1 /* $FreeBSD$ */ 2 /* $KAME: ip6_input.c,v 1.95 2000/07/02 07:49:37 jinmei Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1988, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 66 */ 67 68 #include "opt_ip6fw.h" 69 #include "opt_inet.h" 70 #include "opt_inet6.h" 71 #include "opt_ipsec.h" 72 #include "opt_pfil_hooks.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/mbuf.h> 77 #include <sys/domain.h> 78 #include <sys/protosw.h> 79 #include <sys/socket.h> 80 #include <sys/socketvar.h> 81 #include <sys/errno.h> 82 #include <sys/time.h> 83 #include <sys/kernel.h> 84 #include <sys/syslog.h> 85 86 #include <net/if.h> 87 #include <net/if_types.h> 88 #include <net/if_dl.h> 89 #include <net/route.h> 90 #include <net/netisr.h> 91 #include <net/intrq.h> 92 #ifdef PFIL_HOOKS 93 #include <net/pfil.h> 94 #endif 95 96 #include <netinet/in.h> 97 #include <netinet/in_systm.h> 98 #ifdef INET 99 #include <netinet/ip.h> 100 #include <netinet/ip_icmp.h> 101 #endif /*INET*/ 102 #include <netinet/ip6.h> 103 #include <netinet6/in6_var.h> 104 #include <netinet6/ip6_var.h> 105 #include <netinet/in_pcb.h> 106 #include <netinet/icmp6.h> 107 #include <netinet6/in6_ifattach.h> 108 #include <netinet6/nd6.h> 109 #include <netinet6/in6_prefix.h> 110 111 #include <netinet6/ip6_fw.h> 112 113 #include <netinet6/ip6protosw.h> 114 115 /* we need it for NLOOP. */ 116 #include "loop.h" 117 #include "faith.h" 118 #include "gif.h" 119 120 #include <net/net_osdep.h> 121 122 extern struct domain inet6domain; 123 extern struct ip6protosw inet6sw[]; 124 125 u_char ip6_protox[IPPROTO_MAX]; 126 static int ip6qmaxlen = IFQ_MAXLEN; 127 struct in6_ifaddr *in6_ifaddr; 128 129 int ip6_forward_srcrt; /* XXX */ 130 int ip6_sourcecheck; /* XXX */ 131 int ip6_sourcecheck_interval; /* XXX */ 132 const int int6intrq_present = 1; 133 134 /* firewall hooks */ 135 ip6_fw_chk_t *ip6_fw_chk_ptr; 136 ip6_fw_ctl_t *ip6_fw_ctl_ptr; 137 int ip6_fw_enable = 1; 138 139 struct ip6stat ip6stat; 140 141 static void ip6_init2 __P((void *)); 142 143 static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *)); 144 #ifdef PULLDOWN_TEST 145 static struct mbuf *ip6_pullexthdr __P((struct mbuf *, size_t, int)); 146 #endif 147 148 /* 149 * IP6 initialization: fill in IP6 protocol switch table. 150 * All protocols not implemented in kernel go to raw IP6 protocol handler. 151 */ 152 void 153 ip6_init() 154 { 155 register struct ip6protosw *pr; 156 register int i; 157 struct timeval tv; 158 159 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 160 if (pr == 0) 161 panic("ip6_init"); 162 for (i = 0; i < IPPROTO_MAX; i++) 163 ip6_protox[i] = pr - inet6sw; 164 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 165 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 166 if (pr->pr_domain->dom_family == PF_INET6 && 167 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 168 ip6_protox[pr->pr_protocol] = pr - inet6sw; 169 ip6intrq.ifq_maxlen = ip6qmaxlen; 170 register_netisr(NETISR_IPV6, ip6intr); 171 nd6_init(); 172 frag6_init(); 173 /* 174 * in many cases, random() here does NOT return random number 175 * as initialization during bootstrap time occur in fixed order. 176 */ 177 microtime(&tv); 178 ip6_flow_seq = random() ^ tv.tv_usec; 179 } 180 181 static void 182 ip6_init2(dummy) 183 void *dummy; 184 { 185 186 /* 187 * to route local address of p2p link to loopback, 188 * assign loopback address first. 189 */ 190 in6_ifattach(&loif[0], NULL); 191 192 /* nd6_timer_init */ 193 timeout(nd6_timer, (caddr_t)0, hz); 194 /* router renumbering prefix list maintenance */ 195 timeout(in6_rr_timer, (caddr_t)0, hz); 196 } 197 198 /* cheat */ 199 /* This must be after route_init(), which is now SI_ORDER_THIRD */ 200 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL); 201 202 /* 203 * IP6 input interrupt handling. Just pass the packet to ip6_input. 204 */ 205 void 206 ip6intr() 207 { 208 int s; 209 struct mbuf *m; 210 211 for (;;) { 212 s = splimp(); 213 IF_DEQUEUE(&ip6intrq, m); 214 splx(s); 215 if (m == 0) 216 return; 217 ip6_input(m); 218 } 219 } 220 221 extern struct route_in6 ip6_forward_rt; 222 223 void 224 ip6_input(m) 225 struct mbuf *m; 226 { 227 struct ip6_hdr *ip6; 228 int off = sizeof(struct ip6_hdr), nest; 229 u_int32_t plen; 230 u_int32_t rtalert = ~0; 231 int nxt, ours = 0; 232 struct ifnet *deliverifp = NULL; 233 #ifdef PFIL_HOOKS 234 struct packet_filter_hook *pfh; 235 struct mbuf *m0; 236 int rv; 237 #endif /* PFIL_HOOKS */ 238 239 #ifdef IPSEC 240 /* 241 * should the inner packet be considered authentic? 242 * see comment in ah4_input(). 243 */ 244 if (m) { 245 m->m_flags &= ~M_AUTHIPHDR; 246 m->m_flags &= ~M_AUTHIPDGM; 247 } 248 #endif 249 250 /* 251 * mbuf statistics by kazu 252 */ 253 if (m->m_flags & M_EXT) { 254 if (m->m_next) 255 ip6stat.ip6s_mext2m++; 256 else 257 ip6stat.ip6s_mext1++; 258 } else { 259 if (m->m_next) { 260 if (m->m_flags & M_LOOP) { 261 ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/ 262 } else if (m->m_pkthdr.rcvif->if_index <= 31) 263 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 264 else 265 ip6stat.ip6s_m2m[0]++; 266 } else 267 ip6stat.ip6s_m1++; 268 } 269 270 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 271 ip6stat.ip6s_total++; 272 273 #ifndef PULLDOWN_TEST 274 /* XXX is the line really necessary? */ 275 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/); 276 #endif 277 278 if (m->m_len < sizeof(struct ip6_hdr)) { 279 struct ifnet *inifp; 280 inifp = m->m_pkthdr.rcvif; 281 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 282 ip6stat.ip6s_toosmall++; 283 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 284 return; 285 } 286 } 287 288 ip6 = mtod(m, struct ip6_hdr *); 289 290 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 291 ip6stat.ip6s_badvers++; 292 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 293 goto bad; 294 } 295 296 #ifdef PFIL_HOOKS 297 /* 298 * Run through list of hooks for input packets. If there are any 299 * filters which require that additional packets in the flow are 300 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 301 * Note that filters must _never_ set this flag, as another filter 302 * in the list may have previously cleared it. 303 */ 304 m0 = m; 305 pfh = pfil_hook_get(PFIL_IN, &inet6sw[ip6_protox[IPPROTO_IPV6]].pr_pfh); 306 for (; pfh; pfh = pfh->pfil_link.tqe_next) 307 if (pfh->pfil_func) { 308 rv = pfh->pfil_func(ip6, sizeof(*ip6), 309 m->m_pkthdr.rcvif, 0, &m0); 310 if (rv) 311 return; 312 m = m0; 313 if (m == NULL) 314 return; 315 ip6 = mtod(m, struct ip6_hdr *); 316 } 317 #endif /* PFIL_HOOKS */ 318 319 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 320 321 /* 322 * Check with the firewall... 323 */ 324 if (ip6_fw_enable && ip6_fw_chk_ptr) { 325 u_short port = 0; 326 /* If ipfw says divert, we have to just drop packet */ 327 /* use port as a dummy argument */ 328 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) { 329 m_freem(m); 330 m = NULL; 331 } 332 if (!m) 333 return; 334 } 335 336 /* 337 * Scope check 338 */ 339 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 340 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 341 ip6stat.ip6s_badscope++; 342 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 343 goto bad; 344 } 345 346 /* 347 * Don't check IPv4 mapped address here. SIIT assumes that 348 * routers would forward IPv6 native packets with IPv4 mapped 349 * address normally. 350 */ 351 #if 0 352 /* 353 * Reject packets with IPv4 compatible addresses (auto tunnel). 354 * 355 * The code forbids auto tunnel relay case in RFC1933 (the check is 356 * stronger than RFC1933). We may want to re-enable it if mech-xx 357 * is revised to forbid relaying case. 358 */ 359 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 360 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 361 ip6stat.ip6s_badscope++; 362 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 363 goto bad; 364 } 365 #endif 366 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 367 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 368 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 369 ours = 1; 370 deliverifp = m->m_pkthdr.rcvif; 371 goto hbhcheck; 372 } else { 373 ip6stat.ip6s_badscope++; 374 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 375 goto bad; 376 } 377 } 378 379 #ifndef FAKE_LOOPBACK_IF 380 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) 381 #else 382 if (1) 383 #endif 384 { 385 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 386 ip6->ip6_src.s6_addr16[1] 387 = htons(m->m_pkthdr.rcvif->if_index); 388 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 389 ip6->ip6_dst.s6_addr16[1] 390 = htons(m->m_pkthdr.rcvif->if_index); 391 } 392 393 /* 394 * XXX we need this since we do not have "goto ours" hack route 395 * for some of our ifaddrs on loopback interface. 396 * we should correct it by changing in6_ifattach to install 397 * "goto ours" hack route. 398 */ 399 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) != 0) { 400 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 401 ours = 1; 402 deliverifp = m->m_pkthdr.rcvif; 403 goto hbhcheck; 404 } 405 } 406 407 /* 408 * Multicast check 409 */ 410 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 411 struct in6_multi *in6m = 0; 412 413 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 414 /* 415 * See if we belong to the destination multicast group on the 416 * arrival interface. 417 */ 418 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 419 if (in6m) 420 ours = 1; 421 else if (!ip6_mrouter) { 422 ip6stat.ip6s_notmember++; 423 ip6stat.ip6s_cantforward++; 424 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 425 goto bad; 426 } 427 deliverifp = m->m_pkthdr.rcvif; 428 goto hbhcheck; 429 } 430 431 /* 432 * Unicast check 433 */ 434 if (ip6_forward_rt.ro_rt != NULL && 435 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) != 0 && 436 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 437 &ip6_forward_rt.ro_dst.sin6_addr)) 438 ip6stat.ip6s_forward_cachehit++; 439 else { 440 if (ip6_forward_rt.ro_rt) { 441 /* route is down or destination is different */ 442 ip6stat.ip6s_forward_cachemiss++; 443 RTFREE(ip6_forward_rt.ro_rt); 444 ip6_forward_rt.ro_rt = 0; 445 } 446 447 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 448 ip6_forward_rt.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 449 ip6_forward_rt.ro_dst.sin6_family = AF_INET6; 450 ip6_forward_rt.ro_dst.sin6_addr = ip6->ip6_dst; 451 #ifdef SCOPEDROUTING 452 ip6_forward_rt.ro_dst.sin6_scope_id = 453 in6_addr2scopeid(m->m_pkthdr.rcvif, &ip6->ip6_dst); 454 #endif 455 456 rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING); 457 } 458 459 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 460 461 /* 462 * Accept the packet if the forwarding interface to the destination 463 * according to the routing table is the loopback interface, 464 * unless the associated route has a gateway. 465 * Note that this approach causes to accept a packet if there is a 466 * route to the loopback interface for the destination of the packet. 467 * But we think it's even useful in some situations, e.g. when using 468 * a special daemon which wants to intercept the packet. 469 */ 470 if (ip6_forward_rt.ro_rt && 471 (ip6_forward_rt.ro_rt->rt_flags & 472 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 473 #if 0 474 /* 475 * The check below is redundant since the comparison of 476 * the destination and the key of the rtentry has 477 * already done through looking up the routing table. 478 */ 479 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 480 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) && 481 #endif 482 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 483 struct in6_ifaddr *ia6 = 484 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 485 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 486 m->m_flags |= M_ANYCAST6; 487 /* 488 * packets to a tentative, duplicated, or somehow invalid 489 * address must not be accepted. 490 */ 491 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 492 /* this address is ready */ 493 ours = 1; 494 deliverifp = ia6->ia_ifp; /* correct? */ 495 496 /* Count the packet in the ip address stats */ 497 ia6->ia_ifa.if_ipackets++; 498 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len; 499 500 goto hbhcheck; 501 } else { 502 /* address is not ready, so discard the packet. */ 503 log(LOG_INFO, 504 "ip6_input: packet to an unready address %s->%s", 505 ip6_sprintf(&ip6->ip6_src), 506 ip6_sprintf(&ip6->ip6_dst)); 507 508 goto bad; 509 } 510 } 511 512 /* 513 * FAITH(Firewall Aided Internet Translator) 514 */ 515 #if defined(NFAITH) && 0 < NFAITH 516 if (ip6_keepfaith) { 517 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 518 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 519 /* XXX do we need more sanity checks? */ 520 ours = 1; 521 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 522 goto hbhcheck; 523 } 524 } 525 #endif 526 527 /* 528 * Now there is no reason to process the packet if it's not our own 529 * and we're not a router. 530 */ 531 if (!ip6_forwarding) { 532 ip6stat.ip6s_cantforward++; 533 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 534 goto bad; 535 } 536 537 hbhcheck: 538 /* 539 * Process Hop-by-Hop options header if it's contained. 540 * m may be modified in ip6_hopopts_input(). 541 * If a JumboPayload option is included, plen will also be modified. 542 */ 543 plen = (u_int32_t)ntohs(ip6->ip6_plen); 544 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 545 struct ip6_hbh *hbh; 546 547 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 548 #if 0 /*touches NULL pointer*/ 549 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 550 #endif 551 return; /* m have already been freed */ 552 } 553 554 /* adjust pointer */ 555 ip6 = mtod(m, struct ip6_hdr *); 556 557 /* 558 * if the payload length field is 0 and the next header field 559 * indicates Hop-by-Hop Options header, then a Jumbo Payload 560 * option MUST be included. 561 */ 562 if (ip6->ip6_plen == 0 && plen == 0) { 563 /* 564 * Note that if a valid jumbo payload option is 565 * contained, ip6_hoptops_input() must set a valid 566 * (non-zero) payload length to the variable plen. 567 */ 568 ip6stat.ip6s_badoptions++; 569 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 570 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 571 icmp6_error(m, ICMP6_PARAM_PROB, 572 ICMP6_PARAMPROB_HEADER, 573 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 574 return; 575 } 576 #ifndef PULLDOWN_TEST 577 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 578 hbh = (struct ip6_hbh *)(ip6 + 1); 579 #else 580 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 581 sizeof(struct ip6_hbh)); 582 if (hbh == NULL) { 583 ip6stat.ip6s_tooshort++; 584 return; 585 } 586 #endif 587 nxt = hbh->ip6h_nxt; 588 589 /* 590 * accept the packet if a router alert option is included 591 * and we act as an IPv6 router. 592 */ 593 if (rtalert != ~0 && ip6_forwarding) 594 ours = 1; 595 } else 596 nxt = ip6->ip6_nxt; 597 598 /* 599 * Check that the amount of data in the buffers 600 * is as at least much as the IPv6 header would have us expect. 601 * Trim mbufs if longer than we expect. 602 * Drop packet if shorter than we expect. 603 */ 604 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 605 ip6stat.ip6s_tooshort++; 606 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 607 goto bad; 608 } 609 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 610 if (m->m_len == m->m_pkthdr.len) { 611 m->m_len = sizeof(struct ip6_hdr) + plen; 612 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 613 } else 614 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 615 } 616 617 /* 618 * Forward if desirable. 619 */ 620 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 621 /* 622 * If we are acting as a multicast router, all 623 * incoming multicast packets are passed to the 624 * kernel-level multicast forwarding function. 625 * The packet is returned (relatively) intact; if 626 * ip6_mforward() returns a non-zero value, the packet 627 * must be discarded, else it may be accepted below. 628 */ 629 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 630 ip6stat.ip6s_cantforward++; 631 m_freem(m); 632 return; 633 } 634 if (!ours) { 635 m_freem(m); 636 return; 637 } 638 } else if (!ours) { 639 ip6_forward(m, 0); 640 return; 641 } 642 643 ip6 = mtod(m, struct ip6_hdr *); 644 645 /* 646 * Malicious party may be able to use IPv4 mapped addr to confuse 647 * tcp/udp stack and bypass security checks (act as if it was from 648 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 649 * 650 * For SIIT end node behavior, you may want to disable the check. 651 * However, you will become vulnerable to attacks using IPv4 mapped 652 * source. 653 */ 654 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 655 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 656 ip6stat.ip6s_badscope++; 657 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 658 goto bad; 659 } 660 661 /* 662 * Tell launch routine the next header 663 */ 664 ip6stat.ip6s_delivered++; 665 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 666 nest = 0; 667 while (nxt != IPPROTO_DONE) { 668 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 669 ip6stat.ip6s_toomanyhdr++; 670 goto bad; 671 } 672 673 /* 674 * protection against faulty packet - there should be 675 * more sanity checks in header chain processing. 676 */ 677 if (m->m_pkthdr.len < off) { 678 ip6stat.ip6s_tooshort++; 679 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 680 goto bad; 681 } 682 683 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 684 } 685 return; 686 bad: 687 m_freem(m); 688 } 689 690 /* 691 * Hop-by-Hop options header processing. If a valid jumbo payload option is 692 * included, the real payload length will be stored in plenp. 693 */ 694 static int 695 ip6_hopopts_input(plenp, rtalertp, mp, offp) 696 u_int32_t *plenp; 697 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 698 struct mbuf **mp; 699 int *offp; 700 { 701 register struct mbuf *m = *mp; 702 int off = *offp, hbhlen; 703 struct ip6_hbh *hbh; 704 u_int8_t *opt; 705 706 /* validation of the length of the header */ 707 #ifndef PULLDOWN_TEST 708 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 709 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 710 hbhlen = (hbh->ip6h_len + 1) << 3; 711 712 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 713 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 714 #else 715 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 716 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 717 if (hbh == NULL) { 718 ip6stat.ip6s_tooshort++; 719 return -1; 720 } 721 hbhlen = (hbh->ip6h_len + 1) << 3; 722 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 723 hbhlen); 724 if (hbh == NULL) { 725 ip6stat.ip6s_tooshort++; 726 return -1; 727 } 728 #endif 729 off += hbhlen; 730 hbhlen -= sizeof(struct ip6_hbh); 731 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 732 733 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 734 hbhlen, rtalertp, plenp) < 0) 735 return(-1); 736 737 *offp = off; 738 *mp = m; 739 return(0); 740 } 741 742 /* 743 * Search header for all Hop-by-hop options and process each option. 744 * This function is separate from ip6_hopopts_input() in order to 745 * handle a case where the sending node itself process its hop-by-hop 746 * options header. In such a case, the function is called from ip6_output(). 747 */ 748 int 749 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 750 struct mbuf *m; 751 u_int8_t *opthead; 752 int hbhlen; 753 u_int32_t *rtalertp; 754 u_int32_t *plenp; 755 { 756 struct ip6_hdr *ip6; 757 int optlen = 0; 758 u_int8_t *opt = opthead; 759 u_int16_t rtalert_val; 760 u_int32_t jumboplen; 761 762 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 763 switch(*opt) { 764 case IP6OPT_PAD1: 765 optlen = 1; 766 break; 767 case IP6OPT_PADN: 768 if (hbhlen < IP6OPT_MINLEN) { 769 ip6stat.ip6s_toosmall++; 770 goto bad; 771 } 772 optlen = *(opt + 1) + 2; 773 break; 774 case IP6OPT_RTALERT: 775 /* XXX may need check for alignment */ 776 if (hbhlen < IP6OPT_RTALERT_LEN) { 777 ip6stat.ip6s_toosmall++; 778 goto bad; 779 } 780 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) 781 /* XXX: should we discard the packet? */ 782 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 783 *(opt + 1)); 784 optlen = IP6OPT_RTALERT_LEN; 785 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 786 *rtalertp = ntohs(rtalert_val); 787 break; 788 case IP6OPT_JUMBO: 789 /* XXX may need check for alignment */ 790 if (hbhlen < IP6OPT_JUMBO_LEN) { 791 ip6stat.ip6s_toosmall++; 792 goto bad; 793 } 794 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) 795 /* XXX: should we discard the packet? */ 796 log(LOG_ERR, "length of jumbopayload opt " 797 "is inconsistent(%d)", 798 *(opt + 1)); 799 optlen = IP6OPT_JUMBO_LEN; 800 801 /* 802 * IPv6 packets that have non 0 payload length 803 * must not contain a jumbo paylod option. 804 */ 805 ip6 = mtod(m, struct ip6_hdr *); 806 if (ip6->ip6_plen) { 807 ip6stat.ip6s_badoptions++; 808 icmp6_error(m, ICMP6_PARAM_PROB, 809 ICMP6_PARAMPROB_HEADER, 810 sizeof(struct ip6_hdr) + 811 sizeof(struct ip6_hbh) + 812 opt - opthead); 813 return(-1); 814 } 815 816 /* 817 * We may see jumbolen in unaligned location, so 818 * we'd need to perform bcopy(). 819 */ 820 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 821 jumboplen = (u_int32_t)htonl(jumboplen); 822 823 #if 1 824 /* 825 * if there are multiple jumbo payload options, 826 * *plenp will be non-zero and the packet will be 827 * rejected. 828 * the behavior may need some debate in ipngwg - 829 * multiple options does not make sense, however, 830 * there's no explicit mention in specification. 831 */ 832 if (*plenp != 0) { 833 ip6stat.ip6s_badoptions++; 834 icmp6_error(m, ICMP6_PARAM_PROB, 835 ICMP6_PARAMPROB_HEADER, 836 sizeof(struct ip6_hdr) + 837 sizeof(struct ip6_hbh) + 838 opt + 2 - opthead); 839 return(-1); 840 } 841 #endif 842 843 /* 844 * jumbo payload length must be larger than 65535. 845 */ 846 if (jumboplen <= IPV6_MAXPACKET) { 847 ip6stat.ip6s_badoptions++; 848 icmp6_error(m, ICMP6_PARAM_PROB, 849 ICMP6_PARAMPROB_HEADER, 850 sizeof(struct ip6_hdr) + 851 sizeof(struct ip6_hbh) + 852 opt + 2 - opthead); 853 return(-1); 854 } 855 *plenp = jumboplen; 856 857 break; 858 default: /* unknown option */ 859 if (hbhlen < IP6OPT_MINLEN) { 860 ip6stat.ip6s_toosmall++; 861 goto bad; 862 } 863 if ((optlen = ip6_unknown_opt(opt, m, 864 sizeof(struct ip6_hdr) + 865 sizeof(struct ip6_hbh) + 866 opt - opthead)) == -1) 867 return(-1); 868 optlen += 2; 869 break; 870 } 871 } 872 873 return(0); 874 875 bad: 876 m_freem(m); 877 return(-1); 878 } 879 880 /* 881 * Unknown option processing. 882 * The third argument `off' is the offset from the IPv6 header to the option, 883 * which is necessary if the IPv6 header the and option header and IPv6 header 884 * is not continuous in order to return an ICMPv6 error. 885 */ 886 int 887 ip6_unknown_opt(optp, m, off) 888 u_int8_t *optp; 889 struct mbuf *m; 890 int off; 891 { 892 struct ip6_hdr *ip6; 893 894 switch(IP6OPT_TYPE(*optp)) { 895 case IP6OPT_TYPE_SKIP: /* ignore the option */ 896 return((int)*(optp + 1)); 897 case IP6OPT_TYPE_DISCARD: /* silently discard */ 898 m_freem(m); 899 return(-1); 900 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 901 ip6stat.ip6s_badoptions++; 902 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 903 return(-1); 904 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 905 ip6stat.ip6s_badoptions++; 906 ip6 = mtod(m, struct ip6_hdr *); 907 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 908 (m->m_flags & (M_BCAST|M_MCAST))) 909 m_freem(m); 910 else 911 icmp6_error(m, ICMP6_PARAM_PROB, 912 ICMP6_PARAMPROB_OPTION, off); 913 return(-1); 914 } 915 916 m_freem(m); /* XXX: NOTREACHED */ 917 return(-1); 918 } 919 920 /* 921 * Create the "control" list for this pcb. 922 * 923 * The routine will be called from upper layer handlers like tcp6_input(). 924 * Thus the routine assumes that the caller (tcp6_input) have already 925 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 926 * very first mbuf on the mbuf chain. 927 * We may want to add some infinite loop prevention or sanity checks for safety. 928 * (This applies only when you are using KAME mbuf chain restriction, i.e. 929 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 930 */ 931 void 932 ip6_savecontrol(in6p, mp, ip6, m) 933 register struct in6pcb *in6p; 934 register struct mbuf **mp; 935 register struct ip6_hdr *ip6; 936 register struct mbuf *m; 937 { 938 struct proc *p = curproc; /* XXX */ 939 int privileged; 940 941 privileged = 0; 942 if (p && !suser(p)) 943 privileged++; 944 945 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 946 struct timeval tv; 947 948 microtime(&tv); 949 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 950 SCM_TIMESTAMP, SOL_SOCKET); 951 if (*mp) 952 mp = &(*mp)->m_next; 953 } 954 955 #ifdef noyet 956 /* options were tossed above */ 957 if (in6p->in6p_flags & IN6P_RECVOPTS) 958 /* broken */ 959 /* ip6_srcroute doesn't do what we want here, need to fix */ 960 if (in6p->in6p_flags & IPV6P_RECVRETOPTS) 961 /* broken */ 962 #endif 963 964 /* RFC 2292 sec. 5 */ 965 if (in6p->in6p_flags & IN6P_PKTINFO) { 966 struct in6_pktinfo pi6; 967 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 968 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 969 pi6.ipi6_addr.s6_addr16[1] = 0; 970 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 971 ? m->m_pkthdr.rcvif->if_index 972 : 0; 973 *mp = sbcreatecontrol((caddr_t) &pi6, 974 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 975 IPPROTO_IPV6); 976 if (*mp) 977 mp = &(*mp)->m_next; 978 } 979 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 980 int hlim = ip6->ip6_hlim & 0xff; 981 *mp = sbcreatecontrol((caddr_t) &hlim, 982 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 983 if (*mp) 984 mp = &(*mp)->m_next; 985 } 986 /* IN6P_NEXTHOP - for outgoing packet only */ 987 988 /* 989 * IPV6_HOPOPTS socket option. We require super-user privilege 990 * for the option, but it might be too strict, since there might 991 * be some hop-by-hop options which can be returned to normal user. 992 * See RFC 2292 section 6. 993 */ 994 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 995 /* 996 * Check if a hop-by-hop options header is contatined in the 997 * received packet, and if so, store the options as ancillary 998 * data. Note that a hop-by-hop options header must be 999 * just after the IPv6 header, which fact is assured through 1000 * the IPv6 input processing. 1001 */ 1002 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1003 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1004 struct ip6_hbh *hbh; 1005 int hbhlen; 1006 1007 #ifndef PULLDOWN_TEST 1008 hbh = (struct ip6_hbh *)(ip6 + 1); 1009 hbhlen = (hbh->ip6h_len + 1) << 3; 1010 #else 1011 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1012 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1013 if (hbh == NULL) { 1014 ip6stat.ip6s_tooshort++; 1015 return; 1016 } 1017 hbhlen = (hbh->ip6h_len + 1) << 3; 1018 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1019 sizeof(struct ip6_hdr), hbhlen); 1020 if (hbh == NULL) { 1021 ip6stat.ip6s_tooshort++; 1022 return; 1023 } 1024 #endif 1025 1026 /* 1027 * XXX: We copy whole the header even if a jumbo 1028 * payload option is included, which option is to 1029 * be removed before returning in the RFC 2292. 1030 * But it's too painful operation... 1031 */ 1032 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1033 IPV6_HOPOPTS, IPPROTO_IPV6); 1034 if (*mp) 1035 mp = &(*mp)->m_next; 1036 } 1037 } 1038 1039 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1040 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 1041 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1042 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 1043 1044 /* 1045 * Search for destination options headers or routing 1046 * header(s) through the header chain, and stores each 1047 * header as ancillary data. 1048 * Note that the order of the headers remains in 1049 * the chain of ancillary data. 1050 */ 1051 while(1) { /* is explicit loop prevention necessary? */ 1052 struct ip6_ext *ip6e; 1053 int elen; 1054 1055 #ifndef PULLDOWN_TEST 1056 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1057 if (nxt == IPPROTO_AH) 1058 elen = (ip6e->ip6e_len + 2) << 2; 1059 else 1060 elen = (ip6e->ip6e_len + 1) << 3; 1061 #else 1062 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, 1063 sizeof(struct ip6_ext)); 1064 if (ip6e == NULL) { 1065 ip6stat.ip6s_tooshort++; 1066 return; 1067 } 1068 if (nxt == IPPROTO_AH) 1069 elen = (ip6e->ip6e_len + 2) << 2; 1070 else 1071 elen = (ip6e->ip6e_len + 1) << 3; 1072 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, elen); 1073 if (ip6e == NULL) { 1074 ip6stat.ip6s_tooshort++; 1075 return; 1076 } 1077 #endif 1078 1079 switch(nxt) { 1080 case IPPROTO_DSTOPTS: 1081 if (!in6p->in6p_flags & IN6P_DSTOPTS) 1082 break; 1083 1084 /* 1085 * We also require super-user privilege for 1086 * the option. 1087 * See the comments on IN6_HOPOPTS. 1088 */ 1089 if (!privileged) 1090 break; 1091 1092 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1093 IPV6_DSTOPTS, 1094 IPPROTO_IPV6); 1095 if (*mp) 1096 mp = &(*mp)->m_next; 1097 break; 1098 1099 case IPPROTO_ROUTING: 1100 if (!in6p->in6p_flags & IN6P_RTHDR) 1101 break; 1102 1103 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1104 IPV6_RTHDR, 1105 IPPROTO_IPV6); 1106 if (*mp) 1107 mp = &(*mp)->m_next; 1108 break; 1109 1110 case IPPROTO_UDP: 1111 case IPPROTO_TCP: 1112 case IPPROTO_ICMPV6: 1113 default: 1114 /* 1115 * stop search if we encounter an upper 1116 * layer protocol headers. 1117 */ 1118 goto loopend; 1119 1120 case IPPROTO_HOPOPTS: 1121 case IPPROTO_AH: /* is it possible? */ 1122 break; 1123 } 1124 1125 /* proceed with the next header. */ 1126 off += elen; 1127 nxt = ip6e->ip6e_nxt; 1128 } 1129 loopend: 1130 } 1131 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1132 /* to be done */ 1133 } 1134 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 1135 /* to be done */ 1136 } 1137 /* IN6P_RTHDR - to be done */ 1138 1139 } 1140 1141 /* 1142 * Get pointer to the previous header followed by the header 1143 * currently processed. 1144 * XXX: This function supposes that 1145 * M includes all headers, 1146 * the next header field and the header length field of each header 1147 * are valid, and 1148 * the sum of each header length equals to OFF. 1149 * Because of these assumptions, this function must be called very 1150 * carefully. Moreover, it will not be used in the near future when 1151 * we develop `neater' mechanism to process extension headers. 1152 */ 1153 char * 1154 ip6_get_prevhdr(m, off) 1155 struct mbuf *m; 1156 int off; 1157 { 1158 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1159 1160 if (off == sizeof(struct ip6_hdr)) 1161 return(&ip6->ip6_nxt); 1162 else { 1163 int len, nxt; 1164 struct ip6_ext *ip6e = NULL; 1165 1166 nxt = ip6->ip6_nxt; 1167 len = sizeof(struct ip6_hdr); 1168 while (len < off) { 1169 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1170 1171 switch(nxt) { 1172 case IPPROTO_FRAGMENT: 1173 len += sizeof(struct ip6_frag); 1174 break; 1175 case IPPROTO_AH: 1176 len += (ip6e->ip6e_len + 2) << 2; 1177 break; 1178 default: 1179 len += (ip6e->ip6e_len + 1) << 3; 1180 break; 1181 } 1182 nxt = ip6e->ip6e_nxt; 1183 } 1184 if (ip6e) 1185 return(&ip6e->ip6e_nxt); 1186 else 1187 return NULL; 1188 } 1189 } 1190 1191 /* 1192 * get next header offset. m will be retained. 1193 */ 1194 int 1195 ip6_nexthdr(m, off, proto, nxtp) 1196 struct mbuf *m; 1197 int off; 1198 int proto; 1199 int *nxtp; 1200 { 1201 struct ip6_hdr ip6; 1202 struct ip6_ext ip6e; 1203 struct ip6_frag fh; 1204 1205 /* just in case */ 1206 if (m == NULL) 1207 panic("ip6_nexthdr: m == NULL"); 1208 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1209 return -1; 1210 1211 switch (proto) { 1212 case IPPROTO_IPV6: 1213 if (m->m_pkthdr.len < off + sizeof(ip6)) 1214 return -1; 1215 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1216 if (nxtp) 1217 *nxtp = ip6.ip6_nxt; 1218 off += sizeof(ip6); 1219 return off; 1220 1221 case IPPROTO_FRAGMENT: 1222 /* 1223 * terminate parsing if it is not the first fragment, 1224 * it does not make sense to parse through it. 1225 */ 1226 if (m->m_pkthdr.len < off + sizeof(fh)) 1227 return -1; 1228 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1229 if ((ntohs(fh.ip6f_offlg) & IP6F_OFF_MASK) != 0) 1230 return -1; 1231 if (nxtp) 1232 *nxtp = fh.ip6f_nxt; 1233 off += sizeof(struct ip6_frag); 1234 return off; 1235 1236 case IPPROTO_AH: 1237 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1238 return -1; 1239 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1240 if (nxtp) 1241 *nxtp = ip6e.ip6e_nxt; 1242 off += (ip6e.ip6e_len + 2) << 2; 1243 return off; 1244 1245 case IPPROTO_HOPOPTS: 1246 case IPPROTO_ROUTING: 1247 case IPPROTO_DSTOPTS: 1248 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1249 return -1; 1250 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1251 if (nxtp) 1252 *nxtp = ip6e.ip6e_nxt; 1253 off += (ip6e.ip6e_len + 1) << 3; 1254 return off; 1255 1256 case IPPROTO_NONE: 1257 case IPPROTO_ESP: 1258 case IPPROTO_IPCOMP: 1259 /* give up */ 1260 return -1; 1261 1262 default: 1263 return -1; 1264 } 1265 1266 return -1; 1267 } 1268 1269 /* 1270 * get offset for the last header in the chain. m will be kept untainted. 1271 */ 1272 int 1273 ip6_lasthdr(m, off, proto, nxtp) 1274 struct mbuf *m; 1275 int off; 1276 int proto; 1277 int *nxtp; 1278 { 1279 int newoff; 1280 int nxt; 1281 1282 if (!nxtp) { 1283 nxt = -1; 1284 nxtp = &nxt; 1285 } 1286 while (1) { 1287 newoff = ip6_nexthdr(m, off, proto, nxtp); 1288 if (newoff < 0) 1289 return off; 1290 else if (newoff < off) 1291 return -1; /* invalid */ 1292 else if (newoff == off) 1293 return newoff; 1294 1295 off = newoff; 1296 proto = *nxtp; 1297 } 1298 } 1299 1300 /* 1301 * System control for IP6 1302 */ 1303 1304 u_char inet6ctlerrmap[PRC_NCMDS] = { 1305 0, 0, 0, 0, 1306 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1307 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1308 EMSGSIZE, EHOSTUNREACH, 0, 0, 1309 0, 0, 0, 0, 1310 ENOPROTOOPT 1311 }; 1312