1 /* $OpenBSD: ip6_output.c,v 1.256 2021/03/10 10:21:49 jsg 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 #include <netinet6/ip6protosw.h> 98 99 #include <crypto/idgen.h> 100 101 #if NPF > 0 102 #include <net/pfvar.h> 103 #endif 104 105 #ifdef IPSEC 106 #include <netinet/ip_ipsp.h> 107 #include <netinet/ip_ah.h> 108 #include <netinet/ip_esp.h> 109 110 #ifdef ENCDEBUG 111 #define DPRINTF(x) do { if (encdebug) printf x ; } while (0) 112 #else 113 #define DPRINTF(x) 114 #endif 115 #endif /* IPSEC */ 116 117 struct ip6_exthdrs { 118 struct mbuf *ip6e_ip6; 119 struct mbuf *ip6e_hbh; 120 struct mbuf *ip6e_dest1; 121 struct mbuf *ip6e_rthdr; 122 struct mbuf *ip6e_dest2; 123 }; 124 125 int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, int, int); 126 int ip6_getpcbopt(struct ip6_pktopts *, int, struct mbuf *); 127 int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, int, int, int); 128 int ip6_setmoptions(int, struct ip6_moptions **, struct mbuf *, unsigned int); 129 int ip6_getmoptions(int, struct ip6_moptions *, struct mbuf *); 130 int ip6_copyexthdr(struct mbuf **, caddr_t, int); 131 int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int, 132 struct ip6_frag **); 133 int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t); 134 int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *); 135 int ip6_getpmtu(struct rtentry *, struct ifnet *, u_long *); 136 int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *); 137 static __inline u_int16_t __attribute__((__unused__)) 138 in6_cksum_phdr(const struct in6_addr *, const struct in6_addr *, 139 u_int32_t, u_int32_t); 140 void in6_delayed_cksum(struct mbuf *, u_int8_t); 141 142 /* Context for non-repeating IDs */ 143 struct idgen32_ctx ip6_id_ctx; 144 145 /* 146 * IP6 output. The packet in mbuf chain m contains a skeletal IP6 147 * header (with pri, len, nxt, hlim, src, dst). 148 * This function may modify ver and hlim only. 149 * The mbuf chain containing the packet will be freed. 150 * The mbuf opt, if present, will not be freed. 151 * 152 * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and 153 * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one, 154 * which is rt_mtu. 155 */ 156 int 157 ip6_output(struct mbuf *m, struct ip6_pktopts *opt, struct route_in6 *ro, 158 int flags, struct ip6_moptions *im6o, struct inpcb *inp) 159 { 160 struct ip6_hdr *ip6; 161 struct ifnet *ifp = NULL; 162 struct mbuf_list fml; 163 int hlen, tlen; 164 struct route_in6 ip6route; 165 struct rtentry *rt = NULL; 166 struct sockaddr_in6 *dst, dstsock; 167 int error = 0; 168 u_long mtu; 169 int dontfrag; 170 u_int16_t src_scope, dst_scope; 171 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; 172 struct ip6_exthdrs exthdrs; 173 struct in6_addr finaldst; 174 struct route_in6 *ro_pmtu = NULL; 175 int hdrsplit = 0; 176 u_int8_t sproto = 0; 177 u_char nextproto; 178 #ifdef IPSEC 179 struct tdb *tdb = NULL; 180 #endif /* IPSEC */ 181 182 #ifdef IPSEC 183 if (inp && (inp->inp_flags & INP_IPV6) == 0) 184 panic("%s: IPv4 pcb is passed", __func__); 185 #endif /* IPSEC */ 186 187 ip6 = mtod(m, struct ip6_hdr *); 188 finaldst = ip6->ip6_dst; 189 190 #define MAKE_EXTHDR(hp, mp) \ 191 do { \ 192 if (hp) { \ 193 struct ip6_ext *eh = (struct ip6_ext *)(hp); \ 194 error = ip6_copyexthdr((mp), (caddr_t)(hp), \ 195 ((eh)->ip6e_len + 1) << 3); \ 196 if (error) \ 197 goto freehdrs; \ 198 } \ 199 } while (0) 200 201 bzero(&exthdrs, sizeof(exthdrs)); 202 203 if (opt) { 204 /* Hop-by-Hop options header */ 205 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh); 206 /* Destination options header(1st part) */ 207 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1); 208 /* Routing header */ 209 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr); 210 /* Destination options header(2nd part) */ 211 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2); 212 } 213 214 #ifdef IPSEC 215 if (ipsec_in_use || inp) { 216 tdb = ip6_output_ipsec_lookup(m, &error, inp); 217 if (error != 0) { 218 /* 219 * -EINVAL is used to indicate that the packet should 220 * be silently dropped, typically because we've asked 221 * key management for an SA. 222 */ 223 if (error == -EINVAL) /* Should silently drop packet */ 224 error = 0; 225 226 goto freehdrs; 227 } 228 } 229 #endif /* IPSEC */ 230 231 /* 232 * Calculate the total length of the extension header chain. 233 * Keep the length of the unfragmentable part for fragmentation. 234 */ 235 optlen = 0; 236 if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len; 237 if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len; 238 if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len; 239 unfragpartlen = optlen + sizeof(struct ip6_hdr); 240 /* NOTE: we don't add AH/ESP length here. do that later. */ 241 if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len; 242 243 /* 244 * If we need IPsec, or there is at least one extension header, 245 * separate IP6 header from the payload. 246 */ 247 if ((sproto || optlen) && !hdrsplit) { 248 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 249 m = NULL; 250 goto freehdrs; 251 } 252 m = exthdrs.ip6e_ip6; 253 hdrsplit++; 254 } 255 256 /* adjust pointer */ 257 ip6 = mtod(m, struct ip6_hdr *); 258 259 /* adjust mbuf packet header length */ 260 m->m_pkthdr.len += optlen; 261 plen = m->m_pkthdr.len - sizeof(*ip6); 262 263 /* If this is a jumbo payload, insert a jumbo payload option. */ 264 if (plen > IPV6_MAXPACKET) { 265 if (!hdrsplit) { 266 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 267 m = NULL; 268 goto freehdrs; 269 } 270 m = exthdrs.ip6e_ip6; 271 hdrsplit++; 272 } 273 /* adjust pointer */ 274 ip6 = mtod(m, struct ip6_hdr *); 275 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) 276 goto freehdrs; 277 ip6->ip6_plen = 0; 278 } else 279 ip6->ip6_plen = htons(plen); 280 281 /* 282 * Concatenate headers and fill in next header fields. 283 * Here we have, on "m" 284 * IPv6 payload 285 * and we insert headers accordingly. Finally, we should be getting: 286 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 287 * 288 * during the header composing process, "m" points to IPv6 header. 289 * "mprev" points to an extension header prior to esp. 290 */ 291 { 292 u_char *nexthdrp = &ip6->ip6_nxt; 293 struct mbuf *mprev = m; 294 295 /* 296 * we treat dest2 specially. this makes IPsec processing 297 * much easier. the goal here is to make mprev point the 298 * mbuf prior to dest2. 299 * 300 * result: IPv6 dest2 payload 301 * m and mprev will point to IPv6 header. 302 */ 303 if (exthdrs.ip6e_dest2) { 304 if (!hdrsplit) 305 panic("%s: assumption failed: hdr not split", 306 __func__); 307 exthdrs.ip6e_dest2->m_next = m->m_next; 308 m->m_next = exthdrs.ip6e_dest2; 309 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; 310 ip6->ip6_nxt = IPPROTO_DSTOPTS; 311 } 312 313 #define MAKE_CHAIN(m, mp, p, i)\ 314 do {\ 315 if (m) {\ 316 if (!hdrsplit) \ 317 panic("assumption failed: hdr not split"); \ 318 *mtod((m), u_char *) = *(p);\ 319 *(p) = (i);\ 320 p = mtod((m), u_char *);\ 321 (m)->m_next = (mp)->m_next;\ 322 (mp)->m_next = (m);\ 323 (mp) = (m);\ 324 }\ 325 } while (0) 326 /* 327 * result: IPv6 hbh dest1 rthdr dest2 payload 328 * m will point to IPv6 header. mprev will point to the 329 * extension header prior to dest2 (rthdr in the above case). 330 */ 331 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); 332 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, 333 IPPROTO_DSTOPTS); 334 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, 335 IPPROTO_ROUTING); 336 } 337 338 /* 339 * If there is a routing header, replace the destination address field 340 * with the first hop of the routing header. 341 */ 342 if (exthdrs.ip6e_rthdr) { 343 struct ip6_rthdr *rh; 344 struct ip6_rthdr0 *rh0; 345 struct in6_addr *addr; 346 347 rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr, 348 struct ip6_rthdr *)); 349 switch (rh->ip6r_type) { 350 case IPV6_RTHDR_TYPE_0: 351 rh0 = (struct ip6_rthdr0 *)rh; 352 addr = (struct in6_addr *)(rh0 + 1); 353 ip6->ip6_dst = addr[0]; 354 bcopy(&addr[1], &addr[0], 355 sizeof(struct in6_addr) * (rh0->ip6r0_segleft - 1)); 356 addr[rh0->ip6r0_segleft - 1] = finaldst; 357 break; 358 default: /* is it possible? */ 359 error = EINVAL; 360 goto bad; 361 } 362 } 363 364 /* Source address validation */ 365 if (!(flags & IPV6_UNSPECSRC) && 366 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) { 367 /* 368 * XXX: we can probably assume validation in the caller, but 369 * we explicitly check the address here for safety. 370 */ 371 error = EOPNOTSUPP; 372 ip6stat_inc(ip6s_badscope); 373 goto bad; 374 } 375 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { 376 error = EOPNOTSUPP; 377 ip6stat_inc(ip6s_badscope); 378 goto bad; 379 } 380 381 ip6stat_inc(ip6s_localout); 382 383 /* 384 * Route packet. 385 */ 386 #if NPF > 0 387 reroute: 388 #endif 389 390 /* initialize cached route */ 391 if (ro == NULL) { 392 ro = &ip6route; 393 bzero((caddr_t)ro, sizeof(*ro)); 394 } 395 ro_pmtu = ro; 396 if (opt && opt->ip6po_rthdr) 397 ro = &opt->ip6po_route; 398 dst = &ro->ro_dst; 399 400 /* 401 * if specified, try to fill in the traffic class field. 402 * do not override if a non-zero value is already set. 403 * we check the diffserv field and the ecn field separately. 404 */ 405 if (opt && opt->ip6po_tclass >= 0) { 406 int mask = 0; 407 408 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0) 409 mask |= 0xfc; 410 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0) 411 mask |= 0x03; 412 if (mask != 0) 413 ip6->ip6_flow |= 414 htonl((opt->ip6po_tclass & mask) << 20); 415 } 416 417 /* fill in or override the hop limit field, if necessary. */ 418 if (opt && opt->ip6po_hlim != -1) 419 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 420 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 421 if (im6o != NULL) 422 ip6->ip6_hlim = im6o->im6o_hlim; 423 else 424 ip6->ip6_hlim = ip6_defmcasthlim; 425 } 426 427 #ifdef IPSEC 428 if (tdb) { 429 /* 430 * XXX what should we do if ip6_hlim == 0 and the 431 * packet gets tunneled? 432 */ 433 /* 434 * if we are source-routing, do not attempt to tunnel the 435 * packet just because ip6_dst is different from what tdb has. 436 * XXX 437 */ 438 error = ip6_output_ipsec_send(tdb, m, ro, 439 exthdrs.ip6e_rthdr ? 1 : 0, 0); 440 goto done; 441 } 442 #endif /* IPSEC */ 443 444 bzero(&dstsock, sizeof(dstsock)); 445 dstsock.sin6_family = AF_INET6; 446 dstsock.sin6_addr = ip6->ip6_dst; 447 dstsock.sin6_len = sizeof(dstsock); 448 ro->ro_tableid = m->m_pkthdr.ph_rtableid; 449 450 if (IN6_IS_ADDR_MULTICAST(&dstsock.sin6_addr)) { 451 struct in6_pktinfo *pi = NULL; 452 453 /* 454 * If the caller specify the outgoing interface 455 * explicitly, use it. 456 */ 457 if (opt != NULL && (pi = opt->ip6po_pktinfo) != NULL) 458 ifp = if_get(pi->ipi6_ifindex); 459 460 if (ifp == NULL && im6o != NULL) 461 ifp = if_get(im6o->im6o_ifidx); 462 } 463 464 if (ifp == NULL) { 465 rt = in6_selectroute(&dstsock, opt, ro, ro->ro_tableid); 466 if (rt == NULL) { 467 ip6stat_inc(ip6s_noroute); 468 error = EHOSTUNREACH; 469 goto bad; 470 } 471 if (ISSET(rt->rt_flags, RTF_LOCAL)) 472 ifp = if_get(rtable_loindex(m->m_pkthdr.ph_rtableid)); 473 else 474 ifp = if_get(rt->rt_ifidx); 475 /* 476 * We aren't using rtisvalid() here because the UP/DOWN state 477 * machine is broken with some Ethernet drivers like em(4). 478 * As a result we might try to use an invalid cached route 479 * entry while an interface is being detached. 480 */ 481 if (ifp == NULL) { 482 ip6stat_inc(ip6s_noroute); 483 error = EHOSTUNREACH; 484 goto bad; 485 } 486 } else { 487 *dst = dstsock; 488 } 489 490 if (rt && (rt->rt_flags & RTF_GATEWAY) && 491 !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 492 dst = satosin6(rt->rt_gateway); 493 494 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 495 /* Unicast */ 496 497 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ 498 } else { 499 /* Multicast */ 500 501 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; 502 503 /* 504 * Confirm that the outgoing interface supports multicast. 505 */ 506 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 507 ip6stat_inc(ip6s_noroute); 508 error = ENETUNREACH; 509 goto bad; 510 } 511 512 if ((im6o == NULL || im6o->im6o_loop) && 513 in6_hasmulti(&ip6->ip6_dst, ifp)) { 514 /* 515 * If we belong to the destination multicast group 516 * on the outgoing interface, and the caller did not 517 * forbid loopback, loop back a copy. 518 * Can't defer TCP/UDP checksumming, do the 519 * computation now. 520 */ 521 in6_proto_cksum_out(m, NULL); 522 ip6_mloopback(ifp, m, dst); 523 } 524 #ifdef MROUTING 525 else { 526 /* 527 * If we are acting as a multicast router, perform 528 * multicast forwarding as if the packet had just 529 * arrived on the interface to which we are about 530 * to send. The multicast forwarding function 531 * recursively calls this function, using the 532 * IPV6_FORWARDING flag to prevent infinite recursion. 533 * 534 * Multicasts that are looped back by ip6_mloopback(), 535 * above, will be forwarded by the ip6_input() routine, 536 * if necessary. 537 */ 538 if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain] && 539 (flags & IPV6_FORWARDING) == 0) { 540 if (ip6_mforward(ip6, ifp, m) != 0) { 541 m_freem(m); 542 goto done; 543 } 544 } 545 } 546 #endif 547 /* 548 * Multicasts with a hoplimit of zero may be looped back, 549 * above, but must not be transmitted on a network. 550 * Also, multicasts addressed to the loopback interface 551 * are not sent -- the above call to ip6_mloopback() will 552 * loop back a copy if this host actually belongs to the 553 * destination group on the loopback interface. 554 */ 555 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) || 556 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) { 557 m_freem(m); 558 goto done; 559 } 560 } 561 562 /* 563 * If this packet is going through a loopback interface we won't 564 * be able to restore its scope ID using the interface index. 565 */ 566 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { 567 if (ifp->if_flags & IFF_LOOPBACK) 568 src_scope = ip6->ip6_src.s6_addr16[1]; 569 ip6->ip6_src.s6_addr16[1] = 0; 570 } 571 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { 572 if (ifp->if_flags & IFF_LOOPBACK) 573 dst_scope = ip6->ip6_dst.s6_addr16[1]; 574 ip6->ip6_dst.s6_addr16[1] = 0; 575 } 576 577 /* Determine path MTU. */ 578 if ((error = ip6_getpmtu(ro_pmtu->ro_rt, ifp, &mtu)) != 0) 579 goto bad; 580 581 /* 582 * The caller of this function may specify to use the minimum MTU 583 * in some cases. 584 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU 585 * setting. The logic is a bit complicated; by default, unicast 586 * packets will follow path MTU while multicast packets will be sent at 587 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets 588 * including unicast ones will be sent at the minimum MTU. Multicast 589 * packets will always be sent at the minimum MTU unless 590 * IP6PO_MINMTU_DISABLE is explicitly specified. 591 * See RFC 3542 for more details. 592 */ 593 if (mtu > IPV6_MMTU) { 594 if ((flags & IPV6_MINMTU)) 595 mtu = IPV6_MMTU; 596 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL) 597 mtu = IPV6_MMTU; 598 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && (opt == NULL || 599 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) { 600 mtu = IPV6_MMTU; 601 } 602 } 603 604 /* 605 * If the outgoing packet contains a hop-by-hop options header, 606 * it must be examined and processed even by the source node. 607 * (RFC 2460, section 4.) 608 */ 609 if (exthdrs.ip6e_hbh) { 610 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *); 611 u_int32_t rtalert; /* returned value is ignored */ 612 u_int32_t plen = 0; /* no more than 1 jumbo payload option! */ 613 614 m->m_pkthdr.ph_ifidx = ifp->if_index; 615 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1), 616 ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh), 617 &rtalert, &plen) < 0) { 618 /* m was already freed at this point */ 619 error = EINVAL;/* better error? */ 620 goto done; 621 } 622 m->m_pkthdr.ph_ifidx = 0; 623 } 624 625 #if NPF > 0 626 if (pf_test(AF_INET6, PF_OUT, ifp, &m) != PF_PASS) { 627 error = EACCES; 628 m_freem(m); 629 goto done; 630 } 631 if (m == NULL) 632 goto done; 633 ip6 = mtod(m, struct ip6_hdr *); 634 if ((m->m_pkthdr.pf.flags & (PF_TAG_REROUTE | PF_TAG_GENERATED)) == 635 (PF_TAG_REROUTE | PF_TAG_GENERATED)) { 636 /* already rerun the route lookup, go on */ 637 m->m_pkthdr.pf.flags &= ~(PF_TAG_GENERATED | PF_TAG_REROUTE); 638 } else if (m->m_pkthdr.pf.flags & PF_TAG_REROUTE) { 639 /* tag as generated to skip over pf_test on rerun */ 640 m->m_pkthdr.pf.flags |= PF_TAG_GENERATED; 641 finaldst = ip6->ip6_dst; 642 ro = NULL; 643 if_put(ifp); /* drop reference since destination changed */ 644 ifp = NULL; 645 goto reroute; 646 } 647 #endif 648 649 /* 650 * If the packet is not going on the wire it can be destinated 651 * to any local address. In this case do not clear its scopes 652 * to let ip6_input() find a matching local route. 653 */ 654 if (ifp->if_flags & IFF_LOOPBACK) { 655 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 656 ip6->ip6_src.s6_addr16[1] = src_scope; 657 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 658 ip6->ip6_dst.s6_addr16[1] = dst_scope; 659 } 660 661 in6_proto_cksum_out(m, ifp); 662 663 /* 664 * Send the packet to the outgoing interface. 665 * If necessary, do IPv6 fragmentation before sending. 666 * 667 * the logic here is rather complex: 668 * 1: normal case (dontfrag == 0) 669 * 1-a: send as is if tlen <= path mtu 670 * 1-b: fragment if tlen > path mtu 671 * 672 * 2: if user asks us not to fragment (dontfrag == 1) 673 * 2-a: send as is if tlen <= interface mtu 674 * 2-b: error if tlen > interface mtu 675 */ 676 tlen = m->m_pkthdr.len; 677 678 if (ISSET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT)) { 679 CLR(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT); 680 dontfrag = 1; 681 } else if (opt && ISSET(opt->ip6po_flags, IP6PO_DONTFRAG)) 682 dontfrag = 1; 683 else 684 dontfrag = 0; 685 if (dontfrag && tlen > ifp->if_mtu) { /* case 2-b */ 686 #ifdef IPSEC 687 if (ip_mtudisc) 688 ipsec_adjust_mtu(m, mtu); 689 #endif 690 error = EMSGSIZE; 691 goto bad; 692 } 693 694 /* 695 * transmit packet without fragmentation 696 */ 697 if (dontfrag || (tlen <= mtu)) { /* case 1-a and 2-a */ 698 error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt); 699 goto done; 700 } 701 702 /* 703 * try to fragment the packet. case 1-b 704 */ 705 if (mtu < IPV6_MMTU) { 706 /* path MTU cannot be less than IPV6_MMTU */ 707 error = EMSGSIZE; 708 goto bad; 709 } else if (ip6->ip6_plen == 0) { 710 /* jumbo payload cannot be fragmented */ 711 error = EMSGSIZE; 712 goto bad; 713 } 714 715 /* 716 * Too large for the destination or interface; 717 * fragment if possible. 718 * Must be able to put at least 8 bytes per fragment. 719 */ 720 hlen = unfragpartlen; 721 if (mtu > IPV6_MAXPACKET) 722 mtu = IPV6_MAXPACKET; 723 724 /* 725 * Change the next header field of the last header in the 726 * unfragmentable part. 727 */ 728 if (exthdrs.ip6e_rthdr) { 729 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); 730 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; 731 } else if (exthdrs.ip6e_dest1) { 732 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); 733 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; 734 } else if (exthdrs.ip6e_hbh) { 735 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); 736 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; 737 } else { 738 nextproto = ip6->ip6_nxt; 739 ip6->ip6_nxt = IPPROTO_FRAGMENT; 740 } 741 742 error = ip6_fragment(m, &fml, hlen, nextproto, mtu); 743 if (error) 744 goto done; 745 746 while ((m = ml_dequeue(&fml)) != NULL) { 747 error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt); 748 if (error) 749 break; 750 } 751 if (error) 752 ml_purge(&fml); 753 else 754 ip6stat_inc(ip6s_fragmented); 755 756 done: 757 if_put(ifp); 758 if (ro == &ip6route && ro->ro_rt) { 759 rtfree(ro->ro_rt); 760 } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) { 761 rtfree(ro_pmtu->ro_rt); 762 } 763 return (error); 764 765 freehdrs: 766 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */ 767 m_freem(exthdrs.ip6e_dest1); 768 m_freem(exthdrs.ip6e_rthdr); 769 m_freem(exthdrs.ip6e_dest2); 770 /* FALLTHROUGH */ 771 bad: 772 m_freem(m); 773 goto done; 774 } 775 776 int 777 ip6_fragment(struct mbuf *m0, struct mbuf_list *fml, int hlen, 778 u_char nextproto, u_long mtu) 779 { 780 struct mbuf *m, *m_frgpart; 781 struct ip6_hdr *mhip6; 782 struct ip6_frag *ip6f; 783 u_int32_t id; 784 int tlen, len, off; 785 int error; 786 787 ml_init(fml); 788 789 tlen = m0->m_pkthdr.len; 790 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; 791 if (len < 8) { 792 error = EMSGSIZE; 793 goto bad; 794 } 795 796 id = htonl(ip6_randomid()); 797 798 /* 799 * Loop through length of segment after first fragment, 800 * make new header and copy data of each part and link onto chain. 801 */ 802 for (off = hlen; off < tlen; off += len) { 803 struct mbuf *mlast; 804 805 MGETHDR(m, M_DONTWAIT, MT_HEADER); 806 if (m == NULL) { 807 error = ENOBUFS; 808 goto bad; 809 } 810 ml_enqueue(fml, m); 811 if ((error = m_dup_pkthdr(m, m0, M_DONTWAIT)) != 0) 812 goto bad; 813 m->m_data += max_linkhdr; 814 mhip6 = mtod(m, struct ip6_hdr *); 815 *mhip6 = *mtod(m0, struct ip6_hdr *); 816 m->m_len = sizeof(*mhip6); 817 if ((error = ip6_insertfraghdr(m0, m, hlen, &ip6f)) != 0) 818 goto bad; 819 ip6f->ip6f_offlg = htons((u_int16_t)((off - hlen) & ~7)); 820 if (off + len >= tlen) 821 len = tlen - off; 822 else 823 ip6f->ip6f_offlg |= IP6F_MORE_FRAG; 824 mhip6->ip6_plen = htons((u_int16_t)(len + hlen + 825 sizeof(*ip6f) - sizeof(struct ip6_hdr))); 826 if ((m_frgpart = m_copym(m0, off, len, M_DONTWAIT)) == NULL) { 827 error = ENOBUFS; 828 goto bad; 829 } 830 for (mlast = m; mlast->m_next; mlast = mlast->m_next) 831 ; 832 mlast->m_next = m_frgpart; 833 m->m_pkthdr.len = len + hlen + sizeof(*ip6f); 834 ip6f->ip6f_reserved = 0; 835 ip6f->ip6f_ident = id; 836 ip6f->ip6f_nxt = nextproto; 837 } 838 839 ip6stat_add(ip6s_ofragments, ml_len(fml)); 840 m_freem(m0); 841 return (0); 842 843 bad: 844 ip6stat_inc(ip6s_odropped); 845 ml_purge(fml); 846 m_freem(m0); 847 return (error); 848 } 849 850 int 851 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen) 852 { 853 struct mbuf *m; 854 855 if (hlen > MCLBYTES) 856 return (ENOBUFS); /* XXX */ 857 858 MGET(m, M_DONTWAIT, MT_DATA); 859 if (!m) 860 return (ENOBUFS); 861 862 if (hlen > MLEN) { 863 MCLGET(m, M_DONTWAIT); 864 if ((m->m_flags & M_EXT) == 0) { 865 m_free(m); 866 return (ENOBUFS); 867 } 868 } 869 m->m_len = hlen; 870 if (hdr) 871 memcpy(mtod(m, caddr_t), hdr, hlen); 872 873 *mp = m; 874 return (0); 875 } 876 877 /* 878 * Insert jumbo payload option. 879 */ 880 int 881 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen) 882 { 883 struct mbuf *mopt; 884 u_int8_t *optbuf; 885 u_int32_t v; 886 887 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */ 888 889 /* 890 * If there is no hop-by-hop options header, allocate new one. 891 * If there is one but it doesn't have enough space to store the 892 * jumbo payload option, allocate a cluster to store the whole options. 893 * Otherwise, use it to store the options. 894 */ 895 if (exthdrs->ip6e_hbh == 0) { 896 MGET(mopt, M_DONTWAIT, MT_DATA); 897 if (mopt == NULL) 898 return (ENOBUFS); 899 mopt->m_len = JUMBOOPTLEN; 900 optbuf = mtod(mopt, u_int8_t *); 901 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */ 902 exthdrs->ip6e_hbh = mopt; 903 } else { 904 struct ip6_hbh *hbh; 905 906 mopt = exthdrs->ip6e_hbh; 907 if (m_trailingspace(mopt) < JUMBOOPTLEN) { 908 /* 909 * XXX assumption: 910 * - exthdrs->ip6e_hbh is not referenced from places 911 * other than exthdrs. 912 * - exthdrs->ip6e_hbh is not an mbuf chain. 913 */ 914 int oldoptlen = mopt->m_len; 915 struct mbuf *n; 916 917 /* 918 * XXX: give up if the whole (new) hbh header does 919 * not fit even in an mbuf cluster. 920 */ 921 if (oldoptlen + JUMBOOPTLEN > MCLBYTES) 922 return (ENOBUFS); 923 924 /* 925 * As a consequence, we must always prepare a cluster 926 * at this point. 927 */ 928 MGET(n, M_DONTWAIT, MT_DATA); 929 if (n) { 930 MCLGET(n, M_DONTWAIT); 931 if ((n->m_flags & M_EXT) == 0) { 932 m_freem(n); 933 n = NULL; 934 } 935 } 936 if (!n) 937 return (ENOBUFS); 938 n->m_len = oldoptlen + JUMBOOPTLEN; 939 memcpy(mtod(n, caddr_t), mtod(mopt, caddr_t), 940 oldoptlen); 941 optbuf = mtod(n, u_int8_t *) + oldoptlen; 942 m_freem(mopt); 943 mopt = exthdrs->ip6e_hbh = n; 944 } else { 945 optbuf = mtod(mopt, u_int8_t *) + mopt->m_len; 946 mopt->m_len += JUMBOOPTLEN; 947 } 948 optbuf[0] = IP6OPT_PADN; 949 optbuf[1] = 0; 950 951 /* 952 * Adjust the header length according to the pad and 953 * the jumbo payload option. 954 */ 955 hbh = mtod(mopt, struct ip6_hbh *); 956 hbh->ip6h_len += (JUMBOOPTLEN >> 3); 957 } 958 959 /* fill in the option. */ 960 optbuf[2] = IP6OPT_JUMBO; 961 optbuf[3] = 4; 962 v = (u_int32_t)htonl(plen + JUMBOOPTLEN); 963 memcpy(&optbuf[4], &v, sizeof(u_int32_t)); 964 965 /* finally, adjust the packet header length */ 966 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN; 967 968 return (0); 969 #undef JUMBOOPTLEN 970 } 971 972 /* 973 * Insert fragment header and copy unfragmentable header portions. 974 */ 975 int 976 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen, 977 struct ip6_frag **frghdrp) 978 { 979 struct mbuf *n, *mlast; 980 981 if (hlen > sizeof(struct ip6_hdr)) { 982 n = m_copym(m0, sizeof(struct ip6_hdr), 983 hlen - sizeof(struct ip6_hdr), M_DONTWAIT); 984 if (n == NULL) 985 return (ENOBUFS); 986 m->m_next = n; 987 } else 988 n = m; 989 990 /* Search for the last mbuf of unfragmentable part. */ 991 for (mlast = n; mlast->m_next; mlast = mlast->m_next) 992 ; 993 994 if ((mlast->m_flags & M_EXT) == 0 && 995 m_trailingspace(mlast) >= sizeof(struct ip6_frag)) { 996 /* use the trailing space of the last mbuf for fragment hdr */ 997 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) + 998 mlast->m_len); 999 mlast->m_len += sizeof(struct ip6_frag); 1000 m->m_pkthdr.len += sizeof(struct ip6_frag); 1001 } else { 1002 /* allocate a new mbuf for the fragment header */ 1003 struct mbuf *mfrg; 1004 1005 MGET(mfrg, M_DONTWAIT, MT_DATA); 1006 if (mfrg == NULL) 1007 return (ENOBUFS); 1008 mfrg->m_len = sizeof(struct ip6_frag); 1009 *frghdrp = mtod(mfrg, struct ip6_frag *); 1010 mlast->m_next = mfrg; 1011 } 1012 1013 return (0); 1014 } 1015 1016 int 1017 ip6_getpmtu(struct rtentry *rt, struct ifnet *ifp, u_long *mtup) 1018 { 1019 u_int32_t mtu = 0; 1020 int error = 0; 1021 1022 if (rt != NULL) { 1023 mtu = rt->rt_mtu; 1024 if (mtu == 0) 1025 mtu = ifp->if_mtu; 1026 else if (mtu < IPV6_MMTU) { 1027 /* RFC8021 IPv6 Atomic Fragments Considered Harmful */ 1028 mtu = IPV6_MMTU; 1029 } else if (mtu > ifp->if_mtu) { 1030 /* 1031 * The MTU on the route is larger than the MTU on 1032 * the interface! This shouldn't happen, unless the 1033 * MTU of the interface has been changed after the 1034 * interface was brought up. Change the MTU in the 1035 * route to match the interface MTU (as long as the 1036 * field isn't locked). 1037 */ 1038 mtu = ifp->if_mtu; 1039 if (!(rt->rt_locks & RTV_MTU)) 1040 rt->rt_mtu = mtu; 1041 } 1042 } else { 1043 mtu = ifp->if_mtu; 1044 } 1045 1046 *mtup = mtu; 1047 return (error); 1048 } 1049 1050 /* 1051 * IP6 socket option processing. 1052 */ 1053 int 1054 ip6_ctloutput(int op, struct socket *so, int level, int optname, 1055 struct mbuf *m) 1056 { 1057 int privileged, optdatalen, uproto; 1058 void *optdata; 1059 struct inpcb *inp = sotoinpcb(so); 1060 int error, optval; 1061 struct proc *p = curproc; /* For IPsec and rdomain */ 1062 u_int rtid = 0; 1063 1064 error = optval = 0; 1065 1066 privileged = (inp->inp_socket->so_state & SS_PRIV); 1067 uproto = (int)so->so_proto->pr_protocol; 1068 1069 if (level != IPPROTO_IPV6) 1070 return (EINVAL); 1071 1072 switch (op) { 1073 case PRCO_SETOPT: 1074 switch (optname) { 1075 /* 1076 * Use of some Hop-by-Hop options or some 1077 * Destination options, might require special 1078 * privilege. That is, normal applications 1079 * (without special privilege) might be forbidden 1080 * from setting certain options in outgoing packets, 1081 * and might never see certain options in received 1082 * packets. [RFC 2292 Section 6] 1083 * KAME specific note: 1084 * KAME prevents non-privileged users from sending or 1085 * receiving ANY hbh/dst options in order to avoid 1086 * overhead of parsing options in the kernel. 1087 */ 1088 case IPV6_RECVHOPOPTS: 1089 case IPV6_RECVDSTOPTS: 1090 if (!privileged) { 1091 error = EPERM; 1092 break; 1093 } 1094 /* FALLTHROUGH */ 1095 case IPV6_UNICAST_HOPS: 1096 case IPV6_MINHOPCOUNT: 1097 case IPV6_HOPLIMIT: 1098 1099 case IPV6_RECVPKTINFO: 1100 case IPV6_RECVHOPLIMIT: 1101 case IPV6_RECVRTHDR: 1102 case IPV6_RECVPATHMTU: 1103 case IPV6_RECVTCLASS: 1104 case IPV6_V6ONLY: 1105 case IPV6_AUTOFLOWLABEL: 1106 case IPV6_RECVDSTPORT: 1107 if (m == NULL || m->m_len != sizeof(int)) { 1108 error = EINVAL; 1109 break; 1110 } 1111 optval = *mtod(m, int *); 1112 switch (optname) { 1113 1114 case IPV6_UNICAST_HOPS: 1115 if (optval < -1 || optval >= 256) 1116 error = EINVAL; 1117 else { 1118 /* -1 = kernel default */ 1119 inp->inp_hops = optval; 1120 } 1121 break; 1122 1123 case IPV6_MINHOPCOUNT: 1124 if (optval < 0 || optval > 255) 1125 error = EINVAL; 1126 else 1127 inp->inp_ip6_minhlim = optval; 1128 break; 1129 1130 #define OPTSET(bit) \ 1131 do { \ 1132 if (optval) \ 1133 inp->inp_flags |= (bit); \ 1134 else \ 1135 inp->inp_flags &= ~(bit); \ 1136 } while (/*CONSTCOND*/ 0) 1137 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0) 1138 1139 case IPV6_RECVPKTINFO: 1140 OPTSET(IN6P_PKTINFO); 1141 break; 1142 1143 case IPV6_HOPLIMIT: 1144 { 1145 struct ip6_pktopts **optp; 1146 1147 optp = &inp->inp_outputopts6; 1148 error = ip6_pcbopt(IPV6_HOPLIMIT, 1149 (u_char *)&optval, sizeof(optval), optp, 1150 privileged, uproto); 1151 break; 1152 } 1153 1154 case IPV6_RECVHOPLIMIT: 1155 OPTSET(IN6P_HOPLIMIT); 1156 break; 1157 1158 case IPV6_RECVHOPOPTS: 1159 OPTSET(IN6P_HOPOPTS); 1160 break; 1161 1162 case IPV6_RECVDSTOPTS: 1163 OPTSET(IN6P_DSTOPTS); 1164 break; 1165 1166 case IPV6_RECVRTHDR: 1167 OPTSET(IN6P_RTHDR); 1168 break; 1169 1170 case IPV6_RECVPATHMTU: 1171 /* 1172 * We ignore this option for TCP 1173 * sockets. 1174 * (RFC3542 leaves this case 1175 * unspecified.) 1176 */ 1177 if (uproto != IPPROTO_TCP) 1178 OPTSET(IN6P_MTU); 1179 break; 1180 1181 case IPV6_V6ONLY: 1182 /* 1183 * make setsockopt(IPV6_V6ONLY) 1184 * available only prior to bind(2). 1185 * see ipng mailing list, Jun 22 2001. 1186 */ 1187 if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED( 1188 &inp->inp_laddr6)) { 1189 error = EINVAL; 1190 break; 1191 } 1192 /* No support for IPv4-mapped addresses. */ 1193 if (!optval) 1194 error = EINVAL; 1195 else 1196 error = 0; 1197 break; 1198 case IPV6_RECVTCLASS: 1199 OPTSET(IN6P_TCLASS); 1200 break; 1201 case IPV6_AUTOFLOWLABEL: 1202 OPTSET(IN6P_AUTOFLOWLABEL); 1203 break; 1204 1205 case IPV6_RECVDSTPORT: 1206 OPTSET(IN6P_RECVDSTPORT); 1207 break; 1208 } 1209 break; 1210 1211 case IPV6_TCLASS: 1212 case IPV6_DONTFRAG: 1213 case IPV6_USE_MIN_MTU: 1214 if (m == NULL || m->m_len != sizeof(optval)) { 1215 error = EINVAL; 1216 break; 1217 } 1218 optval = *mtod(m, int *); 1219 { 1220 struct ip6_pktopts **optp; 1221 optp = &inp->inp_outputopts6; 1222 error = ip6_pcbopt(optname, (u_char *)&optval, 1223 sizeof(optval), optp, privileged, uproto); 1224 break; 1225 } 1226 1227 case IPV6_PKTINFO: 1228 case IPV6_HOPOPTS: 1229 case IPV6_RTHDR: 1230 case IPV6_DSTOPTS: 1231 case IPV6_RTHDRDSTOPTS: 1232 { 1233 /* new advanced API (RFC3542) */ 1234 u_char *optbuf; 1235 int optbuflen; 1236 struct ip6_pktopts **optp; 1237 1238 if (m && m->m_next) { 1239 error = EINVAL; /* XXX */ 1240 break; 1241 } 1242 if (m) { 1243 optbuf = mtod(m, u_char *); 1244 optbuflen = m->m_len; 1245 } else { 1246 optbuf = NULL; 1247 optbuflen = 0; 1248 } 1249 optp = &inp->inp_outputopts6; 1250 error = ip6_pcbopt(optname, optbuf, optbuflen, optp, 1251 privileged, uproto); 1252 break; 1253 } 1254 #undef OPTSET 1255 1256 case IPV6_MULTICAST_IF: 1257 case IPV6_MULTICAST_HOPS: 1258 case IPV6_MULTICAST_LOOP: 1259 case IPV6_JOIN_GROUP: 1260 case IPV6_LEAVE_GROUP: 1261 error = ip6_setmoptions(optname, 1262 &inp->inp_moptions6, 1263 m, inp->inp_rtableid); 1264 break; 1265 1266 case IPV6_PORTRANGE: 1267 if (m == NULL || m->m_len != sizeof(int)) { 1268 error = EINVAL; 1269 break; 1270 } 1271 optval = *mtod(m, int *); 1272 1273 switch (optval) { 1274 case IPV6_PORTRANGE_DEFAULT: 1275 inp->inp_flags &= ~(IN6P_LOWPORT); 1276 inp->inp_flags &= ~(IN6P_HIGHPORT); 1277 break; 1278 1279 case IPV6_PORTRANGE_HIGH: 1280 inp->inp_flags &= ~(IN6P_LOWPORT); 1281 inp->inp_flags |= IN6P_HIGHPORT; 1282 break; 1283 1284 case IPV6_PORTRANGE_LOW: 1285 inp->inp_flags &= ~(IN6P_HIGHPORT); 1286 inp->inp_flags |= IN6P_LOWPORT; 1287 break; 1288 1289 default: 1290 error = EINVAL; 1291 break; 1292 } 1293 break; 1294 1295 case IPSEC6_OUTSA: 1296 error = EINVAL; 1297 break; 1298 1299 case IPV6_AUTH_LEVEL: 1300 case IPV6_ESP_TRANS_LEVEL: 1301 case IPV6_ESP_NETWORK_LEVEL: 1302 case IPV6_IPCOMP_LEVEL: 1303 #ifndef IPSEC 1304 error = EINVAL; 1305 #else 1306 if (m == NULL || m->m_len != sizeof(int)) { 1307 error = EINVAL; 1308 break; 1309 } 1310 optval = *mtod(m, int *); 1311 1312 if (optval < IPSEC_LEVEL_BYPASS || 1313 optval > IPSEC_LEVEL_UNIQUE) { 1314 error = EINVAL; 1315 break; 1316 } 1317 1318 switch (optname) { 1319 case IPV6_AUTH_LEVEL: 1320 if (optval < IPSEC_AUTH_LEVEL_DEFAULT && 1321 suser(p)) { 1322 error = EACCES; 1323 break; 1324 } 1325 inp->inp_seclevel[SL_AUTH] = optval; 1326 break; 1327 1328 case IPV6_ESP_TRANS_LEVEL: 1329 if (optval < IPSEC_ESP_TRANS_LEVEL_DEFAULT && 1330 suser(p)) { 1331 error = EACCES; 1332 break; 1333 } 1334 inp->inp_seclevel[SL_ESP_TRANS] = optval; 1335 break; 1336 1337 case IPV6_ESP_NETWORK_LEVEL: 1338 if (optval < IPSEC_ESP_NETWORK_LEVEL_DEFAULT && 1339 suser(p)) { 1340 error = EACCES; 1341 break; 1342 } 1343 inp->inp_seclevel[SL_ESP_NETWORK] = optval; 1344 break; 1345 1346 case IPV6_IPCOMP_LEVEL: 1347 if (optval < IPSEC_IPCOMP_LEVEL_DEFAULT && 1348 suser(p)) { 1349 error = EACCES; 1350 break; 1351 } 1352 inp->inp_seclevel[SL_IPCOMP] = optval; 1353 break; 1354 } 1355 #endif 1356 break; 1357 case SO_RTABLE: 1358 if (m == NULL || m->m_len < sizeof(u_int)) { 1359 error = EINVAL; 1360 break; 1361 } 1362 rtid = *mtod(m, u_int *); 1363 if (inp->inp_rtableid == rtid) 1364 break; 1365 /* needs privileges to switch when already set */ 1366 if (p->p_p->ps_rtableid != rtid && 1367 p->p_p->ps_rtableid != 0 && 1368 (error = suser(p)) != 0) 1369 break; 1370 /* table must exist */ 1371 if (!rtable_exists(rtid)) { 1372 error = EINVAL; 1373 break; 1374 } 1375 if (inp->inp_lport) { 1376 error = EBUSY; 1377 break; 1378 } 1379 inp->inp_rtableid = rtid; 1380 in_pcbrehash(inp); 1381 break; 1382 case IPV6_PIPEX: 1383 if (m != NULL && m->m_len == sizeof(int)) 1384 inp->inp_pipex = *mtod(m, int *); 1385 else 1386 error = EINVAL; 1387 break; 1388 1389 default: 1390 error = ENOPROTOOPT; 1391 break; 1392 } 1393 break; 1394 1395 case PRCO_GETOPT: 1396 switch (optname) { 1397 1398 case IPV6_RECVHOPOPTS: 1399 case IPV6_RECVDSTOPTS: 1400 case IPV6_UNICAST_HOPS: 1401 case IPV6_MINHOPCOUNT: 1402 case IPV6_RECVPKTINFO: 1403 case IPV6_RECVHOPLIMIT: 1404 case IPV6_RECVRTHDR: 1405 case IPV6_RECVPATHMTU: 1406 1407 case IPV6_V6ONLY: 1408 case IPV6_PORTRANGE: 1409 case IPV6_RECVTCLASS: 1410 case IPV6_AUTOFLOWLABEL: 1411 case IPV6_RECVDSTPORT: 1412 switch (optname) { 1413 1414 case IPV6_RECVHOPOPTS: 1415 optval = OPTBIT(IN6P_HOPOPTS); 1416 break; 1417 1418 case IPV6_RECVDSTOPTS: 1419 optval = OPTBIT(IN6P_DSTOPTS); 1420 break; 1421 1422 case IPV6_UNICAST_HOPS: 1423 optval = inp->inp_hops; 1424 break; 1425 1426 case IPV6_MINHOPCOUNT: 1427 optval = inp->inp_ip6_minhlim; 1428 break; 1429 1430 case IPV6_RECVPKTINFO: 1431 optval = OPTBIT(IN6P_PKTINFO); 1432 break; 1433 1434 case IPV6_RECVHOPLIMIT: 1435 optval = OPTBIT(IN6P_HOPLIMIT); 1436 break; 1437 1438 case IPV6_RECVRTHDR: 1439 optval = OPTBIT(IN6P_RTHDR); 1440 break; 1441 1442 case IPV6_RECVPATHMTU: 1443 optval = OPTBIT(IN6P_MTU); 1444 break; 1445 1446 case IPV6_V6ONLY: 1447 optval = 1; 1448 break; 1449 1450 case IPV6_PORTRANGE: 1451 { 1452 int flags; 1453 flags = inp->inp_flags; 1454 if (flags & IN6P_HIGHPORT) 1455 optval = IPV6_PORTRANGE_HIGH; 1456 else if (flags & IN6P_LOWPORT) 1457 optval = IPV6_PORTRANGE_LOW; 1458 else 1459 optval = 0; 1460 break; 1461 } 1462 case IPV6_RECVTCLASS: 1463 optval = OPTBIT(IN6P_TCLASS); 1464 break; 1465 1466 case IPV6_AUTOFLOWLABEL: 1467 optval = OPTBIT(IN6P_AUTOFLOWLABEL); 1468 break; 1469 1470 case IPV6_RECVDSTPORT: 1471 optval = OPTBIT(IN6P_RECVDSTPORT); 1472 break; 1473 } 1474 if (error) 1475 break; 1476 m->m_len = sizeof(int); 1477 *mtod(m, int *) = optval; 1478 break; 1479 1480 case IPV6_PATHMTU: 1481 { 1482 u_long pmtu = 0; 1483 struct ip6_mtuinfo mtuinfo; 1484 struct ifnet *ifp; 1485 struct rtentry *rt; 1486 1487 if (!(so->so_state & SS_ISCONNECTED)) 1488 return (ENOTCONN); 1489 1490 rt = in_pcbrtentry(inp); 1491 if (!rtisvalid(rt)) 1492 return (EHOSTUNREACH); 1493 1494 ifp = if_get(rt->rt_ifidx); 1495 if (ifp == NULL) 1496 return (EHOSTUNREACH); 1497 /* 1498 * XXX: we dot not consider the case of source 1499 * routing, or optional information to specify 1500 * the outgoing interface. 1501 */ 1502 error = ip6_getpmtu(rt, ifp, &pmtu); 1503 if_put(ifp); 1504 if (error) 1505 break; 1506 if (pmtu > IPV6_MAXPACKET) 1507 pmtu = IPV6_MAXPACKET; 1508 1509 bzero(&mtuinfo, sizeof(mtuinfo)); 1510 mtuinfo.ip6m_mtu = (u_int32_t)pmtu; 1511 optdata = (void *)&mtuinfo; 1512 optdatalen = sizeof(mtuinfo); 1513 if (optdatalen > MCLBYTES) 1514 return (EMSGSIZE); /* XXX */ 1515 if (optdatalen > MLEN) 1516 MCLGET(m, M_WAIT); 1517 m->m_len = optdatalen; 1518 bcopy(optdata, mtod(m, void *), optdatalen); 1519 break; 1520 } 1521 1522 case IPV6_PKTINFO: 1523 case IPV6_HOPOPTS: 1524 case IPV6_RTHDR: 1525 case IPV6_DSTOPTS: 1526 case IPV6_RTHDRDSTOPTS: 1527 case IPV6_TCLASS: 1528 case IPV6_DONTFRAG: 1529 case IPV6_USE_MIN_MTU: 1530 error = ip6_getpcbopt(inp->inp_outputopts6, 1531 optname, m); 1532 break; 1533 1534 case IPV6_MULTICAST_IF: 1535 case IPV6_MULTICAST_HOPS: 1536 case IPV6_MULTICAST_LOOP: 1537 case IPV6_JOIN_GROUP: 1538 case IPV6_LEAVE_GROUP: 1539 error = ip6_getmoptions(optname, 1540 inp->inp_moptions6, m); 1541 break; 1542 1543 case IPSEC6_OUTSA: 1544 error = EINVAL; 1545 break; 1546 1547 case IPV6_AUTH_LEVEL: 1548 case IPV6_ESP_TRANS_LEVEL: 1549 case IPV6_ESP_NETWORK_LEVEL: 1550 case IPV6_IPCOMP_LEVEL: 1551 #ifndef IPSEC 1552 m->m_len = sizeof(int); 1553 *mtod(m, int *) = IPSEC_LEVEL_NONE; 1554 #else 1555 m->m_len = sizeof(int); 1556 switch (optname) { 1557 case IPV6_AUTH_LEVEL: 1558 optval = inp->inp_seclevel[SL_AUTH]; 1559 break; 1560 1561 case IPV6_ESP_TRANS_LEVEL: 1562 optval = 1563 inp->inp_seclevel[SL_ESP_TRANS]; 1564 break; 1565 1566 case IPV6_ESP_NETWORK_LEVEL: 1567 optval = 1568 inp->inp_seclevel[SL_ESP_NETWORK]; 1569 break; 1570 1571 case IPV6_IPCOMP_LEVEL: 1572 optval = inp->inp_seclevel[SL_IPCOMP]; 1573 break; 1574 } 1575 *mtod(m, int *) = optval; 1576 #endif 1577 break; 1578 case SO_RTABLE: 1579 m->m_len = sizeof(u_int); 1580 *mtod(m, u_int *) = inp->inp_rtableid; 1581 break; 1582 case IPV6_PIPEX: 1583 m->m_len = sizeof(int); 1584 *mtod(m, int *) = inp->inp_pipex; 1585 break; 1586 1587 default: 1588 error = ENOPROTOOPT; 1589 break; 1590 } 1591 break; 1592 } 1593 return (error); 1594 } 1595 1596 int 1597 ip6_raw_ctloutput(int op, struct socket *so, int level, int optname, 1598 struct mbuf *m) 1599 { 1600 int error = 0, optval; 1601 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); 1602 struct inpcb *inp = sotoinpcb(so); 1603 1604 if (level != IPPROTO_IPV6) 1605 return (EINVAL); 1606 1607 switch (optname) { 1608 case IPV6_CHECKSUM: 1609 /* 1610 * For ICMPv6 sockets, no modification allowed for checksum 1611 * offset, permit "no change" values to help existing apps. 1612 * 1613 * RFC3542 says: "An attempt to set IPV6_CHECKSUM 1614 * for an ICMPv6 socket will fail." 1615 * The current behavior does not meet RFC3542. 1616 */ 1617 switch (op) { 1618 case PRCO_SETOPT: 1619 if (m == NULL || m->m_len != sizeof(int)) { 1620 error = EINVAL; 1621 break; 1622 } 1623 optval = *mtod(m, int *); 1624 if (optval < -1 || 1625 (optval > 0 && (optval % 2) != 0)) { 1626 /* 1627 * The API assumes non-negative even offset 1628 * values or -1 as a special value. 1629 */ 1630 error = EINVAL; 1631 } else if (so->so_proto->pr_protocol == 1632 IPPROTO_ICMPV6) { 1633 if (optval != icmp6off) 1634 error = EINVAL; 1635 } else 1636 inp->inp_cksum6 = optval; 1637 break; 1638 1639 case PRCO_GETOPT: 1640 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) 1641 optval = icmp6off; 1642 else 1643 optval = inp->inp_cksum6; 1644 1645 m->m_len = sizeof(int); 1646 *mtod(m, int *) = optval; 1647 break; 1648 1649 default: 1650 error = EINVAL; 1651 break; 1652 } 1653 break; 1654 1655 default: 1656 error = ENOPROTOOPT; 1657 break; 1658 } 1659 1660 return (error); 1661 } 1662 1663 /* 1664 * initialize ip6_pktopts. beware that there are non-zero default values in 1665 * the struct. 1666 */ 1667 void 1668 ip6_initpktopts(struct ip6_pktopts *opt) 1669 { 1670 bzero(opt, sizeof(*opt)); 1671 opt->ip6po_hlim = -1; /* -1 means default hop limit */ 1672 opt->ip6po_tclass = -1; /* -1 means default traffic class */ 1673 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY; 1674 } 1675 1676 int 1677 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt, 1678 int priv, int uproto) 1679 { 1680 struct ip6_pktopts *opt; 1681 1682 if (*pktopt == NULL) { 1683 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT, 1684 M_WAITOK); 1685 ip6_initpktopts(*pktopt); 1686 } 1687 opt = *pktopt; 1688 1689 return (ip6_setpktopt(optname, buf, len, opt, priv, 1, uproto)); 1690 } 1691 1692 int 1693 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct mbuf *m) 1694 { 1695 void *optdata = NULL; 1696 int optdatalen = 0; 1697 struct ip6_ext *ip6e; 1698 int error = 0; 1699 struct in6_pktinfo null_pktinfo; 1700 int deftclass = 0, on; 1701 int defminmtu = IP6PO_MINMTU_MCASTONLY; 1702 1703 switch (optname) { 1704 case IPV6_PKTINFO: 1705 if (pktopt && pktopt->ip6po_pktinfo) 1706 optdata = (void *)pktopt->ip6po_pktinfo; 1707 else { 1708 /* XXX: we don't have to do this every time... */ 1709 bzero(&null_pktinfo, sizeof(null_pktinfo)); 1710 optdata = (void *)&null_pktinfo; 1711 } 1712 optdatalen = sizeof(struct in6_pktinfo); 1713 break; 1714 case IPV6_TCLASS: 1715 if (pktopt && pktopt->ip6po_tclass >= 0) 1716 optdata = (void *)&pktopt->ip6po_tclass; 1717 else 1718 optdata = (void *)&deftclass; 1719 optdatalen = sizeof(int); 1720 break; 1721 case IPV6_HOPOPTS: 1722 if (pktopt && pktopt->ip6po_hbh) { 1723 optdata = (void *)pktopt->ip6po_hbh; 1724 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh; 1725 optdatalen = (ip6e->ip6e_len + 1) << 3; 1726 } 1727 break; 1728 case IPV6_RTHDR: 1729 if (pktopt && pktopt->ip6po_rthdr) { 1730 optdata = (void *)pktopt->ip6po_rthdr; 1731 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr; 1732 optdatalen = (ip6e->ip6e_len + 1) << 3; 1733 } 1734 break; 1735 case IPV6_RTHDRDSTOPTS: 1736 if (pktopt && pktopt->ip6po_dest1) { 1737 optdata = (void *)pktopt->ip6po_dest1; 1738 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1; 1739 optdatalen = (ip6e->ip6e_len + 1) << 3; 1740 } 1741 break; 1742 case IPV6_DSTOPTS: 1743 if (pktopt && pktopt->ip6po_dest2) { 1744 optdata = (void *)pktopt->ip6po_dest2; 1745 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2; 1746 optdatalen = (ip6e->ip6e_len + 1) << 3; 1747 } 1748 break; 1749 case IPV6_USE_MIN_MTU: 1750 if (pktopt) 1751 optdata = (void *)&pktopt->ip6po_minmtu; 1752 else 1753 optdata = (void *)&defminmtu; 1754 optdatalen = sizeof(int); 1755 break; 1756 case IPV6_DONTFRAG: 1757 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG)) 1758 on = 1; 1759 else 1760 on = 0; 1761 optdata = (void *)&on; 1762 optdatalen = sizeof(on); 1763 break; 1764 default: /* should not happen */ 1765 #ifdef DIAGNOSTIC 1766 panic("%s: unexpected option", __func__); 1767 #endif 1768 return (ENOPROTOOPT); 1769 } 1770 1771 if (optdatalen > MCLBYTES) 1772 return (EMSGSIZE); /* XXX */ 1773 if (optdatalen > MLEN) 1774 MCLGET(m, M_WAIT); 1775 m->m_len = optdatalen; 1776 if (optdatalen) 1777 bcopy(optdata, mtod(m, void *), optdatalen); 1778 1779 return (error); 1780 } 1781 1782 void 1783 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname) 1784 { 1785 if (optname == -1 || optname == IPV6_PKTINFO) { 1786 if (pktopt->ip6po_pktinfo) 1787 free(pktopt->ip6po_pktinfo, M_IP6OPT, 0); 1788 pktopt->ip6po_pktinfo = NULL; 1789 } 1790 if (optname == -1 || optname == IPV6_HOPLIMIT) 1791 pktopt->ip6po_hlim = -1; 1792 if (optname == -1 || optname == IPV6_TCLASS) 1793 pktopt->ip6po_tclass = -1; 1794 if (optname == -1 || optname == IPV6_HOPOPTS) { 1795 if (pktopt->ip6po_hbh) 1796 free(pktopt->ip6po_hbh, M_IP6OPT, 0); 1797 pktopt->ip6po_hbh = NULL; 1798 } 1799 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) { 1800 if (pktopt->ip6po_dest1) 1801 free(pktopt->ip6po_dest1, M_IP6OPT, 0); 1802 pktopt->ip6po_dest1 = NULL; 1803 } 1804 if (optname == -1 || optname == IPV6_RTHDR) { 1805 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr) 1806 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT, 0); 1807 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL; 1808 if (pktopt->ip6po_route.ro_rt) { 1809 rtfree(pktopt->ip6po_route.ro_rt); 1810 pktopt->ip6po_route.ro_rt = NULL; 1811 } 1812 } 1813 if (optname == -1 || optname == IPV6_DSTOPTS) { 1814 if (pktopt->ip6po_dest2) 1815 free(pktopt->ip6po_dest2, M_IP6OPT, 0); 1816 pktopt->ip6po_dest2 = NULL; 1817 } 1818 } 1819 1820 #define PKTOPT_EXTHDRCPY(type) \ 1821 do {\ 1822 if (src->type) {\ 1823 size_t hlen;\ 1824 hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\ 1825 dst->type = malloc(hlen, M_IP6OPT, M_NOWAIT);\ 1826 if (dst->type == NULL)\ 1827 goto bad;\ 1828 memcpy(dst->type, src->type, hlen);\ 1829 }\ 1830 } while (/*CONSTCOND*/ 0) 1831 1832 int 1833 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src) 1834 { 1835 dst->ip6po_hlim = src->ip6po_hlim; 1836 dst->ip6po_tclass = src->ip6po_tclass; 1837 dst->ip6po_flags = src->ip6po_flags; 1838 if (src->ip6po_pktinfo) { 1839 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo), 1840 M_IP6OPT, M_NOWAIT); 1841 if (dst->ip6po_pktinfo == NULL) 1842 goto bad; 1843 *dst->ip6po_pktinfo = *src->ip6po_pktinfo; 1844 } 1845 PKTOPT_EXTHDRCPY(ip6po_hbh); 1846 PKTOPT_EXTHDRCPY(ip6po_dest1); 1847 PKTOPT_EXTHDRCPY(ip6po_dest2); 1848 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */ 1849 return (0); 1850 1851 bad: 1852 ip6_clearpktopts(dst, -1); 1853 return (ENOBUFS); 1854 } 1855 #undef PKTOPT_EXTHDRCPY 1856 1857 void 1858 ip6_freepcbopts(struct ip6_pktopts *pktopt) 1859 { 1860 if (pktopt == NULL) 1861 return; 1862 1863 ip6_clearpktopts(pktopt, -1); 1864 1865 free(pktopt, M_IP6OPT, 0); 1866 } 1867 1868 /* 1869 * Set the IP6 multicast options in response to user setsockopt(). 1870 */ 1871 int 1872 ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m, 1873 unsigned int rtableid) 1874 { 1875 int error = 0; 1876 u_int loop, ifindex; 1877 struct ipv6_mreq *mreq; 1878 struct ifnet *ifp; 1879 struct ip6_moptions *im6o = *im6op; 1880 struct in6_multi_mship *imm; 1881 struct proc *p = curproc; /* XXX */ 1882 1883 if (im6o == NULL) { 1884 /* 1885 * No multicast option buffer attached to the pcb; 1886 * allocate one and initialize to default values. 1887 */ 1888 im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK); 1889 if (im6o == NULL) 1890 return (ENOBUFS); 1891 *im6op = im6o; 1892 im6o->im6o_ifidx = 0; 1893 im6o->im6o_hlim = ip6_defmcasthlim; 1894 im6o->im6o_loop = IPV6_DEFAULT_MULTICAST_LOOP; 1895 LIST_INIT(&im6o->im6o_memberships); 1896 } 1897 1898 switch (optname) { 1899 1900 case IPV6_MULTICAST_IF: 1901 /* 1902 * Select the interface for outgoing multicast packets. 1903 */ 1904 if (m == NULL || m->m_len != sizeof(u_int)) { 1905 error = EINVAL; 1906 break; 1907 } 1908 memcpy(&ifindex, mtod(m, u_int *), sizeof(ifindex)); 1909 if (ifindex != 0) { 1910 ifp = if_get(ifindex); 1911 if (ifp == NULL) { 1912 error = ENXIO; /* XXX EINVAL? */ 1913 break; 1914 } 1915 if (ifp->if_rdomain != rtable_l2(rtableid) || 1916 (ifp->if_flags & IFF_MULTICAST) == 0) { 1917 error = EADDRNOTAVAIL; 1918 if_put(ifp); 1919 break; 1920 } 1921 if_put(ifp); 1922 } 1923 im6o->im6o_ifidx = ifindex; 1924 break; 1925 1926 case IPV6_MULTICAST_HOPS: 1927 { 1928 /* 1929 * Set the IP6 hoplimit for outgoing multicast packets. 1930 */ 1931 int optval; 1932 if (m == NULL || m->m_len != sizeof(int)) { 1933 error = EINVAL; 1934 break; 1935 } 1936 memcpy(&optval, mtod(m, u_int *), sizeof(optval)); 1937 if (optval < -1 || optval >= 256) 1938 error = EINVAL; 1939 else if (optval == -1) 1940 im6o->im6o_hlim = ip6_defmcasthlim; 1941 else 1942 im6o->im6o_hlim = optval; 1943 break; 1944 } 1945 1946 case IPV6_MULTICAST_LOOP: 1947 /* 1948 * Set the loopback flag for outgoing multicast packets. 1949 * Must be zero or one. 1950 */ 1951 if (m == NULL || m->m_len != sizeof(u_int)) { 1952 error = EINVAL; 1953 break; 1954 } 1955 memcpy(&loop, mtod(m, u_int *), sizeof(loop)); 1956 if (loop > 1) { 1957 error = EINVAL; 1958 break; 1959 } 1960 im6o->im6o_loop = loop; 1961 break; 1962 1963 case IPV6_JOIN_GROUP: 1964 /* 1965 * Add a multicast group membership. 1966 * Group must be a valid IP6 multicast address. 1967 */ 1968 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { 1969 error = EINVAL; 1970 break; 1971 } 1972 mreq = mtod(m, struct ipv6_mreq *); 1973 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { 1974 /* 1975 * We use the unspecified address to specify to accept 1976 * all multicast addresses. Only super user is allowed 1977 * to do this. 1978 */ 1979 if (suser(p)) 1980 { 1981 error = EACCES; 1982 break; 1983 } 1984 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { 1985 error = EINVAL; 1986 break; 1987 } 1988 1989 /* 1990 * If no interface was explicitly specified, choose an 1991 * appropriate one according to the given multicast address. 1992 */ 1993 if (mreq->ipv6mr_interface == 0) { 1994 struct rtentry *rt; 1995 struct sockaddr_in6 dst; 1996 1997 memset(&dst, 0, sizeof(dst)); 1998 dst.sin6_len = sizeof(dst); 1999 dst.sin6_family = AF_INET6; 2000 dst.sin6_addr = mreq->ipv6mr_multiaddr; 2001 rt = rtalloc(sin6tosa(&dst), RT_RESOLVE, rtableid); 2002 if (rt == NULL) { 2003 error = EADDRNOTAVAIL; 2004 break; 2005 } 2006 ifp = if_get(rt->rt_ifidx); 2007 rtfree(rt); 2008 } else { 2009 /* 2010 * If the interface is specified, validate it. 2011 */ 2012 ifp = if_get(mreq->ipv6mr_interface); 2013 if (ifp == NULL) { 2014 error = ENXIO; /* XXX EINVAL? */ 2015 break; 2016 } 2017 } 2018 2019 /* 2020 * See if we found an interface, and confirm that it 2021 * supports multicast 2022 */ 2023 if (ifp == NULL || ifp->if_rdomain != rtable_l2(rtableid) || 2024 (ifp->if_flags & IFF_MULTICAST) == 0) { 2025 if_put(ifp); 2026 error = EADDRNOTAVAIL; 2027 break; 2028 } 2029 /* 2030 * Put interface index into the multicast address, 2031 * if the address has link/interface-local scope. 2032 */ 2033 if (IN6_IS_SCOPE_EMBED(&mreq->ipv6mr_multiaddr)) { 2034 mreq->ipv6mr_multiaddr.s6_addr16[1] = 2035 htons(ifp->if_index); 2036 } 2037 /* 2038 * See if the membership already exists. 2039 */ 2040 LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) 2041 if (imm->i6mm_maddr->in6m_ifidx == ifp->if_index && 2042 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2043 &mreq->ipv6mr_multiaddr)) 2044 break; 2045 if (imm != NULL) { 2046 if_put(ifp); 2047 error = EADDRINUSE; 2048 break; 2049 } 2050 /* 2051 * Everything looks good; add a new record to the multicast 2052 * address list for the given interface. 2053 */ 2054 imm = in6_joingroup(ifp, &mreq->ipv6mr_multiaddr, &error); 2055 if_put(ifp); 2056 if (!imm) 2057 break; 2058 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); 2059 break; 2060 2061 case IPV6_LEAVE_GROUP: 2062 /* 2063 * Drop a multicast group membership. 2064 * Group must be a valid IP6 multicast address. 2065 */ 2066 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { 2067 error = EINVAL; 2068 break; 2069 } 2070 mreq = mtod(m, struct ipv6_mreq *); 2071 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { 2072 if (suser(p)) { 2073 error = EACCES; 2074 break; 2075 } 2076 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { 2077 error = EINVAL; 2078 break; 2079 } 2080 2081 /* 2082 * Put interface index into the multicast address, 2083 * if the address has link-local scope. 2084 */ 2085 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) { 2086 mreq->ipv6mr_multiaddr.s6_addr16[1] = 2087 htons(mreq->ipv6mr_interface); 2088 } 2089 2090 /* 2091 * If an interface address was specified, get a pointer 2092 * to its ifnet structure. 2093 */ 2094 if (mreq->ipv6mr_interface == 0) 2095 ifp = NULL; 2096 else { 2097 ifp = if_get(mreq->ipv6mr_interface); 2098 if (ifp == NULL) { 2099 error = ENXIO; /* XXX EINVAL? */ 2100 break; 2101 } 2102 } 2103 2104 /* 2105 * Find the membership in the membership list. 2106 */ 2107 LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) { 2108 if ((ifp == NULL || 2109 imm->i6mm_maddr->in6m_ifidx == ifp->if_index) && 2110 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2111 &mreq->ipv6mr_multiaddr)) 2112 break; 2113 } 2114 2115 if_put(ifp); 2116 2117 if (imm == NULL) { 2118 /* Unable to resolve interface */ 2119 error = EADDRNOTAVAIL; 2120 break; 2121 } 2122 /* 2123 * Give up the multicast address record to which the 2124 * membership points. 2125 */ 2126 LIST_REMOVE(imm, i6mm_chain); 2127 in6_leavegroup(imm); 2128 break; 2129 2130 default: 2131 error = EOPNOTSUPP; 2132 break; 2133 } 2134 2135 /* 2136 * If all options have default values, no need to keep the option 2137 * structure. 2138 */ 2139 if (im6o->im6o_ifidx == 0 && 2140 im6o->im6o_hlim == ip6_defmcasthlim && 2141 im6o->im6o_loop == IPV6_DEFAULT_MULTICAST_LOOP && 2142 LIST_EMPTY(&im6o->im6o_memberships)) { 2143 free(*im6op, M_IPMOPTS, sizeof(**im6op)); 2144 *im6op = NULL; 2145 } 2146 2147 return (error); 2148 } 2149 2150 /* 2151 * Return the IP6 multicast options in response to user getsockopt(). 2152 */ 2153 int 2154 ip6_getmoptions(int optname, struct ip6_moptions *im6o, struct mbuf *m) 2155 { 2156 u_int *hlim, *loop, *ifindex; 2157 2158 switch (optname) { 2159 case IPV6_MULTICAST_IF: 2160 ifindex = mtod(m, u_int *); 2161 m->m_len = sizeof(u_int); 2162 if (im6o == NULL || im6o->im6o_ifidx == 0) 2163 *ifindex = 0; 2164 else 2165 *ifindex = im6o->im6o_ifidx; 2166 return (0); 2167 2168 case IPV6_MULTICAST_HOPS: 2169 hlim = mtod(m, u_int *); 2170 m->m_len = sizeof(u_int); 2171 if (im6o == NULL) 2172 *hlim = ip6_defmcasthlim; 2173 else 2174 *hlim = im6o->im6o_hlim; 2175 return (0); 2176 2177 case IPV6_MULTICAST_LOOP: 2178 loop = mtod(m, u_int *); 2179 m->m_len = sizeof(u_int); 2180 if (im6o == NULL) 2181 *loop = ip6_defmcasthlim; 2182 else 2183 *loop = im6o->im6o_loop; 2184 return (0); 2185 2186 default: 2187 return (EOPNOTSUPP); 2188 } 2189 } 2190 2191 /* 2192 * Discard the IP6 multicast options. 2193 */ 2194 void 2195 ip6_freemoptions(struct ip6_moptions *im6o) 2196 { 2197 struct in6_multi_mship *imm; 2198 2199 if (im6o == NULL) 2200 return; 2201 2202 while (!LIST_EMPTY(&im6o->im6o_memberships)) { 2203 imm = LIST_FIRST(&im6o->im6o_memberships); 2204 LIST_REMOVE(imm, i6mm_chain); 2205 in6_leavegroup(imm); 2206 } 2207 free(im6o, M_IPMOPTS, sizeof(*im6o)); 2208 } 2209 2210 /* 2211 * Set IPv6 outgoing packet options based on advanced API. 2212 */ 2213 int 2214 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt, 2215 struct ip6_pktopts *stickyopt, int priv, int uproto) 2216 { 2217 u_int clen; 2218 struct cmsghdr *cm = 0; 2219 caddr_t cmsgs; 2220 int error; 2221 2222 if (control == NULL || opt == NULL) 2223 return (EINVAL); 2224 2225 ip6_initpktopts(opt); 2226 if (stickyopt) { 2227 int error; 2228 2229 /* 2230 * If stickyopt is provided, make a local copy of the options 2231 * for this particular packet, then override them by ancillary 2232 * objects. 2233 * XXX: copypktopts() does not copy the cached route to a next 2234 * hop (if any). This is not very good in terms of efficiency, 2235 * but we can allow this since this option should be rarely 2236 * used. 2237 */ 2238 if ((error = copypktopts(opt, stickyopt)) != 0) 2239 return (error); 2240 } 2241 2242 /* 2243 * XXX: Currently, we assume all the optional information is stored 2244 * in a single mbuf. 2245 */ 2246 if (control->m_next) 2247 return (EINVAL); 2248 2249 clen = control->m_len; 2250 cmsgs = mtod(control, caddr_t); 2251 do { 2252 if (clen < CMSG_LEN(0)) 2253 return (EINVAL); 2254 cm = (struct cmsghdr *)cmsgs; 2255 if (cm->cmsg_len < CMSG_LEN(0) || cm->cmsg_len > clen || 2256 CMSG_ALIGN(cm->cmsg_len) > clen) 2257 return (EINVAL); 2258 if (cm->cmsg_level == IPPROTO_IPV6) { 2259 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm), 2260 cm->cmsg_len - CMSG_LEN(0), opt, priv, 0, uproto); 2261 if (error) 2262 return (error); 2263 } 2264 2265 clen -= CMSG_ALIGN(cm->cmsg_len); 2266 cmsgs += CMSG_ALIGN(cm->cmsg_len); 2267 } while (clen); 2268 2269 return (0); 2270 } 2271 2272 /* 2273 * Set a particular packet option, as a sticky option or an ancillary data 2274 * item. "len" can be 0 only when it's a sticky option. 2275 */ 2276 int 2277 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt, 2278 int priv, int sticky, int uproto) 2279 { 2280 int minmtupolicy; 2281 2282 switch (optname) { 2283 case IPV6_PKTINFO: 2284 { 2285 struct ifnet *ifp = NULL; 2286 struct in6_pktinfo *pktinfo; 2287 2288 if (len != sizeof(struct in6_pktinfo)) 2289 return (EINVAL); 2290 2291 pktinfo = (struct in6_pktinfo *)buf; 2292 2293 /* 2294 * An application can clear any sticky IPV6_PKTINFO option by 2295 * doing a "regular" setsockopt with ipi6_addr being 2296 * in6addr_any and ipi6_ifindex being zero. 2297 * [RFC 3542, Section 6] 2298 */ 2299 if (opt->ip6po_pktinfo && 2300 pktinfo->ipi6_ifindex == 0 && 2301 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2302 ip6_clearpktopts(opt, optname); 2303 break; 2304 } 2305 2306 if (uproto == IPPROTO_TCP && 2307 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2308 return (EINVAL); 2309 } 2310 2311 if (pktinfo->ipi6_ifindex) { 2312 ifp = if_get(pktinfo->ipi6_ifindex); 2313 if (ifp == NULL) 2314 return (ENXIO); 2315 if_put(ifp); 2316 } 2317 2318 /* 2319 * We store the address anyway, and let in6_selectsrc() 2320 * validate the specified address. This is because ipi6_addr 2321 * may not have enough information about its scope zone, and 2322 * we may need additional information (such as outgoing 2323 * interface or the scope zone of a destination address) to 2324 * disambiguate the scope. 2325 * XXX: the delay of the validation may confuse the 2326 * application when it is used as a sticky option. 2327 */ 2328 if (opt->ip6po_pktinfo == NULL) { 2329 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo), 2330 M_IP6OPT, M_NOWAIT); 2331 if (opt->ip6po_pktinfo == NULL) 2332 return (ENOBUFS); 2333 } 2334 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo)); 2335 break; 2336 } 2337 2338 case IPV6_HOPLIMIT: 2339 { 2340 int *hlimp; 2341 2342 /* 2343 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT 2344 * to simplify the ordering among hoplimit options. 2345 */ 2346 if (sticky) 2347 return (ENOPROTOOPT); 2348 2349 if (len != sizeof(int)) 2350 return (EINVAL); 2351 hlimp = (int *)buf; 2352 if (*hlimp < -1 || *hlimp > 255) 2353 return (EINVAL); 2354 2355 opt->ip6po_hlim = *hlimp; 2356 break; 2357 } 2358 2359 case IPV6_TCLASS: 2360 { 2361 int tclass; 2362 2363 if (len != sizeof(int)) 2364 return (EINVAL); 2365 tclass = *(int *)buf; 2366 if (tclass < -1 || tclass > 255) 2367 return (EINVAL); 2368 2369 opt->ip6po_tclass = tclass; 2370 break; 2371 } 2372 case IPV6_HOPOPTS: 2373 { 2374 struct ip6_hbh *hbh; 2375 int hbhlen; 2376 2377 /* 2378 * XXX: We don't allow a non-privileged user to set ANY HbH 2379 * options, since per-option restriction has too much 2380 * overhead. 2381 */ 2382 if (!priv) 2383 return (EPERM); 2384 2385 if (len == 0) { 2386 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2387 break; /* just remove the option */ 2388 } 2389 2390 /* message length validation */ 2391 if (len < sizeof(struct ip6_hbh)) 2392 return (EINVAL); 2393 hbh = (struct ip6_hbh *)buf; 2394 hbhlen = (hbh->ip6h_len + 1) << 3; 2395 if (len != hbhlen) 2396 return (EINVAL); 2397 2398 /* turn off the previous option, then set the new option. */ 2399 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2400 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT); 2401 if (opt->ip6po_hbh == NULL) 2402 return (ENOBUFS); 2403 memcpy(opt->ip6po_hbh, hbh, hbhlen); 2404 2405 break; 2406 } 2407 2408 case IPV6_DSTOPTS: 2409 case IPV6_RTHDRDSTOPTS: 2410 { 2411 struct ip6_dest *dest, **newdest = NULL; 2412 int destlen; 2413 2414 if (!priv) /* XXX: see the comment for IPV6_HOPOPTS */ 2415 return (EPERM); 2416 2417 if (len == 0) { 2418 ip6_clearpktopts(opt, optname); 2419 break; /* just remove the option */ 2420 } 2421 2422 /* message length validation */ 2423 if (len < sizeof(struct ip6_dest)) 2424 return (EINVAL); 2425 dest = (struct ip6_dest *)buf; 2426 destlen = (dest->ip6d_len + 1) << 3; 2427 if (len != destlen) 2428 return (EINVAL); 2429 /* 2430 * Determine the position that the destination options header 2431 * should be inserted; before or after the routing header. 2432 */ 2433 switch (optname) { 2434 case IPV6_RTHDRDSTOPTS: 2435 newdest = &opt->ip6po_dest1; 2436 break; 2437 case IPV6_DSTOPTS: 2438 newdest = &opt->ip6po_dest2; 2439 break; 2440 } 2441 2442 /* turn off the previous option, then set the new option. */ 2443 ip6_clearpktopts(opt, optname); 2444 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT); 2445 if (*newdest == NULL) 2446 return (ENOBUFS); 2447 memcpy(*newdest, dest, destlen); 2448 2449 break; 2450 } 2451 2452 case IPV6_RTHDR: 2453 { 2454 struct ip6_rthdr *rth; 2455 int rthlen; 2456 2457 if (len == 0) { 2458 ip6_clearpktopts(opt, IPV6_RTHDR); 2459 break; /* just remove the option */ 2460 } 2461 2462 /* message length validation */ 2463 if (len < sizeof(struct ip6_rthdr)) 2464 return (EINVAL); 2465 rth = (struct ip6_rthdr *)buf; 2466 rthlen = (rth->ip6r_len + 1) << 3; 2467 if (len != rthlen) 2468 return (EINVAL); 2469 2470 switch (rth->ip6r_type) { 2471 case IPV6_RTHDR_TYPE_0: 2472 if (rth->ip6r_len == 0) /* must contain one addr */ 2473 return (EINVAL); 2474 if (rth->ip6r_len % 2) /* length must be even */ 2475 return (EINVAL); 2476 if (rth->ip6r_len / 2 != rth->ip6r_segleft) 2477 return (EINVAL); 2478 break; 2479 default: 2480 return (EINVAL); /* not supported */ 2481 } 2482 /* turn off the previous option */ 2483 ip6_clearpktopts(opt, IPV6_RTHDR); 2484 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT); 2485 if (opt->ip6po_rthdr == NULL) 2486 return (ENOBUFS); 2487 memcpy(opt->ip6po_rthdr, rth, rthlen); 2488 break; 2489 } 2490 2491 case IPV6_USE_MIN_MTU: 2492 if (len != sizeof(int)) 2493 return (EINVAL); 2494 minmtupolicy = *(int *)buf; 2495 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY && 2496 minmtupolicy != IP6PO_MINMTU_DISABLE && 2497 minmtupolicy != IP6PO_MINMTU_ALL) { 2498 return (EINVAL); 2499 } 2500 opt->ip6po_minmtu = minmtupolicy; 2501 break; 2502 2503 case IPV6_DONTFRAG: 2504 if (len != sizeof(int)) 2505 return (EINVAL); 2506 2507 if (uproto == IPPROTO_TCP || *(int *)buf == 0) { 2508 /* 2509 * we ignore this option for TCP sockets. 2510 * (RFC3542 leaves this case unspecified.) 2511 */ 2512 opt->ip6po_flags &= ~IP6PO_DONTFRAG; 2513 } else 2514 opt->ip6po_flags |= IP6PO_DONTFRAG; 2515 break; 2516 2517 default: 2518 return (ENOPROTOOPT); 2519 } /* end of switch */ 2520 2521 return (0); 2522 } 2523 2524 /* 2525 * Routine called from ip6_output() to loop back a copy of an IP6 multicast 2526 * packet to the input queue of a specified interface. 2527 */ 2528 void 2529 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in6 *dst) 2530 { 2531 struct mbuf *copym; 2532 struct ip6_hdr *ip6; 2533 2534 /* 2535 * Duplicate the packet. 2536 */ 2537 copym = m_copym(m, 0, M_COPYALL, M_NOWAIT); 2538 if (copym == NULL) 2539 return; 2540 2541 /* 2542 * Make sure to deep-copy IPv6 header portion in case the data 2543 * is in an mbuf cluster, so that we can safely override the IPv6 2544 * header portion later. 2545 */ 2546 if ((copym->m_flags & M_EXT) != 0 || 2547 copym->m_len < sizeof(struct ip6_hdr)) { 2548 copym = m_pullup(copym, sizeof(struct ip6_hdr)); 2549 if (copym == NULL) 2550 return; 2551 } 2552 2553 #ifdef DIAGNOSTIC 2554 if (copym->m_len < sizeof(*ip6)) { 2555 m_freem(copym); 2556 return; 2557 } 2558 #endif 2559 2560 ip6 = mtod(copym, struct ip6_hdr *); 2561 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 2562 ip6->ip6_src.s6_addr16[1] = 0; 2563 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 2564 ip6->ip6_dst.s6_addr16[1] = 0; 2565 2566 if_input_local(ifp, copym, dst->sin6_family); 2567 } 2568 2569 /* 2570 * Chop IPv6 header off from the payload. 2571 */ 2572 int 2573 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs) 2574 { 2575 struct mbuf *mh; 2576 struct ip6_hdr *ip6; 2577 2578 ip6 = mtod(m, struct ip6_hdr *); 2579 if (m->m_len > sizeof(*ip6)) { 2580 MGET(mh, M_DONTWAIT, MT_HEADER); 2581 if (mh == NULL) { 2582 m_freem(m); 2583 return ENOBUFS; 2584 } 2585 M_MOVE_PKTHDR(mh, m); 2586 m_align(mh, sizeof(*ip6)); 2587 m->m_len -= sizeof(*ip6); 2588 m->m_data += sizeof(*ip6); 2589 mh->m_next = m; 2590 m = mh; 2591 m->m_len = sizeof(*ip6); 2592 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6)); 2593 } 2594 exthdrs->ip6e_ip6 = m; 2595 return 0; 2596 } 2597 2598 u_int32_t 2599 ip6_randomid(void) 2600 { 2601 return idgen32(&ip6_id_ctx); 2602 } 2603 2604 void 2605 ip6_randomid_init(void) 2606 { 2607 idgen32_init(&ip6_id_ctx); 2608 } 2609 2610 /* 2611 * Compute significant parts of the IPv6 checksum pseudo-header 2612 * for use in a delayed TCP/UDP checksum calculation. 2613 */ 2614 static __inline u_int16_t __attribute__((__unused__)) 2615 in6_cksum_phdr(const struct in6_addr *src, const struct in6_addr *dst, 2616 u_int32_t len, u_int32_t nxt) 2617 { 2618 u_int32_t sum = 0; 2619 const u_int16_t *w; 2620 2621 w = (const u_int16_t *) src; 2622 sum += w[0]; 2623 if (!IN6_IS_SCOPE_EMBED(src)) 2624 sum += w[1]; 2625 sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5]; 2626 sum += w[6]; sum += w[7]; 2627 2628 w = (const u_int16_t *) dst; 2629 sum += w[0]; 2630 if (!IN6_IS_SCOPE_EMBED(dst)) 2631 sum += w[1]; 2632 sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5]; 2633 sum += w[6]; sum += w[7]; 2634 2635 sum += (u_int16_t)(len >> 16) + (u_int16_t)(len /*& 0xffff*/); 2636 2637 sum += (u_int16_t)(nxt >> 16) + (u_int16_t)(nxt /*& 0xffff*/); 2638 2639 sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/); 2640 2641 if (sum > 0xffff) 2642 sum -= 0xffff; 2643 2644 return (sum); 2645 } 2646 2647 /* 2648 * Process a delayed payload checksum calculation. 2649 */ 2650 void 2651 in6_delayed_cksum(struct mbuf *m, u_int8_t nxt) 2652 { 2653 int nxtp, offset; 2654 u_int16_t csum; 2655 2656 offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxtp); 2657 if (offset <= 0 || nxtp != nxt) 2658 /* If the desired next protocol isn't found, punt. */ 2659 return; 2660 csum = (u_int16_t)(in6_cksum(m, 0, offset, m->m_pkthdr.len - offset)); 2661 2662 switch (nxt) { 2663 case IPPROTO_TCP: 2664 offset += offsetof(struct tcphdr, th_sum); 2665 break; 2666 2667 case IPPROTO_UDP: 2668 offset += offsetof(struct udphdr, uh_sum); 2669 if (csum == 0) 2670 csum = 0xffff; 2671 break; 2672 2673 case IPPROTO_ICMPV6: 2674 offset += offsetof(struct icmp6_hdr, icmp6_cksum); 2675 break; 2676 } 2677 2678 if ((offset + sizeof(u_int16_t)) > m->m_len) 2679 m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT); 2680 else 2681 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; 2682 } 2683 2684 void 2685 in6_proto_cksum_out(struct mbuf *m, struct ifnet *ifp) 2686 { 2687 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2688 2689 /* some hw and in6_delayed_cksum need the pseudo header cksum */ 2690 if (m->m_pkthdr.csum_flags & 2691 (M_TCP_CSUM_OUT|M_UDP_CSUM_OUT|M_ICMP_CSUM_OUT)) { 2692 int nxt, offset; 2693 u_int16_t csum; 2694 2695 offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 2696 csum = in6_cksum_phdr(&ip6->ip6_src, &ip6->ip6_dst, 2697 htonl(m->m_pkthdr.len - offset), htonl(nxt)); 2698 if (nxt == IPPROTO_TCP) 2699 offset += offsetof(struct tcphdr, th_sum); 2700 else if (nxt == IPPROTO_UDP) 2701 offset += offsetof(struct udphdr, uh_sum); 2702 else if (nxt == IPPROTO_ICMPV6) 2703 offset += offsetof(struct icmp6_hdr, icmp6_cksum); 2704 if ((offset + sizeof(u_int16_t)) > m->m_len) 2705 m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT); 2706 else 2707 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; 2708 } 2709 2710 if (m->m_pkthdr.csum_flags & M_TCP_CSUM_OUT) { 2711 if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_TCPv6) || 2712 ip6->ip6_nxt != IPPROTO_TCP || 2713 ifp->if_bridgeidx != 0) { 2714 tcpstat_inc(tcps_outswcsum); 2715 in6_delayed_cksum(m, IPPROTO_TCP); 2716 m->m_pkthdr.csum_flags &= ~M_TCP_CSUM_OUT; /* Clear */ 2717 } 2718 } else if (m->m_pkthdr.csum_flags & M_UDP_CSUM_OUT) { 2719 if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_UDPv6) || 2720 ip6->ip6_nxt != IPPROTO_UDP || 2721 ifp->if_bridgeidx != 0) { 2722 udpstat_inc(udps_outswcsum); 2723 in6_delayed_cksum(m, IPPROTO_UDP); 2724 m->m_pkthdr.csum_flags &= ~M_UDP_CSUM_OUT; /* Clear */ 2725 } 2726 } else if (m->m_pkthdr.csum_flags & M_ICMP_CSUM_OUT) { 2727 in6_delayed_cksum(m, IPPROTO_ICMPV6); 2728 m->m_pkthdr.csum_flags &= ~M_ICMP_CSUM_OUT; /* Clear */ 2729 } 2730 } 2731 2732 #ifdef IPSEC 2733 struct tdb * 2734 ip6_output_ipsec_lookup(struct mbuf *m, int *error, struct inpcb *inp) 2735 { 2736 struct tdb *tdb; 2737 struct m_tag *mtag; 2738 struct tdb_ident *tdbi; 2739 2740 /* 2741 * Check if there was an outgoing SA bound to the flow 2742 * from a transport protocol. 2743 */ 2744 2745 /* Do we have any pending SAs to apply ? */ 2746 tdb = ipsp_spd_lookup(m, AF_INET6, sizeof(struct ip6_hdr), 2747 error, IPSP_DIRECTION_OUT, NULL, inp, 0); 2748 2749 if (tdb == NULL) 2750 return NULL; 2751 /* Loop detection */ 2752 for (mtag = m_tag_first(m); mtag != NULL; mtag = m_tag_next(m, mtag)) { 2753 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE) 2754 continue; 2755 tdbi = (struct tdb_ident *)(mtag + 1); 2756 if (tdbi->spi == tdb->tdb_spi && 2757 tdbi->proto == tdb->tdb_sproto && 2758 tdbi->rdomain == tdb->tdb_rdomain && 2759 !memcmp(&tdbi->dst, &tdb->tdb_dst, 2760 sizeof(union sockaddr_union))) { 2761 /* no IPsec needed */ 2762 return NULL; 2763 } 2764 } 2765 return tdb; 2766 } 2767 2768 int 2769 ip6_output_ipsec_send(struct tdb *tdb, struct mbuf *m, struct route_in6 *ro, 2770 int tunalready, int fwd) 2771 { 2772 #if NPF > 0 2773 struct ifnet *encif; 2774 #endif 2775 struct ip6_hdr *ip6; 2776 int error; 2777 2778 #if NPF > 0 2779 /* 2780 * Packet filter 2781 */ 2782 if ((encif = enc_getif(tdb->tdb_rdomain, tdb->tdb_tap)) == NULL || 2783 pf_test(AF_INET6, fwd ? PF_FWD : PF_OUT, encif, &m) != PF_PASS) { 2784 m_freem(m); 2785 return EACCES; 2786 } 2787 if (m == NULL) 2788 return 0; 2789 /* 2790 * PF_TAG_REROUTE handling or not... 2791 * Packet is entering IPsec so the routing is 2792 * already overruled by the IPsec policy. 2793 * Until now the change was not reconsidered. 2794 * What's the behaviour? 2795 */ 2796 in6_proto_cksum_out(m, encif); 2797 #endif 2798 2799 /* Check if we are allowed to fragment */ 2800 ip6 = mtod(m, struct ip6_hdr *); 2801 if (ip_mtudisc && tdb->tdb_mtu && 2802 sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) > tdb->tdb_mtu && 2803 tdb->tdb_mtutimeout > gettime()) { 2804 struct rtentry *rt = NULL; 2805 int rt_mtucloned = 0; 2806 int transportmode = 0; 2807 2808 transportmode = (tdb->tdb_dst.sa.sa_family == AF_INET6) && 2809 (IN6_ARE_ADDR_EQUAL(&tdb->tdb_dst.sin6.sin6_addr, 2810 &ip6->ip6_dst)); 2811 2812 /* Find a host route to store the mtu in */ 2813 if (ro != NULL) 2814 rt = ro->ro_rt; 2815 /* but don't add a PMTU route for transport mode SAs */ 2816 if (transportmode) 2817 rt = NULL; 2818 else if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0) { 2819 struct sockaddr_in6 sin6; 2820 2821 memset(&sin6, 0, sizeof(sin6)); 2822 sin6.sin6_family = AF_INET6; 2823 sin6.sin6_len = sizeof(sin6); 2824 sin6.sin6_addr = ip6->ip6_dst; 2825 sin6.sin6_scope_id = 2826 in6_addr2scopeid(m->m_pkthdr.ph_ifidx, 2827 &ip6->ip6_dst); 2828 error = in6_embedscope(&ip6->ip6_dst, &sin6, NULL); 2829 if (error) { 2830 /* should be impossible */ 2831 ipsecstat_inc(ipsec_odrops); 2832 m_freem(m); 2833 return error; 2834 } 2835 rt = icmp6_mtudisc_clone(&sin6, 2836 m->m_pkthdr.ph_rtableid, 1); 2837 rt_mtucloned = 1; 2838 } 2839 DPRINTF(("%s: spi %08x mtu %d rt %p cloned %d\n", __func__, 2840 ntohl(tdb->tdb_spi), tdb->tdb_mtu, rt, rt_mtucloned)); 2841 if (rt != NULL) { 2842 rt->rt_mtu = tdb->tdb_mtu; 2843 if (ro != NULL && ro->ro_rt != NULL) { 2844 rtfree(ro->ro_rt); 2845 ro->ro_rt = rtalloc(sin6tosa(&ro->ro_dst), 2846 RT_RESOLVE, m->m_pkthdr.ph_rtableid); 2847 } 2848 if (rt_mtucloned) 2849 rtfree(rt); 2850 } 2851 ipsec_adjust_mtu(m, tdb->tdb_mtu); 2852 m_freem(m); 2853 return EMSGSIZE; 2854 } 2855 /* propagate don't fragment for v6-over-v6 */ 2856 if (ip_mtudisc) 2857 SET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT); 2858 2859 /* 2860 * Clear these -- they'll be set in the recursive invocation 2861 * as needed. 2862 */ 2863 m->m_flags &= ~(M_BCAST | M_MCAST); 2864 2865 /* Callee frees mbuf */ 2866 error = ipsp_process_packet(m, tdb, AF_INET6, tunalready); 2867 if (error) { 2868 ipsecstat_inc(ipsec_odrops); 2869 tdb->tdb_odrops++; 2870 } 2871 return error; 2872 } 2873 #endif /* IPSEC */ 2874