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/pfil.h>
  99 #include <net/rss_config.h>
 100 #include <net/vnet.h>
 101
 102 #include <netinet/in.h>
 103 #include <netinet/in_var.h>
 104 #include <netinet/ip_var.h>
 105 #include <netinet6/in6_fib.h>
 106 #include <netinet6/in6_var.h>
 107 #include <netinet/ip6.h>
 108 #include <netinet/icmp6.h>
 109 #include <netinet6/ip6_var.h>
 110 #include <netinet/in_pcb.h>
 111 #include <netinet/tcp_var.h>
 112 #include <netinet6/nd6.h>
 113 #include <netinet6/in6_rss.h>
 114
 115 #include <netipsec/ipsec_support.h>
 116 #ifdef SCTP
 117 #include <netinet/sctp.h>
 118 #include <netinet/sctp_crc32.h>
 119 #endif
 120
 121 #include <netinet6/ip6protosw.h>
 122 #include <netinet6/scope6_var.h>
 123
 124 extern int in6_mcast_loop;
 125
 126 struct ip6_exthdrs {
 127         struct mbuf *ip6e_ip6;
 128         struct mbuf *ip6e_hbh;
 129         struct mbuf *ip6e_dest1;
 130         struct mbuf *ip6e_rthdr;
 131         struct mbuf *ip6e_dest2;
 132 };
 133
 134 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 135
 136 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 137                            struct ucred *, int);
 138 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 139         struct socket *, struct sockopt *);
 140 static int ip6_getpcbopt(struct inpcb *, int, struct sockopt *);
 141 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 142         struct ucred *, int, int, int);
 143
 144 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 145 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 146         struct ip6_frag **);
 147 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 148 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 149 static int ip6_getpmtu(struct route_in6 *, int,
 150         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int,
 151         u_int);
 152 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 153         u_long *, int *, u_int);
 154 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 155 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 156
 157
 158 /*
 159  * Make an extension header from option data.  hp is the source, and
 160  * mp is the destination.
 161  */
 162 #define MAKE_EXTHDR(hp, mp)                                             \
 163     do {                                                                \
 164         if (hp) {                                                       \
 165                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 166                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 167                     ((eh)->ip6e_len + 1) << 3);                         \
 168                 if (error)                                              \
 169                         goto freehdrs;                                  \
 170         }                                                               \
 171     } while (/*CONSTCOND*/ 0)
 172
 173 /*
 174  * Form a chain of extension headers.
 175  * m is the extension header mbuf
 176  * mp is the previous mbuf in the chain
 177  * p is the next header
 178  * i is the type of option.
 179  */
 180 #define MAKE_CHAIN(m, mp, p, i)\
 181     do {\
 182         if (m) {\
 183                 if (!hdrsplit) \
 184                         panic("assumption failed: hdr not split"); \
 185                 *mtod((m), u_char *) = *(p);\
 186                 *(p) = (i);\
 187                 p = mtod((m), u_char *);\
 188                 (m)->m_next = (mp)->m_next;\
 189                 (mp)->m_next = (m);\
 190                 (mp) = (m);\
 191         }\
 192     } while (/*CONSTCOND*/ 0)
 193
 194 void
 195 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 196 {
 197         u_short csum;
 198
 199         csum = in_cksum_skip(m, offset + plen, offset);
 200         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 201                 csum = 0xffff;
 202         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 203
 204         if (offset + sizeof(csum) > m->m_len)
 205                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
 206         else
 207                 *(u_short *)mtodo(m, offset) = csum;
 208 }
 209
 210 int
 211 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 212     int fraglen , uint32_t id)
 213 {
 214         struct mbuf *m, **mnext, *m_frgpart;
 215         struct ip6_hdr *ip6, *mhip6;
 216         struct ip6_frag *ip6f;
 217         int off;
 218         int error;
 219         int tlen = m0->m_pkthdr.len;
 220
 221         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 222
 223         m = m0;
 224         ip6 = mtod(m, struct ip6_hdr *);
 225         mnext = &m->m_nextpkt;
 226
 227         for (off = hlen; off < tlen; off += fraglen) {
 228                 m = m_gethdr(M_NOWAIT, MT_DATA);
 229                 if (!m) {
 230                         IP6STAT_INC(ip6s_odropped);
 231                         return (ENOBUFS);
 232                 }
 233
 234                 /*
 235                  * Make sure the complete packet header gets copied
 236                  * from the originating mbuf to the newly created
 237                  * mbuf. This also ensures that existing firewall
 238                  * classification(s), VLAN tags and so on get copied
 239                  * to the resulting fragmented packet(s):
 240                  */
 241                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 242                         m_free(m);
 243                         IP6STAT_INC(ip6s_odropped);
 244                         return (ENOBUFS);
 245                 }
 246
 247                 *mnext = m;
 248                 mnext = &m->m_nextpkt;
 249                 m->m_data += max_linkhdr;
 250                 mhip6 = mtod(m, struct ip6_hdr *);
 251                 *mhip6 = *ip6;
 252                 m->m_len = sizeof(*mhip6);
 253                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 254                 if (error) {
 255                         IP6STAT_INC(ip6s_odropped);
 256                         return (error);
 257                 }
 258                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 259                 if (off + fraglen >= tlen)
 260                         fraglen = tlen - off;
 261                 else
 262                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 263                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 264                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 265                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 266                         IP6STAT_INC(ip6s_odropped);
 267                         return (ENOBUFS);
 268                 }
 269                 m_cat(m, m_frgpart);
 270                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 271                 ip6f->ip6f_reserved = 0;
 272                 ip6f->ip6f_ident = id;
 273                 ip6f->ip6f_nxt = nextproto;
 274                 IP6STAT_INC(ip6s_ofragments);
 275                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 276         }
 277
 278         return (0);
 279 }
 280
 281 static int
 282 ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp,
 283     struct mbuf *m, struct sockaddr_in6 *dst, struct route_in6 *ro)
 284 {
 285 #ifdef KERN_TLS
 286         struct ktls_session *tls = NULL;
 287 #endif
 288         struct m_snd_tag *mst;
 289         int error;
 290
 291         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 292         mst = NULL;
 293
 294 #ifdef KERN_TLS
 295         /*
 296          * If this is an unencrypted TLS record, save a reference to
 297          * the record.  This local reference is used to call
 298          * ktls_output_eagain after the mbuf has been freed (thus
 299          * dropping the mbuf's reference) in if_output.
 300          */
 301         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 302                 tls = ktls_hold(m->m_next->m_ext.ext_pgs->tls);
 303                 mst = tls->snd_tag;
 304
 305                 /*
 306                  * If a TLS session doesn't have a valid tag, it must
 307                  * have had an earlier ifp mismatch, so drop this
 308                  * packet.
 309                  */
 310                 if (mst == NULL) {
 311                         error = EAGAIN;
 312                         goto done;
 313                 }
 314         }
 315 #endif
 316 #ifdef RATELIMIT
 317         if (inp != NULL && mst == NULL) {
 318                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 319                     (inp->inp_snd_tag != NULL &&
 320                     inp->inp_snd_tag->ifp != ifp))
 321                         in_pcboutput_txrtlmt(inp, ifp, m);
 322
 323                 if (inp->inp_snd_tag != NULL)
 324                         mst = inp->inp_snd_tag;
 325         }
 326 #endif
 327         if (mst != NULL) {
 328                 KASSERT(m->m_pkthdr.rcvif == NULL,
 329                     ("trying to add a send tag to a forwarded packet"));
 330                 if (mst->ifp != ifp) {
 331                         error = EAGAIN;
 332                         goto done;
 333                 }
 334
 335                 /* stamp send tag on mbuf */
 336                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 337                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 338         }
 339
 340         error = nd6_output_ifp(ifp, origifp, m, dst, (struct route *)ro);
 341
 342 done:
 343         /* Check for route change invalidating send tags. */
 344 #ifdef KERN_TLS
 345         if (tls != NULL) {
 346                 if (error == EAGAIN)
 347                         error = ktls_output_eagain(inp, tls);
 348                 ktls_free(tls);
 349         }
 350 #endif
 351 #ifdef RATELIMIT
 352         if (error == EAGAIN)
 353                 in_pcboutput_eagain(inp);
 354 #endif
 355         return (error);
 356 }
 357
 358 /*
 359  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 360  * header (with pri, len, nxt, hlim, src, dst).
 361  * This function may modify ver and hlim only.
 362  * The mbuf chain containing the packet will be freed.
 363  * The mbuf opt, if present, will not be freed.
 364  * If route_in6 ro is present and has ro_rt initialized, route lookup would be
 365  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 366  * then result of route lookup is stored in ro->ro_rt.
 367  *
 368  * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
 369  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 370  * which is rt_mtu.
 371  *
 372  * ifpp - XXX: just for statistics
 373  */
 374 /*
 375  * XXX TODO: no flowid is assigned for outbound flows?
 376  */
 377 int
 378 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 379     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 380     struct ifnet **ifpp, struct inpcb *inp)
 381 {
 382         struct ip6_hdr *ip6;
 383         struct ifnet *ifp, *origifp;
 384         struct mbuf *m = m0;
 385         struct mbuf *mprev = NULL;
 386         int hlen, tlen, len;
 387         struct epoch_tracker et;
 388         struct route_in6 ip6route;
 389         struct rtentry *rt = NULL;
 390         struct sockaddr_in6 *dst, src_sa, dst_sa;
 391         struct in6_addr odst;
 392         int error = 0;
 393         struct in6_ifaddr *ia = NULL;
 394         u_long mtu;
 395         int alwaysfrag, dontfrag;
 396         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 397         struct ip6_exthdrs exthdrs;
 398         struct in6_addr src0, dst0;
 399         u_int32_t zone;
 400         struct route_in6 *ro_pmtu = NULL;
 401         int hdrsplit = 0;
 402         int sw_csum, tso;
 403         int needfiblookup;
 404         uint32_t fibnum;
 405         struct m_tag *fwd_tag = NULL;
 406         uint32_t id;
 407
 408         NET_EPOCH_ENTER(et);
 409
 410         if (inp != NULL) {
 411                 INP_LOCK_ASSERT(inp);
 412                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 413                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 414                         /* unconditionally set flowid */
 415                         m->m_pkthdr.flowid = inp->inp_flowid;
 416                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 417                 }
 418 #ifdef NUMA
 419                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 420 #endif
 421         }
 422
 423 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 424         /*
 425          * IPSec checking which handles several cases.
 426          * FAST IPSEC: We re-injected the packet.
 427          * XXX: need scope argument.
 428          */
 429         if (IPSEC_ENABLED(ipv6)) {
 430                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 431                         if (error == EINPROGRESS)
 432                                 error = 0;
 433                         goto done;
 434                 }
 435         }
 436 #endif /* IPSEC */
 437
 438         bzero(&exthdrs, sizeof(exthdrs));
 439         if (opt) {
 440                 /* Hop-by-Hop options header */
 441                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 442                 /* Destination options header(1st part) */
 443                 if (opt->ip6po_rthdr) {
 444                         /*
 445                          * Destination options header(1st part)
 446                          * This only makes sense with a routing header.
 447                          * See Section 9.2 of RFC 3542.
 448                          * Disabling this part just for MIP6 convenience is
 449                          * a bad idea.  We need to think carefully about a
 450                          * way to make the advanced API coexist with MIP6
 451                          * options, which might automatically be inserted in
 452                          * the kernel.
 453                          */
 454                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 455                 }
 456                 /* Routing header */
 457                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 458                 /* Destination options header(2nd part) */
 459                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 460         }
 461
 462         /*
 463          * Calculate the total length of the extension header chain.
 464          * Keep the length of the unfragmentable part for fragmentation.
 465          */
 466         optlen = 0;
 467         if (exthdrs.ip6e_hbh)
 468                 optlen += exthdrs.ip6e_hbh->m_len;
 469         if (exthdrs.ip6e_dest1)
 470                 optlen += exthdrs.ip6e_dest1->m_len;
 471         if (exthdrs.ip6e_rthdr)
 472                 optlen += exthdrs.ip6e_rthdr->m_len;
 473         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 474
 475         /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
 476         if (exthdrs.ip6e_dest2)
 477                 optlen += exthdrs.ip6e_dest2->m_len;
 478
 479         /*
 480          * If there is at least one extension header,
 481          * separate IP6 header from the payload.
 482          */
 483         if (optlen && !hdrsplit) {
 484                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 485                         m = NULL;
 486                         goto freehdrs;
 487                 }
 488                 m = exthdrs.ip6e_ip6;
 489                 hdrsplit++;
 490         }
 491
 492         ip6 = mtod(m, struct ip6_hdr *);
 493
 494         /* adjust mbuf packet header length */
 495         m->m_pkthdr.len += optlen;
 496         plen = m->m_pkthdr.len - sizeof(*ip6);
 497
 498         /* If this is a jumbo payload, insert a jumbo payload option. */
 499         if (plen > IPV6_MAXPACKET) {
 500                 if (!hdrsplit) {
 501                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 502                                 m = NULL;
 503                                 goto freehdrs;
 504                         }
 505                         m = exthdrs.ip6e_ip6;
 506                         hdrsplit++;
 507                 }
 508                 /* adjust pointer */
 509                 ip6 = mtod(m, struct ip6_hdr *);
 510                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 511                         goto freehdrs;
 512                 ip6->ip6_plen = 0;
 513         } else
 514                 ip6->ip6_plen = htons(plen);
 515
 516         /*
 517          * Concatenate headers and fill in next header fields.
 518          * Here we have, on "m"
 519          *      IPv6 payload
 520          * and we insert headers accordingly.  Finally, we should be getting:
 521          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 522          *
 523          * during the header composing process, "m" points to IPv6 header.
 524          * "mprev" points to an extension header prior to esp.
 525          */
 526         u_char *nexthdrp = &ip6->ip6_nxt;
 527         mprev = m;
 528
 529         /*
 530          * we treat dest2 specially.  this makes IPsec processing
 531          * much easier.  the goal here is to make mprev point the
 532          * mbuf prior to dest2.
 533          *
 534          * result: IPv6 dest2 payload
 535          * m and mprev will point to IPv6 header.
 536          */
 537         if (exthdrs.ip6e_dest2) {
 538                 if (!hdrsplit)
 539                         panic("assumption failed: hdr not split");
 540                 exthdrs.ip6e_dest2->m_next = m->m_next;
 541                 m->m_next = exthdrs.ip6e_dest2;
 542                 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 543                 ip6->ip6_nxt = IPPROTO_DSTOPTS;
 544         }
 545
 546         /*
 547          * result: IPv6 hbh dest1 rthdr dest2 payload
 548          * m will point to IPv6 header.  mprev will point to the
 549          * extension header prior to dest2 (rthdr in the above case).
 550          */
 551         MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 552         MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 553                    IPPROTO_DSTOPTS);
 554         MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 555                    IPPROTO_ROUTING);
 556
 557         /*
 558          * If there is a routing header, discard the packet.
 559          */
 560         if (exthdrs.ip6e_rthdr) {
 561                  error = EINVAL;
 562                  goto bad;
 563         }
 564
 565         /* Source address validation */
 566         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 567             (flags & IPV6_UNSPECSRC) == 0) {
 568                 error = EOPNOTSUPP;
 569                 IP6STAT_INC(ip6s_badscope);
 570                 goto bad;
 571         }
 572         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 573                 error = EOPNOTSUPP;
 574                 IP6STAT_INC(ip6s_badscope);
 575                 goto bad;
 576         }
 577
 578         IP6STAT_INC(ip6s_localout);
 579
 580         /*
 581          * Route packet.
 582          */
 583         if (ro == NULL) {
 584                 ro = &ip6route;
 585                 bzero((caddr_t)ro, sizeof(*ro));
 586         }
 587         ro_pmtu = ro;
 588         if (opt && opt->ip6po_rthdr)
 589                 ro = &opt->ip6po_route;
 590         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 591         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 592 again:
 593         /*
 594          * if specified, try to fill in the traffic class field.
 595          * do not override if a non-zero value is already set.
 596          * we check the diffserv field and the ecn field separately.
 597          */
 598         if (opt && opt->ip6po_tclass >= 0) {
 599                 int mask = 0;
 600
 601                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 602                         mask |= 0xfc;
 603                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 604                         mask |= 0x03;
 605                 if (mask != 0)
 606                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 607         }
 608
 609         /* fill in or override the hop limit field, if necessary. */
 610         if (opt && opt->ip6po_hlim != -1)
 611                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 612         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 613                 if (im6o != NULL)
 614                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 615                 else
 616                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 617         }
 618         /*
 619          * Validate route against routing table additions;
 620          * a better/more specific route might have been added.
 621          * Make sure address family is set in route.
 622          */
 623         if (inp) {
 624                 ro->ro_dst.sin6_family = AF_INET6;
 625                 RT_VALIDATE((struct route *)ro, &inp->inp_rt_cookie, fibnum);
 626         }
 627         if (ro->ro_rt && fwd_tag == NULL && (ro->ro_rt->rt_flags & RTF_UP) &&
 628             ro->ro_dst.sin6_family == AF_INET6 &&
 629             IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 630                 rt = ro->ro_rt;
 631                 ifp = ro->ro_rt->rt_ifp;
 632         } else {
 633                 if (ro->ro_lle)
 634                         LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 635                 ro->ro_lle = NULL;
 636                 if (fwd_tag == NULL) {
 637                         bzero(&dst_sa, sizeof(dst_sa));
 638                         dst_sa.sin6_family = AF_INET6;
 639                         dst_sa.sin6_len = sizeof(dst_sa);
 640                         dst_sa.sin6_addr = ip6->ip6_dst;
 641                 }
 642                 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
 643                     &rt, fibnum);
 644                 if (error != 0) {
 645                         if (ifp != NULL)
 646                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 647                         goto bad;
 648                 }
 649         }
 650         if (rt == NULL) {
 651                 /*
 652                  * If in6_selectroute() does not return a route entry,
 653                  * dst may not have been updated.
 654                  */
 655                 *dst = dst_sa;  /* XXX */
 656         }
 657
 658         /*
 659          * then rt (for unicast) and ifp must be non-NULL valid values.
 660          */
 661         if ((flags & IPV6_FORWARDING) == 0) {
 662                 /* XXX: the FORWARDING flag can be set for mrouting. */
 663                 in6_ifstat_inc(ifp, ifs6_out_request);
 664         }
 665         if (rt != NULL) {
 666                 ia = (struct in6_ifaddr *)(rt->rt_ifa);
 667                 counter_u64_add(rt->rt_pksent, 1);
 668         }
 669
 670         /* Setup data structures for scope ID checks. */
 671         src0 = ip6->ip6_src;
 672         bzero(&src_sa, sizeof(src_sa));
 673         src_sa.sin6_family = AF_INET6;
 674         src_sa.sin6_len = sizeof(src_sa);
 675         src_sa.sin6_addr = ip6->ip6_src;
 676
 677         dst0 = ip6->ip6_dst;
 678         /* re-initialize to be sure */
 679         bzero(&dst_sa, sizeof(dst_sa));
 680         dst_sa.sin6_family = AF_INET6;
 681         dst_sa.sin6_len = sizeof(dst_sa);
 682         dst_sa.sin6_addr = ip6->ip6_dst;
 683
 684         /* Check for valid scope ID. */
 685         if (in6_setscope(&src0, ifp, &zone) == 0 &&
 686             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 687             in6_setscope(&dst0, ifp, &zone) == 0 &&
 688             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 689                 /*
 690                  * The outgoing interface is in the zone of the source
 691                  * and destination addresses.
 692                  *
 693                  * Because the loopback interface cannot receive
 694                  * packets with a different scope ID than its own,
 695                  * there is a trick is to pretend the outgoing packet
 696                  * was received by the real network interface, by
 697                  * setting "origifp" different from "ifp". This is
 698                  * only allowed when "ifp" is a loopback network
 699                  * interface. Refer to code in nd6_output_ifp() for
 700                  * more details.
 701                  */
 702                 origifp = ifp;
 703
 704                 /*
 705                  * We should use ia_ifp to support the case of sending
 706                  * packets to an address of our own.
 707                  */
 708                 if (ia != NULL && ia->ia_ifp)
 709                         ifp = ia->ia_ifp;
 710
 711         } else if ((ifp->if_flags & IFF_LOOPBACK) == 0 ||
 712             sa6_recoverscope(&src_sa) != 0 ||
 713             sa6_recoverscope(&dst_sa) != 0 ||
 714             dst_sa.sin6_scope_id == 0 ||
 715             (src_sa.sin6_scope_id != 0 &&
 716             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 717             (origifp = ifnet_byindex(dst_sa.sin6_scope_id)) == NULL) {
 718                 /*
 719                  * If the destination network interface is not a
 720                  * loopback interface, or the destination network
 721                  * address has no scope ID, or the source address has
 722                  * a scope ID set which is different from the
 723                  * destination address one, or there is no network
 724                  * interface representing this scope ID, the address
 725                  * pair is considered invalid.
 726                  */
 727                 IP6STAT_INC(ip6s_badscope);
 728                 in6_ifstat_inc(ifp, ifs6_out_discard);
 729                 if (error == 0)
 730                         error = EHOSTUNREACH; /* XXX */
 731                 goto bad;
 732         }
 733
 734         /* All scope ID checks are successful. */
 735
 736         if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 737                 if (opt && opt->ip6po_nextroute.ro_rt) {
 738                         /*
 739                          * The nexthop is explicitly specified by the
 740                          * application.  We assume the next hop is an IPv6
 741                          * address.
 742                          */
 743                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 744                 }
 745                 else if ((rt->rt_flags & RTF_GATEWAY))
 746                         dst = (struct sockaddr_in6 *)rt->rt_gateway;
 747         }
 748
 749         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 750                 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
 751         } else {
 752                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 753                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 754                 /*
 755                  * Confirm that the outgoing interface supports multicast.
 756                  */
 757                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 758                         IP6STAT_INC(ip6s_noroute);
 759                         in6_ifstat_inc(ifp, ifs6_out_discard);
 760                         error = ENETUNREACH;
 761                         goto bad;
 762                 }
 763                 if ((im6o == NULL && in6_mcast_loop) ||
 764                     (im6o && im6o->im6o_multicast_loop)) {
 765                         /*
 766                          * Loop back multicast datagram if not expressly
 767                          * forbidden to do so, even if we have not joined
 768                          * the address; protocols will filter it later,
 769                          * thus deferring a hash lookup and lock acquisition
 770                          * at the expense of an m_copym().
 771                          */
 772                         ip6_mloopback(ifp, m);
 773                 } else {
 774                         /*
 775                          * If we are acting as a multicast router, perform
 776                          * multicast forwarding as if the packet had just
 777                          * arrived on the interface to which we are about
 778                          * to send.  The multicast forwarding function
 779                          * recursively calls this function, using the
 780                          * IPV6_FORWARDING flag to prevent infinite recursion.
 781                          *
 782                          * Multicasts that are looped back by ip6_mloopback(),
 783                          * above, will be forwarded by the ip6_input() routine,
 784                          * if necessary.
 785                          */
 786                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 787                                 /*
 788                                  * XXX: ip6_mforward expects that rcvif is NULL
 789                                  * when it is called from the originating path.
 790                                  * However, it may not always be the case.
 791                                  */
 792                                 m->m_pkthdr.rcvif = NULL;
 793                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 794                                         m_freem(m);
 795                                         goto done;
 796                                 }
 797                         }
 798                 }
 799                 /*
 800                  * Multicasts with a hoplimit of zero may be looped back,
 801                  * above, but must not be transmitted on a network.
 802                  * Also, multicasts addressed to the loopback interface
 803                  * are not sent -- the above call to ip6_mloopback() will
 804                  * loop back a copy if this host actually belongs to the
 805                  * destination group on the loopback interface.
 806                  */
 807                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 808                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 809                         m_freem(m);
 810                         goto done;
 811                 }
 812         }
 813
 814         /*
 815          * Fill the outgoing inteface to tell the upper layer
 816          * to increment per-interface statistics.
 817          */
 818         if (ifpp)
 819                 *ifpp = ifp;
 820
 821         /* Determine path MTU. */
 822         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 823                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 824                 goto bad;
 825
 826         /*
 827          * The caller of this function may specify to use the minimum MTU
 828          * in some cases.
 829          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 830          * setting.  The logic is a bit complicated; by default, unicast
 831          * packets will follow path MTU while multicast packets will be sent at
 832          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 833          * including unicast ones will be sent at the minimum MTU.  Multicast
 834          * packets will always be sent at the minimum MTU unless
 835          * IP6PO_MINMTU_DISABLE is explicitly specified.
 836          * See RFC 3542 for more details.
 837          */
 838         if (mtu > IPV6_MMTU) {
 839                 if ((flags & IPV6_MINMTU))
 840                         mtu = IPV6_MMTU;
 841                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 842                         mtu = IPV6_MMTU;
 843                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 844                          (opt == NULL ||
 845                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 846                         mtu = IPV6_MMTU;
 847                 }
 848         }
 849
 850         /*
 851          * clear embedded scope identifiers if necessary.
 852          * in6_clearscope will touch the addresses only when necessary.
 853          */
 854         in6_clearscope(&ip6->ip6_src);
 855         in6_clearscope(&ip6->ip6_dst);
 856
 857         /*
 858          * If the outgoing packet contains a hop-by-hop options header,
 859          * it must be examined and processed even by the source node.
 860          * (RFC 2460, section 4.)
 861          */
 862         if (exthdrs.ip6e_hbh) {
 863                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 864                 u_int32_t dummy; /* XXX unused */
 865                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 866
 867 #ifdef DIAGNOSTIC
 868                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 869                         panic("ip6e_hbh is not contiguous");
 870 #endif
 871                 /*
 872                  *  XXX: if we have to send an ICMPv6 error to the sender,
 873                  *       we need the M_LOOP flag since icmp6_error() expects
 874                  *       the IPv6 and the hop-by-hop options header are
 875                  *       contiguous unless the flag is set.
 876                  */
 877                 m->m_flags |= M_LOOP;
 878                 m->m_pkthdr.rcvif = ifp;
 879                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 880                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 881                     &dummy, &plen) < 0) {
 882                         /* m was already freed at this point */
 883                         error = EINVAL;/* better error? */
 884                         goto done;
 885                 }
 886                 m->m_flags &= ~M_LOOP; /* XXX */
 887                 m->m_pkthdr.rcvif = NULL;
 888         }
 889
 890         /* Jump over all PFIL processing if hooks are not active. */
 891         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
 892                 goto passout;
 893
 894         odst = ip6->ip6_dst;
 895         /* Run through list of hooks for output packets. */
 896         switch (pfil_run_hooks(V_inet6_pfil_head, &m, ifp, PFIL_OUT, inp)) {
 897         case PFIL_PASS:
 898                 ip6 = mtod(m, struct ip6_hdr *);
 899                 break;
 900         case PFIL_DROPPED:
 901                 error = EPERM;
 902                 /* FALLTHROUGH */
 903         case PFIL_CONSUMED:
 904                 goto done;
 905         }
 906
 907         needfiblookup = 0;
 908         /* See if destination IP address was changed by packet filter. */
 909         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
 910                 m->m_flags |= M_SKIP_FIREWALL;
 911                 /* If destination is now ourself drop to ip6_input(). */
 912                 if (in6_localip(&ip6->ip6_dst)) {
 913                         m->m_flags |= M_FASTFWD_OURS;
 914                         if (m->m_pkthdr.rcvif == NULL)
 915                                 m->m_pkthdr.rcvif = V_loif;
 916                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 917                                 m->m_pkthdr.csum_flags |=
 918                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 919                                 m->m_pkthdr.csum_data = 0xffff;
 920                         }
 921 #ifdef SCTP
 922                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 923                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 924 #endif
 925                         error = netisr_queue(NETISR_IPV6, m);
 926                         goto done;
 927                 } else {
 928                         RO_INVALIDATE_CACHE(ro);
 929                         needfiblookup = 1; /* Redo the routing table lookup. */
 930                 }
 931         }
 932         /* See if fib was changed by packet filter. */
 933         if (fibnum != M_GETFIB(m)) {
 934                 m->m_flags |= M_SKIP_FIREWALL;
 935                 fibnum = M_GETFIB(m);
 936                 RO_INVALIDATE_CACHE(ro);
 937                 needfiblookup = 1;
 938         }
 939         if (needfiblookup)
 940                 goto again;
 941
 942         /* See if local, if yes, send it to netisr. */
 943         if (m->m_flags & M_FASTFWD_OURS) {
 944                 if (m->m_pkthdr.rcvif == NULL)
 945                         m->m_pkthdr.rcvif = V_loif;
 946                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 947                         m->m_pkthdr.csum_flags |=
 948                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 949                         m->m_pkthdr.csum_data = 0xffff;
 950                 }
 951 #ifdef SCTP
 952                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 953                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 954 #endif
 955                 error = netisr_queue(NETISR_IPV6, m);
 956                 goto done;
 957         }
 958         /* Or forward to some other address? */
 959         if ((m->m_flags & M_IP6_NEXTHOP) &&
 960             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 961                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 962                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
 963                 m->m_flags |= M_SKIP_FIREWALL;
 964                 m->m_flags &= ~M_IP6_NEXTHOP;
 965                 m_tag_delete(m, fwd_tag);
 966                 goto again;
 967         }
 968
 969 passout:
 970         /*
 971          * Send the packet to the outgoing interface.
 972          * If necessary, do IPv6 fragmentation before sending.
 973          *
 974          * the logic here is rather complex:
 975          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 976          * 1-a: send as is if tlen <= path mtu
 977          * 1-b: fragment if tlen > path mtu
 978          *
 979          * 2: if user asks us not to fragment (dontfrag == 1)
 980          * 2-a: send as is if tlen <= interface mtu
 981          * 2-b: error if tlen > interface mtu
 982          *
 983          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 984          *      always fragment
 985          *
 986          * 4: if dontfrag == 1 && alwaysfrag == 1
 987          *      error, as we cannot handle this conflicting request
 988          */
 989         sw_csum = m->m_pkthdr.csum_flags;
 990         if (!hdrsplit) {
 991                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
 992                 sw_csum &= ~ifp->if_hwassist;
 993         } else
 994                 tso = 0;
 995         /*
 996          * If we added extension headers, we will not do TSO and calculate the
 997          * checksums ourselves for now.
 998          * XXX-BZ  Need a framework to know when the NIC can handle it, even
 999          * with ext. hdrs.
1000          */
1001         if (sw_csum & CSUM_DELAY_DATA_IPV6) {
1002                 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
1003                 m = mb_unmapped_to_ext(m);
1004                 if (m == NULL) {
1005                         error = ENOBUFS;
1006                         IP6STAT_INC(ip6s_odropped);
1007                         goto bad;
1008                 }
1009                 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
1010         } else if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {
1011                 m = mb_unmapped_to_ext(m);
1012                 if (m == NULL) {
1013                         error = ENOBUFS;
1014                         IP6STAT_INC(ip6s_odropped);
1015                         goto bad;
1016                 }
1017         }
1018 #ifdef SCTP
1019         if (sw_csum & CSUM_SCTP_IPV6) {
1020                 sw_csum &= ~CSUM_SCTP_IPV6;
1021                 m = mb_unmapped_to_ext(m);
1022                 if (m == NULL) {
1023                         error = ENOBUFS;
1024                         IP6STAT_INC(ip6s_odropped);
1025                         goto bad;
1026                 }
1027                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
1028         }
1029 #endif
1030         m->m_pkthdr.csum_flags &= ifp->if_hwassist;
1031         tlen = m->m_pkthdr.len;
1032
1033         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1034                 dontfrag = 1;
1035         else
1036                 dontfrag = 0;
1037         if (dontfrag && alwaysfrag) {   /* case 4 */
1038                 /* conflicting request - can't transmit */
1039                 error = EMSGSIZE;
1040                 goto bad;
1041         }
1042         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* case 2-b */
1043                 /*
1044                  * Even if the DONTFRAG option is specified, we cannot send the
1045                  * packet when the data length is larger than the MTU of the
1046                  * outgoing interface.
1047                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1048                  * application wanted to know the MTU value. Also return an
1049                  * error code (this is not described in the API spec).
1050                  */
1051                 if (inp != NULL)
1052                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1053                 error = EMSGSIZE;
1054                 goto bad;
1055         }
1056
1057         /*
1058          * transmit packet without fragmentation
1059          */
1060         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
1061                 struct in6_ifaddr *ia6;
1062
1063                 ip6 = mtod(m, struct ip6_hdr *);
1064                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1065                 if (ia6) {
1066                         /* Record statistics for this interface address. */
1067                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1068                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1069                             m->m_pkthdr.len);
1070                         ifa_free(&ia6->ia_ifa);
1071                 }
1072                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro);
1073                 goto done;
1074         }
1075
1076         /*
1077          * try to fragment the packet.  case 1-b and 3
1078          */
1079         if (mtu < IPV6_MMTU) {
1080                 /* path MTU cannot be less than IPV6_MMTU */
1081                 error = EMSGSIZE;
1082                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1083                 goto bad;
1084         } else if (ip6->ip6_plen == 0) {
1085                 /* jumbo payload cannot be fragmented */
1086                 error = EMSGSIZE;
1087                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1088                 goto bad;
1089         } else {
1090                 u_char nextproto;
1091
1092                 /*
1093                  * Too large for the destination or interface;
1094                  * fragment if possible.
1095                  * Must be able to put at least 8 bytes per fragment.
1096                  */
1097                 hlen = unfragpartlen;
1098                 if (mtu > IPV6_MAXPACKET)
1099                         mtu = IPV6_MAXPACKET;
1100
1101                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
1102                 if (len < 8) {
1103                         error = EMSGSIZE;
1104                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1105                         goto bad;
1106                 }
1107
1108                 /*
1109                  * If the interface will not calculate checksums on
1110                  * fragmented packets, then do it here.
1111                  * XXX-BZ handle the hw offloading case.  Need flags.
1112                  */
1113                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1114                         m = mb_unmapped_to_ext(m);
1115                         if (m == NULL) {
1116                                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1117                                 error = ENOBUFS;
1118                                 goto bad;
1119                         }
1120                         in6_delayed_cksum(m, plen, hlen);
1121                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
1122                 }
1123 #ifdef SCTP
1124                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
1125                         m = mb_unmapped_to_ext(m);
1126                         if (m == NULL) {
1127                                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1128                                 error = ENOBUFS;
1129                                 goto bad;
1130                         }
1131                         sctp_delayed_cksum(m, hlen);
1132                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
1133                 }
1134 #endif
1135                 /*
1136                  * Change the next header field of the last header in the
1137                  * unfragmentable part.
1138                  */
1139                 if (exthdrs.ip6e_rthdr) {
1140                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1141                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1142                 } else if (exthdrs.ip6e_dest1) {
1143                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1144                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1145                 } else if (exthdrs.ip6e_hbh) {
1146                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1147                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1148                 } else {
1149                         nextproto = ip6->ip6_nxt;
1150                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1151                 }
1152
1153                 /*
1154                  * Loop through length of segment after first fragment,
1155                  * make new header and copy data of each part and link onto
1156                  * chain.
1157                  */
1158                 m0 = m;
1159                 id = htonl(ip6_randomid());
1160                 if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
1161                         goto sendorfree;
1162
1163                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1164         }
1165
1166         /*
1167          * Remove leading garbages.
1168          */
1169 sendorfree:
1170         m = m0->m_nextpkt;
1171         m0->m_nextpkt = 0;
1172         m_freem(m0);
1173         for (; m; m = m0) {
1174                 m0 = m->m_nextpkt;
1175                 m->m_nextpkt = 0;
1176                 if (error == 0) {
1177                         /* Record statistics for this interface address. */
1178                         if (ia) {
1179                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1180                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1181                                     m->m_pkthdr.len);
1182                         }
1183                         error = ip6_output_send(inp, ifp, origifp, m, dst, ro);
1184                 } else
1185                         m_freem(m);
1186         }
1187
1188         if (error == 0)
1189                 IP6STAT_INC(ip6s_fragmented);
1190
1191 done:
1192         NET_EPOCH_EXIT(et);
1193         if (ro == &ip6route)
1194                 RO_RTFREE(ro);
1195         return (error);
1196
1197 freehdrs:
1198         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1199         m_freem(exthdrs.ip6e_dest1);
1200         m_freem(exthdrs.ip6e_rthdr);
1201         m_freem(exthdrs.ip6e_dest2);
1202         /* FALLTHROUGH */
1203 bad:
1204         if (m)
1205                 m_freem(m);
1206         goto done;
1207 }
1208
1209 static int
1210 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1211 {
1212         struct mbuf *m;
1213
1214         if (hlen > MCLBYTES)
1215                 return (ENOBUFS); /* XXX */
1216
1217         if (hlen > MLEN)
1218                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1219         else
1220                 m = m_get(M_NOWAIT, MT_DATA);
1221         if (m == NULL)
1222                 return (ENOBUFS);
1223         m->m_len = hlen;
1224         if (hdr)
1225                 bcopy(hdr, mtod(m, caddr_t), hlen);
1226
1227         *mp = m;
1228         return (0);
1229 }
1230
1231 /*
1232  * Insert jumbo payload option.
1233  */
1234 static int
1235 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1236 {
1237         struct mbuf *mopt;
1238         u_char *optbuf;
1239         u_int32_t v;
1240
1241 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1242
1243         /*
1244          * If there is no hop-by-hop options header, allocate new one.
1245          * If there is one but it doesn't have enough space to store the
1246          * jumbo payload option, allocate a cluster to store the whole options.
1247          * Otherwise, use it to store the options.
1248          */
1249         if (exthdrs->ip6e_hbh == NULL) {
1250                 mopt = m_get(M_NOWAIT, MT_DATA);
1251                 if (mopt == NULL)
1252                         return (ENOBUFS);
1253                 mopt->m_len = JUMBOOPTLEN;
1254                 optbuf = mtod(mopt, u_char *);
1255                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1256                 exthdrs->ip6e_hbh = mopt;
1257         } else {
1258                 struct ip6_hbh *hbh;
1259
1260                 mopt = exthdrs->ip6e_hbh;
1261                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1262                         /*
1263                          * XXX assumption:
1264                          * - exthdrs->ip6e_hbh is not referenced from places
1265                          *   other than exthdrs.
1266                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1267                          */
1268                         int oldoptlen = mopt->m_len;
1269                         struct mbuf *n;
1270
1271                         /*
1272                          * XXX: give up if the whole (new) hbh header does
1273                          * not fit even in an mbuf cluster.
1274                          */
1275                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1276                                 return (ENOBUFS);
1277
1278                         /*
1279                          * As a consequence, we must always prepare a cluster
1280                          * at this point.
1281                          */
1282                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1283                         if (n == NULL)
1284                                 return (ENOBUFS);
1285                         n->m_len = oldoptlen + JUMBOOPTLEN;
1286                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1287                             oldoptlen);
1288                         optbuf = mtod(n, caddr_t) + oldoptlen;
1289                         m_freem(mopt);
1290                         mopt = exthdrs->ip6e_hbh = n;
1291                 } else {
1292                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1293                         mopt->m_len += JUMBOOPTLEN;
1294                 }
1295                 optbuf[0] = IP6OPT_PADN;
1296                 optbuf[1] = 1;
1297
1298                 /*
1299                  * Adjust the header length according to the pad and
1300                  * the jumbo payload option.
1301                  */
1302                 hbh = mtod(mopt, struct ip6_hbh *);
1303                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1304         }
1305
1306         /* fill in the option. */
1307         optbuf[2] = IP6OPT_JUMBO;
1308         optbuf[3] = 4;
1309         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1310         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1311
1312         /* finally, adjust the packet header length */
1313         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1314
1315         return (0);
1316 #undef JUMBOOPTLEN
1317 }
1318
1319 /*
1320  * Insert fragment header and copy unfragmentable header portions.
1321  */
1322 static int
1323 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1324     struct ip6_frag **frghdrp)
1325 {
1326         struct mbuf *n, *mlast;
1327
1328         if (hlen > sizeof(struct ip6_hdr)) {
1329                 n = m_copym(m0, sizeof(struct ip6_hdr),
1330                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1331                 if (n == NULL)
1332                         return (ENOBUFS);
1333                 m->m_next = n;
1334         } else
1335                 n = m;
1336
1337         /* Search for the last mbuf of unfragmentable part. */
1338         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1339                 ;
1340
1341         if (M_WRITABLE(mlast) &&
1342             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1343                 /* use the trailing space of the last mbuf for the fragment hdr */
1344                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1345                     mlast->m_len);
1346                 mlast->m_len += sizeof(struct ip6_frag);
1347                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1348         } else {
1349                 /* allocate a new mbuf for the fragment header */
1350                 struct mbuf *mfrg;
1351
1352                 mfrg = m_get(M_NOWAIT, MT_DATA);
1353                 if (mfrg == NULL)
1354                         return (ENOBUFS);
1355                 mfrg->m_len = sizeof(struct ip6_frag);
1356                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1357                 mlast->m_next = mfrg;
1358         }
1359
1360         return (0);
1361 }
1362
1363 /*
1364  * Calculates IPv6 path mtu for destination @dst.
1365  * Resulting MTU is stored in @mtup.
1366  *
1367  * Returns 0 on success.
1368  */
1369 static int
1370 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1371 {
1372         struct nhop6_extended nh6;
1373         struct in6_addr kdst;
1374         uint32_t scopeid;
1375         struct ifnet *ifp;
1376         u_long mtu;
1377         int error;
1378
1379         in6_splitscope(dst, &kdst, &scopeid);
1380         if (fib6_lookup_nh_ext(fibnum, &kdst, scopeid, NHR_REF, 0, &nh6) != 0)
1381                 return (EHOSTUNREACH);
1382
1383         ifp = nh6.nh_ifp;
1384         mtu = nh6.nh_mtu;
1385
1386         error = ip6_calcmtu(ifp, dst, mtu, mtup, NULL, 0);
1387         fib6_free_nh_ext(fibnum, &nh6);
1388
1389         return (error);
1390 }
1391
1392 /*
1393  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1394  * and cached data in @ro_pmtu.
1395  * MTU from (successful) route lookup is saved (along with dst)
1396  * inside @ro_pmtu to avoid subsequent route lookups after packet
1397  * filter processing.
1398  *
1399  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1400  * Returns 0 on success.
1401  */
1402 static int
1403 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1404     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1405     int *alwaysfragp, u_int fibnum, u_int proto)
1406 {
1407         struct nhop6_basic nh6;
1408         struct in6_addr kdst;
1409         uint32_t scopeid;
1410         struct sockaddr_in6 *sa6_dst;
1411         u_long mtu;
1412
1413         mtu = 0;
1414         if (do_lookup) {
1415
1416                 /*
1417                  * Here ro_pmtu has final destination address, while
1418                  * ro might represent immediate destination.
1419                  * Use ro_pmtu destination since mtu might differ.
1420                  */
1421                 sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1422                 if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1423                         ro_pmtu->ro_mtu = 0;
1424
1425                 if (ro_pmtu->ro_mtu == 0) {
1426                         bzero(sa6_dst, sizeof(*sa6_dst));
1427                         sa6_dst->sin6_family = AF_INET6;
1428                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1429                         sa6_dst->sin6_addr = *dst;
1430
1431                         in6_splitscope(dst, &kdst, &scopeid);
1432                         if (fib6_lookup_nh_basic(fibnum, &kdst, scopeid, 0, 0,
1433                             &nh6) == 0)
1434                                 ro_pmtu->ro_mtu = nh6.nh_mtu;
1435                 }
1436
1437                 mtu = ro_pmtu->ro_mtu;
1438         }
1439
1440         if (ro_pmtu->ro_rt)
1441                 mtu = ro_pmtu->ro_rt->rt_mtu;
1442
1443         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1444 }
1445
1446 /*
1447  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1448  * hostcache data for @dst.
1449  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1450  *
1451  * Returns 0 on success.
1452  */
1453 static int
1454 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1455     u_long *mtup, int *alwaysfragp, u_int proto)
1456 {
1457         u_long mtu = 0;
1458         int alwaysfrag = 0;
1459         int error = 0;
1460
1461         if (rt_mtu > 0) {
1462                 u_int32_t ifmtu;
1463                 struct in_conninfo inc;
1464
1465                 bzero(&inc, sizeof(inc));
1466                 inc.inc_flags |= INC_ISIPV6;
1467                 inc.inc6_faddr = *dst;
1468
1469                 ifmtu = IN6_LINKMTU(ifp);
1470
1471                 /* TCP is known to react to pmtu changes so skip hc */
1472                 if (proto != IPPROTO_TCP)
1473                         mtu = tcp_hc_getmtu(&inc);
1474
1475                 if (mtu)
1476                         mtu = min(mtu, rt_mtu);
1477                 else
1478                         mtu = rt_mtu;
1479                 if (mtu == 0)
1480                         mtu = ifmtu;
1481                 else if (mtu < IPV6_MMTU) {
1482                         /*
1483                          * RFC2460 section 5, last paragraph:
1484                          * if we record ICMPv6 too big message with
1485                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1486                          * or smaller, with framgent header attached.
1487                          * (fragment header is needed regardless from the
1488                          * packet size, for translators to identify packets)
1489                          */
1490                         alwaysfrag = 1;
1491                         mtu = IPV6_MMTU;
1492                 }
1493         } else if (ifp) {
1494                 mtu = IN6_LINKMTU(ifp);
1495         } else
1496                 error = EHOSTUNREACH; /* XXX */
1497
1498         *mtup = mtu;
1499         if (alwaysfragp)
1500                 *alwaysfragp = alwaysfrag;
1501         return (error);
1502 }
1503
1504 /*
1505  * IP6 socket option processing.
1506  */
1507 int
1508 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1509 {
1510         int optdatalen, uproto;
1511         void *optdata;
1512         struct inpcb *inp = sotoinpcb(so);
1513         int error, optval;
1514         int level, op, optname;
1515         int optlen;
1516         struct thread *td;
1517 #ifdef  RSS
1518         uint32_t rss_bucket;
1519         int retval;
1520 #endif
1521
1522 /*
1523  * Don't use more than a quarter of mbuf clusters.  N.B.:
1524  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1525  * on LP64 architectures, so cast to u_long to avoid undefined
1526  * behavior.  ILP32 architectures cannot have nmbclusters
1527  * large enough to overflow for other reasons.
1528  */
1529 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1530
1531         level = sopt->sopt_level;
1532         op = sopt->sopt_dir;
1533         optname = sopt->sopt_name;
1534         optlen = sopt->sopt_valsize;
1535         td = sopt->sopt_td;
1536         error = 0;
1537         optval = 0;
1538         uproto = (int)so->so_proto->pr_protocol;
1539
1540         if (level != IPPROTO_IPV6) {
1541                 error = EINVAL;
1542
1543                 if (sopt->sopt_level == SOL_SOCKET &&
1544                     sopt->sopt_dir == SOPT_SET) {
1545                         switch (sopt->sopt_name) {
1546                         case SO_REUSEADDR:
1547                                 INP_WLOCK(inp);
1548                                 if ((so->so_options & SO_REUSEADDR) != 0)
1549                                         inp->inp_flags2 |= INP_REUSEADDR;
1550                                 else
1551                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1552                                 INP_WUNLOCK(inp);
1553                                 error = 0;
1554                                 break;
1555                         case SO_REUSEPORT:
1556                                 INP_WLOCK(inp);
1557                                 if ((so->so_options & SO_REUSEPORT) != 0)
1558                                         inp->inp_flags2 |= INP_REUSEPORT;
1559                                 else
1560                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1561                                 INP_WUNLOCK(inp);
1562                                 error = 0;
1563                                 break;
1564                         case SO_REUSEPORT_LB:
1565                                 INP_WLOCK(inp);
1566                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1567                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1568                                 else
1569                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1570                                 INP_WUNLOCK(inp);
1571                                 error = 0;
1572                                 break;
1573                         case SO_SETFIB:
1574                                 INP_WLOCK(inp);
1575                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1576                                 INP_WUNLOCK(inp);
1577                                 error = 0;
1578                                 break;
1579                         case SO_MAX_PACING_RATE:
1580 #ifdef RATELIMIT
1581                                 INP_WLOCK(inp);
1582                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1583                                 INP_WUNLOCK(inp);
1584                                 error = 0;
1585 #else
1586                                 error = EOPNOTSUPP;
1587 #endif
1588                                 break;
1589                         default:
1590                                 break;
1591                         }
1592                 }
1593         } else {                /* level == IPPROTO_IPV6 */
1594                 switch (op) {
1595
1596                 case SOPT_SET:
1597                         switch (optname) {
1598                         case IPV6_2292PKTOPTIONS:
1599 #ifdef IPV6_PKTOPTIONS
1600                         case IPV6_PKTOPTIONS:
1601 #endif
1602                         {
1603                                 struct mbuf *m;
1604
1605                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1606                                         printf("ip6_ctloutput: mbuf limit hit\n");
1607                                         error = ENOBUFS;
1608                                         break;
1609                                 }
1610
1611                                 error = soopt_getm(sopt, &m); /* XXX */
1612                                 if (error != 0)
1613                                         break;
1614                                 error = soopt_mcopyin(sopt, m); /* XXX */
1615                                 if (error != 0)
1616                                         break;
1617                                 error = ip6_pcbopts(&inp->in6p_outputopts,
1618                                                     m, so, sopt);
1619                                 m_freem(m); /* XXX */
1620                                 break;
1621                         }
1622
1623                         /*
1624                          * Use of some Hop-by-Hop options or some
1625                          * Destination options, might require special
1626                          * privilege.  That is, normal applications
1627                          * (without special privilege) might be forbidden
1628                          * from setting certain options in outgoing packets,
1629                          * and might never see certain options in received
1630                          * packets. [RFC 2292 Section 6]
1631                          * KAME specific note:
1632                          *  KAME prevents non-privileged users from sending or
1633                          *  receiving ANY hbh/dst options in order to avoid
1634                          *  overhead of parsing options in the kernel.
1635                          */
1636                         case IPV6_RECVHOPOPTS:
1637                         case IPV6_RECVDSTOPTS:
1638                         case IPV6_RECVRTHDRDSTOPTS:
1639                                 if (td != NULL) {
1640                                         error = priv_check(td,
1641                                             PRIV_NETINET_SETHDROPTS);
1642                                         if (error)
1643                                                 break;
1644                                 }
1645                                 /* FALLTHROUGH */
1646                         case IPV6_UNICAST_HOPS:
1647                         case IPV6_HOPLIMIT:
1648
1649                         case IPV6_RECVPKTINFO:
1650                         case IPV6_RECVHOPLIMIT:
1651                         case IPV6_RECVRTHDR:
1652                         case IPV6_RECVPATHMTU:
1653                         case IPV6_RECVTCLASS:
1654                         case IPV6_RECVFLOWID:
1655 #ifdef  RSS
1656                         case IPV6_RECVRSSBUCKETID:
1657 #endif
1658                         case IPV6_V6ONLY:
1659                         case IPV6_AUTOFLOWLABEL:
1660                         case IPV6_ORIGDSTADDR:
1661                         case IPV6_BINDANY:
1662                         case IPV6_BINDMULTI:
1663 #ifdef  RSS
1664                         case IPV6_RSS_LISTEN_BUCKET:
1665 #endif
1666                                 if (optname == IPV6_BINDANY && td != NULL) {
1667                                         error = priv_check(td,
1668                                             PRIV_NETINET_BINDANY);
1669                                         if (error)
1670                                                 break;
1671                                 }
1672
1673                                 if (optlen != sizeof(int)) {
1674                                         error = EINVAL;
1675                                         break;
1676                                 }
1677                                 error = sooptcopyin(sopt, &optval,
1678                                         sizeof optval, sizeof optval);
1679                                 if (error)
1680                                         break;
1681                                 switch (optname) {
1682
1683                                 case IPV6_UNICAST_HOPS:
1684                                         if (optval < -1 || optval >= 256)
1685                                                 error = EINVAL;
1686                                         else {
1687                                                 /* -1 = kernel default */
1688                                                 inp->in6p_hops = optval;
1689                                                 if ((inp->inp_vflag &
1690                                                      INP_IPV4) != 0)
1691                                                         inp->inp_ip_ttl = optval;
1692                                         }
1693                                         break;
1694 #define OPTSET(bit) \
1695 do { \
1696         INP_WLOCK(inp); \
1697         if (optval) \
1698                 inp->inp_flags |= (bit); \
1699         else \
1700                 inp->inp_flags &= ~(bit); \
1701         INP_WUNLOCK(inp); \
1702 } while (/*CONSTCOND*/ 0)
1703 #define OPTSET2292(bit) \
1704 do { \
1705         INP_WLOCK(inp); \
1706         inp->inp_flags |= IN6P_RFC2292; \
1707         if (optval) \
1708                 inp->inp_flags |= (bit); \
1709         else \
1710                 inp->inp_flags &= ~(bit); \
1711         INP_WUNLOCK(inp); \
1712 } while (/*CONSTCOND*/ 0)
1713 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1714
1715 #define OPTSET2_N(bit, val) do {                                        \
1716         if (val)                                                        \
1717                 inp->inp_flags2 |= bit;                                 \
1718         else                                                            \
1719                 inp->inp_flags2 &= ~bit;                                \
1720 } while (0)
1721 #define OPTSET2(bit, val) do {                                          \
1722         INP_WLOCK(inp);                                                 \
1723         OPTSET2_N(bit, val);                                            \
1724         INP_WUNLOCK(inp);                                               \
1725 } while (0)
1726 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1727 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1728 do {                                                                    \
1729         INP_WLOCK(inp);                                                 \
1730         if (OPTBIT(IN6P_RFC2292)) {                                     \
1731                 error = EINVAL;                                         \
1732         } else {                                                        \
1733                 if (optval)                                             \
1734                         inp->inp_flags |= (bit);                        \
1735                 else                                                    \
1736                         inp->inp_flags &= ~(bit);                       \
1737         }                                                               \
1738         INP_WUNLOCK(inp);                                               \
1739 } while (/*CONSTCOND*/ 0)
1740
1741                                 case IPV6_RECVPKTINFO:
1742                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1743                                         break;
1744
1745                                 case IPV6_HOPLIMIT:
1746                                 {
1747                                         struct ip6_pktopts **optp;
1748
1749                                         /* cannot mix with RFC2292 */
1750                                         if (OPTBIT(IN6P_RFC2292)) {
1751                                                 error = EINVAL;
1752                                                 break;
1753                                         }
1754                                         INP_WLOCK(inp);
1755                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1756                                                 INP_WUNLOCK(inp);
1757                                                 return (ECONNRESET);
1758                                         }
1759                                         optp = &inp->in6p_outputopts;
1760                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1761                                             (u_char *)&optval, sizeof(optval),
1762                                             optp, (td != NULL) ? td->td_ucred :
1763                                             NULL, uproto);
1764                                         INP_WUNLOCK(inp);
1765                                         break;
1766                                 }
1767
1768                                 case IPV6_RECVHOPLIMIT:
1769                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1770                                         break;
1771
1772                                 case IPV6_RECVHOPOPTS:
1773                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1774                                         break;
1775
1776                                 case IPV6_RECVDSTOPTS:
1777                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1778                                         break;
1779
1780                                 case IPV6_RECVRTHDRDSTOPTS:
1781                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1782                                         break;
1783
1784                                 case IPV6_RECVRTHDR:
1785                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1786                                         break;
1787
1788                                 case IPV6_RECVPATHMTU:
1789                                         /*
1790                                          * We ignore this option for TCP
1791                                          * sockets.
1792                                          * (RFC3542 leaves this case
1793                                          * unspecified.)
1794                                          */
1795                                         if (uproto != IPPROTO_TCP)
1796                                                 OPTSET(IN6P_MTU);
1797                                         break;
1798
1799                                 case IPV6_RECVFLOWID:
1800                                         OPTSET2(INP_RECVFLOWID, optval);
1801                                         break;
1802
1803 #ifdef  RSS
1804                                 case IPV6_RECVRSSBUCKETID:
1805                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1806                                         break;
1807 #endif
1808
1809                                 case IPV6_V6ONLY:
1810                                         INP_WLOCK(inp);
1811                                         if (inp->inp_lport ||
1812                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1813                                                 /*
1814                                                  * The socket is already bound.
1815                                                  */
1816                                                 INP_WUNLOCK(inp);
1817                                                 error = EINVAL;
1818                                                 break;
1819                                         }
1820                                         if (optval) {
1821                                                 inp->inp_flags |= IN6P_IPV6_V6ONLY;
1822                                                 inp->inp_vflag &= ~INP_IPV4;
1823                                         } else {
1824                                                 inp->inp_flags &= ~IN6P_IPV6_V6ONLY;
1825                                                 inp->inp_vflag |= INP_IPV4;
1826                                         }
1827                                         INP_WUNLOCK(inp);
1828                                         break;
1829                                 case IPV6_RECVTCLASS:
1830                                         /* cannot mix with RFC2292 XXX */
1831                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1832                                         break;
1833                                 case IPV6_AUTOFLOWLABEL:
1834                                         OPTSET(IN6P_AUTOFLOWLABEL);
1835                                         break;
1836
1837                                 case IPV6_ORIGDSTADDR:
1838                                         OPTSET2(INP_ORIGDSTADDR, optval);
1839                                         break;
1840                                 case IPV6_BINDANY:
1841                                         OPTSET(INP_BINDANY);
1842                                         break;
1843
1844                                 case IPV6_BINDMULTI:
1845                                         OPTSET2(INP_BINDMULTI, optval);
1846                                         break;
1847 #ifdef  RSS
1848                                 case IPV6_RSS_LISTEN_BUCKET:
1849                                         if ((optval >= 0) &&
1850                                             (optval < rss_getnumbuckets())) {
1851                                                 INP_WLOCK(inp);
1852                                                 inp->inp_rss_listen_bucket = optval;
1853                                                 OPTSET2_N(INP_RSS_BUCKET_SET, 1);
1854                                                 INP_WUNLOCK(inp);
1855                                         } else {
1856                                                 error = EINVAL;
1857                                         }
1858                                         break;
1859 #endif
1860                                 }
1861                                 break;
1862
1863                         case IPV6_TCLASS:
1864                         case IPV6_DONTFRAG:
1865                         case IPV6_USE_MIN_MTU:
1866                         case IPV6_PREFER_TEMPADDR:
1867                                 if (optlen != sizeof(optval)) {
1868                                         error = EINVAL;
1869                                         break;
1870                                 }
1871                                 error = sooptcopyin(sopt, &optval,
1872                                         sizeof optval, sizeof optval);
1873                                 if (error)
1874                                         break;
1875                                 {
1876                                         struct ip6_pktopts **optp;
1877                                         INP_WLOCK(inp);
1878                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1879                                                 INP_WUNLOCK(inp);
1880                                                 return (ECONNRESET);
1881                                         }
1882                                         optp = &inp->in6p_outputopts;
1883                                         error = ip6_pcbopt(optname,
1884                                             (u_char *)&optval, sizeof(optval),
1885                                             optp, (td != NULL) ? td->td_ucred :
1886                                             NULL, uproto);
1887                                         INP_WUNLOCK(inp);
1888                                         break;
1889                                 }
1890
1891                         case IPV6_2292PKTINFO:
1892                         case IPV6_2292HOPLIMIT:
1893                         case IPV6_2292HOPOPTS:
1894                         case IPV6_2292DSTOPTS:
1895                         case IPV6_2292RTHDR:
1896                                 /* RFC 2292 */
1897                                 if (optlen != sizeof(int)) {
1898                                         error = EINVAL;
1899                                         break;
1900                                 }
1901                                 error = sooptcopyin(sopt, &optval,
1902                                         sizeof optval, sizeof optval);
1903                                 if (error)
1904                                         break;
1905                                 switch (optname) {
1906                                 case IPV6_2292PKTINFO:
1907                                         OPTSET2292(IN6P_PKTINFO);
1908                                         break;
1909                                 case IPV6_2292HOPLIMIT:
1910                                         OPTSET2292(IN6P_HOPLIMIT);
1911                                         break;
1912                                 case IPV6_2292HOPOPTS:
1913                                         /*
1914                                          * Check super-user privilege.
1915                                          * See comments for IPV6_RECVHOPOPTS.
1916                                          */
1917                                         if (td != NULL) {
1918                                                 error = priv_check(td,
1919                                                     PRIV_NETINET_SETHDROPTS);
1920                                                 if (error)
1921                                                         return (error);
1922                                         }
1923                                         OPTSET2292(IN6P_HOPOPTS);
1924                                         break;
1925                                 case IPV6_2292DSTOPTS:
1926                                         if (td != NULL) {
1927                                                 error = priv_check(td,
1928                                                     PRIV_NETINET_SETHDROPTS);
1929                                                 if (error)
1930                                                         return (error);
1931                                         }
1932                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1933                                         break;
1934                                 case IPV6_2292RTHDR:
1935                                         OPTSET2292(IN6P_RTHDR);
1936                                         break;
1937                                 }
1938                                 break;
1939                         case IPV6_PKTINFO:
1940                         case IPV6_HOPOPTS:
1941                         case IPV6_RTHDR:
1942                         case IPV6_DSTOPTS:
1943                         case IPV6_RTHDRDSTOPTS:
1944                         case IPV6_NEXTHOP:
1945                         {
1946                                 /* new advanced API (RFC3542) */
1947                                 u_char *optbuf;
1948                                 u_char optbuf_storage[MCLBYTES];
1949                                 int optlen;
1950                                 struct ip6_pktopts **optp;
1951
1952                                 /* cannot mix with RFC2292 */
1953                                 if (OPTBIT(IN6P_RFC2292)) {
1954                                         error = EINVAL;
1955                                         break;
1956                                 }
1957
1958                                 /*
1959                                  * We only ensure valsize is not too large
1960                                  * here.  Further validation will be done
1961                                  * later.
1962                                  */
1963                                 error = sooptcopyin(sopt, optbuf_storage,
1964                                     sizeof(optbuf_storage), 0);
1965                                 if (error)
1966                                         break;
1967                                 optlen = sopt->sopt_valsize;
1968                                 optbuf = optbuf_storage;
1969                                 INP_WLOCK(inp);
1970                                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1971                                         INP_WUNLOCK(inp);
1972                                         return (ECONNRESET);
1973                                 }
1974                                 optp = &inp->in6p_outputopts;
1975                                 error = ip6_pcbopt(optname, optbuf, optlen,
1976                                     optp, (td != NULL) ? td->td_ucred : NULL,
1977                                     uproto);
1978                                 INP_WUNLOCK(inp);
1979                                 break;
1980                         }
1981 #undef OPTSET
1982
1983                         case IPV6_MULTICAST_IF:
1984                         case IPV6_MULTICAST_HOPS:
1985                         case IPV6_MULTICAST_LOOP:
1986                         case IPV6_JOIN_GROUP:
1987                         case IPV6_LEAVE_GROUP:
1988                         case IPV6_MSFILTER:
1989                         case MCAST_BLOCK_SOURCE:
1990                         case MCAST_UNBLOCK_SOURCE:
1991                         case MCAST_JOIN_GROUP:
1992                         case MCAST_LEAVE_GROUP:
1993                         case MCAST_JOIN_SOURCE_GROUP:
1994                         case MCAST_LEAVE_SOURCE_GROUP:
1995                                 error = ip6_setmoptions(inp, sopt);
1996                                 break;
1997
1998                         case IPV6_PORTRANGE:
1999                                 error = sooptcopyin(sopt, &optval,
2000                                     sizeof optval, sizeof optval);
2001                                 if (error)
2002                                         break;
2003
2004                                 INP_WLOCK(inp);
2005                                 switch (optval) {
2006                                 case IPV6_PORTRANGE_DEFAULT:
2007                                         inp->inp_flags &= ~(INP_LOWPORT);
2008                                         inp->inp_flags &= ~(INP_HIGHPORT);
2009                                         break;
2010
2011                                 case IPV6_PORTRANGE_HIGH:
2012                                         inp->inp_flags &= ~(INP_LOWPORT);
2013                                         inp->inp_flags |= INP_HIGHPORT;
2014                                         break;
2015
2016                                 case IPV6_PORTRANGE_LOW:
2017                                         inp->inp_flags &= ~(INP_HIGHPORT);
2018                                         inp->inp_flags |= INP_LOWPORT;
2019                                         break;
2020
2021                                 default:
2022                                         error = EINVAL;
2023                                         break;
2024                                 }
2025                                 INP_WUNLOCK(inp);
2026                                 break;
2027
2028 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2029                         case IPV6_IPSEC_POLICY:
2030                                 if (IPSEC_ENABLED(ipv6)) {
2031                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2032                                         break;
2033                                 }
2034                                 /* FALLTHROUGH */
2035 #endif /* IPSEC */
2036
2037                         default:
2038                                 error = ENOPROTOOPT;
2039                                 break;
2040                         }
2041                         break;
2042
2043                 case SOPT_GET:
2044                         switch (optname) {
2045
2046                         case IPV6_2292PKTOPTIONS:
2047 #ifdef IPV6_PKTOPTIONS
2048                         case IPV6_PKTOPTIONS:
2049 #endif
2050                                 /*
2051                                  * RFC3542 (effectively) deprecated the
2052                                  * semantics of the 2292-style pktoptions.
2053                                  * Since it was not reliable in nature (i.e.,
2054                                  * applications had to expect the lack of some
2055                                  * information after all), it would make sense
2056                                  * to simplify this part by always returning
2057                                  * empty data.
2058                                  */
2059                                 sopt->sopt_valsize = 0;
2060                                 break;
2061
2062                         case IPV6_RECVHOPOPTS:
2063                         case IPV6_RECVDSTOPTS:
2064                         case IPV6_RECVRTHDRDSTOPTS:
2065                         case IPV6_UNICAST_HOPS:
2066                         case IPV6_RECVPKTINFO:
2067                         case IPV6_RECVHOPLIMIT:
2068                         case IPV6_RECVRTHDR:
2069                         case IPV6_RECVPATHMTU:
2070
2071                         case IPV6_V6ONLY:
2072                         case IPV6_PORTRANGE:
2073                         case IPV6_RECVTCLASS:
2074                         case IPV6_AUTOFLOWLABEL:
2075                         case IPV6_BINDANY:
2076                         case IPV6_FLOWID:
2077                         case IPV6_FLOWTYPE:
2078                         case IPV6_RECVFLOWID:
2079 #ifdef  RSS
2080                         case IPV6_RSSBUCKETID:
2081                         case IPV6_RECVRSSBUCKETID:
2082 #endif
2083                         case IPV6_BINDMULTI:
2084                                 switch (optname) {
2085
2086                                 case IPV6_RECVHOPOPTS:
2087                                         optval = OPTBIT(IN6P_HOPOPTS);
2088                                         break;
2089
2090                                 case IPV6_RECVDSTOPTS:
2091                                         optval = OPTBIT(IN6P_DSTOPTS);
2092                                         break;
2093
2094                                 case IPV6_RECVRTHDRDSTOPTS:
2095                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2096                                         break;
2097
2098                                 case IPV6_UNICAST_HOPS:
2099                                         optval = inp->in6p_hops;
2100                                         break;
2101
2102                                 case IPV6_RECVPKTINFO:
2103                                         optval = OPTBIT(IN6P_PKTINFO);
2104                                         break;
2105
2106                                 case IPV6_RECVHOPLIMIT:
2107                                         optval = OPTBIT(IN6P_HOPLIMIT);
2108                                         break;
2109
2110                                 case IPV6_RECVRTHDR:
2111                                         optval = OPTBIT(IN6P_RTHDR);
2112                                         break;
2113
2114                                 case IPV6_RECVPATHMTU:
2115                                         optval = OPTBIT(IN6P_MTU);
2116                                         break;
2117
2118                                 case IPV6_V6ONLY:
2119                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2120                                         break;
2121
2122                                 case IPV6_PORTRANGE:
2123                                     {
2124                                         int flags;
2125                                         flags = inp->inp_flags;
2126                                         if (flags & INP_HIGHPORT)
2127                                                 optval = IPV6_PORTRANGE_HIGH;
2128                                         else if (flags & INP_LOWPORT)
2129                                                 optval = IPV6_PORTRANGE_LOW;
2130                                         else
2131                                                 optval = 0;
2132                                         break;
2133                                     }
2134                                 case IPV6_RECVTCLASS:
2135                                         optval = OPTBIT(IN6P_TCLASS);
2136                                         break;
2137
2138                                 case IPV6_AUTOFLOWLABEL:
2139                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2140                                         break;
2141
2142                                 case IPV6_ORIGDSTADDR:
2143                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2144                                         break;
2145
2146                                 case IPV6_BINDANY:
2147                                         optval = OPTBIT(INP_BINDANY);
2148                                         break;
2149
2150                                 case IPV6_FLOWID:
2151                                         optval = inp->inp_flowid;
2152                                         break;
2153
2154                                 case IPV6_FLOWTYPE:
2155                                         optval = inp->inp_flowtype;
2156                                         break;
2157
2158                                 case IPV6_RECVFLOWID:
2159                                         optval = OPTBIT2(INP_RECVFLOWID);
2160                                         break;
2161 #ifdef  RSS
2162                                 case IPV6_RSSBUCKETID:
2163                                         retval =
2164                                             rss_hash2bucket(inp->inp_flowid,
2165                                             inp->inp_flowtype,
2166                                             &rss_bucket);
2167                                         if (retval == 0)
2168                                                 optval = rss_bucket;
2169                                         else
2170                                                 error = EINVAL;
2171                                         break;
2172
2173                                 case IPV6_RECVRSSBUCKETID:
2174                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2175                                         break;
2176 #endif
2177
2178                                 case IPV6_BINDMULTI:
2179                                         optval = OPTBIT2(INP_BINDMULTI);
2180                                         break;
2181
2182                                 }
2183                                 if (error)
2184                                         break;
2185                                 error = sooptcopyout(sopt, &optval,
2186                                         sizeof optval);
2187                                 break;
2188
2189                         case IPV6_PATHMTU:
2190                         {
2191                                 u_long pmtu = 0;
2192                                 struct ip6_mtuinfo mtuinfo;
2193                                 struct in6_addr addr;
2194
2195                                 if (!(so->so_state & SS_ISCONNECTED))
2196                                         return (ENOTCONN);
2197                                 /*
2198                                  * XXX: we dot not consider the case of source
2199                                  * routing, or optional information to specify
2200                                  * the outgoing interface.
2201                                  * Copy faddr out of inp to avoid holding lock
2202                                  * on inp during route lookup.
2203                                  */
2204                                 INP_RLOCK(inp);
2205                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2206                                 INP_RUNLOCK(inp);
2207                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2208                                     &addr, &pmtu);
2209                                 if (error)
2210                                         break;
2211                                 if (pmtu > IPV6_MAXPACKET)
2212                                         pmtu = IPV6_MAXPACKET;
2213
2214                                 bzero(&mtuinfo, sizeof(mtuinfo));
2215                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2216                                 optdata = (void *)&mtuinfo;
2217                                 optdatalen = sizeof(mtuinfo);
2218                                 error = sooptcopyout(sopt, optdata,
2219                                     optdatalen);
2220                                 break;
2221                         }
2222
2223                         case IPV6_2292PKTINFO:
2224                         case IPV6_2292HOPLIMIT:
2225                         case IPV6_2292HOPOPTS:
2226                         case IPV6_2292RTHDR:
2227                         case IPV6_2292DSTOPTS:
2228                                 switch (optname) {
2229                                 case IPV6_2292PKTINFO:
2230                                         optval = OPTBIT(IN6P_PKTINFO);
2231                                         break;
2232                                 case IPV6_2292HOPLIMIT:
2233                                         optval = OPTBIT(IN6P_HOPLIMIT);
2234                                         break;
2235                                 case IPV6_2292HOPOPTS:
2236                                         optval = OPTBIT(IN6P_HOPOPTS);
2237                                         break;
2238                                 case IPV6_2292RTHDR:
2239                                         optval = OPTBIT(IN6P_RTHDR);
2240                                         break;
2241                                 case IPV6_2292DSTOPTS:
2242                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2243                                         break;
2244                                 }
2245                                 error = sooptcopyout(sopt, &optval,
2246                                     sizeof optval);
2247                                 break;
2248                         case IPV6_PKTINFO:
2249                         case IPV6_HOPOPTS:
2250                         case IPV6_RTHDR:
2251                         case IPV6_DSTOPTS:
2252                         case IPV6_RTHDRDSTOPTS:
2253                         case IPV6_NEXTHOP:
2254                         case IPV6_TCLASS:
2255                         case IPV6_DONTFRAG:
2256                         case IPV6_USE_MIN_MTU:
2257                         case IPV6_PREFER_TEMPADDR:
2258                                 error = ip6_getpcbopt(inp, optname, sopt);
2259                                 break;
2260
2261                         case IPV6_MULTICAST_IF:
2262                         case IPV6_MULTICAST_HOPS:
2263                         case IPV6_MULTICAST_LOOP:
2264                         case IPV6_MSFILTER:
2265                                 error = ip6_getmoptions(inp, sopt);
2266                                 break;
2267
2268 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2269                         case IPV6_IPSEC_POLICY:
2270                                 if (IPSEC_ENABLED(ipv6)) {
2271                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2272                                         break;
2273                                 }
2274                                 /* FALLTHROUGH */
2275 #endif /* IPSEC */
2276                         default:
2277                                 error = ENOPROTOOPT;
2278                                 break;
2279                         }
2280                         break;
2281                 }
2282         }
2283         return (error);
2284 }
2285
2286 int
2287 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2288 {
2289         int error = 0, optval, optlen;
2290         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2291         struct inpcb *inp = sotoinpcb(so);
2292         int level, op, optname;
2293
2294         level = sopt->sopt_level;
2295         op = sopt->sopt_dir;
2296         optname = sopt->sopt_name;
2297         optlen = sopt->sopt_valsize;
2298
2299         if (level != IPPROTO_IPV6) {
2300                 return (EINVAL);
2301         }
2302
2303         switch (optname) {
2304         case IPV6_CHECKSUM:
2305                 /*
2306                  * For ICMPv6 sockets, no modification allowed for checksum
2307                  * offset, permit "no change" values to help existing apps.
2308                  *
2309                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2310                  * for an ICMPv6 socket will fail."
2311                  * The current behavior does not meet RFC3542.
2312                  */
2313                 switch (op) {
2314                 case SOPT_SET:
2315                         if (optlen != sizeof(int)) {
2316                                 error = EINVAL;
2317                                 break;
2318                         }
2319                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2320                                             sizeof(optval));
2321                         if (error)
2322                                 break;
2323                         if (optval < -1 || (optval % 2) != 0) {
2324                                 /*
2325                                  * The API assumes non-negative even offset
2326                                  * values or -1 as a special value.
2327                                  */
2328                                 error = EINVAL;
2329                         } else if (so->so_proto->pr_protocol ==
2330                             IPPROTO_ICMPV6) {
2331                                 if (optval != icmp6off)
2332                                         error = EINVAL;
2333                         } else
2334                                 inp->in6p_cksum = optval;
2335                         break;
2336
2337                 case SOPT_GET:
2338                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2339                                 optval = icmp6off;
2340                         else
2341                                 optval = inp->in6p_cksum;
2342
2343                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2344                         break;
2345
2346                 default:
2347                         error = EINVAL;
2348                         break;
2349                 }
2350                 break;
2351
2352         default:
2353                 error = ENOPROTOOPT;
2354                 break;
2355         }
2356
2357         return (error);
2358 }
2359
2360 /*
2361  * Set up IP6 options in pcb for insertion in output packets or
2362  * specifying behavior of outgoing packets.
2363  */
2364 static int
2365 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2366     struct socket *so, struct sockopt *sopt)
2367 {
2368         struct ip6_pktopts *opt = *pktopt;
2369         int error = 0;
2370         struct thread *td = sopt->sopt_td;
2371
2372         /* turn off any old options. */
2373         if (opt) {
2374 #ifdef DIAGNOSTIC
2375                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2376                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2377                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2378                         printf("ip6_pcbopts: all specified options are cleared.\n");
2379 #endif
2380                 ip6_clearpktopts(opt, -1);
2381         } else
2382                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2383         *pktopt = NULL;
2384
2385         if (!m || m->m_len == 0) {
2386                 /*
2387                  * Only turning off any previous options, regardless of
2388                  * whether the opt is just created or given.
2389                  */
2390                 free(opt, M_IP6OPT);
2391                 return (0);
2392         }
2393
2394         /*  set options specified by user. */
2395         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2396             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2397                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2398                 free(opt, M_IP6OPT);
2399                 return (error);
2400         }
2401         *pktopt = opt;
2402         return (0);
2403 }
2404
2405 /*
2406  * initialize ip6_pktopts.  beware that there are non-zero default values in
2407  * the struct.
2408  */
2409 void
2410 ip6_initpktopts(struct ip6_pktopts *opt)
2411 {
2412
2413         bzero(opt, sizeof(*opt));
2414         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2415         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2416         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2417         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2418 }
2419
2420 static int
2421 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2422     struct ucred *cred, int uproto)
2423 {
2424         struct ip6_pktopts *opt;
2425
2426         if (*pktopt == NULL) {
2427                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2428                     M_NOWAIT);
2429                 if (*pktopt == NULL)
2430                         return (ENOBUFS);
2431                 ip6_initpktopts(*pktopt);
2432         }
2433         opt = *pktopt;
2434
2435         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2436 }
2437
2438 #define GET_PKTOPT_VAR(field, lenexpr) do {                                     \
2439         if (pktopt && pktopt->field) {                                          \
2440                 INP_RUNLOCK(inp);                                               \
2441                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK);         \
2442                 malloc_optdata = true;                                          \
2443                 INP_RLOCK(inp);                                                 \
2444                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {            \
2445                         INP_RUNLOCK(inp);                                       \
2446                         free(optdata, M_TEMP);                                  \
2447                         return (ECONNRESET);                                    \
2448                 }                                                               \
2449                 pktopt = inp->in6p_outputopts;                                  \
2450                 if (pktopt && pktopt->field) {                                  \
2451                         optdatalen = min(lenexpr, sopt->sopt_valsize);          \
2452                         bcopy(&pktopt->field, optdata, optdatalen);             \
2453                 } else {                                                        \
2454                         free(optdata, M_TEMP);                                  \
2455                         optdata = NULL;                                         \
2456                         malloc_optdata = false;                                 \
2457                 }                                                               \
2458         }                                                                       \
2459 } while(0)
2460
2461 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                         \
2462         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2463
2464 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                        \
2465         pktopt->field->sa_len)
2466
2467 static int
2468 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2469 {
2470         void *optdata = NULL;
2471         bool malloc_optdata = false;
2472         int optdatalen = 0;
2473         int error = 0;
2474         struct in6_pktinfo null_pktinfo;
2475         int deftclass = 0, on;
2476         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2477         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2478         struct ip6_pktopts *pktopt;
2479
2480         INP_RLOCK(inp);
2481         pktopt = inp->in6p_outputopts;
2482
2483         switch (optname) {
2484         case IPV6_PKTINFO:
2485                 optdata = (void *)&null_pktinfo;
2486                 if (pktopt && pktopt->ip6po_pktinfo) {
2487                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2488                             sizeof(null_pktinfo));
2489                         in6_clearscope(&null_pktinfo.ipi6_addr);
2490                 } else {
2491                         /* XXX: we don't have to do this every time... */
2492                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2493                 }
2494                 optdatalen = sizeof(struct in6_pktinfo);
2495                 break;
2496         case IPV6_TCLASS:
2497                 if (pktopt && pktopt->ip6po_tclass >= 0)
2498                         deftclass = pktopt->ip6po_tclass;
2499                 optdata = (void *)&deftclass;
2500                 optdatalen = sizeof(int);
2501                 break;
2502         case IPV6_HOPOPTS:
2503                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2504                 break;
2505         case IPV6_RTHDR:
2506                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2507                 break;
2508         case IPV6_RTHDRDSTOPTS:
2509                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2510                 break;
2511         case IPV6_DSTOPTS:
2512                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2513                 break;
2514         case IPV6_NEXTHOP:
2515                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2516                 break;
2517         case IPV6_USE_MIN_MTU:
2518                 if (pktopt)
2519                         defminmtu = pktopt->ip6po_minmtu;
2520                 optdata = (void *)&defminmtu;
2521                 optdatalen = sizeof(int);
2522                 break;
2523         case IPV6_DONTFRAG:
2524                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2525                         on = 1;
2526                 else
2527                         on = 0;
2528                 optdata = (void *)&on;
2529                 optdatalen = sizeof(on);
2530                 break;
2531         case IPV6_PREFER_TEMPADDR:
2532                 if (pktopt)
2533                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2534                 optdata = (void *)&defpreftemp;
2535                 optdatalen = sizeof(int);
2536                 break;
2537         default:                /* should not happen */
2538 #ifdef DIAGNOSTIC
2539                 panic("ip6_getpcbopt: unexpected option\n");
2540 #endif
2541                 INP_RUNLOCK(inp);
2542                 return (ENOPROTOOPT);
2543         }
2544         INP_RUNLOCK(inp);
2545
2546         error = sooptcopyout(sopt, optdata, optdatalen);
2547         if (malloc_optdata)
2548                 free(optdata, M_TEMP);
2549
2550         return (error);
2551 }
2552
2553 void
2554 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2555 {
2556         if (pktopt == NULL)
2557                 return;
2558
2559         if (optname == -1 || optname == IPV6_PKTINFO) {
2560                 if (pktopt->ip6po_pktinfo)
2561                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2562                 pktopt->ip6po_pktinfo = NULL;
2563         }
2564         if (optname == -1 || optname == IPV6_HOPLIMIT)
2565                 pktopt->ip6po_hlim = -1;
2566         if (optname == -1 || optname == IPV6_TCLASS)
2567                 pktopt->ip6po_tclass = -1;
2568         if (optname == -1 || optname == IPV6_NEXTHOP) {
2569                 if (pktopt->ip6po_nextroute.ro_rt) {
2570                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2571                         pktopt->ip6po_nextroute.ro_rt = NULL;
2572                 }
2573                 if (pktopt->ip6po_nexthop)
2574                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2575                 pktopt->ip6po_nexthop = NULL;
2576         }
2577         if (optname == -1 || optname == IPV6_HOPOPTS) {
2578                 if (pktopt->ip6po_hbh)
2579                         free(pktopt->ip6po_hbh, M_IP6OPT);
2580                 pktopt->ip6po_hbh = NULL;
2581         }
2582         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2583                 if (pktopt->ip6po_dest1)
2584                         free(pktopt->ip6po_dest1, M_IP6OPT);
2585                 pktopt->ip6po_dest1 = NULL;
2586         }
2587         if (optname == -1 || optname == IPV6_RTHDR) {
2588                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2589                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2590                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2591                 if (pktopt->ip6po_route.ro_rt) {
2592                         RTFREE(pktopt->ip6po_route.ro_rt);
2593                         pktopt->ip6po_route.ro_rt = NULL;
2594                 }
2595         }
2596         if (optname == -1 || optname == IPV6_DSTOPTS) {
2597                 if (pktopt->ip6po_dest2)
2598                         free(pktopt->ip6po_dest2, M_IP6OPT);
2599                 pktopt->ip6po_dest2 = NULL;
2600         }
2601 }
2602
2603 #define PKTOPT_EXTHDRCPY(type) \
2604 do {\
2605         if (src->type) {\
2606                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2607                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2608                 if (dst->type == NULL)\
2609                         goto bad;\
2610                 bcopy(src->type, dst->type, hlen);\
2611         }\
2612 } while (/*CONSTCOND*/ 0)
2613
2614 static int
2615 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2616 {
2617         if (dst == NULL || src == NULL)  {
2618                 printf("ip6_clearpktopts: invalid argument\n");
2619                 return (EINVAL);
2620         }
2621
2622         dst->ip6po_hlim = src->ip6po_hlim;
2623         dst->ip6po_tclass = src->ip6po_tclass;
2624         dst->ip6po_flags = src->ip6po_flags;
2625         dst->ip6po_minmtu = src->ip6po_minmtu;
2626         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2627         if (src->ip6po_pktinfo) {
2628                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2629                     M_IP6OPT, canwait);
2630                 if (dst->ip6po_pktinfo == NULL)
2631                         goto bad;
2632                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2633         }
2634         if (src->ip6po_nexthop) {
2635                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2636                     M_IP6OPT, canwait);
2637                 if (dst->ip6po_nexthop == NULL)
2638                         goto bad;
2639                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2640                     src->ip6po_nexthop->sa_len);
2641         }
2642         PKTOPT_EXTHDRCPY(ip6po_hbh);
2643         PKTOPT_EXTHDRCPY(ip6po_dest1);
2644         PKTOPT_EXTHDRCPY(ip6po_dest2);
2645         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2646         return (0);
2647
2648   bad:
2649         ip6_clearpktopts(dst, -1);
2650         return (ENOBUFS);
2651 }
2652 #undef PKTOPT_EXTHDRCPY
2653
2654 struct ip6_pktopts *
2655 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2656 {
2657         int error;
2658         struct ip6_pktopts *dst;
2659
2660         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2661         if (dst == NULL)
2662                 return (NULL);
2663         ip6_initpktopts(dst);
2664
2665         if ((error = copypktopts(dst, src, canwait)) != 0) {
2666                 free(dst, M_IP6OPT);
2667                 return (NULL);
2668         }
2669
2670         return (dst);
2671 }
2672
2673 void
2674 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2675 {
2676         if (pktopt == NULL)
2677                 return;
2678
2679         ip6_clearpktopts(pktopt, -1);
2680
2681         free(pktopt, M_IP6OPT);
2682 }
2683
2684 /*
2685  * Set IPv6 outgoing packet options based on advanced API.
2686  */
2687 int
2688 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2689     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2690 {
2691         struct cmsghdr *cm = NULL;
2692
2693         if (control == NULL || opt == NULL)
2694                 return (EINVAL);
2695
2696         ip6_initpktopts(opt);
2697         if (stickyopt) {
2698                 int error;
2699
2700                 /*
2701                  * If stickyopt is provided, make a local copy of the options
2702                  * for this particular packet, then override them by ancillary
2703                  * objects.
2704                  * XXX: copypktopts() does not copy the cached route to a next
2705                  * hop (if any).  This is not very good in terms of efficiency,
2706                  * but we can allow this since this option should be rarely
2707                  * used.
2708                  */
2709                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2710                         return (error);
2711         }
2712
2713         /*
2714          * XXX: Currently, we assume all the optional information is stored
2715          * in a single mbuf.
2716          */
2717         if (control->m_next)
2718                 return (EINVAL);
2719
2720         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2721             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2722                 int error;
2723
2724                 if (control->m_len < CMSG_LEN(0))
2725                         return (EINVAL);
2726
2727                 cm = mtod(control, struct cmsghdr *);
2728                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2729                         return (EINVAL);
2730                 if (cm->cmsg_level != IPPROTO_IPV6)
2731                         continue;
2732
2733                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2734                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2735                 if (error)
2736                         return (error);
2737         }
2738
2739         return (0);
2740 }
2741
2742 /*
2743  * Set a particular packet option, as a sticky option or an ancillary data
2744  * item.  "len" can be 0 only when it's a sticky option.
2745  * We have 4 cases of combination of "sticky" and "cmsg":
2746  * "sticky=0, cmsg=0": impossible
2747  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2748  * "sticky=1, cmsg=0": RFC3542 socket option
2749  * "sticky=1, cmsg=1": RFC2292 socket option
2750  */
2751 static int
2752 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2753     struct ucred *cred, int sticky, int cmsg, int uproto)
2754 {
2755         int minmtupolicy, preftemp;
2756         int error;
2757
2758         if (!sticky && !cmsg) {
2759 #ifdef DIAGNOSTIC
2760                 printf("ip6_setpktopt: impossible case\n");
2761 #endif
2762                 return (EINVAL);
2763         }
2764
2765         /*
2766          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2767          * not be specified in the context of RFC3542.  Conversely,
2768          * RFC3542 types should not be specified in the context of RFC2292.
2769          */
2770         if (!cmsg) {
2771                 switch (optname) {
2772                 case IPV6_2292PKTINFO:
2773                 case IPV6_2292HOPLIMIT:
2774                 case IPV6_2292NEXTHOP:
2775                 case IPV6_2292HOPOPTS:
2776                 case IPV6_2292DSTOPTS:
2777                 case IPV6_2292RTHDR:
2778                 case IPV6_2292PKTOPTIONS:
2779                         return (ENOPROTOOPT);
2780                 }
2781         }
2782         if (sticky && cmsg) {
2783                 switch (optname) {
2784                 case IPV6_PKTINFO:
2785                 case IPV6_HOPLIMIT:
2786                 case IPV6_NEXTHOP:
2787                 case IPV6_HOPOPTS:
2788                 case IPV6_DSTOPTS:
2789                 case IPV6_RTHDRDSTOPTS:
2790                 case IPV6_RTHDR:
2791                 case IPV6_USE_MIN_MTU:
2792                 case IPV6_DONTFRAG:
2793                 case IPV6_TCLASS:
2794                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2795                         return (ENOPROTOOPT);
2796                 }
2797         }
2798
2799         switch (optname) {
2800         case IPV6_2292PKTINFO:
2801         case IPV6_PKTINFO:
2802         {
2803                 struct ifnet *ifp = NULL;
2804                 struct in6_pktinfo *pktinfo;
2805
2806                 if (len != sizeof(struct in6_pktinfo))
2807                         return (EINVAL);
2808
2809                 pktinfo = (struct in6_pktinfo *)buf;
2810
2811                 /*
2812                  * An application can clear any sticky IPV6_PKTINFO option by
2813                  * doing a "regular" setsockopt with ipi6_addr being
2814                  * in6addr_any and ipi6_ifindex being zero.
2815                  * [RFC 3542, Section 6]
2816                  */
2817                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2818                     pktinfo->ipi6_ifindex == 0 &&
2819                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2820                         ip6_clearpktopts(opt, optname);
2821                         break;
2822                 }
2823
2824                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2825                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2826                         return (EINVAL);
2827                 }
2828                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2829                         return (EINVAL);
2830                 /* validate the interface index if specified. */
2831                 if (pktinfo->ipi6_ifindex > V_if_index)
2832                          return (ENXIO);
2833                 if (pktinfo->ipi6_ifindex) {
2834                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2835                         if (ifp == NULL)
2836                                 return (ENXIO);
2837                 }
2838                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2839                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2840                         return (ENETDOWN);
2841
2842                 if (ifp != NULL &&
2843                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2844                         struct in6_ifaddr *ia;
2845
2846                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2847                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2848                         if (ia == NULL)
2849                                 return (EADDRNOTAVAIL);
2850                         ifa_free(&ia->ia_ifa);
2851                 }
2852                 /*
2853                  * We store the address anyway, and let in6_selectsrc()
2854                  * validate the specified address.  This is because ipi6_addr
2855                  * may not have enough information about its scope zone, and
2856                  * we may need additional information (such as outgoing
2857                  * interface or the scope zone of a destination address) to
2858                  * disambiguate the scope.
2859                  * XXX: the delay of the validation may confuse the
2860                  * application when it is used as a sticky option.
2861                  */
2862                 if (opt->ip6po_pktinfo == NULL) {
2863                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2864                             M_IP6OPT, M_NOWAIT);
2865                         if (opt->ip6po_pktinfo == NULL)
2866                                 return (ENOBUFS);
2867                 }
2868                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2869                 break;
2870         }
2871
2872         case IPV6_2292HOPLIMIT:
2873         case IPV6_HOPLIMIT:
2874         {
2875                 int *hlimp;
2876
2877                 /*
2878                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2879                  * to simplify the ordering among hoplimit options.
2880                  */
2881                 if (optname == IPV6_HOPLIMIT && sticky)
2882                         return (ENOPROTOOPT);
2883
2884                 if (len != sizeof(int))
2885                         return (EINVAL);
2886                 hlimp = (int *)buf;
2887                 if (*hlimp < -1 || *hlimp > 255)
2888                         return (EINVAL);
2889
2890                 opt->ip6po_hlim = *hlimp;
2891                 break;
2892         }
2893
2894         case IPV6_TCLASS:
2895         {
2896                 int tclass;
2897
2898                 if (len != sizeof(int))
2899                         return (EINVAL);
2900                 tclass = *(int *)buf;
2901                 if (tclass < -1 || tclass > 255)
2902                         return (EINVAL);
2903
2904                 opt->ip6po_tclass = tclass;
2905                 break;
2906         }
2907
2908         case IPV6_2292NEXTHOP:
2909         case IPV6_NEXTHOP:
2910                 if (cred != NULL) {
2911                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2912                         if (error)
2913                                 return (error);
2914                 }
2915
2916                 if (len == 0) { /* just remove the option */
2917                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
2918                         break;
2919                 }
2920
2921                 /* check if cmsg_len is large enough for sa_len */
2922                 if (len < sizeof(struct sockaddr) || len < *buf)
2923                         return (EINVAL);
2924
2925                 switch (((struct sockaddr *)buf)->sa_family) {
2926                 case AF_INET6:
2927                 {
2928                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2929                         int error;
2930
2931                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2932                                 return (EINVAL);
2933
2934                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2935                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2936                                 return (EINVAL);
2937                         }
2938                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2939                             != 0) {
2940                                 return (error);
2941                         }
2942                         break;
2943                 }
2944                 case AF_LINK:   /* should eventually be supported */
2945                 default:
2946                         return (EAFNOSUPPORT);
2947                 }
2948
2949                 /* turn off the previous option, then set the new option. */
2950                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2951                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2952                 if (opt->ip6po_nexthop == NULL)
2953                         return (ENOBUFS);
2954                 bcopy(buf, opt->ip6po_nexthop, *buf);
2955                 break;
2956
2957         case IPV6_2292HOPOPTS:
2958         case IPV6_HOPOPTS:
2959         {
2960                 struct ip6_hbh *hbh;
2961                 int hbhlen;
2962
2963                 /*
2964                  * XXX: We don't allow a non-privileged user to set ANY HbH
2965                  * options, since per-option restriction has too much
2966                  * overhead.
2967                  */
2968                 if (cred != NULL) {
2969                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2970                         if (error)
2971                                 return (error);
2972                 }
2973
2974                 if (len == 0) {
2975                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
2976                         break;  /* just remove the option */
2977                 }
2978
2979                 /* message length validation */
2980                 if (len < sizeof(struct ip6_hbh))
2981                         return (EINVAL);
2982                 hbh = (struct ip6_hbh *)buf;
2983                 hbhlen = (hbh->ip6h_len + 1) << 3;
2984                 if (len != hbhlen)
2985                         return (EINVAL);
2986
2987                 /* turn off the previous option, then set the new option. */
2988                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2989                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2990                 if (opt->ip6po_hbh == NULL)
2991                         return (ENOBUFS);
2992                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2993
2994                 break;
2995         }
2996
2997         case IPV6_2292DSTOPTS:
2998         case IPV6_DSTOPTS:
2999         case IPV6_RTHDRDSTOPTS:
3000         {
3001                 struct ip6_dest *dest, **newdest = NULL;
3002                 int destlen;
3003
3004                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
3005                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3006                         if (error)
3007                                 return (error);
3008                 }
3009
3010                 if (len == 0) {
3011                         ip6_clearpktopts(opt, optname);
3012                         break;  /* just remove the option */
3013                 }
3014
3015                 /* message length validation */
3016                 if (len < sizeof(struct ip6_dest))
3017                         return (EINVAL);
3018                 dest = (struct ip6_dest *)buf;
3019                 destlen = (dest->ip6d_len + 1) << 3;
3020                 if (len != destlen)
3021                         return (EINVAL);
3022
3023                 /*
3024                  * Determine the position that the destination options header
3025                  * should be inserted; before or after the routing header.
3026                  */
3027                 switch (optname) {
3028                 case IPV6_2292DSTOPTS:
3029                         /*
3030                          * The old advacned API is ambiguous on this point.
3031                          * Our approach is to determine the position based
3032                          * according to the existence of a routing header.
3033                          * Note, however, that this depends on the order of the
3034                          * extension headers in the ancillary data; the 1st
3035                          * part of the destination options header must appear
3036                          * before the routing header in the ancillary data,
3037                          * too.
3038                          * RFC3542 solved the ambiguity by introducing
3039                          * separate ancillary data or option types.
3040                          */
3041                         if (opt->ip6po_rthdr == NULL)
3042                                 newdest = &opt->ip6po_dest1;
3043                         else
3044                                 newdest = &opt->ip6po_dest2;
3045                         break;
3046                 case IPV6_RTHDRDSTOPTS:
3047                         newdest = &opt->ip6po_dest1;
3048                         break;
3049                 case IPV6_DSTOPTS:
3050                         newdest = &opt->ip6po_dest2;
3051                         break;
3052                 }
3053
3054                 /* turn off the previous option, then set the new option. */
3055                 ip6_clearpktopts(opt, optname);
3056                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3057                 if (*newdest == NULL)
3058                         return (ENOBUFS);
3059                 bcopy(dest, *newdest, destlen);
3060
3061                 break;
3062         }
3063
3064         case IPV6_2292RTHDR:
3065         case IPV6_RTHDR:
3066         {
3067                 struct ip6_rthdr *rth;
3068                 int rthlen;
3069
3070                 if (len == 0) {
3071                         ip6_clearpktopts(opt, IPV6_RTHDR);
3072                         break;  /* just remove the option */
3073                 }
3074
3075                 /* message length validation */
3076                 if (len < sizeof(struct ip6_rthdr))
3077                         return (EINVAL);
3078                 rth = (struct ip6_rthdr *)buf;
3079                 rthlen = (rth->ip6r_len + 1) << 3;
3080                 if (len != rthlen)
3081                         return (EINVAL);
3082
3083                 switch (rth->ip6r_type) {
3084                 case IPV6_RTHDR_TYPE_0:
3085                         if (rth->ip6r_len == 0) /* must contain one addr */
3086                                 return (EINVAL);
3087                         if (rth->ip6r_len % 2) /* length must be even */
3088                                 return (EINVAL);
3089                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3090                                 return (EINVAL);
3091                         break;
3092                 default:
3093                         return (EINVAL);        /* not supported */
3094                 }
3095
3096                 /* turn off the previous option */
3097                 ip6_clearpktopts(opt, IPV6_RTHDR);
3098                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3099                 if (opt->ip6po_rthdr == NULL)
3100                         return (ENOBUFS);
3101                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3102
3103                 break;
3104         }
3105
3106         case IPV6_USE_MIN_MTU:
3107                 if (len != sizeof(int))
3108                         return (EINVAL);
3109                 minmtupolicy = *(int *)buf;
3110                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3111                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3112                     minmtupolicy != IP6PO_MINMTU_ALL) {
3113                         return (EINVAL);
3114                 }
3115                 opt->ip6po_minmtu = minmtupolicy;
3116                 break;
3117
3118         case IPV6_DONTFRAG:
3119                 if (len != sizeof(int))
3120                         return (EINVAL);
3121
3122                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3123                         /*
3124                          * we ignore this option for TCP sockets.
3125                          * (RFC3542 leaves this case unspecified.)
3126                          */
3127                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3128                 } else
3129                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3130                 break;
3131
3132         case IPV6_PREFER_TEMPADDR:
3133                 if (len != sizeof(int))
3134                         return (EINVAL);
3135                 preftemp = *(int *)buf;
3136                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3137                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3138                     preftemp != IP6PO_TEMPADDR_PREFER) {
3139                         return (EINVAL);
3140                 }
3141                 opt->ip6po_prefer_tempaddr = preftemp;
3142                 break;
3143
3144         default:
3145                 return (ENOPROTOOPT);
3146         } /* end of switch */
3147
3148         return (0);
3149 }
3150
3151 /*
3152  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3153  * packet to the input queue of a specified interface.  Note that this
3154  * calls the output routine of the loopback "driver", but with an interface
3155  * pointer that might NOT be &loif -- easier than replicating that code here.
3156  */
3157 void
3158 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3159 {
3160         struct mbuf *copym;
3161         struct ip6_hdr *ip6;
3162
3163         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3164         if (copym == NULL)
3165                 return;
3166
3167         /*
3168          * Make sure to deep-copy IPv6 header portion in case the data
3169          * is in an mbuf cluster, so that we can safely override the IPv6
3170          * header portion later.
3171          */
3172         if (!M_WRITABLE(copym) ||
3173             copym->m_len < sizeof(struct ip6_hdr)) {
3174                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3175                 if (copym == NULL)
3176                         return;
3177         }
3178         ip6 = mtod(copym, struct ip6_hdr *);
3179         /*
3180          * clear embedded scope identifiers if necessary.
3181          * in6_clearscope will touch the addresses only when necessary.
3182          */
3183         in6_clearscope(&ip6->ip6_src);
3184         in6_clearscope(&ip6->ip6_dst);
3185         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3186                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3187                     CSUM_PSEUDO_HDR;
3188                 copym->m_pkthdr.csum_data = 0xffff;
3189         }
3190         if_simloop(ifp, copym, AF_INET6, 0);
3191 }
3192
3193 /*
3194  * Chop IPv6 header off from the payload.
3195  */
3196 static int
3197 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3198 {
3199         struct mbuf *mh;
3200         struct ip6_hdr *ip6;
3201
3202         ip6 = mtod(m, struct ip6_hdr *);
3203         if (m->m_len > sizeof(*ip6)) {
3204                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3205                 if (mh == NULL) {
3206                         m_freem(m);
3207                         return ENOBUFS;
3208                 }
3209                 m_move_pkthdr(mh, m);
3210                 M_ALIGN(mh, sizeof(*ip6));
3211                 m->m_len -= sizeof(*ip6);
3212                 m->m_data += sizeof(*ip6);
3213                 mh->m_next = m;
3214                 m = mh;
3215                 m->m_len = sizeof(*ip6);
3216                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3217         }
3218         exthdrs->ip6e_ip6 = m;
3219         return 0;
3220 }
3221
3222 /*
3223  * Compute IPv6 extension header length.
3224  */
3225 int
3226 ip6_optlen(struct inpcb *inp)
3227 {
3228         int len;
3229
3230         if (!inp->in6p_outputopts)
3231                 return 0;
3232
3233         len = 0;
3234 #define elen(x) \
3235     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3236
3237         len += elen(inp->in6p_outputopts->ip6po_hbh);
3238         if (inp->in6p_outputopts->ip6po_rthdr)
3239                 /* dest1 is valid with rthdr only */
3240                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3241         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3242         len += elen(inp->in6p_outputopts->ip6po_dest2);
3243         return len;
3244 #undef elen
3245 }