1 /* $OpenBSD: ip6_input.c,v 1.226 2020/05/06 07:08:53 mpi Exp $ */ 2 /* $KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 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, 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_input.c 8.2 (Berkeley) 1/4/94 62 */ 63 64 #include "pf.h" 65 #include "carp.h" 66 67 #include <sys/param.h> 68 #include <sys/systm.h> 69 #include <sys/mbuf.h> 70 #include <sys/domain.h> 71 #include <sys/sysctl.h> 72 #include <sys/protosw.h> 73 #include <sys/socket.h> 74 #include <sys/socketvar.h> 75 #include <sys/errno.h> 76 #include <sys/time.h> 77 #include <sys/timeout.h> 78 #include <sys/kernel.h> 79 #include <sys/syslog.h> 80 #include <sys/task.h> 81 82 #include <net/if.h> 83 #include <net/if_var.h> 84 #include <net/if_types.h> 85 #include <net/route.h> 86 #include <net/netisr.h> 87 88 #include <netinet/in.h> 89 90 #include <netinet/ip.h> 91 92 #include <netinet/in_pcb.h> 93 #include <netinet/ip_var.h> 94 #include <netinet6/in6_var.h> 95 #include <netinet6/in6_ifattach.h> 96 #include <netinet/ip6.h> 97 #include <netinet6/ip6_var.h> 98 #include <netinet/icmp6.h> 99 #include <netinet6/nd6.h> 100 101 #include <netinet6/ip6protosw.h> 102 103 #include "gif.h" 104 #include "bpfilter.h" 105 106 #ifdef MROUTING 107 #include <netinet6/ip6_mroute.h> 108 #endif 109 110 #if NPF > 0 111 #include <net/pfvar.h> 112 #endif 113 114 #if NCARP > 0 115 #include <netinet/ip_carp.h> 116 #endif 117 118 struct cpumem *ip6counters; 119 120 uint8_t ip6_soiikey[IP6_SOIIKEY_LEN]; 121 122 int ip6_ours(struct mbuf **, int *, int, int); 123 int ip6_check_rh0hdr(struct mbuf *, int *); 124 int ip6_hbhchcheck(struct mbuf *, int *, int *, int *); 125 int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *); 126 struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int); 127 int ip6_sysctl_soiikey(void *, size_t *, void *, size_t); 128 129 static struct mbuf_queue ip6send_mq; 130 131 static void ip6_send_dispatch(void *); 132 static struct task ip6send_task = 133 TASK_INITIALIZER(ip6_send_dispatch, &ip6send_mq); 134 135 /* 136 * IP6 initialization: fill in IP6 protocol switch table. 137 * All protocols not implemented in kernel go to raw IP6 protocol handler. 138 */ 139 void 140 ip6_init(void) 141 { 142 const struct protosw *pr; 143 int i; 144 145 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 146 if (pr == NULL) 147 panic("%s", __func__); 148 for (i = 0; i < IPPROTO_MAX; i++) 149 ip6_protox[i] = pr - inet6sw; 150 for (pr = inet6domain.dom_protosw; 151 pr < inet6domain.dom_protoswNPROTOSW; pr++) 152 if (pr->pr_domain->dom_family == PF_INET6 && 153 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW && 154 pr->pr_protocol < IPPROTO_MAX) 155 ip6_protox[pr->pr_protocol] = pr - inet6sw; 156 ip6_randomid_init(); 157 nd6_init(); 158 frag6_init(); 159 160 mq_init(&ip6send_mq, 64, IPL_SOFTNET); 161 162 ip6counters = counters_alloc(ip6s_ncounters); 163 } 164 165 void 166 ipv6_input(struct ifnet *ifp, struct mbuf *m) 167 { 168 int off, nxt; 169 170 off = 0; 171 nxt = ip6_input_if(&m, &off, IPPROTO_IPV6, AF_UNSPEC, ifp); 172 KASSERT(nxt == IPPROTO_DONE); 173 } 174 175 int 176 ip6_input_if(struct mbuf **mp, int *offp, int nxt, int af, struct ifnet *ifp) 177 { 178 struct mbuf *m = *mp; 179 struct ip6_hdr *ip6; 180 struct sockaddr_in6 sin6; 181 struct rtentry *rt = NULL; 182 int ours = 0; 183 u_int16_t src_scope, dst_scope; 184 #if NPF > 0 185 struct in6_addr odst; 186 #endif 187 int srcrt = 0; 188 189 KASSERT(*offp == 0); 190 191 ip6stat_inc(ip6s_total); 192 193 if (m->m_len < sizeof(struct ip6_hdr)) { 194 if ((m = *mp = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 195 ip6stat_inc(ip6s_toosmall); 196 goto bad; 197 } 198 } 199 200 ip6 = mtod(m, struct ip6_hdr *); 201 202 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 203 ip6stat_inc(ip6s_badvers); 204 goto bad; 205 } 206 207 #if NCARP > 0 208 if (carp_lsdrop(ifp, m, AF_INET6, ip6->ip6_src.s6_addr32, 209 ip6->ip6_dst.s6_addr32, (ip6->ip6_nxt == IPPROTO_ICMPV6 ? 0 : 1))) 210 goto bad; 211 #endif 212 ip6stat_inc(ip6s_nxthist + ip6->ip6_nxt); 213 214 /* 215 * Check against address spoofing/corruption. 216 */ 217 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 218 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 219 /* 220 * XXX: "badscope" is not very suitable for a multicast source. 221 */ 222 ip6stat_inc(ip6s_badscope); 223 goto bad; 224 } 225 if ((IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 226 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) && 227 (ifp->if_flags & IFF_LOOPBACK) == 0) { 228 ip6stat_inc(ip6s_badscope); 229 goto bad; 230 } 231 /* Drop packets if interface ID portion is already filled. */ 232 if (((IN6_IS_SCOPE_EMBED(&ip6->ip6_src) && ip6->ip6_src.s6_addr16[1]) || 233 (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst) && ip6->ip6_dst.s6_addr16[1])) && 234 (ifp->if_flags & IFF_LOOPBACK) == 0) { 235 ip6stat_inc(ip6s_badscope); 236 goto bad; 237 } 238 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && 239 !(m->m_flags & M_LOOP)) { 240 /* 241 * In this case, the packet should come from the loopback 242 * interface. However, we cannot just check the if_flags, 243 * because ip6_mloopback() passes the "actual" interface 244 * as the outgoing/incoming interface. 245 */ 246 ip6stat_inc(ip6s_badscope); 247 goto bad; 248 } 249 250 /* 251 * The following check is not documented in specs. A malicious 252 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 253 * and bypass security checks (act as if it was from 127.0.0.1 by using 254 * IPv6 src ::ffff:127.0.0.1). Be cautious. 255 * 256 * This check chokes if we are in an SIIT cloud. As none of BSDs 257 * support IPv4-less kernel compilation, we cannot support SIIT 258 * environment at all. So, it makes more sense for us to reject any 259 * malicious packets for non-SIIT environment, than try to do a 260 * partial support for SIIT environment. 261 */ 262 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 263 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 264 ip6stat_inc(ip6s_badscope); 265 goto bad; 266 } 267 268 /* 269 * Reject packets with IPv4 compatible addresses (auto tunnel). 270 * 271 * The code forbids automatic tunneling as per RFC4213. 272 */ 273 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 274 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 275 ip6stat_inc(ip6s_badscope); 276 goto bad; 277 } 278 279 /* 280 * If the packet has been received on a loopback interface it 281 * can be destinated to any local address, not necessarily to 282 * an address configured on `ifp'. 283 */ 284 if (ifp->if_flags & IFF_LOOPBACK) { 285 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { 286 src_scope = ip6->ip6_src.s6_addr16[1]; 287 ip6->ip6_src.s6_addr16[1] = 0; 288 } 289 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { 290 dst_scope = ip6->ip6_dst.s6_addr16[1]; 291 ip6->ip6_dst.s6_addr16[1] = 0; 292 } 293 } 294 295 #if NPF > 0 296 /* 297 * Packet filter 298 */ 299 odst = ip6->ip6_dst; 300 if (pf_test(AF_INET6, PF_IN, ifp, mp) != PF_PASS) 301 goto bad; 302 m = *mp; 303 if (m == NULL) 304 goto bad; 305 306 ip6 = mtod(m, struct ip6_hdr *); 307 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 308 #endif 309 310 /* 311 * Without embedded scope ID we cannot find link-local 312 * addresses in the routing table. 313 */ 314 if (ifp->if_flags & IFF_LOOPBACK) { 315 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 316 ip6->ip6_src.s6_addr16[1] = src_scope; 317 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 318 ip6->ip6_dst.s6_addr16[1] = dst_scope; 319 } else { 320 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 321 ip6->ip6_src.s6_addr16[1] = htons(ifp->if_index); 322 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 323 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 324 } 325 326 /* 327 * Be more secure than RFC5095 and scan for type 0 routing headers. 328 * If pf has already scanned the header chain, do not do it twice. 329 */ 330 if (!(m->m_pkthdr.pf.flags & PF_TAG_PROCESSED) && 331 ip6_check_rh0hdr(m, offp)) { 332 ip6stat_inc(ip6s_badoptions); 333 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, *offp); 334 m = *mp = NULL; 335 goto bad; 336 } 337 338 #if NPF > 0 339 if (pf_ouraddr(m) == 1) { 340 nxt = ip6_ours(mp, offp, nxt, af); 341 goto out; 342 } 343 #endif 344 345 /* 346 * Multicast check 347 */ 348 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 349 /* 350 * Make sure M_MCAST is set. It should theoretically 351 * already be there, but let's play safe because upper 352 * layers check for this flag. 353 */ 354 m->m_flags |= M_MCAST; 355 356 /* 357 * See if we belong to the destination multicast group on the 358 * arrival interface. 359 */ 360 if (in6_hasmulti(&ip6->ip6_dst, ifp)) 361 ours = 1; 362 363 #ifdef MROUTING 364 if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain]) { 365 int error; 366 367 if (ip6_hbhchcheck(m, offp, &nxt, &ours)) 368 goto out; 369 370 ip6 = mtod(m, struct ip6_hdr *); 371 372 /* 373 * If we are acting as a multicast router, all 374 * incoming multicast packets are passed to the 375 * kernel-level multicast forwarding function. 376 * The packet is returned (relatively) intact; if 377 * ip6_mforward() returns a non-zero value, the packet 378 * must be discarded, else it may be accepted below. 379 */ 380 KERNEL_LOCK(); 381 error = ip6_mforward(ip6, ifp, m); 382 KERNEL_UNLOCK(); 383 if (error) { 384 ip6stat_inc(ip6s_cantforward); 385 goto bad; 386 } 387 388 if (ours) { 389 if (af == AF_UNSPEC) { 390 KERNEL_LOCK(); 391 nxt = ip_deliver(mp, offp, nxt, 392 AF_INET6); 393 KERNEL_UNLOCK(); 394 } 395 goto out; 396 } 397 goto bad; 398 } 399 #endif 400 if (!ours) { 401 ip6stat_inc(ip6s_notmember); 402 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 403 ip6stat_inc(ip6s_cantforward); 404 goto bad; 405 } 406 nxt = ip6_ours(mp, offp, nxt, af); 407 goto out; 408 } 409 410 411 /* 412 * Unicast check 413 */ 414 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 415 sin6.sin6_len = sizeof(struct sockaddr_in6); 416 sin6.sin6_family = AF_INET6; 417 sin6.sin6_addr = ip6->ip6_dst; 418 rt = rtalloc_mpath(sin6tosa(&sin6), &ip6->ip6_src.s6_addr32[0], 419 m->m_pkthdr.ph_rtableid); 420 421 /* 422 * Accept the packet if the route to the destination is marked 423 * as local. 424 */ 425 if (rtisvalid(rt) && ISSET(rt->rt_flags, RTF_LOCAL)) { 426 struct in6_ifaddr *ia6 = ifatoia6(rt->rt_ifa); 427 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 428 m->m_flags |= M_ACAST; 429 430 if (ip6_forwarding == 0 && rt->rt_ifidx != ifp->if_index && 431 !((ifp->if_flags & IFF_LOOPBACK) || 432 (ifp->if_type == IFT_ENC) || 433 (m->m_pkthdr.pf.flags & PF_TAG_TRANSLATE_LOCALHOST))) { 434 /* received on wrong interface */ 435 #if NCARP > 0 436 struct ifnet *out_if; 437 438 /* 439 * Virtual IPs on carp interfaces need to be checked 440 * also against the parent interface and other carp 441 * interfaces sharing the same parent. 442 */ 443 out_if = if_get(rt->rt_ifidx); 444 if (!(out_if && carp_strict_addr_chk(out_if, ifp))) { 445 ip6stat_inc(ip6s_wrongif); 446 if_put(out_if); 447 goto bad; 448 } 449 if_put(out_if); 450 #else 451 ip6stat_inc(ip6s_wrongif); 452 goto bad; 453 #endif 454 } 455 /* 456 * packets to a tentative, duplicated, or somehow invalid 457 * address must not be accepted. 458 */ 459 if ((ia6->ia6_flags & (IN6_IFF_TENTATIVE|IN6_IFF_DUPLICATED))) { 460 char src[INET6_ADDRSTRLEN], dst[INET6_ADDRSTRLEN]; 461 462 inet_ntop(AF_INET6, &ip6->ip6_src, src, sizeof(src)); 463 inet_ntop(AF_INET6, &ip6->ip6_dst, dst, sizeof(dst)); 464 /* address is not ready, so discard the packet. */ 465 nd6log((LOG_INFO, 466 "%s: packet to an unready address %s->%s\n", 467 __func__, src, dst)); 468 469 goto bad; 470 } else { 471 nxt = ip6_ours(mp, offp, nxt, af); 472 goto out; 473 } 474 } 475 476 #if NCARP > 0 477 if (ip6->ip6_nxt == IPPROTO_ICMPV6 && 478 carp_lsdrop(ifp, m, AF_INET6, ip6->ip6_src.s6_addr32, 479 ip6->ip6_dst.s6_addr32, 1)) 480 goto bad; 481 #endif 482 /* 483 * Now there is no reason to process the packet if it's not our own 484 * and we're not a router. 485 */ 486 if (!ip6_forwarding) { 487 ip6stat_inc(ip6s_cantforward); 488 goto bad; 489 } 490 491 if (ip6_hbhchcheck(m, offp, &nxt, &ours)) 492 goto out; 493 494 if (ours) { 495 if (af == AF_UNSPEC) { 496 KERNEL_LOCK(); 497 nxt = ip_deliver(mp, offp, nxt, AF_INET6); 498 KERNEL_UNLOCK(); 499 } 500 goto out; 501 } 502 503 #ifdef IPSEC 504 if (ipsec_in_use) { 505 int rv; 506 507 rv = ipsec_forward_check(m, *offp, AF_INET6); 508 if (rv != 0) { 509 ip6stat_inc(ip6s_cantforward); 510 goto bad; 511 } 512 /* 513 * Fall through, forward packet. Outbound IPsec policy 514 * checking will occur in ip6_forward(). 515 */ 516 } 517 #endif /* IPSEC */ 518 519 ip6_forward(m, rt, srcrt); 520 *mp = NULL; 521 return IPPROTO_DONE; 522 bad: 523 nxt = IPPROTO_DONE; 524 m_freemp(mp); 525 out: 526 rtfree(rt); 527 return nxt; 528 } 529 530 int 531 ip6_ours(struct mbuf **mp, int *offp, int nxt, int af) 532 { 533 if (ip6_hbhchcheck(*mp, offp, &nxt, NULL)) 534 return IPPROTO_DONE; 535 536 /* Check wheter we are already in a IPv4/IPv6 local deliver loop. */ 537 if (af == AF_UNSPEC) 538 nxt = ip_deliver(mp, offp, nxt, AF_INET6); 539 return nxt; 540 } 541 542 int 543 ip6_hbhchcheck(struct mbuf *m, int *offp, int *nxtp, int *oursp) 544 { 545 struct ip6_hdr *ip6; 546 u_int32_t plen, rtalert = ~0; 547 548 ip6 = mtod(m, struct ip6_hdr *); 549 550 /* 551 * Process Hop-by-Hop options header if it's contained. 552 * m may be modified in ip6_hopopts_input(). 553 * If a JumboPayload option is included, plen will also be modified. 554 */ 555 plen = (u_int32_t)ntohs(ip6->ip6_plen); 556 *offp = sizeof(struct ip6_hdr); 557 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 558 struct ip6_hbh *hbh; 559 560 if (ip6_hopopts_input(&plen, &rtalert, &m, offp)) { 561 goto bad; /* m have already been freed */ 562 } 563 564 /* adjust pointer */ 565 ip6 = mtod(m, struct ip6_hdr *); 566 567 /* 568 * if the payload length field is 0 and the next header field 569 * indicates Hop-by-Hop Options header, then a Jumbo Payload 570 * option MUST be included. 571 */ 572 if (ip6->ip6_plen == 0 && plen == 0) { 573 /* 574 * Note that if a valid jumbo payload option is 575 * contained, ip6_hopopts_input() must set a valid 576 * (non-zero) payload length to the variable plen. 577 */ 578 ip6stat_inc(ip6s_badoptions); 579 icmp6_error(m, ICMP6_PARAM_PROB, 580 ICMP6_PARAMPROB_HEADER, 581 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 582 goto bad; 583 } 584 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 585 sizeof(struct ip6_hbh)); 586 if (hbh == NULL) { 587 ip6stat_inc(ip6s_tooshort); 588 goto bad; 589 } 590 *nxtp = hbh->ip6h_nxt; 591 592 /* 593 * accept the packet if a router alert option is included 594 * and we act as an IPv6 router. 595 */ 596 if (rtalert != ~0 && ip6_forwarding && oursp != NULL) 597 *oursp = 1; 598 } else 599 *nxtp = ip6->ip6_nxt; 600 601 /* 602 * Check that the amount of data in the buffers 603 * is as at least much as the IPv6 header would have us expect. 604 * Trim mbufs if longer than we expect. 605 * Drop packet if shorter than we expect. 606 */ 607 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 608 ip6stat_inc(ip6s_tooshort); 609 m_freem(m); 610 goto bad; 611 } 612 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 613 if (m->m_len == m->m_pkthdr.len) { 614 m->m_len = sizeof(struct ip6_hdr) + plen; 615 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 616 } else { 617 m_adj(m, 618 sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 619 } 620 } 621 622 return (0); 623 624 bad: 625 *nxtp = IPPROTO_DONE; 626 return (-1); 627 } 628 629 /* scan packet for RH0 routing header. Mostly stolen from pf.c:pf_test() */ 630 int 631 ip6_check_rh0hdr(struct mbuf *m, int *offp) 632 { 633 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 634 struct ip6_rthdr rthdr; 635 struct ip6_ext opt6; 636 u_int8_t proto = ip6->ip6_nxt; 637 int done = 0, lim, off, rh_cnt = 0; 638 639 off = ((caddr_t)ip6 - m->m_data) + sizeof(struct ip6_hdr); 640 lim = min(m->m_pkthdr.len, ntohs(ip6->ip6_plen) + sizeof(*ip6)); 641 do { 642 switch (proto) { 643 case IPPROTO_ROUTING: 644 *offp = off; 645 if (rh_cnt++) { 646 /* more than one rh header present */ 647 return (1); 648 } 649 650 if (off + sizeof(rthdr) > lim) { 651 /* packet to short to make sense */ 652 return (1); 653 } 654 655 m_copydata(m, off, sizeof(rthdr), (caddr_t)&rthdr); 656 657 if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) { 658 *offp += offsetof(struct ip6_rthdr, ip6r_type); 659 return (1); 660 } 661 662 off += (rthdr.ip6r_len + 1) * 8; 663 proto = rthdr.ip6r_nxt; 664 break; 665 case IPPROTO_AH: 666 case IPPROTO_HOPOPTS: 667 case IPPROTO_DSTOPTS: 668 /* get next header and header length */ 669 if (off + sizeof(opt6) > lim) { 670 /* 671 * Packet to short to make sense, we could 672 * reject the packet but as a router we 673 * should not do that so forward it. 674 */ 675 return (0); 676 } 677 678 m_copydata(m, off, sizeof(opt6), (caddr_t)&opt6); 679 680 if (proto == IPPROTO_AH) 681 off += (opt6.ip6e_len + 2) * 4; 682 else 683 off += (opt6.ip6e_len + 1) * 8; 684 proto = opt6.ip6e_nxt; 685 break; 686 case IPPROTO_FRAGMENT: 687 default: 688 /* end of header stack */ 689 done = 1; 690 break; 691 } 692 } while (!done); 693 694 return (0); 695 } 696 697 /* 698 * Hop-by-Hop options header processing. If a valid jumbo payload option is 699 * included, the real payload length will be stored in plenp. 700 * 701 * rtalertp - XXX: should be stored in a more smart way 702 */ 703 int 704 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp, struct mbuf **mp, 705 int *offp) 706 { 707 struct mbuf *m = *mp; 708 int off = *offp, hbhlen; 709 struct ip6_hbh *hbh; 710 711 /* validation of the length of the header */ 712 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 713 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 714 if (hbh == NULL) { 715 ip6stat_inc(ip6s_tooshort); 716 return -1; 717 } 718 hbhlen = (hbh->ip6h_len + 1) << 3; 719 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 720 hbhlen); 721 if (hbh == NULL) { 722 ip6stat_inc(ip6s_tooshort); 723 return -1; 724 } 725 off += hbhlen; 726 hbhlen -= sizeof(struct ip6_hbh); 727 728 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 729 hbhlen, rtalertp, plenp) < 0) 730 return (-1); 731 732 *offp = off; 733 *mp = m; 734 return (0); 735 } 736 737 /* 738 * Search header for all Hop-by-hop options and process each option. 739 * This function is separate from ip6_hopopts_input() in order to 740 * handle a case where the sending node itself process its hop-by-hop 741 * options header. In such a case, the function is called from ip6_output(). 742 * 743 * The function assumes that hbh header is located right after the IPv6 header 744 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 745 * opthead + hbhlen is located in continuous memory region. 746 */ 747 int 748 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 749 u_int32_t *rtalertp, u_int32_t *plenp) 750 { 751 struct ip6_hdr *ip6; 752 int optlen = 0; 753 u_int8_t *opt = opthead; 754 u_int16_t rtalert_val; 755 u_int32_t jumboplen; 756 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 757 758 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 759 switch (*opt) { 760 case IP6OPT_PAD1: 761 optlen = 1; 762 break; 763 case IP6OPT_PADN: 764 if (hbhlen < IP6OPT_MINLEN) { 765 ip6stat_inc(ip6s_toosmall); 766 goto bad; 767 } 768 optlen = *(opt + 1) + 2; 769 break; 770 case IP6OPT_ROUTER_ALERT: 771 /* XXX may need check for alignment */ 772 if (hbhlen < IP6OPT_RTALERT_LEN) { 773 ip6stat_inc(ip6s_toosmall); 774 goto bad; 775 } 776 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 777 /* XXX stat */ 778 icmp6_error(m, ICMP6_PARAM_PROB, 779 ICMP6_PARAMPROB_HEADER, 780 erroff + opt + 1 - opthead); 781 return (-1); 782 } 783 optlen = IP6OPT_RTALERT_LEN; 784 memcpy((caddr_t)&rtalert_val, (caddr_t)(opt + 2), 2); 785 *rtalertp = ntohs(rtalert_val); 786 break; 787 case IP6OPT_JUMBO: 788 /* XXX may need check for alignment */ 789 if (hbhlen < IP6OPT_JUMBO_LEN) { 790 ip6stat_inc(ip6s_toosmall); 791 goto bad; 792 } 793 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 794 /* XXX stat */ 795 icmp6_error(m, ICMP6_PARAM_PROB, 796 ICMP6_PARAMPROB_HEADER, 797 erroff + opt + 1 - opthead); 798 return (-1); 799 } 800 optlen = IP6OPT_JUMBO_LEN; 801 802 /* 803 * IPv6 packets that have non 0 payload length 804 * must not contain a jumbo payload option. 805 */ 806 ip6 = mtod(m, struct ip6_hdr *); 807 if (ip6->ip6_plen) { 808 ip6stat_inc(ip6s_badoptions); 809 icmp6_error(m, ICMP6_PARAM_PROB, 810 ICMP6_PARAMPROB_HEADER, 811 erroff + opt - opthead); 812 return (-1); 813 } 814 815 /* 816 * We may see jumbolen in unaligned location, so 817 * we'd need to perform memcpy(). 818 */ 819 memcpy(&jumboplen, opt + 2, sizeof(jumboplen)); 820 jumboplen = (u_int32_t)htonl(jumboplen); 821 822 #if 1 823 /* 824 * if there are multiple jumbo payload options, 825 * *plenp will be non-zero and the packet will be 826 * rejected. 827 * the behavior may need some debate in ipngwg - 828 * multiple options does not make sense, however, 829 * there's no explicit mention in specification. 830 */ 831 if (*plenp != 0) { 832 ip6stat_inc(ip6s_badoptions); 833 icmp6_error(m, ICMP6_PARAM_PROB, 834 ICMP6_PARAMPROB_HEADER, 835 erroff + opt + 2 - opthead); 836 return (-1); 837 } 838 #endif 839 840 /* 841 * jumbo payload length must be larger than 65535. 842 */ 843 if (jumboplen <= IPV6_MAXPACKET) { 844 ip6stat_inc(ip6s_badoptions); 845 icmp6_error(m, ICMP6_PARAM_PROB, 846 ICMP6_PARAMPROB_HEADER, 847 erroff + opt + 2 - opthead); 848 return (-1); 849 } 850 *plenp = jumboplen; 851 852 break; 853 default: /* unknown option */ 854 if (hbhlen < IP6OPT_MINLEN) { 855 ip6stat_inc(ip6s_toosmall); 856 goto bad; 857 } 858 optlen = ip6_unknown_opt(opt, m, 859 erroff + opt - opthead); 860 if (optlen == -1) 861 return (-1); 862 optlen += 2; 863 break; 864 } 865 } 866 867 return (0); 868 869 bad: 870 m_freem(m); 871 return (-1); 872 } 873 874 /* 875 * Unknown option processing. 876 * The third argument `off' is the offset from the IPv6 header to the option, 877 * which allows returning an ICMPv6 error even if the IPv6 header and the 878 * option header are not continuous. 879 */ 880 int 881 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 882 { 883 struct ip6_hdr *ip6; 884 885 switch (IP6OPT_TYPE(*optp)) { 886 case IP6OPT_TYPE_SKIP: /* ignore the option */ 887 return ((int)*(optp + 1)); 888 case IP6OPT_TYPE_DISCARD: /* silently discard */ 889 m_freem(m); 890 return (-1); 891 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 892 ip6stat_inc(ip6s_badoptions); 893 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 894 return (-1); 895 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 896 ip6stat_inc(ip6s_badoptions); 897 ip6 = mtod(m, struct ip6_hdr *); 898 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 899 (m->m_flags & (M_BCAST|M_MCAST))) 900 m_freem(m); 901 else 902 icmp6_error(m, ICMP6_PARAM_PROB, 903 ICMP6_PARAMPROB_OPTION, off); 904 return (-1); 905 } 906 907 m_freem(m); /* XXX: NOTREACHED */ 908 return (-1); 909 } 910 911 /* 912 * Create the "control" list for this pcb. 913 * 914 * The routine will be called from upper layer handlers like udp_input(). 915 * Thus the routine assumes that the caller (udp_input) have already 916 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 917 * very first mbuf on the mbuf chain. 918 * We may want to add some infinite loop prevention or sanity checks for safety. 919 * (This applies only when you are using KAME mbuf chain restriction, i.e. 920 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 921 */ 922 void 923 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 924 { 925 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 926 927 if (in6p->inp_socket->so_options & SO_TIMESTAMP) { 928 struct timeval tv; 929 930 m_microtime(m, &tv); 931 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 932 SCM_TIMESTAMP, SOL_SOCKET); 933 if (*mp) 934 mp = &(*mp)->m_next; 935 } 936 937 /* RFC 2292 sec. 5 */ 938 if ((in6p->inp_flags & IN6P_PKTINFO) != 0) { 939 struct in6_pktinfo pi6; 940 memcpy(&pi6.ipi6_addr, &ip6->ip6_dst, sizeof(struct in6_addr)); 941 if (IN6_IS_SCOPE_EMBED(&pi6.ipi6_addr)) 942 pi6.ipi6_addr.s6_addr16[1] = 0; 943 pi6.ipi6_ifindex = m ? m->m_pkthdr.ph_ifidx : 0; 944 *mp = sbcreatecontrol((caddr_t) &pi6, 945 sizeof(struct in6_pktinfo), 946 IPV6_PKTINFO, IPPROTO_IPV6); 947 if (*mp) 948 mp = &(*mp)->m_next; 949 } 950 951 if ((in6p->inp_flags & IN6P_HOPLIMIT) != 0) { 952 int hlim = ip6->ip6_hlim & 0xff; 953 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 954 IPV6_HOPLIMIT, IPPROTO_IPV6); 955 if (*mp) 956 mp = &(*mp)->m_next; 957 } 958 959 if ((in6p->inp_flags & IN6P_TCLASS) != 0) { 960 u_int32_t flowinfo; 961 int tclass; 962 963 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 964 flowinfo >>= 20; 965 966 tclass = flowinfo & 0xff; 967 *mp = sbcreatecontrol((caddr_t)&tclass, sizeof(tclass), 968 IPV6_TCLASS, IPPROTO_IPV6); 969 if (*mp) 970 mp = &(*mp)->m_next; 971 } 972 973 /* 974 * IPV6_HOPOPTS socket option. Recall that we required super-user 975 * privilege for the option (see ip6_ctloutput), but it might be too 976 * strict, since there might be some hop-by-hop options which can be 977 * returned to normal user. 978 * See also RFC 2292 section 6 (or RFC 3542 section 8). 979 */ 980 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 981 /* 982 * Check if a hop-by-hop options header is contained in the 983 * received packet, and if so, store the options as ancillary 984 * data. Note that a hop-by-hop options header must be 985 * just after the IPv6 header, which is assured through the 986 * IPv6 input processing. 987 */ 988 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 989 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 990 struct ip6_hbh *hbh; 991 int hbhlen = 0; 992 struct mbuf *ext; 993 994 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 995 ip6->ip6_nxt); 996 if (ext == NULL) { 997 ip6stat_inc(ip6s_tooshort); 998 return; 999 } 1000 hbh = mtod(ext, struct ip6_hbh *); 1001 hbhlen = (hbh->ip6h_len + 1) << 3; 1002 if (hbhlen != ext->m_len) { 1003 m_freem(ext); 1004 ip6stat_inc(ip6s_tooshort); 1005 return; 1006 } 1007 1008 /* 1009 * XXX: We copy the whole header even if a 1010 * jumbo payload option is included, the option which 1011 * is to be removed before returning according to 1012 * RFC2292. 1013 * Note: this constraint is removed in RFC3542. 1014 */ 1015 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1016 IPV6_HOPOPTS, 1017 IPPROTO_IPV6); 1018 if (*mp) 1019 mp = &(*mp)->m_next; 1020 m_freem(ext); 1021 } 1022 } 1023 1024 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1025 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1026 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1027 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1028 1029 /* 1030 * Search for destination options headers or routing 1031 * header(s) through the header chain, and stores each 1032 * header as ancillary data. 1033 * Note that the order of the headers remains in 1034 * the chain of ancillary data. 1035 */ 1036 while (1) { /* is explicit loop prevention necessary? */ 1037 struct ip6_ext *ip6e = NULL; 1038 int elen; 1039 struct mbuf *ext = NULL; 1040 1041 /* 1042 * if it is not an extension header, don't try to 1043 * pull it from the chain. 1044 */ 1045 switch (nxt) { 1046 case IPPROTO_DSTOPTS: 1047 case IPPROTO_ROUTING: 1048 case IPPROTO_HOPOPTS: 1049 case IPPROTO_AH: /* is it possible? */ 1050 break; 1051 default: 1052 goto loopend; 1053 } 1054 1055 ext = ip6_pullexthdr(m, off, nxt); 1056 if (ext == NULL) { 1057 ip6stat_inc(ip6s_tooshort); 1058 return; 1059 } 1060 ip6e = mtod(ext, struct ip6_ext *); 1061 if (nxt == IPPROTO_AH) 1062 elen = (ip6e->ip6e_len + 2) << 2; 1063 else 1064 elen = (ip6e->ip6e_len + 1) << 3; 1065 if (elen != ext->m_len) { 1066 m_freem(ext); 1067 ip6stat_inc(ip6s_tooshort); 1068 return; 1069 } 1070 1071 switch (nxt) { 1072 case IPPROTO_DSTOPTS: 1073 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1074 break; 1075 1076 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1077 IPV6_DSTOPTS, 1078 IPPROTO_IPV6); 1079 if (*mp) 1080 mp = &(*mp)->m_next; 1081 break; 1082 1083 case IPPROTO_ROUTING: 1084 if (!(in6p->inp_flags & IN6P_RTHDR)) 1085 break; 1086 1087 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1088 IPV6_RTHDR, 1089 IPPROTO_IPV6); 1090 if (*mp) 1091 mp = &(*mp)->m_next; 1092 break; 1093 1094 case IPPROTO_HOPOPTS: 1095 case IPPROTO_AH: /* is it possible? */ 1096 break; 1097 1098 default: 1099 /* 1100 * other cases have been filtered in the above. 1101 * none will visit this case. here we supply 1102 * the code just in case (nxt overwritten or 1103 * other cases). 1104 */ 1105 m_freem(ext); 1106 goto loopend; 1107 1108 } 1109 1110 /* proceed with the next header. */ 1111 off += elen; 1112 nxt = ip6e->ip6e_nxt; 1113 ip6e = NULL; 1114 m_freem(ext); 1115 ext = NULL; 1116 } 1117 loopend: 1118 ; 1119 } 1120 } 1121 1122 /* 1123 * pull single extension header from mbuf chain. returns single mbuf that 1124 * contains the result, or NULL on error. 1125 */ 1126 struct mbuf * 1127 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1128 { 1129 struct ip6_ext ip6e; 1130 size_t elen; 1131 struct mbuf *n; 1132 1133 #ifdef DIAGNOSTIC 1134 switch (nxt) { 1135 case IPPROTO_DSTOPTS: 1136 case IPPROTO_ROUTING: 1137 case IPPROTO_HOPOPTS: 1138 case IPPROTO_AH: /* is it possible? */ 1139 break; 1140 default: 1141 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1142 } 1143 #endif 1144 1145 if (off + sizeof(ip6e) > m->m_pkthdr.len) 1146 return NULL; 1147 1148 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1149 if (nxt == IPPROTO_AH) 1150 elen = (ip6e.ip6e_len + 2) << 2; 1151 else 1152 elen = (ip6e.ip6e_len + 1) << 3; 1153 1154 if (off + elen > m->m_pkthdr.len) 1155 return NULL; 1156 1157 MGET(n, M_DONTWAIT, MT_DATA); 1158 if (n && elen >= MLEN) { 1159 MCLGET(n, M_DONTWAIT); 1160 if ((n->m_flags & M_EXT) == 0) { 1161 m_free(n); 1162 n = NULL; 1163 } 1164 } 1165 if (!n) 1166 return NULL; 1167 1168 n->m_len = 0; 1169 if (elen >= m_trailingspace(n)) { 1170 m_free(n); 1171 return NULL; 1172 } 1173 1174 m_copydata(m, off, elen, mtod(n, caddr_t)); 1175 n->m_len = elen; 1176 return n; 1177 } 1178 1179 /* 1180 * Get offset to the previous header followed by the header 1181 * currently processed. 1182 */ 1183 int 1184 ip6_get_prevhdr(struct mbuf *m, int off) 1185 { 1186 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1187 1188 if (off == sizeof(struct ip6_hdr)) { 1189 return offsetof(struct ip6_hdr, ip6_nxt); 1190 } else if (off < sizeof(struct ip6_hdr)) { 1191 panic("%s: off < sizeof(struct ip6_hdr)", __func__); 1192 } else { 1193 int len, nlen, nxt; 1194 struct ip6_ext ip6e; 1195 1196 nxt = ip6->ip6_nxt; 1197 len = sizeof(struct ip6_hdr); 1198 nlen = 0; 1199 while (len < off) { 1200 m_copydata(m, len, sizeof(ip6e), (caddr_t)&ip6e); 1201 1202 switch (nxt) { 1203 case IPPROTO_FRAGMENT: 1204 nlen = sizeof(struct ip6_frag); 1205 break; 1206 case IPPROTO_AH: 1207 nlen = (ip6e.ip6e_len + 2) << 2; 1208 break; 1209 default: 1210 nlen = (ip6e.ip6e_len + 1) << 3; 1211 break; 1212 } 1213 len += nlen; 1214 nxt = ip6e.ip6e_nxt; 1215 } 1216 1217 return (len - nlen); 1218 } 1219 } 1220 1221 /* 1222 * get next header offset. m will be retained. 1223 */ 1224 int 1225 ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp) 1226 { 1227 struct ip6_hdr ip6; 1228 struct ip6_ext ip6e; 1229 struct ip6_frag fh; 1230 1231 /* just in case */ 1232 if (m == NULL) 1233 panic("%s: m == NULL", __func__); 1234 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1235 return -1; 1236 1237 switch (proto) { 1238 case IPPROTO_IPV6: 1239 if (m->m_pkthdr.len < off + sizeof(ip6)) 1240 return -1; 1241 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1242 if (nxtp) 1243 *nxtp = ip6.ip6_nxt; 1244 off += sizeof(ip6); 1245 return off; 1246 1247 case IPPROTO_FRAGMENT: 1248 /* 1249 * terminate parsing if it is not the first fragment, 1250 * it does not make sense to parse through it. 1251 */ 1252 if (m->m_pkthdr.len < off + sizeof(fh)) 1253 return -1; 1254 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1255 if ((fh.ip6f_offlg & IP6F_OFF_MASK) != 0) 1256 return -1; 1257 if (nxtp) 1258 *nxtp = fh.ip6f_nxt; 1259 off += sizeof(struct ip6_frag); 1260 return off; 1261 1262 case IPPROTO_AH: 1263 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1264 return -1; 1265 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1266 if (nxtp) 1267 *nxtp = ip6e.ip6e_nxt; 1268 off += (ip6e.ip6e_len + 2) << 2; 1269 if (m->m_pkthdr.len < off) 1270 return -1; 1271 return off; 1272 1273 case IPPROTO_HOPOPTS: 1274 case IPPROTO_ROUTING: 1275 case IPPROTO_DSTOPTS: 1276 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1277 return -1; 1278 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1279 if (nxtp) 1280 *nxtp = ip6e.ip6e_nxt; 1281 off += (ip6e.ip6e_len + 1) << 3; 1282 if (m->m_pkthdr.len < off) 1283 return -1; 1284 return off; 1285 1286 case IPPROTO_NONE: 1287 case IPPROTO_ESP: 1288 case IPPROTO_IPCOMP: 1289 /* give up */ 1290 return -1; 1291 1292 default: 1293 return -1; 1294 } 1295 1296 return -1; 1297 } 1298 1299 /* 1300 * get offset for the last header in the chain. m will be kept untainted. 1301 */ 1302 int 1303 ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp) 1304 { 1305 int newoff; 1306 int nxt; 1307 1308 if (!nxtp) { 1309 nxt = -1; 1310 nxtp = &nxt; 1311 } 1312 while (1) { 1313 newoff = ip6_nexthdr(m, off, proto, nxtp); 1314 if (newoff < 0) 1315 return off; 1316 else if (newoff < off) 1317 return -1; /* invalid */ 1318 else if (newoff == off) 1319 return newoff; 1320 1321 off = newoff; 1322 proto = *nxtp; 1323 } 1324 } 1325 1326 /* 1327 * System control for IP6 1328 */ 1329 1330 const u_char inet6ctlerrmap[PRC_NCMDS] = { 1331 0, 0, 0, 0, 1332 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1333 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1334 EMSGSIZE, EHOSTUNREACH, 0, 0, 1335 0, 0, 0, 0, 1336 ENOPROTOOPT 1337 }; 1338 1339 int *ipv6ctl_vars[IPV6CTL_MAXID] = IPV6CTL_VARS; 1340 1341 int 1342 ip6_sysctl_ip6stat(void *oldp, size_t *oldlenp, void *newp) 1343 { 1344 struct ip6stat *ip6stat; 1345 int ret; 1346 1347 CTASSERT(sizeof(*ip6stat) == (ip6s_ncounters * sizeof(uint64_t))); 1348 1349 ip6stat = malloc(sizeof(*ip6stat), M_TEMP, M_WAITOK); 1350 counters_read(ip6counters, (uint64_t *)ip6stat, ip6s_ncounters); 1351 ret = sysctl_rdstruct(oldp, oldlenp, newp, 1352 ip6stat, sizeof(*ip6stat)); 1353 free(ip6stat, M_TEMP, sizeof(*ip6stat)); 1354 1355 return (ret); 1356 } 1357 1358 int 1359 ip6_sysctl_soiikey(void *oldp, size_t *oldlenp, void *newp, size_t newlen) 1360 { 1361 uint8_t oldkey[IP6_SOIIKEY_LEN]; 1362 int error; 1363 1364 error = suser(curproc); 1365 if (error != 0) 1366 return (error); 1367 1368 memcpy(oldkey, ip6_soiikey, sizeof(oldkey)); 1369 1370 error = sysctl_struct(oldp, oldlenp, newp, newlen, ip6_soiikey, 1371 sizeof(ip6_soiikey)); 1372 1373 return (error); 1374 } 1375 1376 int 1377 ip6_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, 1378 void *newp, size_t newlen) 1379 { 1380 #ifdef MROUTING 1381 extern int ip6_mrtproto; 1382 extern struct mrt6stat mrt6stat; 1383 #endif 1384 int error; 1385 1386 /* Almost all sysctl names at this level are terminal. */ 1387 if (namelen != 1 && name[0] != IPV6CTL_IFQUEUE) 1388 return (ENOTDIR); 1389 1390 switch (name[0]) { 1391 case IPV6CTL_DAD_PENDING: 1392 return sysctl_rdint(oldp, oldlenp, newp, ip6_dad_pending); 1393 case IPV6CTL_STATS: 1394 return (ip6_sysctl_ip6stat(oldp, oldlenp, newp)); 1395 #ifdef MROUTING 1396 case IPV6CTL_MRTSTATS: 1397 if (newp != NULL) 1398 return (EPERM); 1399 NET_LOCK(); 1400 error = sysctl_struct(oldp, oldlenp, newp, newlen, 1401 &mrt6stat, sizeof(mrt6stat)); 1402 NET_UNLOCK(); 1403 return (error); 1404 case IPV6CTL_MRTPROTO: 1405 return sysctl_rdint(oldp, oldlenp, newp, ip6_mrtproto); 1406 case IPV6CTL_MRTMIF: 1407 if (newp) 1408 return (EPERM); 1409 NET_LOCK(); 1410 error = mrt6_sysctl_mif(oldp, oldlenp); 1411 NET_UNLOCK(); 1412 return (error); 1413 case IPV6CTL_MRTMFC: 1414 if (newp) 1415 return (EPERM); 1416 NET_LOCK(); 1417 error = mrt6_sysctl_mfc(oldp, oldlenp); 1418 NET_UNLOCK(); 1419 return (error); 1420 #else 1421 case IPV6CTL_MRTSTATS: 1422 case IPV6CTL_MRTPROTO: 1423 case IPV6CTL_MRTMIF: 1424 case IPV6CTL_MRTMFC: 1425 return (EOPNOTSUPP); 1426 #endif 1427 case IPV6CTL_MTUDISCTIMEOUT: 1428 NET_LOCK(); 1429 error = sysctl_int(oldp, oldlenp, newp, newlen, 1430 &ip6_mtudisc_timeout); 1431 if (icmp6_mtudisc_timeout_q != NULL) 1432 rt_timer_queue_change(icmp6_mtudisc_timeout_q, 1433 ip6_mtudisc_timeout); 1434 NET_UNLOCK(); 1435 return (error); 1436 case IPV6CTL_IFQUEUE: 1437 return (EOPNOTSUPP); 1438 case IPV6CTL_SOIIKEY: 1439 return (ip6_sysctl_soiikey(oldp, oldlenp, newp, newlen)); 1440 default: 1441 if (name[0] < IPV6CTL_MAXID) { 1442 NET_LOCK(); 1443 error = sysctl_int_arr(ipv6ctl_vars, name, namelen, 1444 oldp, oldlenp, newp, newlen); 1445 NET_UNLOCK(); 1446 return (error); 1447 } 1448 return (EOPNOTSUPP); 1449 } 1450 /* NOTREACHED */ 1451 } 1452 1453 void 1454 ip6_send_dispatch(void *xmq) 1455 { 1456 struct mbuf_queue *mq = xmq; 1457 struct mbuf *m; 1458 struct mbuf_list ml; 1459 1460 mq_delist(mq, &ml); 1461 if (ml_empty(&ml)) 1462 return; 1463 1464 NET_LOCK(); 1465 while ((m = ml_dequeue(&ml)) != NULL) { 1466 /* 1467 * To avoid a "too big" situation at an intermediate router and 1468 * the path MTU discovery process, specify the IPV6_MINMTU 1469 * flag. Note that only echo and node information replies are 1470 * affected, since the length of ICMP6 errors is limited to the 1471 * minimum MTU. 1472 */ 1473 ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL); 1474 } 1475 NET_UNLOCK(); 1476 } 1477 1478 void 1479 ip6_send(struct mbuf *m) 1480 { 1481 mq_enqueue(&ip6send_mq, m); 1482 task_add(net_tq(0), &ip6send_task); 1483 } 1484