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_ratelimit.h"
  71 #include "opt_ipsec.h"
  72 #include "opt_sctp.h"
  73 #include "opt_route.h"
  74 #include "opt_rss.h"
  75
  76 #include <sys/param.h>
  77 #include <sys/kernel.h>
  78 #include <sys/malloc.h>
  79 #include <sys/mbuf.h>
  80 #include <sys/errno.h>
  81 #include <sys/priv.h>
  82 #include <sys/proc.h>
  83 #include <sys/protosw.h>
  84 #include <sys/socket.h>
  85 #include <sys/socketvar.h>
  86 #include <sys/syslog.h>
  87 #include <sys/ucred.h>
  88
  89 #include <machine/in_cksum.h>
  90
  91 #include <net/if.h>
  92 #include <net/if_var.h>
  93 #include <net/if_llatbl.h>
  94 #include <net/netisr.h>
  95 #include <net/route.h>
  96 #include <net/pfil.h>
  97 #include <net/rss_config.h>
  98 #include <net/vnet.h>
  99
 100 #include <netinet/in.h>
 101 #include <netinet/in_var.h>
 102 #include <netinet/ip_var.h>
 103 #include <netinet6/in6_fib.h>
 104 #include <netinet6/in6_var.h>
 105 #include <netinet/ip6.h>
 106 #include <netinet/icmp6.h>
 107 #include <netinet6/ip6_var.h>
 108 #include <netinet/in_pcb.h>
 109 #include <netinet/tcp_var.h>
 110 #include <netinet6/nd6.h>
 111 #include <netinet6/in6_rss.h>
 112
 113 #include <netipsec/ipsec_support.h>
 114 #ifdef SCTP
 115 #include <netinet/sctp.h>
 116 #include <netinet/sctp_crc32.h>
 117 #endif
 118
 119 #include <netinet6/ip6protosw.h>
 120 #include <netinet6/scope6_var.h>
 121
 122 extern int in6_mcast_loop;
 123
 124 struct ip6_exthdrs {
 125         struct mbuf *ip6e_ip6;
 126         struct mbuf *ip6e_hbh;
 127         struct mbuf *ip6e_dest1;
 128         struct mbuf *ip6e_rthdr;
 129         struct mbuf *ip6e_dest2;
 130 };
 131
 132 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 133
 134 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 135                            struct ucred *, int);
 136 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 137         struct socket *, struct sockopt *);
 138 static int ip6_getpcbopt(struct inpcb *, int, struct sockopt *);
 139 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 140         struct ucred *, int, int, int);
 141
 142 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 143 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 144         struct ip6_frag **);
 145 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 146 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 147 static int ip6_getpmtu(struct route_in6 *, int,
 148         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int,
 149         u_int);
 150 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 151         u_long *, int *, u_int);
 152 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 153 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 154
 155
 156 /*
 157  * Make an extension header from option data.  hp is the source, and
 158  * mp is the destination.
 159  */
 160 #define MAKE_EXTHDR(hp, mp)                                             \
 161     do {                                                                \
 162         if (hp) {                                                       \
 163                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 164                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 165                     ((eh)->ip6e_len + 1) << 3);                         \
 166                 if (error)                                              \
 167                         goto freehdrs;                                  \
 168         }                                                               \
 169     } while (/*CONSTCOND*/ 0)
 170
 171 /*
 172  * Form a chain of extension headers.
 173  * m is the extension header mbuf
 174  * mp is the previous mbuf in the chain
 175  * p is the next header
 176  * i is the type of option.
 177  */
 178 #define MAKE_CHAIN(m, mp, p, i)\
 179     do {\
 180         if (m) {\
 181                 if (!hdrsplit) \
 182                         panic("assumption failed: hdr not split"); \
 183                 *mtod((m), u_char *) = *(p);\
 184                 *(p) = (i);\
 185                 p = mtod((m), u_char *);\
 186                 (m)->m_next = (mp)->m_next;\
 187                 (mp)->m_next = (m);\
 188                 (mp) = (m);\
 189         }\
 190     } while (/*CONSTCOND*/ 0)
 191
 192 void
 193 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 194 {
 195         u_short csum;
 196
 197         csum = in_cksum_skip(m, offset + plen, offset);
 198         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 199                 csum = 0xffff;
 200         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 201
 202         if (offset + sizeof(csum) > m->m_len)
 203                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
 204         else
 205                 *(u_short *)mtodo(m, offset) = csum;
 206 }
 207
 208 int
 209 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 210     int fraglen , uint32_t id)
 211 {
 212         struct mbuf *m, **mnext, *m_frgpart;
 213         struct ip6_hdr *ip6, *mhip6;
 214         struct ip6_frag *ip6f;
 215         int off;
 216         int error;
 217         int tlen = m0->m_pkthdr.len;
 218
 219         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 220
 221         m = m0;
 222         ip6 = mtod(m, struct ip6_hdr *);
 223         mnext = &m->m_nextpkt;
 224
 225         for (off = hlen; off < tlen; off += fraglen) {
 226                 m = m_gethdr(M_NOWAIT, MT_DATA);
 227                 if (!m) {
 228                         IP6STAT_INC(ip6s_odropped);
 229                         return (ENOBUFS);
 230                 }
 231
 232                 /*
 233                  * Make sure the complete packet header gets copied
 234                  * from the originating mbuf to the newly created
 235                  * mbuf. This also ensures that existing firewall
 236                  * classification(s), VLAN tags and so on get copied
 237                  * to the resulting fragmented packet(s):
 238                  */
 239                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 240                         m_free(m);
 241                         IP6STAT_INC(ip6s_odropped);
 242                         return (ENOBUFS);
 243                 }
 244
 245                 *mnext = m;
 246                 mnext = &m->m_nextpkt;
 247                 m->m_data += max_linkhdr;
 248                 mhip6 = mtod(m, struct ip6_hdr *);
 249                 *mhip6 = *ip6;
 250                 m->m_len = sizeof(*mhip6);
 251                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 252                 if (error) {
 253                         IP6STAT_INC(ip6s_odropped);
 254                         return (error);
 255                 }
 256                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 257                 if (off + fraglen >= tlen)
 258                         fraglen = tlen - off;
 259                 else
 260                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 261                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 262                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 263                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 264                         IP6STAT_INC(ip6s_odropped);
 265                         return (ENOBUFS);
 266                 }
 267                 m_cat(m, m_frgpart);
 268                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 269                 ip6f->ip6f_reserved = 0;
 270                 ip6f->ip6f_ident = id;
 271                 ip6f->ip6f_nxt = nextproto;
 272                 IP6STAT_INC(ip6s_ofragments);
 273                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 274         }
 275
 276         return (0);
 277 }
 278
 279 /*
 280  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 281  * header (with pri, len, nxt, hlim, src, dst).
 282  * This function may modify ver and hlim only.
 283  * The mbuf chain containing the packet will be freed.
 284  * The mbuf opt, if present, will not be freed.
 285  * If route_in6 ro is present and has ro_rt initialized, route lookup would be
 286  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 287  * then result of route lookup is stored in ro->ro_rt.
 288  *
 289  * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
 290  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 291  * which is rt_mtu.
 292  *
 293  * ifpp - XXX: just for statistics
 294  */
 295 /*
 296  * XXX TODO: no flowid is assigned for outbound flows?
 297  */
 298 int
 299 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 300     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 301     struct ifnet **ifpp, struct inpcb *inp)
 302 {
 303         struct ip6_hdr *ip6;
 304         struct ifnet *ifp, *origifp;
 305         struct mbuf *m = m0;
 306         struct mbuf *mprev = NULL;
 307         int hlen, tlen, len;
 308         struct route_in6 ip6route;
 309         struct rtentry *rt = NULL;
 310         struct sockaddr_in6 *dst, src_sa, dst_sa;
 311         struct in6_addr odst;
 312         int error = 0;
 313         struct in6_ifaddr *ia = NULL;
 314         u_long mtu;
 315         int alwaysfrag, dontfrag;
 316         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 317         struct ip6_exthdrs exthdrs;
 318         struct in6_addr src0, dst0;
 319         u_int32_t zone;
 320         struct route_in6 *ro_pmtu = NULL;
 321         int hdrsplit = 0;
 322         int sw_csum, tso;
 323         int needfiblookup;
 324         uint32_t fibnum;
 325         struct m_tag *fwd_tag = NULL;
 326         uint32_t id;
 327
 328         if (inp != NULL) {
 329                 INP_LOCK_ASSERT(inp);
 330                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 331                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 332                         /* unconditionally set flowid */
 333                         m->m_pkthdr.flowid = inp->inp_flowid;
 334                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 335                 }
 336 #ifdef NUMA
 337                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 338 #endif
 339         }
 340
 341 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 342         /*
 343          * IPSec checking which handles several cases.
 344          * FAST IPSEC: We re-injected the packet.
 345          * XXX: need scope argument.
 346          */
 347         if (IPSEC_ENABLED(ipv6)) {
 348                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 349                         if (error == EINPROGRESS)
 350                                 error = 0;
 351                         goto done;
 352                 }
 353         }
 354 #endif /* IPSEC */
 355
 356         bzero(&exthdrs, sizeof(exthdrs));
 357         if (opt) {
 358                 /* Hop-by-Hop options header */
 359                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 360                 /* Destination options header(1st part) */
 361                 if (opt->ip6po_rthdr) {
 362                         /*
 363                          * Destination options header(1st part)
 364                          * This only makes sense with a routing header.
 365                          * See Section 9.2 of RFC 3542.
 366                          * Disabling this part just for MIP6 convenience is
 367                          * a bad idea.  We need to think carefully about a
 368                          * way to make the advanced API coexist with MIP6
 369                          * options, which might automatically be inserted in
 370                          * the kernel.
 371                          */
 372                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 373                 }
 374                 /* Routing header */
 375                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 376                 /* Destination options header(2nd part) */
 377                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 378         }
 379
 380         /*
 381          * Calculate the total length of the extension header chain.
 382          * Keep the length of the unfragmentable part for fragmentation.
 383          */
 384         optlen = 0;
 385         if (exthdrs.ip6e_hbh)
 386                 optlen += exthdrs.ip6e_hbh->m_len;
 387         if (exthdrs.ip6e_dest1)
 388                 optlen += exthdrs.ip6e_dest1->m_len;
 389         if (exthdrs.ip6e_rthdr)
 390                 optlen += exthdrs.ip6e_rthdr->m_len;
 391         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 392
 393         /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
 394         if (exthdrs.ip6e_dest2)
 395                 optlen += exthdrs.ip6e_dest2->m_len;
 396
 397         /*
 398          * If there is at least one extension header,
 399          * separate IP6 header from the payload.
 400          */
 401         if (optlen && !hdrsplit) {
 402                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 403                         m = NULL;
 404                         goto freehdrs;
 405                 }
 406                 m = exthdrs.ip6e_ip6;
 407                 hdrsplit++;
 408         }
 409
 410         ip6 = mtod(m, struct ip6_hdr *);
 411
 412         /* adjust mbuf packet header length */
 413         m->m_pkthdr.len += optlen;
 414         plen = m->m_pkthdr.len - sizeof(*ip6);
 415
 416         /* If this is a jumbo payload, insert a jumbo payload option. */
 417         if (plen > IPV6_MAXPACKET) {
 418                 if (!hdrsplit) {
 419                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 420                                 m = NULL;
 421                                 goto freehdrs;
 422                         }
 423                         m = exthdrs.ip6e_ip6;
 424                         hdrsplit++;
 425                 }
 426                 /* adjust pointer */
 427                 ip6 = mtod(m, struct ip6_hdr *);
 428                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 429                         goto freehdrs;
 430                 ip6->ip6_plen = 0;
 431         } else
 432                 ip6->ip6_plen = htons(plen);
 433
 434         /*
 435          * Concatenate headers and fill in next header fields.
 436          * Here we have, on "m"
 437          *      IPv6 payload
 438          * and we insert headers accordingly.  Finally, we should be getting:
 439          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 440          *
 441          * during the header composing process, "m" points to IPv6 header.
 442          * "mprev" points to an extension header prior to esp.
 443          */
 444         u_char *nexthdrp = &ip6->ip6_nxt;
 445         mprev = m;
 446
 447         /*
 448          * we treat dest2 specially.  this makes IPsec processing
 449          * much easier.  the goal here is to make mprev point the
 450          * mbuf prior to dest2.
 451          *
 452          * result: IPv6 dest2 payload
 453          * m and mprev will point to IPv6 header.
 454          */
 455         if (exthdrs.ip6e_dest2) {
 456                 if (!hdrsplit)
 457                         panic("assumption failed: hdr not split");
 458                 exthdrs.ip6e_dest2->m_next = m->m_next;
 459                 m->m_next = exthdrs.ip6e_dest2;
 460                 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 461                 ip6->ip6_nxt = IPPROTO_DSTOPTS;
 462         }
 463
 464         /*
 465          * result: IPv6 hbh dest1 rthdr dest2 payload
 466          * m will point to IPv6 header.  mprev will point to the
 467          * extension header prior to dest2 (rthdr in the above case).
 468          */
 469         MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 470         MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 471                    IPPROTO_DSTOPTS);
 472         MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 473                    IPPROTO_ROUTING);
 474
 475         /*
 476          * If there is a routing header, discard the packet.
 477          */
 478         if (exthdrs.ip6e_rthdr) {
 479                  error = EINVAL;
 480                  goto bad;
 481         }
 482
 483         /* Source address validation */
 484         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 485             (flags & IPV6_UNSPECSRC) == 0) {
 486                 error = EOPNOTSUPP;
 487                 IP6STAT_INC(ip6s_badscope);
 488                 goto bad;
 489         }
 490         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 491                 error = EOPNOTSUPP;
 492                 IP6STAT_INC(ip6s_badscope);
 493                 goto bad;
 494         }
 495
 496         IP6STAT_INC(ip6s_localout);
 497
 498         /*
 499          * Route packet.
 500          */
 501         if (ro == NULL) {
 502                 ro = &ip6route;
 503                 bzero((caddr_t)ro, sizeof(*ro));
 504         }
 505         ro_pmtu = ro;
 506         if (opt && opt->ip6po_rthdr)
 507                 ro = &opt->ip6po_route;
 508         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 509         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 510 again:
 511         /*
 512          * if specified, try to fill in the traffic class field.
 513          * do not override if a non-zero value is already set.
 514          * we check the diffserv field and the ecn field separately.
 515          */
 516         if (opt && opt->ip6po_tclass >= 0) {
 517                 int mask = 0;
 518
 519                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 520                         mask |= 0xfc;
 521                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 522                         mask |= 0x03;
 523                 if (mask != 0)
 524                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 525         }
 526
 527         /* fill in or override the hop limit field, if necessary. */
 528         if (opt && opt->ip6po_hlim != -1)
 529                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 530         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 531                 if (im6o != NULL)
 532                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 533                 else
 534                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 535         }
 536         /*
 537          * Validate route against routing table additions;
 538          * a better/more specific route might have been added.
 539          * Make sure address family is set in route.
 540          */
 541         if (inp) {
 542                 ro->ro_dst.sin6_family = AF_INET6;
 543                 RT_VALIDATE((struct route *)ro, &inp->inp_rt_cookie, fibnum);
 544         }
 545         if (ro->ro_rt && fwd_tag == NULL && (ro->ro_rt->rt_flags & RTF_UP) &&
 546             ro->ro_dst.sin6_family == AF_INET6 &&
 547             IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 548                 rt = ro->ro_rt;
 549                 ifp = ro->ro_rt->rt_ifp;
 550         } else {
 551                 if (ro->ro_lle)
 552                         LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 553                 ro->ro_lle = NULL;
 554                 if (fwd_tag == NULL) {
 555                         bzero(&dst_sa, sizeof(dst_sa));
 556                         dst_sa.sin6_family = AF_INET6;
 557                         dst_sa.sin6_len = sizeof(dst_sa);
 558                         dst_sa.sin6_addr = ip6->ip6_dst;
 559                 }
 560                 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
 561                     &rt, fibnum);
 562                 if (error != 0) {
 563                         if (ifp != NULL)
 564                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 565                         goto bad;
 566                 }
 567         }
 568         if (rt == NULL) {
 569                 /*
 570                  * If in6_selectroute() does not return a route entry,
 571                  * dst may not have been updated.
 572                  */
 573                 *dst = dst_sa;  /* XXX */
 574         }
 575
 576         /*
 577          * then rt (for unicast) and ifp must be non-NULL valid values.
 578          */
 579         if ((flags & IPV6_FORWARDING) == 0) {
 580                 /* XXX: the FORWARDING flag can be set for mrouting. */
 581                 in6_ifstat_inc(ifp, ifs6_out_request);
 582         }
 583         if (rt != NULL) {
 584                 ia = (struct in6_ifaddr *)(rt->rt_ifa);
 585                 counter_u64_add(rt->rt_pksent, 1);
 586         }
 587
 588         /* Setup data structures for scope ID checks. */
 589         src0 = ip6->ip6_src;
 590         bzero(&src_sa, sizeof(src_sa));
 591         src_sa.sin6_family = AF_INET6;
 592         src_sa.sin6_len = sizeof(src_sa);
 593         src_sa.sin6_addr = ip6->ip6_src;
 594
 595         dst0 = ip6->ip6_dst;
 596         /* re-initialize to be sure */
 597         bzero(&dst_sa, sizeof(dst_sa));
 598         dst_sa.sin6_family = AF_INET6;
 599         dst_sa.sin6_len = sizeof(dst_sa);
 600         dst_sa.sin6_addr = ip6->ip6_dst;
 601
 602         /* Check for valid scope ID. */
 603         if (in6_setscope(&src0, ifp, &zone) == 0 &&
 604             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 605             in6_setscope(&dst0, ifp, &zone) == 0 &&
 606             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 607                 /*
 608                  * The outgoing interface is in the zone of the source
 609                  * and destination addresses.
 610                  *
 611                  * Because the loopback interface cannot receive
 612                  * packets with a different scope ID than its own,
 613                  * there is a trick is to pretend the outgoing packet
 614                  * was received by the real network interface, by
 615                  * setting "origifp" different from "ifp". This is
 616                  * only allowed when "ifp" is a loopback network
 617                  * interface. Refer to code in nd6_output_ifp() for
 618                  * more details.
 619                  */
 620                 origifp = ifp;
 621
 622                 /*
 623                  * We should use ia_ifp to support the case of sending
 624                  * packets to an address of our own.
 625                  */
 626                 if (ia != NULL && ia->ia_ifp)
 627                         ifp = ia->ia_ifp;
 628
 629         } else if ((ifp->if_flags & IFF_LOOPBACK) == 0 ||
 630             sa6_recoverscope(&src_sa) != 0 ||
 631             sa6_recoverscope(&dst_sa) != 0 ||
 632             dst_sa.sin6_scope_id == 0 ||
 633             (src_sa.sin6_scope_id != 0 &&
 634             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 635             (origifp = ifnet_byindex(dst_sa.sin6_scope_id)) == NULL) {
 636                 /*
 637                  * If the destination network interface is not a
 638                  * loopback interface, or the destination network
 639                  * address has no scope ID, or the source address has
 640                  * a scope ID set which is different from the
 641                  * destination address one, or there is no network
 642                  * interface representing this scope ID, the address
 643                  * pair is considered invalid.
 644                  */
 645                 IP6STAT_INC(ip6s_badscope);
 646                 in6_ifstat_inc(ifp, ifs6_out_discard);
 647                 if (error == 0)
 648                         error = EHOSTUNREACH; /* XXX */
 649                 goto bad;
 650         }
 651
 652         /* All scope ID checks are successful. */
 653
 654         if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 655                 if (opt && opt->ip6po_nextroute.ro_rt) {
 656                         /*
 657                          * The nexthop is explicitly specified by the
 658                          * application.  We assume the next hop is an IPv6
 659                          * address.
 660                          */
 661                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 662                 }
 663                 else if ((rt->rt_flags & RTF_GATEWAY))
 664                         dst = (struct sockaddr_in6 *)rt->rt_gateway;
 665         }
 666
 667         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 668                 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
 669         } else {
 670                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 671                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 672                 /*
 673                  * Confirm that the outgoing interface supports multicast.
 674                  */
 675                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 676                         IP6STAT_INC(ip6s_noroute);
 677                         in6_ifstat_inc(ifp, ifs6_out_discard);
 678                         error = ENETUNREACH;
 679                         goto bad;
 680                 }
 681                 if ((im6o == NULL && in6_mcast_loop) ||
 682                     (im6o && im6o->im6o_multicast_loop)) {
 683                         /*
 684                          * Loop back multicast datagram if not expressly
 685                          * forbidden to do so, even if we have not joined
 686                          * the address; protocols will filter it later,
 687                          * thus deferring a hash lookup and lock acquisition
 688                          * at the expense of an m_copym().
 689                          */
 690                         ip6_mloopback(ifp, m);
 691                 } else {
 692                         /*
 693                          * If we are acting as a multicast router, perform
 694                          * multicast forwarding as if the packet had just
 695                          * arrived on the interface to which we are about
 696                          * to send.  The multicast forwarding function
 697                          * recursively calls this function, using the
 698                          * IPV6_FORWARDING flag to prevent infinite recursion.
 699                          *
 700                          * Multicasts that are looped back by ip6_mloopback(),
 701                          * above, will be forwarded by the ip6_input() routine,
 702                          * if necessary.
 703                          */
 704                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 705                                 /*
 706                                  * XXX: ip6_mforward expects that rcvif is NULL
 707                                  * when it is called from the originating path.
 708                                  * However, it may not always be the case.
 709                                  */
 710                                 m->m_pkthdr.rcvif = NULL;
 711                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 712                                         m_freem(m);
 713                                         goto done;
 714                                 }
 715                         }
 716                 }
 717                 /*
 718                  * Multicasts with a hoplimit of zero may be looped back,
 719                  * above, but must not be transmitted on a network.
 720                  * Also, multicasts addressed to the loopback interface
 721                  * are not sent -- the above call to ip6_mloopback() will
 722                  * loop back a copy if this host actually belongs to the
 723                  * destination group on the loopback interface.
 724                  */
 725                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 726                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 727                         m_freem(m);
 728                         goto done;
 729                 }
 730         }
 731
 732         /*
 733          * Fill the outgoing inteface to tell the upper layer
 734          * to increment per-interface statistics.
 735          */
 736         if (ifpp)
 737                 *ifpp = ifp;
 738
 739         /* Determine path MTU. */
 740         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 741                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 742                 goto bad;
 743
 744         /*
 745          * The caller of this function may specify to use the minimum MTU
 746          * in some cases.
 747          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 748          * setting.  The logic is a bit complicated; by default, unicast
 749          * packets will follow path MTU while multicast packets will be sent at
 750          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 751          * including unicast ones will be sent at the minimum MTU.  Multicast
 752          * packets will always be sent at the minimum MTU unless
 753          * IP6PO_MINMTU_DISABLE is explicitly specified.
 754          * See RFC 3542 for more details.
 755          */
 756         if (mtu > IPV6_MMTU) {
 757                 if ((flags & IPV6_MINMTU))
 758                         mtu = IPV6_MMTU;
 759                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 760                         mtu = IPV6_MMTU;
 761                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 762                          (opt == NULL ||
 763                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 764                         mtu = IPV6_MMTU;
 765                 }
 766         }
 767
 768         /*
 769          * clear embedded scope identifiers if necessary.
 770          * in6_clearscope will touch the addresses only when necessary.
 771          */
 772         in6_clearscope(&ip6->ip6_src);
 773         in6_clearscope(&ip6->ip6_dst);
 774
 775         /*
 776          * If the outgoing packet contains a hop-by-hop options header,
 777          * it must be examined and processed even by the source node.
 778          * (RFC 2460, section 4.)
 779          */
 780         if (exthdrs.ip6e_hbh) {
 781                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 782                 u_int32_t dummy; /* XXX unused */
 783                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 784
 785 #ifdef DIAGNOSTIC
 786                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 787                         panic("ip6e_hbh is not contiguous");
 788 #endif
 789                 /*
 790                  *  XXX: if we have to send an ICMPv6 error to the sender,
 791                  *       we need the M_LOOP flag since icmp6_error() expects
 792                  *       the IPv6 and the hop-by-hop options header are
 793                  *       contiguous unless the flag is set.
 794                  */
 795                 m->m_flags |= M_LOOP;
 796                 m->m_pkthdr.rcvif = ifp;
 797                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 798                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 799                     &dummy, &plen) < 0) {
 800                         /* m was already freed at this point */
 801                         error = EINVAL;/* better error? */
 802                         goto done;
 803                 }
 804                 m->m_flags &= ~M_LOOP; /* XXX */
 805                 m->m_pkthdr.rcvif = NULL;
 806         }
 807
 808         /* Jump over all PFIL processing if hooks are not active. */
 809         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
 810                 goto passout;
 811
 812         odst = ip6->ip6_dst;
 813         /* Run through list of hooks for output packets. */
 814         switch (pfil_run_hooks(V_inet6_pfil_head, &m, ifp, PFIL_OUT, inp)) {
 815         case PFIL_PASS:
 816                 ip6 = mtod(m, struct ip6_hdr *);
 817                 break;
 818         case PFIL_DROPPED:
 819                 error = EPERM;
 820                 /* FALLTHROUGH */
 821         case PFIL_CONSUMED:
 822                 goto done;
 823         }
 824
 825         needfiblookup = 0;
 826         /* See if destination IP address was changed by packet filter. */
 827         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
 828                 m->m_flags |= M_SKIP_FIREWALL;
 829                 /* If destination is now ourself drop to ip6_input(). */
 830                 if (in6_localip(&ip6->ip6_dst)) {
 831                         m->m_flags |= M_FASTFWD_OURS;
 832                         if (m->m_pkthdr.rcvif == NULL)
 833                                 m->m_pkthdr.rcvif = V_loif;
 834                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 835                                 m->m_pkthdr.csum_flags |=
 836                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 837                                 m->m_pkthdr.csum_data = 0xffff;
 838                         }
 839 #ifdef SCTP
 840                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 841                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 842 #endif
 843                         error = netisr_queue(NETISR_IPV6, m);
 844                         goto done;
 845                 } else {
 846                         RO_INVALIDATE_CACHE(ro);
 847                         needfiblookup = 1; /* Redo the routing table lookup. */
 848                 }
 849         }
 850         /* See if fib was changed by packet filter. */
 851         if (fibnum != M_GETFIB(m)) {
 852                 m->m_flags |= M_SKIP_FIREWALL;
 853                 fibnum = M_GETFIB(m);
 854                 RO_INVALIDATE_CACHE(ro);
 855                 needfiblookup = 1;
 856         }
 857         if (needfiblookup)
 858                 goto again;
 859
 860         /* See if local, if yes, send it to netisr. */
 861         if (m->m_flags & M_FASTFWD_OURS) {
 862                 if (m->m_pkthdr.rcvif == NULL)
 863                         m->m_pkthdr.rcvif = V_loif;
 864                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 865                         m->m_pkthdr.csum_flags |=
 866                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 867                         m->m_pkthdr.csum_data = 0xffff;
 868                 }
 869 #ifdef SCTP
 870                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 871                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 872 #endif
 873                 error = netisr_queue(NETISR_IPV6, m);
 874                 goto done;
 875         }
 876         /* Or forward to some other address? */
 877         if ((m->m_flags & M_IP6_NEXTHOP) &&
 878             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 879                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 880                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
 881                 m->m_flags |= M_SKIP_FIREWALL;
 882                 m->m_flags &= ~M_IP6_NEXTHOP;
 883                 m_tag_delete(m, fwd_tag);
 884                 goto again;
 885         }
 886
 887 passout:
 888         /*
 889          * Send the packet to the outgoing interface.
 890          * If necessary, do IPv6 fragmentation before sending.
 891          *
 892          * the logic here is rather complex:
 893          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 894          * 1-a: send as is if tlen <= path mtu
 895          * 1-b: fragment if tlen > path mtu
 896          *
 897          * 2: if user asks us not to fragment (dontfrag == 1)
 898          * 2-a: send as is if tlen <= interface mtu
 899          * 2-b: error if tlen > interface mtu
 900          *
 901          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 902          *      always fragment
 903          *
 904          * 4: if dontfrag == 1 && alwaysfrag == 1
 905          *      error, as we cannot handle this conflicting request
 906          */
 907         sw_csum = m->m_pkthdr.csum_flags;
 908         if (!hdrsplit) {
 909                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
 910                 sw_csum &= ~ifp->if_hwassist;
 911         } else
 912                 tso = 0;
 913         /*
 914          * If we added extension headers, we will not do TSO and calculate the
 915          * checksums ourselves for now.
 916          * XXX-BZ  Need a framework to know when the NIC can handle it, even
 917          * with ext. hdrs.
 918          */
 919         if (sw_csum & CSUM_DELAY_DATA_IPV6) {
 920                 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
 921                 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
 922         }
 923 #ifdef SCTP
 924         if (sw_csum & CSUM_SCTP_IPV6) {
 925                 sw_csum &= ~CSUM_SCTP_IPV6;
 926                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
 927         }
 928 #endif
 929         m->m_pkthdr.csum_flags &= ifp->if_hwassist;
 930         tlen = m->m_pkthdr.len;
 931
 932         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
 933                 dontfrag = 1;
 934         else
 935                 dontfrag = 0;
 936         if (dontfrag && alwaysfrag) {   /* case 4 */
 937                 /* conflicting request - can't transmit */
 938                 error = EMSGSIZE;
 939                 goto bad;
 940         }
 941         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* case 2-b */
 942                 /*
 943                  * Even if the DONTFRAG option is specified, we cannot send the
 944                  * packet when the data length is larger than the MTU of the
 945                  * outgoing interface.
 946                  * Notify the error by sending IPV6_PATHMTU ancillary data if
 947                  * application wanted to know the MTU value. Also return an
 948                  * error code (this is not described in the API spec).
 949                  */
 950                 if (inp != NULL)
 951                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
 952                 error = EMSGSIZE;
 953                 goto bad;
 954         }
 955
 956         /*
 957          * transmit packet without fragmentation
 958          */
 959         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
 960                 struct in6_ifaddr *ia6;
 961
 962                 ip6 = mtod(m, struct ip6_hdr *);
 963                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
 964                 if (ia6) {
 965                         /* Record statistics for this interface address. */
 966                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
 967                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
 968                             m->m_pkthdr.len);
 969                         ifa_free(&ia6->ia_ifa);
 970                 }
 971 #ifdef RATELIMIT
 972                 if (inp != NULL) {
 973                         if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 974                                 in_pcboutput_txrtlmt(inp, ifp, m);
 975                         /* stamp send tag on mbuf */
 976                         m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 977                 } else {
 978                         m->m_pkthdr.snd_tag = NULL;
 979                 }
 980 #endif
 981                 error = nd6_output_ifp(ifp, origifp, m, dst,
 982                     (struct route *)ro);
 983 #ifdef RATELIMIT
 984                 /* check for route change */
 985                 if (error == EAGAIN)
 986                         in_pcboutput_eagain(inp);
 987 #endif
 988                 goto done;
 989         }
 990
 991         /*
 992          * try to fragment the packet.  case 1-b and 3
 993          */
 994         if (mtu < IPV6_MMTU) {
 995                 /* path MTU cannot be less than IPV6_MMTU */
 996                 error = EMSGSIZE;
 997                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 998                 goto bad;
 999         } else if (ip6->ip6_plen == 0) {
1000                 /* jumbo payload cannot be fragmented */
1001                 error = EMSGSIZE;
1002                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1003                 goto bad;
1004         } else {
1005                 u_char nextproto;
1006
1007                 /*
1008                  * Too large for the destination or interface;
1009                  * fragment if possible.
1010                  * Must be able to put at least 8 bytes per fragment.
1011                  */
1012                 hlen = unfragpartlen;
1013                 if (mtu > IPV6_MAXPACKET)
1014                         mtu = IPV6_MAXPACKET;
1015
1016                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
1017                 if (len < 8) {
1018                         error = EMSGSIZE;
1019                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1020                         goto bad;
1021                 }
1022
1023                 /*
1024                  * If the interface will not calculate checksums on
1025                  * fragmented packets, then do it here.
1026                  * XXX-BZ handle the hw offloading case.  Need flags.
1027                  */
1028                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1029                         in6_delayed_cksum(m, plen, hlen);
1030                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
1031                 }
1032 #ifdef SCTP
1033                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
1034                         sctp_delayed_cksum(m, hlen);
1035                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
1036                 }
1037 #endif
1038                 /*
1039                  * Change the next header field of the last header in the
1040                  * unfragmentable part.
1041                  */
1042                 if (exthdrs.ip6e_rthdr) {
1043                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1044                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1045                 } else if (exthdrs.ip6e_dest1) {
1046                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1047                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1048                 } else if (exthdrs.ip6e_hbh) {
1049                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1050                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1051                 } else {
1052                         nextproto = ip6->ip6_nxt;
1053                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1054                 }
1055
1056                 /*
1057                  * Loop through length of segment after first fragment,
1058                  * make new header and copy data of each part and link onto
1059                  * chain.
1060                  */
1061                 m0 = m;
1062                 id = htonl(ip6_randomid());
1063                 if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
1064                         goto sendorfree;
1065
1066                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1067         }
1068
1069         /*
1070          * Remove leading garbages.
1071          */
1072 sendorfree:
1073         m = m0->m_nextpkt;
1074         m0->m_nextpkt = 0;
1075         m_freem(m0);
1076         for (; m; m = m0) {
1077                 m0 = m->m_nextpkt;
1078                 m->m_nextpkt = 0;
1079                 if (error == 0) {
1080                         /* Record statistics for this interface address. */
1081                         if (ia) {
1082                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1083                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1084                                     m->m_pkthdr.len);
1085                         }
1086 #ifdef RATELIMIT
1087                         if (inp != NULL) {
1088                                 if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
1089                                         in_pcboutput_txrtlmt(inp, ifp, m);
1090                                 /* stamp send tag on mbuf */
1091                                 m->m_pkthdr.snd_tag = inp->inp_snd_tag;
1092                         } else {
1093                                 m->m_pkthdr.snd_tag = NULL;
1094                         }
1095 #endif
1096                         error = nd6_output_ifp(ifp, origifp, m, dst,
1097                             (struct route *)ro);
1098 #ifdef RATELIMIT
1099                         /* check for route change */
1100                         if (error == EAGAIN)
1101                                 in_pcboutput_eagain(inp);
1102 #endif
1103                 } else
1104                         m_freem(m);
1105         }
1106
1107         if (error == 0)
1108                 IP6STAT_INC(ip6s_fragmented);
1109
1110 done:
1111         if (ro == &ip6route)
1112                 RO_RTFREE(ro);
1113         return (error);
1114
1115 freehdrs:
1116         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1117         m_freem(exthdrs.ip6e_dest1);
1118         m_freem(exthdrs.ip6e_rthdr);
1119         m_freem(exthdrs.ip6e_dest2);
1120         /* FALLTHROUGH */
1121 bad:
1122         if (m)
1123                 m_freem(m);
1124         goto done;
1125 }
1126
1127 static int
1128 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1129 {
1130         struct mbuf *m;
1131
1132         if (hlen > MCLBYTES)
1133                 return (ENOBUFS); /* XXX */
1134
1135         if (hlen > MLEN)
1136                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1137         else
1138                 m = m_get(M_NOWAIT, MT_DATA);
1139         if (m == NULL)
1140                 return (ENOBUFS);
1141         m->m_len = hlen;
1142         if (hdr)
1143                 bcopy(hdr, mtod(m, caddr_t), hlen);
1144
1145         *mp = m;
1146         return (0);
1147 }
1148
1149 /*
1150  * Insert jumbo payload option.
1151  */
1152 static int
1153 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1154 {
1155         struct mbuf *mopt;
1156         u_char *optbuf;
1157         u_int32_t v;
1158
1159 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1160
1161         /*
1162          * If there is no hop-by-hop options header, allocate new one.
1163          * If there is one but it doesn't have enough space to store the
1164          * jumbo payload option, allocate a cluster to store the whole options.
1165          * Otherwise, use it to store the options.
1166          */
1167         if (exthdrs->ip6e_hbh == NULL) {
1168                 mopt = m_get(M_NOWAIT, MT_DATA);
1169                 if (mopt == NULL)
1170                         return (ENOBUFS);
1171                 mopt->m_len = JUMBOOPTLEN;
1172                 optbuf = mtod(mopt, u_char *);
1173                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1174                 exthdrs->ip6e_hbh = mopt;
1175         } else {
1176                 struct ip6_hbh *hbh;
1177
1178                 mopt = exthdrs->ip6e_hbh;
1179                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1180                         /*
1181                          * XXX assumption:
1182                          * - exthdrs->ip6e_hbh is not referenced from places
1183                          *   other than exthdrs.
1184                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1185                          */
1186                         int oldoptlen = mopt->m_len;
1187                         struct mbuf *n;
1188
1189                         /*
1190                          * XXX: give up if the whole (new) hbh header does
1191                          * not fit even in an mbuf cluster.
1192                          */
1193                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1194                                 return (ENOBUFS);
1195
1196                         /*
1197                          * As a consequence, we must always prepare a cluster
1198                          * at this point.
1199                          */
1200                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1201                         if (n == NULL)
1202                                 return (ENOBUFS);
1203                         n->m_len = oldoptlen + JUMBOOPTLEN;
1204                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1205                             oldoptlen);
1206                         optbuf = mtod(n, caddr_t) + oldoptlen;
1207                         m_freem(mopt);
1208                         mopt = exthdrs->ip6e_hbh = n;
1209                 } else {
1210                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1211                         mopt->m_len += JUMBOOPTLEN;
1212                 }
1213                 optbuf[0] = IP6OPT_PADN;
1214                 optbuf[1] = 1;
1215
1216                 /*
1217                  * Adjust the header length according to the pad and
1218                  * the jumbo payload option.
1219                  */
1220                 hbh = mtod(mopt, struct ip6_hbh *);
1221                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1222         }
1223
1224         /* fill in the option. */
1225         optbuf[2] = IP6OPT_JUMBO;
1226         optbuf[3] = 4;
1227         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1228         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1229
1230         /* finally, adjust the packet header length */
1231         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1232
1233         return (0);
1234 #undef JUMBOOPTLEN
1235 }
1236
1237 /*
1238  * Insert fragment header and copy unfragmentable header portions.
1239  */
1240 static int
1241 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1242     struct ip6_frag **frghdrp)
1243 {
1244         struct mbuf *n, *mlast;
1245
1246         if (hlen > sizeof(struct ip6_hdr)) {
1247                 n = m_copym(m0, sizeof(struct ip6_hdr),
1248                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1249                 if (n == NULL)
1250                         return (ENOBUFS);
1251                 m->m_next = n;
1252         } else
1253                 n = m;
1254
1255         /* Search for the last mbuf of unfragmentable part. */
1256         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1257                 ;
1258
1259         if (M_WRITABLE(mlast) &&
1260             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1261                 /* use the trailing space of the last mbuf for the fragment hdr */
1262                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1263                     mlast->m_len);
1264                 mlast->m_len += sizeof(struct ip6_frag);
1265                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1266         } else {
1267                 /* allocate a new mbuf for the fragment header */
1268                 struct mbuf *mfrg;
1269
1270                 mfrg = m_get(M_NOWAIT, MT_DATA);
1271                 if (mfrg == NULL)
1272                         return (ENOBUFS);
1273                 mfrg->m_len = sizeof(struct ip6_frag);
1274                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1275                 mlast->m_next = mfrg;
1276         }
1277
1278         return (0);
1279 }
1280
1281 /*
1282  * Calculates IPv6 path mtu for destination @dst.
1283  * Resulting MTU is stored in @mtup.
1284  *
1285  * Returns 0 on success.
1286  */
1287 static int
1288 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1289 {
1290         struct nhop6_extended nh6;
1291         struct in6_addr kdst;
1292         uint32_t scopeid;
1293         struct ifnet *ifp;
1294         u_long mtu;
1295         int error;
1296
1297         in6_splitscope(dst, &kdst, &scopeid);
1298         if (fib6_lookup_nh_ext(fibnum, &kdst, scopeid, NHR_REF, 0, &nh6) != 0)
1299                 return (EHOSTUNREACH);
1300
1301         ifp = nh6.nh_ifp;
1302         mtu = nh6.nh_mtu;
1303
1304         error = ip6_calcmtu(ifp, dst, mtu, mtup, NULL, 0);
1305         fib6_free_nh_ext(fibnum, &nh6);
1306
1307         return (error);
1308 }
1309
1310 /*
1311  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1312  * and cached data in @ro_pmtu.
1313  * MTU from (successful) route lookup is saved (along with dst)
1314  * inside @ro_pmtu to avoid subsequent route lookups after packet
1315  * filter processing.
1316  *
1317  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1318  * Returns 0 on success.
1319  */
1320 static int
1321 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1322     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1323     int *alwaysfragp, u_int fibnum, u_int proto)
1324 {
1325         struct nhop6_basic nh6;
1326         struct in6_addr kdst;
1327         uint32_t scopeid;
1328         struct sockaddr_in6 *sa6_dst;
1329         u_long mtu;
1330
1331         mtu = 0;
1332         if (do_lookup) {
1333
1334                 /*
1335                  * Here ro_pmtu has final destination address, while
1336                  * ro might represent immediate destination.
1337                  * Use ro_pmtu destination since mtu might differ.
1338                  */
1339                 sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1340                 if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1341                         ro_pmtu->ro_mtu = 0;
1342
1343                 if (ro_pmtu->ro_mtu == 0) {
1344                         bzero(sa6_dst, sizeof(*sa6_dst));
1345                         sa6_dst->sin6_family = AF_INET6;
1346                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1347                         sa6_dst->sin6_addr = *dst;
1348
1349                         in6_splitscope(dst, &kdst, &scopeid);
1350                         if (fib6_lookup_nh_basic(fibnum, &kdst, scopeid, 0, 0,
1351                             &nh6) == 0)
1352                                 ro_pmtu->ro_mtu = nh6.nh_mtu;
1353                 }
1354
1355                 mtu = ro_pmtu->ro_mtu;
1356         }
1357
1358         if (ro_pmtu->ro_rt)
1359                 mtu = ro_pmtu->ro_rt->rt_mtu;
1360
1361         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1362 }
1363
1364 /*
1365  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1366  * hostcache data for @dst.
1367  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1368  *
1369  * Returns 0 on success.
1370  */
1371 static int
1372 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1373     u_long *mtup, int *alwaysfragp, u_int proto)
1374 {
1375         u_long mtu = 0;
1376         int alwaysfrag = 0;
1377         int error = 0;
1378
1379         if (rt_mtu > 0) {
1380                 u_int32_t ifmtu;
1381                 struct in_conninfo inc;
1382
1383                 bzero(&inc, sizeof(inc));
1384                 inc.inc_flags |= INC_ISIPV6;
1385                 inc.inc6_faddr = *dst;
1386
1387                 ifmtu = IN6_LINKMTU(ifp);
1388
1389                 /* TCP is known to react to pmtu changes so skip hc */
1390                 if (proto != IPPROTO_TCP)
1391                         mtu = tcp_hc_getmtu(&inc);
1392
1393                 if (mtu)
1394                         mtu = min(mtu, rt_mtu);
1395                 else
1396                         mtu = rt_mtu;
1397                 if (mtu == 0)
1398                         mtu = ifmtu;
1399                 else if (mtu < IPV6_MMTU) {
1400                         /*
1401                          * RFC2460 section 5, last paragraph:
1402                          * if we record ICMPv6 too big message with
1403                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1404                          * or smaller, with framgent header attached.
1405                          * (fragment header is needed regardless from the
1406                          * packet size, for translators to identify packets)
1407                          */
1408                         alwaysfrag = 1;
1409                         mtu = IPV6_MMTU;
1410                 }
1411         } else if (ifp) {
1412                 mtu = IN6_LINKMTU(ifp);
1413         } else
1414                 error = EHOSTUNREACH; /* XXX */
1415
1416         *mtup = mtu;
1417         if (alwaysfragp)
1418                 *alwaysfragp = alwaysfrag;
1419         return (error);
1420 }
1421
1422 /*
1423  * IP6 socket option processing.
1424  */
1425 int
1426 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1427 {
1428         int optdatalen, uproto;
1429         void *optdata;
1430         struct inpcb *in6p = sotoinpcb(so);
1431         int error, optval;
1432         int level, op, optname;
1433         int optlen;
1434         struct thread *td;
1435 #ifdef  RSS
1436         uint32_t rss_bucket;
1437         int retval;
1438 #endif
1439
1440 /*
1441  * Don't use more than a quarter of mbuf clusters.  N.B.:
1442  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1443  * on LP64 architectures, so cast to u_long to avoid undefined
1444  * behavior.  ILP32 architectures cannot have nmbclusters
1445  * large enough to overflow for other reasons.
1446  */
1447 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1448
1449         level = sopt->sopt_level;
1450         op = sopt->sopt_dir;
1451         optname = sopt->sopt_name;
1452         optlen = sopt->sopt_valsize;
1453         td = sopt->sopt_td;
1454         error = 0;
1455         optval = 0;
1456         uproto = (int)so->so_proto->pr_protocol;
1457
1458         if (level != IPPROTO_IPV6) {
1459                 error = EINVAL;
1460
1461                 if (sopt->sopt_level == SOL_SOCKET &&
1462                     sopt->sopt_dir == SOPT_SET) {
1463                         switch (sopt->sopt_name) {
1464                         case SO_REUSEADDR:
1465                                 INP_WLOCK(in6p);
1466                                 if ((so->so_options & SO_REUSEADDR) != 0)
1467                                         in6p->inp_flags2 |= INP_REUSEADDR;
1468                                 else
1469                                         in6p->inp_flags2 &= ~INP_REUSEADDR;
1470                                 INP_WUNLOCK(in6p);
1471                                 error = 0;
1472                                 break;
1473                         case SO_REUSEPORT:
1474                                 INP_WLOCK(in6p);
1475                                 if ((so->so_options & SO_REUSEPORT) != 0)
1476                                         in6p->inp_flags2 |= INP_REUSEPORT;
1477                                 else
1478                                         in6p->inp_flags2 &= ~INP_REUSEPORT;
1479                                 INP_WUNLOCK(in6p);
1480                                 error = 0;
1481                                 break;
1482                         case SO_REUSEPORT_LB:
1483                                 INP_WLOCK(in6p);
1484                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1485                                         in6p->inp_flags2 |= INP_REUSEPORT_LB;
1486                                 else
1487                                         in6p->inp_flags2 &= ~INP_REUSEPORT_LB;
1488                                 INP_WUNLOCK(in6p);
1489                                 error = 0;
1490                                 break;
1491                         case SO_SETFIB:
1492                                 INP_WLOCK(in6p);
1493                                 in6p->inp_inc.inc_fibnum = so->so_fibnum;
1494                                 INP_WUNLOCK(in6p);
1495                                 error = 0;
1496                                 break;
1497                         case SO_MAX_PACING_RATE:
1498 #ifdef RATELIMIT
1499                                 INP_WLOCK(in6p);
1500                                 in6p->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1501                                 INP_WUNLOCK(in6p);
1502                                 error = 0;
1503 #else
1504                                 error = EOPNOTSUPP;
1505 #endif
1506                                 break;
1507                         default:
1508                                 break;
1509                         }
1510                 }
1511         } else {                /* level == IPPROTO_IPV6 */
1512                 switch (op) {
1513
1514                 case SOPT_SET:
1515                         switch (optname) {
1516                         case IPV6_2292PKTOPTIONS:
1517 #ifdef IPV6_PKTOPTIONS
1518                         case IPV6_PKTOPTIONS:
1519 #endif
1520                         {
1521                                 struct mbuf *m;
1522
1523                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1524                                         printf("ip6_ctloutput: mbuf limit hit\n");
1525                                         error = ENOBUFS;
1526                                         break;
1527                                 }
1528
1529                                 error = soopt_getm(sopt, &m); /* XXX */
1530                                 if (error != 0)
1531                                         break;
1532                                 error = soopt_mcopyin(sopt, m); /* XXX */
1533                                 if (error != 0)
1534                                         break;
1535                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1536                                                     m, so, sopt);
1537                                 m_freem(m); /* XXX */
1538                                 break;
1539                         }
1540
1541                         /*
1542                          * Use of some Hop-by-Hop options or some
1543                          * Destination options, might require special
1544                          * privilege.  That is, normal applications
1545                          * (without special privilege) might be forbidden
1546                          * from setting certain options in outgoing packets,
1547                          * and might never see certain options in received
1548                          * packets. [RFC 2292 Section 6]
1549                          * KAME specific note:
1550                          *  KAME prevents non-privileged users from sending or
1551                          *  receiving ANY hbh/dst options in order to avoid
1552                          *  overhead of parsing options in the kernel.
1553                          */
1554                         case IPV6_RECVHOPOPTS:
1555                         case IPV6_RECVDSTOPTS:
1556                         case IPV6_RECVRTHDRDSTOPTS:
1557                                 if (td != NULL) {
1558                                         error = priv_check(td,
1559                                             PRIV_NETINET_SETHDROPTS);
1560                                         if (error)
1561                                                 break;
1562                                 }
1563                                 /* FALLTHROUGH */
1564                         case IPV6_UNICAST_HOPS:
1565                         case IPV6_HOPLIMIT:
1566
1567                         case IPV6_RECVPKTINFO:
1568                         case IPV6_RECVHOPLIMIT:
1569                         case IPV6_RECVRTHDR:
1570                         case IPV6_RECVPATHMTU:
1571                         case IPV6_RECVTCLASS:
1572                         case IPV6_RECVFLOWID:
1573 #ifdef  RSS
1574                         case IPV6_RECVRSSBUCKETID:
1575 #endif
1576                         case IPV6_V6ONLY:
1577                         case IPV6_AUTOFLOWLABEL:
1578                         case IPV6_ORIGDSTADDR:
1579                         case IPV6_BINDANY:
1580                         case IPV6_BINDMULTI:
1581 #ifdef  RSS
1582                         case IPV6_RSS_LISTEN_BUCKET:
1583 #endif
1584                                 if (optname == IPV6_BINDANY && td != NULL) {
1585                                         error = priv_check(td,
1586                                             PRIV_NETINET_BINDANY);
1587                                         if (error)
1588                                                 break;
1589                                 }
1590
1591                                 if (optlen != sizeof(int)) {
1592                                         error = EINVAL;
1593                                         break;
1594                                 }
1595                                 error = sooptcopyin(sopt, &optval,
1596                                         sizeof optval, sizeof optval);
1597                                 if (error)
1598                                         break;
1599                                 switch (optname) {
1600
1601                                 case IPV6_UNICAST_HOPS:
1602                                         if (optval < -1 || optval >= 256)
1603                                                 error = EINVAL;
1604                                         else {
1605                                                 /* -1 = kernel default */
1606                                                 in6p->in6p_hops = optval;
1607                                                 if ((in6p->inp_vflag &
1608                                                      INP_IPV4) != 0)
1609                                                         in6p->inp_ip_ttl = optval;
1610                                         }
1611                                         break;
1612 #define OPTSET(bit) \
1613 do { \
1614         INP_WLOCK(in6p); \
1615         if (optval) \
1616                 in6p->inp_flags |= (bit); \
1617         else \
1618                 in6p->inp_flags &= ~(bit); \
1619         INP_WUNLOCK(in6p); \
1620 } while (/*CONSTCOND*/ 0)
1621 #define OPTSET2292(bit) \
1622 do { \
1623         INP_WLOCK(in6p); \
1624         in6p->inp_flags |= IN6P_RFC2292; \
1625         if (optval) \
1626                 in6p->inp_flags |= (bit); \
1627         else \
1628                 in6p->inp_flags &= ~(bit); \
1629         INP_WUNLOCK(in6p); \
1630 } while (/*CONSTCOND*/ 0)
1631 #define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0)
1632
1633 #define OPTSET2_N(bit, val) do {                                        \
1634         if (val)                                                        \
1635                 in6p->inp_flags2 |= bit;                                \
1636         else                                                            \
1637                 in6p->inp_flags2 &= ~bit;                               \
1638 } while (0)
1639 #define OPTSET2(bit, val) do {                                          \
1640         INP_WLOCK(in6p);                                                \
1641         OPTSET2_N(bit, val);                                            \
1642         INP_WUNLOCK(in6p);                                              \
1643 } while (0)
1644 #define OPTBIT2(bit) (in6p->inp_flags2 & (bit) ? 1 : 0)
1645 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1646 do {                                                                    \
1647         INP_WLOCK(in6p);                                                \
1648         if (OPTBIT(IN6P_RFC2292)) {                                     \
1649                 error = EINVAL;                                         \
1650         } else {                                                        \
1651                 if (optval)                                             \
1652                         in6p->inp_flags |= (bit);                       \
1653                 else                                                    \
1654                         in6p->inp_flags &= ~(bit);                      \
1655         }                                                               \
1656         INP_WUNLOCK(in6p);                                              \
1657 } while (/*CONSTCOND*/ 0)
1658
1659                                 case IPV6_RECVPKTINFO:
1660                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1661                                         break;
1662
1663                                 case IPV6_HOPLIMIT:
1664                                 {
1665                                         struct ip6_pktopts **optp;
1666
1667                                         /* cannot mix with RFC2292 */
1668                                         if (OPTBIT(IN6P_RFC2292)) {
1669                                                 error = EINVAL;
1670                                                 break;
1671                                         }
1672                                         INP_WLOCK(in6p);
1673                                         if (in6p->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1674                                                 INP_WUNLOCK(in6p);
1675                                                 return (ECONNRESET);
1676                                         }
1677                                         optp = &in6p->in6p_outputopts;
1678                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1679                                             (u_char *)&optval, sizeof(optval),
1680                                             optp, (td != NULL) ? td->td_ucred :
1681                                             NULL, uproto);
1682                                         INP_WUNLOCK(in6p);
1683                                         break;
1684                                 }
1685
1686                                 case IPV6_RECVHOPLIMIT:
1687                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1688                                         break;
1689
1690                                 case IPV6_RECVHOPOPTS:
1691                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1692                                         break;
1693
1694                                 case IPV6_RECVDSTOPTS:
1695                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1696                                         break;
1697
1698                                 case IPV6_RECVRTHDRDSTOPTS:
1699                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1700                                         break;
1701
1702                                 case IPV6_RECVRTHDR:
1703                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1704                                         break;
1705
1706                                 case IPV6_RECVPATHMTU:
1707                                         /*
1708                                          * We ignore this option for TCP
1709                                          * sockets.
1710                                          * (RFC3542 leaves this case
1711                                          * unspecified.)
1712                                          */
1713                                         if (uproto != IPPROTO_TCP)
1714                                                 OPTSET(IN6P_MTU);
1715                                         break;
1716
1717                                 case IPV6_RECVFLOWID:
1718                                         OPTSET2(INP_RECVFLOWID, optval);
1719                                         break;
1720
1721 #ifdef  RSS
1722                                 case IPV6_RECVRSSBUCKETID:
1723                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1724                                         break;
1725 #endif
1726
1727                                 case IPV6_V6ONLY:
1728                                         /*
1729                                          * make setsockopt(IPV6_V6ONLY)
1730                                          * available only prior to bind(2).
1731                                          * see ipng mailing list, Jun 22 2001.
1732                                          */
1733                                         if (in6p->inp_lport ||
1734                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
1735                                                 error = EINVAL;
1736                                                 break;
1737                                         }
1738                                         OPTSET(IN6P_IPV6_V6ONLY);
1739                                         if (optval)
1740                                                 in6p->inp_vflag &= ~INP_IPV4;
1741                                         else
1742                                                 in6p->inp_vflag |= INP_IPV4;
1743                                         break;
1744                                 case IPV6_RECVTCLASS:
1745                                         /* cannot mix with RFC2292 XXX */
1746                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1747                                         break;
1748                                 case IPV6_AUTOFLOWLABEL:
1749                                         OPTSET(IN6P_AUTOFLOWLABEL);
1750                                         break;
1751
1752                                 case IPV6_ORIGDSTADDR:
1753                                         OPTSET2(INP_ORIGDSTADDR, optval);
1754                                         break;
1755                                 case IPV6_BINDANY:
1756                                         OPTSET(INP_BINDANY);
1757                                         break;
1758
1759                                 case IPV6_BINDMULTI:
1760                                         OPTSET2(INP_BINDMULTI, optval);
1761                                         break;
1762 #ifdef  RSS
1763                                 case IPV6_RSS_LISTEN_BUCKET:
1764                                         if ((optval >= 0) &&
1765                                             (optval < rss_getnumbuckets())) {
1766                                                 INP_WLOCK(in6p);
1767                                                 in6p->inp_rss_listen_bucket = optval;
1768                                                 OPTSET2_N(INP_RSS_BUCKET_SET, 1);
1769                                                 INP_WUNLOCK(in6p);
1770                                         } else {
1771                                                 error = EINVAL;
1772                                         }
1773                                         break;
1774 #endif
1775                                 }
1776                                 break;
1777
1778                         case IPV6_TCLASS:
1779                         case IPV6_DONTFRAG:
1780                         case IPV6_USE_MIN_MTU:
1781                         case IPV6_PREFER_TEMPADDR:
1782                                 if (optlen != sizeof(optval)) {
1783                                         error = EINVAL;
1784                                         break;
1785                                 }
1786                                 error = sooptcopyin(sopt, &optval,
1787                                         sizeof optval, sizeof optval);
1788                                 if (error)
1789                                         break;
1790                                 {
1791                                         struct ip6_pktopts **optp;
1792                                         INP_WLOCK(in6p);
1793                                         if (in6p->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1794                                                 INP_WUNLOCK(in6p);
1795                                                 return (ECONNRESET);
1796                                         }
1797                                         optp = &in6p->in6p_outputopts;
1798                                         error = ip6_pcbopt(optname,
1799                                             (u_char *)&optval, sizeof(optval),
1800                                             optp, (td != NULL) ? td->td_ucred :
1801                                             NULL, uproto);
1802                                         INP_WUNLOCK(in6p);
1803                                         break;
1804                                 }
1805
1806                         case IPV6_2292PKTINFO:
1807                         case IPV6_2292HOPLIMIT:
1808                         case IPV6_2292HOPOPTS:
1809                         case IPV6_2292DSTOPTS:
1810                         case IPV6_2292RTHDR:
1811                                 /* RFC 2292 */
1812                                 if (optlen != sizeof(int)) {
1813                                         error = EINVAL;
1814                                         break;
1815                                 }
1816                                 error = sooptcopyin(sopt, &optval,
1817                                         sizeof optval, sizeof optval);
1818                                 if (error)
1819                                         break;
1820                                 switch (optname) {
1821                                 case IPV6_2292PKTINFO:
1822                                         OPTSET2292(IN6P_PKTINFO);
1823                                         break;
1824                                 case IPV6_2292HOPLIMIT:
1825                                         OPTSET2292(IN6P_HOPLIMIT);
1826                                         break;
1827                                 case IPV6_2292HOPOPTS:
1828                                         /*
1829                                          * Check super-user privilege.
1830                                          * See comments for IPV6_RECVHOPOPTS.
1831                                          */
1832                                         if (td != NULL) {
1833                                                 error = priv_check(td,
1834                                                     PRIV_NETINET_SETHDROPTS);
1835                                                 if (error)
1836                                                         return (error);
1837                                         }
1838                                         OPTSET2292(IN6P_HOPOPTS);
1839                                         break;
1840                                 case IPV6_2292DSTOPTS:
1841                                         if (td != NULL) {
1842                                                 error = priv_check(td,
1843                                                     PRIV_NETINET_SETHDROPTS);
1844                                                 if (error)
1845                                                         return (error);
1846                                         }
1847                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1848                                         break;
1849                                 case IPV6_2292RTHDR:
1850                                         OPTSET2292(IN6P_RTHDR);
1851                                         break;
1852                                 }
1853                                 break;
1854                         case IPV6_PKTINFO:
1855                         case IPV6_HOPOPTS:
1856                         case IPV6_RTHDR:
1857                         case IPV6_DSTOPTS:
1858                         case IPV6_RTHDRDSTOPTS:
1859                         case IPV6_NEXTHOP:
1860                         {
1861                                 /* new advanced API (RFC3542) */
1862                                 u_char *optbuf;
1863                                 u_char optbuf_storage[MCLBYTES];
1864                                 int optlen;
1865                                 struct ip6_pktopts **optp;
1866
1867                                 /* cannot mix with RFC2292 */
1868                                 if (OPTBIT(IN6P_RFC2292)) {
1869                                         error = EINVAL;
1870                                         break;
1871                                 }
1872
1873                                 /*
1874                                  * We only ensure valsize is not too large
1875                                  * here.  Further validation will be done
1876                                  * later.
1877                                  */
1878                                 error = sooptcopyin(sopt, optbuf_storage,
1879                                     sizeof(optbuf_storage), 0);
1880                                 if (error)
1881                                         break;
1882                                 optlen = sopt->sopt_valsize;
1883                                 optbuf = optbuf_storage;
1884                                 INP_WLOCK(in6p);
1885                                 if (in6p->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1886                                         INP_WUNLOCK(in6p);
1887                                         return (ECONNRESET);
1888                                 }
1889                                 optp = &in6p->in6p_outputopts;
1890                                 error = ip6_pcbopt(optname, optbuf, optlen,
1891                                     optp, (td != NULL) ? td->td_ucred : NULL,
1892                                     uproto);
1893                                 INP_WUNLOCK(in6p);
1894                                 break;
1895                         }
1896 #undef OPTSET
1897
1898                         case IPV6_MULTICAST_IF:
1899                         case IPV6_MULTICAST_HOPS:
1900                         case IPV6_MULTICAST_LOOP:
1901                         case IPV6_JOIN_GROUP:
1902                         case IPV6_LEAVE_GROUP:
1903                         case IPV6_MSFILTER:
1904                         case MCAST_BLOCK_SOURCE:
1905                         case MCAST_UNBLOCK_SOURCE:
1906                         case MCAST_JOIN_GROUP:
1907                         case MCAST_LEAVE_GROUP:
1908                         case MCAST_JOIN_SOURCE_GROUP:
1909                         case MCAST_LEAVE_SOURCE_GROUP:
1910                                 error = ip6_setmoptions(in6p, sopt);
1911                                 break;
1912
1913                         case IPV6_PORTRANGE:
1914                                 error = sooptcopyin(sopt, &optval,
1915                                     sizeof optval, sizeof optval);
1916                                 if (error)
1917                                         break;
1918
1919                                 INP_WLOCK(in6p);
1920                                 switch (optval) {
1921                                 case IPV6_PORTRANGE_DEFAULT:
1922                                         in6p->inp_flags &= ~(INP_LOWPORT);
1923                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1924                                         break;
1925
1926                                 case IPV6_PORTRANGE_HIGH:
1927                                         in6p->inp_flags &= ~(INP_LOWPORT);
1928                                         in6p->inp_flags |= INP_HIGHPORT;
1929                                         break;
1930
1931                                 case IPV6_PORTRANGE_LOW:
1932                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1933                                         in6p->inp_flags |= INP_LOWPORT;
1934                                         break;
1935
1936                                 default:
1937                                         error = EINVAL;
1938                                         break;
1939                                 }
1940                                 INP_WUNLOCK(in6p);
1941                                 break;
1942
1943 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1944                         case IPV6_IPSEC_POLICY:
1945                                 if (IPSEC_ENABLED(ipv6)) {
1946                                         error = IPSEC_PCBCTL(ipv6, in6p, sopt);
1947                                         break;
1948                                 }
1949                                 /* FALLTHROUGH */
1950 #endif /* IPSEC */
1951
1952                         default:
1953                                 error = ENOPROTOOPT;
1954                                 break;
1955                         }
1956                         break;
1957
1958                 case SOPT_GET:
1959                         switch (optname) {
1960
1961                         case IPV6_2292PKTOPTIONS:
1962 #ifdef IPV6_PKTOPTIONS
1963                         case IPV6_PKTOPTIONS:
1964 #endif
1965                                 /*
1966                                  * RFC3542 (effectively) deprecated the
1967                                  * semantics of the 2292-style pktoptions.
1968                                  * Since it was not reliable in nature (i.e.,
1969                                  * applications had to expect the lack of some
1970                                  * information after all), it would make sense
1971                                  * to simplify this part by always returning
1972                                  * empty data.
1973                                  */
1974                                 sopt->sopt_valsize = 0;
1975                                 break;
1976
1977                         case IPV6_RECVHOPOPTS:
1978                         case IPV6_RECVDSTOPTS:
1979                         case IPV6_RECVRTHDRDSTOPTS:
1980                         case IPV6_UNICAST_HOPS:
1981                         case IPV6_RECVPKTINFO:
1982                         case IPV6_RECVHOPLIMIT:
1983                         case IPV6_RECVRTHDR:
1984                         case IPV6_RECVPATHMTU:
1985
1986                         case IPV6_V6ONLY:
1987                         case IPV6_PORTRANGE:
1988                         case IPV6_RECVTCLASS:
1989                         case IPV6_AUTOFLOWLABEL:
1990                         case IPV6_BINDANY:
1991                         case IPV6_FLOWID:
1992                         case IPV6_FLOWTYPE:
1993                         case IPV6_RECVFLOWID:
1994 #ifdef  RSS
1995                         case IPV6_RSSBUCKETID:
1996                         case IPV6_RECVRSSBUCKETID:
1997 #endif
1998                         case IPV6_BINDMULTI:
1999                                 switch (optname) {
2000
2001                                 case IPV6_RECVHOPOPTS:
2002                                         optval = OPTBIT(IN6P_HOPOPTS);
2003                                         break;
2004
2005                                 case IPV6_RECVDSTOPTS:
2006                                         optval = OPTBIT(IN6P_DSTOPTS);
2007                                         break;
2008
2009                                 case IPV6_RECVRTHDRDSTOPTS:
2010                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2011                                         break;
2012
2013                                 case IPV6_UNICAST_HOPS:
2014                                         optval = in6p->in6p_hops;
2015                                         break;
2016
2017                                 case IPV6_RECVPKTINFO:
2018                                         optval = OPTBIT(IN6P_PKTINFO);
2019                                         break;
2020
2021                                 case IPV6_RECVHOPLIMIT:
2022                                         optval = OPTBIT(IN6P_HOPLIMIT);
2023                                         break;
2024
2025                                 case IPV6_RECVRTHDR:
2026                                         optval = OPTBIT(IN6P_RTHDR);
2027                                         break;
2028
2029                                 case IPV6_RECVPATHMTU:
2030                                         optval = OPTBIT(IN6P_MTU);
2031                                         break;
2032
2033                                 case IPV6_V6ONLY:
2034                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2035                                         break;
2036
2037                                 case IPV6_PORTRANGE:
2038                                     {
2039                                         int flags;
2040                                         flags = in6p->inp_flags;
2041                                         if (flags & INP_HIGHPORT)
2042                                                 optval = IPV6_PORTRANGE_HIGH;
2043                                         else if (flags & INP_LOWPORT)
2044                                                 optval = IPV6_PORTRANGE_LOW;
2045                                         else
2046                                                 optval = 0;
2047                                         break;
2048                                     }
2049                                 case IPV6_RECVTCLASS:
2050                                         optval = OPTBIT(IN6P_TCLASS);
2051                                         break;
2052
2053                                 case IPV6_AUTOFLOWLABEL:
2054                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2055                                         break;
2056
2057                                 case IPV6_ORIGDSTADDR:
2058                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2059                                         break;
2060
2061                                 case IPV6_BINDANY:
2062                                         optval = OPTBIT(INP_BINDANY);
2063                                         break;
2064
2065                                 case IPV6_FLOWID:
2066                                         optval = in6p->inp_flowid;
2067                                         break;
2068
2069                                 case IPV6_FLOWTYPE:
2070                                         optval = in6p->inp_flowtype;
2071                                         break;
2072
2073                                 case IPV6_RECVFLOWID:
2074                                         optval = OPTBIT2(INP_RECVFLOWID);
2075                                         break;
2076 #ifdef  RSS
2077                                 case IPV6_RSSBUCKETID:
2078                                         retval =
2079                                             rss_hash2bucket(in6p->inp_flowid,
2080                                             in6p->inp_flowtype,
2081                                             &rss_bucket);
2082                                         if (retval == 0)
2083                                                 optval = rss_bucket;
2084                                         else
2085                                                 error = EINVAL;
2086                                         break;
2087
2088                                 case IPV6_RECVRSSBUCKETID:
2089                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2090                                         break;
2091 #endif
2092
2093                                 case IPV6_BINDMULTI:
2094                                         optval = OPTBIT2(INP_BINDMULTI);
2095                                         break;
2096
2097                                 }
2098                                 if (error)
2099                                         break;
2100                                 error = sooptcopyout(sopt, &optval,
2101                                         sizeof optval);
2102                                 break;
2103
2104                         case IPV6_PATHMTU:
2105                         {
2106                                 u_long pmtu = 0;
2107                                 struct ip6_mtuinfo mtuinfo;
2108                                 struct in6_addr addr;
2109
2110                                 if (!(so->so_state & SS_ISCONNECTED))
2111                                         return (ENOTCONN);
2112                                 /*
2113                                  * XXX: we dot not consider the case of source
2114                                  * routing, or optional information to specify
2115                                  * the outgoing interface.
2116                                  * Copy faddr out of in6p to avoid holding lock
2117                                  * on inp during route lookup.
2118                                  */
2119                                 INP_RLOCK(in6p);
2120                                 bcopy(&in6p->in6p_faddr, &addr, sizeof(addr));
2121                                 INP_RUNLOCK(in6p);
2122                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2123                                     &addr, &pmtu);
2124                                 if (error)
2125                                         break;
2126                                 if (pmtu > IPV6_MAXPACKET)
2127                                         pmtu = IPV6_MAXPACKET;
2128
2129                                 bzero(&mtuinfo, sizeof(mtuinfo));
2130                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2131                                 optdata = (void *)&mtuinfo;
2132                                 optdatalen = sizeof(mtuinfo);
2133                                 error = sooptcopyout(sopt, optdata,
2134                                     optdatalen);
2135                                 break;
2136                         }
2137
2138                         case IPV6_2292PKTINFO:
2139                         case IPV6_2292HOPLIMIT:
2140                         case IPV6_2292HOPOPTS:
2141                         case IPV6_2292RTHDR:
2142                         case IPV6_2292DSTOPTS:
2143                                 switch (optname) {
2144                                 case IPV6_2292PKTINFO:
2145                                         optval = OPTBIT(IN6P_PKTINFO);
2146                                         break;
2147                                 case IPV6_2292HOPLIMIT:
2148                                         optval = OPTBIT(IN6P_HOPLIMIT);
2149                                         break;
2150                                 case IPV6_2292HOPOPTS:
2151                                         optval = OPTBIT(IN6P_HOPOPTS);
2152                                         break;
2153                                 case IPV6_2292RTHDR:
2154                                         optval = OPTBIT(IN6P_RTHDR);
2155                                         break;
2156                                 case IPV6_2292DSTOPTS:
2157                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2158                                         break;
2159                                 }
2160                                 error = sooptcopyout(sopt, &optval,
2161                                     sizeof optval);
2162                                 break;
2163                         case IPV6_PKTINFO:
2164                         case IPV6_HOPOPTS:
2165                         case IPV6_RTHDR:
2166                         case IPV6_DSTOPTS:
2167                         case IPV6_RTHDRDSTOPTS:
2168                         case IPV6_NEXTHOP:
2169                         case IPV6_TCLASS:
2170                         case IPV6_DONTFRAG:
2171                         case IPV6_USE_MIN_MTU:
2172                         case IPV6_PREFER_TEMPADDR:
2173                                 error = ip6_getpcbopt(in6p, optname, sopt);
2174                                 break;
2175
2176                         case IPV6_MULTICAST_IF:
2177                         case IPV6_MULTICAST_HOPS:
2178                         case IPV6_MULTICAST_LOOP:
2179                         case IPV6_MSFILTER:
2180                                 error = ip6_getmoptions(in6p, sopt);
2181                                 break;
2182
2183 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2184                         case IPV6_IPSEC_POLICY:
2185                                 if (IPSEC_ENABLED(ipv6)) {
2186                                         error = IPSEC_PCBCTL(ipv6, in6p, sopt);
2187                                         break;
2188                                 }
2189                                 /* FALLTHROUGH */
2190 #endif /* IPSEC */
2191                         default:
2192                                 error = ENOPROTOOPT;
2193                                 break;
2194                         }
2195                         break;
2196                 }
2197         }
2198         return (error);
2199 }
2200
2201 int
2202 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2203 {
2204         int error = 0, optval, optlen;
2205         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2206         struct inpcb *in6p = sotoinpcb(so);
2207         int level, op, optname;
2208
2209         level = sopt->sopt_level;
2210         op = sopt->sopt_dir;
2211         optname = sopt->sopt_name;
2212         optlen = sopt->sopt_valsize;
2213
2214         if (level != IPPROTO_IPV6) {
2215                 return (EINVAL);
2216         }
2217
2218         switch (optname) {
2219         case IPV6_CHECKSUM:
2220                 /*
2221                  * For ICMPv6 sockets, no modification allowed for checksum
2222                  * offset, permit "no change" values to help existing apps.
2223                  *
2224                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2225                  * for an ICMPv6 socket will fail."
2226                  * The current behavior does not meet RFC3542.
2227                  */
2228                 switch (op) {
2229                 case SOPT_SET:
2230                         if (optlen != sizeof(int)) {
2231                                 error = EINVAL;
2232                                 break;
2233                         }
2234                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2235                                             sizeof(optval));
2236                         if (error)
2237                                 break;
2238                         if (optval < -1 || (optval % 2) != 0) {
2239                                 /*
2240                                  * The API assumes non-negative even offset
2241                                  * values or -1 as a special value.
2242                                  */
2243                                 error = EINVAL;
2244                         } else if (so->so_proto->pr_protocol ==
2245                             IPPROTO_ICMPV6) {
2246                                 if (optval != icmp6off)
2247                                         error = EINVAL;
2248                         } else
2249                                 in6p->in6p_cksum = optval;
2250                         break;
2251
2252                 case SOPT_GET:
2253                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2254                                 optval = icmp6off;
2255                         else
2256                                 optval = in6p->in6p_cksum;
2257
2258                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2259                         break;
2260
2261                 default:
2262                         error = EINVAL;
2263                         break;
2264                 }
2265                 break;
2266
2267         default:
2268                 error = ENOPROTOOPT;
2269                 break;
2270         }
2271
2272         return (error);
2273 }
2274
2275 /*
2276  * Set up IP6 options in pcb for insertion in output packets or
2277  * specifying behavior of outgoing packets.
2278  */
2279 static int
2280 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2281     struct socket *so, struct sockopt *sopt)
2282 {
2283         struct ip6_pktopts *opt = *pktopt;
2284         int error = 0;
2285         struct thread *td = sopt->sopt_td;
2286
2287         /* turn off any old options. */
2288         if (opt) {
2289 #ifdef DIAGNOSTIC
2290                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2291                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2292                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2293                         printf("ip6_pcbopts: all specified options are cleared.\n");
2294 #endif
2295                 ip6_clearpktopts(opt, -1);
2296         } else
2297                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2298         *pktopt = NULL;
2299
2300         if (!m || m->m_len == 0) {
2301                 /*
2302                  * Only turning off any previous options, regardless of
2303                  * whether the opt is just created or given.
2304                  */
2305                 free(opt, M_IP6OPT);
2306                 return (0);
2307         }
2308
2309         /*  set options specified by user. */
2310         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2311             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2312                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2313                 free(opt, M_IP6OPT);
2314                 return (error);
2315         }
2316         *pktopt = opt;
2317         return (0);
2318 }
2319
2320 /*
2321  * initialize ip6_pktopts.  beware that there are non-zero default values in
2322  * the struct.
2323  */
2324 void
2325 ip6_initpktopts(struct ip6_pktopts *opt)
2326 {
2327
2328         bzero(opt, sizeof(*opt));
2329         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2330         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2331         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2332         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2333 }
2334
2335 static int
2336 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2337     struct ucred *cred, int uproto)
2338 {
2339         struct ip6_pktopts *opt;
2340
2341         if (*pktopt == NULL) {
2342                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2343                     M_NOWAIT);
2344                 if (*pktopt == NULL)
2345                         return (ENOBUFS);
2346                 ip6_initpktopts(*pktopt);
2347         }
2348         opt = *pktopt;
2349
2350         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2351 }
2352
2353 #define GET_PKTOPT_VAR(field, lenexpr) do {                                     \
2354         if (pktopt && pktopt->field) {                                          \
2355                 INP_RUNLOCK(in6p);                                              \
2356                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK);         \
2357                 malloc_optdata = true;                                          \
2358                 INP_RLOCK(in6p);                                                \
2359                 if (in6p->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {           \
2360                         INP_RUNLOCK(in6p);                                      \
2361                         free(optdata, M_TEMP);                                  \
2362                         return (ECONNRESET);                                    \
2363                 }                                                               \
2364                 pktopt = in6p->in6p_outputopts;                                 \
2365                 if (pktopt && pktopt->field) {                                  \
2366                         optdatalen = min(lenexpr, sopt->sopt_valsize);          \
2367                         bcopy(&pktopt->field, optdata, optdatalen);             \
2368                 } else {                                                        \
2369                         free(optdata, M_TEMP);                                  \
2370                         optdata = NULL;                                         \
2371                         malloc_optdata = false;                                 \
2372                 }                                                               \
2373         }                                                                       \
2374 } while(0)
2375
2376 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                         \
2377         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2378
2379 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                        \
2380         pktopt->field->sa_len)
2381
2382 static int
2383 ip6_getpcbopt(struct inpcb *in6p, int optname, struct sockopt *sopt)
2384 {
2385         void *optdata = NULL;
2386         bool malloc_optdata = false;
2387         int optdatalen = 0;
2388         int error = 0;
2389         struct in6_pktinfo null_pktinfo;
2390         int deftclass = 0, on;
2391         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2392         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2393         struct ip6_pktopts *pktopt;
2394
2395         INP_RLOCK(in6p);
2396         pktopt = in6p->in6p_outputopts;
2397
2398         switch (optname) {
2399         case IPV6_PKTINFO:
2400                 optdata = (void *)&null_pktinfo;
2401                 if (pktopt && pktopt->ip6po_pktinfo) {
2402                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2403                             sizeof(null_pktinfo));
2404                         in6_clearscope(&null_pktinfo.ipi6_addr);
2405                 } else {
2406                         /* XXX: we don't have to do this every time... */
2407                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2408                 }
2409                 optdatalen = sizeof(struct in6_pktinfo);
2410                 break;
2411         case IPV6_TCLASS:
2412                 if (pktopt && pktopt->ip6po_tclass >= 0)
2413                         deftclass = pktopt->ip6po_tclass;
2414                 optdata = (void *)&deftclass;
2415                 optdatalen = sizeof(int);
2416                 break;
2417         case IPV6_HOPOPTS:
2418                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2419                 break;
2420         case IPV6_RTHDR:
2421                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2422                 break;
2423         case IPV6_RTHDRDSTOPTS:
2424                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2425                 break;
2426         case IPV6_DSTOPTS:
2427                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2428                 break;
2429         case IPV6_NEXTHOP:
2430                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2431                 break;
2432         case IPV6_USE_MIN_MTU:
2433                 if (pktopt)
2434                         defminmtu = pktopt->ip6po_minmtu;
2435                 optdata = (void *)&defminmtu;
2436                 optdatalen = sizeof(int);
2437                 break;
2438         case IPV6_DONTFRAG:
2439                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2440                         on = 1;
2441                 else
2442                         on = 0;
2443                 optdata = (void *)&on;
2444                 optdatalen = sizeof(on);
2445                 break;
2446         case IPV6_PREFER_TEMPADDR:
2447                 if (pktopt)
2448                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2449                 optdata = (void *)&defpreftemp;
2450                 optdatalen = sizeof(int);
2451                 break;
2452         default:                /* should not happen */
2453 #ifdef DIAGNOSTIC
2454                 panic("ip6_getpcbopt: unexpected option\n");
2455 #endif
2456                 INP_RUNLOCK(in6p);
2457                 return (ENOPROTOOPT);
2458         }
2459         INP_RUNLOCK(in6p);
2460
2461         error = sooptcopyout(sopt, optdata, optdatalen);
2462         if (malloc_optdata)
2463                 free(optdata, M_TEMP);
2464
2465         return (error);
2466 }
2467
2468 void
2469 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2470 {
2471         if (pktopt == NULL)
2472                 return;
2473
2474         if (optname == -1 || optname == IPV6_PKTINFO) {
2475                 if (pktopt->ip6po_pktinfo)
2476                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2477                 pktopt->ip6po_pktinfo = NULL;
2478         }
2479         if (optname == -1 || optname == IPV6_HOPLIMIT)
2480                 pktopt->ip6po_hlim = -1;
2481         if (optname == -1 || optname == IPV6_TCLASS)
2482                 pktopt->ip6po_tclass = -1;
2483         if (optname == -1 || optname == IPV6_NEXTHOP) {
2484                 if (pktopt->ip6po_nextroute.ro_rt) {
2485                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2486                         pktopt->ip6po_nextroute.ro_rt = NULL;
2487                 }
2488                 if (pktopt->ip6po_nexthop)
2489                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2490                 pktopt->ip6po_nexthop = NULL;
2491         }
2492         if (optname == -1 || optname == IPV6_HOPOPTS) {
2493                 if (pktopt->ip6po_hbh)
2494                         free(pktopt->ip6po_hbh, M_IP6OPT);
2495                 pktopt->ip6po_hbh = NULL;
2496         }
2497         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2498                 if (pktopt->ip6po_dest1)
2499                         free(pktopt->ip6po_dest1, M_IP6OPT);
2500                 pktopt->ip6po_dest1 = NULL;
2501         }
2502         if (optname == -1 || optname == IPV6_RTHDR) {
2503                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2504                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2505                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2506                 if (pktopt->ip6po_route.ro_rt) {
2507                         RTFREE(pktopt->ip6po_route.ro_rt);
2508                         pktopt->ip6po_route.ro_rt = NULL;
2509                 }
2510         }
2511         if (optname == -1 || optname == IPV6_DSTOPTS) {
2512                 if (pktopt->ip6po_dest2)
2513                         free(pktopt->ip6po_dest2, M_IP6OPT);
2514                 pktopt->ip6po_dest2 = NULL;
2515         }
2516 }
2517
2518 #define PKTOPT_EXTHDRCPY(type) \
2519 do {\
2520         if (src->type) {\
2521                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2522                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2523                 if (dst->type == NULL)\
2524                         goto bad;\
2525                 bcopy(src->type, dst->type, hlen);\
2526         }\
2527 } while (/*CONSTCOND*/ 0)
2528
2529 static int
2530 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2531 {
2532         if (dst == NULL || src == NULL)  {
2533                 printf("ip6_clearpktopts: invalid argument\n");
2534                 return (EINVAL);
2535         }
2536
2537         dst->ip6po_hlim = src->ip6po_hlim;
2538         dst->ip6po_tclass = src->ip6po_tclass;
2539         dst->ip6po_flags = src->ip6po_flags;
2540         dst->ip6po_minmtu = src->ip6po_minmtu;
2541         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2542         if (src->ip6po_pktinfo) {
2543                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2544                     M_IP6OPT, canwait);
2545                 if (dst->ip6po_pktinfo == NULL)
2546                         goto bad;
2547                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2548         }
2549         if (src->ip6po_nexthop) {
2550                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2551                     M_IP6OPT, canwait);
2552                 if (dst->ip6po_nexthop == NULL)
2553                         goto bad;
2554                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2555                     src->ip6po_nexthop->sa_len);
2556         }
2557         PKTOPT_EXTHDRCPY(ip6po_hbh);
2558         PKTOPT_EXTHDRCPY(ip6po_dest1);
2559         PKTOPT_EXTHDRCPY(ip6po_dest2);
2560         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2561         return (0);
2562
2563   bad:
2564         ip6_clearpktopts(dst, -1);
2565         return (ENOBUFS);
2566 }
2567 #undef PKTOPT_EXTHDRCPY
2568
2569 struct ip6_pktopts *
2570 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2571 {
2572         int error;
2573         struct ip6_pktopts *dst;
2574
2575         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2576         if (dst == NULL)
2577                 return (NULL);
2578         ip6_initpktopts(dst);
2579
2580         if ((error = copypktopts(dst, src, canwait)) != 0) {
2581                 free(dst, M_IP6OPT);
2582                 return (NULL);
2583         }
2584
2585         return (dst);
2586 }
2587
2588 void
2589 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2590 {
2591         if (pktopt == NULL)
2592                 return;
2593
2594         ip6_clearpktopts(pktopt, -1);
2595
2596         free(pktopt, M_IP6OPT);
2597 }
2598
2599 /*
2600  * Set IPv6 outgoing packet options based on advanced API.
2601  */
2602 int
2603 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2604     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2605 {
2606         struct cmsghdr *cm = NULL;
2607
2608         if (control == NULL || opt == NULL)
2609                 return (EINVAL);
2610
2611         ip6_initpktopts(opt);
2612         if (stickyopt) {
2613                 int error;
2614
2615                 /*
2616                  * If stickyopt is provided, make a local copy of the options
2617                  * for this particular packet, then override them by ancillary
2618                  * objects.
2619                  * XXX: copypktopts() does not copy the cached route to a next
2620                  * hop (if any).  This is not very good in terms of efficiency,
2621                  * but we can allow this since this option should be rarely
2622                  * used.
2623                  */
2624                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2625                         return (error);
2626         }
2627
2628         /*
2629          * XXX: Currently, we assume all the optional information is stored
2630          * in a single mbuf.
2631          */
2632         if (control->m_next)
2633                 return (EINVAL);
2634
2635         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2636             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2637                 int error;
2638
2639                 if (control->m_len < CMSG_LEN(0))
2640                         return (EINVAL);
2641
2642                 cm = mtod(control, struct cmsghdr *);
2643                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2644                         return (EINVAL);
2645                 if (cm->cmsg_level != IPPROTO_IPV6)
2646                         continue;
2647
2648                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2649                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2650                 if (error)
2651                         return (error);
2652         }
2653
2654         return (0);
2655 }
2656
2657 /*
2658  * Set a particular packet option, as a sticky option or an ancillary data
2659  * item.  "len" can be 0 only when it's a sticky option.
2660  * We have 4 cases of combination of "sticky" and "cmsg":
2661  * "sticky=0, cmsg=0": impossible
2662  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2663  * "sticky=1, cmsg=0": RFC3542 socket option
2664  * "sticky=1, cmsg=1": RFC2292 socket option
2665  */
2666 static int
2667 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2668     struct ucred *cred, int sticky, int cmsg, int uproto)
2669 {
2670         int minmtupolicy, preftemp;
2671         int error;
2672
2673         if (!sticky && !cmsg) {
2674 #ifdef DIAGNOSTIC
2675                 printf("ip6_setpktopt: impossible case\n");
2676 #endif
2677                 return (EINVAL);
2678         }
2679
2680         /*
2681          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2682          * not be specified in the context of RFC3542.  Conversely,
2683          * RFC3542 types should not be specified in the context of RFC2292.
2684          */
2685         if (!cmsg) {
2686                 switch (optname) {
2687                 case IPV6_2292PKTINFO:
2688                 case IPV6_2292HOPLIMIT:
2689                 case IPV6_2292NEXTHOP:
2690                 case IPV6_2292HOPOPTS:
2691                 case IPV6_2292DSTOPTS:
2692                 case IPV6_2292RTHDR:
2693                 case IPV6_2292PKTOPTIONS:
2694                         return (ENOPROTOOPT);
2695                 }
2696         }
2697         if (sticky && cmsg) {
2698                 switch (optname) {
2699                 case IPV6_PKTINFO:
2700                 case IPV6_HOPLIMIT:
2701                 case IPV6_NEXTHOP:
2702                 case IPV6_HOPOPTS:
2703                 case IPV6_DSTOPTS:
2704                 case IPV6_RTHDRDSTOPTS:
2705                 case IPV6_RTHDR:
2706                 case IPV6_USE_MIN_MTU:
2707                 case IPV6_DONTFRAG:
2708                 case IPV6_TCLASS:
2709                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2710                         return (ENOPROTOOPT);
2711                 }
2712         }
2713
2714         switch (optname) {
2715         case IPV6_2292PKTINFO:
2716         case IPV6_PKTINFO:
2717         {
2718                 struct ifnet *ifp = NULL;
2719                 struct in6_pktinfo *pktinfo;
2720
2721                 if (len != sizeof(struct in6_pktinfo))
2722                         return (EINVAL);
2723
2724                 pktinfo = (struct in6_pktinfo *)buf;
2725
2726                 /*
2727                  * An application can clear any sticky IPV6_PKTINFO option by
2728                  * doing a "regular" setsockopt with ipi6_addr being
2729                  * in6addr_any and ipi6_ifindex being zero.
2730                  * [RFC 3542, Section 6]
2731                  */
2732                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2733                     pktinfo->ipi6_ifindex == 0 &&
2734                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2735                         ip6_clearpktopts(opt, optname);
2736                         break;
2737                 }
2738
2739                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2740                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2741                         return (EINVAL);
2742                 }
2743                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2744                         return (EINVAL);
2745                 /* validate the interface index if specified. */
2746                 if (pktinfo->ipi6_ifindex > V_if_index)
2747                          return (ENXIO);
2748                 if (pktinfo->ipi6_ifindex) {
2749                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2750                         if (ifp == NULL)
2751                                 return (ENXIO);
2752                 }
2753                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2754                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2755                         return (ENETDOWN);
2756
2757                 if (ifp != NULL &&
2758                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2759                         struct in6_ifaddr *ia;
2760
2761                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2762                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2763                         if (ia == NULL)
2764                                 return (EADDRNOTAVAIL);
2765                         ifa_free(&ia->ia_ifa);
2766                 }
2767                 /*
2768                  * We store the address anyway, and let in6_selectsrc()
2769                  * validate the specified address.  This is because ipi6_addr
2770                  * may not have enough information about its scope zone, and
2771                  * we may need additional information (such as outgoing
2772                  * interface or the scope zone of a destination address) to
2773                  * disambiguate the scope.
2774                  * XXX: the delay of the validation may confuse the
2775                  * application when it is used as a sticky option.
2776                  */
2777                 if (opt->ip6po_pktinfo == NULL) {
2778                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2779                             M_IP6OPT, M_NOWAIT);
2780                         if (opt->ip6po_pktinfo == NULL)
2781                                 return (ENOBUFS);
2782                 }
2783                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2784                 break;
2785         }
2786
2787         case IPV6_2292HOPLIMIT:
2788         case IPV6_HOPLIMIT:
2789         {
2790                 int *hlimp;
2791
2792                 /*
2793                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2794                  * to simplify the ordering among hoplimit options.
2795                  */
2796                 if (optname == IPV6_HOPLIMIT && sticky)
2797                         return (ENOPROTOOPT);
2798
2799                 if (len != sizeof(int))
2800                         return (EINVAL);
2801                 hlimp = (int *)buf;
2802                 if (*hlimp < -1 || *hlimp > 255)
2803                         return (EINVAL);
2804
2805                 opt->ip6po_hlim = *hlimp;
2806                 break;
2807         }
2808
2809         case IPV6_TCLASS:
2810         {
2811                 int tclass;
2812
2813                 if (len != sizeof(int))
2814                         return (EINVAL);
2815                 tclass = *(int *)buf;
2816                 if (tclass < -1 || tclass > 255)
2817                         return (EINVAL);
2818
2819                 opt->ip6po_tclass = tclass;
2820                 break;
2821         }
2822
2823         case IPV6_2292NEXTHOP:
2824         case IPV6_NEXTHOP:
2825                 if (cred != NULL) {
2826                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2827                         if (error)
2828                                 return (error);
2829                 }
2830
2831                 if (len == 0) { /* just remove the option */
2832                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
2833                         break;
2834                 }
2835
2836                 /* check if cmsg_len is large enough for sa_len */
2837                 if (len < sizeof(struct sockaddr) || len < *buf)
2838                         return (EINVAL);
2839
2840                 switch (((struct sockaddr *)buf)->sa_family) {
2841                 case AF_INET6:
2842                 {
2843                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2844                         int error;
2845
2846                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2847                                 return (EINVAL);
2848
2849                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2850                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2851                                 return (EINVAL);
2852                         }
2853                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2854                             != 0) {
2855                                 return (error);
2856                         }
2857                         break;
2858                 }
2859                 case AF_LINK:   /* should eventually be supported */
2860                 default:
2861                         return (EAFNOSUPPORT);
2862                 }
2863
2864                 /* turn off the previous option, then set the new option. */
2865                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2866                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2867                 if (opt->ip6po_nexthop == NULL)
2868                         return (ENOBUFS);
2869                 bcopy(buf, opt->ip6po_nexthop, *buf);
2870                 break;
2871
2872         case IPV6_2292HOPOPTS:
2873         case IPV6_HOPOPTS:
2874         {
2875                 struct ip6_hbh *hbh;
2876                 int hbhlen;
2877
2878                 /*
2879                  * XXX: We don't allow a non-privileged user to set ANY HbH
2880                  * options, since per-option restriction has too much
2881                  * overhead.
2882                  */
2883                 if (cred != NULL) {
2884                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2885                         if (error)
2886                                 return (error);
2887                 }
2888
2889                 if (len == 0) {
2890                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
2891                         break;  /* just remove the option */
2892                 }
2893
2894                 /* message length validation */
2895                 if (len < sizeof(struct ip6_hbh))
2896                         return (EINVAL);
2897                 hbh = (struct ip6_hbh *)buf;
2898                 hbhlen = (hbh->ip6h_len + 1) << 3;
2899                 if (len != hbhlen)
2900                         return (EINVAL);
2901
2902                 /* turn off the previous option, then set the new option. */
2903                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2904                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2905                 if (opt->ip6po_hbh == NULL)
2906                         return (ENOBUFS);
2907                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2908
2909                 break;
2910         }
2911
2912         case IPV6_2292DSTOPTS:
2913         case IPV6_DSTOPTS:
2914         case IPV6_RTHDRDSTOPTS:
2915         {
2916                 struct ip6_dest *dest, **newdest = NULL;
2917                 int destlen;
2918
2919                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
2920                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
2921                         if (error)
2922                                 return (error);
2923                 }
2924
2925                 if (len == 0) {
2926                         ip6_clearpktopts(opt, optname);
2927                         break;  /* just remove the option */
2928                 }
2929
2930                 /* message length validation */
2931                 if (len < sizeof(struct ip6_dest))
2932                         return (EINVAL);
2933                 dest = (struct ip6_dest *)buf;
2934                 destlen = (dest->ip6d_len + 1) << 3;
2935                 if (len != destlen)
2936                         return (EINVAL);
2937
2938                 /*
2939                  * Determine the position that the destination options header
2940                  * should be inserted; before or after the routing header.
2941                  */
2942                 switch (optname) {
2943                 case IPV6_2292DSTOPTS:
2944                         /*
2945                          * The old advacned API is ambiguous on this point.
2946                          * Our approach is to determine the position based
2947                          * according to the existence of a routing header.
2948                          * Note, however, that this depends on the order of the
2949                          * extension headers in the ancillary data; the 1st
2950                          * part of the destination options header must appear
2951                          * before the routing header in the ancillary data,
2952                          * too.
2953                          * RFC3542 solved the ambiguity by introducing
2954                          * separate ancillary data or option types.
2955                          */
2956                         if (opt->ip6po_rthdr == NULL)
2957                                 newdest = &opt->ip6po_dest1;
2958                         else
2959                                 newdest = &opt->ip6po_dest2;
2960                         break;
2961                 case IPV6_RTHDRDSTOPTS:
2962                         newdest = &opt->ip6po_dest1;
2963                         break;
2964                 case IPV6_DSTOPTS:
2965                         newdest = &opt->ip6po_dest2;
2966                         break;
2967                 }
2968
2969                 /* turn off the previous option, then set the new option. */
2970                 ip6_clearpktopts(opt, optname);
2971                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
2972                 if (*newdest == NULL)
2973                         return (ENOBUFS);
2974                 bcopy(dest, *newdest, destlen);
2975
2976                 break;
2977         }
2978
2979         case IPV6_2292RTHDR:
2980         case IPV6_RTHDR:
2981         {
2982                 struct ip6_rthdr *rth;
2983                 int rthlen;
2984
2985                 if (len == 0) {
2986                         ip6_clearpktopts(opt, IPV6_RTHDR);
2987                         break;  /* just remove the option */
2988                 }
2989
2990                 /* message length validation */
2991                 if (len < sizeof(struct ip6_rthdr))
2992                         return (EINVAL);
2993                 rth = (struct ip6_rthdr *)buf;
2994                 rthlen = (rth->ip6r_len + 1) << 3;
2995                 if (len != rthlen)
2996                         return (EINVAL);
2997
2998                 switch (rth->ip6r_type) {
2999                 case IPV6_RTHDR_TYPE_0:
3000                         if (rth->ip6r_len == 0) /* must contain one addr */
3001                                 return (EINVAL);
3002                         if (rth->ip6r_len % 2) /* length must be even */
3003                                 return (EINVAL);
3004                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3005                                 return (EINVAL);
3006                         break;
3007                 default:
3008                         return (EINVAL);        /* not supported */
3009                 }
3010
3011                 /* turn off the previous option */
3012                 ip6_clearpktopts(opt, IPV6_RTHDR);
3013                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3014                 if (opt->ip6po_rthdr == NULL)
3015                         return (ENOBUFS);
3016                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3017
3018                 break;
3019         }
3020
3021         case IPV6_USE_MIN_MTU:
3022                 if (len != sizeof(int))
3023                         return (EINVAL);
3024                 minmtupolicy = *(int *)buf;
3025                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3026                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3027                     minmtupolicy != IP6PO_MINMTU_ALL) {
3028                         return (EINVAL);
3029                 }
3030                 opt->ip6po_minmtu = minmtupolicy;
3031                 break;
3032
3033         case IPV6_DONTFRAG:
3034                 if (len != sizeof(int))
3035                         return (EINVAL);
3036
3037                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3038                         /*
3039                          * we ignore this option for TCP sockets.
3040                          * (RFC3542 leaves this case unspecified.)
3041                          */
3042                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3043                 } else
3044                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3045                 break;
3046
3047         case IPV6_PREFER_TEMPADDR:
3048                 if (len != sizeof(int))
3049                         return (EINVAL);
3050                 preftemp = *(int *)buf;
3051                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3052                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3053                     preftemp != IP6PO_TEMPADDR_PREFER) {
3054                         return (EINVAL);
3055                 }
3056                 opt->ip6po_prefer_tempaddr = preftemp;
3057                 break;
3058
3059         default:
3060                 return (ENOPROTOOPT);
3061         } /* end of switch */
3062
3063         return (0);
3064 }
3065
3066 /*
3067  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3068  * packet to the input queue of a specified interface.  Note that this
3069  * calls the output routine of the loopback "driver", but with an interface
3070  * pointer that might NOT be &loif -- easier than replicating that code here.
3071  */
3072 void
3073 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3074 {
3075         struct mbuf *copym;
3076         struct ip6_hdr *ip6;
3077
3078         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3079         if (copym == NULL)
3080                 return;
3081
3082         /*
3083          * Make sure to deep-copy IPv6 header portion in case the data
3084          * is in an mbuf cluster, so that we can safely override the IPv6
3085          * header portion later.
3086          */
3087         if (!M_WRITABLE(copym) ||
3088             copym->m_len < sizeof(struct ip6_hdr)) {
3089                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3090                 if (copym == NULL)
3091                         return;
3092         }
3093         ip6 = mtod(copym, struct ip6_hdr *);
3094         /*
3095          * clear embedded scope identifiers if necessary.
3096          * in6_clearscope will touch the addresses only when necessary.
3097          */
3098         in6_clearscope(&ip6->ip6_src);
3099         in6_clearscope(&ip6->ip6_dst);
3100         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3101                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3102                     CSUM_PSEUDO_HDR;
3103                 copym->m_pkthdr.csum_data = 0xffff;
3104         }
3105         if_simloop(ifp, copym, AF_INET6, 0);
3106 }
3107
3108 /*
3109  * Chop IPv6 header off from the payload.
3110  */
3111 static int
3112 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3113 {
3114         struct mbuf *mh;
3115         struct ip6_hdr *ip6;
3116
3117         ip6 = mtod(m, struct ip6_hdr *);
3118         if (m->m_len > sizeof(*ip6)) {
3119                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3120                 if (mh == NULL) {
3121                         m_freem(m);
3122                         return ENOBUFS;
3123                 }
3124                 m_move_pkthdr(mh, m);
3125                 M_ALIGN(mh, sizeof(*ip6));
3126                 m->m_len -= sizeof(*ip6);
3127                 m->m_data += sizeof(*ip6);
3128                 mh->m_next = m;
3129                 m = mh;
3130                 m->m_len = sizeof(*ip6);
3131                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3132         }
3133         exthdrs->ip6e_ip6 = m;
3134         return 0;
3135 }
3136
3137 /*
3138  * Compute IPv6 extension header length.
3139  */
3140 int
3141 ip6_optlen(struct inpcb *in6p)
3142 {
3143         int len;
3144
3145         if (!in6p->in6p_outputopts)
3146                 return 0;
3147
3148         len = 0;
3149 #define elen(x) \
3150     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3151
3152         len += elen(in6p->in6p_outputopts->ip6po_hbh);
3153         if (in6p->in6p_outputopts->ip6po_rthdr)
3154                 /* dest1 is valid with rthdr only */
3155                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
3156         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
3157         len += elen(in6p->in6p_outputopts->ip6po_dest2);
3158         return len;
3159 #undef elen
3160 }