1 /* $NetBSD: ip6_output.c,v 1.155 2013/10/03 20:27:55 christos 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 1.155 2013/10/03 20:27:55 christos 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/icmp6.h> 90 #include <netinet/in_offload.h> 91 #include <netinet/portalgo.h> 92 #include <netinet6/in6_offload.h> 93 #include <netinet6/ip6_var.h> 94 #include <netinet6/ip6_private.h> 95 #include <netinet6/in6_pcb.h> 96 #include <netinet6/nd6.h> 97 #include <netinet6/ip6protosw.h> 98 #include <netinet6/scope6_var.h> 99 100 #ifdef IPSEC 101 #include <netipsec/ipsec.h> 102 #include <netipsec/ipsec6.h> 103 #include <netipsec/key.h> 104 #include <netipsec/xform.h> 105 #endif 106 107 108 #include <net/net_osdep.h> 109 110 extern pfil_head_t *inet6_pfil_hook; /* XXX */ 111 112 struct ip6_exthdrs { 113 struct mbuf *ip6e_ip6; 114 struct mbuf *ip6e_hbh; 115 struct mbuf *ip6e_dest1; 116 struct mbuf *ip6e_rthdr; 117 struct mbuf *ip6e_dest2; 118 }; 119 120 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, 121 kauth_cred_t, int); 122 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *); 123 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, kauth_cred_t, 124 int, int, int); 125 static int ip6_setmoptions(const struct sockopt *, struct ip6_moptions **); 126 static int ip6_getmoptions(struct sockopt *, struct ip6_moptions *); 127 static int ip6_copyexthdr(struct mbuf **, void *, int); 128 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int, 129 struct ip6_frag **); 130 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t); 131 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *); 132 static int ip6_getpmtu(struct route *, struct route *, struct ifnet *, 133 const struct in6_addr *, u_long *, int *); 134 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int); 135 136 #ifdef RFC2292 137 static int ip6_pcbopts(struct ip6_pktopts **, struct socket *, struct sockopt *); 138 #endif 139 140 /* 141 * IP6 output. The packet in mbuf chain m contains a skeletal IP6 142 * header (with pri, len, nxt, hlim, src, dst). 143 * This function may modify ver and hlim only. 144 * The mbuf chain containing the packet will be freed. 145 * The mbuf opt, if present, will not be freed. 146 * 147 * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and 148 * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one, 149 * which is rt_rmx.rmx_mtu. 150 */ 151 int 152 ip6_output( 153 struct mbuf *m0, 154 struct ip6_pktopts *opt, 155 struct route *ro, 156 int flags, 157 struct ip6_moptions *im6o, 158 struct socket *so, 159 struct ifnet **ifpp /* XXX: just for statistics */ 160 ) 161 { 162 struct ip6_hdr *ip6, *mhip6; 163 struct ifnet *ifp, *origifp; 164 struct mbuf *m = m0; 165 int hlen, tlen, len, off; 166 bool tso; 167 struct route ip6route; 168 struct rtentry *rt = NULL; 169 const struct sockaddr_in6 *dst = NULL; 170 struct sockaddr_in6 src_sa, dst_sa; 171 int error = 0; 172 struct in6_ifaddr *ia = NULL; 173 u_long mtu; 174 int alwaysfrag, dontfrag; 175 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; 176 struct ip6_exthdrs exthdrs; 177 struct in6_addr finaldst, src0, dst0; 178 u_int32_t zone; 179 struct route *ro_pmtu = NULL; 180 int hdrsplit = 0; 181 int needipsec = 0; 182 #ifdef IPSEC 183 struct secpolicy *sp = NULL; 184 int s; 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 /* Check the security policy (SP) for the packet */ 245 246 sp = ipsec6_check_policy(m,so,flags,&needipsec,&error); 247 if (error != 0) { 248 /* 249 * Hack: -EINVAL is used to signal that a packet 250 * should be silently discarded. This is typically 251 * because we asked key management for an SA and 252 * it was delayed (e.g. kicked up to IKE). 253 */ 254 if (error == -EINVAL) 255 error = 0; 256 goto freehdrs; 257 } 258 #endif /* IPSEC */ 259 260 261 if (needipsec && 262 (m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0) { 263 in6_delayed_cksum(m); 264 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 265 } 266 267 268 /* 269 * If we need IPsec, or there is at least one extension header, 270 * separate IP6 header from the payload. 271 */ 272 if ((needipsec || optlen) && !hdrsplit) { 273 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 274 m = NULL; 275 goto freehdrs; 276 } 277 m = exthdrs.ip6e_ip6; 278 hdrsplit++; 279 } 280 281 /* adjust pointer */ 282 ip6 = mtod(m, struct ip6_hdr *); 283 284 /* adjust mbuf packet header length */ 285 m->m_pkthdr.len += optlen; 286 plen = m->m_pkthdr.len - sizeof(*ip6); 287 288 /* If this is a jumbo payload, insert a jumbo payload option. */ 289 if (plen > IPV6_MAXPACKET) { 290 if (!hdrsplit) { 291 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 292 m = NULL; 293 goto freehdrs; 294 } 295 m = exthdrs.ip6e_ip6; 296 hdrsplit++; 297 } 298 /* adjust pointer */ 299 ip6 = mtod(m, struct ip6_hdr *); 300 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) 301 goto freehdrs; 302 optlen += 8; /* XXX JUMBOOPTLEN */ 303 ip6->ip6_plen = 0; 304 } else 305 ip6->ip6_plen = htons(plen); 306 307 /* 308 * Concatenate headers and fill in next header fields. 309 * Here we have, on "m" 310 * IPv6 payload 311 * and we insert headers accordingly. Finally, we should be getting: 312 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 313 * 314 * during the header composing process, "m" points to IPv6 header. 315 * "mprev" points to an extension header prior to esp. 316 */ 317 { 318 u_char *nexthdrp = &ip6->ip6_nxt; 319 struct mbuf *mprev = m; 320 321 /* 322 * we treat dest2 specially. this makes IPsec processing 323 * much easier. the goal here is to make mprev point the 324 * mbuf prior to dest2. 325 * 326 * result: IPv6 dest2 payload 327 * m and mprev will point to IPv6 header. 328 */ 329 if (exthdrs.ip6e_dest2) { 330 if (!hdrsplit) 331 panic("assumption failed: hdr not split"); 332 exthdrs.ip6e_dest2->m_next = m->m_next; 333 m->m_next = exthdrs.ip6e_dest2; 334 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; 335 ip6->ip6_nxt = IPPROTO_DSTOPTS; 336 } 337 338 #define MAKE_CHAIN(m, mp, p, i)\ 339 do {\ 340 if (m) {\ 341 if (!hdrsplit) \ 342 panic("assumption failed: hdr not split"); \ 343 *mtod((m), u_char *) = *(p);\ 344 *(p) = (i);\ 345 p = mtod((m), u_char *);\ 346 (m)->m_next = (mp)->m_next;\ 347 (mp)->m_next = (m);\ 348 (mp) = (m);\ 349 }\ 350 } while (/*CONSTCOND*/ 0) 351 /* 352 * result: IPv6 hbh dest1 rthdr dest2 payload 353 * m will point to IPv6 header. mprev will point to the 354 * extension header prior to dest2 (rthdr in the above case). 355 */ 356 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); 357 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, 358 IPPROTO_DSTOPTS); 359 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, 360 IPPROTO_ROUTING); 361 362 M_CSUM_DATA_IPv6_HL_SET(m->m_pkthdr.csum_data, 363 sizeof(struct ip6_hdr) + optlen); 364 } 365 366 /* 367 * If there is a routing header, replace destination address field 368 * with the first hop of the routing header. 369 */ 370 if (exthdrs.ip6e_rthdr) { 371 struct ip6_rthdr *rh; 372 struct ip6_rthdr0 *rh0; 373 struct in6_addr *addr; 374 struct sockaddr_in6 sa; 375 376 rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr, 377 struct ip6_rthdr *)); 378 finaldst = ip6->ip6_dst; 379 switch (rh->ip6r_type) { 380 case IPV6_RTHDR_TYPE_0: 381 rh0 = (struct ip6_rthdr0 *)rh; 382 addr = (struct in6_addr *)(rh0 + 1); 383 384 /* 385 * construct a sockaddr_in6 form of 386 * the first hop. 387 * 388 * XXX: we may not have enough 389 * information about its scope zone; 390 * there is no standard API to pass 391 * the information from the 392 * application. 393 */ 394 sockaddr_in6_init(&sa, addr, 0, 0, 0); 395 if ((error = sa6_embedscope(&sa, 396 ip6_use_defzone)) != 0) { 397 goto bad; 398 } 399 ip6->ip6_dst = sa.sin6_addr; 400 (void)memmove(&addr[0], &addr[1], 401 sizeof(struct in6_addr) * 402 (rh0->ip6r0_segleft - 1)); 403 addr[rh0->ip6r0_segleft - 1] = finaldst; 404 /* XXX */ 405 in6_clearscope(addr + rh0->ip6r0_segleft - 1); 406 break; 407 default: /* is it possible? */ 408 error = EINVAL; 409 goto bad; 410 } 411 } 412 413 /* Source address validation */ 414 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && 415 (flags & IPV6_UNSPECSRC) == 0) { 416 error = EOPNOTSUPP; 417 IP6_STATINC(IP6_STAT_BADSCOPE); 418 goto bad; 419 } 420 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { 421 error = EOPNOTSUPP; 422 IP6_STATINC(IP6_STAT_BADSCOPE); 423 goto bad; 424 } 425 426 IP6_STATINC(IP6_STAT_LOCALOUT); 427 428 /* 429 * Route packet. 430 */ 431 /* initialize cached route */ 432 if (ro == NULL) { 433 ro = &ip6route; 434 } 435 ro_pmtu = ro; 436 if (opt && opt->ip6po_rthdr) 437 ro = &opt->ip6po_route; 438 439 /* 440 * if specified, try to fill in the traffic class field. 441 * do not override if a non-zero value is already set. 442 * we check the diffserv field and the ecn field separately. 443 */ 444 if (opt && opt->ip6po_tclass >= 0) { 445 int mask = 0; 446 447 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0) 448 mask |= 0xfc; 449 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0) 450 mask |= 0x03; 451 if (mask != 0) 452 ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20); 453 } 454 455 /* fill in or override the hop limit field, if necessary. */ 456 if (opt && opt->ip6po_hlim != -1) 457 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 458 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 459 if (im6o != NULL) 460 ip6->ip6_hlim = im6o->im6o_multicast_hlim; 461 else 462 ip6->ip6_hlim = ip6_defmcasthlim; 463 } 464 465 #ifdef IPSEC 466 if (needipsec) { 467 s = splsoftnet(); 468 error = ipsec6_process_packet(m,sp->req); 469 470 /* 471 * Preserve KAME behaviour: ENOENT can be returned 472 * when an SA acquire is in progress. Don't propagate 473 * this to user-level; it confuses applications. 474 * XXX this will go away when the SADB is redone. 475 */ 476 if (error == ENOENT) 477 error = 0; 478 splx(s); 479 goto done; 480 } 481 #endif /* IPSEC */ 482 483 484 485 /* 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 if (dst == NULL) 547 dst = satocsin6(rtcache_getdst(ro)); 548 KASSERT(dst != NULL); 549 } else if (opt && rtcache_validate(&opt->ip6po_nextroute) != NULL) { 550 /* 551 * The nexthop is explicitly specified by the 552 * application. We assume the next hop is an IPv6 553 * address. 554 */ 555 dst = (struct sockaddr_in6 *)opt->ip6po_nexthop; 556 } else if ((rt->rt_flags & RTF_GATEWAY)) 557 dst = (struct sockaddr_in6 *)rt->rt_gateway; 558 else if (dst == NULL) 559 dst = satocsin6(rtcache_getdst(ro)); 560 561 /* 562 * XXXXXX: original code follows: 563 */ 564 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 565 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ 566 else { 567 struct in6_multi *in6m; 568 569 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; 570 571 in6_ifstat_inc(ifp, ifs6_out_mcast); 572 573 /* 574 * Confirm that the outgoing interface supports multicast. 575 */ 576 if (!(ifp->if_flags & IFF_MULTICAST)) { 577 IP6_STATINC(IP6_STAT_NOROUTE); 578 in6_ifstat_inc(ifp, ifs6_out_discard); 579 error = ENETUNREACH; 580 goto bad; 581 } 582 583 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m); 584 if (in6m != NULL && 585 (im6o == NULL || im6o->im6o_multicast_loop)) { 586 /* 587 * If we belong to the destination multicast group 588 * on the outgoing interface, and the caller did not 589 * forbid loopback, loop back a copy. 590 */ 591 KASSERT(dst != NULL); 592 ip6_mloopback(ifp, m, dst); 593 } else { 594 /* 595 * If we are acting as a multicast router, perform 596 * multicast forwarding as if the packet had just 597 * arrived on the interface to which we are about 598 * to send. The multicast forwarding function 599 * recursively calls this function, using the 600 * IPV6_FORWARDING flag to prevent infinite recursion. 601 * 602 * Multicasts that are looped back by ip6_mloopback(), 603 * above, will be forwarded by the ip6_input() routine, 604 * if necessary. 605 */ 606 if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) { 607 if (ip6_mforward(ip6, ifp, m) != 0) { 608 m_freem(m); 609 goto done; 610 } 611 } 612 } 613 /* 614 * Multicasts with a hoplimit of zero may be looped back, 615 * above, but must not be transmitted on a network. 616 * Also, multicasts addressed to the loopback interface 617 * are not sent -- the above call to ip6_mloopback() will 618 * loop back a copy if this host actually belongs to the 619 * destination group on the loopback interface. 620 */ 621 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) || 622 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) { 623 m_freem(m); 624 goto done; 625 } 626 } 627 628 /* 629 * Fill the outgoing inteface to tell the upper layer 630 * to increment per-interface statistics. 631 */ 632 if (ifpp) 633 *ifpp = ifp; 634 635 /* Determine path MTU. */ 636 if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu, 637 &alwaysfrag)) != 0) 638 goto bad; 639 640 /* 641 * The caller of this function may specify to use the minimum MTU 642 * in some cases. 643 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU 644 * setting. The logic is a bit complicated; by default, unicast 645 * packets will follow path MTU while multicast packets will be sent at 646 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets 647 * including unicast ones will be sent at the minimum MTU. Multicast 648 * packets will always be sent at the minimum MTU unless 649 * IP6PO_MINMTU_DISABLE is explicitly specified. 650 * See RFC 3542 for more details. 651 */ 652 if (mtu > IPV6_MMTU) { 653 if ((flags & IPV6_MINMTU)) 654 mtu = IPV6_MMTU; 655 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL) 656 mtu = IPV6_MMTU; 657 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 658 (opt == NULL || 659 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) { 660 mtu = IPV6_MMTU; 661 } 662 } 663 664 /* 665 * clear embedded scope identifiers if necessary. 666 * in6_clearscope will touch the addresses only when necessary. 667 */ 668 in6_clearscope(&ip6->ip6_src); 669 in6_clearscope(&ip6->ip6_dst); 670 671 /* 672 * If the outgoing packet contains a hop-by-hop options header, 673 * it must be examined and processed even by the source node. 674 * (RFC 2460, section 4.) 675 */ 676 if (ip6->ip6_nxt == IPV6_HOPOPTS) { 677 u_int32_t dummy1; /* XXX unused */ 678 u_int32_t dummy2; /* XXX unused */ 679 int hoff = sizeof(struct ip6_hdr); 680 681 if (ip6_hopopts_input(&dummy1, &dummy2, &m, &hoff)) { 682 /* m was already freed at this point */ 683 error = EINVAL;/* better error? */ 684 goto done; 685 } 686 687 ip6 = mtod(m, struct ip6_hdr *); 688 } 689 690 /* 691 * Run through list of hooks for output packets. 692 */ 693 if ((error = pfil_run_hooks(inet6_pfil_hook, &m, ifp, PFIL_OUT)) != 0) 694 goto done; 695 if (m == NULL) 696 goto done; 697 ip6 = mtod(m, struct ip6_hdr *); 698 699 /* 700 * Send the packet to the outgoing interface. 701 * If necessary, do IPv6 fragmentation before sending. 702 * 703 * the logic here is rather complex: 704 * 1: normal case (dontfrag == 0, alwaysfrag == 0) 705 * 1-a: send as is if tlen <= path mtu 706 * 1-b: fragment if tlen > path mtu 707 * 708 * 2: if user asks us not to fragment (dontfrag == 1) 709 * 2-a: send as is if tlen <= interface mtu 710 * 2-b: error if tlen > interface mtu 711 * 712 * 3: if we always need to attach fragment header (alwaysfrag == 1) 713 * always fragment 714 * 715 * 4: if dontfrag == 1 && alwaysfrag == 1 716 * error, as we cannot handle this conflicting request 717 */ 718 tlen = m->m_pkthdr.len; 719 tso = (m->m_pkthdr.csum_flags & M_CSUM_TSOv6) != 0; 720 if (opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) 721 dontfrag = 1; 722 else 723 dontfrag = 0; 724 725 if (dontfrag && alwaysfrag) { /* case 4 */ 726 /* conflicting request - can't transmit */ 727 error = EMSGSIZE; 728 goto bad; 729 } 730 if (dontfrag && (!tso && tlen > IN6_LINKMTU(ifp))) { /* case 2-b */ 731 /* 732 * Even if the DONTFRAG option is specified, we cannot send the 733 * packet when the data length is larger than the MTU of the 734 * outgoing interface. 735 * Notify the error by sending IPV6_PATHMTU ancillary data as 736 * well as returning an error code (the latter is not described 737 * in the API spec.) 738 */ 739 u_int32_t mtu32; 740 struct ip6ctlparam ip6cp; 741 742 mtu32 = (u_int32_t)mtu; 743 memset(&ip6cp, 0, sizeof(ip6cp)); 744 ip6cp.ip6c_cmdarg = (void *)&mtu32; 745 pfctlinput2(PRC_MSGSIZE, 746 rtcache_getdst(ro_pmtu), &ip6cp); 747 748 error = EMSGSIZE; 749 goto bad; 750 } 751 752 /* 753 * transmit packet without fragmentation 754 */ 755 if (dontfrag || (!alwaysfrag && (tlen <= mtu || tso))) { 756 /* case 1-a and 2-a */ 757 struct in6_ifaddr *ia6; 758 int sw_csum; 759 760 ip6 = mtod(m, struct ip6_hdr *); 761 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 762 if (ia6) { 763 /* Record statistics for this interface address. */ 764 ia6->ia_ifa.ifa_data.ifad_outbytes += m->m_pkthdr.len; 765 } 766 767 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 768 if ((sw_csum & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0) { 769 if (IN6_NEED_CHECKSUM(ifp, 770 sw_csum & (M_CSUM_UDPv6|M_CSUM_TCPv6))) { 771 in6_delayed_cksum(m); 772 } 773 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 774 } 775 776 KASSERT(dst != NULL); 777 if (__predict_true(!tso || 778 (ifp->if_capenable & IFCAP_TSOv6) != 0)) { 779 error = nd6_output(ifp, origifp, m, dst, rt); 780 } else { 781 error = ip6_tso_output(ifp, origifp, m, dst, rt); 782 } 783 goto done; 784 } 785 786 if (tso) { 787 error = EINVAL; /* XXX */ 788 goto bad; 789 } 790 791 /* 792 * try to fragment the packet. case 1-b and 3 793 */ 794 if (mtu < IPV6_MMTU) { 795 /* path MTU cannot be less than IPV6_MMTU */ 796 error = EMSGSIZE; 797 in6_ifstat_inc(ifp, ifs6_out_fragfail); 798 goto bad; 799 } else if (ip6->ip6_plen == 0) { 800 /* jumbo payload cannot be fragmented */ 801 error = EMSGSIZE; 802 in6_ifstat_inc(ifp, ifs6_out_fragfail); 803 goto bad; 804 } else { 805 struct mbuf **mnext, *m_frgpart; 806 struct ip6_frag *ip6f; 807 u_int32_t id = htonl(ip6_randomid()); 808 u_char nextproto; 809 #if 0 /* see below */ 810 struct ip6ctlparam ip6cp; 811 u_int32_t mtu32; 812 #endif 813 814 /* 815 * Too large for the destination or interface; 816 * fragment if possible. 817 * Must be able to put at least 8 bytes per fragment. 818 */ 819 hlen = unfragpartlen; 820 if (mtu > IPV6_MAXPACKET) 821 mtu = IPV6_MAXPACKET; 822 823 #if 0 824 /* 825 * It is believed this code is a leftover from the 826 * development of the IPV6_RECVPATHMTU sockopt and 827 * associated work to implement RFC3542. 828 * It's not entirely clear what the intent of the API 829 * is at this point, so disable this code for now. 830 * The IPV6_RECVPATHMTU sockopt and/or IPV6_DONTFRAG 831 * will send notifications if the application requests. 832 */ 833 834 /* Notify a proper path MTU to applications. */ 835 mtu32 = (u_int32_t)mtu; 836 memset(&ip6cp, 0, sizeof(ip6cp)); 837 ip6cp.ip6c_cmdarg = (void *)&mtu32; 838 pfctlinput2(PRC_MSGSIZE, 839 rtcache_getdst(ro_pmtu), &ip6cp); 840 #endif 841 842 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; 843 if (len < 8) { 844 error = EMSGSIZE; 845 in6_ifstat_inc(ifp, ifs6_out_fragfail); 846 goto bad; 847 } 848 849 mnext = &m->m_nextpkt; 850 851 /* 852 * Change the next header field of the last header in the 853 * unfragmentable part. 854 */ 855 if (exthdrs.ip6e_rthdr) { 856 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); 857 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; 858 } else if (exthdrs.ip6e_dest1) { 859 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); 860 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; 861 } else if (exthdrs.ip6e_hbh) { 862 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); 863 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; 864 } else { 865 nextproto = ip6->ip6_nxt; 866 ip6->ip6_nxt = IPPROTO_FRAGMENT; 867 } 868 869 if ((m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) 870 != 0) { 871 if (IN6_NEED_CHECKSUM(ifp, 872 m->m_pkthdr.csum_flags & 873 (M_CSUM_UDPv6|M_CSUM_TCPv6))) { 874 in6_delayed_cksum(m); 875 } 876 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 877 } 878 879 /* 880 * Loop through length of segment after first fragment, 881 * make new header and copy data of each part and link onto 882 * chain. 883 */ 884 m0 = m; 885 for (off = hlen; off < tlen; off += len) { 886 struct mbuf *mlast; 887 888 MGETHDR(m, M_DONTWAIT, MT_HEADER); 889 if (!m) { 890 error = ENOBUFS; 891 IP6_STATINC(IP6_STAT_ODROPPED); 892 goto sendorfree; 893 } 894 m->m_pkthdr.rcvif = NULL; 895 m->m_flags = m0->m_flags & M_COPYFLAGS; 896 *mnext = m; 897 mnext = &m->m_nextpkt; 898 m->m_data += max_linkhdr; 899 mhip6 = mtod(m, struct ip6_hdr *); 900 *mhip6 = *ip6; 901 m->m_len = sizeof(*mhip6); 902 /* 903 * ip6f must be valid if error is 0. But how 904 * can a compiler be expected to infer this? 905 */ 906 ip6f = NULL; 907 error = ip6_insertfraghdr(m0, m, hlen, &ip6f); 908 if (error) { 909 IP6_STATINC(IP6_STAT_ODROPPED); 910 goto sendorfree; 911 } 912 ip6f->ip6f_offlg = htons((u_int16_t)((off - hlen) & ~7)); 913 if (off + len >= tlen) 914 len = tlen - off; 915 else 916 ip6f->ip6f_offlg |= IP6F_MORE_FRAG; 917 mhip6->ip6_plen = htons((u_int16_t)(len + hlen + 918 sizeof(*ip6f) - sizeof(struct ip6_hdr))); 919 if ((m_frgpart = m_copy(m0, off, len)) == 0) { 920 error = ENOBUFS; 921 IP6_STATINC(IP6_STAT_ODROPPED); 922 goto sendorfree; 923 } 924 for (mlast = m; mlast->m_next; mlast = mlast->m_next) 925 ; 926 mlast->m_next = m_frgpart; 927 m->m_pkthdr.len = len + hlen + sizeof(*ip6f); 928 m->m_pkthdr.rcvif = NULL; 929 ip6f->ip6f_reserved = 0; 930 ip6f->ip6f_ident = id; 931 ip6f->ip6f_nxt = nextproto; 932 IP6_STATINC(IP6_STAT_OFRAGMENTS); 933 in6_ifstat_inc(ifp, ifs6_out_fragcreat); 934 } 935 936 in6_ifstat_inc(ifp, ifs6_out_fragok); 937 } 938 939 /* 940 * Remove leading garbages. 941 */ 942 sendorfree: 943 m = m0->m_nextpkt; 944 m0->m_nextpkt = 0; 945 m_freem(m0); 946 for (m0 = m; m; m = m0) { 947 m0 = m->m_nextpkt; 948 m->m_nextpkt = 0; 949 if (error == 0) { 950 struct in6_ifaddr *ia6; 951 ip6 = mtod(m, struct ip6_hdr *); 952 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 953 if (ia6) { 954 /* 955 * Record statistics for this interface 956 * address. 957 */ 958 ia6->ia_ifa.ifa_data.ifad_outbytes += 959 m->m_pkthdr.len; 960 } 961 KASSERT(dst != NULL); 962 error = nd6_output(ifp, origifp, m, dst, rt); 963 } else 964 m_freem(m); 965 } 966 967 if (error == 0) 968 IP6_STATINC(IP6_STAT_FRAGMENTED); 969 970 done: 971 rtcache_free(&ip6route); 972 973 #ifdef IPSEC 974 if (sp != NULL) 975 KEY_FREESP(&sp); 976 #endif /* IPSEC */ 977 978 979 return (error); 980 981 freehdrs: 982 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */ 983 m_freem(exthdrs.ip6e_dest1); 984 m_freem(exthdrs.ip6e_rthdr); 985 m_freem(exthdrs.ip6e_dest2); 986 /* FALLTHROUGH */ 987 bad: 988 m_freem(m); 989 goto done; 990 badscope: 991 IP6_STATINC(IP6_STAT_BADSCOPE); 992 in6_ifstat_inc(origifp, ifs6_out_discard); 993 if (error == 0) 994 error = EHOSTUNREACH; /* XXX */ 995 goto bad; 996 } 997 998 static int 999 ip6_copyexthdr(struct mbuf **mp, void *hdr, int hlen) 1000 { 1001 struct mbuf *m; 1002 1003 if (hlen > MCLBYTES) 1004 return (ENOBUFS); /* XXX */ 1005 1006 MGET(m, M_DONTWAIT, MT_DATA); 1007 if (!m) 1008 return (ENOBUFS); 1009 1010 if (hlen > MLEN) { 1011 MCLGET(m, M_DONTWAIT); 1012 if ((m->m_flags & M_EXT) == 0) { 1013 m_free(m); 1014 return (ENOBUFS); 1015 } 1016 } 1017 m->m_len = hlen; 1018 if (hdr) 1019 bcopy(hdr, mtod(m, void *), hlen); 1020 1021 *mp = m; 1022 return (0); 1023 } 1024 1025 /* 1026 * Process a delayed payload checksum calculation. 1027 */ 1028 void 1029 in6_delayed_cksum(struct mbuf *m) 1030 { 1031 uint16_t csum, offset; 1032 1033 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0); 1034 KASSERT((~m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0); 1035 KASSERT((m->m_pkthdr.csum_flags 1036 & (M_CSUM_UDPv4|M_CSUM_TCPv4|M_CSUM_TSOv4)) == 0); 1037 1038 offset = M_CSUM_DATA_IPv6_HL(m->m_pkthdr.csum_data); 1039 csum = in6_cksum(m, 0, offset, m->m_pkthdr.len - offset); 1040 if (csum == 0 && (m->m_pkthdr.csum_flags & M_CSUM_UDPv6) != 0) { 1041 csum = 0xffff; 1042 } 1043 1044 offset += M_CSUM_DATA_IPv6_OFFSET(m->m_pkthdr.csum_data); 1045 if ((offset + sizeof(csum)) > m->m_len) { 1046 m_copyback(m, offset, sizeof(csum), &csum); 1047 } else { 1048 *(uint16_t *)(mtod(m, char *) + offset) = csum; 1049 } 1050 } 1051 1052 /* 1053 * Insert jumbo payload option. 1054 */ 1055 static int 1056 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen) 1057 { 1058 struct mbuf *mopt; 1059 u_int8_t *optbuf; 1060 u_int32_t v; 1061 1062 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */ 1063 1064 /* 1065 * If there is no hop-by-hop options header, allocate new one. 1066 * If there is one but it doesn't have enough space to store the 1067 * jumbo payload option, allocate a cluster to store the whole options. 1068 * Otherwise, use it to store the options. 1069 */ 1070 if (exthdrs->ip6e_hbh == 0) { 1071 MGET(mopt, M_DONTWAIT, MT_DATA); 1072 if (mopt == 0) 1073 return (ENOBUFS); 1074 mopt->m_len = JUMBOOPTLEN; 1075 optbuf = mtod(mopt, u_int8_t *); 1076 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */ 1077 exthdrs->ip6e_hbh = mopt; 1078 } else { 1079 struct ip6_hbh *hbh; 1080 1081 mopt = exthdrs->ip6e_hbh; 1082 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) { 1083 /* 1084 * XXX assumption: 1085 * - exthdrs->ip6e_hbh is not referenced from places 1086 * other than exthdrs. 1087 * - exthdrs->ip6e_hbh is not an mbuf chain. 1088 */ 1089 int oldoptlen = mopt->m_len; 1090 struct mbuf *n; 1091 1092 /* 1093 * XXX: give up if the whole (new) hbh header does 1094 * not fit even in an mbuf cluster. 1095 */ 1096 if (oldoptlen + JUMBOOPTLEN > MCLBYTES) 1097 return (ENOBUFS); 1098 1099 /* 1100 * As a consequence, we must always prepare a cluster 1101 * at this point. 1102 */ 1103 MGET(n, M_DONTWAIT, MT_DATA); 1104 if (n) { 1105 MCLGET(n, M_DONTWAIT); 1106 if ((n->m_flags & M_EXT) == 0) { 1107 m_freem(n); 1108 n = NULL; 1109 } 1110 } 1111 if (!n) 1112 return (ENOBUFS); 1113 n->m_len = oldoptlen + JUMBOOPTLEN; 1114 bcopy(mtod(mopt, void *), mtod(n, void *), 1115 oldoptlen); 1116 optbuf = mtod(n, u_int8_t *) + oldoptlen; 1117 m_freem(mopt); 1118 mopt = exthdrs->ip6e_hbh = n; 1119 } else { 1120 optbuf = mtod(mopt, u_int8_t *) + mopt->m_len; 1121 mopt->m_len += JUMBOOPTLEN; 1122 } 1123 optbuf[0] = IP6OPT_PADN; 1124 optbuf[1] = 0; 1125 1126 /* 1127 * Adjust the header length according to the pad and 1128 * the jumbo payload option. 1129 */ 1130 hbh = mtod(mopt, struct ip6_hbh *); 1131 hbh->ip6h_len += (JUMBOOPTLEN >> 3); 1132 } 1133 1134 /* fill in the option. */ 1135 optbuf[2] = IP6OPT_JUMBO; 1136 optbuf[3] = 4; 1137 v = (u_int32_t)htonl(plen + JUMBOOPTLEN); 1138 bcopy(&v, &optbuf[4], sizeof(u_int32_t)); 1139 1140 /* finally, adjust the packet header length */ 1141 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN; 1142 1143 return (0); 1144 #undef JUMBOOPTLEN 1145 } 1146 1147 /* 1148 * Insert fragment header and copy unfragmentable header portions. 1149 * 1150 * *frghdrp will not be read, and it is guaranteed that either an 1151 * error is returned or that *frghdrp will point to space allocated 1152 * for the fragment header. 1153 */ 1154 static int 1155 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen, 1156 struct ip6_frag **frghdrp) 1157 { 1158 struct mbuf *n, *mlast; 1159 1160 if (hlen > sizeof(struct ip6_hdr)) { 1161 n = m_copym(m0, sizeof(struct ip6_hdr), 1162 hlen - sizeof(struct ip6_hdr), M_DONTWAIT); 1163 if (n == 0) 1164 return (ENOBUFS); 1165 m->m_next = n; 1166 } else 1167 n = m; 1168 1169 /* Search for the last mbuf of unfragmentable part. */ 1170 for (mlast = n; mlast->m_next; mlast = mlast->m_next) 1171 ; 1172 1173 if ((mlast->m_flags & M_EXT) == 0 && 1174 M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) { 1175 /* use the trailing space of the last mbuf for the fragment hdr */ 1176 *frghdrp = (struct ip6_frag *)(mtod(mlast, char *) + 1177 mlast->m_len); 1178 mlast->m_len += sizeof(struct ip6_frag); 1179 m->m_pkthdr.len += sizeof(struct ip6_frag); 1180 } else { 1181 /* allocate a new mbuf for the fragment header */ 1182 struct mbuf *mfrg; 1183 1184 MGET(mfrg, M_DONTWAIT, MT_DATA); 1185 if (mfrg == 0) 1186 return (ENOBUFS); 1187 mfrg->m_len = sizeof(struct ip6_frag); 1188 *frghdrp = mtod(mfrg, struct ip6_frag *); 1189 mlast->m_next = mfrg; 1190 } 1191 1192 return (0); 1193 } 1194 1195 static int 1196 ip6_getpmtu(struct route *ro_pmtu, struct route *ro, struct ifnet *ifp, 1197 const struct in6_addr *dst, u_long *mtup, int *alwaysfragp) 1198 { 1199 struct rtentry *rt; 1200 u_int32_t mtu = 0; 1201 int alwaysfrag = 0; 1202 int error = 0; 1203 1204 if (ro_pmtu != ro) { 1205 union { 1206 struct sockaddr dst; 1207 struct sockaddr_in6 dst6; 1208 } u; 1209 1210 /* The first hop and the final destination may differ. */ 1211 sockaddr_in6_init(&u.dst6, dst, 0, 0, 0); 1212 rt = rtcache_lookup(ro_pmtu, &u.dst); 1213 } else 1214 rt = rtcache_validate(ro_pmtu); 1215 if (rt != NULL) { 1216 u_int32_t ifmtu; 1217 1218 if (ifp == NULL) 1219 ifp = rt->rt_ifp; 1220 ifmtu = IN6_LINKMTU(ifp); 1221 mtu = rt->rt_rmx.rmx_mtu; 1222 if (mtu == 0) 1223 mtu = ifmtu; 1224 else if (mtu < IPV6_MMTU) { 1225 /* 1226 * RFC2460 section 5, last paragraph: 1227 * if we record ICMPv6 too big message with 1228 * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU 1229 * or smaller, with fragment header attached. 1230 * (fragment header is needed regardless from the 1231 * packet size, for translators to identify packets) 1232 */ 1233 alwaysfrag = 1; 1234 mtu = IPV6_MMTU; 1235 } else if (mtu > ifmtu) { 1236 /* 1237 * The MTU on the route is larger than the MTU on 1238 * the interface! This shouldn't happen, unless the 1239 * MTU of the interface has been changed after the 1240 * interface was brought up. Change the MTU in the 1241 * route to match the interface MTU (as long as the 1242 * field isn't locked). 1243 */ 1244 mtu = ifmtu; 1245 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 1246 rt->rt_rmx.rmx_mtu = mtu; 1247 } 1248 } else if (ifp) { 1249 mtu = IN6_LINKMTU(ifp); 1250 } else 1251 error = EHOSTUNREACH; /* XXX */ 1252 1253 *mtup = mtu; 1254 if (alwaysfragp) 1255 *alwaysfragp = alwaysfrag; 1256 return (error); 1257 } 1258 1259 /* 1260 * IP6 socket option processing. 1261 */ 1262 int 1263 ip6_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1264 { 1265 int optdatalen, uproto; 1266 void *optdata; 1267 struct in6pcb *in6p = sotoin6pcb(so); 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 if (level != IPPROTO_IPV6) { 1280 return ENOPROTOOPT; 1281 } 1282 switch (op) { 1283 case PRCO_SETOPT: 1284 switch (optname) { 1285 #ifdef RFC2292 1286 case IPV6_2292PKTOPTIONS: 1287 error = ip6_pcbopts(&in6p->in6p_outputopts, so, sopt); 1288 break; 1289 #endif 1290 1291 /* 1292 * Use of some Hop-by-Hop options or some 1293 * Destination options, might require special 1294 * privilege. That is, normal applications 1295 * (without special privilege) might be forbidden 1296 * from setting certain options in outgoing packets, 1297 * and might never see certain options in received 1298 * packets. [RFC 2292 Section 6] 1299 * KAME specific note: 1300 * KAME prevents non-privileged users from sending or 1301 * receiving ANY hbh/dst options in order to avoid 1302 * overhead of parsing options in the kernel. 1303 */ 1304 case IPV6_RECVHOPOPTS: 1305 case IPV6_RECVDSTOPTS: 1306 case IPV6_RECVRTHDRDSTOPTS: 1307 error = kauth_authorize_network(kauth_cred_get(), 1308 KAUTH_NETWORK_IPV6, KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, 1309 NULL, NULL, NULL); 1310 if (error) 1311 break; 1312 /* FALLTHROUGH */ 1313 case IPV6_UNICAST_HOPS: 1314 case IPV6_HOPLIMIT: 1315 case IPV6_FAITH: 1316 1317 case IPV6_RECVPKTINFO: 1318 case IPV6_RECVHOPLIMIT: 1319 case IPV6_RECVRTHDR: 1320 case IPV6_RECVPATHMTU: 1321 case IPV6_RECVTCLASS: 1322 case IPV6_V6ONLY: 1323 error = sockopt_getint(sopt, &optval); 1324 if (error) 1325 break; 1326 switch (optname) { 1327 case IPV6_UNICAST_HOPS: 1328 if (optval < -1 || optval >= 256) 1329 error = EINVAL; 1330 else { 1331 /* -1 = kernel default */ 1332 in6p->in6p_hops = optval; 1333 } 1334 break; 1335 #define OPTSET(bit) \ 1336 do { \ 1337 if (optval) \ 1338 in6p->in6p_flags |= (bit); \ 1339 else \ 1340 in6p->in6p_flags &= ~(bit); \ 1341 } while (/*CONSTCOND*/ 0) 1342 1343 #ifdef RFC2292 1344 #define OPTSET2292(bit) \ 1345 do { \ 1346 in6p->in6p_flags |= IN6P_RFC2292; \ 1347 if (optval) \ 1348 in6p->in6p_flags |= (bit); \ 1349 else \ 1350 in6p->in6p_flags &= ~(bit); \ 1351 } while (/*CONSTCOND*/ 0) 1352 #endif 1353 1354 #define OPTBIT(bit) (in6p->in6p_flags & (bit) ? 1 : 0) 1355 1356 case IPV6_RECVPKTINFO: 1357 #ifdef RFC2292 1358 /* cannot mix with RFC2292 */ 1359 if (OPTBIT(IN6P_RFC2292)) { 1360 error = EINVAL; 1361 break; 1362 } 1363 #endif 1364 OPTSET(IN6P_PKTINFO); 1365 break; 1366 1367 case IPV6_HOPLIMIT: 1368 { 1369 struct ip6_pktopts **optp; 1370 1371 #ifdef RFC2292 1372 /* cannot mix with RFC2292 */ 1373 if (OPTBIT(IN6P_RFC2292)) { 1374 error = EINVAL; 1375 break; 1376 } 1377 #endif 1378 optp = &in6p->in6p_outputopts; 1379 error = ip6_pcbopt(IPV6_HOPLIMIT, 1380 (u_char *)&optval, 1381 sizeof(optval), 1382 optp, 1383 kauth_cred_get(), uproto); 1384 break; 1385 } 1386 1387 case IPV6_RECVHOPLIMIT: 1388 #ifdef RFC2292 1389 /* cannot mix with RFC2292 */ 1390 if (OPTBIT(IN6P_RFC2292)) { 1391 error = EINVAL; 1392 break; 1393 } 1394 #endif 1395 OPTSET(IN6P_HOPLIMIT); 1396 break; 1397 1398 case IPV6_RECVHOPOPTS: 1399 #ifdef RFC2292 1400 /* cannot mix with RFC2292 */ 1401 if (OPTBIT(IN6P_RFC2292)) { 1402 error = EINVAL; 1403 break; 1404 } 1405 #endif 1406 OPTSET(IN6P_HOPOPTS); 1407 break; 1408 1409 case IPV6_RECVDSTOPTS: 1410 #ifdef RFC2292 1411 /* cannot mix with RFC2292 */ 1412 if (OPTBIT(IN6P_RFC2292)) { 1413 error = EINVAL; 1414 break; 1415 } 1416 #endif 1417 OPTSET(IN6P_DSTOPTS); 1418 break; 1419 1420 case IPV6_RECVRTHDRDSTOPTS: 1421 #ifdef RFC2292 1422 /* cannot mix with RFC2292 */ 1423 if (OPTBIT(IN6P_RFC2292)) { 1424 error = EINVAL; 1425 break; 1426 } 1427 #endif 1428 OPTSET(IN6P_RTHDRDSTOPTS); 1429 break; 1430 1431 case IPV6_RECVRTHDR: 1432 #ifdef RFC2292 1433 /* cannot mix with RFC2292 */ 1434 if (OPTBIT(IN6P_RFC2292)) { 1435 error = EINVAL; 1436 break; 1437 } 1438 #endif 1439 OPTSET(IN6P_RTHDR); 1440 break; 1441 1442 case IPV6_FAITH: 1443 OPTSET(IN6P_FAITH); 1444 break; 1445 1446 case IPV6_RECVPATHMTU: 1447 /* 1448 * We ignore this option for TCP 1449 * sockets. 1450 * (RFC3542 leaves this case 1451 * unspecified.) 1452 */ 1453 if (uproto != IPPROTO_TCP) 1454 OPTSET(IN6P_MTU); 1455 break; 1456 1457 case IPV6_V6ONLY: 1458 /* 1459 * make setsockopt(IPV6_V6ONLY) 1460 * available only prior to bind(2). 1461 * see ipng mailing list, Jun 22 2001. 1462 */ 1463 if (in6p->in6p_lport || 1464 !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) { 1465 error = EINVAL; 1466 break; 1467 } 1468 #ifdef INET6_BINDV6ONLY 1469 if (!optval) 1470 error = EINVAL; 1471 #else 1472 OPTSET(IN6P_IPV6_V6ONLY); 1473 #endif 1474 break; 1475 case IPV6_RECVTCLASS: 1476 #ifdef RFC2292 1477 /* cannot mix with RFC2292 XXX */ 1478 if (OPTBIT(IN6P_RFC2292)) { 1479 error = EINVAL; 1480 break; 1481 } 1482 #endif 1483 OPTSET(IN6P_TCLASS); 1484 break; 1485 1486 } 1487 break; 1488 1489 case IPV6_OTCLASS: 1490 { 1491 struct ip6_pktopts **optp; 1492 u_int8_t tclass; 1493 1494 error = sockopt_get(sopt, &tclass, sizeof(tclass)); 1495 if (error) 1496 break; 1497 optp = &in6p->in6p_outputopts; 1498 error = ip6_pcbopt(optname, 1499 (u_char *)&tclass, 1500 sizeof(tclass), 1501 optp, 1502 kauth_cred_get(), uproto); 1503 break; 1504 } 1505 1506 case IPV6_TCLASS: 1507 case IPV6_DONTFRAG: 1508 case IPV6_USE_MIN_MTU: 1509 error = sockopt_getint(sopt, &optval); 1510 if (error) 1511 break; 1512 { 1513 struct ip6_pktopts **optp; 1514 optp = &in6p->in6p_outputopts; 1515 error = ip6_pcbopt(optname, 1516 (u_char *)&optval, 1517 sizeof(optval), 1518 optp, 1519 kauth_cred_get(), uproto); 1520 break; 1521 } 1522 1523 #ifdef RFC2292 1524 case IPV6_2292PKTINFO: 1525 case IPV6_2292HOPLIMIT: 1526 case IPV6_2292HOPOPTS: 1527 case IPV6_2292DSTOPTS: 1528 case IPV6_2292RTHDR: 1529 /* RFC 2292 */ 1530 error = sockopt_getint(sopt, &optval); 1531 if (error) 1532 break; 1533 1534 switch (optname) { 1535 case IPV6_2292PKTINFO: 1536 OPTSET2292(IN6P_PKTINFO); 1537 break; 1538 case IPV6_2292HOPLIMIT: 1539 OPTSET2292(IN6P_HOPLIMIT); 1540 break; 1541 case IPV6_2292HOPOPTS: 1542 /* 1543 * Check super-user privilege. 1544 * See comments for IPV6_RECVHOPOPTS. 1545 */ 1546 error = 1547 kauth_authorize_network(kauth_cred_get(), 1548 KAUTH_NETWORK_IPV6, 1549 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, 1550 NULL, NULL); 1551 if (error) 1552 return (error); 1553 OPTSET2292(IN6P_HOPOPTS); 1554 break; 1555 case IPV6_2292DSTOPTS: 1556 error = 1557 kauth_authorize_network(kauth_cred_get(), 1558 KAUTH_NETWORK_IPV6, 1559 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, 1560 NULL, NULL); 1561 if (error) 1562 return (error); 1563 OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */ 1564 break; 1565 case IPV6_2292RTHDR: 1566 OPTSET2292(IN6P_RTHDR); 1567 break; 1568 } 1569 break; 1570 #endif 1571 case IPV6_PKTINFO: 1572 case IPV6_HOPOPTS: 1573 case IPV6_RTHDR: 1574 case IPV6_DSTOPTS: 1575 case IPV6_RTHDRDSTOPTS: 1576 case IPV6_NEXTHOP: { 1577 /* new advanced API (RFC3542) */ 1578 void *optbuf; 1579 int optbuflen; 1580 struct ip6_pktopts **optp; 1581 1582 #ifdef RFC2292 1583 /* cannot mix with RFC2292 */ 1584 if (OPTBIT(IN6P_RFC2292)) { 1585 error = EINVAL; 1586 break; 1587 } 1588 #endif 1589 1590 optbuflen = sopt->sopt_size; 1591 optbuf = malloc(optbuflen, M_IP6OPT, M_NOWAIT); 1592 if (optbuf == NULL) { 1593 error = ENOBUFS; 1594 break; 1595 } 1596 1597 error = sockopt_get(sopt, optbuf, optbuflen); 1598 if (error) { 1599 free(optbuf, M_IP6OPT); 1600 break; 1601 } 1602 optp = &in6p->in6p_outputopts; 1603 error = ip6_pcbopt(optname, optbuf, optbuflen, 1604 optp, kauth_cred_get(), uproto); 1605 break; 1606 } 1607 #undef OPTSET 1608 1609 case IPV6_MULTICAST_IF: 1610 case IPV6_MULTICAST_HOPS: 1611 case IPV6_MULTICAST_LOOP: 1612 case IPV6_JOIN_GROUP: 1613 case IPV6_LEAVE_GROUP: 1614 error = ip6_setmoptions(sopt, &in6p->in6p_moptions); 1615 break; 1616 1617 case IPV6_PORTRANGE: 1618 error = sockopt_getint(sopt, &optval); 1619 if (error) 1620 break; 1621 1622 switch (optval) { 1623 case IPV6_PORTRANGE_DEFAULT: 1624 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1625 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1626 break; 1627 1628 case IPV6_PORTRANGE_HIGH: 1629 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1630 in6p->in6p_flags |= IN6P_HIGHPORT; 1631 break; 1632 1633 case IPV6_PORTRANGE_LOW: 1634 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1635 in6p->in6p_flags |= IN6P_LOWPORT; 1636 break; 1637 1638 default: 1639 error = EINVAL; 1640 break; 1641 } 1642 break; 1643 1644 case IPV6_PORTALGO: 1645 error = sockopt_getint(sopt, &optval); 1646 if (error) 1647 break; 1648 1649 error = portalgo_algo_index_select( 1650 (struct inpcb_hdr *)in6p, optval); 1651 break; 1652 1653 #if defined(IPSEC) 1654 case IPV6_IPSEC_POLICY: 1655 error = ipsec6_set_policy(in6p, optname, 1656 sopt->sopt_data, sopt->sopt_size, kauth_cred_get()); 1657 break; 1658 #endif /* IPSEC */ 1659 1660 default: 1661 error = ENOPROTOOPT; 1662 break; 1663 } 1664 break; 1665 1666 case PRCO_GETOPT: 1667 switch (optname) { 1668 #ifdef RFC2292 1669 case IPV6_2292PKTOPTIONS: 1670 /* 1671 * RFC3542 (effectively) deprecated the 1672 * semantics of the 2292-style pktoptions. 1673 * Since it was not reliable in nature (i.e., 1674 * applications had to expect the lack of some 1675 * information after all), it would make sense 1676 * to simplify this part by always returning 1677 * empty data. 1678 */ 1679 break; 1680 #endif 1681 1682 case IPV6_RECVHOPOPTS: 1683 case IPV6_RECVDSTOPTS: 1684 case IPV6_RECVRTHDRDSTOPTS: 1685 case IPV6_UNICAST_HOPS: 1686 case IPV6_RECVPKTINFO: 1687 case IPV6_RECVHOPLIMIT: 1688 case IPV6_RECVRTHDR: 1689 case IPV6_RECVPATHMTU: 1690 1691 case IPV6_FAITH: 1692 case IPV6_V6ONLY: 1693 case IPV6_PORTRANGE: 1694 case IPV6_RECVTCLASS: 1695 switch (optname) { 1696 1697 case IPV6_RECVHOPOPTS: 1698 optval = OPTBIT(IN6P_HOPOPTS); 1699 break; 1700 1701 case IPV6_RECVDSTOPTS: 1702 optval = OPTBIT(IN6P_DSTOPTS); 1703 break; 1704 1705 case IPV6_RECVRTHDRDSTOPTS: 1706 optval = OPTBIT(IN6P_RTHDRDSTOPTS); 1707 break; 1708 1709 case IPV6_UNICAST_HOPS: 1710 optval = in6p->in6p_hops; 1711 break; 1712 1713 case IPV6_RECVPKTINFO: 1714 optval = OPTBIT(IN6P_PKTINFO); 1715 break; 1716 1717 case IPV6_RECVHOPLIMIT: 1718 optval = OPTBIT(IN6P_HOPLIMIT); 1719 break; 1720 1721 case IPV6_RECVRTHDR: 1722 optval = OPTBIT(IN6P_RTHDR); 1723 break; 1724 1725 case IPV6_RECVPATHMTU: 1726 optval = OPTBIT(IN6P_MTU); 1727 break; 1728 1729 case IPV6_FAITH: 1730 optval = OPTBIT(IN6P_FAITH); 1731 break; 1732 1733 case IPV6_V6ONLY: 1734 optval = OPTBIT(IN6P_IPV6_V6ONLY); 1735 break; 1736 1737 case IPV6_PORTRANGE: 1738 { 1739 int flags; 1740 flags = in6p->in6p_flags; 1741 if (flags & IN6P_HIGHPORT) 1742 optval = IPV6_PORTRANGE_HIGH; 1743 else if (flags & IN6P_LOWPORT) 1744 optval = IPV6_PORTRANGE_LOW; 1745 else 1746 optval = 0; 1747 break; 1748 } 1749 case IPV6_RECVTCLASS: 1750 optval = OPTBIT(IN6P_TCLASS); 1751 break; 1752 1753 } 1754 if (error) 1755 break; 1756 error = sockopt_setint(sopt, optval); 1757 break; 1758 1759 case IPV6_PATHMTU: 1760 { 1761 u_long pmtu = 0; 1762 struct ip6_mtuinfo mtuinfo; 1763 struct route *ro = &in6p->in6p_route; 1764 1765 if (!(so->so_state & SS_ISCONNECTED)) 1766 return (ENOTCONN); 1767 /* 1768 * XXX: we dot not consider the case of source 1769 * routing, or optional information to specify 1770 * the outgoing interface. 1771 */ 1772 error = ip6_getpmtu(ro, NULL, NULL, 1773 &in6p->in6p_faddr, &pmtu, NULL); 1774 if (error) 1775 break; 1776 if (pmtu > IPV6_MAXPACKET) 1777 pmtu = IPV6_MAXPACKET; 1778 1779 memset(&mtuinfo, 0, sizeof(mtuinfo)); 1780 mtuinfo.ip6m_mtu = (u_int32_t)pmtu; 1781 optdata = (void *)&mtuinfo; 1782 optdatalen = sizeof(mtuinfo); 1783 if (optdatalen > MCLBYTES) 1784 return (EMSGSIZE); /* XXX */ 1785 error = sockopt_set(sopt, optdata, optdatalen); 1786 break; 1787 } 1788 1789 #ifdef RFC2292 1790 case IPV6_2292PKTINFO: 1791 case IPV6_2292HOPLIMIT: 1792 case IPV6_2292HOPOPTS: 1793 case IPV6_2292RTHDR: 1794 case IPV6_2292DSTOPTS: 1795 switch (optname) { 1796 case IPV6_2292PKTINFO: 1797 optval = OPTBIT(IN6P_PKTINFO); 1798 break; 1799 case IPV6_2292HOPLIMIT: 1800 optval = OPTBIT(IN6P_HOPLIMIT); 1801 break; 1802 case IPV6_2292HOPOPTS: 1803 optval = OPTBIT(IN6P_HOPOPTS); 1804 break; 1805 case IPV6_2292RTHDR: 1806 optval = OPTBIT(IN6P_RTHDR); 1807 break; 1808 case IPV6_2292DSTOPTS: 1809 optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); 1810 break; 1811 } 1812 error = sockopt_setint(sopt, optval); 1813 break; 1814 #endif 1815 case IPV6_PKTINFO: 1816 case IPV6_HOPOPTS: 1817 case IPV6_RTHDR: 1818 case IPV6_DSTOPTS: 1819 case IPV6_RTHDRDSTOPTS: 1820 case IPV6_NEXTHOP: 1821 case IPV6_OTCLASS: 1822 case IPV6_TCLASS: 1823 case IPV6_DONTFRAG: 1824 case IPV6_USE_MIN_MTU: 1825 error = ip6_getpcbopt(in6p->in6p_outputopts, 1826 optname, sopt); 1827 break; 1828 1829 case IPV6_MULTICAST_IF: 1830 case IPV6_MULTICAST_HOPS: 1831 case IPV6_MULTICAST_LOOP: 1832 case IPV6_JOIN_GROUP: 1833 case IPV6_LEAVE_GROUP: 1834 error = ip6_getmoptions(sopt, in6p->in6p_moptions); 1835 break; 1836 1837 case IPV6_PORTALGO: 1838 optval = ((struct inpcb_hdr *)in6p)->inph_portalgo; 1839 error = sockopt_setint(sopt, optval); 1840 break; 1841 1842 #if defined(IPSEC) 1843 case IPV6_IPSEC_POLICY: 1844 { 1845 struct mbuf *m = NULL; 1846 1847 /* XXX this will return EINVAL as sopt is empty */ 1848 error = ipsec6_get_policy(in6p, sopt->sopt_data, 1849 sopt->sopt_size, &m); 1850 if (!error) 1851 error = sockopt_setmbuf(sopt, m); 1852 1853 break; 1854 } 1855 #endif /* IPSEC */ 1856 1857 default: 1858 error = ENOPROTOOPT; 1859 break; 1860 } 1861 break; 1862 } 1863 return (error); 1864 } 1865 1866 int 1867 ip6_raw_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1868 { 1869 int error = 0, optval; 1870 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); 1871 struct in6pcb *in6p = sotoin6pcb(so); 1872 int level, optname; 1873 1874 KASSERT(sopt != NULL); 1875 1876 level = sopt->sopt_level; 1877 optname = sopt->sopt_name; 1878 1879 if (level != IPPROTO_IPV6) { 1880 return ENOPROTOOPT; 1881 } 1882 1883 switch (optname) { 1884 case IPV6_CHECKSUM: 1885 /* 1886 * For ICMPv6 sockets, no modification allowed for checksum 1887 * offset, permit "no change" values to help existing apps. 1888 * 1889 * XXX RFC3542 says: "An attempt to set IPV6_CHECKSUM 1890 * for an ICMPv6 socket will fail." The current 1891 * behavior does not meet RFC3542. 1892 */ 1893 switch (op) { 1894 case PRCO_SETOPT: 1895 error = sockopt_getint(sopt, &optval); 1896 if (error) 1897 break; 1898 if ((optval % 2) != 0) { 1899 /* the API assumes even offset values */ 1900 error = EINVAL; 1901 } else if (so->so_proto->pr_protocol == 1902 IPPROTO_ICMPV6) { 1903 if (optval != icmp6off) 1904 error = EINVAL; 1905 } else 1906 in6p->in6p_cksum = optval; 1907 break; 1908 1909 case PRCO_GETOPT: 1910 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) 1911 optval = icmp6off; 1912 else 1913 optval = in6p->in6p_cksum; 1914 1915 error = sockopt_setint(sopt, optval); 1916 break; 1917 1918 default: 1919 error = EINVAL; 1920 break; 1921 } 1922 break; 1923 1924 default: 1925 error = ENOPROTOOPT; 1926 break; 1927 } 1928 1929 return (error); 1930 } 1931 1932 #ifdef RFC2292 1933 /* 1934 * Set up IP6 options in pcb for insertion in output packets or 1935 * specifying behavior of outgoing packets. 1936 */ 1937 static int 1938 ip6_pcbopts(struct ip6_pktopts **pktopt, struct socket *so, 1939 struct sockopt *sopt) 1940 { 1941 struct ip6_pktopts *opt = *pktopt; 1942 struct mbuf *m; 1943 int error = 0; 1944 1945 /* turn off any old options. */ 1946 if (opt) { 1947 #ifdef DIAGNOSTIC 1948 if (opt->ip6po_pktinfo || opt->ip6po_nexthop || 1949 opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 || 1950 opt->ip6po_rhinfo.ip6po_rhi_rthdr) 1951 printf("ip6_pcbopts: all specified options are cleared.\n"); 1952 #endif 1953 ip6_clearpktopts(opt, -1); 1954 } else { 1955 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT); 1956 if (opt == NULL) 1957 return (ENOBUFS); 1958 } 1959 *pktopt = NULL; 1960 1961 if (sopt == NULL || sopt->sopt_size == 0) { 1962 /* 1963 * Only turning off any previous options, regardless of 1964 * whether the opt is just created or given. 1965 */ 1966 free(opt, M_IP6OPT); 1967 return (0); 1968 } 1969 1970 /* set options specified by user. */ 1971 m = sockopt_getmbuf(sopt); 1972 if (m == NULL) { 1973 free(opt, M_IP6OPT); 1974 return (ENOBUFS); 1975 } 1976 1977 error = ip6_setpktopts(m, opt, NULL, kauth_cred_get(), 1978 so->so_proto->pr_protocol); 1979 m_freem(m); 1980 if (error != 0) { 1981 ip6_clearpktopts(opt, -1); /* XXX: discard all options */ 1982 free(opt, M_IP6OPT); 1983 return (error); 1984 } 1985 *pktopt = opt; 1986 return (0); 1987 } 1988 #endif 1989 1990 /* 1991 * initialize ip6_pktopts. beware that there are non-zero default values in 1992 * the struct. 1993 */ 1994 void 1995 ip6_initpktopts(struct ip6_pktopts *opt) 1996 { 1997 1998 memset(opt, 0, sizeof(*opt)); 1999 opt->ip6po_hlim = -1; /* -1 means default hop limit */ 2000 opt->ip6po_tclass = -1; /* -1 means default traffic class */ 2001 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY; 2002 } 2003 2004 #define sin6tosa(sin6) ((struct sockaddr *)(sin6)) /* XXX */ 2005 static int 2006 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt, 2007 kauth_cred_t cred, int uproto) 2008 { 2009 struct ip6_pktopts *opt; 2010 2011 if (*pktopt == NULL) { 2012 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT, 2013 M_NOWAIT); 2014 if (*pktopt == NULL) 2015 return (ENOBUFS); 2016 2017 ip6_initpktopts(*pktopt); 2018 } 2019 opt = *pktopt; 2020 2021 return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto)); 2022 } 2023 2024 static int 2025 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt) 2026 { 2027 void *optdata = NULL; 2028 int optdatalen = 0; 2029 struct ip6_ext *ip6e; 2030 int error = 0; 2031 struct in6_pktinfo null_pktinfo; 2032 int deftclass = 0, on; 2033 int defminmtu = IP6PO_MINMTU_MCASTONLY; 2034 2035 switch (optname) { 2036 case IPV6_PKTINFO: 2037 if (pktopt && pktopt->ip6po_pktinfo) 2038 optdata = (void *)pktopt->ip6po_pktinfo; 2039 else { 2040 /* XXX: we don't have to do this every time... */ 2041 memset(&null_pktinfo, 0, sizeof(null_pktinfo)); 2042 optdata = (void *)&null_pktinfo; 2043 } 2044 optdatalen = sizeof(struct in6_pktinfo); 2045 break; 2046 case IPV6_OTCLASS: 2047 /* XXX */ 2048 return (EINVAL); 2049 case IPV6_TCLASS: 2050 if (pktopt && pktopt->ip6po_tclass >= 0) 2051 optdata = (void *)&pktopt->ip6po_tclass; 2052 else 2053 optdata = (void *)&deftclass; 2054 optdatalen = sizeof(int); 2055 break; 2056 case IPV6_HOPOPTS: 2057 if (pktopt && pktopt->ip6po_hbh) { 2058 optdata = (void *)pktopt->ip6po_hbh; 2059 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh; 2060 optdatalen = (ip6e->ip6e_len + 1) << 3; 2061 } 2062 break; 2063 case IPV6_RTHDR: 2064 if (pktopt && pktopt->ip6po_rthdr) { 2065 optdata = (void *)pktopt->ip6po_rthdr; 2066 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr; 2067 optdatalen = (ip6e->ip6e_len + 1) << 3; 2068 } 2069 break; 2070 case IPV6_RTHDRDSTOPTS: 2071 if (pktopt && pktopt->ip6po_dest1) { 2072 optdata = (void *)pktopt->ip6po_dest1; 2073 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1; 2074 optdatalen = (ip6e->ip6e_len + 1) << 3; 2075 } 2076 break; 2077 case IPV6_DSTOPTS: 2078 if (pktopt && pktopt->ip6po_dest2) { 2079 optdata = (void *)pktopt->ip6po_dest2; 2080 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2; 2081 optdatalen = (ip6e->ip6e_len + 1) << 3; 2082 } 2083 break; 2084 case IPV6_NEXTHOP: 2085 if (pktopt && pktopt->ip6po_nexthop) { 2086 optdata = (void *)pktopt->ip6po_nexthop; 2087 optdatalen = pktopt->ip6po_nexthop->sa_len; 2088 } 2089 break; 2090 case IPV6_USE_MIN_MTU: 2091 if (pktopt) 2092 optdata = (void *)&pktopt->ip6po_minmtu; 2093 else 2094 optdata = (void *)&defminmtu; 2095 optdatalen = sizeof(int); 2096 break; 2097 case IPV6_DONTFRAG: 2098 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG)) 2099 on = 1; 2100 else 2101 on = 0; 2102 optdata = (void *)&on; 2103 optdatalen = sizeof(on); 2104 break; 2105 default: /* should not happen */ 2106 #ifdef DIAGNOSTIC 2107 panic("ip6_getpcbopt: unexpected option\n"); 2108 #endif 2109 return (ENOPROTOOPT); 2110 } 2111 2112 error = sockopt_set(sopt, optdata, optdatalen); 2113 2114 return (error); 2115 } 2116 2117 void 2118 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname) 2119 { 2120 if (optname == -1 || optname == IPV6_PKTINFO) { 2121 if (pktopt->ip6po_pktinfo) 2122 free(pktopt->ip6po_pktinfo, M_IP6OPT); 2123 pktopt->ip6po_pktinfo = NULL; 2124 } 2125 if (optname == -1 || optname == IPV6_HOPLIMIT) 2126 pktopt->ip6po_hlim = -1; 2127 if (optname == -1 || optname == IPV6_TCLASS) 2128 pktopt->ip6po_tclass = -1; 2129 if (optname == -1 || optname == IPV6_NEXTHOP) { 2130 rtcache_free(&pktopt->ip6po_nextroute); 2131 if (pktopt->ip6po_nexthop) 2132 free(pktopt->ip6po_nexthop, M_IP6OPT); 2133 pktopt->ip6po_nexthop = NULL; 2134 } 2135 if (optname == -1 || optname == IPV6_HOPOPTS) { 2136 if (pktopt->ip6po_hbh) 2137 free(pktopt->ip6po_hbh, M_IP6OPT); 2138 pktopt->ip6po_hbh = NULL; 2139 } 2140 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) { 2141 if (pktopt->ip6po_dest1) 2142 free(pktopt->ip6po_dest1, M_IP6OPT); 2143 pktopt->ip6po_dest1 = NULL; 2144 } 2145 if (optname == -1 || optname == IPV6_RTHDR) { 2146 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr) 2147 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT); 2148 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL; 2149 rtcache_free(&pktopt->ip6po_route); 2150 } 2151 if (optname == -1 || optname == IPV6_DSTOPTS) { 2152 if (pktopt->ip6po_dest2) 2153 free(pktopt->ip6po_dest2, M_IP6OPT); 2154 pktopt->ip6po_dest2 = NULL; 2155 } 2156 } 2157 2158 #define PKTOPT_EXTHDRCPY(type) \ 2159 do { \ 2160 if (src->type) { \ 2161 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\ 2162 dst->type = malloc(hlen, M_IP6OPT, canwait); \ 2163 if (dst->type == NULL) \ 2164 goto bad; \ 2165 memcpy(dst->type, src->type, hlen); \ 2166 } \ 2167 } while (/*CONSTCOND*/ 0) 2168 2169 static int 2170 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait) 2171 { 2172 dst->ip6po_hlim = src->ip6po_hlim; 2173 dst->ip6po_tclass = src->ip6po_tclass; 2174 dst->ip6po_flags = src->ip6po_flags; 2175 if (src->ip6po_pktinfo) { 2176 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo), 2177 M_IP6OPT, canwait); 2178 if (dst->ip6po_pktinfo == NULL) 2179 goto bad; 2180 *dst->ip6po_pktinfo = *src->ip6po_pktinfo; 2181 } 2182 if (src->ip6po_nexthop) { 2183 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len, 2184 M_IP6OPT, canwait); 2185 if (dst->ip6po_nexthop == NULL) 2186 goto bad; 2187 memcpy(dst->ip6po_nexthop, src->ip6po_nexthop, 2188 src->ip6po_nexthop->sa_len); 2189 } 2190 PKTOPT_EXTHDRCPY(ip6po_hbh); 2191 PKTOPT_EXTHDRCPY(ip6po_dest1); 2192 PKTOPT_EXTHDRCPY(ip6po_dest2); 2193 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */ 2194 return (0); 2195 2196 bad: 2197 if (dst->ip6po_pktinfo) free(dst->ip6po_pktinfo, M_IP6OPT); 2198 if (dst->ip6po_nexthop) free(dst->ip6po_nexthop, M_IP6OPT); 2199 if (dst->ip6po_hbh) free(dst->ip6po_hbh, M_IP6OPT); 2200 if (dst->ip6po_dest1) free(dst->ip6po_dest1, M_IP6OPT); 2201 if (dst->ip6po_dest2) free(dst->ip6po_dest2, M_IP6OPT); 2202 if (dst->ip6po_rthdr) free(dst->ip6po_rthdr, M_IP6OPT); 2203 2204 return (ENOBUFS); 2205 } 2206 #undef PKTOPT_EXTHDRCPY 2207 2208 struct ip6_pktopts * 2209 ip6_copypktopts(struct ip6_pktopts *src, int canwait) 2210 { 2211 int error; 2212 struct ip6_pktopts *dst; 2213 2214 dst = malloc(sizeof(*dst), M_IP6OPT, canwait); 2215 if (dst == NULL) 2216 return (NULL); 2217 ip6_initpktopts(dst); 2218 2219 if ((error = copypktopts(dst, src, canwait)) != 0) { 2220 free(dst, M_IP6OPT); 2221 return (NULL); 2222 } 2223 2224 return (dst); 2225 } 2226 2227 void 2228 ip6_freepcbopts(struct ip6_pktopts *pktopt) 2229 { 2230 if (pktopt == NULL) 2231 return; 2232 2233 ip6_clearpktopts(pktopt, -1); 2234 2235 free(pktopt, M_IP6OPT); 2236 } 2237 2238 /* 2239 * Set the IP6 multicast options in response to user setsockopt(). 2240 */ 2241 static int 2242 ip6_setmoptions(const struct sockopt *sopt, struct ip6_moptions **im6op) 2243 { 2244 int error = 0; 2245 u_int loop, ifindex; 2246 struct ipv6_mreq mreq; 2247 struct ifnet *ifp; 2248 struct ip6_moptions *im6o = *im6op; 2249 struct route ro; 2250 struct in6_multi_mship *imm; 2251 struct lwp *l = curlwp; /* XXX */ 2252 2253 if (im6o == NULL) { 2254 /* 2255 * No multicast option buffer attached to the pcb; 2256 * allocate one and initialize to default values. 2257 */ 2258 im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_NOWAIT); 2259 if (im6o == NULL) 2260 return (ENOBUFS); 2261 2262 *im6op = im6o; 2263 im6o->im6o_multicast_ifp = NULL; 2264 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 2265 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP; 2266 LIST_INIT(&im6o->im6o_memberships); 2267 } 2268 2269 switch (sopt->sopt_name) { 2270 2271 case IPV6_MULTICAST_IF: 2272 /* 2273 * Select the interface for outgoing multicast packets. 2274 */ 2275 error = sockopt_get(sopt, &ifindex, sizeof(ifindex)); 2276 if (error != 0) 2277 break; 2278 2279 if (ifindex != 0) { 2280 if (if_indexlim <= ifindex || !ifindex2ifnet[ifindex]) { 2281 error = ENXIO; /* XXX EINVAL? */ 2282 break; 2283 } 2284 ifp = ifindex2ifnet[ifindex]; 2285 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 2286 error = EADDRNOTAVAIL; 2287 break; 2288 } 2289 } else 2290 ifp = NULL; 2291 im6o->im6o_multicast_ifp = ifp; 2292 break; 2293 2294 case IPV6_MULTICAST_HOPS: 2295 { 2296 /* 2297 * Set the IP6 hoplimit for outgoing multicast packets. 2298 */ 2299 int optval; 2300 2301 error = sockopt_getint(sopt, &optval); 2302 if (error != 0) 2303 break; 2304 2305 if (optval < -1 || optval >= 256) 2306 error = EINVAL; 2307 else if (optval == -1) 2308 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 2309 else 2310 im6o->im6o_multicast_hlim = optval; 2311 break; 2312 } 2313 2314 case IPV6_MULTICAST_LOOP: 2315 /* 2316 * Set the loopback flag for outgoing multicast packets. 2317 * Must be zero or one. 2318 */ 2319 error = sockopt_get(sopt, &loop, sizeof(loop)); 2320 if (error != 0) 2321 break; 2322 if (loop > 1) { 2323 error = EINVAL; 2324 break; 2325 } 2326 im6o->im6o_multicast_loop = loop; 2327 break; 2328 2329 case IPV6_JOIN_GROUP: 2330 /* 2331 * Add a multicast group membership. 2332 * Group must be a valid IP6 multicast address. 2333 */ 2334 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 2335 if (error != 0) 2336 break; 2337 2338 if (IN6_IS_ADDR_UNSPECIFIED(&mreq.ipv6mr_multiaddr)) { 2339 /* 2340 * We use the unspecified address to specify to accept 2341 * all multicast addresses. Only super user is allowed 2342 * to do this. 2343 */ 2344 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_IPV6, 2345 KAUTH_REQ_NETWORK_IPV6_JOIN_MULTICAST, NULL, NULL, NULL)) 2346 { 2347 error = EACCES; 2348 break; 2349 } 2350 } else if (!IN6_IS_ADDR_MULTICAST(&mreq.ipv6mr_multiaddr)) { 2351 error = EINVAL; 2352 break; 2353 } 2354 2355 /* 2356 * If no interface was explicitly specified, choose an 2357 * appropriate one according to the given multicast address. 2358 */ 2359 if (mreq.ipv6mr_interface == 0) { 2360 struct rtentry *rt; 2361 union { 2362 struct sockaddr dst; 2363 struct sockaddr_in6 dst6; 2364 } u; 2365 2366 /* 2367 * Look up the routing table for the 2368 * address, and choose the outgoing interface. 2369 * XXX: is it a good approach? 2370 */ 2371 memset(&ro, 0, sizeof(ro)); 2372 sockaddr_in6_init(&u.dst6, &mreq.ipv6mr_multiaddr, 0, 2373 0, 0); 2374 rtcache_setdst(&ro, &u.dst); 2375 ifp = (rt = rtcache_init(&ro)) != NULL ? rt->rt_ifp 2376 : NULL; 2377 rtcache_free(&ro); 2378 } else { 2379 /* 2380 * If the interface is specified, validate it. 2381 */ 2382 if (if_indexlim <= mreq.ipv6mr_interface || 2383 !ifindex2ifnet[mreq.ipv6mr_interface]) { 2384 error = ENXIO; /* XXX EINVAL? */ 2385 break; 2386 } 2387 ifp = ifindex2ifnet[mreq.ipv6mr_interface]; 2388 } 2389 2390 /* 2391 * See if we found an interface, and confirm that it 2392 * supports multicast 2393 */ 2394 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 2395 error = EADDRNOTAVAIL; 2396 break; 2397 } 2398 2399 if (in6_setscope(&mreq.ipv6mr_multiaddr, ifp, NULL)) { 2400 error = EADDRNOTAVAIL; /* XXX: should not happen */ 2401 break; 2402 } 2403 2404 /* 2405 * See if the membership already exists. 2406 */ 2407 for (imm = im6o->im6o_memberships.lh_first; 2408 imm != NULL; imm = imm->i6mm_chain.le_next) 2409 if (imm->i6mm_maddr->in6m_ifp == ifp && 2410 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2411 &mreq.ipv6mr_multiaddr)) 2412 break; 2413 if (imm != NULL) { 2414 error = EADDRINUSE; 2415 break; 2416 } 2417 /* 2418 * Everything looks good; add a new record to the multicast 2419 * address list for the given interface. 2420 */ 2421 imm = in6_joingroup(ifp, &mreq.ipv6mr_multiaddr, &error, 0); 2422 if (imm == NULL) 2423 break; 2424 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); 2425 break; 2426 2427 case IPV6_LEAVE_GROUP: 2428 /* 2429 * Drop a multicast group membership. 2430 * Group must be a valid IP6 multicast address. 2431 */ 2432 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 2433 if (error != 0) 2434 break; 2435 2436 /* 2437 * If an interface address was specified, get a pointer 2438 * to its ifnet structure. 2439 */ 2440 if (mreq.ipv6mr_interface != 0) { 2441 if (if_indexlim <= mreq.ipv6mr_interface || 2442 !ifindex2ifnet[mreq.ipv6mr_interface]) { 2443 error = ENXIO; /* XXX EINVAL? */ 2444 break; 2445 } 2446 ifp = ifindex2ifnet[mreq.ipv6mr_interface]; 2447 } else 2448 ifp = NULL; 2449 2450 /* Fill in the scope zone ID */ 2451 if (ifp) { 2452 if (in6_setscope(&mreq.ipv6mr_multiaddr, ifp, NULL)) { 2453 /* XXX: should not happen */ 2454 error = EADDRNOTAVAIL; 2455 break; 2456 } 2457 } else if (mreq.ipv6mr_interface != 0) { 2458 /* 2459 * XXX: This case would happens when the (positive) 2460 * index is in the valid range, but the corresponding 2461 * interface has been detached dynamically. The above 2462 * check probably avoids such case to happen here, but 2463 * we check it explicitly for safety. 2464 */ 2465 error = EADDRNOTAVAIL; 2466 break; 2467 } else { /* ipv6mr_interface == 0 */ 2468 struct sockaddr_in6 sa6_mc; 2469 2470 /* 2471 * The API spec says as follows: 2472 * If the interface index is specified as 0, the 2473 * system may choose a multicast group membership to 2474 * drop by matching the multicast address only. 2475 * On the other hand, we cannot disambiguate the scope 2476 * zone unless an interface is provided. Thus, we 2477 * check if there's ambiguity with the default scope 2478 * zone as the last resort. 2479 */ 2480 sockaddr_in6_init(&sa6_mc, &mreq.ipv6mr_multiaddr, 2481 0, 0, 0); 2482 error = sa6_embedscope(&sa6_mc, ip6_use_defzone); 2483 if (error != 0) 2484 break; 2485 mreq.ipv6mr_multiaddr = sa6_mc.sin6_addr; 2486 } 2487 2488 /* 2489 * Find the membership in the membership list. 2490 */ 2491 for (imm = im6o->im6o_memberships.lh_first; 2492 imm != NULL; imm = imm->i6mm_chain.le_next) { 2493 if ((ifp == NULL || imm->i6mm_maddr->in6m_ifp == ifp) && 2494 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2495 &mreq.ipv6mr_multiaddr)) 2496 break; 2497 } 2498 if (imm == NULL) { 2499 /* Unable to resolve interface */ 2500 error = EADDRNOTAVAIL; 2501 break; 2502 } 2503 /* 2504 * Give up the multicast address record to which the 2505 * membership points. 2506 */ 2507 LIST_REMOVE(imm, i6mm_chain); 2508 in6_leavegroup(imm); 2509 break; 2510 2511 default: 2512 error = EOPNOTSUPP; 2513 break; 2514 } 2515 2516 /* 2517 * If all options have default values, no need to keep the mbuf. 2518 */ 2519 if (im6o->im6o_multicast_ifp == NULL && 2520 im6o->im6o_multicast_hlim == ip6_defmcasthlim && 2521 im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP && 2522 im6o->im6o_memberships.lh_first == NULL) { 2523 free(*im6op, M_IPMOPTS); 2524 *im6op = NULL; 2525 } 2526 2527 return (error); 2528 } 2529 2530 /* 2531 * Return the IP6 multicast options in response to user getsockopt(). 2532 */ 2533 static int 2534 ip6_getmoptions(struct sockopt *sopt, struct ip6_moptions *im6o) 2535 { 2536 u_int optval; 2537 int error; 2538 2539 switch (sopt->sopt_name) { 2540 case IPV6_MULTICAST_IF: 2541 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL) 2542 optval = 0; 2543 else 2544 optval = im6o->im6o_multicast_ifp->if_index; 2545 2546 error = sockopt_set(sopt, &optval, sizeof(optval)); 2547 break; 2548 2549 case IPV6_MULTICAST_HOPS: 2550 if (im6o == NULL) 2551 optval = ip6_defmcasthlim; 2552 else 2553 optval = im6o->im6o_multicast_hlim; 2554 2555 error = sockopt_set(sopt, &optval, sizeof(optval)); 2556 break; 2557 2558 case IPV6_MULTICAST_LOOP: 2559 if (im6o == NULL) 2560 optval = IPV6_DEFAULT_MULTICAST_LOOP; 2561 else 2562 optval = im6o->im6o_multicast_loop; 2563 2564 error = sockopt_set(sopt, &optval, sizeof(optval)); 2565 break; 2566 2567 default: 2568 error = EOPNOTSUPP; 2569 } 2570 2571 return (error); 2572 } 2573 2574 /* 2575 * Discard the IP6 multicast options. 2576 */ 2577 void 2578 ip6_freemoptions(struct ip6_moptions *im6o) 2579 { 2580 struct in6_multi_mship *imm; 2581 2582 if (im6o == NULL) 2583 return; 2584 2585 while ((imm = im6o->im6o_memberships.lh_first) != NULL) { 2586 LIST_REMOVE(imm, i6mm_chain); 2587 in6_leavegroup(imm); 2588 } 2589 free(im6o, M_IPMOPTS); 2590 } 2591 2592 /* 2593 * Set IPv6 outgoing packet options based on advanced API. 2594 */ 2595 int 2596 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt, 2597 struct ip6_pktopts *stickyopt, kauth_cred_t cred, int uproto) 2598 { 2599 struct cmsghdr *cm = 0; 2600 2601 if (control == NULL || opt == NULL) 2602 return (EINVAL); 2603 2604 ip6_initpktopts(opt); 2605 if (stickyopt) { 2606 int error; 2607 2608 /* 2609 * If stickyopt is provided, make a local copy of the options 2610 * for this particular packet, then override them by ancillary 2611 * objects. 2612 * XXX: copypktopts() does not copy the cached route to a next 2613 * hop (if any). This is not very good in terms of efficiency, 2614 * but we can allow this since this option should be rarely 2615 * used. 2616 */ 2617 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0) 2618 return (error); 2619 } 2620 2621 /* 2622 * XXX: Currently, we assume all the optional information is stored 2623 * in a single mbuf. 2624 */ 2625 if (control->m_next) 2626 return (EINVAL); 2627 2628 /* XXX if cm->cmsg_len is not aligned, control->m_len can become <0 */ 2629 for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len), 2630 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 2631 int error; 2632 2633 if (control->m_len < CMSG_LEN(0)) 2634 return (EINVAL); 2635 2636 cm = mtod(control, struct cmsghdr *); 2637 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len) 2638 return (EINVAL); 2639 if (cm->cmsg_level != IPPROTO_IPV6) 2640 continue; 2641 2642 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm), 2643 cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto); 2644 if (error) 2645 return (error); 2646 } 2647 2648 return (0); 2649 } 2650 2651 /* 2652 * Set a particular packet option, as a sticky option or an ancillary data 2653 * item. "len" can be 0 only when it's a sticky option. 2654 * We have 4 cases of combination of "sticky" and "cmsg": 2655 * "sticky=0, cmsg=0": impossible 2656 * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data 2657 * "sticky=1, cmsg=0": RFC3542 socket option 2658 * "sticky=1, cmsg=1": RFC2292 socket option 2659 */ 2660 static int 2661 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt, 2662 kauth_cred_t cred, int sticky, int cmsg, int uproto) 2663 { 2664 int minmtupolicy; 2665 int error; 2666 2667 if (!sticky && !cmsg) { 2668 #ifdef DIAGNOSTIC 2669 printf("ip6_setpktopt: impossible case\n"); 2670 #endif 2671 return (EINVAL); 2672 } 2673 2674 /* 2675 * IPV6_2292xxx is for backward compatibility to RFC2292, and should 2676 * not be specified in the context of RFC3542. Conversely, 2677 * RFC3542 types should not be specified in the context of RFC2292. 2678 */ 2679 if (!cmsg) { 2680 switch (optname) { 2681 case IPV6_2292PKTINFO: 2682 case IPV6_2292HOPLIMIT: 2683 case IPV6_2292NEXTHOP: 2684 case IPV6_2292HOPOPTS: 2685 case IPV6_2292DSTOPTS: 2686 case IPV6_2292RTHDR: 2687 case IPV6_2292PKTOPTIONS: 2688 return (ENOPROTOOPT); 2689 } 2690 } 2691 if (sticky && cmsg) { 2692 switch (optname) { 2693 case IPV6_PKTINFO: 2694 case IPV6_HOPLIMIT: 2695 case IPV6_NEXTHOP: 2696 case IPV6_HOPOPTS: 2697 case IPV6_DSTOPTS: 2698 case IPV6_RTHDRDSTOPTS: 2699 case IPV6_RTHDR: 2700 case IPV6_USE_MIN_MTU: 2701 case IPV6_DONTFRAG: 2702 case IPV6_OTCLASS: 2703 case IPV6_TCLASS: 2704 return (ENOPROTOOPT); 2705 } 2706 } 2707 2708 switch (optname) { 2709 #ifdef RFC2292 2710 case IPV6_2292PKTINFO: 2711 #endif 2712 case IPV6_PKTINFO: 2713 { 2714 struct ifnet *ifp = NULL; 2715 struct in6_pktinfo *pktinfo; 2716 2717 if (len != sizeof(struct in6_pktinfo)) 2718 return (EINVAL); 2719 2720 pktinfo = (struct in6_pktinfo *)buf; 2721 2722 /* 2723 * An application can clear any sticky IPV6_PKTINFO option by 2724 * doing a "regular" setsockopt with ipi6_addr being 2725 * in6addr_any and ipi6_ifindex being zero. 2726 * [RFC 3542, Section 6] 2727 */ 2728 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo && 2729 pktinfo->ipi6_ifindex == 0 && 2730 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2731 ip6_clearpktopts(opt, optname); 2732 break; 2733 } 2734 2735 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO && 2736 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2737 return (EINVAL); 2738 } 2739 2740 /* validate the interface index if specified. */ 2741 if (pktinfo->ipi6_ifindex >= if_indexlim) { 2742 return (ENXIO); 2743 } 2744 if (pktinfo->ipi6_ifindex) { 2745 ifp = ifindex2ifnet[pktinfo->ipi6_ifindex]; 2746 if (ifp == NULL) 2747 return (ENXIO); 2748 } 2749 2750 /* 2751 * We store the address anyway, and let in6_selectsrc() 2752 * validate the specified address. This is because ipi6_addr 2753 * may not have enough information about its scope zone, and 2754 * we may need additional information (such as outgoing 2755 * interface or the scope zone of a destination address) to 2756 * disambiguate the scope. 2757 * XXX: the delay of the validation may confuse the 2758 * application when it is used as a sticky option. 2759 */ 2760 if (opt->ip6po_pktinfo == NULL) { 2761 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo), 2762 M_IP6OPT, M_NOWAIT); 2763 if (opt->ip6po_pktinfo == NULL) 2764 return (ENOBUFS); 2765 } 2766 memcpy(opt->ip6po_pktinfo, pktinfo, sizeof(*pktinfo)); 2767 break; 2768 } 2769 2770 #ifdef RFC2292 2771 case IPV6_2292HOPLIMIT: 2772 #endif 2773 case IPV6_HOPLIMIT: 2774 { 2775 int *hlimp; 2776 2777 /* 2778 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT 2779 * to simplify the ordering among hoplimit options. 2780 */ 2781 if (optname == IPV6_HOPLIMIT && sticky) 2782 return (ENOPROTOOPT); 2783 2784 if (len != sizeof(int)) 2785 return (EINVAL); 2786 hlimp = (int *)buf; 2787 if (*hlimp < -1 || *hlimp > 255) 2788 return (EINVAL); 2789 2790 opt->ip6po_hlim = *hlimp; 2791 break; 2792 } 2793 2794 case IPV6_OTCLASS: 2795 if (len != sizeof(u_int8_t)) 2796 return (EINVAL); 2797 2798 opt->ip6po_tclass = *(u_int8_t *)buf; 2799 break; 2800 2801 case IPV6_TCLASS: 2802 { 2803 int tclass; 2804 2805 if (len != sizeof(int)) 2806 return (EINVAL); 2807 tclass = *(int *)buf; 2808 if (tclass < -1 || tclass > 255) 2809 return (EINVAL); 2810 2811 opt->ip6po_tclass = tclass; 2812 break; 2813 } 2814 2815 #ifdef RFC2292 2816 case IPV6_2292NEXTHOP: 2817 #endif 2818 case IPV6_NEXTHOP: 2819 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2820 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2821 if (error) 2822 return (error); 2823 2824 if (len == 0) { /* just remove the option */ 2825 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2826 break; 2827 } 2828 2829 /* check if cmsg_len is large enough for sa_len */ 2830 if (len < sizeof(struct sockaddr) || len < *buf) 2831 return (EINVAL); 2832 2833 switch (((struct sockaddr *)buf)->sa_family) { 2834 case AF_INET6: 2835 { 2836 struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf; 2837 2838 if (sa6->sin6_len != sizeof(struct sockaddr_in6)) 2839 return (EINVAL); 2840 2841 if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) || 2842 IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 2843 return (EINVAL); 2844 } 2845 if ((error = sa6_embedscope(sa6, ip6_use_defzone)) 2846 != 0) { 2847 return (error); 2848 } 2849 break; 2850 } 2851 case AF_LINK: /* eventually be supported? */ 2852 default: 2853 return (EAFNOSUPPORT); 2854 } 2855 2856 /* turn off the previous option, then set the new option. */ 2857 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2858 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT); 2859 if (opt->ip6po_nexthop == NULL) 2860 return (ENOBUFS); 2861 memcpy(opt->ip6po_nexthop, buf, *buf); 2862 break; 2863 2864 #ifdef RFC2292 2865 case IPV6_2292HOPOPTS: 2866 #endif 2867 case IPV6_HOPOPTS: 2868 { 2869 struct ip6_hbh *hbh; 2870 int hbhlen; 2871 2872 /* 2873 * XXX: We don't allow a non-privileged user to set ANY HbH 2874 * options, since per-option restriction has too much 2875 * overhead. 2876 */ 2877 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2878 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2879 if (error) 2880 return (error); 2881 2882 if (len == 0) { 2883 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2884 break; /* just remove the option */ 2885 } 2886 2887 /* message length validation */ 2888 if (len < sizeof(struct ip6_hbh)) 2889 return (EINVAL); 2890 hbh = (struct ip6_hbh *)buf; 2891 hbhlen = (hbh->ip6h_len + 1) << 3; 2892 if (len != hbhlen) 2893 return (EINVAL); 2894 2895 /* turn off the previous option, then set the new option. */ 2896 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2897 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT); 2898 if (opt->ip6po_hbh == NULL) 2899 return (ENOBUFS); 2900 memcpy(opt->ip6po_hbh, hbh, hbhlen); 2901 2902 break; 2903 } 2904 2905 #ifdef RFC2292 2906 case IPV6_2292DSTOPTS: 2907 #endif 2908 case IPV6_DSTOPTS: 2909 case IPV6_RTHDRDSTOPTS: 2910 { 2911 struct ip6_dest *dest, **newdest = NULL; 2912 int destlen; 2913 2914 /* XXX: see the comment for IPV6_HOPOPTS */ 2915 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2916 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2917 if (error) 2918 return (error); 2919 2920 if (len == 0) { 2921 ip6_clearpktopts(opt, optname); 2922 break; /* just remove the option */ 2923 } 2924 2925 /* message length validation */ 2926 if (len < sizeof(struct ip6_dest)) 2927 return (EINVAL); 2928 dest = (struct ip6_dest *)buf; 2929 destlen = (dest->ip6d_len + 1) << 3; 2930 if (len != destlen) 2931 return (EINVAL); 2932 /* 2933 * Determine the position that the destination options header 2934 * should be inserted; before or after the routing header. 2935 */ 2936 switch (optname) { 2937 case IPV6_2292DSTOPTS: 2938 /* 2939 * The old advanced API is ambiguous on this point. 2940 * Our approach is to determine the position based 2941 * according to the existence of a routing header. 2942 * Note, however, that this depends on the order of the 2943 * extension headers in the ancillary data; the 1st 2944 * part of the destination options header must appear 2945 * before the routing header in the ancillary data, 2946 * too. 2947 * RFC3542 solved the ambiguity by introducing 2948 * separate ancillary data or option types. 2949 */ 2950 if (opt->ip6po_rthdr == NULL) 2951 newdest = &opt->ip6po_dest1; 2952 else 2953 newdest = &opt->ip6po_dest2; 2954 break; 2955 case IPV6_RTHDRDSTOPTS: 2956 newdest = &opt->ip6po_dest1; 2957 break; 2958 case IPV6_DSTOPTS: 2959 newdest = &opt->ip6po_dest2; 2960 break; 2961 } 2962 2963 /* turn off the previous option, then set the new option. */ 2964 ip6_clearpktopts(opt, optname); 2965 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT); 2966 if (*newdest == NULL) 2967 return (ENOBUFS); 2968 memcpy(*newdest, dest, destlen); 2969 2970 break; 2971 } 2972 2973 #ifdef RFC2292 2974 case IPV6_2292RTHDR: 2975 #endif 2976 case IPV6_RTHDR: 2977 { 2978 struct ip6_rthdr *rth; 2979 int rthlen; 2980 2981 if (len == 0) { 2982 ip6_clearpktopts(opt, IPV6_RTHDR); 2983 break; /* just remove the option */ 2984 } 2985 2986 /* message length validation */ 2987 if (len < sizeof(struct ip6_rthdr)) 2988 return (EINVAL); 2989 rth = (struct ip6_rthdr *)buf; 2990 rthlen = (rth->ip6r_len + 1) << 3; 2991 if (len != rthlen) 2992 return (EINVAL); 2993 switch (rth->ip6r_type) { 2994 case IPV6_RTHDR_TYPE_0: 2995 if (rth->ip6r_len == 0) /* must contain one addr */ 2996 return (EINVAL); 2997 if (rth->ip6r_len % 2) /* length must be even */ 2998 return (EINVAL); 2999 if (rth->ip6r_len / 2 != rth->ip6r_segleft) 3000 return (EINVAL); 3001 break; 3002 default: 3003 return (EINVAL); /* not supported */ 3004 } 3005 /* turn off the previous option */ 3006 ip6_clearpktopts(opt, IPV6_RTHDR); 3007 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT); 3008 if (opt->ip6po_rthdr == NULL) 3009 return (ENOBUFS); 3010 memcpy(opt->ip6po_rthdr, rth, rthlen); 3011 break; 3012 } 3013 3014 case IPV6_USE_MIN_MTU: 3015 if (len != sizeof(int)) 3016 return (EINVAL); 3017 minmtupolicy = *(int *)buf; 3018 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY && 3019 minmtupolicy != IP6PO_MINMTU_DISABLE && 3020 minmtupolicy != IP6PO_MINMTU_ALL) { 3021 return (EINVAL); 3022 } 3023 opt->ip6po_minmtu = minmtupolicy; 3024 break; 3025 3026 case IPV6_DONTFRAG: 3027 if (len != sizeof(int)) 3028 return (EINVAL); 3029 3030 if (uproto == IPPROTO_TCP || *(int *)buf == 0) { 3031 /* 3032 * we ignore this option for TCP sockets. 3033 * (RFC3542 leaves this case unspecified.) 3034 */ 3035 opt->ip6po_flags &= ~IP6PO_DONTFRAG; 3036 } else 3037 opt->ip6po_flags |= IP6PO_DONTFRAG; 3038 break; 3039 3040 default: 3041 return (ENOPROTOOPT); 3042 } /* end of switch */ 3043 3044 return (0); 3045 } 3046 3047 /* 3048 * Routine called from ip6_output() to loop back a copy of an IP6 multicast 3049 * packet to the input queue of a specified interface. Note that this 3050 * calls the output routine of the loopback "driver", but with an interface 3051 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 3052 */ 3053 void 3054 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, 3055 const struct sockaddr_in6 *dst) 3056 { 3057 struct mbuf *copym; 3058 struct ip6_hdr *ip6; 3059 3060 copym = m_copy(m, 0, M_COPYALL); 3061 if (copym == NULL) 3062 return; 3063 3064 /* 3065 * Make sure to deep-copy IPv6 header portion in case the data 3066 * is in an mbuf cluster, so that we can safely override the IPv6 3067 * header portion later. 3068 */ 3069 if ((copym->m_flags & M_EXT) != 0 || 3070 copym->m_len < sizeof(struct ip6_hdr)) { 3071 copym = m_pullup(copym, sizeof(struct ip6_hdr)); 3072 if (copym == NULL) 3073 return; 3074 } 3075 3076 #ifdef DIAGNOSTIC 3077 if (copym->m_len < sizeof(*ip6)) { 3078 m_freem(copym); 3079 return; 3080 } 3081 #endif 3082 3083 ip6 = mtod(copym, struct ip6_hdr *); 3084 /* 3085 * clear embedded scope identifiers if necessary. 3086 * in6_clearscope will touch the addresses only when necessary. 3087 */ 3088 in6_clearscope(&ip6->ip6_src); 3089 in6_clearscope(&ip6->ip6_dst); 3090 3091 (void)looutput(ifp, copym, (const struct sockaddr *)dst, NULL); 3092 } 3093 3094 /* 3095 * Chop IPv6 header off from the payload. 3096 */ 3097 static int 3098 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs) 3099 { 3100 struct mbuf *mh; 3101 struct ip6_hdr *ip6; 3102 3103 ip6 = mtod(m, struct ip6_hdr *); 3104 if (m->m_len > sizeof(*ip6)) { 3105 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 3106 if (mh == 0) { 3107 m_freem(m); 3108 return ENOBUFS; 3109 } 3110 M_MOVE_PKTHDR(mh, m); 3111 MH_ALIGN(mh, sizeof(*ip6)); 3112 m->m_len -= sizeof(*ip6); 3113 m->m_data += sizeof(*ip6); 3114 mh->m_next = m; 3115 m = mh; 3116 m->m_len = sizeof(*ip6); 3117 bcopy((void *)ip6, mtod(m, void *), sizeof(*ip6)); 3118 } 3119 exthdrs->ip6e_ip6 = m; 3120 return 0; 3121 } 3122 3123 /* 3124 * Compute IPv6 extension header length. 3125 */ 3126 int 3127 ip6_optlen(struct in6pcb *in6p) 3128 { 3129 int len; 3130 3131 if (!in6p->in6p_outputopts) 3132 return 0; 3133 3134 len = 0; 3135 #define elen(x) \ 3136 (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0) 3137 3138 len += elen(in6p->in6p_outputopts->ip6po_hbh); 3139 len += elen(in6p->in6p_outputopts->ip6po_dest1); 3140 len += elen(in6p->in6p_outputopts->ip6po_rthdr); 3141 len += elen(in6p->in6p_outputopts->ip6po_dest2); 3142 return len; 3143 #undef elen 3144 } 3145