1 /* $NetBSD: ip6_output.c,v 1.165 2015/04/27 10:14:44 ozaki-r Exp $ */ 2 /* $KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1988, 1990, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 62 */ 63 64 #include <sys/cdefs.h> 65 __KERNEL_RCSID(0, "$NetBSD: ip6_output.c,v 1.165 2015/04/27 10:14:44 ozaki-r Exp $"); 66 67 #include "opt_inet.h" 68 #include "opt_inet6.h" 69 #include "opt_ipsec.h" 70 71 #include <sys/param.h> 72 #include <sys/malloc.h> 73 #include <sys/mbuf.h> 74 #include <sys/errno.h> 75 #include <sys/protosw.h> 76 #include <sys/socket.h> 77 #include <sys/socketvar.h> 78 #include <sys/systm.h> 79 #include <sys/proc.h> 80 #include <sys/kauth.h> 81 82 #include <net/if.h> 83 #include <net/route.h> 84 #include <net/pfil.h> 85 86 #include <netinet/in.h> 87 #include <netinet/in_var.h> 88 #include <netinet/ip6.h> 89 #include <netinet/ip_var.h> 90 #include <netinet/icmp6.h> 91 #include <netinet/in_offload.h> 92 #include <netinet/portalgo.h> 93 #include <netinet6/in6_offload.h> 94 #include <netinet6/ip6_var.h> 95 #include <netinet6/ip6_private.h> 96 #include <netinet6/in6_pcb.h> 97 #include <netinet6/nd6.h> 98 #include <netinet6/ip6protosw.h> 99 #include <netinet6/scope6_var.h> 100 101 #ifdef IPSEC 102 #include <netipsec/ipsec.h> 103 #include <netipsec/ipsec6.h> 104 #include <netipsec/key.h> 105 #include <netipsec/xform.h> 106 #endif 107 108 109 #include <net/net_osdep.h> 110 111 extern pfil_head_t *inet6_pfil_hook; /* XXX */ 112 113 struct ip6_exthdrs { 114 struct mbuf *ip6e_ip6; 115 struct mbuf *ip6e_hbh; 116 struct mbuf *ip6e_dest1; 117 struct mbuf *ip6e_rthdr; 118 struct mbuf *ip6e_dest2; 119 }; 120 121 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, 122 kauth_cred_t, int); 123 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *); 124 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, kauth_cred_t, 125 int, int, int); 126 static int ip6_setmoptions(const struct sockopt *, struct in6pcb *); 127 static int ip6_getmoptions(struct sockopt *, struct in6pcb *); 128 static int ip6_copyexthdr(struct mbuf **, void *, int); 129 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int, 130 struct ip6_frag **); 131 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t); 132 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *); 133 static int ip6_getpmtu(struct route *, struct route *, struct ifnet *, 134 const struct in6_addr *, u_long *, int *); 135 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int); 136 137 #ifdef RFC2292 138 static int ip6_pcbopts(struct ip6_pktopts **, struct socket *, struct sockopt *); 139 #endif 140 141 /* 142 * IP6 output. The packet in mbuf chain m contains a skeletal IP6 143 * header (with pri, len, nxt, hlim, src, dst). 144 * This function may modify ver and hlim only. 145 * The mbuf chain containing the packet will be freed. 146 * The mbuf opt, if present, will not be freed. 147 * 148 * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and 149 * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one, 150 * which is rt_rmx.rmx_mtu. 151 */ 152 int 153 ip6_output( 154 struct mbuf *m0, 155 struct ip6_pktopts *opt, 156 struct route *ro, 157 int flags, 158 struct ip6_moptions *im6o, 159 struct socket *so, 160 struct ifnet **ifpp /* XXX: just for statistics */ 161 ) 162 { 163 struct ip6_hdr *ip6, *mhip6; 164 struct ifnet *ifp, *origifp; 165 struct mbuf *m = m0; 166 int hlen, tlen, len, off; 167 bool tso; 168 struct route ip6route; 169 struct rtentry *rt = NULL; 170 const struct sockaddr_in6 *dst; 171 struct sockaddr_in6 src_sa, dst_sa; 172 int error = 0; 173 struct in6_ifaddr *ia = NULL; 174 u_long mtu; 175 int alwaysfrag, dontfrag; 176 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; 177 struct ip6_exthdrs exthdrs; 178 struct in6_addr finaldst, src0, dst0; 179 u_int32_t zone; 180 struct route *ro_pmtu = NULL; 181 int hdrsplit = 0; 182 int needipsec = 0; 183 #ifdef IPSEC 184 struct secpolicy *sp = NULL; 185 #endif 186 187 memset(&ip6route, 0, sizeof(ip6route)); 188 189 #ifdef DIAGNOSTIC 190 if ((m->m_flags & M_PKTHDR) == 0) 191 panic("ip6_output: no HDR"); 192 193 if ((m->m_pkthdr.csum_flags & 194 (M_CSUM_TCPv4|M_CSUM_UDPv4|M_CSUM_TSOv4)) != 0) { 195 panic("ip6_output: IPv4 checksum offload flags: %d", 196 m->m_pkthdr.csum_flags); 197 } 198 199 if ((m->m_pkthdr.csum_flags & (M_CSUM_TCPv6|M_CSUM_UDPv6)) == 200 (M_CSUM_TCPv6|M_CSUM_UDPv6)) { 201 panic("ip6_output: conflicting checksum offload flags: %d", 202 m->m_pkthdr.csum_flags); 203 } 204 #endif 205 206 M_CSUM_DATA_IPv6_HL_SET(m->m_pkthdr.csum_data, sizeof(struct ip6_hdr)); 207 208 #define MAKE_EXTHDR(hp, mp) \ 209 do { \ 210 if (hp) { \ 211 struct ip6_ext *eh = (struct ip6_ext *)(hp); \ 212 error = ip6_copyexthdr((mp), (void *)(hp), \ 213 ((eh)->ip6e_len + 1) << 3); \ 214 if (error) \ 215 goto freehdrs; \ 216 } \ 217 } while (/*CONSTCOND*/ 0) 218 219 memset(&exthdrs, 0, sizeof(exthdrs)); 220 if (opt) { 221 /* Hop-by-Hop options header */ 222 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh); 223 /* Destination options header(1st part) */ 224 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1); 225 /* Routing header */ 226 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr); 227 /* Destination options header(2nd part) */ 228 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2); 229 } 230 231 /* 232 * Calculate the total length of the extension header chain. 233 * Keep the length of the unfragmentable part for fragmentation. 234 */ 235 optlen = 0; 236 if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len; 237 if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len; 238 if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len; 239 unfragpartlen = optlen + sizeof(struct ip6_hdr); 240 /* NOTE: we don't add AH/ESP length here. do that later. */ 241 if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len; 242 243 #ifdef IPSEC 244 if (ipsec_used) { 245 /* Check the security policy (SP) for the packet */ 246 247 sp = ipsec6_check_policy(m, so, flags, &needipsec, &error); 248 if (error != 0) { 249 /* 250 * Hack: -EINVAL is used to signal that a packet 251 * should be silently discarded. This is typically 252 * because we asked key management for an SA and 253 * it was delayed (e.g. kicked up to IKE). 254 */ 255 if (error == -EINVAL) 256 error = 0; 257 goto freehdrs; 258 } 259 } 260 #endif /* IPSEC */ 261 262 263 if (needipsec && 264 (m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0) { 265 in6_delayed_cksum(m); 266 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 267 } 268 269 270 /* 271 * If we need IPsec, or there is at least one extension header, 272 * separate IP6 header from the payload. 273 */ 274 if ((needipsec || optlen) && !hdrsplit) { 275 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 276 m = NULL; 277 goto freehdrs; 278 } 279 m = exthdrs.ip6e_ip6; 280 hdrsplit++; 281 } 282 283 /* adjust pointer */ 284 ip6 = mtod(m, struct ip6_hdr *); 285 286 /* adjust mbuf packet header length */ 287 m->m_pkthdr.len += optlen; 288 plen = m->m_pkthdr.len - sizeof(*ip6); 289 290 /* If this is a jumbo payload, insert a jumbo payload option. */ 291 if (plen > IPV6_MAXPACKET) { 292 if (!hdrsplit) { 293 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 294 m = NULL; 295 goto freehdrs; 296 } 297 m = exthdrs.ip6e_ip6; 298 hdrsplit++; 299 } 300 /* adjust pointer */ 301 ip6 = mtod(m, struct ip6_hdr *); 302 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) 303 goto freehdrs; 304 optlen += 8; /* XXX JUMBOOPTLEN */ 305 ip6->ip6_plen = 0; 306 } else 307 ip6->ip6_plen = htons(plen); 308 309 /* 310 * Concatenate headers and fill in next header fields. 311 * Here we have, on "m" 312 * IPv6 payload 313 * and we insert headers accordingly. Finally, we should be getting: 314 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 315 * 316 * during the header composing process, "m" points to IPv6 header. 317 * "mprev" points to an extension header prior to esp. 318 */ 319 { 320 u_char *nexthdrp = &ip6->ip6_nxt; 321 struct mbuf *mprev = m; 322 323 /* 324 * we treat dest2 specially. this makes IPsec processing 325 * much easier. the goal here is to make mprev point the 326 * mbuf prior to dest2. 327 * 328 * result: IPv6 dest2 payload 329 * m and mprev will point to IPv6 header. 330 */ 331 if (exthdrs.ip6e_dest2) { 332 if (!hdrsplit) 333 panic("assumption failed: hdr not split"); 334 exthdrs.ip6e_dest2->m_next = m->m_next; 335 m->m_next = exthdrs.ip6e_dest2; 336 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; 337 ip6->ip6_nxt = IPPROTO_DSTOPTS; 338 } 339 340 #define MAKE_CHAIN(m, mp, p, i)\ 341 do {\ 342 if (m) {\ 343 if (!hdrsplit) \ 344 panic("assumption failed: hdr not split"); \ 345 *mtod((m), u_char *) = *(p);\ 346 *(p) = (i);\ 347 p = mtod((m), u_char *);\ 348 (m)->m_next = (mp)->m_next;\ 349 (mp)->m_next = (m);\ 350 (mp) = (m);\ 351 }\ 352 } while (/*CONSTCOND*/ 0) 353 /* 354 * result: IPv6 hbh dest1 rthdr dest2 payload 355 * m will point to IPv6 header. mprev will point to the 356 * extension header prior to dest2 (rthdr in the above case). 357 */ 358 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); 359 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, 360 IPPROTO_DSTOPTS); 361 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, 362 IPPROTO_ROUTING); 363 364 M_CSUM_DATA_IPv6_HL_SET(m->m_pkthdr.csum_data, 365 sizeof(struct ip6_hdr) + optlen); 366 } 367 368 /* 369 * If there is a routing header, replace destination address field 370 * with the first hop of the routing header. 371 */ 372 if (exthdrs.ip6e_rthdr) { 373 struct ip6_rthdr *rh; 374 struct ip6_rthdr0 *rh0; 375 struct in6_addr *addr; 376 struct sockaddr_in6 sa; 377 378 rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr, 379 struct ip6_rthdr *)); 380 finaldst = ip6->ip6_dst; 381 switch (rh->ip6r_type) { 382 case IPV6_RTHDR_TYPE_0: 383 rh0 = (struct ip6_rthdr0 *)rh; 384 addr = (struct in6_addr *)(rh0 + 1); 385 386 /* 387 * construct a sockaddr_in6 form of 388 * the first hop. 389 * 390 * XXX: we may not have enough 391 * information about its scope zone; 392 * there is no standard API to pass 393 * the information from the 394 * application. 395 */ 396 sockaddr_in6_init(&sa, addr, 0, 0, 0); 397 if ((error = sa6_embedscope(&sa, 398 ip6_use_defzone)) != 0) { 399 goto bad; 400 } 401 ip6->ip6_dst = sa.sin6_addr; 402 (void)memmove(&addr[0], &addr[1], 403 sizeof(struct in6_addr) * 404 (rh0->ip6r0_segleft - 1)); 405 addr[rh0->ip6r0_segleft - 1] = finaldst; 406 /* XXX */ 407 in6_clearscope(addr + rh0->ip6r0_segleft - 1); 408 break; 409 default: /* is it possible? */ 410 error = EINVAL; 411 goto bad; 412 } 413 } 414 415 /* Source address validation */ 416 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && 417 (flags & IPV6_UNSPECSRC) == 0) { 418 error = EOPNOTSUPP; 419 IP6_STATINC(IP6_STAT_BADSCOPE); 420 goto bad; 421 } 422 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { 423 error = EOPNOTSUPP; 424 IP6_STATINC(IP6_STAT_BADSCOPE); 425 goto bad; 426 } 427 428 IP6_STATINC(IP6_STAT_LOCALOUT); 429 430 /* 431 * Route packet. 432 */ 433 /* initialize cached route */ 434 if (ro == NULL) { 435 ro = &ip6route; 436 } 437 ro_pmtu = ro; 438 if (opt && opt->ip6po_rthdr) 439 ro = &opt->ip6po_route; 440 441 /* 442 * if specified, try to fill in the traffic class field. 443 * do not override if a non-zero value is already set. 444 * we check the diffserv field and the ecn field separately. 445 */ 446 if (opt && opt->ip6po_tclass >= 0) { 447 int mask = 0; 448 449 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0) 450 mask |= 0xfc; 451 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0) 452 mask |= 0x03; 453 if (mask != 0) 454 ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20); 455 } 456 457 /* fill in or override the hop limit field, if necessary. */ 458 if (opt && opt->ip6po_hlim != -1) 459 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 460 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 461 if (im6o != NULL) 462 ip6->ip6_hlim = im6o->im6o_multicast_hlim; 463 else 464 ip6->ip6_hlim = ip6_defmcasthlim; 465 } 466 467 #ifdef IPSEC 468 if (needipsec) { 469 int s = splsoftnet(); 470 error = ipsec6_process_packet(m, sp->req); 471 472 /* 473 * Preserve KAME behaviour: ENOENT can be returned 474 * when an SA acquire is in progress. Don't propagate 475 * this to user-level; it confuses applications. 476 * XXX this will go away when the SADB is redone. 477 */ 478 if (error == ENOENT) 479 error = 0; 480 splx(s); 481 goto done; 482 } 483 #endif /* IPSEC */ 484 485 /* adjust pointer */ 486 ip6 = mtod(m, struct ip6_hdr *); 487 488 sockaddr_in6_init(&dst_sa, &ip6->ip6_dst, 0, 0, 0); 489 if ((error = in6_selectroute(&dst_sa, opt, im6o, ro, 490 &ifp, &rt, 0)) != 0) { 491 if (ifp != NULL) 492 in6_ifstat_inc(ifp, ifs6_out_discard); 493 goto bad; 494 } 495 if (rt == NULL) { 496 /* 497 * If in6_selectroute() does not return a route entry, 498 * dst may not have been updated. 499 */ 500 error = rtcache_setdst(ro, sin6tosa(&dst_sa)); 501 if (error) { 502 goto bad; 503 } 504 } 505 506 /* 507 * then rt (for unicast) and ifp must be non-NULL valid values. 508 */ 509 if ((flags & IPV6_FORWARDING) == 0) { 510 /* XXX: the FORWARDING flag can be set for mrouting. */ 511 in6_ifstat_inc(ifp, ifs6_out_request); 512 } 513 if (rt != NULL) { 514 ia = (struct in6_ifaddr *)(rt->rt_ifa); 515 rt->rt_use++; 516 } 517 518 /* 519 * The outgoing interface must be in the zone of source and 520 * destination addresses. We should use ia_ifp to support the 521 * case of sending packets to an address of our own. 522 */ 523 if (ia != NULL && ia->ia_ifp) 524 origifp = ia->ia_ifp; 525 else 526 origifp = ifp; 527 528 src0 = ip6->ip6_src; 529 if (in6_setscope(&src0, origifp, &zone)) 530 goto badscope; 531 sockaddr_in6_init(&src_sa, &ip6->ip6_src, 0, 0, 0); 532 if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id) 533 goto badscope; 534 535 dst0 = ip6->ip6_dst; 536 if (in6_setscope(&dst0, origifp, &zone)) 537 goto badscope; 538 /* re-initialize to be sure */ 539 sockaddr_in6_init(&dst_sa, &ip6->ip6_dst, 0, 0, 0); 540 if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) 541 goto badscope; 542 543 /* scope check is done. */ 544 545 if (rt == NULL || IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 546 dst = satocsin6(rtcache_getdst(ro)); 547 KASSERT(dst != NULL); 548 } else if (opt && rtcache_validate(&opt->ip6po_nextroute) != NULL) { 549 /* 550 * The nexthop is explicitly specified by the 551 * application. We assume the next hop is an IPv6 552 * address. 553 */ 554 dst = (struct sockaddr_in6 *)opt->ip6po_nexthop; 555 } else if ((rt->rt_flags & RTF_GATEWAY)) 556 dst = (struct sockaddr_in6 *)rt->rt_gateway; 557 else 558 dst = satocsin6(rtcache_getdst(ro)); 559 560 /* 561 * XXXXXX: original code follows: 562 */ 563 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 564 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ 565 else { 566 struct in6_multi *in6m; 567 568 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; 569 570 in6_ifstat_inc(ifp, ifs6_out_mcast); 571 572 /* 573 * Confirm that the outgoing interface supports multicast. 574 */ 575 if (!(ifp->if_flags & IFF_MULTICAST)) { 576 IP6_STATINC(IP6_STAT_NOROUTE); 577 in6_ifstat_inc(ifp, ifs6_out_discard); 578 error = ENETUNREACH; 579 goto bad; 580 } 581 582 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m); 583 if (in6m != NULL && 584 (im6o == NULL || im6o->im6o_multicast_loop)) { 585 /* 586 * If we belong to the destination multicast group 587 * on the outgoing interface, and the caller did not 588 * forbid loopback, loop back a copy. 589 */ 590 KASSERT(dst != NULL); 591 ip6_mloopback(ifp, m, dst); 592 } else { 593 /* 594 * If we are acting as a multicast router, perform 595 * multicast forwarding as if the packet had just 596 * arrived on the interface to which we are about 597 * to send. The multicast forwarding function 598 * recursively calls this function, using the 599 * IPV6_FORWARDING flag to prevent infinite recursion. 600 * 601 * Multicasts that are looped back by ip6_mloopback(), 602 * above, will be forwarded by the ip6_input() routine, 603 * if necessary. 604 */ 605 if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) { 606 if (ip6_mforward(ip6, ifp, m) != 0) { 607 m_freem(m); 608 goto done; 609 } 610 } 611 } 612 /* 613 * Multicasts with a hoplimit of zero may be looped back, 614 * above, but must not be transmitted on a network. 615 * Also, multicasts addressed to the loopback interface 616 * are not sent -- the above call to ip6_mloopback() will 617 * loop back a copy if this host actually belongs to the 618 * destination group on the loopback interface. 619 */ 620 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) || 621 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) { 622 m_freem(m); 623 goto done; 624 } 625 } 626 627 /* 628 * Fill the outgoing inteface to tell the upper layer 629 * to increment per-interface statistics. 630 */ 631 if (ifpp) 632 *ifpp = ifp; 633 634 /* Determine path MTU. */ 635 if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu, 636 &alwaysfrag)) != 0) 637 goto bad; 638 639 /* 640 * The caller of this function may specify to use the minimum MTU 641 * in some cases. 642 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU 643 * setting. The logic is a bit complicated; by default, unicast 644 * packets will follow path MTU while multicast packets will be sent at 645 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets 646 * including unicast ones will be sent at the minimum MTU. Multicast 647 * packets will always be sent at the minimum MTU unless 648 * IP6PO_MINMTU_DISABLE is explicitly specified. 649 * See RFC 3542 for more details. 650 */ 651 if (mtu > IPV6_MMTU) { 652 if ((flags & IPV6_MINMTU)) 653 mtu = IPV6_MMTU; 654 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL) 655 mtu = IPV6_MMTU; 656 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 657 (opt == NULL || 658 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) { 659 mtu = IPV6_MMTU; 660 } 661 } 662 663 /* 664 * clear embedded scope identifiers if necessary. 665 * in6_clearscope will touch the addresses only when necessary. 666 */ 667 in6_clearscope(&ip6->ip6_src); 668 in6_clearscope(&ip6->ip6_dst); 669 670 /* 671 * If the outgoing packet contains a hop-by-hop options header, 672 * it must be examined and processed even by the source node. 673 * (RFC 2460, section 4.) 674 */ 675 if (ip6->ip6_nxt == IPV6_HOPOPTS) { 676 u_int32_t dummy1; /* XXX unused */ 677 u_int32_t dummy2; /* XXX unused */ 678 int hoff = sizeof(struct ip6_hdr); 679 680 if (ip6_hopopts_input(&dummy1, &dummy2, &m, &hoff)) { 681 /* m was already freed at this point */ 682 error = EINVAL;/* better error? */ 683 goto done; 684 } 685 686 ip6 = mtod(m, struct ip6_hdr *); 687 } 688 689 /* 690 * Run through list of hooks for output packets. 691 */ 692 if ((error = pfil_run_hooks(inet6_pfil_hook, &m, ifp, PFIL_OUT)) != 0) 693 goto done; 694 if (m == NULL) 695 goto done; 696 ip6 = mtod(m, struct ip6_hdr *); 697 698 /* 699 * Send the packet to the outgoing interface. 700 * If necessary, do IPv6 fragmentation before sending. 701 * 702 * the logic here is rather complex: 703 * 1: normal case (dontfrag == 0, alwaysfrag == 0) 704 * 1-a: send as is if tlen <= path mtu 705 * 1-b: fragment if tlen > path mtu 706 * 707 * 2: if user asks us not to fragment (dontfrag == 1) 708 * 2-a: send as is if tlen <= interface mtu 709 * 2-b: error if tlen > interface mtu 710 * 711 * 3: if we always need to attach fragment header (alwaysfrag == 1) 712 * always fragment 713 * 714 * 4: if dontfrag == 1 && alwaysfrag == 1 715 * error, as we cannot handle this conflicting request 716 */ 717 tlen = m->m_pkthdr.len; 718 tso = (m->m_pkthdr.csum_flags & M_CSUM_TSOv6) != 0; 719 if (opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) 720 dontfrag = 1; 721 else 722 dontfrag = 0; 723 724 if (dontfrag && alwaysfrag) { /* case 4 */ 725 /* conflicting request - can't transmit */ 726 error = EMSGSIZE; 727 goto bad; 728 } 729 if (dontfrag && (!tso && tlen > IN6_LINKMTU(ifp))) { /* case 2-b */ 730 /* 731 * Even if the DONTFRAG option is specified, we cannot send the 732 * packet when the data length is larger than the MTU of the 733 * outgoing interface. 734 * Notify the error by sending IPV6_PATHMTU ancillary data as 735 * well as returning an error code (the latter is not described 736 * in the API spec.) 737 */ 738 u_int32_t mtu32; 739 struct ip6ctlparam ip6cp; 740 741 mtu32 = (u_int32_t)mtu; 742 memset(&ip6cp, 0, sizeof(ip6cp)); 743 ip6cp.ip6c_cmdarg = (void *)&mtu32; 744 pfctlinput2(PRC_MSGSIZE, 745 rtcache_getdst(ro_pmtu), &ip6cp); 746 747 error = EMSGSIZE; 748 goto bad; 749 } 750 751 /* 752 * transmit packet without fragmentation 753 */ 754 if (dontfrag || (!alwaysfrag && (tlen <= mtu || tso))) { 755 /* case 1-a and 2-a */ 756 struct in6_ifaddr *ia6; 757 int sw_csum; 758 759 ip6 = mtod(m, struct ip6_hdr *); 760 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 761 if (ia6) { 762 /* Record statistics for this interface address. */ 763 ia6->ia_ifa.ifa_data.ifad_outbytes += m->m_pkthdr.len; 764 } 765 766 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 767 if ((sw_csum & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0) { 768 if (IN6_NEED_CHECKSUM(ifp, 769 sw_csum & (M_CSUM_UDPv6|M_CSUM_TCPv6))) { 770 in6_delayed_cksum(m); 771 } 772 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 773 } 774 775 KASSERT(dst != NULL); 776 if (__predict_true(!tso || 777 (ifp->if_capenable & IFCAP_TSOv6) != 0)) { 778 error = nd6_output(ifp, origifp, m, dst, rt); 779 } else { 780 error = ip6_tso_output(ifp, origifp, m, dst, rt); 781 } 782 goto done; 783 } 784 785 if (tso) { 786 error = EINVAL; /* XXX */ 787 goto bad; 788 } 789 790 /* 791 * try to fragment the packet. case 1-b and 3 792 */ 793 if (mtu < IPV6_MMTU) { 794 /* path MTU cannot be less than IPV6_MMTU */ 795 error = EMSGSIZE; 796 in6_ifstat_inc(ifp, ifs6_out_fragfail); 797 goto bad; 798 } else if (ip6->ip6_plen == 0) { 799 /* jumbo payload cannot be fragmented */ 800 error = EMSGSIZE; 801 in6_ifstat_inc(ifp, ifs6_out_fragfail); 802 goto bad; 803 } else { 804 struct mbuf **mnext, *m_frgpart; 805 struct ip6_frag *ip6f; 806 u_int32_t id = htonl(ip6_randomid()); 807 u_char nextproto; 808 #if 0 /* see below */ 809 struct ip6ctlparam ip6cp; 810 u_int32_t mtu32; 811 #endif 812 813 /* 814 * Too large for the destination or interface; 815 * fragment if possible. 816 * Must be able to put at least 8 bytes per fragment. 817 */ 818 hlen = unfragpartlen; 819 if (mtu > IPV6_MAXPACKET) 820 mtu = IPV6_MAXPACKET; 821 822 #if 0 823 /* 824 * It is believed this code is a leftover from the 825 * development of the IPV6_RECVPATHMTU sockopt and 826 * associated work to implement RFC3542. 827 * It's not entirely clear what the intent of the API 828 * is at this point, so disable this code for now. 829 * The IPV6_RECVPATHMTU sockopt and/or IPV6_DONTFRAG 830 * will send notifications if the application requests. 831 */ 832 833 /* Notify a proper path MTU to applications. */ 834 mtu32 = (u_int32_t)mtu; 835 memset(&ip6cp, 0, sizeof(ip6cp)); 836 ip6cp.ip6c_cmdarg = (void *)&mtu32; 837 pfctlinput2(PRC_MSGSIZE, 838 rtcache_getdst(ro_pmtu), &ip6cp); 839 #endif 840 841 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; 842 if (len < 8) { 843 error = EMSGSIZE; 844 in6_ifstat_inc(ifp, ifs6_out_fragfail); 845 goto bad; 846 } 847 848 mnext = &m->m_nextpkt; 849 850 /* 851 * Change the next header field of the last header in the 852 * unfragmentable part. 853 */ 854 if (exthdrs.ip6e_rthdr) { 855 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); 856 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; 857 } else if (exthdrs.ip6e_dest1) { 858 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); 859 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; 860 } else if (exthdrs.ip6e_hbh) { 861 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); 862 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; 863 } else { 864 nextproto = ip6->ip6_nxt; 865 ip6->ip6_nxt = IPPROTO_FRAGMENT; 866 } 867 868 if ((m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) 869 != 0) { 870 if (IN6_NEED_CHECKSUM(ifp, 871 m->m_pkthdr.csum_flags & 872 (M_CSUM_UDPv6|M_CSUM_TCPv6))) { 873 in6_delayed_cksum(m); 874 } 875 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 876 } 877 878 /* 879 * Loop through length of segment after first fragment, 880 * make new header and copy data of each part and link onto 881 * chain. 882 */ 883 m0 = m; 884 for (off = hlen; off < tlen; off += len) { 885 struct mbuf *mlast; 886 887 MGETHDR(m, M_DONTWAIT, MT_HEADER); 888 if (!m) { 889 error = ENOBUFS; 890 IP6_STATINC(IP6_STAT_ODROPPED); 891 goto sendorfree; 892 } 893 m->m_pkthdr.rcvif = NULL; 894 m->m_flags = m0->m_flags & M_COPYFLAGS; 895 *mnext = m; 896 mnext = &m->m_nextpkt; 897 m->m_data += max_linkhdr; 898 mhip6 = mtod(m, struct ip6_hdr *); 899 *mhip6 = *ip6; 900 m->m_len = sizeof(*mhip6); 901 /* 902 * ip6f must be valid if error is 0. But how 903 * can a compiler be expected to infer this? 904 */ 905 ip6f = NULL; 906 error = ip6_insertfraghdr(m0, m, hlen, &ip6f); 907 if (error) { 908 IP6_STATINC(IP6_STAT_ODROPPED); 909 goto sendorfree; 910 } 911 ip6f->ip6f_offlg = htons((u_int16_t)((off - hlen) & ~7)); 912 if (off + len >= tlen) 913 len = tlen - off; 914 else 915 ip6f->ip6f_offlg |= IP6F_MORE_FRAG; 916 mhip6->ip6_plen = htons((u_int16_t)(len + hlen + 917 sizeof(*ip6f) - sizeof(struct ip6_hdr))); 918 if ((m_frgpart = m_copy(m0, off, len)) == 0) { 919 error = ENOBUFS; 920 IP6_STATINC(IP6_STAT_ODROPPED); 921 goto sendorfree; 922 } 923 for (mlast = m; mlast->m_next; mlast = mlast->m_next) 924 ; 925 mlast->m_next = m_frgpart; 926 m->m_pkthdr.len = len + hlen + sizeof(*ip6f); 927 m->m_pkthdr.rcvif = NULL; 928 ip6f->ip6f_reserved = 0; 929 ip6f->ip6f_ident = id; 930 ip6f->ip6f_nxt = nextproto; 931 IP6_STATINC(IP6_STAT_OFRAGMENTS); 932 in6_ifstat_inc(ifp, ifs6_out_fragcreat); 933 } 934 935 in6_ifstat_inc(ifp, ifs6_out_fragok); 936 } 937 938 /* 939 * Remove leading garbages. 940 */ 941 sendorfree: 942 m = m0->m_nextpkt; 943 m0->m_nextpkt = 0; 944 m_freem(m0); 945 for (m0 = m; m; m = m0) { 946 m0 = m->m_nextpkt; 947 m->m_nextpkt = 0; 948 if (error == 0) { 949 struct in6_ifaddr *ia6; 950 ip6 = mtod(m, struct ip6_hdr *); 951 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 952 if (ia6) { 953 /* 954 * Record statistics for this interface 955 * address. 956 */ 957 ia6->ia_ifa.ifa_data.ifad_outbytes += 958 m->m_pkthdr.len; 959 } 960 KASSERT(dst != NULL); 961 error = nd6_output(ifp, origifp, m, dst, rt); 962 } else 963 m_freem(m); 964 } 965 966 if (error == 0) 967 IP6_STATINC(IP6_STAT_FRAGMENTED); 968 969 done: 970 rtcache_free(&ip6route); 971 972 #ifdef IPSEC 973 if (sp != NULL) 974 KEY_FREESP(&sp); 975 #endif /* IPSEC */ 976 977 978 return (error); 979 980 freehdrs: 981 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */ 982 m_freem(exthdrs.ip6e_dest1); 983 m_freem(exthdrs.ip6e_rthdr); 984 m_freem(exthdrs.ip6e_dest2); 985 /* FALLTHROUGH */ 986 bad: 987 m_freem(m); 988 goto done; 989 badscope: 990 IP6_STATINC(IP6_STAT_BADSCOPE); 991 in6_ifstat_inc(origifp, ifs6_out_discard); 992 if (error == 0) 993 error = EHOSTUNREACH; /* XXX */ 994 goto bad; 995 } 996 997 static int 998 ip6_copyexthdr(struct mbuf **mp, void *hdr, int hlen) 999 { 1000 struct mbuf *m; 1001 1002 if (hlen > MCLBYTES) 1003 return (ENOBUFS); /* XXX */ 1004 1005 MGET(m, M_DONTWAIT, MT_DATA); 1006 if (!m) 1007 return (ENOBUFS); 1008 1009 if (hlen > MLEN) { 1010 MCLGET(m, M_DONTWAIT); 1011 if ((m->m_flags & M_EXT) == 0) { 1012 m_free(m); 1013 return (ENOBUFS); 1014 } 1015 } 1016 m->m_len = hlen; 1017 if (hdr) 1018 bcopy(hdr, mtod(m, void *), hlen); 1019 1020 *mp = m; 1021 return (0); 1022 } 1023 1024 /* 1025 * Process a delayed payload checksum calculation. 1026 */ 1027 void 1028 in6_delayed_cksum(struct mbuf *m) 1029 { 1030 uint16_t csum, offset; 1031 1032 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0); 1033 KASSERT((~m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0); 1034 KASSERT((m->m_pkthdr.csum_flags 1035 & (M_CSUM_UDPv4|M_CSUM_TCPv4|M_CSUM_TSOv4)) == 0); 1036 1037 offset = M_CSUM_DATA_IPv6_HL(m->m_pkthdr.csum_data); 1038 csum = in6_cksum(m, 0, offset, m->m_pkthdr.len - offset); 1039 if (csum == 0 && (m->m_pkthdr.csum_flags & M_CSUM_UDPv6) != 0) { 1040 csum = 0xffff; 1041 } 1042 1043 offset += M_CSUM_DATA_IPv6_OFFSET(m->m_pkthdr.csum_data); 1044 if ((offset + sizeof(csum)) > m->m_len) { 1045 m_copyback(m, offset, sizeof(csum), &csum); 1046 } else { 1047 *(uint16_t *)(mtod(m, char *) + offset) = csum; 1048 } 1049 } 1050 1051 /* 1052 * Insert jumbo payload option. 1053 */ 1054 static int 1055 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen) 1056 { 1057 struct mbuf *mopt; 1058 u_int8_t *optbuf; 1059 u_int32_t v; 1060 1061 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */ 1062 1063 /* 1064 * If there is no hop-by-hop options header, allocate new one. 1065 * If there is one but it doesn't have enough space to store the 1066 * jumbo payload option, allocate a cluster to store the whole options. 1067 * Otherwise, use it to store the options. 1068 */ 1069 if (exthdrs->ip6e_hbh == 0) { 1070 MGET(mopt, M_DONTWAIT, MT_DATA); 1071 if (mopt == 0) 1072 return (ENOBUFS); 1073 mopt->m_len = JUMBOOPTLEN; 1074 optbuf = mtod(mopt, u_int8_t *); 1075 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */ 1076 exthdrs->ip6e_hbh = mopt; 1077 } else { 1078 struct ip6_hbh *hbh; 1079 1080 mopt = exthdrs->ip6e_hbh; 1081 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) { 1082 /* 1083 * XXX assumption: 1084 * - exthdrs->ip6e_hbh is not referenced from places 1085 * other than exthdrs. 1086 * - exthdrs->ip6e_hbh is not an mbuf chain. 1087 */ 1088 int oldoptlen = mopt->m_len; 1089 struct mbuf *n; 1090 1091 /* 1092 * XXX: give up if the whole (new) hbh header does 1093 * not fit even in an mbuf cluster. 1094 */ 1095 if (oldoptlen + JUMBOOPTLEN > MCLBYTES) 1096 return (ENOBUFS); 1097 1098 /* 1099 * As a consequence, we must always prepare a cluster 1100 * at this point. 1101 */ 1102 MGET(n, M_DONTWAIT, MT_DATA); 1103 if (n) { 1104 MCLGET(n, M_DONTWAIT); 1105 if ((n->m_flags & M_EXT) == 0) { 1106 m_freem(n); 1107 n = NULL; 1108 } 1109 } 1110 if (!n) 1111 return (ENOBUFS); 1112 n->m_len = oldoptlen + JUMBOOPTLEN; 1113 bcopy(mtod(mopt, void *), mtod(n, void *), 1114 oldoptlen); 1115 optbuf = mtod(n, u_int8_t *) + oldoptlen; 1116 m_freem(mopt); 1117 mopt = exthdrs->ip6e_hbh = n; 1118 } else { 1119 optbuf = mtod(mopt, u_int8_t *) + mopt->m_len; 1120 mopt->m_len += JUMBOOPTLEN; 1121 } 1122 optbuf[0] = IP6OPT_PADN; 1123 optbuf[1] = 0; 1124 1125 /* 1126 * Adjust the header length according to the pad and 1127 * the jumbo payload option. 1128 */ 1129 hbh = mtod(mopt, struct ip6_hbh *); 1130 hbh->ip6h_len += (JUMBOOPTLEN >> 3); 1131 } 1132 1133 /* fill in the option. */ 1134 optbuf[2] = IP6OPT_JUMBO; 1135 optbuf[3] = 4; 1136 v = (u_int32_t)htonl(plen + JUMBOOPTLEN); 1137 bcopy(&v, &optbuf[4], sizeof(u_int32_t)); 1138 1139 /* finally, adjust the packet header length */ 1140 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN; 1141 1142 return (0); 1143 #undef JUMBOOPTLEN 1144 } 1145 1146 /* 1147 * Insert fragment header and copy unfragmentable header portions. 1148 * 1149 * *frghdrp will not be read, and it is guaranteed that either an 1150 * error is returned or that *frghdrp will point to space allocated 1151 * for the fragment header. 1152 */ 1153 static int 1154 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen, 1155 struct ip6_frag **frghdrp) 1156 { 1157 struct mbuf *n, *mlast; 1158 1159 if (hlen > sizeof(struct ip6_hdr)) { 1160 n = m_copym(m0, sizeof(struct ip6_hdr), 1161 hlen - sizeof(struct ip6_hdr), M_DONTWAIT); 1162 if (n == 0) 1163 return (ENOBUFS); 1164 m->m_next = n; 1165 } else 1166 n = m; 1167 1168 /* Search for the last mbuf of unfragmentable part. */ 1169 for (mlast = n; mlast->m_next; mlast = mlast->m_next) 1170 ; 1171 1172 if ((mlast->m_flags & M_EXT) == 0 && 1173 M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) { 1174 /* use the trailing space of the last mbuf for the fragment hdr */ 1175 *frghdrp = (struct ip6_frag *)(mtod(mlast, char *) + 1176 mlast->m_len); 1177 mlast->m_len += sizeof(struct ip6_frag); 1178 m->m_pkthdr.len += sizeof(struct ip6_frag); 1179 } else { 1180 /* allocate a new mbuf for the fragment header */ 1181 struct mbuf *mfrg; 1182 1183 MGET(mfrg, M_DONTWAIT, MT_DATA); 1184 if (mfrg == 0) 1185 return (ENOBUFS); 1186 mfrg->m_len = sizeof(struct ip6_frag); 1187 *frghdrp = mtod(mfrg, struct ip6_frag *); 1188 mlast->m_next = mfrg; 1189 } 1190 1191 return (0); 1192 } 1193 1194 static int 1195 ip6_getpmtu(struct route *ro_pmtu, struct route *ro, struct ifnet *ifp, 1196 const struct in6_addr *dst, u_long *mtup, int *alwaysfragp) 1197 { 1198 struct rtentry *rt; 1199 u_int32_t mtu = 0; 1200 int alwaysfrag = 0; 1201 int error = 0; 1202 1203 if (ro_pmtu != ro) { 1204 union { 1205 struct sockaddr dst; 1206 struct sockaddr_in6 dst6; 1207 } u; 1208 1209 /* The first hop and the final destination may differ. */ 1210 sockaddr_in6_init(&u.dst6, dst, 0, 0, 0); 1211 rt = rtcache_lookup(ro_pmtu, &u.dst); 1212 } else 1213 rt = rtcache_validate(ro_pmtu); 1214 if (rt != NULL) { 1215 u_int32_t ifmtu; 1216 1217 if (ifp == NULL) 1218 ifp = rt->rt_ifp; 1219 ifmtu = IN6_LINKMTU(ifp); 1220 mtu = rt->rt_rmx.rmx_mtu; 1221 if (mtu == 0) 1222 mtu = ifmtu; 1223 else if (mtu < IPV6_MMTU) { 1224 /* 1225 * RFC2460 section 5, last paragraph: 1226 * if we record ICMPv6 too big message with 1227 * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU 1228 * or smaller, with fragment header attached. 1229 * (fragment header is needed regardless from the 1230 * packet size, for translators to identify packets) 1231 */ 1232 alwaysfrag = 1; 1233 mtu = IPV6_MMTU; 1234 } else if (mtu > ifmtu) { 1235 /* 1236 * The MTU on the route is larger than the MTU on 1237 * the interface! This shouldn't happen, unless the 1238 * MTU of the interface has been changed after the 1239 * interface was brought up. Change the MTU in the 1240 * route to match the interface MTU (as long as the 1241 * field isn't locked). 1242 */ 1243 mtu = ifmtu; 1244 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 1245 rt->rt_rmx.rmx_mtu = mtu; 1246 } 1247 } else if (ifp) { 1248 mtu = IN6_LINKMTU(ifp); 1249 } else 1250 error = EHOSTUNREACH; /* XXX */ 1251 1252 *mtup = mtu; 1253 if (alwaysfragp) 1254 *alwaysfragp = alwaysfrag; 1255 return (error); 1256 } 1257 1258 /* 1259 * IP6 socket option processing. 1260 */ 1261 int 1262 ip6_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1263 { 1264 int optdatalen, uproto; 1265 void *optdata; 1266 struct in6pcb *in6p = sotoin6pcb(so); 1267 struct ip_moptions **mopts; 1268 int error, optval; 1269 int level, optname; 1270 1271 KASSERT(sopt != NULL); 1272 1273 level = sopt->sopt_level; 1274 optname = sopt->sopt_name; 1275 1276 error = optval = 0; 1277 uproto = (int)so->so_proto->pr_protocol; 1278 1279 switch (level) { 1280 case IPPROTO_IP: 1281 switch (optname) { 1282 case IP_ADD_MEMBERSHIP: 1283 case IP_DROP_MEMBERSHIP: 1284 case IP_MULTICAST_IF: 1285 case IP_MULTICAST_LOOP: 1286 case IP_MULTICAST_TTL: 1287 mopts = &in6p->in6p_v4moptions; 1288 switch (op) { 1289 case PRCO_GETOPT: 1290 return ip_getmoptions(*mopts, sopt); 1291 case PRCO_SETOPT: 1292 return ip_setmoptions(mopts, sopt); 1293 default: 1294 return EINVAL; 1295 } 1296 default: 1297 return ENOPROTOOPT; 1298 } 1299 case IPPROTO_IPV6: 1300 break; 1301 default: 1302 return ENOPROTOOPT; 1303 } 1304 switch (op) { 1305 case PRCO_SETOPT: 1306 switch (optname) { 1307 #ifdef RFC2292 1308 case IPV6_2292PKTOPTIONS: 1309 error = ip6_pcbopts(&in6p->in6p_outputopts, so, sopt); 1310 break; 1311 #endif 1312 1313 /* 1314 * Use of some Hop-by-Hop options or some 1315 * Destination options, might require special 1316 * privilege. That is, normal applications 1317 * (without special privilege) might be forbidden 1318 * from setting certain options in outgoing packets, 1319 * and might never see certain options in received 1320 * packets. [RFC 2292 Section 6] 1321 * KAME specific note: 1322 * KAME prevents non-privileged users from sending or 1323 * receiving ANY hbh/dst options in order to avoid 1324 * overhead of parsing options in the kernel. 1325 */ 1326 case IPV6_RECVHOPOPTS: 1327 case IPV6_RECVDSTOPTS: 1328 case IPV6_RECVRTHDRDSTOPTS: 1329 error = kauth_authorize_network(kauth_cred_get(), 1330 KAUTH_NETWORK_IPV6, KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, 1331 NULL, NULL, NULL); 1332 if (error) 1333 break; 1334 /* FALLTHROUGH */ 1335 case IPV6_UNICAST_HOPS: 1336 case IPV6_HOPLIMIT: 1337 case IPV6_FAITH: 1338 1339 case IPV6_RECVPKTINFO: 1340 case IPV6_RECVHOPLIMIT: 1341 case IPV6_RECVRTHDR: 1342 case IPV6_RECVPATHMTU: 1343 case IPV6_RECVTCLASS: 1344 case IPV6_V6ONLY: 1345 error = sockopt_getint(sopt, &optval); 1346 if (error) 1347 break; 1348 switch (optname) { 1349 case IPV6_UNICAST_HOPS: 1350 if (optval < -1 || optval >= 256) 1351 error = EINVAL; 1352 else { 1353 /* -1 = kernel default */ 1354 in6p->in6p_hops = optval; 1355 } 1356 break; 1357 #define OPTSET(bit) \ 1358 do { \ 1359 if (optval) \ 1360 in6p->in6p_flags |= (bit); \ 1361 else \ 1362 in6p->in6p_flags &= ~(bit); \ 1363 } while (/*CONSTCOND*/ 0) 1364 1365 #ifdef RFC2292 1366 #define OPTSET2292(bit) \ 1367 do { \ 1368 in6p->in6p_flags |= IN6P_RFC2292; \ 1369 if (optval) \ 1370 in6p->in6p_flags |= (bit); \ 1371 else \ 1372 in6p->in6p_flags &= ~(bit); \ 1373 } while (/*CONSTCOND*/ 0) 1374 #endif 1375 1376 #define OPTBIT(bit) (in6p->in6p_flags & (bit) ? 1 : 0) 1377 1378 case IPV6_RECVPKTINFO: 1379 #ifdef RFC2292 1380 /* cannot mix with RFC2292 */ 1381 if (OPTBIT(IN6P_RFC2292)) { 1382 error = EINVAL; 1383 break; 1384 } 1385 #endif 1386 OPTSET(IN6P_PKTINFO); 1387 break; 1388 1389 case IPV6_HOPLIMIT: 1390 { 1391 struct ip6_pktopts **optp; 1392 1393 #ifdef RFC2292 1394 /* cannot mix with RFC2292 */ 1395 if (OPTBIT(IN6P_RFC2292)) { 1396 error = EINVAL; 1397 break; 1398 } 1399 #endif 1400 optp = &in6p->in6p_outputopts; 1401 error = ip6_pcbopt(IPV6_HOPLIMIT, 1402 (u_char *)&optval, 1403 sizeof(optval), 1404 optp, 1405 kauth_cred_get(), uproto); 1406 break; 1407 } 1408 1409 case IPV6_RECVHOPLIMIT: 1410 #ifdef RFC2292 1411 /* cannot mix with RFC2292 */ 1412 if (OPTBIT(IN6P_RFC2292)) { 1413 error = EINVAL; 1414 break; 1415 } 1416 #endif 1417 OPTSET(IN6P_HOPLIMIT); 1418 break; 1419 1420 case IPV6_RECVHOPOPTS: 1421 #ifdef RFC2292 1422 /* cannot mix with RFC2292 */ 1423 if (OPTBIT(IN6P_RFC2292)) { 1424 error = EINVAL; 1425 break; 1426 } 1427 #endif 1428 OPTSET(IN6P_HOPOPTS); 1429 break; 1430 1431 case IPV6_RECVDSTOPTS: 1432 #ifdef RFC2292 1433 /* cannot mix with RFC2292 */ 1434 if (OPTBIT(IN6P_RFC2292)) { 1435 error = EINVAL; 1436 break; 1437 } 1438 #endif 1439 OPTSET(IN6P_DSTOPTS); 1440 break; 1441 1442 case IPV6_RECVRTHDRDSTOPTS: 1443 #ifdef RFC2292 1444 /* cannot mix with RFC2292 */ 1445 if (OPTBIT(IN6P_RFC2292)) { 1446 error = EINVAL; 1447 break; 1448 } 1449 #endif 1450 OPTSET(IN6P_RTHDRDSTOPTS); 1451 break; 1452 1453 case IPV6_RECVRTHDR: 1454 #ifdef RFC2292 1455 /* cannot mix with RFC2292 */ 1456 if (OPTBIT(IN6P_RFC2292)) { 1457 error = EINVAL; 1458 break; 1459 } 1460 #endif 1461 OPTSET(IN6P_RTHDR); 1462 break; 1463 1464 case IPV6_FAITH: 1465 OPTSET(IN6P_FAITH); 1466 break; 1467 1468 case IPV6_RECVPATHMTU: 1469 /* 1470 * We ignore this option for TCP 1471 * sockets. 1472 * (RFC3542 leaves this case 1473 * unspecified.) 1474 */ 1475 if (uproto != IPPROTO_TCP) 1476 OPTSET(IN6P_MTU); 1477 break; 1478 1479 case IPV6_V6ONLY: 1480 /* 1481 * make setsockopt(IPV6_V6ONLY) 1482 * available only prior to bind(2). 1483 * see ipng mailing list, Jun 22 2001. 1484 */ 1485 if (in6p->in6p_lport || 1486 !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) { 1487 error = EINVAL; 1488 break; 1489 } 1490 #ifdef INET6_BINDV6ONLY 1491 if (!optval) 1492 error = EINVAL; 1493 #else 1494 OPTSET(IN6P_IPV6_V6ONLY); 1495 #endif 1496 break; 1497 case IPV6_RECVTCLASS: 1498 #ifdef RFC2292 1499 /* cannot mix with RFC2292 XXX */ 1500 if (OPTBIT(IN6P_RFC2292)) { 1501 error = EINVAL; 1502 break; 1503 } 1504 #endif 1505 OPTSET(IN6P_TCLASS); 1506 break; 1507 1508 } 1509 break; 1510 1511 case IPV6_OTCLASS: 1512 { 1513 struct ip6_pktopts **optp; 1514 u_int8_t tclass; 1515 1516 error = sockopt_get(sopt, &tclass, sizeof(tclass)); 1517 if (error) 1518 break; 1519 optp = &in6p->in6p_outputopts; 1520 error = ip6_pcbopt(optname, 1521 (u_char *)&tclass, 1522 sizeof(tclass), 1523 optp, 1524 kauth_cred_get(), uproto); 1525 break; 1526 } 1527 1528 case IPV6_TCLASS: 1529 case IPV6_DONTFRAG: 1530 case IPV6_USE_MIN_MTU: 1531 case IPV6_PREFER_TEMPADDR: 1532 error = sockopt_getint(sopt, &optval); 1533 if (error) 1534 break; 1535 { 1536 struct ip6_pktopts **optp; 1537 optp = &in6p->in6p_outputopts; 1538 error = ip6_pcbopt(optname, 1539 (u_char *)&optval, 1540 sizeof(optval), 1541 optp, 1542 kauth_cred_get(), uproto); 1543 break; 1544 } 1545 1546 #ifdef RFC2292 1547 case IPV6_2292PKTINFO: 1548 case IPV6_2292HOPLIMIT: 1549 case IPV6_2292HOPOPTS: 1550 case IPV6_2292DSTOPTS: 1551 case IPV6_2292RTHDR: 1552 /* RFC 2292 */ 1553 error = sockopt_getint(sopt, &optval); 1554 if (error) 1555 break; 1556 1557 switch (optname) { 1558 case IPV6_2292PKTINFO: 1559 OPTSET2292(IN6P_PKTINFO); 1560 break; 1561 case IPV6_2292HOPLIMIT: 1562 OPTSET2292(IN6P_HOPLIMIT); 1563 break; 1564 case IPV6_2292HOPOPTS: 1565 /* 1566 * Check super-user privilege. 1567 * See comments for IPV6_RECVHOPOPTS. 1568 */ 1569 error = 1570 kauth_authorize_network(kauth_cred_get(), 1571 KAUTH_NETWORK_IPV6, 1572 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, 1573 NULL, NULL); 1574 if (error) 1575 return (error); 1576 OPTSET2292(IN6P_HOPOPTS); 1577 break; 1578 case IPV6_2292DSTOPTS: 1579 error = 1580 kauth_authorize_network(kauth_cred_get(), 1581 KAUTH_NETWORK_IPV6, 1582 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, 1583 NULL, NULL); 1584 if (error) 1585 return (error); 1586 OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */ 1587 break; 1588 case IPV6_2292RTHDR: 1589 OPTSET2292(IN6P_RTHDR); 1590 break; 1591 } 1592 break; 1593 #endif 1594 case IPV6_PKTINFO: 1595 case IPV6_HOPOPTS: 1596 case IPV6_RTHDR: 1597 case IPV6_DSTOPTS: 1598 case IPV6_RTHDRDSTOPTS: 1599 case IPV6_NEXTHOP: { 1600 /* new advanced API (RFC3542) */ 1601 void *optbuf; 1602 int optbuflen; 1603 struct ip6_pktopts **optp; 1604 1605 #ifdef RFC2292 1606 /* cannot mix with RFC2292 */ 1607 if (OPTBIT(IN6P_RFC2292)) { 1608 error = EINVAL; 1609 break; 1610 } 1611 #endif 1612 1613 optbuflen = sopt->sopt_size; 1614 optbuf = malloc(optbuflen, M_IP6OPT, M_NOWAIT); 1615 if (optbuf == NULL) { 1616 error = ENOBUFS; 1617 break; 1618 } 1619 1620 error = sockopt_get(sopt, optbuf, optbuflen); 1621 if (error) { 1622 free(optbuf, M_IP6OPT); 1623 break; 1624 } 1625 optp = &in6p->in6p_outputopts; 1626 error = ip6_pcbopt(optname, optbuf, optbuflen, 1627 optp, kauth_cred_get(), uproto); 1628 1629 free(optbuf, M_IP6OPT); 1630 break; 1631 } 1632 #undef OPTSET 1633 1634 case IPV6_MULTICAST_IF: 1635 case IPV6_MULTICAST_HOPS: 1636 case IPV6_MULTICAST_LOOP: 1637 case IPV6_JOIN_GROUP: 1638 case IPV6_LEAVE_GROUP: 1639 error = ip6_setmoptions(sopt, in6p); 1640 break; 1641 1642 case IPV6_PORTRANGE: 1643 error = sockopt_getint(sopt, &optval); 1644 if (error) 1645 break; 1646 1647 switch (optval) { 1648 case IPV6_PORTRANGE_DEFAULT: 1649 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1650 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1651 break; 1652 1653 case IPV6_PORTRANGE_HIGH: 1654 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1655 in6p->in6p_flags |= IN6P_HIGHPORT; 1656 break; 1657 1658 case IPV6_PORTRANGE_LOW: 1659 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1660 in6p->in6p_flags |= IN6P_LOWPORT; 1661 break; 1662 1663 default: 1664 error = EINVAL; 1665 break; 1666 } 1667 break; 1668 1669 case IPV6_PORTALGO: 1670 error = sockopt_getint(sopt, &optval); 1671 if (error) 1672 break; 1673 1674 error = portalgo_algo_index_select( 1675 (struct inpcb_hdr *)in6p, optval); 1676 break; 1677 1678 #if defined(IPSEC) 1679 case IPV6_IPSEC_POLICY: 1680 if (ipsec_enabled) { 1681 error = ipsec6_set_policy(in6p, optname, 1682 sopt->sopt_data, sopt->sopt_size, 1683 kauth_cred_get()); 1684 break; 1685 } 1686 /*FALLTHROUGH*/ 1687 #endif /* IPSEC */ 1688 1689 default: 1690 error = ENOPROTOOPT; 1691 break; 1692 } 1693 break; 1694 1695 case PRCO_GETOPT: 1696 switch (optname) { 1697 #ifdef RFC2292 1698 case IPV6_2292PKTOPTIONS: 1699 /* 1700 * RFC3542 (effectively) deprecated the 1701 * semantics of the 2292-style pktoptions. 1702 * Since it was not reliable in nature (i.e., 1703 * applications had to expect the lack of some 1704 * information after all), it would make sense 1705 * to simplify this part by always returning 1706 * empty data. 1707 */ 1708 break; 1709 #endif 1710 1711 case IPV6_RECVHOPOPTS: 1712 case IPV6_RECVDSTOPTS: 1713 case IPV6_RECVRTHDRDSTOPTS: 1714 case IPV6_UNICAST_HOPS: 1715 case IPV6_RECVPKTINFO: 1716 case IPV6_RECVHOPLIMIT: 1717 case IPV6_RECVRTHDR: 1718 case IPV6_RECVPATHMTU: 1719 1720 case IPV6_FAITH: 1721 case IPV6_V6ONLY: 1722 case IPV6_PORTRANGE: 1723 case IPV6_RECVTCLASS: 1724 switch (optname) { 1725 1726 case IPV6_RECVHOPOPTS: 1727 optval = OPTBIT(IN6P_HOPOPTS); 1728 break; 1729 1730 case IPV6_RECVDSTOPTS: 1731 optval = OPTBIT(IN6P_DSTOPTS); 1732 break; 1733 1734 case IPV6_RECVRTHDRDSTOPTS: 1735 optval = OPTBIT(IN6P_RTHDRDSTOPTS); 1736 break; 1737 1738 case IPV6_UNICAST_HOPS: 1739 optval = in6p->in6p_hops; 1740 break; 1741 1742 case IPV6_RECVPKTINFO: 1743 optval = OPTBIT(IN6P_PKTINFO); 1744 break; 1745 1746 case IPV6_RECVHOPLIMIT: 1747 optval = OPTBIT(IN6P_HOPLIMIT); 1748 break; 1749 1750 case IPV6_RECVRTHDR: 1751 optval = OPTBIT(IN6P_RTHDR); 1752 break; 1753 1754 case IPV6_RECVPATHMTU: 1755 optval = OPTBIT(IN6P_MTU); 1756 break; 1757 1758 case IPV6_FAITH: 1759 optval = OPTBIT(IN6P_FAITH); 1760 break; 1761 1762 case IPV6_V6ONLY: 1763 optval = OPTBIT(IN6P_IPV6_V6ONLY); 1764 break; 1765 1766 case IPV6_PORTRANGE: 1767 { 1768 int flags; 1769 flags = in6p->in6p_flags; 1770 if (flags & IN6P_HIGHPORT) 1771 optval = IPV6_PORTRANGE_HIGH; 1772 else if (flags & IN6P_LOWPORT) 1773 optval = IPV6_PORTRANGE_LOW; 1774 else 1775 optval = 0; 1776 break; 1777 } 1778 case IPV6_RECVTCLASS: 1779 optval = OPTBIT(IN6P_TCLASS); 1780 break; 1781 1782 } 1783 if (error) 1784 break; 1785 error = sockopt_setint(sopt, optval); 1786 break; 1787 1788 case IPV6_PATHMTU: 1789 { 1790 u_long pmtu = 0; 1791 struct ip6_mtuinfo mtuinfo; 1792 struct route *ro = &in6p->in6p_route; 1793 1794 if (!(so->so_state & SS_ISCONNECTED)) 1795 return (ENOTCONN); 1796 /* 1797 * XXX: we dot not consider the case of source 1798 * routing, or optional information to specify 1799 * the outgoing interface. 1800 */ 1801 error = ip6_getpmtu(ro, NULL, NULL, 1802 &in6p->in6p_faddr, &pmtu, NULL); 1803 if (error) 1804 break; 1805 if (pmtu > IPV6_MAXPACKET) 1806 pmtu = IPV6_MAXPACKET; 1807 1808 memset(&mtuinfo, 0, sizeof(mtuinfo)); 1809 mtuinfo.ip6m_mtu = (u_int32_t)pmtu; 1810 optdata = (void *)&mtuinfo; 1811 optdatalen = sizeof(mtuinfo); 1812 if (optdatalen > MCLBYTES) 1813 return (EMSGSIZE); /* XXX */ 1814 error = sockopt_set(sopt, optdata, optdatalen); 1815 break; 1816 } 1817 1818 #ifdef RFC2292 1819 case IPV6_2292PKTINFO: 1820 case IPV6_2292HOPLIMIT: 1821 case IPV6_2292HOPOPTS: 1822 case IPV6_2292RTHDR: 1823 case IPV6_2292DSTOPTS: 1824 switch (optname) { 1825 case IPV6_2292PKTINFO: 1826 optval = OPTBIT(IN6P_PKTINFO); 1827 break; 1828 case IPV6_2292HOPLIMIT: 1829 optval = OPTBIT(IN6P_HOPLIMIT); 1830 break; 1831 case IPV6_2292HOPOPTS: 1832 optval = OPTBIT(IN6P_HOPOPTS); 1833 break; 1834 case IPV6_2292RTHDR: 1835 optval = OPTBIT(IN6P_RTHDR); 1836 break; 1837 case IPV6_2292DSTOPTS: 1838 optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); 1839 break; 1840 } 1841 error = sockopt_setint(sopt, optval); 1842 break; 1843 #endif 1844 case IPV6_PKTINFO: 1845 case IPV6_HOPOPTS: 1846 case IPV6_RTHDR: 1847 case IPV6_DSTOPTS: 1848 case IPV6_RTHDRDSTOPTS: 1849 case IPV6_NEXTHOP: 1850 case IPV6_OTCLASS: 1851 case IPV6_TCLASS: 1852 case IPV6_DONTFRAG: 1853 case IPV6_USE_MIN_MTU: 1854 case IPV6_PREFER_TEMPADDR: 1855 error = ip6_getpcbopt(in6p->in6p_outputopts, 1856 optname, sopt); 1857 break; 1858 1859 case IPV6_MULTICAST_IF: 1860 case IPV6_MULTICAST_HOPS: 1861 case IPV6_MULTICAST_LOOP: 1862 case IPV6_JOIN_GROUP: 1863 case IPV6_LEAVE_GROUP: 1864 error = ip6_getmoptions(sopt, in6p); 1865 break; 1866 1867 case IPV6_PORTALGO: 1868 optval = ((struct inpcb_hdr *)in6p)->inph_portalgo; 1869 error = sockopt_setint(sopt, optval); 1870 break; 1871 1872 #if defined(IPSEC) 1873 case IPV6_IPSEC_POLICY: 1874 if (ipsec_used) { 1875 struct mbuf *m = NULL; 1876 1877 /* 1878 * XXX: this will return EINVAL as sopt is 1879 * empty 1880 */ 1881 error = ipsec6_get_policy(in6p, sopt->sopt_data, 1882 sopt->sopt_size, &m); 1883 if (!error) 1884 error = sockopt_setmbuf(sopt, m); 1885 break; 1886 } 1887 /*FALLTHROUGH*/ 1888 #endif /* IPSEC */ 1889 1890 default: 1891 error = ENOPROTOOPT; 1892 break; 1893 } 1894 break; 1895 } 1896 return (error); 1897 } 1898 1899 int 1900 ip6_raw_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1901 { 1902 int error = 0, optval; 1903 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); 1904 struct in6pcb *in6p = sotoin6pcb(so); 1905 int level, optname; 1906 1907 KASSERT(sopt != NULL); 1908 1909 level = sopt->sopt_level; 1910 optname = sopt->sopt_name; 1911 1912 if (level != IPPROTO_IPV6) { 1913 return ENOPROTOOPT; 1914 } 1915 1916 switch (optname) { 1917 case IPV6_CHECKSUM: 1918 /* 1919 * For ICMPv6 sockets, no modification allowed for checksum 1920 * offset, permit "no change" values to help existing apps. 1921 * 1922 * XXX RFC3542 says: "An attempt to set IPV6_CHECKSUM 1923 * for an ICMPv6 socket will fail." The current 1924 * behavior does not meet RFC3542. 1925 */ 1926 switch (op) { 1927 case PRCO_SETOPT: 1928 error = sockopt_getint(sopt, &optval); 1929 if (error) 1930 break; 1931 if ((optval % 2) != 0) { 1932 /* the API assumes even offset values */ 1933 error = EINVAL; 1934 } else if (so->so_proto->pr_protocol == 1935 IPPROTO_ICMPV6) { 1936 if (optval != icmp6off) 1937 error = EINVAL; 1938 } else 1939 in6p->in6p_cksum = optval; 1940 break; 1941 1942 case PRCO_GETOPT: 1943 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) 1944 optval = icmp6off; 1945 else 1946 optval = in6p->in6p_cksum; 1947 1948 error = sockopt_setint(sopt, optval); 1949 break; 1950 1951 default: 1952 error = EINVAL; 1953 break; 1954 } 1955 break; 1956 1957 default: 1958 error = ENOPROTOOPT; 1959 break; 1960 } 1961 1962 return (error); 1963 } 1964 1965 #ifdef RFC2292 1966 /* 1967 * Set up IP6 options in pcb for insertion in output packets or 1968 * specifying behavior of outgoing packets. 1969 */ 1970 static int 1971 ip6_pcbopts(struct ip6_pktopts **pktopt, struct socket *so, 1972 struct sockopt *sopt) 1973 { 1974 struct ip6_pktopts *opt = *pktopt; 1975 struct mbuf *m; 1976 int error = 0; 1977 1978 /* turn off any old options. */ 1979 if (opt) { 1980 #ifdef DIAGNOSTIC 1981 if (opt->ip6po_pktinfo || opt->ip6po_nexthop || 1982 opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 || 1983 opt->ip6po_rhinfo.ip6po_rhi_rthdr) 1984 printf("ip6_pcbopts: all specified options are cleared.\n"); 1985 #endif 1986 ip6_clearpktopts(opt, -1); 1987 } else { 1988 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT); 1989 if (opt == NULL) 1990 return (ENOBUFS); 1991 } 1992 *pktopt = NULL; 1993 1994 if (sopt == NULL || sopt->sopt_size == 0) { 1995 /* 1996 * Only turning off any previous options, regardless of 1997 * whether the opt is just created or given. 1998 */ 1999 free(opt, M_IP6OPT); 2000 return (0); 2001 } 2002 2003 /* set options specified by user. */ 2004 m = sockopt_getmbuf(sopt); 2005 if (m == NULL) { 2006 free(opt, M_IP6OPT); 2007 return (ENOBUFS); 2008 } 2009 2010 error = ip6_setpktopts(m, opt, NULL, kauth_cred_get(), 2011 so->so_proto->pr_protocol); 2012 m_freem(m); 2013 if (error != 0) { 2014 ip6_clearpktopts(opt, -1); /* XXX: discard all options */ 2015 free(opt, M_IP6OPT); 2016 return (error); 2017 } 2018 *pktopt = opt; 2019 return (0); 2020 } 2021 #endif 2022 2023 /* 2024 * initialize ip6_pktopts. beware that there are non-zero default values in 2025 * the struct. 2026 */ 2027 void 2028 ip6_initpktopts(struct ip6_pktopts *opt) 2029 { 2030 2031 memset(opt, 0, sizeof(*opt)); 2032 opt->ip6po_hlim = -1; /* -1 means default hop limit */ 2033 opt->ip6po_tclass = -1; /* -1 means default traffic class */ 2034 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY; 2035 opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM; 2036 } 2037 2038 #define sin6tosa(sin6) ((struct sockaddr *)(sin6)) /* XXX */ 2039 static int 2040 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt, 2041 kauth_cred_t cred, int uproto) 2042 { 2043 struct ip6_pktopts *opt; 2044 2045 if (*pktopt == NULL) { 2046 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT, 2047 M_NOWAIT); 2048 if (*pktopt == NULL) 2049 return (ENOBUFS); 2050 2051 ip6_initpktopts(*pktopt); 2052 } 2053 opt = *pktopt; 2054 2055 return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto)); 2056 } 2057 2058 static int 2059 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt) 2060 { 2061 void *optdata = NULL; 2062 int optdatalen = 0; 2063 struct ip6_ext *ip6e; 2064 int error = 0; 2065 struct in6_pktinfo null_pktinfo; 2066 int deftclass = 0, on; 2067 int defminmtu = IP6PO_MINMTU_MCASTONLY; 2068 int defpreftemp = IP6PO_TEMPADDR_SYSTEM; 2069 2070 switch (optname) { 2071 case IPV6_PKTINFO: 2072 if (pktopt && pktopt->ip6po_pktinfo) 2073 optdata = (void *)pktopt->ip6po_pktinfo; 2074 else { 2075 /* XXX: we don't have to do this every time... */ 2076 memset(&null_pktinfo, 0, sizeof(null_pktinfo)); 2077 optdata = (void *)&null_pktinfo; 2078 } 2079 optdatalen = sizeof(struct in6_pktinfo); 2080 break; 2081 case IPV6_OTCLASS: 2082 /* XXX */ 2083 return (EINVAL); 2084 case IPV6_TCLASS: 2085 if (pktopt && pktopt->ip6po_tclass >= 0) 2086 optdata = (void *)&pktopt->ip6po_tclass; 2087 else 2088 optdata = (void *)&deftclass; 2089 optdatalen = sizeof(int); 2090 break; 2091 case IPV6_HOPOPTS: 2092 if (pktopt && pktopt->ip6po_hbh) { 2093 optdata = (void *)pktopt->ip6po_hbh; 2094 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh; 2095 optdatalen = (ip6e->ip6e_len + 1) << 3; 2096 } 2097 break; 2098 case IPV6_RTHDR: 2099 if (pktopt && pktopt->ip6po_rthdr) { 2100 optdata = (void *)pktopt->ip6po_rthdr; 2101 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr; 2102 optdatalen = (ip6e->ip6e_len + 1) << 3; 2103 } 2104 break; 2105 case IPV6_RTHDRDSTOPTS: 2106 if (pktopt && pktopt->ip6po_dest1) { 2107 optdata = (void *)pktopt->ip6po_dest1; 2108 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1; 2109 optdatalen = (ip6e->ip6e_len + 1) << 3; 2110 } 2111 break; 2112 case IPV6_DSTOPTS: 2113 if (pktopt && pktopt->ip6po_dest2) { 2114 optdata = (void *)pktopt->ip6po_dest2; 2115 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2; 2116 optdatalen = (ip6e->ip6e_len + 1) << 3; 2117 } 2118 break; 2119 case IPV6_NEXTHOP: 2120 if (pktopt && pktopt->ip6po_nexthop) { 2121 optdata = (void *)pktopt->ip6po_nexthop; 2122 optdatalen = pktopt->ip6po_nexthop->sa_len; 2123 } 2124 break; 2125 case IPV6_USE_MIN_MTU: 2126 if (pktopt) 2127 optdata = (void *)&pktopt->ip6po_minmtu; 2128 else 2129 optdata = (void *)&defminmtu; 2130 optdatalen = sizeof(int); 2131 break; 2132 case IPV6_DONTFRAG: 2133 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG)) 2134 on = 1; 2135 else 2136 on = 0; 2137 optdata = (void *)&on; 2138 optdatalen = sizeof(on); 2139 break; 2140 case IPV6_PREFER_TEMPADDR: 2141 if (pktopt) 2142 optdata = (void *)&pktopt->ip6po_prefer_tempaddr; 2143 else 2144 optdata = (void *)&defpreftemp; 2145 optdatalen = sizeof(int); 2146 break; 2147 default: /* should not happen */ 2148 #ifdef DIAGNOSTIC 2149 panic("ip6_getpcbopt: unexpected option\n"); 2150 #endif 2151 return (ENOPROTOOPT); 2152 } 2153 2154 error = sockopt_set(sopt, optdata, optdatalen); 2155 2156 return (error); 2157 } 2158 2159 void 2160 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname) 2161 { 2162 if (optname == -1 || optname == IPV6_PKTINFO) { 2163 if (pktopt->ip6po_pktinfo) 2164 free(pktopt->ip6po_pktinfo, M_IP6OPT); 2165 pktopt->ip6po_pktinfo = NULL; 2166 } 2167 if (optname == -1 || optname == IPV6_HOPLIMIT) 2168 pktopt->ip6po_hlim = -1; 2169 if (optname == -1 || optname == IPV6_TCLASS) 2170 pktopt->ip6po_tclass = -1; 2171 if (optname == -1 || optname == IPV6_NEXTHOP) { 2172 rtcache_free(&pktopt->ip6po_nextroute); 2173 if (pktopt->ip6po_nexthop) 2174 free(pktopt->ip6po_nexthop, M_IP6OPT); 2175 pktopt->ip6po_nexthop = NULL; 2176 } 2177 if (optname == -1 || optname == IPV6_HOPOPTS) { 2178 if (pktopt->ip6po_hbh) 2179 free(pktopt->ip6po_hbh, M_IP6OPT); 2180 pktopt->ip6po_hbh = NULL; 2181 } 2182 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) { 2183 if (pktopt->ip6po_dest1) 2184 free(pktopt->ip6po_dest1, M_IP6OPT); 2185 pktopt->ip6po_dest1 = NULL; 2186 } 2187 if (optname == -1 || optname == IPV6_RTHDR) { 2188 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr) 2189 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT); 2190 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL; 2191 rtcache_free(&pktopt->ip6po_route); 2192 } 2193 if (optname == -1 || optname == IPV6_DSTOPTS) { 2194 if (pktopt->ip6po_dest2) 2195 free(pktopt->ip6po_dest2, M_IP6OPT); 2196 pktopt->ip6po_dest2 = NULL; 2197 } 2198 } 2199 2200 #define PKTOPT_EXTHDRCPY(type) \ 2201 do { \ 2202 if (src->type) { \ 2203 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\ 2204 dst->type = malloc(hlen, M_IP6OPT, canwait); \ 2205 if (dst->type == NULL) \ 2206 goto bad; \ 2207 memcpy(dst->type, src->type, hlen); \ 2208 } \ 2209 } while (/*CONSTCOND*/ 0) 2210 2211 static int 2212 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait) 2213 { 2214 dst->ip6po_hlim = src->ip6po_hlim; 2215 dst->ip6po_tclass = src->ip6po_tclass; 2216 dst->ip6po_flags = src->ip6po_flags; 2217 dst->ip6po_minmtu = src->ip6po_minmtu; 2218 dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr; 2219 if (src->ip6po_pktinfo) { 2220 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo), 2221 M_IP6OPT, canwait); 2222 if (dst->ip6po_pktinfo == NULL) 2223 goto bad; 2224 *dst->ip6po_pktinfo = *src->ip6po_pktinfo; 2225 } 2226 if (src->ip6po_nexthop) { 2227 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len, 2228 M_IP6OPT, canwait); 2229 if (dst->ip6po_nexthop == NULL) 2230 goto bad; 2231 memcpy(dst->ip6po_nexthop, src->ip6po_nexthop, 2232 src->ip6po_nexthop->sa_len); 2233 } 2234 PKTOPT_EXTHDRCPY(ip6po_hbh); 2235 PKTOPT_EXTHDRCPY(ip6po_dest1); 2236 PKTOPT_EXTHDRCPY(ip6po_dest2); 2237 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */ 2238 return (0); 2239 2240 bad: 2241 if (dst->ip6po_pktinfo) free(dst->ip6po_pktinfo, M_IP6OPT); 2242 if (dst->ip6po_nexthop) free(dst->ip6po_nexthop, M_IP6OPT); 2243 if (dst->ip6po_hbh) free(dst->ip6po_hbh, M_IP6OPT); 2244 if (dst->ip6po_dest1) free(dst->ip6po_dest1, M_IP6OPT); 2245 if (dst->ip6po_dest2) free(dst->ip6po_dest2, M_IP6OPT); 2246 if (dst->ip6po_rthdr) free(dst->ip6po_rthdr, M_IP6OPT); 2247 2248 return (ENOBUFS); 2249 } 2250 #undef PKTOPT_EXTHDRCPY 2251 2252 struct ip6_pktopts * 2253 ip6_copypktopts(struct ip6_pktopts *src, int canwait) 2254 { 2255 int error; 2256 struct ip6_pktopts *dst; 2257 2258 dst = malloc(sizeof(*dst), M_IP6OPT, canwait); 2259 if (dst == NULL) 2260 return (NULL); 2261 ip6_initpktopts(dst); 2262 2263 if ((error = copypktopts(dst, src, canwait)) != 0) { 2264 free(dst, M_IP6OPT); 2265 return (NULL); 2266 } 2267 2268 return (dst); 2269 } 2270 2271 void 2272 ip6_freepcbopts(struct ip6_pktopts *pktopt) 2273 { 2274 if (pktopt == NULL) 2275 return; 2276 2277 ip6_clearpktopts(pktopt, -1); 2278 2279 free(pktopt, M_IP6OPT); 2280 } 2281 2282 int 2283 ip6_get_membership(const struct sockopt *sopt, struct ifnet **ifp, void *v, 2284 size_t l) 2285 { 2286 struct ipv6_mreq mreq; 2287 int error; 2288 struct in6_addr *ia = &mreq.ipv6mr_multiaddr; 2289 struct in_addr *ia4 = (void *)&ia->s6_addr32[3]; 2290 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 2291 if (error != 0) 2292 return error; 2293 2294 if (IN6_IS_ADDR_UNSPECIFIED(ia)) { 2295 /* 2296 * We use the unspecified address to specify to accept 2297 * all multicast addresses. Only super user is allowed 2298 * to do this. 2299 */ 2300 if (kauth_authorize_network(curlwp->l_cred, KAUTH_NETWORK_IPV6, 2301 KAUTH_REQ_NETWORK_IPV6_JOIN_MULTICAST, NULL, NULL, NULL)) 2302 return EACCES; 2303 } else if (IN6_IS_ADDR_V4MAPPED(ia)) { 2304 // Don't bother if we are not going to use ifp. 2305 if (l == sizeof(*ia)) { 2306 memcpy(v, ia, l); 2307 return 0; 2308 } 2309 } else if (!IN6_IS_ADDR_MULTICAST(ia)) { 2310 return EINVAL; 2311 } 2312 2313 /* 2314 * If no interface was explicitly specified, choose an 2315 * appropriate one according to the given multicast address. 2316 */ 2317 if (mreq.ipv6mr_interface == 0) { 2318 struct rtentry *rt; 2319 union { 2320 struct sockaddr dst; 2321 struct sockaddr_in dst4; 2322 struct sockaddr_in6 dst6; 2323 } u; 2324 struct route ro; 2325 2326 /* 2327 * Look up the routing table for the 2328 * address, and choose the outgoing interface. 2329 * XXX: is it a good approach? 2330 */ 2331 memset(&ro, 0, sizeof(ro)); 2332 if (IN6_IS_ADDR_V4MAPPED(ia)) 2333 sockaddr_in_init(&u.dst4, ia4, 0); 2334 else 2335 sockaddr_in6_init(&u.dst6, ia, 0, 0, 0); 2336 error = rtcache_setdst(&ro, &u.dst); 2337 if (error != 0) 2338 return error; 2339 *ifp = (rt = rtcache_init(&ro)) != NULL ? rt->rt_ifp : NULL; 2340 rtcache_free(&ro); 2341 } else { 2342 /* 2343 * If the interface is specified, validate it. 2344 */ 2345 if ((*ifp = if_byindex(mreq.ipv6mr_interface)) == NULL) 2346 return ENXIO; /* XXX EINVAL? */ 2347 } 2348 if (sizeof(*ia) == l) 2349 memcpy(v, ia, l); 2350 else 2351 memcpy(v, ia4, l); 2352 return 0; 2353 } 2354 2355 /* 2356 * Set the IP6 multicast options in response to user setsockopt(). 2357 */ 2358 static int 2359 ip6_setmoptions(const struct sockopt *sopt, struct in6pcb *in6p) 2360 { 2361 int error = 0; 2362 u_int loop, ifindex; 2363 struct ipv6_mreq mreq; 2364 struct in6_addr ia; 2365 struct ifnet *ifp; 2366 struct ip6_moptions *im6o = in6p->in6p_moptions; 2367 struct in6_multi_mship *imm; 2368 2369 if (im6o == NULL) { 2370 /* 2371 * No multicast option buffer attached to the pcb; 2372 * allocate one and initialize to default values. 2373 */ 2374 im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_NOWAIT); 2375 if (im6o == NULL) 2376 return (ENOBUFS); 2377 in6p->in6p_moptions = im6o; 2378 im6o->im6o_multicast_ifp = NULL; 2379 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 2380 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP; 2381 LIST_INIT(&im6o->im6o_memberships); 2382 } 2383 2384 switch (sopt->sopt_name) { 2385 2386 case IPV6_MULTICAST_IF: 2387 /* 2388 * Select the interface for outgoing multicast packets. 2389 */ 2390 error = sockopt_get(sopt, &ifindex, sizeof(ifindex)); 2391 if (error != 0) 2392 break; 2393 2394 if (ifindex != 0) { 2395 if ((ifp = if_byindex(ifindex)) == NULL) { 2396 error = ENXIO; /* XXX EINVAL? */ 2397 break; 2398 } 2399 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 2400 error = EADDRNOTAVAIL; 2401 break; 2402 } 2403 } else 2404 ifp = NULL; 2405 im6o->im6o_multicast_ifp = ifp; 2406 break; 2407 2408 case IPV6_MULTICAST_HOPS: 2409 { 2410 /* 2411 * Set the IP6 hoplimit for outgoing multicast packets. 2412 */ 2413 int optval; 2414 2415 error = sockopt_getint(sopt, &optval); 2416 if (error != 0) 2417 break; 2418 2419 if (optval < -1 || optval >= 256) 2420 error = EINVAL; 2421 else if (optval == -1) 2422 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 2423 else 2424 im6o->im6o_multicast_hlim = optval; 2425 break; 2426 } 2427 2428 case IPV6_MULTICAST_LOOP: 2429 /* 2430 * Set the loopback flag for outgoing multicast packets. 2431 * Must be zero or one. 2432 */ 2433 error = sockopt_get(sopt, &loop, sizeof(loop)); 2434 if (error != 0) 2435 break; 2436 if (loop > 1) { 2437 error = EINVAL; 2438 break; 2439 } 2440 im6o->im6o_multicast_loop = loop; 2441 break; 2442 2443 case IPV6_JOIN_GROUP: 2444 /* 2445 * Add a multicast group membership. 2446 * Group must be a valid IP6 multicast address. 2447 */ 2448 if ((error = ip6_get_membership(sopt, &ifp, &ia, sizeof(ia)))) 2449 return error; 2450 2451 if (IN6_IS_ADDR_V4MAPPED(&ia)) { 2452 error = ip_setmoptions(&in6p->in6p_v4moptions, sopt); 2453 break; 2454 } 2455 /* 2456 * See if we found an interface, and confirm that it 2457 * supports multicast 2458 */ 2459 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 2460 error = EADDRNOTAVAIL; 2461 break; 2462 } 2463 2464 if (in6_setscope(&ia, ifp, NULL)) { 2465 error = EADDRNOTAVAIL; /* XXX: should not happen */ 2466 break; 2467 } 2468 2469 /* 2470 * See if the membership already exists. 2471 */ 2472 for (imm = im6o->im6o_memberships.lh_first; 2473 imm != NULL; imm = imm->i6mm_chain.le_next) 2474 if (imm->i6mm_maddr->in6m_ifp == ifp && 2475 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2476 &ia)) 2477 break; 2478 if (imm != NULL) { 2479 error = EADDRINUSE; 2480 break; 2481 } 2482 /* 2483 * Everything looks good; add a new record to the multicast 2484 * address list for the given interface. 2485 */ 2486 imm = in6_joingroup(ifp, &ia, &error, 0); 2487 if (imm == NULL) 2488 break; 2489 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); 2490 break; 2491 2492 case IPV6_LEAVE_GROUP: 2493 /* 2494 * Drop a multicast group membership. 2495 * Group must be a valid IP6 multicast address. 2496 */ 2497 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 2498 if (error != 0) 2499 break; 2500 2501 if (IN6_IS_ADDR_V4MAPPED(&mreq.ipv6mr_multiaddr)) { 2502 error = ip_setmoptions(&in6p->in6p_v4moptions, sopt); 2503 break; 2504 } 2505 /* 2506 * If an interface address was specified, get a pointer 2507 * to its ifnet structure. 2508 */ 2509 if (mreq.ipv6mr_interface != 0) { 2510 if ((ifp = if_byindex(mreq.ipv6mr_interface)) == NULL) { 2511 error = ENXIO; /* XXX EINVAL? */ 2512 break; 2513 } 2514 } else 2515 ifp = NULL; 2516 2517 /* Fill in the scope zone ID */ 2518 if (ifp) { 2519 if (in6_setscope(&mreq.ipv6mr_multiaddr, ifp, NULL)) { 2520 /* XXX: should not happen */ 2521 error = EADDRNOTAVAIL; 2522 break; 2523 } 2524 } else if (mreq.ipv6mr_interface != 0) { 2525 /* 2526 * XXX: This case would happens when the (positive) 2527 * index is in the valid range, but the corresponding 2528 * interface has been detached dynamically. The above 2529 * check probably avoids such case to happen here, but 2530 * we check it explicitly for safety. 2531 */ 2532 error = EADDRNOTAVAIL; 2533 break; 2534 } else { /* ipv6mr_interface == 0 */ 2535 struct sockaddr_in6 sa6_mc; 2536 2537 /* 2538 * The API spec says as follows: 2539 * If the interface index is specified as 0, the 2540 * system may choose a multicast group membership to 2541 * drop by matching the multicast address only. 2542 * On the other hand, we cannot disambiguate the scope 2543 * zone unless an interface is provided. Thus, we 2544 * check if there's ambiguity with the default scope 2545 * zone as the last resort. 2546 */ 2547 sockaddr_in6_init(&sa6_mc, &mreq.ipv6mr_multiaddr, 2548 0, 0, 0); 2549 error = sa6_embedscope(&sa6_mc, ip6_use_defzone); 2550 if (error != 0) 2551 break; 2552 mreq.ipv6mr_multiaddr = sa6_mc.sin6_addr; 2553 } 2554 2555 /* 2556 * Find the membership in the membership list. 2557 */ 2558 for (imm = im6o->im6o_memberships.lh_first; 2559 imm != NULL; imm = imm->i6mm_chain.le_next) { 2560 if ((ifp == NULL || imm->i6mm_maddr->in6m_ifp == ifp) && 2561 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2562 &mreq.ipv6mr_multiaddr)) 2563 break; 2564 } 2565 if (imm == NULL) { 2566 /* Unable to resolve interface */ 2567 error = EADDRNOTAVAIL; 2568 break; 2569 } 2570 /* 2571 * Give up the multicast address record to which the 2572 * membership points. 2573 */ 2574 LIST_REMOVE(imm, i6mm_chain); 2575 in6_leavegroup(imm); 2576 break; 2577 2578 default: 2579 error = EOPNOTSUPP; 2580 break; 2581 } 2582 2583 /* 2584 * If all options have default values, no need to keep the mbuf. 2585 */ 2586 if (im6o->im6o_multicast_ifp == NULL && 2587 im6o->im6o_multicast_hlim == ip6_defmcasthlim && 2588 im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP && 2589 im6o->im6o_memberships.lh_first == NULL) { 2590 free(in6p->in6p_moptions, M_IPMOPTS); 2591 in6p->in6p_moptions = NULL; 2592 } 2593 2594 return (error); 2595 } 2596 2597 /* 2598 * Return the IP6 multicast options in response to user getsockopt(). 2599 */ 2600 static int 2601 ip6_getmoptions(struct sockopt *sopt, struct in6pcb *in6p) 2602 { 2603 u_int optval; 2604 int error; 2605 struct ip6_moptions *im6o = in6p->in6p_moptions; 2606 2607 switch (sopt->sopt_name) { 2608 case IPV6_MULTICAST_IF: 2609 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL) 2610 optval = 0; 2611 else 2612 optval = im6o->im6o_multicast_ifp->if_index; 2613 2614 error = sockopt_set(sopt, &optval, sizeof(optval)); 2615 break; 2616 2617 case IPV6_MULTICAST_HOPS: 2618 if (im6o == NULL) 2619 optval = ip6_defmcasthlim; 2620 else 2621 optval = im6o->im6o_multicast_hlim; 2622 2623 error = sockopt_set(sopt, &optval, sizeof(optval)); 2624 break; 2625 2626 case IPV6_MULTICAST_LOOP: 2627 if (im6o == NULL) 2628 optval = IPV6_DEFAULT_MULTICAST_LOOP; 2629 else 2630 optval = im6o->im6o_multicast_loop; 2631 2632 error = sockopt_set(sopt, &optval, sizeof(optval)); 2633 break; 2634 2635 default: 2636 error = EOPNOTSUPP; 2637 } 2638 2639 return (error); 2640 } 2641 2642 /* 2643 * Discard the IP6 multicast options. 2644 */ 2645 void 2646 ip6_freemoptions(struct ip6_moptions *im6o) 2647 { 2648 struct in6_multi_mship *imm; 2649 2650 if (im6o == NULL) 2651 return; 2652 2653 while ((imm = im6o->im6o_memberships.lh_first) != NULL) { 2654 LIST_REMOVE(imm, i6mm_chain); 2655 in6_leavegroup(imm); 2656 } 2657 free(im6o, M_IPMOPTS); 2658 } 2659 2660 /* 2661 * Set IPv6 outgoing packet options based on advanced API. 2662 */ 2663 int 2664 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt, 2665 struct ip6_pktopts *stickyopt, kauth_cred_t cred, int uproto) 2666 { 2667 struct cmsghdr *cm = 0; 2668 2669 if (control == NULL || opt == NULL) 2670 return (EINVAL); 2671 2672 ip6_initpktopts(opt); 2673 if (stickyopt) { 2674 int error; 2675 2676 /* 2677 * If stickyopt is provided, make a local copy of the options 2678 * for this particular packet, then override them by ancillary 2679 * objects. 2680 * XXX: copypktopts() does not copy the cached route to a next 2681 * hop (if any). This is not very good in terms of efficiency, 2682 * but we can allow this since this option should be rarely 2683 * used. 2684 */ 2685 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0) 2686 return (error); 2687 } 2688 2689 /* 2690 * XXX: Currently, we assume all the optional information is stored 2691 * in a single mbuf. 2692 */ 2693 if (control->m_next) 2694 return (EINVAL); 2695 2696 /* XXX if cm->cmsg_len is not aligned, control->m_len can become <0 */ 2697 for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len), 2698 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 2699 int error; 2700 2701 if (control->m_len < CMSG_LEN(0)) 2702 return (EINVAL); 2703 2704 cm = mtod(control, struct cmsghdr *); 2705 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len) 2706 return (EINVAL); 2707 if (cm->cmsg_level != IPPROTO_IPV6) 2708 continue; 2709 2710 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm), 2711 cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto); 2712 if (error) 2713 return (error); 2714 } 2715 2716 return (0); 2717 } 2718 2719 /* 2720 * Set a particular packet option, as a sticky option or an ancillary data 2721 * item. "len" can be 0 only when it's a sticky option. 2722 * We have 4 cases of combination of "sticky" and "cmsg": 2723 * "sticky=0, cmsg=0": impossible 2724 * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data 2725 * "sticky=1, cmsg=0": RFC3542 socket option 2726 * "sticky=1, cmsg=1": RFC2292 socket option 2727 */ 2728 static int 2729 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt, 2730 kauth_cred_t cred, int sticky, int cmsg, int uproto) 2731 { 2732 int minmtupolicy; 2733 int error; 2734 2735 if (!sticky && !cmsg) { 2736 #ifdef DIAGNOSTIC 2737 printf("ip6_setpktopt: impossible case\n"); 2738 #endif 2739 return (EINVAL); 2740 } 2741 2742 /* 2743 * IPV6_2292xxx is for backward compatibility to RFC2292, and should 2744 * not be specified in the context of RFC3542. Conversely, 2745 * RFC3542 types should not be specified in the context of RFC2292. 2746 */ 2747 if (!cmsg) { 2748 switch (optname) { 2749 case IPV6_2292PKTINFO: 2750 case IPV6_2292HOPLIMIT: 2751 case IPV6_2292NEXTHOP: 2752 case IPV6_2292HOPOPTS: 2753 case IPV6_2292DSTOPTS: 2754 case IPV6_2292RTHDR: 2755 case IPV6_2292PKTOPTIONS: 2756 return (ENOPROTOOPT); 2757 } 2758 } 2759 if (sticky && cmsg) { 2760 switch (optname) { 2761 case IPV6_PKTINFO: 2762 case IPV6_HOPLIMIT: 2763 case IPV6_NEXTHOP: 2764 case IPV6_HOPOPTS: 2765 case IPV6_DSTOPTS: 2766 case IPV6_RTHDRDSTOPTS: 2767 case IPV6_RTHDR: 2768 case IPV6_USE_MIN_MTU: 2769 case IPV6_DONTFRAG: 2770 case IPV6_OTCLASS: 2771 case IPV6_TCLASS: 2772 case IPV6_PREFER_TEMPADDR: /* XXX not an RFC3542 option */ 2773 return (ENOPROTOOPT); 2774 } 2775 } 2776 2777 switch (optname) { 2778 #ifdef RFC2292 2779 case IPV6_2292PKTINFO: 2780 #endif 2781 case IPV6_PKTINFO: 2782 { 2783 struct ifnet *ifp = NULL; 2784 struct in6_pktinfo *pktinfo; 2785 2786 if (len != sizeof(struct in6_pktinfo)) 2787 return (EINVAL); 2788 2789 pktinfo = (struct in6_pktinfo *)buf; 2790 2791 /* 2792 * An application can clear any sticky IPV6_PKTINFO option by 2793 * doing a "regular" setsockopt with ipi6_addr being 2794 * in6addr_any and ipi6_ifindex being zero. 2795 * [RFC 3542, Section 6] 2796 */ 2797 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo && 2798 pktinfo->ipi6_ifindex == 0 && 2799 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2800 ip6_clearpktopts(opt, optname); 2801 break; 2802 } 2803 2804 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO && 2805 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2806 return (EINVAL); 2807 } 2808 2809 /* Validate the interface index if specified. */ 2810 if (pktinfo->ipi6_ifindex) { 2811 ifp = if_byindex(pktinfo->ipi6_ifindex); 2812 if (ifp == NULL) 2813 return (ENXIO); 2814 } 2815 2816 /* 2817 * We store the address anyway, and let in6_selectsrc() 2818 * validate the specified address. This is because ipi6_addr 2819 * may not have enough information about its scope zone, and 2820 * we may need additional information (such as outgoing 2821 * interface or the scope zone of a destination address) to 2822 * disambiguate the scope. 2823 * XXX: the delay of the validation may confuse the 2824 * application when it is used as a sticky option. 2825 */ 2826 if (opt->ip6po_pktinfo == NULL) { 2827 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo), 2828 M_IP6OPT, M_NOWAIT); 2829 if (opt->ip6po_pktinfo == NULL) 2830 return (ENOBUFS); 2831 } 2832 memcpy(opt->ip6po_pktinfo, pktinfo, sizeof(*pktinfo)); 2833 break; 2834 } 2835 2836 #ifdef RFC2292 2837 case IPV6_2292HOPLIMIT: 2838 #endif 2839 case IPV6_HOPLIMIT: 2840 { 2841 int *hlimp; 2842 2843 /* 2844 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT 2845 * to simplify the ordering among hoplimit options. 2846 */ 2847 if (optname == IPV6_HOPLIMIT && sticky) 2848 return (ENOPROTOOPT); 2849 2850 if (len != sizeof(int)) 2851 return (EINVAL); 2852 hlimp = (int *)buf; 2853 if (*hlimp < -1 || *hlimp > 255) 2854 return (EINVAL); 2855 2856 opt->ip6po_hlim = *hlimp; 2857 break; 2858 } 2859 2860 case IPV6_OTCLASS: 2861 if (len != sizeof(u_int8_t)) 2862 return (EINVAL); 2863 2864 opt->ip6po_tclass = *(u_int8_t *)buf; 2865 break; 2866 2867 case IPV6_TCLASS: 2868 { 2869 int tclass; 2870 2871 if (len != sizeof(int)) 2872 return (EINVAL); 2873 tclass = *(int *)buf; 2874 if (tclass < -1 || tclass > 255) 2875 return (EINVAL); 2876 2877 opt->ip6po_tclass = tclass; 2878 break; 2879 } 2880 2881 #ifdef RFC2292 2882 case IPV6_2292NEXTHOP: 2883 #endif 2884 case IPV6_NEXTHOP: 2885 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2886 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2887 if (error) 2888 return (error); 2889 2890 if (len == 0) { /* just remove the option */ 2891 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2892 break; 2893 } 2894 2895 /* check if cmsg_len is large enough for sa_len */ 2896 if (len < sizeof(struct sockaddr) || len < *buf) 2897 return (EINVAL); 2898 2899 switch (((struct sockaddr *)buf)->sa_family) { 2900 case AF_INET6: 2901 { 2902 struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf; 2903 2904 if (sa6->sin6_len != sizeof(struct sockaddr_in6)) 2905 return (EINVAL); 2906 2907 if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) || 2908 IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 2909 return (EINVAL); 2910 } 2911 if ((error = sa6_embedscope(sa6, ip6_use_defzone)) 2912 != 0) { 2913 return (error); 2914 } 2915 break; 2916 } 2917 case AF_LINK: /* eventually be supported? */ 2918 default: 2919 return (EAFNOSUPPORT); 2920 } 2921 2922 /* turn off the previous option, then set the new option. */ 2923 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2924 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT); 2925 if (opt->ip6po_nexthop == NULL) 2926 return (ENOBUFS); 2927 memcpy(opt->ip6po_nexthop, buf, *buf); 2928 break; 2929 2930 #ifdef RFC2292 2931 case IPV6_2292HOPOPTS: 2932 #endif 2933 case IPV6_HOPOPTS: 2934 { 2935 struct ip6_hbh *hbh; 2936 int hbhlen; 2937 2938 /* 2939 * XXX: We don't allow a non-privileged user to set ANY HbH 2940 * options, since per-option restriction has too much 2941 * overhead. 2942 */ 2943 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2944 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2945 if (error) 2946 return (error); 2947 2948 if (len == 0) { 2949 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2950 break; /* just remove the option */ 2951 } 2952 2953 /* message length validation */ 2954 if (len < sizeof(struct ip6_hbh)) 2955 return (EINVAL); 2956 hbh = (struct ip6_hbh *)buf; 2957 hbhlen = (hbh->ip6h_len + 1) << 3; 2958 if (len != hbhlen) 2959 return (EINVAL); 2960 2961 /* turn off the previous option, then set the new option. */ 2962 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2963 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT); 2964 if (opt->ip6po_hbh == NULL) 2965 return (ENOBUFS); 2966 memcpy(opt->ip6po_hbh, hbh, hbhlen); 2967 2968 break; 2969 } 2970 2971 #ifdef RFC2292 2972 case IPV6_2292DSTOPTS: 2973 #endif 2974 case IPV6_DSTOPTS: 2975 case IPV6_RTHDRDSTOPTS: 2976 { 2977 struct ip6_dest *dest, **newdest = NULL; 2978 int destlen; 2979 2980 /* XXX: see the comment for IPV6_HOPOPTS */ 2981 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2982 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2983 if (error) 2984 return (error); 2985 2986 if (len == 0) { 2987 ip6_clearpktopts(opt, optname); 2988 break; /* just remove the option */ 2989 } 2990 2991 /* message length validation */ 2992 if (len < sizeof(struct ip6_dest)) 2993 return (EINVAL); 2994 dest = (struct ip6_dest *)buf; 2995 destlen = (dest->ip6d_len + 1) << 3; 2996 if (len != destlen) 2997 return (EINVAL); 2998 /* 2999 * Determine the position that the destination options header 3000 * should be inserted; before or after the routing header. 3001 */ 3002 switch (optname) { 3003 case IPV6_2292DSTOPTS: 3004 /* 3005 * The old advanced API is ambiguous on this point. 3006 * Our approach is to determine the position based 3007 * according to the existence of a routing header. 3008 * Note, however, that this depends on the order of the 3009 * extension headers in the ancillary data; the 1st 3010 * part of the destination options header must appear 3011 * before the routing header in the ancillary data, 3012 * too. 3013 * RFC3542 solved the ambiguity by introducing 3014 * separate ancillary data or option types. 3015 */ 3016 if (opt->ip6po_rthdr == NULL) 3017 newdest = &opt->ip6po_dest1; 3018 else 3019 newdest = &opt->ip6po_dest2; 3020 break; 3021 case IPV6_RTHDRDSTOPTS: 3022 newdest = &opt->ip6po_dest1; 3023 break; 3024 case IPV6_DSTOPTS: 3025 newdest = &opt->ip6po_dest2; 3026 break; 3027 } 3028 3029 /* turn off the previous option, then set the new option. */ 3030 ip6_clearpktopts(opt, optname); 3031 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT); 3032 if (*newdest == NULL) 3033 return (ENOBUFS); 3034 memcpy(*newdest, dest, destlen); 3035 3036 break; 3037 } 3038 3039 #ifdef RFC2292 3040 case IPV6_2292RTHDR: 3041 #endif 3042 case IPV6_RTHDR: 3043 { 3044 struct ip6_rthdr *rth; 3045 int rthlen; 3046 3047 if (len == 0) { 3048 ip6_clearpktopts(opt, IPV6_RTHDR); 3049 break; /* just remove the option */ 3050 } 3051 3052 /* message length validation */ 3053 if (len < sizeof(struct ip6_rthdr)) 3054 return (EINVAL); 3055 rth = (struct ip6_rthdr *)buf; 3056 rthlen = (rth->ip6r_len + 1) << 3; 3057 if (len != rthlen) 3058 return (EINVAL); 3059 switch (rth->ip6r_type) { 3060 case IPV6_RTHDR_TYPE_0: 3061 if (rth->ip6r_len == 0) /* must contain one addr */ 3062 return (EINVAL); 3063 if (rth->ip6r_len % 2) /* length must be even */ 3064 return (EINVAL); 3065 if (rth->ip6r_len / 2 != rth->ip6r_segleft) 3066 return (EINVAL); 3067 break; 3068 default: 3069 return (EINVAL); /* not supported */ 3070 } 3071 /* turn off the previous option */ 3072 ip6_clearpktopts(opt, IPV6_RTHDR); 3073 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT); 3074 if (opt->ip6po_rthdr == NULL) 3075 return (ENOBUFS); 3076 memcpy(opt->ip6po_rthdr, rth, rthlen); 3077 break; 3078 } 3079 3080 case IPV6_USE_MIN_MTU: 3081 if (len != sizeof(int)) 3082 return (EINVAL); 3083 minmtupolicy = *(int *)buf; 3084 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY && 3085 minmtupolicy != IP6PO_MINMTU_DISABLE && 3086 minmtupolicy != IP6PO_MINMTU_ALL) { 3087 return (EINVAL); 3088 } 3089 opt->ip6po_minmtu = minmtupolicy; 3090 break; 3091 3092 case IPV6_DONTFRAG: 3093 if (len != sizeof(int)) 3094 return (EINVAL); 3095 3096 if (uproto == IPPROTO_TCP || *(int *)buf == 0) { 3097 /* 3098 * we ignore this option for TCP sockets. 3099 * (RFC3542 leaves this case unspecified.) 3100 */ 3101 opt->ip6po_flags &= ~IP6PO_DONTFRAG; 3102 } else 3103 opt->ip6po_flags |= IP6PO_DONTFRAG; 3104 break; 3105 3106 case IPV6_PREFER_TEMPADDR: 3107 { 3108 int preftemp; 3109 3110 if (len != sizeof(int)) 3111 return (EINVAL); 3112 preftemp = *(int *)buf; 3113 switch (preftemp) { 3114 case IP6PO_TEMPADDR_SYSTEM: 3115 case IP6PO_TEMPADDR_NOTPREFER: 3116 case IP6PO_TEMPADDR_PREFER: 3117 break; 3118 default: 3119 return (EINVAL); 3120 } 3121 opt->ip6po_prefer_tempaddr = preftemp; 3122 break; 3123 } 3124 3125 default: 3126 return (ENOPROTOOPT); 3127 } /* end of switch */ 3128 3129 return (0); 3130 } 3131 3132 /* 3133 * Routine called from ip6_output() to loop back a copy of an IP6 multicast 3134 * packet to the input queue of a specified interface. Note that this 3135 * calls the output routine of the loopback "driver", but with an interface 3136 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 3137 */ 3138 void 3139 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, 3140 const struct sockaddr_in6 *dst) 3141 { 3142 struct mbuf *copym; 3143 struct ip6_hdr *ip6; 3144 3145 copym = m_copy(m, 0, M_COPYALL); 3146 if (copym == NULL) 3147 return; 3148 3149 /* 3150 * Make sure to deep-copy IPv6 header portion in case the data 3151 * is in an mbuf cluster, so that we can safely override the IPv6 3152 * header portion later. 3153 */ 3154 if ((copym->m_flags & M_EXT) != 0 || 3155 copym->m_len < sizeof(struct ip6_hdr)) { 3156 copym = m_pullup(copym, sizeof(struct ip6_hdr)); 3157 if (copym == NULL) 3158 return; 3159 } 3160 3161 #ifdef DIAGNOSTIC 3162 if (copym->m_len < sizeof(*ip6)) { 3163 m_freem(copym); 3164 return; 3165 } 3166 #endif 3167 3168 ip6 = mtod(copym, struct ip6_hdr *); 3169 /* 3170 * clear embedded scope identifiers if necessary. 3171 * in6_clearscope will touch the addresses only when necessary. 3172 */ 3173 in6_clearscope(&ip6->ip6_src); 3174 in6_clearscope(&ip6->ip6_dst); 3175 3176 (void)looutput(ifp, copym, (const struct sockaddr *)dst, NULL); 3177 } 3178 3179 /* 3180 * Chop IPv6 header off from the payload. 3181 */ 3182 static int 3183 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs) 3184 { 3185 struct mbuf *mh; 3186 struct ip6_hdr *ip6; 3187 3188 ip6 = mtod(m, struct ip6_hdr *); 3189 if (m->m_len > sizeof(*ip6)) { 3190 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 3191 if (mh == 0) { 3192 m_freem(m); 3193 return ENOBUFS; 3194 } 3195 M_MOVE_PKTHDR(mh, m); 3196 MH_ALIGN(mh, sizeof(*ip6)); 3197 m->m_len -= sizeof(*ip6); 3198 m->m_data += sizeof(*ip6); 3199 mh->m_next = m; 3200 m = mh; 3201 m->m_len = sizeof(*ip6); 3202 bcopy((void *)ip6, mtod(m, void *), sizeof(*ip6)); 3203 } 3204 exthdrs->ip6e_ip6 = m; 3205 return 0; 3206 } 3207 3208 /* 3209 * Compute IPv6 extension header length. 3210 */ 3211 int 3212 ip6_optlen(struct in6pcb *in6p) 3213 { 3214 int len; 3215 3216 if (!in6p->in6p_outputopts) 3217 return 0; 3218 3219 len = 0; 3220 #define elen(x) \ 3221 (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0) 3222 3223 len += elen(in6p->in6p_outputopts->ip6po_hbh); 3224 len += elen(in6p->in6p_outputopts->ip6po_dest1); 3225 len += elen(in6p->in6p_outputopts->ip6po_rthdr); 3226 len += elen(in6p->in6p_outputopts->ip6po_dest2); 3227 return len; 3228 #undef elen 3229 } 3230