1 /* $NetBSD: ip6_output.c,v 1.147 2012/03/22 20:34:41 drochner 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 1.147 2012/03/22 20:34:41 drochner Exp $"); 66 67 #include "opt_inet.h" 68 #include "opt_inet6.h" 69 #include "opt_ipsec.h" 70 #include "opt_pfil_hooks.h" 71 72 #include <sys/param.h> 73 #include <sys/malloc.h> 74 #include <sys/mbuf.h> 75 #include <sys/errno.h> 76 #include <sys/protosw.h> 77 #include <sys/socket.h> 78 #include <sys/socketvar.h> 79 #include <sys/systm.h> 80 #include <sys/proc.h> 81 #include <sys/kauth.h> 82 83 #include <net/if.h> 84 #include <net/route.h> 85 #ifdef PFIL_HOOKS 86 #include <net/pfil.h> 87 #endif 88 89 #include <netinet/in.h> 90 #include <netinet/in_var.h> 91 #include <netinet/ip6.h> 92 #include <netinet/icmp6.h> 93 #include <netinet/in_offload.h> 94 #include <netinet6/in6_offload.h> 95 #include <netinet6/ip6_var.h> 96 #include <netinet6/ip6_private.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/nd6.h> 99 #include <netinet6/ip6protosw.h> 100 #include <netinet6/scope6_var.h> 101 102 #ifdef FAST_IPSEC 103 #include <netipsec/ipsec.h> 104 #include <netipsec/ipsec6.h> 105 #include <netipsec/key.h> 106 #include <netipsec/xform.h> 107 #endif 108 109 110 #include <net/net_osdep.h> 111 112 #ifdef PFIL_HOOKS 113 extern struct pfil_head inet6_pfil_hook; /* XXX */ 114 #endif 115 116 struct ip6_exthdrs { 117 struct mbuf *ip6e_ip6; 118 struct mbuf *ip6e_hbh; 119 struct mbuf *ip6e_dest1; 120 struct mbuf *ip6e_rthdr; 121 struct mbuf *ip6e_dest2; 122 }; 123 124 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, 125 kauth_cred_t, int); 126 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *); 127 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, kauth_cred_t, 128 int, int, int); 129 static int ip6_setmoptions(const struct sockopt *, struct ip6_moptions **); 130 static int ip6_getmoptions(struct sockopt *, struct ip6_moptions *); 131 static int ip6_copyexthdr(struct mbuf **, void *, int); 132 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int, 133 struct ip6_frag **); 134 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t); 135 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *); 136 static int ip6_getpmtu(struct route *, struct route *, struct ifnet *, 137 const struct in6_addr *, u_long *, int *); 138 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int); 139 140 #ifdef RFC2292 141 static int ip6_pcbopts(struct ip6_pktopts **, struct socket *, struct sockopt *); 142 #endif 143 144 /* 145 * IP6 output. The packet in mbuf chain m contains a skeletal IP6 146 * header (with pri, len, nxt, hlim, src, dst). 147 * This function may modify ver and hlim only. 148 * The mbuf chain containing the packet will be freed. 149 * The mbuf opt, if present, will not be freed. 150 * 151 * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and 152 * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one, 153 * which is rt_rmx.rmx_mtu. 154 */ 155 int 156 ip6_output( 157 struct mbuf *m0, 158 struct ip6_pktopts *opt, 159 struct route *ro, 160 int flags, 161 struct ip6_moptions *im6o, 162 struct socket *so, 163 struct ifnet **ifpp /* XXX: just for statistics */ 164 ) 165 { 166 struct ip6_hdr *ip6, *mhip6; 167 struct ifnet *ifp, *origifp; 168 struct mbuf *m = m0; 169 int hlen, tlen, len, off; 170 bool tso; 171 struct route ip6route; 172 struct rtentry *rt = NULL; 173 const struct sockaddr_in6 *dst = NULL; 174 struct sockaddr_in6 src_sa, dst_sa; 175 int error = 0; 176 struct in6_ifaddr *ia = NULL; 177 u_long mtu; 178 int alwaysfrag, dontfrag; 179 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; 180 struct ip6_exthdrs exthdrs; 181 struct in6_addr finaldst, src0, dst0; 182 u_int32_t zone; 183 struct route *ro_pmtu = NULL; 184 int hdrsplit = 0; 185 int needipsec = 0; 186 #ifdef FAST_IPSEC 187 struct secpolicy *sp = NULL; 188 int s; 189 #endif 190 191 memset(&ip6route, 0, sizeof(ip6route)); 192 193 #ifdef DIAGNOSTIC 194 if ((m->m_flags & M_PKTHDR) == 0) 195 panic("ip6_output: no HDR"); 196 197 if ((m->m_pkthdr.csum_flags & 198 (M_CSUM_TCPv4|M_CSUM_UDPv4|M_CSUM_TSOv4)) != 0) { 199 panic("ip6_output: IPv4 checksum offload flags: %d", 200 m->m_pkthdr.csum_flags); 201 } 202 203 if ((m->m_pkthdr.csum_flags & (M_CSUM_TCPv6|M_CSUM_UDPv6)) == 204 (M_CSUM_TCPv6|M_CSUM_UDPv6)) { 205 panic("ip6_output: conflicting checksum offload flags: %d", 206 m->m_pkthdr.csum_flags); 207 } 208 #endif 209 210 M_CSUM_DATA_IPv6_HL_SET(m->m_pkthdr.csum_data, sizeof(struct ip6_hdr)); 211 212 #define MAKE_EXTHDR(hp, mp) \ 213 do { \ 214 if (hp) { \ 215 struct ip6_ext *eh = (struct ip6_ext *)(hp); \ 216 error = ip6_copyexthdr((mp), (void *)(hp), \ 217 ((eh)->ip6e_len + 1) << 3); \ 218 if (error) \ 219 goto freehdrs; \ 220 } \ 221 } while (/*CONSTCOND*/ 0) 222 223 memset(&exthdrs, 0, sizeof(exthdrs)); 224 if (opt) { 225 /* Hop-by-Hop options header */ 226 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh); 227 /* Destination options header(1st part) */ 228 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1); 229 /* Routing header */ 230 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr); 231 /* Destination options header(2nd part) */ 232 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2); 233 } 234 235 /* 236 * Calculate the total length of the extension header chain. 237 * Keep the length of the unfragmentable part for fragmentation. 238 */ 239 optlen = 0; 240 if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len; 241 if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len; 242 if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len; 243 unfragpartlen = optlen + sizeof(struct ip6_hdr); 244 /* NOTE: we don't add AH/ESP length here. do that later. */ 245 if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len; 246 247 #ifdef FAST_IPSEC 248 /* Check the security policy (SP) for the packet */ 249 250 sp = ipsec6_check_policy(m,so,flags,&needipsec,&error); 251 if (error != 0) { 252 /* 253 * Hack: -EINVAL is used to signal that a packet 254 * should be silently discarded. This is typically 255 * because we asked key management for an SA and 256 * it was delayed (e.g. kicked up to IKE). 257 */ 258 if (error == -EINVAL) 259 error = 0; 260 goto freehdrs; 261 } 262 #endif /* FAST_IPSEC */ 263 264 265 if (needipsec && 266 (m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0) { 267 in6_delayed_cksum(m); 268 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 269 } 270 271 272 /* 273 * If we need IPsec, or there is at least one extension header, 274 * separate IP6 header from the payload. 275 */ 276 if ((needipsec || optlen) && !hdrsplit) { 277 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 278 m = NULL; 279 goto freehdrs; 280 } 281 m = exthdrs.ip6e_ip6; 282 hdrsplit++; 283 } 284 285 /* adjust pointer */ 286 ip6 = mtod(m, struct ip6_hdr *); 287 288 /* adjust mbuf packet header length */ 289 m->m_pkthdr.len += optlen; 290 plen = m->m_pkthdr.len - sizeof(*ip6); 291 292 /* If this is a jumbo payload, insert a jumbo payload option. */ 293 if (plen > IPV6_MAXPACKET) { 294 if (!hdrsplit) { 295 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 296 m = NULL; 297 goto freehdrs; 298 } 299 m = exthdrs.ip6e_ip6; 300 hdrsplit++; 301 } 302 /* adjust pointer */ 303 ip6 = mtod(m, struct ip6_hdr *); 304 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) 305 goto freehdrs; 306 optlen += 8; /* XXX JUMBOOPTLEN */ 307 ip6->ip6_plen = 0; 308 } else 309 ip6->ip6_plen = htons(plen); 310 311 /* 312 * Concatenate headers and fill in next header fields. 313 * Here we have, on "m" 314 * IPv6 payload 315 * and we insert headers accordingly. Finally, we should be getting: 316 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 317 * 318 * during the header composing process, "m" points to IPv6 header. 319 * "mprev" points to an extension header prior to esp. 320 */ 321 { 322 u_char *nexthdrp = &ip6->ip6_nxt; 323 struct mbuf *mprev = m; 324 325 /* 326 * we treat dest2 specially. this makes IPsec processing 327 * much easier. the goal here is to make mprev point the 328 * mbuf prior to dest2. 329 * 330 * result: IPv6 dest2 payload 331 * m and mprev will point to IPv6 header. 332 */ 333 if (exthdrs.ip6e_dest2) { 334 if (!hdrsplit) 335 panic("assumption failed: hdr not split"); 336 exthdrs.ip6e_dest2->m_next = m->m_next; 337 m->m_next = exthdrs.ip6e_dest2; 338 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; 339 ip6->ip6_nxt = IPPROTO_DSTOPTS; 340 } 341 342 #define MAKE_CHAIN(m, mp, p, i)\ 343 do {\ 344 if (m) {\ 345 if (!hdrsplit) \ 346 panic("assumption failed: hdr not split"); \ 347 *mtod((m), u_char *) = *(p);\ 348 *(p) = (i);\ 349 p = mtod((m), u_char *);\ 350 (m)->m_next = (mp)->m_next;\ 351 (mp)->m_next = (m);\ 352 (mp) = (m);\ 353 }\ 354 } while (/*CONSTCOND*/ 0) 355 /* 356 * result: IPv6 hbh dest1 rthdr dest2 payload 357 * m will point to IPv6 header. mprev will point to the 358 * extension header prior to dest2 (rthdr in the above case). 359 */ 360 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); 361 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, 362 IPPROTO_DSTOPTS); 363 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, 364 IPPROTO_ROUTING); 365 366 M_CSUM_DATA_IPv6_HL_SET(m->m_pkthdr.csum_data, 367 sizeof(struct ip6_hdr) + optlen); 368 } 369 370 /* 371 * If there is a routing header, replace destination address field 372 * with the first hop of the routing header. 373 */ 374 if (exthdrs.ip6e_rthdr) { 375 struct ip6_rthdr *rh; 376 struct ip6_rthdr0 *rh0; 377 struct in6_addr *addr; 378 struct sockaddr_in6 sa; 379 380 rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr, 381 struct ip6_rthdr *)); 382 finaldst = ip6->ip6_dst; 383 switch (rh->ip6r_type) { 384 case IPV6_RTHDR_TYPE_0: 385 rh0 = (struct ip6_rthdr0 *)rh; 386 addr = (struct in6_addr *)(rh0 + 1); 387 388 /* 389 * construct a sockaddr_in6 form of 390 * the first hop. 391 * 392 * XXX: we may not have enough 393 * information about its scope zone; 394 * there is no standard API to pass 395 * the information from the 396 * application. 397 */ 398 sockaddr_in6_init(&sa, addr, 0, 0, 0); 399 if ((error = sa6_embedscope(&sa, 400 ip6_use_defzone)) != 0) { 401 goto bad; 402 } 403 ip6->ip6_dst = sa.sin6_addr; 404 (void)memmove(&addr[0], &addr[1], 405 sizeof(struct in6_addr) * 406 (rh0->ip6r0_segleft - 1)); 407 addr[rh0->ip6r0_segleft - 1] = finaldst; 408 /* XXX */ 409 in6_clearscope(addr + rh0->ip6r0_segleft - 1); 410 break; 411 default: /* is it possible? */ 412 error = EINVAL; 413 goto bad; 414 } 415 } 416 417 /* Source address validation */ 418 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && 419 (flags & IPV6_UNSPECSRC) == 0) { 420 error = EOPNOTSUPP; 421 IP6_STATINC(IP6_STAT_BADSCOPE); 422 goto bad; 423 } 424 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { 425 error = EOPNOTSUPP; 426 IP6_STATINC(IP6_STAT_BADSCOPE); 427 goto bad; 428 } 429 430 IP6_STATINC(IP6_STAT_LOCALOUT); 431 432 /* 433 * Route packet. 434 */ 435 /* initialize cached route */ 436 if (ro == NULL) { 437 ro = &ip6route; 438 } 439 ro_pmtu = ro; 440 if (opt && opt->ip6po_rthdr) 441 ro = &opt->ip6po_route; 442 443 /* 444 * if specified, try to fill in the traffic class field. 445 * do not override if a non-zero value is already set. 446 * we check the diffserv field and the ecn field separately. 447 */ 448 if (opt && opt->ip6po_tclass >= 0) { 449 int mask = 0; 450 451 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0) 452 mask |= 0xfc; 453 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0) 454 mask |= 0x03; 455 if (mask != 0) 456 ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20); 457 } 458 459 /* fill in or override the hop limit field, if necessary. */ 460 if (opt && opt->ip6po_hlim != -1) 461 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 462 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 463 if (im6o != NULL) 464 ip6->ip6_hlim = im6o->im6o_multicast_hlim; 465 else 466 ip6->ip6_hlim = ip6_defmcasthlim; 467 } 468 469 #ifdef FAST_IPSEC 470 if (needipsec) { 471 s = splsoftnet(); 472 error = ipsec6_process_packet(m,sp->req); 473 474 /* 475 * Preserve KAME behaviour: ENOENT can be returned 476 * when an SA acquire is in progress. Don't propagate 477 * this to user-level; it confuses applications. 478 * XXX this will go away when the SADB is redone. 479 */ 480 if (error == ENOENT) 481 error = 0; 482 splx(s); 483 goto done; 484 } 485 #endif /* FAST_IPSEC */ 486 487 488 489 /* adjust pointer */ 490 ip6 = mtod(m, struct ip6_hdr *); 491 492 sockaddr_in6_init(&dst_sa, &ip6->ip6_dst, 0, 0, 0); 493 if ((error = in6_selectroute(&dst_sa, opt, im6o, ro, 494 &ifp, &rt, 0)) != 0) { 495 if (ifp != NULL) 496 in6_ifstat_inc(ifp, ifs6_out_discard); 497 goto bad; 498 } 499 if (rt == NULL) { 500 /* 501 * If in6_selectroute() does not return a route entry, 502 * dst may not have been updated. 503 */ 504 error = rtcache_setdst(ro, sin6tosa(&dst_sa)); 505 if (error) { 506 goto bad; 507 } 508 } 509 510 /* 511 * then rt (for unicast) and ifp must be non-NULL valid values. 512 */ 513 if ((flags & IPV6_FORWARDING) == 0) { 514 /* XXX: the FORWARDING flag can be set for mrouting. */ 515 in6_ifstat_inc(ifp, ifs6_out_request); 516 } 517 if (rt != NULL) { 518 ia = (struct in6_ifaddr *)(rt->rt_ifa); 519 rt->rt_use++; 520 } 521 522 /* 523 * The outgoing interface must be in the zone of source and 524 * destination addresses. We should use ia_ifp to support the 525 * case of sending packets to an address of our own. 526 */ 527 if (ia != NULL && ia->ia_ifp) 528 origifp = ia->ia_ifp; 529 else 530 origifp = ifp; 531 532 src0 = ip6->ip6_src; 533 if (in6_setscope(&src0, origifp, &zone)) 534 goto badscope; 535 sockaddr_in6_init(&src_sa, &ip6->ip6_src, 0, 0, 0); 536 if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id) 537 goto badscope; 538 539 dst0 = ip6->ip6_dst; 540 if (in6_setscope(&dst0, origifp, &zone)) 541 goto badscope; 542 /* re-initialize to be sure */ 543 sockaddr_in6_init(&dst_sa, &ip6->ip6_dst, 0, 0, 0); 544 if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) 545 goto badscope; 546 547 /* scope check is done. */ 548 549 if (rt == NULL || IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 550 if (dst == NULL) 551 dst = satocsin6(rtcache_getdst(ro)); 552 KASSERT(dst != NULL); 553 } else if (opt && rtcache_validate(&opt->ip6po_nextroute) != NULL) { 554 /* 555 * The nexthop is explicitly specified by the 556 * application. We assume the next hop is an IPv6 557 * address. 558 */ 559 dst = (struct sockaddr_in6 *)opt->ip6po_nexthop; 560 } else if ((rt->rt_flags & RTF_GATEWAY)) 561 dst = (struct sockaddr_in6 *)rt->rt_gateway; 562 else if (dst == NULL) 563 dst = satocsin6(rtcache_getdst(ro)); 564 565 /* 566 * XXXXXX: original code follows: 567 */ 568 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 569 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ 570 else { 571 struct in6_multi *in6m; 572 573 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; 574 575 in6_ifstat_inc(ifp, ifs6_out_mcast); 576 577 /* 578 * Confirm that the outgoing interface supports multicast. 579 */ 580 if (!(ifp->if_flags & IFF_MULTICAST)) { 581 IP6_STATINC(IP6_STAT_NOROUTE); 582 in6_ifstat_inc(ifp, ifs6_out_discard); 583 error = ENETUNREACH; 584 goto bad; 585 } 586 587 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m); 588 if (in6m != NULL && 589 (im6o == NULL || im6o->im6o_multicast_loop)) { 590 /* 591 * If we belong to the destination multicast group 592 * on the outgoing interface, and the caller did not 593 * forbid loopback, loop back a copy. 594 */ 595 KASSERT(dst != NULL); 596 ip6_mloopback(ifp, m, dst); 597 } else { 598 /* 599 * If we are acting as a multicast router, perform 600 * multicast forwarding as if the packet had just 601 * arrived on the interface to which we are about 602 * to send. The multicast forwarding function 603 * recursively calls this function, using the 604 * IPV6_FORWARDING flag to prevent infinite recursion. 605 * 606 * Multicasts that are looped back by ip6_mloopback(), 607 * above, will be forwarded by the ip6_input() routine, 608 * if necessary. 609 */ 610 if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) { 611 if (ip6_mforward(ip6, ifp, m) != 0) { 612 m_freem(m); 613 goto done; 614 } 615 } 616 } 617 /* 618 * Multicasts with a hoplimit of zero may be looped back, 619 * above, but must not be transmitted on a network. 620 * Also, multicasts addressed to the loopback interface 621 * are not sent -- the above call to ip6_mloopback() will 622 * loop back a copy if this host actually belongs to the 623 * destination group on the loopback interface. 624 */ 625 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) || 626 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) { 627 m_freem(m); 628 goto done; 629 } 630 } 631 632 /* 633 * Fill the outgoing inteface to tell the upper layer 634 * to increment per-interface statistics. 635 */ 636 if (ifpp) 637 *ifpp = ifp; 638 639 /* Determine path MTU. */ 640 if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu, 641 &alwaysfrag)) != 0) 642 goto bad; 643 644 /* 645 * The caller of this function may specify to use the minimum MTU 646 * in some cases. 647 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU 648 * setting. The logic is a bit complicated; by default, unicast 649 * packets will follow path MTU while multicast packets will be sent at 650 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets 651 * including unicast ones will be sent at the minimum MTU. Multicast 652 * packets will always be sent at the minimum MTU unless 653 * IP6PO_MINMTU_DISABLE is explicitly specified. 654 * See RFC 3542 for more details. 655 */ 656 if (mtu > IPV6_MMTU) { 657 if ((flags & IPV6_MINMTU)) 658 mtu = IPV6_MMTU; 659 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL) 660 mtu = IPV6_MMTU; 661 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 662 (opt == NULL || 663 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) { 664 mtu = IPV6_MMTU; 665 } 666 } 667 668 /* 669 * clear embedded scope identifiers if necessary. 670 * in6_clearscope will touch the addresses only when necessary. 671 */ 672 in6_clearscope(&ip6->ip6_src); 673 in6_clearscope(&ip6->ip6_dst); 674 675 /* 676 * If the outgoing packet contains a hop-by-hop options header, 677 * it must be examined and processed even by the source node. 678 * (RFC 2460, section 4.) 679 */ 680 if (ip6->ip6_nxt == IPV6_HOPOPTS) { 681 u_int32_t dummy1; /* XXX unused */ 682 u_int32_t dummy2; /* XXX unused */ 683 int hoff = sizeof(struct ip6_hdr); 684 685 if (ip6_hopopts_input(&dummy1, &dummy2, &m, &hoff)) { 686 /* m was already freed at this point */ 687 error = EINVAL;/* better error? */ 688 goto done; 689 } 690 691 ip6 = mtod(m, struct ip6_hdr *); 692 } 693 694 #ifdef PFIL_HOOKS 695 /* 696 * Run through list of hooks for output packets. 697 */ 698 if ((error = pfil_run_hooks(&inet6_pfil_hook, &m, ifp, PFIL_OUT)) != 0) 699 goto done; 700 if (m == NULL) 701 goto done; 702 ip6 = mtod(m, struct ip6_hdr *); 703 #endif /* PFIL_HOOKS */ 704 /* 705 * Send the packet to the outgoing interface. 706 * If necessary, do IPv6 fragmentation before sending. 707 * 708 * the logic here is rather complex: 709 * 1: normal case (dontfrag == 0, alwaysfrag == 0) 710 * 1-a: send as is if tlen <= path mtu 711 * 1-b: fragment if tlen > path mtu 712 * 713 * 2: if user asks us not to fragment (dontfrag == 1) 714 * 2-a: send as is if tlen <= interface mtu 715 * 2-b: error if tlen > interface mtu 716 * 717 * 3: if we always need to attach fragment header (alwaysfrag == 1) 718 * always fragment 719 * 720 * 4: if dontfrag == 1 && alwaysfrag == 1 721 * error, as we cannot handle this conflicting request 722 */ 723 tlen = m->m_pkthdr.len; 724 tso = (m->m_pkthdr.csum_flags & M_CSUM_TSOv6) != 0; 725 if (opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) 726 dontfrag = 1; 727 else 728 dontfrag = 0; 729 730 if (dontfrag && alwaysfrag) { /* case 4 */ 731 /* conflicting request - can't transmit */ 732 error = EMSGSIZE; 733 goto bad; 734 } 735 if (dontfrag && (!tso && tlen > IN6_LINKMTU(ifp))) { /* case 2-b */ 736 /* 737 * Even if the DONTFRAG option is specified, we cannot send the 738 * packet when the data length is larger than the MTU of the 739 * outgoing interface. 740 * Notify the error by sending IPV6_PATHMTU ancillary data as 741 * well as returning an error code (the latter is not described 742 * in the API spec.) 743 */ 744 u_int32_t mtu32; 745 struct ip6ctlparam ip6cp; 746 747 mtu32 = (u_int32_t)mtu; 748 memset(&ip6cp, 0, sizeof(ip6cp)); 749 ip6cp.ip6c_cmdarg = (void *)&mtu32; 750 pfctlinput2(PRC_MSGSIZE, 751 rtcache_getdst(ro_pmtu), &ip6cp); 752 753 error = EMSGSIZE; 754 goto bad; 755 } 756 757 /* 758 * transmit packet without fragmentation 759 */ 760 if (dontfrag || (!alwaysfrag && (tlen <= mtu || tso))) { 761 /* case 1-a and 2-a */ 762 struct in6_ifaddr *ia6; 763 int sw_csum; 764 765 ip6 = mtod(m, struct ip6_hdr *); 766 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 767 if (ia6) { 768 /* Record statistics for this interface address. */ 769 ia6->ia_ifa.ifa_data.ifad_outbytes += m->m_pkthdr.len; 770 } 771 772 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 773 if ((sw_csum & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0) { 774 if (IN6_NEED_CHECKSUM(ifp, 775 sw_csum & (M_CSUM_UDPv6|M_CSUM_TCPv6))) { 776 in6_delayed_cksum(m); 777 } 778 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 779 } 780 781 KASSERT(dst != NULL); 782 if (__predict_true(!tso || 783 (ifp->if_capenable & IFCAP_TSOv6) != 0)) { 784 error = nd6_output(ifp, origifp, m, dst, rt); 785 } else { 786 error = ip6_tso_output(ifp, origifp, m, dst, rt); 787 } 788 goto done; 789 } 790 791 if (tso) { 792 error = EINVAL; /* XXX */ 793 goto bad; 794 } 795 796 /* 797 * try to fragment the packet. case 1-b and 3 798 */ 799 if (mtu < IPV6_MMTU) { 800 /* path MTU cannot be less than IPV6_MMTU */ 801 error = EMSGSIZE; 802 in6_ifstat_inc(ifp, ifs6_out_fragfail); 803 goto bad; 804 } else if (ip6->ip6_plen == 0) { 805 /* jumbo payload cannot be fragmented */ 806 error = EMSGSIZE; 807 in6_ifstat_inc(ifp, ifs6_out_fragfail); 808 goto bad; 809 } else { 810 struct mbuf **mnext, *m_frgpart; 811 struct ip6_frag *ip6f; 812 u_int32_t id = htonl(ip6_randomid()); 813 u_char nextproto; 814 #if 0 /* see below */ 815 struct ip6ctlparam ip6cp; 816 u_int32_t mtu32; 817 #endif 818 819 /* 820 * Too large for the destination or interface; 821 * fragment if possible. 822 * Must be able to put at least 8 bytes per fragment. 823 */ 824 hlen = unfragpartlen; 825 if (mtu > IPV6_MAXPACKET) 826 mtu = IPV6_MAXPACKET; 827 828 #if 0 829 /* 830 * It is believed this code is a leftover from the 831 * development of the IPV6_RECVPATHMTU sockopt and 832 * associated work to implement RFC3542. 833 * It's not entirely clear what the intent of the API 834 * is at this point, so disable this code for now. 835 * The IPV6_RECVPATHMTU sockopt and/or IPV6_DONTFRAG 836 * will send notifications if the application requests. 837 */ 838 839 /* Notify a proper path MTU to applications. */ 840 mtu32 = (u_int32_t)mtu; 841 memset(&ip6cp, 0, sizeof(ip6cp)); 842 ip6cp.ip6c_cmdarg = (void *)&mtu32; 843 pfctlinput2(PRC_MSGSIZE, 844 rtcache_getdst(ro_pmtu), &ip6cp); 845 #endif 846 847 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; 848 if (len < 8) { 849 error = EMSGSIZE; 850 in6_ifstat_inc(ifp, ifs6_out_fragfail); 851 goto bad; 852 } 853 854 mnext = &m->m_nextpkt; 855 856 /* 857 * Change the next header field of the last header in the 858 * unfragmentable part. 859 */ 860 if (exthdrs.ip6e_rthdr) { 861 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); 862 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; 863 } else if (exthdrs.ip6e_dest1) { 864 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); 865 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; 866 } else if (exthdrs.ip6e_hbh) { 867 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); 868 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; 869 } else { 870 nextproto = ip6->ip6_nxt; 871 ip6->ip6_nxt = IPPROTO_FRAGMENT; 872 } 873 874 if ((m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) 875 != 0) { 876 if (IN6_NEED_CHECKSUM(ifp, 877 m->m_pkthdr.csum_flags & 878 (M_CSUM_UDPv6|M_CSUM_TCPv6))) { 879 in6_delayed_cksum(m); 880 } 881 m->m_pkthdr.csum_flags &= ~(M_CSUM_UDPv6|M_CSUM_TCPv6); 882 } 883 884 /* 885 * Loop through length of segment after first fragment, 886 * make new header and copy data of each part and link onto 887 * chain. 888 */ 889 m0 = m; 890 for (off = hlen; off < tlen; off += len) { 891 struct mbuf *mlast; 892 893 MGETHDR(m, M_DONTWAIT, MT_HEADER); 894 if (!m) { 895 error = ENOBUFS; 896 IP6_STATINC(IP6_STAT_ODROPPED); 897 goto sendorfree; 898 } 899 m->m_pkthdr.rcvif = NULL; 900 m->m_flags = m0->m_flags & M_COPYFLAGS; 901 *mnext = m; 902 mnext = &m->m_nextpkt; 903 m->m_data += max_linkhdr; 904 mhip6 = mtod(m, struct ip6_hdr *); 905 *mhip6 = *ip6; 906 m->m_len = sizeof(*mhip6); 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 FAST_IPSEC 974 if (sp != NULL) 975 KEY_FREESP(&sp); 976 #endif /* FAST_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 static int 1151 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen, 1152 struct ip6_frag **frghdrp) 1153 { 1154 struct mbuf *n, *mlast; 1155 1156 if (hlen > sizeof(struct ip6_hdr)) { 1157 n = m_copym(m0, sizeof(struct ip6_hdr), 1158 hlen - sizeof(struct ip6_hdr), M_DONTWAIT); 1159 if (n == 0) 1160 return (ENOBUFS); 1161 m->m_next = n; 1162 } else 1163 n = m; 1164 1165 /* Search for the last mbuf of unfragmentable part. */ 1166 for (mlast = n; mlast->m_next; mlast = mlast->m_next) 1167 ; 1168 1169 if ((mlast->m_flags & M_EXT) == 0 && 1170 M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) { 1171 /* use the trailing space of the last mbuf for the fragment hdr */ 1172 *frghdrp = (struct ip6_frag *)(mtod(mlast, char *) + 1173 mlast->m_len); 1174 mlast->m_len += sizeof(struct ip6_frag); 1175 m->m_pkthdr.len += sizeof(struct ip6_frag); 1176 } else { 1177 /* allocate a new mbuf for the fragment header */ 1178 struct mbuf *mfrg; 1179 1180 MGET(mfrg, M_DONTWAIT, MT_DATA); 1181 if (mfrg == 0) 1182 return (ENOBUFS); 1183 mfrg->m_len = sizeof(struct ip6_frag); 1184 *frghdrp = mtod(mfrg, struct ip6_frag *); 1185 mlast->m_next = mfrg; 1186 } 1187 1188 return (0); 1189 } 1190 1191 static int 1192 ip6_getpmtu(struct route *ro_pmtu, struct route *ro, struct ifnet *ifp, 1193 const struct in6_addr *dst, u_long *mtup, int *alwaysfragp) 1194 { 1195 struct rtentry *rt; 1196 u_int32_t mtu = 0; 1197 int alwaysfrag = 0; 1198 int error = 0; 1199 1200 if (ro_pmtu != ro) { 1201 union { 1202 struct sockaddr dst; 1203 struct sockaddr_in6 dst6; 1204 } u; 1205 1206 /* The first hop and the final destination may differ. */ 1207 sockaddr_in6_init(&u.dst6, dst, 0, 0, 0); 1208 rt = rtcache_lookup(ro_pmtu, &u.dst); 1209 } else 1210 rt = rtcache_validate(ro_pmtu); 1211 if (rt != NULL) { 1212 u_int32_t ifmtu; 1213 1214 if (ifp == NULL) 1215 ifp = rt->rt_ifp; 1216 ifmtu = IN6_LINKMTU(ifp); 1217 mtu = rt->rt_rmx.rmx_mtu; 1218 if (mtu == 0) 1219 mtu = ifmtu; 1220 else if (mtu < IPV6_MMTU) { 1221 /* 1222 * RFC2460 section 5, last paragraph: 1223 * if we record ICMPv6 too big message with 1224 * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU 1225 * or smaller, with fragment header attached. 1226 * (fragment header is needed regardless from the 1227 * packet size, for translators to identify packets) 1228 */ 1229 alwaysfrag = 1; 1230 mtu = IPV6_MMTU; 1231 } else if (mtu > ifmtu) { 1232 /* 1233 * The MTU on the route is larger than the MTU on 1234 * the interface! This shouldn't happen, unless the 1235 * MTU of the interface has been changed after the 1236 * interface was brought up. Change the MTU in the 1237 * route to match the interface MTU (as long as the 1238 * field isn't locked). 1239 */ 1240 mtu = ifmtu; 1241 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 1242 rt->rt_rmx.rmx_mtu = mtu; 1243 } 1244 } else if (ifp) { 1245 mtu = IN6_LINKMTU(ifp); 1246 } else 1247 error = EHOSTUNREACH; /* XXX */ 1248 1249 *mtup = mtu; 1250 if (alwaysfragp) 1251 *alwaysfragp = alwaysfrag; 1252 return (error); 1253 } 1254 1255 /* 1256 * IP6 socket option processing. 1257 */ 1258 int 1259 ip6_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1260 { 1261 int optdatalen, uproto; 1262 void *optdata; 1263 struct in6pcb *in6p = sotoin6pcb(so); 1264 int error, optval; 1265 int level, optname; 1266 1267 KASSERT(sopt != NULL); 1268 1269 level = sopt->sopt_level; 1270 optname = sopt->sopt_name; 1271 1272 error = optval = 0; 1273 uproto = (int)so->so_proto->pr_protocol; 1274 1275 if (level != IPPROTO_IPV6) { 1276 return ENOPROTOOPT; 1277 } 1278 switch (op) { 1279 case PRCO_SETOPT: 1280 switch (optname) { 1281 #ifdef RFC2292 1282 case IPV6_2292PKTOPTIONS: 1283 error = ip6_pcbopts(&in6p->in6p_outputopts, so, sopt); 1284 break; 1285 #endif 1286 1287 /* 1288 * Use of some Hop-by-Hop options or some 1289 * Destination options, might require special 1290 * privilege. That is, normal applications 1291 * (without special privilege) might be forbidden 1292 * from setting certain options in outgoing packets, 1293 * and might never see certain options in received 1294 * packets. [RFC 2292 Section 6] 1295 * KAME specific note: 1296 * KAME prevents non-privileged users from sending or 1297 * receiving ANY hbh/dst options in order to avoid 1298 * overhead of parsing options in the kernel. 1299 */ 1300 case IPV6_RECVHOPOPTS: 1301 case IPV6_RECVDSTOPTS: 1302 case IPV6_RECVRTHDRDSTOPTS: 1303 error = kauth_authorize_network(kauth_cred_get(), 1304 KAUTH_NETWORK_IPV6, KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, 1305 NULL, NULL, NULL); 1306 if (error) 1307 break; 1308 /* FALLTHROUGH */ 1309 case IPV6_UNICAST_HOPS: 1310 case IPV6_HOPLIMIT: 1311 case IPV6_FAITH: 1312 1313 case IPV6_RECVPKTINFO: 1314 case IPV6_RECVHOPLIMIT: 1315 case IPV6_RECVRTHDR: 1316 case IPV6_RECVPATHMTU: 1317 case IPV6_RECVTCLASS: 1318 case IPV6_V6ONLY: 1319 error = sockopt_getint(sopt, &optval); 1320 if (error) 1321 break; 1322 switch (optname) { 1323 case IPV6_UNICAST_HOPS: 1324 if (optval < -1 || optval >= 256) 1325 error = EINVAL; 1326 else { 1327 /* -1 = kernel default */ 1328 in6p->in6p_hops = optval; 1329 } 1330 break; 1331 #define OPTSET(bit) \ 1332 do { \ 1333 if (optval) \ 1334 in6p->in6p_flags |= (bit); \ 1335 else \ 1336 in6p->in6p_flags &= ~(bit); \ 1337 } while (/*CONSTCOND*/ 0) 1338 1339 #ifdef RFC2292 1340 #define OPTSET2292(bit) \ 1341 do { \ 1342 in6p->in6p_flags |= IN6P_RFC2292; \ 1343 if (optval) \ 1344 in6p->in6p_flags |= (bit); \ 1345 else \ 1346 in6p->in6p_flags &= ~(bit); \ 1347 } while (/*CONSTCOND*/ 0) 1348 #endif 1349 1350 #define OPTBIT(bit) (in6p->in6p_flags & (bit) ? 1 : 0) 1351 1352 case IPV6_RECVPKTINFO: 1353 #ifdef RFC2292 1354 /* cannot mix with RFC2292 */ 1355 if (OPTBIT(IN6P_RFC2292)) { 1356 error = EINVAL; 1357 break; 1358 } 1359 #endif 1360 OPTSET(IN6P_PKTINFO); 1361 break; 1362 1363 case IPV6_HOPLIMIT: 1364 { 1365 struct ip6_pktopts **optp; 1366 1367 #ifdef RFC2292 1368 /* cannot mix with RFC2292 */ 1369 if (OPTBIT(IN6P_RFC2292)) { 1370 error = EINVAL; 1371 break; 1372 } 1373 #endif 1374 optp = &in6p->in6p_outputopts; 1375 error = ip6_pcbopt(IPV6_HOPLIMIT, 1376 (u_char *)&optval, 1377 sizeof(optval), 1378 optp, 1379 kauth_cred_get(), uproto); 1380 break; 1381 } 1382 1383 case IPV6_RECVHOPLIMIT: 1384 #ifdef RFC2292 1385 /* cannot mix with RFC2292 */ 1386 if (OPTBIT(IN6P_RFC2292)) { 1387 error = EINVAL; 1388 break; 1389 } 1390 #endif 1391 OPTSET(IN6P_HOPLIMIT); 1392 break; 1393 1394 case IPV6_RECVHOPOPTS: 1395 #ifdef RFC2292 1396 /* cannot mix with RFC2292 */ 1397 if (OPTBIT(IN6P_RFC2292)) { 1398 error = EINVAL; 1399 break; 1400 } 1401 #endif 1402 OPTSET(IN6P_HOPOPTS); 1403 break; 1404 1405 case IPV6_RECVDSTOPTS: 1406 #ifdef RFC2292 1407 /* cannot mix with RFC2292 */ 1408 if (OPTBIT(IN6P_RFC2292)) { 1409 error = EINVAL; 1410 break; 1411 } 1412 #endif 1413 OPTSET(IN6P_DSTOPTS); 1414 break; 1415 1416 case IPV6_RECVRTHDRDSTOPTS: 1417 #ifdef RFC2292 1418 /* cannot mix with RFC2292 */ 1419 if (OPTBIT(IN6P_RFC2292)) { 1420 error = EINVAL; 1421 break; 1422 } 1423 #endif 1424 OPTSET(IN6P_RTHDRDSTOPTS); 1425 break; 1426 1427 case IPV6_RECVRTHDR: 1428 #ifdef RFC2292 1429 /* cannot mix with RFC2292 */ 1430 if (OPTBIT(IN6P_RFC2292)) { 1431 error = EINVAL; 1432 break; 1433 } 1434 #endif 1435 OPTSET(IN6P_RTHDR); 1436 break; 1437 1438 case IPV6_FAITH: 1439 OPTSET(IN6P_FAITH); 1440 break; 1441 1442 case IPV6_RECVPATHMTU: 1443 /* 1444 * We ignore this option for TCP 1445 * sockets. 1446 * (RFC3542 leaves this case 1447 * unspecified.) 1448 */ 1449 if (uproto != IPPROTO_TCP) 1450 OPTSET(IN6P_MTU); 1451 break; 1452 1453 case IPV6_V6ONLY: 1454 /* 1455 * make setsockopt(IPV6_V6ONLY) 1456 * available only prior to bind(2). 1457 * see ipng mailing list, Jun 22 2001. 1458 */ 1459 if (in6p->in6p_lport || 1460 !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) { 1461 error = EINVAL; 1462 break; 1463 } 1464 #ifdef INET6_BINDV6ONLY 1465 if (!optval) 1466 error = EINVAL; 1467 #else 1468 OPTSET(IN6P_IPV6_V6ONLY); 1469 #endif 1470 break; 1471 case IPV6_RECVTCLASS: 1472 #ifdef RFC2292 1473 /* cannot mix with RFC2292 XXX */ 1474 if (OPTBIT(IN6P_RFC2292)) { 1475 error = EINVAL; 1476 break; 1477 } 1478 #endif 1479 OPTSET(IN6P_TCLASS); 1480 break; 1481 1482 } 1483 break; 1484 1485 case IPV6_OTCLASS: 1486 { 1487 struct ip6_pktopts **optp; 1488 u_int8_t tclass; 1489 1490 error = sockopt_get(sopt, &tclass, sizeof(tclass)); 1491 if (error) 1492 break; 1493 optp = &in6p->in6p_outputopts; 1494 error = ip6_pcbopt(optname, 1495 (u_char *)&tclass, 1496 sizeof(tclass), 1497 optp, 1498 kauth_cred_get(), uproto); 1499 break; 1500 } 1501 1502 case IPV6_TCLASS: 1503 case IPV6_DONTFRAG: 1504 case IPV6_USE_MIN_MTU: 1505 error = sockopt_getint(sopt, &optval); 1506 if (error) 1507 break; 1508 { 1509 struct ip6_pktopts **optp; 1510 optp = &in6p->in6p_outputopts; 1511 error = ip6_pcbopt(optname, 1512 (u_char *)&optval, 1513 sizeof(optval), 1514 optp, 1515 kauth_cred_get(), uproto); 1516 break; 1517 } 1518 1519 #ifdef RFC2292 1520 case IPV6_2292PKTINFO: 1521 case IPV6_2292HOPLIMIT: 1522 case IPV6_2292HOPOPTS: 1523 case IPV6_2292DSTOPTS: 1524 case IPV6_2292RTHDR: 1525 /* RFC 2292 */ 1526 error = sockopt_getint(sopt, &optval); 1527 if (error) 1528 break; 1529 1530 switch (optname) { 1531 case IPV6_2292PKTINFO: 1532 OPTSET2292(IN6P_PKTINFO); 1533 break; 1534 case IPV6_2292HOPLIMIT: 1535 OPTSET2292(IN6P_HOPLIMIT); 1536 break; 1537 case IPV6_2292HOPOPTS: 1538 /* 1539 * Check super-user privilege. 1540 * See comments for IPV6_RECVHOPOPTS. 1541 */ 1542 error = 1543 kauth_authorize_network(kauth_cred_get(), 1544 KAUTH_NETWORK_IPV6, 1545 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, 1546 NULL, NULL); 1547 if (error) 1548 return (error); 1549 OPTSET2292(IN6P_HOPOPTS); 1550 break; 1551 case IPV6_2292DSTOPTS: 1552 error = 1553 kauth_authorize_network(kauth_cred_get(), 1554 KAUTH_NETWORK_IPV6, 1555 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, 1556 NULL, NULL); 1557 if (error) 1558 return (error); 1559 OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */ 1560 break; 1561 case IPV6_2292RTHDR: 1562 OPTSET2292(IN6P_RTHDR); 1563 break; 1564 } 1565 break; 1566 #endif 1567 case IPV6_PKTINFO: 1568 case IPV6_HOPOPTS: 1569 case IPV6_RTHDR: 1570 case IPV6_DSTOPTS: 1571 case IPV6_RTHDRDSTOPTS: 1572 case IPV6_NEXTHOP: { 1573 /* new advanced API (RFC3542) */ 1574 void *optbuf; 1575 int optbuflen; 1576 struct ip6_pktopts **optp; 1577 1578 #ifdef RFC2292 1579 /* cannot mix with RFC2292 */ 1580 if (OPTBIT(IN6P_RFC2292)) { 1581 error = EINVAL; 1582 break; 1583 } 1584 #endif 1585 1586 optbuflen = sopt->sopt_size; 1587 optbuf = malloc(optbuflen, M_IP6OPT, M_NOWAIT); 1588 if (optbuf == NULL) { 1589 error = ENOBUFS; 1590 break; 1591 } 1592 1593 sockopt_get(sopt, optbuf, optbuflen); 1594 optp = &in6p->in6p_outputopts; 1595 error = ip6_pcbopt(optname, optbuf, optbuflen, 1596 optp, kauth_cred_get(), uproto); 1597 break; 1598 } 1599 #undef OPTSET 1600 1601 case IPV6_MULTICAST_IF: 1602 case IPV6_MULTICAST_HOPS: 1603 case IPV6_MULTICAST_LOOP: 1604 case IPV6_JOIN_GROUP: 1605 case IPV6_LEAVE_GROUP: 1606 error = ip6_setmoptions(sopt, &in6p->in6p_moptions); 1607 break; 1608 1609 case IPV6_PORTRANGE: 1610 error = sockopt_getint(sopt, &optval); 1611 if (error) 1612 break; 1613 1614 switch (optval) { 1615 case IPV6_PORTRANGE_DEFAULT: 1616 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1617 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1618 break; 1619 1620 case IPV6_PORTRANGE_HIGH: 1621 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1622 in6p->in6p_flags |= IN6P_HIGHPORT; 1623 break; 1624 1625 case IPV6_PORTRANGE_LOW: 1626 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1627 in6p->in6p_flags |= IN6P_LOWPORT; 1628 break; 1629 1630 default: 1631 error = EINVAL; 1632 break; 1633 } 1634 break; 1635 1636 1637 #if defined(FAST_IPSEC) 1638 case IPV6_IPSEC_POLICY: 1639 error = ipsec6_set_policy(in6p, optname, 1640 sopt->sopt_data, sopt->sopt_size, kauth_cred_get()); 1641 break; 1642 #endif /* IPSEC */ 1643 1644 default: 1645 error = ENOPROTOOPT; 1646 break; 1647 } 1648 break; 1649 1650 case PRCO_GETOPT: 1651 switch (optname) { 1652 #ifdef RFC2292 1653 case IPV6_2292PKTOPTIONS: 1654 /* 1655 * RFC3542 (effectively) deprecated the 1656 * semantics of the 2292-style pktoptions. 1657 * Since it was not reliable in nature (i.e., 1658 * applications had to expect the lack of some 1659 * information after all), it would make sense 1660 * to simplify this part by always returning 1661 * empty data. 1662 */ 1663 break; 1664 #endif 1665 1666 case IPV6_RECVHOPOPTS: 1667 case IPV6_RECVDSTOPTS: 1668 case IPV6_RECVRTHDRDSTOPTS: 1669 case IPV6_UNICAST_HOPS: 1670 case IPV6_RECVPKTINFO: 1671 case IPV6_RECVHOPLIMIT: 1672 case IPV6_RECVRTHDR: 1673 case IPV6_RECVPATHMTU: 1674 1675 case IPV6_FAITH: 1676 case IPV6_V6ONLY: 1677 case IPV6_PORTRANGE: 1678 case IPV6_RECVTCLASS: 1679 switch (optname) { 1680 1681 case IPV6_RECVHOPOPTS: 1682 optval = OPTBIT(IN6P_HOPOPTS); 1683 break; 1684 1685 case IPV6_RECVDSTOPTS: 1686 optval = OPTBIT(IN6P_DSTOPTS); 1687 break; 1688 1689 case IPV6_RECVRTHDRDSTOPTS: 1690 optval = OPTBIT(IN6P_RTHDRDSTOPTS); 1691 break; 1692 1693 case IPV6_UNICAST_HOPS: 1694 optval = in6p->in6p_hops; 1695 break; 1696 1697 case IPV6_RECVPKTINFO: 1698 optval = OPTBIT(IN6P_PKTINFO); 1699 break; 1700 1701 case IPV6_RECVHOPLIMIT: 1702 optval = OPTBIT(IN6P_HOPLIMIT); 1703 break; 1704 1705 case IPV6_RECVRTHDR: 1706 optval = OPTBIT(IN6P_RTHDR); 1707 break; 1708 1709 case IPV6_RECVPATHMTU: 1710 optval = OPTBIT(IN6P_MTU); 1711 break; 1712 1713 case IPV6_FAITH: 1714 optval = OPTBIT(IN6P_FAITH); 1715 break; 1716 1717 case IPV6_V6ONLY: 1718 optval = OPTBIT(IN6P_IPV6_V6ONLY); 1719 break; 1720 1721 case IPV6_PORTRANGE: 1722 { 1723 int flags; 1724 flags = in6p->in6p_flags; 1725 if (flags & IN6P_HIGHPORT) 1726 optval = IPV6_PORTRANGE_HIGH; 1727 else if (flags & IN6P_LOWPORT) 1728 optval = IPV6_PORTRANGE_LOW; 1729 else 1730 optval = 0; 1731 break; 1732 } 1733 case IPV6_RECVTCLASS: 1734 optval = OPTBIT(IN6P_TCLASS); 1735 break; 1736 1737 } 1738 if (error) 1739 break; 1740 error = sockopt_setint(sopt, optval); 1741 break; 1742 1743 case IPV6_PATHMTU: 1744 { 1745 u_long pmtu = 0; 1746 struct ip6_mtuinfo mtuinfo; 1747 struct route *ro = &in6p->in6p_route; 1748 1749 if (!(so->so_state & SS_ISCONNECTED)) 1750 return (ENOTCONN); 1751 /* 1752 * XXX: we dot not consider the case of source 1753 * routing, or optional information to specify 1754 * the outgoing interface. 1755 */ 1756 error = ip6_getpmtu(ro, NULL, NULL, 1757 &in6p->in6p_faddr, &pmtu, NULL); 1758 if (error) 1759 break; 1760 if (pmtu > IPV6_MAXPACKET) 1761 pmtu = IPV6_MAXPACKET; 1762 1763 memset(&mtuinfo, 0, sizeof(mtuinfo)); 1764 mtuinfo.ip6m_mtu = (u_int32_t)pmtu; 1765 optdata = (void *)&mtuinfo; 1766 optdatalen = sizeof(mtuinfo); 1767 if (optdatalen > MCLBYTES) 1768 return (EMSGSIZE); /* XXX */ 1769 error = sockopt_set(sopt, optdata, optdatalen); 1770 break; 1771 } 1772 1773 #ifdef RFC2292 1774 case IPV6_2292PKTINFO: 1775 case IPV6_2292HOPLIMIT: 1776 case IPV6_2292HOPOPTS: 1777 case IPV6_2292RTHDR: 1778 case IPV6_2292DSTOPTS: 1779 switch (optname) { 1780 case IPV6_2292PKTINFO: 1781 optval = OPTBIT(IN6P_PKTINFO); 1782 break; 1783 case IPV6_2292HOPLIMIT: 1784 optval = OPTBIT(IN6P_HOPLIMIT); 1785 break; 1786 case IPV6_2292HOPOPTS: 1787 optval = OPTBIT(IN6P_HOPOPTS); 1788 break; 1789 case IPV6_2292RTHDR: 1790 optval = OPTBIT(IN6P_RTHDR); 1791 break; 1792 case IPV6_2292DSTOPTS: 1793 optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); 1794 break; 1795 } 1796 error = sockopt_setint(sopt, optval); 1797 break; 1798 #endif 1799 case IPV6_PKTINFO: 1800 case IPV6_HOPOPTS: 1801 case IPV6_RTHDR: 1802 case IPV6_DSTOPTS: 1803 case IPV6_RTHDRDSTOPTS: 1804 case IPV6_NEXTHOP: 1805 case IPV6_OTCLASS: 1806 case IPV6_TCLASS: 1807 case IPV6_DONTFRAG: 1808 case IPV6_USE_MIN_MTU: 1809 error = ip6_getpcbopt(in6p->in6p_outputopts, 1810 optname, sopt); 1811 break; 1812 1813 case IPV6_MULTICAST_IF: 1814 case IPV6_MULTICAST_HOPS: 1815 case IPV6_MULTICAST_LOOP: 1816 case IPV6_JOIN_GROUP: 1817 case IPV6_LEAVE_GROUP: 1818 error = ip6_getmoptions(sopt, in6p->in6p_moptions); 1819 break; 1820 1821 #if defined(FAST_IPSEC) 1822 case IPV6_IPSEC_POLICY: 1823 { 1824 struct mbuf *m = NULL; 1825 1826 /* XXX this will return EINVAL as sopt is empty */ 1827 error = ipsec6_get_policy(in6p, sopt->sopt_data, 1828 sopt->sopt_size, &m); 1829 if (!error) 1830 error = sockopt_setmbuf(sopt, m); 1831 1832 break; 1833 } 1834 #endif /* IPSEC */ 1835 1836 default: 1837 error = ENOPROTOOPT; 1838 break; 1839 } 1840 break; 1841 } 1842 return (error); 1843 } 1844 1845 int 1846 ip6_raw_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1847 { 1848 int error = 0, optval; 1849 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); 1850 struct in6pcb *in6p = sotoin6pcb(so); 1851 int level, optname; 1852 1853 KASSERT(sopt != NULL); 1854 1855 level = sopt->sopt_level; 1856 optname = sopt->sopt_name; 1857 1858 if (level != IPPROTO_IPV6) { 1859 return ENOPROTOOPT; 1860 } 1861 1862 switch (optname) { 1863 case IPV6_CHECKSUM: 1864 /* 1865 * For ICMPv6 sockets, no modification allowed for checksum 1866 * offset, permit "no change" values to help existing apps. 1867 * 1868 * XXX RFC3542 says: "An attempt to set IPV6_CHECKSUM 1869 * for an ICMPv6 socket will fail." The current 1870 * behavior does not meet RFC3542. 1871 */ 1872 switch (op) { 1873 case PRCO_SETOPT: 1874 error = sockopt_getint(sopt, &optval); 1875 if (error) 1876 break; 1877 if ((optval % 2) != 0) { 1878 /* the API assumes even offset values */ 1879 error = EINVAL; 1880 } else if (so->so_proto->pr_protocol == 1881 IPPROTO_ICMPV6) { 1882 if (optval != icmp6off) 1883 error = EINVAL; 1884 } else 1885 in6p->in6p_cksum = optval; 1886 break; 1887 1888 case PRCO_GETOPT: 1889 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) 1890 optval = icmp6off; 1891 else 1892 optval = in6p->in6p_cksum; 1893 1894 error = sockopt_setint(sopt, optval); 1895 break; 1896 1897 default: 1898 error = EINVAL; 1899 break; 1900 } 1901 break; 1902 1903 default: 1904 error = ENOPROTOOPT; 1905 break; 1906 } 1907 1908 return (error); 1909 } 1910 1911 #ifdef RFC2292 1912 /* 1913 * Set up IP6 options in pcb for insertion in output packets or 1914 * specifying behavior of outgoing packets. 1915 */ 1916 static int 1917 ip6_pcbopts(struct ip6_pktopts **pktopt, struct socket *so, 1918 struct sockopt *sopt) 1919 { 1920 struct ip6_pktopts *opt = *pktopt; 1921 struct mbuf *m; 1922 int error = 0; 1923 1924 /* turn off any old options. */ 1925 if (opt) { 1926 #ifdef DIAGNOSTIC 1927 if (opt->ip6po_pktinfo || opt->ip6po_nexthop || 1928 opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 || 1929 opt->ip6po_rhinfo.ip6po_rhi_rthdr) 1930 printf("ip6_pcbopts: all specified options are cleared.\n"); 1931 #endif 1932 ip6_clearpktopts(opt, -1); 1933 } else { 1934 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT); 1935 if (opt == NULL) 1936 return (ENOBUFS); 1937 } 1938 *pktopt = NULL; 1939 1940 if (sopt == NULL || sopt->sopt_size == 0) { 1941 /* 1942 * Only turning off any previous options, regardless of 1943 * whether the opt is just created or given. 1944 */ 1945 free(opt, M_IP6OPT); 1946 return (0); 1947 } 1948 1949 /* set options specified by user. */ 1950 m = sockopt_getmbuf(sopt); 1951 if (m == NULL) { 1952 free(opt, M_IP6OPT); 1953 return (ENOBUFS); 1954 } 1955 1956 error = ip6_setpktopts(m, opt, NULL, kauth_cred_get(), 1957 so->so_proto->pr_protocol); 1958 m_freem(m); 1959 if (error != 0) { 1960 ip6_clearpktopts(opt, -1); /* XXX: discard all options */ 1961 free(opt, M_IP6OPT); 1962 return (error); 1963 } 1964 *pktopt = opt; 1965 return (0); 1966 } 1967 #endif 1968 1969 /* 1970 * initialize ip6_pktopts. beware that there are non-zero default values in 1971 * the struct. 1972 */ 1973 void 1974 ip6_initpktopts(struct ip6_pktopts *opt) 1975 { 1976 1977 memset(opt, 0, sizeof(*opt)); 1978 opt->ip6po_hlim = -1; /* -1 means default hop limit */ 1979 opt->ip6po_tclass = -1; /* -1 means default traffic class */ 1980 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY; 1981 } 1982 1983 #define sin6tosa(sin6) ((struct sockaddr *)(sin6)) /* XXX */ 1984 static int 1985 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt, 1986 kauth_cred_t cred, int uproto) 1987 { 1988 struct ip6_pktopts *opt; 1989 1990 if (*pktopt == NULL) { 1991 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT, 1992 M_NOWAIT); 1993 if (*pktopt == NULL) 1994 return (ENOBUFS); 1995 1996 ip6_initpktopts(*pktopt); 1997 } 1998 opt = *pktopt; 1999 2000 return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto)); 2001 } 2002 2003 static int 2004 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt) 2005 { 2006 void *optdata = NULL; 2007 int optdatalen = 0; 2008 struct ip6_ext *ip6e; 2009 int error = 0; 2010 struct in6_pktinfo null_pktinfo; 2011 int deftclass = 0, on; 2012 int defminmtu = IP6PO_MINMTU_MCASTONLY; 2013 2014 switch (optname) { 2015 case IPV6_PKTINFO: 2016 if (pktopt && pktopt->ip6po_pktinfo) 2017 optdata = (void *)pktopt->ip6po_pktinfo; 2018 else { 2019 /* XXX: we don't have to do this every time... */ 2020 memset(&null_pktinfo, 0, sizeof(null_pktinfo)); 2021 optdata = (void *)&null_pktinfo; 2022 } 2023 optdatalen = sizeof(struct in6_pktinfo); 2024 break; 2025 case IPV6_OTCLASS: 2026 /* XXX */ 2027 return (EINVAL); 2028 case IPV6_TCLASS: 2029 if (pktopt && pktopt->ip6po_tclass >= 0) 2030 optdata = (void *)&pktopt->ip6po_tclass; 2031 else 2032 optdata = (void *)&deftclass; 2033 optdatalen = sizeof(int); 2034 break; 2035 case IPV6_HOPOPTS: 2036 if (pktopt && pktopt->ip6po_hbh) { 2037 optdata = (void *)pktopt->ip6po_hbh; 2038 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh; 2039 optdatalen = (ip6e->ip6e_len + 1) << 3; 2040 } 2041 break; 2042 case IPV6_RTHDR: 2043 if (pktopt && pktopt->ip6po_rthdr) { 2044 optdata = (void *)pktopt->ip6po_rthdr; 2045 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr; 2046 optdatalen = (ip6e->ip6e_len + 1) << 3; 2047 } 2048 break; 2049 case IPV6_RTHDRDSTOPTS: 2050 if (pktopt && pktopt->ip6po_dest1) { 2051 optdata = (void *)pktopt->ip6po_dest1; 2052 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1; 2053 optdatalen = (ip6e->ip6e_len + 1) << 3; 2054 } 2055 break; 2056 case IPV6_DSTOPTS: 2057 if (pktopt && pktopt->ip6po_dest2) { 2058 optdata = (void *)pktopt->ip6po_dest2; 2059 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2; 2060 optdatalen = (ip6e->ip6e_len + 1) << 3; 2061 } 2062 break; 2063 case IPV6_NEXTHOP: 2064 if (pktopt && pktopt->ip6po_nexthop) { 2065 optdata = (void *)pktopt->ip6po_nexthop; 2066 optdatalen = pktopt->ip6po_nexthop->sa_len; 2067 } 2068 break; 2069 case IPV6_USE_MIN_MTU: 2070 if (pktopt) 2071 optdata = (void *)&pktopt->ip6po_minmtu; 2072 else 2073 optdata = (void *)&defminmtu; 2074 optdatalen = sizeof(int); 2075 break; 2076 case IPV6_DONTFRAG: 2077 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG)) 2078 on = 1; 2079 else 2080 on = 0; 2081 optdata = (void *)&on; 2082 optdatalen = sizeof(on); 2083 break; 2084 default: /* should not happen */ 2085 #ifdef DIAGNOSTIC 2086 panic("ip6_getpcbopt: unexpected option\n"); 2087 #endif 2088 return (ENOPROTOOPT); 2089 } 2090 2091 error = sockopt_set(sopt, optdata, optdatalen); 2092 2093 return (error); 2094 } 2095 2096 void 2097 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname) 2098 { 2099 if (optname == -1 || optname == IPV6_PKTINFO) { 2100 if (pktopt->ip6po_pktinfo) 2101 free(pktopt->ip6po_pktinfo, M_IP6OPT); 2102 pktopt->ip6po_pktinfo = NULL; 2103 } 2104 if (optname == -1 || optname == IPV6_HOPLIMIT) 2105 pktopt->ip6po_hlim = -1; 2106 if (optname == -1 || optname == IPV6_TCLASS) 2107 pktopt->ip6po_tclass = -1; 2108 if (optname == -1 || optname == IPV6_NEXTHOP) { 2109 rtcache_free(&pktopt->ip6po_nextroute); 2110 if (pktopt->ip6po_nexthop) 2111 free(pktopt->ip6po_nexthop, M_IP6OPT); 2112 pktopt->ip6po_nexthop = NULL; 2113 } 2114 if (optname == -1 || optname == IPV6_HOPOPTS) { 2115 if (pktopt->ip6po_hbh) 2116 free(pktopt->ip6po_hbh, M_IP6OPT); 2117 pktopt->ip6po_hbh = NULL; 2118 } 2119 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) { 2120 if (pktopt->ip6po_dest1) 2121 free(pktopt->ip6po_dest1, M_IP6OPT); 2122 pktopt->ip6po_dest1 = NULL; 2123 } 2124 if (optname == -1 || optname == IPV6_RTHDR) { 2125 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr) 2126 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT); 2127 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL; 2128 rtcache_free(&pktopt->ip6po_route); 2129 } 2130 if (optname == -1 || optname == IPV6_DSTOPTS) { 2131 if (pktopt->ip6po_dest2) 2132 free(pktopt->ip6po_dest2, M_IP6OPT); 2133 pktopt->ip6po_dest2 = NULL; 2134 } 2135 } 2136 2137 #define PKTOPT_EXTHDRCPY(type) \ 2138 do { \ 2139 if (src->type) { \ 2140 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\ 2141 dst->type = malloc(hlen, M_IP6OPT, canwait); \ 2142 if (dst->type == NULL) \ 2143 goto bad; \ 2144 memcpy(dst->type, src->type, hlen); \ 2145 } \ 2146 } while (/*CONSTCOND*/ 0) 2147 2148 static int 2149 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait) 2150 { 2151 dst->ip6po_hlim = src->ip6po_hlim; 2152 dst->ip6po_tclass = src->ip6po_tclass; 2153 dst->ip6po_flags = src->ip6po_flags; 2154 if (src->ip6po_pktinfo) { 2155 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo), 2156 M_IP6OPT, canwait); 2157 if (dst->ip6po_pktinfo == NULL) 2158 goto bad; 2159 *dst->ip6po_pktinfo = *src->ip6po_pktinfo; 2160 } 2161 if (src->ip6po_nexthop) { 2162 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len, 2163 M_IP6OPT, canwait); 2164 if (dst->ip6po_nexthop == NULL) 2165 goto bad; 2166 memcpy(dst->ip6po_nexthop, src->ip6po_nexthop, 2167 src->ip6po_nexthop->sa_len); 2168 } 2169 PKTOPT_EXTHDRCPY(ip6po_hbh); 2170 PKTOPT_EXTHDRCPY(ip6po_dest1); 2171 PKTOPT_EXTHDRCPY(ip6po_dest2); 2172 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */ 2173 return (0); 2174 2175 bad: 2176 if (dst->ip6po_pktinfo) free(dst->ip6po_pktinfo, M_IP6OPT); 2177 if (dst->ip6po_nexthop) free(dst->ip6po_nexthop, M_IP6OPT); 2178 if (dst->ip6po_hbh) free(dst->ip6po_hbh, M_IP6OPT); 2179 if (dst->ip6po_dest1) free(dst->ip6po_dest1, M_IP6OPT); 2180 if (dst->ip6po_dest2) free(dst->ip6po_dest2, M_IP6OPT); 2181 if (dst->ip6po_rthdr) free(dst->ip6po_rthdr, M_IP6OPT); 2182 2183 return (ENOBUFS); 2184 } 2185 #undef PKTOPT_EXTHDRCPY 2186 2187 struct ip6_pktopts * 2188 ip6_copypktopts(struct ip6_pktopts *src, int canwait) 2189 { 2190 int error; 2191 struct ip6_pktopts *dst; 2192 2193 dst = malloc(sizeof(*dst), M_IP6OPT, canwait); 2194 if (dst == NULL) 2195 return (NULL); 2196 ip6_initpktopts(dst); 2197 2198 if ((error = copypktopts(dst, src, canwait)) != 0) { 2199 free(dst, M_IP6OPT); 2200 return (NULL); 2201 } 2202 2203 return (dst); 2204 } 2205 2206 void 2207 ip6_freepcbopts(struct ip6_pktopts *pktopt) 2208 { 2209 if (pktopt == NULL) 2210 return; 2211 2212 ip6_clearpktopts(pktopt, -1); 2213 2214 free(pktopt, M_IP6OPT); 2215 } 2216 2217 /* 2218 * Set the IP6 multicast options in response to user setsockopt(). 2219 */ 2220 static int 2221 ip6_setmoptions(const struct sockopt *sopt, struct ip6_moptions **im6op) 2222 { 2223 int error = 0; 2224 u_int loop, ifindex; 2225 struct ipv6_mreq mreq; 2226 struct ifnet *ifp; 2227 struct ip6_moptions *im6o = *im6op; 2228 struct route ro; 2229 struct in6_multi_mship *imm; 2230 struct lwp *l = curlwp; /* XXX */ 2231 2232 if (im6o == NULL) { 2233 /* 2234 * No multicast option buffer attached to the pcb; 2235 * allocate one and initialize to default values. 2236 */ 2237 im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_NOWAIT); 2238 if (im6o == NULL) 2239 return (ENOBUFS); 2240 2241 *im6op = im6o; 2242 im6o->im6o_multicast_ifp = NULL; 2243 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 2244 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP; 2245 LIST_INIT(&im6o->im6o_memberships); 2246 } 2247 2248 switch (sopt->sopt_name) { 2249 2250 case IPV6_MULTICAST_IF: 2251 /* 2252 * Select the interface for outgoing multicast packets. 2253 */ 2254 error = sockopt_get(sopt, &ifindex, sizeof(ifindex)); 2255 if (error != 0) 2256 break; 2257 2258 if (ifindex != 0) { 2259 if (if_indexlim <= ifindex || !ifindex2ifnet[ifindex]) { 2260 error = ENXIO; /* XXX EINVAL? */ 2261 break; 2262 } 2263 ifp = ifindex2ifnet[ifindex]; 2264 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 2265 error = EADDRNOTAVAIL; 2266 break; 2267 } 2268 } else 2269 ifp = NULL; 2270 im6o->im6o_multicast_ifp = ifp; 2271 break; 2272 2273 case IPV6_MULTICAST_HOPS: 2274 { 2275 /* 2276 * Set the IP6 hoplimit for outgoing multicast packets. 2277 */ 2278 int optval; 2279 2280 error = sockopt_getint(sopt, &optval); 2281 if (error != 0) 2282 break; 2283 2284 if (optval < -1 || optval >= 256) 2285 error = EINVAL; 2286 else if (optval == -1) 2287 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 2288 else 2289 im6o->im6o_multicast_hlim = optval; 2290 break; 2291 } 2292 2293 case IPV6_MULTICAST_LOOP: 2294 /* 2295 * Set the loopback flag for outgoing multicast packets. 2296 * Must be zero or one. 2297 */ 2298 error = sockopt_get(sopt, &loop, sizeof(loop)); 2299 if (error != 0) 2300 break; 2301 if (loop > 1) { 2302 error = EINVAL; 2303 break; 2304 } 2305 im6o->im6o_multicast_loop = loop; 2306 break; 2307 2308 case IPV6_JOIN_GROUP: 2309 /* 2310 * Add a multicast group membership. 2311 * Group must be a valid IP6 multicast address. 2312 */ 2313 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 2314 if (error != 0) 2315 break; 2316 2317 if (IN6_IS_ADDR_UNSPECIFIED(&mreq.ipv6mr_multiaddr)) { 2318 /* 2319 * We use the unspecified address to specify to accept 2320 * all multicast addresses. Only super user is allowed 2321 * to do this. 2322 */ 2323 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_IPV6, 2324 KAUTH_REQ_NETWORK_IPV6_JOIN_MULTICAST, NULL, NULL, NULL)) 2325 { 2326 error = EACCES; 2327 break; 2328 } 2329 } else if (!IN6_IS_ADDR_MULTICAST(&mreq.ipv6mr_multiaddr)) { 2330 error = EINVAL; 2331 break; 2332 } 2333 2334 /* 2335 * If no interface was explicitly specified, choose an 2336 * appropriate one according to the given multicast address. 2337 */ 2338 if (mreq.ipv6mr_interface == 0) { 2339 struct rtentry *rt; 2340 union { 2341 struct sockaddr dst; 2342 struct sockaddr_in6 dst6; 2343 } u; 2344 2345 /* 2346 * Look up the routing table for the 2347 * address, and choose the outgoing interface. 2348 * XXX: is it a good approach? 2349 */ 2350 memset(&ro, 0, sizeof(ro)); 2351 sockaddr_in6_init(&u.dst6, &mreq.ipv6mr_multiaddr, 0, 2352 0, 0); 2353 rtcache_setdst(&ro, &u.dst); 2354 ifp = (rt = rtcache_init(&ro)) != NULL ? rt->rt_ifp 2355 : NULL; 2356 rtcache_free(&ro); 2357 } else { 2358 /* 2359 * If the interface is specified, validate it. 2360 */ 2361 if (if_indexlim <= mreq.ipv6mr_interface || 2362 !ifindex2ifnet[mreq.ipv6mr_interface]) { 2363 error = ENXIO; /* XXX EINVAL? */ 2364 break; 2365 } 2366 ifp = ifindex2ifnet[mreq.ipv6mr_interface]; 2367 } 2368 2369 /* 2370 * See if we found an interface, and confirm that it 2371 * supports multicast 2372 */ 2373 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 2374 error = EADDRNOTAVAIL; 2375 break; 2376 } 2377 2378 if (in6_setscope(&mreq.ipv6mr_multiaddr, ifp, NULL)) { 2379 error = EADDRNOTAVAIL; /* XXX: should not happen */ 2380 break; 2381 } 2382 2383 /* 2384 * See if the membership already exists. 2385 */ 2386 for (imm = im6o->im6o_memberships.lh_first; 2387 imm != NULL; imm = imm->i6mm_chain.le_next) 2388 if (imm->i6mm_maddr->in6m_ifp == ifp && 2389 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2390 &mreq.ipv6mr_multiaddr)) 2391 break; 2392 if (imm != NULL) { 2393 error = EADDRINUSE; 2394 break; 2395 } 2396 /* 2397 * Everything looks good; add a new record to the multicast 2398 * address list for the given interface. 2399 */ 2400 imm = in6_joingroup(ifp, &mreq.ipv6mr_multiaddr, &error, 0); 2401 if (imm == NULL) 2402 break; 2403 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); 2404 break; 2405 2406 case IPV6_LEAVE_GROUP: 2407 /* 2408 * Drop a multicast group membership. 2409 * Group must be a valid IP6 multicast address. 2410 */ 2411 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 2412 if (error != 0) 2413 break; 2414 2415 /* 2416 * If an interface address was specified, get a pointer 2417 * to its ifnet structure. 2418 */ 2419 if (mreq.ipv6mr_interface != 0) { 2420 if (if_indexlim <= mreq.ipv6mr_interface || 2421 !ifindex2ifnet[mreq.ipv6mr_interface]) { 2422 error = ENXIO; /* XXX EINVAL? */ 2423 break; 2424 } 2425 ifp = ifindex2ifnet[mreq.ipv6mr_interface]; 2426 } else 2427 ifp = NULL; 2428 2429 /* Fill in the scope zone ID */ 2430 if (ifp) { 2431 if (in6_setscope(&mreq.ipv6mr_multiaddr, ifp, NULL)) { 2432 /* XXX: should not happen */ 2433 error = EADDRNOTAVAIL; 2434 break; 2435 } 2436 } else if (mreq.ipv6mr_interface != 0) { 2437 /* 2438 * XXX: This case would happens when the (positive) 2439 * index is in the valid range, but the corresponding 2440 * interface has been detached dynamically. The above 2441 * check probably avoids such case to happen here, but 2442 * we check it explicitly for safety. 2443 */ 2444 error = EADDRNOTAVAIL; 2445 break; 2446 } else { /* ipv6mr_interface == 0 */ 2447 struct sockaddr_in6 sa6_mc; 2448 2449 /* 2450 * The API spec says as follows: 2451 * If the interface index is specified as 0, the 2452 * system may choose a multicast group membership to 2453 * drop by matching the multicast address only. 2454 * On the other hand, we cannot disambiguate the scope 2455 * zone unless an interface is provided. Thus, we 2456 * check if there's ambiguity with the default scope 2457 * zone as the last resort. 2458 */ 2459 sockaddr_in6_init(&sa6_mc, &mreq.ipv6mr_multiaddr, 2460 0, 0, 0); 2461 error = sa6_embedscope(&sa6_mc, ip6_use_defzone); 2462 if (error != 0) 2463 break; 2464 mreq.ipv6mr_multiaddr = sa6_mc.sin6_addr; 2465 } 2466 2467 /* 2468 * Find the membership in the membership list. 2469 */ 2470 for (imm = im6o->im6o_memberships.lh_first; 2471 imm != NULL; imm = imm->i6mm_chain.le_next) { 2472 if ((ifp == NULL || imm->i6mm_maddr->in6m_ifp == ifp) && 2473 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2474 &mreq.ipv6mr_multiaddr)) 2475 break; 2476 } 2477 if (imm == NULL) { 2478 /* Unable to resolve interface */ 2479 error = EADDRNOTAVAIL; 2480 break; 2481 } 2482 /* 2483 * Give up the multicast address record to which the 2484 * membership points. 2485 */ 2486 LIST_REMOVE(imm, i6mm_chain); 2487 in6_leavegroup(imm); 2488 break; 2489 2490 default: 2491 error = EOPNOTSUPP; 2492 break; 2493 } 2494 2495 /* 2496 * If all options have default values, no need to keep the mbuf. 2497 */ 2498 if (im6o->im6o_multicast_ifp == NULL && 2499 im6o->im6o_multicast_hlim == ip6_defmcasthlim && 2500 im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP && 2501 im6o->im6o_memberships.lh_first == NULL) { 2502 free(*im6op, M_IPMOPTS); 2503 *im6op = NULL; 2504 } 2505 2506 return (error); 2507 } 2508 2509 /* 2510 * Return the IP6 multicast options in response to user getsockopt(). 2511 */ 2512 static int 2513 ip6_getmoptions(struct sockopt *sopt, struct ip6_moptions *im6o) 2514 { 2515 u_int optval; 2516 int error; 2517 2518 switch (sopt->sopt_name) { 2519 case IPV6_MULTICAST_IF: 2520 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL) 2521 optval = 0; 2522 else 2523 optval = im6o->im6o_multicast_ifp->if_index; 2524 2525 error = sockopt_set(sopt, &optval, sizeof(optval)); 2526 break; 2527 2528 case IPV6_MULTICAST_HOPS: 2529 if (im6o == NULL) 2530 optval = ip6_defmcasthlim; 2531 else 2532 optval = im6o->im6o_multicast_hlim; 2533 2534 error = sockopt_set(sopt, &optval, sizeof(optval)); 2535 break; 2536 2537 case IPV6_MULTICAST_LOOP: 2538 if (im6o == NULL) 2539 optval = ip6_defmcasthlim; 2540 else 2541 optval = im6o->im6o_multicast_loop; 2542 2543 error = sockopt_set(sopt, &optval, sizeof(optval)); 2544 break; 2545 2546 default: 2547 error = EOPNOTSUPP; 2548 } 2549 2550 return (error); 2551 } 2552 2553 /* 2554 * Discard the IP6 multicast options. 2555 */ 2556 void 2557 ip6_freemoptions(struct ip6_moptions *im6o) 2558 { 2559 struct in6_multi_mship *imm; 2560 2561 if (im6o == NULL) 2562 return; 2563 2564 while ((imm = im6o->im6o_memberships.lh_first) != NULL) { 2565 LIST_REMOVE(imm, i6mm_chain); 2566 in6_leavegroup(imm); 2567 } 2568 free(im6o, M_IPMOPTS); 2569 } 2570 2571 /* 2572 * Set IPv6 outgoing packet options based on advanced API. 2573 */ 2574 int 2575 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt, 2576 struct ip6_pktopts *stickyopt, kauth_cred_t cred, int uproto) 2577 { 2578 struct cmsghdr *cm = 0; 2579 2580 if (control == NULL || opt == NULL) 2581 return (EINVAL); 2582 2583 ip6_initpktopts(opt); 2584 if (stickyopt) { 2585 int error; 2586 2587 /* 2588 * If stickyopt is provided, make a local copy of the options 2589 * for this particular packet, then override them by ancillary 2590 * objects. 2591 * XXX: copypktopts() does not copy the cached route to a next 2592 * hop (if any). This is not very good in terms of efficiency, 2593 * but we can allow this since this option should be rarely 2594 * used. 2595 */ 2596 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0) 2597 return (error); 2598 } 2599 2600 /* 2601 * XXX: Currently, we assume all the optional information is stored 2602 * in a single mbuf. 2603 */ 2604 if (control->m_next) 2605 return (EINVAL); 2606 2607 /* XXX if cm->cmsg_len is not aligned, control->m_len can become <0 */ 2608 for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len), 2609 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 2610 int error; 2611 2612 if (control->m_len < CMSG_LEN(0)) 2613 return (EINVAL); 2614 2615 cm = mtod(control, struct cmsghdr *); 2616 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len) 2617 return (EINVAL); 2618 if (cm->cmsg_level != IPPROTO_IPV6) 2619 continue; 2620 2621 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm), 2622 cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto); 2623 if (error) 2624 return (error); 2625 } 2626 2627 return (0); 2628 } 2629 2630 /* 2631 * Set a particular packet option, as a sticky option or an ancillary data 2632 * item. "len" can be 0 only when it's a sticky option. 2633 * We have 4 cases of combination of "sticky" and "cmsg": 2634 * "sticky=0, cmsg=0": impossible 2635 * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data 2636 * "sticky=1, cmsg=0": RFC3542 socket option 2637 * "sticky=1, cmsg=1": RFC2292 socket option 2638 */ 2639 static int 2640 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt, 2641 kauth_cred_t cred, int sticky, int cmsg, int uproto) 2642 { 2643 int minmtupolicy; 2644 int error; 2645 2646 if (!sticky && !cmsg) { 2647 #ifdef DIAGNOSTIC 2648 printf("ip6_setpktopt: impossible case\n"); 2649 #endif 2650 return (EINVAL); 2651 } 2652 2653 /* 2654 * IPV6_2292xxx is for backward compatibility to RFC2292, and should 2655 * not be specified in the context of RFC3542. Conversely, 2656 * RFC3542 types should not be specified in the context of RFC2292. 2657 */ 2658 if (!cmsg) { 2659 switch (optname) { 2660 case IPV6_2292PKTINFO: 2661 case IPV6_2292HOPLIMIT: 2662 case IPV6_2292NEXTHOP: 2663 case IPV6_2292HOPOPTS: 2664 case IPV6_2292DSTOPTS: 2665 case IPV6_2292RTHDR: 2666 case IPV6_2292PKTOPTIONS: 2667 return (ENOPROTOOPT); 2668 } 2669 } 2670 if (sticky && cmsg) { 2671 switch (optname) { 2672 case IPV6_PKTINFO: 2673 case IPV6_HOPLIMIT: 2674 case IPV6_NEXTHOP: 2675 case IPV6_HOPOPTS: 2676 case IPV6_DSTOPTS: 2677 case IPV6_RTHDRDSTOPTS: 2678 case IPV6_RTHDR: 2679 case IPV6_USE_MIN_MTU: 2680 case IPV6_DONTFRAG: 2681 case IPV6_OTCLASS: 2682 case IPV6_TCLASS: 2683 return (ENOPROTOOPT); 2684 } 2685 } 2686 2687 switch (optname) { 2688 #ifdef RFC2292 2689 case IPV6_2292PKTINFO: 2690 #endif 2691 case IPV6_PKTINFO: 2692 { 2693 struct ifnet *ifp = NULL; 2694 struct in6_pktinfo *pktinfo; 2695 2696 if (len != sizeof(struct in6_pktinfo)) 2697 return (EINVAL); 2698 2699 pktinfo = (struct in6_pktinfo *)buf; 2700 2701 /* 2702 * An application can clear any sticky IPV6_PKTINFO option by 2703 * doing a "regular" setsockopt with ipi6_addr being 2704 * in6addr_any and ipi6_ifindex being zero. 2705 * [RFC 3542, Section 6] 2706 */ 2707 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo && 2708 pktinfo->ipi6_ifindex == 0 && 2709 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2710 ip6_clearpktopts(opt, optname); 2711 break; 2712 } 2713 2714 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO && 2715 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2716 return (EINVAL); 2717 } 2718 2719 /* validate the interface index if specified. */ 2720 if (pktinfo->ipi6_ifindex >= if_indexlim) { 2721 return (ENXIO); 2722 } 2723 if (pktinfo->ipi6_ifindex) { 2724 ifp = ifindex2ifnet[pktinfo->ipi6_ifindex]; 2725 if (ifp == NULL) 2726 return (ENXIO); 2727 } 2728 2729 /* 2730 * We store the address anyway, and let in6_selectsrc() 2731 * validate the specified address. This is because ipi6_addr 2732 * may not have enough information about its scope zone, and 2733 * we may need additional information (such as outgoing 2734 * interface or the scope zone of a destination address) to 2735 * disambiguate the scope. 2736 * XXX: the delay of the validation may confuse the 2737 * application when it is used as a sticky option. 2738 */ 2739 if (opt->ip6po_pktinfo == NULL) { 2740 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo), 2741 M_IP6OPT, M_NOWAIT); 2742 if (opt->ip6po_pktinfo == NULL) 2743 return (ENOBUFS); 2744 } 2745 memcpy(opt->ip6po_pktinfo, pktinfo, sizeof(*pktinfo)); 2746 break; 2747 } 2748 2749 #ifdef RFC2292 2750 case IPV6_2292HOPLIMIT: 2751 #endif 2752 case IPV6_HOPLIMIT: 2753 { 2754 int *hlimp; 2755 2756 /* 2757 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT 2758 * to simplify the ordering among hoplimit options. 2759 */ 2760 if (optname == IPV6_HOPLIMIT && sticky) 2761 return (ENOPROTOOPT); 2762 2763 if (len != sizeof(int)) 2764 return (EINVAL); 2765 hlimp = (int *)buf; 2766 if (*hlimp < -1 || *hlimp > 255) 2767 return (EINVAL); 2768 2769 opt->ip6po_hlim = *hlimp; 2770 break; 2771 } 2772 2773 case IPV6_OTCLASS: 2774 if (len != sizeof(u_int8_t)) 2775 return (EINVAL); 2776 2777 opt->ip6po_tclass = *(u_int8_t *)buf; 2778 break; 2779 2780 case IPV6_TCLASS: 2781 { 2782 int tclass; 2783 2784 if (len != sizeof(int)) 2785 return (EINVAL); 2786 tclass = *(int *)buf; 2787 if (tclass < -1 || tclass > 255) 2788 return (EINVAL); 2789 2790 opt->ip6po_tclass = tclass; 2791 break; 2792 } 2793 2794 #ifdef RFC2292 2795 case IPV6_2292NEXTHOP: 2796 #endif 2797 case IPV6_NEXTHOP: 2798 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2799 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2800 if (error) 2801 return (error); 2802 2803 if (len == 0) { /* just remove the option */ 2804 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2805 break; 2806 } 2807 2808 /* check if cmsg_len is large enough for sa_len */ 2809 if (len < sizeof(struct sockaddr) || len < *buf) 2810 return (EINVAL); 2811 2812 switch (((struct sockaddr *)buf)->sa_family) { 2813 case AF_INET6: 2814 { 2815 struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf; 2816 2817 if (sa6->sin6_len != sizeof(struct sockaddr_in6)) 2818 return (EINVAL); 2819 2820 if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) || 2821 IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 2822 return (EINVAL); 2823 } 2824 if ((error = sa6_embedscope(sa6, ip6_use_defzone)) 2825 != 0) { 2826 return (error); 2827 } 2828 break; 2829 } 2830 case AF_LINK: /* eventually be supported? */ 2831 default: 2832 return (EAFNOSUPPORT); 2833 } 2834 2835 /* turn off the previous option, then set the new option. */ 2836 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2837 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT); 2838 if (opt->ip6po_nexthop == NULL) 2839 return (ENOBUFS); 2840 memcpy(opt->ip6po_nexthop, buf, *buf); 2841 break; 2842 2843 #ifdef RFC2292 2844 case IPV6_2292HOPOPTS: 2845 #endif 2846 case IPV6_HOPOPTS: 2847 { 2848 struct ip6_hbh *hbh; 2849 int hbhlen; 2850 2851 /* 2852 * XXX: We don't allow a non-privileged user to set ANY HbH 2853 * options, since per-option restriction has too much 2854 * overhead. 2855 */ 2856 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2857 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2858 if (error) 2859 return (error); 2860 2861 if (len == 0) { 2862 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2863 break; /* just remove the option */ 2864 } 2865 2866 /* message length validation */ 2867 if (len < sizeof(struct ip6_hbh)) 2868 return (EINVAL); 2869 hbh = (struct ip6_hbh *)buf; 2870 hbhlen = (hbh->ip6h_len + 1) << 3; 2871 if (len != hbhlen) 2872 return (EINVAL); 2873 2874 /* turn off the previous option, then set the new option. */ 2875 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2876 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT); 2877 if (opt->ip6po_hbh == NULL) 2878 return (ENOBUFS); 2879 memcpy(opt->ip6po_hbh, hbh, hbhlen); 2880 2881 break; 2882 } 2883 2884 #ifdef RFC2292 2885 case IPV6_2292DSTOPTS: 2886 #endif 2887 case IPV6_DSTOPTS: 2888 case IPV6_RTHDRDSTOPTS: 2889 { 2890 struct ip6_dest *dest, **newdest = NULL; 2891 int destlen; 2892 2893 /* XXX: see the comment for IPV6_HOPOPTS */ 2894 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPV6, 2895 KAUTH_REQ_NETWORK_IPV6_HOPBYHOP, NULL, NULL, NULL); 2896 if (error) 2897 return (error); 2898 2899 if (len == 0) { 2900 ip6_clearpktopts(opt, optname); 2901 break; /* just remove the option */ 2902 } 2903 2904 /* message length validation */ 2905 if (len < sizeof(struct ip6_dest)) 2906 return (EINVAL); 2907 dest = (struct ip6_dest *)buf; 2908 destlen = (dest->ip6d_len + 1) << 3; 2909 if (len != destlen) 2910 return (EINVAL); 2911 /* 2912 * Determine the position that the destination options header 2913 * should be inserted; before or after the routing header. 2914 */ 2915 switch (optname) { 2916 case IPV6_2292DSTOPTS: 2917 /* 2918 * The old advanced API is ambiguous on this point. 2919 * Our approach is to determine the position based 2920 * according to the existence of a routing header. 2921 * Note, however, that this depends on the order of the 2922 * extension headers in the ancillary data; the 1st 2923 * part of the destination options header must appear 2924 * before the routing header in the ancillary data, 2925 * too. 2926 * RFC3542 solved the ambiguity by introducing 2927 * separate ancillary data or option types. 2928 */ 2929 if (opt->ip6po_rthdr == NULL) 2930 newdest = &opt->ip6po_dest1; 2931 else 2932 newdest = &opt->ip6po_dest2; 2933 break; 2934 case IPV6_RTHDRDSTOPTS: 2935 newdest = &opt->ip6po_dest1; 2936 break; 2937 case IPV6_DSTOPTS: 2938 newdest = &opt->ip6po_dest2; 2939 break; 2940 } 2941 2942 /* turn off the previous option, then set the new option. */ 2943 ip6_clearpktopts(opt, optname); 2944 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT); 2945 if (*newdest == NULL) 2946 return (ENOBUFS); 2947 memcpy(*newdest, dest, destlen); 2948 2949 break; 2950 } 2951 2952 #ifdef RFC2292 2953 case IPV6_2292RTHDR: 2954 #endif 2955 case IPV6_RTHDR: 2956 { 2957 struct ip6_rthdr *rth; 2958 int rthlen; 2959 2960 if (len == 0) { 2961 ip6_clearpktopts(opt, IPV6_RTHDR); 2962 break; /* just remove the option */ 2963 } 2964 2965 /* message length validation */ 2966 if (len < sizeof(struct ip6_rthdr)) 2967 return (EINVAL); 2968 rth = (struct ip6_rthdr *)buf; 2969 rthlen = (rth->ip6r_len + 1) << 3; 2970 if (len != rthlen) 2971 return (EINVAL); 2972 switch (rth->ip6r_type) { 2973 case IPV6_RTHDR_TYPE_0: 2974 if (rth->ip6r_len == 0) /* must contain one addr */ 2975 return (EINVAL); 2976 if (rth->ip6r_len % 2) /* length must be even */ 2977 return (EINVAL); 2978 if (rth->ip6r_len / 2 != rth->ip6r_segleft) 2979 return (EINVAL); 2980 break; 2981 default: 2982 return (EINVAL); /* not supported */ 2983 } 2984 /* turn off the previous option */ 2985 ip6_clearpktopts(opt, IPV6_RTHDR); 2986 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT); 2987 if (opt->ip6po_rthdr == NULL) 2988 return (ENOBUFS); 2989 memcpy(opt->ip6po_rthdr, rth, rthlen); 2990 break; 2991 } 2992 2993 case IPV6_USE_MIN_MTU: 2994 if (len != sizeof(int)) 2995 return (EINVAL); 2996 minmtupolicy = *(int *)buf; 2997 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY && 2998 minmtupolicy != IP6PO_MINMTU_DISABLE && 2999 minmtupolicy != IP6PO_MINMTU_ALL) { 3000 return (EINVAL); 3001 } 3002 opt->ip6po_minmtu = minmtupolicy; 3003 break; 3004 3005 case IPV6_DONTFRAG: 3006 if (len != sizeof(int)) 3007 return (EINVAL); 3008 3009 if (uproto == IPPROTO_TCP || *(int *)buf == 0) { 3010 /* 3011 * we ignore this option for TCP sockets. 3012 * (RFC3542 leaves this case unspecified.) 3013 */ 3014 opt->ip6po_flags &= ~IP6PO_DONTFRAG; 3015 } else 3016 opt->ip6po_flags |= IP6PO_DONTFRAG; 3017 break; 3018 3019 default: 3020 return (ENOPROTOOPT); 3021 } /* end of switch */ 3022 3023 return (0); 3024 } 3025 3026 /* 3027 * Routine called from ip6_output() to loop back a copy of an IP6 multicast 3028 * packet to the input queue of a specified interface. Note that this 3029 * calls the output routine of the loopback "driver", but with an interface 3030 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 3031 */ 3032 void 3033 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, 3034 const struct sockaddr_in6 *dst) 3035 { 3036 struct mbuf *copym; 3037 struct ip6_hdr *ip6; 3038 3039 copym = m_copy(m, 0, M_COPYALL); 3040 if (copym == NULL) 3041 return; 3042 3043 /* 3044 * Make sure to deep-copy IPv6 header portion in case the data 3045 * is in an mbuf cluster, so that we can safely override the IPv6 3046 * header portion later. 3047 */ 3048 if ((copym->m_flags & M_EXT) != 0 || 3049 copym->m_len < sizeof(struct ip6_hdr)) { 3050 copym = m_pullup(copym, sizeof(struct ip6_hdr)); 3051 if (copym == NULL) 3052 return; 3053 } 3054 3055 #ifdef DIAGNOSTIC 3056 if (copym->m_len < sizeof(*ip6)) { 3057 m_freem(copym); 3058 return; 3059 } 3060 #endif 3061 3062 ip6 = mtod(copym, struct ip6_hdr *); 3063 /* 3064 * clear embedded scope identifiers if necessary. 3065 * in6_clearscope will touch the addresses only when necessary. 3066 */ 3067 in6_clearscope(&ip6->ip6_src); 3068 in6_clearscope(&ip6->ip6_dst); 3069 3070 (void)looutput(ifp, copym, (const struct sockaddr *)dst, NULL); 3071 } 3072 3073 /* 3074 * Chop IPv6 header off from the payload. 3075 */ 3076 static int 3077 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs) 3078 { 3079 struct mbuf *mh; 3080 struct ip6_hdr *ip6; 3081 3082 ip6 = mtod(m, struct ip6_hdr *); 3083 if (m->m_len > sizeof(*ip6)) { 3084 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 3085 if (mh == 0) { 3086 m_freem(m); 3087 return ENOBUFS; 3088 } 3089 M_MOVE_PKTHDR(mh, m); 3090 MH_ALIGN(mh, sizeof(*ip6)); 3091 m->m_len -= sizeof(*ip6); 3092 m->m_data += sizeof(*ip6); 3093 mh->m_next = m; 3094 m = mh; 3095 m->m_len = sizeof(*ip6); 3096 bcopy((void *)ip6, mtod(m, void *), sizeof(*ip6)); 3097 } 3098 exthdrs->ip6e_ip6 = m; 3099 return 0; 3100 } 3101 3102 /* 3103 * Compute IPv6 extension header length. 3104 */ 3105 int 3106 ip6_optlen(struct in6pcb *in6p) 3107 { 3108 int len; 3109 3110 if (!in6p->in6p_outputopts) 3111 return 0; 3112 3113 len = 0; 3114 #define elen(x) \ 3115 (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0) 3116 3117 len += elen(in6p->in6p_outputopts->ip6po_hbh); 3118 len += elen(in6p->in6p_outputopts->ip6po_dest1); 3119 len += elen(in6p->in6p_outputopts->ip6po_rthdr); 3120 len += elen(in6p->in6p_outputopts->ip6po_dest2); 3121 return len; 3122 #undef elen 3123 } 3124