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 route_in6 ip6route;
 388         struct rtentry *rt = NULL;
 389         struct sockaddr_in6 *dst, src_sa, dst_sa;
 390         struct in6_addr odst;
 391         int error = 0;
 392         struct in6_ifaddr *ia = NULL;
 393         u_long mtu;
 394         int alwaysfrag, dontfrag;
 395         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 396         struct ip6_exthdrs exthdrs;
 397         struct in6_addr src0, dst0;
 398         u_int32_t zone;
 399         struct route_in6 *ro_pmtu = NULL;
 400         int hdrsplit = 0;
 401         int sw_csum, tso;
 402         int needfiblookup;
 403         uint32_t fibnum;
 404         struct m_tag *fwd_tag = NULL;
 405         uint32_t id;
 406
 407         if (inp != NULL) {
 408                 INP_LOCK_ASSERT(inp);
 409                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 410                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 411                         /* unconditionally set flowid */
 412                         m->m_pkthdr.flowid = inp->inp_flowid;
 413                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 414                 }
 415 #ifdef NUMA
 416                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 417 #endif
 418         }
 419
 420 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 421         /*
 422          * IPSec checking which handles several cases.
 423          * FAST IPSEC: We re-injected the packet.
 424          * XXX: need scope argument.
 425          */
 426         if (IPSEC_ENABLED(ipv6)) {
 427                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 428                         if (error == EINPROGRESS)
 429                                 error = 0;
 430                         goto done;
 431                 }
 432         }
 433 #endif /* IPSEC */
 434
 435         bzero(&exthdrs, sizeof(exthdrs));
 436         if (opt) {
 437                 /* Hop-by-Hop options header */
 438                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 439                 /* Destination options header(1st part) */
 440                 if (opt->ip6po_rthdr) {
 441                         /*
 442                          * Destination options header(1st part)
 443                          * This only makes sense with a routing header.
 444                          * See Section 9.2 of RFC 3542.
 445                          * Disabling this part just for MIP6 convenience is
 446                          * a bad idea.  We need to think carefully about a
 447                          * way to make the advanced API coexist with MIP6
 448                          * options, which might automatically be inserted in
 449                          * the kernel.
 450                          */
 451                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 452                 }
 453                 /* Routing header */
 454                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 455                 /* Destination options header(2nd part) */
 456                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 457         }
 458
 459         /*
 460          * Calculate the total length of the extension header chain.
 461          * Keep the length of the unfragmentable part for fragmentation.
 462          */
 463         optlen = 0;
 464         if (exthdrs.ip6e_hbh)
 465                 optlen += exthdrs.ip6e_hbh->m_len;
 466         if (exthdrs.ip6e_dest1)
 467                 optlen += exthdrs.ip6e_dest1->m_len;
 468         if (exthdrs.ip6e_rthdr)
 469                 optlen += exthdrs.ip6e_rthdr->m_len;
 470         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 471
 472         /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
 473         if (exthdrs.ip6e_dest2)
 474                 optlen += exthdrs.ip6e_dest2->m_len;
 475
 476         /*
 477          * If there is at least one extension header,
 478          * separate IP6 header from the payload.
 479          */
 480         if (optlen && !hdrsplit) {
 481                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 482                         m = NULL;
 483                         goto freehdrs;
 484                 }
 485                 m = exthdrs.ip6e_ip6;
 486                 hdrsplit++;
 487         }
 488
 489         ip6 = mtod(m, struct ip6_hdr *);
 490
 491         /* adjust mbuf packet header length */
 492         m->m_pkthdr.len += optlen;
 493         plen = m->m_pkthdr.len - sizeof(*ip6);
 494
 495         /* If this is a jumbo payload, insert a jumbo payload option. */
 496         if (plen > IPV6_MAXPACKET) {
 497                 if (!hdrsplit) {
 498                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 499                                 m = NULL;
 500                                 goto freehdrs;
 501                         }
 502                         m = exthdrs.ip6e_ip6;
 503                         hdrsplit++;
 504                 }
 505                 /* adjust pointer */
 506                 ip6 = mtod(m, struct ip6_hdr *);
 507                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 508                         goto freehdrs;
 509                 ip6->ip6_plen = 0;
 510         } else
 511                 ip6->ip6_plen = htons(plen);
 512
 513         /*
 514          * Concatenate headers and fill in next header fields.
 515          * Here we have, on "m"
 516          *      IPv6 payload
 517          * and we insert headers accordingly.  Finally, we should be getting:
 518          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 519          *
 520          * during the header composing process, "m" points to IPv6 header.
 521          * "mprev" points to an extension header prior to esp.
 522          */
 523         u_char *nexthdrp = &ip6->ip6_nxt;
 524         mprev = m;
 525
 526         /*
 527          * we treat dest2 specially.  this makes IPsec processing
 528          * much easier.  the goal here is to make mprev point the
 529          * mbuf prior to dest2.
 530          *
 531          * result: IPv6 dest2 payload
 532          * m and mprev will point to IPv6 header.
 533          */
 534         if (exthdrs.ip6e_dest2) {
 535                 if (!hdrsplit)
 536                         panic("assumption failed: hdr not split");
 537                 exthdrs.ip6e_dest2->m_next = m->m_next;
 538                 m->m_next = exthdrs.ip6e_dest2;
 539                 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 540                 ip6->ip6_nxt = IPPROTO_DSTOPTS;
 541         }
 542
 543         /*
 544          * result: IPv6 hbh dest1 rthdr dest2 payload
 545          * m will point to IPv6 header.  mprev will point to the
 546          * extension header prior to dest2 (rthdr in the above case).
 547          */
 548         MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 549         MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 550                    IPPROTO_DSTOPTS);
 551         MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 552                    IPPROTO_ROUTING);
 553
 554         /*
 555          * If there is a routing header, discard the packet.
 556          */
 557         if (exthdrs.ip6e_rthdr) {
 558                  error = EINVAL;
 559                  goto bad;
 560         }
 561
 562         /* Source address validation */
 563         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 564             (flags & IPV6_UNSPECSRC) == 0) {
 565                 error = EOPNOTSUPP;
 566                 IP6STAT_INC(ip6s_badscope);
 567                 goto bad;
 568         }
 569         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 570                 error = EOPNOTSUPP;
 571                 IP6STAT_INC(ip6s_badscope);
 572                 goto bad;
 573         }
 574
 575         IP6STAT_INC(ip6s_localout);
 576
 577         /*
 578          * Route packet.
 579          */
 580         if (ro == NULL) {
 581                 ro = &ip6route;
 582                 bzero((caddr_t)ro, sizeof(*ro));
 583         }
 584         ro_pmtu = ro;
 585         if (opt && opt->ip6po_rthdr)
 586                 ro = &opt->ip6po_route;
 587         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 588         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 589 again:
 590         /*
 591          * if specified, try to fill in the traffic class field.
 592          * do not override if a non-zero value is already set.
 593          * we check the diffserv field and the ecn field separately.
 594          */
 595         if (opt && opt->ip6po_tclass >= 0) {
 596                 int mask = 0;
 597
 598                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 599                         mask |= 0xfc;
 600                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 601                         mask |= 0x03;
 602                 if (mask != 0)
 603                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 604         }
 605
 606         /* fill in or override the hop limit field, if necessary. */
 607         if (opt && opt->ip6po_hlim != -1)
 608                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 609         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 610                 if (im6o != NULL)
 611                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 612                 else
 613                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 614         }
 615         /*
 616          * Validate route against routing table additions;
 617          * a better/more specific route might have been added.
 618          * Make sure address family is set in route.
 619          */
 620         if (inp) {
 621                 ro->ro_dst.sin6_family = AF_INET6;
 622                 RT_VALIDATE((struct route *)ro, &inp->inp_rt_cookie, fibnum);
 623         }
 624         if (ro->ro_rt && fwd_tag == NULL && (ro->ro_rt->rt_flags & RTF_UP) &&
 625             ro->ro_dst.sin6_family == AF_INET6 &&
 626             IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 627                 rt = ro->ro_rt;
 628                 ifp = ro->ro_rt->rt_ifp;
 629         } else {
 630                 if (ro->ro_lle)
 631                         LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 632                 ro->ro_lle = NULL;
 633                 if (fwd_tag == NULL) {
 634                         bzero(&dst_sa, sizeof(dst_sa));
 635                         dst_sa.sin6_family = AF_INET6;
 636                         dst_sa.sin6_len = sizeof(dst_sa);
 637                         dst_sa.sin6_addr = ip6->ip6_dst;
 638                 }
 639                 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
 640                     &rt, fibnum);
 641                 if (error != 0) {
 642                         if (ifp != NULL)
 643                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 644                         goto bad;
 645                 }
 646         }
 647         if (rt == NULL) {
 648                 /*
 649                  * If in6_selectroute() does not return a route entry,
 650                  * dst may not have been updated.
 651                  */
 652                 *dst = dst_sa;  /* XXX */
 653         }
 654
 655         /*
 656          * then rt (for unicast) and ifp must be non-NULL valid values.
 657          */
 658         if ((flags & IPV6_FORWARDING) == 0) {
 659                 /* XXX: the FORWARDING flag can be set for mrouting. */
 660                 in6_ifstat_inc(ifp, ifs6_out_request);
 661         }
 662         if (rt != NULL) {
 663                 ia = (struct in6_ifaddr *)(rt->rt_ifa);
 664                 counter_u64_add(rt->rt_pksent, 1);
 665         }
 666
 667         /* Setup data structures for scope ID checks. */
 668         src0 = ip6->ip6_src;
 669         bzero(&src_sa, sizeof(src_sa));
 670         src_sa.sin6_family = AF_INET6;
 671         src_sa.sin6_len = sizeof(src_sa);
 672         src_sa.sin6_addr = ip6->ip6_src;
 673
 674         dst0 = ip6->ip6_dst;
 675         /* re-initialize to be sure */
 676         bzero(&dst_sa, sizeof(dst_sa));
 677         dst_sa.sin6_family = AF_INET6;
 678         dst_sa.sin6_len = sizeof(dst_sa);
 679         dst_sa.sin6_addr = ip6->ip6_dst;
 680
 681         /* Check for valid scope ID. */
 682         if (in6_setscope(&src0, ifp, &zone) == 0 &&
 683             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 684             in6_setscope(&dst0, ifp, &zone) == 0 &&
 685             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 686                 /*
 687                  * The outgoing interface is in the zone of the source
 688                  * and destination addresses.
 689                  *
 690                  * Because the loopback interface cannot receive
 691                  * packets with a different scope ID than its own,
 692                  * there is a trick is to pretend the outgoing packet
 693                  * was received by the real network interface, by
 694                  * setting "origifp" different from "ifp". This is
 695                  * only allowed when "ifp" is a loopback network
 696                  * interface. Refer to code in nd6_output_ifp() for
 697                  * more details.
 698                  */
 699                 origifp = ifp;
 700
 701                 /*
 702                  * We should use ia_ifp to support the case of sending
 703                  * packets to an address of our own.
 704                  */
 705                 if (ia != NULL && ia->ia_ifp)
 706                         ifp = ia->ia_ifp;
 707
 708         } else if ((ifp->if_flags & IFF_LOOPBACK) == 0 ||
 709             sa6_recoverscope(&src_sa) != 0 ||
 710             sa6_recoverscope(&dst_sa) != 0 ||
 711             dst_sa.sin6_scope_id == 0 ||
 712             (src_sa.sin6_scope_id != 0 &&
 713             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 714             (origifp = ifnet_byindex(dst_sa.sin6_scope_id)) == NULL) {
 715                 /*
 716                  * If the destination network interface is not a
 717                  * loopback interface, or the destination network
 718                  * address has no scope ID, or the source address has
 719                  * a scope ID set which is different from the
 720                  * destination address one, or there is no network
 721                  * interface representing this scope ID, the address
 722                  * pair is considered invalid.
 723                  */
 724                 IP6STAT_INC(ip6s_badscope);
 725                 in6_ifstat_inc(ifp, ifs6_out_discard);
 726                 if (error == 0)
 727                         error = EHOSTUNREACH; /* XXX */
 728                 goto bad;
 729         }
 730
 731         /* All scope ID checks are successful. */
 732
 733         if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 734                 if (opt && opt->ip6po_nextroute.ro_rt) {
 735                         /*
 736                          * The nexthop is explicitly specified by the
 737                          * application.  We assume the next hop is an IPv6
 738                          * address.
 739                          */
 740                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 741                 }
 742                 else if ((rt->rt_flags & RTF_GATEWAY))
 743                         dst = (struct sockaddr_in6 *)rt->rt_gateway;
 744         }
 745
 746         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 747                 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
 748         } else {
 749                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 750                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 751                 /*
 752                  * Confirm that the outgoing interface supports multicast.
 753                  */
 754                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 755                         IP6STAT_INC(ip6s_noroute);
 756                         in6_ifstat_inc(ifp, ifs6_out_discard);
 757                         error = ENETUNREACH;
 758                         goto bad;
 759                 }
 760                 if ((im6o == NULL && in6_mcast_loop) ||
 761                     (im6o && im6o->im6o_multicast_loop)) {
 762                         /*
 763                          * Loop back multicast datagram if not expressly
 764                          * forbidden to do so, even if we have not joined
 765                          * the address; protocols will filter it later,
 766                          * thus deferring a hash lookup and lock acquisition
 767                          * at the expense of an m_copym().
 768                          */
 769                         ip6_mloopback(ifp, m);
 770                 } else {
 771                         /*
 772                          * If we are acting as a multicast router, perform
 773                          * multicast forwarding as if the packet had just
 774                          * arrived on the interface to which we are about
 775                          * to send.  The multicast forwarding function
 776                          * recursively calls this function, using the
 777                          * IPV6_FORWARDING flag to prevent infinite recursion.
 778                          *
 779                          * Multicasts that are looped back by ip6_mloopback(),
 780                          * above, will be forwarded by the ip6_input() routine,
 781                          * if necessary.
 782                          */
 783                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 784                                 /*
 785                                  * XXX: ip6_mforward expects that rcvif is NULL
 786                                  * when it is called from the originating path.
 787                                  * However, it may not always be the case.
 788                                  */
 789                                 m->m_pkthdr.rcvif = NULL;
 790                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 791                                         m_freem(m);
 792                                         goto done;
 793                                 }
 794                         }
 795                 }
 796                 /*
 797                  * Multicasts with a hoplimit of zero may be looped back,
 798                  * above, but must not be transmitted on a network.
 799                  * Also, multicasts addressed to the loopback interface
 800                  * are not sent -- the above call to ip6_mloopback() will
 801                  * loop back a copy if this host actually belongs to the
 802                  * destination group on the loopback interface.
 803                  */
 804                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 805                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 806                         m_freem(m);
 807                         goto done;
 808                 }
 809         }
 810
 811         /*
 812          * Fill the outgoing inteface to tell the upper layer
 813          * to increment per-interface statistics.
 814          */
 815         if (ifpp)
 816                 *ifpp = ifp;
 817
 818         /* Determine path MTU. */
 819         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 820                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 821                 goto bad;
 822
 823         /*
 824          * The caller of this function may specify to use the minimum MTU
 825          * in some cases.
 826          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 827          * setting.  The logic is a bit complicated; by default, unicast
 828          * packets will follow path MTU while multicast packets will be sent at
 829          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 830          * including unicast ones will be sent at the minimum MTU.  Multicast
 831          * packets will always be sent at the minimum MTU unless
 832          * IP6PO_MINMTU_DISABLE is explicitly specified.
 833          * See RFC 3542 for more details.
 834          */
 835         if (mtu > IPV6_MMTU) {
 836                 if ((flags & IPV6_MINMTU))
 837                         mtu = IPV6_MMTU;
 838                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 839                         mtu = IPV6_MMTU;
 840                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 841                          (opt == NULL ||
 842                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 843                         mtu = IPV6_MMTU;
 844                 }
 845         }
 846
 847         /*
 848          * clear embedded scope identifiers if necessary.
 849          * in6_clearscope will touch the addresses only when necessary.
 850          */
 851         in6_clearscope(&ip6->ip6_src);
 852         in6_clearscope(&ip6->ip6_dst);
 853
 854         /*
 855          * If the outgoing packet contains a hop-by-hop options header,
 856          * it must be examined and processed even by the source node.
 857          * (RFC 2460, section 4.)
 858          */
 859         if (exthdrs.ip6e_hbh) {
 860                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 861                 u_int32_t dummy; /* XXX unused */
 862                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 863
 864 #ifdef DIAGNOSTIC
 865                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 866                         panic("ip6e_hbh is not contiguous");
 867 #endif
 868                 /*
 869                  *  XXX: if we have to send an ICMPv6 error to the sender,
 870                  *       we need the M_LOOP flag since icmp6_error() expects
 871                  *       the IPv6 and the hop-by-hop options header are
 872                  *       contiguous unless the flag is set.
 873                  */
 874                 m->m_flags |= M_LOOP;
 875                 m->m_pkthdr.rcvif = ifp;
 876                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 877                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 878                     &dummy, &plen) < 0) {
 879                         /* m was already freed at this point */
 880                         error = EINVAL;/* better error? */
 881                         goto done;
 882                 }
 883                 m->m_flags &= ~M_LOOP; /* XXX */
 884                 m->m_pkthdr.rcvif = NULL;
 885         }
 886
 887         /* Jump over all PFIL processing if hooks are not active. */
 888         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
 889                 goto passout;
 890
 891         odst = ip6->ip6_dst;
 892         /* Run through list of hooks for output packets. */
 893         switch (pfil_run_hooks(V_inet6_pfil_head, &m, ifp, PFIL_OUT, inp)) {
 894         case PFIL_PASS:
 895                 ip6 = mtod(m, struct ip6_hdr *);
 896                 break;
 897         case PFIL_DROPPED:
 898                 error = EPERM;
 899                 /* FALLTHROUGH */
 900         case PFIL_CONSUMED:
 901                 goto done;
 902         }
 903
 904         needfiblookup = 0;
 905         /* See if destination IP address was changed by packet filter. */
 906         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
 907                 m->m_flags |= M_SKIP_FIREWALL;
 908                 /* If destination is now ourself drop to ip6_input(). */
 909                 if (in6_localip(&ip6->ip6_dst)) {
 910                         m->m_flags |= M_FASTFWD_OURS;
 911                         if (m->m_pkthdr.rcvif == NULL)
 912                                 m->m_pkthdr.rcvif = V_loif;
 913                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 914                                 m->m_pkthdr.csum_flags |=
 915                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 916                                 m->m_pkthdr.csum_data = 0xffff;
 917                         }
 918 #ifdef SCTP
 919                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 920                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 921 #endif
 922                         error = netisr_queue(NETISR_IPV6, m);
 923                         goto done;
 924                 } else {
 925                         RO_INVALIDATE_CACHE(ro);
 926                         needfiblookup = 1; /* Redo the routing table lookup. */
 927                 }
 928         }
 929         /* See if fib was changed by packet filter. */
 930         if (fibnum != M_GETFIB(m)) {
 931                 m->m_flags |= M_SKIP_FIREWALL;
 932                 fibnum = M_GETFIB(m);
 933                 RO_INVALIDATE_CACHE(ro);
 934                 needfiblookup = 1;
 935         }
 936         if (needfiblookup)
 937                 goto again;
 938
 939         /* See if local, if yes, send it to netisr. */
 940         if (m->m_flags & M_FASTFWD_OURS) {
 941                 if (m->m_pkthdr.rcvif == NULL)
 942                         m->m_pkthdr.rcvif = V_loif;
 943                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 944                         m->m_pkthdr.csum_flags |=
 945                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 946                         m->m_pkthdr.csum_data = 0xffff;
 947                 }
 948 #ifdef SCTP
 949                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 950                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 951 #endif
 952                 error = netisr_queue(NETISR_IPV6, m);
 953                 goto done;
 954         }
 955         /* Or forward to some other address? */
 956         if ((m->m_flags & M_IP6_NEXTHOP) &&
 957             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 958                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 959                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
 960                 m->m_flags |= M_SKIP_FIREWALL;
 961                 m->m_flags &= ~M_IP6_NEXTHOP;
 962                 m_tag_delete(m, fwd_tag);
 963                 goto again;
 964         }
 965
 966 passout:
 967         /*
 968          * Send the packet to the outgoing interface.
 969          * If necessary, do IPv6 fragmentation before sending.
 970          *
 971          * the logic here is rather complex:
 972          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 973          * 1-a: send as is if tlen <= path mtu
 974          * 1-b: fragment if tlen > path mtu
 975          *
 976          * 2: if user asks us not to fragment (dontfrag == 1)
 977          * 2-a: send as is if tlen <= interface mtu
 978          * 2-b: error if tlen > interface mtu
 979          *
 980          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 981          *      always fragment
 982          *
 983          * 4: if dontfrag == 1 && alwaysfrag == 1
 984          *      error, as we cannot handle this conflicting request
 985          */
 986         sw_csum = m->m_pkthdr.csum_flags;
 987         if (!hdrsplit) {
 988                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
 989                 sw_csum &= ~ifp->if_hwassist;
 990         } else
 991                 tso = 0;
 992         /*
 993          * If we added extension headers, we will not do TSO and calculate the
 994          * checksums ourselves for now.
 995          * XXX-BZ  Need a framework to know when the NIC can handle it, even
 996          * with ext. hdrs.
 997          */
 998         if (sw_csum & CSUM_DELAY_DATA_IPV6) {
 999                 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
1000                 m = mb_unmapped_to_ext(m);
1001                 if (m == NULL) {
1002                         error = ENOBUFS;
1003                         IP6STAT_INC(ip6s_odropped);
1004                         goto bad;
1005                 }
1006                 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
1007         } else if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {
1008                 m = mb_unmapped_to_ext(m);
1009                 if (m == NULL) {
1010                         error = ENOBUFS;
1011                         IP6STAT_INC(ip6s_odropped);
1012                         goto bad;
1013                 }
1014         }
1015 #ifdef SCTP
1016         if (sw_csum & CSUM_SCTP_IPV6) {
1017                 sw_csum &= ~CSUM_SCTP_IPV6;
1018                 m = mb_unmapped_to_ext(m);
1019                 if (m == NULL) {
1020                         error = ENOBUFS;
1021                         IP6STAT_INC(ip6s_odropped);
1022                         goto bad;
1023                 }
1024                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
1025         }
1026 #endif
1027         m->m_pkthdr.csum_flags &= ifp->if_hwassist;
1028         tlen = m->m_pkthdr.len;
1029
1030         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1031                 dontfrag = 1;
1032         else
1033                 dontfrag = 0;
1034         if (dontfrag && alwaysfrag) {   /* case 4 */
1035                 /* conflicting request - can't transmit */
1036                 error = EMSGSIZE;
1037                 goto bad;
1038         }
1039         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* case 2-b */
1040                 /*
1041                  * Even if the DONTFRAG option is specified, we cannot send the
1042                  * packet when the data length is larger than the MTU of the
1043                  * outgoing interface.
1044                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1045                  * application wanted to know the MTU value. Also return an
1046                  * error code (this is not described in the API spec).
1047                  */
1048                 if (inp != NULL)
1049                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1050                 error = EMSGSIZE;
1051                 goto bad;
1052         }
1053
1054         /*
1055          * transmit packet without fragmentation
1056          */
1057         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
1058                 struct in6_ifaddr *ia6;
1059
1060                 ip6 = mtod(m, struct ip6_hdr *);
1061                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1062                 if (ia6) {
1063                         /* Record statistics for this interface address. */
1064                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1065                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1066                             m->m_pkthdr.len);
1067                         ifa_free(&ia6->ia_ifa);
1068                 }
1069                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro);
1070                 goto done;
1071         }
1072
1073         /*
1074          * try to fragment the packet.  case 1-b and 3
1075          */
1076         if (mtu < IPV6_MMTU) {
1077                 /* path MTU cannot be less than IPV6_MMTU */
1078                 error = EMSGSIZE;
1079                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1080                 goto bad;
1081         } else if (ip6->ip6_plen == 0) {
1082                 /* jumbo payload cannot be fragmented */
1083                 error = EMSGSIZE;
1084                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1085                 goto bad;
1086         } else {
1087                 u_char nextproto;
1088
1089                 /*
1090                  * Too large for the destination or interface;
1091                  * fragment if possible.
1092                  * Must be able to put at least 8 bytes per fragment.
1093                  */
1094                 hlen = unfragpartlen;
1095                 if (mtu > IPV6_MAXPACKET)
1096                         mtu = IPV6_MAXPACKET;
1097
1098                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
1099                 if (len < 8) {
1100                         error = EMSGSIZE;
1101                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1102                         goto bad;
1103                 }
1104
1105                 /*
1106                  * If the interface will not calculate checksums on
1107                  * fragmented packets, then do it here.
1108                  * XXX-BZ handle the hw offloading case.  Need flags.
1109                  */
1110                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1111                         m = mb_unmapped_to_ext(m);
1112                         if (m == NULL) {
1113                                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1114                                 error = ENOBUFS;
1115                                 goto bad;
1116                         }
1117                         in6_delayed_cksum(m, plen, hlen);
1118                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
1119                 }
1120 #ifdef SCTP
1121                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
1122                         m = mb_unmapped_to_ext(m);
1123                         if (m == NULL) {
1124                                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1125                                 error = ENOBUFS;
1126                                 goto bad;
1127                         }
1128                         sctp_delayed_cksum(m, hlen);
1129                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
1130                 }
1131 #endif
1132                 /*
1133                  * Change the next header field of the last header in the
1134                  * unfragmentable part.
1135                  */
1136                 if (exthdrs.ip6e_rthdr) {
1137                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1138                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1139                 } else if (exthdrs.ip6e_dest1) {
1140                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1141                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1142                 } else if (exthdrs.ip6e_hbh) {
1143                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1144                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1145                 } else {
1146                         nextproto = ip6->ip6_nxt;
1147                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1148                 }
1149
1150                 /*
1151                  * Loop through length of segment after first fragment,
1152                  * make new header and copy data of each part and link onto
1153                  * chain.
1154                  */
1155                 m0 = m;
1156                 id = htonl(ip6_randomid());
1157                 if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
1158                         goto sendorfree;
1159
1160                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1161         }
1162
1163         /*
1164          * Remove leading garbages.
1165          */
1166 sendorfree:
1167         m = m0->m_nextpkt;
1168         m0->m_nextpkt = 0;
1169         m_freem(m0);
1170         for (; m; m = m0) {
1171                 m0 = m->m_nextpkt;
1172                 m->m_nextpkt = 0;
1173                 if (error == 0) {
1174                         /* Record statistics for this interface address. */
1175                         if (ia) {
1176                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1177                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1178                                     m->m_pkthdr.len);
1179                         }
1180                         error = ip6_output_send(inp, ifp, origifp, m, dst, ro);
1181                 } else
1182                         m_freem(m);
1183         }
1184
1185         if (error == 0)
1186                 IP6STAT_INC(ip6s_fragmented);
1187
1188 done:
1189         if (ro == &ip6route)
1190                 RO_RTFREE(ro);
1191         return (error);
1192
1193 freehdrs:
1194         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1195         m_freem(exthdrs.ip6e_dest1);
1196         m_freem(exthdrs.ip6e_rthdr);
1197         m_freem(exthdrs.ip6e_dest2);
1198         /* FALLTHROUGH */
1199 bad:
1200         if (m)
1201                 m_freem(m);
1202         goto done;
1203 }
1204
1205 static int
1206 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1207 {
1208         struct mbuf *m;
1209
1210         if (hlen > MCLBYTES)
1211                 return (ENOBUFS); /* XXX */
1212
1213         if (hlen > MLEN)
1214                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1215         else
1216                 m = m_get(M_NOWAIT, MT_DATA);
1217         if (m == NULL)
1218                 return (ENOBUFS);
1219         m->m_len = hlen;
1220         if (hdr)
1221                 bcopy(hdr, mtod(m, caddr_t), hlen);
1222
1223         *mp = m;
1224         return (0);
1225 }
1226
1227 /*
1228  * Insert jumbo payload option.
1229  */
1230 static int
1231 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1232 {
1233         struct mbuf *mopt;
1234         u_char *optbuf;
1235         u_int32_t v;
1236
1237 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1238
1239         /*
1240          * If there is no hop-by-hop options header, allocate new one.
1241          * If there is one but it doesn't have enough space to store the
1242          * jumbo payload option, allocate a cluster to store the whole options.
1243          * Otherwise, use it to store the options.
1244          */
1245         if (exthdrs->ip6e_hbh == NULL) {
1246                 mopt = m_get(M_NOWAIT, MT_DATA);
1247                 if (mopt == NULL)
1248                         return (ENOBUFS);
1249                 mopt->m_len = JUMBOOPTLEN;
1250                 optbuf = mtod(mopt, u_char *);
1251                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1252                 exthdrs->ip6e_hbh = mopt;
1253         } else {
1254                 struct ip6_hbh *hbh;
1255
1256                 mopt = exthdrs->ip6e_hbh;
1257                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1258                         /*
1259                          * XXX assumption:
1260                          * - exthdrs->ip6e_hbh is not referenced from places
1261                          *   other than exthdrs.
1262                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1263                          */
1264                         int oldoptlen = mopt->m_len;
1265                         struct mbuf *n;
1266
1267                         /*
1268                          * XXX: give up if the whole (new) hbh header does
1269                          * not fit even in an mbuf cluster.
1270                          */
1271                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1272                                 return (ENOBUFS);
1273
1274                         /*
1275                          * As a consequence, we must always prepare a cluster
1276                          * at this point.
1277                          */
1278                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1279                         if (n == NULL)
1280                                 return (ENOBUFS);
1281                         n->m_len = oldoptlen + JUMBOOPTLEN;
1282                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1283                             oldoptlen);
1284                         optbuf = mtod(n, caddr_t) + oldoptlen;
1285                         m_freem(mopt);
1286                         mopt = exthdrs->ip6e_hbh = n;
1287                 } else {
1288                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1289                         mopt->m_len += JUMBOOPTLEN;
1290                 }
1291                 optbuf[0] = IP6OPT_PADN;
1292                 optbuf[1] = 1;
1293
1294                 /*
1295                  * Adjust the header length according to the pad and
1296                  * the jumbo payload option.
1297                  */
1298                 hbh = mtod(mopt, struct ip6_hbh *);
1299                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1300         }
1301
1302         /* fill in the option. */
1303         optbuf[2] = IP6OPT_JUMBO;
1304         optbuf[3] = 4;
1305         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1306         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1307
1308         /* finally, adjust the packet header length */
1309         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1310
1311         return (0);
1312 #undef JUMBOOPTLEN
1313 }
1314
1315 /*
1316  * Insert fragment header and copy unfragmentable header portions.
1317  */
1318 static int
1319 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1320     struct ip6_frag **frghdrp)
1321 {
1322         struct mbuf *n, *mlast;
1323
1324         if (hlen > sizeof(struct ip6_hdr)) {
1325                 n = m_copym(m0, sizeof(struct ip6_hdr),
1326                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1327                 if (n == NULL)
1328                         return (ENOBUFS);
1329                 m->m_next = n;
1330         } else
1331                 n = m;
1332
1333         /* Search for the last mbuf of unfragmentable part. */
1334         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1335                 ;
1336
1337         if (M_WRITABLE(mlast) &&
1338             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1339                 /* use the trailing space of the last mbuf for the fragment hdr */
1340                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1341                     mlast->m_len);
1342                 mlast->m_len += sizeof(struct ip6_frag);
1343                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1344         } else {
1345                 /* allocate a new mbuf for the fragment header */
1346                 struct mbuf *mfrg;
1347
1348                 mfrg = m_get(M_NOWAIT, MT_DATA);
1349                 if (mfrg == NULL)
1350                         return (ENOBUFS);
1351                 mfrg->m_len = sizeof(struct ip6_frag);
1352                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1353                 mlast->m_next = mfrg;
1354         }
1355
1356         return (0);
1357 }
1358
1359 /*
1360  * Calculates IPv6 path mtu for destination @dst.
1361  * Resulting MTU is stored in @mtup.
1362  *
1363  * Returns 0 on success.
1364  */
1365 static int
1366 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1367 {
1368         struct nhop6_extended nh6;
1369         struct in6_addr kdst;
1370         uint32_t scopeid;
1371         struct ifnet *ifp;
1372         u_long mtu;
1373         int error;
1374
1375         in6_splitscope(dst, &kdst, &scopeid);
1376         if (fib6_lookup_nh_ext(fibnum, &kdst, scopeid, NHR_REF, 0, &nh6) != 0)
1377                 return (EHOSTUNREACH);
1378
1379         ifp = nh6.nh_ifp;
1380         mtu = nh6.nh_mtu;
1381
1382         error = ip6_calcmtu(ifp, dst, mtu, mtup, NULL, 0);
1383         fib6_free_nh_ext(fibnum, &nh6);
1384
1385         return (error);
1386 }
1387
1388 /*
1389  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1390  * and cached data in @ro_pmtu.
1391  * MTU from (successful) route lookup is saved (along with dst)
1392  * inside @ro_pmtu to avoid subsequent route lookups after packet
1393  * filter processing.
1394  *
1395  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1396  * Returns 0 on success.
1397  */
1398 static int
1399 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1400     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1401     int *alwaysfragp, u_int fibnum, u_int proto)
1402 {
1403         struct nhop6_basic nh6;
1404         struct in6_addr kdst;
1405         uint32_t scopeid;
1406         struct sockaddr_in6 *sa6_dst;
1407         u_long mtu;
1408
1409         mtu = 0;
1410         if (do_lookup) {
1411
1412                 /*
1413                  * Here ro_pmtu has final destination address, while
1414                  * ro might represent immediate destination.
1415                  * Use ro_pmtu destination since mtu might differ.
1416                  */
1417                 sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1418                 if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1419                         ro_pmtu->ro_mtu = 0;
1420
1421                 if (ro_pmtu->ro_mtu == 0) {
1422                         bzero(sa6_dst, sizeof(*sa6_dst));
1423                         sa6_dst->sin6_family = AF_INET6;
1424                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1425                         sa6_dst->sin6_addr = *dst;
1426
1427                         in6_splitscope(dst, &kdst, &scopeid);
1428                         if (fib6_lookup_nh_basic(fibnum, &kdst, scopeid, 0, 0,
1429                             &nh6) == 0)
1430                                 ro_pmtu->ro_mtu = nh6.nh_mtu;
1431                 }
1432
1433                 mtu = ro_pmtu->ro_mtu;
1434         }
1435
1436         if (ro_pmtu->ro_rt)
1437                 mtu = ro_pmtu->ro_rt->rt_mtu;
1438
1439         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1440 }
1441
1442 /*
1443  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1444  * hostcache data for @dst.
1445  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1446  *
1447  * Returns 0 on success.
1448  */
1449 static int
1450 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1451     u_long *mtup, int *alwaysfragp, u_int proto)
1452 {
1453         u_long mtu = 0;
1454         int alwaysfrag = 0;
1455         int error = 0;
1456
1457         if (rt_mtu > 0) {
1458                 u_int32_t ifmtu;
1459                 struct in_conninfo inc;
1460
1461                 bzero(&inc, sizeof(inc));
1462                 inc.inc_flags |= INC_ISIPV6;
1463                 inc.inc6_faddr = *dst;
1464
1465                 ifmtu = IN6_LINKMTU(ifp);
1466
1467                 /* TCP is known to react to pmtu changes so skip hc */
1468                 if (proto != IPPROTO_TCP)
1469                         mtu = tcp_hc_getmtu(&inc);
1470
1471                 if (mtu)
1472                         mtu = min(mtu, rt_mtu);
1473                 else
1474                         mtu = rt_mtu;
1475                 if (mtu == 0)
1476                         mtu = ifmtu;
1477                 else if (mtu < IPV6_MMTU) {
1478                         /*
1479                          * RFC2460 section 5, last paragraph:
1480                          * if we record ICMPv6 too big message with
1481                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1482                          * or smaller, with framgent header attached.
1483                          * (fragment header is needed regardless from the
1484                          * packet size, for translators to identify packets)
1485                          */
1486                         alwaysfrag = 1;
1487                         mtu = IPV6_MMTU;
1488                 }
1489         } else if (ifp) {
1490                 mtu = IN6_LINKMTU(ifp);
1491         } else
1492                 error = EHOSTUNREACH; /* XXX */
1493
1494         *mtup = mtu;
1495         if (alwaysfragp)
1496                 *alwaysfragp = alwaysfrag;
1497         return (error);
1498 }
1499
1500 /*
1501  * IP6 socket option processing.
1502  */
1503 int
1504 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1505 {
1506         int optdatalen, uproto;
1507         void *optdata;
1508         struct inpcb *inp = sotoinpcb(so);
1509         int error, optval;
1510         int level, op, optname;
1511         int optlen;
1512         struct thread *td;
1513 #ifdef  RSS
1514         uint32_t rss_bucket;
1515         int retval;
1516 #endif
1517
1518 /*
1519  * Don't use more than a quarter of mbuf clusters.  N.B.:
1520  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1521  * on LP64 architectures, so cast to u_long to avoid undefined
1522  * behavior.  ILP32 architectures cannot have nmbclusters
1523  * large enough to overflow for other reasons.
1524  */
1525 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1526
1527         level = sopt->sopt_level;
1528         op = sopt->sopt_dir;
1529         optname = sopt->sopt_name;
1530         optlen = sopt->sopt_valsize;
1531         td = sopt->sopt_td;
1532         error = 0;
1533         optval = 0;
1534         uproto = (int)so->so_proto->pr_protocol;
1535
1536         if (level != IPPROTO_IPV6) {
1537                 error = EINVAL;
1538
1539                 if (sopt->sopt_level == SOL_SOCKET &&
1540                     sopt->sopt_dir == SOPT_SET) {
1541                         switch (sopt->sopt_name) {
1542                         case SO_REUSEADDR:
1543                                 INP_WLOCK(inp);
1544                                 if ((so->so_options & SO_REUSEADDR) != 0)
1545                                         inp->inp_flags2 |= INP_REUSEADDR;
1546                                 else
1547                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1548                                 INP_WUNLOCK(inp);
1549                                 error = 0;
1550                                 break;
1551                         case SO_REUSEPORT:
1552                                 INP_WLOCK(inp);
1553                                 if ((so->so_options & SO_REUSEPORT) != 0)
1554                                         inp->inp_flags2 |= INP_REUSEPORT;
1555                                 else
1556                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1557                                 INP_WUNLOCK(inp);
1558                                 error = 0;
1559                                 break;
1560                         case SO_REUSEPORT_LB:
1561                                 INP_WLOCK(inp);
1562                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1563                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1564                                 else
1565                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1566                                 INP_WUNLOCK(inp);
1567                                 error = 0;
1568                                 break;
1569                         case SO_SETFIB:
1570                                 INP_WLOCK(inp);
1571                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1572                                 INP_WUNLOCK(inp);
1573                                 error = 0;
1574                                 break;
1575                         case SO_MAX_PACING_RATE:
1576 #ifdef RATELIMIT
1577                                 INP_WLOCK(inp);
1578                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1579                                 INP_WUNLOCK(inp);
1580                                 error = 0;
1581 #else
1582                                 error = EOPNOTSUPP;
1583 #endif
1584                                 break;
1585                         default:
1586                                 break;
1587                         }
1588                 }
1589         } else {                /* level == IPPROTO_IPV6 */
1590                 switch (op) {
1591
1592                 case SOPT_SET:
1593                         switch (optname) {
1594                         case IPV6_2292PKTOPTIONS:
1595 #ifdef IPV6_PKTOPTIONS
1596                         case IPV6_PKTOPTIONS:
1597 #endif
1598                         {
1599                                 struct mbuf *m;
1600
1601                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1602                                         printf("ip6_ctloutput: mbuf limit hit\n");
1603                                         error = ENOBUFS;
1604                                         break;
1605                                 }
1606
1607                                 error = soopt_getm(sopt, &m); /* XXX */
1608                                 if (error != 0)
1609                                         break;
1610                                 error = soopt_mcopyin(sopt, m); /* XXX */
1611                                 if (error != 0)
1612                                         break;
1613                                 error = ip6_pcbopts(&inp->in6p_outputopts,
1614                                                     m, so, sopt);
1615                                 m_freem(m); /* XXX */
1616                                 break;
1617                         }
1618
1619                         /*
1620                          * Use of some Hop-by-Hop options or some
1621                          * Destination options, might require special
1622                          * privilege.  That is, normal applications
1623                          * (without special privilege) might be forbidden
1624                          * from setting certain options in outgoing packets,
1625                          * and might never see certain options in received
1626                          * packets. [RFC 2292 Section 6]
1627                          * KAME specific note:
1628                          *  KAME prevents non-privileged users from sending or
1629                          *  receiving ANY hbh/dst options in order to avoid
1630                          *  overhead of parsing options in the kernel.
1631                          */
1632                         case IPV6_RECVHOPOPTS:
1633                         case IPV6_RECVDSTOPTS:
1634                         case IPV6_RECVRTHDRDSTOPTS:
1635                                 if (td != NULL) {
1636                                         error = priv_check(td,
1637                                             PRIV_NETINET_SETHDROPTS);
1638                                         if (error)
1639                                                 break;
1640                                 }
1641                                 /* FALLTHROUGH */
1642                         case IPV6_UNICAST_HOPS:
1643                         case IPV6_HOPLIMIT:
1644
1645                         case IPV6_RECVPKTINFO:
1646                         case IPV6_RECVHOPLIMIT:
1647                         case IPV6_RECVRTHDR:
1648                         case IPV6_RECVPATHMTU:
1649                         case IPV6_RECVTCLASS:
1650                         case IPV6_RECVFLOWID:
1651 #ifdef  RSS
1652                         case IPV6_RECVRSSBUCKETID:
1653 #endif
1654                         case IPV6_V6ONLY:
1655                         case IPV6_AUTOFLOWLABEL:
1656                         case IPV6_ORIGDSTADDR:
1657                         case IPV6_BINDANY:
1658                         case IPV6_BINDMULTI:
1659 #ifdef  RSS
1660                         case IPV6_RSS_LISTEN_BUCKET:
1661 #endif
1662                                 if (optname == IPV6_BINDANY && td != NULL) {
1663                                         error = priv_check(td,
1664                                             PRIV_NETINET_BINDANY);
1665                                         if (error)
1666                                                 break;
1667                                 }
1668
1669                                 if (optlen != sizeof(int)) {
1670                                         error = EINVAL;
1671                                         break;
1672                                 }
1673                                 error = sooptcopyin(sopt, &optval,
1674                                         sizeof optval, sizeof optval);
1675                                 if (error)
1676                                         break;
1677                                 switch (optname) {
1678
1679                                 case IPV6_UNICAST_HOPS:
1680                                         if (optval < -1 || optval >= 256)
1681                                                 error = EINVAL;
1682                                         else {
1683                                                 /* -1 = kernel default */
1684                                                 inp->in6p_hops = optval;
1685                                                 if ((inp->inp_vflag &
1686                                                      INP_IPV4) != 0)
1687                                                         inp->inp_ip_ttl = optval;
1688                                         }
1689                                         break;
1690 #define OPTSET(bit) \
1691 do { \
1692         INP_WLOCK(inp); \
1693         if (optval) \
1694                 inp->inp_flags |= (bit); \
1695         else \
1696                 inp->inp_flags &= ~(bit); \
1697         INP_WUNLOCK(inp); \
1698 } while (/*CONSTCOND*/ 0)
1699 #define OPTSET2292(bit) \
1700 do { \
1701         INP_WLOCK(inp); \
1702         inp->inp_flags |= IN6P_RFC2292; \
1703         if (optval) \
1704                 inp->inp_flags |= (bit); \
1705         else \
1706                 inp->inp_flags &= ~(bit); \
1707         INP_WUNLOCK(inp); \
1708 } while (/*CONSTCOND*/ 0)
1709 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1710
1711 #define OPTSET2_N(bit, val) do {                                        \
1712         if (val)                                                        \
1713                 inp->inp_flags2 |= bit;                                 \
1714         else                                                            \
1715                 inp->inp_flags2 &= ~bit;                                \
1716 } while (0)
1717 #define OPTSET2(bit, val) do {                                          \
1718         INP_WLOCK(inp);                                                 \
1719         OPTSET2_N(bit, val);                                            \
1720         INP_WUNLOCK(inp);                                               \
1721 } while (0)
1722 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1723 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1724 do {                                                                    \
1725         INP_WLOCK(inp);                                                 \
1726         if (OPTBIT(IN6P_RFC2292)) {                                     \
1727                 error = EINVAL;                                         \
1728         } else {                                                        \
1729                 if (optval)                                             \
1730                         inp->inp_flags |= (bit);                        \
1731                 else                                                    \
1732                         inp->inp_flags &= ~(bit);                       \
1733         }                                                               \
1734         INP_WUNLOCK(inp);                                               \
1735 } while (/*CONSTCOND*/ 0)
1736
1737                                 case IPV6_RECVPKTINFO:
1738                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1739                                         break;
1740
1741                                 case IPV6_HOPLIMIT:
1742                                 {
1743                                         struct ip6_pktopts **optp;
1744
1745                                         /* cannot mix with RFC2292 */
1746                                         if (OPTBIT(IN6P_RFC2292)) {
1747                                                 error = EINVAL;
1748                                                 break;
1749                                         }
1750                                         INP_WLOCK(inp);
1751                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1752                                                 INP_WUNLOCK(inp);
1753                                                 return (ECONNRESET);
1754                                         }
1755                                         optp = &inp->in6p_outputopts;
1756                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1757                                             (u_char *)&optval, sizeof(optval),
1758                                             optp, (td != NULL) ? td->td_ucred :
1759                                             NULL, uproto);
1760                                         INP_WUNLOCK(inp);
1761                                         break;
1762                                 }
1763
1764                                 case IPV6_RECVHOPLIMIT:
1765                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1766                                         break;
1767
1768                                 case IPV6_RECVHOPOPTS:
1769                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1770                                         break;
1771
1772                                 case IPV6_RECVDSTOPTS:
1773                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1774                                         break;
1775
1776                                 case IPV6_RECVRTHDRDSTOPTS:
1777                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1778                                         break;
1779
1780                                 case IPV6_RECVRTHDR:
1781                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1782                                         break;
1783
1784                                 case IPV6_RECVPATHMTU:
1785                                         /*
1786                                          * We ignore this option for TCP
1787                                          * sockets.
1788                                          * (RFC3542 leaves this case
1789                                          * unspecified.)
1790                                          */
1791                                         if (uproto != IPPROTO_TCP)
1792                                                 OPTSET(IN6P_MTU);
1793                                         break;
1794
1795                                 case IPV6_RECVFLOWID:
1796                                         OPTSET2(INP_RECVFLOWID, optval);
1797                                         break;
1798
1799 #ifdef  RSS
1800                                 case IPV6_RECVRSSBUCKETID:
1801                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1802                                         break;
1803 #endif
1804
1805                                 case IPV6_V6ONLY:
1806                                         /*
1807                                          * make setsockopt(IPV6_V6ONLY)
1808                                          * available only prior to bind(2).
1809                                          * see ipng mailing list, Jun 22 2001.
1810                                          */
1811                                         if (inp->inp_lport ||
1812                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1813                                                 error = EINVAL;
1814                                                 break;
1815                                         }
1816                                         OPTSET(IN6P_IPV6_V6ONLY);
1817                                         if (optval)
1818                                                 inp->inp_vflag &= ~INP_IPV4;
1819                                         else
1820                                                 inp->inp_vflag |= INP_IPV4;
1821                                         break;
1822                                 case IPV6_RECVTCLASS:
1823                                         /* cannot mix with RFC2292 XXX */
1824                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1825                                         break;
1826                                 case IPV6_AUTOFLOWLABEL:
1827                                         OPTSET(IN6P_AUTOFLOWLABEL);
1828                                         break;
1829
1830                                 case IPV6_ORIGDSTADDR:
1831                                         OPTSET2(INP_ORIGDSTADDR, optval);
1832                                         break;
1833                                 case IPV6_BINDANY:
1834                                         OPTSET(INP_BINDANY);
1835                                         break;
1836
1837                                 case IPV6_BINDMULTI:
1838                                         OPTSET2(INP_BINDMULTI, optval);
1839                                         break;
1840 #ifdef  RSS
1841                                 case IPV6_RSS_LISTEN_BUCKET:
1842                                         if ((optval >= 0) &&
1843                                             (optval < rss_getnumbuckets())) {
1844                                                 INP_WLOCK(inp);
1845                                                 inp->inp_rss_listen_bucket = optval;
1846                                                 OPTSET2_N(INP_RSS_BUCKET_SET, 1);
1847                                                 INP_WUNLOCK(inp);
1848                                         } else {
1849                                                 error = EINVAL;
1850                                         }
1851                                         break;
1852 #endif
1853                                 }
1854                                 break;
1855
1856                         case IPV6_TCLASS:
1857                         case IPV6_DONTFRAG:
1858                         case IPV6_USE_MIN_MTU:
1859                         case IPV6_PREFER_TEMPADDR:
1860                                 if (optlen != sizeof(optval)) {
1861                                         error = EINVAL;
1862                                         break;
1863                                 }
1864                                 error = sooptcopyin(sopt, &optval,
1865                                         sizeof optval, sizeof optval);
1866                                 if (error)
1867                                         break;
1868                                 {
1869                                         struct ip6_pktopts **optp;
1870                                         INP_WLOCK(inp);
1871                                         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1872                                                 INP_WUNLOCK(inp);
1873                                                 return (ECONNRESET);
1874                                         }
1875                                         optp = &inp->in6p_outputopts;
1876                                         error = ip6_pcbopt(optname,
1877                                             (u_char *)&optval, sizeof(optval),
1878                                             optp, (td != NULL) ? td->td_ucred :
1879                                             NULL, uproto);
1880                                         INP_WUNLOCK(inp);
1881                                         break;
1882                                 }
1883
1884                         case IPV6_2292PKTINFO:
1885                         case IPV6_2292HOPLIMIT:
1886                         case IPV6_2292HOPOPTS:
1887                         case IPV6_2292DSTOPTS:
1888                         case IPV6_2292RTHDR:
1889                                 /* RFC 2292 */
1890                                 if (optlen != sizeof(int)) {
1891                                         error = EINVAL;
1892                                         break;
1893                                 }
1894                                 error = sooptcopyin(sopt, &optval,
1895                                         sizeof optval, sizeof optval);
1896                                 if (error)
1897                                         break;
1898                                 switch (optname) {
1899                                 case IPV6_2292PKTINFO:
1900                                         OPTSET2292(IN6P_PKTINFO);
1901                                         break;
1902                                 case IPV6_2292HOPLIMIT:
1903                                         OPTSET2292(IN6P_HOPLIMIT);
1904                                         break;
1905                                 case IPV6_2292HOPOPTS:
1906                                         /*
1907                                          * Check super-user privilege.
1908                                          * See comments for IPV6_RECVHOPOPTS.
1909                                          */
1910                                         if (td != NULL) {
1911                                                 error = priv_check(td,
1912                                                     PRIV_NETINET_SETHDROPTS);
1913                                                 if (error)
1914                                                         return (error);
1915                                         }
1916                                         OPTSET2292(IN6P_HOPOPTS);
1917                                         break;
1918                                 case IPV6_2292DSTOPTS:
1919                                         if (td != NULL) {
1920                                                 error = priv_check(td,
1921                                                     PRIV_NETINET_SETHDROPTS);
1922                                                 if (error)
1923                                                         return (error);
1924                                         }
1925                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1926                                         break;
1927                                 case IPV6_2292RTHDR:
1928                                         OPTSET2292(IN6P_RTHDR);
1929                                         break;
1930                                 }
1931                                 break;
1932                         case IPV6_PKTINFO:
1933                         case IPV6_HOPOPTS:
1934                         case IPV6_RTHDR:
1935                         case IPV6_DSTOPTS:
1936                         case IPV6_RTHDRDSTOPTS:
1937                         case IPV6_NEXTHOP:
1938                         {
1939                                 /* new advanced API (RFC3542) */
1940                                 u_char *optbuf;
1941                                 u_char optbuf_storage[MCLBYTES];
1942                                 int optlen;
1943                                 struct ip6_pktopts **optp;
1944
1945                                 /* cannot mix with RFC2292 */
1946                                 if (OPTBIT(IN6P_RFC2292)) {
1947                                         error = EINVAL;
1948                                         break;
1949                                 }
1950
1951                                 /*
1952                                  * We only ensure valsize is not too large
1953                                  * here.  Further validation will be done
1954                                  * later.
1955                                  */
1956                                 error = sooptcopyin(sopt, optbuf_storage,
1957                                     sizeof(optbuf_storage), 0);
1958                                 if (error)
1959                                         break;
1960                                 optlen = sopt->sopt_valsize;
1961                                 optbuf = optbuf_storage;
1962                                 INP_WLOCK(inp);
1963                                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1964                                         INP_WUNLOCK(inp);
1965                                         return (ECONNRESET);
1966                                 }
1967                                 optp = &inp->in6p_outputopts;
1968                                 error = ip6_pcbopt(optname, optbuf, optlen,
1969                                     optp, (td != NULL) ? td->td_ucred : NULL,
1970                                     uproto);
1971                                 INP_WUNLOCK(inp);
1972                                 break;
1973                         }
1974 #undef OPTSET
1975
1976                         case IPV6_MULTICAST_IF:
1977                         case IPV6_MULTICAST_HOPS:
1978                         case IPV6_MULTICAST_LOOP:
1979                         case IPV6_JOIN_GROUP:
1980                         case IPV6_LEAVE_GROUP:
1981                         case IPV6_MSFILTER:
1982                         case MCAST_BLOCK_SOURCE:
1983                         case MCAST_UNBLOCK_SOURCE:
1984                         case MCAST_JOIN_GROUP:
1985                         case MCAST_LEAVE_GROUP:
1986                         case MCAST_JOIN_SOURCE_GROUP:
1987                         case MCAST_LEAVE_SOURCE_GROUP:
1988                                 error = ip6_setmoptions(inp, sopt);
1989                                 break;
1990
1991                         case IPV6_PORTRANGE:
1992                                 error = sooptcopyin(sopt, &optval,
1993                                     sizeof optval, sizeof optval);
1994                                 if (error)
1995                                         break;
1996
1997                                 INP_WLOCK(inp);
1998                                 switch (optval) {
1999                                 case IPV6_PORTRANGE_DEFAULT:
2000                                         inp->inp_flags &= ~(INP_LOWPORT);
2001                                         inp->inp_flags &= ~(INP_HIGHPORT);
2002                                         break;
2003
2004                                 case IPV6_PORTRANGE_HIGH:
2005                                         inp->inp_flags &= ~(INP_LOWPORT);
2006                                         inp->inp_flags |= INP_HIGHPORT;
2007                                         break;
2008
2009                                 case IPV6_PORTRANGE_LOW:
2010                                         inp->inp_flags &= ~(INP_HIGHPORT);
2011                                         inp->inp_flags |= INP_LOWPORT;
2012                                         break;
2013
2014                                 default:
2015                                         error = EINVAL;
2016                                         break;
2017                                 }
2018                                 INP_WUNLOCK(inp);
2019                                 break;
2020
2021 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2022                         case IPV6_IPSEC_POLICY:
2023                                 if (IPSEC_ENABLED(ipv6)) {
2024                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2025                                         break;
2026                                 }
2027                                 /* FALLTHROUGH */
2028 #endif /* IPSEC */
2029
2030                         default:
2031                                 error = ENOPROTOOPT;
2032                                 break;
2033                         }
2034                         break;
2035
2036                 case SOPT_GET:
2037                         switch (optname) {
2038
2039                         case IPV6_2292PKTOPTIONS:
2040 #ifdef IPV6_PKTOPTIONS
2041                         case IPV6_PKTOPTIONS:
2042 #endif
2043                                 /*
2044                                  * RFC3542 (effectively) deprecated the
2045                                  * semantics of the 2292-style pktoptions.
2046                                  * Since it was not reliable in nature (i.e.,
2047                                  * applications had to expect the lack of some
2048                                  * information after all), it would make sense
2049                                  * to simplify this part by always returning
2050                                  * empty data.
2051                                  */
2052                                 sopt->sopt_valsize = 0;
2053                                 break;
2054
2055                         case IPV6_RECVHOPOPTS:
2056                         case IPV6_RECVDSTOPTS:
2057                         case IPV6_RECVRTHDRDSTOPTS:
2058                         case IPV6_UNICAST_HOPS:
2059                         case IPV6_RECVPKTINFO:
2060                         case IPV6_RECVHOPLIMIT:
2061                         case IPV6_RECVRTHDR:
2062                         case IPV6_RECVPATHMTU:
2063
2064                         case IPV6_V6ONLY:
2065                         case IPV6_PORTRANGE:
2066                         case IPV6_RECVTCLASS:
2067                         case IPV6_AUTOFLOWLABEL:
2068                         case IPV6_BINDANY:
2069                         case IPV6_FLOWID:
2070                         case IPV6_FLOWTYPE:
2071                         case IPV6_RECVFLOWID:
2072 #ifdef  RSS
2073                         case IPV6_RSSBUCKETID:
2074                         case IPV6_RECVRSSBUCKETID:
2075 #endif
2076                         case IPV6_BINDMULTI:
2077                                 switch (optname) {
2078
2079                                 case IPV6_RECVHOPOPTS:
2080                                         optval = OPTBIT(IN6P_HOPOPTS);
2081                                         break;
2082
2083                                 case IPV6_RECVDSTOPTS:
2084                                         optval = OPTBIT(IN6P_DSTOPTS);
2085                                         break;
2086
2087                                 case IPV6_RECVRTHDRDSTOPTS:
2088                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2089                                         break;
2090
2091                                 case IPV6_UNICAST_HOPS:
2092                                         optval = inp->in6p_hops;
2093                                         break;
2094
2095                                 case IPV6_RECVPKTINFO:
2096                                         optval = OPTBIT(IN6P_PKTINFO);
2097                                         break;
2098
2099                                 case IPV6_RECVHOPLIMIT:
2100                                         optval = OPTBIT(IN6P_HOPLIMIT);
2101                                         break;
2102
2103                                 case IPV6_RECVRTHDR:
2104                                         optval = OPTBIT(IN6P_RTHDR);
2105                                         break;
2106
2107                                 case IPV6_RECVPATHMTU:
2108                                         optval = OPTBIT(IN6P_MTU);
2109                                         break;
2110
2111                                 case IPV6_V6ONLY:
2112                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2113                                         break;
2114
2115                                 case IPV6_PORTRANGE:
2116                                     {
2117                                         int flags;
2118                                         flags = inp->inp_flags;
2119                                         if (flags & INP_HIGHPORT)
2120                                                 optval = IPV6_PORTRANGE_HIGH;
2121                                         else if (flags & INP_LOWPORT)
2122                                                 optval = IPV6_PORTRANGE_LOW;
2123                                         else
2124                                                 optval = 0;
2125                                         break;
2126                                     }
2127                                 case IPV6_RECVTCLASS:
2128                                         optval = OPTBIT(IN6P_TCLASS);
2129                                         break;
2130
2131                                 case IPV6_AUTOFLOWLABEL:
2132                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2133                                         break;
2134
2135                                 case IPV6_ORIGDSTADDR:
2136                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2137                                         break;
2138
2139                                 case IPV6_BINDANY:
2140                                         optval = OPTBIT(INP_BINDANY);
2141                                         break;
2142
2143                                 case IPV6_FLOWID:
2144                                         optval = inp->inp_flowid;
2145                                         break;
2146
2147                                 case IPV6_FLOWTYPE:
2148                                         optval = inp->inp_flowtype;
2149                                         break;
2150
2151                                 case IPV6_RECVFLOWID:
2152                                         optval = OPTBIT2(INP_RECVFLOWID);
2153                                         break;
2154 #ifdef  RSS
2155                                 case IPV6_RSSBUCKETID:
2156                                         retval =
2157                                             rss_hash2bucket(inp->inp_flowid,
2158                                             inp->inp_flowtype,
2159                                             &rss_bucket);
2160                                         if (retval == 0)
2161                                                 optval = rss_bucket;
2162                                         else
2163                                                 error = EINVAL;
2164                                         break;
2165
2166                                 case IPV6_RECVRSSBUCKETID:
2167                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2168                                         break;
2169 #endif
2170
2171                                 case IPV6_BINDMULTI:
2172                                         optval = OPTBIT2(INP_BINDMULTI);
2173                                         break;
2174
2175                                 }
2176                                 if (error)
2177                                         break;
2178                                 error = sooptcopyout(sopt, &optval,
2179                                         sizeof optval);
2180                                 break;
2181
2182                         case IPV6_PATHMTU:
2183                         {
2184                                 u_long pmtu = 0;
2185                                 struct ip6_mtuinfo mtuinfo;
2186                                 struct in6_addr addr;
2187
2188                                 if (!(so->so_state & SS_ISCONNECTED))
2189                                         return (ENOTCONN);
2190                                 /*
2191                                  * XXX: we dot not consider the case of source
2192                                  * routing, or optional information to specify
2193                                  * the outgoing interface.
2194                                  * Copy faddr out of inp to avoid holding lock
2195                                  * on inp during route lookup.
2196                                  */
2197                                 INP_RLOCK(inp);
2198                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2199                                 INP_RUNLOCK(inp);
2200                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2201                                     &addr, &pmtu);
2202                                 if (error)
2203                                         break;
2204                                 if (pmtu > IPV6_MAXPACKET)
2205                                         pmtu = IPV6_MAXPACKET;
2206
2207                                 bzero(&mtuinfo, sizeof(mtuinfo));
2208                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2209                                 optdata = (void *)&mtuinfo;
2210                                 optdatalen = sizeof(mtuinfo);
2211                                 error = sooptcopyout(sopt, optdata,
2212                                     optdatalen);
2213                                 break;
2214                         }
2215
2216                         case IPV6_2292PKTINFO:
2217                         case IPV6_2292HOPLIMIT:
2218                         case IPV6_2292HOPOPTS:
2219                         case IPV6_2292RTHDR:
2220                         case IPV6_2292DSTOPTS:
2221                                 switch (optname) {
2222                                 case IPV6_2292PKTINFO:
2223                                         optval = OPTBIT(IN6P_PKTINFO);
2224                                         break;
2225                                 case IPV6_2292HOPLIMIT:
2226                                         optval = OPTBIT(IN6P_HOPLIMIT);
2227                                         break;
2228                                 case IPV6_2292HOPOPTS:
2229                                         optval = OPTBIT(IN6P_HOPOPTS);
2230                                         break;
2231                                 case IPV6_2292RTHDR:
2232                                         optval = OPTBIT(IN6P_RTHDR);
2233                                         break;
2234                                 case IPV6_2292DSTOPTS:
2235                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2236                                         break;
2237                                 }
2238                                 error = sooptcopyout(sopt, &optval,
2239                                     sizeof optval);
2240                                 break;
2241                         case IPV6_PKTINFO:
2242                         case IPV6_HOPOPTS:
2243                         case IPV6_RTHDR:
2244                         case IPV6_DSTOPTS:
2245                         case IPV6_RTHDRDSTOPTS:
2246                         case IPV6_NEXTHOP:
2247                         case IPV6_TCLASS:
2248                         case IPV6_DONTFRAG:
2249                         case IPV6_USE_MIN_MTU:
2250                         case IPV6_PREFER_TEMPADDR:
2251                                 error = ip6_getpcbopt(inp, optname, sopt);
2252                                 break;
2253
2254                         case IPV6_MULTICAST_IF:
2255                         case IPV6_MULTICAST_HOPS:
2256                         case IPV6_MULTICAST_LOOP:
2257                         case IPV6_MSFILTER:
2258                                 error = ip6_getmoptions(inp, sopt);
2259                                 break;
2260
2261 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2262                         case IPV6_IPSEC_POLICY:
2263                                 if (IPSEC_ENABLED(ipv6)) {
2264                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2265                                         break;
2266                                 }
2267                                 /* FALLTHROUGH */
2268 #endif /* IPSEC */
2269                         default:
2270                                 error = ENOPROTOOPT;
2271                                 break;
2272                         }
2273                         break;
2274                 }
2275         }
2276         return (error);
2277 }
2278
2279 int
2280 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2281 {
2282         int error = 0, optval, optlen;
2283         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2284         struct inpcb *inp = sotoinpcb(so);
2285         int level, op, optname;
2286
2287         level = sopt->sopt_level;
2288         op = sopt->sopt_dir;
2289         optname = sopt->sopt_name;
2290         optlen = sopt->sopt_valsize;
2291
2292         if (level != IPPROTO_IPV6) {
2293                 return (EINVAL);
2294         }
2295
2296         switch (optname) {
2297         case IPV6_CHECKSUM:
2298                 /*
2299                  * For ICMPv6 sockets, no modification allowed for checksum
2300                  * offset, permit "no change" values to help existing apps.
2301                  *
2302                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2303                  * for an ICMPv6 socket will fail."
2304                  * The current behavior does not meet RFC3542.
2305                  */
2306                 switch (op) {
2307                 case SOPT_SET:
2308                         if (optlen != sizeof(int)) {
2309                                 error = EINVAL;
2310                                 break;
2311                         }
2312                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2313                                             sizeof(optval));
2314                         if (error)
2315                                 break;
2316                         if (optval < -1 || (optval % 2) != 0) {
2317                                 /*
2318                                  * The API assumes non-negative even offset
2319                                  * values or -1 as a special value.
2320                                  */
2321                                 error = EINVAL;
2322                         } else if (so->so_proto->pr_protocol ==
2323                             IPPROTO_ICMPV6) {
2324                                 if (optval != icmp6off)
2325                                         error = EINVAL;
2326                         } else
2327                                 inp->in6p_cksum = optval;
2328                         break;
2329
2330                 case SOPT_GET:
2331                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2332                                 optval = icmp6off;
2333                         else
2334                                 optval = inp->in6p_cksum;
2335
2336                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2337                         break;
2338
2339                 default:
2340                         error = EINVAL;
2341                         break;
2342                 }
2343                 break;
2344
2345         default:
2346                 error = ENOPROTOOPT;
2347                 break;
2348         }
2349
2350         return (error);
2351 }
2352
2353 /*
2354  * Set up IP6 options in pcb for insertion in output packets or
2355  * specifying behavior of outgoing packets.
2356  */
2357 static int
2358 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2359     struct socket *so, struct sockopt *sopt)
2360 {
2361         struct ip6_pktopts *opt = *pktopt;
2362         int error = 0;
2363         struct thread *td = sopt->sopt_td;
2364
2365         /* turn off any old options. */
2366         if (opt) {
2367 #ifdef DIAGNOSTIC
2368                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2369                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2370                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2371                         printf("ip6_pcbopts: all specified options are cleared.\n");
2372 #endif
2373                 ip6_clearpktopts(opt, -1);
2374         } else
2375                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2376         *pktopt = NULL;
2377
2378         if (!m || m->m_len == 0) {
2379                 /*
2380                  * Only turning off any previous options, regardless of
2381                  * whether the opt is just created or given.
2382                  */
2383                 free(opt, M_IP6OPT);
2384                 return (0);
2385         }
2386
2387         /*  set options specified by user. */
2388         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2389             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2390                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2391                 free(opt, M_IP6OPT);
2392                 return (error);
2393         }
2394         *pktopt = opt;
2395         return (0);
2396 }
2397
2398 /*
2399  * initialize ip6_pktopts.  beware that there are non-zero default values in
2400  * the struct.
2401  */
2402 void
2403 ip6_initpktopts(struct ip6_pktopts *opt)
2404 {
2405
2406         bzero(opt, sizeof(*opt));
2407         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2408         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2409         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2410         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2411 }
2412
2413 static int
2414 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2415     struct ucred *cred, int uproto)
2416 {
2417         struct ip6_pktopts *opt;
2418
2419         if (*pktopt == NULL) {
2420                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2421                     M_NOWAIT);
2422                 if (*pktopt == NULL)
2423                         return (ENOBUFS);
2424                 ip6_initpktopts(*pktopt);
2425         }
2426         opt = *pktopt;
2427
2428         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2429 }
2430
2431 #define GET_PKTOPT_VAR(field, lenexpr) do {                                     \
2432         if (pktopt && pktopt->field) {                                          \
2433                 INP_RUNLOCK(inp);                                               \
2434                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK);         \
2435                 malloc_optdata = true;                                          \
2436                 INP_RLOCK(inp);                                                 \
2437                 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {            \
2438                         INP_RUNLOCK(inp);                                       \
2439                         free(optdata, M_TEMP);                                  \
2440                         return (ECONNRESET);                                    \
2441                 }                                                               \
2442                 pktopt = inp->in6p_outputopts;                                  \
2443                 if (pktopt && pktopt->field) {                                  \
2444                         optdatalen = min(lenexpr, sopt->sopt_valsize);          \
2445                         bcopy(&pktopt->field, optdata, optdatalen);             \
2446                 } else {                                                        \
2447                         free(optdata, M_TEMP);                                  \
2448                         optdata = NULL;                                         \
2449                         malloc_optdata = false;                                 \
2450                 }                                                               \
2451         }                                                                       \
2452 } while(0)
2453
2454 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                         \
2455         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2456
2457 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                        \
2458         pktopt->field->sa_len)
2459
2460 static int
2461 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2462 {
2463         void *optdata = NULL;
2464         bool malloc_optdata = false;
2465         int optdatalen = 0;
2466         int error = 0;
2467         struct in6_pktinfo null_pktinfo;
2468         int deftclass = 0, on;
2469         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2470         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2471         struct ip6_pktopts *pktopt;
2472
2473         INP_RLOCK(inp);
2474         pktopt = inp->in6p_outputopts;
2475
2476         switch (optname) {
2477         case IPV6_PKTINFO:
2478                 optdata = (void *)&null_pktinfo;
2479                 if (pktopt && pktopt->ip6po_pktinfo) {
2480                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2481                             sizeof(null_pktinfo));
2482                         in6_clearscope(&null_pktinfo.ipi6_addr);
2483                 } else {
2484                         /* XXX: we don't have to do this every time... */
2485                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2486                 }
2487                 optdatalen = sizeof(struct in6_pktinfo);
2488                 break;
2489         case IPV6_TCLASS:
2490                 if (pktopt && pktopt->ip6po_tclass >= 0)
2491                         deftclass = pktopt->ip6po_tclass;
2492                 optdata = (void *)&deftclass;
2493                 optdatalen = sizeof(int);
2494                 break;
2495         case IPV6_HOPOPTS:
2496                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2497                 break;
2498         case IPV6_RTHDR:
2499                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2500                 break;
2501         case IPV6_RTHDRDSTOPTS:
2502                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2503                 break;
2504         case IPV6_DSTOPTS:
2505                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2506                 break;
2507         case IPV6_NEXTHOP:
2508                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2509                 break;
2510         case IPV6_USE_MIN_MTU:
2511                 if (pktopt)
2512                         defminmtu = pktopt->ip6po_minmtu;
2513                 optdata = (void *)&defminmtu;
2514                 optdatalen = sizeof(int);
2515                 break;
2516         case IPV6_DONTFRAG:
2517                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2518                         on = 1;
2519                 else
2520                         on = 0;
2521                 optdata = (void *)&on;
2522                 optdatalen = sizeof(on);
2523                 break;
2524         case IPV6_PREFER_TEMPADDR:
2525                 if (pktopt)
2526                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2527                 optdata = (void *)&defpreftemp;
2528                 optdatalen = sizeof(int);
2529                 break;
2530         default:                /* should not happen */
2531 #ifdef DIAGNOSTIC
2532                 panic("ip6_getpcbopt: unexpected option\n");
2533 #endif
2534                 INP_RUNLOCK(inp);
2535                 return (ENOPROTOOPT);
2536         }
2537         INP_RUNLOCK(inp);
2538
2539         error = sooptcopyout(sopt, optdata, optdatalen);
2540         if (malloc_optdata)
2541                 free(optdata, M_TEMP);
2542
2543         return (error);
2544 }
2545
2546 void
2547 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2548 {
2549         if (pktopt == NULL)
2550                 return;
2551
2552         if (optname == -1 || optname == IPV6_PKTINFO) {
2553                 if (pktopt->ip6po_pktinfo)
2554                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2555                 pktopt->ip6po_pktinfo = NULL;
2556         }
2557         if (optname == -1 || optname == IPV6_HOPLIMIT)
2558                 pktopt->ip6po_hlim = -1;
2559         if (optname == -1 || optname == IPV6_TCLASS)
2560                 pktopt->ip6po_tclass = -1;
2561         if (optname == -1 || optname == IPV6_NEXTHOP) {
2562                 if (pktopt->ip6po_nextroute.ro_rt) {
2563                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2564                         pktopt->ip6po_nextroute.ro_rt = NULL;
2565                 }
2566                 if (pktopt->ip6po_nexthop)
2567                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2568                 pktopt->ip6po_nexthop = NULL;
2569         }
2570         if (optname == -1 || optname == IPV6_HOPOPTS) {
2571                 if (pktopt->ip6po_hbh)
2572                         free(pktopt->ip6po_hbh, M_IP6OPT);
2573                 pktopt->ip6po_hbh = NULL;
2574         }
2575         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2576                 if (pktopt->ip6po_dest1)
2577                         free(pktopt->ip6po_dest1, M_IP6OPT);
2578                 pktopt->ip6po_dest1 = NULL;
2579         }
2580         if (optname == -1 || optname == IPV6_RTHDR) {
2581                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2582                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2583                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2584                 if (pktopt->ip6po_route.ro_rt) {
2585                         RTFREE(pktopt->ip6po_route.ro_rt);
2586                         pktopt->ip6po_route.ro_rt = NULL;
2587                 }
2588         }
2589         if (optname == -1 || optname == IPV6_DSTOPTS) {
2590                 if (pktopt->ip6po_dest2)
2591                         free(pktopt->ip6po_dest2, M_IP6OPT);
2592                 pktopt->ip6po_dest2 = NULL;
2593         }
2594 }
2595
2596 #define PKTOPT_EXTHDRCPY(type) \
2597 do {\
2598         if (src->type) {\
2599                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2600                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2601                 if (dst->type == NULL)\
2602                         goto bad;\
2603                 bcopy(src->type, dst->type, hlen);\
2604         }\
2605 } while (/*CONSTCOND*/ 0)
2606
2607 static int
2608 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2609 {
2610         if (dst == NULL || src == NULL)  {
2611                 printf("ip6_clearpktopts: invalid argument\n");
2612                 return (EINVAL);
2613         }
2614
2615         dst->ip6po_hlim = src->ip6po_hlim;
2616         dst->ip6po_tclass = src->ip6po_tclass;
2617         dst->ip6po_flags = src->ip6po_flags;
2618         dst->ip6po_minmtu = src->ip6po_minmtu;
2619         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2620         if (src->ip6po_pktinfo) {
2621                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2622                     M_IP6OPT, canwait);
2623                 if (dst->ip6po_pktinfo == NULL)
2624                         goto bad;
2625                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2626         }
2627         if (src->ip6po_nexthop) {
2628                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2629                     M_IP6OPT, canwait);
2630                 if (dst->ip6po_nexthop == NULL)
2631                         goto bad;
2632                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2633                     src->ip6po_nexthop->sa_len);
2634         }
2635         PKTOPT_EXTHDRCPY(ip6po_hbh);
2636         PKTOPT_EXTHDRCPY(ip6po_dest1);
2637         PKTOPT_EXTHDRCPY(ip6po_dest2);
2638         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2639         return (0);
2640
2641   bad:
2642         ip6_clearpktopts(dst, -1);
2643         return (ENOBUFS);
2644 }
2645 #undef PKTOPT_EXTHDRCPY
2646
2647 struct ip6_pktopts *
2648 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2649 {
2650         int error;
2651         struct ip6_pktopts *dst;
2652
2653         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2654         if (dst == NULL)
2655                 return (NULL);
2656         ip6_initpktopts(dst);
2657
2658         if ((error = copypktopts(dst, src, canwait)) != 0) {
2659                 free(dst, M_IP6OPT);
2660                 return (NULL);
2661         }
2662
2663         return (dst);
2664 }
2665
2666 void
2667 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2668 {
2669         if (pktopt == NULL)
2670                 return;
2671
2672         ip6_clearpktopts(pktopt, -1);
2673
2674         free(pktopt, M_IP6OPT);
2675 }
2676
2677 /*
2678  * Set IPv6 outgoing packet options based on advanced API.
2679  */
2680 int
2681 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2682     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2683 {
2684         struct cmsghdr *cm = NULL;
2685
2686         if (control == NULL || opt == NULL)
2687                 return (EINVAL);
2688
2689         ip6_initpktopts(opt);
2690         if (stickyopt) {
2691                 int error;
2692
2693                 /*
2694                  * If stickyopt is provided, make a local copy of the options
2695                  * for this particular packet, then override them by ancillary
2696                  * objects.
2697                  * XXX: copypktopts() does not copy the cached route to a next
2698                  * hop (if any).  This is not very good in terms of efficiency,
2699                  * but we can allow this since this option should be rarely
2700                  * used.
2701                  */
2702                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2703                         return (error);
2704         }
2705
2706         /*
2707          * XXX: Currently, we assume all the optional information is stored
2708          * in a single mbuf.
2709          */
2710         if (control->m_next)
2711                 return (EINVAL);
2712
2713         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2714             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2715                 int error;
2716
2717                 if (control->m_len < CMSG_LEN(0))
2718                         return (EINVAL);
2719
2720                 cm = mtod(control, struct cmsghdr *);
2721                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2722                         return (EINVAL);
2723                 if (cm->cmsg_level != IPPROTO_IPV6)
2724                         continue;
2725
2726                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2727                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2728                 if (error)
2729                         return (error);
2730         }
2731
2732         return (0);
2733 }
2734
2735 /*
2736  * Set a particular packet option, as a sticky option or an ancillary data
2737  * item.  "len" can be 0 only when it's a sticky option.
2738  * We have 4 cases of combination of "sticky" and "cmsg":
2739  * "sticky=0, cmsg=0": impossible
2740  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2741  * "sticky=1, cmsg=0": RFC3542 socket option
2742  * "sticky=1, cmsg=1": RFC2292 socket option
2743  */
2744 static int
2745 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2746     struct ucred *cred, int sticky, int cmsg, int uproto)
2747 {
2748         int minmtupolicy, preftemp;
2749         int error;
2750
2751         if (!sticky && !cmsg) {
2752 #ifdef DIAGNOSTIC
2753                 printf("ip6_setpktopt: impossible case\n");
2754 #endif
2755                 return (EINVAL);
2756         }
2757
2758         /*
2759          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2760          * not be specified in the context of RFC3542.  Conversely,
2761          * RFC3542 types should not be specified in the context of RFC2292.
2762          */
2763         if (!cmsg) {
2764                 switch (optname) {
2765                 case IPV6_2292PKTINFO:
2766                 case IPV6_2292HOPLIMIT:
2767                 case IPV6_2292NEXTHOP:
2768                 case IPV6_2292HOPOPTS:
2769                 case IPV6_2292DSTOPTS:
2770                 case IPV6_2292RTHDR:
2771                 case IPV6_2292PKTOPTIONS:
2772                         return (ENOPROTOOPT);
2773                 }
2774         }
2775         if (sticky && cmsg) {
2776                 switch (optname) {
2777                 case IPV6_PKTINFO:
2778                 case IPV6_HOPLIMIT:
2779                 case IPV6_NEXTHOP:
2780                 case IPV6_HOPOPTS:
2781                 case IPV6_DSTOPTS:
2782                 case IPV6_RTHDRDSTOPTS:
2783                 case IPV6_RTHDR:
2784                 case IPV6_USE_MIN_MTU:
2785                 case IPV6_DONTFRAG:
2786                 case IPV6_TCLASS:
2787                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2788                         return (ENOPROTOOPT);
2789                 }
2790         }
2791
2792         switch (optname) {
2793         case IPV6_2292PKTINFO:
2794         case IPV6_PKTINFO:
2795         {
2796                 struct ifnet *ifp = NULL;
2797                 struct in6_pktinfo *pktinfo;
2798
2799                 if (len != sizeof(struct in6_pktinfo))
2800                         return (EINVAL);
2801
2802                 pktinfo = (struct in6_pktinfo *)buf;
2803
2804                 /*
2805                  * An application can clear any sticky IPV6_PKTINFO option by
2806                  * doing a "regular" setsockopt with ipi6_addr being
2807                  * in6addr_any and ipi6_ifindex being zero.
2808                  * [RFC 3542, Section 6]
2809                  */
2810                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2811                     pktinfo->ipi6_ifindex == 0 &&
2812                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2813                         ip6_clearpktopts(opt, optname);
2814                         break;
2815                 }
2816
2817                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2818                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2819                         return (EINVAL);
2820                 }
2821                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2822                         return (EINVAL);
2823                 /* validate the interface index if specified. */
2824                 if (pktinfo->ipi6_ifindex > V_if_index)
2825                          return (ENXIO);
2826                 if (pktinfo->ipi6_ifindex) {
2827                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2828                         if (ifp == NULL)
2829                                 return (ENXIO);
2830                 }
2831                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2832                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2833                         return (ENETDOWN);
2834
2835                 if (ifp != NULL &&
2836                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2837                         struct in6_ifaddr *ia;
2838
2839                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2840                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2841                         if (ia == NULL)
2842                                 return (EADDRNOTAVAIL);
2843                         ifa_free(&ia->ia_ifa);
2844                 }
2845                 /*
2846                  * We store the address anyway, and let in6_selectsrc()
2847                  * validate the specified address.  This is because ipi6_addr
2848                  * may not have enough information about its scope zone, and
2849                  * we may need additional information (such as outgoing
2850                  * interface or the scope zone of a destination address) to
2851                  * disambiguate the scope.
2852                  * XXX: the delay of the validation may confuse the
2853                  * application when it is used as a sticky option.
2854                  */
2855                 if (opt->ip6po_pktinfo == NULL) {
2856                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2857                             M_IP6OPT, M_NOWAIT);
2858                         if (opt->ip6po_pktinfo == NULL)
2859                                 return (ENOBUFS);
2860                 }
2861                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2862                 break;
2863         }
2864
2865         case IPV6_2292HOPLIMIT:
2866         case IPV6_HOPLIMIT:
2867         {
2868                 int *hlimp;
2869
2870                 /*
2871                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2872                  * to simplify the ordering among hoplimit options.
2873                  */
2874                 if (optname == IPV6_HOPLIMIT && sticky)
2875                         return (ENOPROTOOPT);
2876
2877                 if (len != sizeof(int))
2878                         return (EINVAL);
2879                 hlimp = (int *)buf;
2880                 if (*hlimp < -1 || *hlimp > 255)
2881                         return (EINVAL);
2882
2883                 opt->ip6po_hlim = *hlimp;
2884                 break;
2885         }
2886
2887         case IPV6_TCLASS:
2888         {
2889                 int tclass;
2890
2891                 if (len != sizeof(int))
2892                         return (EINVAL);
2893                 tclass = *(int *)buf;
2894                 if (tclass < -1 || tclass > 255)
2895                         return (EINVAL);
2896
2897                 opt->ip6po_tclass = tclass;
2898                 break;
2899         }
2900
2901         case IPV6_2292NEXTHOP:
2902         case IPV6_NEXTHOP:
2903                 if (cred != NULL) {
2904                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2905                         if (error)
2906                                 return (error);
2907                 }
2908
2909                 if (len == 0) { /* just remove the option */
2910                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
2911                         break;
2912                 }
2913
2914                 /* check if cmsg_len is large enough for sa_len */
2915                 if (len < sizeof(struct sockaddr) || len < *buf)
2916                         return (EINVAL);
2917
2918                 switch (((struct sockaddr *)buf)->sa_family) {
2919                 case AF_INET6:
2920                 {
2921                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2922                         int error;
2923
2924                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2925                                 return (EINVAL);
2926
2927                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2928                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2929                                 return (EINVAL);
2930                         }
2931                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2932                             != 0) {
2933                                 return (error);
2934                         }
2935                         break;
2936                 }
2937                 case AF_LINK:   /* should eventually be supported */
2938                 default:
2939                         return (EAFNOSUPPORT);
2940                 }
2941
2942                 /* turn off the previous option, then set the new option. */
2943                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2944                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2945                 if (opt->ip6po_nexthop == NULL)
2946                         return (ENOBUFS);
2947                 bcopy(buf, opt->ip6po_nexthop, *buf);
2948                 break;
2949
2950         case IPV6_2292HOPOPTS:
2951         case IPV6_HOPOPTS:
2952         {
2953                 struct ip6_hbh *hbh;
2954                 int hbhlen;
2955
2956                 /*
2957                  * XXX: We don't allow a non-privileged user to set ANY HbH
2958                  * options, since per-option restriction has too much
2959                  * overhead.
2960                  */
2961                 if (cred != NULL) {
2962                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2963                         if (error)
2964                                 return (error);
2965                 }
2966
2967                 if (len == 0) {
2968                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
2969                         break;  /* just remove the option */
2970                 }
2971
2972                 /* message length validation */
2973                 if (len < sizeof(struct ip6_hbh))
2974                         return (EINVAL);
2975                 hbh = (struct ip6_hbh *)buf;
2976                 hbhlen = (hbh->ip6h_len + 1) << 3;
2977                 if (len != hbhlen)
2978                         return (EINVAL);
2979
2980                 /* turn off the previous option, then set the new option. */
2981                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2982                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2983                 if (opt->ip6po_hbh == NULL)
2984                         return (ENOBUFS);
2985                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2986
2987                 break;
2988         }
2989
2990         case IPV6_2292DSTOPTS:
2991         case IPV6_DSTOPTS:
2992         case IPV6_RTHDRDSTOPTS:
2993         {
2994                 struct ip6_dest *dest, **newdest = NULL;
2995                 int destlen;
2996
2997                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
2998                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2999                         if (error)
3000                                 return (error);
3001                 }
3002
3003                 if (len == 0) {
3004                         ip6_clearpktopts(opt, optname);
3005                         break;  /* just remove the option */
3006                 }
3007
3008                 /* message length validation */
3009                 if (len < sizeof(struct ip6_dest))
3010                         return (EINVAL);
3011                 dest = (struct ip6_dest *)buf;
3012                 destlen = (dest->ip6d_len + 1) << 3;
3013                 if (len != destlen)
3014                         return (EINVAL);
3015
3016                 /*
3017                  * Determine the position that the destination options header
3018                  * should be inserted; before or after the routing header.
3019                  */
3020                 switch (optname) {
3021                 case IPV6_2292DSTOPTS:
3022                         /*
3023                          * The old advacned API is ambiguous on this point.
3024                          * Our approach is to determine the position based
3025                          * according to the existence of a routing header.
3026                          * Note, however, that this depends on the order of the
3027                          * extension headers in the ancillary data; the 1st
3028                          * part of the destination options header must appear
3029                          * before the routing header in the ancillary data,
3030                          * too.
3031                          * RFC3542 solved the ambiguity by introducing
3032                          * separate ancillary data or option types.
3033                          */
3034                         if (opt->ip6po_rthdr == NULL)
3035                                 newdest = &opt->ip6po_dest1;
3036                         else
3037                                 newdest = &opt->ip6po_dest2;
3038                         break;
3039                 case IPV6_RTHDRDSTOPTS:
3040                         newdest = &opt->ip6po_dest1;
3041                         break;
3042                 case IPV6_DSTOPTS:
3043                         newdest = &opt->ip6po_dest2;
3044                         break;
3045                 }
3046
3047                 /* turn off the previous option, then set the new option. */
3048                 ip6_clearpktopts(opt, optname);
3049                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3050                 if (*newdest == NULL)
3051                         return (ENOBUFS);
3052                 bcopy(dest, *newdest, destlen);
3053
3054                 break;
3055         }
3056
3057         case IPV6_2292RTHDR:
3058         case IPV6_RTHDR:
3059         {
3060                 struct ip6_rthdr *rth;
3061                 int rthlen;
3062
3063                 if (len == 0) {
3064                         ip6_clearpktopts(opt, IPV6_RTHDR);
3065                         break;  /* just remove the option */
3066                 }
3067
3068                 /* message length validation */
3069                 if (len < sizeof(struct ip6_rthdr))
3070                         return (EINVAL);
3071                 rth = (struct ip6_rthdr *)buf;
3072                 rthlen = (rth->ip6r_len + 1) << 3;
3073                 if (len != rthlen)
3074                         return (EINVAL);
3075
3076                 switch (rth->ip6r_type) {
3077                 case IPV6_RTHDR_TYPE_0:
3078                         if (rth->ip6r_len == 0) /* must contain one addr */
3079                                 return (EINVAL);
3080                         if (rth->ip6r_len % 2) /* length must be even */
3081                                 return (EINVAL);
3082                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3083                                 return (EINVAL);
3084                         break;
3085                 default:
3086                         return (EINVAL);        /* not supported */
3087                 }
3088
3089                 /* turn off the previous option */
3090                 ip6_clearpktopts(opt, IPV6_RTHDR);
3091                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3092                 if (opt->ip6po_rthdr == NULL)
3093                         return (ENOBUFS);
3094                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3095
3096                 break;
3097         }
3098
3099         case IPV6_USE_MIN_MTU:
3100                 if (len != sizeof(int))
3101                         return (EINVAL);
3102                 minmtupolicy = *(int *)buf;
3103                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3104                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3105                     minmtupolicy != IP6PO_MINMTU_ALL) {
3106                         return (EINVAL);
3107                 }
3108                 opt->ip6po_minmtu = minmtupolicy;
3109                 break;
3110
3111         case IPV6_DONTFRAG:
3112                 if (len != sizeof(int))
3113                         return (EINVAL);
3114
3115                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3116                         /*
3117                          * we ignore this option for TCP sockets.
3118                          * (RFC3542 leaves this case unspecified.)
3119                          */
3120                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3121                 } else
3122                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3123                 break;
3124
3125         case IPV6_PREFER_TEMPADDR:
3126                 if (len != sizeof(int))
3127                         return (EINVAL);
3128                 preftemp = *(int *)buf;
3129                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3130                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3131                     preftemp != IP6PO_TEMPADDR_PREFER) {
3132                         return (EINVAL);
3133                 }
3134                 opt->ip6po_prefer_tempaddr = preftemp;
3135                 break;
3136
3137         default:
3138                 return (ENOPROTOOPT);
3139         } /* end of switch */
3140
3141         return (0);
3142 }
3143
3144 /*
3145  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3146  * packet to the input queue of a specified interface.  Note that this
3147  * calls the output routine of the loopback "driver", but with an interface
3148  * pointer that might NOT be &loif -- easier than replicating that code here.
3149  */
3150 void
3151 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3152 {
3153         struct mbuf *copym;
3154         struct ip6_hdr *ip6;
3155
3156         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3157         if (copym == NULL)
3158                 return;
3159
3160         /*
3161          * Make sure to deep-copy IPv6 header portion in case the data
3162          * is in an mbuf cluster, so that we can safely override the IPv6
3163          * header portion later.
3164          */
3165         if (!M_WRITABLE(copym) ||
3166             copym->m_len < sizeof(struct ip6_hdr)) {
3167                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3168                 if (copym == NULL)
3169                         return;
3170         }
3171         ip6 = mtod(copym, struct ip6_hdr *);
3172         /*
3173          * clear embedded scope identifiers if necessary.
3174          * in6_clearscope will touch the addresses only when necessary.
3175          */
3176         in6_clearscope(&ip6->ip6_src);
3177         in6_clearscope(&ip6->ip6_dst);
3178         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3179                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3180                     CSUM_PSEUDO_HDR;
3181                 copym->m_pkthdr.csum_data = 0xffff;
3182         }
3183         if_simloop(ifp, copym, AF_INET6, 0);
3184 }
3185
3186 /*
3187  * Chop IPv6 header off from the payload.
3188  */
3189 static int
3190 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3191 {
3192         struct mbuf *mh;
3193         struct ip6_hdr *ip6;
3194
3195         ip6 = mtod(m, struct ip6_hdr *);
3196         if (m->m_len > sizeof(*ip6)) {
3197                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3198                 if (mh == NULL) {
3199                         m_freem(m);
3200                         return ENOBUFS;
3201                 }
3202                 m_move_pkthdr(mh, m);
3203                 M_ALIGN(mh, sizeof(*ip6));
3204                 m->m_len -= sizeof(*ip6);
3205                 m->m_data += sizeof(*ip6);
3206                 mh->m_next = m;
3207                 m = mh;
3208                 m->m_len = sizeof(*ip6);
3209                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3210         }
3211         exthdrs->ip6e_ip6 = m;
3212         return 0;
3213 }
3214
3215 /*
3216  * Compute IPv6 extension header length.
3217  */
3218 int
3219 ip6_optlen(struct inpcb *inp)
3220 {
3221         int len;
3222
3223         if (!inp->in6p_outputopts)
3224                 return 0;
3225
3226         len = 0;
3227 #define elen(x) \
3228     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3229
3230         len += elen(inp->in6p_outputopts->ip6po_hbh);
3231         if (inp->in6p_outputopts->ip6po_rthdr)
3232                 /* dest1 is valid with rthdr only */
3233                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3234         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3235         len += elen(inp->in6p_outputopts->ip6po_dest2);
3236         return len;
3237 #undef elen
3238 }