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_llatbl.h>
  96 #include <net/netisr.h>
  97 #include <net/route.h>
  98 #include <net/route/nhop.h>
  99 #include <net/pfil.h>
 100 #include <net/rss_config.h>
 101 #include <net/vnet.h>
 102
 103 #include <netinet/in.h>
 104 #include <netinet/in_var.h>
 105 #include <netinet/ip_var.h>
 106 #include <netinet6/in6_fib.h>
 107 #include <netinet6/in6_var.h>
 108 #include <netinet/ip6.h>
 109 #include <netinet/icmp6.h>
 110 #include <netinet6/ip6_var.h>
 111 #include <netinet/in_pcb.h>
 112 #include <netinet/tcp_var.h>
 113 #include <netinet6/nd6.h>
 114 #include <netinet6/in6_rss.h>
 115
 116 #include <netipsec/ipsec_support.h>
 117 #if defined(SCTP) || defined(SCTP_SUPPORT)
 118 #include <netinet/sctp.h>
 119 #include <netinet/sctp_crc32.h>
 120 #endif
 121
 122 #include <netinet6/ip6protosw.h>
 123 #include <netinet6/scope6_var.h>
 124
 125 extern int in6_mcast_loop;
 126
 127 struct ip6_exthdrs {
 128         struct mbuf *ip6e_ip6;
 129         struct mbuf *ip6e_hbh;
 130         struct mbuf *ip6e_dest1;
 131         struct mbuf *ip6e_rthdr;
 132         struct mbuf *ip6e_dest2;
 133 };
 134
 135 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 136
 137 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 138                            struct ucred *, int);
 139 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 140         struct socket *, struct sockopt *);
 141 static int ip6_getpcbopt(struct inpcb *, int, struct sockopt *);
 142 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 143         struct ucred *, int, int, int);
 144
 145 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 146 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 147         struct ip6_frag **);
 148 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 149 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 150 static int ip6_getpmtu(struct route_in6 *, int,
 151         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int,
 152         u_int);
 153 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 154         u_long *, int *, u_int);
 155 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 156 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 157
 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 int
 215 ip6_output_delayed_csum(struct mbuf *m, struct ifnet *ifp, int csum_flags,
 216     int plen, int optlen, bool frag)
 217 {
 218
 219         KASSERT((plen >= optlen), ("%s:%d: plen %d < optlen %d, m %p, ifp %p "
 220             "csum_flags %#x frag %d\n",
 221             __func__, __LINE__, plen, optlen, m, ifp, csum_flags, frag));
 222
 223         if ((csum_flags & CSUM_DELAY_DATA_IPV6) ||
 224 #if defined(SCTP) || defined(SCTP_SUPPORT)
 225             (csum_flags & CSUM_SCTP_IPV6) ||
 226 #endif
 227             (!frag && (ifp->if_capenable & IFCAP_NOMAP) == 0)) {
 228                 m = mb_unmapped_to_ext(m);
 229                 if (m == NULL) {
 230                         if (frag)
 231                                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 232                         else
 233                                 IP6STAT_INC(ip6s_odropped);
 234                         return (ENOBUFS);
 235                 }
 236                 if (csum_flags & CSUM_DELAY_DATA_IPV6) {
 237                         in6_delayed_cksum(m, plen - optlen,
 238                             sizeof(struct ip6_hdr) + optlen);
 239                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 240                 }
 241 #if defined(SCTP) || defined(SCTP_SUPPORT)
 242                 if (csum_flags & CSUM_SCTP_IPV6) {
 243                         sctp_delayed_cksum(m, sizeof(struct ip6_hdr) + optlen);
 244                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 245                 }
 246 #endif
 247         }
 248
 249         return (0);
 250 }
 251
 252 int
 253 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 254     int fraglen , uint32_t id)
 255 {
 256         struct mbuf *m, **mnext, *m_frgpart;
 257         struct ip6_hdr *ip6, *mhip6;
 258         struct ip6_frag *ip6f;
 259         int off;
 260         int error;
 261         int tlen = m0->m_pkthdr.len;
 262
 263         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 264
 265         m = m0;
 266         ip6 = mtod(m, struct ip6_hdr *);
 267         mnext = &m->m_nextpkt;
 268
 269         for (off = hlen; off < tlen; off += fraglen) {
 270                 m = m_gethdr(M_NOWAIT, MT_DATA);
 271                 if (!m) {
 272                         IP6STAT_INC(ip6s_odropped);
 273                         return (ENOBUFS);
 274                 }
 275
 276                 /*
 277                  * Make sure the complete packet header gets copied
 278                  * from the originating mbuf to the newly created
 279                  * mbuf. This also ensures that existing firewall
 280                  * classification(s), VLAN tags and so on get copied
 281                  * to the resulting fragmented packet(s):
 282                  */
 283                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 284                         m_free(m);
 285                         IP6STAT_INC(ip6s_odropped);
 286                         return (ENOBUFS);
 287                 }
 288
 289                 *mnext = m;
 290                 mnext = &m->m_nextpkt;
 291                 m->m_data += max_linkhdr;
 292                 mhip6 = mtod(m, struct ip6_hdr *);
 293                 *mhip6 = *ip6;
 294                 m->m_len = sizeof(*mhip6);
 295                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 296                 if (error) {
 297                         IP6STAT_INC(ip6s_odropped);
 298                         return (error);
 299                 }
 300                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 301                 if (off + fraglen >= tlen)
 302                         fraglen = tlen - off;
 303                 else
 304                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 305                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 306                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 307                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 308                         IP6STAT_INC(ip6s_odropped);
 309                         return (ENOBUFS);
 310                 }
 311                 m_cat(m, m_frgpart);
 312                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 313                 ip6f->ip6f_reserved = 0;
 314                 ip6f->ip6f_ident = id;
 315                 ip6f->ip6f_nxt = nextproto;
 316                 IP6STAT_INC(ip6s_ofragments);
 317                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 318         }
 319
 320         return (0);
 321 }
 322
 323 static int
 324 ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp,
 325     struct mbuf *m, struct sockaddr_in6 *dst, struct route_in6 *ro,
 326     bool stamp_tag)
 327 {
 328 #ifdef KERN_TLS
 329         struct ktls_session *tls = NULL;
 330 #endif
 331         struct m_snd_tag *mst;
 332         int error;
 333
 334         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 335         mst = NULL;
 336
 337 #ifdef KERN_TLS
 338         /*
 339          * If this is an unencrypted TLS record, save a reference to
 340          * the record.  This local reference is used to call
 341          * ktls_output_eagain after the mbuf has been freed (thus
 342          * dropping the mbuf's reference) in if_output.
 343          */
 344         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 345                 tls = ktls_hold(m->m_next->m_epg_tls);
 346                 mst = tls->snd_tag;
 347
 348                 /*
 349                  * If a TLS session doesn't have a valid tag, it must
 350                  * have had an earlier ifp mismatch, so drop this
 351                  * packet.
 352                  */
 353                 if (mst == NULL) {
 354                         error = EAGAIN;
 355                         goto done;
 356                 }
 357                 /*
 358                  * Always stamp tags that include NIC ktls.
 359                  */
 360                 stamp_tag = true;
 361         }
 362 #endif
 363 #ifdef RATELIMIT
 364         if (inp != NULL && mst == NULL) {
 365                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 366                     (inp->inp_snd_tag != NULL &&
 367                     inp->inp_snd_tag->ifp != ifp))
 368                         in_pcboutput_txrtlmt(inp, ifp, m);
 369
 370                 if (inp->inp_snd_tag != NULL)
 371                         mst = inp->inp_snd_tag;
 372         }
 373 #endif
 374         if (stamp_tag && mst != NULL) {
 375                 KASSERT(m->m_pkthdr.rcvif == NULL,
 376                     ("trying to add a send tag to a forwarded packet"));
 377                 if (mst->ifp != ifp) {
 378                         error = EAGAIN;
 379                         goto done;
 380                 }
 381
 382                 /* stamp send tag on mbuf */
 383                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 384                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 385         }
 386
 387         error = nd6_output_ifp(ifp, origifp, m, dst, (struct route *)ro);
 388
 389 done:
 390         /* Check for route change invalidating send tags. */
 391 #ifdef KERN_TLS
 392         if (tls != NULL) {
 393                 if (error == EAGAIN)
 394                         error = ktls_output_eagain(inp, tls);
 395                 ktls_free(tls);
 396         }
 397 #endif
 398 #ifdef RATELIMIT
 399         if (error == EAGAIN)
 400                 in_pcboutput_eagain(inp);
 401 #endif
 402         return (error);
 403 }
 404
 405 /*
 406  * IP6 output.
 407  * The packet in mbuf chain m contains a skeletal IP6 header (with pri, len,
 408  * nxt, hlim, src, dst).
 409  * This function may modify ver and hlim only.
 410  * The mbuf chain containing the packet will be freed.
 411  * The mbuf opt, if present, will not be freed.
 412  * If route_in6 ro is present and has ro_nh initialized, route lookup would be
 413  * skipped and ro->ro_nh would be used. If ro is present but ro->ro_nh is NULL,
 414  * then result of route lookup is stored in ro->ro_nh.
 415  *
 416  * Type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and nd_ifinfo.linkmtu
 417  * is uint32_t.  So we use u_long to hold largest one, which is rt_mtu.
 418  *
 419  * ifpp - XXX: just for statistics
 420  */
 421 /*
 422  * XXX TODO: no flowid is assigned for outbound flows?
 423  */
 424 int
 425 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 426     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 427     struct ifnet **ifpp, struct inpcb *inp)
 428 {
 429         struct ip6_hdr *ip6;
 430         struct ifnet *ifp, *origifp;
 431         struct mbuf *m = m0;
 432         struct mbuf *mprev;
 433         struct route_in6 *ro_pmtu;
 434         struct nhop_object *nh;
 435         struct sockaddr_in6 *dst, sin6, src_sa, dst_sa;
 436         struct in6_addr odst;
 437         u_char *nexthdrp;
 438         int tlen, len;
 439         int error = 0;
 440         struct in6_ifaddr *ia = NULL;
 441         u_long mtu;
 442         int alwaysfrag, dontfrag;
 443         u_int32_t optlen, plen = 0, unfragpartlen;
 444         struct ip6_exthdrs exthdrs;
 445         struct in6_addr src0, dst0;
 446         u_int32_t zone;
 447         bool hdrsplit;
 448         int sw_csum, tso;
 449         int needfiblookup;
 450         uint32_t fibnum;
 451         struct m_tag *fwd_tag = NULL;
 452         uint32_t id;
 453
 454         NET_EPOCH_ASSERT();
 455
 456         if (inp != NULL) {
 457                 INP_LOCK_ASSERT(inp);
 458                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 459                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 460                         /* Unconditionally set flowid. */
 461                         m->m_pkthdr.flowid = inp->inp_flowid;
 462                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 463                 }
 464 #ifdef NUMA
 465                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 466 #endif
 467         }
 468
 469 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 470         /*
 471          * IPSec checking which handles several cases.
 472          * FAST IPSEC: We re-injected the packet.
 473          * XXX: need scope argument.
 474          */
 475         if (IPSEC_ENABLED(ipv6)) {
 476                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 477                         if (error == EINPROGRESS)
 478                                 error = 0;
 479                         goto done;
 480                 }
 481         }
 482 #endif /* IPSEC */
 483
 484         /* Source address validation. */
 485         ip6 = mtod(m, struct ip6_hdr *);
 486         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 487             (flags & IPV6_UNSPECSRC) == 0) {
 488                 error = EOPNOTSUPP;
 489                 IP6STAT_INC(ip6s_badscope);
 490                 goto bad;
 491         }
 492         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 493                 error = EOPNOTSUPP;
 494                 IP6STAT_INC(ip6s_badscope);
 495                 goto bad;
 496         }
 497
 498         /*
 499          * If we are given packet options to add extension headers prepare them.
 500          * Calculate the total length of the extension header chain.
 501          * Keep the length of the unfragmentable part for fragmentation.
 502          */
 503         bzero(&exthdrs, sizeof(exthdrs));
 504         optlen = 0;
 505         unfragpartlen = sizeof(struct ip6_hdr);
 506         if (opt) {
 507                 /* Hop-by-Hop options header. */
 508                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh, optlen);
 509
 510                 /* Destination options header (1st part). */
 511                 if (opt->ip6po_rthdr) {
 512 #ifndef RTHDR_SUPPORT_IMPLEMENTED
 513                         /*
 514                          * If there is a routing header, discard the packet
 515                          * right away here. RH0/1 are obsolete and we do not
 516                          * currently support RH2/3/4.
 517                          * People trying to use RH253/254 may want to disable
 518                          * this check.
 519                          * The moment we do support any routing header (again)
 520                          * this block should check the routing type more
 521                          * selectively.
 522                          */
 523                         error = EINVAL;
 524                         goto bad;
 525 #endif
 526
 527                         /*
 528                          * Destination options header (1st part).
 529                          * This only makes sense with a routing header.
 530                          * See Section 9.2 of RFC 3542.
 531                          * Disabling this part just for MIP6 convenience is
 532                          * a bad idea.  We need to think carefully about a
 533                          * way to make the advanced API coexist with MIP6
 534                          * options, which might automatically be inserted in
 535                          * the kernel.
 536                          */
 537                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1,
 538                             optlen);
 539                 }
 540                 /* Routing header. */
 541                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr, optlen);
 542
 543                 unfragpartlen += optlen;
 544
 545                 /*
 546                  * NOTE: we don't add AH/ESP length here (done in
 547                  * ip6_ipsec_output()).
 548                  */
 549
 550                 /* Destination options header (2nd part). */
 551                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2, optlen);
 552         }
 553
 554         /*
 555          * If there is at least one extension header,
 556          * separate IP6 header from the payload.
 557          */
 558         hdrsplit = false;
 559         if (optlen) {
 560                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 561                         m = NULL;
 562                         goto freehdrs;
 563                 }
 564                 m = exthdrs.ip6e_ip6;
 565                 ip6 = mtod(m, struct ip6_hdr *);
 566                 hdrsplit = true;
 567         }
 568
 569         /* Adjust mbuf packet header length. */
 570         m->m_pkthdr.len += optlen;
 571         plen = m->m_pkthdr.len - sizeof(*ip6);
 572
 573         /* If this is a jumbo payload, insert a jumbo payload option. */
 574         if (plen > IPV6_MAXPACKET) {
 575                 if (!hdrsplit) {
 576                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 577                                 m = NULL;
 578                                 goto freehdrs;
 579                         }
 580                         m = exthdrs.ip6e_ip6;
 581                         ip6 = mtod(m, struct ip6_hdr *);
 582                         hdrsplit = true;
 583                 }
 584                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 585                         goto freehdrs;
 586                 ip6->ip6_plen = 0;
 587         } else
 588                 ip6->ip6_plen = htons(plen);
 589         nexthdrp = &ip6->ip6_nxt;
 590
 591         if (optlen) {
 592                 /*
 593                  * Concatenate headers and fill in next header fields.
 594                  * Here we have, on "m"
 595                  *      IPv6 payload
 596                  * and we insert headers accordingly.
 597                  * Finally, we should be getting:
 598                  *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload].
 599                  *
 600                  * During the header composing process "m" points to IPv6
 601                  * header.  "mprev" points to an extension header prior to esp.
 602                  */
 603                 mprev = m;
 604
 605                 /*
 606                  * We treat dest2 specially.  This makes IPsec processing
 607                  * much easier.  The goal here is to make mprev point the
 608                  * mbuf prior to dest2.
 609                  *
 610                  * Result: IPv6 dest2 payload.
 611                  * m and mprev will point to IPv6 header.
 612                  */
 613                 if (exthdrs.ip6e_dest2) {
 614                         if (!hdrsplit)
 615                                 panic("%s:%d: assumption failed: "
 616                                     "hdr not split: hdrsplit %d exthdrs %p",
 617                                     __func__, __LINE__, hdrsplit, &exthdrs);
 618                         exthdrs.ip6e_dest2->m_next = m->m_next;
 619                         m->m_next = exthdrs.ip6e_dest2;
 620                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 621                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 622                 }
 623
 624                 /*
 625                  * Result: IPv6 hbh dest1 rthdr dest2 payload.
 626                  * m will point to IPv6 header.  mprev will point to the
 627                  * extension header prior to dest2 (rthdr in the above case).
 628                  */
 629                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 630                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 631                            IPPROTO_DSTOPTS);
 632                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 633                            IPPROTO_ROUTING);
 634         }
 635
 636         IP6STAT_INC(ip6s_localout);
 637
 638         /* Route packet. */
 639         ro_pmtu = ro;
 640         if (opt && opt->ip6po_rthdr)
 641                 ro = &opt->ip6po_route;
 642         if (ro != NULL)
 643                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 644         else
 645                 dst = &sin6;
 646         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 647
 648 again:
 649         /*
 650          * If specified, try to fill in the traffic class field.
 651          * Do not override if a non-zero value is already set.
 652          * We check the diffserv field and the ECN field separately.
 653          */
 654         if (opt && opt->ip6po_tclass >= 0) {
 655                 int mask = 0;
 656
 657                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 658                         mask |= 0xfc;
 659                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 660                         mask |= 0x03;
 661                 if (mask != 0)
 662                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 663         }
 664
 665         /* Fill in or override the hop limit field, if necessary. */
 666         if (opt && opt->ip6po_hlim != -1)
 667                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 668         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 669                 if (im6o != NULL)
 670                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 671                 else
 672                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 673         }
 674
 675         if (ro == NULL || ro->ro_nh == NULL) {
 676                 bzero(dst, sizeof(*dst));
 677                 dst->sin6_family = AF_INET6;
 678                 dst->sin6_len = sizeof(*dst);
 679                 dst->sin6_addr = ip6->ip6_dst;
 680         }
 681         /*
 682          * Validate route against routing table changes.
 683          * Make sure that the address family is set in route.
 684          */
 685         nh = NULL;
 686         ifp = NULL;
 687         mtu = 0;
 688         if (ro != NULL) {
 689                 if (ro->ro_nh != NULL && inp != NULL) {
 690                         ro->ro_dst.sin6_family = AF_INET6; /* XXX KASSERT? */
 691                         NH_VALIDATE((struct route *)ro, &inp->inp_rt_cookie,
 692                             fibnum);
 693                 }
 694                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 695                     (!NH_IS_VALID(ro->ro_nh) ||
 696                     ro->ro_dst.sin6_family != AF_INET6 ||
 697                     !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)))
 698                         RO_INVALIDATE_CACHE(ro);
 699
 700                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 701                     ro->ro_dst.sin6_family == AF_INET6 &&
 702                     IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 703                         nh = ro->ro_nh;
 704                         ifp = nh->nh_ifp;
 705                 } else {
 706                         if (ro->ro_lle)
 707                                 LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 708                         ro->ro_lle = NULL;
 709                         if (fwd_tag == NULL) {
 710                                 bzero(&dst_sa, sizeof(dst_sa));
 711                                 dst_sa.sin6_family = AF_INET6;
 712                                 dst_sa.sin6_len = sizeof(dst_sa);
 713                                 dst_sa.sin6_addr = ip6->ip6_dst;
 714                         }
 715                         error = in6_selectroute(&dst_sa, opt, im6o, ro, &ifp,
 716                             &nh, fibnum, m->m_pkthdr.flowid);
 717                         if (error != 0) {
 718                                 IP6STAT_INC(ip6s_noroute);
 719                                 if (ifp != NULL)
 720                                         in6_ifstat_inc(ifp, ifs6_out_discard);
 721                                 goto bad;
 722                         }
 723                         if (ifp != NULL)
 724                             mtu = ifp->if_mtu;
 725                 }
 726                 if (nh == NULL) {
 727                         /*
 728                          * If in6_selectroute() does not return a nexthop
 729                          * dst may not have been updated.
 730                          */
 731                         *dst = dst_sa;  /* XXX */
 732                 } else {
 733                         if (nh->nh_flags & NHF_HOST)
 734                             mtu = nh->nh_mtu;
 735                         ia = (struct in6_ifaddr *)(nh->nh_ifa);
 736                         counter_u64_add(nh->nh_pksent, 1);
 737                 }
 738         } else {
 739                 struct nhop_object *nh;
 740                 struct in6_addr kdst;
 741                 uint32_t scopeid;
 742
 743                 if (fwd_tag == NULL) {
 744                         bzero(&dst_sa, sizeof(dst_sa));
 745                         dst_sa.sin6_family = AF_INET6;
 746                         dst_sa.sin6_len = sizeof(dst_sa);
 747                         dst_sa.sin6_addr = ip6->ip6_dst;
 748                 }
 749
 750                 if (IN6_IS_ADDR_MULTICAST(&dst_sa.sin6_addr) &&
 751                     im6o != NULL &&
 752                     (ifp = im6o->im6o_multicast_ifp) != NULL) {
 753                         /* We do not need a route lookup. */
 754                         *dst = dst_sa;  /* XXX */
 755                         goto nonh6lookup;
 756                 }
 757
 758                 in6_splitscope(&dst_sa.sin6_addr, &kdst, &scopeid);
 759
 760                 if (IN6_IS_ADDR_MC_LINKLOCAL(&dst_sa.sin6_addr) ||
 761                     IN6_IS_ADDR_MC_NODELOCAL(&dst_sa.sin6_addr)) {
 762                         if (scopeid > 0) {
 763                                 ifp = in6_getlinkifnet(scopeid);
 764                                 *dst = dst_sa;  /* XXX */
 765                                 goto nonh6lookup;
 766                         }
 767                 }
 768
 769                 nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
 770                 if (nh == NULL) {
 771                         IP6STAT_INC(ip6s_noroute);
 772                         /* No ifp in6_ifstat_inc(ifp, ifs6_out_discard); */
 773                         error = EHOSTUNREACH;;
 774                         goto bad;
 775                 }
 776
 777                 ifp = nh->nh_ifp;
 778                 mtu = nh->nh_mtu;
 779                 ia = ifatoia6(nh->nh_ifa);
 780                 if (nh->nh_flags & NHF_GATEWAY)
 781                         dst->sin6_addr = nh->gw6_sa.sin6_addr;
 782 nonh6lookup:
 783                 ;
 784         }
 785
 786         /* Then nh (for unicast) and ifp must be non-NULL valid values. */
 787         if ((flags & IPV6_FORWARDING) == 0) {
 788                 /* XXX: the FORWARDING flag can be set for mrouting. */
 789                 in6_ifstat_inc(ifp, ifs6_out_request);
 790         }
 791
 792         /* Setup data structures for scope ID checks. */
 793         src0 = ip6->ip6_src;
 794         bzero(&src_sa, sizeof(src_sa));
 795         src_sa.sin6_family = AF_INET6;
 796         src_sa.sin6_len = sizeof(src_sa);
 797         src_sa.sin6_addr = ip6->ip6_src;
 798
 799         dst0 = ip6->ip6_dst;
 800         /* Re-initialize to be sure. */
 801         bzero(&dst_sa, sizeof(dst_sa));
 802         dst_sa.sin6_family = AF_INET6;
 803         dst_sa.sin6_len = sizeof(dst_sa);
 804         dst_sa.sin6_addr = ip6->ip6_dst;
 805
 806         /* Check for valid scope ID. */
 807         if (in6_setscope(&src0, ifp, &zone) == 0 &&
 808             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 809             in6_setscope(&dst0, ifp, &zone) == 0 &&
 810             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 811                 /*
 812                  * The outgoing interface is in the zone of the source
 813                  * and destination addresses.
 814                  *
 815                  * Because the loopback interface cannot receive
 816                  * packets with a different scope ID than its own,
 817                  * there is a trick to pretend the outgoing packet
 818                  * was received by the real network interface, by
 819                  * setting "origifp" different from "ifp". This is
 820                  * only allowed when "ifp" is a loopback network
 821                  * interface. Refer to code in nd6_output_ifp() for
 822                  * more details.
 823                  */
 824                 origifp = ifp;
 825
 826                 /*
 827                  * We should use ia_ifp to support the case of sending
 828                  * packets to an address of our own.
 829                  */
 830                 if (ia != NULL && ia->ia_ifp)
 831                         ifp = ia->ia_ifp;
 832
 833         } else if ((ifp->if_flags & IFF_LOOPBACK) == 0 ||
 834             sa6_recoverscope(&src_sa) != 0 ||
 835             sa6_recoverscope(&dst_sa) != 0 ||
 836             dst_sa.sin6_scope_id == 0 ||
 837             (src_sa.sin6_scope_id != 0 &&
 838             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 839             (origifp = ifnet_byindex(dst_sa.sin6_scope_id)) == NULL) {
 840                 /*
 841                  * If the destination network interface is not a
 842                  * loopback interface, or the destination network
 843                  * address has no scope ID, or the source address has
 844                  * a scope ID set which is different from the
 845                  * destination address one, or there is no network
 846                  * interface representing this scope ID, the address
 847                  * pair is considered invalid.
 848                  */
 849                 IP6STAT_INC(ip6s_badscope);
 850                 in6_ifstat_inc(ifp, ifs6_out_discard);
 851                 if (error == 0)
 852                         error = EHOSTUNREACH; /* XXX */
 853                 goto bad;
 854         }
 855         /* All scope ID checks are successful. */
 856
 857         if (nh && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 858                 if (opt && opt->ip6po_nextroute.ro_nh) {
 859                         /*
 860                          * The nexthop is explicitly specified by the
 861                          * application.  We assume the next hop is an IPv6
 862                          * address.
 863                          */
 864                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 865                 }
 866                 else if ((nh->nh_flags & NHF_GATEWAY))
 867                         dst = &nh->gw6_sa;
 868         }
 869
 870         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 871                 m->m_flags &= ~(M_BCAST | M_MCAST); /* Just in case. */
 872         } else {
 873                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 874                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 875
 876                 /* Confirm that the outgoing interface supports multicast. */
 877                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 878                         IP6STAT_INC(ip6s_noroute);
 879                         in6_ifstat_inc(ifp, ifs6_out_discard);
 880                         error = ENETUNREACH;
 881                         goto bad;
 882                 }
 883                 if ((im6o == NULL && in6_mcast_loop) ||
 884                     (im6o && im6o->im6o_multicast_loop)) {
 885                         /*
 886                          * Loop back multicast datagram if not expressly
 887                          * forbidden to do so, even if we have not joined
 888                          * the address; protocols will filter it later,
 889                          * thus deferring a hash lookup and lock acquisition
 890                          * at the expense of an m_copym().
 891                          */
 892                         ip6_mloopback(ifp, m);
 893                 } else {
 894                         /*
 895                          * If we are acting as a multicast router, perform
 896                          * multicast forwarding as if the packet had just
 897                          * arrived on the interface to which we are about
 898                          * to send.  The multicast forwarding function
 899                          * recursively calls this function, using the
 900                          * IPV6_FORWARDING flag to prevent infinite recursion.
 901                          *
 902                          * Multicasts that are looped back by ip6_mloopback(),
 903                          * above, will be forwarded by the ip6_input() routine,
 904                          * if necessary.
 905                          */
 906                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 907                                 /*
 908                                  * XXX: ip6_mforward expects that rcvif is NULL
 909                                  * when it is called from the originating path.
 910                                  * However, it may not always be the case.
 911                                  */
 912                                 m->m_pkthdr.rcvif = NULL;
 913                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 914                                         m_freem(m);
 915                                         goto done;
 916                                 }
 917                         }
 918                 }
 919                 /*
 920                  * Multicasts with a hoplimit of zero may be looped back,
 921                  * above, but must not be transmitted on a network.
 922                  * Also, multicasts addressed to the loopback interface
 923                  * are not sent -- the above call to ip6_mloopback() will
 924                  * loop back a copy if this host actually belongs to the
 925                  * destination group on the loopback interface.
 926                  */
 927                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 928                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 929                         m_freem(m);
 930                         goto done;
 931                 }
 932         }
 933
 934         /*
 935          * Fill the outgoing inteface to tell the upper layer
 936          * to increment per-interface statistics.
 937          */
 938         if (ifpp)
 939                 *ifpp = ifp;
 940
 941         /* Determine path MTU. */
 942         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 943                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 944                 goto bad;
 945         KASSERT(mtu > 0, ("%s:%d: mtu %ld, ro_pmtu %p ro %p ifp %p "
 946             "alwaysfrag %d fibnum %u\n", __func__, __LINE__, mtu, ro_pmtu, ro,
 947             ifp, alwaysfrag, fibnum));
 948
 949         /*
 950          * The caller of this function may specify to use the minimum MTU
 951          * in some cases.
 952          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 953          * setting.  The logic is a bit complicated; by default, unicast
 954          * packets will follow path MTU while multicast packets will be sent at
 955          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 956          * including unicast ones will be sent at the minimum MTU.  Multicast
 957          * packets will always be sent at the minimum MTU unless
 958          * IP6PO_MINMTU_DISABLE is explicitly specified.
 959          * See RFC 3542 for more details.
 960          */
 961         if (mtu > IPV6_MMTU) {
 962                 if ((flags & IPV6_MINMTU))
 963                         mtu = IPV6_MMTU;
 964                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 965                         mtu = IPV6_MMTU;
 966                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 967                          (opt == NULL ||
 968                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 969                         mtu = IPV6_MMTU;
 970                 }
 971         }
 972
 973         /*
 974          * Clear embedded scope identifiers if necessary.
 975          * in6_clearscope() will touch the addresses only when necessary.
 976          */
 977         in6_clearscope(&ip6->ip6_src);
 978         in6_clearscope(&ip6->ip6_dst);
 979
 980         /*
 981          * If the outgoing packet contains a hop-by-hop options header,
 982          * it must be examined and processed even by the source node.
 983          * (RFC 2460, section 4.)
 984          */
 985         if (exthdrs.ip6e_hbh) {
 986                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 987                 u_int32_t dummy; /* XXX unused */
 988                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 989
 990 #ifdef DIAGNOSTIC
 991                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 992                         panic("ip6e_hbh is not contiguous");
 993 #endif
 994                 /*
 995                  *  XXX: if we have to send an ICMPv6 error to the sender,
 996                  *       we need the M_LOOP flag since icmp6_error() expects
 997                  *       the IPv6 and the hop-by-hop options header are
 998                  *       contiguous unless the flag is set.
 999                  */
1000                 m->m_flags |= M_LOOP;
1001                 m->m_pkthdr.rcvif = ifp;
1002                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
1003                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
1004                     &dummy, &plen) < 0) {
1005                         /* m was already freed at this point. */
1006                         error = EINVAL;/* better error? */
1007                         goto done;
1008                 }
1009                 m->m_flags &= ~M_LOOP; /* XXX */
1010                 m->m_pkthdr.rcvif = NULL;
1011         }
1012
1013         /* Jump over all PFIL processing if hooks are not active. */
1014         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
1015                 goto passout;
1016
1017         odst = ip6->ip6_dst;
1018         /* Run through list of hooks for output packets. */
1019         switch (pfil_run_hooks(V_inet6_pfil_head, &m, ifp, PFIL_OUT, inp)) {
1020         case PFIL_PASS:
1021                 ip6 = mtod(m, struct ip6_hdr *);
1022                 break;
1023         case PFIL_DROPPED:
1024                 error = EACCES;
1025                 /* FALLTHROUGH */
1026         case PFIL_CONSUMED:
1027                 goto done;
1028         }
1029
1030         needfiblookup = 0;
1031         /* See if destination IP address was changed by packet filter. */
1032         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
1033                 m->m_flags |= M_SKIP_FIREWALL;
1034                 /* If destination is now ourself drop to ip6_input(). */
1035                 if (in6_localip(&ip6->ip6_dst)) {
1036                         m->m_flags |= M_FASTFWD_OURS;
1037                         if (m->m_pkthdr.rcvif == NULL)
1038                                 m->m_pkthdr.rcvif = V_loif;
1039                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1040                                 m->m_pkthdr.csum_flags |=
1041                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1042                                 m->m_pkthdr.csum_data = 0xffff;
1043                         }
1044 #if defined(SCTP) || defined(SCTP_SUPPORT)
1045                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1046                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1047 #endif
1048                         error = netisr_queue(NETISR_IPV6, m);
1049                         goto done;
1050                 } else {
1051                         if (ro != NULL)
1052                                 RO_INVALIDATE_CACHE(ro);
1053                         needfiblookup = 1; /* Redo the routing table lookup. */
1054                 }
1055         }
1056         /* See if fib was changed by packet filter. */
1057         if (fibnum != M_GETFIB(m)) {
1058                 m->m_flags |= M_SKIP_FIREWALL;
1059                 fibnum = M_GETFIB(m);
1060                 if (ro != NULL)
1061                         RO_INVALIDATE_CACHE(ro);
1062                 needfiblookup = 1;
1063         }
1064         if (needfiblookup)
1065                 goto again;
1066
1067         /* See if local, if yes, send it to netisr. */
1068         if (m->m_flags & M_FASTFWD_OURS) {
1069                 if (m->m_pkthdr.rcvif == NULL)
1070                         m->m_pkthdr.rcvif = V_loif;
1071                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1072                         m->m_pkthdr.csum_flags |=
1073                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1074                         m->m_pkthdr.csum_data = 0xffff;
1075                 }
1076 #if defined(SCTP) || defined(SCTP_SUPPORT)
1077                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1078                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1079 #endif
1080                 error = netisr_queue(NETISR_IPV6, m);
1081                 goto done;
1082         }
1083         /* Or forward to some other address? */
1084         if ((m->m_flags & M_IP6_NEXTHOP) &&
1085             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
1086                 if (ro != NULL)
1087                         dst = (struct sockaddr_in6 *)&ro->ro_dst;
1088                 else
1089                         dst = &sin6;
1090                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
1091                 m->m_flags |= M_SKIP_FIREWALL;
1092                 m->m_flags &= ~M_IP6_NEXTHOP;
1093                 m_tag_delete(m, fwd_tag);
1094                 goto again;
1095         }
1096
1097 passout:
1098         /*
1099          * Send the packet to the outgoing interface.
1100          * If necessary, do IPv6 fragmentation before sending.
1101          *
1102          * The logic here is rather complex:
1103          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
1104          * 1-a: send as is if tlen <= path mtu
1105          * 1-b: fragment if tlen > path mtu
1106          *
1107          * 2: if user asks us not to fragment (dontfrag == 1)
1108          * 2-a: send as is if tlen <= interface mtu
1109          * 2-b: error if tlen > interface mtu
1110          *
1111          * 3: if we always need to attach fragment header (alwaysfrag == 1)
1112          *      always fragment
1113          *
1114          * 4: if dontfrag == 1 && alwaysfrag == 1
1115          *      error, as we cannot handle this conflicting request.
1116          */
1117         sw_csum = m->m_pkthdr.csum_flags;
1118         if (!hdrsplit) {
1119                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
1120                 sw_csum &= ~ifp->if_hwassist;
1121         } else
1122                 tso = 0;
1123         /*
1124          * If we added extension headers, we will not do TSO and calculate the
1125          * checksums ourselves for now.
1126          * XXX-BZ  Need a framework to know when the NIC can handle it, even
1127          * with ext. hdrs.
1128          */
1129         error = ip6_output_delayed_csum(m, ifp, sw_csum, plen, optlen, false);
1130         if (error != 0)
1131                 goto bad;
1132         /* XXX-BZ m->m_pkthdr.csum_flags &= ~ifp->if_hwassist; */
1133         tlen = m->m_pkthdr.len;
1134
1135         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1136                 dontfrag = 1;
1137         else
1138                 dontfrag = 0;
1139         if (dontfrag && alwaysfrag) {   /* Case 4. */
1140                 /* Conflicting request - can't transmit. */
1141                 error = EMSGSIZE;
1142                 goto bad;
1143         }
1144         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* Case 2-b. */
1145                 /*
1146                  * Even if the DONTFRAG option is specified, we cannot send the
1147                  * packet when the data length is larger than the MTU of the
1148                  * outgoing interface.
1149                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1150                  * application wanted to know the MTU value. Also return an
1151                  * error code (this is not described in the API spec).
1152                  */
1153                 if (inp != NULL)
1154                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1155                 error = EMSGSIZE;
1156                 goto bad;
1157         }
1158
1159         /* Transmit packet without fragmentation. */
1160         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* Cases 1-a and 2-a. */
1161                 struct in6_ifaddr *ia6;
1162
1163                 ip6 = mtod(m, struct ip6_hdr *);
1164                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1165                 if (ia6) {
1166                         /* Record statistics for this interface address. */
1167                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1168                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1169                             m->m_pkthdr.len);
1170                         ifa_free(&ia6->ia_ifa);
1171                 }
1172                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1173                     (flags & IP_NO_SND_TAG_RL) ? false : true);
1174                 goto done;
1175         }
1176
1177         /* Try to fragment the packet.  Cases 1-b and 3. */
1178         if (mtu < IPV6_MMTU) {
1179                 /* Path MTU cannot be less than IPV6_MMTU. */
1180                 error = EMSGSIZE;
1181                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1182                 goto bad;
1183         } else if (ip6->ip6_plen == 0) {
1184                 /* Jumbo payload cannot be fragmented. */
1185                 error = EMSGSIZE;
1186                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1187                 goto bad;
1188         } else {
1189                 u_char nextproto;
1190
1191                 /*
1192                  * Too large for the destination or interface;
1193                  * fragment if possible.
1194                  * Must be able to put at least 8 bytes per fragment.
1195                  */
1196                 if (mtu > IPV6_MAXPACKET)
1197                         mtu = IPV6_MAXPACKET;
1198
1199                 len = (mtu - unfragpartlen - sizeof(struct ip6_frag)) & ~7;
1200                 if (len < 8) {
1201                         error = EMSGSIZE;
1202                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1203                         goto bad;
1204                 }
1205
1206                 /*
1207                  * If the interface will not calculate checksums on
1208                  * fragmented packets, then do it here.
1209                  * XXX-BZ handle the hw offloading case.  Need flags.
1210                  */
1211                 error = ip6_output_delayed_csum(m, ifp, m->m_pkthdr.csum_flags,
1212                     plen, optlen, true);
1213                 if (error != 0)
1214                         goto bad;
1215
1216                 /*
1217                  * Change the next header field of the last header in the
1218                  * unfragmentable part.
1219                  */
1220                 if (exthdrs.ip6e_rthdr) {
1221                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1222                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1223                 } else if (exthdrs.ip6e_dest1) {
1224                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1225                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1226                 } else if (exthdrs.ip6e_hbh) {
1227                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1228                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1229                 } else {
1230                         ip6 = mtod(m, struct ip6_hdr *);
1231                         nextproto = ip6->ip6_nxt;
1232                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1233                 }
1234
1235                 /*
1236                  * Loop through length of segment after first fragment,
1237                  * make new header and copy data of each part and link onto
1238                  * chain.
1239                  */
1240                 m0 = m;
1241                 id = htonl(ip6_randomid());
1242                 error = ip6_fragment(ifp, m, unfragpartlen, nextproto,len, id);
1243                 if (error != 0)
1244                         goto sendorfree;
1245
1246                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1247         }
1248
1249         /* Remove leading garbage. */
1250 sendorfree:
1251         m = m0->m_nextpkt;
1252         m0->m_nextpkt = 0;
1253         m_freem(m0);
1254         for (; m; m = m0) {
1255                 m0 = m->m_nextpkt;
1256                 m->m_nextpkt = 0;
1257                 if (error == 0) {
1258                         /* Record statistics for this interface address. */
1259                         if (ia) {
1260                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1261                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1262                                     m->m_pkthdr.len);
1263                         }
1264                         error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1265                             true);
1266                 } else
1267                         m_freem(m);
1268         }
1269
1270         if (error == 0)
1271                 IP6STAT_INC(ip6s_fragmented);
1272
1273 done:
1274         return (error);
1275
1276 freehdrs:
1277         m_freem(exthdrs.ip6e_hbh);      /* m_freem() checks if mbuf is NULL. */
1278         m_freem(exthdrs.ip6e_dest1);
1279         m_freem(exthdrs.ip6e_rthdr);
1280         m_freem(exthdrs.ip6e_dest2);
1281         /* FALLTHROUGH */
1282 bad:
1283         if (m)
1284                 m_freem(m);
1285         goto done;
1286 }
1287
1288 static int
1289 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1290 {
1291         struct mbuf *m;
1292
1293         if (hlen > MCLBYTES)
1294                 return (ENOBUFS); /* XXX */
1295
1296         if (hlen > MLEN)
1297                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1298         else
1299                 m = m_get(M_NOWAIT, MT_DATA);
1300         if (m == NULL)
1301                 return (ENOBUFS);
1302         m->m_len = hlen;
1303         if (hdr)
1304                 bcopy(hdr, mtod(m, caddr_t), hlen);
1305
1306         *mp = m;
1307         return (0);
1308 }
1309
1310 /*
1311  * Insert jumbo payload option.
1312  */
1313 static int
1314 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1315 {
1316         struct mbuf *mopt;
1317         u_char *optbuf;
1318         u_int32_t v;
1319
1320 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1321
1322         /*
1323          * If there is no hop-by-hop options header, allocate new one.
1324          * If there is one but it doesn't have enough space to store the
1325          * jumbo payload option, allocate a cluster to store the whole options.
1326          * Otherwise, use it to store the options.
1327          */
1328         if (exthdrs->ip6e_hbh == NULL) {
1329                 mopt = m_get(M_NOWAIT, MT_DATA);
1330                 if (mopt == NULL)
1331                         return (ENOBUFS);
1332                 mopt->m_len = JUMBOOPTLEN;
1333                 optbuf = mtod(mopt, u_char *);
1334                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1335                 exthdrs->ip6e_hbh = mopt;
1336         } else {
1337                 struct ip6_hbh *hbh;
1338
1339                 mopt = exthdrs->ip6e_hbh;
1340                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1341                         /*
1342                          * XXX assumption:
1343                          * - exthdrs->ip6e_hbh is not referenced from places
1344                          *   other than exthdrs.
1345                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1346                          */
1347                         int oldoptlen = mopt->m_len;
1348                         struct mbuf *n;
1349
1350                         /*
1351                          * XXX: give up if the whole (new) hbh header does
1352                          * not fit even in an mbuf cluster.
1353                          */
1354                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1355                                 return (ENOBUFS);
1356
1357                         /*
1358                          * As a consequence, we must always prepare a cluster
1359                          * at this point.
1360                          */
1361                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1362                         if (n == NULL)
1363                                 return (ENOBUFS);
1364                         n->m_len = oldoptlen + JUMBOOPTLEN;
1365                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1366                             oldoptlen);
1367                         optbuf = mtod(n, caddr_t) + oldoptlen;
1368                         m_freem(mopt);
1369                         mopt = exthdrs->ip6e_hbh = n;
1370                 } else {
1371                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1372                         mopt->m_len += JUMBOOPTLEN;
1373                 }
1374                 optbuf[0] = IP6OPT_PADN;
1375                 optbuf[1] = 1;
1376
1377                 /*
1378                  * Adjust the header length according to the pad and
1379                  * the jumbo payload option.
1380                  */
1381                 hbh = mtod(mopt, struct ip6_hbh *);
1382                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1383         }
1384
1385         /* fill in the option. */
1386         optbuf[2] = IP6OPT_JUMBO;
1387         optbuf[3] = 4;
1388         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1389         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1390
1391         /* finally, adjust the packet header length */
1392         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1393
1394         return (0);
1395 #undef JUMBOOPTLEN
1396 }
1397
1398 /*
1399  * Insert fragment header and copy unfragmentable header portions.
1400  */
1401 static int
1402 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1403     struct ip6_frag **frghdrp)
1404 {
1405         struct mbuf *n, *mlast;
1406
1407         if (hlen > sizeof(struct ip6_hdr)) {
1408                 n = m_copym(m0, sizeof(struct ip6_hdr),
1409                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1410                 if (n == NULL)
1411                         return (ENOBUFS);
1412                 m->m_next = n;
1413         } else
1414                 n = m;
1415
1416         /* Search for the last mbuf of unfragmentable part. */
1417         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1418                 ;
1419
1420         if (M_WRITABLE(mlast) &&
1421             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1422                 /* use the trailing space of the last mbuf for the fragment hdr */
1423                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1424                     mlast->m_len);
1425                 mlast->m_len += sizeof(struct ip6_frag);
1426                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1427         } else {
1428                 /* allocate a new mbuf for the fragment header */
1429                 struct mbuf *mfrg;
1430
1431                 mfrg = m_get(M_NOWAIT, MT_DATA);
1432                 if (mfrg == NULL)
1433                         return (ENOBUFS);
1434                 mfrg->m_len = sizeof(struct ip6_frag);
1435                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1436                 mlast->m_next = mfrg;
1437         }
1438
1439         return (0);
1440 }
1441
1442 /*
1443  * Calculates IPv6 path mtu for destination @dst.
1444  * Resulting MTU is stored in @mtup.
1445  *
1446  * Returns 0 on success.
1447  */
1448 static int
1449 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1450 {
1451         struct epoch_tracker et;
1452         struct nhop_object *nh;
1453         struct in6_addr kdst;
1454         uint32_t scopeid;
1455         int error;
1456
1457         in6_splitscope(dst, &kdst, &scopeid);
1458
1459         NET_EPOCH_ENTER(et);
1460         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1461         if (nh != NULL)
1462                 error = ip6_calcmtu(nh->nh_ifp, dst, nh->nh_mtu, mtup, NULL, 0);
1463         else
1464                 error = EHOSTUNREACH;
1465         NET_EPOCH_EXIT(et);
1466
1467         return (error);
1468 }
1469
1470 /*
1471  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1472  * and cached data in @ro_pmtu.
1473  * MTU from (successful) route lookup is saved (along with dst)
1474  * inside @ro_pmtu to avoid subsequent route lookups after packet
1475  * filter processing.
1476  *
1477  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1478  * Returns 0 on success.
1479  */
1480 static int
1481 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1482     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1483     int *alwaysfragp, u_int fibnum, u_int proto)
1484 {
1485         struct nhop_object *nh;
1486         struct in6_addr kdst;
1487         uint32_t scopeid;
1488         struct sockaddr_in6 *sa6_dst, sin6;
1489         u_long mtu;
1490
1491         NET_EPOCH_ASSERT();
1492
1493         mtu = 0;
1494         if (ro_pmtu == NULL || do_lookup) {
1495
1496                 /*
1497                  * Here ro_pmtu has final destination address, while
1498                  * ro might represent immediate destination.
1499                  * Use ro_pmtu destination since mtu might differ.
1500                  */
1501                 if (ro_pmtu != NULL) {
1502                         sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1503                         if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1504                                 ro_pmtu->ro_mtu = 0;
1505                 } else
1506                         sa6_dst = &sin6;
1507
1508                 if (ro_pmtu == NULL || ro_pmtu->ro_mtu == 0) {
1509                         bzero(sa6_dst, sizeof(*sa6_dst));
1510                         sa6_dst->sin6_family = AF_INET6;
1511                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1512                         sa6_dst->sin6_addr = *dst;
1513
1514                         in6_splitscope(dst, &kdst, &scopeid);
1515                         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1516                         if (nh != NULL) {
1517                                 mtu = nh->nh_mtu;
1518                                 if (ro_pmtu != NULL)
1519                                         ro_pmtu->ro_mtu = mtu;
1520                         }
1521                 } else
1522                         mtu = ro_pmtu->ro_mtu;
1523         }
1524
1525         if (ro_pmtu != NULL && ro_pmtu->ro_nh != NULL)
1526                 mtu = ro_pmtu->ro_nh->nh_mtu;
1527
1528         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1529 }
1530
1531 /*
1532  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1533  * hostcache data for @dst.
1534  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1535  *
1536  * Returns 0 on success.
1537  */
1538 static int
1539 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1540     u_long *mtup, int *alwaysfragp, u_int proto)
1541 {
1542         u_long mtu = 0;
1543         int alwaysfrag = 0;
1544         int error = 0;
1545
1546         if (rt_mtu > 0) {
1547                 u_int32_t ifmtu;
1548                 struct in_conninfo inc;
1549
1550                 bzero(&inc, sizeof(inc));
1551                 inc.inc_flags |= INC_ISIPV6;
1552                 inc.inc6_faddr = *dst;
1553
1554                 ifmtu = IN6_LINKMTU(ifp);
1555
1556                 /* TCP is known to react to pmtu changes so skip hc */
1557                 if (proto != IPPROTO_TCP)
1558                         mtu = tcp_hc_getmtu(&inc);
1559
1560                 if (mtu)
1561                         mtu = min(mtu, rt_mtu);
1562                 else
1563                         mtu = rt_mtu;
1564                 if (mtu == 0)
1565                         mtu = ifmtu;
1566                 else if (mtu < IPV6_MMTU) {
1567                         /*
1568                          * RFC2460 section 5, last paragraph:
1569                          * if we record ICMPv6 too big message with
1570                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1571                          * or smaller, with framgent header attached.
1572                          * (fragment header is needed regardless from the
1573                          * packet size, for translators to identify packets)
1574                          */
1575                         alwaysfrag = 1;
1576                         mtu = IPV6_MMTU;
1577                 }
1578         } else if (ifp) {
1579                 mtu = IN6_LINKMTU(ifp);
1580         } else
1581                 error = EHOSTUNREACH; /* XXX */
1582
1583         *mtup = mtu;
1584         if (alwaysfragp)
1585                 *alwaysfragp = alwaysfrag;
1586         return (error);
1587 }
1588
1589 /*
1590  * IP6 socket option processing.
1591  */
1592 int
1593 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1594 {
1595         int optdatalen, uproto;
1596         void *optdata;
1597         struct inpcb *inp = sotoinpcb(so);
1598         int error, optval;
1599         int level, op, optname;
1600         int optlen;
1601         struct thread *td;
1602 #ifdef  RSS
1603         uint32_t rss_bucket;
1604         int retval;
1605 #endif
1606
1607 /*
1608  * Don't use more than a quarter of mbuf clusters.  N.B.:
1609  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1610  * on LP64 architectures, so cast to u_long to avoid undefined
1611  * behavior.  ILP32 architectures cannot have nmbclusters
1612  * large enough to overflow for other reasons.
1613  */
1614 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1615
1616         level = sopt->sopt_level;
1617         op = sopt->sopt_dir;
1618         optname = sopt->sopt_name;
1619         optlen = sopt->sopt_valsize;
1620         td = sopt->sopt_td;
1621         error = 0;
1622         optval = 0;
1623         uproto = (int)so->so_proto->pr_protocol;
1624
1625         if (level != IPPROTO_IPV6) {
1626                 error = EINVAL;
1627
1628                 if (sopt->sopt_level == SOL_SOCKET &&
1629                     sopt->sopt_dir == SOPT_SET) {
1630                         switch (sopt->sopt_name) {
1631                         case SO_REUSEADDR:
1632                                 INP_WLOCK(inp);
1633                                 if ((so->so_options & SO_REUSEADDR) != 0)
1634                                         inp->inp_flags2 |= INP_REUSEADDR;
1635                                 else
1636                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1637                                 INP_WUNLOCK(inp);
1638                                 error = 0;
1639                                 break;
1640                         case SO_REUSEPORT:
1641                                 INP_WLOCK(inp);
1642                                 if ((so->so_options & SO_REUSEPORT) != 0)
1643                                         inp->inp_flags2 |= INP_REUSEPORT;
1644                                 else
1645                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1646                                 INP_WUNLOCK(inp);
1647                                 error = 0;
1648                                 break;
1649                         case SO_REUSEPORT_LB:
1650                                 INP_WLOCK(inp);
1651                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1652                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1653                                 else
1654                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1655                                 INP_WUNLOCK(inp);
1656                                 error = 0;
1657                                 break;
1658                         case SO_SETFIB:
1659                                 INP_WLOCK(inp);
1660                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1661                                 INP_WUNLOCK(inp);
1662                                 error = 0;
1663                                 break;
1664                         case SO_MAX_PACING_RATE:
1665 #ifdef RATELIMIT
1666                                 INP_WLOCK(inp);
1667                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1668                                 INP_WUNLOCK(inp);
1669                                 error = 0;
1670 #else
1671                                 error = EOPNOTSUPP;
1672 #endif
1673                                 break;
1674                         default:
1675                                 break;
1676                         }
1677                 }
1678         } else {                /* level == IPPROTO_IPV6 */
1679                 switch (op) {
1680
1681                 case SOPT_SET:
1682                         switch (optname) {
1683                         case IPV6_2292PKTOPTIONS:
1684 #ifdef IPV6_PKTOPTIONS
1685                         case IPV6_PKTOPTIONS:
1686 #endif
1687                         {
1688                                 struct mbuf *m;
1689
1690                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1691                                         printf("ip6_ctloutput: mbuf limit hit\n");
1692                                         error = ENOBUFS;
1693                                         break;
1694                                 }
1695
1696                                 error = soopt_getm(sopt, &m); /* XXX */
1697                                 if (error != 0)
1698                                         break;
1699                                 error = soopt_mcopyin(sopt, m); /* XXX */
1700                                 if (error != 0)
1701                                         break;
1702                                 INP_WLOCK(inp);
1703                                 error = ip6_pcbopts(&inp->in6p_outputopts, m,
1704                                     so, sopt);
1705                                 INP_WUNLOCK(inp);
1706                                 m_freem(m); /* XXX */
1707                                 break;
1708                         }
1709
1710                         /*
1711                          * Use of some Hop-by-Hop options or some
1712                          * Destination options, might require special
1713                          * privilege.  That is, normal applications
1714                          * (without special privilege) might be forbidden
1715                          * from setting certain options in outgoing packets,
1716                          * and might never see certain options in received
1717                          * packets. [RFC 2292 Section 6]
1718                          * KAME specific note:
1719                          *  KAME prevents non-privileged users from sending or
1720                          *  receiving ANY hbh/dst options in order to avoid
1721                          *  overhead of parsing options in the kernel.
1722                          */
1723                         case IPV6_RECVHOPOPTS:
1724                         case IPV6_RECVDSTOPTS:
1725                         case IPV6_RECVRTHDRDSTOPTS:
1726                                 if (td != NULL) {
1727                                         error = priv_check(td,
1728                                             PRIV_NETINET_SETHDROPTS);
1729                                         if (error)
1730                                                 break;
1731                                 }
1732                                 /* FALLTHROUGH */
1733                         case IPV6_UNICAST_HOPS:
1734                         case IPV6_HOPLIMIT:
1735
1736                         case IPV6_RECVPKTINFO:
1737                         case IPV6_RECVHOPLIMIT:
1738                         case IPV6_RECVRTHDR:
1739                         case IPV6_RECVPATHMTU:
1740                         case IPV6_RECVTCLASS:
1741                         case IPV6_RECVFLOWID:
1742 #ifdef  RSS
1743                         case IPV6_RECVRSSBUCKETID:
1744 #endif
1745                         case IPV6_V6ONLY:
1746                         case IPV6_AUTOFLOWLABEL:
1747                         case IPV6_ORIGDSTADDR:
1748                         case IPV6_BINDANY:
1749                         case IPV6_BINDMULTI:
1750 #ifdef  RSS
1751                         case IPV6_RSS_LISTEN_BUCKET:
1752 #endif
1753                                 if (optname == IPV6_BINDANY && td != NULL) {
1754                                         error = priv_check(td,
1755                                             PRIV_NETINET_BINDANY);
1756                                         if (error)
1757                                                 break;
1758                                 }
1759
1760                                 if (optlen != sizeof(int)) {
1761                                         error = EINVAL;
1762                                         break;
1763                                 }
1764                                 error = sooptcopyin(sopt, &optval,
1765                                         sizeof optval, sizeof optval);
1766                                 if (error)
1767                                         break;
1768                                 switch (optname) {
1769
1770                                 case IPV6_UNICAST_HOPS:
1771                                         if (optval < -1 || optval >= 256)
1772                                                 error = EINVAL;
1773                                         else {
1774                                                 /* -1 = kernel default */
1775                                                 inp->in6p_hops = optval;
1776                                                 if ((inp->inp_vflag &
1777                                                      INP_IPV4) != 0)
1778                                                         inp->inp_ip_ttl = optval;
1779                                         }
1780                                         break;
1781 #define OPTSET(bit) \
1782 do { \
1783         INP_WLOCK(inp); \
1784         if (optval) \
1785                 inp->inp_flags |= (bit); \
1786         else \
1787                 inp->inp_flags &= ~(bit); \
1788         INP_WUNLOCK(inp); \
1789 } while (/*CONSTCOND*/ 0)
1790 #define OPTSET2292(bit) \
1791 do { \
1792         INP_WLOCK(inp); \
1793         inp->inp_flags |= IN6P_RFC2292; \
1794         if (optval) \
1795                 inp->inp_flags |= (bit); \
1796         else \
1797                 inp->inp_flags &= ~(bit); \
1798         INP_WUNLOCK(inp); \
1799 } while (/*CONSTCOND*/ 0)
1800 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1801
1802 #define OPTSET2_N(bit, val) do {                                        \
1803         if (val)                                                        \
1804                 inp->inp_flags2 |= bit;                                 \
1805         else                                                            \
1806                 inp->inp_flags2 &= ~bit;                                \
1807 } while (0)
1808 #define OPTSET2(bit, val) do {                                          \
1809         INP_WLOCK(inp);                                                 \
1810         OPTSET2_N(bit, val);                                            \
1811         INP_WUNLOCK(inp);                                               \
1812 } while (0)
1813 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1814 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1815 do {                                                                    \
1816         INP_WLOCK(inp);                                                 \
1817         if (OPTBIT(IN6P_RFC2292)) {                                     \
1818                 error = EINVAL;                                         \
1819         } else {                                                        \
1820                 if (optval)                                             \
1821                         inp->inp_flags |= (bit);                        \
1822                 else                                                    \
1823                         inp->inp_flags &= ~(bit);                       \
1824         }                                                               \
1825         INP_WUNLOCK(inp);                                               \
1826 } while (/*CONSTCOND*/ 0)
1827
1828                                 case IPV6_RECVPKTINFO:
1829                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1830                                         break;
1831
1832                                 case IPV6_HOPLIMIT:
1833                                 {
1834                                         struct ip6_pktopts **optp;
1835
1836                                         /* cannot mix with RFC2292 */
1837                                         if (OPTBIT(IN6P_RFC2292)) {
1838                                                 error = EINVAL;
1839                                                 break;
1840                                         }
1841                                         INP_WLOCK(inp);
1842                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1843                                                 INP_WUNLOCK(inp);
1844                                                 return (ECONNRESET);
1845                                         }
1846                                         optp = &inp->in6p_outputopts;
1847                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1848                                             (u_char *)&optval, sizeof(optval),
1849                                             optp, (td != NULL) ? td->td_ucred :
1850                                             NULL, uproto);
1851                                         INP_WUNLOCK(inp);
1852                                         break;
1853                                 }
1854
1855                                 case IPV6_RECVHOPLIMIT:
1856                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1857                                         break;
1858
1859                                 case IPV6_RECVHOPOPTS:
1860                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1861                                         break;
1862
1863                                 case IPV6_RECVDSTOPTS:
1864                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1865                                         break;
1866
1867                                 case IPV6_RECVRTHDRDSTOPTS:
1868                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1869                                         break;
1870
1871                                 case IPV6_RECVRTHDR:
1872                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1873                                         break;
1874
1875                                 case IPV6_RECVPATHMTU:
1876                                         /*
1877                                          * We ignore this option for TCP
1878                                          * sockets.
1879                                          * (RFC3542 leaves this case
1880                                          * unspecified.)
1881                                          */
1882                                         if (uproto != IPPROTO_TCP)
1883                                                 OPTSET(IN6P_MTU);
1884                                         break;
1885
1886                                 case IPV6_RECVFLOWID:
1887                                         OPTSET2(INP_RECVFLOWID, optval);
1888                                         break;
1889
1890 #ifdef  RSS
1891                                 case IPV6_RECVRSSBUCKETID:
1892                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1893                                         break;
1894 #endif
1895
1896                                 case IPV6_V6ONLY:
1897                                         INP_WLOCK(inp);
1898                                         if (inp->inp_lport ||
1899                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1900                                                 /*
1901                                                  * The socket is already bound.
1902                                                  */
1903                                                 INP_WUNLOCK(inp);
1904                                                 error = EINVAL;
1905                                                 break;
1906                                         }
1907                                         if (optval) {
1908                                                 inp->inp_flags |= IN6P_IPV6_V6ONLY;
1909                                                 inp->inp_vflag &= ~INP_IPV4;
1910                                         } else {
1911                                                 inp->inp_flags &= ~IN6P_IPV6_V6ONLY;
1912                                                 inp->inp_vflag |= INP_IPV4;
1913                                         }
1914                                         INP_WUNLOCK(inp);
1915                                         break;
1916                                 case IPV6_RECVTCLASS:
1917                                         /* cannot mix with RFC2292 XXX */
1918                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1919                                         break;
1920                                 case IPV6_AUTOFLOWLABEL:
1921                                         OPTSET(IN6P_AUTOFLOWLABEL);
1922                                         break;
1923
1924                                 case IPV6_ORIGDSTADDR:
1925                                         OPTSET2(INP_ORIGDSTADDR, optval);
1926                                         break;
1927                                 case IPV6_BINDANY:
1928                                         OPTSET(INP_BINDANY);
1929                                         break;
1930
1931                                 case IPV6_BINDMULTI:
1932                                         OPTSET2(INP_BINDMULTI, optval);
1933                                         break;
1934 #ifdef  RSS
1935                                 case IPV6_RSS_LISTEN_BUCKET:
1936                                         if ((optval >= 0) &&
1937                                             (optval < rss_getnumbuckets())) {
1938                                                 INP_WLOCK(inp);
1939                                                 inp->inp_rss_listen_bucket = optval;
1940                                                 OPTSET2_N(INP_RSS_BUCKET_SET, 1);
1941                                                 INP_WUNLOCK(inp);
1942                                         } else {
1943                                                 error = EINVAL;
1944                                         }
1945                                         break;
1946 #endif
1947                                 }
1948                                 break;
1949
1950                         case IPV6_TCLASS:
1951                         case IPV6_DONTFRAG:
1952                         case IPV6_USE_MIN_MTU:
1953                         case IPV6_PREFER_TEMPADDR:
1954                                 if (optlen != sizeof(optval)) {
1955                                         error = EINVAL;
1956                                         break;
1957                                 }
1958                                 error = sooptcopyin(sopt, &optval,
1959                                         sizeof optval, sizeof optval);
1960                                 if (error)
1961                                         break;
1962                                 {
1963                                         struct ip6_pktopts **optp;
1964                                         INP_WLOCK(inp);
1965                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1966                                                 INP_WUNLOCK(inp);
1967                                                 return (ECONNRESET);
1968                                         }
1969                                         optp = &inp->in6p_outputopts;
1970                                         error = ip6_pcbopt(optname,
1971                                             (u_char *)&optval, sizeof(optval),
1972                                             optp, (td != NULL) ? td->td_ucred :
1973                                             NULL, uproto);
1974                                         INP_WUNLOCK(inp);
1975                                         break;
1976                                 }
1977
1978                         case IPV6_2292PKTINFO:
1979                         case IPV6_2292HOPLIMIT:
1980                         case IPV6_2292HOPOPTS:
1981                         case IPV6_2292DSTOPTS:
1982                         case IPV6_2292RTHDR:
1983                                 /* RFC 2292 */
1984                                 if (optlen != sizeof(int)) {
1985                                         error = EINVAL;
1986                                         break;
1987                                 }
1988                                 error = sooptcopyin(sopt, &optval,
1989                                         sizeof optval, sizeof optval);
1990                                 if (error)
1991                                         break;
1992                                 switch (optname) {
1993                                 case IPV6_2292PKTINFO:
1994                                         OPTSET2292(IN6P_PKTINFO);
1995                                         break;
1996                                 case IPV6_2292HOPLIMIT:
1997                                         OPTSET2292(IN6P_HOPLIMIT);
1998                                         break;
1999                                 case IPV6_2292HOPOPTS:
2000                                         /*
2001                                          * Check super-user privilege.
2002                                          * See comments for IPV6_RECVHOPOPTS.
2003                                          */
2004                                         if (td != NULL) {
2005                                                 error = priv_check(td,
2006                                                     PRIV_NETINET_SETHDROPTS);
2007                                                 if (error)
2008                                                         return (error);
2009                                         }
2010                                         OPTSET2292(IN6P_HOPOPTS);
2011                                         break;
2012                                 case IPV6_2292DSTOPTS:
2013                                         if (td != NULL) {
2014                                                 error = priv_check(td,
2015                                                     PRIV_NETINET_SETHDROPTS);
2016                                                 if (error)
2017                                                         return (error);
2018                                         }
2019                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
2020                                         break;
2021                                 case IPV6_2292RTHDR:
2022                                         OPTSET2292(IN6P_RTHDR);
2023                                         break;
2024                                 }
2025                                 break;
2026                         case IPV6_PKTINFO:
2027                         case IPV6_HOPOPTS:
2028                         case IPV6_RTHDR:
2029                         case IPV6_DSTOPTS:
2030                         case IPV6_RTHDRDSTOPTS:
2031                         case IPV6_NEXTHOP:
2032                         {
2033                                 /* new advanced API (RFC3542) */
2034                                 u_char *optbuf;
2035                                 u_char optbuf_storage[MCLBYTES];
2036                                 int optlen;
2037                                 struct ip6_pktopts **optp;
2038
2039                                 /* cannot mix with RFC2292 */
2040                                 if (OPTBIT(IN6P_RFC2292)) {
2041                                         error = EINVAL;
2042                                         break;
2043                                 }
2044
2045                                 /*
2046                                  * We only ensure valsize is not too large
2047                                  * here.  Further validation will be done
2048                                  * later.
2049                                  */
2050                                 error = sooptcopyin(sopt, optbuf_storage,
2051                                     sizeof(optbuf_storage), 0);
2052                                 if (error)
2053                                         break;
2054                                 optlen = sopt->sopt_valsize;
2055                                 optbuf = optbuf_storage;
2056                                 INP_WLOCK(inp);
2057                                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
2058                                         INP_WUNLOCK(inp);
2059                                         return (ECONNRESET);
2060                                 }
2061                                 optp = &inp->in6p_outputopts;
2062                                 error = ip6_pcbopt(optname, optbuf, optlen,
2063                                     optp, (td != NULL) ? td->td_ucred : NULL,
2064                                     uproto);
2065                                 INP_WUNLOCK(inp);
2066                                 break;
2067                         }
2068 #undef OPTSET
2069
2070                         case IPV6_MULTICAST_IF:
2071                         case IPV6_MULTICAST_HOPS:
2072                         case IPV6_MULTICAST_LOOP:
2073                         case IPV6_JOIN_GROUP:
2074                         case IPV6_LEAVE_GROUP:
2075                         case IPV6_MSFILTER:
2076                         case MCAST_BLOCK_SOURCE:
2077                         case MCAST_UNBLOCK_SOURCE:
2078                         case MCAST_JOIN_GROUP:
2079                         case MCAST_LEAVE_GROUP:
2080                         case MCAST_JOIN_SOURCE_GROUP:
2081                         case MCAST_LEAVE_SOURCE_GROUP:
2082                                 error = ip6_setmoptions(inp, sopt);
2083                                 break;
2084
2085                         case IPV6_PORTRANGE:
2086                                 error = sooptcopyin(sopt, &optval,
2087                                     sizeof optval, sizeof optval);
2088                                 if (error)
2089                                         break;
2090
2091                                 INP_WLOCK(inp);
2092                                 switch (optval) {
2093                                 case IPV6_PORTRANGE_DEFAULT:
2094                                         inp->inp_flags &= ~(INP_LOWPORT);
2095                                         inp->inp_flags &= ~(INP_HIGHPORT);
2096                                         break;
2097
2098                                 case IPV6_PORTRANGE_HIGH:
2099                                         inp->inp_flags &= ~(INP_LOWPORT);
2100                                         inp->inp_flags |= INP_HIGHPORT;
2101                                         break;
2102
2103                                 case IPV6_PORTRANGE_LOW:
2104                                         inp->inp_flags &= ~(INP_HIGHPORT);
2105                                         inp->inp_flags |= INP_LOWPORT;
2106                                         break;
2107
2108                                 default:
2109                                         error = EINVAL;
2110                                         break;
2111                                 }
2112                                 INP_WUNLOCK(inp);
2113                                 break;
2114
2115 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2116                         case IPV6_IPSEC_POLICY:
2117                                 if (IPSEC_ENABLED(ipv6)) {
2118                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2119                                         break;
2120                                 }
2121                                 /* FALLTHROUGH */
2122 #endif /* IPSEC */
2123
2124                         default:
2125                                 error = ENOPROTOOPT;
2126                                 break;
2127                         }
2128                         break;
2129
2130                 case SOPT_GET:
2131                         switch (optname) {
2132
2133                         case IPV6_2292PKTOPTIONS:
2134 #ifdef IPV6_PKTOPTIONS
2135                         case IPV6_PKTOPTIONS:
2136 #endif
2137                                 /*
2138                                  * RFC3542 (effectively) deprecated the
2139                                  * semantics of the 2292-style pktoptions.
2140                                  * Since it was not reliable in nature (i.e.,
2141                                  * applications had to expect the lack of some
2142                                  * information after all), it would make sense
2143                                  * to simplify this part by always returning
2144                                  * empty data.
2145                                  */
2146                                 sopt->sopt_valsize = 0;
2147                                 break;
2148
2149                         case IPV6_RECVHOPOPTS:
2150                         case IPV6_RECVDSTOPTS:
2151                         case IPV6_RECVRTHDRDSTOPTS:
2152                         case IPV6_UNICAST_HOPS:
2153                         case IPV6_RECVPKTINFO:
2154                         case IPV6_RECVHOPLIMIT:
2155                         case IPV6_RECVRTHDR:
2156                         case IPV6_RECVPATHMTU:
2157
2158                         case IPV6_V6ONLY:
2159                         case IPV6_PORTRANGE:
2160                         case IPV6_RECVTCLASS:
2161                         case IPV6_AUTOFLOWLABEL:
2162                         case IPV6_BINDANY:
2163                         case IPV6_FLOWID:
2164                         case IPV6_FLOWTYPE:
2165                         case IPV6_RECVFLOWID:
2166 #ifdef  RSS
2167                         case IPV6_RSSBUCKETID:
2168                         case IPV6_RECVRSSBUCKETID:
2169 #endif
2170                         case IPV6_BINDMULTI:
2171                                 switch (optname) {
2172
2173                                 case IPV6_RECVHOPOPTS:
2174                                         optval = OPTBIT(IN6P_HOPOPTS);
2175                                         break;
2176
2177                                 case IPV6_RECVDSTOPTS:
2178                                         optval = OPTBIT(IN6P_DSTOPTS);
2179                                         break;
2180
2181                                 case IPV6_RECVRTHDRDSTOPTS:
2182                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2183                                         break;
2184
2185                                 case IPV6_UNICAST_HOPS:
2186                                         optval = inp->in6p_hops;
2187                                         break;
2188
2189                                 case IPV6_RECVPKTINFO:
2190                                         optval = OPTBIT(IN6P_PKTINFO);
2191                                         break;
2192
2193                                 case IPV6_RECVHOPLIMIT:
2194                                         optval = OPTBIT(IN6P_HOPLIMIT);
2195                                         break;
2196
2197                                 case IPV6_RECVRTHDR:
2198                                         optval = OPTBIT(IN6P_RTHDR);
2199                                         break;
2200
2201                                 case IPV6_RECVPATHMTU:
2202                                         optval = OPTBIT(IN6P_MTU);
2203                                         break;
2204
2205                                 case IPV6_V6ONLY:
2206                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2207                                         break;
2208
2209                                 case IPV6_PORTRANGE:
2210                                     {
2211                                         int flags;
2212                                         flags = inp->inp_flags;
2213                                         if (flags & INP_HIGHPORT)
2214                                                 optval = IPV6_PORTRANGE_HIGH;
2215                                         else if (flags & INP_LOWPORT)
2216                                                 optval = IPV6_PORTRANGE_LOW;
2217                                         else
2218                                                 optval = 0;
2219                                         break;
2220                                     }
2221                                 case IPV6_RECVTCLASS:
2222                                         optval = OPTBIT(IN6P_TCLASS);
2223                                         break;
2224
2225                                 case IPV6_AUTOFLOWLABEL:
2226                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2227                                         break;
2228
2229                                 case IPV6_ORIGDSTADDR:
2230                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2231                                         break;
2232
2233                                 case IPV6_BINDANY:
2234                                         optval = OPTBIT(INP_BINDANY);
2235                                         break;
2236
2237                                 case IPV6_FLOWID:
2238                                         optval = inp->inp_flowid;
2239                                         break;
2240
2241                                 case IPV6_FLOWTYPE:
2242                                         optval = inp->inp_flowtype;
2243                                         break;
2244
2245                                 case IPV6_RECVFLOWID:
2246                                         optval = OPTBIT2(INP_RECVFLOWID);
2247                                         break;
2248 #ifdef  RSS
2249                                 case IPV6_RSSBUCKETID:
2250                                         retval =
2251                                             rss_hash2bucket(inp->inp_flowid,
2252                                             inp->inp_flowtype,
2253                                             &rss_bucket);
2254                                         if (retval == 0)
2255                                                 optval = rss_bucket;
2256                                         else
2257                                                 error = EINVAL;
2258                                         break;
2259
2260                                 case IPV6_RECVRSSBUCKETID:
2261                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2262                                         break;
2263 #endif
2264
2265                                 case IPV6_BINDMULTI:
2266                                         optval = OPTBIT2(INP_BINDMULTI);
2267                                         break;
2268
2269                                 }
2270                                 if (error)
2271                                         break;
2272                                 error = sooptcopyout(sopt, &optval,
2273                                         sizeof optval);
2274                                 break;
2275
2276                         case IPV6_PATHMTU:
2277                         {
2278                                 u_long pmtu = 0;
2279                                 struct ip6_mtuinfo mtuinfo;
2280                                 struct in6_addr addr;
2281
2282                                 if (!(so->so_state & SS_ISCONNECTED))
2283                                         return (ENOTCONN);
2284                                 /*
2285                                  * XXX: we dot not consider the case of source
2286                                  * routing, or optional information to specify
2287                                  * the outgoing interface.
2288                                  * Copy faddr out of inp to avoid holding lock
2289                                  * on inp during route lookup.
2290                                  */
2291                                 INP_RLOCK(inp);
2292                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2293                                 INP_RUNLOCK(inp);
2294                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2295                                     &addr, &pmtu);
2296                                 if (error)
2297                                         break;
2298                                 if (pmtu > IPV6_MAXPACKET)
2299                                         pmtu = IPV6_MAXPACKET;
2300
2301                                 bzero(&mtuinfo, sizeof(mtuinfo));
2302                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2303                                 optdata = (void *)&mtuinfo;
2304                                 optdatalen = sizeof(mtuinfo);
2305                                 error = sooptcopyout(sopt, optdata,
2306                                     optdatalen);
2307                                 break;
2308                         }
2309
2310                         case IPV6_2292PKTINFO:
2311                         case IPV6_2292HOPLIMIT:
2312                         case IPV6_2292HOPOPTS:
2313                         case IPV6_2292RTHDR:
2314                         case IPV6_2292DSTOPTS:
2315                                 switch (optname) {
2316                                 case IPV6_2292PKTINFO:
2317                                         optval = OPTBIT(IN6P_PKTINFO);
2318                                         break;
2319                                 case IPV6_2292HOPLIMIT:
2320                                         optval = OPTBIT(IN6P_HOPLIMIT);
2321                                         break;
2322                                 case IPV6_2292HOPOPTS:
2323                                         optval = OPTBIT(IN6P_HOPOPTS);
2324                                         break;
2325                                 case IPV6_2292RTHDR:
2326                                         optval = OPTBIT(IN6P_RTHDR);
2327                                         break;
2328                                 case IPV6_2292DSTOPTS:
2329                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2330                                         break;
2331                                 }
2332                                 error = sooptcopyout(sopt, &optval,
2333                                     sizeof optval);
2334                                 break;
2335                         case IPV6_PKTINFO:
2336                         case IPV6_HOPOPTS:
2337                         case IPV6_RTHDR:
2338                         case IPV6_DSTOPTS:
2339                         case IPV6_RTHDRDSTOPTS:
2340                         case IPV6_NEXTHOP:
2341                         case IPV6_TCLASS:
2342                         case IPV6_DONTFRAG:
2343                         case IPV6_USE_MIN_MTU:
2344                         case IPV6_PREFER_TEMPADDR:
2345                                 error = ip6_getpcbopt(inp, optname, sopt);
2346                                 break;
2347
2348                         case IPV6_MULTICAST_IF:
2349                         case IPV6_MULTICAST_HOPS:
2350                         case IPV6_MULTICAST_LOOP:
2351                         case IPV6_MSFILTER:
2352                                 error = ip6_getmoptions(inp, sopt);
2353                                 break;
2354
2355 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2356                         case IPV6_IPSEC_POLICY:
2357                                 if (IPSEC_ENABLED(ipv6)) {
2358                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2359                                         break;
2360                                 }
2361                                 /* FALLTHROUGH */
2362 #endif /* IPSEC */
2363                         default:
2364                                 error = ENOPROTOOPT;
2365                                 break;
2366                         }
2367                         break;
2368                 }
2369         }
2370         return (error);
2371 }
2372
2373 int
2374 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2375 {
2376         int error = 0, optval, optlen;
2377         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2378         struct inpcb *inp = sotoinpcb(so);
2379         int level, op, optname;
2380
2381         level = sopt->sopt_level;
2382         op = sopt->sopt_dir;
2383         optname = sopt->sopt_name;
2384         optlen = sopt->sopt_valsize;
2385
2386         if (level != IPPROTO_IPV6) {
2387                 return (EINVAL);
2388         }
2389
2390         switch (optname) {
2391         case IPV6_CHECKSUM:
2392                 /*
2393                  * For ICMPv6 sockets, no modification allowed for checksum
2394                  * offset, permit "no change" values to help existing apps.
2395                  *
2396                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2397                  * for an ICMPv6 socket will fail."
2398                  * The current behavior does not meet RFC3542.
2399                  */
2400                 switch (op) {
2401                 case SOPT_SET:
2402                         if (optlen != sizeof(int)) {
2403                                 error = EINVAL;
2404                                 break;
2405                         }
2406                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2407                                             sizeof(optval));
2408                         if (error)
2409                                 break;
2410                         if (optval < -1 || (optval % 2) != 0) {
2411                                 /*
2412                                  * The API assumes non-negative even offset
2413                                  * values or -1 as a special value.
2414                                  */
2415                                 error = EINVAL;
2416                         } else if (so->so_proto->pr_protocol ==
2417                             IPPROTO_ICMPV6) {
2418                                 if (optval != icmp6off)
2419                                         error = EINVAL;
2420                         } else
2421                                 inp->in6p_cksum = optval;
2422                         break;
2423
2424                 case SOPT_GET:
2425                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2426                                 optval = icmp6off;
2427                         else
2428                                 optval = inp->in6p_cksum;
2429
2430                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2431                         break;
2432
2433                 default:
2434                         error = EINVAL;
2435                         break;
2436                 }
2437                 break;
2438
2439         default:
2440                 error = ENOPROTOOPT;
2441                 break;
2442         }
2443
2444         return (error);
2445 }
2446
2447 /*
2448  * Set up IP6 options in pcb for insertion in output packets or
2449  * specifying behavior of outgoing packets.
2450  */
2451 static int
2452 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2453     struct socket *so, struct sockopt *sopt)
2454 {
2455         struct ip6_pktopts *opt = *pktopt;
2456         int error = 0;
2457         struct thread *td = sopt->sopt_td;
2458
2459         /* turn off any old options. */
2460         if (opt) {
2461 #ifdef DIAGNOSTIC
2462                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2463                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2464                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2465                         printf("ip6_pcbopts: all specified options are cleared.\n");
2466 #endif
2467                 ip6_clearpktopts(opt, -1);
2468         } else {
2469                 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT);
2470                 if (opt == NULL)
2471                         return (ENOMEM);
2472         }
2473         *pktopt = NULL;
2474
2475         if (!m || m->m_len == 0) {
2476                 /*
2477                  * Only turning off any previous options, regardless of
2478                  * whether the opt is just created or given.
2479                  */
2480                 free(opt, M_IP6OPT);
2481                 return (0);
2482         }
2483
2484         /*  set options specified by user. */
2485         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2486             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2487                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2488                 free(opt, M_IP6OPT);
2489                 return (error);
2490         }
2491         *pktopt = opt;
2492         return (0);
2493 }
2494
2495 /*
2496  * initialize ip6_pktopts.  beware that there are non-zero default values in
2497  * the struct.
2498  */
2499 void
2500 ip6_initpktopts(struct ip6_pktopts *opt)
2501 {
2502
2503         bzero(opt, sizeof(*opt));
2504         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2505         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2506         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2507         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2508 }
2509
2510 static int
2511 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2512     struct ucred *cred, int uproto)
2513 {
2514         struct ip6_pktopts *opt;
2515
2516         if (*pktopt == NULL) {
2517                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2518                     M_NOWAIT);
2519                 if (*pktopt == NULL)
2520                         return (ENOBUFS);
2521                 ip6_initpktopts(*pktopt);
2522         }
2523         opt = *pktopt;
2524
2525         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2526 }
2527
2528 #define GET_PKTOPT_VAR(field, lenexpr) do {                                     \
2529         if (pktopt && pktopt->field) {                                          \
2530                 INP_RUNLOCK(inp);                                               \
2531                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK);         \
2532                 malloc_optdata = true;                                          \
2533                 INP_RLOCK(inp);                                                 \
2534                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {            \
2535                         INP_RUNLOCK(inp);                                       \
2536                         free(optdata, M_TEMP);                                  \
2537                         return (ECONNRESET);                                    \
2538                 }                                                               \
2539                 pktopt = inp->in6p_outputopts;                                  \
2540                 if (pktopt && pktopt->field) {                                  \
2541                         optdatalen = min(lenexpr, sopt->sopt_valsize);          \
2542                         bcopy(&pktopt->field, optdata, optdatalen);             \
2543                 } else {                                                        \
2544                         free(optdata, M_TEMP);                                  \
2545                         optdata = NULL;                                         \
2546                         malloc_optdata = false;                                 \
2547                 }                                                               \
2548         }                                                                       \
2549 } while(0)
2550
2551 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                         \
2552         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2553
2554 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                        \
2555         pktopt->field->sa_len)
2556
2557 static int
2558 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2559 {
2560         void *optdata = NULL;
2561         bool malloc_optdata = false;
2562         int optdatalen = 0;
2563         int error = 0;
2564         struct in6_pktinfo null_pktinfo;
2565         int deftclass = 0, on;
2566         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2567         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2568         struct ip6_pktopts *pktopt;
2569
2570         INP_RLOCK(inp);
2571         pktopt = inp->in6p_outputopts;
2572
2573         switch (optname) {
2574         case IPV6_PKTINFO:
2575                 optdata = (void *)&null_pktinfo;
2576                 if (pktopt && pktopt->ip6po_pktinfo) {
2577                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2578                             sizeof(null_pktinfo));
2579                         in6_clearscope(&null_pktinfo.ipi6_addr);
2580                 } else {
2581                         /* XXX: we don't have to do this every time... */
2582                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2583                 }
2584                 optdatalen = sizeof(struct in6_pktinfo);
2585                 break;
2586         case IPV6_TCLASS:
2587                 if (pktopt && pktopt->ip6po_tclass >= 0)
2588                         deftclass = pktopt->ip6po_tclass;
2589                 optdata = (void *)&deftclass;
2590                 optdatalen = sizeof(int);
2591                 break;
2592         case IPV6_HOPOPTS:
2593                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2594                 break;
2595         case IPV6_RTHDR:
2596                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2597                 break;
2598         case IPV6_RTHDRDSTOPTS:
2599                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2600                 break;
2601         case IPV6_DSTOPTS:
2602                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2603                 break;
2604         case IPV6_NEXTHOP:
2605                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2606                 break;
2607         case IPV6_USE_MIN_MTU:
2608                 if (pktopt)
2609                         defminmtu = pktopt->ip6po_minmtu;
2610                 optdata = (void *)&defminmtu;
2611                 optdatalen = sizeof(int);
2612                 break;
2613         case IPV6_DONTFRAG:
2614                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2615                         on = 1;
2616                 else
2617                         on = 0;
2618                 optdata = (void *)&on;
2619                 optdatalen = sizeof(on);
2620                 break;
2621         case IPV6_PREFER_TEMPADDR:
2622                 if (pktopt)
2623                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2624                 optdata = (void *)&defpreftemp;
2625                 optdatalen = sizeof(int);
2626                 break;
2627         default:                /* should not happen */
2628 #ifdef DIAGNOSTIC
2629                 panic("ip6_getpcbopt: unexpected option\n");
2630 #endif
2631                 INP_RUNLOCK(inp);
2632                 return (ENOPROTOOPT);
2633         }
2634         INP_RUNLOCK(inp);
2635
2636         error = sooptcopyout(sopt, optdata, optdatalen);
2637         if (malloc_optdata)
2638                 free(optdata, M_TEMP);
2639
2640         return (error);
2641 }
2642
2643 void
2644 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2645 {
2646         if (pktopt == NULL)
2647                 return;
2648
2649         if (optname == -1 || optname == IPV6_PKTINFO) {
2650                 if (pktopt->ip6po_pktinfo)
2651                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2652                 pktopt->ip6po_pktinfo = NULL;
2653         }
2654         if (optname == -1 || optname == IPV6_HOPLIMIT)
2655                 pktopt->ip6po_hlim = -1;
2656         if (optname == -1 || optname == IPV6_TCLASS)
2657                 pktopt->ip6po_tclass = -1;
2658         if (optname == -1 || optname == IPV6_NEXTHOP) {
2659                 if (pktopt->ip6po_nextroute.ro_nh) {
2660                         NH_FREE(pktopt->ip6po_nextroute.ro_nh);
2661                         pktopt->ip6po_nextroute.ro_nh = NULL;
2662                 }
2663                 if (pktopt->ip6po_nexthop)
2664                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2665                 pktopt->ip6po_nexthop = NULL;
2666         }
2667         if (optname == -1 || optname == IPV6_HOPOPTS) {
2668                 if (pktopt->ip6po_hbh)
2669                         free(pktopt->ip6po_hbh, M_IP6OPT);
2670                 pktopt->ip6po_hbh = NULL;
2671         }
2672         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2673                 if (pktopt->ip6po_dest1)
2674                         free(pktopt->ip6po_dest1, M_IP6OPT);
2675                 pktopt->ip6po_dest1 = NULL;
2676         }
2677         if (optname == -1 || optname == IPV6_RTHDR) {
2678                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2679                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2680                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2681                 if (pktopt->ip6po_route.ro_nh) {
2682                         NH_FREE(pktopt->ip6po_route.ro_nh);
2683                         pktopt->ip6po_route.ro_nh = NULL;
2684                 }
2685         }
2686         if (optname == -1 || optname == IPV6_DSTOPTS) {
2687                 if (pktopt->ip6po_dest2)
2688                         free(pktopt->ip6po_dest2, M_IP6OPT);
2689                 pktopt->ip6po_dest2 = NULL;
2690         }
2691 }
2692
2693 #define PKTOPT_EXTHDRCPY(type) \
2694 do {\
2695         if (src->type) {\
2696                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2697                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2698                 if (dst->type == NULL)\
2699                         goto bad;\
2700                 bcopy(src->type, dst->type, hlen);\
2701         }\
2702 } while (/*CONSTCOND*/ 0)
2703
2704 static int
2705 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2706 {
2707         if (dst == NULL || src == NULL)  {
2708                 printf("ip6_clearpktopts: invalid argument\n");
2709                 return (EINVAL);
2710         }
2711
2712         dst->ip6po_hlim = src->ip6po_hlim;
2713         dst->ip6po_tclass = src->ip6po_tclass;
2714         dst->ip6po_flags = src->ip6po_flags;
2715         dst->ip6po_minmtu = src->ip6po_minmtu;
2716         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2717         if (src->ip6po_pktinfo) {
2718                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2719                     M_IP6OPT, canwait);
2720                 if (dst->ip6po_pktinfo == NULL)
2721                         goto bad;
2722                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2723         }
2724         if (src->ip6po_nexthop) {
2725                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2726                     M_IP6OPT, canwait);
2727                 if (dst->ip6po_nexthop == NULL)
2728                         goto bad;
2729                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2730                     src->ip6po_nexthop->sa_len);
2731         }
2732         PKTOPT_EXTHDRCPY(ip6po_hbh);
2733         PKTOPT_EXTHDRCPY(ip6po_dest1);
2734         PKTOPT_EXTHDRCPY(ip6po_dest2);
2735         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2736         return (0);
2737
2738   bad:
2739         ip6_clearpktopts(dst, -1);
2740         return (ENOBUFS);
2741 }
2742 #undef PKTOPT_EXTHDRCPY
2743
2744 struct ip6_pktopts *
2745 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2746 {
2747         int error;
2748         struct ip6_pktopts *dst;
2749
2750         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2751         if (dst == NULL)
2752                 return (NULL);
2753         ip6_initpktopts(dst);
2754
2755         if ((error = copypktopts(dst, src, canwait)) != 0) {
2756                 free(dst, M_IP6OPT);
2757                 return (NULL);
2758         }
2759
2760         return (dst);
2761 }
2762
2763 void
2764 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2765 {
2766         if (pktopt == NULL)
2767                 return;
2768
2769         ip6_clearpktopts(pktopt, -1);
2770
2771         free(pktopt, M_IP6OPT);
2772 }
2773
2774 /*
2775  * Set IPv6 outgoing packet options based on advanced API.
2776  */
2777 int
2778 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2779     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2780 {
2781         struct cmsghdr *cm = NULL;
2782
2783         if (control == NULL || opt == NULL)
2784                 return (EINVAL);
2785
2786         ip6_initpktopts(opt);
2787         if (stickyopt) {
2788                 int error;
2789
2790                 /*
2791                  * If stickyopt is provided, make a local copy of the options
2792                  * for this particular packet, then override them by ancillary
2793                  * objects.
2794                  * XXX: copypktopts() does not copy the cached route to a next
2795                  * hop (if any).  This is not very good in terms of efficiency,
2796                  * but we can allow this since this option should be rarely
2797                  * used.
2798                  */
2799                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2800                         return (error);
2801         }
2802
2803         /*
2804          * XXX: Currently, we assume all the optional information is stored
2805          * in a single mbuf.
2806          */
2807         if (control->m_next)
2808                 return (EINVAL);
2809
2810         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2811             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2812                 int error;
2813
2814                 if (control->m_len < CMSG_LEN(0))
2815                         return (EINVAL);
2816
2817                 cm = mtod(control, struct cmsghdr *);
2818                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2819                         return (EINVAL);
2820                 if (cm->cmsg_level != IPPROTO_IPV6)
2821                         continue;
2822
2823                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2824                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2825                 if (error)
2826                         return (error);
2827         }
2828
2829         return (0);
2830 }
2831
2832 /*
2833  * Set a particular packet option, as a sticky option or an ancillary data
2834  * item.  "len" can be 0 only when it's a sticky option.
2835  * We have 4 cases of combination of "sticky" and "cmsg":
2836  * "sticky=0, cmsg=0": impossible
2837  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2838  * "sticky=1, cmsg=0": RFC3542 socket option
2839  * "sticky=1, cmsg=1": RFC2292 socket option
2840  */
2841 static int
2842 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2843     struct ucred *cred, int sticky, int cmsg, int uproto)
2844 {
2845         int minmtupolicy, preftemp;
2846         int error;
2847
2848         if (!sticky && !cmsg) {
2849 #ifdef DIAGNOSTIC
2850                 printf("ip6_setpktopt: impossible case\n");
2851 #endif
2852                 return (EINVAL);
2853         }
2854
2855         /*
2856          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2857          * not be specified in the context of RFC3542.  Conversely,
2858          * RFC3542 types should not be specified in the context of RFC2292.
2859          */
2860         if (!cmsg) {
2861                 switch (optname) {
2862                 case IPV6_2292PKTINFO:
2863                 case IPV6_2292HOPLIMIT:
2864                 case IPV6_2292NEXTHOP:
2865                 case IPV6_2292HOPOPTS:
2866                 case IPV6_2292DSTOPTS:
2867                 case IPV6_2292RTHDR:
2868                 case IPV6_2292PKTOPTIONS:
2869                         return (ENOPROTOOPT);
2870                 }
2871         }
2872         if (sticky && cmsg) {
2873                 switch (optname) {
2874                 case IPV6_PKTINFO:
2875                 case IPV6_HOPLIMIT:
2876                 case IPV6_NEXTHOP:
2877                 case IPV6_HOPOPTS:
2878                 case IPV6_DSTOPTS:
2879                 case IPV6_RTHDRDSTOPTS:
2880                 case IPV6_RTHDR:
2881                 case IPV6_USE_MIN_MTU:
2882                 case IPV6_DONTFRAG:
2883                 case IPV6_TCLASS:
2884                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2885                         return (ENOPROTOOPT);
2886                 }
2887         }
2888
2889         switch (optname) {
2890         case IPV6_2292PKTINFO:
2891         case IPV6_PKTINFO:
2892         {
2893                 struct ifnet *ifp = NULL;
2894                 struct in6_pktinfo *pktinfo;
2895
2896                 if (len != sizeof(struct in6_pktinfo))
2897                         return (EINVAL);
2898
2899                 pktinfo = (struct in6_pktinfo *)buf;
2900
2901                 /*
2902                  * An application can clear any sticky IPV6_PKTINFO option by
2903                  * doing a "regular" setsockopt with ipi6_addr being
2904                  * in6addr_any and ipi6_ifindex being zero.
2905                  * [RFC 3542, Section 6]
2906                  */
2907                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2908                     pktinfo->ipi6_ifindex == 0 &&
2909                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2910                         ip6_clearpktopts(opt, optname);
2911                         break;
2912                 }
2913
2914                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2915                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2916                         return (EINVAL);
2917                 }
2918                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2919                         return (EINVAL);
2920                 /* validate the interface index if specified. */
2921                 if (pktinfo->ipi6_ifindex > V_if_index)
2922                          return (ENXIO);
2923                 if (pktinfo->ipi6_ifindex) {
2924                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2925                         if (ifp == NULL)
2926                                 return (ENXIO);
2927                 }
2928                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2929                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2930                         return (ENETDOWN);
2931
2932                 if (ifp != NULL &&
2933                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2934                         struct in6_ifaddr *ia;
2935
2936                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2937                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2938                         if (ia == NULL)
2939                                 return (EADDRNOTAVAIL);
2940                         ifa_free(&ia->ia_ifa);
2941                 }
2942                 /*
2943                  * We store the address anyway, and let in6_selectsrc()
2944                  * validate the specified address.  This is because ipi6_addr
2945                  * may not have enough information about its scope zone, and
2946                  * we may need additional information (such as outgoing
2947                  * interface or the scope zone of a destination address) to
2948                  * disambiguate the scope.
2949                  * XXX: the delay of the validation may confuse the
2950                  * application when it is used as a sticky option.
2951                  */
2952                 if (opt->ip6po_pktinfo == NULL) {
2953                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2954                             M_IP6OPT, M_NOWAIT);
2955                         if (opt->ip6po_pktinfo == NULL)
2956                                 return (ENOBUFS);
2957                 }
2958                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2959                 break;
2960         }
2961
2962         case IPV6_2292HOPLIMIT:
2963         case IPV6_HOPLIMIT:
2964         {
2965                 int *hlimp;
2966
2967                 /*
2968                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2969                  * to simplify the ordering among hoplimit options.
2970                  */
2971                 if (optname == IPV6_HOPLIMIT && sticky)
2972                         return (ENOPROTOOPT);
2973
2974                 if (len != sizeof(int))
2975                         return (EINVAL);
2976                 hlimp = (int *)buf;
2977                 if (*hlimp < -1 || *hlimp > 255)
2978                         return (EINVAL);
2979
2980                 opt->ip6po_hlim = *hlimp;
2981                 break;
2982         }
2983
2984         case IPV6_TCLASS:
2985         {
2986                 int tclass;
2987
2988                 if (len != sizeof(int))
2989                         return (EINVAL);
2990                 tclass = *(int *)buf;
2991                 if (tclass < -1 || tclass > 255)
2992                         return (EINVAL);
2993
2994                 opt->ip6po_tclass = tclass;
2995                 break;
2996         }
2997
2998         case IPV6_2292NEXTHOP:
2999         case IPV6_NEXTHOP:
3000                 if (cred != NULL) {
3001                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3002                         if (error)
3003                                 return (error);
3004                 }
3005
3006                 if (len == 0) { /* just remove the option */
3007                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
3008                         break;
3009                 }
3010
3011                 /* check if cmsg_len is large enough for sa_len */
3012                 if (len < sizeof(struct sockaddr) || len < *buf)
3013                         return (EINVAL);
3014
3015                 switch (((struct sockaddr *)buf)->sa_family) {
3016                 case AF_INET6:
3017                 {
3018                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
3019                         int error;
3020
3021                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
3022                                 return (EINVAL);
3023
3024                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
3025                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
3026                                 return (EINVAL);
3027                         }
3028                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
3029                             != 0) {
3030                                 return (error);
3031                         }
3032                         break;
3033                 }
3034                 case AF_LINK:   /* should eventually be supported */
3035                 default:
3036                         return (EAFNOSUPPORT);
3037                 }
3038
3039                 /* turn off the previous option, then set the new option. */
3040                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
3041                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
3042                 if (opt->ip6po_nexthop == NULL)
3043                         return (ENOBUFS);
3044                 bcopy(buf, opt->ip6po_nexthop, *buf);
3045                 break;
3046
3047         case IPV6_2292HOPOPTS:
3048         case IPV6_HOPOPTS:
3049         {
3050                 struct ip6_hbh *hbh;
3051                 int hbhlen;
3052
3053                 /*
3054                  * XXX: We don't allow a non-privileged user to set ANY HbH
3055                  * options, since per-option restriction has too much
3056                  * overhead.
3057                  */
3058                 if (cred != NULL) {
3059                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3060                         if (error)
3061                                 return (error);
3062                 }
3063
3064                 if (len == 0) {
3065                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
3066                         break;  /* just remove the option */
3067                 }
3068
3069                 /* message length validation */
3070                 if (len < sizeof(struct ip6_hbh))
3071                         return (EINVAL);
3072                 hbh = (struct ip6_hbh *)buf;
3073                 hbhlen = (hbh->ip6h_len + 1) << 3;
3074                 if (len != hbhlen)
3075                         return (EINVAL);
3076
3077                 /* turn off the previous option, then set the new option. */
3078                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
3079                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
3080                 if (opt->ip6po_hbh == NULL)
3081                         return (ENOBUFS);
3082                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
3083
3084                 break;
3085         }
3086
3087         case IPV6_2292DSTOPTS:
3088         case IPV6_DSTOPTS:
3089         case IPV6_RTHDRDSTOPTS:
3090         {
3091                 struct ip6_dest *dest, **newdest = NULL;
3092                 int destlen;
3093
3094                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
3095                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3096                         if (error)
3097                                 return (error);
3098                 }
3099
3100                 if (len == 0) {
3101                         ip6_clearpktopts(opt, optname);
3102                         break;  /* just remove the option */
3103                 }
3104
3105                 /* message length validation */
3106                 if (len < sizeof(struct ip6_dest))
3107                         return (EINVAL);
3108                 dest = (struct ip6_dest *)buf;
3109                 destlen = (dest->ip6d_len + 1) << 3;
3110                 if (len != destlen)
3111                         return (EINVAL);
3112
3113                 /*
3114                  * Determine the position that the destination options header
3115                  * should be inserted; before or after the routing header.
3116                  */
3117                 switch (optname) {
3118                 case IPV6_2292DSTOPTS:
3119                         /*
3120                          * The old advacned API is ambiguous on this point.
3121                          * Our approach is to determine the position based
3122                          * according to the existence of a routing header.
3123                          * Note, however, that this depends on the order of the
3124                          * extension headers in the ancillary data; the 1st
3125                          * part of the destination options header must appear
3126                          * before the routing header in the ancillary data,
3127                          * too.
3128                          * RFC3542 solved the ambiguity by introducing
3129                          * separate ancillary data or option types.
3130                          */
3131                         if (opt->ip6po_rthdr == NULL)
3132                                 newdest = &opt->ip6po_dest1;
3133                         else
3134                                 newdest = &opt->ip6po_dest2;
3135                         break;
3136                 case IPV6_RTHDRDSTOPTS:
3137                         newdest = &opt->ip6po_dest1;
3138                         break;
3139                 case IPV6_DSTOPTS:
3140                         newdest = &opt->ip6po_dest2;
3141                         break;
3142                 }
3143
3144                 /* turn off the previous option, then set the new option. */
3145                 ip6_clearpktopts(opt, optname);
3146                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3147                 if (*newdest == NULL)
3148                         return (ENOBUFS);
3149                 bcopy(dest, *newdest, destlen);
3150
3151                 break;
3152         }
3153
3154         case IPV6_2292RTHDR:
3155         case IPV6_RTHDR:
3156         {
3157                 struct ip6_rthdr *rth;
3158                 int rthlen;
3159
3160                 if (len == 0) {
3161                         ip6_clearpktopts(opt, IPV6_RTHDR);
3162                         break;  /* just remove the option */
3163                 }
3164
3165                 /* message length validation */
3166                 if (len < sizeof(struct ip6_rthdr))
3167                         return (EINVAL);
3168                 rth = (struct ip6_rthdr *)buf;
3169                 rthlen = (rth->ip6r_len + 1) << 3;
3170                 if (len != rthlen)
3171                         return (EINVAL);
3172
3173                 switch (rth->ip6r_type) {
3174                 case IPV6_RTHDR_TYPE_0:
3175                         if (rth->ip6r_len == 0) /* must contain one addr */
3176                                 return (EINVAL);
3177                         if (rth->ip6r_len % 2) /* length must be even */
3178                                 return (EINVAL);
3179                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3180                                 return (EINVAL);
3181                         break;
3182                 default:
3183                         return (EINVAL);        /* not supported */
3184                 }
3185
3186                 /* turn off the previous option */
3187                 ip6_clearpktopts(opt, IPV6_RTHDR);
3188                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3189                 if (opt->ip6po_rthdr == NULL)
3190                         return (ENOBUFS);
3191                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3192
3193                 break;
3194         }
3195
3196         case IPV6_USE_MIN_MTU:
3197                 if (len != sizeof(int))
3198                         return (EINVAL);
3199                 minmtupolicy = *(int *)buf;
3200                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3201                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3202                     minmtupolicy != IP6PO_MINMTU_ALL) {
3203                         return (EINVAL);
3204                 }
3205                 opt->ip6po_minmtu = minmtupolicy;
3206                 break;
3207
3208         case IPV6_DONTFRAG:
3209                 if (len != sizeof(int))
3210                         return (EINVAL);
3211
3212                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3213                         /*
3214                          * we ignore this option for TCP sockets.
3215                          * (RFC3542 leaves this case unspecified.)
3216                          */
3217                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3218                 } else
3219                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3220                 break;
3221
3222         case IPV6_PREFER_TEMPADDR:
3223                 if (len != sizeof(int))
3224                         return (EINVAL);
3225                 preftemp = *(int *)buf;
3226                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3227                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3228                     preftemp != IP6PO_TEMPADDR_PREFER) {
3229                         return (EINVAL);
3230                 }
3231                 opt->ip6po_prefer_tempaddr = preftemp;
3232                 break;
3233
3234         default:
3235                 return (ENOPROTOOPT);
3236         } /* end of switch */
3237
3238         return (0);
3239 }
3240
3241 /*
3242  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3243  * packet to the input queue of a specified interface.  Note that this
3244  * calls the output routine of the loopback "driver", but with an interface
3245  * pointer that might NOT be &loif -- easier than replicating that code here.
3246  */
3247 void
3248 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3249 {
3250         struct mbuf *copym;
3251         struct ip6_hdr *ip6;
3252
3253         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3254         if (copym == NULL)
3255                 return;
3256
3257         /*
3258          * Make sure to deep-copy IPv6 header portion in case the data
3259          * is in an mbuf cluster, so that we can safely override the IPv6
3260          * header portion later.
3261          */
3262         if (!M_WRITABLE(copym) ||
3263             copym->m_len < sizeof(struct ip6_hdr)) {
3264                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3265                 if (copym == NULL)
3266                         return;
3267         }
3268         ip6 = mtod(copym, struct ip6_hdr *);
3269         /*
3270          * clear embedded scope identifiers if necessary.
3271          * in6_clearscope will touch the addresses only when necessary.
3272          */
3273         in6_clearscope(&ip6->ip6_src);
3274         in6_clearscope(&ip6->ip6_dst);
3275         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3276                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3277                     CSUM_PSEUDO_HDR;
3278                 copym->m_pkthdr.csum_data = 0xffff;
3279         }
3280         if_simloop(ifp, copym, AF_INET6, 0);
3281 }
3282
3283 /*
3284  * Chop IPv6 header off from the payload.
3285  */
3286 static int
3287 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3288 {
3289         struct mbuf *mh;
3290         struct ip6_hdr *ip6;
3291
3292         ip6 = mtod(m, struct ip6_hdr *);
3293         if (m->m_len > sizeof(*ip6)) {
3294                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3295                 if (mh == NULL) {
3296                         m_freem(m);
3297                         return ENOBUFS;
3298                 }
3299                 m_move_pkthdr(mh, m);
3300                 M_ALIGN(mh, sizeof(*ip6));
3301                 m->m_len -= sizeof(*ip6);
3302                 m->m_data += sizeof(*ip6);
3303                 mh->m_next = m;
3304                 m = mh;
3305                 m->m_len = sizeof(*ip6);
3306                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3307         }
3308         exthdrs->ip6e_ip6 = m;
3309         return 0;
3310 }
3311
3312 /*
3313  * Compute IPv6 extension header length.
3314  */
3315 int
3316 ip6_optlen(struct inpcb *inp)
3317 {
3318         int len;
3319
3320         if (!inp->in6p_outputopts)
3321                 return 0;
3322
3323         len = 0;
3324 #define elen(x) \
3325     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3326
3327         len += elen(inp->in6p_outputopts->ip6po_hbh);
3328         if (inp->in6p_outputopts->ip6po_rthdr)
3329                 /* dest1 is valid with rthdr only */
3330                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3331         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3332         len += elen(inp->in6p_outputopts->ip6po_dest2);
3333         return len;
3334 #undef elen
3335 }