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/scope6_var.h>
 125
 126 extern int in6_mcast_loop;
 127
 128 struct ip6_exthdrs {
 129         struct mbuf *ip6e_ip6;
 130         struct mbuf *ip6e_hbh;
 131         struct mbuf *ip6e_dest1;
 132         struct mbuf *ip6e_rthdr;
 133         struct mbuf *ip6e_dest2;
 134 };
 135
 136 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 137
 138 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 139                            struct ucred *, int);
 140 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 141         struct socket *, struct sockopt *);
 142 static int ip6_getpcbopt(struct inpcb *, int, struct sockopt *);
 143 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 144         struct ucred *, int, int, int);
 145
 146 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 147 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 148         struct ip6_frag **);
 149 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 150 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 151 static int ip6_getpmtu(struct route_in6 *, int,
 152         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int,
 153         u_int);
 154 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 155         u_long *, int *, u_int);
 156 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 157 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 158
 159 /*
 160  * Make an extension header from option data.  hp is the source,
 161  * mp is the destination, and _ol is the optlen.
 162  */
 163 #define MAKE_EXTHDR(hp, mp, _ol)                                        \
 164     do {                                                                \
 165         if (hp) {                                                       \
 166                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 167                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 168                     ((eh)->ip6e_len + 1) << 3);                         \
 169                 if (error)                                              \
 170                         goto freehdrs;                                  \
 171                 (_ol) += (*(mp))->m_len;                                \
 172         }                                                               \
 173     } while (/*CONSTCOND*/ 0)
 174
 175 /*
 176  * Form a chain of extension headers.
 177  * m is the extension header mbuf
 178  * mp is the previous mbuf in the chain
 179  * p is the next header
 180  * i is the type of option.
 181  */
 182 #define MAKE_CHAIN(m, mp, p, i)\
 183     do {\
 184         if (m) {\
 185                 if (!hdrsplit) \
 186                         panic("%s:%d: assumption failed: "\
 187                             "hdr not split: hdrsplit %d exthdrs %p",\
 188                             __func__, __LINE__, hdrsplit, &exthdrs);\
 189                 *mtod((m), u_char *) = *(p);\
 190                 *(p) = (i);\
 191                 p = mtod((m), u_char *);\
 192                 (m)->m_next = (mp)->m_next;\
 193                 (mp)->m_next = (m);\
 194                 (mp) = (m);\
 195         }\
 196     } while (/*CONSTCOND*/ 0)
 197
 198 void
 199 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 200 {
 201         u_short csum;
 202
 203         csum = in_cksum_skip(m, offset + plen, offset);
 204         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 205                 csum = 0xffff;
 206         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 207
 208         if (offset + sizeof(csum) > m->m_len)
 209                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
 210         else
 211                 *(u_short *)mtodo(m, offset) = csum;
 212 }
 213
 214 static void
 215 ip6_output_delayed_csum(struct mbuf *m, struct ifnet *ifp, int csum_flags,
 216     int plen, int optlen)
 217 {
 218
 219         KASSERT((plen >= optlen), ("%s:%d: plen %d < optlen %d, m %p, ifp %p "
 220             "csum_flags %#x",
 221             __func__, __LINE__, plen, optlen, m, ifp, csum_flags));
 222
 223         if (csum_flags & CSUM_DELAY_DATA_IPV6) {
 224                 in6_delayed_cksum(m, plen - optlen,
 225                     sizeof(struct ip6_hdr) + optlen);
 226                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 227         }
 228 #if defined(SCTP) || defined(SCTP_SUPPORT)
 229         if (csum_flags & CSUM_SCTP_IPV6) {
 230                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr) + optlen);
 231                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 232         }
 233 #endif
 234 }
 235
 236 int
 237 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 238     int fraglen , uint32_t id)
 239 {
 240         struct mbuf *m, **mnext, *m_frgpart;
 241         struct ip6_hdr *ip6, *mhip6;
 242         struct ip6_frag *ip6f;
 243         int off;
 244         int error;
 245         int tlen = m0->m_pkthdr.len;
 246
 247         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 248
 249         m = m0;
 250         ip6 = mtod(m, struct ip6_hdr *);
 251         mnext = &m->m_nextpkt;
 252
 253         for (off = hlen; off < tlen; off += fraglen) {
 254                 m = m_gethdr(M_NOWAIT, MT_DATA);
 255                 if (!m) {
 256                         IP6STAT_INC(ip6s_odropped);
 257                         return (ENOBUFS);
 258                 }
 259
 260                 /*
 261                  * Make sure the complete packet header gets copied
 262                  * from the originating mbuf to the newly created
 263                  * mbuf. This also ensures that existing firewall
 264                  * classification(s), VLAN tags and so on get copied
 265                  * to the resulting fragmented packet(s):
 266                  */
 267                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 268                         m_free(m);
 269                         IP6STAT_INC(ip6s_odropped);
 270                         return (ENOBUFS);
 271                 }
 272
 273                 *mnext = m;
 274                 mnext = &m->m_nextpkt;
 275                 m->m_data += max_linkhdr;
 276                 mhip6 = mtod(m, struct ip6_hdr *);
 277                 *mhip6 = *ip6;
 278                 m->m_len = sizeof(*mhip6);
 279                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 280                 if (error) {
 281                         IP6STAT_INC(ip6s_odropped);
 282                         return (error);
 283                 }
 284                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 285                 if (off + fraglen >= tlen)
 286                         fraglen = tlen - off;
 287                 else
 288                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 289                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 290                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 291                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 292                         IP6STAT_INC(ip6s_odropped);
 293                         return (ENOBUFS);
 294                 }
 295                 m_cat(m, m_frgpart);
 296                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 297                 ip6f->ip6f_reserved = 0;
 298                 ip6f->ip6f_ident = id;
 299                 ip6f->ip6f_nxt = nextproto;
 300                 IP6STAT_INC(ip6s_ofragments);
 301                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 302         }
 303
 304         return (0);
 305 }
 306
 307 static int
 308 ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp,
 309     struct mbuf *m, struct sockaddr_in6 *dst, struct route_in6 *ro,
 310     bool stamp_tag)
 311 {
 312 #ifdef KERN_TLS
 313         struct ktls_session *tls = NULL;
 314 #endif
 315         struct m_snd_tag *mst;
 316         int error;
 317
 318         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 319         mst = NULL;
 320
 321 #ifdef KERN_TLS
 322         /*
 323          * If this is an unencrypted TLS record, save a reference to
 324          * the record.  This local reference is used to call
 325          * ktls_output_eagain after the mbuf has been freed (thus
 326          * dropping the mbuf's reference) in if_output.
 327          */
 328         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 329                 tls = ktls_hold(m->m_next->m_epg_tls);
 330                 mst = tls->snd_tag;
 331
 332                 /*
 333                  * If a TLS session doesn't have a valid tag, it must
 334                  * have had an earlier ifp mismatch, so drop this
 335                  * packet.
 336                  */
 337                 if (mst == NULL) {
 338                         m_freem(m);
 339                         error = EAGAIN;
 340                         goto done;
 341                 }
 342                 /*
 343                  * Always stamp tags that include NIC ktls.
 344                  */
 345                 stamp_tag = true;
 346         }
 347 #endif
 348 #ifdef RATELIMIT
 349         if (inp != NULL && mst == NULL) {
 350                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 351                     (inp->inp_snd_tag != NULL &&
 352                     inp->inp_snd_tag->ifp != ifp))
 353                         in_pcboutput_txrtlmt(inp, ifp, m);
 354
 355                 if (inp->inp_snd_tag != NULL)
 356                         mst = inp->inp_snd_tag;
 357         }
 358 #endif
 359         if (stamp_tag && mst != NULL) {
 360                 KASSERT(m->m_pkthdr.rcvif == NULL,
 361                     ("trying to add a send tag to a forwarded packet"));
 362                 if (mst->ifp != ifp) {
 363                         m_freem(m);
 364                         error = EAGAIN;
 365                         goto done;
 366                 }
 367
 368                 /* stamp send tag on mbuf */
 369                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 370                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 371         }
 372
 373         error = nd6_output_ifp(ifp, origifp, m, dst, (struct route *)ro);
 374
 375 done:
 376         /* Check for route change invalidating send tags. */
 377 #ifdef KERN_TLS
 378         if (tls != NULL) {
 379                 if (error == EAGAIN)
 380                         error = ktls_output_eagain(inp, tls);
 381                 ktls_free(tls);
 382         }
 383 #endif
 384 #ifdef RATELIMIT
 385         if (error == EAGAIN)
 386                 in_pcboutput_eagain(inp);
 387 #endif
 388         return (error);
 389 }
 390
 391 /*
 392  * IP6 output.
 393  * The packet in mbuf chain m contains a skeletal IP6 header (with pri, len,
 394  * nxt, hlim, src, dst).
 395  * This function may modify ver and hlim only.
 396  * The mbuf chain containing the packet will be freed.
 397  * The mbuf opt, if present, will not be freed.
 398  * If route_in6 ro is present and has ro_nh initialized, route lookup would be
 399  * skipped and ro->ro_nh would be used. If ro is present but ro->ro_nh is NULL,
 400  * then result of route lookup is stored in ro->ro_nh.
 401  *
 402  * Type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and nd_ifinfo.linkmtu
 403  * is uint32_t.  So we use u_long to hold largest one, which is rt_mtu.
 404  *
 405  * ifpp - XXX: just for statistics
 406  */
 407 int
 408 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 409     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 410     struct ifnet **ifpp, struct inpcb *inp)
 411 {
 412         struct ip6_hdr *ip6;
 413         struct ifnet *ifp, *origifp;
 414         struct mbuf *m = m0;
 415         struct mbuf *mprev;
 416         struct route_in6 *ro_pmtu;
 417         struct nhop_object *nh;
 418         struct sockaddr_in6 *dst, sin6, src_sa, dst_sa;
 419         struct in6_addr odst;
 420         u_char *nexthdrp;
 421         int tlen, len;
 422         int error = 0;
 423         int vlan_pcp = -1;
 424         struct in6_ifaddr *ia = NULL;
 425         u_long mtu;
 426         int alwaysfrag, dontfrag;
 427         u_int32_t optlen, plen = 0, unfragpartlen;
 428         struct ip6_exthdrs exthdrs;
 429         struct in6_addr src0, dst0;
 430         u_int32_t zone;
 431         bool hdrsplit;
 432         int sw_csum, tso;
 433         int needfiblookup;
 434         uint32_t fibnum;
 435         struct m_tag *fwd_tag = NULL;
 436         uint32_t id;
 437
 438         NET_EPOCH_ASSERT();
 439
 440         if (inp != NULL) {
 441                 INP_LOCK_ASSERT(inp);
 442                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 443                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 444                         /* Unconditionally set flowid. */
 445                         m->m_pkthdr.flowid = inp->inp_flowid;
 446                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 447                 }
 448                 if ((inp->inp_flags2 & INP_2PCP_SET) != 0)
 449                         vlan_pcp = (inp->inp_flags2 & INP_2PCP_MASK) >>
 450                             INP_2PCP_SHIFT;
 451 #ifdef NUMA
 452                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 453 #endif
 454         }
 455
 456 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 457         /*
 458          * IPSec checking which handles several cases.
 459          * FAST IPSEC: We re-injected the packet.
 460          * XXX: need scope argument.
 461          */
 462         if (IPSEC_ENABLED(ipv6)) {
 463                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 464                         if (error == EINPROGRESS)
 465                                 error = 0;
 466                         goto done;
 467                 }
 468         }
 469 #endif /* IPSEC */
 470
 471         /* Source address validation. */
 472         ip6 = mtod(m, struct ip6_hdr *);
 473         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 474             (flags & IPV6_UNSPECSRC) == 0) {
 475                 error = EOPNOTSUPP;
 476                 IP6STAT_INC(ip6s_badscope);
 477                 goto bad;
 478         }
 479         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 480                 error = EOPNOTSUPP;
 481                 IP6STAT_INC(ip6s_badscope);
 482                 goto bad;
 483         }
 484
 485         /*
 486          * If we are given packet options to add extension headers prepare them.
 487          * Calculate the total length of the extension header chain.
 488          * Keep the length of the unfragmentable part for fragmentation.
 489          */
 490         bzero(&exthdrs, sizeof(exthdrs));
 491         optlen = 0;
 492         unfragpartlen = sizeof(struct ip6_hdr);
 493         if (opt) {
 494                 /* Hop-by-Hop options header. */
 495                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh, optlen);
 496
 497                 /* Destination options header (1st part). */
 498                 if (opt->ip6po_rthdr) {
 499 #ifndef RTHDR_SUPPORT_IMPLEMENTED
 500                         /*
 501                          * If there is a routing header, discard the packet
 502                          * right away here. RH0/1 are obsolete and we do not
 503                          * currently support RH2/3/4.
 504                          * People trying to use RH253/254 may want to disable
 505                          * this check.
 506                          * The moment we do support any routing header (again)
 507                          * this block should check the routing type more
 508                          * selectively.
 509                          */
 510                         error = EINVAL;
 511                         goto bad;
 512 #endif
 513
 514                         /*
 515                          * Destination options header (1st part).
 516                          * This only makes sense with a routing header.
 517                          * See Section 9.2 of RFC 3542.
 518                          * Disabling this part just for MIP6 convenience is
 519                          * a bad idea.  We need to think carefully about a
 520                          * way to make the advanced API coexist with MIP6
 521                          * options, which might automatically be inserted in
 522                          * the kernel.
 523                          */
 524                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1,
 525                             optlen);
 526                 }
 527                 /* Routing header. */
 528                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr, optlen);
 529
 530                 unfragpartlen += optlen;
 531
 532                 /*
 533                  * NOTE: we don't add AH/ESP length here (done in
 534                  * ip6_ipsec_output()).
 535                  */
 536
 537                 /* Destination options header (2nd part). */
 538                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2, optlen);
 539         }
 540
 541         /*
 542          * If there is at least one extension header,
 543          * separate IP6 header from the payload.
 544          */
 545         hdrsplit = false;
 546         if (optlen) {
 547                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 548                         m = NULL;
 549                         goto freehdrs;
 550                 }
 551                 m = exthdrs.ip6e_ip6;
 552                 ip6 = mtod(m, struct ip6_hdr *);
 553                 hdrsplit = true;
 554         }
 555
 556         /* Adjust mbuf packet header length. */
 557         m->m_pkthdr.len += optlen;
 558         plen = m->m_pkthdr.len - sizeof(*ip6);
 559
 560         /* If this is a jumbo payload, insert a jumbo payload option. */
 561         if (plen > IPV6_MAXPACKET) {
 562                 if (!hdrsplit) {
 563                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 564                                 m = NULL;
 565                                 goto freehdrs;
 566                         }
 567                         m = exthdrs.ip6e_ip6;
 568                         ip6 = mtod(m, struct ip6_hdr *);
 569                         hdrsplit = true;
 570                 }
 571                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 572                         goto freehdrs;
 573                 ip6->ip6_plen = 0;
 574         } else
 575                 ip6->ip6_plen = htons(plen);
 576         nexthdrp = &ip6->ip6_nxt;
 577
 578         if (optlen) {
 579                 /*
 580                  * Concatenate headers and fill in next header fields.
 581                  * Here we have, on "m"
 582                  *      IPv6 payload
 583                  * and we insert headers accordingly.
 584                  * Finally, we should be getting:
 585                  *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload].
 586                  *
 587                  * During the header composing process "m" points to IPv6
 588                  * header.  "mprev" points to an extension header prior to esp.
 589                  */
 590                 mprev = m;
 591
 592                 /*
 593                  * We treat dest2 specially.  This makes IPsec processing
 594                  * much easier.  The goal here is to make mprev point the
 595                  * mbuf prior to dest2.
 596                  *
 597                  * Result: IPv6 dest2 payload.
 598                  * m and mprev will point to IPv6 header.
 599                  */
 600                 if (exthdrs.ip6e_dest2) {
 601                         if (!hdrsplit)
 602                                 panic("%s:%d: assumption failed: "
 603                                     "hdr not split: hdrsplit %d exthdrs %p",
 604                                     __func__, __LINE__, hdrsplit, &exthdrs);
 605                         exthdrs.ip6e_dest2->m_next = m->m_next;
 606                         m->m_next = exthdrs.ip6e_dest2;
 607                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 608                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 609                 }
 610
 611                 /*
 612                  * Result: IPv6 hbh dest1 rthdr dest2 payload.
 613                  * m will point to IPv6 header.  mprev will point to the
 614                  * extension header prior to dest2 (rthdr in the above case).
 615                  */
 616                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 617                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 618                            IPPROTO_DSTOPTS);
 619                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 620                            IPPROTO_ROUTING);
 621         }
 622
 623         IP6STAT_INC(ip6s_localout);
 624
 625         /* Route packet. */
 626         ro_pmtu = ro;
 627         if (opt && opt->ip6po_rthdr)
 628                 ro = &opt->ip6po_route;
 629         if (ro != NULL)
 630                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 631         else
 632                 dst = &sin6;
 633         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 634
 635 again:
 636         /*
 637          * If specified, try to fill in the traffic class field.
 638          * Do not override if a non-zero value is already set.
 639          * We check the diffserv field and the ECN field separately.
 640          */
 641         if (opt && opt->ip6po_tclass >= 0) {
 642                 int mask = 0;
 643
 644                 if (IPV6_DSCP(ip6) == 0)
 645                         mask |= 0xfc;
 646                 if (IPV6_ECN(ip6) == 0)
 647                         mask |= 0x03;
 648                 if (mask != 0)
 649                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 650         }
 651
 652         /* Fill in or override the hop limit field, if necessary. */
 653         if (opt && opt->ip6po_hlim != -1)
 654                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 655         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 656                 if (im6o != NULL)
 657                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 658                 else
 659                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 660         }
 661
 662         if (ro == NULL || ro->ro_nh == NULL) {
 663                 bzero(dst, sizeof(*dst));
 664                 dst->sin6_family = AF_INET6;
 665                 dst->sin6_len = sizeof(*dst);
 666                 dst->sin6_addr = ip6->ip6_dst;
 667         }
 668         /*
 669          * Validate route against routing table changes.
 670          * Make sure that the address family is set in route.
 671          */
 672         nh = NULL;
 673         ifp = NULL;
 674         mtu = 0;
 675         if (ro != NULL) {
 676                 if (ro->ro_nh != NULL && inp != NULL) {
 677                         ro->ro_dst.sin6_family = AF_INET6; /* XXX KASSERT? */
 678                         NH_VALIDATE((struct route *)ro, &inp->inp_rt_cookie,
 679                             fibnum);
 680                 }
 681                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 682                     (!NH_IS_VALID(ro->ro_nh) ||
 683                     ro->ro_dst.sin6_family != AF_INET6 ||
 684                     !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)))
 685                         RO_INVALIDATE_CACHE(ro);
 686
 687                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 688                     ro->ro_dst.sin6_family == AF_INET6 &&
 689                     IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 690                         /* Nexthop is valid and contains valid ifp */
 691                         nh = ro->ro_nh;
 692                 } else {
 693                         if (ro->ro_lle)
 694                                 LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 695                         ro->ro_lle = NULL;
 696                         if (fwd_tag == NULL) {
 697                                 bzero(&dst_sa, sizeof(dst_sa));
 698                                 dst_sa.sin6_family = AF_INET6;
 699                                 dst_sa.sin6_len = sizeof(dst_sa);
 700                                 dst_sa.sin6_addr = ip6->ip6_dst;
 701                         }
 702                         error = in6_selectroute(&dst_sa, opt, im6o, ro, &ifp,
 703                             &nh, fibnum, m->m_pkthdr.flowid);
 704                         if (error != 0) {
 705                                 IP6STAT_INC(ip6s_noroute);
 706                                 if (ifp != NULL)
 707                                         in6_ifstat_inc(ifp, ifs6_out_discard);
 708                                 goto bad;
 709                         }
 710                         /*
 711                          * At this point at least @ifp is not NULL
 712                          * Can be the case when dst is multicast, link-local or
 713                          * interface is explicitly specificed by the caller.
 714                          */
 715                 }
 716                 if (nh == NULL) {
 717                         /*
 718                          * If in6_selectroute() does not return a nexthop
 719                          * dst may not have been updated.
 720                          */
 721                         *dst = dst_sa;  /* XXX */
 722                         origifp = ifp;
 723                         mtu = ifp->if_mtu;
 724                 } else {
 725                         ifp = nh->nh_ifp;
 726                         origifp = nh->nh_aifp;
 727                         ia = (struct in6_ifaddr *)(nh->nh_ifa);
 728                         counter_u64_add(nh->nh_pksent, 1);
 729                 }
 730         } else {
 731                 struct nhop_object *nh;
 732                 struct in6_addr kdst;
 733                 uint32_t scopeid;
 734
 735                 if (fwd_tag == NULL) {
 736                         bzero(&dst_sa, sizeof(dst_sa));
 737                         dst_sa.sin6_family = AF_INET6;
 738                         dst_sa.sin6_len = sizeof(dst_sa);
 739                         dst_sa.sin6_addr = ip6->ip6_dst;
 740                 }
 741
 742                 if (IN6_IS_ADDR_MULTICAST(&dst_sa.sin6_addr) &&
 743                     im6o != NULL &&
 744                     (ifp = im6o->im6o_multicast_ifp) != NULL) {
 745                         /* We do not need a route lookup. */
 746                         *dst = dst_sa;  /* XXX */
 747                         origifp = ifp;
 748                         goto nonh6lookup;
 749                 }
 750
 751                 in6_splitscope(&dst_sa.sin6_addr, &kdst, &scopeid);
 752
 753                 if (IN6_IS_ADDR_MC_LINKLOCAL(&dst_sa.sin6_addr) ||
 754                     IN6_IS_ADDR_MC_NODELOCAL(&dst_sa.sin6_addr)) {
 755                         if (scopeid > 0) {
 756                                 ifp = in6_getlinkifnet(scopeid);
 757                                 if (ifp == NULL) {
 758                                         error = EHOSTUNREACH;
 759                                         goto bad;
 760                                 }
 761                                 *dst = dst_sa;  /* XXX */
 762                                 origifp = ifp;
 763                                 goto nonh6lookup;
 764                         }
 765                 }
 766
 767                 nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE,
 768                     m->m_pkthdr.flowid);
 769                 if (nh == NULL) {
 770                         IP6STAT_INC(ip6s_noroute);
 771                         /* No ifp in6_ifstat_inc(ifp, ifs6_out_discard); */
 772                         error = EHOSTUNREACH;;
 773                         goto bad;
 774                 }
 775
 776                 ifp = nh->nh_ifp;
 777                 origifp = nh->nh_aifp;
 778                 ia = ifatoia6(nh->nh_ifa);
 779                 if (nh->nh_flags & NHF_GATEWAY)
 780                         dst->sin6_addr = nh->gw6_sa.sin6_addr;
 781                 else if (fwd_tag != NULL)
 782                         dst->sin6_addr = dst_sa.sin6_addr;
 783 nonh6lookup:
 784                 ;
 785         }
 786         /*
 787          * At this point ifp MUST be pointing to the valid transmit ifp.
 788          * origifp MUST be valid and pointing to either the same ifp or,
 789          * in case of loopback output, to the interface which ip6_src
 790          * belongs to.
 791          * Examples:
 792          *  fe80::1%em0 -> fe80::2%em0 -> ifp=em0, origifp=em0
 793          *  fe80::1%em0 -> fe80::1%em0 -> ifp=lo0, origifp=em0
 794          *  ::1 -> ::1 -> ifp=lo0, origifp=lo0
 795          *
 796          * mtu can be 0 and will be refined later.
 797          */
 798         KASSERT((ifp != NULL), ("output interface must not be NULL"));
 799         KASSERT((origifp != NULL), ("output address interface must not be NULL"));
 800
 801         if ((flags & IPV6_FORWARDING) == 0) {
 802                 /* XXX: the FORWARDING flag can be set for mrouting. */
 803                 in6_ifstat_inc(ifp, ifs6_out_request);
 804         }
 805
 806         /* Setup data structures for scope ID checks. */
 807         src0 = ip6->ip6_src;
 808         bzero(&src_sa, sizeof(src_sa));
 809         src_sa.sin6_family = AF_INET6;
 810         src_sa.sin6_len = sizeof(src_sa);
 811         src_sa.sin6_addr = ip6->ip6_src;
 812
 813         dst0 = ip6->ip6_dst;
 814         /* Re-initialize to be sure. */
 815         bzero(&dst_sa, sizeof(dst_sa));
 816         dst_sa.sin6_family = AF_INET6;
 817         dst_sa.sin6_len = sizeof(dst_sa);
 818         dst_sa.sin6_addr = ip6->ip6_dst;
 819
 820         /* Check for valid scope ID. */
 821         if (in6_setscope(&src0, origifp, &zone) == 0 &&
 822             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 823             in6_setscope(&dst0, origifp, &zone) == 0 &&
 824             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 825                 /*
 826                  * The outgoing interface is in the zone of the source
 827                  * and destination addresses.
 828                  *
 829                  */
 830         } else if ((origifp->if_flags & IFF_LOOPBACK) == 0 ||
 831             sa6_recoverscope(&src_sa) != 0 ||
 832             sa6_recoverscope(&dst_sa) != 0 ||
 833             dst_sa.sin6_scope_id == 0 ||
 834             (src_sa.sin6_scope_id != 0 &&
 835             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 836             ifnet_byindex(dst_sa.sin6_scope_id) == NULL) {
 837                 /*
 838                  * If the destination network interface is not a
 839                  * loopback interface, or the destination network
 840                  * address has no scope ID, or the source address has
 841                  * a scope ID set which is different from the
 842                  * destination address one, or there is no network
 843                  * interface representing this scope ID, the address
 844                  * pair is considered invalid.
 845                  */
 846                 IP6STAT_INC(ip6s_badscope);
 847                 in6_ifstat_inc(origifp, ifs6_out_discard);
 848                 if (error == 0)
 849                         error = EHOSTUNREACH; /* XXX */
 850                 goto bad;
 851         }
 852         /* All scope ID checks are successful. */
 853
 854         if (nh && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 855                 if (opt && opt->ip6po_nextroute.ro_nh) {
 856                         /*
 857                          * The nexthop is explicitly specified by the
 858                          * application.  We assume the next hop is an IPv6
 859                          * address.
 860                          */
 861                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 862                 }
 863                 else if ((nh->nh_flags & NHF_GATEWAY))
 864                         dst = &nh->gw6_sa;
 865         }
 866
 867         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 868                 m->m_flags &= ~(M_BCAST | M_MCAST); /* Just in case. */
 869         } else {
 870                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 871                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 872
 873                 /* Confirm that the outgoing interface supports multicast. */
 874                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 875                         IP6STAT_INC(ip6s_noroute);
 876                         in6_ifstat_inc(ifp, ifs6_out_discard);
 877                         error = ENETUNREACH;
 878                         goto bad;
 879                 }
 880                 if ((im6o == NULL && in6_mcast_loop) ||
 881                     (im6o && im6o->im6o_multicast_loop)) {
 882                         /*
 883                          * Loop back multicast datagram if not expressly
 884                          * forbidden to do so, even if we have not joined
 885                          * the address; protocols will filter it later,
 886                          * thus deferring a hash lookup and lock acquisition
 887                          * at the expense of an m_copym().
 888                          */
 889                         ip6_mloopback(ifp, m);
 890                 } else {
 891                         /*
 892                          * If we are acting as a multicast router, perform
 893                          * multicast forwarding as if the packet had just
 894                          * arrived on the interface to which we are about
 895                          * to send.  The multicast forwarding function
 896                          * recursively calls this function, using the
 897                          * IPV6_FORWARDING flag to prevent infinite recursion.
 898                          *
 899                          * Multicasts that are looped back by ip6_mloopback(),
 900                          * above, will be forwarded by the ip6_input() routine,
 901                          * if necessary.
 902                          */
 903                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 904                                 /*
 905                                  * XXX: ip6_mforward expects that rcvif is NULL
 906                                  * when it is called from the originating path.
 907                                  * However, it may not always be the case.
 908                                  */
 909                                 m->m_pkthdr.rcvif = NULL;
 910                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 911                                         m_freem(m);
 912                                         goto done;
 913                                 }
 914                         }
 915                 }
 916                 /*
 917                  * Multicasts with a hoplimit of zero may be looped back,
 918                  * above, but must not be transmitted on a network.
 919                  * Also, multicasts addressed to the loopback interface
 920                  * are not sent -- the above call to ip6_mloopback() will
 921                  * loop back a copy if this host actually belongs to the
 922                  * destination group on the loopback interface.
 923                  */
 924                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 925                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 926                         m_freem(m);
 927                         goto done;
 928                 }
 929         }
 930
 931         /*
 932          * Fill the outgoing inteface to tell the upper layer
 933          * to increment per-interface statistics.
 934          */
 935         if (ifpp)
 936                 *ifpp = ifp;
 937
 938         /* Determine path MTU. */
 939         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 940                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 941                 goto bad;
 942         KASSERT(mtu > 0, ("%s:%d: mtu %ld, ro_pmtu %p ro %p ifp %p "
 943             "alwaysfrag %d fibnum %u\n", __func__, __LINE__, mtu, ro_pmtu, ro,
 944             ifp, alwaysfrag, fibnum));
 945
 946         /*
 947          * The caller of this function may specify to use the minimum MTU
 948          * in some cases.
 949          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 950          * setting.  The logic is a bit complicated; by default, unicast
 951          * packets will follow path MTU while multicast packets will be sent at
 952          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 953          * including unicast ones will be sent at the minimum MTU.  Multicast
 954          * packets will always be sent at the minimum MTU unless
 955          * IP6PO_MINMTU_DISABLE is explicitly specified.
 956          * See RFC 3542 for more details.
 957          */
 958         if (mtu > IPV6_MMTU) {
 959                 if ((flags & IPV6_MINMTU))
 960                         mtu = IPV6_MMTU;
 961                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 962                         mtu = IPV6_MMTU;
 963                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 964                          (opt == NULL ||
 965                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 966                         mtu = IPV6_MMTU;
 967                 }
 968         }
 969
 970         /*
 971          * Clear embedded scope identifiers if necessary.
 972          * in6_clearscope() will touch the addresses only when necessary.
 973          */
 974         in6_clearscope(&ip6->ip6_src);
 975         in6_clearscope(&ip6->ip6_dst);
 976
 977         /*
 978          * If the outgoing packet contains a hop-by-hop options header,
 979          * it must be examined and processed even by the source node.
 980          * (RFC 2460, section 4.)
 981          */
 982         if (exthdrs.ip6e_hbh) {
 983                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 984                 u_int32_t dummy; /* XXX unused */
 985                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 986
 987 #ifdef DIAGNOSTIC
 988                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 989                         panic("ip6e_hbh is not contiguous");
 990 #endif
 991                 /*
 992                  *  XXX: if we have to send an ICMPv6 error to the sender,
 993                  *       we need the M_LOOP flag since icmp6_error() expects
 994                  *       the IPv6 and the hop-by-hop options header are
 995                  *       contiguous unless the flag is set.
 996                  */
 997                 m->m_flags |= M_LOOP;
 998                 m->m_pkthdr.rcvif = ifp;
 999                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
1000                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
1001                     &dummy, &plen) < 0) {
1002                         /* m was already freed at this point. */
1003                         error = EINVAL;/* better error? */
1004                         goto done;
1005                 }
1006                 m->m_flags &= ~M_LOOP; /* XXX */
1007                 m->m_pkthdr.rcvif = NULL;
1008         }
1009
1010         /* Jump over all PFIL processing if hooks are not active. */
1011         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
1012                 goto passout;
1013
1014         odst = ip6->ip6_dst;
1015         /* Run through list of hooks for output packets. */
1016         switch (pfil_mbuf_out(V_inet6_pfil_head, &m, ifp, inp)) {
1017         case PFIL_PASS:
1018                 ip6 = mtod(m, struct ip6_hdr *);
1019                 break;
1020         case PFIL_DROPPED:
1021                 error = EACCES;
1022                 /* FALLTHROUGH */
1023         case PFIL_CONSUMED:
1024                 goto done;
1025         }
1026
1027         needfiblookup = 0;
1028         /* See if destination IP address was changed by packet filter. */
1029         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
1030                 m->m_flags |= M_SKIP_FIREWALL;
1031                 /* If destination is now ourself drop to ip6_input(). */
1032                 if (in6_localip(&ip6->ip6_dst)) {
1033                         m->m_flags |= M_FASTFWD_OURS;
1034                         if (m->m_pkthdr.rcvif == NULL)
1035                                 m->m_pkthdr.rcvif = V_loif;
1036                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1037                                 m->m_pkthdr.csum_flags |=
1038                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1039                                 m->m_pkthdr.csum_data = 0xffff;
1040                         }
1041 #if defined(SCTP) || defined(SCTP_SUPPORT)
1042                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1043                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1044 #endif
1045                         error = netisr_queue(NETISR_IPV6, m);
1046                         goto done;
1047                 } else {
1048                         if (ro != NULL)
1049                                 RO_INVALIDATE_CACHE(ro);
1050                         needfiblookup = 1; /* Redo the routing table lookup. */
1051                 }
1052         }
1053         /* See if fib was changed by packet filter. */
1054         if (fibnum != M_GETFIB(m)) {
1055                 m->m_flags |= M_SKIP_FIREWALL;
1056                 fibnum = M_GETFIB(m);
1057                 if (ro != NULL)
1058                         RO_INVALIDATE_CACHE(ro);
1059                 needfiblookup = 1;
1060         }
1061         if (needfiblookup)
1062                 goto again;
1063
1064         /* See if local, if yes, send it to netisr. */
1065         if (m->m_flags & M_FASTFWD_OURS) {
1066                 if (m->m_pkthdr.rcvif == NULL)
1067                         m->m_pkthdr.rcvif = V_loif;
1068                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1069                         m->m_pkthdr.csum_flags |=
1070                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1071                         m->m_pkthdr.csum_data = 0xffff;
1072                 }
1073 #if defined(SCTP) || defined(SCTP_SUPPORT)
1074                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1075                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1076 #endif
1077                 error = netisr_queue(NETISR_IPV6, m);
1078                 goto done;
1079         }
1080         /* Or forward to some other address? */
1081         if ((m->m_flags & M_IP6_NEXTHOP) &&
1082             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
1083                 if (ro != NULL)
1084                         dst = (struct sockaddr_in6 *)&ro->ro_dst;
1085                 else
1086                         dst = &sin6;
1087                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
1088                 m->m_flags |= M_SKIP_FIREWALL;
1089                 m->m_flags &= ~M_IP6_NEXTHOP;
1090                 m_tag_delete(m, fwd_tag);
1091                 goto again;
1092         }
1093
1094 passout:
1095         if (vlan_pcp > -1)
1096                 EVL_APPLY_PRI(m, vlan_pcp);
1097
1098         /* Ensure the packet data is mapped if the interface requires it. */
1099         if ((ifp->if_capenable & IFCAP_MEXTPG) == 0) {
1100                 m = mb_unmapped_to_ext(m);
1101                 if (m == NULL) {
1102                         IP6STAT_INC(ip6s_odropped);
1103                         return (ENOBUFS);
1104                 }
1105         }
1106
1107         /*
1108          * Send the packet to the outgoing interface.
1109          * If necessary, do IPv6 fragmentation before sending.
1110          *
1111          * The logic here is rather complex:
1112          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
1113          * 1-a: send as is if tlen <= path mtu
1114          * 1-b: fragment if tlen > path mtu
1115          *
1116          * 2: if user asks us not to fragment (dontfrag == 1)
1117          * 2-a: send as is if tlen <= interface mtu
1118          * 2-b: error if tlen > interface mtu
1119          *
1120          * 3: if we always need to attach fragment header (alwaysfrag == 1)
1121          *      always fragment
1122          *
1123          * 4: if dontfrag == 1 && alwaysfrag == 1
1124          *      error, as we cannot handle this conflicting request.
1125          */
1126         sw_csum = m->m_pkthdr.csum_flags;
1127         if (!hdrsplit) {
1128                 tso = ((sw_csum & ifp->if_hwassist &
1129                     (CSUM_TSO | CSUM_INNER_TSO)) != 0) ? 1 : 0;
1130                 sw_csum &= ~ifp->if_hwassist;
1131         } else
1132                 tso = 0;
1133         /*
1134          * If we added extension headers, we will not do TSO and calculate the
1135          * checksums ourselves for now.
1136          * XXX-BZ  Need a framework to know when the NIC can handle it, even
1137          * with ext. hdrs.
1138          */
1139         ip6_output_delayed_csum(m, ifp, sw_csum, plen, optlen);
1140         /* XXX-BZ m->m_pkthdr.csum_flags &= ~ifp->if_hwassist; */
1141         tlen = m->m_pkthdr.len;
1142
1143         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1144                 dontfrag = 1;
1145         else
1146                 dontfrag = 0;
1147         if (dontfrag && alwaysfrag) {   /* Case 4. */
1148                 /* Conflicting request - can't transmit. */
1149                 error = EMSGSIZE;
1150                 goto bad;
1151         }
1152         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* Case 2-b. */
1153                 /*
1154                  * Even if the DONTFRAG option is specified, we cannot send the
1155                  * packet when the data length is larger than the MTU of the
1156                  * outgoing interface.
1157                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1158                  * application wanted to know the MTU value. Also return an
1159                  * error code (this is not described in the API spec).
1160                  */
1161                 if (inp != NULL)
1162                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1163                 error = EMSGSIZE;
1164                 goto bad;
1165         }
1166
1167         /* Transmit packet without fragmentation. */
1168         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* Cases 1-a and 2-a. */
1169                 struct in6_ifaddr *ia6;
1170
1171                 ip6 = mtod(m, struct ip6_hdr *);
1172                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1173                 if (ia6) {
1174                         /* Record statistics for this interface address. */
1175                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1176                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1177                             m->m_pkthdr.len);
1178                 }
1179                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1180                     (flags & IP_NO_SND_TAG_RL) ? false : true);
1181                 goto done;
1182         }
1183
1184         /* Try to fragment the packet.  Cases 1-b and 3. */
1185         if (mtu < IPV6_MMTU) {
1186                 /* Path MTU cannot be less than IPV6_MMTU. */
1187                 error = EMSGSIZE;
1188                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1189                 goto bad;
1190         } else if (ip6->ip6_plen == 0) {
1191                 /* Jumbo payload cannot be fragmented. */
1192                 error = EMSGSIZE;
1193                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1194                 goto bad;
1195         } else {
1196                 u_char nextproto;
1197
1198                 /*
1199                  * Too large for the destination or interface;
1200                  * fragment if possible.
1201                  * Must be able to put at least 8 bytes per fragment.
1202                  */
1203                 if (mtu > IPV6_MAXPACKET)
1204                         mtu = IPV6_MAXPACKET;
1205
1206                 len = (mtu - unfragpartlen - sizeof(struct ip6_frag)) & ~7;
1207                 if (len < 8) {
1208                         error = EMSGSIZE;
1209                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1210                         goto bad;
1211                 }
1212
1213                 /*
1214                  * If the interface will not calculate checksums on
1215                  * fragmented packets, then do it here.
1216                  * XXX-BZ handle the hw offloading case.  Need flags.
1217                  */
1218                 ip6_output_delayed_csum(m, ifp, m->m_pkthdr.csum_flags, plen,
1219                     optlen);
1220
1221                 /*
1222                  * Change the next header field of the last header in the
1223                  * unfragmentable part.
1224                  */
1225                 if (exthdrs.ip6e_rthdr) {
1226                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1227                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1228                 } else if (exthdrs.ip6e_dest1) {
1229                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1230                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1231                 } else if (exthdrs.ip6e_hbh) {
1232                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1233                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1234                 } else {
1235                         ip6 = mtod(m, struct ip6_hdr *);
1236                         nextproto = ip6->ip6_nxt;
1237                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1238                 }
1239
1240                 /*
1241                  * Loop through length of segment after first fragment,
1242                  * make new header and copy data of each part and link onto
1243                  * chain.
1244                  */
1245                 m0 = m;
1246                 id = htonl(ip6_randomid());
1247                 error = ip6_fragment(ifp, m, unfragpartlen, nextproto,len, id);
1248                 if (error != 0)
1249                         goto sendorfree;
1250
1251                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1252         }
1253
1254         /* Remove leading garbage. */
1255 sendorfree:
1256         m = m0->m_nextpkt;
1257         m0->m_nextpkt = 0;
1258         m_freem(m0);
1259         for (; m; m = m0) {
1260                 m0 = m->m_nextpkt;
1261                 m->m_nextpkt = 0;
1262                 if (error == 0) {
1263                         /* Record statistics for this interface address. */
1264                         if (ia) {
1265                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1266                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1267                                     m->m_pkthdr.len);
1268                         }
1269                         if (vlan_pcp > -1)
1270                                 EVL_APPLY_PRI(m, vlan_pcp);
1271                         error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1272                             true);
1273                 } else
1274                         m_freem(m);
1275         }
1276
1277         if (error == 0)
1278                 IP6STAT_INC(ip6s_fragmented);
1279
1280 done:
1281         return (error);
1282
1283 freehdrs:
1284         m_freem(exthdrs.ip6e_hbh);      /* m_freem() checks if mbuf is NULL. */
1285         m_freem(exthdrs.ip6e_dest1);
1286         m_freem(exthdrs.ip6e_rthdr);
1287         m_freem(exthdrs.ip6e_dest2);
1288         /* FALLTHROUGH */
1289 bad:
1290         if (m)
1291                 m_freem(m);
1292         goto done;
1293 }
1294
1295 static int
1296 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1297 {
1298         struct mbuf *m;
1299
1300         if (hlen > MCLBYTES)
1301                 return (ENOBUFS); /* XXX */
1302
1303         if (hlen > MLEN)
1304                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1305         else
1306                 m = m_get(M_NOWAIT, MT_DATA);
1307         if (m == NULL)
1308                 return (ENOBUFS);
1309         m->m_len = hlen;
1310         if (hdr)
1311                 bcopy(hdr, mtod(m, caddr_t), hlen);
1312
1313         *mp = m;
1314         return (0);
1315 }
1316
1317 /*
1318  * Insert jumbo payload option.
1319  */
1320 static int
1321 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1322 {
1323         struct mbuf *mopt;
1324         u_char *optbuf;
1325         u_int32_t v;
1326
1327 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1328
1329         /*
1330          * If there is no hop-by-hop options header, allocate new one.
1331          * If there is one but it doesn't have enough space to store the
1332          * jumbo payload option, allocate a cluster to store the whole options.
1333          * Otherwise, use it to store the options.
1334          */
1335         if (exthdrs->ip6e_hbh == NULL) {
1336                 mopt = m_get(M_NOWAIT, MT_DATA);
1337                 if (mopt == NULL)
1338                         return (ENOBUFS);
1339                 mopt->m_len = JUMBOOPTLEN;
1340                 optbuf = mtod(mopt, u_char *);
1341                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1342                 exthdrs->ip6e_hbh = mopt;
1343         } else {
1344                 struct ip6_hbh *hbh;
1345
1346                 mopt = exthdrs->ip6e_hbh;
1347                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1348                         /*
1349                          * XXX assumption:
1350                          * - exthdrs->ip6e_hbh is not referenced from places
1351                          *   other than exthdrs.
1352                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1353                          */
1354                         int oldoptlen = mopt->m_len;
1355                         struct mbuf *n;
1356
1357                         /*
1358                          * XXX: give up if the whole (new) hbh header does
1359                          * not fit even in an mbuf cluster.
1360                          */
1361                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1362                                 return (ENOBUFS);
1363
1364                         /*
1365                          * As a consequence, we must always prepare a cluster
1366                          * at this point.
1367                          */
1368                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1369                         if (n == NULL)
1370                                 return (ENOBUFS);
1371                         n->m_len = oldoptlen + JUMBOOPTLEN;
1372                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1373                             oldoptlen);
1374                         optbuf = mtod(n, caddr_t) + oldoptlen;
1375                         m_freem(mopt);
1376                         mopt = exthdrs->ip6e_hbh = n;
1377                 } else {
1378                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1379                         mopt->m_len += JUMBOOPTLEN;
1380                 }
1381                 optbuf[0] = IP6OPT_PADN;
1382                 optbuf[1] = 1;
1383
1384                 /*
1385                  * Adjust the header length according to the pad and
1386                  * the jumbo payload option.
1387                  */
1388                 hbh = mtod(mopt, struct ip6_hbh *);
1389                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1390         }
1391
1392         /* fill in the option. */
1393         optbuf[2] = IP6OPT_JUMBO;
1394         optbuf[3] = 4;
1395         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1396         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1397
1398         /* finally, adjust the packet header length */
1399         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1400
1401         return (0);
1402 #undef JUMBOOPTLEN
1403 }
1404
1405 /*
1406  * Insert fragment header and copy unfragmentable header portions.
1407  */
1408 static int
1409 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1410     struct ip6_frag **frghdrp)
1411 {
1412         struct mbuf *n, *mlast;
1413
1414         if (hlen > sizeof(struct ip6_hdr)) {
1415                 n = m_copym(m0, sizeof(struct ip6_hdr),
1416                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1417                 if (n == NULL)
1418                         return (ENOBUFS);
1419                 m->m_next = n;
1420         } else
1421                 n = m;
1422
1423         /* Search for the last mbuf of unfragmentable part. */
1424         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1425                 ;
1426
1427         if (M_WRITABLE(mlast) &&
1428             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1429                 /* use the trailing space of the last mbuf for the fragment hdr */
1430                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1431                     mlast->m_len);
1432                 mlast->m_len += sizeof(struct ip6_frag);
1433                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1434         } else {
1435                 /* allocate a new mbuf for the fragment header */
1436                 struct mbuf *mfrg;
1437
1438                 mfrg = m_get(M_NOWAIT, MT_DATA);
1439                 if (mfrg == NULL)
1440                         return (ENOBUFS);
1441                 mfrg->m_len = sizeof(struct ip6_frag);
1442                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1443                 mlast->m_next = mfrg;
1444         }
1445
1446         return (0);
1447 }
1448
1449 /*
1450  * Calculates IPv6 path mtu for destination @dst.
1451  * Resulting MTU is stored in @mtup.
1452  *
1453  * Returns 0 on success.
1454  */
1455 static int
1456 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1457 {
1458         struct epoch_tracker et;
1459         struct nhop_object *nh;
1460         struct in6_addr kdst;
1461         uint32_t scopeid;
1462         int error;
1463
1464         in6_splitscope(dst, &kdst, &scopeid);
1465
1466         NET_EPOCH_ENTER(et);
1467         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1468         if (nh != NULL)
1469                 error = ip6_calcmtu(nh->nh_ifp, dst, nh->nh_mtu, mtup, NULL, 0);
1470         else
1471                 error = EHOSTUNREACH;
1472         NET_EPOCH_EXIT(et);
1473
1474         return (error);
1475 }
1476
1477 /*
1478  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1479  * and cached data in @ro_pmtu.
1480  * MTU from (successful) route lookup is saved (along with dst)
1481  * inside @ro_pmtu to avoid subsequent route lookups after packet
1482  * filter processing.
1483  *
1484  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1485  * Returns 0 on success.
1486  */
1487 static int
1488 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1489     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1490     int *alwaysfragp, u_int fibnum, u_int proto)
1491 {
1492         struct nhop_object *nh;
1493         struct in6_addr kdst;
1494         uint32_t scopeid;
1495         struct sockaddr_in6 *sa6_dst, sin6;
1496         u_long mtu;
1497
1498         NET_EPOCH_ASSERT();
1499
1500         mtu = 0;
1501         if (ro_pmtu == NULL || do_lookup) {
1502                 /*
1503                  * Here ro_pmtu has final destination address, while
1504                  * ro might represent immediate destination.
1505                  * Use ro_pmtu destination since mtu might differ.
1506                  */
1507                 if (ro_pmtu != NULL) {
1508                         sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1509                         if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1510                                 ro_pmtu->ro_mtu = 0;
1511                 } else
1512                         sa6_dst = &sin6;
1513
1514                 if (ro_pmtu == NULL || ro_pmtu->ro_mtu == 0) {
1515                         bzero(sa6_dst, sizeof(*sa6_dst));
1516                         sa6_dst->sin6_family = AF_INET6;
1517                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1518                         sa6_dst->sin6_addr = *dst;
1519
1520                         in6_splitscope(dst, &kdst, &scopeid);
1521                         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1522                         if (nh != NULL) {
1523                                 mtu = nh->nh_mtu;
1524                                 if (ro_pmtu != NULL)
1525                                         ro_pmtu->ro_mtu = mtu;
1526                         }
1527                 } else
1528                         mtu = ro_pmtu->ro_mtu;
1529         }
1530
1531         if (ro_pmtu != NULL && ro_pmtu->ro_nh != NULL)
1532                 mtu = ro_pmtu->ro_nh->nh_mtu;
1533
1534         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1535 }
1536
1537 /*
1538  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1539  * hostcache data for @dst.
1540  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1541  *
1542  * Returns 0 on success.
1543  */
1544 static int
1545 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1546     u_long *mtup, int *alwaysfragp, u_int proto)
1547 {
1548         u_long mtu = 0;
1549         int alwaysfrag = 0;
1550         int error = 0;
1551
1552         if (rt_mtu > 0) {
1553                 u_int32_t ifmtu;
1554                 struct in_conninfo inc;
1555
1556                 bzero(&inc, sizeof(inc));
1557                 inc.inc_flags |= INC_ISIPV6;
1558                 inc.inc6_faddr = *dst;
1559
1560                 ifmtu = IN6_LINKMTU(ifp);
1561
1562                 /* TCP is known to react to pmtu changes so skip hc */
1563                 if (proto != IPPROTO_TCP)
1564                         mtu = tcp_hc_getmtu(&inc);
1565
1566                 if (mtu)
1567                         mtu = min(mtu, rt_mtu);
1568                 else
1569                         mtu = rt_mtu;
1570                 if (mtu == 0)
1571                         mtu = ifmtu;
1572                 else if (mtu < IPV6_MMTU) {
1573                         /*
1574                          * RFC2460 section 5, last paragraph:
1575                          * if we record ICMPv6 too big message with
1576                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1577                          * or smaller, with framgent header attached.
1578                          * (fragment header is needed regardless from the
1579                          * packet size, for translators to identify packets)
1580                          */
1581                         alwaysfrag = 1;
1582                         mtu = IPV6_MMTU;
1583                 }
1584         } else if (ifp) {
1585                 mtu = IN6_LINKMTU(ifp);
1586         } else
1587                 error = EHOSTUNREACH; /* XXX */
1588
1589         *mtup = mtu;
1590         if (alwaysfragp)
1591                 *alwaysfragp = alwaysfrag;
1592         return (error);
1593 }
1594
1595 /*
1596  * IP6 socket option processing.
1597  */
1598 int
1599 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1600 {
1601         int optdatalen, uproto;
1602         void *optdata;
1603         struct inpcb *inp = sotoinpcb(so);
1604         int error, optval;
1605         int level, op, optname;
1606         int optlen;
1607         struct thread *td;
1608 #ifdef  RSS
1609         uint32_t rss_bucket;
1610         int retval;
1611 #endif
1612
1613 /*
1614  * Don't use more than a quarter of mbuf clusters.  N.B.:
1615  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1616  * on LP64 architectures, so cast to u_long to avoid undefined
1617  * behavior.  ILP32 architectures cannot have nmbclusters
1618  * large enough to overflow for other reasons.
1619  */
1620 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1621
1622         level = sopt->sopt_level;
1623         op = sopt->sopt_dir;
1624         optname = sopt->sopt_name;
1625         optlen = sopt->sopt_valsize;
1626         td = sopt->sopt_td;
1627         error = 0;
1628         optval = 0;
1629         uproto = (int)so->so_proto->pr_protocol;
1630
1631         if (level != IPPROTO_IPV6) {
1632                 error = EINVAL;
1633
1634                 if (sopt->sopt_level == SOL_SOCKET &&
1635                     sopt->sopt_dir == SOPT_SET) {
1636                         switch (sopt->sopt_name) {
1637                         case SO_REUSEADDR:
1638                                 INP_WLOCK(inp);
1639                                 if ((so->so_options & SO_REUSEADDR) != 0)
1640                                         inp->inp_flags2 |= INP_REUSEADDR;
1641                                 else
1642                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1643                                 INP_WUNLOCK(inp);
1644                                 error = 0;
1645                                 break;
1646                         case SO_REUSEPORT:
1647                                 INP_WLOCK(inp);
1648                                 if ((so->so_options & SO_REUSEPORT) != 0)
1649                                         inp->inp_flags2 |= INP_REUSEPORT;
1650                                 else
1651                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1652                                 INP_WUNLOCK(inp);
1653                                 error = 0;
1654                                 break;
1655                         case SO_REUSEPORT_LB:
1656                                 INP_WLOCK(inp);
1657                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1658                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1659                                 else
1660                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1661                                 INP_WUNLOCK(inp);
1662                                 error = 0;
1663                                 break;
1664                         case SO_SETFIB:
1665                                 INP_WLOCK(inp);
1666                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1667                                 INP_WUNLOCK(inp);
1668                                 error = 0;
1669                                 break;
1670                         case SO_MAX_PACING_RATE:
1671 #ifdef RATELIMIT
1672                                 INP_WLOCK(inp);
1673                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1674                                 INP_WUNLOCK(inp);
1675                                 error = 0;
1676 #else
1677                                 error = EOPNOTSUPP;
1678 #endif
1679                                 break;
1680                         default:
1681                                 break;
1682                         }
1683                 }
1684         } else {                /* level == IPPROTO_IPV6 */
1685                 switch (op) {
1686                 case SOPT_SET:
1687                         switch (optname) {
1688                         case IPV6_2292PKTOPTIONS:
1689 #ifdef IPV6_PKTOPTIONS
1690                         case IPV6_PKTOPTIONS:
1691 #endif
1692                         {
1693                                 struct mbuf *m;
1694
1695                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1696                                         printf("ip6_ctloutput: mbuf limit hit\n");
1697                                         error = ENOBUFS;
1698                                         break;
1699                                 }
1700
1701                                 error = soopt_getm(sopt, &m); /* XXX */
1702                                 if (error != 0)
1703                                         break;
1704                                 error = soopt_mcopyin(sopt, m); /* XXX */
1705                                 if (error != 0)
1706                                         break;
1707                                 INP_WLOCK(inp);
1708                                 error = ip6_pcbopts(&inp->in6p_outputopts, m,
1709                                     so, sopt);
1710                                 INP_WUNLOCK(inp);
1711                                 m_freem(m); /* XXX */
1712                                 break;
1713                         }
1714
1715                         /*
1716                          * Use of some Hop-by-Hop options or some
1717                          * Destination options, might require special
1718                          * privilege.  That is, normal applications
1719                          * (without special privilege) might be forbidden
1720                          * from setting certain options in outgoing packets,
1721                          * and might never see certain options in received
1722                          * packets. [RFC 2292 Section 6]
1723                          * KAME specific note:
1724                          *  KAME prevents non-privileged users from sending or
1725                          *  receiving ANY hbh/dst options in order to avoid
1726                          *  overhead of parsing options in the kernel.
1727                          */
1728                         case IPV6_RECVHOPOPTS:
1729                         case IPV6_RECVDSTOPTS:
1730                         case IPV6_RECVRTHDRDSTOPTS:
1731                                 if (td != NULL) {
1732                                         error = priv_check(td,
1733                                             PRIV_NETINET_SETHDROPTS);
1734                                         if (error)
1735                                                 break;
1736                                 }
1737                                 /* FALLTHROUGH */
1738                         case IPV6_UNICAST_HOPS:
1739                         case IPV6_HOPLIMIT:
1740
1741                         case IPV6_RECVPKTINFO:
1742                         case IPV6_RECVHOPLIMIT:
1743                         case IPV6_RECVRTHDR:
1744                         case IPV6_RECVPATHMTU:
1745                         case IPV6_RECVTCLASS:
1746                         case IPV6_RECVFLOWID:
1747 #ifdef  RSS
1748                         case IPV6_RECVRSSBUCKETID:
1749 #endif
1750                         case IPV6_V6ONLY:
1751                         case IPV6_AUTOFLOWLABEL:
1752                         case IPV6_ORIGDSTADDR:
1753                         case IPV6_BINDANY:
1754                         case IPV6_BINDMULTI:
1755 #ifdef  RSS
1756                         case IPV6_RSS_LISTEN_BUCKET:
1757 #endif
1758                         case IPV6_VLAN_PCP:
1759                                 if (optname == IPV6_BINDANY && td != NULL) {
1760                                         error = priv_check(td,
1761                                             PRIV_NETINET_BINDANY);
1762                                         if (error)
1763                                                 break;
1764                                 }
1765
1766                                 if (optlen != sizeof(int)) {
1767                                         error = EINVAL;
1768                                         break;
1769                                 }
1770                                 error = sooptcopyin(sopt, &optval,
1771                                         sizeof optval, sizeof optval);
1772                                 if (error)
1773                                         break;
1774                                 switch (optname) {
1775                                 case IPV6_UNICAST_HOPS:
1776                                         if (optval < -1 || optval >= 256)
1777                                                 error = EINVAL;
1778                                         else {
1779                                                 /* -1 = kernel default */
1780                                                 inp->in6p_hops = optval;
1781                                                 if ((inp->inp_vflag &
1782                                                      INP_IPV4) != 0)
1783                                                         inp->inp_ip_ttl = optval;
1784                                         }
1785                                         break;
1786 #define OPTSET(bit) \
1787 do { \
1788         INP_WLOCK(inp); \
1789         if (optval) \
1790                 inp->inp_flags |= (bit); \
1791         else \
1792                 inp->inp_flags &= ~(bit); \
1793         INP_WUNLOCK(inp); \
1794 } while (/*CONSTCOND*/ 0)
1795 #define OPTSET2292(bit) \
1796 do { \
1797         INP_WLOCK(inp); \
1798         inp->inp_flags |= IN6P_RFC2292; \
1799         if (optval) \
1800                 inp->inp_flags |= (bit); \
1801         else \
1802                 inp->inp_flags &= ~(bit); \
1803         INP_WUNLOCK(inp); \
1804 } while (/*CONSTCOND*/ 0)
1805 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1806
1807 #define OPTSET2_N(bit, val) do {                                        \
1808         if (val)                                                        \
1809                 inp->inp_flags2 |= bit;                                 \
1810         else                                                            \
1811                 inp->inp_flags2 &= ~bit;                                \
1812 } while (0)
1813 #define OPTSET2(bit, val) do {                                          \
1814         INP_WLOCK(inp);                                                 \
1815         OPTSET2_N(bit, val);                                            \
1816         INP_WUNLOCK(inp);                                               \
1817 } while (0)
1818 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1819 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1820 do {                                                                    \
1821         INP_WLOCK(inp);                                                 \
1822         if (OPTBIT(IN6P_RFC2292)) {                                     \
1823                 error = EINVAL;                                         \
1824         } else {                                                        \
1825                 if (optval)                                             \
1826                         inp->inp_flags |= (bit);                        \
1827                 else                                                    \
1828                         inp->inp_flags &= ~(bit);                       \
1829         }                                                               \
1830         INP_WUNLOCK(inp);                                               \
1831 } while (/*CONSTCOND*/ 0)
1832
1833                                 case IPV6_RECVPKTINFO:
1834                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1835                                         break;
1836
1837                                 case IPV6_HOPLIMIT:
1838                                 {
1839                                         struct ip6_pktopts **optp;
1840
1841                                         /* cannot mix with RFC2292 */
1842                                         if (OPTBIT(IN6P_RFC2292)) {
1843                                                 error = EINVAL;
1844                                                 break;
1845                                         }
1846                                         INP_WLOCK(inp);
1847                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1848                                                 INP_WUNLOCK(inp);
1849                                                 return (ECONNRESET);
1850                                         }
1851                                         optp = &inp->in6p_outputopts;
1852                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1853                                             (u_char *)&optval, sizeof(optval),
1854                                             optp, (td != NULL) ? td->td_ucred :
1855                                             NULL, uproto);
1856                                         INP_WUNLOCK(inp);
1857                                         break;
1858                                 }
1859
1860                                 case IPV6_RECVHOPLIMIT:
1861                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1862                                         break;
1863
1864                                 case IPV6_RECVHOPOPTS:
1865                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1866                                         break;
1867
1868                                 case IPV6_RECVDSTOPTS:
1869                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1870                                         break;
1871
1872                                 case IPV6_RECVRTHDRDSTOPTS:
1873                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1874                                         break;
1875
1876                                 case IPV6_RECVRTHDR:
1877                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1878                                         break;
1879
1880                                 case IPV6_RECVPATHMTU:
1881                                         /*
1882                                          * We ignore this option for TCP
1883                                          * sockets.
1884                                          * (RFC3542 leaves this case
1885                                          * unspecified.)
1886                                          */
1887                                         if (uproto != IPPROTO_TCP)
1888                                                 OPTSET(IN6P_MTU);
1889                                         break;
1890
1891                                 case IPV6_RECVFLOWID:
1892                                         OPTSET2(INP_RECVFLOWID, optval);
1893                                         break;
1894
1895 #ifdef  RSS
1896                                 case IPV6_RECVRSSBUCKETID:
1897                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1898                                         break;
1899 #endif
1900
1901                                 case IPV6_V6ONLY:
1902                                         INP_WLOCK(inp);
1903                                         if (inp->inp_lport ||
1904                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1905                                                 /*
1906                                                  * The socket is already bound.
1907                                                  */
1908                                                 INP_WUNLOCK(inp);
1909                                                 error = EINVAL;
1910                                                 break;
1911                                         }
1912                                         if (optval) {
1913                                                 inp->inp_flags |= IN6P_IPV6_V6ONLY;
1914                                                 inp->inp_vflag &= ~INP_IPV4;
1915                                         } else {
1916                                                 inp->inp_flags &= ~IN6P_IPV6_V6ONLY;
1917                                                 inp->inp_vflag |= INP_IPV4;
1918                                         }
1919                                         INP_WUNLOCK(inp);
1920                                         break;
1921                                 case IPV6_RECVTCLASS:
1922                                         /* cannot mix with RFC2292 XXX */
1923                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1924                                         break;
1925                                 case IPV6_AUTOFLOWLABEL:
1926                                         OPTSET(IN6P_AUTOFLOWLABEL);
1927                                         break;
1928
1929                                 case IPV6_ORIGDSTADDR:
1930                                         OPTSET2(INP_ORIGDSTADDR, optval);
1931                                         break;
1932                                 case IPV6_BINDANY:
1933                                         OPTSET(INP_BINDANY);
1934                                         break;
1935
1936                                 case IPV6_BINDMULTI:
1937                                         OPTSET2(INP_BINDMULTI, optval);
1938                                         break;
1939 #ifdef  RSS
1940                                 case IPV6_RSS_LISTEN_BUCKET:
1941                                         if ((optval >= 0) &&
1942                                             (optval < rss_getnumbuckets())) {
1943                                                 INP_WLOCK(inp);
1944                                                 inp->inp_rss_listen_bucket = optval;
1945                                                 OPTSET2_N(INP_RSS_BUCKET_SET, 1);
1946                                                 INP_WUNLOCK(inp);
1947                                         } else {
1948                                                 error = EINVAL;
1949                                         }
1950                                         break;
1951 #endif
1952                                 case IPV6_VLAN_PCP:
1953                                         if ((optval >= -1) && (optval <=
1954                                             (INP_2PCP_MASK >> INP_2PCP_SHIFT))) {
1955                                                 if (optval == -1) {
1956                                                         INP_WLOCK(inp);
1957                                                         inp->inp_flags2 &=
1958                                                             ~(INP_2PCP_SET |
1959                                                             INP_2PCP_MASK);
1960                                                         INP_WUNLOCK(inp);
1961                                                 } else {
1962                                                         INP_WLOCK(inp);
1963                                                         inp->inp_flags2 |=
1964                                                             INP_2PCP_SET;
1965                                                         inp->inp_flags2 &=
1966                                                             ~INP_2PCP_MASK;
1967                                                         inp->inp_flags2 |=
1968                                                             optval <<
1969                                                             INP_2PCP_SHIFT;
1970                                                         INP_WUNLOCK(inp);
1971                                                 }
1972                                         } else
1973                                                 error = EINVAL;
1974                                         break;
1975                                 }
1976                                 break;
1977
1978                         case IPV6_TCLASS:
1979                         case IPV6_DONTFRAG:
1980                         case IPV6_USE_MIN_MTU:
1981                         case IPV6_PREFER_TEMPADDR:
1982                                 if (optlen != sizeof(optval)) {
1983                                         error = EINVAL;
1984                                         break;
1985                                 }
1986                                 error = sooptcopyin(sopt, &optval,
1987                                         sizeof optval, sizeof optval);
1988                                 if (error)
1989                                         break;
1990                                 {
1991                                         struct ip6_pktopts **optp;
1992                                         INP_WLOCK(inp);
1993                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1994                                                 INP_WUNLOCK(inp);
1995                                                 return (ECONNRESET);
1996                                         }
1997                                         optp = &inp->in6p_outputopts;
1998                                         error = ip6_pcbopt(optname,
1999                                             (u_char *)&optval, sizeof(optval),
2000                                             optp, (td != NULL) ? td->td_ucred :
2001                                             NULL, uproto);
2002                                         INP_WUNLOCK(inp);
2003                                         break;
2004                                 }
2005
2006                         case IPV6_2292PKTINFO:
2007                         case IPV6_2292HOPLIMIT:
2008                         case IPV6_2292HOPOPTS:
2009                         case IPV6_2292DSTOPTS:
2010                         case IPV6_2292RTHDR:
2011                                 /* RFC 2292 */
2012                                 if (optlen != sizeof(int)) {
2013                                         error = EINVAL;
2014                                         break;
2015                                 }
2016                                 error = sooptcopyin(sopt, &optval,
2017                                         sizeof optval, sizeof optval);
2018                                 if (error)
2019                                         break;
2020                                 switch (optname) {
2021                                 case IPV6_2292PKTINFO:
2022                                         OPTSET2292(IN6P_PKTINFO);
2023                                         break;
2024                                 case IPV6_2292HOPLIMIT:
2025                                         OPTSET2292(IN6P_HOPLIMIT);
2026                                         break;
2027                                 case IPV6_2292HOPOPTS:
2028                                         /*
2029                                          * Check super-user privilege.
2030                                          * See comments for IPV6_RECVHOPOPTS.
2031                                          */
2032                                         if (td != NULL) {
2033                                                 error = priv_check(td,
2034                                                     PRIV_NETINET_SETHDROPTS);
2035                                                 if (error)
2036                                                         return (error);
2037                                         }
2038                                         OPTSET2292(IN6P_HOPOPTS);
2039                                         break;
2040                                 case IPV6_2292DSTOPTS:
2041                                         if (td != NULL) {
2042                                                 error = priv_check(td,
2043                                                     PRIV_NETINET_SETHDROPTS);
2044                                                 if (error)
2045                                                         return (error);
2046                                         }
2047                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
2048                                         break;
2049                                 case IPV6_2292RTHDR:
2050                                         OPTSET2292(IN6P_RTHDR);
2051                                         break;
2052                                 }
2053                                 break;
2054                         case IPV6_PKTINFO:
2055                         case IPV6_HOPOPTS:
2056                         case IPV6_RTHDR:
2057                         case IPV6_DSTOPTS:
2058                         case IPV6_RTHDRDSTOPTS:
2059                         case IPV6_NEXTHOP:
2060                         {
2061                                 /* new advanced API (RFC3542) */
2062                                 u_char *optbuf;
2063                                 u_char optbuf_storage[MCLBYTES];
2064                                 int optlen;
2065                                 struct ip6_pktopts **optp;
2066
2067                                 /* cannot mix with RFC2292 */
2068                                 if (OPTBIT(IN6P_RFC2292)) {
2069                                         error = EINVAL;
2070                                         break;
2071                                 }
2072
2073                                 /*
2074                                  * We only ensure valsize is not too large
2075                                  * here.  Further validation will be done
2076                                  * later.
2077                                  */
2078                                 error = sooptcopyin(sopt, optbuf_storage,
2079                                     sizeof(optbuf_storage), 0);
2080                                 if (error)
2081                                         break;
2082                                 optlen = sopt->sopt_valsize;
2083                                 optbuf = optbuf_storage;
2084                                 INP_WLOCK(inp);
2085                                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
2086                                         INP_WUNLOCK(inp);
2087                                         return (ECONNRESET);
2088                                 }
2089                                 optp = &inp->in6p_outputopts;
2090                                 error = ip6_pcbopt(optname, optbuf, optlen,
2091                                     optp, (td != NULL) ? td->td_ucred : NULL,
2092                                     uproto);
2093                                 INP_WUNLOCK(inp);
2094                                 break;
2095                         }
2096 #undef OPTSET
2097
2098                         case IPV6_MULTICAST_IF:
2099                         case IPV6_MULTICAST_HOPS:
2100                         case IPV6_MULTICAST_LOOP:
2101                         case IPV6_JOIN_GROUP:
2102                         case IPV6_LEAVE_GROUP:
2103                         case IPV6_MSFILTER:
2104                         case MCAST_BLOCK_SOURCE:
2105                         case MCAST_UNBLOCK_SOURCE:
2106                         case MCAST_JOIN_GROUP:
2107                         case MCAST_LEAVE_GROUP:
2108                         case MCAST_JOIN_SOURCE_GROUP:
2109                         case MCAST_LEAVE_SOURCE_GROUP:
2110                                 error = ip6_setmoptions(inp, sopt);
2111                                 break;
2112
2113                         case IPV6_PORTRANGE:
2114                                 error = sooptcopyin(sopt, &optval,
2115                                     sizeof optval, sizeof optval);
2116                                 if (error)
2117                                         break;
2118
2119                                 INP_WLOCK(inp);
2120                                 switch (optval) {
2121                                 case IPV6_PORTRANGE_DEFAULT:
2122                                         inp->inp_flags &= ~(INP_LOWPORT);
2123                                         inp->inp_flags &= ~(INP_HIGHPORT);
2124                                         break;
2125
2126                                 case IPV6_PORTRANGE_HIGH:
2127                                         inp->inp_flags &= ~(INP_LOWPORT);
2128                                         inp->inp_flags |= INP_HIGHPORT;
2129                                         break;
2130
2131                                 case IPV6_PORTRANGE_LOW:
2132                                         inp->inp_flags &= ~(INP_HIGHPORT);
2133                                         inp->inp_flags |= INP_LOWPORT;
2134                                         break;
2135
2136                                 default:
2137                                         error = EINVAL;
2138                                         break;
2139                                 }
2140                                 INP_WUNLOCK(inp);
2141                                 break;
2142
2143 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2144                         case IPV6_IPSEC_POLICY:
2145                                 if (IPSEC_ENABLED(ipv6)) {
2146                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2147                                         break;
2148                                 }
2149                                 /* FALLTHROUGH */
2150 #endif /* IPSEC */
2151
2152                         default:
2153                                 error = ENOPROTOOPT;
2154                                 break;
2155                         }
2156                         break;
2157
2158                 case SOPT_GET:
2159                         switch (optname) {
2160                         case IPV6_2292PKTOPTIONS:
2161 #ifdef IPV6_PKTOPTIONS
2162                         case IPV6_PKTOPTIONS:
2163 #endif
2164                                 /*
2165                                  * RFC3542 (effectively) deprecated the
2166                                  * semantics of the 2292-style pktoptions.
2167                                  * Since it was not reliable in nature (i.e.,
2168                                  * applications had to expect the lack of some
2169                                  * information after all), it would make sense
2170                                  * to simplify this part by always returning
2171                                  * empty data.
2172                                  */
2173                                 sopt->sopt_valsize = 0;
2174                                 break;
2175
2176                         case IPV6_RECVHOPOPTS:
2177                         case IPV6_RECVDSTOPTS:
2178                         case IPV6_RECVRTHDRDSTOPTS:
2179                         case IPV6_UNICAST_HOPS:
2180                         case IPV6_RECVPKTINFO:
2181                         case IPV6_RECVHOPLIMIT:
2182                         case IPV6_RECVRTHDR:
2183                         case IPV6_RECVPATHMTU:
2184
2185                         case IPV6_V6ONLY:
2186                         case IPV6_PORTRANGE:
2187                         case IPV6_RECVTCLASS:
2188                         case IPV6_AUTOFLOWLABEL:
2189                         case IPV6_BINDANY:
2190                         case IPV6_FLOWID:
2191                         case IPV6_FLOWTYPE:
2192                         case IPV6_RECVFLOWID:
2193 #ifdef  RSS
2194                         case IPV6_RSSBUCKETID:
2195                         case IPV6_RECVRSSBUCKETID:
2196 #endif
2197                         case IPV6_BINDMULTI:
2198                         case IPV6_VLAN_PCP:
2199                                 switch (optname) {
2200                                 case IPV6_RECVHOPOPTS:
2201                                         optval = OPTBIT(IN6P_HOPOPTS);
2202                                         break;
2203
2204                                 case IPV6_RECVDSTOPTS:
2205                                         optval = OPTBIT(IN6P_DSTOPTS);
2206                                         break;
2207
2208                                 case IPV6_RECVRTHDRDSTOPTS:
2209                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2210                                         break;
2211
2212                                 case IPV6_UNICAST_HOPS:
2213                                         optval = inp->in6p_hops;
2214                                         break;
2215
2216                                 case IPV6_RECVPKTINFO:
2217                                         optval = OPTBIT(IN6P_PKTINFO);
2218                                         break;
2219
2220                                 case IPV6_RECVHOPLIMIT:
2221                                         optval = OPTBIT(IN6P_HOPLIMIT);
2222                                         break;
2223
2224                                 case IPV6_RECVRTHDR:
2225                                         optval = OPTBIT(IN6P_RTHDR);
2226                                         break;
2227
2228                                 case IPV6_RECVPATHMTU:
2229                                         optval = OPTBIT(IN6P_MTU);
2230                                         break;
2231
2232                                 case IPV6_V6ONLY:
2233                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2234                                         break;
2235
2236                                 case IPV6_PORTRANGE:
2237                                     {
2238                                         int flags;
2239                                         flags = inp->inp_flags;
2240                                         if (flags & INP_HIGHPORT)
2241                                                 optval = IPV6_PORTRANGE_HIGH;
2242                                         else if (flags & INP_LOWPORT)
2243                                                 optval = IPV6_PORTRANGE_LOW;
2244                                         else
2245                                                 optval = 0;
2246                                         break;
2247                                     }
2248                                 case IPV6_RECVTCLASS:
2249                                         optval = OPTBIT(IN6P_TCLASS);
2250                                         break;
2251
2252                                 case IPV6_AUTOFLOWLABEL:
2253                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2254                                         break;
2255
2256                                 case IPV6_ORIGDSTADDR:
2257                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2258                                         break;
2259
2260                                 case IPV6_BINDANY:
2261                                         optval = OPTBIT(INP_BINDANY);
2262                                         break;
2263
2264                                 case IPV6_FLOWID:
2265                                         optval = inp->inp_flowid;
2266                                         break;
2267
2268                                 case IPV6_FLOWTYPE:
2269                                         optval = inp->inp_flowtype;
2270                                         break;
2271
2272                                 case IPV6_RECVFLOWID:
2273                                         optval = OPTBIT2(INP_RECVFLOWID);
2274                                         break;
2275 #ifdef  RSS
2276                                 case IPV6_RSSBUCKETID:
2277                                         retval =
2278                                             rss_hash2bucket(inp->inp_flowid,
2279                                             inp->inp_flowtype,
2280                                             &rss_bucket);
2281                                         if (retval == 0)
2282                                                 optval = rss_bucket;
2283                                         else
2284                                                 error = EINVAL;
2285                                         break;
2286
2287                                 case IPV6_RECVRSSBUCKETID:
2288                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2289                                         break;
2290 #endif
2291
2292                                 case IPV6_BINDMULTI:
2293                                         optval = OPTBIT2(INP_BINDMULTI);
2294                                         break;
2295
2296                                 case IPV6_VLAN_PCP:
2297                                         if (OPTBIT2(INP_2PCP_SET)) {
2298                                                 optval = (inp->inp_flags2 &
2299                                                             INP_2PCP_MASK) >>
2300                                                             INP_2PCP_SHIFT;
2301                                         } else {
2302                                                 optval = -1;
2303                                         }
2304                                         break;
2305                                 }
2306
2307                                 if (error)
2308                                         break;
2309                                 error = sooptcopyout(sopt, &optval,
2310                                         sizeof optval);
2311                                 break;
2312
2313                         case IPV6_PATHMTU:
2314                         {
2315                                 u_long pmtu = 0;
2316                                 struct ip6_mtuinfo mtuinfo;
2317                                 struct in6_addr addr;
2318
2319                                 if (!(so->so_state & SS_ISCONNECTED))
2320                                         return (ENOTCONN);
2321                                 /*
2322                                  * XXX: we dot not consider the case of source
2323                                  * routing, or optional information to specify
2324                                  * the outgoing interface.
2325                                  * Copy faddr out of inp to avoid holding lock
2326                                  * on inp during route lookup.
2327                                  */
2328                                 INP_RLOCK(inp);
2329                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2330                                 INP_RUNLOCK(inp);
2331                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2332                                     &addr, &pmtu);
2333                                 if (error)
2334                                         break;
2335                                 if (pmtu > IPV6_MAXPACKET)
2336                                         pmtu = IPV6_MAXPACKET;
2337
2338                                 bzero(&mtuinfo, sizeof(mtuinfo));
2339                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2340                                 optdata = (void *)&mtuinfo;
2341                                 optdatalen = sizeof(mtuinfo);
2342                                 error = sooptcopyout(sopt, optdata,
2343                                     optdatalen);
2344                                 break;
2345                         }
2346
2347                         case IPV6_2292PKTINFO:
2348                         case IPV6_2292HOPLIMIT:
2349                         case IPV6_2292HOPOPTS:
2350                         case IPV6_2292RTHDR:
2351                         case IPV6_2292DSTOPTS:
2352                                 switch (optname) {
2353                                 case IPV6_2292PKTINFO:
2354                                         optval = OPTBIT(IN6P_PKTINFO);
2355                                         break;
2356                                 case IPV6_2292HOPLIMIT:
2357                                         optval = OPTBIT(IN6P_HOPLIMIT);
2358                                         break;
2359                                 case IPV6_2292HOPOPTS:
2360                                         optval = OPTBIT(IN6P_HOPOPTS);
2361                                         break;
2362                                 case IPV6_2292RTHDR:
2363                                         optval = OPTBIT(IN6P_RTHDR);
2364                                         break;
2365                                 case IPV6_2292DSTOPTS:
2366                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2367                                         break;
2368                                 }
2369                                 error = sooptcopyout(sopt, &optval,
2370                                     sizeof optval);
2371                                 break;
2372                         case IPV6_PKTINFO:
2373                         case IPV6_HOPOPTS:
2374                         case IPV6_RTHDR:
2375                         case IPV6_DSTOPTS:
2376                         case IPV6_RTHDRDSTOPTS:
2377                         case IPV6_NEXTHOP:
2378                         case IPV6_TCLASS:
2379                         case IPV6_DONTFRAG:
2380                         case IPV6_USE_MIN_MTU:
2381                         case IPV6_PREFER_TEMPADDR:
2382                                 error = ip6_getpcbopt(inp, optname, sopt);
2383                                 break;
2384
2385                         case IPV6_MULTICAST_IF:
2386                         case IPV6_MULTICAST_HOPS:
2387                         case IPV6_MULTICAST_LOOP:
2388                         case IPV6_MSFILTER:
2389                                 error = ip6_getmoptions(inp, sopt);
2390                                 break;
2391
2392 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2393                         case IPV6_IPSEC_POLICY:
2394                                 if (IPSEC_ENABLED(ipv6)) {
2395                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2396                                         break;
2397                                 }
2398                                 /* FALLTHROUGH */
2399 #endif /* IPSEC */
2400                         default:
2401                                 error = ENOPROTOOPT;
2402                                 break;
2403                         }
2404                         break;
2405                 }
2406         }
2407         return (error);
2408 }
2409
2410 int
2411 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2412 {
2413         int error = 0, optval, optlen;
2414         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2415         struct inpcb *inp = sotoinpcb(so);
2416         int level, op, optname;
2417
2418         level = sopt->sopt_level;
2419         op = sopt->sopt_dir;
2420         optname = sopt->sopt_name;
2421         optlen = sopt->sopt_valsize;
2422
2423         if (level != IPPROTO_IPV6) {
2424                 return (EINVAL);
2425         }
2426
2427         switch (optname) {
2428         case IPV6_CHECKSUM:
2429                 /*
2430                  * For ICMPv6 sockets, no modification allowed for checksum
2431                  * offset, permit "no change" values to help existing apps.
2432                  *
2433                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2434                  * for an ICMPv6 socket will fail."
2435                  * The current behavior does not meet RFC3542.
2436                  */
2437                 switch (op) {
2438                 case SOPT_SET:
2439                         if (optlen != sizeof(int)) {
2440                                 error = EINVAL;
2441                                 break;
2442                         }
2443                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2444                                             sizeof(optval));
2445                         if (error)
2446                                 break;
2447                         if (optval < -1 || (optval % 2) != 0) {
2448                                 /*
2449                                  * The API assumes non-negative even offset
2450                                  * values or -1 as a special value.
2451                                  */
2452                                 error = EINVAL;
2453                         } else if (inp->inp_ip_p == IPPROTO_ICMPV6) {
2454                                 if (optval != icmp6off)
2455                                         error = EINVAL;
2456                         } else
2457                                 inp->in6p_cksum = optval;
2458                         break;
2459
2460                 case SOPT_GET:
2461                         if (inp->inp_ip_p == IPPROTO_ICMPV6)
2462                                 optval = icmp6off;
2463                         else
2464                                 optval = inp->in6p_cksum;
2465
2466                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2467                         break;
2468
2469                 default:
2470                         error = EINVAL;
2471                         break;
2472                 }
2473                 break;
2474
2475         default:
2476                 error = ENOPROTOOPT;
2477                 break;
2478         }
2479
2480         return (error);
2481 }
2482
2483 /*
2484  * Set up IP6 options in pcb for insertion in output packets or
2485  * specifying behavior of outgoing packets.
2486  */
2487 static int
2488 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2489     struct socket *so, struct sockopt *sopt)
2490 {
2491         struct ip6_pktopts *opt = *pktopt;
2492         int error = 0;
2493         struct thread *td = sopt->sopt_td;
2494         struct epoch_tracker et;
2495
2496         /* turn off any old options. */
2497         if (opt) {
2498 #ifdef DIAGNOSTIC
2499                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2500                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2501                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2502                         printf("ip6_pcbopts: all specified options are cleared.\n");
2503 #endif
2504                 ip6_clearpktopts(opt, -1);
2505         } else {
2506                 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT);
2507                 if (opt == NULL)
2508                         return (ENOMEM);
2509         }
2510         *pktopt = NULL;
2511
2512         if (!m || m->m_len == 0) {
2513                 /*
2514                  * Only turning off any previous options, regardless of
2515                  * whether the opt is just created or given.
2516                  */
2517                 free(opt, M_IP6OPT);
2518                 return (0);
2519         }
2520
2521         /*  set options specified by user. */
2522         NET_EPOCH_ENTER(et);
2523         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2524             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2525                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2526                 free(opt, M_IP6OPT);
2527                 NET_EPOCH_EXIT(et);
2528                 return (error);
2529         }
2530         NET_EPOCH_EXIT(et);
2531         *pktopt = opt;
2532         return (0);
2533 }
2534
2535 /*
2536  * initialize ip6_pktopts.  beware that there are non-zero default values in
2537  * the struct.
2538  */
2539 void
2540 ip6_initpktopts(struct ip6_pktopts *opt)
2541 {
2542
2543         bzero(opt, sizeof(*opt));
2544         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2545         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2546         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2547         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2548 }
2549
2550 static int
2551 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2552     struct ucred *cred, int uproto)
2553 {
2554         struct epoch_tracker et;
2555         struct ip6_pktopts *opt;
2556         int ret;
2557
2558         if (*pktopt == NULL) {
2559                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2560                     M_NOWAIT);
2561                 if (*pktopt == NULL)
2562                         return (ENOBUFS);
2563                 ip6_initpktopts(*pktopt);
2564         }
2565         opt = *pktopt;
2566
2567         NET_EPOCH_ENTER(et);
2568         ret = ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto);
2569         NET_EPOCH_EXIT(et);
2570
2571         return (ret);
2572 }
2573
2574 #define GET_PKTOPT_VAR(field, lenexpr) do {                                     \
2575         if (pktopt && pktopt->field) {                                          \
2576                 INP_RUNLOCK(inp);                                               \
2577                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK);         \
2578                 malloc_optdata = true;                                          \
2579                 INP_RLOCK(inp);                                                 \
2580                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {            \
2581                         INP_RUNLOCK(inp);                                       \
2582                         free(optdata, M_TEMP);                                  \
2583                         return (ECONNRESET);                                    \
2584                 }                                                               \
2585                 pktopt = inp->in6p_outputopts;                                  \
2586                 if (pktopt && pktopt->field) {                                  \
2587                         optdatalen = min(lenexpr, sopt->sopt_valsize);          \
2588                         bcopy(pktopt->field, optdata, optdatalen);              \
2589                 } else {                                                        \
2590                         free(optdata, M_TEMP);                                  \
2591                         optdata = NULL;                                         \
2592                         malloc_optdata = false;                                 \
2593                 }                                                               \
2594         }                                                                       \
2595 } while(0)
2596
2597 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                         \
2598         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2599
2600 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                        \
2601         pktopt->field->sa_len)
2602
2603 static int
2604 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2605 {
2606         void *optdata = NULL;
2607         bool malloc_optdata = false;
2608         int optdatalen = 0;
2609         int error = 0;
2610         struct in6_pktinfo null_pktinfo;
2611         int deftclass = 0, on;
2612         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2613         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2614         struct ip6_pktopts *pktopt;
2615
2616         INP_RLOCK(inp);
2617         pktopt = inp->in6p_outputopts;
2618
2619         switch (optname) {
2620         case IPV6_PKTINFO:
2621                 optdata = (void *)&null_pktinfo;
2622                 if (pktopt && pktopt->ip6po_pktinfo) {
2623                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2624                             sizeof(null_pktinfo));
2625                         in6_clearscope(&null_pktinfo.ipi6_addr);
2626                 } else {
2627                         /* XXX: we don't have to do this every time... */
2628                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2629                 }
2630                 optdatalen = sizeof(struct in6_pktinfo);
2631                 break;
2632         case IPV6_TCLASS:
2633                 if (pktopt && pktopt->ip6po_tclass >= 0)
2634                         deftclass = pktopt->ip6po_tclass;
2635                 optdata = (void *)&deftclass;
2636                 optdatalen = sizeof(int);
2637                 break;
2638         case IPV6_HOPOPTS:
2639                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2640                 break;
2641         case IPV6_RTHDR:
2642                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2643                 break;
2644         case IPV6_RTHDRDSTOPTS:
2645                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2646                 break;
2647         case IPV6_DSTOPTS:
2648                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2649                 break;
2650         case IPV6_NEXTHOP:
2651                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2652                 break;
2653         case IPV6_USE_MIN_MTU:
2654                 if (pktopt)
2655                         defminmtu = pktopt->ip6po_minmtu;
2656                 optdata = (void *)&defminmtu;
2657                 optdatalen = sizeof(int);
2658                 break;
2659         case IPV6_DONTFRAG:
2660                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2661                         on = 1;
2662                 else
2663                         on = 0;
2664                 optdata = (void *)&on;
2665                 optdatalen = sizeof(on);
2666                 break;
2667         case IPV6_PREFER_TEMPADDR:
2668                 if (pktopt)
2669                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2670                 optdata = (void *)&defpreftemp;
2671                 optdatalen = sizeof(int);
2672                 break;
2673         default:                /* should not happen */
2674 #ifdef DIAGNOSTIC
2675                 panic("ip6_getpcbopt: unexpected option\n");
2676 #endif
2677                 INP_RUNLOCK(inp);
2678                 return (ENOPROTOOPT);
2679         }
2680         INP_RUNLOCK(inp);
2681
2682         error = sooptcopyout(sopt, optdata, optdatalen);
2683         if (malloc_optdata)
2684                 free(optdata, M_TEMP);
2685
2686         return (error);
2687 }
2688
2689 void
2690 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2691 {
2692         if (pktopt == NULL)
2693                 return;
2694
2695         if (optname == -1 || optname == IPV6_PKTINFO) {
2696                 if (pktopt->ip6po_pktinfo)
2697                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2698                 pktopt->ip6po_pktinfo = NULL;
2699         }
2700         if (optname == -1 || optname == IPV6_HOPLIMIT)
2701                 pktopt->ip6po_hlim = -1;
2702         if (optname == -1 || optname == IPV6_TCLASS)
2703                 pktopt->ip6po_tclass = -1;
2704         if (optname == -1 || optname == IPV6_NEXTHOP) {
2705                 if (pktopt->ip6po_nextroute.ro_nh) {
2706                         NH_FREE(pktopt->ip6po_nextroute.ro_nh);
2707                         pktopt->ip6po_nextroute.ro_nh = NULL;
2708                 }
2709                 if (pktopt->ip6po_nexthop)
2710                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2711                 pktopt->ip6po_nexthop = NULL;
2712         }
2713         if (optname == -1 || optname == IPV6_HOPOPTS) {
2714                 if (pktopt->ip6po_hbh)
2715                         free(pktopt->ip6po_hbh, M_IP6OPT);
2716                 pktopt->ip6po_hbh = NULL;
2717         }
2718         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2719                 if (pktopt->ip6po_dest1)
2720                         free(pktopt->ip6po_dest1, M_IP6OPT);
2721                 pktopt->ip6po_dest1 = NULL;
2722         }
2723         if (optname == -1 || optname == IPV6_RTHDR) {
2724                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2725                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2726                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2727                 if (pktopt->ip6po_route.ro_nh) {
2728                         NH_FREE(pktopt->ip6po_route.ro_nh);
2729                         pktopt->ip6po_route.ro_nh = NULL;
2730                 }
2731         }
2732         if (optname == -1 || optname == IPV6_DSTOPTS) {
2733                 if (pktopt->ip6po_dest2)
2734                         free(pktopt->ip6po_dest2, M_IP6OPT);
2735                 pktopt->ip6po_dest2 = NULL;
2736         }
2737 }
2738
2739 #define PKTOPT_EXTHDRCPY(type) \
2740 do {\
2741         if (src->type) {\
2742                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2743                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2744                 if (dst->type == NULL)\
2745                         goto bad;\
2746                 bcopy(src->type, dst->type, hlen);\
2747         }\
2748 } while (/*CONSTCOND*/ 0)
2749
2750 static int
2751 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2752 {
2753         if (dst == NULL || src == NULL)  {
2754                 printf("ip6_clearpktopts: invalid argument\n");
2755                 return (EINVAL);
2756         }
2757
2758         dst->ip6po_hlim = src->ip6po_hlim;
2759         dst->ip6po_tclass = src->ip6po_tclass;
2760         dst->ip6po_flags = src->ip6po_flags;
2761         dst->ip6po_minmtu = src->ip6po_minmtu;
2762         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2763         if (src->ip6po_pktinfo) {
2764                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2765                     M_IP6OPT, canwait);
2766                 if (dst->ip6po_pktinfo == NULL)
2767                         goto bad;
2768                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2769         }
2770         if (src->ip6po_nexthop) {
2771                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2772                     M_IP6OPT, canwait);
2773                 if (dst->ip6po_nexthop == NULL)
2774                         goto bad;
2775                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2776                     src->ip6po_nexthop->sa_len);
2777         }
2778         PKTOPT_EXTHDRCPY(ip6po_hbh);
2779         PKTOPT_EXTHDRCPY(ip6po_dest1);
2780         PKTOPT_EXTHDRCPY(ip6po_dest2);
2781         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2782         return (0);
2783
2784   bad:
2785         ip6_clearpktopts(dst, -1);
2786         return (ENOBUFS);
2787 }
2788 #undef PKTOPT_EXTHDRCPY
2789
2790 struct ip6_pktopts *
2791 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2792 {
2793         int error;
2794         struct ip6_pktopts *dst;
2795
2796         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2797         if (dst == NULL)
2798                 return (NULL);
2799         ip6_initpktopts(dst);
2800
2801         if ((error = copypktopts(dst, src, canwait)) != 0) {
2802                 free(dst, M_IP6OPT);
2803                 return (NULL);
2804         }
2805
2806         return (dst);
2807 }
2808
2809 void
2810 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2811 {
2812         if (pktopt == NULL)
2813                 return;
2814
2815         ip6_clearpktopts(pktopt, -1);
2816
2817         free(pktopt, M_IP6OPT);
2818 }
2819
2820 /*
2821  * Set IPv6 outgoing packet options based on advanced API.
2822  */
2823 int
2824 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2825     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2826 {
2827         struct cmsghdr *cm = NULL;
2828
2829         if (control == NULL || opt == NULL)
2830                 return (EINVAL);
2831
2832         /*
2833          * ip6_setpktopt can call ifnet_byindex(), so it's imperative that we
2834          * are in the network epoch here.
2835          */
2836         NET_EPOCH_ASSERT();
2837
2838         ip6_initpktopts(opt);
2839         if (stickyopt) {
2840                 int error;
2841
2842                 /*
2843                  * If stickyopt is provided, make a local copy of the options
2844                  * for this particular packet, then override them by ancillary
2845                  * objects.
2846                  * XXX: copypktopts() does not copy the cached route to a next
2847                  * hop (if any).  This is not very good in terms of efficiency,
2848                  * but we can allow this since this option should be rarely
2849                  * used.
2850                  */
2851                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2852                         return (error);
2853         }
2854
2855         /*
2856          * XXX: Currently, we assume all the optional information is stored
2857          * in a single mbuf.
2858          */
2859         if (control->m_next)
2860                 return (EINVAL);
2861
2862         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2863             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2864                 int error;
2865
2866                 if (control->m_len < CMSG_LEN(0))
2867                         return (EINVAL);
2868
2869                 cm = mtod(control, struct cmsghdr *);
2870                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2871                         return (EINVAL);
2872                 if (cm->cmsg_level != IPPROTO_IPV6)
2873                         continue;
2874
2875                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2876                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2877                 if (error)
2878                         return (error);
2879         }
2880
2881         return (0);
2882 }
2883
2884 /*
2885  * Set a particular packet option, as a sticky option or an ancillary data
2886  * item.  "len" can be 0 only when it's a sticky option.
2887  * We have 4 cases of combination of "sticky" and "cmsg":
2888  * "sticky=0, cmsg=0": impossible
2889  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2890  * "sticky=1, cmsg=0": RFC3542 socket option
2891  * "sticky=1, cmsg=1": RFC2292 socket option
2892  */
2893 static int
2894 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2895     struct ucred *cred, int sticky, int cmsg, int uproto)
2896 {
2897         int minmtupolicy, preftemp;
2898         int error;
2899
2900         NET_EPOCH_ASSERT();
2901
2902         if (!sticky && !cmsg) {
2903 #ifdef DIAGNOSTIC
2904                 printf("ip6_setpktopt: impossible case\n");
2905 #endif
2906                 return (EINVAL);
2907         }
2908
2909         /*
2910          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2911          * not be specified in the context of RFC3542.  Conversely,
2912          * RFC3542 types should not be specified in the context of RFC2292.
2913          */
2914         if (!cmsg) {
2915                 switch (optname) {
2916                 case IPV6_2292PKTINFO:
2917                 case IPV6_2292HOPLIMIT:
2918                 case IPV6_2292NEXTHOP:
2919                 case IPV6_2292HOPOPTS:
2920                 case IPV6_2292DSTOPTS:
2921                 case IPV6_2292RTHDR:
2922                 case IPV6_2292PKTOPTIONS:
2923                         return (ENOPROTOOPT);
2924                 }
2925         }
2926         if (sticky && cmsg) {
2927                 switch (optname) {
2928                 case IPV6_PKTINFO:
2929                 case IPV6_HOPLIMIT:
2930                 case IPV6_NEXTHOP:
2931                 case IPV6_HOPOPTS:
2932                 case IPV6_DSTOPTS:
2933                 case IPV6_RTHDRDSTOPTS:
2934                 case IPV6_RTHDR:
2935                 case IPV6_USE_MIN_MTU:
2936                 case IPV6_DONTFRAG:
2937                 case IPV6_TCLASS:
2938                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2939                         return (ENOPROTOOPT);
2940                 }
2941         }
2942
2943         switch (optname) {
2944         case IPV6_2292PKTINFO:
2945         case IPV6_PKTINFO:
2946         {
2947                 struct ifnet *ifp = NULL;
2948                 struct in6_pktinfo *pktinfo;
2949
2950                 if (len != sizeof(struct in6_pktinfo))
2951                         return (EINVAL);
2952
2953                 pktinfo = (struct in6_pktinfo *)buf;
2954
2955                 /*
2956                  * An application can clear any sticky IPV6_PKTINFO option by
2957                  * doing a "regular" setsockopt with ipi6_addr being
2958                  * in6addr_any and ipi6_ifindex being zero.
2959                  * [RFC 3542, Section 6]
2960                  */
2961                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2962                     pktinfo->ipi6_ifindex == 0 &&
2963                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2964                         ip6_clearpktopts(opt, optname);
2965                         break;
2966                 }
2967
2968                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2969                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2970                         return (EINVAL);
2971                 }
2972                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2973                         return (EINVAL);
2974                 /* validate the interface index if specified. */
2975                 if (pktinfo->ipi6_ifindex) {
2976                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2977                         if (ifp == NULL)
2978                                 return (ENXIO);
2979                 }
2980                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2981                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2982                         return (ENETDOWN);
2983
2984                 if (ifp != NULL &&
2985                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2986                         struct in6_ifaddr *ia;
2987
2988                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2989                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2990                         if (ia == NULL)
2991                                 return (EADDRNOTAVAIL);
2992                         ifa_free(&ia->ia_ifa);
2993                 }
2994                 /*
2995                  * We store the address anyway, and let in6_selectsrc()
2996                  * validate the specified address.  This is because ipi6_addr
2997                  * may not have enough information about its scope zone, and
2998                  * we may need additional information (such as outgoing
2999                  * interface or the scope zone of a destination address) to
3000                  * disambiguate the scope.
3001                  * XXX: the delay of the validation may confuse the
3002                  * application when it is used as a sticky option.
3003                  */
3004                 if (opt->ip6po_pktinfo == NULL) {
3005                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
3006                             M_IP6OPT, M_NOWAIT);
3007                         if (opt->ip6po_pktinfo == NULL)
3008                                 return (ENOBUFS);
3009                 }
3010                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
3011                 break;
3012         }
3013
3014         case IPV6_2292HOPLIMIT:
3015         case IPV6_HOPLIMIT:
3016         {
3017                 int *hlimp;
3018
3019                 /*
3020                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
3021                  * to simplify the ordering among hoplimit options.
3022                  */
3023                 if (optname == IPV6_HOPLIMIT && sticky)
3024                         return (ENOPROTOOPT);
3025
3026                 if (len != sizeof(int))
3027                         return (EINVAL);
3028                 hlimp = (int *)buf;
3029                 if (*hlimp < -1 || *hlimp > 255)
3030                         return (EINVAL);
3031
3032                 opt->ip6po_hlim = *hlimp;
3033                 break;
3034         }
3035
3036         case IPV6_TCLASS:
3037         {
3038                 int tclass;
3039
3040                 if (len != sizeof(int))
3041                         return (EINVAL);
3042                 tclass = *(int *)buf;
3043                 if (tclass < -1 || tclass > 255)
3044                         return (EINVAL);
3045
3046                 opt->ip6po_tclass = tclass;
3047                 break;
3048         }
3049
3050         case IPV6_2292NEXTHOP:
3051         case IPV6_NEXTHOP:
3052                 if (cred != NULL) {
3053                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3054                         if (error)
3055                                 return (error);
3056                 }
3057
3058                 if (len == 0) { /* just remove the option */
3059                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
3060                         break;
3061                 }
3062
3063                 /* check if cmsg_len is large enough for sa_len */
3064                 if (len < sizeof(struct sockaddr) || len < *buf)
3065                         return (EINVAL);
3066
3067                 switch (((struct sockaddr *)buf)->sa_family) {
3068                 case AF_INET6:
3069                 {
3070                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
3071                         int error;
3072
3073                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
3074                                 return (EINVAL);
3075
3076                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
3077                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
3078                                 return (EINVAL);
3079                         }
3080                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
3081                             != 0) {
3082                                 return (error);
3083                         }
3084                         break;
3085                 }
3086                 case AF_LINK:   /* should eventually be supported */
3087                 default:
3088                         return (EAFNOSUPPORT);
3089                 }
3090
3091                 /* turn off the previous option, then set the new option. */
3092                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
3093                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
3094                 if (opt->ip6po_nexthop == NULL)
3095                         return (ENOBUFS);
3096                 bcopy(buf, opt->ip6po_nexthop, *buf);
3097                 break;
3098
3099         case IPV6_2292HOPOPTS:
3100         case IPV6_HOPOPTS:
3101         {
3102                 struct ip6_hbh *hbh;
3103                 int hbhlen;
3104
3105                 /*
3106                  * XXX: We don't allow a non-privileged user to set ANY HbH
3107                  * options, since per-option restriction has too much
3108                  * overhead.
3109                  */
3110                 if (cred != NULL) {
3111                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3112                         if (error)
3113                                 return (error);
3114                 }
3115
3116                 if (len == 0) {
3117                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
3118                         break;  /* just remove the option */
3119                 }
3120
3121                 /* message length validation */
3122                 if (len < sizeof(struct ip6_hbh))
3123                         return (EINVAL);
3124                 hbh = (struct ip6_hbh *)buf;
3125                 hbhlen = (hbh->ip6h_len + 1) << 3;
3126                 if (len != hbhlen)
3127                         return (EINVAL);
3128
3129                 /* turn off the previous option, then set the new option. */
3130                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
3131                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
3132                 if (opt->ip6po_hbh == NULL)
3133                         return (ENOBUFS);
3134                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
3135
3136                 break;
3137         }
3138
3139         case IPV6_2292DSTOPTS:
3140         case IPV6_DSTOPTS:
3141         case IPV6_RTHDRDSTOPTS:
3142         {
3143                 struct ip6_dest *dest, **newdest = NULL;
3144                 int destlen;
3145
3146                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
3147                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3148                         if (error)
3149                                 return (error);
3150                 }
3151
3152                 if (len == 0) {
3153                         ip6_clearpktopts(opt, optname);
3154                         break;  /* just remove the option */
3155                 }
3156
3157                 /* message length validation */
3158                 if (len < sizeof(struct ip6_dest))
3159                         return (EINVAL);
3160                 dest = (struct ip6_dest *)buf;
3161                 destlen = (dest->ip6d_len + 1) << 3;
3162                 if (len != destlen)
3163                         return (EINVAL);
3164
3165                 /*
3166                  * Determine the position that the destination options header
3167                  * should be inserted; before or after the routing header.
3168                  */
3169                 switch (optname) {
3170                 case IPV6_2292DSTOPTS:
3171                         /*
3172                          * The old advacned API is ambiguous on this point.
3173                          * Our approach is to determine the position based
3174                          * according to the existence of a routing header.
3175                          * Note, however, that this depends on the order of the
3176                          * extension headers in the ancillary data; the 1st
3177                          * part of the destination options header must appear
3178                          * before the routing header in the ancillary data,
3179                          * too.
3180                          * RFC3542 solved the ambiguity by introducing
3181                          * separate ancillary data or option types.
3182                          */
3183                         if (opt->ip6po_rthdr == NULL)
3184                                 newdest = &opt->ip6po_dest1;
3185                         else
3186                                 newdest = &opt->ip6po_dest2;
3187                         break;
3188                 case IPV6_RTHDRDSTOPTS:
3189                         newdest = &opt->ip6po_dest1;
3190                         break;
3191                 case IPV6_DSTOPTS:
3192                         newdest = &opt->ip6po_dest2;
3193                         break;
3194                 }
3195
3196                 /* turn off the previous option, then set the new option. */
3197                 ip6_clearpktopts(opt, optname);
3198                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3199                 if (*newdest == NULL)
3200                         return (ENOBUFS);
3201                 bcopy(dest, *newdest, destlen);
3202
3203                 break;
3204         }
3205
3206         case IPV6_2292RTHDR:
3207         case IPV6_RTHDR:
3208         {
3209                 struct ip6_rthdr *rth;
3210                 int rthlen;
3211
3212                 if (len == 0) {
3213                         ip6_clearpktopts(opt, IPV6_RTHDR);
3214                         break;  /* just remove the option */
3215                 }
3216
3217                 /* message length validation */
3218                 if (len < sizeof(struct ip6_rthdr))
3219                         return (EINVAL);
3220                 rth = (struct ip6_rthdr *)buf;
3221                 rthlen = (rth->ip6r_len + 1) << 3;
3222                 if (len != rthlen)
3223                         return (EINVAL);
3224
3225                 switch (rth->ip6r_type) {
3226                 case IPV6_RTHDR_TYPE_0:
3227                         if (rth->ip6r_len == 0) /* must contain one addr */
3228                                 return (EINVAL);
3229                         if (rth->ip6r_len % 2) /* length must be even */
3230                                 return (EINVAL);
3231                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3232                                 return (EINVAL);
3233                         break;
3234                 default:
3235                         return (EINVAL);        /* not supported */
3236                 }
3237
3238                 /* turn off the previous option */
3239                 ip6_clearpktopts(opt, IPV6_RTHDR);
3240                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3241                 if (opt->ip6po_rthdr == NULL)
3242                         return (ENOBUFS);
3243                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3244
3245                 break;
3246         }
3247
3248         case IPV6_USE_MIN_MTU:
3249                 if (len != sizeof(int))
3250                         return (EINVAL);
3251                 minmtupolicy = *(int *)buf;
3252                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3253                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3254                     minmtupolicy != IP6PO_MINMTU_ALL) {
3255                         return (EINVAL);
3256                 }
3257                 opt->ip6po_minmtu = minmtupolicy;
3258                 break;
3259
3260         case IPV6_DONTFRAG:
3261                 if (len != sizeof(int))
3262                         return (EINVAL);
3263
3264                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3265                         /*
3266                          * we ignore this option for TCP sockets.
3267                          * (RFC3542 leaves this case unspecified.)
3268                          */
3269                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3270                 } else
3271                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3272                 break;
3273
3274         case IPV6_PREFER_TEMPADDR:
3275                 if (len != sizeof(int))
3276                         return (EINVAL);
3277                 preftemp = *(int *)buf;
3278                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3279                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3280                     preftemp != IP6PO_TEMPADDR_PREFER) {
3281                         return (EINVAL);
3282                 }
3283                 opt->ip6po_prefer_tempaddr = preftemp;
3284                 break;
3285
3286         default:
3287                 return (ENOPROTOOPT);
3288         } /* end of switch */
3289
3290         return (0);
3291 }
3292
3293 /*
3294  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3295  * packet to the input queue of a specified interface.  Note that this
3296  * calls the output routine of the loopback "driver", but with an interface
3297  * pointer that might NOT be &loif -- easier than replicating that code here.
3298  */
3299 void
3300 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3301 {
3302         struct mbuf *copym;
3303         struct ip6_hdr *ip6;
3304
3305         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3306         if (copym == NULL)
3307                 return;
3308
3309         /*
3310          * Make sure to deep-copy IPv6 header portion in case the data
3311          * is in an mbuf cluster, so that we can safely override the IPv6
3312          * header portion later.
3313          */
3314         if (!M_WRITABLE(copym) ||
3315             copym->m_len < sizeof(struct ip6_hdr)) {
3316                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3317                 if (copym == NULL)
3318                         return;
3319         }
3320         ip6 = mtod(copym, struct ip6_hdr *);
3321         /*
3322          * clear embedded scope identifiers if necessary.
3323          * in6_clearscope will touch the addresses only when necessary.
3324          */
3325         in6_clearscope(&ip6->ip6_src);
3326         in6_clearscope(&ip6->ip6_dst);
3327         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3328                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3329                     CSUM_PSEUDO_HDR;
3330                 copym->m_pkthdr.csum_data = 0xffff;
3331         }
3332         if_simloop(ifp, copym, AF_INET6, 0);
3333 }
3334
3335 /*
3336  * Chop IPv6 header off from the payload.
3337  */
3338 static int
3339 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3340 {
3341         struct mbuf *mh;
3342         struct ip6_hdr *ip6;
3343
3344         ip6 = mtod(m, struct ip6_hdr *);
3345         if (m->m_len > sizeof(*ip6)) {
3346                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3347                 if (mh == NULL) {
3348                         m_freem(m);
3349                         return ENOBUFS;
3350                 }
3351                 m_move_pkthdr(mh, m);
3352                 M_ALIGN(mh, sizeof(*ip6));
3353                 m->m_len -= sizeof(*ip6);
3354                 m->m_data += sizeof(*ip6);
3355                 mh->m_next = m;
3356                 m = mh;
3357                 m->m_len = sizeof(*ip6);
3358                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3359         }
3360         exthdrs->ip6e_ip6 = m;
3361         return 0;
3362 }
3363
3364 /*
3365  * Compute IPv6 extension header length.
3366  */
3367 int
3368 ip6_optlen(struct inpcb *inp)
3369 {
3370         int len;
3371
3372         if (!inp->in6p_outputopts)
3373                 return 0;
3374
3375         len = 0;
3376 #define elen(x) \
3377     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3378
3379         len += elen(inp->in6p_outputopts->ip6po_hbh);
3380         if (inp->in6p_outputopts->ip6po_rthdr)
3381                 /* dest1 is valid with rthdr only */
3382                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3383         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3384         len += elen(inp->in6p_outputopts->ip6po_dest2);
3385         return len;
3386 #undef elen
3387 }