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 ip6_pktopts *, 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(u_short) > m->m_len) {
 203                 printf("%s: delayed m_pullup, m->len: %d plen %u off %u "
 204                     "csum_flags=%b\n", __func__, m->m_len, plen, offset,
 205                     (int)m->m_pkthdr.csum_flags, CSUM_BITS);
 206                 /*
 207                  * XXX this should not happen, but if it does, the correct
 208                  * behavior may be to insert the checksum in the appropriate
 209                  * next mbuf in the chain.
 210                  */
 211                 return;
 212         }
 213         *(u_short *)(m->m_data + offset) = csum;
 214 }
 215
 216 int
 217 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 218     int fraglen , uint32_t id)
 219 {
 220         struct mbuf *m, **mnext, *m_frgpart;
 221         struct ip6_hdr *ip6, *mhip6;
 222         struct ip6_frag *ip6f;
 223         int off;
 224         int error;
 225         int tlen = m0->m_pkthdr.len;
 226
 227         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 228
 229         m = m0;
 230         ip6 = mtod(m, struct ip6_hdr *);
 231         mnext = &m->m_nextpkt;
 232
 233         for (off = hlen; off < tlen; off += fraglen) {
 234                 m = m_gethdr(M_NOWAIT, MT_DATA);
 235                 if (!m) {
 236                         IP6STAT_INC(ip6s_odropped);
 237                         return (ENOBUFS);
 238                 }
 239                 m->m_flags = m0->m_flags & M_COPYFLAGS;
 240                 *mnext = m;
 241                 mnext = &m->m_nextpkt;
 242                 m->m_data += max_linkhdr;
 243                 mhip6 = mtod(m, struct ip6_hdr *);
 244                 *mhip6 = *ip6;
 245                 m->m_len = sizeof(*mhip6);
 246                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 247                 if (error) {
 248                         IP6STAT_INC(ip6s_odropped);
 249                         return (error);
 250                 }
 251                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 252                 if (off + fraglen >= tlen)
 253                         fraglen = tlen - off;
 254                 else
 255                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 256                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 257                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 258                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 259                         IP6STAT_INC(ip6s_odropped);
 260                         return (ENOBUFS);
 261                 }
 262                 m_cat(m, m_frgpart);
 263                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 264                 m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum;
 265                 m->m_pkthdr.rcvif = NULL;
 266                 ip6f->ip6f_reserved = 0;
 267                 ip6f->ip6f_ident = id;
 268                 ip6f->ip6f_nxt = nextproto;
 269                 IP6STAT_INC(ip6s_ofragments);
 270                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 271         }
 272
 273         return (0);
 274 }
 275
 276 /*
 277  * IP6 output. The packet in mbuf chain m contains a skeletal IP6
 278  * header (with pri, len, nxt, hlim, src, dst).
 279  * This function may modify ver and hlim only.
 280  * The mbuf chain containing the packet will be freed.
 281  * The mbuf opt, if present, will not be freed.
 282  * If route_in6 ro is present and has ro_rt initialized, route lookup would be
 283  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 284  * then result of route lookup is stored in ro->ro_rt.
 285  *
 286  * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
 287  * nd_ifinfo.linkmtu is u_int32_t.  so we use u_long to hold largest one,
 288  * which is rt_mtu.
 289  *
 290  * ifpp - XXX: just for statistics
 291  */
 292 /*
 293  * XXX TODO: no flowid is assigned for outbound flows?
 294  */
 295 int
 296 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 297     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 298     struct ifnet **ifpp, struct inpcb *inp)
 299 {
 300         struct ip6_hdr *ip6;
 301         struct ifnet *ifp, *origifp;
 302         struct mbuf *m = m0;
 303         struct mbuf *mprev = NULL;
 304         int hlen, tlen, len;
 305         struct route_in6 ip6route;
 306         struct rtentry *rt = NULL;
 307         struct sockaddr_in6 *dst, src_sa, dst_sa;
 308         struct in6_addr odst;
 309         int error = 0;
 310         struct in6_ifaddr *ia = NULL;
 311         u_long mtu;
 312         int alwaysfrag, dontfrag;
 313         u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
 314         struct ip6_exthdrs exthdrs;
 315         struct in6_addr src0, dst0;
 316         u_int32_t zone;
 317         struct route_in6 *ro_pmtu = NULL;
 318         int hdrsplit = 0;
 319         int sw_csum, tso;
 320         int needfiblookup;
 321         uint32_t fibnum;
 322         struct m_tag *fwd_tag = NULL;
 323         uint32_t id;
 324
 325         if (inp != NULL) {
 326                 INP_LOCK_ASSERT(inp);
 327                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 328                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 329                         /* unconditionally set flowid */
 330                         m->m_pkthdr.flowid = inp->inp_flowid;
 331                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 332                 }
 333         }
 334
 335 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 336         /*
 337          * IPSec checking which handles several cases.
 338          * FAST IPSEC: We re-injected the packet.
 339          * XXX: need scope argument.
 340          */
 341         if (IPSEC_ENABLED(ipv6)) {
 342                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 343                         if (error == EINPROGRESS)
 344                                 error = 0;
 345                         goto done;
 346                 }
 347         }
 348 #endif /* IPSEC */
 349
 350         bzero(&exthdrs, sizeof(exthdrs));
 351         if (opt) {
 352                 /* Hop-by-Hop options header */
 353                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
 354                 /* Destination options header(1st part) */
 355                 if (opt->ip6po_rthdr) {
 356                         /*
 357                          * Destination options header(1st part)
 358                          * This only makes sense with a routing header.
 359                          * See Section 9.2 of RFC 3542.
 360                          * Disabling this part just for MIP6 convenience is
 361                          * a bad idea.  We need to think carefully about a
 362                          * way to make the advanced API coexist with MIP6
 363                          * options, which might automatically be inserted in
 364                          * the kernel.
 365                          */
 366                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
 367                 }
 368                 /* Routing header */
 369                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
 370                 /* Destination options header(2nd part) */
 371                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
 372         }
 373
 374         /*
 375          * Calculate the total length of the extension header chain.
 376          * Keep the length of the unfragmentable part for fragmentation.
 377          */
 378         optlen = 0;
 379         if (exthdrs.ip6e_hbh)
 380                 optlen += exthdrs.ip6e_hbh->m_len;
 381         if (exthdrs.ip6e_dest1)
 382                 optlen += exthdrs.ip6e_dest1->m_len;
 383         if (exthdrs.ip6e_rthdr)
 384                 optlen += exthdrs.ip6e_rthdr->m_len;
 385         unfragpartlen = optlen + sizeof(struct ip6_hdr);
 386
 387         /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */
 388         if (exthdrs.ip6e_dest2)
 389                 optlen += exthdrs.ip6e_dest2->m_len;
 390
 391         /*
 392          * If there is at least one extension header,
 393          * separate IP6 header from the payload.
 394          */
 395         if (optlen && !hdrsplit) {
 396                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 397                         m = NULL;
 398                         goto freehdrs;
 399                 }
 400                 m = exthdrs.ip6e_ip6;
 401                 hdrsplit++;
 402         }
 403
 404         ip6 = mtod(m, struct ip6_hdr *);
 405
 406         /* adjust mbuf packet header length */
 407         m->m_pkthdr.len += optlen;
 408         plen = m->m_pkthdr.len - sizeof(*ip6);
 409
 410         /* If this is a jumbo payload, insert a jumbo payload option. */
 411         if (plen > IPV6_MAXPACKET) {
 412                 if (!hdrsplit) {
 413                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 414                                 m = NULL;
 415                                 goto freehdrs;
 416                         }
 417                         m = exthdrs.ip6e_ip6;
 418                         hdrsplit++;
 419                 }
 420                 /* adjust pointer */
 421                 ip6 = mtod(m, struct ip6_hdr *);
 422                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 423                         goto freehdrs;
 424                 ip6->ip6_plen = 0;
 425         } else
 426                 ip6->ip6_plen = htons(plen);
 427
 428         /*
 429          * Concatenate headers and fill in next header fields.
 430          * Here we have, on "m"
 431          *      IPv6 payload
 432          * and we insert headers accordingly.  Finally, we should be getting:
 433          *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
 434          *
 435          * during the header composing process, "m" points to IPv6 header.
 436          * "mprev" points to an extension header prior to esp.
 437          */
 438         u_char *nexthdrp = &ip6->ip6_nxt;
 439         mprev = m;
 440
 441         /*
 442          * we treat dest2 specially.  this makes IPsec processing
 443          * much easier.  the goal here is to make mprev point the
 444          * mbuf prior to dest2.
 445          *
 446          * result: IPv6 dest2 payload
 447          * m and mprev will point to IPv6 header.
 448          */
 449         if (exthdrs.ip6e_dest2) {
 450                 if (!hdrsplit)
 451                         panic("assumption failed: hdr not split");
 452                 exthdrs.ip6e_dest2->m_next = m->m_next;
 453                 m->m_next = exthdrs.ip6e_dest2;
 454                 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 455                 ip6->ip6_nxt = IPPROTO_DSTOPTS;
 456         }
 457
 458         /*
 459          * result: IPv6 hbh dest1 rthdr dest2 payload
 460          * m will point to IPv6 header.  mprev will point to the
 461          * extension header prior to dest2 (rthdr in the above case).
 462          */
 463         MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 464         MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 465                    IPPROTO_DSTOPTS);
 466         MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 467                    IPPROTO_ROUTING);
 468
 469         /*
 470          * If there is a routing header, discard the packet.
 471          */
 472         if (exthdrs.ip6e_rthdr) {
 473                  error = EINVAL;
 474                  goto bad;
 475         }
 476
 477         /* Source address validation */
 478         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 479             (flags & IPV6_UNSPECSRC) == 0) {
 480                 error = EOPNOTSUPP;
 481                 IP6STAT_INC(ip6s_badscope);
 482                 goto bad;
 483         }
 484         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 485                 error = EOPNOTSUPP;
 486                 IP6STAT_INC(ip6s_badscope);
 487                 goto bad;
 488         }
 489
 490         IP6STAT_INC(ip6s_localout);
 491
 492         /*
 493          * Route packet.
 494          */
 495         if (ro == NULL) {
 496                 ro = &ip6route;
 497                 bzero((caddr_t)ro, sizeof(*ro));
 498         }
 499         ro_pmtu = ro;
 500         if (opt && opt->ip6po_rthdr)
 501                 ro = &opt->ip6po_route;
 502         dst = (struct sockaddr_in6 *)&ro->ro_dst;
 503         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 504 again:
 505         /*
 506          * if specified, try to fill in the traffic class field.
 507          * do not override if a non-zero value is already set.
 508          * we check the diffserv field and the ecn field separately.
 509          */
 510         if (opt && opt->ip6po_tclass >= 0) {
 511                 int mask = 0;
 512
 513                 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
 514                         mask |= 0xfc;
 515                 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
 516                         mask |= 0x03;
 517                 if (mask != 0)
 518                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 519         }
 520
 521         /* fill in or override the hop limit field, if necessary. */
 522         if (opt && opt->ip6po_hlim != -1)
 523                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 524         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 525                 if (im6o != NULL)
 526                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 527                 else
 528                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 529         }
 530         /*
 531          * Validate route against routing table additions;
 532          * a better/more specific route might have been added.
 533          * Make sure address family is set in route.
 534          */
 535         if (inp) {
 536                 ro->ro_dst.sin6_family = AF_INET6;
 537                 RT_VALIDATE((struct route *)ro, &inp->inp_rt_cookie, fibnum);
 538         }
 539         if (ro->ro_rt && fwd_tag == NULL && (ro->ro_rt->rt_flags & RTF_UP) &&
 540             ro->ro_dst.sin6_family == AF_INET6 &&
 541             IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 542                 rt = ro->ro_rt;
 543                 ifp = ro->ro_rt->rt_ifp;
 544         } else {
 545                 if (ro->ro_lle)
 546                         LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 547                 ro->ro_lle = NULL;
 548                 if (fwd_tag == NULL) {
 549                         bzero(&dst_sa, sizeof(dst_sa));
 550                         dst_sa.sin6_family = AF_INET6;
 551                         dst_sa.sin6_len = sizeof(dst_sa);
 552                         dst_sa.sin6_addr = ip6->ip6_dst;
 553                 }
 554                 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
 555                     &rt, fibnum);
 556                 if (error != 0) {
 557                         if (ifp != NULL)
 558                                 in6_ifstat_inc(ifp, ifs6_out_discard);
 559                         goto bad;
 560                 }
 561         }
 562         if (rt == NULL) {
 563                 /*
 564                  * If in6_selectroute() does not return a route entry,
 565                  * dst may not have been updated.
 566                  */
 567                 *dst = dst_sa;  /* XXX */
 568         }
 569
 570         /*
 571          * then rt (for unicast) and ifp must be non-NULL valid values.
 572          */
 573         if ((flags & IPV6_FORWARDING) == 0) {
 574                 /* XXX: the FORWARDING flag can be set for mrouting. */
 575                 in6_ifstat_inc(ifp, ifs6_out_request);
 576         }
 577         if (rt != NULL) {
 578                 ia = (struct in6_ifaddr *)(rt->rt_ifa);
 579                 counter_u64_add(rt->rt_pksent, 1);
 580         }
 581
 582
 583         /*
 584          * The outgoing interface must be in the zone of source and
 585          * destination addresses.
 586          */
 587         origifp = ifp;
 588
 589         src0 = ip6->ip6_src;
 590         if (in6_setscope(&src0, origifp, &zone))
 591                 goto badscope;
 592         bzero(&src_sa, sizeof(src_sa));
 593         src_sa.sin6_family = AF_INET6;
 594         src_sa.sin6_len = sizeof(src_sa);
 595         src_sa.sin6_addr = ip6->ip6_src;
 596         if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id)
 597                 goto badscope;
 598
 599         dst0 = ip6->ip6_dst;
 600         if (in6_setscope(&dst0, origifp, &zone))
 601                 goto badscope;
 602         /* re-initialize to be sure */
 603         bzero(&dst_sa, sizeof(dst_sa));
 604         dst_sa.sin6_family = AF_INET6;
 605         dst_sa.sin6_len = sizeof(dst_sa);
 606         dst_sa.sin6_addr = ip6->ip6_dst;
 607         if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) {
 608                 goto badscope;
 609         }
 610
 611         /* We should use ia_ifp to support the case of
 612          * sending packets to an address of our own.
 613          */
 614         if (ia != NULL && ia->ia_ifp)
 615                 ifp = ia->ia_ifp;
 616
 617         /* scope check is done. */
 618         goto routefound;
 619
 620   badscope:
 621         IP6STAT_INC(ip6s_badscope);
 622         in6_ifstat_inc(origifp, ifs6_out_discard);
 623         if (error == 0)
 624                 error = EHOSTUNREACH; /* XXX */
 625         goto bad;
 626
 627   routefound:
 628         if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 629                 if (opt && opt->ip6po_nextroute.ro_rt) {
 630                         /*
 631                          * The nexthop is explicitly specified by the
 632                          * application.  We assume the next hop is an IPv6
 633                          * address.
 634                          */
 635                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 636                 }
 637                 else if ((rt->rt_flags & RTF_GATEWAY))
 638                         dst = (struct sockaddr_in6 *)rt->rt_gateway;
 639         }
 640
 641         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 642                 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
 643         } else {
 644                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 645                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 646                 /*
 647                  * Confirm that the outgoing interface supports multicast.
 648                  */
 649                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 650                         IP6STAT_INC(ip6s_noroute);
 651                         in6_ifstat_inc(ifp, ifs6_out_discard);
 652                         error = ENETUNREACH;
 653                         goto bad;
 654                 }
 655                 if ((im6o == NULL && in6_mcast_loop) ||
 656                     (im6o && im6o->im6o_multicast_loop)) {
 657                         /*
 658                          * Loop back multicast datagram if not expressly
 659                          * forbidden to do so, even if we have not joined
 660                          * the address; protocols will filter it later,
 661                          * thus deferring a hash lookup and lock acquisition
 662                          * at the expense of an m_copym().
 663                          */
 664                         ip6_mloopback(ifp, m);
 665                 } else {
 666                         /*
 667                          * If we are acting as a multicast router, perform
 668                          * multicast forwarding as if the packet had just
 669                          * arrived on the interface to which we are about
 670                          * to send.  The multicast forwarding function
 671                          * recursively calls this function, using the
 672                          * IPV6_FORWARDING flag to prevent infinite recursion.
 673                          *
 674                          * Multicasts that are looped back by ip6_mloopback(),
 675                          * above, will be forwarded by the ip6_input() routine,
 676                          * if necessary.
 677                          */
 678                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 679                                 /*
 680                                  * XXX: ip6_mforward expects that rcvif is NULL
 681                                  * when it is called from the originating path.
 682                                  * However, it may not always be the case.
 683                                  */
 684                                 m->m_pkthdr.rcvif = NULL;
 685                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 686                                         m_freem(m);
 687                                         goto done;
 688                                 }
 689                         }
 690                 }
 691                 /*
 692                  * Multicasts with a hoplimit of zero may be looped back,
 693                  * above, but must not be transmitted on a network.
 694                  * Also, multicasts addressed to the loopback interface
 695                  * are not sent -- the above call to ip6_mloopback() will
 696                  * loop back a copy if this host actually belongs to the
 697                  * destination group on the loopback interface.
 698                  */
 699                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 700                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 701                         m_freem(m);
 702                         goto done;
 703                 }
 704         }
 705
 706         /*
 707          * Fill the outgoing inteface to tell the upper layer
 708          * to increment per-interface statistics.
 709          */
 710         if (ifpp)
 711                 *ifpp = ifp;
 712
 713         /* Determine path MTU. */
 714         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 715                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 716                 goto bad;
 717
 718         /*
 719          * The caller of this function may specify to use the minimum MTU
 720          * in some cases.
 721          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 722          * setting.  The logic is a bit complicated; by default, unicast
 723          * packets will follow path MTU while multicast packets will be sent at
 724          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 725          * including unicast ones will be sent at the minimum MTU.  Multicast
 726          * packets will always be sent at the minimum MTU unless
 727          * IP6PO_MINMTU_DISABLE is explicitly specified.
 728          * See RFC 3542 for more details.
 729          */
 730         if (mtu > IPV6_MMTU) {
 731                 if ((flags & IPV6_MINMTU))
 732                         mtu = IPV6_MMTU;
 733                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 734                         mtu = IPV6_MMTU;
 735                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 736                          (opt == NULL ||
 737                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 738                         mtu = IPV6_MMTU;
 739                 }
 740         }
 741
 742         /*
 743          * clear embedded scope identifiers if necessary.
 744          * in6_clearscope will touch the addresses only when necessary.
 745          */
 746         in6_clearscope(&ip6->ip6_src);
 747         in6_clearscope(&ip6->ip6_dst);
 748
 749         /*
 750          * If the outgoing packet contains a hop-by-hop options header,
 751          * it must be examined and processed even by the source node.
 752          * (RFC 2460, section 4.)
 753          */
 754         if (exthdrs.ip6e_hbh) {
 755                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 756                 u_int32_t dummy; /* XXX unused */
 757                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 758
 759 #ifdef DIAGNOSTIC
 760                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 761                         panic("ip6e_hbh is not contiguous");
 762 #endif
 763                 /*
 764                  *  XXX: if we have to send an ICMPv6 error to the sender,
 765                  *       we need the M_LOOP flag since icmp6_error() expects
 766                  *       the IPv6 and the hop-by-hop options header are
 767                  *       contiguous unless the flag is set.
 768                  */
 769                 m->m_flags |= M_LOOP;
 770                 m->m_pkthdr.rcvif = ifp;
 771                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
 772                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
 773                     &dummy, &plen) < 0) {
 774                         /* m was already freed at this point */
 775                         error = EINVAL;/* better error? */
 776                         goto done;
 777                 }
 778                 m->m_flags &= ~M_LOOP; /* XXX */
 779                 m->m_pkthdr.rcvif = NULL;
 780         }
 781
 782         /* Jump over all PFIL processing if hooks are not active. */
 783         if (!PFIL_HOOKED(&V_inet6_pfil_hook))
 784                 goto passout;
 785
 786         odst = ip6->ip6_dst;
 787         /* Run through list of hooks for output packets. */
 788         error = pfil_run_hooks(&V_inet6_pfil_hook, &m, ifp, PFIL_OUT, inp);
 789         if (error != 0 || m == NULL)
 790                 goto done;
 791         /* adjust pointer */
 792         ip6 = mtod(m, struct ip6_hdr *);
 793
 794         needfiblookup = 0;
 795         /* See if destination IP address was changed by packet filter. */
 796         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
 797                 m->m_flags |= M_SKIP_FIREWALL;
 798                 /* If destination is now ourself drop to ip6_input(). */
 799                 if (in6_localip(&ip6->ip6_dst)) {
 800                         m->m_flags |= M_FASTFWD_OURS;
 801                         if (m->m_pkthdr.rcvif == NULL)
 802                                 m->m_pkthdr.rcvif = V_loif;
 803                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 804                                 m->m_pkthdr.csum_flags |=
 805                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 806                                 m->m_pkthdr.csum_data = 0xffff;
 807                         }
 808 #ifdef SCTP
 809                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 810                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 811 #endif
 812                         error = netisr_queue(NETISR_IPV6, m);
 813                         goto done;
 814                 } else {
 815                         RO_RTFREE(ro);
 816                         needfiblookup = 1; /* Redo the routing table lookup. */
 817                         if (ro->ro_lle)
 818                                 LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 819                         ro->ro_lle = NULL;
 820                 }
 821         }
 822         /* See if fib was changed by packet filter. */
 823         if (fibnum != M_GETFIB(m)) {
 824                 m->m_flags |= M_SKIP_FIREWALL;
 825                 fibnum = M_GETFIB(m);
 826                 RO_RTFREE(ro);
 827                 needfiblookup = 1;
 828                 if (ro->ro_lle)
 829                         LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 830                 ro->ro_lle = NULL;
 831         }
 832         if (needfiblookup)
 833                 goto again;
 834
 835         /* See if local, if yes, send it to netisr. */
 836         if (m->m_flags & M_FASTFWD_OURS) {
 837                 if (m->m_pkthdr.rcvif == NULL)
 838                         m->m_pkthdr.rcvif = V_loif;
 839                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
 840                         m->m_pkthdr.csum_flags |=
 841                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
 842                         m->m_pkthdr.csum_data = 0xffff;
 843                 }
 844 #ifdef SCTP
 845                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
 846                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 847 #endif
 848                 error = netisr_queue(NETISR_IPV6, m);
 849                 goto done;
 850         }
 851         /* Or forward to some other address? */
 852         if ((m->m_flags & M_IP6_NEXTHOP) &&
 853             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 854                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 855                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
 856                 m->m_flags |= M_SKIP_FIREWALL;
 857                 m->m_flags &= ~M_IP6_NEXTHOP;
 858                 m_tag_delete(m, fwd_tag);
 859                 goto again;
 860         }
 861
 862 passout:
 863         /*
 864          * Send the packet to the outgoing interface.
 865          * If necessary, do IPv6 fragmentation before sending.
 866          *
 867          * the logic here is rather complex:
 868          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
 869          * 1-a: send as is if tlen <= path mtu
 870          * 1-b: fragment if tlen > path mtu
 871          *
 872          * 2: if user asks us not to fragment (dontfrag == 1)
 873          * 2-a: send as is if tlen <= interface mtu
 874          * 2-b: error if tlen > interface mtu
 875          *
 876          * 3: if we always need to attach fragment header (alwaysfrag == 1)
 877          *      always fragment
 878          *
 879          * 4: if dontfrag == 1 && alwaysfrag == 1
 880          *      error, as we cannot handle this conflicting request
 881          */
 882         sw_csum = m->m_pkthdr.csum_flags;
 883         if (!hdrsplit) {
 884                 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
 885                 sw_csum &= ~ifp->if_hwassist;
 886         } else
 887                 tso = 0;
 888         /*
 889          * If we added extension headers, we will not do TSO and calculate the
 890          * checksums ourselves for now.
 891          * XXX-BZ  Need a framework to know when the NIC can handle it, even
 892          * with ext. hdrs.
 893          */
 894         if (sw_csum & CSUM_DELAY_DATA_IPV6) {
 895                 sw_csum &= ~CSUM_DELAY_DATA_IPV6;
 896                 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
 897         }
 898 #ifdef SCTP
 899         if (sw_csum & CSUM_SCTP_IPV6) {
 900                 sw_csum &= ~CSUM_SCTP_IPV6;
 901                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
 902         }
 903 #endif
 904         m->m_pkthdr.csum_flags &= ifp->if_hwassist;
 905         tlen = m->m_pkthdr.len;
 906
 907         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
 908                 dontfrag = 1;
 909         else
 910                 dontfrag = 0;
 911         if (dontfrag && alwaysfrag) {   /* case 4 */
 912                 /* conflicting request - can't transmit */
 913                 error = EMSGSIZE;
 914                 goto bad;
 915         }
 916         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* case 2-b */
 917                 /*
 918                  * Even if the DONTFRAG option is specified, we cannot send the
 919                  * packet when the data length is larger than the MTU of the
 920                  * outgoing interface.
 921                  * Notify the error by sending IPV6_PATHMTU ancillary data if
 922                  * application wanted to know the MTU value. Also return an
 923                  * error code (this is not described in the API spec).
 924                  */
 925                 if (inp != NULL)
 926                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
 927                 error = EMSGSIZE;
 928                 goto bad;
 929         }
 930
 931         /*
 932          * transmit packet without fragmentation
 933          */
 934         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
 935                 struct in6_ifaddr *ia6;
 936
 937                 ip6 = mtod(m, struct ip6_hdr *);
 938                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
 939                 if (ia6) {
 940                         /* Record statistics for this interface address. */
 941                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
 942                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
 943                             m->m_pkthdr.len);
 944                         ifa_free(&ia6->ia_ifa);
 945                 }
 946 #ifdef RATELIMIT
 947                 if (inp != NULL) {
 948                         if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 949                                 in_pcboutput_txrtlmt(inp, ifp, m);
 950                         /* stamp send tag on mbuf */
 951                         m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 952                 } else {
 953                         m->m_pkthdr.snd_tag = NULL;
 954                 }
 955 #endif
 956                 error = nd6_output_ifp(ifp, origifp, m, dst,
 957                     (struct route *)ro);
 958 #ifdef RATELIMIT
 959                 /* check for route change */
 960                 if (error == EAGAIN)
 961                         in_pcboutput_eagain(inp);
 962 #endif
 963                 goto done;
 964         }
 965
 966         /*
 967          * try to fragment the packet.  case 1-b and 3
 968          */
 969         if (mtu < IPV6_MMTU) {
 970                 /* path MTU cannot be less than IPV6_MMTU */
 971                 error = EMSGSIZE;
 972                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 973                 goto bad;
 974         } else if (ip6->ip6_plen == 0) {
 975                 /* jumbo payload cannot be fragmented */
 976                 error = EMSGSIZE;
 977                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
 978                 goto bad;
 979         } else {
 980                 u_char nextproto;
 981
 982                 /*
 983                  * Too large for the destination or interface;
 984                  * fragment if possible.
 985                  * Must be able to put at least 8 bytes per fragment.
 986                  */
 987                 hlen = unfragpartlen;
 988                 if (mtu > IPV6_MAXPACKET)
 989                         mtu = IPV6_MAXPACKET;
 990
 991                 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
 992                 if (len < 8) {
 993                         error = EMSGSIZE;
 994                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
 995                         goto bad;
 996                 }
 997
 998                 /*
 999                  * If the interface will not calculate checksums on
1000                  * fragmented packets, then do it here.
1001                  * XXX-BZ handle the hw offloading case.  Need flags.
1002                  */
1003                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1004                         in6_delayed_cksum(m, plen, hlen);
1005                         m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
1006                 }
1007 #ifdef SCTP
1008                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
1009                         sctp_delayed_cksum(m, hlen);
1010                         m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
1011                 }
1012 #endif
1013                 /*
1014                  * Change the next header field of the last header in the
1015                  * unfragmentable part.
1016                  */
1017                 if (exthdrs.ip6e_rthdr) {
1018                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1019                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1020                 } else if (exthdrs.ip6e_dest1) {
1021                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1022                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1023                 } else if (exthdrs.ip6e_hbh) {
1024                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1025                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1026                 } else {
1027                         nextproto = ip6->ip6_nxt;
1028                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1029                 }
1030
1031                 /*
1032                  * Loop through length of segment after first fragment,
1033                  * make new header and copy data of each part and link onto
1034                  * chain.
1035                  */
1036                 m0 = m;
1037                 id = htonl(ip6_randomid());
1038                 if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
1039                         goto sendorfree;
1040
1041                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1042         }
1043
1044         /*
1045          * Remove leading garbages.
1046          */
1047 sendorfree:
1048         m = m0->m_nextpkt;
1049         m0->m_nextpkt = 0;
1050         m_freem(m0);
1051         for (m0 = m; m; m = m0) {
1052                 m0 = m->m_nextpkt;
1053                 m->m_nextpkt = 0;
1054                 if (error == 0) {
1055                         /* Record statistics for this interface address. */
1056                         if (ia) {
1057                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1058                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1059                                     m->m_pkthdr.len);
1060                         }
1061 #ifdef RATELIMIT
1062                         if (inp != NULL) {
1063                                 if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
1064                                         in_pcboutput_txrtlmt(inp, ifp, m);
1065                                 /* stamp send tag on mbuf */
1066                                 m->m_pkthdr.snd_tag = inp->inp_snd_tag;
1067                         } else {
1068                                 m->m_pkthdr.snd_tag = NULL;
1069                         }
1070 #endif
1071                         error = nd6_output_ifp(ifp, origifp, m, dst,
1072                             (struct route *)ro);
1073 #ifdef RATELIMIT
1074                         /* check for route change */
1075                         if (error == EAGAIN)
1076                                 in_pcboutput_eagain(inp);
1077 #endif
1078                 } else
1079                         m_freem(m);
1080         }
1081
1082         if (error == 0)
1083                 IP6STAT_INC(ip6s_fragmented);
1084
1085 done:
1086         if (ro == &ip6route)
1087                 RO_RTFREE(ro);
1088         return (error);
1089
1090 freehdrs:
1091         m_freem(exthdrs.ip6e_hbh);      /* m_freem will check if mbuf is 0 */
1092         m_freem(exthdrs.ip6e_dest1);
1093         m_freem(exthdrs.ip6e_rthdr);
1094         m_freem(exthdrs.ip6e_dest2);
1095         /* FALLTHROUGH */
1096 bad:
1097         if (m)
1098                 m_freem(m);
1099         goto done;
1100 }
1101
1102 static int
1103 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1104 {
1105         struct mbuf *m;
1106
1107         if (hlen > MCLBYTES)
1108                 return (ENOBUFS); /* XXX */
1109
1110         if (hlen > MLEN)
1111                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1112         else
1113                 m = m_get(M_NOWAIT, MT_DATA);
1114         if (m == NULL)
1115                 return (ENOBUFS);
1116         m->m_len = hlen;
1117         if (hdr)
1118                 bcopy(hdr, mtod(m, caddr_t), hlen);
1119
1120         *mp = m;
1121         return (0);
1122 }
1123
1124 /*
1125  * Insert jumbo payload option.
1126  */
1127 static int
1128 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1129 {
1130         struct mbuf *mopt;
1131         u_char *optbuf;
1132         u_int32_t v;
1133
1134 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1135
1136         /*
1137          * If there is no hop-by-hop options header, allocate new one.
1138          * If there is one but it doesn't have enough space to store the
1139          * jumbo payload option, allocate a cluster to store the whole options.
1140          * Otherwise, use it to store the options.
1141          */
1142         if (exthdrs->ip6e_hbh == NULL) {
1143                 mopt = m_get(M_NOWAIT, MT_DATA);
1144                 if (mopt == NULL)
1145                         return (ENOBUFS);
1146                 mopt->m_len = JUMBOOPTLEN;
1147                 optbuf = mtod(mopt, u_char *);
1148                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1149                 exthdrs->ip6e_hbh = mopt;
1150         } else {
1151                 struct ip6_hbh *hbh;
1152
1153                 mopt = exthdrs->ip6e_hbh;
1154                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1155                         /*
1156                          * XXX assumption:
1157                          * - exthdrs->ip6e_hbh is not referenced from places
1158                          *   other than exthdrs.
1159                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1160                          */
1161                         int oldoptlen = mopt->m_len;
1162                         struct mbuf *n;
1163
1164                         /*
1165                          * XXX: give up if the whole (new) hbh header does
1166                          * not fit even in an mbuf cluster.
1167                          */
1168                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1169                                 return (ENOBUFS);
1170
1171                         /*
1172                          * As a consequence, we must always prepare a cluster
1173                          * at this point.
1174                          */
1175                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1176                         if (n == NULL)
1177                                 return (ENOBUFS);
1178                         n->m_len = oldoptlen + JUMBOOPTLEN;
1179                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1180                             oldoptlen);
1181                         optbuf = mtod(n, caddr_t) + oldoptlen;
1182                         m_freem(mopt);
1183                         mopt = exthdrs->ip6e_hbh = n;
1184                 } else {
1185                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1186                         mopt->m_len += JUMBOOPTLEN;
1187                 }
1188                 optbuf[0] = IP6OPT_PADN;
1189                 optbuf[1] = 1;
1190
1191                 /*
1192                  * Adjust the header length according to the pad and
1193                  * the jumbo payload option.
1194                  */
1195                 hbh = mtod(mopt, struct ip6_hbh *);
1196                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1197         }
1198
1199         /* fill in the option. */
1200         optbuf[2] = IP6OPT_JUMBO;
1201         optbuf[3] = 4;
1202         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1203         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1204
1205         /* finally, adjust the packet header length */
1206         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1207
1208         return (0);
1209 #undef JUMBOOPTLEN
1210 }
1211
1212 /*
1213  * Insert fragment header and copy unfragmentable header portions.
1214  */
1215 static int
1216 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1217     struct ip6_frag **frghdrp)
1218 {
1219         struct mbuf *n, *mlast;
1220
1221         if (hlen > sizeof(struct ip6_hdr)) {
1222                 n = m_copym(m0, sizeof(struct ip6_hdr),
1223                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1224                 if (n == NULL)
1225                         return (ENOBUFS);
1226                 m->m_next = n;
1227         } else
1228                 n = m;
1229
1230         /* Search for the last mbuf of unfragmentable part. */
1231         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1232                 ;
1233
1234         if (M_WRITABLE(mlast) &&
1235             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1236                 /* use the trailing space of the last mbuf for the fragment hdr */
1237                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1238                     mlast->m_len);
1239                 mlast->m_len += sizeof(struct ip6_frag);
1240                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1241         } else {
1242                 /* allocate a new mbuf for the fragment header */
1243                 struct mbuf *mfrg;
1244
1245                 mfrg = m_get(M_NOWAIT, MT_DATA);
1246                 if (mfrg == NULL)
1247                         return (ENOBUFS);
1248                 mfrg->m_len = sizeof(struct ip6_frag);
1249                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1250                 mlast->m_next = mfrg;
1251         }
1252
1253         return (0);
1254 }
1255
1256 /*
1257  * Calculates IPv6 path mtu for destination @dst.
1258  * Resulting MTU is stored in @mtup.
1259  *
1260  * Returns 0 on success.
1261  */
1262 static int
1263 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1264 {
1265         struct nhop6_extended nh6;
1266         struct in6_addr kdst;
1267         uint32_t scopeid;
1268         struct ifnet *ifp;
1269         u_long mtu;
1270         int error;
1271
1272         in6_splitscope(dst, &kdst, &scopeid);
1273         if (fib6_lookup_nh_ext(fibnum, &kdst, scopeid, NHR_REF, 0, &nh6) != 0)
1274                 return (EHOSTUNREACH);
1275
1276         ifp = nh6.nh_ifp;
1277         mtu = nh6.nh_mtu;
1278
1279         error = ip6_calcmtu(ifp, dst, mtu, mtup, NULL, 0);
1280         fib6_free_nh_ext(fibnum, &nh6);
1281
1282         return (error);
1283 }
1284
1285 /*
1286  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1287  * and cached data in @ro_pmtu.
1288  * MTU from (successful) route lookup is saved (along with dst)
1289  * inside @ro_pmtu to avoid subsequent route lookups after packet
1290  * filter processing.
1291  *
1292  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1293  * Returns 0 on success.
1294  */
1295 static int
1296 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1297     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1298     int *alwaysfragp, u_int fibnum, u_int proto)
1299 {
1300         struct nhop6_basic nh6;
1301         struct in6_addr kdst;
1302         uint32_t scopeid;
1303         struct sockaddr_in6 *sa6_dst;
1304         u_long mtu;
1305
1306         mtu = 0;
1307         if (do_lookup) {
1308
1309                 /*
1310                  * Here ro_pmtu has final destination address, while
1311                  * ro might represent immediate destination.
1312                  * Use ro_pmtu destination since mtu might differ.
1313                  */
1314                 sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1315                 if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1316                         ro_pmtu->ro_mtu = 0;
1317
1318                 if (ro_pmtu->ro_mtu == 0) {
1319                         bzero(sa6_dst, sizeof(*sa6_dst));
1320                         sa6_dst->sin6_family = AF_INET6;
1321                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1322                         sa6_dst->sin6_addr = *dst;
1323
1324                         in6_splitscope(dst, &kdst, &scopeid);
1325                         if (fib6_lookup_nh_basic(fibnum, &kdst, scopeid, 0, 0,
1326                             &nh6) == 0)
1327                                 ro_pmtu->ro_mtu = nh6.nh_mtu;
1328                 }
1329
1330                 mtu = ro_pmtu->ro_mtu;
1331         }
1332
1333         if (ro_pmtu->ro_rt)
1334                 mtu = ro_pmtu->ro_rt->rt_mtu;
1335
1336         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1337 }
1338
1339 /*
1340  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1341  * hostcache data for @dst.
1342  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1343  *
1344  * Returns 0 on success.
1345  */
1346 static int
1347 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1348     u_long *mtup, int *alwaysfragp, u_int proto)
1349 {
1350         u_long mtu = 0;
1351         int alwaysfrag = 0;
1352         int error = 0;
1353
1354         if (rt_mtu > 0) {
1355                 u_int32_t ifmtu;
1356                 struct in_conninfo inc;
1357
1358                 bzero(&inc, sizeof(inc));
1359                 inc.inc_flags |= INC_ISIPV6;
1360                 inc.inc6_faddr = *dst;
1361
1362                 ifmtu = IN6_LINKMTU(ifp);
1363
1364                 /* TCP is known to react to pmtu changes so skip hc */
1365                 if (proto != IPPROTO_TCP)
1366                         mtu = tcp_hc_getmtu(&inc);
1367
1368                 if (mtu)
1369                         mtu = min(mtu, rt_mtu);
1370                 else
1371                         mtu = rt_mtu;
1372                 if (mtu == 0)
1373                         mtu = ifmtu;
1374                 else if (mtu < IPV6_MMTU) {
1375                         /*
1376                          * RFC2460 section 5, last paragraph:
1377                          * if we record ICMPv6 too big message with
1378                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1379                          * or smaller, with framgent header attached.
1380                          * (fragment header is needed regardless from the
1381                          * packet size, for translators to identify packets)
1382                          */
1383                         alwaysfrag = 1;
1384                         mtu = IPV6_MMTU;
1385                 }
1386         } else if (ifp) {
1387                 mtu = IN6_LINKMTU(ifp);
1388         } else
1389                 error = EHOSTUNREACH; /* XXX */
1390
1391         *mtup = mtu;
1392         if (alwaysfragp)
1393                 *alwaysfragp = alwaysfrag;
1394         return (error);
1395 }
1396
1397 /*
1398  * IP6 socket option processing.
1399  */
1400 int
1401 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1402 {
1403         int optdatalen, uproto;
1404         void *optdata;
1405         struct inpcb *in6p = sotoinpcb(so);
1406         int error, optval;
1407         int level, op, optname;
1408         int optlen;
1409         struct thread *td;
1410 #ifdef  RSS
1411         uint32_t rss_bucket;
1412         int retval;
1413 #endif
1414
1415 /*
1416  * Don't use more than a quarter of mbuf clusters.  N.B.:
1417  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1418  * on LP64 architectures, so cast to u_long to avoid undefined
1419  * behavior.  ILP32 architectures cannot have nmbclusters
1420  * large enough to overflow for other reasons.
1421  */
1422 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1423
1424         level = sopt->sopt_level;
1425         op = sopt->sopt_dir;
1426         optname = sopt->sopt_name;
1427         optlen = sopt->sopt_valsize;
1428         td = sopt->sopt_td;
1429         error = 0;
1430         optval = 0;
1431         uproto = (int)so->so_proto->pr_protocol;
1432
1433         if (level != IPPROTO_IPV6) {
1434                 error = EINVAL;
1435
1436                 if (sopt->sopt_level == SOL_SOCKET &&
1437                     sopt->sopt_dir == SOPT_SET) {
1438                         switch (sopt->sopt_name) {
1439                         case SO_REUSEADDR:
1440                                 INP_WLOCK(in6p);
1441                                 if ((so->so_options & SO_REUSEADDR) != 0)
1442                                         in6p->inp_flags2 |= INP_REUSEADDR;
1443                                 else
1444                                         in6p->inp_flags2 &= ~INP_REUSEADDR;
1445                                 INP_WUNLOCK(in6p);
1446                                 error = 0;
1447                                 break;
1448                         case SO_REUSEPORT:
1449                                 INP_WLOCK(in6p);
1450                                 if ((so->so_options & SO_REUSEPORT) != 0)
1451                                         in6p->inp_flags2 |= INP_REUSEPORT;
1452                                 else
1453                                         in6p->inp_flags2 &= ~INP_REUSEPORT;
1454                                 INP_WUNLOCK(in6p);
1455                                 error = 0;
1456                                 break;
1457                         case SO_SETFIB:
1458                                 INP_WLOCK(in6p);
1459                                 in6p->inp_inc.inc_fibnum = so->so_fibnum;
1460                                 INP_WUNLOCK(in6p);
1461                                 error = 0;
1462                                 break;
1463                         case SO_MAX_PACING_RATE:
1464 #ifdef RATELIMIT
1465                                 INP_WLOCK(in6p);
1466                                 in6p->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1467                                 INP_WUNLOCK(in6p);
1468                                 error = 0;
1469 #else
1470                                 error = EOPNOTSUPP;
1471 #endif
1472                                 break;
1473                         default:
1474                                 break;
1475                         }
1476                 }
1477         } else {                /* level == IPPROTO_IPV6 */
1478                 switch (op) {
1479
1480                 case SOPT_SET:
1481                         switch (optname) {
1482                         case IPV6_2292PKTOPTIONS:
1483 #ifdef IPV6_PKTOPTIONS
1484                         case IPV6_PKTOPTIONS:
1485 #endif
1486                         {
1487                                 struct mbuf *m;
1488
1489                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1490                                         printf("ip6_ctloutput: mbuf limit hit\n");
1491                                         error = ENOBUFS;
1492                                         break;
1493                                 }
1494
1495                                 error = soopt_getm(sopt, &m); /* XXX */
1496                                 if (error != 0)
1497                                         break;
1498                                 error = soopt_mcopyin(sopt, m); /* XXX */
1499                                 if (error != 0)
1500                                         break;
1501                                 error = ip6_pcbopts(&in6p->in6p_outputopts,
1502                                                     m, so, sopt);
1503                                 m_freem(m); /* XXX */
1504                                 break;
1505                         }
1506
1507                         /*
1508                          * Use of some Hop-by-Hop options or some
1509                          * Destination options, might require special
1510                          * privilege.  That is, normal applications
1511                          * (without special privilege) might be forbidden
1512                          * from setting certain options in outgoing packets,
1513                          * and might never see certain options in received
1514                          * packets. [RFC 2292 Section 6]
1515                          * KAME specific note:
1516                          *  KAME prevents non-privileged users from sending or
1517                          *  receiving ANY hbh/dst options in order to avoid
1518                          *  overhead of parsing options in the kernel.
1519                          */
1520                         case IPV6_RECVHOPOPTS:
1521                         case IPV6_RECVDSTOPTS:
1522                         case IPV6_RECVRTHDRDSTOPTS:
1523                                 if (td != NULL) {
1524                                         error = priv_check(td,
1525                                             PRIV_NETINET_SETHDROPTS);
1526                                         if (error)
1527                                                 break;
1528                                 }
1529                                 /* FALLTHROUGH */
1530                         case IPV6_UNICAST_HOPS:
1531                         case IPV6_HOPLIMIT:
1532
1533                         case IPV6_RECVPKTINFO:
1534                         case IPV6_RECVHOPLIMIT:
1535                         case IPV6_RECVRTHDR:
1536                         case IPV6_RECVPATHMTU:
1537                         case IPV6_RECVTCLASS:
1538                         case IPV6_RECVFLOWID:
1539 #ifdef  RSS
1540                         case IPV6_RECVRSSBUCKETID:
1541 #endif
1542                         case IPV6_V6ONLY:
1543                         case IPV6_AUTOFLOWLABEL:
1544                         case IPV6_ORIGDSTADDR:
1545                         case IPV6_BINDANY:
1546                         case IPV6_BINDMULTI:
1547 #ifdef  RSS
1548                         case IPV6_RSS_LISTEN_BUCKET:
1549 #endif
1550                                 if (optname == IPV6_BINDANY && td != NULL) {
1551                                         error = priv_check(td,
1552                                             PRIV_NETINET_BINDANY);
1553                                         if (error)
1554                                                 break;
1555                                 }
1556
1557                                 if (optlen != sizeof(int)) {
1558                                         error = EINVAL;
1559                                         break;
1560                                 }
1561                                 error = sooptcopyin(sopt, &optval,
1562                                         sizeof optval, sizeof optval);
1563                                 if (error)
1564                                         break;
1565                                 switch (optname) {
1566
1567                                 case IPV6_UNICAST_HOPS:
1568                                         if (optval < -1 || optval >= 256)
1569                                                 error = EINVAL;
1570                                         else {
1571                                                 /* -1 = kernel default */
1572                                                 in6p->in6p_hops = optval;
1573                                                 if ((in6p->inp_vflag &
1574                                                      INP_IPV4) != 0)
1575                                                         in6p->inp_ip_ttl = optval;
1576                                         }
1577                                         break;
1578 #define OPTSET(bit) \
1579 do { \
1580         INP_WLOCK(in6p); \
1581         if (optval) \
1582                 in6p->inp_flags |= (bit); \
1583         else \
1584                 in6p->inp_flags &= ~(bit); \
1585         INP_WUNLOCK(in6p); \
1586 } while (/*CONSTCOND*/ 0)
1587 #define OPTSET2292(bit) \
1588 do { \
1589         INP_WLOCK(in6p); \
1590         in6p->inp_flags |= IN6P_RFC2292; \
1591         if (optval) \
1592                 in6p->inp_flags |= (bit); \
1593         else \
1594                 in6p->inp_flags &= ~(bit); \
1595         INP_WUNLOCK(in6p); \
1596 } while (/*CONSTCOND*/ 0)
1597 #define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0)
1598
1599 #define OPTSET2(bit, val) do {                                          \
1600         INP_WLOCK(in6p);                                                \
1601         if (val)                                                        \
1602                 in6p->inp_flags2 |= bit;                                \
1603         else                                                            \
1604                 in6p->inp_flags2 &= ~bit;                               \
1605         INP_WUNLOCK(in6p);                                              \
1606 } while (0)
1607 #define OPTBIT2(bit) (in6p->inp_flags2 & (bit) ? 1 : 0)
1608
1609                                 case IPV6_RECVPKTINFO:
1610                                         /* cannot mix with RFC2292 */
1611                                         if (OPTBIT(IN6P_RFC2292)) {
1612                                                 error = EINVAL;
1613                                                 break;
1614                                         }
1615                                         OPTSET(IN6P_PKTINFO);
1616                                         break;
1617
1618                                 case IPV6_HOPLIMIT:
1619                                 {
1620                                         struct ip6_pktopts **optp;
1621
1622                                         /* cannot mix with RFC2292 */
1623                                         if (OPTBIT(IN6P_RFC2292)) {
1624                                                 error = EINVAL;
1625                                                 break;
1626                                         }
1627                                         optp = &in6p->in6p_outputopts;
1628                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1629                                             (u_char *)&optval, sizeof(optval),
1630                                             optp, (td != NULL) ? td->td_ucred :
1631                                             NULL, uproto);
1632                                         break;
1633                                 }
1634
1635                                 case IPV6_RECVHOPLIMIT:
1636                                         /* cannot mix with RFC2292 */
1637                                         if (OPTBIT(IN6P_RFC2292)) {
1638                                                 error = EINVAL;
1639                                                 break;
1640                                         }
1641                                         OPTSET(IN6P_HOPLIMIT);
1642                                         break;
1643
1644                                 case IPV6_RECVHOPOPTS:
1645                                         /* cannot mix with RFC2292 */
1646                                         if (OPTBIT(IN6P_RFC2292)) {
1647                                                 error = EINVAL;
1648                                                 break;
1649                                         }
1650                                         OPTSET(IN6P_HOPOPTS);
1651                                         break;
1652
1653                                 case IPV6_RECVDSTOPTS:
1654                                         /* cannot mix with RFC2292 */
1655                                         if (OPTBIT(IN6P_RFC2292)) {
1656                                                 error = EINVAL;
1657                                                 break;
1658                                         }
1659                                         OPTSET(IN6P_DSTOPTS);
1660                                         break;
1661
1662                                 case IPV6_RECVRTHDRDSTOPTS:
1663                                         /* cannot mix with RFC2292 */
1664                                         if (OPTBIT(IN6P_RFC2292)) {
1665                                                 error = EINVAL;
1666                                                 break;
1667                                         }
1668                                         OPTSET(IN6P_RTHDRDSTOPTS);
1669                                         break;
1670
1671                                 case IPV6_RECVRTHDR:
1672                                         /* cannot mix with RFC2292 */
1673                                         if (OPTBIT(IN6P_RFC2292)) {
1674                                                 error = EINVAL;
1675                                                 break;
1676                                         }
1677                                         OPTSET(IN6P_RTHDR);
1678                                         break;
1679
1680                                 case IPV6_RECVPATHMTU:
1681                                         /*
1682                                          * We ignore this option for TCP
1683                                          * sockets.
1684                                          * (RFC3542 leaves this case
1685                                          * unspecified.)
1686                                          */
1687                                         if (uproto != IPPROTO_TCP)
1688                                                 OPTSET(IN6P_MTU);
1689                                         break;
1690
1691                                 case IPV6_RECVFLOWID:
1692                                         OPTSET2(INP_RECVFLOWID, optval);
1693                                         break;
1694
1695 #ifdef  RSS
1696                                 case IPV6_RECVRSSBUCKETID:
1697                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1698                                         break;
1699 #endif
1700
1701                                 case IPV6_V6ONLY:
1702                                         /*
1703                                          * make setsockopt(IPV6_V6ONLY)
1704                                          * available only prior to bind(2).
1705                                          * see ipng mailing list, Jun 22 2001.
1706                                          */
1707                                         if (in6p->inp_lport ||
1708                                             !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
1709                                                 error = EINVAL;
1710                                                 break;
1711                                         }
1712                                         OPTSET(IN6P_IPV6_V6ONLY);
1713                                         if (optval)
1714                                                 in6p->inp_vflag &= ~INP_IPV4;
1715                                         else
1716                                                 in6p->inp_vflag |= INP_IPV4;
1717                                         break;
1718                                 case IPV6_RECVTCLASS:
1719                                         /* cannot mix with RFC2292 XXX */
1720                                         if (OPTBIT(IN6P_RFC2292)) {
1721                                                 error = EINVAL;
1722                                                 break;
1723                                         }
1724                                         OPTSET(IN6P_TCLASS);
1725                                         break;
1726                                 case IPV6_AUTOFLOWLABEL:
1727                                         OPTSET(IN6P_AUTOFLOWLABEL);
1728                                         break;
1729
1730                                 case IPV6_ORIGDSTADDR:
1731                                         OPTSET2(INP_ORIGDSTADDR, optval);
1732                                         break;
1733                                 case IPV6_BINDANY:
1734                                         OPTSET(INP_BINDANY);
1735                                         break;
1736
1737                                 case IPV6_BINDMULTI:
1738                                         OPTSET2(INP_BINDMULTI, optval);
1739                                         break;
1740 #ifdef  RSS
1741                                 case IPV6_RSS_LISTEN_BUCKET:
1742                                         if ((optval >= 0) &&
1743                                             (optval < rss_getnumbuckets())) {
1744                                                 in6p->inp_rss_listen_bucket = optval;
1745                                                 OPTSET2(INP_RSS_BUCKET_SET, 1);
1746                                         } else {
1747                                                 error = EINVAL;
1748                                         }
1749                                         break;
1750 #endif
1751                                 }
1752                                 break;
1753
1754                         case IPV6_TCLASS:
1755                         case IPV6_DONTFRAG:
1756                         case IPV6_USE_MIN_MTU:
1757                         case IPV6_PREFER_TEMPADDR:
1758                                 if (optlen != sizeof(optval)) {
1759                                         error = EINVAL;
1760                                         break;
1761                                 }
1762                                 error = sooptcopyin(sopt, &optval,
1763                                         sizeof optval, sizeof optval);
1764                                 if (error)
1765                                         break;
1766                                 {
1767                                         struct ip6_pktopts **optp;
1768                                         optp = &in6p->in6p_outputopts;
1769                                         error = ip6_pcbopt(optname,
1770                                             (u_char *)&optval, sizeof(optval),
1771                                             optp, (td != NULL) ? td->td_ucred :
1772                                             NULL, uproto);
1773                                         break;
1774                                 }
1775
1776                         case IPV6_2292PKTINFO:
1777                         case IPV6_2292HOPLIMIT:
1778                         case IPV6_2292HOPOPTS:
1779                         case IPV6_2292DSTOPTS:
1780                         case IPV6_2292RTHDR:
1781                                 /* RFC 2292 */
1782                                 if (optlen != sizeof(int)) {
1783                                         error = EINVAL;
1784                                         break;
1785                                 }
1786                                 error = sooptcopyin(sopt, &optval,
1787                                         sizeof optval, sizeof optval);
1788                                 if (error)
1789                                         break;
1790                                 switch (optname) {
1791                                 case IPV6_2292PKTINFO:
1792                                         OPTSET2292(IN6P_PKTINFO);
1793                                         break;
1794                                 case IPV6_2292HOPLIMIT:
1795                                         OPTSET2292(IN6P_HOPLIMIT);
1796                                         break;
1797                                 case IPV6_2292HOPOPTS:
1798                                         /*
1799                                          * Check super-user privilege.
1800                                          * See comments for IPV6_RECVHOPOPTS.
1801                                          */
1802                                         if (td != NULL) {
1803                                                 error = priv_check(td,
1804                                                     PRIV_NETINET_SETHDROPTS);
1805                                                 if (error)
1806                                                         return (error);
1807                                         }
1808                                         OPTSET2292(IN6P_HOPOPTS);
1809                                         break;
1810                                 case IPV6_2292DSTOPTS:
1811                                         if (td != NULL) {
1812                                                 error = priv_check(td,
1813                                                     PRIV_NETINET_SETHDROPTS);
1814                                                 if (error)
1815                                                         return (error);
1816                                         }
1817                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
1818                                         break;
1819                                 case IPV6_2292RTHDR:
1820                                         OPTSET2292(IN6P_RTHDR);
1821                                         break;
1822                                 }
1823                                 break;
1824                         case IPV6_PKTINFO:
1825                         case IPV6_HOPOPTS:
1826                         case IPV6_RTHDR:
1827                         case IPV6_DSTOPTS:
1828                         case IPV6_RTHDRDSTOPTS:
1829                         case IPV6_NEXTHOP:
1830                         {
1831                                 /* new advanced API (RFC3542) */
1832                                 u_char *optbuf;
1833                                 u_char optbuf_storage[MCLBYTES];
1834                                 int optlen;
1835                                 struct ip6_pktopts **optp;
1836
1837                                 /* cannot mix with RFC2292 */
1838                                 if (OPTBIT(IN6P_RFC2292)) {
1839                                         error = EINVAL;
1840                                         break;
1841                                 }
1842
1843                                 /*
1844                                  * We only ensure valsize is not too large
1845                                  * here.  Further validation will be done
1846                                  * later.
1847                                  */
1848                                 error = sooptcopyin(sopt, optbuf_storage,
1849                                     sizeof(optbuf_storage), 0);
1850                                 if (error)
1851                                         break;
1852                                 optlen = sopt->sopt_valsize;
1853                                 optbuf = optbuf_storage;
1854                                 optp = &in6p->in6p_outputopts;
1855                                 error = ip6_pcbopt(optname, optbuf, optlen,
1856                                     optp, (td != NULL) ? td->td_ucred : NULL,
1857                                     uproto);
1858                                 break;
1859                         }
1860 #undef OPTSET
1861
1862                         case IPV6_MULTICAST_IF:
1863                         case IPV6_MULTICAST_HOPS:
1864                         case IPV6_MULTICAST_LOOP:
1865                         case IPV6_JOIN_GROUP:
1866                         case IPV6_LEAVE_GROUP:
1867                         case IPV6_MSFILTER:
1868                         case MCAST_BLOCK_SOURCE:
1869                         case MCAST_UNBLOCK_SOURCE:
1870                         case MCAST_JOIN_GROUP:
1871                         case MCAST_LEAVE_GROUP:
1872                         case MCAST_JOIN_SOURCE_GROUP:
1873                         case MCAST_LEAVE_SOURCE_GROUP:
1874                                 error = ip6_setmoptions(in6p, sopt);
1875                                 break;
1876
1877                         case IPV6_PORTRANGE:
1878                                 error = sooptcopyin(sopt, &optval,
1879                                     sizeof optval, sizeof optval);
1880                                 if (error)
1881                                         break;
1882
1883                                 INP_WLOCK(in6p);
1884                                 switch (optval) {
1885                                 case IPV6_PORTRANGE_DEFAULT:
1886                                         in6p->inp_flags &= ~(INP_LOWPORT);
1887                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1888                                         break;
1889
1890                                 case IPV6_PORTRANGE_HIGH:
1891                                         in6p->inp_flags &= ~(INP_LOWPORT);
1892                                         in6p->inp_flags |= INP_HIGHPORT;
1893                                         break;
1894
1895                                 case IPV6_PORTRANGE_LOW:
1896                                         in6p->inp_flags &= ~(INP_HIGHPORT);
1897                                         in6p->inp_flags |= INP_LOWPORT;
1898                                         break;
1899
1900                                 default:
1901                                         error = EINVAL;
1902                                         break;
1903                                 }
1904                                 INP_WUNLOCK(in6p);
1905                                 break;
1906
1907 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1908                         case IPV6_IPSEC_POLICY:
1909                                 if (IPSEC_ENABLED(ipv6)) {
1910                                         error = IPSEC_PCBCTL(ipv6, in6p, sopt);
1911                                         break;
1912                                 }
1913                                 /* FALLTHROUGH */
1914 #endif /* IPSEC */
1915
1916                         default:
1917                                 error = ENOPROTOOPT;
1918                                 break;
1919                         }
1920                         break;
1921
1922                 case SOPT_GET:
1923                         switch (optname) {
1924
1925                         case IPV6_2292PKTOPTIONS:
1926 #ifdef IPV6_PKTOPTIONS
1927                         case IPV6_PKTOPTIONS:
1928 #endif
1929                                 /*
1930                                  * RFC3542 (effectively) deprecated the
1931                                  * semantics of the 2292-style pktoptions.
1932                                  * Since it was not reliable in nature (i.e.,
1933                                  * applications had to expect the lack of some
1934                                  * information after all), it would make sense
1935                                  * to simplify this part by always returning
1936                                  * empty data.
1937                                  */
1938                                 sopt->sopt_valsize = 0;
1939                                 break;
1940
1941                         case IPV6_RECVHOPOPTS:
1942                         case IPV6_RECVDSTOPTS:
1943                         case IPV6_RECVRTHDRDSTOPTS:
1944                         case IPV6_UNICAST_HOPS:
1945                         case IPV6_RECVPKTINFO:
1946                         case IPV6_RECVHOPLIMIT:
1947                         case IPV6_RECVRTHDR:
1948                         case IPV6_RECVPATHMTU:
1949
1950                         case IPV6_V6ONLY:
1951                         case IPV6_PORTRANGE:
1952                         case IPV6_RECVTCLASS:
1953                         case IPV6_AUTOFLOWLABEL:
1954                         case IPV6_BINDANY:
1955                         case IPV6_FLOWID:
1956                         case IPV6_FLOWTYPE:
1957                         case IPV6_RECVFLOWID:
1958 #ifdef  RSS
1959                         case IPV6_RSSBUCKETID:
1960                         case IPV6_RECVRSSBUCKETID:
1961 #endif
1962                         case IPV6_BINDMULTI:
1963                                 switch (optname) {
1964
1965                                 case IPV6_RECVHOPOPTS:
1966                                         optval = OPTBIT(IN6P_HOPOPTS);
1967                                         break;
1968
1969                                 case IPV6_RECVDSTOPTS:
1970                                         optval = OPTBIT(IN6P_DSTOPTS);
1971                                         break;
1972
1973                                 case IPV6_RECVRTHDRDSTOPTS:
1974                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
1975                                         break;
1976
1977                                 case IPV6_UNICAST_HOPS:
1978                                         optval = in6p->in6p_hops;
1979                                         break;
1980
1981                                 case IPV6_RECVPKTINFO:
1982                                         optval = OPTBIT(IN6P_PKTINFO);
1983                                         break;
1984
1985                                 case IPV6_RECVHOPLIMIT:
1986                                         optval = OPTBIT(IN6P_HOPLIMIT);
1987                                         break;
1988
1989                                 case IPV6_RECVRTHDR:
1990                                         optval = OPTBIT(IN6P_RTHDR);
1991                                         break;
1992
1993                                 case IPV6_RECVPATHMTU:
1994                                         optval = OPTBIT(IN6P_MTU);
1995                                         break;
1996
1997                                 case IPV6_V6ONLY:
1998                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
1999                                         break;
2000
2001                                 case IPV6_PORTRANGE:
2002                                     {
2003                                         int flags;
2004                                         flags = in6p->inp_flags;
2005                                         if (flags & INP_HIGHPORT)
2006                                                 optval = IPV6_PORTRANGE_HIGH;
2007                                         else if (flags & INP_LOWPORT)
2008                                                 optval = IPV6_PORTRANGE_LOW;
2009                                         else
2010                                                 optval = 0;
2011                                         break;
2012                                     }
2013                                 case IPV6_RECVTCLASS:
2014                                         optval = OPTBIT(IN6P_TCLASS);
2015                                         break;
2016
2017                                 case IPV6_AUTOFLOWLABEL:
2018                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2019                                         break;
2020
2021                                 case IPV6_ORIGDSTADDR:
2022                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2023                                         break;
2024
2025                                 case IPV6_BINDANY:
2026                                         optval = OPTBIT(INP_BINDANY);
2027                                         break;
2028
2029                                 case IPV6_FLOWID:
2030                                         optval = in6p->inp_flowid;
2031                                         break;
2032
2033                                 case IPV6_FLOWTYPE:
2034                                         optval = in6p->inp_flowtype;
2035                                         break;
2036
2037                                 case IPV6_RECVFLOWID:
2038                                         optval = OPTBIT2(INP_RECVFLOWID);
2039                                         break;
2040 #ifdef  RSS
2041                                 case IPV6_RSSBUCKETID:
2042                                         retval =
2043                                             rss_hash2bucket(in6p->inp_flowid,
2044                                             in6p->inp_flowtype,
2045                                             &rss_bucket);
2046                                         if (retval == 0)
2047                                                 optval = rss_bucket;
2048                                         else
2049                                                 error = EINVAL;
2050                                         break;
2051
2052                                 case IPV6_RECVRSSBUCKETID:
2053                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2054                                         break;
2055 #endif
2056
2057                                 case IPV6_BINDMULTI:
2058                                         optval = OPTBIT2(INP_BINDMULTI);
2059                                         break;
2060
2061                                 }
2062                                 if (error)
2063                                         break;
2064                                 error = sooptcopyout(sopt, &optval,
2065                                         sizeof optval);
2066                                 break;
2067
2068                         case IPV6_PATHMTU:
2069                         {
2070                                 u_long pmtu = 0;
2071                                 struct ip6_mtuinfo mtuinfo;
2072
2073                                 if (!(so->so_state & SS_ISCONNECTED))
2074                                         return (ENOTCONN);
2075                                 /*
2076                                  * XXX: we dot not consider the case of source
2077                                  * routing, or optional information to specify
2078                                  * the outgoing interface.
2079                                  */
2080                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2081                                     &in6p->in6p_faddr, &pmtu);
2082                                 if (error)
2083                                         break;
2084                                 if (pmtu > IPV6_MAXPACKET)
2085                                         pmtu = IPV6_MAXPACKET;
2086
2087                                 bzero(&mtuinfo, sizeof(mtuinfo));
2088                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2089                                 optdata = (void *)&mtuinfo;
2090                                 optdatalen = sizeof(mtuinfo);
2091                                 error = sooptcopyout(sopt, optdata,
2092                                     optdatalen);
2093                                 break;
2094                         }
2095
2096                         case IPV6_2292PKTINFO:
2097                         case IPV6_2292HOPLIMIT:
2098                         case IPV6_2292HOPOPTS:
2099                         case IPV6_2292RTHDR:
2100                         case IPV6_2292DSTOPTS:
2101                                 switch (optname) {
2102                                 case IPV6_2292PKTINFO:
2103                                         optval = OPTBIT(IN6P_PKTINFO);
2104                                         break;
2105                                 case IPV6_2292HOPLIMIT:
2106                                         optval = OPTBIT(IN6P_HOPLIMIT);
2107                                         break;
2108                                 case IPV6_2292HOPOPTS:
2109                                         optval = OPTBIT(IN6P_HOPOPTS);
2110                                         break;
2111                                 case IPV6_2292RTHDR:
2112                                         optval = OPTBIT(IN6P_RTHDR);
2113                                         break;
2114                                 case IPV6_2292DSTOPTS:
2115                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2116                                         break;
2117                                 }
2118                                 error = sooptcopyout(sopt, &optval,
2119                                     sizeof optval);
2120                                 break;
2121                         case IPV6_PKTINFO:
2122                         case IPV6_HOPOPTS:
2123                         case IPV6_RTHDR:
2124                         case IPV6_DSTOPTS:
2125                         case IPV6_RTHDRDSTOPTS:
2126                         case IPV6_NEXTHOP:
2127                         case IPV6_TCLASS:
2128                         case IPV6_DONTFRAG:
2129                         case IPV6_USE_MIN_MTU:
2130                         case IPV6_PREFER_TEMPADDR:
2131                                 error = ip6_getpcbopt(in6p->in6p_outputopts,
2132                                     optname, sopt);
2133                                 break;
2134
2135                         case IPV6_MULTICAST_IF:
2136                         case IPV6_MULTICAST_HOPS:
2137                         case IPV6_MULTICAST_LOOP:
2138                         case IPV6_MSFILTER:
2139                                 error = ip6_getmoptions(in6p, sopt);
2140                                 break;
2141
2142 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2143                         case IPV6_IPSEC_POLICY:
2144                                 if (IPSEC_ENABLED(ipv6)) {
2145                                         error = IPSEC_PCBCTL(ipv6, in6p, sopt);
2146                                         break;
2147                                 }
2148                                 /* FALLTHROUGH */
2149 #endif /* IPSEC */
2150                         default:
2151                                 error = ENOPROTOOPT;
2152                                 break;
2153                         }
2154                         break;
2155                 }
2156         }
2157         return (error);
2158 }
2159
2160 int
2161 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2162 {
2163         int error = 0, optval, optlen;
2164         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2165         struct inpcb *in6p = sotoinpcb(so);
2166         int level, op, optname;
2167
2168         level = sopt->sopt_level;
2169         op = sopt->sopt_dir;
2170         optname = sopt->sopt_name;
2171         optlen = sopt->sopt_valsize;
2172
2173         if (level != IPPROTO_IPV6) {
2174                 return (EINVAL);
2175         }
2176
2177         switch (optname) {
2178         case IPV6_CHECKSUM:
2179                 /*
2180                  * For ICMPv6 sockets, no modification allowed for checksum
2181                  * offset, permit "no change" values to help existing apps.
2182                  *
2183                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2184                  * for an ICMPv6 socket will fail."
2185                  * The current behavior does not meet RFC3542.
2186                  */
2187                 switch (op) {
2188                 case SOPT_SET:
2189                         if (optlen != sizeof(int)) {
2190                                 error = EINVAL;
2191                                 break;
2192                         }
2193                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2194                                             sizeof(optval));
2195                         if (error)
2196                                 break;
2197                         if ((optval % 2) != 0) {
2198                                 /* the API assumes even offset values */
2199                                 error = EINVAL;
2200                         } else if (so->so_proto->pr_protocol ==
2201                             IPPROTO_ICMPV6) {
2202                                 if (optval != icmp6off)
2203                                         error = EINVAL;
2204                         } else
2205                                 in6p->in6p_cksum = optval;
2206                         break;
2207
2208                 case SOPT_GET:
2209                         if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
2210                                 optval = icmp6off;
2211                         else
2212                                 optval = in6p->in6p_cksum;
2213
2214                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2215                         break;
2216
2217                 default:
2218                         error = EINVAL;
2219                         break;
2220                 }
2221                 break;
2222
2223         default:
2224                 error = ENOPROTOOPT;
2225                 break;
2226         }
2227
2228         return (error);
2229 }
2230
2231 /*
2232  * Set up IP6 options in pcb for insertion in output packets or
2233  * specifying behavior of outgoing packets.
2234  */
2235 static int
2236 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2237     struct socket *so, struct sockopt *sopt)
2238 {
2239         struct ip6_pktopts *opt = *pktopt;
2240         int error = 0;
2241         struct thread *td = sopt->sopt_td;
2242
2243         /* turn off any old options. */
2244         if (opt) {
2245 #ifdef DIAGNOSTIC
2246                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2247                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2248                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2249                         printf("ip6_pcbopts: all specified options are cleared.\n");
2250 #endif
2251                 ip6_clearpktopts(opt, -1);
2252         } else
2253                 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
2254         *pktopt = NULL;
2255
2256         if (!m || m->m_len == 0) {
2257                 /*
2258                  * Only turning off any previous options, regardless of
2259                  * whether the opt is just created or given.
2260                  */
2261                 free(opt, M_IP6OPT);
2262                 return (0);
2263         }
2264
2265         /*  set options specified by user. */
2266         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2267             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2268                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2269                 free(opt, M_IP6OPT);
2270                 return (error);
2271         }
2272         *pktopt = opt;
2273         return (0);
2274 }
2275
2276 /*
2277  * initialize ip6_pktopts.  beware that there are non-zero default values in
2278  * the struct.
2279  */
2280 void
2281 ip6_initpktopts(struct ip6_pktopts *opt)
2282 {
2283
2284         bzero(opt, sizeof(*opt));
2285         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2286         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2287         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2288         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2289 }
2290
2291 static int
2292 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2293     struct ucred *cred, int uproto)
2294 {
2295         struct ip6_pktopts *opt;
2296
2297         if (*pktopt == NULL) {
2298                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2299                     M_WAITOK);
2300                 ip6_initpktopts(*pktopt);
2301         }
2302         opt = *pktopt;
2303
2304         return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto));
2305 }
2306
2307 static int
2308 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt)
2309 {
2310         void *optdata = NULL;
2311         int optdatalen = 0;
2312         struct ip6_ext *ip6e;
2313         int error = 0;
2314         struct in6_pktinfo null_pktinfo;
2315         int deftclass = 0, on;
2316         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2317         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2318
2319         switch (optname) {
2320         case IPV6_PKTINFO:
2321                 optdata = (void *)&null_pktinfo;
2322                 if (pktopt && pktopt->ip6po_pktinfo) {
2323                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2324                             sizeof(null_pktinfo));
2325                         in6_clearscope(&null_pktinfo.ipi6_addr);
2326                 } else {
2327                         /* XXX: we don't have to do this every time... */
2328                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2329                 }
2330                 optdatalen = sizeof(struct in6_pktinfo);
2331                 break;
2332         case IPV6_TCLASS:
2333                 if (pktopt && pktopt->ip6po_tclass >= 0)
2334                         optdata = (void *)&pktopt->ip6po_tclass;
2335                 else
2336                         optdata = (void *)&deftclass;
2337                 optdatalen = sizeof(int);
2338                 break;
2339         case IPV6_HOPOPTS:
2340                 if (pktopt && pktopt->ip6po_hbh) {
2341                         optdata = (void *)pktopt->ip6po_hbh;
2342                         ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
2343                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2344                 }
2345                 break;
2346         case IPV6_RTHDR:
2347                 if (pktopt && pktopt->ip6po_rthdr) {
2348                         optdata = (void *)pktopt->ip6po_rthdr;
2349                         ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
2350                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2351                 }
2352                 break;
2353         case IPV6_RTHDRDSTOPTS:
2354                 if (pktopt && pktopt->ip6po_dest1) {
2355                         optdata = (void *)pktopt->ip6po_dest1;
2356                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
2357                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2358                 }
2359                 break;
2360         case IPV6_DSTOPTS:
2361                 if (pktopt && pktopt->ip6po_dest2) {
2362                         optdata = (void *)pktopt->ip6po_dest2;
2363                         ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
2364                         optdatalen = (ip6e->ip6e_len + 1) << 3;
2365                 }
2366                 break;
2367         case IPV6_NEXTHOP:
2368                 if (pktopt && pktopt->ip6po_nexthop) {
2369                         optdata = (void *)pktopt->ip6po_nexthop;
2370                         optdatalen = pktopt->ip6po_nexthop->sa_len;
2371                 }
2372                 break;
2373         case IPV6_USE_MIN_MTU:
2374                 if (pktopt)
2375                         optdata = (void *)&pktopt->ip6po_minmtu;
2376                 else
2377                         optdata = (void *)&defminmtu;
2378                 optdatalen = sizeof(int);
2379                 break;
2380         case IPV6_DONTFRAG:
2381                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2382                         on = 1;
2383                 else
2384                         on = 0;
2385                 optdata = (void *)&on;
2386                 optdatalen = sizeof(on);
2387                 break;
2388         case IPV6_PREFER_TEMPADDR:
2389                 if (pktopt)
2390                         optdata = (void *)&pktopt->ip6po_prefer_tempaddr;
2391                 else
2392                         optdata = (void *)&defpreftemp;
2393                 optdatalen = sizeof(int);
2394                 break;
2395         default:                /* should not happen */
2396 #ifdef DIAGNOSTIC
2397                 panic("ip6_getpcbopt: unexpected option\n");
2398 #endif
2399                 return (ENOPROTOOPT);
2400         }
2401
2402         error = sooptcopyout(sopt, optdata, optdatalen);
2403
2404         return (error);
2405 }
2406
2407 void
2408 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2409 {
2410         if (pktopt == NULL)
2411                 return;
2412
2413         if (optname == -1 || optname == IPV6_PKTINFO) {
2414                 if (pktopt->ip6po_pktinfo)
2415                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2416                 pktopt->ip6po_pktinfo = NULL;
2417         }
2418         if (optname == -1 || optname == IPV6_HOPLIMIT)
2419                 pktopt->ip6po_hlim = -1;
2420         if (optname == -1 || optname == IPV6_TCLASS)
2421                 pktopt->ip6po_tclass = -1;
2422         if (optname == -1 || optname == IPV6_NEXTHOP) {
2423                 if (pktopt->ip6po_nextroute.ro_rt) {
2424                         RTFREE(pktopt->ip6po_nextroute.ro_rt);
2425                         pktopt->ip6po_nextroute.ro_rt = NULL;
2426                 }
2427                 if (pktopt->ip6po_nexthop)
2428                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2429                 pktopt->ip6po_nexthop = NULL;
2430         }
2431         if (optname == -1 || optname == IPV6_HOPOPTS) {
2432                 if (pktopt->ip6po_hbh)
2433                         free(pktopt->ip6po_hbh, M_IP6OPT);
2434                 pktopt->ip6po_hbh = NULL;
2435         }
2436         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2437                 if (pktopt->ip6po_dest1)
2438                         free(pktopt->ip6po_dest1, M_IP6OPT);
2439                 pktopt->ip6po_dest1 = NULL;
2440         }
2441         if (optname == -1 || optname == IPV6_RTHDR) {
2442                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2443                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2444                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2445                 if (pktopt->ip6po_route.ro_rt) {
2446                         RTFREE(pktopt->ip6po_route.ro_rt);
2447                         pktopt->ip6po_route.ro_rt = NULL;
2448                 }
2449         }
2450         if (optname == -1 || optname == IPV6_DSTOPTS) {
2451                 if (pktopt->ip6po_dest2)
2452                         free(pktopt->ip6po_dest2, M_IP6OPT);
2453                 pktopt->ip6po_dest2 = NULL;
2454         }
2455 }
2456
2457 #define PKTOPT_EXTHDRCPY(type) \
2458 do {\
2459         if (src->type) {\
2460                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2461                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2462                 if (dst->type == NULL)\
2463                         goto bad;\
2464                 bcopy(src->type, dst->type, hlen);\
2465         }\
2466 } while (/*CONSTCOND*/ 0)
2467
2468 static int
2469 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2470 {
2471         if (dst == NULL || src == NULL)  {
2472                 printf("ip6_clearpktopts: invalid argument\n");
2473                 return (EINVAL);
2474         }
2475
2476         dst->ip6po_hlim = src->ip6po_hlim;
2477         dst->ip6po_tclass = src->ip6po_tclass;
2478         dst->ip6po_flags = src->ip6po_flags;
2479         dst->ip6po_minmtu = src->ip6po_minmtu;
2480         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2481         if (src->ip6po_pktinfo) {
2482                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2483                     M_IP6OPT, canwait);
2484                 if (dst->ip6po_pktinfo == NULL)
2485                         goto bad;
2486                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2487         }
2488         if (src->ip6po_nexthop) {
2489                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2490                     M_IP6OPT, canwait);
2491                 if (dst->ip6po_nexthop == NULL)
2492                         goto bad;
2493                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2494                     src->ip6po_nexthop->sa_len);
2495         }
2496         PKTOPT_EXTHDRCPY(ip6po_hbh);
2497         PKTOPT_EXTHDRCPY(ip6po_dest1);
2498         PKTOPT_EXTHDRCPY(ip6po_dest2);
2499         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2500         return (0);
2501
2502   bad:
2503         ip6_clearpktopts(dst, -1);
2504         return (ENOBUFS);
2505 }
2506 #undef PKTOPT_EXTHDRCPY
2507
2508 struct ip6_pktopts *
2509 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2510 {
2511         int error;
2512         struct ip6_pktopts *dst;
2513
2514         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2515         if (dst == NULL)
2516                 return (NULL);
2517         ip6_initpktopts(dst);
2518
2519         if ((error = copypktopts(dst, src, canwait)) != 0) {
2520                 free(dst, M_IP6OPT);
2521                 return (NULL);
2522         }
2523
2524         return (dst);
2525 }
2526
2527 void
2528 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2529 {
2530         if (pktopt == NULL)
2531                 return;
2532
2533         ip6_clearpktopts(pktopt, -1);
2534
2535         free(pktopt, M_IP6OPT);
2536 }
2537
2538 /*
2539  * Set IPv6 outgoing packet options based on advanced API.
2540  */
2541 int
2542 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2543     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2544 {
2545         struct cmsghdr *cm = NULL;
2546
2547         if (control == NULL || opt == NULL)
2548                 return (EINVAL);
2549
2550         ip6_initpktopts(opt);
2551         if (stickyopt) {
2552                 int error;
2553
2554                 /*
2555                  * If stickyopt is provided, make a local copy of the options
2556                  * for this particular packet, then override them by ancillary
2557                  * objects.
2558                  * XXX: copypktopts() does not copy the cached route to a next
2559                  * hop (if any).  This is not very good in terms of efficiency,
2560                  * but we can allow this since this option should be rarely
2561                  * used.
2562                  */
2563                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2564                         return (error);
2565         }
2566
2567         /*
2568          * XXX: Currently, we assume all the optional information is stored
2569          * in a single mbuf.
2570          */
2571         if (control->m_next)
2572                 return (EINVAL);
2573
2574         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2575             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2576                 int error;
2577
2578                 if (control->m_len < CMSG_LEN(0))
2579                         return (EINVAL);
2580
2581                 cm = mtod(control, struct cmsghdr *);
2582                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2583                         return (EINVAL);
2584                 if (cm->cmsg_level != IPPROTO_IPV6)
2585                         continue;
2586
2587                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2588                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2589                 if (error)
2590                         return (error);
2591         }
2592
2593         return (0);
2594 }
2595
2596 /*
2597  * Set a particular packet option, as a sticky option or an ancillary data
2598  * item.  "len" can be 0 only when it's a sticky option.
2599  * We have 4 cases of combination of "sticky" and "cmsg":
2600  * "sticky=0, cmsg=0": impossible
2601  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2602  * "sticky=1, cmsg=0": RFC3542 socket option
2603  * "sticky=1, cmsg=1": RFC2292 socket option
2604  */
2605 static int
2606 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2607     struct ucred *cred, int sticky, int cmsg, int uproto)
2608 {
2609         int minmtupolicy, preftemp;
2610         int error;
2611
2612         if (!sticky && !cmsg) {
2613 #ifdef DIAGNOSTIC
2614                 printf("ip6_setpktopt: impossible case\n");
2615 #endif
2616                 return (EINVAL);
2617         }
2618
2619         /*
2620          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2621          * not be specified in the context of RFC3542.  Conversely,
2622          * RFC3542 types should not be specified in the context of RFC2292.
2623          */
2624         if (!cmsg) {
2625                 switch (optname) {
2626                 case IPV6_2292PKTINFO:
2627                 case IPV6_2292HOPLIMIT:
2628                 case IPV6_2292NEXTHOP:
2629                 case IPV6_2292HOPOPTS:
2630                 case IPV6_2292DSTOPTS:
2631                 case IPV6_2292RTHDR:
2632                 case IPV6_2292PKTOPTIONS:
2633                         return (ENOPROTOOPT);
2634                 }
2635         }
2636         if (sticky && cmsg) {
2637                 switch (optname) {
2638                 case IPV6_PKTINFO:
2639                 case IPV6_HOPLIMIT:
2640                 case IPV6_NEXTHOP:
2641                 case IPV6_HOPOPTS:
2642                 case IPV6_DSTOPTS:
2643                 case IPV6_RTHDRDSTOPTS:
2644                 case IPV6_RTHDR:
2645                 case IPV6_USE_MIN_MTU:
2646                 case IPV6_DONTFRAG:
2647                 case IPV6_TCLASS:
2648                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2649                         return (ENOPROTOOPT);
2650                 }
2651         }
2652
2653         switch (optname) {
2654         case IPV6_2292PKTINFO:
2655         case IPV6_PKTINFO:
2656         {
2657                 struct ifnet *ifp = NULL;
2658                 struct in6_pktinfo *pktinfo;
2659
2660                 if (len != sizeof(struct in6_pktinfo))
2661                         return (EINVAL);
2662
2663                 pktinfo = (struct in6_pktinfo *)buf;
2664
2665                 /*
2666                  * An application can clear any sticky IPV6_PKTINFO option by
2667                  * doing a "regular" setsockopt with ipi6_addr being
2668                  * in6addr_any and ipi6_ifindex being zero.
2669                  * [RFC 3542, Section 6]
2670                  */
2671                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2672                     pktinfo->ipi6_ifindex == 0 &&
2673                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2674                         ip6_clearpktopts(opt, optname);
2675                         break;
2676                 }
2677
2678                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2679                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2680                         return (EINVAL);
2681                 }
2682                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2683                         return (EINVAL);
2684                 /* validate the interface index if specified. */
2685                 if (pktinfo->ipi6_ifindex > V_if_index)
2686                          return (ENXIO);
2687                 if (pktinfo->ipi6_ifindex) {
2688                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2689                         if (ifp == NULL)
2690                                 return (ENXIO);
2691                 }
2692                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2693                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2694                         return (ENETDOWN);
2695
2696                 if (ifp != NULL &&
2697                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2698                         struct in6_ifaddr *ia;
2699
2700                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2701                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2702                         if (ia == NULL)
2703                                 return (EADDRNOTAVAIL);
2704                         ifa_free(&ia->ia_ifa);
2705                 }
2706                 /*
2707                  * We store the address anyway, and let in6_selectsrc()
2708                  * validate the specified address.  This is because ipi6_addr
2709                  * may not have enough information about its scope zone, and
2710                  * we may need additional information (such as outgoing
2711                  * interface or the scope zone of a destination address) to
2712                  * disambiguate the scope.
2713                  * XXX: the delay of the validation may confuse the
2714                  * application when it is used as a sticky option.
2715                  */
2716                 if (opt->ip6po_pktinfo == NULL) {
2717                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2718                             M_IP6OPT, M_NOWAIT);
2719                         if (opt->ip6po_pktinfo == NULL)
2720                                 return (ENOBUFS);
2721                 }
2722                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2723                 break;
2724         }
2725
2726         case IPV6_2292HOPLIMIT:
2727         case IPV6_HOPLIMIT:
2728         {
2729                 int *hlimp;
2730
2731                 /*
2732                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2733                  * to simplify the ordering among hoplimit options.
2734                  */
2735                 if (optname == IPV6_HOPLIMIT && sticky)
2736                         return (ENOPROTOOPT);
2737
2738                 if (len != sizeof(int))
2739                         return (EINVAL);
2740                 hlimp = (int *)buf;
2741                 if (*hlimp < -1 || *hlimp > 255)
2742                         return (EINVAL);
2743
2744                 opt->ip6po_hlim = *hlimp;
2745                 break;
2746         }
2747
2748         case IPV6_TCLASS:
2749         {
2750                 int tclass;
2751
2752                 if (len != sizeof(int))
2753                         return (EINVAL);
2754                 tclass = *(int *)buf;
2755                 if (tclass < -1 || tclass > 255)
2756                         return (EINVAL);
2757
2758                 opt->ip6po_tclass = tclass;
2759                 break;
2760         }
2761
2762         case IPV6_2292NEXTHOP:
2763         case IPV6_NEXTHOP:
2764                 if (cred != NULL) {
2765                         error = priv_check_cred(cred,
2766                             PRIV_NETINET_SETHDROPTS, 0);
2767                         if (error)
2768                                 return (error);
2769                 }
2770
2771                 if (len == 0) { /* just remove the option */
2772                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
2773                         break;
2774                 }
2775
2776                 /* check if cmsg_len is large enough for sa_len */
2777                 if (len < sizeof(struct sockaddr) || len < *buf)
2778                         return (EINVAL);
2779
2780                 switch (((struct sockaddr *)buf)->sa_family) {
2781                 case AF_INET6:
2782                 {
2783                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
2784                         int error;
2785
2786                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
2787                                 return (EINVAL);
2788
2789                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
2790                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
2791                                 return (EINVAL);
2792                         }
2793                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
2794                             != 0) {
2795                                 return (error);
2796                         }
2797                         break;
2798                 }
2799                 case AF_LINK:   /* should eventually be supported */
2800                 default:
2801                         return (EAFNOSUPPORT);
2802                 }
2803
2804                 /* turn off the previous option, then set the new option. */
2805                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
2806                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
2807                 if (opt->ip6po_nexthop == NULL)
2808                         return (ENOBUFS);
2809                 bcopy(buf, opt->ip6po_nexthop, *buf);
2810                 break;
2811
2812         case IPV6_2292HOPOPTS:
2813         case IPV6_HOPOPTS:
2814         {
2815                 struct ip6_hbh *hbh;
2816                 int hbhlen;
2817
2818                 /*
2819                  * XXX: We don't allow a non-privileged user to set ANY HbH
2820                  * options, since per-option restriction has too much
2821                  * overhead.
2822                  */
2823                 if (cred != NULL) {
2824                         error = priv_check_cred(cred,
2825                             PRIV_NETINET_SETHDROPTS, 0);
2826                         if (error)
2827                                 return (error);
2828                 }
2829
2830                 if (len == 0) {
2831                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
2832                         break;  /* just remove the option */
2833                 }
2834
2835                 /* message length validation */
2836                 if (len < sizeof(struct ip6_hbh))
2837                         return (EINVAL);
2838                 hbh = (struct ip6_hbh *)buf;
2839                 hbhlen = (hbh->ip6h_len + 1) << 3;
2840                 if (len != hbhlen)
2841                         return (EINVAL);
2842
2843                 /* turn off the previous option, then set the new option. */
2844                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
2845                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
2846                 if (opt->ip6po_hbh == NULL)
2847                         return (ENOBUFS);
2848                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
2849
2850                 break;
2851         }
2852
2853         case IPV6_2292DSTOPTS:
2854         case IPV6_DSTOPTS:
2855         case IPV6_RTHDRDSTOPTS:
2856         {
2857                 struct ip6_dest *dest, **newdest = NULL;
2858                 int destlen;
2859
2860                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
2861                         error = priv_check_cred(cred,
2862                             PRIV_NETINET_SETHDROPTS, 0);
2863                         if (error)
2864                                 return (error);
2865                 }
2866
2867                 if (len == 0) {
2868                         ip6_clearpktopts(opt, optname);
2869                         break;  /* just remove the option */
2870                 }
2871
2872                 /* message length validation */
2873                 if (len < sizeof(struct ip6_dest))
2874                         return (EINVAL);
2875                 dest = (struct ip6_dest *)buf;
2876                 destlen = (dest->ip6d_len + 1) << 3;
2877                 if (len != destlen)
2878                         return (EINVAL);
2879
2880                 /*
2881                  * Determine the position that the destination options header
2882                  * should be inserted; before or after the routing header.
2883                  */
2884                 switch (optname) {
2885                 case IPV6_2292DSTOPTS:
2886                         /*
2887                          * The old advacned API is ambiguous on this point.
2888                          * Our approach is to determine the position based
2889                          * according to the existence of a routing header.
2890                          * Note, however, that this depends on the order of the
2891                          * extension headers in the ancillary data; the 1st
2892                          * part of the destination options header must appear
2893                          * before the routing header in the ancillary data,
2894                          * too.
2895                          * RFC3542 solved the ambiguity by introducing
2896                          * separate ancillary data or option types.
2897                          */
2898                         if (opt->ip6po_rthdr == NULL)
2899                                 newdest = &opt->ip6po_dest1;
2900                         else
2901                                 newdest = &opt->ip6po_dest2;
2902                         break;
2903                 case IPV6_RTHDRDSTOPTS:
2904                         newdest = &opt->ip6po_dest1;
2905                         break;
2906                 case IPV6_DSTOPTS:
2907                         newdest = &opt->ip6po_dest2;
2908                         break;
2909                 }
2910
2911                 /* turn off the previous option, then set the new option. */
2912                 ip6_clearpktopts(opt, optname);
2913                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
2914                 if (*newdest == NULL)
2915                         return (ENOBUFS);
2916                 bcopy(dest, *newdest, destlen);
2917
2918                 break;
2919         }
2920
2921         case IPV6_2292RTHDR:
2922         case IPV6_RTHDR:
2923         {
2924                 struct ip6_rthdr *rth;
2925                 int rthlen;
2926
2927                 if (len == 0) {
2928                         ip6_clearpktopts(opt, IPV6_RTHDR);
2929                         break;  /* just remove the option */
2930                 }
2931
2932                 /* message length validation */
2933                 if (len < sizeof(struct ip6_rthdr))
2934                         return (EINVAL);
2935                 rth = (struct ip6_rthdr *)buf;
2936                 rthlen = (rth->ip6r_len + 1) << 3;
2937                 if (len != rthlen)
2938                         return (EINVAL);
2939
2940                 switch (rth->ip6r_type) {
2941                 case IPV6_RTHDR_TYPE_0:
2942                         if (rth->ip6r_len == 0) /* must contain one addr */
2943                                 return (EINVAL);
2944                         if (rth->ip6r_len % 2) /* length must be even */
2945                                 return (EINVAL);
2946                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
2947                                 return (EINVAL);
2948                         break;
2949                 default:
2950                         return (EINVAL);        /* not supported */
2951                 }
2952
2953                 /* turn off the previous option */
2954                 ip6_clearpktopts(opt, IPV6_RTHDR);
2955                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
2956                 if (opt->ip6po_rthdr == NULL)
2957                         return (ENOBUFS);
2958                 bcopy(rth, opt->ip6po_rthdr, rthlen);
2959
2960                 break;
2961         }
2962
2963         case IPV6_USE_MIN_MTU:
2964                 if (len != sizeof(int))
2965                         return (EINVAL);
2966                 minmtupolicy = *(int *)buf;
2967                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
2968                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
2969                     minmtupolicy != IP6PO_MINMTU_ALL) {
2970                         return (EINVAL);
2971                 }
2972                 opt->ip6po_minmtu = minmtupolicy;
2973                 break;
2974
2975         case IPV6_DONTFRAG:
2976                 if (len != sizeof(int))
2977                         return (EINVAL);
2978
2979                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
2980                         /*
2981                          * we ignore this option for TCP sockets.
2982                          * (RFC3542 leaves this case unspecified.)
2983                          */
2984                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
2985                 } else
2986                         opt->ip6po_flags |= IP6PO_DONTFRAG;
2987                 break;
2988
2989         case IPV6_PREFER_TEMPADDR:
2990                 if (len != sizeof(int))
2991                         return (EINVAL);
2992                 preftemp = *(int *)buf;
2993                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
2994                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
2995                     preftemp != IP6PO_TEMPADDR_PREFER) {
2996                         return (EINVAL);
2997                 }
2998                 opt->ip6po_prefer_tempaddr = preftemp;
2999                 break;
3000
3001         default:
3002                 return (ENOPROTOOPT);
3003         } /* end of switch */
3004
3005         return (0);
3006 }
3007
3008 /*
3009  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3010  * packet to the input queue of a specified interface.  Note that this
3011  * calls the output routine of the loopback "driver", but with an interface
3012  * pointer that might NOT be &loif -- easier than replicating that code here.
3013  */
3014 void
3015 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3016 {
3017         struct mbuf *copym;
3018         struct ip6_hdr *ip6;
3019
3020         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3021         if (copym == NULL)
3022                 return;
3023
3024         /*
3025          * Make sure to deep-copy IPv6 header portion in case the data
3026          * is in an mbuf cluster, so that we can safely override the IPv6
3027          * header portion later.
3028          */
3029         if (!M_WRITABLE(copym) ||
3030             copym->m_len < sizeof(struct ip6_hdr)) {
3031                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3032                 if (copym == NULL)
3033                         return;
3034         }
3035         ip6 = mtod(copym, struct ip6_hdr *);
3036         /*
3037          * clear embedded scope identifiers if necessary.
3038          * in6_clearscope will touch the addresses only when necessary.
3039          */
3040         in6_clearscope(&ip6->ip6_src);
3041         in6_clearscope(&ip6->ip6_dst);
3042         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3043                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3044                     CSUM_PSEUDO_HDR;
3045                 copym->m_pkthdr.csum_data = 0xffff;
3046         }
3047         if_simloop(ifp, copym, AF_INET6, 0);
3048 }
3049
3050 /*
3051  * Chop IPv6 header off from the payload.
3052  */
3053 static int
3054 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3055 {
3056         struct mbuf *mh;
3057         struct ip6_hdr *ip6;
3058
3059         ip6 = mtod(m, struct ip6_hdr *);
3060         if (m->m_len > sizeof(*ip6)) {
3061                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3062                 if (mh == NULL) {
3063                         m_freem(m);
3064                         return ENOBUFS;
3065                 }
3066                 m_move_pkthdr(mh, m);
3067                 M_ALIGN(mh, sizeof(*ip6));
3068                 m->m_len -= sizeof(*ip6);
3069                 m->m_data += sizeof(*ip6);
3070                 mh->m_next = m;
3071                 m = mh;
3072                 m->m_len = sizeof(*ip6);
3073                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3074         }
3075         exthdrs->ip6e_ip6 = m;
3076         return 0;
3077 }
3078
3079 /*
3080  * Compute IPv6 extension header length.
3081  */
3082 int
3083 ip6_optlen(struct inpcb *in6p)
3084 {
3085         int len;
3086
3087         if (!in6p->in6p_outputopts)
3088                 return 0;
3089
3090         len = 0;
3091 #define elen(x) \
3092     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3093
3094         len += elen(in6p->in6p_outputopts->ip6po_hbh);
3095         if (in6p->in6p_outputopts->ip6po_rthdr)
3096                 /* dest1 is valid with rthdr only */
3097                 len += elen(in6p->in6p_outputopts->ip6po_dest1);
3098         len += elen(in6p->in6p_outputopts->ip6po_rthdr);
3099         len += elen(in6p->in6p_outputopts->ip6po_dest2);
3100         return len;
3101 #undef elen
3102 }