1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $ 32 */ 33 34 /*- 35 * Copyright (c) 1982, 1986, 1988, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. Neither the name of the University nor the names of its contributors 47 * may be used to endorse or promote products derived from this software 48 * without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 * 62 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 63 */ 64 65 #include <sys/cdefs.h> 66 __FBSDID("$FreeBSD$"); 67 68 #include "opt_inet.h" 69 #include "opt_inet6.h" 70 #include "opt_ipsec.h" 71 #include "opt_route.h" 72 #include "opt_rss.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/hhook.h> 77 #include <sys/malloc.h> 78 #include <sys/mbuf.h> 79 #include <sys/proc.h> 80 #include <sys/domain.h> 81 #include <sys/protosw.h> 82 #include <sys/sdt.h> 83 #include <sys/socket.h> 84 #include <sys/socketvar.h> 85 #include <sys/errno.h> 86 #include <sys/time.h> 87 #include <sys/kernel.h> 88 #include <sys/lock.h> 89 #include <sys/rmlock.h> 90 #include <sys/syslog.h> 91 #include <sys/sysctl.h> 92 93 #include <net/if.h> 94 #include <net/if_var.h> 95 #include <net/if_types.h> 96 #include <net/if_dl.h> 97 #include <net/route.h> 98 #include <net/netisr.h> 99 #include <net/rss_config.h> 100 #include <net/pfil.h> 101 #include <net/vnet.h> 102 103 #include <netinet/in.h> 104 #include <netinet/in_kdtrace.h> 105 #include <netinet/ip_var.h> 106 #include <netinet/in_systm.h> 107 #include <net/if_llatbl.h> 108 #ifdef INET 109 #include <netinet/ip.h> 110 #include <netinet/ip_icmp.h> 111 #endif /* INET */ 112 #include <netinet/ip6.h> 113 #include <netinet6/in6_var.h> 114 #include <netinet6/ip6_var.h> 115 #include <netinet/in_pcb.h> 116 #include <netinet/icmp6.h> 117 #include <netinet6/scope6_var.h> 118 #include <netinet6/in6_ifattach.h> 119 #include <netinet6/mld6_var.h> 120 #include <netinet6/nd6.h> 121 #include <netinet6/in6_rss.h> 122 123 #include <netipsec/ipsec_support.h> 124 125 #include <netinet6/ip6protosw.h> 126 127 extern struct domain inet6domain; 128 129 u_char ip6_protox[IPPROTO_MAX]; 130 VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead); 131 VNET_DEFINE(struct in6_ifaddrlisthead *, in6_ifaddrhashtbl); 132 VNET_DEFINE(u_long, in6_ifaddrhmask); 133 134 static struct netisr_handler ip6_nh = { 135 .nh_name = "ip6", 136 .nh_handler = ip6_input, 137 .nh_proto = NETISR_IPV6, 138 #ifdef RSS 139 .nh_m2cpuid = rss_soft_m2cpuid_v6, 140 .nh_policy = NETISR_POLICY_CPU, 141 .nh_dispatch = NETISR_DISPATCH_HYBRID, 142 #else 143 .nh_policy = NETISR_POLICY_FLOW, 144 #endif 145 }; 146 147 static int 148 sysctl_netinet6_intr_queue_maxlen(SYSCTL_HANDLER_ARGS) 149 { 150 int error, qlimit; 151 152 netisr_getqlimit(&ip6_nh, &qlimit); 153 error = sysctl_handle_int(oidp, &qlimit, 0, req); 154 if (error || !req->newptr) 155 return (error); 156 if (qlimit < 1) 157 return (EINVAL); 158 return (netisr_setqlimit(&ip6_nh, qlimit)); 159 } 160 SYSCTL_DECL(_net_inet6_ip6); 161 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRQMAXLEN, intr_queue_maxlen, 162 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet6_intr_queue_maxlen, "I", 163 "Maximum size of the IPv6 input queue"); 164 165 #ifdef RSS 166 static struct netisr_handler ip6_direct_nh = { 167 .nh_name = "ip6_direct", 168 .nh_handler = ip6_direct_input, 169 .nh_proto = NETISR_IPV6_DIRECT, 170 .nh_m2cpuid = rss_soft_m2cpuid_v6, 171 .nh_policy = NETISR_POLICY_CPU, 172 .nh_dispatch = NETISR_DISPATCH_HYBRID, 173 }; 174 175 static int 176 sysctl_netinet6_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS) 177 { 178 int error, qlimit; 179 180 netisr_getqlimit(&ip6_direct_nh, &qlimit); 181 error = sysctl_handle_int(oidp, &qlimit, 0, req); 182 if (error || !req->newptr) 183 return (error); 184 if (qlimit < 1) 185 return (EINVAL); 186 return (netisr_setqlimit(&ip6_direct_nh, qlimit)); 187 } 188 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRDQMAXLEN, intr_direct_queue_maxlen, 189 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet6_intr_direct_queue_maxlen, 190 "I", "Maximum size of the IPv6 direct input queue"); 191 192 #endif 193 194 VNET_DEFINE(pfil_head_t, inet6_pfil_head); 195 196 VNET_PCPUSTAT_DEFINE(struct ip6stat, ip6stat); 197 VNET_PCPUSTAT_SYSINIT(ip6stat); 198 #ifdef VIMAGE 199 VNET_PCPUSTAT_SYSUNINIT(ip6stat); 200 #endif /* VIMAGE */ 201 202 struct rmlock in6_ifaddr_lock; 203 RM_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock"); 204 205 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *); 206 #ifdef PULLDOWN_TEST 207 static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int); 208 #endif 209 210 /* 211 * IP6 initialization: fill in IP6 protocol switch table. 212 * All protocols not implemented in kernel go to raw IP6 protocol handler. 213 */ 214 void 215 ip6_init(void) 216 { 217 struct pfil_head_args args; 218 struct protosw *pr; 219 int i; 220 221 TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal", 222 &V_ip6_auto_linklocal); 223 TUNABLE_INT_FETCH("net.inet6.ip6.accept_rtadv", &V_ip6_accept_rtadv); 224 TUNABLE_INT_FETCH("net.inet6.ip6.no_radr", &V_ip6_no_radr); 225 226 CK_STAILQ_INIT(&V_in6_ifaddrhead); 227 V_in6_ifaddrhashtbl = hashinit(IN6ADDR_NHASH, M_IFADDR, 228 &V_in6_ifaddrhmask); 229 230 /* Initialize packet filter hooks. */ 231 args.pa_version = PFIL_VERSION; 232 args.pa_flags = PFIL_IN | PFIL_OUT; 233 args.pa_type = PFIL_TYPE_IP6; 234 args.pa_headname = PFIL_INET6_NAME; 235 V_inet6_pfil_head = pfil_head_register(&args); 236 237 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET6, 238 &V_ipsec_hhh_in[HHOOK_IPSEC_INET6], 239 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 240 printf("%s: WARNING: unable to register input helper hook\n", 241 __func__); 242 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET6, 243 &V_ipsec_hhh_out[HHOOK_IPSEC_INET6], 244 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 245 printf("%s: WARNING: unable to register output helper hook\n", 246 __func__); 247 248 scope6_init(); 249 addrsel_policy_init(); 250 nd6_init(); 251 frag6_init(); 252 253 V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR; 254 255 /* Skip global initialization stuff for non-default instances. */ 256 #ifdef VIMAGE 257 if (!IS_DEFAULT_VNET(curvnet)) { 258 netisr_register_vnet(&ip6_nh); 259 #ifdef RSS 260 netisr_register_vnet(&ip6_direct_nh); 261 #endif 262 return; 263 } 264 #endif 265 266 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 267 if (pr == NULL) 268 panic("ip6_init"); 269 270 /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */ 271 for (i = 0; i < IPPROTO_MAX; i++) 272 ip6_protox[i] = pr - inet6sw; 273 /* 274 * Cycle through IP protocols and put them into the appropriate place 275 * in ip6_protox[]. 276 */ 277 for (pr = inet6domain.dom_protosw; 278 pr < inet6domain.dom_protoswNPROTOSW; pr++) 279 if (pr->pr_domain->dom_family == PF_INET6 && 280 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) { 281 /* Be careful to only index valid IP protocols. */ 282 if (pr->pr_protocol < IPPROTO_MAX) 283 ip6_protox[pr->pr_protocol] = pr - inet6sw; 284 } 285 286 netisr_register(&ip6_nh); 287 #ifdef RSS 288 netisr_register(&ip6_direct_nh); 289 #endif 290 } 291 292 /* 293 * The protocol to be inserted into ip6_protox[] must be already registered 294 * in inet6sw[], either statically or through pf_proto_register(). 295 */ 296 int 297 ip6proto_register(short ip6proto) 298 { 299 struct protosw *pr; 300 301 /* Sanity checks. */ 302 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 303 return (EPROTONOSUPPORT); 304 305 /* 306 * The protocol slot must not be occupied by another protocol 307 * already. An index pointing to IPPROTO_RAW is unused. 308 */ 309 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 310 if (pr == NULL) 311 return (EPFNOSUPPORT); 312 if (ip6_protox[ip6proto] != pr - inet6sw) /* IPPROTO_RAW */ 313 return (EEXIST); 314 315 /* 316 * Find the protocol position in inet6sw[] and set the index. 317 */ 318 for (pr = inet6domain.dom_protosw; 319 pr < inet6domain.dom_protoswNPROTOSW; pr++) { 320 if (pr->pr_domain->dom_family == PF_INET6 && 321 pr->pr_protocol && pr->pr_protocol == ip6proto) { 322 ip6_protox[pr->pr_protocol] = pr - inet6sw; 323 return (0); 324 } 325 } 326 return (EPROTONOSUPPORT); 327 } 328 329 int 330 ip6proto_unregister(short ip6proto) 331 { 332 struct protosw *pr; 333 334 /* Sanity checks. */ 335 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 336 return (EPROTONOSUPPORT); 337 338 /* Check if the protocol was indeed registered. */ 339 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 340 if (pr == NULL) 341 return (EPFNOSUPPORT); 342 if (ip6_protox[ip6proto] == pr - inet6sw) /* IPPROTO_RAW */ 343 return (ENOENT); 344 345 /* Reset the protocol slot to IPPROTO_RAW. */ 346 ip6_protox[ip6proto] = pr - inet6sw; 347 return (0); 348 } 349 350 #ifdef VIMAGE 351 static void 352 ip6_destroy(void *unused __unused) 353 { 354 struct ifaddr *ifa, *nifa; 355 struct ifnet *ifp; 356 int error; 357 358 #ifdef RSS 359 netisr_unregister_vnet(&ip6_direct_nh); 360 #endif 361 netisr_unregister_vnet(&ip6_nh); 362 363 pfil_head_unregister(V_inet6_pfil_head); 364 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET6]); 365 if (error != 0) { 366 printf("%s: WARNING: unable to deregister input helper hook " 367 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET6: " 368 "error %d returned\n", __func__, error); 369 } 370 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET6]); 371 if (error != 0) { 372 printf("%s: WARNING: unable to deregister output helper hook " 373 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET6: " 374 "error %d returned\n", __func__, error); 375 } 376 377 /* Cleanup addresses. */ 378 IFNET_RLOCK(); 379 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) { 380 /* Cannot lock here - lock recursion. */ 381 /* IF_ADDR_LOCK(ifp); */ 382 CK_STAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, nifa) { 383 384 if (ifa->ifa_addr->sa_family != AF_INET6) 385 continue; 386 in6_purgeaddr(ifa); 387 } 388 /* IF_ADDR_UNLOCK(ifp); */ 389 in6_ifdetach_destroy(ifp); 390 mld_domifdetach(ifp); 391 /* Make sure any routes are gone as well. */ 392 rt_flushifroutes_af(ifp, AF_INET6); 393 } 394 IFNET_RUNLOCK(); 395 396 nd6_destroy(); 397 in6_ifattach_destroy(); 398 399 hashdestroy(V_in6_ifaddrhashtbl, M_IFADDR, V_in6_ifaddrhmask); 400 } 401 402 VNET_SYSUNINIT(inet6, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_destroy, NULL); 403 #endif 404 405 static int 406 ip6_input_hbh(struct mbuf *m, uint32_t *plen, uint32_t *rtalert, int *off, 407 int *nxt, int *ours) 408 { 409 struct ip6_hdr *ip6; 410 struct ip6_hbh *hbh; 411 412 if (ip6_hopopts_input(plen, rtalert, &m, off)) { 413 #if 0 /*touches NULL pointer*/ 414 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 415 #endif 416 goto out; /* m have already been freed */ 417 } 418 419 /* adjust pointer */ 420 ip6 = mtod(m, struct ip6_hdr *); 421 422 /* 423 * if the payload length field is 0 and the next header field 424 * indicates Hop-by-Hop Options header, then a Jumbo Payload 425 * option MUST be included. 426 */ 427 if (ip6->ip6_plen == 0 && *plen == 0) { 428 /* 429 * Note that if a valid jumbo payload option is 430 * contained, ip6_hopopts_input() must set a valid 431 * (non-zero) payload length to the variable plen. 432 */ 433 IP6STAT_INC(ip6s_badoptions); 434 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 435 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 436 icmp6_error(m, ICMP6_PARAM_PROB, 437 ICMP6_PARAMPROB_HEADER, 438 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 439 goto out; 440 } 441 #ifndef PULLDOWN_TEST 442 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 443 hbh = (struct ip6_hbh *)(ip6 + 1); 444 #else 445 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 446 sizeof(struct ip6_hbh)); 447 if (hbh == NULL) { 448 IP6STAT_INC(ip6s_tooshort); 449 goto out; 450 } 451 #endif 452 *nxt = hbh->ip6h_nxt; 453 454 /* 455 * If we are acting as a router and the packet contains a 456 * router alert option, see if we know the option value. 457 * Currently, we only support the option value for MLD, in which 458 * case we should pass the packet to the multicast routing 459 * daemon. 460 */ 461 if (*rtalert != ~0) { 462 switch (*rtalert) { 463 case IP6OPT_RTALERT_MLD: 464 if (V_ip6_forwarding) 465 *ours = 1; 466 break; 467 default: 468 /* 469 * RFC2711 requires unrecognized values must be 470 * silently ignored. 471 */ 472 break; 473 } 474 } 475 476 return (0); 477 478 out: 479 return (1); 480 } 481 482 #ifdef RSS 483 /* 484 * IPv6 direct input routine. 485 * 486 * This is called when reinjecting completed fragments where 487 * all of the previous checking and book-keeping has been done. 488 */ 489 void 490 ip6_direct_input(struct mbuf *m) 491 { 492 int off, nxt; 493 int nest; 494 struct m_tag *mtag; 495 struct ip6_direct_ctx *ip6dc; 496 497 mtag = m_tag_locate(m, MTAG_ABI_IPV6, IPV6_TAG_DIRECT, NULL); 498 KASSERT(mtag != NULL, ("Reinjected packet w/o direct ctx tag!")); 499 500 ip6dc = (struct ip6_direct_ctx *)(mtag + 1); 501 nxt = ip6dc->ip6dc_nxt; 502 off = ip6dc->ip6dc_off; 503 504 nest = 0; 505 506 m_tag_delete(m, mtag); 507 508 while (nxt != IPPROTO_DONE) { 509 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 510 IP6STAT_INC(ip6s_toomanyhdr); 511 goto bad; 512 } 513 514 /* 515 * protection against faulty packet - there should be 516 * more sanity checks in header chain processing. 517 */ 518 if (m->m_pkthdr.len < off) { 519 IP6STAT_INC(ip6s_tooshort); 520 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 521 goto bad; 522 } 523 524 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 525 if (IPSEC_ENABLED(ipv6)) { 526 if (IPSEC_INPUT(ipv6, m, off, nxt) != 0) 527 return; 528 } 529 #endif /* IPSEC */ 530 531 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 532 } 533 return; 534 bad: 535 m_freem(m); 536 } 537 #endif 538 539 void 540 ip6_input(struct mbuf *m) 541 { 542 struct in6_addr odst; 543 struct ip6_hdr *ip6; 544 struct in6_ifaddr *ia; 545 struct ifnet *rcvif; 546 u_int32_t plen; 547 u_int32_t rtalert = ~0; 548 int off = sizeof(struct ip6_hdr), nest; 549 int nxt, ours = 0; 550 int srcrt = 0; 551 552 /* 553 * Drop the packet if IPv6 operation is disabled on the interface. 554 */ 555 rcvif = m->m_pkthdr.rcvif; 556 if ((ND_IFINFO(rcvif)->flags & ND6_IFF_IFDISABLED)) 557 goto bad; 558 559 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 560 /* 561 * should the inner packet be considered authentic? 562 * see comment in ah4_input(). 563 * NB: m cannot be NULL when passed to the input routine 564 */ 565 566 m->m_flags &= ~M_AUTHIPHDR; 567 m->m_flags &= ~M_AUTHIPDGM; 568 569 #endif /* IPSEC */ 570 571 if (m->m_flags & M_FASTFWD_OURS) { 572 /* 573 * Firewall changed destination to local. 574 */ 575 ip6 = mtod(m, struct ip6_hdr *); 576 goto passin; 577 } 578 579 /* 580 * mbuf statistics 581 */ 582 if (m->m_flags & M_EXT) { 583 if (m->m_next) 584 IP6STAT_INC(ip6s_mext2m); 585 else 586 IP6STAT_INC(ip6s_mext1); 587 } else { 588 if (m->m_next) { 589 if (m->m_flags & M_LOOP) { 590 IP6STAT_INC(ip6s_m2m[V_loif->if_index]); 591 } else if (rcvif->if_index < IP6S_M2MMAX) 592 IP6STAT_INC(ip6s_m2m[rcvif->if_index]); 593 else 594 IP6STAT_INC(ip6s_m2m[0]); 595 } else 596 IP6STAT_INC(ip6s_m1); 597 } 598 599 in6_ifstat_inc(rcvif, ifs6_in_receive); 600 IP6STAT_INC(ip6s_total); 601 602 #ifndef PULLDOWN_TEST 603 /* 604 * L2 bridge code and some other code can return mbuf chain 605 * that does not conform to KAME requirement. too bad. 606 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? 607 */ 608 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { 609 struct mbuf *n; 610 611 if (m->m_pkthdr.len > MHLEN) 612 n = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 613 else 614 n = m_gethdr(M_NOWAIT, MT_DATA); 615 if (n == NULL) 616 goto bad; 617 618 m_move_pkthdr(n, m); 619 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t)); 620 n->m_len = n->m_pkthdr.len; 621 m_freem(m); 622 m = n; 623 } 624 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */); 625 #endif 626 627 if (m->m_len < sizeof(struct ip6_hdr)) { 628 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 629 IP6STAT_INC(ip6s_toosmall); 630 in6_ifstat_inc(rcvif, ifs6_in_hdrerr); 631 goto bad; 632 } 633 } 634 635 ip6 = mtod(m, struct ip6_hdr *); 636 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 637 IP6STAT_INC(ip6s_badvers); 638 in6_ifstat_inc(rcvif, ifs6_in_hdrerr); 639 goto bad; 640 } 641 642 IP6STAT_INC(ip6s_nxthist[ip6->ip6_nxt]); 643 IP_PROBE(receive, NULL, NULL, ip6, rcvif, NULL, ip6); 644 645 /* 646 * Check against address spoofing/corruption. 647 */ 648 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 649 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 650 /* 651 * XXX: "badscope" is not very suitable for a multicast source. 652 */ 653 IP6STAT_INC(ip6s_badscope); 654 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 655 goto bad; 656 } 657 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && 658 !(m->m_flags & M_LOOP)) { 659 /* 660 * In this case, the packet should come from the loopback 661 * interface. However, we cannot just check the if_flags, 662 * because ip6_mloopback() passes the "actual" interface 663 * as the outgoing/incoming interface. 664 */ 665 IP6STAT_INC(ip6s_badscope); 666 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 667 goto bad; 668 } 669 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 670 IPV6_ADDR_MC_SCOPE(&ip6->ip6_dst) == 0) { 671 /* 672 * RFC4291 2.7: 673 * Nodes must not originate a packet to a multicast address 674 * whose scop field contains the reserved value 0; if such 675 * a packet is received, it must be silently dropped. 676 */ 677 IP6STAT_INC(ip6s_badscope); 678 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 679 goto bad; 680 } 681 #ifdef ALTQ 682 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 683 /* packet is dropped by traffic conditioner */ 684 return; 685 } 686 #endif 687 /* 688 * The following check is not documented in specs. A malicious 689 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 690 * and bypass security checks (act as if it was from 127.0.0.1 by using 691 * IPv6 src ::ffff:127.0.0.1). Be cautious. 692 * 693 * This check chokes if we are in an SIIT cloud. As none of BSDs 694 * support IPv4-less kernel compilation, we cannot support SIIT 695 * environment at all. So, it makes more sense for us to reject any 696 * malicious packets for non-SIIT environment, than try to do a 697 * partial support for SIIT environment. 698 */ 699 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 700 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 701 IP6STAT_INC(ip6s_badscope); 702 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 703 goto bad; 704 } 705 #if 0 706 /* 707 * Reject packets with IPv4 compatible addresses (auto tunnel). 708 * 709 * The code forbids auto tunnel relay case in RFC1933 (the check is 710 * stronger than RFC1933). We may want to re-enable it if mech-xx 711 * is revised to forbid relaying case. 712 */ 713 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 714 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 715 IP6STAT_INC(ip6s_badscope); 716 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 717 goto bad; 718 } 719 #endif 720 /* 721 * Try to forward the packet, but if we fail continue. 722 * ip6_tryforward() does not generate redirects, so fall 723 * through to normal processing if redirects are required. 724 * ip6_tryforward() does inbound and outbound packet firewall 725 * processing. If firewall has decided that destination becomes 726 * our local address, it sets M_FASTFWD_OURS flag. In this 727 * case skip another inbound firewall processing and update 728 * ip6 pointer. 729 */ 730 if (V_ip6_forwarding != 0 && V_ip6_sendredirects == 0 731 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 732 && (!IPSEC_ENABLED(ipv6) || 733 IPSEC_CAPS(ipv6, m, IPSEC_CAP_OPERABLE) == 0) 734 #endif 735 ) { 736 if ((m = ip6_tryforward(m)) == NULL) 737 return; 738 if (m->m_flags & M_FASTFWD_OURS) { 739 ip6 = mtod(m, struct ip6_hdr *); 740 goto passin; 741 } 742 } 743 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 744 /* 745 * Bypass packet filtering for packets previously handled by IPsec. 746 */ 747 if (IPSEC_ENABLED(ipv6) && 748 IPSEC_CAPS(ipv6, m, IPSEC_CAP_BYPASS_FILTER) != 0) 749 goto passin; 750 #endif 751 /* 752 * Run through list of hooks for input packets. 753 * 754 * NB: Beware of the destination address changing 755 * (e.g. by NAT rewriting). When this happens, 756 * tell ip6_forward to do the right thing. 757 */ 758 759 /* Jump over all PFIL processing if hooks are not active. */ 760 if (!PFIL_HOOKED_IN(V_inet6_pfil_head)) 761 goto passin; 762 763 odst = ip6->ip6_dst; 764 if (pfil_run_hooks(V_inet6_pfil_head, &m, m->m_pkthdr.rcvif, PFIL_IN, 765 NULL) != PFIL_PASS) 766 return; 767 ip6 = mtod(m, struct ip6_hdr *); 768 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 769 if ((m->m_flags & (M_IP6_NEXTHOP | M_FASTFWD_OURS)) == M_IP6_NEXTHOP && 770 m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) { 771 /* 772 * Directly ship the packet on. This allows forwarding 773 * packets originally destined to us to some other directly 774 * connected host. 775 */ 776 ip6_forward(m, 1); 777 return; 778 } 779 780 passin: 781 /* 782 * Disambiguate address scope zones (if there is ambiguity). 783 * We first make sure that the original source or destination address 784 * is not in our internal form for scoped addresses. Such addresses 785 * are not necessarily invalid spec-wise, but we cannot accept them due 786 * to the usage conflict. 787 * in6_setscope() then also checks and rejects the cases where src or 788 * dst are the loopback address and the receiving interface 789 * is not loopback. 790 */ 791 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) { 792 IP6STAT_INC(ip6s_badscope); /* XXX */ 793 goto bad; 794 } 795 if (in6_setscope(&ip6->ip6_src, rcvif, NULL) || 796 in6_setscope(&ip6->ip6_dst, rcvif, NULL)) { 797 IP6STAT_INC(ip6s_badscope); 798 goto bad; 799 } 800 if (m->m_flags & M_FASTFWD_OURS) { 801 m->m_flags &= ~M_FASTFWD_OURS; 802 ours = 1; 803 goto hbhcheck; 804 } 805 /* 806 * Multicast check. Assume packet is for us to avoid 807 * prematurely taking locks. 808 */ 809 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 810 ours = 1; 811 in6_ifstat_inc(rcvif, ifs6_in_mcast); 812 goto hbhcheck; 813 } 814 /* 815 * Unicast check 816 * XXX: For now we keep link-local IPv6 addresses with embedded 817 * scope zone id, therefore we use zero zoneid here. 818 */ 819 ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */); 820 if (ia != NULL) { 821 if (ia->ia6_flags & IN6_IFF_NOTREADY) { 822 char ip6bufs[INET6_ADDRSTRLEN]; 823 char ip6bufd[INET6_ADDRSTRLEN]; 824 /* address is not ready, so discard the packet. */ 825 nd6log((LOG_INFO, 826 "ip6_input: packet to an unready address %s->%s\n", 827 ip6_sprintf(ip6bufs, &ip6->ip6_src), 828 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 829 ifa_free(&ia->ia_ifa); 830 goto bad; 831 } 832 /* Count the packet in the ip address stats */ 833 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1); 834 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len); 835 ifa_free(&ia->ia_ifa); 836 ours = 1; 837 goto hbhcheck; 838 } 839 840 /* 841 * Now there is no reason to process the packet if it's not our own 842 * and we're not a router. 843 */ 844 if (!V_ip6_forwarding) { 845 IP6STAT_INC(ip6s_cantforward); 846 goto bad; 847 } 848 849 hbhcheck: 850 /* 851 * Process Hop-by-Hop options header if it's contained. 852 * m may be modified in ip6_hopopts_input(). 853 * If a JumboPayload option is included, plen will also be modified. 854 */ 855 plen = (u_int32_t)ntohs(ip6->ip6_plen); 856 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 857 if (ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours) != 0) 858 return; 859 } else 860 nxt = ip6->ip6_nxt; 861 862 /* 863 * Use mbuf flags to propagate Router Alert option to 864 * ICMPv6 layer, as hop-by-hop options have been stripped. 865 */ 866 if (rtalert != ~0) 867 m->m_flags |= M_RTALERT_MLD; 868 869 /* 870 * Check that the amount of data in the buffers 871 * is as at least much as the IPv6 header would have us expect. 872 * Trim mbufs if longer than we expect. 873 * Drop packet if shorter than we expect. 874 */ 875 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 876 IP6STAT_INC(ip6s_tooshort); 877 in6_ifstat_inc(rcvif, ifs6_in_truncated); 878 goto bad; 879 } 880 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 881 if (m->m_len == m->m_pkthdr.len) { 882 m->m_len = sizeof(struct ip6_hdr) + plen; 883 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 884 } else 885 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 886 } 887 888 /* 889 * Forward if desirable. 890 */ 891 if (V_ip6_mrouter && 892 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 893 /* 894 * If we are acting as a multicast router, all 895 * incoming multicast packets are passed to the 896 * kernel-level multicast forwarding function. 897 * The packet is returned (relatively) intact; if 898 * ip6_mforward() returns a non-zero value, the packet 899 * must be discarded, else it may be accepted below. 900 * 901 * XXX TODO: Check hlim and multicast scope here to avoid 902 * unnecessarily calling into ip6_mforward(). 903 */ 904 if (ip6_mforward && ip6_mforward(ip6, rcvif, m)) { 905 IP6STAT_INC(ip6s_cantforward); 906 goto bad; 907 } 908 } else if (!ours) { 909 ip6_forward(m, srcrt); 910 return; 911 } 912 913 ip6 = mtod(m, struct ip6_hdr *); 914 915 /* 916 * Malicious party may be able to use IPv4 mapped addr to confuse 917 * tcp/udp stack and bypass security checks (act as if it was from 918 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 919 * 920 * For SIIT end node behavior, you may want to disable the check. 921 * However, you will become vulnerable to attacks using IPv4 mapped 922 * source. 923 */ 924 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 925 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 926 IP6STAT_INC(ip6s_badscope); 927 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 928 goto bad; 929 } 930 931 /* 932 * Tell launch routine the next header 933 */ 934 IP6STAT_INC(ip6s_delivered); 935 in6_ifstat_inc(rcvif, ifs6_in_deliver); 936 nest = 0; 937 938 while (nxt != IPPROTO_DONE) { 939 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 940 IP6STAT_INC(ip6s_toomanyhdr); 941 goto bad; 942 } 943 944 /* 945 * protection against faulty packet - there should be 946 * more sanity checks in header chain processing. 947 */ 948 if (m->m_pkthdr.len < off) { 949 IP6STAT_INC(ip6s_tooshort); 950 in6_ifstat_inc(rcvif, ifs6_in_truncated); 951 goto bad; 952 } 953 954 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 955 if (IPSEC_ENABLED(ipv6)) { 956 if (IPSEC_INPUT(ipv6, m, off, nxt) != 0) 957 return; 958 } 959 #endif /* IPSEC */ 960 961 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 962 } 963 return; 964 bad: 965 in6_ifstat_inc(rcvif, ifs6_in_discard); 966 if (m != NULL) 967 m_freem(m); 968 } 969 970 /* 971 * Hop-by-Hop options header processing. If a valid jumbo payload option is 972 * included, the real payload length will be stored in plenp. 973 * 974 * rtalertp - XXX: should be stored more smart way 975 */ 976 static int 977 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp, 978 struct mbuf **mp, int *offp) 979 { 980 struct mbuf *m = *mp; 981 int off = *offp, hbhlen; 982 struct ip6_hbh *hbh; 983 984 /* validation of the length of the header */ 985 #ifndef PULLDOWN_TEST 986 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 987 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 988 hbhlen = (hbh->ip6h_len + 1) << 3; 989 990 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 991 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 992 #else 993 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 994 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 995 if (hbh == NULL) { 996 IP6STAT_INC(ip6s_tooshort); 997 return -1; 998 } 999 hbhlen = (hbh->ip6h_len + 1) << 3; 1000 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 1001 hbhlen); 1002 if (hbh == NULL) { 1003 IP6STAT_INC(ip6s_tooshort); 1004 return -1; 1005 } 1006 #endif 1007 off += hbhlen; 1008 hbhlen -= sizeof(struct ip6_hbh); 1009 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 1010 hbhlen, rtalertp, plenp) < 0) 1011 return (-1); 1012 1013 *offp = off; 1014 *mp = m; 1015 return (0); 1016 } 1017 1018 /* 1019 * Search header for all Hop-by-hop options and process each option. 1020 * This function is separate from ip6_hopopts_input() in order to 1021 * handle a case where the sending node itself process its hop-by-hop 1022 * options header. In such a case, the function is called from ip6_output(). 1023 * 1024 * The function assumes that hbh header is located right after the IPv6 header 1025 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 1026 * opthead + hbhlen is located in contiguous memory region. 1027 */ 1028 int 1029 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 1030 u_int32_t *rtalertp, u_int32_t *plenp) 1031 { 1032 struct ip6_hdr *ip6; 1033 int optlen = 0; 1034 u_int8_t *opt = opthead; 1035 u_int16_t rtalert_val; 1036 u_int32_t jumboplen; 1037 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 1038 1039 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 1040 switch (*opt) { 1041 case IP6OPT_PAD1: 1042 optlen = 1; 1043 break; 1044 case IP6OPT_PADN: 1045 if (hbhlen < IP6OPT_MINLEN) { 1046 IP6STAT_INC(ip6s_toosmall); 1047 goto bad; 1048 } 1049 optlen = *(opt + 1) + 2; 1050 break; 1051 case IP6OPT_ROUTER_ALERT: 1052 /* XXX may need check for alignment */ 1053 if (hbhlen < IP6OPT_RTALERT_LEN) { 1054 IP6STAT_INC(ip6s_toosmall); 1055 goto bad; 1056 } 1057 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 1058 /* XXX stat */ 1059 icmp6_error(m, ICMP6_PARAM_PROB, 1060 ICMP6_PARAMPROB_HEADER, 1061 erroff + opt + 1 - opthead); 1062 return (-1); 1063 } 1064 optlen = IP6OPT_RTALERT_LEN; 1065 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 1066 *rtalertp = ntohs(rtalert_val); 1067 break; 1068 case IP6OPT_JUMBO: 1069 /* XXX may need check for alignment */ 1070 if (hbhlen < IP6OPT_JUMBO_LEN) { 1071 IP6STAT_INC(ip6s_toosmall); 1072 goto bad; 1073 } 1074 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 1075 /* XXX stat */ 1076 icmp6_error(m, ICMP6_PARAM_PROB, 1077 ICMP6_PARAMPROB_HEADER, 1078 erroff + opt + 1 - opthead); 1079 return (-1); 1080 } 1081 optlen = IP6OPT_JUMBO_LEN; 1082 1083 /* 1084 * IPv6 packets that have non 0 payload length 1085 * must not contain a jumbo payload option. 1086 */ 1087 ip6 = mtod(m, struct ip6_hdr *); 1088 if (ip6->ip6_plen) { 1089 IP6STAT_INC(ip6s_badoptions); 1090 icmp6_error(m, ICMP6_PARAM_PROB, 1091 ICMP6_PARAMPROB_HEADER, 1092 erroff + opt - opthead); 1093 return (-1); 1094 } 1095 1096 /* 1097 * We may see jumbolen in unaligned location, so 1098 * we'd need to perform bcopy(). 1099 */ 1100 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 1101 jumboplen = (u_int32_t)htonl(jumboplen); 1102 1103 #if 1 1104 /* 1105 * if there are multiple jumbo payload options, 1106 * *plenp will be non-zero and the packet will be 1107 * rejected. 1108 * the behavior may need some debate in ipngwg - 1109 * multiple options does not make sense, however, 1110 * there's no explicit mention in specification. 1111 */ 1112 if (*plenp != 0) { 1113 IP6STAT_INC(ip6s_badoptions); 1114 icmp6_error(m, ICMP6_PARAM_PROB, 1115 ICMP6_PARAMPROB_HEADER, 1116 erroff + opt + 2 - opthead); 1117 return (-1); 1118 } 1119 #endif 1120 1121 /* 1122 * jumbo payload length must be larger than 65535. 1123 */ 1124 if (jumboplen <= IPV6_MAXPACKET) { 1125 IP6STAT_INC(ip6s_badoptions); 1126 icmp6_error(m, ICMP6_PARAM_PROB, 1127 ICMP6_PARAMPROB_HEADER, 1128 erroff + opt + 2 - opthead); 1129 return (-1); 1130 } 1131 *plenp = jumboplen; 1132 1133 break; 1134 default: /* unknown option */ 1135 if (hbhlen < IP6OPT_MINLEN) { 1136 IP6STAT_INC(ip6s_toosmall); 1137 goto bad; 1138 } 1139 optlen = ip6_unknown_opt(opt, m, 1140 erroff + opt - opthead); 1141 if (optlen == -1) 1142 return (-1); 1143 optlen += 2; 1144 break; 1145 } 1146 } 1147 1148 return (0); 1149 1150 bad: 1151 m_freem(m); 1152 return (-1); 1153 } 1154 1155 /* 1156 * Unknown option processing. 1157 * The third argument `off' is the offset from the IPv6 header to the option, 1158 * which is necessary if the IPv6 header the and option header and IPv6 header 1159 * is not contiguous in order to return an ICMPv6 error. 1160 */ 1161 int 1162 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 1163 { 1164 struct ip6_hdr *ip6; 1165 1166 switch (IP6OPT_TYPE(*optp)) { 1167 case IP6OPT_TYPE_SKIP: /* ignore the option */ 1168 return ((int)*(optp + 1)); 1169 case IP6OPT_TYPE_DISCARD: /* silently discard */ 1170 m_freem(m); 1171 return (-1); 1172 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 1173 IP6STAT_INC(ip6s_badoptions); 1174 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 1175 return (-1); 1176 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 1177 IP6STAT_INC(ip6s_badoptions); 1178 ip6 = mtod(m, struct ip6_hdr *); 1179 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 1180 (m->m_flags & (M_BCAST|M_MCAST))) 1181 m_freem(m); 1182 else 1183 icmp6_error(m, ICMP6_PARAM_PROB, 1184 ICMP6_PARAMPROB_OPTION, off); 1185 return (-1); 1186 } 1187 1188 m_freem(m); /* XXX: NOTREACHED */ 1189 return (-1); 1190 } 1191 1192 /* 1193 * Create the "control" list for this pcb. 1194 * These functions will not modify mbuf chain at all. 1195 * 1196 * With KAME mbuf chain restriction: 1197 * The routine will be called from upper layer handlers like tcp6_input(). 1198 * Thus the routine assumes that the caller (tcp6_input) have already 1199 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1200 * very first mbuf on the mbuf chain. 1201 * 1202 * ip6_savecontrol_v4 will handle those options that are possible to be 1203 * set on a v4-mapped socket. 1204 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those 1205 * options and handle the v6-only ones itself. 1206 */ 1207 struct mbuf ** 1208 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp, 1209 int *v4only) 1210 { 1211 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1212 1213 #ifdef SO_TIMESTAMP 1214 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) { 1215 union { 1216 struct timeval tv; 1217 struct bintime bt; 1218 struct timespec ts; 1219 } t; 1220 struct bintime boottimebin, bt1; 1221 struct timespec ts1; 1222 bool stamped; 1223 1224 stamped = false; 1225 switch (inp->inp_socket->so_ts_clock) { 1226 case SO_TS_REALTIME_MICRO: 1227 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1228 M_TSTMP)) { 1229 mbuf_tstmp2timespec(m, &ts1); 1230 timespec2bintime(&ts1, &bt1); 1231 getboottimebin(&boottimebin); 1232 bintime_add(&bt1, &boottimebin); 1233 bintime2timeval(&bt1, &t.tv); 1234 } else { 1235 microtime(&t.tv); 1236 } 1237 *mp = sbcreatecontrol((caddr_t) &t.tv, sizeof(t.tv), 1238 SCM_TIMESTAMP, SOL_SOCKET); 1239 if (*mp != NULL) { 1240 mp = &(*mp)->m_next; 1241 stamped = true; 1242 } 1243 break; 1244 1245 case SO_TS_BINTIME: 1246 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1247 M_TSTMP)) { 1248 mbuf_tstmp2timespec(m, &ts1); 1249 timespec2bintime(&ts1, &t.bt); 1250 getboottimebin(&boottimebin); 1251 bintime_add(&t.bt, &boottimebin); 1252 } else { 1253 bintime(&t.bt); 1254 } 1255 *mp = sbcreatecontrol((caddr_t)&t.bt, sizeof(t.bt), 1256 SCM_BINTIME, SOL_SOCKET); 1257 if (*mp != NULL) { 1258 mp = &(*mp)->m_next; 1259 stamped = true; 1260 } 1261 break; 1262 1263 case SO_TS_REALTIME: 1264 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1265 M_TSTMP)) { 1266 mbuf_tstmp2timespec(m, &t.ts); 1267 getboottimebin(&boottimebin); 1268 bintime2timespec(&boottimebin, &ts1); 1269 timespecadd(&t.ts, &ts1, &t.ts); 1270 } else { 1271 nanotime(&t.ts); 1272 } 1273 *mp = sbcreatecontrol((caddr_t)&t.ts, sizeof(t.ts), 1274 SCM_REALTIME, SOL_SOCKET); 1275 if (*mp != NULL) { 1276 mp = &(*mp)->m_next; 1277 stamped = true; 1278 } 1279 break; 1280 1281 case SO_TS_MONOTONIC: 1282 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1283 M_TSTMP)) 1284 mbuf_tstmp2timespec(m, &t.ts); 1285 else 1286 nanouptime(&t.ts); 1287 *mp = sbcreatecontrol((caddr_t)&t.ts, sizeof(t.ts), 1288 SCM_MONOTONIC, SOL_SOCKET); 1289 if (*mp != NULL) { 1290 mp = &(*mp)->m_next; 1291 stamped = true; 1292 } 1293 break; 1294 1295 default: 1296 panic("unknown (corrupted) so_ts_clock"); 1297 } 1298 if (stamped && (m->m_flags & (M_PKTHDR | M_TSTMP)) == 1299 (M_PKTHDR | M_TSTMP)) { 1300 struct sock_timestamp_info sti; 1301 1302 bzero(&sti, sizeof(sti)); 1303 sti.st_info_flags = ST_INFO_HW; 1304 if ((m->m_flags & M_TSTMP_HPREC) != 0) 1305 sti.st_info_flags |= ST_INFO_HW_HPREC; 1306 *mp = sbcreatecontrol((caddr_t)&sti, sizeof(sti), 1307 SCM_TIME_INFO, SOL_SOCKET); 1308 if (*mp != NULL) 1309 mp = &(*mp)->m_next; 1310 } 1311 } 1312 #endif 1313 1314 #define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y)) 1315 /* RFC 2292 sec. 5 */ 1316 if ((inp->inp_flags & IN6P_PKTINFO) != 0) { 1317 struct in6_pktinfo pi6; 1318 1319 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1320 #ifdef INET 1321 struct ip *ip; 1322 1323 ip = mtod(m, struct ip *); 1324 pi6.ipi6_addr.s6_addr32[0] = 0; 1325 pi6.ipi6_addr.s6_addr32[1] = 0; 1326 pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP; 1327 pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr; 1328 #else 1329 /* We won't hit this code */ 1330 bzero(&pi6.ipi6_addr, sizeof(struct in6_addr)); 1331 #endif 1332 } else { 1333 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1334 in6_clearscope(&pi6.ipi6_addr); /* XXX */ 1335 } 1336 pi6.ipi6_ifindex = 1337 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0; 1338 1339 *mp = sbcreatecontrol((caddr_t) &pi6, 1340 sizeof(struct in6_pktinfo), 1341 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6); 1342 if (*mp) 1343 mp = &(*mp)->m_next; 1344 } 1345 1346 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) { 1347 int hlim; 1348 1349 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1350 #ifdef INET 1351 struct ip *ip; 1352 1353 ip = mtod(m, struct ip *); 1354 hlim = ip->ip_ttl; 1355 #else 1356 /* We won't hit this code */ 1357 hlim = 0; 1358 #endif 1359 } else { 1360 hlim = ip6->ip6_hlim & 0xff; 1361 } 1362 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 1363 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), 1364 IPPROTO_IPV6); 1365 if (*mp) 1366 mp = &(*mp)->m_next; 1367 } 1368 1369 if ((inp->inp_flags & IN6P_TCLASS) != 0) { 1370 int tclass; 1371 1372 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1373 #ifdef INET 1374 struct ip *ip; 1375 1376 ip = mtod(m, struct ip *); 1377 tclass = ip->ip_tos; 1378 #else 1379 /* We won't hit this code */ 1380 tclass = 0; 1381 #endif 1382 } else { 1383 u_int32_t flowinfo; 1384 1385 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1386 flowinfo >>= 20; 1387 tclass = flowinfo & 0xff; 1388 } 1389 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int), 1390 IPV6_TCLASS, IPPROTO_IPV6); 1391 if (*mp) 1392 mp = &(*mp)->m_next; 1393 } 1394 1395 if (v4only != NULL) { 1396 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1397 *v4only = 1; 1398 } else { 1399 *v4only = 0; 1400 } 1401 } 1402 1403 return (mp); 1404 } 1405 1406 void 1407 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 1408 { 1409 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1410 int v4only = 0; 1411 1412 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only); 1413 if (v4only) 1414 return; 1415 1416 /* 1417 * IPV6_HOPOPTS socket option. Recall that we required super-user 1418 * privilege for the option (see ip6_ctloutput), but it might be too 1419 * strict, since there might be some hop-by-hop options which can be 1420 * returned to normal user. 1421 * See also RFC 2292 section 6 (or RFC 3542 section 8). 1422 */ 1423 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 1424 /* 1425 * Check if a hop-by-hop options header is contatined in the 1426 * received packet, and if so, store the options as ancillary 1427 * data. Note that a hop-by-hop options header must be 1428 * just after the IPv6 header, which is assured through the 1429 * IPv6 input processing. 1430 */ 1431 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1432 struct ip6_hbh *hbh; 1433 int hbhlen = 0; 1434 #ifdef PULLDOWN_TEST 1435 struct mbuf *ext; 1436 #endif 1437 1438 #ifndef PULLDOWN_TEST 1439 hbh = (struct ip6_hbh *)(ip6 + 1); 1440 hbhlen = (hbh->ip6h_len + 1) << 3; 1441 #else 1442 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1443 ip6->ip6_nxt); 1444 if (ext == NULL) { 1445 IP6STAT_INC(ip6s_tooshort); 1446 return; 1447 } 1448 hbh = mtod(ext, struct ip6_hbh *); 1449 hbhlen = (hbh->ip6h_len + 1) << 3; 1450 if (hbhlen != ext->m_len) { 1451 m_freem(ext); 1452 IP6STAT_INC(ip6s_tooshort); 1453 return; 1454 } 1455 #endif 1456 1457 /* 1458 * XXX: We copy the whole header even if a 1459 * jumbo payload option is included, the option which 1460 * is to be removed before returning according to 1461 * RFC2292. 1462 * Note: this constraint is removed in RFC3542 1463 */ 1464 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1465 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS), 1466 IPPROTO_IPV6); 1467 if (*mp) 1468 mp = &(*mp)->m_next; 1469 #ifdef PULLDOWN_TEST 1470 m_freem(ext); 1471 #endif 1472 } 1473 } 1474 1475 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1476 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1477 1478 /* 1479 * Search for destination options headers or routing 1480 * header(s) through the header chain, and stores each 1481 * header as ancillary data. 1482 * Note that the order of the headers remains in 1483 * the chain of ancillary data. 1484 */ 1485 while (1) { /* is explicit loop prevention necessary? */ 1486 struct ip6_ext *ip6e = NULL; 1487 int elen; 1488 #ifdef PULLDOWN_TEST 1489 struct mbuf *ext = NULL; 1490 #endif 1491 1492 /* 1493 * if it is not an extension header, don't try to 1494 * pull it from the chain. 1495 */ 1496 switch (nxt) { 1497 case IPPROTO_DSTOPTS: 1498 case IPPROTO_ROUTING: 1499 case IPPROTO_HOPOPTS: 1500 case IPPROTO_AH: /* is it possible? */ 1501 break; 1502 default: 1503 goto loopend; 1504 } 1505 1506 #ifndef PULLDOWN_TEST 1507 if (off + sizeof(*ip6e) > m->m_len) 1508 goto loopend; 1509 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1510 if (nxt == IPPROTO_AH) 1511 elen = (ip6e->ip6e_len + 2) << 2; 1512 else 1513 elen = (ip6e->ip6e_len + 1) << 3; 1514 if (off + elen > m->m_len) 1515 goto loopend; 1516 #else 1517 ext = ip6_pullexthdr(m, off, nxt); 1518 if (ext == NULL) { 1519 IP6STAT_INC(ip6s_tooshort); 1520 return; 1521 } 1522 ip6e = mtod(ext, struct ip6_ext *); 1523 if (nxt == IPPROTO_AH) 1524 elen = (ip6e->ip6e_len + 2) << 2; 1525 else 1526 elen = (ip6e->ip6e_len + 1) << 3; 1527 if (elen != ext->m_len) { 1528 m_freem(ext); 1529 IP6STAT_INC(ip6s_tooshort); 1530 return; 1531 } 1532 #endif 1533 1534 switch (nxt) { 1535 case IPPROTO_DSTOPTS: 1536 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1537 break; 1538 1539 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1540 IS2292(in6p, 1541 IPV6_2292DSTOPTS, IPV6_DSTOPTS), 1542 IPPROTO_IPV6); 1543 if (*mp) 1544 mp = &(*mp)->m_next; 1545 break; 1546 case IPPROTO_ROUTING: 1547 if (!(in6p->inp_flags & IN6P_RTHDR)) 1548 break; 1549 1550 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1551 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR), 1552 IPPROTO_IPV6); 1553 if (*mp) 1554 mp = &(*mp)->m_next; 1555 break; 1556 case IPPROTO_HOPOPTS: 1557 case IPPROTO_AH: /* is it possible? */ 1558 break; 1559 1560 default: 1561 /* 1562 * other cases have been filtered in the above. 1563 * none will visit this case. here we supply 1564 * the code just in case (nxt overwritten or 1565 * other cases). 1566 */ 1567 #ifdef PULLDOWN_TEST 1568 m_freem(ext); 1569 #endif 1570 goto loopend; 1571 1572 } 1573 1574 /* proceed with the next header. */ 1575 off += elen; 1576 nxt = ip6e->ip6e_nxt; 1577 ip6e = NULL; 1578 #ifdef PULLDOWN_TEST 1579 m_freem(ext); 1580 ext = NULL; 1581 #endif 1582 } 1583 loopend: 1584 ; 1585 } 1586 1587 if (in6p->inp_flags2 & INP_RECVFLOWID) { 1588 uint32_t flowid, flow_type; 1589 1590 flowid = m->m_pkthdr.flowid; 1591 flow_type = M_HASHTYPE_GET(m); 1592 1593 /* 1594 * XXX should handle the failure of one or the 1595 * other - don't populate both? 1596 */ 1597 *mp = sbcreatecontrol((caddr_t) &flowid, 1598 sizeof(uint32_t), IPV6_FLOWID, IPPROTO_IPV6); 1599 if (*mp) 1600 mp = &(*mp)->m_next; 1601 *mp = sbcreatecontrol((caddr_t) &flow_type, 1602 sizeof(uint32_t), IPV6_FLOWTYPE, IPPROTO_IPV6); 1603 if (*mp) 1604 mp = &(*mp)->m_next; 1605 } 1606 1607 #ifdef RSS 1608 if (in6p->inp_flags2 & INP_RECVRSSBUCKETID) { 1609 uint32_t flowid, flow_type; 1610 uint32_t rss_bucketid; 1611 1612 flowid = m->m_pkthdr.flowid; 1613 flow_type = M_HASHTYPE_GET(m); 1614 1615 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) { 1616 *mp = sbcreatecontrol((caddr_t) &rss_bucketid, 1617 sizeof(uint32_t), IPV6_RSSBUCKETID, IPPROTO_IPV6); 1618 if (*mp) 1619 mp = &(*mp)->m_next; 1620 } 1621 } 1622 #endif 1623 1624 } 1625 #undef IS2292 1626 1627 void 1628 ip6_notify_pmtu(struct inpcb *inp, struct sockaddr_in6 *dst, u_int32_t mtu) 1629 { 1630 struct socket *so; 1631 struct mbuf *m_mtu; 1632 struct ip6_mtuinfo mtuctl; 1633 1634 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 1635 /* 1636 * Notify the error by sending IPV6_PATHMTU ancillary data if 1637 * application wanted to know the MTU value. 1638 * NOTE: we notify disconnected sockets, because some udp 1639 * applications keep sending sockets disconnected. 1640 * NOTE: our implementation doesn't notify connected sockets that has 1641 * foreign address that is different than given destination addresses 1642 * (this is permitted by RFC 3542). 1643 */ 1644 if ((inp->inp_flags & IN6P_MTU) == 0 || ( 1645 !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) && 1646 !IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &dst->sin6_addr))) 1647 return; 1648 1649 mtuctl.ip6m_mtu = mtu; 1650 mtuctl.ip6m_addr = *dst; 1651 if (sa6_recoverscope(&mtuctl.ip6m_addr)) 1652 return; 1653 1654 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), 1655 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) 1656 return; 1657 1658 so = inp->inp_socket; 1659 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu) 1660 == 0) { 1661 m_freem(m_mtu); 1662 /* XXX: should count statistics */ 1663 } else 1664 sorwakeup(so); 1665 } 1666 1667 #ifdef PULLDOWN_TEST 1668 /* 1669 * pull single extension header from mbuf chain. returns single mbuf that 1670 * contains the result, or NULL on error. 1671 */ 1672 static struct mbuf * 1673 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1674 { 1675 struct ip6_ext ip6e; 1676 size_t elen; 1677 struct mbuf *n; 1678 1679 #ifdef DIAGNOSTIC 1680 switch (nxt) { 1681 case IPPROTO_DSTOPTS: 1682 case IPPROTO_ROUTING: 1683 case IPPROTO_HOPOPTS: 1684 case IPPROTO_AH: /* is it possible? */ 1685 break; 1686 default: 1687 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1688 } 1689 #endif 1690 1691 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1692 if (nxt == IPPROTO_AH) 1693 elen = (ip6e.ip6e_len + 2) << 2; 1694 else 1695 elen = (ip6e.ip6e_len + 1) << 3; 1696 1697 if (elen > MLEN) 1698 n = m_getcl(M_NOWAIT, MT_DATA, 0); 1699 else 1700 n = m_get(M_NOWAIT, MT_DATA); 1701 if (n == NULL) 1702 return NULL; 1703 1704 m_copydata(m, off, elen, mtod(n, caddr_t)); 1705 n->m_len = elen; 1706 return n; 1707 } 1708 #endif 1709 1710 /* 1711 * Get pointer to the previous header followed by the header 1712 * currently processed. 1713 */ 1714 int 1715 ip6_get_prevhdr(const struct mbuf *m, int off) 1716 { 1717 struct ip6_ext ip6e; 1718 struct ip6_hdr *ip6; 1719 int len, nlen, nxt; 1720 1721 if (off == sizeof(struct ip6_hdr)) 1722 return (offsetof(struct ip6_hdr, ip6_nxt)); 1723 if (off < sizeof(struct ip6_hdr)) 1724 panic("%s: off < sizeof(struct ip6_hdr)", __func__); 1725 1726 ip6 = mtod(m, struct ip6_hdr *); 1727 nxt = ip6->ip6_nxt; 1728 len = sizeof(struct ip6_hdr); 1729 nlen = 0; 1730 while (len < off) { 1731 m_copydata(m, len, sizeof(ip6e), (caddr_t)&ip6e); 1732 switch (nxt) { 1733 case IPPROTO_FRAGMENT: 1734 nlen = sizeof(struct ip6_frag); 1735 break; 1736 case IPPROTO_AH: 1737 nlen = (ip6e.ip6e_len + 2) << 2; 1738 break; 1739 default: 1740 nlen = (ip6e.ip6e_len + 1) << 3; 1741 } 1742 len += nlen; 1743 nxt = ip6e.ip6e_nxt; 1744 } 1745 return (len - nlen); 1746 } 1747 1748 /* 1749 * get next header offset. m will be retained. 1750 */ 1751 int 1752 ip6_nexthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1753 { 1754 struct ip6_hdr ip6; 1755 struct ip6_ext ip6e; 1756 struct ip6_frag fh; 1757 1758 /* just in case */ 1759 if (m == NULL) 1760 panic("ip6_nexthdr: m == NULL"); 1761 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1762 return -1; 1763 1764 switch (proto) { 1765 case IPPROTO_IPV6: 1766 if (m->m_pkthdr.len < off + sizeof(ip6)) 1767 return -1; 1768 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1769 if (nxtp) 1770 *nxtp = ip6.ip6_nxt; 1771 off += sizeof(ip6); 1772 return off; 1773 1774 case IPPROTO_FRAGMENT: 1775 /* 1776 * terminate parsing if it is not the first fragment, 1777 * it does not make sense to parse through it. 1778 */ 1779 if (m->m_pkthdr.len < off + sizeof(fh)) 1780 return -1; 1781 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1782 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ 1783 if (fh.ip6f_offlg & IP6F_OFF_MASK) 1784 return -1; 1785 if (nxtp) 1786 *nxtp = fh.ip6f_nxt; 1787 off += sizeof(struct ip6_frag); 1788 return off; 1789 1790 case IPPROTO_AH: 1791 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1792 return -1; 1793 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1794 if (nxtp) 1795 *nxtp = ip6e.ip6e_nxt; 1796 off += (ip6e.ip6e_len + 2) << 2; 1797 return off; 1798 1799 case IPPROTO_HOPOPTS: 1800 case IPPROTO_ROUTING: 1801 case IPPROTO_DSTOPTS: 1802 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1803 return -1; 1804 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1805 if (nxtp) 1806 *nxtp = ip6e.ip6e_nxt; 1807 off += (ip6e.ip6e_len + 1) << 3; 1808 return off; 1809 1810 case IPPROTO_NONE: 1811 case IPPROTO_ESP: 1812 case IPPROTO_IPCOMP: 1813 /* give up */ 1814 return -1; 1815 1816 default: 1817 return -1; 1818 } 1819 1820 /* NOTREACHED */ 1821 } 1822 1823 /* 1824 * get offset for the last header in the chain. m will be kept untainted. 1825 */ 1826 int 1827 ip6_lasthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1828 { 1829 int newoff; 1830 int nxt; 1831 1832 if (!nxtp) { 1833 nxt = -1; 1834 nxtp = &nxt; 1835 } 1836 while (1) { 1837 newoff = ip6_nexthdr(m, off, proto, nxtp); 1838 if (newoff < 0) 1839 return off; 1840 else if (newoff < off) 1841 return -1; /* invalid */ 1842 else if (newoff == off) 1843 return newoff; 1844 1845 off = newoff; 1846 proto = *nxtp; 1847 } 1848 } 1849 1850 /* 1851 * System control for IP6 1852 */ 1853 1854 u_char inet6ctlerrmap[PRC_NCMDS] = { 1855 0, 0, 0, 0, 1856 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1857 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1858 EMSGSIZE, EHOSTUNREACH, 0, 0, 1859 0, 0, EHOSTUNREACH, 0, 1860 ENOPROTOOPT, ECONNREFUSED 1861 }; 1862