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