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 #include <sys/proc.h> 86 87 #include <net/if.h> 88 #include <net/if_types.h> 89 #include <net/if_dl.h> 90 #include <net/route.h> 91 #include <net/netisr.h> 92 #include <net/intrq.h> 93 #ifdef PFIL_HOOKS 94 #include <net/pfil.h> 95 #endif 96 97 #include <netinet/in.h> 98 #include <netinet/in_systm.h> 99 #ifdef INET 100 #include <netinet/ip.h> 101 #include <netinet/ip_icmp.h> 102 #endif /*INET*/ 103 #include <netinet/ip6.h> 104 #include <netinet6/in6_var.h> 105 #include <netinet6/ip6_var.h> 106 #include <netinet/in_pcb.h> 107 #include <netinet/icmp6.h> 108 #include <netinet6/in6_ifattach.h> 109 #include <netinet6/nd6.h> 110 #include <netinet6/in6_prefix.h> 111 112 #ifdef IPV6FIREWALL 113 #include <netinet6/ip6_fw.h> 114 #endif 115 116 #include <netinet6/ip6protosw.h> 117 118 /* we need it for NLOOP. */ 119 #include "loop.h" 120 #include "faith.h" 121 #include "gif.h" 122 123 #include <net/net_osdep.h> 124 125 extern struct domain inet6domain; 126 extern struct ip6protosw inet6sw[]; 127 128 u_char ip6_protox[IPPROTO_MAX]; 129 static int ip6qmaxlen = IFQ_MAXLEN; 130 struct in6_ifaddr *in6_ifaddr; 131 132 int ip6_forward_srcrt; /* XXX */ 133 int ip6_sourcecheck; /* XXX */ 134 int ip6_sourcecheck_interval; /* XXX */ 135 const int int6intrq_present = 1; 136 137 #ifdef IPV6FIREWALL 138 /* firewall hooks */ 139 ip6_fw_chk_t *ip6_fw_chk_ptr; 140 ip6_fw_ctl_t *ip6_fw_ctl_ptr; 141 #endif 142 143 struct ip6stat ip6stat; 144 145 static void ip6_init2 __P((void *)); 146 147 static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *)); 148 #ifdef PULLDOWN_TEST 149 static struct mbuf *ip6_pullexthdr __P((struct mbuf *, size_t, int)); 150 #endif 151 152 /* 153 * IP6 initialization: fill in IP6 protocol switch table. 154 * All protocols not implemented in kernel go to raw IP6 protocol handler. 155 */ 156 void 157 ip6_init() 158 { 159 register struct ip6protosw *pr; 160 register int i; 161 struct timeval tv; 162 163 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 164 if (pr == 0) 165 panic("ip6_init"); 166 for (i = 0; i < IPPROTO_MAX; i++) 167 ip6_protox[i] = pr - inet6sw; 168 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 169 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 170 if (pr->pr_domain->dom_family == PF_INET6 && 171 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 172 ip6_protox[pr->pr_protocol] = pr - inet6sw; 173 ip6intrq.ifq_maxlen = ip6qmaxlen; 174 register_netisr(NETISR_IPV6, ip6intr); 175 nd6_init(); 176 frag6_init(); 177 #ifdef IPV6FIREWALL 178 ip6_fw_init(); 179 #endif 180 /* 181 * in many cases, random() here does NOT return random number 182 * as initialization during bootstrap time occur in fixed order. 183 */ 184 microtime(&tv); 185 ip6_flow_seq = random() ^ tv.tv_usec; 186 } 187 188 static void 189 ip6_init2(dummy) 190 void *dummy; 191 { 192 193 /* 194 * to route local address of p2p link to loopback, 195 * assign loopback address first. 196 */ 197 in6_ifattach(&loif[0], NULL); 198 199 /* nd6_timer_init */ 200 timeout(nd6_timer, (caddr_t)0, hz); 201 /* router renumbering prefix list maintenance */ 202 timeout(in6_rr_timer, (caddr_t)0, hz); 203 } 204 205 /* cheat */ 206 /* This must be after route_init(), which is now SI_ORDER_THIRD */ 207 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL); 208 209 /* 210 * IP6 input interrupt handling. Just pass the packet to ip6_input. 211 */ 212 void 213 ip6intr() 214 { 215 int s; 216 struct mbuf *m; 217 218 for (;;) { 219 s = splimp(); 220 IF_DEQUEUE(&ip6intrq, m); 221 splx(s); 222 if (m == 0) 223 return; 224 ip6_input(m); 225 } 226 } 227 228 extern struct route_in6 ip6_forward_rt; 229 230 void 231 ip6_input(m) 232 struct mbuf *m; 233 { 234 struct ip6_hdr *ip6; 235 int off = sizeof(struct ip6_hdr), nest; 236 u_int32_t plen; 237 u_int32_t rtalert = ~0; 238 int nxt, ours = 0; 239 struct ifnet *deliverifp = NULL; 240 #ifdef PFIL_HOOKS 241 struct packet_filter_hook *pfh; 242 struct mbuf *m0; 243 int rv; 244 #endif /* PFIL_HOOKS */ 245 246 #ifdef IPSEC 247 /* 248 * should the inner packet be considered authentic? 249 * see comment in ah4_input(). 250 */ 251 if (m) { 252 m->m_flags &= ~M_AUTHIPHDR; 253 m->m_flags &= ~M_AUTHIPDGM; 254 } 255 #endif 256 257 /* 258 * mbuf statistics by kazu 259 */ 260 if (m->m_flags & M_EXT) { 261 if (m->m_next) 262 ip6stat.ip6s_mext2m++; 263 else 264 ip6stat.ip6s_mext1++; 265 } else { 266 if (m->m_next) { 267 if (m->m_flags & M_LOOP) { 268 ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/ 269 } else if (m->m_pkthdr.rcvif->if_index <= 31) 270 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 271 else 272 ip6stat.ip6s_m2m[0]++; 273 } else 274 ip6stat.ip6s_m1++; 275 } 276 277 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 278 ip6stat.ip6s_total++; 279 280 #ifndef PULLDOWN_TEST 281 /* XXX is the line really necessary? */ 282 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/); 283 #endif 284 285 if (m->m_len < sizeof(struct ip6_hdr)) { 286 struct ifnet *inifp; 287 inifp = m->m_pkthdr.rcvif; 288 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 289 ip6stat.ip6s_toosmall++; 290 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 291 return; 292 } 293 } 294 295 ip6 = mtod(m, struct ip6_hdr *); 296 297 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 298 ip6stat.ip6s_badvers++; 299 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 300 goto bad; 301 } 302 303 #ifdef PFIL_HOOKS 304 /* 305 * Run through list of hooks for input packets. If there are any 306 * filters which require that additional packets in the flow are 307 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 308 * Note that filters must _never_ set this flag, as another filter 309 * in the list may have previously cleared it. 310 */ 311 m0 = m; 312 pfh = pfil_hook_get(PFIL_IN, &inet6sw[ip6_protox[IPPROTO_IPV6]].pr_pfh); 313 for (; pfh; pfh = pfh->pfil_link.tqe_next) 314 if (pfh->pfil_func) { 315 rv = pfh->pfil_func(ip6, sizeof(*ip6), 316 m->m_pkthdr.rcvif, 0, &m0); 317 if (rv) 318 return; 319 m = m0; 320 if (m == NULL) 321 return; 322 ip6 = mtod(m, struct ip6_hdr *); 323 } 324 #endif /* PFIL_HOOKS */ 325 326 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 327 328 #ifdef IPV6FIREWALL 329 /* 330 * Check with the firewall... 331 */ 332 if (ip6_fw_chk_ptr) { 333 u_short port = 0; 334 /* If ipfw says divert, we have to just drop packet */ 335 /* use port as a dummy argument */ 336 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) { 337 m_freem(m); 338 m = NULL; 339 } 340 if (!m) 341 return; 342 } 343 #endif 344 345 /* 346 * Scope check 347 */ 348 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 349 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 350 ip6stat.ip6s_badscope++; 351 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 352 goto bad; 353 } 354 355 /* 356 * Don't check IPv4 mapped address here. SIIT assumes that 357 * routers would forward IPv6 native packets with IPv4 mapped 358 * address normally. 359 */ 360 #if 0 361 /* 362 * Reject packets with IPv4 compatible addresses (auto tunnel). 363 * 364 * The code forbids auto tunnel relay case in RFC1933 (the check is 365 * stronger than RFC1933). We may want to re-enable it if mech-xx 366 * is revised to forbid relaying case. 367 */ 368 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 369 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 370 ip6stat.ip6s_badscope++; 371 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 372 goto bad; 373 } 374 #endif 375 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 376 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 377 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 378 ours = 1; 379 deliverifp = m->m_pkthdr.rcvif; 380 goto hbhcheck; 381 } else { 382 ip6stat.ip6s_badscope++; 383 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 384 goto bad; 385 } 386 } 387 388 #ifndef FAKE_LOOPBACK_IF 389 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) 390 #else 391 if (1) 392 #endif 393 { 394 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 395 ip6->ip6_src.s6_addr16[1] 396 = htons(m->m_pkthdr.rcvif->if_index); 397 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 398 ip6->ip6_dst.s6_addr16[1] 399 = htons(m->m_pkthdr.rcvif->if_index); 400 } 401 402 /* 403 * XXX we need this since we do not have "goto ours" hack route 404 * for some of our ifaddrs on loopback interface. 405 * we should correct it by changing in6_ifattach to install 406 * "goto ours" hack route. 407 */ 408 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) != 0) { 409 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 410 ours = 1; 411 deliverifp = m->m_pkthdr.rcvif; 412 goto hbhcheck; 413 } 414 } 415 416 /* 417 * Multicast check 418 */ 419 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 420 struct in6_multi *in6m = 0; 421 422 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 423 /* 424 * See if we belong to the destination multicast group on the 425 * arrival interface. 426 */ 427 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 428 if (in6m) 429 ours = 1; 430 else if (!ip6_mrouter) { 431 ip6stat.ip6s_notmember++; 432 ip6stat.ip6s_cantforward++; 433 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 434 goto bad; 435 } 436 deliverifp = m->m_pkthdr.rcvif; 437 goto hbhcheck; 438 } 439 440 /* 441 * Unicast check 442 */ 443 if (ip6_forward_rt.ro_rt != NULL && 444 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) != 0 && 445 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 446 &ip6_forward_rt.ro_dst.sin6_addr)) 447 ip6stat.ip6s_forward_cachehit++; 448 else { 449 if (ip6_forward_rt.ro_rt) { 450 /* route is down or destination is different */ 451 ip6stat.ip6s_forward_cachemiss++; 452 RTFREE(ip6_forward_rt.ro_rt); 453 ip6_forward_rt.ro_rt = 0; 454 } 455 456 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 457 ip6_forward_rt.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 458 ip6_forward_rt.ro_dst.sin6_family = AF_INET6; 459 ip6_forward_rt.ro_dst.sin6_addr = ip6->ip6_dst; 460 #ifdef SCOPEDROUTING 461 ip6_forward_rt.ro_dst.sin6_scope_id = 462 in6_addr2scopeid(m->m_pkthdr.rcvif, &ip6->ip6_dst); 463 #endif 464 465 rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING); 466 } 467 468 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 469 470 /* 471 * Accept the packet if the forwarding interface to the destination 472 * according to the routing table is the loopback interface, 473 * unless the associated route has a gateway. 474 * Note that this approach causes to accept a packet if there is a 475 * route to the loopback interface for the destination of the packet. 476 * But we think it's even useful in some situations, e.g. when using 477 * a special daemon which wants to intercept the packet. 478 */ 479 if (ip6_forward_rt.ro_rt && 480 (ip6_forward_rt.ro_rt->rt_flags & 481 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 482 #if 0 483 /* 484 * The check below is redundant since the comparison of 485 * the destination and the key of the rtentry has 486 * already done through looking up the routing table. 487 */ 488 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 489 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) && 490 #endif 491 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 492 struct in6_ifaddr *ia6 = 493 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 494 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 495 m->m_flags |= M_ANYCAST6; 496 /* 497 * packets to a tentative, duplicated, or somehow invalid 498 * address must not be accepted. 499 */ 500 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 501 /* this address is ready */ 502 ours = 1; 503 deliverifp = ia6->ia_ifp; /* correct? */ 504 goto hbhcheck; 505 } else { 506 /* address is not ready, so discard the packet. */ 507 log(LOG_INFO, 508 "ip6_input: packet to an unready address %s->%s", 509 ip6_sprintf(&ip6->ip6_src), 510 ip6_sprintf(&ip6->ip6_dst)); 511 512 goto bad; 513 } 514 } 515 516 /* 517 * FAITH(Firewall Aided Internet Translator) 518 */ 519 #if defined(NFAITH) && 0 < NFAITH 520 if (ip6_keepfaith) { 521 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 522 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 523 /* XXX do we need more sanity checks? */ 524 ours = 1; 525 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 526 goto hbhcheck; 527 } 528 } 529 #endif 530 531 /* 532 * Now there is no reason to process the packet if it's not our own 533 * and we're not a router. 534 */ 535 if (!ip6_forwarding) { 536 ip6stat.ip6s_cantforward++; 537 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 538 goto bad; 539 } 540 541 hbhcheck: 542 /* 543 * Process Hop-by-Hop options header if it's contained. 544 * m may be modified in ip6_hopopts_input(). 545 * If a JumboPayload option is included, plen will also be modified. 546 */ 547 plen = (u_int32_t)ntohs(ip6->ip6_plen); 548 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 549 struct ip6_hbh *hbh; 550 551 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 552 #if 0 /*touches NULL pointer*/ 553 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 554 #endif 555 return; /* m have already been freed */ 556 } 557 558 /* adjust pointer */ 559 ip6 = mtod(m, struct ip6_hdr *); 560 561 /* 562 * if the payload length field is 0 and the next header field 563 * indicates Hop-by-Hop Options header, then a Jumbo Payload 564 * option MUST be included. 565 */ 566 if (ip6->ip6_plen == 0 && plen == 0) { 567 /* 568 * Note that if a valid jumbo payload option is 569 * contained, ip6_hoptops_input() must set a valid 570 * (non-zero) payload length to the variable plen. 571 */ 572 ip6stat.ip6s_badoptions++; 573 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 574 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 575 icmp6_error(m, ICMP6_PARAM_PROB, 576 ICMP6_PARAMPROB_HEADER, 577 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 578 return; 579 } 580 #ifndef PULLDOWN_TEST 581 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 582 hbh = (struct ip6_hbh *)(ip6 + 1); 583 #else 584 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 585 sizeof(struct ip6_hbh)); 586 if (hbh == NULL) { 587 ip6stat.ip6s_tooshort++; 588 return; 589 } 590 #endif 591 nxt = hbh->ip6h_nxt; 592 593 /* 594 * accept the packet if a router alert option is included 595 * and we act as an IPv6 router. 596 */ 597 if (rtalert != ~0 && ip6_forwarding) 598 ours = 1; 599 } else 600 nxt = ip6->ip6_nxt; 601 602 /* 603 * Check that the amount of data in the buffers 604 * is as at least much as the IPv6 header would have us expect. 605 * Trim mbufs if longer than we expect. 606 * Drop packet if shorter than we expect. 607 */ 608 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 609 ip6stat.ip6s_tooshort++; 610 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 611 goto bad; 612 } 613 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 614 if (m->m_len == m->m_pkthdr.len) { 615 m->m_len = sizeof(struct ip6_hdr) + plen; 616 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 617 } else 618 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 619 } 620 621 /* 622 * Forward if desirable. 623 */ 624 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 625 /* 626 * If we are acting as a multicast router, all 627 * incoming multicast packets are passed to the 628 * kernel-level multicast forwarding function. 629 * The packet is returned (relatively) intact; if 630 * ip6_mforward() returns a non-zero value, the packet 631 * must be discarded, else it may be accepted below. 632 */ 633 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 634 ip6stat.ip6s_cantforward++; 635 m_freem(m); 636 return; 637 } 638 if (!ours) { 639 m_freem(m); 640 return; 641 } 642 } else if (!ours) { 643 ip6_forward(m, 0); 644 return; 645 } 646 647 ip6 = mtod(m, struct ip6_hdr *); 648 649 /* 650 * Malicious party may be able to use IPv4 mapped addr to confuse 651 * tcp/udp stack and bypass security checks (act as if it was from 652 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 653 * 654 * For SIIT end node behavior, you may want to disable the check. 655 * However, you will become vulnerable to attacks using IPv4 mapped 656 * source. 657 */ 658 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 659 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 660 ip6stat.ip6s_badscope++; 661 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 662 goto bad; 663 } 664 665 /* 666 * Tell launch routine the next header 667 */ 668 ip6stat.ip6s_delivered++; 669 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 670 nest = 0; 671 while (nxt != IPPROTO_DONE) { 672 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 673 ip6stat.ip6s_toomanyhdr++; 674 goto bad; 675 } 676 677 /* 678 * protection against faulty packet - there should be 679 * more sanity checks in header chain processing. 680 */ 681 if (m->m_pkthdr.len < off) { 682 ip6stat.ip6s_tooshort++; 683 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 684 goto bad; 685 } 686 687 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 688 } 689 return; 690 bad: 691 m_freem(m); 692 } 693 694 /* 695 * Hop-by-Hop options header processing. If a valid jumbo payload option is 696 * included, the real payload length will be stored in plenp. 697 */ 698 static int 699 ip6_hopopts_input(plenp, rtalertp, mp, offp) 700 u_int32_t *plenp; 701 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 702 struct mbuf **mp; 703 int *offp; 704 { 705 register struct mbuf *m = *mp; 706 int off = *offp, hbhlen; 707 struct ip6_hbh *hbh; 708 u_int8_t *opt; 709 710 /* validation of the length of the header */ 711 #ifndef PULLDOWN_TEST 712 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 713 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 714 hbhlen = (hbh->ip6h_len + 1) << 3; 715 716 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 717 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 718 #else 719 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 720 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 721 if (hbh == NULL) { 722 ip6stat.ip6s_tooshort++; 723 return -1; 724 } 725 hbhlen = (hbh->ip6h_len + 1) << 3; 726 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 727 hbhlen); 728 if (hbh == NULL) { 729 ip6stat.ip6s_tooshort++; 730 return -1; 731 } 732 #endif 733 off += hbhlen; 734 hbhlen -= sizeof(struct ip6_hbh); 735 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 736 737 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 738 hbhlen, rtalertp, plenp) < 0) 739 return(-1); 740 741 *offp = off; 742 *mp = m; 743 return(0); 744 } 745 746 /* 747 * Search header for all Hop-by-hop options and process each option. 748 * This function is separate from ip6_hopopts_input() in order to 749 * handle a case where the sending node itself process its hop-by-hop 750 * options header. In such a case, the function is called from ip6_output(). 751 */ 752 int 753 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 754 struct mbuf *m; 755 u_int8_t *opthead; 756 int hbhlen; 757 u_int32_t *rtalertp; 758 u_int32_t *plenp; 759 { 760 struct ip6_hdr *ip6; 761 int optlen = 0; 762 u_int8_t *opt = opthead; 763 u_int16_t rtalert_val; 764 u_int32_t jumboplen; 765 766 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 767 switch(*opt) { 768 case IP6OPT_PAD1: 769 optlen = 1; 770 break; 771 case IP6OPT_PADN: 772 if (hbhlen < IP6OPT_MINLEN) { 773 ip6stat.ip6s_toosmall++; 774 goto bad; 775 } 776 optlen = *(opt + 1) + 2; 777 break; 778 case IP6OPT_RTALERT: 779 /* XXX may need check for alignment */ 780 if (hbhlen < IP6OPT_RTALERT_LEN) { 781 ip6stat.ip6s_toosmall++; 782 goto bad; 783 } 784 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) 785 /* XXX: should we discard the packet? */ 786 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 787 *(opt + 1)); 788 optlen = IP6OPT_RTALERT_LEN; 789 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 790 *rtalertp = ntohs(rtalert_val); 791 break; 792 case IP6OPT_JUMBO: 793 /* XXX may need check for alignment */ 794 if (hbhlen < IP6OPT_JUMBO_LEN) { 795 ip6stat.ip6s_toosmall++; 796 goto bad; 797 } 798 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) 799 /* XXX: should we discard the packet? */ 800 log(LOG_ERR, "length of jumbopayload opt " 801 "is inconsistent(%d)", 802 *(opt + 1)); 803 optlen = IP6OPT_JUMBO_LEN; 804 805 /* 806 * IPv6 packets that have non 0 payload length 807 * must not contain a jumbo paylod option. 808 */ 809 ip6 = mtod(m, struct ip6_hdr *); 810 if (ip6->ip6_plen) { 811 ip6stat.ip6s_badoptions++; 812 icmp6_error(m, ICMP6_PARAM_PROB, 813 ICMP6_PARAMPROB_HEADER, 814 sizeof(struct ip6_hdr) + 815 sizeof(struct ip6_hbh) + 816 opt - opthead); 817 return(-1); 818 } 819 820 /* 821 * We may see jumbolen in unaligned location, so 822 * we'd need to perform bcopy(). 823 */ 824 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 825 jumboplen = (u_int32_t)htonl(jumboplen); 826 827 #if 1 828 /* 829 * if there are multiple jumbo payload options, 830 * *plenp will be non-zero and the packet will be 831 * rejected. 832 * the behavior may need some debate in ipngwg - 833 * multiple options does not make sense, however, 834 * there's no explicit mention in specification. 835 */ 836 if (*plenp != 0) { 837 ip6stat.ip6s_badoptions++; 838 icmp6_error(m, ICMP6_PARAM_PROB, 839 ICMP6_PARAMPROB_HEADER, 840 sizeof(struct ip6_hdr) + 841 sizeof(struct ip6_hbh) + 842 opt + 2 - opthead); 843 return(-1); 844 } 845 #endif 846 847 /* 848 * jumbo payload length must be larger than 65535. 849 */ 850 if (jumboplen <= IPV6_MAXPACKET) { 851 ip6stat.ip6s_badoptions++; 852 icmp6_error(m, ICMP6_PARAM_PROB, 853 ICMP6_PARAMPROB_HEADER, 854 sizeof(struct ip6_hdr) + 855 sizeof(struct ip6_hbh) + 856 opt + 2 - opthead); 857 return(-1); 858 } 859 *plenp = jumboplen; 860 861 break; 862 default: /* unknown option */ 863 if (hbhlen < IP6OPT_MINLEN) { 864 ip6stat.ip6s_toosmall++; 865 goto bad; 866 } 867 if ((optlen = ip6_unknown_opt(opt, m, 868 sizeof(struct ip6_hdr) + 869 sizeof(struct ip6_hbh) + 870 opt - opthead)) == -1) 871 return(-1); 872 optlen += 2; 873 break; 874 } 875 } 876 877 return(0); 878 879 bad: 880 m_freem(m); 881 return(-1); 882 } 883 884 /* 885 * Unknown option processing. 886 * The third argument `off' is the offset from the IPv6 header to the option, 887 * which is necessary if the IPv6 header the and option header and IPv6 header 888 * is not continuous in order to return an ICMPv6 error. 889 */ 890 int 891 ip6_unknown_opt(optp, m, off) 892 u_int8_t *optp; 893 struct mbuf *m; 894 int off; 895 { 896 struct ip6_hdr *ip6; 897 898 switch(IP6OPT_TYPE(*optp)) { 899 case IP6OPT_TYPE_SKIP: /* ignore the option */ 900 return((int)*(optp + 1)); 901 case IP6OPT_TYPE_DISCARD: /* silently discard */ 902 m_freem(m); 903 return(-1); 904 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 905 ip6stat.ip6s_badoptions++; 906 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 907 return(-1); 908 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 909 ip6stat.ip6s_badoptions++; 910 ip6 = mtod(m, struct ip6_hdr *); 911 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 912 (m->m_flags & (M_BCAST|M_MCAST))) 913 m_freem(m); 914 else 915 icmp6_error(m, ICMP6_PARAM_PROB, 916 ICMP6_PARAMPROB_OPTION, off); 917 return(-1); 918 } 919 920 m_freem(m); /* XXX: NOTREACHED */ 921 return(-1); 922 } 923 924 /* 925 * Create the "control" list for this pcb. 926 * 927 * The routine will be called from upper layer handlers like tcp6_input(). 928 * Thus the routine assumes that the caller (tcp6_input) have already 929 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 930 * very first mbuf on the mbuf chain. 931 * We may want to add some infinite loop prevention or sanity checks for safety. 932 * (This applies only when you are using KAME mbuf chain restriction, i.e. 933 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 934 */ 935 void 936 ip6_savecontrol(in6p, mp, ip6, m) 937 register struct in6pcb *in6p; 938 register struct mbuf **mp; 939 register struct ip6_hdr *ip6; 940 register struct mbuf *m; 941 { 942 struct proc *p = curproc; /* XXX */ 943 int privileged; 944 945 privileged = 0; 946 if (p && !suser(p)) 947 privileged++; 948 949 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 950 struct timeval tv; 951 952 microtime(&tv); 953 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 954 SCM_TIMESTAMP, SOL_SOCKET); 955 if (*mp) 956 mp = &(*mp)->m_next; 957 } 958 959 #ifdef noyet 960 /* options were tossed above */ 961 if (in6p->in6p_flags & IN6P_RECVOPTS) 962 /* broken */ 963 /* ip6_srcroute doesn't do what we want here, need to fix */ 964 if (in6p->in6p_flags & IPV6P_RECVRETOPTS) 965 /* broken */ 966 #endif 967 968 /* RFC 2292 sec. 5 */ 969 if (in6p->in6p_flags & IN6P_PKTINFO) { 970 struct in6_pktinfo pi6; 971 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 972 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 973 pi6.ipi6_addr.s6_addr16[1] = 0; 974 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 975 ? m->m_pkthdr.rcvif->if_index 976 : 0; 977 *mp = sbcreatecontrol((caddr_t) &pi6, 978 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 979 IPPROTO_IPV6); 980 if (*mp) 981 mp = &(*mp)->m_next; 982 } 983 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 984 int hlim = ip6->ip6_hlim & 0xff; 985 *mp = sbcreatecontrol((caddr_t) &hlim, 986 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 987 if (*mp) 988 mp = &(*mp)->m_next; 989 } 990 /* IN6P_NEXTHOP - for outgoing packet only */ 991 992 /* 993 * IPV6_HOPOPTS socket option. We require super-user privilege 994 * for the option, but it might be too strict, since there might 995 * be some hop-by-hop options which can be returned to normal user. 996 * See RFC 2292 section 6. 997 */ 998 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 999 /* 1000 * Check if a hop-by-hop options header is contatined in the 1001 * received packet, and if so, store the options as ancillary 1002 * data. Note that a hop-by-hop options header must be 1003 * just after the IPv6 header, which fact is assured through 1004 * the IPv6 input processing. 1005 */ 1006 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1007 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1008 struct ip6_hbh *hbh; 1009 int hbhlen; 1010 1011 #ifndef PULLDOWN_TEST 1012 hbh = (struct ip6_hbh *)(ip6 + 1); 1013 hbhlen = (hbh->ip6h_len + 1) << 3; 1014 #else 1015 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1016 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1017 if (hbh == NULL) { 1018 ip6stat.ip6s_tooshort++; 1019 return; 1020 } 1021 hbhlen = (hbh->ip6h_len + 1) << 3; 1022 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1023 sizeof(struct ip6_hdr), hbhlen); 1024 if (hbh == NULL) { 1025 ip6stat.ip6s_tooshort++; 1026 return; 1027 } 1028 #endif 1029 1030 /* 1031 * XXX: We copy whole the header even if a jumbo 1032 * payload option is included, which option is to 1033 * be removed before returning in the RFC 2292. 1034 * But it's too painful operation... 1035 */ 1036 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1037 IPV6_HOPOPTS, IPPROTO_IPV6); 1038 if (*mp) 1039 mp = &(*mp)->m_next; 1040 } 1041 } 1042 1043 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1044 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 1045 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1046 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 1047 1048 /* 1049 * Search for destination options headers or routing 1050 * header(s) through the header chain, and stores each 1051 * header as ancillary data. 1052 * Note that the order of the headers remains in 1053 * the chain of ancillary data. 1054 */ 1055 while(1) { /* is explicit loop prevention necessary? */ 1056 struct ip6_ext *ip6e; 1057 int elen; 1058 1059 #ifndef PULLDOWN_TEST 1060 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1061 if (nxt == IPPROTO_AH) 1062 elen = (ip6e->ip6e_len + 2) << 2; 1063 else 1064 elen = (ip6e->ip6e_len + 1) << 3; 1065 #else 1066 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, 1067 sizeof(struct ip6_ext)); 1068 if (ip6e == NULL) { 1069 ip6stat.ip6s_tooshort++; 1070 return; 1071 } 1072 if (nxt == IPPROTO_AH) 1073 elen = (ip6e->ip6e_len + 2) << 2; 1074 else 1075 elen = (ip6e->ip6e_len + 1) << 3; 1076 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, elen); 1077 if (ip6e == NULL) { 1078 ip6stat.ip6s_tooshort++; 1079 return; 1080 } 1081 #endif 1082 1083 switch(nxt) { 1084 case IPPROTO_DSTOPTS: 1085 if (!in6p->in6p_flags & IN6P_DSTOPTS) 1086 break; 1087 1088 /* 1089 * We also require super-user privilege for 1090 * the option. 1091 * See the comments on IN6_HOPOPTS. 1092 */ 1093 if (!privileged) 1094 break; 1095 1096 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1097 IPV6_DSTOPTS, 1098 IPPROTO_IPV6); 1099 if (*mp) 1100 mp = &(*mp)->m_next; 1101 break; 1102 1103 case IPPROTO_ROUTING: 1104 if (!in6p->in6p_flags & IN6P_RTHDR) 1105 break; 1106 1107 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1108 IPV6_RTHDR, 1109 IPPROTO_IPV6); 1110 if (*mp) 1111 mp = &(*mp)->m_next; 1112 break; 1113 1114 case IPPROTO_UDP: 1115 case IPPROTO_TCP: 1116 case IPPROTO_ICMPV6: 1117 default: 1118 /* 1119 * stop search if we encounter an upper 1120 * layer protocol headers. 1121 */ 1122 goto loopend; 1123 1124 case IPPROTO_HOPOPTS: 1125 case IPPROTO_AH: /* is it possible? */ 1126 break; 1127 } 1128 1129 /* proceed with the next header. */ 1130 off += elen; 1131 nxt = ip6e->ip6e_nxt; 1132 } 1133 loopend: 1134 } 1135 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1136 /* to be done */ 1137 } 1138 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 1139 /* to be done */ 1140 } 1141 /* IN6P_RTHDR - to be done */ 1142 1143 } 1144 1145 /* 1146 * Get pointer to the previous header followed by the header 1147 * currently processed. 1148 * XXX: This function supposes that 1149 * M includes all headers, 1150 * the next header field and the header length field of each header 1151 * are valid, and 1152 * the sum of each header length equals to OFF. 1153 * Because of these assumptions, this function must be called very 1154 * carefully. Moreover, it will not be used in the near future when 1155 * we develop `neater' mechanism to process extension headers. 1156 */ 1157 char * 1158 ip6_get_prevhdr(m, off) 1159 struct mbuf *m; 1160 int off; 1161 { 1162 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1163 1164 if (off == sizeof(struct ip6_hdr)) 1165 return(&ip6->ip6_nxt); 1166 else { 1167 int len, nxt; 1168 struct ip6_ext *ip6e = NULL; 1169 1170 nxt = ip6->ip6_nxt; 1171 len = sizeof(struct ip6_hdr); 1172 while (len < off) { 1173 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1174 1175 switch(nxt) { 1176 case IPPROTO_FRAGMENT: 1177 len += sizeof(struct ip6_frag); 1178 break; 1179 case IPPROTO_AH: 1180 len += (ip6e->ip6e_len + 2) << 2; 1181 break; 1182 default: 1183 len += (ip6e->ip6e_len + 1) << 3; 1184 break; 1185 } 1186 nxt = ip6e->ip6e_nxt; 1187 } 1188 if (ip6e) 1189 return(&ip6e->ip6e_nxt); 1190 else 1191 return NULL; 1192 } 1193 } 1194 1195 /* 1196 * get next header offset. m will be retained. 1197 */ 1198 int 1199 ip6_nexthdr(m, off, proto, nxtp) 1200 struct mbuf *m; 1201 int off; 1202 int proto; 1203 int *nxtp; 1204 { 1205 struct ip6_hdr ip6; 1206 struct ip6_ext ip6e; 1207 struct ip6_frag fh; 1208 1209 /* just in case */ 1210 if (m == NULL) 1211 panic("ip6_nexthdr: m == NULL"); 1212 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1213 return -1; 1214 1215 switch (proto) { 1216 case IPPROTO_IPV6: 1217 if (m->m_pkthdr.len < off + sizeof(ip6)) 1218 return -1; 1219 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1220 if (nxtp) 1221 *nxtp = ip6.ip6_nxt; 1222 off += sizeof(ip6); 1223 return off; 1224 1225 case IPPROTO_FRAGMENT: 1226 /* 1227 * terminate parsing if it is not the first fragment, 1228 * it does not make sense to parse through it. 1229 */ 1230 if (m->m_pkthdr.len < off + sizeof(fh)) 1231 return -1; 1232 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1233 if ((ntohs(fh.ip6f_offlg) & IP6F_OFF_MASK) != 0) 1234 return -1; 1235 if (nxtp) 1236 *nxtp = fh.ip6f_nxt; 1237 off += sizeof(struct ip6_frag); 1238 return off; 1239 1240 case IPPROTO_AH: 1241 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1242 return -1; 1243 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1244 if (nxtp) 1245 *nxtp = ip6e.ip6e_nxt; 1246 off += (ip6e.ip6e_len + 2) << 2; 1247 return off; 1248 1249 case IPPROTO_HOPOPTS: 1250 case IPPROTO_ROUTING: 1251 case IPPROTO_DSTOPTS: 1252 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1253 return -1; 1254 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1255 if (nxtp) 1256 *nxtp = ip6e.ip6e_nxt; 1257 off += (ip6e.ip6e_len + 1) << 3; 1258 return off; 1259 1260 case IPPROTO_NONE: 1261 case IPPROTO_ESP: 1262 case IPPROTO_IPCOMP: 1263 /* give up */ 1264 return -1; 1265 1266 default: 1267 return -1; 1268 } 1269 1270 return -1; 1271 } 1272 1273 /* 1274 * get offset for the last header in the chain. m will be kept untainted. 1275 */ 1276 int 1277 ip6_lasthdr(m, off, proto, nxtp) 1278 struct mbuf *m; 1279 int off; 1280 int proto; 1281 int *nxtp; 1282 { 1283 int newoff; 1284 int nxt; 1285 1286 if (!nxtp) { 1287 nxt = -1; 1288 nxtp = &nxt; 1289 } 1290 while (1) { 1291 newoff = ip6_nexthdr(m, off, proto, nxtp); 1292 if (newoff < 0) 1293 return off; 1294 else if (newoff < off) 1295 return -1; /* invalid */ 1296 else if (newoff == off) 1297 return newoff; 1298 1299 off = newoff; 1300 proto = *nxtp; 1301 } 1302 } 1303 1304 /* 1305 * System control for IP6 1306 */ 1307 1308 u_char inet6ctlerrmap[PRC_NCMDS] = { 1309 0, 0, 0, 0, 1310 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1311 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1312 EMSGSIZE, EHOSTUNREACH, 0, 0, 1313 0, 0, 0, 0, 1314 ENOPROTOOPT 1315 }; 1316