src->ip6po_flags;
2759         dst->ip6po_minmtu = src->ip6po_minmtu;
2760         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2761         if (src->ip6po_pktinfo) {
2762                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2763                     M_IP6OPT, canwait);
2764                 if (dst->ip6po_pktinfo == NULL)
2765                         goto bad;
2766                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2767         }
2768         if (src->ip6po_nexthop) {
2769                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2770                     M_IP6OPT, canwait);
2771                 if (dst->ip6po_nexthop == NULL)
2772                         goto bad;
2773                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2774                     src->ip6po_nexthop->sa_len);
2775         }
2776         PKTOPT_EXTHDRCPY(ip6po_hbh);
2777         PKTOPT_EXTHDRCPY(ip6po_dest1);
2778         PKTOPT_EXTHDRCPY(ip6po_dest2);
2779         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2780         return (0);
2781
2782   bad:
2783         ip6_clearpktopts(dst, -1);
2784         return (ENOBUFS);
2785 }
2786 #undef PKTOPT_EXTHDRCPY
2787
2788 struct ip6_pktopts *
2789 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2790 {
2791         int error;
2792         struct ip6_pktopts *dst;
2793
2794         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2795         if (dst == NULL)
2796                 return (NULL);
2797         ip6_initpktopts(dst);
2798
2799         if ((error = copypktopts(dst, src, canwait)) != 0) {
2800                 free(dst, M_IP6OPT);
2801                 return (NULL);
2802         }
2803
2804         return (dst);
2805 }
2806
2807 void
2808 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2809 {
2810         if (pktopt == NULL)
2811                 return;
2812
2813         ip6_clearpktopts(pktopt, -1);
2814
2815         free(pktopt, M_IP6OPT);
2816 }
2817
2818 /*
2819  * Set IPv6 outgoing packet options based on advanced API.
2820  */
2821 int
2822 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2823     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2824 {
2825         struct cmsghdr *cm = NULL;
2826
2827         if (control == NULL || opt == NULL)
2828                 return (EINVAL);
2829
2830         ip6_initpktopts(opt);
2831         if (stickyopt) {
2832                 int error;
2833
2834                 /*
2835                  * If stickyopt is provided, make a local copy of the options
2836                  * for this particular packet, then override them by ancillary
2837                  * objects.
2838                  * XXX: copypktopts() does not copy the cached route to a next
2839                  * hop (if any).  This is not very good in terms of efficiency,
2840                  * but we can allow this since this option should be rarely
2841                  * used.
2842                  */
2843                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2844                         return (error);
2845         }
2846
2847         /*
2848          * XXX: Currently, we assume all the optional information is stored
2849          * in a single mbuf.
2850          */
2851         if (control->m_next)
2852                 return (EINVAL);
2853
2854         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2855             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2856                 int error;
2857
2858                 if (control->m_len < CMSG_LEN(0))
2859                         return (EINVAL);
2860
2861                 cm = mtod(control, struct cmsghdr *);
2862                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2863                         return (EINVAL);
2864                 if (cm->cmsg_level != IPPROTO_IPV6)
2865                         continue;
2866
2867                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2868                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2869                 if (error)
2870                         return (error);
2871         }
2872
2873         return (0);
2874 }
2875
2876 /*
2877  * Set a particular packet option, as a sticky option or an ancillary data
2878  * item.  "len" can be 0 only when it's a sticky option.
2879  * We have 4 cases of combination of "sticky" and "cmsg":
2880  * "sticky=0, cmsg=0": impossible
2881  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2882  * "sticky=1, cmsg=0": RFC3542 socket option
2883  * "sticky=1, cmsg=1": RFC2292 socket option
2884  */
2885 static int
2886 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2887     struct ucred *cred, int sticky, int cmsg, int uproto)
2888 {
2889         int minmtupolicy, preftemp;
2890         int error;
2891
2892         if (!sticky && !cmsg) {
2893 #ifdef DIAGNOSTIC
2894                 printf("ip6_setpktopt: impossible case\n");
2895 #endif
2896                 return (EINVAL);
2897         }
2898
2899         /*
2900          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2901          * not be specified in the context of RFC3542.  Conversely,
2902          * RFC3542 types should not be specified in the context of RFC2292.
2903          */
2904         if (!cmsg) {
2905                 switch (optname) {
2906                 case IPV6_2292PKTINFO:
2907                 case IPV6_2292HOPLIMIT:
2908                 case IPV6_2292NEXTHOP:
2909                 case IPV6_2292HOPOPTS:
2910                 case IPV6_2292DSTOPTS:
2911                 case IPV6_2292RTHDR:
2912                 case IPV6_2292PKTOPTIONS:
2913                         return (ENOPROTOOPT);
2914                 }
2915         }
2916         if (sticky && cmsg) {
2917                 switch (optname) {
2918                 case IPV6_PKTINFO:
2919                 case IPV6_HOPLIMIT:
2920                 case IPV6_NEXTHOP:
2921                 case IPV6_HOPOPTS:
2922                 case IPV6_DSTOPTS:
2923                 case IPV6_RTHDRDSTOPTS:
2924                 case IPV6_RTHDR:
2925                 case IPV6_USE_MIN_MTU:
2926                 case IPV6_DONTFRAG:
2927                 case IPV6_TCLASS:
2928                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2929                         return (ENOPROTOOPT);
2930                 }
2931         }
2932
2933         switch (optname) {
2934         case IPV6_2292PKTINFO:
2935         case IPV6_PKTINFO:
2936         {
2937                 struct ifnet *ifp = NULL;
2938                 struct in6_pktinfo *pktinfo;
2939
2940                 if (len != sizeof(struct in6_pktinfo))
2941                         return (EINVAL);
2942
2943                 pktinfo = (struct in6_pktinfo *)buf;
2944
2945                 /*
2946                  * An application can clear any sticky IPV6_PKTINFO option by
2947                  * doing a "regular" setsockopt with ipi6_addr being
2948                  * in6addr_any and ipi6_ifindex being zero.
2949                  * [RFC 3542, Section 6]
2950                  */
2951                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2952                     pktinfo->ipi6_ifindex == 0 &&
2953                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2954                         ip6_clearpktopts(opt, optname);
2955                         break;
2956                 }
2957
2958                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2959                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2960                         return (EINVAL);
2961                 }
2962                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2963                         return (EINVAL);
2964                 /* validate the interface index if specified. */
2965                 if (pktinfo->ipi6_ifindex > V_if_index)
2966                          return (ENXIO);
2967                 if (pktinfo->ipi6_ifindex) {
2968                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2969                         if (ifp == NULL)
2970                                 return (ENXIO);
2971                 }
2972                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2973                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2974                         return (ENETDOWN);
2975
2976                 if (ifp != NULL &&
2977                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2978                         struct in6_ifaddr *ia;
2979
2980                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2981                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2982                         if (ia == NULL)
2983                                 return (EADDRNOTAVAIL);
2984                         ifa_free(&ia->ia_ifa);
2985                 }
2986                 /*
2987                  * We store the address anyway, and let in6_selectsrc()
2988                  * validate the specified address.  This is because ipi6_addr
2989                  * may not have enough information about its scope zone, and
2990                  * we may need additional information (such as outgoing
2991                  * interface or the scope zone of a destination address) to
2992                  * disambiguate the scope.
2993                  * XXX: the delay of the validation may confuse the
2994                  * application when it is used as a sticky option.
2995                  */
2996                 if (opt->ip6po_pktinfo == NULL) {
2997                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2998                             M_IP6OPT, M_NOWAIT);
2999                         if (opt->ip6po_pktinfo == NULL)
3000                                 return (ENOBUFS);
3001                 }
3002                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
3003                 break;
3004         }
3005
3006         case IPV6_2292HOPLIMIT:
3007         case IPV6_HOPLIMIT:
3008         {
3009                 int *hlimp;
3010
3011                 /*
3012                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
3013                  * to simplify the ordering among hoplimit options.
3014                  */
3015                 if (optname == IPV6_HOPLIMIT && sticky)
3016                         return (ENOPROTOOPT);
3017
3018                 if (len != sizeof(int))
3019                         return (EINVAL);
3020                 hlimp = (int *)buf;
3021                 if (*hlimp < -1 || *hlimp > 255)
3022                         return (EINVAL);
3023
3024                 opt->ip6po_hlim = *hlimp;
3025                 break;
3026         }
3027
3028         case IPV6_TCLASS:
3029         {
3030                 int tclass;
3031
3032                 if (len != sizeof(int))
3033                         return (EINVAL);
3034                 tclass = *(int *)buf;
3035                 if (tclass < -1 || tclass > 255)
3036                         return (EINVAL);
3037
3038                 opt->ip6po_tclass = tclass;
3039                 break;
3040         }
3041
3042         case IPV6_2292NEXTHOP:
3043         case IPV6_NEXTHOP:
3044                 if (cred != NULL) {
3045                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3046                         if (error)
3047                                 return (error);
3048                 }
3049
3050                 if (len == 0) { /* just remove the option */
3051                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
3052                         break;
3053                 }
3054
3055                 /* check if cmsg_len is large enough for sa_len */
3056                 if (len < sizeof(struct sockaddr) || len < *buf)
3057                         return (EINVAL);
3058
3059                 switch (((struct sockaddr *)buf)->sa_family) {
3060                 case AF_INET6:
3061                 {
3062                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
3063                         int error;
3064
3065                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
3066                                 return (EINVAL);
3067
3068                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
3069                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
3070                                 return (EINVAL);
3071                         }
3072                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
3073                             != 0) {
3074                                 return (error);
3075                         }
3076                         break;
3077                 }
3078                 case AF_LINK:   /* should eventually be supported */
3079                 default:
3080                         return (EAFNOSUPPORT);
3081                 }
3082
3083                 /* turn off the previous option, then set the new option. */
3084                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
3085                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
3086                 if (opt->ip6po_nexthop == NULL)
3087                         return (ENOBUFS);
3088                 bcopy(buf, opt->ip6po_nexthop, *buf);
3089                 break;
3090
3091         case IPV6_2292HOPOPTS:
3092         case IPV6_HOPOPTS:
3093         {
3094                 struct ip6_hbh *hbh;
3095                 int hbhlen;
3096
3097                 /*
3098                  * XXX: We don't allow a non-privileged user to set ANY HbH
3099                  * options, since per-option restriction has too much
3100                  * overhead.
3101                  */
3102                 if (cred != NULL) {
3103                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3104                         if (error)
3105                                 return (error);
3106                 }
3107
3108                 if (len == 0) {
3109                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
3110                         break;  /* just remove the option */
3111                 }
3112
3113                 /* message length validation */
3114                 if (len < sizeof(struct ip6_hbh))
3115                         return (EINVAL);
3116                 hbh = (struct ip6_hbh *)buf;
3117                 hbhlen = (hbh->ip6h_len + 1) << 3;
3118                 if (len != hbhlen)
3119                         return (EINVAL);
3120
3121                 /* turn off the previous option, then set the new option. */
3122                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
3123                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
3124                 if (opt->ip6po_hbh == NULL)
3125                         return (ENOBUFS);
3126                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
3127
3128                 break;
3129         }
3130
3131         case IPV6_2292DSTOPTS:
3132         case IPV6_DSTOPTS:
3133         case IPV6_RTHDRDSTOPTS:
3134         {
3135                 struct ip6_dest *dest, **newdest = NULL;
3136                 int destlen;
3137
3138                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
3139                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3140                         if (error)
3141                                 return (error);
3142                 }
3143
3144                 if (len == 0) {
3145                         ip6_clearpktopts(opt, optname);
3146                         break;  /* just remove the option */
3147                 }
3148
3149                 /* message length validation */
3150                 if (len < sizeof(struct ip6_dest))
3151                         return (EINVAL);
3152                 dest = (struct ip6_dest *)buf;
3153                 destlen = (dest->ip6d_len + 1) << 3;
3154                 if (len != destlen)
3155                         return (EINVAL);
3156
3157                 /*
3158                  * Determine the position that the destination options header
3159                  * should be inserted; before or after the routing header.
3160                  */
3161                 switch (optname) {
3162                 case IPV6_2292DSTOPTS:
3163                         /*
3164                          * The old advacned API is ambiguous on this point.
3165                          * Our approach is to determine the position based
3166                          * according to the existence of a routing header.
3167                          * Note, however, that this depends on the order of the
3168                          * extension headers in the ancillary data; the 1st
3169                          * part of the destination options header must appear
3170                          * before the routing header in the ancillary data,
3171                          * too.
3172                          * RFC3542 solved the ambiguity by introducing
3173                          * separate ancillary data or option types.
3174                          */
3175                         if (opt->ip6po_rthdr == NULL)
3176                                 newdest = &opt->ip6po_dest1;
3177                         else
3178                                 newdest = &opt->ip6po_dest2;
3179                         break;
3180                 case IPV6_RTHDRDSTOPTS:
3181                         newdest = &opt->ip6po_dest1;
3182                         break;
3183                 case IPV6_DSTOPTS:
3184                         newdest = &opt->ip6po_dest2;
3185                         break;
3186                 }
3187
3188                 /* turn off the previous option, then set the new option. */
3189                 ip6_clearpktopts(opt, optname);
3190                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3191                 if (*newdest == NULL)
3192                         return (ENOBUFS);
3193                 bcopy(dest, *newdest, destlen);
3194
3195                 break;
3196         }
3197
3198         case IPV6_2292RTHDR:
3199         case IPV6_RTHDR:
3200         {
3201                 struct ip6_rthdr *rth;
3202                 int rthlen;
3203
3204                 if (len == 0) {
3205                         ip6_clearpktopts(opt, IPV6_RTHDR);
3206                         break;  /* just remove the option */
3207                 }
3208
3209                 /* message length validation */
3210                 if (len < sizeof(struct ip6_rthdr))
3211                         return (EINVAL);
3212                 rth = (struct ip6_rthdr *)buf;
3213                 rthlen = (rth->ip6r_len + 1) << 3;
3214                 if (len != rthlen)
3215                         return (EINVAL);
3216
3217                 switch (rth->ip6r_type) {
3218                 case IPV6_RTHDR_TYPE_0:
3219                         if (rth->ip6r_len == 0) /* must contain one addr */
3220                                 return (EINVAL);
3221                         if (rth->ip6r_len % 2) /* length must be even */
3222                                 return (EINVAL);
3223                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3224                                 return (EINVAL);
3225                         break;
3226                 default:
3227                         return (EINVAL);        /* not supported */
3228                 }
3229
3230                 /* turn off the previous option */
3231                 ip6_clearpktopts(opt, IPV6_RTHDR);
3232                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3233                 if (opt->ip6po_rthdr == NULL)
3234                         return (ENOBUFS);
3235                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3236
3237                 break;
3238         }
3239
3240         case IPV6_USE_MIN_MTU:
3241                 if (len != sizeof(int))
3242                         return (EINVAL);
3243                 minmtupolicy = *(int *)buf;
3244                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3245                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3246                     minmtupolicy != IP6PO_MINMTU_ALL) {
3247                         return (EINVAL);
3248                 }
3249                 opt->ip6po_minmtu = minmtupolicy;
3250                 break;
3251
3252         case IPV6_DONTFRAG:
3253                 if (len != sizeof(int))
3254                         return (EINVAL);
3255
3256                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3257                         /*
3258                          * we ignore this option for TCP sockets.
3259                          * (RFC3542 leaves this case unspecified.)
3260                          */
3261                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3262                 } else
3263                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3264                 break;
3265
3266         case IPV6_PREFER_TEMPADDR:
3267                 if (len != sizeof(int))
3268                         return (EINVAL);
3269                 preftemp = *(int *)buf;
3270                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3271                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3272                     preftemp != IP6PO_TEMPADDR_PREFER) {
3273                         return (EINVAL);
3274                 }
3275                 opt->ip6po_prefer_tempaddr = preftemp;
3276                 break;
3277
3278         default:
3279                 return (ENOPROTOOPT);
3280         } /* end of switch */
3281
3282         return (0);
3283 }
3284
3285 /*
3286  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3287  * packet to the input queue of a specified interface.  Note that this
3288  * calls the output routine of the loopback "driver", but with an interface
3289  * pointer that might NOT be &loif -- easier than replicating that code here.
3290  */
3291 void
3292 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3293 {
3294         struct mbuf *copym;
3295         struct ip6_hdr *ip6;
3296
3297         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3298         if (copym == NULL)
3299                 return;
3300
3301         /*
3302          * Make sure to deep-copy IPv6 header portion in case the data
3303          * is in an mbuf cluster, so that we can safely override the IPv6
3304          * header portion later.
3305          */
3306         if (!M_WRITABLE(copym) ||
3307             copym->m_len < sizeof(struct ip6_hdr)) {
3308                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3309                 if (copym == NULL)
3310                         return;
3311         }
3312         ip6 = mtod(copym, struct ip6_hdr *);
3313         /*
3314          * clear embedded scope identifiers if necessary.
3315          * in6_clearscope will touch the addresses only when necessary.
3316          */
3317         in6_clearscope(&ip6->ip6_src);
3318         in6_clearscope(&ip6->ip6_dst);
3319         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3320                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3321                     CSUM_PSEUDO_HDR;
3322                 copym->m_pkthdr.csum_data = 0xffff;
3323         }
3324         if_simloop(ifp, copym, AF_INET6, 0);
3325 }
3326
3327 /*
3328  * Chop IPv6 header off from the payload.
3329  */
3330 static int
3331 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3332 {
3333         struct mbuf *mh;
3334         struct ip6_hdr *ip6;
3335
3336         ip6 = mtod(m, struct ip6_hdr *);
3337         if (m->m_len > sizeof(*ip6)) {
3338                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3339                 if (mh == NULL) {
3340                         m_freem(m);
3341                         return ENOBUFS;
3342                 }
3343                 m_move_pkthdr(mh, m);
3344                 M_ALIGN(mh, sizeof(*ip6));
3345                 m->m_len -= sizeof(*ip6);
3346                 m->m_data += sizeof(*ip6);
3347                 mh->m_next = m;
3348                 m = mh;
3349                 m->m_len = sizeof(*ip6);
3350                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3351         }
3352         exthdrs->ip6e_ip6 = m;
3353         return 0;
3354 }
3355
3356 /*
3357  * Compute IPv6 extension header length.
3358  */
3359 int
3360 ip6_optlen(struct inpcb *inp)
3361 {
3362         int len;
3363
3364         if (!inp->in6p_outputopts)
3365                 return 0;
3366
3367         len = 0;
3368 #define elen(x) \
3369     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3370
3371         len += elen(inp->in6p_outputopts->ip6po_hbh);
3372         if (inp->in6p_outputopts->ip6po_rthdr)
3373                 /* dest1 is valid with rthdr only */
3374                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3375         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3376         len += elen(inp->in6p_outputopts->ip6po_dest2);
3377         return len;
3378 #undef elen
3379 }