ip6_input.c revision 262256
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 262256 2014-02-20 21:01:59Z ae $"); 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 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 575 IPV6_ADDR_MC_SCOPE(&ip6->ip6_dst) == 0) { 576 /* 577 * RFC4291 2.7: 578 * Nodes must not originate a packet to a multicast address 579 * whose scop field contains the reserved value 0; if such 580 * a packet is received, it must be silently dropped. 581 */ 582 IP6STAT_INC(ip6s_badscope); 583 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 584 goto bad; 585 } 586#ifdef ALTQ 587 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 588 /* packet is dropped by traffic conditioner */ 589 return; 590 } 591#endif 592 /* 593 * The following check is not documented in specs. A malicious 594 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 595 * and bypass security checks (act as if it was from 127.0.0.1 by using 596 * IPv6 src ::ffff:127.0.0.1). Be cautious. 597 * 598 * This check chokes if we are in an SIIT cloud. As none of BSDs 599 * support IPv4-less kernel compilation, we cannot support SIIT 600 * environment at all. So, it makes more sense for us to reject any 601 * malicious packets for non-SIIT environment, than try to do a 602 * partial support for SIIT environment. 603 */ 604 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 605 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 606 IP6STAT_INC(ip6s_badscope); 607 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 608 goto bad; 609 } 610#if 0 611 /* 612 * Reject packets with IPv4 compatible addresses (auto tunnel). 613 * 614 * The code forbids auto tunnel relay case in RFC1933 (the check is 615 * stronger than RFC1933). We may want to re-enable it if mech-xx 616 * is revised to forbid relaying case. 617 */ 618 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 619 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 620 IP6STAT_INC(ip6s_badscope); 621 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 622 goto bad; 623 } 624#endif 625#ifdef IPSEC 626 /* 627 * Bypass packet filtering for packets previously handled by IPsec. 628 */ 629 if (ip6_ipsec_filtertunnel(m)) 630 goto passin; 631#endif /* IPSEC */ 632 633 /* 634 * Run through list of hooks for input packets. 635 * 636 * NB: Beware of the destination address changing 637 * (e.g. by NAT rewriting). When this happens, 638 * tell ip6_forward to do the right thing. 639 */ 640 odst = ip6->ip6_dst; 641 642 /* Jump over all PFIL processing if hooks are not active. */ 643 if (!PFIL_HOOKED(&V_inet6_pfil_hook)) 644 goto passin; 645 646 if (pfil_run_hooks(&V_inet6_pfil_hook, &m, 647 m->m_pkthdr.rcvif, PFIL_IN, NULL)) 648 return; 649 if (m == NULL) /* consumed by filter */ 650 return; 651 ip6 = mtod(m, struct ip6_hdr *); 652 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 653 654 if (m->m_flags & M_FASTFWD_OURS) { 655 m->m_flags &= ~M_FASTFWD_OURS; 656 ours = 1; 657 deliverifp = m->m_pkthdr.rcvif; 658 goto hbhcheck; 659 } 660 if ((m->m_flags & M_IP6_NEXTHOP) && 661 m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) { 662 /* 663 * Directly ship the packet on. This allows forwarding 664 * packets originally destined to us to some other directly 665 * connected host. 666 */ 667 ip6_forward(m, 1); 668 goto out; 669 } 670 671passin: 672 /* 673 * Disambiguate address scope zones (if there is ambiguity). 674 * We first make sure that the original source or destination address 675 * is not in our internal form for scoped addresses. Such addresses 676 * are not necessarily invalid spec-wise, but we cannot accept them due 677 * to the usage conflict. 678 * in6_setscope() then also checks and rejects the cases where src or 679 * dst are the loopback address and the receiving interface 680 * is not loopback. 681 */ 682 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) { 683 IP6STAT_INC(ip6s_badscope); /* XXX */ 684 goto bad; 685 } 686 if (in6_setscope(&ip6->ip6_src, m->m_pkthdr.rcvif, NULL) || 687 in6_setscope(&ip6->ip6_dst, m->m_pkthdr.rcvif, NULL)) { 688 IP6STAT_INC(ip6s_badscope); 689 goto bad; 690 } 691 692 /* 693 * Multicast check. Assume packet is for us to avoid 694 * prematurely taking locks. 695 */ 696 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 697 ours = 1; 698 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 699 deliverifp = m->m_pkthdr.rcvif; 700 goto hbhcheck; 701 } 702 703 /* 704 * Unicast check 705 */ 706 707 bzero(&dst6, sizeof(dst6)); 708 dst6.sin6_family = AF_INET6; 709 dst6.sin6_len = sizeof(struct sockaddr_in6); 710 dst6.sin6_addr = ip6->ip6_dst; 711 ifp = m->m_pkthdr.rcvif; 712 IF_AFDATA_RLOCK(ifp); 713 lle = lla_lookup(LLTABLE6(ifp), 0, 714 (struct sockaddr *)&dst6); 715 IF_AFDATA_RUNLOCK(ifp); 716 if ((lle != NULL) && (lle->la_flags & LLE_IFADDR)) { 717 struct ifaddr *ifa; 718 struct in6_ifaddr *ia6; 719 int bad; 720 721 bad = 1; 722#define sa_equal(a1, a2) \ 723 (bcmp((a1), (a2), ((a1))->sin6_len) == 0) 724 IF_ADDR_RLOCK(ifp); 725 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 726 if (ifa->ifa_addr->sa_family != dst6.sin6_family) 727 continue; 728 if (sa_equal(&dst6, ifa->ifa_addr)) 729 break; 730 } 731 KASSERT(ifa != NULL, ("%s: ifa not found for lle %p", 732 __func__, lle)); 733#undef sa_equal 734 735 ia6 = (struct in6_ifaddr *)ifa; 736 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 737 /* Count the packet in the ip address stats */ 738 ia6->ia_ifa.if_ipackets++; 739 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len; 740 741 /* 742 * record address information into m_tag. 743 */ 744 (void)ip6_setdstifaddr(m, ia6); 745 746 bad = 0; 747 } else { 748 char ip6bufs[INET6_ADDRSTRLEN]; 749 char ip6bufd[INET6_ADDRSTRLEN]; 750 /* address is not ready, so discard the packet. */ 751 nd6log((LOG_INFO, 752 "ip6_input: packet to an unready address %s->%s\n", 753 ip6_sprintf(ip6bufs, &ip6->ip6_src), 754 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 755 } 756 IF_ADDR_RUNLOCK(ifp); 757 LLE_RUNLOCK(lle); 758 if (bad) 759 goto bad; 760 else { 761 ours = 1; 762 deliverifp = ifp; 763 goto hbhcheck; 764 } 765 } 766 if (lle != NULL) 767 LLE_RUNLOCK(lle); 768 769 dst = &rin6.ro_dst; 770 dst->sin6_len = sizeof(struct sockaddr_in6); 771 dst->sin6_family = AF_INET6; 772 dst->sin6_addr = ip6->ip6_dst; 773 rin6.ro_rt = in6_rtalloc1((struct sockaddr *)dst, 0, 0, M_GETFIB(m)); 774 if (rin6.ro_rt) 775 RT_UNLOCK(rin6.ro_rt); 776 777#define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 778 779 /* 780 * Accept the packet if the forwarding interface to the destination 781 * according to the routing table is the loopback interface, 782 * unless the associated route has a gateway. 783 * Note that this approach causes to accept a packet if there is a 784 * route to the loopback interface for the destination of the packet. 785 * But we think it's even useful in some situations, e.g. when using 786 * a special daemon which wants to intercept the packet. 787 * 788 * XXX: some OSes automatically make a cloned route for the destination 789 * of an outgoing packet. If the outgoing interface of the packet 790 * is a loopback one, the kernel would consider the packet to be 791 * accepted, even if we have no such address assinged on the interface. 792 * We check the cloned flag of the route entry to reject such cases, 793 * assuming that route entries for our own addresses are not made by 794 * cloning (it should be true because in6_addloop explicitly installs 795 * the host route). However, we might have to do an explicit check 796 * while it would be less efficient. Or, should we rather install a 797 * reject route for such a case? 798 */ 799 if (rin6.ro_rt && 800 (rin6.ro_rt->rt_flags & 801 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 802#ifdef RTF_WASCLONED 803 !(rin6.ro_rt->rt_flags & RTF_WASCLONED) && 804#endif 805#ifdef RTF_CLONED 806 !(rin6.ro_rt->rt_flags & RTF_CLONED) && 807#endif 808#if 0 809 /* 810 * The check below is redundant since the comparison of 811 * the destination and the key of the rtentry has 812 * already done through looking up the routing table. 813 */ 814 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 815 &rt6_key(rin6.ro_rt)->sin6_addr) 816#endif 817 rin6.ro_rt->rt_ifp->if_type == IFT_LOOP) { 818 int free_ia6 = 0; 819 struct in6_ifaddr *ia6; 820 821 /* 822 * found the loopback route to the interface address 823 */ 824 if (rin6.ro_rt->rt_gateway->sa_family == AF_LINK) { 825 struct sockaddr_in6 dest6; 826 827 bzero(&dest6, sizeof(dest6)); 828 dest6.sin6_family = AF_INET6; 829 dest6.sin6_len = sizeof(dest6); 830 dest6.sin6_addr = ip6->ip6_dst; 831 ia6 = (struct in6_ifaddr *) 832 ifa_ifwithaddr((struct sockaddr *)&dest6); 833 if (ia6 == NULL) 834 goto bad; 835 free_ia6 = 1; 836 } 837 else 838 ia6 = (struct in6_ifaddr *)rin6.ro_rt->rt_ifa; 839 840 /* 841 * record address information into m_tag. 842 */ 843 (void)ip6_setdstifaddr(m, ia6); 844 845 /* 846 * packets to a tentative, duplicated, or somehow invalid 847 * address must not be accepted. 848 */ 849 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 850 /* this address is ready */ 851 ours = 1; 852 deliverifp = ia6->ia_ifp; /* correct? */ 853 /* Count the packet in the ip address stats */ 854 ia6->ia_ifa.if_ipackets++; 855 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len; 856 if (ia6 != NULL && free_ia6 != 0) 857 ifa_free(&ia6->ia_ifa); 858 goto hbhcheck; 859 } else { 860 char ip6bufs[INET6_ADDRSTRLEN]; 861 char ip6bufd[INET6_ADDRSTRLEN]; 862 /* address is not ready, so discard the packet. */ 863 nd6log((LOG_INFO, 864 "ip6_input: packet to an unready address %s->%s\n", 865 ip6_sprintf(ip6bufs, &ip6->ip6_src), 866 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 867 868 if (ia6 != NULL && free_ia6 != 0) 869 ifa_free(&ia6->ia_ifa); 870 goto bad; 871 } 872 } 873 874 /* 875 * FAITH (Firewall Aided Internet Translator) 876 */ 877 if (V_ip6_keepfaith) { 878 if (rin6.ro_rt && rin6.ro_rt->rt_ifp && 879 rin6.ro_rt->rt_ifp->if_type == IFT_FAITH) { 880 /* XXX do we need more sanity checks? */ 881 ours = 1; 882 deliverifp = rin6.ro_rt->rt_ifp; /* faith */ 883 goto hbhcheck; 884 } 885 } 886 887 /* 888 * Now there is no reason to process the packet if it's not our own 889 * and we're not a router. 890 */ 891 if (!V_ip6_forwarding) { 892 IP6STAT_INC(ip6s_cantforward); 893 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 894 goto bad; 895 } 896 897 hbhcheck: 898 /* 899 * record address information into m_tag, if we don't have one yet. 900 * note that we are unable to record it, if the address is not listed 901 * as our interface address (e.g. multicast addresses, addresses 902 * within FAITH prefixes and such). 903 */ 904 if (deliverifp) { 905 struct in6_ifaddr *ia6; 906 907 if ((ia6 = ip6_getdstifaddr(m)) != NULL) { 908 ifa_free(&ia6->ia_ifa); 909 } else { 910 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 911 if (ia6) { 912 if (!ip6_setdstifaddr(m, ia6)) { 913 /* 914 * XXX maybe we should drop the packet here, 915 * as we could not provide enough information 916 * to the upper layers. 917 */ 918 } 919 ifa_free(&ia6->ia_ifa); 920 } 921 } 922 } 923 924 /* 925 * Process Hop-by-Hop options header if it's contained. 926 * m may be modified in ip6_hopopts_input(). 927 * If a JumboPayload option is included, plen will also be modified. 928 */ 929 plen = (u_int32_t)ntohs(ip6->ip6_plen); 930 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 931 int error; 932 933 error = ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours); 934 if (error != 0) 935 goto out; 936 } else 937 nxt = ip6->ip6_nxt; 938 939 /* 940 * Check that the amount of data in the buffers 941 * is as at least much as the IPv6 header would have us expect. 942 * Trim mbufs if longer than we expect. 943 * Drop packet if shorter than we expect. 944 */ 945 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 946 IP6STAT_INC(ip6s_tooshort); 947 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 948 goto bad; 949 } 950 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 951 if (m->m_len == m->m_pkthdr.len) { 952 m->m_len = sizeof(struct ip6_hdr) + plen; 953 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 954 } else 955 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 956 } 957 958 /* 959 * Forward if desirable. 960 */ 961 if (V_ip6_mrouter && 962 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 963 /* 964 * If we are acting as a multicast router, all 965 * incoming multicast packets are passed to the 966 * kernel-level multicast forwarding function. 967 * The packet is returned (relatively) intact; if 968 * ip6_mforward() returns a non-zero value, the packet 969 * must be discarded, else it may be accepted below. 970 * 971 * XXX TODO: Check hlim and multicast scope here to avoid 972 * unnecessarily calling into ip6_mforward(). 973 */ 974 if (ip6_mforward && 975 ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 976 IP6STAT_INC(ip6s_cantforward); 977 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 978 goto bad; 979 } 980 } else if (!ours) { 981 ip6_forward(m, srcrt); 982 goto out; 983 } 984 985 ip6 = mtod(m, struct ip6_hdr *); 986 987 /* 988 * Malicious party may be able to use IPv4 mapped addr to confuse 989 * tcp/udp stack and bypass security checks (act as if it was from 990 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 991 * 992 * For SIIT end node behavior, you may want to disable the check. 993 * However, you will become vulnerable to attacks using IPv4 mapped 994 * source. 995 */ 996 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 997 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 998 IP6STAT_INC(ip6s_badscope); 999 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 1000 goto bad; 1001 } 1002 1003 /* 1004 * Tell launch routine the next header 1005 */ 1006 IP6STAT_INC(ip6s_delivered); 1007 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 1008 nest = 0; 1009 1010 while (nxt != IPPROTO_DONE) { 1011 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 1012 IP6STAT_INC(ip6s_toomanyhdr); 1013 goto bad; 1014 } 1015 1016 /* 1017 * protection against faulty packet - there should be 1018 * more sanity checks in header chain processing. 1019 */ 1020 if (m->m_pkthdr.len < off) { 1021 IP6STAT_INC(ip6s_tooshort); 1022 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 1023 goto bad; 1024 } 1025 1026#ifdef IPSEC 1027 /* 1028 * enforce IPsec policy checking if we are seeing last header. 1029 * note that we do not visit this with protocols with pcb layer 1030 * code - like udp/tcp/raw ip. 1031 */ 1032 if (ip6_ipsec_input(m, nxt)) 1033 goto bad; 1034#endif /* IPSEC */ 1035 1036 /* 1037 * Use mbuf flags to propagate Router Alert option to 1038 * ICMPv6 layer, as hop-by-hop options have been stripped. 1039 */ 1040 if (nxt == IPPROTO_ICMPV6 && rtalert != ~0) 1041 m->m_flags |= M_RTALERT_MLD; 1042 1043 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 1044 } 1045 goto out; 1046bad: 1047 m_freem(m); 1048out: 1049 if (rin6.ro_rt) 1050 RTFREE(rin6.ro_rt); 1051} 1052 1053/* 1054 * set/grab in6_ifaddr correspond to IPv6 destination address. 1055 * XXX backward compatibility wrapper 1056 * 1057 * XXXRW: We should bump the refcount on ia6 before sticking it in the m_tag, 1058 * and then bump it when the tag is copied, and release it when the tag is 1059 * freed. Unfortunately, m_tags don't support deep copies (yet), so instead 1060 * we just bump the ia refcount when we receive it. This should be fixed. 1061 */ 1062static struct ip6aux * 1063ip6_setdstifaddr(struct mbuf *m, struct in6_ifaddr *ia6) 1064{ 1065 struct ip6aux *ip6a; 1066 1067 ip6a = ip6_addaux(m); 1068 if (ip6a) 1069 ip6a->ip6a_dstia6 = ia6; 1070 return ip6a; /* NULL if failed to set */ 1071} 1072 1073struct in6_ifaddr * 1074ip6_getdstifaddr(struct mbuf *m) 1075{ 1076 struct ip6aux *ip6a; 1077 struct in6_ifaddr *ia; 1078 1079 ip6a = ip6_findaux(m); 1080 if (ip6a) { 1081 ia = ip6a->ip6a_dstia6; 1082 ifa_ref(&ia->ia_ifa); 1083 return ia; 1084 } else 1085 return NULL; 1086} 1087 1088/* 1089 * Hop-by-Hop options header processing. If a valid jumbo payload option is 1090 * included, the real payload length will be stored in plenp. 1091 * 1092 * rtalertp - XXX: should be stored more smart way 1093 */ 1094static int 1095ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp, 1096 struct mbuf **mp, int *offp) 1097{ 1098 struct mbuf *m = *mp; 1099 int off = *offp, hbhlen; 1100 struct ip6_hbh *hbh; 1101 u_int8_t *opt; 1102 1103 /* validation of the length of the header */ 1104#ifndef PULLDOWN_TEST 1105 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 1106 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 1107 hbhlen = (hbh->ip6h_len + 1) << 3; 1108 1109 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 1110 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 1111#else 1112 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1113 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1114 if (hbh == NULL) { 1115 IP6STAT_INC(ip6s_tooshort); 1116 return -1; 1117 } 1118 hbhlen = (hbh->ip6h_len + 1) << 3; 1119 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 1120 hbhlen); 1121 if (hbh == NULL) { 1122 IP6STAT_INC(ip6s_tooshort); 1123 return -1; 1124 } 1125#endif 1126 off += hbhlen; 1127 hbhlen -= sizeof(struct ip6_hbh); 1128 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 1129 1130 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 1131 hbhlen, rtalertp, plenp) < 0) 1132 return (-1); 1133 1134 *offp = off; 1135 *mp = m; 1136 return (0); 1137} 1138 1139/* 1140 * Search header for all Hop-by-hop options and process each option. 1141 * This function is separate from ip6_hopopts_input() in order to 1142 * handle a case where the sending node itself process its hop-by-hop 1143 * options header. In such a case, the function is called from ip6_output(). 1144 * 1145 * The function assumes that hbh header is located right after the IPv6 header 1146 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 1147 * opthead + hbhlen is located in contiguous memory region. 1148 */ 1149int 1150ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 1151 u_int32_t *rtalertp, u_int32_t *plenp) 1152{ 1153 struct ip6_hdr *ip6; 1154 int optlen = 0; 1155 u_int8_t *opt = opthead; 1156 u_int16_t rtalert_val; 1157 u_int32_t jumboplen; 1158 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 1159 1160 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 1161 switch (*opt) { 1162 case IP6OPT_PAD1: 1163 optlen = 1; 1164 break; 1165 case IP6OPT_PADN: 1166 if (hbhlen < IP6OPT_MINLEN) { 1167 IP6STAT_INC(ip6s_toosmall); 1168 goto bad; 1169 } 1170 optlen = *(opt + 1) + 2; 1171 break; 1172 case IP6OPT_ROUTER_ALERT: 1173 /* XXX may need check for alignment */ 1174 if (hbhlen < IP6OPT_RTALERT_LEN) { 1175 IP6STAT_INC(ip6s_toosmall); 1176 goto bad; 1177 } 1178 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 1179 /* XXX stat */ 1180 icmp6_error(m, ICMP6_PARAM_PROB, 1181 ICMP6_PARAMPROB_HEADER, 1182 erroff + opt + 1 - opthead); 1183 return (-1); 1184 } 1185 optlen = IP6OPT_RTALERT_LEN; 1186 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 1187 *rtalertp = ntohs(rtalert_val); 1188 break; 1189 case IP6OPT_JUMBO: 1190 /* XXX may need check for alignment */ 1191 if (hbhlen < IP6OPT_JUMBO_LEN) { 1192 IP6STAT_INC(ip6s_toosmall); 1193 goto bad; 1194 } 1195 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 1196 /* XXX stat */ 1197 icmp6_error(m, ICMP6_PARAM_PROB, 1198 ICMP6_PARAMPROB_HEADER, 1199 erroff + opt + 1 - opthead); 1200 return (-1); 1201 } 1202 optlen = IP6OPT_JUMBO_LEN; 1203 1204 /* 1205 * IPv6 packets that have non 0 payload length 1206 * must not contain a jumbo payload option. 1207 */ 1208 ip6 = mtod(m, struct ip6_hdr *); 1209 if (ip6->ip6_plen) { 1210 IP6STAT_INC(ip6s_badoptions); 1211 icmp6_error(m, ICMP6_PARAM_PROB, 1212 ICMP6_PARAMPROB_HEADER, 1213 erroff + opt - opthead); 1214 return (-1); 1215 } 1216 1217 /* 1218 * We may see jumbolen in unaligned location, so 1219 * we'd need to perform bcopy(). 1220 */ 1221 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 1222 jumboplen = (u_int32_t)htonl(jumboplen); 1223 1224#if 1 1225 /* 1226 * if there are multiple jumbo payload options, 1227 * *plenp will be non-zero and the packet will be 1228 * rejected. 1229 * the behavior may need some debate in ipngwg - 1230 * multiple options does not make sense, however, 1231 * there's no explicit mention in specification. 1232 */ 1233 if (*plenp != 0) { 1234 IP6STAT_INC(ip6s_badoptions); 1235 icmp6_error(m, ICMP6_PARAM_PROB, 1236 ICMP6_PARAMPROB_HEADER, 1237 erroff + opt + 2 - opthead); 1238 return (-1); 1239 } 1240#endif 1241 1242 /* 1243 * jumbo payload length must be larger than 65535. 1244 */ 1245 if (jumboplen <= IPV6_MAXPACKET) { 1246 IP6STAT_INC(ip6s_badoptions); 1247 icmp6_error(m, ICMP6_PARAM_PROB, 1248 ICMP6_PARAMPROB_HEADER, 1249 erroff + opt + 2 - opthead); 1250 return (-1); 1251 } 1252 *plenp = jumboplen; 1253 1254 break; 1255 default: /* unknown option */ 1256 if (hbhlen < IP6OPT_MINLEN) { 1257 IP6STAT_INC(ip6s_toosmall); 1258 goto bad; 1259 } 1260 optlen = ip6_unknown_opt(opt, m, 1261 erroff + opt - opthead); 1262 if (optlen == -1) 1263 return (-1); 1264 optlen += 2; 1265 break; 1266 } 1267 } 1268 1269 return (0); 1270 1271 bad: 1272 m_freem(m); 1273 return (-1); 1274} 1275 1276/* 1277 * Unknown option processing. 1278 * The third argument `off' is the offset from the IPv6 header to the option, 1279 * which is necessary if the IPv6 header the and option header and IPv6 header 1280 * is not contiguous in order to return an ICMPv6 error. 1281 */ 1282int 1283ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 1284{ 1285 struct ip6_hdr *ip6; 1286 1287 switch (IP6OPT_TYPE(*optp)) { 1288 case IP6OPT_TYPE_SKIP: /* ignore the option */ 1289 return ((int)*(optp + 1)); 1290 case IP6OPT_TYPE_DISCARD: /* silently discard */ 1291 m_freem(m); 1292 return (-1); 1293 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 1294 IP6STAT_INC(ip6s_badoptions); 1295 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 1296 return (-1); 1297 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 1298 IP6STAT_INC(ip6s_badoptions); 1299 ip6 = mtod(m, struct ip6_hdr *); 1300 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 1301 (m->m_flags & (M_BCAST|M_MCAST))) 1302 m_freem(m); 1303 else 1304 icmp6_error(m, ICMP6_PARAM_PROB, 1305 ICMP6_PARAMPROB_OPTION, off); 1306 return (-1); 1307 } 1308 1309 m_freem(m); /* XXX: NOTREACHED */ 1310 return (-1); 1311} 1312 1313/* 1314 * Create the "control" list for this pcb. 1315 * These functions will not modify mbuf chain at all. 1316 * 1317 * With KAME mbuf chain restriction: 1318 * The routine will be called from upper layer handlers like tcp6_input(). 1319 * Thus the routine assumes that the caller (tcp6_input) have already 1320 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1321 * very first mbuf on the mbuf chain. 1322 * 1323 * ip6_savecontrol_v4 will handle those options that are possible to be 1324 * set on a v4-mapped socket. 1325 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those 1326 * options and handle the v6-only ones itself. 1327 */ 1328struct mbuf ** 1329ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp, 1330 int *v4only) 1331{ 1332 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1333 1334#ifdef SO_TIMESTAMP 1335 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) { 1336 struct timeval tv; 1337 1338 microtime(&tv); 1339 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1340 SCM_TIMESTAMP, SOL_SOCKET); 1341 if (*mp) 1342 mp = &(*mp)->m_next; 1343 } 1344#endif 1345 1346#define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y)) 1347 /* RFC 2292 sec. 5 */ 1348 if ((inp->inp_flags & IN6P_PKTINFO) != 0) { 1349 struct in6_pktinfo pi6; 1350 1351 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1352#ifdef INET 1353 struct ip *ip; 1354 1355 ip = mtod(m, struct ip *); 1356 pi6.ipi6_addr.s6_addr32[0] = 0; 1357 pi6.ipi6_addr.s6_addr32[1] = 0; 1358 pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP; 1359 pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr; 1360#else 1361 /* We won't hit this code */ 1362 bzero(&pi6.ipi6_addr, sizeof(struct in6_addr)); 1363#endif 1364 } else { 1365 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1366 in6_clearscope(&pi6.ipi6_addr); /* XXX */ 1367 } 1368 pi6.ipi6_ifindex = 1369 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0; 1370 1371 *mp = sbcreatecontrol((caddr_t) &pi6, 1372 sizeof(struct in6_pktinfo), 1373 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6); 1374 if (*mp) 1375 mp = &(*mp)->m_next; 1376 } 1377 1378 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) { 1379 int hlim; 1380 1381 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1382#ifdef INET 1383 struct ip *ip; 1384 1385 ip = mtod(m, struct ip *); 1386 hlim = ip->ip_ttl; 1387#else 1388 /* We won't hit this code */ 1389 hlim = 0; 1390#endif 1391 } else { 1392 hlim = ip6->ip6_hlim & 0xff; 1393 } 1394 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 1395 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), 1396 IPPROTO_IPV6); 1397 if (*mp) 1398 mp = &(*mp)->m_next; 1399 } 1400 1401 if ((inp->inp_flags & IN6P_TCLASS) != 0) { 1402 int tclass; 1403 1404 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1405#ifdef INET 1406 struct ip *ip; 1407 1408 ip = mtod(m, struct ip *); 1409 tclass = ip->ip_tos; 1410#else 1411 /* We won't hit this code */ 1412 tclass = 0; 1413#endif 1414 } else { 1415 u_int32_t flowinfo; 1416 1417 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1418 flowinfo >>= 20; 1419 tclass = flowinfo & 0xff; 1420 } 1421 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int), 1422 IPV6_TCLASS, IPPROTO_IPV6); 1423 if (*mp) 1424 mp = &(*mp)->m_next; 1425 } 1426 1427 if (v4only != NULL) { 1428 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1429 *v4only = 1; 1430 } else { 1431 *v4only = 0; 1432 } 1433 } 1434 1435 return (mp); 1436} 1437 1438void 1439ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 1440{ 1441 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1442 int v4only = 0; 1443 1444 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only); 1445 if (v4only) 1446 return; 1447 1448 /* 1449 * IPV6_HOPOPTS socket option. Recall that we required super-user 1450 * privilege for the option (see ip6_ctloutput), but it might be too 1451 * strict, since there might be some hop-by-hop options which can be 1452 * returned to normal user. 1453 * See also RFC 2292 section 6 (or RFC 3542 section 8). 1454 */ 1455 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 1456 /* 1457 * Check if a hop-by-hop options header is contatined in the 1458 * received packet, and if so, store the options as ancillary 1459 * data. Note that a hop-by-hop options header must be 1460 * just after the IPv6 header, which is assured through the 1461 * IPv6 input processing. 1462 */ 1463 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1464 struct ip6_hbh *hbh; 1465 int hbhlen = 0; 1466#ifdef PULLDOWN_TEST 1467 struct mbuf *ext; 1468#endif 1469 1470#ifndef PULLDOWN_TEST 1471 hbh = (struct ip6_hbh *)(ip6 + 1); 1472 hbhlen = (hbh->ip6h_len + 1) << 3; 1473#else 1474 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1475 ip6->ip6_nxt); 1476 if (ext == NULL) { 1477 IP6STAT_INC(ip6s_tooshort); 1478 return; 1479 } 1480 hbh = mtod(ext, struct ip6_hbh *); 1481 hbhlen = (hbh->ip6h_len + 1) << 3; 1482 if (hbhlen != ext->m_len) { 1483 m_freem(ext); 1484 IP6STAT_INC(ip6s_tooshort); 1485 return; 1486 } 1487#endif 1488 1489 /* 1490 * XXX: We copy the whole header even if a 1491 * jumbo payload option is included, the option which 1492 * is to be removed before returning according to 1493 * RFC2292. 1494 * Note: this constraint is removed in RFC3542 1495 */ 1496 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1497 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS), 1498 IPPROTO_IPV6); 1499 if (*mp) 1500 mp = &(*mp)->m_next; 1501#ifdef PULLDOWN_TEST 1502 m_freem(ext); 1503#endif 1504 } 1505 } 1506 1507 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1508 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1509 1510 /* 1511 * Search for destination options headers or routing 1512 * header(s) through the header chain, and stores each 1513 * header as ancillary data. 1514 * Note that the order of the headers remains in 1515 * the chain of ancillary data. 1516 */ 1517 while (1) { /* is explicit loop prevention necessary? */ 1518 struct ip6_ext *ip6e = NULL; 1519 int elen; 1520#ifdef PULLDOWN_TEST 1521 struct mbuf *ext = NULL; 1522#endif 1523 1524 /* 1525 * if it is not an extension header, don't try to 1526 * pull it from the chain. 1527 */ 1528 switch (nxt) { 1529 case IPPROTO_DSTOPTS: 1530 case IPPROTO_ROUTING: 1531 case IPPROTO_HOPOPTS: 1532 case IPPROTO_AH: /* is it possible? */ 1533 break; 1534 default: 1535 goto loopend; 1536 } 1537 1538#ifndef PULLDOWN_TEST 1539 if (off + sizeof(*ip6e) > m->m_len) 1540 goto loopend; 1541 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1542 if (nxt == IPPROTO_AH) 1543 elen = (ip6e->ip6e_len + 2) << 2; 1544 else 1545 elen = (ip6e->ip6e_len + 1) << 3; 1546 if (off + elen > m->m_len) 1547 goto loopend; 1548#else 1549 ext = ip6_pullexthdr(m, off, nxt); 1550 if (ext == NULL) { 1551 IP6STAT_INC(ip6s_tooshort); 1552 return; 1553 } 1554 ip6e = mtod(ext, struct ip6_ext *); 1555 if (nxt == IPPROTO_AH) 1556 elen = (ip6e->ip6e_len + 2) << 2; 1557 else 1558 elen = (ip6e->ip6e_len + 1) << 3; 1559 if (elen != ext->m_len) { 1560 m_freem(ext); 1561 IP6STAT_INC(ip6s_tooshort); 1562 return; 1563 } 1564#endif 1565 1566 switch (nxt) { 1567 case IPPROTO_DSTOPTS: 1568 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1569 break; 1570 1571 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1572 IS2292(in6p, 1573 IPV6_2292DSTOPTS, IPV6_DSTOPTS), 1574 IPPROTO_IPV6); 1575 if (*mp) 1576 mp = &(*mp)->m_next; 1577 break; 1578 case IPPROTO_ROUTING: 1579 if (!(in6p->inp_flags & IN6P_RTHDR)) 1580 break; 1581 1582 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1583 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR), 1584 IPPROTO_IPV6); 1585 if (*mp) 1586 mp = &(*mp)->m_next; 1587 break; 1588 case IPPROTO_HOPOPTS: 1589 case IPPROTO_AH: /* is it possible? */ 1590 break; 1591 1592 default: 1593 /* 1594 * other cases have been filtered in the above. 1595 * none will visit this case. here we supply 1596 * the code just in case (nxt overwritten or 1597 * other cases). 1598 */ 1599#ifdef PULLDOWN_TEST 1600 m_freem(ext); 1601#endif 1602 goto loopend; 1603 1604 } 1605 1606 /* proceed with the next header. */ 1607 off += elen; 1608 nxt = ip6e->ip6e_nxt; 1609 ip6e = NULL; 1610#ifdef PULLDOWN_TEST 1611 m_freem(ext); 1612 ext = NULL; 1613#endif 1614 } 1615 loopend: 1616 ; 1617 } 1618} 1619#undef IS2292 1620 1621void 1622ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu) 1623{ 1624 struct socket *so; 1625 struct mbuf *m_mtu; 1626 struct ip6_mtuinfo mtuctl; 1627 1628 so = in6p->inp_socket; 1629 1630 if (mtu == NULL) 1631 return; 1632 1633#ifdef DIAGNOSTIC 1634 if (so == NULL) /* I believe this is impossible */ 1635 panic("ip6_notify_pmtu: socket is NULL"); 1636#endif 1637 1638 bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */ 1639 mtuctl.ip6m_mtu = *mtu; 1640 mtuctl.ip6m_addr = *dst; 1641 if (sa6_recoverscope(&mtuctl.ip6m_addr)) 1642 return; 1643 1644 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), 1645 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) 1646 return; 1647 1648 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu) 1649 == 0) { 1650 m_freem(m_mtu); 1651 /* XXX: should count statistics */ 1652 } else 1653 sorwakeup(so); 1654 1655 return; 1656} 1657 1658#ifdef PULLDOWN_TEST 1659/* 1660 * pull single extension header from mbuf chain. returns single mbuf that 1661 * contains the result, or NULL on error. 1662 */ 1663static struct mbuf * 1664ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1665{ 1666 struct ip6_ext ip6e; 1667 size_t elen; 1668 struct mbuf *n; 1669 1670#ifdef DIAGNOSTIC 1671 switch (nxt) { 1672 case IPPROTO_DSTOPTS: 1673 case IPPROTO_ROUTING: 1674 case IPPROTO_HOPOPTS: 1675 case IPPROTO_AH: /* is it possible? */ 1676 break; 1677 default: 1678 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1679 } 1680#endif 1681 1682 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1683 if (nxt == IPPROTO_AH) 1684 elen = (ip6e.ip6e_len + 2) << 2; 1685 else 1686 elen = (ip6e.ip6e_len + 1) << 3; 1687 1688 if (elen > MLEN) 1689 n = m_getcl(M_NOWAIT, MT_DATA, 0); 1690 else 1691 n = m_get(M_NOWAIT, MT_DATA); 1692 if (n == NULL) 1693 return NULL; 1694 1695 m_copydata(m, off, elen, mtod(n, caddr_t)); 1696 n->m_len = elen; 1697 return n; 1698} 1699#endif 1700 1701/* 1702 * Get pointer to the previous header followed by the header 1703 * currently processed. 1704 * XXX: This function supposes that 1705 * M includes all headers, 1706 * the next header field and the header length field of each header 1707 * are valid, and 1708 * the sum of each header length equals to OFF. 1709 * Because of these assumptions, this function must be called very 1710 * carefully. Moreover, it will not be used in the near future when 1711 * we develop `neater' mechanism to process extension headers. 1712 */ 1713char * 1714ip6_get_prevhdr(struct mbuf *m, int off) 1715{ 1716 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1717 1718 if (off == sizeof(struct ip6_hdr)) 1719 return (&ip6->ip6_nxt); 1720 else { 1721 int len, nxt; 1722 struct ip6_ext *ip6e = NULL; 1723 1724 nxt = ip6->ip6_nxt; 1725 len = sizeof(struct ip6_hdr); 1726 while (len < off) { 1727 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1728 1729 switch (nxt) { 1730 case IPPROTO_FRAGMENT: 1731 len += sizeof(struct ip6_frag); 1732 break; 1733 case IPPROTO_AH: 1734 len += (ip6e->ip6e_len + 2) << 2; 1735 break; 1736 default: 1737 len += (ip6e->ip6e_len + 1) << 3; 1738 break; 1739 } 1740 nxt = ip6e->ip6e_nxt; 1741 } 1742 if (ip6e) 1743 return (&ip6e->ip6e_nxt); 1744 else 1745 return NULL; 1746 } 1747} 1748 1749/* 1750 * get next header offset. m will be retained. 1751 */ 1752int 1753ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp) 1754{ 1755 struct ip6_hdr ip6; 1756 struct ip6_ext ip6e; 1757 struct ip6_frag fh; 1758 1759 /* just in case */ 1760 if (m == NULL) 1761 panic("ip6_nexthdr: m == NULL"); 1762 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1763 return -1; 1764 1765 switch (proto) { 1766 case IPPROTO_IPV6: 1767 if (m->m_pkthdr.len < off + sizeof(ip6)) 1768 return -1; 1769 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1770 if (nxtp) 1771 *nxtp = ip6.ip6_nxt; 1772 off += sizeof(ip6); 1773 return off; 1774 1775 case IPPROTO_FRAGMENT: 1776 /* 1777 * terminate parsing if it is not the first fragment, 1778 * it does not make sense to parse through it. 1779 */ 1780 if (m->m_pkthdr.len < off + sizeof(fh)) 1781 return -1; 1782 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1783 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ 1784 if (fh.ip6f_offlg & IP6F_OFF_MASK) 1785 return -1; 1786 if (nxtp) 1787 *nxtp = fh.ip6f_nxt; 1788 off += sizeof(struct ip6_frag); 1789 return off; 1790 1791 case IPPROTO_AH: 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 + 2) << 2; 1798 return off; 1799 1800 case IPPROTO_HOPOPTS: 1801 case IPPROTO_ROUTING: 1802 case IPPROTO_DSTOPTS: 1803 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1804 return -1; 1805 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1806 if (nxtp) 1807 *nxtp = ip6e.ip6e_nxt; 1808 off += (ip6e.ip6e_len + 1) << 3; 1809 return off; 1810 1811 case IPPROTO_NONE: 1812 case IPPROTO_ESP: 1813 case IPPROTO_IPCOMP: 1814 /* give up */ 1815 return -1; 1816 1817 default: 1818 return -1; 1819 } 1820 1821 return -1; 1822} 1823 1824/* 1825 * get offset for the last header in the chain. m will be kept untainted. 1826 */ 1827int 1828ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp) 1829{ 1830 int newoff; 1831 int nxt; 1832 1833 if (!nxtp) { 1834 nxt = -1; 1835 nxtp = &nxt; 1836 } 1837 while (1) { 1838 newoff = ip6_nexthdr(m, off, proto, nxtp); 1839 if (newoff < 0) 1840 return off; 1841 else if (newoff < off) 1842 return -1; /* invalid */ 1843 else if (newoff == off) 1844 return newoff; 1845 1846 off = newoff; 1847 proto = *nxtp; 1848 } 1849} 1850 1851static struct ip6aux * 1852ip6_addaux(struct mbuf *m) 1853{ 1854 struct m_tag *mtag; 1855 1856 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1857 if (!mtag) { 1858 mtag = m_tag_get(PACKET_TAG_IPV6_INPUT, sizeof(struct ip6aux), 1859 M_NOWAIT); 1860 if (mtag) { 1861 m_tag_prepend(m, mtag); 1862 bzero(mtag + 1, sizeof(struct ip6aux)); 1863 } 1864 } 1865 return mtag ? (struct ip6aux *)(mtag + 1) : NULL; 1866} 1867 1868static struct ip6aux * 1869ip6_findaux(struct mbuf *m) 1870{ 1871 struct m_tag *mtag; 1872 1873 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1874 return mtag ? (struct ip6aux *)(mtag + 1) : NULL; 1875} 1876 1877static void 1878ip6_delaux(struct mbuf *m) 1879{ 1880 struct m_tag *mtag; 1881 1882 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1883 if (mtag) 1884 m_tag_delete(m, mtag); 1885} 1886 1887/* 1888 * System control for IP6 1889 */ 1890 1891u_char inet6ctlerrmap[PRC_NCMDS] = { 1892 0, 0, 0, 0, 1893 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1894 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1895 EMSGSIZE, EHOSTUNREACH, 0, 0, 1896 0, 0, 0, 0, 1897 ENOPROTOOPT 1898}; 1899