ip6_input.c revision 256281
1/*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $ 30 */ 31 32/*- 33 * Copyright (c) 1982, 1986, 1988, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 4. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 * 60 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 61 */ 62 63#include <sys/cdefs.h> 64__FBSDID("$FreeBSD: stable/10/sys/netinet6/ip6_input.c 255523 2013-09-13 18:45:10Z trociny $"); 65 66#include "opt_inet.h" 67#include "opt_inet6.h" 68#include "opt_ipfw.h" 69#include "opt_ipsec.h" 70#include "opt_kdtrace.h" 71#include "opt_route.h" 72 73#include <sys/param.h> 74#include <sys/systm.h> 75#include <sys/malloc.h> 76#include <sys/mbuf.h> 77#include <sys/proc.h> 78#include <sys/domain.h> 79#include <sys/protosw.h> 80#include <sys/sdt.h> 81#include <sys/socket.h> 82#include <sys/socketvar.h> 83#include <sys/errno.h> 84#include <sys/time.h> 85#include <sys/kernel.h> 86#include <sys/syslog.h> 87 88#include <net/if.h> 89#include <net/if_types.h> 90#include <net/if_dl.h> 91#include <net/route.h> 92#include <net/netisr.h> 93#include <net/pfil.h> 94#include <net/vnet.h> 95 96#include <netinet/in.h> 97#include <netinet/in_kdtrace.h> 98#include <netinet/ip_var.h> 99#include <netinet/in_systm.h> 100#include <net/if_llatbl.h> 101#ifdef INET 102#include <netinet/ip.h> 103#include <netinet/ip_icmp.h> 104#endif /* INET */ 105#include <netinet/ip6.h> 106#include <netinet6/in6_var.h> 107#include <netinet6/ip6_var.h> 108#include <netinet/in_pcb.h> 109#include <netinet/icmp6.h> 110#include <netinet6/scope6_var.h> 111#include <netinet6/in6_ifattach.h> 112#include <netinet6/nd6.h> 113 114#ifdef IPSEC 115#include <netipsec/ipsec.h> 116#include <netinet6/ip6_ipsec.h> 117#include <netipsec/ipsec6.h> 118#endif /* IPSEC */ 119 120#include <netinet6/ip6protosw.h> 121 122#ifdef FLOWTABLE 123#include <net/flowtable.h> 124VNET_DECLARE(int, ip6_output_flowtable_size); 125#define V_ip6_output_flowtable_size VNET(ip6_output_flowtable_size) 126#endif 127 128extern struct domain inet6domain; 129 130u_char ip6_protox[IPPROTO_MAX]; 131VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead); 132VNET_DEFINE(struct in6_ifaddrlisthead *, in6_ifaddrhashtbl); 133VNET_DEFINE(u_long, in6_ifaddrhmask); 134 135static struct netisr_handler ip6_nh = { 136 .nh_name = "ip6", 137 .nh_handler = ip6_input, 138 .nh_proto = NETISR_IPV6, 139 .nh_policy = NETISR_POLICY_FLOW, 140}; 141 142VNET_DECLARE(struct callout, in6_tmpaddrtimer_ch); 143#define V_in6_tmpaddrtimer_ch VNET(in6_tmpaddrtimer_ch) 144 145VNET_DEFINE(struct pfil_head, inet6_pfil_hook); 146 147VNET_PCPUSTAT_DEFINE(struct ip6stat, ip6stat); 148VNET_PCPUSTAT_SYSINIT(ip6stat); 149#ifdef VIMAGE 150VNET_PCPUSTAT_SYSUNINIT(ip6stat); 151#endif /* VIMAGE */ 152 153struct rwlock in6_ifaddr_lock; 154RW_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock"); 155 156static void ip6_init2(void *); 157static struct ip6aux *ip6_setdstifaddr(struct mbuf *, struct in6_ifaddr *); 158static struct ip6aux *ip6_addaux(struct mbuf *); 159static struct ip6aux *ip6_findaux(struct mbuf *m); 160static void ip6_delaux (struct mbuf *); 161static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *); 162#ifdef PULLDOWN_TEST 163static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int); 164#endif 165 166/* 167 * IP6 initialization: fill in IP6 protocol switch table. 168 * All protocols not implemented in kernel go to raw IP6 protocol handler. 169 */ 170void 171ip6_init(void) 172{ 173 struct ip6protosw *pr; 174 int i; 175 176 TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal", 177 &V_ip6_auto_linklocal); 178 TUNABLE_INT_FETCH("net.inet6.ip6.accept_rtadv", &V_ip6_accept_rtadv); 179 TUNABLE_INT_FETCH("net.inet6.ip6.no_radr", &V_ip6_no_radr); 180 181 TAILQ_INIT(&V_in6_ifaddrhead); 182 V_in6_ifaddrhashtbl = hashinit(IN6ADDR_NHASH, M_IFADDR, 183 &V_in6_ifaddrhmask); 184 185 /* Initialize packet filter hooks. */ 186 V_inet6_pfil_hook.ph_type = PFIL_TYPE_AF; 187 V_inet6_pfil_hook.ph_af = AF_INET6; 188 if ((i = pfil_head_register(&V_inet6_pfil_hook)) != 0) 189 printf("%s: WARNING: unable to register pfil hook, " 190 "error %d\n", __func__, i); 191 192 scope6_init(); 193 addrsel_policy_init(); 194 nd6_init(); 195 frag6_init(); 196 197#ifdef FLOWTABLE 198 if (TUNABLE_INT_FETCH("net.inet6.ip6.output_flowtable_size", 199 &V_ip6_output_flowtable_size)) { 200 if (V_ip6_output_flowtable_size < 256) 201 V_ip6_output_flowtable_size = 256; 202 if (!powerof2(V_ip6_output_flowtable_size)) { 203 printf("flowtable must be power of 2 size\n"); 204 V_ip6_output_flowtable_size = 2048; 205 } 206 } else { 207 /* 208 * round up to the next power of 2 209 */ 210 V_ip6_output_flowtable_size = 1 << fls((1024 + maxusers * 64)-1); 211 } 212 V_ip6_ft = flowtable_alloc("ipv6", V_ip6_output_flowtable_size, FL_IPV6|FL_PCPU); 213#endif 214 215 V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR; 216 217 /* Skip global initialization stuff for non-default instances. */ 218 if (!IS_DEFAULT_VNET(curvnet)) 219 return; 220 221#ifdef DIAGNOSTIC 222 if (sizeof(struct protosw) != sizeof(struct ip6protosw)) 223 panic("sizeof(protosw) != sizeof(ip6protosw)"); 224#endif 225 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 226 if (pr == NULL) 227 panic("ip6_init"); 228 229 /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */ 230 for (i = 0; i < IPPROTO_MAX; i++) 231 ip6_protox[i] = pr - inet6sw; 232 /* 233 * Cycle through IP protocols and put them into the appropriate place 234 * in ip6_protox[]. 235 */ 236 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 237 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 238 if (pr->pr_domain->dom_family == PF_INET6 && 239 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) { 240 /* Be careful to only index valid IP protocols. */ 241 if (pr->pr_protocol < IPPROTO_MAX) 242 ip6_protox[pr->pr_protocol] = pr - inet6sw; 243 } 244 245 netisr_register(&ip6_nh); 246} 247 248/* 249 * The protocol to be inserted into ip6_protox[] must be already registered 250 * in inet6sw[], either statically or through pf_proto_register(). 251 */ 252int 253ip6proto_register(short ip6proto) 254{ 255 struct ip6protosw *pr; 256 257 /* Sanity checks. */ 258 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 259 return (EPROTONOSUPPORT); 260 261 /* 262 * The protocol slot must not be occupied by another protocol 263 * already. An index pointing to IPPROTO_RAW is unused. 264 */ 265 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 266 if (pr == NULL) 267 return (EPFNOSUPPORT); 268 if (ip6_protox[ip6proto] != pr - inet6sw) /* IPPROTO_RAW */ 269 return (EEXIST); 270 271 /* 272 * Find the protocol position in inet6sw[] and set the index. 273 */ 274 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 275 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) { 276 if (pr->pr_domain->dom_family == PF_INET6 && 277 pr->pr_protocol && pr->pr_protocol == ip6proto) { 278 ip6_protox[pr->pr_protocol] = pr - inet6sw; 279 return (0); 280 } 281 } 282 return (EPROTONOSUPPORT); 283} 284 285int 286ip6proto_unregister(short ip6proto) 287{ 288 struct ip6protosw *pr; 289 290 /* Sanity checks. */ 291 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 292 return (EPROTONOSUPPORT); 293 294 /* Check if the protocol was indeed registered. */ 295 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 296 if (pr == NULL) 297 return (EPFNOSUPPORT); 298 if (ip6_protox[ip6proto] == pr - inet6sw) /* IPPROTO_RAW */ 299 return (ENOENT); 300 301 /* Reset the protocol slot to IPPROTO_RAW. */ 302 ip6_protox[ip6proto] = pr - inet6sw; 303 return (0); 304} 305 306#ifdef VIMAGE 307void 308ip6_destroy() 309{ 310 int i; 311 312 if ((i = pfil_head_unregister(&V_inet6_pfil_hook)) != 0) 313 printf("%s: WARNING: unable to unregister pfil hook, " 314 "error %d\n", __func__, i); 315 hashdestroy(V_in6_ifaddrhashtbl, M_IFADDR, V_in6_ifaddrhmask); 316 nd6_destroy(); 317 callout_drain(&V_in6_tmpaddrtimer_ch); 318} 319#endif 320 321static int 322ip6_init2_vnet(const void *unused __unused) 323{ 324 325 /* nd6_timer_init */ 326 callout_init(&V_nd6_timer_ch, 0); 327 callout_reset(&V_nd6_timer_ch, hz, nd6_timer, curvnet); 328 329 /* timer for regeneranation of temporary addresses randomize ID */ 330 callout_init(&V_in6_tmpaddrtimer_ch, 0); 331 callout_reset(&V_in6_tmpaddrtimer_ch, 332 (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor - 333 V_ip6_temp_regen_advance) * hz, 334 in6_tmpaddrtimer, curvnet); 335 336 return (0); 337} 338 339static void 340ip6_init2(void *dummy) 341{ 342 343 ip6_init2_vnet(NULL); 344} 345 346/* cheat */ 347/* This must be after route_init(), which is now SI_ORDER_THIRD */ 348SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL); 349 350static int 351ip6_input_hbh(struct mbuf *m, uint32_t *plen, uint32_t *rtalert, int *off, 352 int *nxt, int *ours) 353{ 354 struct ip6_hdr *ip6; 355 struct ip6_hbh *hbh; 356 357 if (ip6_hopopts_input(plen, rtalert, &m, off)) { 358#if 0 /*touches NULL pointer*/ 359 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 360#endif 361 goto out; /* m have already been freed */ 362 } 363 364 /* adjust pointer */ 365 ip6 = mtod(m, struct ip6_hdr *); 366 367 /* 368 * if the payload length field is 0 and the next header field 369 * indicates Hop-by-Hop Options header, then a Jumbo Payload 370 * option MUST be included. 371 */ 372 if (ip6->ip6_plen == 0 && *plen == 0) { 373 /* 374 * Note that if a valid jumbo payload option is 375 * contained, ip6_hopopts_input() must set a valid 376 * (non-zero) payload length to the variable plen. 377 */ 378 IP6STAT_INC(ip6s_badoptions); 379 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 380 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 381 icmp6_error(m, ICMP6_PARAM_PROB, 382 ICMP6_PARAMPROB_HEADER, 383 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 384 goto out; 385 } 386#ifndef PULLDOWN_TEST 387 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 388 hbh = (struct ip6_hbh *)(ip6 + 1); 389#else 390 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 391 sizeof(struct ip6_hbh)); 392 if (hbh == NULL) { 393 IP6STAT_INC(ip6s_tooshort); 394 goto out; 395 } 396#endif 397 *nxt = hbh->ip6h_nxt; 398 399 /* 400 * If we are acting as a router and the packet contains a 401 * router alert option, see if we know the option value. 402 * Currently, we only support the option value for MLD, in which 403 * case we should pass the packet to the multicast routing 404 * daemon. 405 */ 406 if (*rtalert != ~0) { 407 switch (*rtalert) { 408 case IP6OPT_RTALERT_MLD: 409 if (V_ip6_forwarding) 410 *ours = 1; 411 break; 412 default: 413 /* 414 * RFC2711 requires unrecognized values must be 415 * silently ignored. 416 */ 417 break; 418 } 419 } 420 421 return (0); 422 423out: 424 return (1); 425} 426 427void 428ip6_input(struct mbuf *m) 429{ 430 struct ip6_hdr *ip6; 431 int off = sizeof(struct ip6_hdr), nest; 432 u_int32_t plen; 433 u_int32_t rtalert = ~0; 434 int nxt, ours = 0; 435 struct ifnet *deliverifp = NULL, *ifp = NULL; 436 struct in6_addr odst; 437 struct route_in6 rin6; 438 int srcrt = 0; 439 struct llentry *lle = NULL; 440 struct sockaddr_in6 dst6, *dst; 441 442 bzero(&rin6, sizeof(struct route_in6)); 443#ifdef IPSEC 444 /* 445 * should the inner packet be considered authentic? 446 * see comment in ah4_input(). 447 * NB: m cannot be NULL when passed to the input routine 448 */ 449 450 m->m_flags &= ~M_AUTHIPHDR; 451 m->m_flags &= ~M_AUTHIPDGM; 452 453#endif /* IPSEC */ 454 455 /* 456 * make sure we don't have onion peering information into m_tag. 457 */ 458 ip6_delaux(m); 459 460 if (m->m_flags & M_FASTFWD_OURS) { 461 /* 462 * Firewall changed destination to local. 463 */ 464 m->m_flags &= ~M_FASTFWD_OURS; 465 ours = 1; 466 deliverifp = m->m_pkthdr.rcvif; 467 ip6 = mtod(m, struct ip6_hdr *); 468 goto hbhcheck; 469 } 470 471 /* 472 * mbuf statistics 473 */ 474 if (m->m_flags & M_EXT) { 475 if (m->m_next) 476 IP6STAT_INC(ip6s_mext2m); 477 else 478 IP6STAT_INC(ip6s_mext1); 479 } else { 480 if (m->m_next) { 481 if (m->m_flags & M_LOOP) { 482 IP6STAT_INC(ip6s_m2m[V_loif->if_index]); 483 } else if (m->m_pkthdr.rcvif->if_index < IP6S_M2MMAX) 484 IP6STAT_INC( 485 ip6s_m2m[m->m_pkthdr.rcvif->if_index]); 486 else 487 IP6STAT_INC(ip6s_m2m[0]); 488 } else 489 IP6STAT_INC(ip6s_m1); 490 } 491 492 /* drop the packet if IPv6 operation is disabled on the IF */ 493 if ((ND_IFINFO(m->m_pkthdr.rcvif)->flags & ND6_IFF_IFDISABLED)) { 494 m_freem(m); 495 return; 496 } 497 498 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 499 IP6STAT_INC(ip6s_total); 500 501#ifndef PULLDOWN_TEST 502 /* 503 * L2 bridge code and some other code can return mbuf chain 504 * that does not conform to KAME requirement. too bad. 505 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? 506 */ 507 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { 508 struct mbuf *n; 509 510 if (m->m_pkthdr.len > MHLEN) 511 n = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 512 else 513 n = m_gethdr(M_NOWAIT, MT_DATA); 514 if (n == NULL) { 515 m_freem(m); 516 return; /* ENOBUFS */ 517 } 518 519 m_move_pkthdr(n, m); 520 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t)); 521 n->m_len = n->m_pkthdr.len; 522 m_freem(m); 523 m = n; 524 } 525 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */); 526#endif 527 528 if (m->m_len < sizeof(struct ip6_hdr)) { 529 struct ifnet *inifp; 530 inifp = m->m_pkthdr.rcvif; 531 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 532 IP6STAT_INC(ip6s_toosmall); 533 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 534 return; 535 } 536 } 537 538 ip6 = mtod(m, struct ip6_hdr *); 539 540 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 541 IP6STAT_INC(ip6s_badvers); 542 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 543 goto bad; 544 } 545 546 IP6STAT_INC(ip6s_nxthist[ip6->ip6_nxt]); 547 548 IP_PROBE(receive, NULL, NULL, ip6, m->m_pkthdr.rcvif, NULL, ip6); 549 550 /* 551 * Check against address spoofing/corruption. 552 */ 553 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 554 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 555 /* 556 * XXX: "badscope" is not very suitable for a multicast source. 557 */ 558 IP6STAT_INC(ip6s_badscope); 559 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 560 goto bad; 561 } 562 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && 563 !(m->m_flags & M_LOOP)) { 564 /* 565 * In this case, the packet should come from the loopback 566 * interface. However, we cannot just check the if_flags, 567 * because ip6_mloopback() passes the "actual" interface 568 * as the outgoing/incoming interface. 569 */ 570 IP6STAT_INC(ip6s_badscope); 571 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 572 goto bad; 573 } 574 575#ifdef ALTQ 576 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 577 /* packet is dropped by traffic conditioner */ 578 return; 579 } 580#endif 581 /* 582 * The following check is not documented in specs. A malicious 583 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 584 * and bypass security checks (act as if it was from 127.0.0.1 by using 585 * IPv6 src ::ffff:127.0.0.1). Be cautious. 586 * 587 * This check chokes if we are in an SIIT cloud. As none of BSDs 588 * support IPv4-less kernel compilation, we cannot support SIIT 589 * environment at all. So, it makes more sense for us to reject any 590 * malicious packets for non-SIIT environment, than try to do a 591 * partial support for SIIT environment. 592 */ 593 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 594 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 595 IP6STAT_INC(ip6s_badscope); 596 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 597 goto bad; 598 } 599#if 0 600 /* 601 * Reject packets with IPv4 compatible addresses (auto tunnel). 602 * 603 * The code forbids auto tunnel relay case in RFC1933 (the check is 604 * stronger than RFC1933). We may want to re-enable it if mech-xx 605 * is revised to forbid relaying case. 606 */ 607 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 608 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 609 IP6STAT_INC(ip6s_badscope); 610 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 611 goto bad; 612 } 613#endif 614#ifdef IPSEC 615 /* 616 * Bypass packet filtering for packets previously handled by IPsec. 617 */ 618 if (ip6_ipsec_filtertunnel(m)) 619 goto passin; 620#endif /* IPSEC */ 621 622 /* 623 * Run through list of hooks for input packets. 624 * 625 * NB: Beware of the destination address changing 626 * (e.g. by NAT rewriting). When this happens, 627 * tell ip6_forward to do the right thing. 628 */ 629 odst = ip6->ip6_dst; 630 631 /* Jump over all PFIL processing if hooks are not active. */ 632 if (!PFIL_HOOKED(&V_inet6_pfil_hook)) 633 goto passin; 634 635 if (pfil_run_hooks(&V_inet6_pfil_hook, &m, 636 m->m_pkthdr.rcvif, PFIL_IN, NULL)) 637 return; 638 if (m == NULL) /* consumed by filter */ 639 return; 640 ip6 = mtod(m, struct ip6_hdr *); 641 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 642 643 if (m->m_flags & M_FASTFWD_OURS) { 644 m->m_flags &= ~M_FASTFWD_OURS; 645 ours = 1; 646 deliverifp = m->m_pkthdr.rcvif; 647 goto hbhcheck; 648 } 649 if ((m->m_flags & M_IP6_NEXTHOP) && 650 m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) { 651 /* 652 * Directly ship the packet on. This allows forwarding 653 * packets originally destined to us to some other directly 654 * connected host. 655 */ 656 ip6_forward(m, 1); 657 goto out; 658 } 659 660passin: 661 /* 662 * Disambiguate address scope zones (if there is ambiguity). 663 * We first make sure that the original source or destination address 664 * is not in our internal form for scoped addresses. Such addresses 665 * are not necessarily invalid spec-wise, but we cannot accept them due 666 * to the usage conflict. 667 * in6_setscope() then also checks and rejects the cases where src or 668 * dst are the loopback address and the receiving interface 669 * is not loopback. 670 */ 671 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) { 672 IP6STAT_INC(ip6s_badscope); /* XXX */ 673 goto bad; 674 } 675 if (in6_setscope(&ip6->ip6_src, m->m_pkthdr.rcvif, NULL) || 676 in6_setscope(&ip6->ip6_dst, m->m_pkthdr.rcvif, NULL)) { 677 IP6STAT_INC(ip6s_badscope); 678 goto bad; 679 } 680 681 /* 682 * Multicast check. Assume packet is for us to avoid 683 * prematurely taking locks. 684 */ 685 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 686 ours = 1; 687 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 688 deliverifp = m->m_pkthdr.rcvif; 689 goto hbhcheck; 690 } 691 692 /* 693 * Unicast check 694 */ 695 696 bzero(&dst6, sizeof(dst6)); 697 dst6.sin6_family = AF_INET6; 698 dst6.sin6_len = sizeof(struct sockaddr_in6); 699 dst6.sin6_addr = ip6->ip6_dst; 700 ifp = m->m_pkthdr.rcvif; 701 IF_AFDATA_RLOCK(ifp); 702 lle = lla_lookup(LLTABLE6(ifp), 0, 703 (struct sockaddr *)&dst6); 704 IF_AFDATA_RUNLOCK(ifp); 705 if ((lle != NULL) && (lle->la_flags & LLE_IFADDR)) { 706 struct ifaddr *ifa; 707 struct in6_ifaddr *ia6; 708 int bad; 709 710 bad = 1; 711#define sa_equal(a1, a2) \ 712 (bcmp((a1), (a2), ((a1))->sin6_len) == 0) 713 IF_ADDR_RLOCK(ifp); 714 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 715 if (ifa->ifa_addr->sa_family != dst6.sin6_family) 716 continue; 717 if (sa_equal(&dst6, ifa->ifa_addr)) 718 break; 719 } 720 KASSERT(ifa != NULL, ("%s: ifa not found for lle %p", 721 __func__, lle)); 722#undef sa_equal 723 724 ia6 = (struct in6_ifaddr *)ifa; 725 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 726 /* Count the packet in the ip address stats */ 727 ia6->ia_ifa.if_ipackets++; 728 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len; 729 730 /* 731 * record address information into m_tag. 732 */ 733 (void)ip6_setdstifaddr(m, ia6); 734 735 bad = 0; 736 } else { 737 char ip6bufs[INET6_ADDRSTRLEN]; 738 char ip6bufd[INET6_ADDRSTRLEN]; 739 /* address is not ready, so discard the packet. */ 740 nd6log((LOG_INFO, 741 "ip6_input: packet to an unready address %s->%s\n", 742 ip6_sprintf(ip6bufs, &ip6->ip6_src), 743 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 744 } 745 IF_ADDR_RUNLOCK(ifp); 746 LLE_RUNLOCK(lle); 747 if (bad) 748 goto bad; 749 else { 750 ours = 1; 751 deliverifp = ifp; 752 goto hbhcheck; 753 } 754 } 755 if (lle != NULL) 756 LLE_RUNLOCK(lle); 757 758 dst = &rin6.ro_dst; 759 dst->sin6_len = sizeof(struct sockaddr_in6); 760 dst->sin6_family = AF_INET6; 761 dst->sin6_addr = ip6->ip6_dst; 762 rin6.ro_rt = in6_rtalloc1((struct sockaddr *)dst, 0, 0, M_GETFIB(m)); 763 if (rin6.ro_rt) 764 RT_UNLOCK(rin6.ro_rt); 765 766#define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 767 768 /* 769 * Accept the packet if the forwarding interface to the destination 770 * according to the routing table is the loopback interface, 771 * unless the associated route has a gateway. 772 * Note that this approach causes to accept a packet if there is a 773 * route to the loopback interface for the destination of the packet. 774 * But we think it's even useful in some situations, e.g. when using 775 * a special daemon which wants to intercept the packet. 776 * 777 * XXX: some OSes automatically make a cloned route for the destination 778 * of an outgoing packet. If the outgoing interface of the packet 779 * is a loopback one, the kernel would consider the packet to be 780 * accepted, even if we have no such address assinged on the interface. 781 * We check the cloned flag of the route entry to reject such cases, 782 * assuming that route entries for our own addresses are not made by 783 * cloning (it should be true because in6_addloop explicitly installs 784 * the host route). However, we might have to do an explicit check 785 * while it would be less efficient. Or, should we rather install a 786 * reject route for such a case? 787 */ 788 if (rin6.ro_rt && 789 (rin6.ro_rt->rt_flags & 790 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 791#ifdef RTF_WASCLONED 792 !(rin6.ro_rt->rt_flags & RTF_WASCLONED) && 793#endif 794#ifdef RTF_CLONED 795 !(rin6.ro_rt->rt_flags & RTF_CLONED) && 796#endif 797#if 0 798 /* 799 * The check below is redundant since the comparison of 800 * the destination and the key of the rtentry has 801 * already done through looking up the routing table. 802 */ 803 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 804 &rt6_key(rin6.ro_rt)->sin6_addr) 805#endif 806 rin6.ro_rt->rt_ifp->if_type == IFT_LOOP) { 807 int free_ia6 = 0; 808 struct in6_ifaddr *ia6; 809 810 /* 811 * found the loopback route to the interface address 812 */ 813 if (rin6.ro_rt->rt_gateway->sa_family == AF_LINK) { 814 struct sockaddr_in6 dest6; 815 816 bzero(&dest6, sizeof(dest6)); 817 dest6.sin6_family = AF_INET6; 818 dest6.sin6_len = sizeof(dest6); 819 dest6.sin6_addr = ip6->ip6_dst; 820 ia6 = (struct in6_ifaddr *) 821 ifa_ifwithaddr((struct sockaddr *)&dest6); 822 if (ia6 == NULL) 823 goto bad; 824 free_ia6 = 1; 825 } 826 else 827 ia6 = (struct in6_ifaddr *)rin6.ro_rt->rt_ifa; 828 829 /* 830 * record address information into m_tag. 831 */ 832 (void)ip6_setdstifaddr(m, ia6); 833 834 /* 835 * packets to a tentative, duplicated, or somehow invalid 836 * address must not be accepted. 837 */ 838 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 839 /* this address is ready */ 840 ours = 1; 841 deliverifp = ia6->ia_ifp; /* correct? */ 842 /* Count the packet in the ip address stats */ 843 ia6->ia_ifa.if_ipackets++; 844 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len; 845 if (ia6 != NULL && free_ia6 != 0) 846 ifa_free(&ia6->ia_ifa); 847 goto hbhcheck; 848 } else { 849 char ip6bufs[INET6_ADDRSTRLEN]; 850 char ip6bufd[INET6_ADDRSTRLEN]; 851 /* address is not ready, so discard the packet. */ 852 nd6log((LOG_INFO, 853 "ip6_input: packet to an unready address %s->%s\n", 854 ip6_sprintf(ip6bufs, &ip6->ip6_src), 855 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 856 857 if (ia6 != NULL && free_ia6 != 0) 858 ifa_free(&ia6->ia_ifa); 859 goto bad; 860 } 861 } 862 863 /* 864 * FAITH (Firewall Aided Internet Translator) 865 */ 866 if (V_ip6_keepfaith) { 867 if (rin6.ro_rt && rin6.ro_rt->rt_ifp && 868 rin6.ro_rt->rt_ifp->if_type == IFT_FAITH) { 869 /* XXX do we need more sanity checks? */ 870 ours = 1; 871 deliverifp = rin6.ro_rt->rt_ifp; /* faith */ 872 goto hbhcheck; 873 } 874 } 875 876 /* 877 * Now there is no reason to process the packet if it's not our own 878 * and we're not a router. 879 */ 880 if (!V_ip6_forwarding) { 881 IP6STAT_INC(ip6s_cantforward); 882 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 883 goto bad; 884 } 885 886 hbhcheck: 887 /* 888 * record address information into m_tag, if we don't have one yet. 889 * note that we are unable to record it, if the address is not listed 890 * as our interface address (e.g. multicast addresses, addresses 891 * within FAITH prefixes and such). 892 */ 893 if (deliverifp) { 894 struct in6_ifaddr *ia6; 895 896 if ((ia6 = ip6_getdstifaddr(m)) != NULL) { 897 ifa_free(&ia6->ia_ifa); 898 } else { 899 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 900 if (ia6) { 901 if (!ip6_setdstifaddr(m, ia6)) { 902 /* 903 * XXX maybe we should drop the packet here, 904 * as we could not provide enough information 905 * to the upper layers. 906 */ 907 } 908 ifa_free(&ia6->ia_ifa); 909 } 910 } 911 } 912 913 /* 914 * Process Hop-by-Hop options header if it's contained. 915 * m may be modified in ip6_hopopts_input(). 916 * If a JumboPayload option is included, plen will also be modified. 917 */ 918 plen = (u_int32_t)ntohs(ip6->ip6_plen); 919 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 920 int error; 921 922 error = ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours); 923 if (error != 0) 924 goto out; 925 } else 926 nxt = ip6->ip6_nxt; 927 928 /* 929 * Check that the amount of data in the buffers 930 * is as at least much as the IPv6 header would have us expect. 931 * Trim mbufs if longer than we expect. 932 * Drop packet if shorter than we expect. 933 */ 934 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 935 IP6STAT_INC(ip6s_tooshort); 936 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 937 goto bad; 938 } 939 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 940 if (m->m_len == m->m_pkthdr.len) { 941 m->m_len = sizeof(struct ip6_hdr) + plen; 942 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 943 } else 944 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 945 } 946 947 /* 948 * Forward if desirable. 949 */ 950 if (V_ip6_mrouter && 951 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 952 /* 953 * If we are acting as a multicast router, all 954 * incoming multicast packets are passed to the 955 * kernel-level multicast forwarding function. 956 * The packet is returned (relatively) intact; if 957 * ip6_mforward() returns a non-zero value, the packet 958 * must be discarded, else it may be accepted below. 959 * 960 * XXX TODO: Check hlim and multicast scope here to avoid 961 * unnecessarily calling into ip6_mforward(). 962 */ 963 if (ip6_mforward && 964 ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 965 IP6STAT_INC(ip6s_cantforward); 966 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 967 goto bad; 968 } 969 } else if (!ours) { 970 ip6_forward(m, srcrt); 971 goto out; 972 } 973 974 ip6 = mtod(m, struct ip6_hdr *); 975 976 /* 977 * Malicious party may be able to use IPv4 mapped addr to confuse 978 * tcp/udp stack and bypass security checks (act as if it was from 979 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 980 * 981 * For SIIT end node behavior, you may want to disable the check. 982 * However, you will become vulnerable to attacks using IPv4 mapped 983 * source. 984 */ 985 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 986 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 987 IP6STAT_INC(ip6s_badscope); 988 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 989 goto bad; 990 } 991 992 /* 993 * Tell launch routine the next header 994 */ 995 IP6STAT_INC(ip6s_delivered); 996 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 997 nest = 0; 998 999 while (nxt != IPPROTO_DONE) { 1000 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 1001 IP6STAT_INC(ip6s_toomanyhdr); 1002 goto bad; 1003 } 1004 1005 /* 1006 * protection against faulty packet - there should be 1007 * more sanity checks in header chain processing. 1008 */ 1009 if (m->m_pkthdr.len < off) { 1010 IP6STAT_INC(ip6s_tooshort); 1011 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 1012 goto bad; 1013 } 1014 1015#ifdef IPSEC 1016 /* 1017 * enforce IPsec policy checking if we are seeing last header. 1018 * note that we do not visit this with protocols with pcb layer 1019 * code - like udp/tcp/raw ip. 1020 */ 1021 if (ip6_ipsec_input(m, nxt)) 1022 goto bad; 1023#endif /* IPSEC */ 1024 1025 /* 1026 * Use mbuf flags to propagate Router Alert option to 1027 * ICMPv6 layer, as hop-by-hop options have been stripped. 1028 */ 1029 if (nxt == IPPROTO_ICMPV6 && rtalert != ~0) 1030 m->m_flags |= M_RTALERT_MLD; 1031 1032 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 1033 } 1034 goto out; 1035bad: 1036 m_freem(m); 1037out: 1038 if (rin6.ro_rt) 1039 RTFREE(rin6.ro_rt); 1040} 1041 1042/* 1043 * set/grab in6_ifaddr correspond to IPv6 destination address. 1044 * XXX backward compatibility wrapper 1045 * 1046 * XXXRW: We should bump the refcount on ia6 before sticking it in the m_tag, 1047 * and then bump it when the tag is copied, and release it when the tag is 1048 * freed. Unfortunately, m_tags don't support deep copies (yet), so instead 1049 * we just bump the ia refcount when we receive it. This should be fixed. 1050 */ 1051static struct ip6aux * 1052ip6_setdstifaddr(struct mbuf *m, struct in6_ifaddr *ia6) 1053{ 1054 struct ip6aux *ip6a; 1055 1056 ip6a = ip6_addaux(m); 1057 if (ip6a) 1058 ip6a->ip6a_dstia6 = ia6; 1059 return ip6a; /* NULL if failed to set */ 1060} 1061 1062struct in6_ifaddr * 1063ip6_getdstifaddr(struct mbuf *m) 1064{ 1065 struct ip6aux *ip6a; 1066 struct in6_ifaddr *ia; 1067 1068 ip6a = ip6_findaux(m); 1069 if (ip6a) { 1070 ia = ip6a->ip6a_dstia6; 1071 ifa_ref(&ia->ia_ifa); 1072 return ia; 1073 } else 1074 return NULL; 1075} 1076 1077/* 1078 * Hop-by-Hop options header processing. If a valid jumbo payload option is 1079 * included, the real payload length will be stored in plenp. 1080 * 1081 * rtalertp - XXX: should be stored more smart way 1082 */ 1083static int 1084ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp, 1085 struct mbuf **mp, int *offp) 1086{ 1087 struct mbuf *m = *mp; 1088 int off = *offp, hbhlen; 1089 struct ip6_hbh *hbh; 1090 u_int8_t *opt; 1091 1092 /* validation of the length of the header */ 1093#ifndef PULLDOWN_TEST 1094 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 1095 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 1096 hbhlen = (hbh->ip6h_len + 1) << 3; 1097 1098 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 1099 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 1100#else 1101 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1102 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1103 if (hbh == NULL) { 1104 IP6STAT_INC(ip6s_tooshort); 1105 return -1; 1106 } 1107 hbhlen = (hbh->ip6h_len + 1) << 3; 1108 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 1109 hbhlen); 1110 if (hbh == NULL) { 1111 IP6STAT_INC(ip6s_tooshort); 1112 return -1; 1113 } 1114#endif 1115 off += hbhlen; 1116 hbhlen -= sizeof(struct ip6_hbh); 1117 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 1118 1119 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 1120 hbhlen, rtalertp, plenp) < 0) 1121 return (-1); 1122 1123 *offp = off; 1124 *mp = m; 1125 return (0); 1126} 1127 1128/* 1129 * Search header for all Hop-by-hop options and process each option. 1130 * This function is separate from ip6_hopopts_input() in order to 1131 * handle a case where the sending node itself process its hop-by-hop 1132 * options header. In such a case, the function is called from ip6_output(). 1133 * 1134 * The function assumes that hbh header is located right after the IPv6 header 1135 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 1136 * opthead + hbhlen is located in contiguous memory region. 1137 */ 1138int 1139ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 1140 u_int32_t *rtalertp, u_int32_t *plenp) 1141{ 1142 struct ip6_hdr *ip6; 1143 int optlen = 0; 1144 u_int8_t *opt = opthead; 1145 u_int16_t rtalert_val; 1146 u_int32_t jumboplen; 1147 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 1148 1149 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 1150 switch (*opt) { 1151 case IP6OPT_PAD1: 1152 optlen = 1; 1153 break; 1154 case IP6OPT_PADN: 1155 if (hbhlen < IP6OPT_MINLEN) { 1156 IP6STAT_INC(ip6s_toosmall); 1157 goto bad; 1158 } 1159 optlen = *(opt + 1) + 2; 1160 break; 1161 case IP6OPT_ROUTER_ALERT: 1162 /* XXX may need check for alignment */ 1163 if (hbhlen < IP6OPT_RTALERT_LEN) { 1164 IP6STAT_INC(ip6s_toosmall); 1165 goto bad; 1166 } 1167 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 1168 /* XXX stat */ 1169 icmp6_error(m, ICMP6_PARAM_PROB, 1170 ICMP6_PARAMPROB_HEADER, 1171 erroff + opt + 1 - opthead); 1172 return (-1); 1173 } 1174 optlen = IP6OPT_RTALERT_LEN; 1175 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 1176 *rtalertp = ntohs(rtalert_val); 1177 break; 1178 case IP6OPT_JUMBO: 1179 /* XXX may need check for alignment */ 1180 if (hbhlen < IP6OPT_JUMBO_LEN) { 1181 IP6STAT_INC(ip6s_toosmall); 1182 goto bad; 1183 } 1184 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 1185 /* XXX stat */ 1186 icmp6_error(m, ICMP6_PARAM_PROB, 1187 ICMP6_PARAMPROB_HEADER, 1188 erroff + opt + 1 - opthead); 1189 return (-1); 1190 } 1191 optlen = IP6OPT_JUMBO_LEN; 1192 1193 /* 1194 * IPv6 packets that have non 0 payload length 1195 * must not contain a jumbo payload option. 1196 */ 1197 ip6 = mtod(m, struct ip6_hdr *); 1198 if (ip6->ip6_plen) { 1199 IP6STAT_INC(ip6s_badoptions); 1200 icmp6_error(m, ICMP6_PARAM_PROB, 1201 ICMP6_PARAMPROB_HEADER, 1202 erroff + opt - opthead); 1203 return (-1); 1204 } 1205 1206 /* 1207 * We may see jumbolen in unaligned location, so 1208 * we'd need to perform bcopy(). 1209 */ 1210 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 1211 jumboplen = (u_int32_t)htonl(jumboplen); 1212 1213#if 1 1214 /* 1215 * if there are multiple jumbo payload options, 1216 * *plenp will be non-zero and the packet will be 1217 * rejected. 1218 * the behavior may need some debate in ipngwg - 1219 * multiple options does not make sense, however, 1220 * there's no explicit mention in specification. 1221 */ 1222 if (*plenp != 0) { 1223 IP6STAT_INC(ip6s_badoptions); 1224 icmp6_error(m, ICMP6_PARAM_PROB, 1225 ICMP6_PARAMPROB_HEADER, 1226 erroff + opt + 2 - opthead); 1227 return (-1); 1228 } 1229#endif 1230 1231 /* 1232 * jumbo payload length must be larger than 65535. 1233 */ 1234 if (jumboplen <= IPV6_MAXPACKET) { 1235 IP6STAT_INC(ip6s_badoptions); 1236 icmp6_error(m, ICMP6_PARAM_PROB, 1237 ICMP6_PARAMPROB_HEADER, 1238 erroff + opt + 2 - opthead); 1239 return (-1); 1240 } 1241 *plenp = jumboplen; 1242 1243 break; 1244 default: /* unknown option */ 1245 if (hbhlen < IP6OPT_MINLEN) { 1246 IP6STAT_INC(ip6s_toosmall); 1247 goto bad; 1248 } 1249 optlen = ip6_unknown_opt(opt, m, 1250 erroff + opt - opthead); 1251 if (optlen == -1) 1252 return (-1); 1253 optlen += 2; 1254 break; 1255 } 1256 } 1257 1258 return (0); 1259 1260 bad: 1261 m_freem(m); 1262 return (-1); 1263} 1264 1265/* 1266 * Unknown option processing. 1267 * The third argument `off' is the offset from the IPv6 header to the option, 1268 * which is necessary if the IPv6 header the and option header and IPv6 header 1269 * is not contiguous in order to return an ICMPv6 error. 1270 */ 1271int 1272ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 1273{ 1274 struct ip6_hdr *ip6; 1275 1276 switch (IP6OPT_TYPE(*optp)) { 1277 case IP6OPT_TYPE_SKIP: /* ignore the option */ 1278 return ((int)*(optp + 1)); 1279 case IP6OPT_TYPE_DISCARD: /* silently discard */ 1280 m_freem(m); 1281 return (-1); 1282 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 1283 IP6STAT_INC(ip6s_badoptions); 1284 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 1285 return (-1); 1286 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 1287 IP6STAT_INC(ip6s_badoptions); 1288 ip6 = mtod(m, struct ip6_hdr *); 1289 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 1290 (m->m_flags & (M_BCAST|M_MCAST))) 1291 m_freem(m); 1292 else 1293 icmp6_error(m, ICMP6_PARAM_PROB, 1294 ICMP6_PARAMPROB_OPTION, off); 1295 return (-1); 1296 } 1297 1298 m_freem(m); /* XXX: NOTREACHED */ 1299 return (-1); 1300} 1301 1302/* 1303 * Create the "control" list for this pcb. 1304 * These functions will not modify mbuf chain at all. 1305 * 1306 * With KAME mbuf chain restriction: 1307 * The routine will be called from upper layer handlers like tcp6_input(). 1308 * Thus the routine assumes that the caller (tcp6_input) have already 1309 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1310 * very first mbuf on the mbuf chain. 1311 * 1312 * ip6_savecontrol_v4 will handle those options that are possible to be 1313 * set on a v4-mapped socket. 1314 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those 1315 * options and handle the v6-only ones itself. 1316 */ 1317struct mbuf ** 1318ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp, 1319 int *v4only) 1320{ 1321 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1322 1323#ifdef SO_TIMESTAMP 1324 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) { 1325 struct timeval tv; 1326 1327 microtime(&tv); 1328 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1329 SCM_TIMESTAMP, SOL_SOCKET); 1330 if (*mp) 1331 mp = &(*mp)->m_next; 1332 } 1333#endif 1334 1335#define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y)) 1336 /* RFC 2292 sec. 5 */ 1337 if ((inp->inp_flags & IN6P_PKTINFO) != 0) { 1338 struct in6_pktinfo pi6; 1339 1340 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1341#ifdef INET 1342 struct ip *ip; 1343 1344 ip = mtod(m, struct ip *); 1345 pi6.ipi6_addr.s6_addr32[0] = 0; 1346 pi6.ipi6_addr.s6_addr32[1] = 0; 1347 pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP; 1348 pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr; 1349#else 1350 /* We won't hit this code */ 1351 bzero(&pi6.ipi6_addr, sizeof(struct in6_addr)); 1352#endif 1353 } else { 1354 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1355 in6_clearscope(&pi6.ipi6_addr); /* XXX */ 1356 } 1357 pi6.ipi6_ifindex = 1358 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0; 1359 1360 *mp = sbcreatecontrol((caddr_t) &pi6, 1361 sizeof(struct in6_pktinfo), 1362 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6); 1363 if (*mp) 1364 mp = &(*mp)->m_next; 1365 } 1366 1367 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) { 1368 int hlim; 1369 1370 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1371#ifdef INET 1372 struct ip *ip; 1373 1374 ip = mtod(m, struct ip *); 1375 hlim = ip->ip_ttl; 1376#else 1377 /* We won't hit this code */ 1378 hlim = 0; 1379#endif 1380 } else { 1381 hlim = ip6->ip6_hlim & 0xff; 1382 } 1383 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 1384 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), 1385 IPPROTO_IPV6); 1386 if (*mp) 1387 mp = &(*mp)->m_next; 1388 } 1389 1390 if ((inp->inp_flags & IN6P_TCLASS) != 0) { 1391 int tclass; 1392 1393 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1394#ifdef INET 1395 struct ip *ip; 1396 1397 ip = mtod(m, struct ip *); 1398 tclass = ip->ip_tos; 1399#else 1400 /* We won't hit this code */ 1401 tclass = 0; 1402#endif 1403 } else { 1404 u_int32_t flowinfo; 1405 1406 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1407 flowinfo >>= 20; 1408 tclass = flowinfo & 0xff; 1409 } 1410 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int), 1411 IPV6_TCLASS, IPPROTO_IPV6); 1412 if (*mp) 1413 mp = &(*mp)->m_next; 1414 } 1415 1416 if (v4only != NULL) { 1417 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1418 *v4only = 1; 1419 } else { 1420 *v4only = 0; 1421 } 1422 } 1423 1424 return (mp); 1425} 1426 1427void 1428ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 1429{ 1430 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1431 int v4only = 0; 1432 1433 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only); 1434 if (v4only) 1435 return; 1436 1437 /* 1438 * IPV6_HOPOPTS socket option. Recall that we required super-user 1439 * privilege for the option (see ip6_ctloutput), but it might be too 1440 * strict, since there might be some hop-by-hop options which can be 1441 * returned to normal user. 1442 * See also RFC 2292 section 6 (or RFC 3542 section 8). 1443 */ 1444 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 1445 /* 1446 * Check if a hop-by-hop options header is contatined in the 1447 * received packet, and if so, store the options as ancillary 1448 * data. Note that a hop-by-hop options header must be 1449 * just after the IPv6 header, which is assured through the 1450 * IPv6 input processing. 1451 */ 1452 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1453 struct ip6_hbh *hbh; 1454 int hbhlen = 0; 1455#ifdef PULLDOWN_TEST 1456 struct mbuf *ext; 1457#endif 1458 1459#ifndef PULLDOWN_TEST 1460 hbh = (struct ip6_hbh *)(ip6 + 1); 1461 hbhlen = (hbh->ip6h_len + 1) << 3; 1462#else 1463 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1464 ip6->ip6_nxt); 1465 if (ext == NULL) { 1466 IP6STAT_INC(ip6s_tooshort); 1467 return; 1468 } 1469 hbh = mtod(ext, struct ip6_hbh *); 1470 hbhlen = (hbh->ip6h_len + 1) << 3; 1471 if (hbhlen != ext->m_len) { 1472 m_freem(ext); 1473 IP6STAT_INC(ip6s_tooshort); 1474 return; 1475 } 1476#endif 1477 1478 /* 1479 * XXX: We copy the whole header even if a 1480 * jumbo payload option is included, the option which 1481 * is to be removed before returning according to 1482 * RFC2292. 1483 * Note: this constraint is removed in RFC3542 1484 */ 1485 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1486 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS), 1487 IPPROTO_IPV6); 1488 if (*mp) 1489 mp = &(*mp)->m_next; 1490#ifdef PULLDOWN_TEST 1491 m_freem(ext); 1492#endif 1493 } 1494 } 1495 1496 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1497 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1498 1499 /* 1500 * Search for destination options headers or routing 1501 * header(s) through the header chain, and stores each 1502 * header as ancillary data. 1503 * Note that the order of the headers remains in 1504 * the chain of ancillary data. 1505 */ 1506 while (1) { /* is explicit loop prevention necessary? */ 1507 struct ip6_ext *ip6e = NULL; 1508 int elen; 1509#ifdef PULLDOWN_TEST 1510 struct mbuf *ext = NULL; 1511#endif 1512 1513 /* 1514 * if it is not an extension header, don't try to 1515 * pull it from the chain. 1516 */ 1517 switch (nxt) { 1518 case IPPROTO_DSTOPTS: 1519 case IPPROTO_ROUTING: 1520 case IPPROTO_HOPOPTS: 1521 case IPPROTO_AH: /* is it possible? */ 1522 break; 1523 default: 1524 goto loopend; 1525 } 1526 1527#ifndef PULLDOWN_TEST 1528 if (off + sizeof(*ip6e) > m->m_len) 1529 goto loopend; 1530 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1531 if (nxt == IPPROTO_AH) 1532 elen = (ip6e->ip6e_len + 2) << 2; 1533 else 1534 elen = (ip6e->ip6e_len + 1) << 3; 1535 if (off + elen > m->m_len) 1536 goto loopend; 1537#else 1538 ext = ip6_pullexthdr(m, off, nxt); 1539 if (ext == NULL) { 1540 IP6STAT_INC(ip6s_tooshort); 1541 return; 1542 } 1543 ip6e = mtod(ext, struct ip6_ext *); 1544 if (nxt == IPPROTO_AH) 1545 elen = (ip6e->ip6e_len + 2) << 2; 1546 else 1547 elen = (ip6e->ip6e_len + 1) << 3; 1548 if (elen != ext->m_len) { 1549 m_freem(ext); 1550 IP6STAT_INC(ip6s_tooshort); 1551 return; 1552 } 1553#endif 1554 1555 switch (nxt) { 1556 case IPPROTO_DSTOPTS: 1557 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1558 break; 1559 1560 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1561 IS2292(in6p, 1562 IPV6_2292DSTOPTS, IPV6_DSTOPTS), 1563 IPPROTO_IPV6); 1564 if (*mp) 1565 mp = &(*mp)->m_next; 1566 break; 1567 case IPPROTO_ROUTING: 1568 if (!(in6p->inp_flags & IN6P_RTHDR)) 1569 break; 1570 1571 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1572 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR), 1573 IPPROTO_IPV6); 1574 if (*mp) 1575 mp = &(*mp)->m_next; 1576 break; 1577 case IPPROTO_HOPOPTS: 1578 case IPPROTO_AH: /* is it possible? */ 1579 break; 1580 1581 default: 1582 /* 1583 * other cases have been filtered in the above. 1584 * none will visit this case. here we supply 1585 * the code just in case (nxt overwritten or 1586 * other cases). 1587 */ 1588#ifdef PULLDOWN_TEST 1589 m_freem(ext); 1590#endif 1591 goto loopend; 1592 1593 } 1594 1595 /* proceed with the next header. */ 1596 off += elen; 1597 nxt = ip6e->ip6e_nxt; 1598 ip6e = NULL; 1599#ifdef PULLDOWN_TEST 1600 m_freem(ext); 1601 ext = NULL; 1602#endif 1603 } 1604 loopend: 1605 ; 1606 } 1607} 1608#undef IS2292 1609 1610void 1611ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu) 1612{ 1613 struct socket *so; 1614 struct mbuf *m_mtu; 1615 struct ip6_mtuinfo mtuctl; 1616 1617 so = in6p->inp_socket; 1618 1619 if (mtu == NULL) 1620 return; 1621 1622#ifdef DIAGNOSTIC 1623 if (so == NULL) /* I believe this is impossible */ 1624 panic("ip6_notify_pmtu: socket is NULL"); 1625#endif 1626 1627 bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */ 1628 mtuctl.ip6m_mtu = *mtu; 1629 mtuctl.ip6m_addr = *dst; 1630 if (sa6_recoverscope(&mtuctl.ip6m_addr)) 1631 return; 1632 1633 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), 1634 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) 1635 return; 1636 1637 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu) 1638 == 0) { 1639 m_freem(m_mtu); 1640 /* XXX: should count statistics */ 1641 } else 1642 sorwakeup(so); 1643 1644 return; 1645} 1646 1647#ifdef PULLDOWN_TEST 1648/* 1649 * pull single extension header from mbuf chain. returns single mbuf that 1650 * contains the result, or NULL on error. 1651 */ 1652static struct mbuf * 1653ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1654{ 1655 struct ip6_ext ip6e; 1656 size_t elen; 1657 struct mbuf *n; 1658 1659#ifdef DIAGNOSTIC 1660 switch (nxt) { 1661 case IPPROTO_DSTOPTS: 1662 case IPPROTO_ROUTING: 1663 case IPPROTO_HOPOPTS: 1664 case IPPROTO_AH: /* is it possible? */ 1665 break; 1666 default: 1667 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1668 } 1669#endif 1670 1671 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1672 if (nxt == IPPROTO_AH) 1673 elen = (ip6e.ip6e_len + 2) << 2; 1674 else 1675 elen = (ip6e.ip6e_len + 1) << 3; 1676 1677 if (elen > MLEN) 1678 n = m_getcl(M_NOWAIT, MT_DATA, 0); 1679 else 1680 n = m_get(M_NOWAIT, MT_DATA); 1681 if (n == NULL) 1682 return NULL; 1683 1684 m_copydata(m, off, elen, mtod(n, caddr_t)); 1685 n->m_len = elen; 1686 return n; 1687} 1688#endif 1689 1690/* 1691 * Get pointer to the previous header followed by the header 1692 * currently processed. 1693 * XXX: This function supposes that 1694 * M includes all headers, 1695 * the next header field and the header length field of each header 1696 * are valid, and 1697 * the sum of each header length equals to OFF. 1698 * Because of these assumptions, this function must be called very 1699 * carefully. Moreover, it will not be used in the near future when 1700 * we develop `neater' mechanism to process extension headers. 1701 */ 1702char * 1703ip6_get_prevhdr(struct mbuf *m, int off) 1704{ 1705 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1706 1707 if (off == sizeof(struct ip6_hdr)) 1708 return (&ip6->ip6_nxt); 1709 else { 1710 int len, nxt; 1711 struct ip6_ext *ip6e = NULL; 1712 1713 nxt = ip6->ip6_nxt; 1714 len = sizeof(struct ip6_hdr); 1715 while (len < off) { 1716 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1717 1718 switch (nxt) { 1719 case IPPROTO_FRAGMENT: 1720 len += sizeof(struct ip6_frag); 1721 break; 1722 case IPPROTO_AH: 1723 len += (ip6e->ip6e_len + 2) << 2; 1724 break; 1725 default: 1726 len += (ip6e->ip6e_len + 1) << 3; 1727 break; 1728 } 1729 nxt = ip6e->ip6e_nxt; 1730 } 1731 if (ip6e) 1732 return (&ip6e->ip6e_nxt); 1733 else 1734 return NULL; 1735 } 1736} 1737 1738/* 1739 * get next header offset. m will be retained. 1740 */ 1741int 1742ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp) 1743{ 1744 struct ip6_hdr ip6; 1745 struct ip6_ext ip6e; 1746 struct ip6_frag fh; 1747 1748 /* just in case */ 1749 if (m == NULL) 1750 panic("ip6_nexthdr: m == NULL"); 1751 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1752 return -1; 1753 1754 switch (proto) { 1755 case IPPROTO_IPV6: 1756 if (m->m_pkthdr.len < off + sizeof(ip6)) 1757 return -1; 1758 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1759 if (nxtp) 1760 *nxtp = ip6.ip6_nxt; 1761 off += sizeof(ip6); 1762 return off; 1763 1764 case IPPROTO_FRAGMENT: 1765 /* 1766 * terminate parsing if it is not the first fragment, 1767 * it does not make sense to parse through it. 1768 */ 1769 if (m->m_pkthdr.len < off + sizeof(fh)) 1770 return -1; 1771 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1772 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ 1773 if (fh.ip6f_offlg & IP6F_OFF_MASK) 1774 return -1; 1775 if (nxtp) 1776 *nxtp = fh.ip6f_nxt; 1777 off += sizeof(struct ip6_frag); 1778 return off; 1779 1780 case IPPROTO_AH: 1781 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1782 return -1; 1783 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1784 if (nxtp) 1785 *nxtp = ip6e.ip6e_nxt; 1786 off += (ip6e.ip6e_len + 2) << 2; 1787 return off; 1788 1789 case IPPROTO_HOPOPTS: 1790 case IPPROTO_ROUTING: 1791 case IPPROTO_DSTOPTS: 1792 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1793 return -1; 1794 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1795 if (nxtp) 1796 *nxtp = ip6e.ip6e_nxt; 1797 off += (ip6e.ip6e_len + 1) << 3; 1798 return off; 1799 1800 case IPPROTO_NONE: 1801 case IPPROTO_ESP: 1802 case IPPROTO_IPCOMP: 1803 /* give up */ 1804 return -1; 1805 1806 default: 1807 return -1; 1808 } 1809 1810 return -1; 1811} 1812 1813/* 1814 * get offset for the last header in the chain. m will be kept untainted. 1815 */ 1816int 1817ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp) 1818{ 1819 int newoff; 1820 int nxt; 1821 1822 if (!nxtp) { 1823 nxt = -1; 1824 nxtp = &nxt; 1825 } 1826 while (1) { 1827 newoff = ip6_nexthdr(m, off, proto, nxtp); 1828 if (newoff < 0) 1829 return off; 1830 else if (newoff < off) 1831 return -1; /* invalid */ 1832 else if (newoff == off) 1833 return newoff; 1834 1835 off = newoff; 1836 proto = *nxtp; 1837 } 1838} 1839 1840static struct ip6aux * 1841ip6_addaux(struct mbuf *m) 1842{ 1843 struct m_tag *mtag; 1844 1845 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1846 if (!mtag) { 1847 mtag = m_tag_get(PACKET_TAG_IPV6_INPUT, sizeof(struct ip6aux), 1848 M_NOWAIT); 1849 if (mtag) { 1850 m_tag_prepend(m, mtag); 1851 bzero(mtag + 1, sizeof(struct ip6aux)); 1852 } 1853 } 1854 return mtag ? (struct ip6aux *)(mtag + 1) : NULL; 1855} 1856 1857static struct ip6aux * 1858ip6_findaux(struct mbuf *m) 1859{ 1860 struct m_tag *mtag; 1861 1862 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1863 return mtag ? (struct ip6aux *)(mtag + 1) : NULL; 1864} 1865 1866static void 1867ip6_delaux(struct mbuf *m) 1868{ 1869 struct m_tag *mtag; 1870 1871 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1872 if (mtag) 1873 m_tag_delete(m, mtag); 1874} 1875 1876/* 1877 * System control for IP6 1878 */ 1879 1880u_char inet6ctlerrmap[PRC_NCMDS] = { 1881 0, 0, 0, 0, 1882 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1883 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1884 EMSGSIZE, EHOSTUNREACH, 0, 0, 1885 0, 0, 0, 0, 1886 ENOPROTOOPT 1887}; 1888