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sys/netinet6/ip6_input.c
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1 /* $OpenBSD: ip6_input.c,v 1.254 2022/08/21 14:15:55 bluhm 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 "gif.h" 102 #include "bpfilter.h" 103 104 #ifdef MROUTING 105 #include <netinet6/ip6_mroute.h> 106 #endif 107 108 #if NPF > 0 109 #include <net/pfvar.h> 110 #endif 111 112 #if NCARP > 0 113 #include <netinet/ip_carp.h> 114 #endif 115 116 struct niqueue ip6intrq = NIQUEUE_INITIALIZER(IPQ_MAXLEN, NETISR_IPV6); 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 *); 125 int ip6_hopopts_input(struct mbuf **, int *, u_int32_t *, u_int32_t *); 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 #ifdef MROUTING 164 rt_timer_queue_init(&ip6_mrouterq, MCAST_EXPIRE_TIMEOUT, 165 &mf6c_expire_route); 166 #endif 167 } 168 169 struct ip6_offnxt { 170 int ion_off; 171 int ion_nxt; 172 }; 173 174 /* 175 * Enqueue packet for local delivery. Queuing is used as a boundary 176 * between the network layer (input/forward path) running with 177 * NET_LOCK_SHARED() and the transport layer needing it exclusively. 178 */ 179 int 180 ip6_ours(struct mbuf **mp, int *offp, int nxt, int af) 181 { 182 /* ip6_hbhchcheck() may be run before, then off and nxt are set */ 183 if (*offp == 0) { 184 nxt = ip6_hbhchcheck(mp, offp, NULL); 185 if (nxt == IPPROTO_DONE) 186 return IPPROTO_DONE; 187 } 188 189 /* We are already in a IPv4/IPv6 local deliver loop. */ 190 if (af != AF_UNSPEC) 191 return nxt; 192 193 /* save values for later, use after dequeue */ 194 if (*offp != sizeof(struct ip6_hdr)) { 195 struct m_tag *mtag; 196 struct ip6_offnxt *ion; 197 198 /* mbuf tags are expensive, but only used for header options */ 199 mtag = m_tag_get(PACKET_TAG_IP6_OFFNXT, sizeof(*ion), 200 M_NOWAIT); 201 if (mtag == NULL) { 202 ip6stat_inc(ip6s_idropped); 203 m_freemp(mp); 204 return IPPROTO_DONE; 205 } 206 ion = (struct ip6_offnxt *)(mtag + 1); 207 ion->ion_off = *offp; 208 ion->ion_nxt = nxt; 209 210 m_tag_prepend(*mp, mtag); 211 } 212 213 niq_enqueue(&ip6intrq, *mp); 214 *mp = NULL; 215 return IPPROTO_DONE; 216 } 217 218 /* 219 * Dequeue and process locally delivered packets. 220 * This is called with exclusive NET_LOCK(). 221 */ 222 void 223 ip6intr(void) 224 { 225 struct mbuf *m; 226 227 while ((m = niq_dequeue(&ip6intrq)) != NULL) { 228 struct m_tag *mtag; 229 int off, nxt; 230 231 #ifdef DIAGNOSTIC 232 if ((m->m_flags & M_PKTHDR) == 0) 233 panic("ip6intr no HDR"); 234 #endif 235 mtag = m_tag_find(m, PACKET_TAG_IP6_OFFNXT, NULL); 236 if (mtag != NULL) { 237 struct ip6_offnxt *ion; 238 239 ion = (struct ip6_offnxt *)(mtag + 1); 240 off = ion->ion_off; 241 nxt = ion->ion_nxt; 242 243 m_tag_delete(m, mtag); 244 } else { 245 struct ip6_hdr *ip6; 246 247 ip6 = mtod(m, struct ip6_hdr *); 248 off = sizeof(struct ip6_hdr); 249 nxt = ip6->ip6_nxt; 250 } 251 nxt = ip_deliver(&m, &off, nxt, AF_INET6); 252 KASSERT(nxt == IPPROTO_DONE); 253 } 254 } 255 256 void 257 ipv6_input(struct ifnet *ifp, struct mbuf *m) 258 { 259 int off, nxt; 260 261 off = 0; 262 nxt = ip6_input_if(&m, &off, IPPROTO_IPV6, AF_UNSPEC, ifp); 263 KASSERT(nxt == IPPROTO_DONE); 264 } 265 266 struct mbuf * 267 ipv6_check(struct ifnet *ifp, struct mbuf *m) 268 { 269 struct ip6_hdr *ip6; 270 271 if (m->m_len < sizeof(*ip6)) { 272 m = m_pullup(m, sizeof(*ip6)); 273 if (m == NULL) { 274 ip6stat_inc(ip6s_toosmall); 275 return (NULL); 276 } 277 } 278 279 ip6 = mtod(m, struct ip6_hdr *); 280 281 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 282 ip6stat_inc(ip6s_badvers); 283 goto bad; 284 } 285 286 /* 287 * Check against address spoofing/corruption. 288 */ 289 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 290 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 291 /* 292 * XXX: "badscope" is not very suitable for a multicast source. 293 */ 294 ip6stat_inc(ip6s_badscope); 295 goto bad; 296 } 297 if ((IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 298 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) && 299 (ifp->if_flags & IFF_LOOPBACK) == 0) { 300 ip6stat_inc(ip6s_badscope); 301 goto bad; 302 } 303 /* Drop packets if interface ID portion is already filled. */ 304 if (((IN6_IS_SCOPE_EMBED(&ip6->ip6_src) && ip6->ip6_src.s6_addr16[1]) || 305 (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst) && ip6->ip6_dst.s6_addr16[1])) && 306 (ifp->if_flags & IFF_LOOPBACK) == 0) { 307 ip6stat_inc(ip6s_badscope); 308 goto bad; 309 } 310 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && 311 !(m->m_flags & M_LOOP)) { 312 /* 313 * In this case, the packet should come from the loopback 314 * interface. However, we cannot just check the if_flags, 315 * because ip6_mloopback() passes the "actual" interface 316 * as the outgoing/incoming interface. 317 */ 318 ip6stat_inc(ip6s_badscope); 319 goto bad; 320 } 321 322 /* 323 * The following check is not documented in specs. A malicious 324 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 325 * and bypass security checks (act as if it was from 127.0.0.1 by using 326 * IPv6 src ::ffff:127.0.0.1). Be cautious. 327 * 328 * This check chokes if we are in an SIIT cloud. As none of BSDs 329 * support IPv4-less kernel compilation, we cannot support SIIT 330 * environment at all. So, it makes more sense for us to reject any 331 * malicious packets for non-SIIT environment, than try to do a 332 * partial support for SIIT environment. 333 */ 334 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 335 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 336 ip6stat_inc(ip6s_badscope); 337 goto bad; 338 } 339 340 /* 341 * Reject packets with IPv4 compatible addresses (auto tunnel). 342 * 343 * The code forbids automatic tunneling as per RFC4213. 344 */ 345 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 346 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 347 ip6stat_inc(ip6s_badscope); 348 goto bad; 349 } 350 351 return (m); 352 bad: 353 m_freem(m); 354 return (NULL); 355 } 356 357 int 358 ip6_input_if(struct mbuf **mp, int *offp, int nxt, int af, struct ifnet *ifp) 359 { 360 struct mbuf *m; 361 struct ip6_hdr *ip6; 362 struct sockaddr_in6 sin6; 363 struct rtentry *rt = NULL; 364 int ours = 0; 365 u_int16_t src_scope, dst_scope; 366 #if NPF > 0 367 struct in6_addr odst; 368 #endif 369 int srcrt = 0; 370 371 KASSERT(*offp == 0); 372 373 ip6stat_inc(ip6s_total); 374 375 m = *mp = ipv6_check(ifp, *mp); 376 if (m == NULL) 377 goto bad; 378 379 ip6 = mtod(m, struct ip6_hdr *); 380 381 #if NCARP > 0 382 if (carp_lsdrop(ifp, m, AF_INET6, ip6->ip6_src.s6_addr32, 383 ip6->ip6_dst.s6_addr32, (ip6->ip6_nxt == IPPROTO_ICMPV6 ? 0 : 1))) 384 goto bad; 385 #endif 386 ip6stat_inc(ip6s_nxthist + ip6->ip6_nxt); 387 388 /* 389 * If the packet has been received on a loopback interface it 390 * can be destined to any local address, not necessarily to 391 * an address configured on `ifp'. 392 */ 393 if (ifp->if_flags & IFF_LOOPBACK) { 394 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { 395 src_scope = ip6->ip6_src.s6_addr16[1]; 396 ip6->ip6_src.s6_addr16[1] = 0; 397 } 398 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { 399 dst_scope = ip6->ip6_dst.s6_addr16[1]; 400 ip6->ip6_dst.s6_addr16[1] = 0; 401 } 402 } 403 404 #if NPF > 0 405 /* 406 * Packet filter 407 */ 408 odst = ip6->ip6_dst; 409 if (pf_test(AF_INET6, PF_IN, ifp, mp) != PF_PASS) 410 goto bad; 411 m = *mp; 412 if (m == NULL) 413 goto bad; 414 415 ip6 = mtod(m, struct ip6_hdr *); 416 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 417 #endif 418 419 /* 420 * Without embedded scope ID we cannot find link-local 421 * addresses in the routing table. 422 */ 423 if (ifp->if_flags & IFF_LOOPBACK) { 424 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 425 ip6->ip6_src.s6_addr16[1] = src_scope; 426 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 427 ip6->ip6_dst.s6_addr16[1] = dst_scope; 428 } else { 429 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) 430 ip6->ip6_src.s6_addr16[1] = htons(ifp->if_index); 431 if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) 432 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 433 } 434 435 /* 436 * Be more secure than RFC5095 and scan for type 0 routing headers. 437 * If pf has already scanned the header chain, do not do it twice. 438 */ 439 if (!(m->m_pkthdr.pf.flags & PF_TAG_PROCESSED) && 440 ip6_check_rh0hdr(m, offp)) { 441 ip6stat_inc(ip6s_badoptions); 442 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, *offp); 443 m = *mp = NULL; 444 goto bad; 445 } 446 447 #if NPF > 0 448 if (pf_ouraddr(m) == 1) { 449 nxt = ip6_ours(mp, offp, nxt, af); 450 goto out; 451 } 452 #endif 453 454 /* 455 * Multicast check 456 */ 457 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 458 /* 459 * Make sure M_MCAST is set. It should theoretically 460 * already be there, but let's play safe because upper 461 * layers check for this flag. 462 */ 463 m->m_flags |= M_MCAST; 464 465 /* 466 * See if we belong to the destination multicast group on the 467 * arrival interface. 468 */ 469 if (in6_hasmulti(&ip6->ip6_dst, ifp)) 470 ours = 1; 471 472 #ifdef MROUTING 473 if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain]) { 474 int error; 475 476 nxt = ip6_hbhchcheck(&m, offp, &ours); 477 if (nxt == IPPROTO_DONE) 478 goto out; 479 480 ip6 = mtod(m, struct ip6_hdr *); 481 482 /* 483 * If we are acting as a multicast router, all 484 * incoming multicast packets are passed to the 485 * kernel-level multicast forwarding function. 486 * The packet is returned (relatively) intact; if 487 * ip6_mforward() returns a non-zero value, the packet 488 * must be discarded, else it may be accepted below. 489 */ 490 KERNEL_LOCK(); 491 error = ip6_mforward(ip6, ifp, m); 492 KERNEL_UNLOCK(); 493 if (error) { 494 ip6stat_inc(ip6s_cantforward); 495 goto bad; 496 } 497 498 if (ours) { 499 if (af == AF_UNSPEC) 500 nxt = ip6_ours(mp, offp, nxt, af); 501 goto out; 502 } 503 goto bad; 504 } 505 #endif 506 if (!ours) { 507 ip6stat_inc(ip6s_notmember); 508 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 509 ip6stat_inc(ip6s_cantforward); 510 goto bad; 511 } 512 nxt = ip6_ours(mp, offp, nxt, af); 513 goto out; 514 } 515 516 517 /* 518 * Unicast check 519 */ 520 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 521 sin6.sin6_len = sizeof(struct sockaddr_in6); 522 sin6.sin6_family = AF_INET6; 523 sin6.sin6_addr = ip6->ip6_dst; 524 rt = rtalloc_mpath(sin6tosa(&sin6), &ip6->ip6_src.s6_addr32[0], 525 m->m_pkthdr.ph_rtableid); 526 527 /* 528 * Accept the packet if the route to the destination is marked 529 * as local. 530 */ 531 if (rtisvalid(rt) && ISSET(rt->rt_flags, RTF_LOCAL)) { 532 struct in6_ifaddr *ia6 = ifatoia6(rt->rt_ifa); 533 534 if (ip6_forwarding == 0 && rt->rt_ifidx != ifp->if_index && 535 !((ifp->if_flags & IFF_LOOPBACK) || 536 (ifp->if_type == IFT_ENC) || 537 (m->m_pkthdr.pf.flags & PF_TAG_TRANSLATE_LOCALHOST))) { 538 /* received on wrong interface */ 539 #if NCARP > 0 540 struct ifnet *out_if; 541 542 /* 543 * Virtual IPs on carp interfaces need to be checked 544 * also against the parent interface and other carp 545 * interfaces sharing the same parent. 546 */ 547 out_if = if_get(rt->rt_ifidx); 548 if (!(out_if && carp_strict_addr_chk(out_if, ifp))) { 549 ip6stat_inc(ip6s_wrongif); 550 if_put(out_if); 551 goto bad; 552 } 553 if_put(out_if); 554 #else 555 ip6stat_inc(ip6s_wrongif); 556 goto bad; 557 #endif 558 } 559 /* 560 * packets to a tentative, duplicated, or somehow invalid 561 * address must not be accepted. 562 */ 563 if ((ia6->ia6_flags & (IN6_IFF_TENTATIVE|IN6_IFF_DUPLICATED))) { 564 char src[INET6_ADDRSTRLEN], dst[INET6_ADDRSTRLEN]; 565 566 inet_ntop(AF_INET6, &ip6->ip6_src, src, sizeof(src)); 567 inet_ntop(AF_INET6, &ip6->ip6_dst, dst, sizeof(dst)); 568 /* address is not ready, so discard the packet. */ 569 nd6log((LOG_INFO, 570 "%s: packet to an unready address %s->%s\n", 571 __func__, src, dst)); 572 573 goto bad; 574 } else { 575 nxt = ip6_ours(mp, offp, nxt, af); 576 goto out; 577 } 578 } 579 580 #if NCARP > 0 581 if (ip6->ip6_nxt == IPPROTO_ICMPV6 && 582 carp_lsdrop(ifp, m, AF_INET6, ip6->ip6_src.s6_addr32, 583 ip6->ip6_dst.s6_addr32, 1)) 584 goto bad; 585 #endif 586 /* 587 * Now there is no reason to process the packet if it's not our own 588 * and we're not a router. 589 */ 590 if (!ip6_forwarding) { 591 ip6stat_inc(ip6s_cantforward); 592 goto bad; 593 } 594 595 nxt = ip6_hbhchcheck(&m, offp, &ours); 596 if (nxt == IPPROTO_DONE) 597 goto out; 598 599 if (ours) { 600 if (af == AF_UNSPEC) 601 nxt = ip6_ours(mp, offp, nxt, af); 602 goto out; 603 } 604 605 #ifdef IPSEC 606 if (ipsec_in_use) { 607 int rv; 608 609 rv = ipsec_forward_check(m, *offp, AF_INET6); 610 if (rv != 0) { 611 ip6stat_inc(ip6s_cantforward); 612 goto bad; 613 } 614 /* 615 * Fall through, forward packet. Outbound IPsec policy 616 * checking will occur in ip6_forward(). 617 */ 618 } 619 #endif /* IPSEC */ 620 621 ip6_forward(m, rt, srcrt); 622 *mp = NULL; 623 return IPPROTO_DONE; 624 bad: 625 nxt = IPPROTO_DONE; 626 m_freemp(mp); 627 out: 628 rtfree(rt); 629 return nxt; 630 } 631 632 /* On error free mbuf and return IPPROTO_DONE. */ 633 int 634 ip6_hbhchcheck(struct mbuf **mp, int *offp, int *oursp) 635 { 636 struct ip6_hdr *ip6; 637 u_int32_t plen, rtalert = ~0; 638 int nxt; 639 640 ip6 = mtod(*mp, struct ip6_hdr *); 641 642 /* 643 * Process Hop-by-Hop options header if it's contained. 644 * m may be modified in ip6_hopopts_input(). 645 * If a JumboPayload option is included, plen will also be modified. 646 */ 647 plen = (u_int32_t)ntohs(ip6->ip6_plen); 648 *offp = sizeof(struct ip6_hdr); 649 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 650 struct ip6_hbh *hbh; 651 652 if (ip6_hopopts_input(mp, offp, &plen, &rtalert)) 653 goto bad; /* m have already been freed */ 654 655 /* adjust pointer */ 656 ip6 = mtod(*mp, struct ip6_hdr *); 657 658 /* 659 * if the payload length field is 0 and the next header field 660 * indicates Hop-by-Hop Options header, then a Jumbo Payload 661 * option MUST be included. 662 */ 663 if (ip6->ip6_plen == 0 && plen == 0) { 664 /* 665 * Note that if a valid jumbo payload option is 666 * contained, ip6_hopopts_input() must set a valid 667 * (non-zero) payload length to the variable plen. 668 */ 669 ip6stat_inc(ip6s_badoptions); 670 icmp6_error(*mp, ICMP6_PARAM_PROB, 671 ICMP6_PARAMPROB_HEADER, 672 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 673 goto bad; 674 } 675 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, *mp, 676 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 677 if (hbh == NULL) { 678 ip6stat_inc(ip6s_tooshort); 679 goto bad; 680 } 681 nxt = hbh->ip6h_nxt; 682 683 /* 684 * accept the packet if a router alert option is included 685 * and we act as an IPv6 router. 686 */ 687 if (rtalert != ~0 && ip6_forwarding && oursp != NULL) 688 *oursp = 1; 689 } else 690 nxt = ip6->ip6_nxt; 691 692 /* 693 * Check that the amount of data in the buffers 694 * is as at least much as the IPv6 header would have us expect. 695 * Trim mbufs if longer than we expect. 696 * Drop packet if shorter than we expect. 697 */ 698 if ((*mp)->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 699 ip6stat_inc(ip6s_tooshort); 700 m_freemp(mp); 701 goto bad; 702 } 703 if ((*mp)->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 704 if ((*mp)->m_len == (*mp)->m_pkthdr.len) { 705 (*mp)->m_len = sizeof(struct ip6_hdr) + plen; 706 (*mp)->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 707 } else { 708 m_adj((*mp), sizeof(struct ip6_hdr) + plen - 709 (*mp)->m_pkthdr.len); 710 } 711 } 712 713 return nxt; 714 bad: 715 return IPPROTO_DONE; 716 } 717 718 /* scan packet for RH0 routing header. Mostly stolen from pf.c:pf_test() */ 719 int 720 ip6_check_rh0hdr(struct mbuf *m, int *offp) 721 { 722 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 723 struct ip6_rthdr rthdr; 724 struct ip6_ext opt6; 725 u_int8_t proto = ip6->ip6_nxt; 726 int done = 0, lim, off, rh_cnt = 0; 727 728 off = ((caddr_t)ip6 - m->m_data) + sizeof(struct ip6_hdr); 729 lim = min(m->m_pkthdr.len, ntohs(ip6->ip6_plen) + sizeof(*ip6)); 730 do { 731 switch (proto) { 732 case IPPROTO_ROUTING: 733 if (rh_cnt++) { 734 /* more than one rh header present */ 735 *offp = off; 736 return (1); 737 } 738 739 if (off + sizeof(rthdr) > lim) { 740 /* packet to short to make sense */ 741 *offp = off; 742 return (1); 743 } 744 745 m_copydata(m, off, sizeof(rthdr), &rthdr); 746 747 if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) { 748 *offp = off + 749 offsetof(struct ip6_rthdr, ip6r_type); 750 return (1); 751 } 752 753 off += (rthdr.ip6r_len + 1) * 8; 754 proto = rthdr.ip6r_nxt; 755 break; 756 case IPPROTO_AH: 757 case IPPROTO_HOPOPTS: 758 case IPPROTO_DSTOPTS: 759 /* get next header and header length */ 760 if (off + sizeof(opt6) > lim) { 761 /* 762 * Packet to short to make sense, we could 763 * reject the packet but as a router we 764 * should not do that so forward it. 765 */ 766 return (0); 767 } 768 769 m_copydata(m, off, sizeof(opt6), &opt6); 770 771 if (proto == IPPROTO_AH) 772 off += (opt6.ip6e_len + 2) * 4; 773 else 774 off += (opt6.ip6e_len + 1) * 8; 775 proto = opt6.ip6e_nxt; 776 break; 777 case IPPROTO_FRAGMENT: 778 default: 779 /* end of header stack */ 780 done = 1; 781 break; 782 } 783 } while (!done); 784 785 return (0); 786 } 787 788 /* 789 * Hop-by-Hop options header processing. If a valid jumbo payload option is 790 * included, the real payload length will be stored in plenp. 791 * On error free mbuf and return -1. 792 * 793 * rtalertp - XXX: should be stored in a more smart way 794 */ 795 int 796 ip6_hopopts_input(struct mbuf **mp, int *offp, u_int32_t *plenp, 797 u_int32_t *rtalertp) 798 { 799 int off = *offp, hbhlen; 800 struct ip6_hbh *hbh; 801 802 /* validation of the length of the header */ 803 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, *mp, 804 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 805 if (hbh == NULL) { 806 ip6stat_inc(ip6s_tooshort); 807 return -1; 808 } 809 hbhlen = (hbh->ip6h_len + 1) << 3; 810 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, *mp, sizeof(struct ip6_hdr), 811 hbhlen); 812 if (hbh == NULL) { 813 ip6stat_inc(ip6s_tooshort); 814 return -1; 815 } 816 off += hbhlen; 817 hbhlen -= sizeof(struct ip6_hbh); 818 819 if (ip6_process_hopopts(mp, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 820 hbhlen, rtalertp, plenp) < 0) 821 return (-1); 822 823 *offp = off; 824 return (0); 825 } 826 827 /* 828 * Search header for all Hop-by-hop options and process each option. 829 * This function is separate from ip6_hopopts_input() in order to 830 * handle a case where the sending node itself process its hop-by-hop 831 * options header. In such a case, the function is called from ip6_output(). 832 * On error free mbuf and return -1. 833 * 834 * The function assumes that hbh header is located right after the IPv6 header 835 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 836 * opthead + hbhlen is located in continuous memory region. 837 */ 838 int 839 ip6_process_hopopts(struct mbuf **mp, u_int8_t *opthead, int hbhlen, 840 u_int32_t *rtalertp, u_int32_t *plenp) 841 { 842 struct ip6_hdr *ip6; 843 int optlen = 0; 844 u_int8_t *opt = opthead; 845 u_int16_t rtalert_val; 846 u_int32_t jumboplen; 847 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 848 849 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 850 switch (*opt) { 851 case IP6OPT_PAD1: 852 optlen = 1; 853 break; 854 case IP6OPT_PADN: 855 if (hbhlen < IP6OPT_MINLEN) { 856 ip6stat_inc(ip6s_toosmall); 857 goto bad; 858 } 859 optlen = *(opt + 1) + 2; 860 break; 861 case IP6OPT_ROUTER_ALERT: 862 /* XXX may need check for alignment */ 863 if (hbhlen < IP6OPT_RTALERT_LEN) { 864 ip6stat_inc(ip6s_toosmall); 865 goto bad; 866 } 867 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 868 /* XXX stat */ 869 icmp6_error(*mp, ICMP6_PARAM_PROB, 870 ICMP6_PARAMPROB_HEADER, 871 erroff + opt + 1 - opthead); 872 return (-1); 873 } 874 optlen = IP6OPT_RTALERT_LEN; 875 memcpy((caddr_t)&rtalert_val, (caddr_t)(opt + 2), 2); 876 *rtalertp = ntohs(rtalert_val); 877 break; 878 case IP6OPT_JUMBO: 879 /* XXX may need check for alignment */ 880 if (hbhlen < IP6OPT_JUMBO_LEN) { 881 ip6stat_inc(ip6s_toosmall); 882 goto bad; 883 } 884 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 885 /* XXX stat */ 886 icmp6_error(*mp, ICMP6_PARAM_PROB, 887 ICMP6_PARAMPROB_HEADER, 888 erroff + opt + 1 - opthead); 889 return (-1); 890 } 891 optlen = IP6OPT_JUMBO_LEN; 892 893 /* 894 * IPv6 packets that have non 0 payload length 895 * must not contain a jumbo payload option. 896 */ 897 ip6 = mtod(*mp, struct ip6_hdr *); 898 if (ip6->ip6_plen) { 899 ip6stat_inc(ip6s_badoptions); 900 icmp6_error(*mp, ICMP6_PARAM_PROB, 901 ICMP6_PARAMPROB_HEADER, 902 erroff + opt - opthead); 903 return (-1); 904 } 905 906 /* 907 * We may see jumbolen in unaligned location, so 908 * we'd need to perform memcpy(). 909 */ 910 memcpy(&jumboplen, opt + 2, sizeof(jumboplen)); 911 jumboplen = (u_int32_t)htonl(jumboplen); 912 913 #if 1 914 /* 915 * if there are multiple jumbo payload options, 916 * *plenp will be non-zero and the packet will be 917 * rejected. 918 * the behavior may need some debate in ipngwg - 919 * multiple options does not make sense, however, 920 * there's no explicit mention in specification. 921 */ 922 if (*plenp != 0) { 923 ip6stat_inc(ip6s_badoptions); 924 icmp6_error(*mp, ICMP6_PARAM_PROB, 925 ICMP6_PARAMPROB_HEADER, 926 erroff + opt + 2 - opthead); 927 return (-1); 928 } 929 #endif 930 931 /* 932 * jumbo payload length must be larger than 65535. 933 */ 934 if (jumboplen <= IPV6_MAXPACKET) { 935 ip6stat_inc(ip6s_badoptions); 936 icmp6_error(*mp, ICMP6_PARAM_PROB, 937 ICMP6_PARAMPROB_HEADER, 938 erroff + opt + 2 - opthead); 939 return (-1); 940 } 941 *plenp = jumboplen; 942 943 break; 944 default: /* unknown option */ 945 if (hbhlen < IP6OPT_MINLEN) { 946 ip6stat_inc(ip6s_toosmall); 947 goto bad; 948 } 949 optlen = ip6_unknown_opt(mp, opt, 950 erroff + opt - opthead); 951 if (optlen == -1) 952 return (-1); 953 optlen += 2; 954 break; 955 } 956 } 957 958 return (0); 959 960 bad: 961 m_freemp(mp); 962 return (-1); 963 } 964 965 /* 966 * Unknown option processing. 967 * The third argument `off' is the offset from the IPv6 header to the option, 968 * which allows returning an ICMPv6 error even if the IPv6 header and the 969 * option header are not continuous. 970 * On error free mbuf and return -1. 971 */ 972 int 973 ip6_unknown_opt(struct mbuf **mp, u_int8_t *optp, int off) 974 { 975 struct ip6_hdr *ip6; 976 977 switch (IP6OPT_TYPE(*optp)) { 978 case IP6OPT_TYPE_SKIP: /* ignore the option */ 979 return ((int)*(optp + 1)); 980 case IP6OPT_TYPE_DISCARD: /* silently discard */ 981 m_freemp(mp); 982 return (-1); 983 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 984 ip6stat_inc(ip6s_badoptions); 985 icmp6_error(*mp, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 986 return (-1); 987 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 988 ip6stat_inc(ip6s_badoptions); 989 ip6 = mtod(*mp, struct ip6_hdr *); 990 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 991 ((*mp)->m_flags & (M_BCAST|M_MCAST))) 992 m_freemp(mp); 993 else 994 icmp6_error(*mp, ICMP6_PARAM_PROB, 995 ICMP6_PARAMPROB_OPTION, off); 996 return (-1); 997 } 998 999 m_freemp(mp); /* XXX: NOTREACHED */ 1000 return (-1); 1001 } 1002 1003 /* 1004 * Create the "control" list for this pcb. 1005 * 1006 * The routine will be called from upper layer handlers like udp_input(). 1007 * Thus the routine assumes that the caller (udp_input) have already 1008 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1009 * very first mbuf on the mbuf chain. 1010 * We may want to add some infinite loop prevention or sanity checks for safety. 1011 * (This applies only when you are using KAME mbuf chain restriction, i.e. 1012 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 1013 */ 1014 void 1015 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 1016 { 1017 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1018 1019 if (in6p->inp_socket->so_options & SO_TIMESTAMP) { 1020 struct timeval tv; 1021 1022 m_microtime(m, &tv); 1023 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1024 SCM_TIMESTAMP, SOL_SOCKET); 1025 if (*mp) 1026 mp = &(*mp)->m_next; 1027 } 1028 1029 /* RFC 2292 sec. 5 */ 1030 if ((in6p->inp_flags & IN6P_PKTINFO) != 0) { 1031 struct in6_pktinfo pi6; 1032 memcpy(&pi6.ipi6_addr, &ip6->ip6_dst, sizeof(struct in6_addr)); 1033 if (IN6_IS_SCOPE_EMBED(&pi6.ipi6_addr)) 1034 pi6.ipi6_addr.s6_addr16[1] = 0; 1035 pi6.ipi6_ifindex = m ? m->m_pkthdr.ph_ifidx : 0; 1036 *mp = sbcreatecontrol((caddr_t) &pi6, 1037 sizeof(struct in6_pktinfo), 1038 IPV6_PKTINFO, IPPROTO_IPV6); 1039 if (*mp) 1040 mp = &(*mp)->m_next; 1041 } 1042 1043 if ((in6p->inp_flags & IN6P_HOPLIMIT) != 0) { 1044 int hlim = ip6->ip6_hlim & 0xff; 1045 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 1046 IPV6_HOPLIMIT, IPPROTO_IPV6); 1047 if (*mp) 1048 mp = &(*mp)->m_next; 1049 } 1050 1051 if ((in6p->inp_flags & IN6P_TCLASS) != 0) { 1052 u_int32_t flowinfo; 1053 int tclass; 1054 1055 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1056 flowinfo >>= 20; 1057 1058 tclass = flowinfo & 0xff; 1059 *mp = sbcreatecontrol((caddr_t)&tclass, sizeof(tclass), 1060 IPV6_TCLASS, IPPROTO_IPV6); 1061 if (*mp) 1062 mp = &(*mp)->m_next; 1063 } 1064 1065 /* 1066 * IPV6_HOPOPTS socket option. Recall that we required super-user 1067 * privilege for the option (see ip6_ctloutput), but it might be too 1068 * strict, since there might be some hop-by-hop options which can be 1069 * returned to normal user. 1070 * See also RFC 2292 section 6 (or RFC 3542 section 8). 1071 */ 1072 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 1073 /* 1074 * Check if a hop-by-hop options header is contained in the 1075 * received packet, and if so, store the options as ancillary 1076 * data. Note that a hop-by-hop options header must be 1077 * just after the IPv6 header, which is assured through the 1078 * IPv6 input processing. 1079 */ 1080 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1081 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1082 struct ip6_hbh *hbh; 1083 int hbhlen = 0; 1084 struct mbuf *ext; 1085 1086 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1087 ip6->ip6_nxt); 1088 if (ext == NULL) { 1089 ip6stat_inc(ip6s_tooshort); 1090 return; 1091 } 1092 hbh = mtod(ext, struct ip6_hbh *); 1093 hbhlen = (hbh->ip6h_len + 1) << 3; 1094 if (hbhlen != ext->m_len) { 1095 m_freem(ext); 1096 ip6stat_inc(ip6s_tooshort); 1097 return; 1098 } 1099 1100 /* 1101 * XXX: We copy the whole header even if a 1102 * jumbo payload option is included, the option which 1103 * is to be removed before returning according to 1104 * RFC2292. 1105 * Note: this constraint is removed in RFC3542. 1106 */ 1107 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1108 IPV6_HOPOPTS, 1109 IPPROTO_IPV6); 1110 if (*mp) 1111 mp = &(*mp)->m_next; 1112 m_freem(ext); 1113 } 1114 } 1115 1116 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1117 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1118 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1119 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1120 1121 /* 1122 * Search for destination options headers or routing 1123 * header(s) through the header chain, and stores each 1124 * header as ancillary data. 1125 * Note that the order of the headers remains in 1126 * the chain of ancillary data. 1127 */ 1128 while (1) { /* is explicit loop prevention necessary? */ 1129 struct ip6_ext *ip6e = NULL; 1130 int elen; 1131 struct mbuf *ext = NULL; 1132 1133 /* 1134 * if it is not an extension header, don't try to 1135 * pull it from the chain. 1136 */ 1137 switch (nxt) { 1138 case IPPROTO_DSTOPTS: 1139 case IPPROTO_ROUTING: 1140 case IPPROTO_HOPOPTS: 1141 case IPPROTO_AH: /* is it possible? */ 1142 break; 1143 default: 1144 goto loopend; 1145 } 1146 1147 ext = ip6_pullexthdr(m, off, nxt); 1148 if (ext == NULL) { 1149 ip6stat_inc(ip6s_tooshort); 1150 return; 1151 } 1152 ip6e = mtod(ext, struct ip6_ext *); 1153 if (nxt == IPPROTO_AH) 1154 elen = (ip6e->ip6e_len + 2) << 2; 1155 else 1156 elen = (ip6e->ip6e_len + 1) << 3; 1157 if (elen != ext->m_len) { 1158 m_freem(ext); 1159 ip6stat_inc(ip6s_tooshort); 1160 return; 1161 } 1162 1163 switch (nxt) { 1164 case IPPROTO_DSTOPTS: 1165 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1166 break; 1167 1168 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1169 IPV6_DSTOPTS, 1170 IPPROTO_IPV6); 1171 if (*mp) 1172 mp = &(*mp)->m_next; 1173 break; 1174 1175 case IPPROTO_ROUTING: 1176 if (!(in6p->inp_flags & IN6P_RTHDR)) 1177 break; 1178 1179 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1180 IPV6_RTHDR, 1181 IPPROTO_IPV6); 1182 if (*mp) 1183 mp = &(*mp)->m_next; 1184 break; 1185 1186 case IPPROTO_HOPOPTS: 1187 case IPPROTO_AH: /* is it possible? */ 1188 break; 1189 1190 default: 1191 /* 1192 * other cases have been filtered in the above. 1193 * none will visit this case. here we supply 1194 * the code just in case (nxt overwritten or 1195 * other cases). 1196 */ 1197 m_freem(ext); 1198 goto loopend; 1199 1200 } 1201 1202 /* proceed with the next header. */ 1203 off += elen; 1204 nxt = ip6e->ip6e_nxt; 1205 ip6e = NULL; 1206 m_freem(ext); 1207 ext = NULL; 1208 } 1209 loopend: 1210 ; 1211 } 1212 } 1213 1214 /* 1215 * pull single extension header from mbuf chain. returns single mbuf that 1216 * contains the result, or NULL on error. 1217 */ 1218 struct mbuf * 1219 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1220 { 1221 struct ip6_ext ip6e; 1222 size_t elen; 1223 struct mbuf *n; 1224 1225 #ifdef DIAGNOSTIC 1226 switch (nxt) { 1227 case IPPROTO_DSTOPTS: 1228 case IPPROTO_ROUTING: 1229 case IPPROTO_HOPOPTS: 1230 case IPPROTO_AH: /* is it possible? */ 1231 break; 1232 default: 1233 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1234 } 1235 #endif 1236 1237 if (off + sizeof(ip6e) > m->m_pkthdr.len) 1238 return NULL; 1239 1240 m_copydata(m, off, sizeof(ip6e), &ip6e); 1241 if (nxt == IPPROTO_AH) 1242 elen = (ip6e.ip6e_len + 2) << 2; 1243 else 1244 elen = (ip6e.ip6e_len + 1) << 3; 1245 1246 if (off + elen > m->m_pkthdr.len) 1247 return NULL; 1248 1249 MGET(n, M_DONTWAIT, MT_DATA); 1250 if (n && elen >= MLEN) { 1251 MCLGET(n, M_DONTWAIT); 1252 if ((n->m_flags & M_EXT) == 0) { 1253 m_free(n); 1254 n = NULL; 1255 } 1256 } 1257 if (n == NULL) { 1258 ip6stat_inc(ip6s_idropped); 1259 return NULL; 1260 } 1261 1262 n->m_len = 0; 1263 if (elen >= m_trailingspace(n)) { 1264 m_free(n); 1265 return NULL; 1266 } 1267 1268 m_copydata(m, off, elen, mtod(n, caddr_t)); 1269 n->m_len = elen; 1270 return n; 1271 } 1272 1273 /* 1274 * Get offset to the previous header followed by the header 1275 * currently processed. 1276 */ 1277 int 1278 ip6_get_prevhdr(struct mbuf *m, int off) 1279 { 1280 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1281 1282 if (off == sizeof(struct ip6_hdr)) { 1283 return offsetof(struct ip6_hdr, ip6_nxt); 1284 } else if (off < sizeof(struct ip6_hdr)) { 1285 panic("%s: off < sizeof(struct ip6_hdr)", __func__); 1286 } else { 1287 int len, nlen, nxt; 1288 struct ip6_ext ip6e; 1289 1290 nxt = ip6->ip6_nxt; 1291 len = sizeof(struct ip6_hdr); 1292 nlen = 0; 1293 while (len < off) { 1294 m_copydata(m, len, sizeof(ip6e), &ip6e); 1295 1296 switch (nxt) { 1297 case IPPROTO_FRAGMENT: 1298 nlen = sizeof(struct ip6_frag); 1299 break; 1300 case IPPROTO_AH: 1301 nlen = (ip6e.ip6e_len + 2) << 2; 1302 break; 1303 default: 1304 nlen = (ip6e.ip6e_len + 1) << 3; 1305 break; 1306 } 1307 len += nlen; 1308 nxt = ip6e.ip6e_nxt; 1309 } 1310 1311 return (len - nlen); 1312 } 1313 } 1314 1315 /* 1316 * get next header offset. m will be retained. 1317 */ 1318 int 1319 ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp) 1320 { 1321 struct ip6_hdr ip6; 1322 struct ip6_ext ip6e; 1323 struct ip6_frag fh; 1324 1325 /* just in case */ 1326 if (m == NULL) 1327 panic("%s: m == NULL", __func__); 1328 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1329 return -1; 1330 1331 switch (proto) { 1332 case IPPROTO_IPV6: 1333 if (m->m_pkthdr.len < off + sizeof(ip6)) 1334 return -1; 1335 m_copydata(m, off, sizeof(ip6), &ip6); 1336 if (nxtp) 1337 *nxtp = ip6.ip6_nxt; 1338 off += sizeof(ip6); 1339 return off; 1340 1341 case IPPROTO_FRAGMENT: 1342 /* 1343 * terminate parsing if it is not the first fragment, 1344 * it does not make sense to parse through it. 1345 */ 1346 if (m->m_pkthdr.len < off + sizeof(fh)) 1347 return -1; 1348 m_copydata(m, off, sizeof(fh), &fh); 1349 if ((fh.ip6f_offlg & IP6F_OFF_MASK) != 0) 1350 return -1; 1351 if (nxtp) 1352 *nxtp = fh.ip6f_nxt; 1353 off += sizeof(struct ip6_frag); 1354 return off; 1355 1356 case IPPROTO_AH: 1357 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1358 return -1; 1359 m_copydata(m, off, sizeof(ip6e), &ip6e); 1360 if (nxtp) 1361 *nxtp = ip6e.ip6e_nxt; 1362 off += (ip6e.ip6e_len + 2) << 2; 1363 if (m->m_pkthdr.len < off) 1364 return -1; 1365 return off; 1366 1367 case IPPROTO_HOPOPTS: 1368 case IPPROTO_ROUTING: 1369 case IPPROTO_DSTOPTS: 1370 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1371 return -1; 1372 m_copydata(m, off, sizeof(ip6e), &ip6e); 1373 if (nxtp) 1374 *nxtp = ip6e.ip6e_nxt; 1375 off += (ip6e.ip6e_len + 1) << 3; 1376 if (m->m_pkthdr.len < off) 1377 return -1; 1378 return off; 1379 1380 case IPPROTO_NONE: 1381 case IPPROTO_ESP: 1382 case IPPROTO_IPCOMP: 1383 /* give up */ 1384 return -1; 1385 1386 default: 1387 return -1; 1388 } 1389 1390 return -1; 1391 } 1392 1393 /* 1394 * get offset for the last header in the chain. m will be kept untainted. 1395 */ 1396 int 1397 ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp) 1398 { 1399 int newoff; 1400 int nxt; 1401 1402 if (!nxtp) { 1403 nxt = -1; 1404 nxtp = &nxt; 1405 } 1406 while (1) { 1407 newoff = ip6_nexthdr(m, off, proto, nxtp); 1408 if (newoff < 0) 1409 return off; 1410 else if (newoff < off) 1411 return -1; /* invalid */ 1412 else if (newoff == off) 1413 return newoff; 1414 1415 off = newoff; 1416 proto = *nxtp; 1417 } 1418 } 1419 1420 /* 1421 * System control for IP6 1422 */ 1423 1424 const u_char inet6ctlerrmap[PRC_NCMDS] = { 1425 0, 0, 0, 0, 1426 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1427 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1428 EMSGSIZE, EHOSTUNREACH, 0, 0, 1429 0, 0, 0, 0, 1430 ENOPROTOOPT 1431 }; 1432 1433 #ifdef MROUTING 1434 extern int ip6_mrtproto; 1435 #endif 1436 1437 const struct sysctl_bounded_args ipv6ctl_vars[] = { 1438 { IPV6CTL_DAD_PENDING, &ip6_dad_pending, SYSCTL_INT_READONLY }, 1439 #ifdef MROUTING 1440 { IPV6CTL_MRTPROTO, &ip6_mrtproto, SYSCTL_INT_READONLY }, 1441 #endif 1442 { IPV6CTL_FORWARDING, &ip6_forwarding, 0, 1 }, 1443 { IPV6CTL_SENDREDIRECTS, &ip6_sendredirects, 0, 1 }, 1444 { IPV6CTL_DEFHLIM, &ip6_defhlim, 0, 255 }, 1445 { IPV6CTL_MAXFRAGPACKETS, &ip6_maxfragpackets, 0, 1000 }, 1446 { IPV6CTL_LOG_INTERVAL, &ip6_log_interval, 0, INT_MAX }, 1447 { IPV6CTL_HDRNESTLIMIT, &ip6_hdrnestlimit, 0, 100 }, 1448 { IPV6CTL_DAD_COUNT, &ip6_dad_count, 0, 10 }, 1449 { IPV6CTL_AUTO_FLOWLABEL, &ip6_auto_flowlabel, 0, 1 }, 1450 { IPV6CTL_DEFMCASTHLIM, &ip6_defmcasthlim, 0, 255 }, 1451 { IPV6CTL_USE_DEPRECATED, &ip6_use_deprecated, 0, 1 }, 1452 { IPV6CTL_MAXFRAGS, &ip6_maxfrags, 0, 1000 }, 1453 { IPV6CTL_MFORWARDING, &ip6_mforwarding, 0, 1 }, 1454 { IPV6CTL_MULTIPATH, &ip6_multipath, 0, 1 }, 1455 { IPV6CTL_MCAST_PMTU, &ip6_mcast_pmtu, 0, 1 }, 1456 { IPV6CTL_NEIGHBORGCTHRESH, &ip6_neighborgcthresh, -1, 5 * 2048 }, 1457 { IPV6CTL_MAXDYNROUTES, &ip6_maxdynroutes, -1, 5 * 4096 }, 1458 }; 1459 1460 int 1461 ip6_sysctl_ip6stat(void *oldp, size_t *oldlenp, void *newp) 1462 { 1463 struct ip6stat *ip6stat; 1464 int ret; 1465 1466 CTASSERT(sizeof(*ip6stat) == (ip6s_ncounters * sizeof(uint64_t))); 1467 1468 ip6stat = malloc(sizeof(*ip6stat), M_TEMP, M_WAITOK); 1469 counters_read(ip6counters, (uint64_t *)ip6stat, ip6s_ncounters); 1470 ret = sysctl_rdstruct(oldp, oldlenp, newp, 1471 ip6stat, sizeof(*ip6stat)); 1472 free(ip6stat, M_TEMP, sizeof(*ip6stat)); 1473 1474 return (ret); 1475 } 1476 1477 int 1478 ip6_sysctl_soiikey(void *oldp, size_t *oldlenp, void *newp, size_t newlen) 1479 { 1480 uint8_t oldkey[IP6_SOIIKEY_LEN]; 1481 int error; 1482 1483 error = suser(curproc); 1484 if (error != 0) 1485 return (error); 1486 1487 memcpy(oldkey, ip6_soiikey, sizeof(oldkey)); 1488 1489 error = sysctl_struct(oldp, oldlenp, newp, newlen, ip6_soiikey, 1490 sizeof(ip6_soiikey)); 1491 1492 return (error); 1493 } 1494 1495 int 1496 ip6_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, 1497 void *newp, size_t newlen) 1498 { 1499 #ifdef MROUTING 1500 extern struct mrt6stat mrt6stat; 1501 #endif 1502 int error; 1503 1504 /* Almost all sysctl names at this level are terminal. */ 1505 if (namelen != 1 && name[0] != IPV6CTL_IFQUEUE) 1506 return (ENOTDIR); 1507 1508 switch (name[0]) { 1509 case IPV6CTL_STATS: 1510 return (ip6_sysctl_ip6stat(oldp, oldlenp, newp)); 1511 #ifdef MROUTING 1512 case IPV6CTL_MRTSTATS: 1513 if (newp != NULL) 1514 return (EPERM); 1515 NET_LOCK(); 1516 error = sysctl_struct(oldp, oldlenp, newp, newlen, 1517 &mrt6stat, sizeof(mrt6stat)); 1518 NET_UNLOCK(); 1519 return (error); 1520 case IPV6CTL_MRTMIF: 1521 if (newp) 1522 return (EPERM); 1523 NET_LOCK(); 1524 error = mrt6_sysctl_mif(oldp, oldlenp); 1525 NET_UNLOCK(); 1526 return (error); 1527 case IPV6CTL_MRTMFC: 1528 if (newp) 1529 return (EPERM); 1530 NET_LOCK(); 1531 error = mrt6_sysctl_mfc(oldp, oldlenp); 1532 NET_UNLOCK(); 1533 return (error); 1534 #else 1535 case IPV6CTL_MRTSTATS: 1536 case IPV6CTL_MRTPROTO: 1537 case IPV6CTL_MRTMIF: 1538 case IPV6CTL_MRTMFC: 1539 return (EOPNOTSUPP); 1540 #endif 1541 case IPV6CTL_MTUDISCTIMEOUT: 1542 NET_LOCK(); 1543 error = sysctl_int_bounded(oldp, oldlenp, newp, newlen, 1544 &ip6_mtudisc_timeout, 0, INT_MAX); 1545 rt_timer_queue_change(&icmp6_mtudisc_timeout_q, 1546 ip6_mtudisc_timeout); 1547 NET_UNLOCK(); 1548 return (error); 1549 case IPV6CTL_IFQUEUE: 1550 return (sysctl_niq(name + 1, namelen - 1, 1551 oldp, oldlenp, newp, newlen, &ip6intrq)); 1552 case IPV6CTL_SOIIKEY: 1553 return (ip6_sysctl_soiikey(oldp, oldlenp, newp, newlen)); 1554 default: 1555 NET_LOCK(); 1556 error = sysctl_bounded_arr(ipv6ctl_vars, nitems(ipv6ctl_vars), 1557 name, namelen, oldp, oldlenp, newp, newlen); 1558 NET_UNLOCK(); 1559 return (error); 1560 } 1561 /* NOTREACHED */ 1562 } 1563 1564 void 1565 ip6_send_dispatch(void *xmq) 1566 { 1567 struct mbuf_queue *mq = xmq; 1568 struct mbuf *m; 1569 struct mbuf_list ml; 1570 1571 mq_delist(mq, &ml); 1572 if (ml_empty(&ml)) 1573 return; 1574 1575 NET_LOCK(); 1576 while ((m = ml_dequeue(&ml)) != NULL) { 1577 ip6_output(m, NULL, NULL, 0, NULL, NULL); 1578 } 1579 NET_UNLOCK(); 1580 } 1581 1582 void 1583 ip6_send(struct mbuf *m) 1584 { 1585 mq_enqueue(&ip6send_mq, m); 1586 task_add(net_tq(0), &ip6send_task); 1587 }
Cache object: e00ea09229fd5cfc8bfa40d84904c562
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