1 /* $OpenBSD: ip6_output.c,v 1.272 2022/11/12 02:50:59 kn 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 "pf.h" 65 66 #include <sys/param.h> 67 #include <sys/malloc.h> 68 #include <sys/mbuf.h> 69 #include <sys/errno.h> 70 #include <sys/protosw.h> 71 #include <sys/socket.h> 72 #include <sys/socketvar.h> 73 #include <sys/proc.h> 74 #include <sys/systm.h> 75 76 #include <net/if.h> 77 #include <net/if_var.h> 78 #include <net/if_enc.h> 79 #include <net/route.h> 80 81 #include <netinet/in.h> 82 #include <netinet/ip.h> 83 #include <netinet/in_pcb.h> 84 #include <netinet/udp.h> 85 #include <netinet/tcp.h> 86 87 #include <netinet/ip_var.h> 88 #include <netinet/tcp_timer.h> 89 #include <netinet/tcp_var.h> 90 #include <netinet/udp_var.h> 91 92 #include <netinet6/in6_var.h> 93 #include <netinet/ip6.h> 94 #include <netinet/icmp6.h> 95 #include <netinet6/ip6_var.h> 96 #include <netinet6/nd6.h> 97 98 #include <crypto/idgen.h> 99 100 #if NPF > 0 101 #include <net/pfvar.h> 102 #endif 103 104 #ifdef IPSEC 105 #include <netinet/ip_ipsp.h> 106 #include <netinet/ip_ah.h> 107 #include <netinet/ip_esp.h> 108 109 #ifdef ENCDEBUG 110 #define DPRINTF(fmt, args...) \ 111 do { \ 112 if (encdebug) \ 113 printf("%s: " fmt "\n", __func__, ## args); \ 114 } while (0) 115 #else 116 #define DPRINTF(fmt, args...) \ 117 do { } while (0) 118 #endif 119 #endif /* IPSEC */ 120 121 struct ip6_exthdrs { 122 struct mbuf *ip6e_ip6; 123 struct mbuf *ip6e_hbh; 124 struct mbuf *ip6e_dest1; 125 struct mbuf *ip6e_rthdr; 126 struct mbuf *ip6e_dest2; 127 }; 128 129 int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, int, int); 130 int ip6_getpcbopt(struct ip6_pktopts *, int, struct mbuf *); 131 int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, int, int, int); 132 int ip6_setmoptions(int, struct ip6_moptions **, struct mbuf *, unsigned int); 133 int ip6_getmoptions(int, struct ip6_moptions *, struct mbuf *); 134 int ip6_copyexthdr(struct mbuf **, caddr_t, int); 135 int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int, 136 struct ip6_frag **); 137 int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t); 138 int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *); 139 int ip6_getpmtu(struct rtentry *, struct ifnet *, u_long *); 140 int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *); 141 static __inline u_int16_t __attribute__((__unused__)) 142 in6_cksum_phdr(const struct in6_addr *, const struct in6_addr *, 143 u_int32_t, u_int32_t); 144 void in6_delayed_cksum(struct mbuf *, u_int8_t); 145 146 int ip6_output_ipsec_pmtu_update(struct tdb *, struct route_in6 *, 147 struct in6_addr *, int, int, int); 148 149 /* Context for non-repeating IDs */ 150 struct idgen32_ctx ip6_id_ctx; 151 152 /* 153 * IP6 output. The packet in mbuf chain m contains a skeletal IP6 154 * header (with pri, len, nxt, hlim, src, dst). 155 * This function may modify ver and hlim only. 156 * The mbuf chain containing the packet will be freed. 157 * The mbuf opt, if present, will not be freed. 158 * 159 * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int. 160 * We use u_long to hold largest one, * which is rt_mtu. 161 */ 162 int 163 ip6_output(struct mbuf *m, struct ip6_pktopts *opt, struct route_in6 *ro, 164 int flags, struct ip6_moptions *im6o, struct inpcb *inp) 165 { 166 struct ip6_hdr *ip6; 167 struct ifnet *ifp = NULL; 168 struct mbuf_list fml; 169 int hlen, tlen; 170 struct route_in6 ip6route; 171 struct rtentry *rt = NULL; 172 struct sockaddr_in6 *dst, dstsock; 173 int error = 0; 174 u_long mtu; 175 int dontfrag; 176 u_int16_t src_scope, dst_scope; 177 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; 178 struct ip6_exthdrs exthdrs; 179 struct in6_addr finaldst; 180 struct route_in6 *ro_pmtu = NULL; 181 int hdrsplit = 0; 182 u_int8_t sproto = 0; 183 u_char nextproto; 184 #ifdef IPSEC 185 struct tdb *tdb = NULL; 186 #endif /* IPSEC */ 187 188 #ifdef IPSEC 189 if (inp && (inp->inp_flags & INP_IPV6) == 0) 190 panic("%s: IPv4 pcb is passed", __func__); 191 #endif /* IPSEC */ 192 193 ip6 = mtod(m, struct ip6_hdr *); 194 finaldst = ip6->ip6_dst; 195 196 #define MAKE_EXTHDR(hp, mp) \ 197 do { \ 198 if (hp) { \ 199 struct ip6_ext *eh = (struct ip6_ext *)(hp); \ 200 error = ip6_copyexthdr((mp), (caddr_t)(hp), \ 201 ((eh)->ip6e_len + 1) << 3); \ 202 if (error) \ 203 goto freehdrs; \ 204 } \ 205 } while (0) 206 207 bzero(&exthdrs, sizeof(exthdrs)); 208 209 if (opt) { 210 /* Hop-by-Hop options header */ 211 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh); 212 /* Destination options header(1st part) */ 213 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1); 214 /* Routing header */ 215 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr); 216 /* Destination options header(2nd part) */ 217 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2); 218 } 219 220 #ifdef IPSEC 221 if (ipsec_in_use || inp != NULL) { 222 error = ip6_output_ipsec_lookup(m, inp, &tdb); 223 if (error) { 224 /* 225 * -EINVAL is used to indicate that the packet should 226 * be silently dropped, typically because we've asked 227 * key management for an SA. 228 */ 229 if (error == -EINVAL) /* Should silently drop packet */ 230 error = 0; 231 232 goto freehdrs; 233 } 234 } 235 #endif /* IPSEC */ 236 237 /* 238 * Calculate the total length of the extension header chain. 239 * Keep the length of the unfragmentable part for fragmentation. 240 */ 241 optlen = 0; 242 if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len; 243 if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len; 244 if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len; 245 unfragpartlen = optlen + sizeof(struct ip6_hdr); 246 /* NOTE: we don't add AH/ESP length here. do that later. */ 247 if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len; 248 249 /* 250 * If we need IPsec, or there is at least one extension header, 251 * separate IP6 header from the payload. 252 */ 253 if ((sproto || optlen) && !hdrsplit) { 254 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 255 m = NULL; 256 goto freehdrs; 257 } 258 m = exthdrs.ip6e_ip6; 259 hdrsplit++; 260 } 261 262 /* adjust pointer */ 263 ip6 = mtod(m, struct ip6_hdr *); 264 265 /* adjust mbuf packet header length */ 266 m->m_pkthdr.len += optlen; 267 plen = m->m_pkthdr.len - sizeof(*ip6); 268 269 /* If this is a jumbo payload, insert a jumbo payload option. */ 270 if (plen > IPV6_MAXPACKET) { 271 if (!hdrsplit) { 272 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 273 m = NULL; 274 goto freehdrs; 275 } 276 m = exthdrs.ip6e_ip6; 277 hdrsplit++; 278 } 279 /* adjust pointer */ 280 ip6 = mtod(m, struct ip6_hdr *); 281 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) 282 goto freehdrs; 283 ip6->ip6_plen = 0; 284 } else 285 ip6->ip6_plen = htons(plen); 286 287 /* 288 * Concatenate headers and fill in next header fields. 289 * Here we have, on "m" 290 * IPv6 payload 291 * and we insert headers accordingly. Finally, we should be getting: 292 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 293 * 294 * during the header composing process, "m" points to IPv6 header. 295 * "mprev" points to an extension header prior to esp. 296 */ 297 { 298 u_char *nexthdrp = &ip6->ip6_nxt; 299 struct mbuf *mprev = m; 300 301 /* 302 * we treat dest2 specially. this makes IPsec processing 303 * much easier. the goal here is to make mprev point the 304 * mbuf prior to dest2. 305 * 306 * result: IPv6 dest2 payload 307 * m and mprev will point to IPv6 header. 308 */ 309 if (exthdrs.ip6e_dest2) { 310 if (!hdrsplit) 311 panic("%s: assumption failed: hdr not split", 312 __func__); 313 exthdrs.ip6e_dest2->m_next = m->m_next; 314 m->m_next = exthdrs.ip6e_dest2; 315 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; 316 ip6->ip6_nxt = IPPROTO_DSTOPTS; 317 } 318 319 #define MAKE_CHAIN(m, mp, p, i)\ 320 do {\ 321 if (m) {\ 322 if (!hdrsplit) \ 323 panic("assumption failed: hdr not split"); \ 324 *mtod((m), u_char *) = *(p);\ 325 *(p) = (i);\ 326 p = mtod((m), u_char *);\ 327 (m)->m_next = (mp)->m_next;\ 328 (mp)->m_next = (m);\ 329 (mp) = (m);\ 330 }\ 331 } while (0) 332 /* 333 * result: IPv6 hbh dest1 rthdr dest2 payload 334 * m will point to IPv6 header. mprev will point to the 335 * extension header prior to dest2 (rthdr in the above case). 336 */ 337 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); 338 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, 339 IPPROTO_DSTOPTS); 340 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, 341 IPPROTO_ROUTING); 342 } 343 344 /* 345 * If there is a routing header, replace the destination address field 346 * with the first hop of the routing header. 347 */ 348 if (exthdrs.ip6e_rthdr) { 349 struct ip6_rthdr *rh; 350 struct ip6_rthdr0 *rh0; 351 struct in6_addr *addr; 352 353 rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr, 354 struct ip6_rthdr *)); 355 switch (rh->ip6r_type) { 356 case IPV6_RTHDR_TYPE_0: 357 rh0 = (struct ip6_rthdr0 *)rh; 358 addr = (struct in6_addr *)(rh0 + 1); 359 ip6->ip6_dst = addr[0]; 360 bcopy(&addr[1], &addr[0], 361 sizeof(struct in6_addr) * (rh0->ip6r0_segleft - 1)); 362 addr[rh0->ip6r0_segleft - 1] = finaldst; 363 break; 364 default: /* is it possible? */ 365 error = EINVAL; 366 goto bad; 367 } 368 } 369 370 /* Source address validation */ 371 if (!(flags & IPV6_UNSPECSRC) && 372 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) { 373 /* 374 * XXX: we can probably assume validation in the caller, but 375 * we explicitly check the address here for safety. 376 */ 377 error = EOPNOTSUPP; 378 ip6stat_inc(ip6s_badscope); 379 goto bad; 380 } 381 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { 382 error = EOPNOTSUPP; 383 ip6stat_inc(ip6s_badscope); 384 goto bad; 385 } 386 387 ip6stat_inc(ip6s_localout); 388 389 /* 390 * Route packet. 391 */ 392 #if NPF > 0 393 reroute: 394 #endif 395 396 /* initialize cached route */ 397 if (ro == NULL) { 398 ro = &ip6route; 399 bzero((caddr_t)ro, sizeof(*ro)); 400 } 401 ro_pmtu = ro; 402 if (opt && opt->ip6po_rthdr) 403 ro = &opt->ip6po_route; 404 dst = &ro->ro_dst; 405 406 /* 407 * if specified, try to fill in the traffic class field. 408 * do not override if a non-zero value is already set. 409 * we check the diffserv field and the ecn field separately. 410 */ 411 if (opt && opt->ip6po_tclass >= 0) { 412 int mask = 0; 413 414 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0) 415 mask |= 0xfc; 416 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0) 417 mask |= 0x03; 418 if (mask != 0) 419 ip6->ip6_flow |= 420 htonl((opt->ip6po_tclass & mask) << 20); 421 } 422 423 /* fill in or override the hop limit field, if necessary. */ 424 if (opt && opt->ip6po_hlim != -1) 425 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 426 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 427 if (im6o != NULL) 428 ip6->ip6_hlim = im6o->im6o_hlim; 429 else 430 ip6->ip6_hlim = ip6_defmcasthlim; 431 } 432 433 #ifdef IPSEC 434 if (tdb != NULL) { 435 /* 436 * XXX what should we do if ip6_hlim == 0 and the 437 * packet gets tunneled? 438 */ 439 /* 440 * if we are source-routing, do not attempt to tunnel the 441 * packet just because ip6_dst is different from what tdb has. 442 * XXX 443 */ 444 error = ip6_output_ipsec_send(tdb, m, ro, 445 exthdrs.ip6e_rthdr ? 1 : 0, 0); 446 goto done; 447 } 448 #endif /* IPSEC */ 449 450 bzero(&dstsock, sizeof(dstsock)); 451 dstsock.sin6_family = AF_INET6; 452 dstsock.sin6_addr = ip6->ip6_dst; 453 dstsock.sin6_len = sizeof(dstsock); 454 ro->ro_tableid = m->m_pkthdr.ph_rtableid; 455 456 if (IN6_IS_ADDR_MULTICAST(&dstsock.sin6_addr)) { 457 struct in6_pktinfo *pi = NULL; 458 459 /* 460 * If the caller specify the outgoing interface 461 * explicitly, use it. 462 */ 463 if (opt != NULL && (pi = opt->ip6po_pktinfo) != NULL) 464 ifp = if_get(pi->ipi6_ifindex); 465 466 if (ifp == NULL && im6o != NULL) 467 ifp = if_get(im6o->im6o_ifidx); 468 } 469 470 if (ifp == NULL) { 471 rt = in6_selectroute(&dstsock, opt, ro, ro->ro_tableid); 472 if (rt == NULL) { 473 ip6stat_inc(ip6s_noroute); 474 error = EHOSTUNREACH; 475 goto bad; 476 } 477 if (ISSET(rt->rt_flags, RTF_LOCAL)) 478 ifp = if_get(rtable_loindex(m->m_pkthdr.ph_rtableid)); 479 else 480 ifp = if_get(rt->rt_ifidx); 481 /* 482 * We aren't using rtisvalid() here because the UP/DOWN state 483 * machine is broken with some Ethernet drivers like em(4). 484 * As a result we might try to use an invalid cached route 485 * entry while an interface is being detached. 486 */ 487 if (ifp == NULL) { 488 ip6stat_inc(ip6s_noroute); 489 error = EHOSTUNREACH; 490 goto bad; 491 } 492 } else { 493 *dst = dstsock; 494 } 495 496 if (rt && (rt->rt_flags & RTF_GATEWAY) && 497 !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 498 dst = satosin6(rt->rt_gateway); 499 500 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 501 /* Unicast */ 502 503 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ 504 } else { 505 /* Multicast */ 506 507 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; 508 509 /* 510 * Confirm that the outgoing interface supports multicast. 511 */ 512 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 513 ip6stat_inc(ip6s_noroute); 514 error = ENETUNREACH; 515 goto bad; 516 } 517 518 if ((im6o == NULL || im6o->im6o_loop) && 519 in6_hasmulti(&ip6->ip6_dst, ifp)) { 520 /* 521 * If we belong to the destination multicast group 522 * on the outgoing interface, and the caller did not 523 * forbid loopback, loop back a copy. 524 * Can't defer TCP/UDP checksumming, do the 525 * computation now. 526 */ 527 in6_proto_cksum_out(m, NULL); 528 ip6_mloopback(ifp, m, dst); 529 } 530 #ifdef MROUTING 531 else { 532 /* 533 * If we are acting as a multicast router, perform 534 * multicast forwarding as if the packet had just 535 * arrived on the interface to which we are about 536 * to send. The multicast forwarding function 537 * recursively calls this function, using the 538 * IPV6_FORWARDING flag to prevent infinite recursion. 539 * 540 * Multicasts that are looped back by ip6_mloopback(), 541 * above, will be forwarded by the ip6_input() routine, 542 * if necessary. 543 */ 544 if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain] && 545 (flags & IPV6_FORWARDING) == 0) { 546 if (ip6_mforward(ip6, ifp, m) != 0) { 547 m_freem(m); 548 goto done; 549 } 550 } 551 } 552 #endif 553 /* 554 * Multicasts with a hoplimit of zero may be looped back, 555 * above, but must not be transmitted on a network. 556 * Also, multicasts addressed to the loopback interface 557 * are not sent -- the above call to ip6_mloopback() will 558 * loop back a copy if this host actually belongs to the 559 * destination group on the loopback interface. 560 */ 561 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) || 562 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) { 563 m_freem(m); 564 goto done; 565 } 566 } 567 568 /* 569 * If this packet is going through a loopback interface we won't 570 * be able to restore its scope ID using the interface index. 571 */ 572 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { 573 if (ifp->if_flags & IFF_LOOPBACK) 574 src_scope = ip6->ip6_src.s6_addr16[1]; 575 ip6->ip6_src.s6_addr16[1] = 0; 576 } 577 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { 578 if (ifp->if_flags & IFF_LOOPBACK) 579 dst_scope = ip6->ip6_dst.s6_addr16[1]; 580 ip6->ip6_dst.s6_addr16[1] = 0; 581 } 582 583 /* Determine path MTU. */ 584 if ((error = ip6_getpmtu(ro_pmtu->ro_rt, ifp, &mtu)) != 0) 585 goto bad; 586 587 /* 588 * The caller of this function may specify to use the minimum MTU 589 * in some cases. 590 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU 591 * setting. The logic is a bit complicated; by default, unicast 592 * packets will follow path MTU while multicast packets will be sent at 593 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets 594 * including unicast ones will be sent at the minimum MTU. Multicast 595 * packets will always be sent at the minimum MTU unless 596 * IP6PO_MINMTU_DISABLE is explicitly specified. 597 * See RFC 3542 for more details. 598 */ 599 if (mtu > IPV6_MMTU) { 600 if ((flags & IPV6_MINMTU)) 601 mtu = IPV6_MMTU; 602 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL) 603 mtu = IPV6_MMTU; 604 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && (opt == NULL || 605 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) { 606 mtu = IPV6_MMTU; 607 } 608 } 609 610 /* 611 * If the outgoing packet contains a hop-by-hop options header, 612 * it must be examined and processed even by the source node. 613 * (RFC 2460, section 4.) 614 */ 615 if (exthdrs.ip6e_hbh) { 616 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *); 617 u_int32_t rtalert; /* returned value is ignored */ 618 u_int32_t plen = 0; /* no more than 1 jumbo payload option! */ 619 620 m->m_pkthdr.ph_ifidx = ifp->if_index; 621 if (ip6_process_hopopts(&m, (u_int8_t *)(hbh + 1), 622 ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh), 623 &rtalert, &plen) < 0) { 624 /* m was already freed at this point */ 625 error = EINVAL;/* better error? */ 626 goto done; 627 } 628 m->m_pkthdr.ph_ifidx = 0; 629 } 630 631 #if NPF > 0 632 if (pf_test(AF_INET6, PF_OUT, ifp, &m) != PF_PASS) { 633 error = EACCES; 634 m_freem(m); 635 goto done; 636 } 637 if (m == NULL) 638 goto done; 639 ip6 = mtod(m, struct ip6_hdr *); 640 if ((m->m_pkthdr.pf.flags & (PF_TAG_REROUTE | PF_TAG_GENERATED)) == 641 (PF_TAG_REROUTE | PF_TAG_GENERATED)) { 642 /* already rerun the route lookup, go on */ 643 m->m_pkthdr.pf.flags &= ~(PF_TAG_GENERATED | PF_TAG_REROUTE); 644 } else if (m->m_pkthdr.pf.flags & PF_TAG_REROUTE) { 645 /* tag as generated to skip over pf_test on rerun */ 646 m->m_pkthdr.pf.flags |= PF_TAG_GENERATED; 647 finaldst = ip6->ip6_dst; 648 ro = NULL; 649 if_put(ifp); /* drop reference since destination changed */ 650 ifp = NULL; 651 goto reroute; 652 } 653 #endif 654 655 /* 656 * If the packet is not going on the wire it can be destined 657 * to any local address. In this case do not clear its scopes 658 * to let ip6_input() find a matching local route. 659 */ 660 if (ifp->if_flags & IFF_LOOPBACK) { 661 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 662 ip6->ip6_src.s6_addr16[1] = src_scope; 663 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 664 ip6->ip6_dst.s6_addr16[1] = dst_scope; 665 } 666 667 in6_proto_cksum_out(m, ifp); 668 669 /* 670 * Send the packet to the outgoing interface. 671 * If necessary, do IPv6 fragmentation before sending. 672 * 673 * the logic here is rather complex: 674 * 1: normal case (dontfrag == 0) 675 * 1-a: send as is if tlen <= path mtu 676 * 1-b: fragment if tlen > path mtu 677 * 678 * 2: if user asks us not to fragment (dontfrag == 1) 679 * 2-a: send as is if tlen <= interface mtu 680 * 2-b: error if tlen > interface mtu 681 */ 682 tlen = m->m_pkthdr.len; 683 684 if (ISSET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT)) { 685 CLR(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT); 686 dontfrag = 1; 687 } else if (opt && ISSET(opt->ip6po_flags, IP6PO_DONTFRAG)) 688 dontfrag = 1; 689 else 690 dontfrag = 0; 691 if (dontfrag && tlen > ifp->if_mtu) { /* case 2-b */ 692 #ifdef IPSEC 693 if (ip_mtudisc) 694 ipsec_adjust_mtu(m, mtu); 695 #endif 696 error = EMSGSIZE; 697 goto bad; 698 } 699 700 /* 701 * transmit packet without fragmentation 702 */ 703 if (dontfrag || (tlen <= mtu)) { /* case 1-a and 2-a */ 704 error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt); 705 goto done; 706 } 707 708 /* 709 * try to fragment the packet. case 1-b 710 */ 711 if (mtu < IPV6_MMTU) { 712 /* path MTU cannot be less than IPV6_MMTU */ 713 error = EMSGSIZE; 714 goto bad; 715 } else if (ip6->ip6_plen == 0) { 716 /* jumbo payload cannot be fragmented */ 717 error = EMSGSIZE; 718 goto bad; 719 } 720 721 /* 722 * Too large for the destination or interface; 723 * fragment if possible. 724 * Must be able to put at least 8 bytes per fragment. 725 */ 726 hlen = unfragpartlen; 727 if (mtu > IPV6_MAXPACKET) 728 mtu = IPV6_MAXPACKET; 729 730 /* 731 * If we are doing fragmentation, we can't defer TCP/UDP 732 * checksumming; compute the checksum and clear the flag. 733 */ 734 in6_proto_cksum_out(m, NULL); 735 736 /* 737 * Change the next header field of the last header in the 738 * unfragmentable part. 739 */ 740 if (exthdrs.ip6e_rthdr) { 741 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); 742 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; 743 } else if (exthdrs.ip6e_dest1) { 744 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); 745 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; 746 } else if (exthdrs.ip6e_hbh) { 747 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); 748 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; 749 } else { 750 nextproto = ip6->ip6_nxt; 751 ip6->ip6_nxt = IPPROTO_FRAGMENT; 752 } 753 754 error = ip6_fragment(m, &fml, hlen, nextproto, mtu); 755 if (error) 756 goto done; 757 758 while ((m = ml_dequeue(&fml)) != NULL) { 759 error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt); 760 if (error) 761 break; 762 } 763 if (error) 764 ml_purge(&fml); 765 else 766 ip6stat_inc(ip6s_fragmented); 767 768 done: 769 if (ro == &ip6route && ro->ro_rt) { 770 rtfree(ro->ro_rt); 771 } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) { 772 rtfree(ro_pmtu->ro_rt); 773 } 774 if_put(ifp); 775 #ifdef IPSEC 776 tdb_unref(tdb); 777 #endif /* IPSEC */ 778 return (error); 779 780 freehdrs: 781 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */ 782 m_freem(exthdrs.ip6e_dest1); 783 m_freem(exthdrs.ip6e_rthdr); 784 m_freem(exthdrs.ip6e_dest2); 785 /* FALLTHROUGH */ 786 bad: 787 m_freem(m); 788 goto done; 789 } 790 791 int 792 ip6_fragment(struct mbuf *m0, struct mbuf_list *fml, int hlen, 793 u_char nextproto, u_long mtu) 794 { 795 struct mbuf *m; 796 struct ip6_hdr *ip6; 797 u_int32_t id; 798 int tlen, len, off; 799 int error; 800 801 ml_init(fml); 802 803 ip6 = mtod(m0, struct ip6_hdr *); 804 tlen = m0->m_pkthdr.len; 805 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; 806 if (len < 8) { 807 error = EMSGSIZE; 808 goto bad; 809 } 810 id = htonl(ip6_randomid()); 811 812 /* 813 * Loop through length of segment, 814 * make new header and copy data of each part and link onto chain. 815 */ 816 for (off = hlen; off < tlen; off += len) { 817 struct mbuf *mlast; 818 struct ip6_hdr *mhip6; 819 struct ip6_frag *ip6f; 820 821 MGETHDR(m, M_DONTWAIT, MT_HEADER); 822 if (m == NULL) { 823 error = ENOBUFS; 824 goto bad; 825 } 826 ml_enqueue(fml, m); 827 828 if ((error = m_dup_pkthdr(m, m0, M_DONTWAIT)) != 0) 829 goto bad; 830 m->m_data += max_linkhdr; 831 mhip6 = mtod(m, struct ip6_hdr *); 832 *mhip6 = *ip6; 833 m->m_len = sizeof(struct ip6_hdr); 834 835 if ((error = ip6_insertfraghdr(m0, m, hlen, &ip6f)) != 0) 836 goto bad; 837 ip6f->ip6f_offlg = htons((off - hlen) & ~7); 838 if (off + len >= tlen) 839 len = tlen - off; 840 else 841 ip6f->ip6f_offlg |= IP6F_MORE_FRAG; 842 843 m->m_pkthdr.len = hlen + sizeof(struct ip6_frag) + len; 844 mhip6->ip6_plen = htons(m->m_pkthdr.len - 845 sizeof(struct ip6_hdr)); 846 for (mlast = m; mlast->m_next; mlast = mlast->m_next) 847 ; 848 mlast->m_next = m_copym(m0, off, len, M_DONTWAIT); 849 if (mlast->m_next == NULL) { 850 error = ENOBUFS; 851 goto bad; 852 } 853 854 ip6f->ip6f_reserved = 0; 855 ip6f->ip6f_ident = id; 856 ip6f->ip6f_nxt = nextproto; 857 } 858 859 ip6stat_add(ip6s_ofragments, ml_len(fml)); 860 m_freem(m0); 861 return (0); 862 863 bad: 864 ip6stat_inc(ip6s_odropped); 865 ml_purge(fml); 866 m_freem(m0); 867 return (error); 868 } 869 870 int 871 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen) 872 { 873 struct mbuf *m; 874 875 if (hlen > MCLBYTES) 876 return (ENOBUFS); /* XXX */ 877 878 MGET(m, M_DONTWAIT, MT_DATA); 879 if (!m) 880 return (ENOBUFS); 881 882 if (hlen > MLEN) { 883 MCLGET(m, M_DONTWAIT); 884 if ((m->m_flags & M_EXT) == 0) { 885 m_free(m); 886 return (ENOBUFS); 887 } 888 } 889 m->m_len = hlen; 890 if (hdr) 891 memcpy(mtod(m, caddr_t), hdr, hlen); 892 893 *mp = m; 894 return (0); 895 } 896 897 /* 898 * Insert jumbo payload option. 899 */ 900 int 901 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen) 902 { 903 struct mbuf *mopt; 904 u_int8_t *optbuf; 905 u_int32_t v; 906 907 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */ 908 909 /* 910 * If there is no hop-by-hop options header, allocate new one. 911 * If there is one but it doesn't have enough space to store the 912 * jumbo payload option, allocate a cluster to store the whole options. 913 * Otherwise, use it to store the options. 914 */ 915 if (exthdrs->ip6e_hbh == 0) { 916 MGET(mopt, M_DONTWAIT, MT_DATA); 917 if (mopt == NULL) 918 return (ENOBUFS); 919 mopt->m_len = JUMBOOPTLEN; 920 optbuf = mtod(mopt, u_int8_t *); 921 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */ 922 exthdrs->ip6e_hbh = mopt; 923 } else { 924 struct ip6_hbh *hbh; 925 926 mopt = exthdrs->ip6e_hbh; 927 if (m_trailingspace(mopt) < JUMBOOPTLEN) { 928 /* 929 * XXX assumption: 930 * - exthdrs->ip6e_hbh is not referenced from places 931 * other than exthdrs. 932 * - exthdrs->ip6e_hbh is not an mbuf chain. 933 */ 934 int oldoptlen = mopt->m_len; 935 struct mbuf *n; 936 937 /* 938 * XXX: give up if the whole (new) hbh header does 939 * not fit even in an mbuf cluster. 940 */ 941 if (oldoptlen + JUMBOOPTLEN > MCLBYTES) 942 return (ENOBUFS); 943 944 /* 945 * As a consequence, we must always prepare a cluster 946 * at this point. 947 */ 948 MGET(n, M_DONTWAIT, MT_DATA); 949 if (n) { 950 MCLGET(n, M_DONTWAIT); 951 if ((n->m_flags & M_EXT) == 0) { 952 m_freem(n); 953 n = NULL; 954 } 955 } 956 if (!n) 957 return (ENOBUFS); 958 n->m_len = oldoptlen + JUMBOOPTLEN; 959 memcpy(mtod(n, caddr_t), mtod(mopt, caddr_t), 960 oldoptlen); 961 optbuf = mtod(n, u_int8_t *) + oldoptlen; 962 m_freem(mopt); 963 mopt = exthdrs->ip6e_hbh = n; 964 } else { 965 optbuf = mtod(mopt, u_int8_t *) + mopt->m_len; 966 mopt->m_len += JUMBOOPTLEN; 967 } 968 optbuf[0] = IP6OPT_PADN; 969 optbuf[1] = 0; 970 971 /* 972 * Adjust the header length according to the pad and 973 * the jumbo payload option. 974 */ 975 hbh = mtod(mopt, struct ip6_hbh *); 976 hbh->ip6h_len += (JUMBOOPTLEN >> 3); 977 } 978 979 /* fill in the option. */ 980 optbuf[2] = IP6OPT_JUMBO; 981 optbuf[3] = 4; 982 v = (u_int32_t)htonl(plen + JUMBOOPTLEN); 983 memcpy(&optbuf[4], &v, sizeof(u_int32_t)); 984 985 /* finally, adjust the packet header length */ 986 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN; 987 988 return (0); 989 #undef JUMBOOPTLEN 990 } 991 992 /* 993 * Insert fragment header and copy unfragmentable header portions. 994 */ 995 int 996 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen, 997 struct ip6_frag **frghdrp) 998 { 999 struct mbuf *n, *mlast; 1000 1001 if (hlen > sizeof(struct ip6_hdr)) { 1002 n = m_copym(m0, sizeof(struct ip6_hdr), 1003 hlen - sizeof(struct ip6_hdr), M_DONTWAIT); 1004 if (n == NULL) 1005 return (ENOBUFS); 1006 m->m_next = n; 1007 } else 1008 n = m; 1009 1010 /* Search for the last mbuf of unfragmentable part. */ 1011 for (mlast = n; mlast->m_next; mlast = mlast->m_next) 1012 ; 1013 1014 if ((mlast->m_flags & M_EXT) == 0 && 1015 m_trailingspace(mlast) >= sizeof(struct ip6_frag)) { 1016 /* use the trailing space of the last mbuf for fragment hdr */ 1017 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) + 1018 mlast->m_len); 1019 mlast->m_len += sizeof(struct ip6_frag); 1020 m->m_pkthdr.len += sizeof(struct ip6_frag); 1021 } else { 1022 /* allocate a new mbuf for the fragment header */ 1023 struct mbuf *mfrg; 1024 1025 MGET(mfrg, M_DONTWAIT, MT_DATA); 1026 if (mfrg == NULL) 1027 return (ENOBUFS); 1028 mfrg->m_len = sizeof(struct ip6_frag); 1029 *frghdrp = mtod(mfrg, struct ip6_frag *); 1030 mlast->m_next = mfrg; 1031 } 1032 1033 return (0); 1034 } 1035 1036 int 1037 ip6_getpmtu(struct rtentry *rt, struct ifnet *ifp, u_long *mtup) 1038 { 1039 u_int32_t mtu = 0; 1040 int error = 0; 1041 1042 if (rt != NULL) { 1043 mtu = rt->rt_mtu; 1044 if (mtu == 0) 1045 mtu = ifp->if_mtu; 1046 else if (mtu < IPV6_MMTU) { 1047 /* RFC8021 IPv6 Atomic Fragments Considered Harmful */ 1048 mtu = IPV6_MMTU; 1049 } else if (mtu > ifp->if_mtu) { 1050 /* 1051 * The MTU on the route is larger than the MTU on 1052 * the interface! This shouldn't happen, unless the 1053 * MTU of the interface has been changed after the 1054 * interface was brought up. Change the MTU in the 1055 * route to match the interface MTU (as long as the 1056 * field isn't locked). 1057 */ 1058 mtu = ifp->if_mtu; 1059 if (!(rt->rt_locks & RTV_MTU)) 1060 rt->rt_mtu = mtu; 1061 } 1062 } else { 1063 mtu = ifp->if_mtu; 1064 } 1065 1066 *mtup = mtu; 1067 return (error); 1068 } 1069 1070 /* 1071 * IP6 socket option processing. 1072 */ 1073 int 1074 ip6_ctloutput(int op, struct socket *so, int level, int optname, 1075 struct mbuf *m) 1076 { 1077 int privileged, optdatalen, uproto; 1078 void *optdata; 1079 struct inpcb *inp = sotoinpcb(so); 1080 int error, optval; 1081 struct proc *p = curproc; /* For IPsec and rdomain */ 1082 u_int rtableid, rtid = 0; 1083 1084 error = optval = 0; 1085 1086 privileged = (inp->inp_socket->so_state & SS_PRIV); 1087 uproto = (int)so->so_proto->pr_protocol; 1088 1089 if (level != IPPROTO_IPV6) 1090 return (EINVAL); 1091 1092 rtableid = p->p_p->ps_rtableid; 1093 1094 switch (op) { 1095 case PRCO_SETOPT: 1096 switch (optname) { 1097 /* 1098 * Use of some Hop-by-Hop options or some 1099 * Destination options, might require special 1100 * privilege. That is, normal applications 1101 * (without special privilege) might be forbidden 1102 * from setting certain options in outgoing packets, 1103 * and might never see certain options in received 1104 * packets. [RFC 2292 Section 6] 1105 * KAME specific note: 1106 * KAME prevents non-privileged users from sending or 1107 * receiving ANY hbh/dst options in order to avoid 1108 * overhead of parsing options in the kernel. 1109 */ 1110 case IPV6_RECVHOPOPTS: 1111 case IPV6_RECVDSTOPTS: 1112 if (!privileged) { 1113 error = EPERM; 1114 break; 1115 } 1116 /* FALLTHROUGH */ 1117 case IPV6_UNICAST_HOPS: 1118 case IPV6_MINHOPCOUNT: 1119 case IPV6_HOPLIMIT: 1120 1121 case IPV6_RECVPKTINFO: 1122 case IPV6_RECVHOPLIMIT: 1123 case IPV6_RECVRTHDR: 1124 case IPV6_RECVPATHMTU: 1125 case IPV6_RECVTCLASS: 1126 case IPV6_V6ONLY: 1127 case IPV6_AUTOFLOWLABEL: 1128 case IPV6_RECVDSTPORT: 1129 if (m == NULL || m->m_len != sizeof(int)) { 1130 error = EINVAL; 1131 break; 1132 } 1133 optval = *mtod(m, int *); 1134 switch (optname) { 1135 1136 case IPV6_UNICAST_HOPS: 1137 if (optval < -1 || optval >= 256) 1138 error = EINVAL; 1139 else { 1140 /* -1 = kernel default */ 1141 inp->inp_hops = optval; 1142 } 1143 break; 1144 1145 case IPV6_MINHOPCOUNT: 1146 if (optval < 0 || optval > 255) 1147 error = EINVAL; 1148 else 1149 inp->inp_ip6_minhlim = optval; 1150 break; 1151 1152 #define OPTSET(bit) \ 1153 do { \ 1154 if (optval) \ 1155 inp->inp_flags |= (bit); \ 1156 else \ 1157 inp->inp_flags &= ~(bit); \ 1158 } while (/*CONSTCOND*/ 0) 1159 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0) 1160 1161 case IPV6_RECVPKTINFO: 1162 OPTSET(IN6P_PKTINFO); 1163 break; 1164 1165 case IPV6_HOPLIMIT: 1166 { 1167 struct ip6_pktopts **optp; 1168 1169 optp = &inp->inp_outputopts6; 1170 error = ip6_pcbopt(IPV6_HOPLIMIT, 1171 (u_char *)&optval, sizeof(optval), optp, 1172 privileged, uproto); 1173 break; 1174 } 1175 1176 case IPV6_RECVHOPLIMIT: 1177 OPTSET(IN6P_HOPLIMIT); 1178 break; 1179 1180 case IPV6_RECVHOPOPTS: 1181 OPTSET(IN6P_HOPOPTS); 1182 break; 1183 1184 case IPV6_RECVDSTOPTS: 1185 OPTSET(IN6P_DSTOPTS); 1186 break; 1187 1188 case IPV6_RECVRTHDR: 1189 OPTSET(IN6P_RTHDR); 1190 break; 1191 1192 case IPV6_RECVPATHMTU: 1193 /* 1194 * We ignore this option for TCP 1195 * sockets. 1196 * (RFC3542 leaves this case 1197 * unspecified.) 1198 */ 1199 if (uproto != IPPROTO_TCP) 1200 OPTSET(IN6P_MTU); 1201 break; 1202 1203 case IPV6_V6ONLY: 1204 /* 1205 * make setsockopt(IPV6_V6ONLY) 1206 * available only prior to bind(2). 1207 * see ipng mailing list, Jun 22 2001. 1208 */ 1209 if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED( 1210 &inp->inp_laddr6)) { 1211 error = EINVAL; 1212 break; 1213 } 1214 /* No support for IPv4-mapped addresses. */ 1215 if (!optval) 1216 error = EINVAL; 1217 else 1218 error = 0; 1219 break; 1220 case IPV6_RECVTCLASS: 1221 OPTSET(IN6P_TCLASS); 1222 break; 1223 case IPV6_AUTOFLOWLABEL: 1224 OPTSET(IN6P_AUTOFLOWLABEL); 1225 break; 1226 1227 case IPV6_RECVDSTPORT: 1228 OPTSET(IN6P_RECVDSTPORT); 1229 break; 1230 } 1231 break; 1232 1233 case IPV6_TCLASS: 1234 case IPV6_DONTFRAG: 1235 case IPV6_USE_MIN_MTU: 1236 if (m == NULL || m->m_len != sizeof(optval)) { 1237 error = EINVAL; 1238 break; 1239 } 1240 optval = *mtod(m, int *); 1241 { 1242 struct ip6_pktopts **optp; 1243 optp = &inp->inp_outputopts6; 1244 error = ip6_pcbopt(optname, (u_char *)&optval, 1245 sizeof(optval), optp, privileged, uproto); 1246 break; 1247 } 1248 1249 case IPV6_PKTINFO: 1250 case IPV6_HOPOPTS: 1251 case IPV6_RTHDR: 1252 case IPV6_DSTOPTS: 1253 case IPV6_RTHDRDSTOPTS: 1254 { 1255 /* new advanced API (RFC3542) */ 1256 u_char *optbuf; 1257 int optbuflen; 1258 struct ip6_pktopts **optp; 1259 1260 if (m && m->m_next) { 1261 error = EINVAL; /* XXX */ 1262 break; 1263 } 1264 if (m) { 1265 optbuf = mtod(m, u_char *); 1266 optbuflen = m->m_len; 1267 } else { 1268 optbuf = NULL; 1269 optbuflen = 0; 1270 } 1271 optp = &inp->inp_outputopts6; 1272 error = ip6_pcbopt(optname, optbuf, optbuflen, optp, 1273 privileged, uproto); 1274 break; 1275 } 1276 #undef OPTSET 1277 1278 case IPV6_MULTICAST_IF: 1279 case IPV6_MULTICAST_HOPS: 1280 case IPV6_MULTICAST_LOOP: 1281 case IPV6_JOIN_GROUP: 1282 case IPV6_LEAVE_GROUP: 1283 error = ip6_setmoptions(optname, 1284 &inp->inp_moptions6, 1285 m, inp->inp_rtableid); 1286 break; 1287 1288 case IPV6_PORTRANGE: 1289 if (m == NULL || m->m_len != sizeof(int)) { 1290 error = EINVAL; 1291 break; 1292 } 1293 optval = *mtod(m, int *); 1294 1295 switch (optval) { 1296 case IPV6_PORTRANGE_DEFAULT: 1297 inp->inp_flags &= ~(IN6P_LOWPORT); 1298 inp->inp_flags &= ~(IN6P_HIGHPORT); 1299 break; 1300 1301 case IPV6_PORTRANGE_HIGH: 1302 inp->inp_flags &= ~(IN6P_LOWPORT); 1303 inp->inp_flags |= IN6P_HIGHPORT; 1304 break; 1305 1306 case IPV6_PORTRANGE_LOW: 1307 inp->inp_flags &= ~(IN6P_HIGHPORT); 1308 inp->inp_flags |= IN6P_LOWPORT; 1309 break; 1310 1311 default: 1312 error = EINVAL; 1313 break; 1314 } 1315 break; 1316 1317 case IPSEC6_OUTSA: 1318 error = EINVAL; 1319 break; 1320 1321 case IPV6_AUTH_LEVEL: 1322 case IPV6_ESP_TRANS_LEVEL: 1323 case IPV6_ESP_NETWORK_LEVEL: 1324 case IPV6_IPCOMP_LEVEL: 1325 #ifndef IPSEC 1326 error = EINVAL; 1327 #else 1328 if (m == NULL || m->m_len != sizeof(int)) { 1329 error = EINVAL; 1330 break; 1331 } 1332 optval = *mtod(m, int *); 1333 1334 if (optval < IPSEC_LEVEL_BYPASS || 1335 optval > IPSEC_LEVEL_UNIQUE) { 1336 error = EINVAL; 1337 break; 1338 } 1339 1340 switch (optname) { 1341 case IPV6_AUTH_LEVEL: 1342 if (optval < IPSEC_AUTH_LEVEL_DEFAULT && 1343 suser(p)) { 1344 error = EACCES; 1345 break; 1346 } 1347 inp->inp_seclevel[SL_AUTH] = optval; 1348 break; 1349 1350 case IPV6_ESP_TRANS_LEVEL: 1351 if (optval < IPSEC_ESP_TRANS_LEVEL_DEFAULT && 1352 suser(p)) { 1353 error = EACCES; 1354 break; 1355 } 1356 inp->inp_seclevel[SL_ESP_TRANS] = optval; 1357 break; 1358 1359 case IPV6_ESP_NETWORK_LEVEL: 1360 if (optval < IPSEC_ESP_NETWORK_LEVEL_DEFAULT && 1361 suser(p)) { 1362 error = EACCES; 1363 break; 1364 } 1365 inp->inp_seclevel[SL_ESP_NETWORK] = optval; 1366 break; 1367 1368 case IPV6_IPCOMP_LEVEL: 1369 if (optval < IPSEC_IPCOMP_LEVEL_DEFAULT && 1370 suser(p)) { 1371 error = EACCES; 1372 break; 1373 } 1374 inp->inp_seclevel[SL_IPCOMP] = optval; 1375 break; 1376 } 1377 #endif 1378 break; 1379 case SO_RTABLE: 1380 if (m == NULL || m->m_len < sizeof(u_int)) { 1381 error = EINVAL; 1382 break; 1383 } 1384 rtid = *mtod(m, u_int *); 1385 if (inp->inp_rtableid == rtid) 1386 break; 1387 /* needs privileges to switch when already set */ 1388 if (rtableid != rtid && rtableid != 0 && 1389 (error = suser(p)) != 0) 1390 break; 1391 /* table must exist */ 1392 if (!rtable_exists(rtid)) { 1393 error = EINVAL; 1394 break; 1395 } 1396 if (inp->inp_lport) { 1397 error = EBUSY; 1398 break; 1399 } 1400 inp->inp_rtableid = rtid; 1401 in_pcbrehash(inp); 1402 break; 1403 case IPV6_PIPEX: 1404 if (m != NULL && m->m_len == sizeof(int)) 1405 inp->inp_pipex = *mtod(m, int *); 1406 else 1407 error = EINVAL; 1408 break; 1409 1410 default: 1411 error = ENOPROTOOPT; 1412 break; 1413 } 1414 break; 1415 1416 case PRCO_GETOPT: 1417 switch (optname) { 1418 1419 case IPV6_RECVHOPOPTS: 1420 case IPV6_RECVDSTOPTS: 1421 case IPV6_UNICAST_HOPS: 1422 case IPV6_MINHOPCOUNT: 1423 case IPV6_RECVPKTINFO: 1424 case IPV6_RECVHOPLIMIT: 1425 case IPV6_RECVRTHDR: 1426 case IPV6_RECVPATHMTU: 1427 1428 case IPV6_V6ONLY: 1429 case IPV6_PORTRANGE: 1430 case IPV6_RECVTCLASS: 1431 case IPV6_AUTOFLOWLABEL: 1432 case IPV6_RECVDSTPORT: 1433 switch (optname) { 1434 1435 case IPV6_RECVHOPOPTS: 1436 optval = OPTBIT(IN6P_HOPOPTS); 1437 break; 1438 1439 case IPV6_RECVDSTOPTS: 1440 optval = OPTBIT(IN6P_DSTOPTS); 1441 break; 1442 1443 case IPV6_UNICAST_HOPS: 1444 optval = inp->inp_hops; 1445 break; 1446 1447 case IPV6_MINHOPCOUNT: 1448 optval = inp->inp_ip6_minhlim; 1449 break; 1450 1451 case IPV6_RECVPKTINFO: 1452 optval = OPTBIT(IN6P_PKTINFO); 1453 break; 1454 1455 case IPV6_RECVHOPLIMIT: 1456 optval = OPTBIT(IN6P_HOPLIMIT); 1457 break; 1458 1459 case IPV6_RECVRTHDR: 1460 optval = OPTBIT(IN6P_RTHDR); 1461 break; 1462 1463 case IPV6_RECVPATHMTU: 1464 optval = OPTBIT(IN6P_MTU); 1465 break; 1466 1467 case IPV6_V6ONLY: 1468 optval = 1; 1469 break; 1470 1471 case IPV6_PORTRANGE: 1472 { 1473 int flags; 1474 flags = inp->inp_flags; 1475 if (flags & IN6P_HIGHPORT) 1476 optval = IPV6_PORTRANGE_HIGH; 1477 else if (flags & IN6P_LOWPORT) 1478 optval = IPV6_PORTRANGE_LOW; 1479 else 1480 optval = 0; 1481 break; 1482 } 1483 case IPV6_RECVTCLASS: 1484 optval = OPTBIT(IN6P_TCLASS); 1485 break; 1486 1487 case IPV6_AUTOFLOWLABEL: 1488 optval = OPTBIT(IN6P_AUTOFLOWLABEL); 1489 break; 1490 1491 case IPV6_RECVDSTPORT: 1492 optval = OPTBIT(IN6P_RECVDSTPORT); 1493 break; 1494 } 1495 if (error) 1496 break; 1497 m->m_len = sizeof(int); 1498 *mtod(m, int *) = optval; 1499 break; 1500 1501 case IPV6_PATHMTU: 1502 { 1503 u_long pmtu = 0; 1504 struct ip6_mtuinfo mtuinfo; 1505 struct ifnet *ifp; 1506 struct rtentry *rt; 1507 1508 if (!(so->so_state & SS_ISCONNECTED)) 1509 return (ENOTCONN); 1510 1511 rt = in_pcbrtentry(inp); 1512 if (!rtisvalid(rt)) 1513 return (EHOSTUNREACH); 1514 1515 ifp = if_get(rt->rt_ifidx); 1516 if (ifp == NULL) 1517 return (EHOSTUNREACH); 1518 /* 1519 * XXX: we dot not consider the case of source 1520 * routing, or optional information to specify 1521 * the outgoing interface. 1522 */ 1523 error = ip6_getpmtu(rt, ifp, &pmtu); 1524 if_put(ifp); 1525 if (error) 1526 break; 1527 if (pmtu > IPV6_MAXPACKET) 1528 pmtu = IPV6_MAXPACKET; 1529 1530 bzero(&mtuinfo, sizeof(mtuinfo)); 1531 mtuinfo.ip6m_mtu = (u_int32_t)pmtu; 1532 optdata = (void *)&mtuinfo; 1533 optdatalen = sizeof(mtuinfo); 1534 if (optdatalen > MCLBYTES) 1535 return (EMSGSIZE); /* XXX */ 1536 if (optdatalen > MLEN) 1537 MCLGET(m, M_WAIT); 1538 m->m_len = optdatalen; 1539 bcopy(optdata, mtod(m, void *), optdatalen); 1540 break; 1541 } 1542 1543 case IPV6_PKTINFO: 1544 case IPV6_HOPOPTS: 1545 case IPV6_RTHDR: 1546 case IPV6_DSTOPTS: 1547 case IPV6_RTHDRDSTOPTS: 1548 case IPV6_TCLASS: 1549 case IPV6_DONTFRAG: 1550 case IPV6_USE_MIN_MTU: 1551 error = ip6_getpcbopt(inp->inp_outputopts6, 1552 optname, m); 1553 break; 1554 1555 case IPV6_MULTICAST_IF: 1556 case IPV6_MULTICAST_HOPS: 1557 case IPV6_MULTICAST_LOOP: 1558 case IPV6_JOIN_GROUP: 1559 case IPV6_LEAVE_GROUP: 1560 error = ip6_getmoptions(optname, 1561 inp->inp_moptions6, m); 1562 break; 1563 1564 case IPSEC6_OUTSA: 1565 error = EINVAL; 1566 break; 1567 1568 case IPV6_AUTH_LEVEL: 1569 case IPV6_ESP_TRANS_LEVEL: 1570 case IPV6_ESP_NETWORK_LEVEL: 1571 case IPV6_IPCOMP_LEVEL: 1572 #ifndef IPSEC 1573 m->m_len = sizeof(int); 1574 *mtod(m, int *) = IPSEC_LEVEL_NONE; 1575 #else 1576 m->m_len = sizeof(int); 1577 switch (optname) { 1578 case IPV6_AUTH_LEVEL: 1579 optval = inp->inp_seclevel[SL_AUTH]; 1580 break; 1581 1582 case IPV6_ESP_TRANS_LEVEL: 1583 optval = 1584 inp->inp_seclevel[SL_ESP_TRANS]; 1585 break; 1586 1587 case IPV6_ESP_NETWORK_LEVEL: 1588 optval = 1589 inp->inp_seclevel[SL_ESP_NETWORK]; 1590 break; 1591 1592 case IPV6_IPCOMP_LEVEL: 1593 optval = inp->inp_seclevel[SL_IPCOMP]; 1594 break; 1595 } 1596 *mtod(m, int *) = optval; 1597 #endif 1598 break; 1599 case SO_RTABLE: 1600 m->m_len = sizeof(u_int); 1601 *mtod(m, u_int *) = inp->inp_rtableid; 1602 break; 1603 case IPV6_PIPEX: 1604 m->m_len = sizeof(int); 1605 *mtod(m, int *) = inp->inp_pipex; 1606 break; 1607 1608 default: 1609 error = ENOPROTOOPT; 1610 break; 1611 } 1612 break; 1613 } 1614 return (error); 1615 } 1616 1617 int 1618 ip6_raw_ctloutput(int op, struct socket *so, int level, int optname, 1619 struct mbuf *m) 1620 { 1621 int error = 0, optval; 1622 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); 1623 struct inpcb *inp = sotoinpcb(so); 1624 1625 if (level != IPPROTO_IPV6) 1626 return (EINVAL); 1627 1628 switch (optname) { 1629 case IPV6_CHECKSUM: 1630 /* 1631 * For ICMPv6 sockets, no modification allowed for checksum 1632 * offset, permit "no change" values to help existing apps. 1633 * 1634 * RFC3542 says: "An attempt to set IPV6_CHECKSUM 1635 * for an ICMPv6 socket will fail." 1636 * The current behavior does not meet RFC3542. 1637 */ 1638 switch (op) { 1639 case PRCO_SETOPT: 1640 if (m == NULL || m->m_len != sizeof(int)) { 1641 error = EINVAL; 1642 break; 1643 } 1644 optval = *mtod(m, int *); 1645 if (optval < -1 || 1646 (optval > 0 && (optval % 2) != 0)) { 1647 /* 1648 * The API assumes non-negative even offset 1649 * values or -1 as a special value. 1650 */ 1651 error = EINVAL; 1652 } else if (so->so_proto->pr_protocol == 1653 IPPROTO_ICMPV6) { 1654 if (optval != icmp6off) 1655 error = EINVAL; 1656 } else 1657 inp->inp_cksum6 = optval; 1658 break; 1659 1660 case PRCO_GETOPT: 1661 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) 1662 optval = icmp6off; 1663 else 1664 optval = inp->inp_cksum6; 1665 1666 m->m_len = sizeof(int); 1667 *mtod(m, int *) = optval; 1668 break; 1669 1670 default: 1671 error = EINVAL; 1672 break; 1673 } 1674 break; 1675 1676 default: 1677 error = ENOPROTOOPT; 1678 break; 1679 } 1680 1681 return (error); 1682 } 1683 1684 /* 1685 * initialize ip6_pktopts. beware that there are non-zero default values in 1686 * the struct. 1687 */ 1688 void 1689 ip6_initpktopts(struct ip6_pktopts *opt) 1690 { 1691 bzero(opt, sizeof(*opt)); 1692 opt->ip6po_hlim = -1; /* -1 means default hop limit */ 1693 opt->ip6po_tclass = -1; /* -1 means default traffic class */ 1694 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY; 1695 } 1696 1697 int 1698 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt, 1699 int priv, int uproto) 1700 { 1701 struct ip6_pktopts *opt; 1702 1703 if (*pktopt == NULL) { 1704 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT, 1705 M_WAITOK); 1706 ip6_initpktopts(*pktopt); 1707 } 1708 opt = *pktopt; 1709 1710 return (ip6_setpktopt(optname, buf, len, opt, priv, 1, uproto)); 1711 } 1712 1713 int 1714 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct mbuf *m) 1715 { 1716 void *optdata = NULL; 1717 int optdatalen = 0; 1718 struct ip6_ext *ip6e; 1719 int error = 0; 1720 struct in6_pktinfo null_pktinfo; 1721 int deftclass = 0, on; 1722 int defminmtu = IP6PO_MINMTU_MCASTONLY; 1723 1724 switch (optname) { 1725 case IPV6_PKTINFO: 1726 if (pktopt && pktopt->ip6po_pktinfo) 1727 optdata = (void *)pktopt->ip6po_pktinfo; 1728 else { 1729 /* XXX: we don't have to do this every time... */ 1730 bzero(&null_pktinfo, sizeof(null_pktinfo)); 1731 optdata = (void *)&null_pktinfo; 1732 } 1733 optdatalen = sizeof(struct in6_pktinfo); 1734 break; 1735 case IPV6_TCLASS: 1736 if (pktopt && pktopt->ip6po_tclass >= 0) 1737 optdata = (void *)&pktopt->ip6po_tclass; 1738 else 1739 optdata = (void *)&deftclass; 1740 optdatalen = sizeof(int); 1741 break; 1742 case IPV6_HOPOPTS: 1743 if (pktopt && pktopt->ip6po_hbh) { 1744 optdata = (void *)pktopt->ip6po_hbh; 1745 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh; 1746 optdatalen = (ip6e->ip6e_len + 1) << 3; 1747 } 1748 break; 1749 case IPV6_RTHDR: 1750 if (pktopt && pktopt->ip6po_rthdr) { 1751 optdata = (void *)pktopt->ip6po_rthdr; 1752 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr; 1753 optdatalen = (ip6e->ip6e_len + 1) << 3; 1754 } 1755 break; 1756 case IPV6_RTHDRDSTOPTS: 1757 if (pktopt && pktopt->ip6po_dest1) { 1758 optdata = (void *)pktopt->ip6po_dest1; 1759 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1; 1760 optdatalen = (ip6e->ip6e_len + 1) << 3; 1761 } 1762 break; 1763 case IPV6_DSTOPTS: 1764 if (pktopt && pktopt->ip6po_dest2) { 1765 optdata = (void *)pktopt->ip6po_dest2; 1766 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2; 1767 optdatalen = (ip6e->ip6e_len + 1) << 3; 1768 } 1769 break; 1770 case IPV6_USE_MIN_MTU: 1771 if (pktopt) 1772 optdata = (void *)&pktopt->ip6po_minmtu; 1773 else 1774 optdata = (void *)&defminmtu; 1775 optdatalen = sizeof(int); 1776 break; 1777 case IPV6_DONTFRAG: 1778 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG)) 1779 on = 1; 1780 else 1781 on = 0; 1782 optdata = (void *)&on; 1783 optdatalen = sizeof(on); 1784 break; 1785 default: /* should not happen */ 1786 #ifdef DIAGNOSTIC 1787 panic("%s: unexpected option", __func__); 1788 #endif 1789 return (ENOPROTOOPT); 1790 } 1791 1792 if (optdatalen > MCLBYTES) 1793 return (EMSGSIZE); /* XXX */ 1794 if (optdatalen > MLEN) 1795 MCLGET(m, M_WAIT); 1796 m->m_len = optdatalen; 1797 if (optdatalen) 1798 bcopy(optdata, mtod(m, void *), optdatalen); 1799 1800 return (error); 1801 } 1802 1803 void 1804 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname) 1805 { 1806 if (optname == -1 || optname == IPV6_PKTINFO) { 1807 if (pktopt->ip6po_pktinfo) 1808 free(pktopt->ip6po_pktinfo, M_IP6OPT, 0); 1809 pktopt->ip6po_pktinfo = NULL; 1810 } 1811 if (optname == -1 || optname == IPV6_HOPLIMIT) 1812 pktopt->ip6po_hlim = -1; 1813 if (optname == -1 || optname == IPV6_TCLASS) 1814 pktopt->ip6po_tclass = -1; 1815 if (optname == -1 || optname == IPV6_HOPOPTS) { 1816 if (pktopt->ip6po_hbh) 1817 free(pktopt->ip6po_hbh, M_IP6OPT, 0); 1818 pktopt->ip6po_hbh = NULL; 1819 } 1820 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) { 1821 if (pktopt->ip6po_dest1) 1822 free(pktopt->ip6po_dest1, M_IP6OPT, 0); 1823 pktopt->ip6po_dest1 = NULL; 1824 } 1825 if (optname == -1 || optname == IPV6_RTHDR) { 1826 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr) 1827 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT, 0); 1828 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL; 1829 if (pktopt->ip6po_route.ro_rt) { 1830 rtfree(pktopt->ip6po_route.ro_rt); 1831 pktopt->ip6po_route.ro_rt = NULL; 1832 } 1833 } 1834 if (optname == -1 || optname == IPV6_DSTOPTS) { 1835 if (pktopt->ip6po_dest2) 1836 free(pktopt->ip6po_dest2, M_IP6OPT, 0); 1837 pktopt->ip6po_dest2 = NULL; 1838 } 1839 } 1840 1841 #define PKTOPT_EXTHDRCPY(type) \ 1842 do {\ 1843 if (src->type) {\ 1844 size_t hlen;\ 1845 hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\ 1846 dst->type = malloc(hlen, M_IP6OPT, M_NOWAIT);\ 1847 if (dst->type == NULL)\ 1848 goto bad;\ 1849 memcpy(dst->type, src->type, hlen);\ 1850 }\ 1851 } while (/*CONSTCOND*/ 0) 1852 1853 int 1854 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src) 1855 { 1856 dst->ip6po_hlim = src->ip6po_hlim; 1857 dst->ip6po_tclass = src->ip6po_tclass; 1858 dst->ip6po_flags = src->ip6po_flags; 1859 if (src->ip6po_pktinfo) { 1860 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo), 1861 M_IP6OPT, M_NOWAIT); 1862 if (dst->ip6po_pktinfo == NULL) 1863 goto bad; 1864 *dst->ip6po_pktinfo = *src->ip6po_pktinfo; 1865 } 1866 PKTOPT_EXTHDRCPY(ip6po_hbh); 1867 PKTOPT_EXTHDRCPY(ip6po_dest1); 1868 PKTOPT_EXTHDRCPY(ip6po_dest2); 1869 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */ 1870 return (0); 1871 1872 bad: 1873 ip6_clearpktopts(dst, -1); 1874 return (ENOBUFS); 1875 } 1876 #undef PKTOPT_EXTHDRCPY 1877 1878 void 1879 ip6_freepcbopts(struct ip6_pktopts *pktopt) 1880 { 1881 if (pktopt == NULL) 1882 return; 1883 1884 ip6_clearpktopts(pktopt, -1); 1885 1886 free(pktopt, M_IP6OPT, 0); 1887 } 1888 1889 /* 1890 * Set the IP6 multicast options in response to user setsockopt(). 1891 */ 1892 int 1893 ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m, 1894 unsigned int rtableid) 1895 { 1896 int error = 0; 1897 u_int loop, ifindex; 1898 struct ipv6_mreq *mreq; 1899 struct ifnet *ifp; 1900 struct ip6_moptions *im6o = *im6op; 1901 struct in6_multi_mship *imm; 1902 struct proc *p = curproc; /* XXX */ 1903 1904 if (im6o == NULL) { 1905 /* 1906 * No multicast option buffer attached to the pcb; 1907 * allocate one and initialize to default values. 1908 */ 1909 im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK); 1910 if (im6o == NULL) 1911 return (ENOBUFS); 1912 *im6op = im6o; 1913 im6o->im6o_ifidx = 0; 1914 im6o->im6o_hlim = ip6_defmcasthlim; 1915 im6o->im6o_loop = IPV6_DEFAULT_MULTICAST_LOOP; 1916 LIST_INIT(&im6o->im6o_memberships); 1917 } 1918 1919 switch (optname) { 1920 1921 case IPV6_MULTICAST_IF: 1922 /* 1923 * Select the interface for outgoing multicast packets. 1924 */ 1925 if (m == NULL || m->m_len != sizeof(u_int)) { 1926 error = EINVAL; 1927 break; 1928 } 1929 memcpy(&ifindex, mtod(m, u_int *), sizeof(ifindex)); 1930 if (ifindex != 0) { 1931 ifp = if_get(ifindex); 1932 if (ifp == NULL) { 1933 error = ENXIO; /* XXX EINVAL? */ 1934 break; 1935 } 1936 if (ifp->if_rdomain != rtable_l2(rtableid) || 1937 (ifp->if_flags & IFF_MULTICAST) == 0) { 1938 error = EADDRNOTAVAIL; 1939 if_put(ifp); 1940 break; 1941 } 1942 if_put(ifp); 1943 } 1944 im6o->im6o_ifidx = ifindex; 1945 break; 1946 1947 case IPV6_MULTICAST_HOPS: 1948 { 1949 /* 1950 * Set the IP6 hoplimit for outgoing multicast packets. 1951 */ 1952 int optval; 1953 if (m == NULL || m->m_len != sizeof(int)) { 1954 error = EINVAL; 1955 break; 1956 } 1957 memcpy(&optval, mtod(m, u_int *), sizeof(optval)); 1958 if (optval < -1 || optval >= 256) 1959 error = EINVAL; 1960 else if (optval == -1) 1961 im6o->im6o_hlim = ip6_defmcasthlim; 1962 else 1963 im6o->im6o_hlim = optval; 1964 break; 1965 } 1966 1967 case IPV6_MULTICAST_LOOP: 1968 /* 1969 * Set the loopback flag for outgoing multicast packets. 1970 * Must be zero or one. 1971 */ 1972 if (m == NULL || m->m_len != sizeof(u_int)) { 1973 error = EINVAL; 1974 break; 1975 } 1976 memcpy(&loop, mtod(m, u_int *), sizeof(loop)); 1977 if (loop > 1) { 1978 error = EINVAL; 1979 break; 1980 } 1981 im6o->im6o_loop = loop; 1982 break; 1983 1984 case IPV6_JOIN_GROUP: 1985 /* 1986 * Add a multicast group membership. 1987 * Group must be a valid IP6 multicast address. 1988 */ 1989 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { 1990 error = EINVAL; 1991 break; 1992 } 1993 mreq = mtod(m, struct ipv6_mreq *); 1994 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { 1995 /* 1996 * We use the unspecified address to specify to accept 1997 * all multicast addresses. Only super user is allowed 1998 * to do this. 1999 */ 2000 if (suser(p)) 2001 { 2002 error = EACCES; 2003 break; 2004 } 2005 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { 2006 error = EINVAL; 2007 break; 2008 } 2009 2010 /* 2011 * If no interface was explicitly specified, choose an 2012 * appropriate one according to the given multicast address. 2013 */ 2014 if (mreq->ipv6mr_interface == 0) { 2015 struct rtentry *rt; 2016 struct sockaddr_in6 dst; 2017 2018 memset(&dst, 0, sizeof(dst)); 2019 dst.sin6_len = sizeof(dst); 2020 dst.sin6_family = AF_INET6; 2021 dst.sin6_addr = mreq->ipv6mr_multiaddr; 2022 rt = rtalloc(sin6tosa(&dst), RT_RESOLVE, rtableid); 2023 if (rt == NULL) { 2024 error = EADDRNOTAVAIL; 2025 break; 2026 } 2027 ifp = if_get(rt->rt_ifidx); 2028 rtfree(rt); 2029 } else { 2030 /* 2031 * If the interface is specified, validate it. 2032 */ 2033 ifp = if_get(mreq->ipv6mr_interface); 2034 if (ifp == NULL) { 2035 error = ENXIO; /* XXX EINVAL? */ 2036 break; 2037 } 2038 } 2039 2040 /* 2041 * See if we found an interface, and confirm that it 2042 * supports multicast 2043 */ 2044 if (ifp == NULL || ifp->if_rdomain != rtable_l2(rtableid) || 2045 (ifp->if_flags & IFF_MULTICAST) == 0) { 2046 if_put(ifp); 2047 error = EADDRNOTAVAIL; 2048 break; 2049 } 2050 /* 2051 * Put interface index into the multicast address, 2052 * if the address has link/interface-local scope. 2053 */ 2054 if (IN6_IS_SCOPE_EMBED(&mreq->ipv6mr_multiaddr)) { 2055 mreq->ipv6mr_multiaddr.s6_addr16[1] = 2056 htons(ifp->if_index); 2057 } 2058 /* 2059 * See if the membership already exists. 2060 */ 2061 LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) 2062 if (imm->i6mm_maddr->in6m_ifidx == ifp->if_index && 2063 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2064 &mreq->ipv6mr_multiaddr)) 2065 break; 2066 if (imm != NULL) { 2067 if_put(ifp); 2068 error = EADDRINUSE; 2069 break; 2070 } 2071 /* 2072 * Everything looks good; add a new record to the multicast 2073 * address list for the given interface. 2074 */ 2075 imm = in6_joingroup(ifp, &mreq->ipv6mr_multiaddr, &error); 2076 if_put(ifp); 2077 if (!imm) 2078 break; 2079 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); 2080 break; 2081 2082 case IPV6_LEAVE_GROUP: 2083 /* 2084 * Drop a multicast group membership. 2085 * Group must be a valid IP6 multicast address. 2086 */ 2087 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { 2088 error = EINVAL; 2089 break; 2090 } 2091 mreq = mtod(m, struct ipv6_mreq *); 2092 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { 2093 if (suser(p)) { 2094 error = EACCES; 2095 break; 2096 } 2097 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { 2098 error = EINVAL; 2099 break; 2100 } 2101 2102 /* 2103 * Put interface index into the multicast address, 2104 * if the address has link-local scope. 2105 */ 2106 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) { 2107 mreq->ipv6mr_multiaddr.s6_addr16[1] = 2108 htons(mreq->ipv6mr_interface); 2109 } 2110 2111 /* 2112 * If an interface address was specified, get a pointer 2113 * to its ifnet structure. 2114 */ 2115 if (mreq->ipv6mr_interface == 0) 2116 ifp = NULL; 2117 else { 2118 ifp = if_get(mreq->ipv6mr_interface); 2119 if (ifp == NULL) { 2120 error = ENXIO; /* XXX EINVAL? */ 2121 break; 2122 } 2123 } 2124 2125 /* 2126 * Find the membership in the membership list. 2127 */ 2128 LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) { 2129 if ((ifp == NULL || 2130 imm->i6mm_maddr->in6m_ifidx == ifp->if_index) && 2131 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2132 &mreq->ipv6mr_multiaddr)) 2133 break; 2134 } 2135 2136 if_put(ifp); 2137 2138 if (imm == NULL) { 2139 /* Unable to resolve interface */ 2140 error = EADDRNOTAVAIL; 2141 break; 2142 } 2143 /* 2144 * Give up the multicast address record to which the 2145 * membership points. 2146 */ 2147 LIST_REMOVE(imm, i6mm_chain); 2148 in6_leavegroup(imm); 2149 break; 2150 2151 default: 2152 error = EOPNOTSUPP; 2153 break; 2154 } 2155 2156 /* 2157 * If all options have default values, no need to keep the option 2158 * structure. 2159 */ 2160 if (im6o->im6o_ifidx == 0 && 2161 im6o->im6o_hlim == ip6_defmcasthlim && 2162 im6o->im6o_loop == IPV6_DEFAULT_MULTICAST_LOOP && 2163 LIST_EMPTY(&im6o->im6o_memberships)) { 2164 free(*im6op, M_IPMOPTS, sizeof(**im6op)); 2165 *im6op = NULL; 2166 } 2167 2168 return (error); 2169 } 2170 2171 /* 2172 * Return the IP6 multicast options in response to user getsockopt(). 2173 */ 2174 int 2175 ip6_getmoptions(int optname, struct ip6_moptions *im6o, struct mbuf *m) 2176 { 2177 u_int *hlim, *loop, *ifindex; 2178 2179 switch (optname) { 2180 case IPV6_MULTICAST_IF: 2181 ifindex = mtod(m, u_int *); 2182 m->m_len = sizeof(u_int); 2183 if (im6o == NULL || im6o->im6o_ifidx == 0) 2184 *ifindex = 0; 2185 else 2186 *ifindex = im6o->im6o_ifidx; 2187 return (0); 2188 2189 case IPV6_MULTICAST_HOPS: 2190 hlim = mtod(m, u_int *); 2191 m->m_len = sizeof(u_int); 2192 if (im6o == NULL) 2193 *hlim = ip6_defmcasthlim; 2194 else 2195 *hlim = im6o->im6o_hlim; 2196 return (0); 2197 2198 case IPV6_MULTICAST_LOOP: 2199 loop = mtod(m, u_int *); 2200 m->m_len = sizeof(u_int); 2201 if (im6o == NULL) 2202 *loop = ip6_defmcasthlim; 2203 else 2204 *loop = im6o->im6o_loop; 2205 return (0); 2206 2207 default: 2208 return (EOPNOTSUPP); 2209 } 2210 } 2211 2212 /* 2213 * Discard the IP6 multicast options. 2214 */ 2215 void 2216 ip6_freemoptions(struct ip6_moptions *im6o) 2217 { 2218 struct in6_multi_mship *imm; 2219 2220 if (im6o == NULL) 2221 return; 2222 2223 while (!LIST_EMPTY(&im6o->im6o_memberships)) { 2224 imm = LIST_FIRST(&im6o->im6o_memberships); 2225 LIST_REMOVE(imm, i6mm_chain); 2226 in6_leavegroup(imm); 2227 } 2228 free(im6o, M_IPMOPTS, sizeof(*im6o)); 2229 } 2230 2231 /* 2232 * Set IPv6 outgoing packet options based on advanced API. 2233 */ 2234 int 2235 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt, 2236 struct ip6_pktopts *stickyopt, int priv, int uproto) 2237 { 2238 u_int clen; 2239 struct cmsghdr *cm = 0; 2240 caddr_t cmsgs; 2241 int error; 2242 2243 if (control == NULL || opt == NULL) 2244 return (EINVAL); 2245 2246 ip6_initpktopts(opt); 2247 if (stickyopt) { 2248 int error; 2249 2250 /* 2251 * If stickyopt is provided, make a local copy of the options 2252 * for this particular packet, then override them by ancillary 2253 * objects. 2254 * XXX: copypktopts() does not copy the cached route to a next 2255 * hop (if any). This is not very good in terms of efficiency, 2256 * but we can allow this since this option should be rarely 2257 * used. 2258 */ 2259 if ((error = copypktopts(opt, stickyopt)) != 0) 2260 return (error); 2261 } 2262 2263 /* 2264 * XXX: Currently, we assume all the optional information is stored 2265 * in a single mbuf. 2266 */ 2267 if (control->m_next) 2268 return (EINVAL); 2269 2270 clen = control->m_len; 2271 cmsgs = mtod(control, caddr_t); 2272 do { 2273 if (clen < CMSG_LEN(0)) 2274 return (EINVAL); 2275 cm = (struct cmsghdr *)cmsgs; 2276 if (cm->cmsg_len < CMSG_LEN(0) || cm->cmsg_len > clen || 2277 CMSG_ALIGN(cm->cmsg_len) > clen) 2278 return (EINVAL); 2279 if (cm->cmsg_level == IPPROTO_IPV6) { 2280 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm), 2281 cm->cmsg_len - CMSG_LEN(0), opt, priv, 0, uproto); 2282 if (error) 2283 return (error); 2284 } 2285 2286 clen -= CMSG_ALIGN(cm->cmsg_len); 2287 cmsgs += CMSG_ALIGN(cm->cmsg_len); 2288 } while (clen); 2289 2290 return (0); 2291 } 2292 2293 /* 2294 * Set a particular packet option, as a sticky option or an ancillary data 2295 * item. "len" can be 0 only when it's a sticky option. 2296 */ 2297 int 2298 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt, 2299 int priv, int sticky, int uproto) 2300 { 2301 int minmtupolicy; 2302 2303 switch (optname) { 2304 case IPV6_PKTINFO: 2305 { 2306 struct ifnet *ifp = NULL; 2307 struct in6_pktinfo *pktinfo; 2308 2309 if (len != sizeof(struct in6_pktinfo)) 2310 return (EINVAL); 2311 2312 pktinfo = (struct in6_pktinfo *)buf; 2313 2314 /* 2315 * An application can clear any sticky IPV6_PKTINFO option by 2316 * doing a "regular" setsockopt with ipi6_addr being 2317 * in6addr_any and ipi6_ifindex being zero. 2318 * [RFC 3542, Section 6] 2319 */ 2320 if (opt->ip6po_pktinfo && 2321 pktinfo->ipi6_ifindex == 0 && 2322 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2323 ip6_clearpktopts(opt, optname); 2324 break; 2325 } 2326 2327 if (uproto == IPPROTO_TCP && 2328 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2329 return (EINVAL); 2330 } 2331 2332 if (pktinfo->ipi6_ifindex) { 2333 ifp = if_get(pktinfo->ipi6_ifindex); 2334 if (ifp == NULL) 2335 return (ENXIO); 2336 if_put(ifp); 2337 } 2338 2339 /* 2340 * We store the address anyway, and let in6_selectsrc() 2341 * validate the specified address. This is because ipi6_addr 2342 * may not have enough information about its scope zone, and 2343 * we may need additional information (such as outgoing 2344 * interface or the scope zone of a destination address) to 2345 * disambiguate the scope. 2346 * XXX: the delay of the validation may confuse the 2347 * application when it is used as a sticky option. 2348 */ 2349 if (opt->ip6po_pktinfo == NULL) { 2350 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo), 2351 M_IP6OPT, M_NOWAIT); 2352 if (opt->ip6po_pktinfo == NULL) 2353 return (ENOBUFS); 2354 } 2355 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo)); 2356 break; 2357 } 2358 2359 case IPV6_HOPLIMIT: 2360 { 2361 int *hlimp; 2362 2363 /* 2364 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT 2365 * to simplify the ordering among hoplimit options. 2366 */ 2367 if (sticky) 2368 return (ENOPROTOOPT); 2369 2370 if (len != sizeof(int)) 2371 return (EINVAL); 2372 hlimp = (int *)buf; 2373 if (*hlimp < -1 || *hlimp > 255) 2374 return (EINVAL); 2375 2376 opt->ip6po_hlim = *hlimp; 2377 break; 2378 } 2379 2380 case IPV6_TCLASS: 2381 { 2382 int tclass; 2383 2384 if (len != sizeof(int)) 2385 return (EINVAL); 2386 tclass = *(int *)buf; 2387 if (tclass < -1 || tclass > 255) 2388 return (EINVAL); 2389 2390 opt->ip6po_tclass = tclass; 2391 break; 2392 } 2393 case IPV6_HOPOPTS: 2394 { 2395 struct ip6_hbh *hbh; 2396 int hbhlen; 2397 2398 /* 2399 * XXX: We don't allow a non-privileged user to set ANY HbH 2400 * options, since per-option restriction has too much 2401 * overhead. 2402 */ 2403 if (!priv) 2404 return (EPERM); 2405 2406 if (len == 0) { 2407 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2408 break; /* just remove the option */ 2409 } 2410 2411 /* message length validation */ 2412 if (len < sizeof(struct ip6_hbh)) 2413 return (EINVAL); 2414 hbh = (struct ip6_hbh *)buf; 2415 hbhlen = (hbh->ip6h_len + 1) << 3; 2416 if (len != hbhlen) 2417 return (EINVAL); 2418 2419 /* turn off the previous option, then set the new option. */ 2420 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2421 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT); 2422 if (opt->ip6po_hbh == NULL) 2423 return (ENOBUFS); 2424 memcpy(opt->ip6po_hbh, hbh, hbhlen); 2425 2426 break; 2427 } 2428 2429 case IPV6_DSTOPTS: 2430 case IPV6_RTHDRDSTOPTS: 2431 { 2432 struct ip6_dest *dest, **newdest = NULL; 2433 int destlen; 2434 2435 if (!priv) /* XXX: see the comment for IPV6_HOPOPTS */ 2436 return (EPERM); 2437 2438 if (len == 0) { 2439 ip6_clearpktopts(opt, optname); 2440 break; /* just remove the option */ 2441 } 2442 2443 /* message length validation */ 2444 if (len < sizeof(struct ip6_dest)) 2445 return (EINVAL); 2446 dest = (struct ip6_dest *)buf; 2447 destlen = (dest->ip6d_len + 1) << 3; 2448 if (len != destlen) 2449 return (EINVAL); 2450 /* 2451 * Determine the position that the destination options header 2452 * should be inserted; before or after the routing header. 2453 */ 2454 switch (optname) { 2455 case IPV6_RTHDRDSTOPTS: 2456 newdest = &opt->ip6po_dest1; 2457 break; 2458 case IPV6_DSTOPTS: 2459 newdest = &opt->ip6po_dest2; 2460 break; 2461 } 2462 2463 /* turn off the previous option, then set the new option. */ 2464 ip6_clearpktopts(opt, optname); 2465 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT); 2466 if (*newdest == NULL) 2467 return (ENOBUFS); 2468 memcpy(*newdest, dest, destlen); 2469 2470 break; 2471 } 2472 2473 case IPV6_RTHDR: 2474 { 2475 struct ip6_rthdr *rth; 2476 int rthlen; 2477 2478 if (len == 0) { 2479 ip6_clearpktopts(opt, IPV6_RTHDR); 2480 break; /* just remove the option */ 2481 } 2482 2483 /* message length validation */ 2484 if (len < sizeof(struct ip6_rthdr)) 2485 return (EINVAL); 2486 rth = (struct ip6_rthdr *)buf; 2487 rthlen = (rth->ip6r_len + 1) << 3; 2488 if (len != rthlen) 2489 return (EINVAL); 2490 2491 switch (rth->ip6r_type) { 2492 case IPV6_RTHDR_TYPE_0: 2493 if (rth->ip6r_len == 0) /* must contain one addr */ 2494 return (EINVAL); 2495 if (rth->ip6r_len % 2) /* length must be even */ 2496 return (EINVAL); 2497 if (rth->ip6r_len / 2 != rth->ip6r_segleft) 2498 return (EINVAL); 2499 break; 2500 default: 2501 return (EINVAL); /* not supported */ 2502 } 2503 /* turn off the previous option */ 2504 ip6_clearpktopts(opt, IPV6_RTHDR); 2505 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT); 2506 if (opt->ip6po_rthdr == NULL) 2507 return (ENOBUFS); 2508 memcpy(opt->ip6po_rthdr, rth, rthlen); 2509 break; 2510 } 2511 2512 case IPV6_USE_MIN_MTU: 2513 if (len != sizeof(int)) 2514 return (EINVAL); 2515 minmtupolicy = *(int *)buf; 2516 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY && 2517 minmtupolicy != IP6PO_MINMTU_DISABLE && 2518 minmtupolicy != IP6PO_MINMTU_ALL) { 2519 return (EINVAL); 2520 } 2521 opt->ip6po_minmtu = minmtupolicy; 2522 break; 2523 2524 case IPV6_DONTFRAG: 2525 if (len != sizeof(int)) 2526 return (EINVAL); 2527 2528 if (uproto == IPPROTO_TCP || *(int *)buf == 0) { 2529 /* 2530 * we ignore this option for TCP sockets. 2531 * (RFC3542 leaves this case unspecified.) 2532 */ 2533 opt->ip6po_flags &= ~IP6PO_DONTFRAG; 2534 } else 2535 opt->ip6po_flags |= IP6PO_DONTFRAG; 2536 break; 2537 2538 default: 2539 return (ENOPROTOOPT); 2540 } /* end of switch */ 2541 2542 return (0); 2543 } 2544 2545 /* 2546 * Routine called from ip6_output() to loop back a copy of an IP6 multicast 2547 * packet to the input queue of a specified interface. 2548 */ 2549 void 2550 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in6 *dst) 2551 { 2552 struct mbuf *copym; 2553 struct ip6_hdr *ip6; 2554 2555 /* 2556 * Duplicate the packet. 2557 */ 2558 copym = m_copym(m, 0, M_COPYALL, M_NOWAIT); 2559 if (copym == NULL) 2560 return; 2561 2562 /* 2563 * Make sure to deep-copy IPv6 header portion in case the data 2564 * is in an mbuf cluster, so that we can safely override the IPv6 2565 * header portion later. 2566 */ 2567 if ((copym->m_flags & M_EXT) != 0 || 2568 copym->m_len < sizeof(struct ip6_hdr)) { 2569 copym = m_pullup(copym, sizeof(struct ip6_hdr)); 2570 if (copym == NULL) 2571 return; 2572 } 2573 2574 #ifdef DIAGNOSTIC 2575 if (copym->m_len < sizeof(*ip6)) { 2576 m_freem(copym); 2577 return; 2578 } 2579 #endif 2580 2581 ip6 = mtod(copym, struct ip6_hdr *); 2582 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 2583 ip6->ip6_src.s6_addr16[1] = 0; 2584 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 2585 ip6->ip6_dst.s6_addr16[1] = 0; 2586 2587 if_input_local(ifp, copym, dst->sin6_family); 2588 } 2589 2590 /* 2591 * Chop IPv6 header off from the payload. 2592 */ 2593 int 2594 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs) 2595 { 2596 struct mbuf *mh; 2597 struct ip6_hdr *ip6; 2598 2599 ip6 = mtod(m, struct ip6_hdr *); 2600 if (m->m_len > sizeof(*ip6)) { 2601 MGET(mh, M_DONTWAIT, MT_HEADER); 2602 if (mh == NULL) { 2603 m_freem(m); 2604 return ENOBUFS; 2605 } 2606 M_MOVE_PKTHDR(mh, m); 2607 m_align(mh, sizeof(*ip6)); 2608 m->m_len -= sizeof(*ip6); 2609 m->m_data += sizeof(*ip6); 2610 mh->m_next = m; 2611 m = mh; 2612 m->m_len = sizeof(*ip6); 2613 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6)); 2614 } 2615 exthdrs->ip6e_ip6 = m; 2616 return 0; 2617 } 2618 2619 u_int32_t 2620 ip6_randomid(void) 2621 { 2622 return idgen32(&ip6_id_ctx); 2623 } 2624 2625 void 2626 ip6_randomid_init(void) 2627 { 2628 idgen32_init(&ip6_id_ctx); 2629 } 2630 2631 /* 2632 * Compute significant parts of the IPv6 checksum pseudo-header 2633 * for use in a delayed TCP/UDP checksum calculation. 2634 */ 2635 static __inline u_int16_t __attribute__((__unused__)) 2636 in6_cksum_phdr(const struct in6_addr *src, const struct in6_addr *dst, 2637 u_int32_t len, u_int32_t nxt) 2638 { 2639 u_int32_t sum = 0; 2640 const u_int16_t *w; 2641 2642 w = (const u_int16_t *) src; 2643 sum += w[0]; 2644 if (!IN6_IS_SCOPE_EMBED(src)) 2645 sum += w[1]; 2646 sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5]; 2647 sum += w[6]; sum += w[7]; 2648 2649 w = (const u_int16_t *) dst; 2650 sum += w[0]; 2651 if (!IN6_IS_SCOPE_EMBED(dst)) 2652 sum += w[1]; 2653 sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5]; 2654 sum += w[6]; sum += w[7]; 2655 2656 sum += (u_int16_t)(len >> 16) + (u_int16_t)(len /*& 0xffff*/); 2657 2658 sum += (u_int16_t)(nxt >> 16) + (u_int16_t)(nxt /*& 0xffff*/); 2659 2660 sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/); 2661 2662 if (sum > 0xffff) 2663 sum -= 0xffff; 2664 2665 return (sum); 2666 } 2667 2668 /* 2669 * Process a delayed payload checksum calculation. 2670 */ 2671 void 2672 in6_delayed_cksum(struct mbuf *m, u_int8_t nxt) 2673 { 2674 int nxtp, offset; 2675 u_int16_t csum; 2676 2677 offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxtp); 2678 if (offset <= 0 || nxtp != nxt) 2679 /* If the desired next protocol isn't found, punt. */ 2680 return; 2681 csum = (u_int16_t)(in6_cksum(m, 0, offset, m->m_pkthdr.len - offset)); 2682 2683 switch (nxt) { 2684 case IPPROTO_TCP: 2685 offset += offsetof(struct tcphdr, th_sum); 2686 break; 2687 2688 case IPPROTO_UDP: 2689 offset += offsetof(struct udphdr, uh_sum); 2690 if (csum == 0) 2691 csum = 0xffff; 2692 break; 2693 2694 case IPPROTO_ICMPV6: 2695 offset += offsetof(struct icmp6_hdr, icmp6_cksum); 2696 break; 2697 } 2698 2699 if ((offset + sizeof(u_int16_t)) > m->m_len) 2700 m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT); 2701 else 2702 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; 2703 } 2704 2705 void 2706 in6_proto_cksum_out(struct mbuf *m, struct ifnet *ifp) 2707 { 2708 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2709 2710 /* some hw and in6_delayed_cksum need the pseudo header cksum */ 2711 if (m->m_pkthdr.csum_flags & 2712 (M_TCP_CSUM_OUT|M_UDP_CSUM_OUT|M_ICMP_CSUM_OUT)) { 2713 int nxt, offset; 2714 u_int16_t csum; 2715 2716 offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 2717 csum = in6_cksum_phdr(&ip6->ip6_src, &ip6->ip6_dst, 2718 htonl(m->m_pkthdr.len - offset), htonl(nxt)); 2719 if (nxt == IPPROTO_TCP) 2720 offset += offsetof(struct tcphdr, th_sum); 2721 else if (nxt == IPPROTO_UDP) 2722 offset += offsetof(struct udphdr, uh_sum); 2723 else if (nxt == IPPROTO_ICMPV6) 2724 offset += offsetof(struct icmp6_hdr, icmp6_cksum); 2725 if ((offset + sizeof(u_int16_t)) > m->m_len) 2726 m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT); 2727 else 2728 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; 2729 } 2730 2731 if (m->m_pkthdr.csum_flags & M_TCP_CSUM_OUT) { 2732 if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_TCPv6) || 2733 ip6->ip6_nxt != IPPROTO_TCP || 2734 ifp->if_bridgeidx != 0) { 2735 tcpstat_inc(tcps_outswcsum); 2736 in6_delayed_cksum(m, IPPROTO_TCP); 2737 m->m_pkthdr.csum_flags &= ~M_TCP_CSUM_OUT; /* Clear */ 2738 } 2739 } else if (m->m_pkthdr.csum_flags & M_UDP_CSUM_OUT) { 2740 if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_UDPv6) || 2741 ip6->ip6_nxt != IPPROTO_UDP || 2742 ifp->if_bridgeidx != 0) { 2743 udpstat_inc(udps_outswcsum); 2744 in6_delayed_cksum(m, IPPROTO_UDP); 2745 m->m_pkthdr.csum_flags &= ~M_UDP_CSUM_OUT; /* Clear */ 2746 } 2747 } else if (m->m_pkthdr.csum_flags & M_ICMP_CSUM_OUT) { 2748 in6_delayed_cksum(m, IPPROTO_ICMPV6); 2749 m->m_pkthdr.csum_flags &= ~M_ICMP_CSUM_OUT; /* Clear */ 2750 } 2751 } 2752 2753 #ifdef IPSEC 2754 int 2755 ip6_output_ipsec_lookup(struct mbuf *m, struct inpcb *inp, struct tdb **tdbout) 2756 { 2757 struct tdb *tdb; 2758 struct m_tag *mtag; 2759 struct tdb_ident *tdbi; 2760 int error; 2761 2762 /* 2763 * Check if there was an outgoing SA bound to the flow 2764 * from a transport protocol. 2765 */ 2766 2767 /* Do we have any pending SAs to apply ? */ 2768 error = ipsp_spd_lookup(m, AF_INET6, sizeof(struct ip6_hdr), 2769 IPSP_DIRECTION_OUT, NULL, inp, &tdb, NULL); 2770 if (error || tdb == NULL) { 2771 *tdbout = NULL; 2772 return error; 2773 } 2774 /* Loop detection */ 2775 for (mtag = m_tag_first(m); mtag != NULL; mtag = m_tag_next(m, mtag)) { 2776 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE) 2777 continue; 2778 tdbi = (struct tdb_ident *)(mtag + 1); 2779 if (tdbi->spi == tdb->tdb_spi && 2780 tdbi->proto == tdb->tdb_sproto && 2781 tdbi->rdomain == tdb->tdb_rdomain && 2782 !memcmp(&tdbi->dst, &tdb->tdb_dst, 2783 sizeof(union sockaddr_union))) { 2784 /* no IPsec needed */ 2785 tdb_unref(tdb); 2786 *tdbout = NULL; 2787 return 0; 2788 } 2789 } 2790 *tdbout = tdb; 2791 return 0; 2792 } 2793 2794 int 2795 ip6_output_ipsec_pmtu_update(struct tdb *tdb, struct route_in6 *ro, 2796 struct in6_addr *dst, int ifidx, int rtableid, int transportmode) 2797 { 2798 struct rtentry *rt = NULL; 2799 int rt_mtucloned = 0; 2800 2801 /* Find a host route to store the mtu in */ 2802 if (ro != NULL) 2803 rt = ro->ro_rt; 2804 /* but don't add a PMTU route for transport mode SAs */ 2805 if (transportmode) 2806 rt = NULL; 2807 else if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0) { 2808 struct sockaddr_in6 sin6; 2809 int error; 2810 2811 memset(&sin6, 0, sizeof(sin6)); 2812 sin6.sin6_family = AF_INET6; 2813 sin6.sin6_len = sizeof(sin6); 2814 sin6.sin6_addr = *dst; 2815 sin6.sin6_scope_id = in6_addr2scopeid(ifidx, dst); 2816 error = in6_embedscope(dst, &sin6, NULL); 2817 if (error) { 2818 /* should be impossible */ 2819 return error; 2820 } 2821 rt = icmp6_mtudisc_clone(&sin6, rtableid, 1); 2822 rt_mtucloned = 1; 2823 } 2824 DPRINTF("spi %08x mtu %d rt %p cloned %d", 2825 ntohl(tdb->tdb_spi), tdb->tdb_mtu, rt, rt_mtucloned); 2826 if (rt != NULL) { 2827 rt->rt_mtu = tdb->tdb_mtu; 2828 if (ro != NULL && ro->ro_rt != NULL) { 2829 rtfree(ro->ro_rt); 2830 ro->ro_rt = rtalloc(sin6tosa(&ro->ro_dst), RT_RESOLVE, 2831 rtableid); 2832 } 2833 if (rt_mtucloned) 2834 rtfree(rt); 2835 } 2836 return 0; 2837 } 2838 2839 int 2840 ip6_output_ipsec_send(struct tdb *tdb, struct mbuf *m, struct route_in6 *ro, 2841 int tunalready, int fwd) 2842 { 2843 #if NPF > 0 2844 struct ifnet *encif; 2845 #endif 2846 struct ip6_hdr *ip6; 2847 struct in6_addr dst; 2848 int error, ifidx, rtableid; 2849 2850 #if NPF > 0 2851 /* 2852 * Packet filter 2853 */ 2854 if ((encif = enc_getif(tdb->tdb_rdomain, tdb->tdb_tap)) == NULL || 2855 pf_test(AF_INET6, fwd ? PF_FWD : PF_OUT, encif, &m) != PF_PASS) { 2856 m_freem(m); 2857 return EACCES; 2858 } 2859 if (m == NULL) 2860 return 0; 2861 /* 2862 * PF_TAG_REROUTE handling or not... 2863 * Packet is entering IPsec so the routing is 2864 * already overruled by the IPsec policy. 2865 * Until now the change was not reconsidered. 2866 * What's the behaviour? 2867 */ 2868 in6_proto_cksum_out(m, encif); 2869 #endif 2870 2871 /* Check if we are allowed to fragment */ 2872 ip6 = mtod(m, struct ip6_hdr *); 2873 dst = ip6->ip6_dst; 2874 ifidx = m->m_pkthdr.ph_ifidx; 2875 rtableid = m->m_pkthdr.ph_rtableid; 2876 if (ip_mtudisc && tdb->tdb_mtu && 2877 sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) > tdb->tdb_mtu && 2878 tdb->tdb_mtutimeout > gettime()) { 2879 int transportmode; 2880 2881 transportmode = (tdb->tdb_dst.sa.sa_family == AF_INET6) && 2882 (IN6_ARE_ADDR_EQUAL(&tdb->tdb_dst.sin6.sin6_addr, &dst)); 2883 error = ip6_output_ipsec_pmtu_update(tdb, ro, &dst, ifidx, 2884 rtableid, transportmode); 2885 if (error) { 2886 ipsecstat_inc(ipsec_odrops); 2887 tdbstat_inc(tdb, tdb_odrops); 2888 m_freem(m); 2889 return error; 2890 } 2891 ipsec_adjust_mtu(m, tdb->tdb_mtu); 2892 m_freem(m); 2893 return EMSGSIZE; 2894 } 2895 /* propagate don't fragment for v6-over-v6 */ 2896 if (ip_mtudisc) 2897 SET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT); 2898 2899 /* 2900 * Clear these -- they'll be set in the recursive invocation 2901 * as needed. 2902 */ 2903 m->m_flags &= ~(M_BCAST | M_MCAST); 2904 2905 /* Callee frees mbuf */ 2906 KERNEL_LOCK(); 2907 error = ipsp_process_packet(m, tdb, AF_INET6, tunalready); 2908 KERNEL_UNLOCK(); 2909 if (error) { 2910 ipsecstat_inc(ipsec_odrops); 2911 tdbstat_inc(tdb, tdb_odrops); 2912 } 2913 if (ip_mtudisc && error == EMSGSIZE) 2914 ip6_output_ipsec_pmtu_update(tdb, ro, &dst, ifidx, rtableid, 0); 2915 return error; 2916 } 2917 #endif /* IPSEC */ 2918