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 mtx_init(&ip6intrq.ifq_mtx, "ip6_inq", MTX_DEF); 171 register_netisr(NETISR_IPV6, ip6intr); 172 nd6_init(); 173 frag6_init(); 174 /* 175 * in many cases, random() here does NOT return random number 176 * as initialization during bootstrap time occur in fixed order. 177 */ 178 microtime(&tv); 179 ip6_flow_seq = random() ^ tv.tv_usec; 180 } 181 182 static void 183 ip6_init2(dummy) 184 void *dummy; 185 { 186 187 /* 188 * to route local address of p2p link to loopback, 189 * assign loopback address first. 190 */ 191 in6_ifattach(&loif[0], NULL); 192 193 /* nd6_timer_init */ 194 timeout(nd6_timer, (caddr_t)0, hz); 195 /* router renumbering prefix list maintenance */ 196 timeout(in6_rr_timer, (caddr_t)0, hz); 197 } 198 199 /* cheat */ 200 /* This must be after route_init(), which is now SI_ORDER_THIRD */ 201 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL); 202 203 /* 204 * IP6 input interrupt handling. Just pass the packet to ip6_input. 205 */ 206 void 207 ip6intr() 208 { 209 int s; 210 struct mbuf *m; 211 212 for (;;) { 213 s = splimp(); 214 IF_DEQUEUE(&ip6intrq, m); 215 splx(s); 216 if (m == 0) 217 return; 218 ip6_input(m); 219 } 220 } 221 222 extern struct route_in6 ip6_forward_rt; 223 224 void 225 ip6_input(m) 226 struct mbuf *m; 227 { 228 struct ip6_hdr *ip6; 229 int off = sizeof(struct ip6_hdr), nest; 230 u_int32_t plen; 231 u_int32_t rtalert = ~0; 232 int nxt, ours = 0; 233 struct ifnet *deliverifp = NULL; 234 #ifdef PFIL_HOOKS 235 struct packet_filter_hook *pfh; 236 struct mbuf *m0; 237 int rv; 238 #endif /* PFIL_HOOKS */ 239 240 #ifdef IPSEC 241 /* 242 * should the inner packet be considered authentic? 243 * see comment in ah4_input(). 244 */ 245 if (m) { 246 m->m_flags &= ~M_AUTHIPHDR; 247 m->m_flags &= ~M_AUTHIPDGM; 248 } 249 #endif 250 251 /* 252 * mbuf statistics by kazu 253 */ 254 if (m->m_flags & M_EXT) { 255 if (m->m_next) 256 ip6stat.ip6s_mext2m++; 257 else 258 ip6stat.ip6s_mext1++; 259 } else { 260 if (m->m_next) { 261 if (m->m_flags & M_LOOP) { 262 ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/ 263 } else if (m->m_pkthdr.rcvif->if_index <= 31) 264 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 265 else 266 ip6stat.ip6s_m2m[0]++; 267 } else 268 ip6stat.ip6s_m1++; 269 } 270 271 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 272 ip6stat.ip6s_total++; 273 274 #ifndef PULLDOWN_TEST 275 /* XXX is the line really necessary? */ 276 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/); 277 #endif 278 279 if (m->m_len < sizeof(struct ip6_hdr)) { 280 struct ifnet *inifp; 281 inifp = m->m_pkthdr.rcvif; 282 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 283 ip6stat.ip6s_toosmall++; 284 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 285 return; 286 } 287 } 288 289 ip6 = mtod(m, struct ip6_hdr *); 290 291 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 292 ip6stat.ip6s_badvers++; 293 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 294 goto bad; 295 } 296 297 #ifdef PFIL_HOOKS 298 /* 299 * Run through list of hooks for input packets. If there are any 300 * filters which require that additional packets in the flow are 301 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 302 * Note that filters must _never_ set this flag, as another filter 303 * in the list may have previously cleared it. 304 */ 305 m0 = m; 306 pfh = pfil_hook_get(PFIL_IN, &inet6sw[ip6_protox[IPPROTO_IPV6]].pr_pfh); 307 for (; pfh; pfh = pfh->pfil_link.tqe_next) 308 if (pfh->pfil_func) { 309 rv = pfh->pfil_func(ip6, sizeof(*ip6), 310 m->m_pkthdr.rcvif, 0, &m0); 311 if (rv) 312 return; 313 m = m0; 314 if (m == NULL) 315 return; 316 ip6 = mtod(m, struct ip6_hdr *); 317 } 318 #endif /* PFIL_HOOKS */ 319 320 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 321 322 /* 323 * Check with the firewall... 324 */ 325 if (ip6_fw_enable && ip6_fw_chk_ptr) { 326 u_short port = 0; 327 /* If ipfw says divert, we have to just drop packet */ 328 /* use port as a dummy argument */ 329 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) { 330 m_freem(m); 331 m = NULL; 332 } 333 if (!m) 334 return; 335 } 336 337 /* 338 * Scope check 339 */ 340 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 341 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 342 ip6stat.ip6s_badscope++; 343 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 344 goto bad; 345 } 346 347 /* 348 * Don't check IPv4 mapped address here. SIIT assumes that 349 * routers would forward IPv6 native packets with IPv4 mapped 350 * address normally. 351 */ 352 #if 0 353 /* 354 * Reject packets with IPv4 compatible addresses (auto tunnel). 355 * 356 * The code forbids auto tunnel relay case in RFC1933 (the check is 357 * stronger than RFC1933). We may want to re-enable it if mech-xx 358 * is revised to forbid relaying case. 359 */ 360 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 361 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 362 ip6stat.ip6s_badscope++; 363 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 364 goto bad; 365 } 366 #endif 367 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 368 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 369 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 370 ours = 1; 371 deliverifp = m->m_pkthdr.rcvif; 372 goto hbhcheck; 373 } else { 374 ip6stat.ip6s_badscope++; 375 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 376 goto bad; 377 } 378 } 379 380 #ifndef FAKE_LOOPBACK_IF 381 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) 382 #else 383 if (1) 384 #endif 385 { 386 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 387 ip6->ip6_src.s6_addr16[1] 388 = htons(m->m_pkthdr.rcvif->if_index); 389 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 390 ip6->ip6_dst.s6_addr16[1] 391 = htons(m->m_pkthdr.rcvif->if_index); 392 } 393 394 /* 395 * XXX we need this since we do not have "goto ours" hack route 396 * for some of our ifaddrs on loopback interface. 397 * we should correct it by changing in6_ifattach to install 398 * "goto ours" hack route. 399 */ 400 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) != 0) { 401 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 402 ours = 1; 403 deliverifp = m->m_pkthdr.rcvif; 404 goto hbhcheck; 405 } 406 } 407 408 /* 409 * Multicast check 410 */ 411 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 412 struct in6_multi *in6m = 0; 413 414 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 415 /* 416 * See if we belong to the destination multicast group on the 417 * arrival interface. 418 */ 419 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 420 if (in6m) 421 ours = 1; 422 else if (!ip6_mrouter) { 423 ip6stat.ip6s_notmember++; 424 ip6stat.ip6s_cantforward++; 425 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 426 goto bad; 427 } 428 deliverifp = m->m_pkthdr.rcvif; 429 goto hbhcheck; 430 } 431 432 /* 433 * Unicast check 434 */ 435 if (ip6_forward_rt.ro_rt != NULL && 436 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) != 0 && 437 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 438 &ip6_forward_rt.ro_dst.sin6_addr)) 439 ip6stat.ip6s_forward_cachehit++; 440 else { 441 if (ip6_forward_rt.ro_rt) { 442 /* route is down or destination is different */ 443 ip6stat.ip6s_forward_cachemiss++; 444 RTFREE(ip6_forward_rt.ro_rt); 445 ip6_forward_rt.ro_rt = 0; 446 } 447 448 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 449 ip6_forward_rt.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 450 ip6_forward_rt.ro_dst.sin6_family = AF_INET6; 451 ip6_forward_rt.ro_dst.sin6_addr = ip6->ip6_dst; 452 #ifdef SCOPEDROUTING 453 ip6_forward_rt.ro_dst.sin6_scope_id = 454 in6_addr2scopeid(m->m_pkthdr.rcvif, &ip6->ip6_dst); 455 #endif 456 457 rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING); 458 } 459 460 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 461 462 /* 463 * Accept the packet if the forwarding interface to the destination 464 * according to the routing table is the loopback interface, 465 * unless the associated route has a gateway. 466 * Note that this approach causes to accept a packet if there is a 467 * route to the loopback interface for the destination of the packet. 468 * But we think it's even useful in some situations, e.g. when using 469 * a special daemon which wants to intercept the packet. 470 */ 471 if (ip6_forward_rt.ro_rt && 472 (ip6_forward_rt.ro_rt->rt_flags & 473 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 474 #if 0 475 /* 476 * The check below is redundant since the comparison of 477 * the destination and the key of the rtentry has 478 * already done through looking up the routing table. 479 */ 480 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 481 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) && 482 #endif 483 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 484 struct in6_ifaddr *ia6 = 485 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 486 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 487 m->m_flags |= M_ANYCAST6; 488 /* 489 * packets to a tentative, duplicated, or somehow invalid 490 * address must not be accepted. 491 */ 492 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 493 /* this address is ready */ 494 ours = 1; 495 deliverifp = ia6->ia_ifp; /* correct? */ 496 497 /* Count the packet in the ip address stats */ 498 ia6->ia_ifa.if_ipackets++; 499 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len; 500 501 goto hbhcheck; 502 } else { 503 /* address is not ready, so discard the packet. */ 504 log(LOG_INFO, 505 "ip6_input: packet to an unready address %s->%s", 506 ip6_sprintf(&ip6->ip6_src), 507 ip6_sprintf(&ip6->ip6_dst)); 508 509 goto bad; 510 } 511 } 512 513 /* 514 * FAITH(Firewall Aided Internet Translator) 515 */ 516 #if defined(NFAITH) && 0 < NFAITH 517 if (ip6_keepfaith) { 518 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 519 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 520 /* XXX do we need more sanity checks? */ 521 ours = 1; 522 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 523 goto hbhcheck; 524 } 525 } 526 #endif 527 528 /* 529 * Now there is no reason to process the packet if it's not our own 530 * and we're not a router. 531 */ 532 if (!ip6_forwarding) { 533 ip6stat.ip6s_cantforward++; 534 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 535 goto bad; 536 } 537 538 hbhcheck: 539 /* 540 * Process Hop-by-Hop options header if it's contained. 541 * m may be modified in ip6_hopopts_input(). 542 * If a JumboPayload option is included, plen will also be modified. 543 */ 544 plen = (u_int32_t)ntohs(ip6->ip6_plen); 545 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 546 struct ip6_hbh *hbh; 547 548 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 549 #if 0 /*touches NULL pointer*/ 550 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 551 #endif 552 return; /* m have already been freed */ 553 } 554 555 /* adjust pointer */ 556 ip6 = mtod(m, struct ip6_hdr *); 557 558 /* 559 * if the payload length field is 0 and the next header field 560 * indicates Hop-by-Hop Options header, then a Jumbo Payload 561 * option MUST be included. 562 */ 563 if (ip6->ip6_plen == 0 && plen == 0) { 564 /* 565 * Note that if a valid jumbo payload option is 566 * contained, ip6_hoptops_input() must set a valid 567 * (non-zero) payload length to the variable plen. 568 */ 569 ip6stat.ip6s_badoptions++; 570 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 571 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 572 icmp6_error(m, ICMP6_PARAM_PROB, 573 ICMP6_PARAMPROB_HEADER, 574 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 575 return; 576 } 577 #ifndef PULLDOWN_TEST 578 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 579 hbh = (struct ip6_hbh *)(ip6 + 1); 580 #else 581 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 582 sizeof(struct ip6_hbh)); 583 if (hbh == NULL) { 584 ip6stat.ip6s_tooshort++; 585 return; 586 } 587 #endif 588 nxt = hbh->ip6h_nxt; 589 590 /* 591 * accept the packet if a router alert option is included 592 * and we act as an IPv6 router. 593 */ 594 if (rtalert != ~0 && ip6_forwarding) 595 ours = 1; 596 } else 597 nxt = ip6->ip6_nxt; 598 599 /* 600 * Check that the amount of data in the buffers 601 * is as at least much as the IPv6 header would have us expect. 602 * Trim mbufs if longer than we expect. 603 * Drop packet if shorter than we expect. 604 */ 605 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 606 ip6stat.ip6s_tooshort++; 607 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 608 goto bad; 609 } 610 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 611 if (m->m_len == m->m_pkthdr.len) { 612 m->m_len = sizeof(struct ip6_hdr) + plen; 613 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 614 } else 615 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 616 } 617 618 /* 619 * Forward if desirable. 620 */ 621 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 622 /* 623 * If we are acting as a multicast router, all 624 * incoming multicast packets are passed to the 625 * kernel-level multicast forwarding function. 626 * The packet is returned (relatively) intact; if 627 * ip6_mforward() returns a non-zero value, the packet 628 * must be discarded, else it may be accepted below. 629 */ 630 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 631 ip6stat.ip6s_cantforward++; 632 m_freem(m); 633 return; 634 } 635 if (!ours) { 636 m_freem(m); 637 return; 638 } 639 } else if (!ours) { 640 ip6_forward(m, 0); 641 return; 642 } 643 644 ip6 = mtod(m, struct ip6_hdr *); 645 646 /* 647 * Malicious party may be able to use IPv4 mapped addr to confuse 648 * tcp/udp stack and bypass security checks (act as if it was from 649 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 650 * 651 * For SIIT end node behavior, you may want to disable the check. 652 * However, you will become vulnerable to attacks using IPv4 mapped 653 * source. 654 */ 655 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 656 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 657 ip6stat.ip6s_badscope++; 658 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 659 goto bad; 660 } 661 662 /* 663 * Tell launch routine the next header 664 */ 665 ip6stat.ip6s_delivered++; 666 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 667 nest = 0; 668 while (nxt != IPPROTO_DONE) { 669 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 670 ip6stat.ip6s_toomanyhdr++; 671 goto bad; 672 } 673 674 /* 675 * protection against faulty packet - there should be 676 * more sanity checks in header chain processing. 677 */ 678 if (m->m_pkthdr.len < off) { 679 ip6stat.ip6s_tooshort++; 680 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 681 goto bad; 682 } 683 684 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 685 } 686 return; 687 bad: 688 m_freem(m); 689 } 690 691 /* 692 * Hop-by-Hop options header processing. If a valid jumbo payload option is 693 * included, the real payload length will be stored in plenp. 694 */ 695 static int 696 ip6_hopopts_input(plenp, rtalertp, mp, offp) 697 u_int32_t *plenp; 698 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 699 struct mbuf **mp; 700 int *offp; 701 { 702 register struct mbuf *m = *mp; 703 int off = *offp, hbhlen; 704 struct ip6_hbh *hbh; 705 u_int8_t *opt; 706 707 /* validation of the length of the header */ 708 #ifndef PULLDOWN_TEST 709 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 710 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 711 hbhlen = (hbh->ip6h_len + 1) << 3; 712 713 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 714 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 715 #else 716 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 717 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 718 if (hbh == NULL) { 719 ip6stat.ip6s_tooshort++; 720 return -1; 721 } 722 hbhlen = (hbh->ip6h_len + 1) << 3; 723 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 724 hbhlen); 725 if (hbh == NULL) { 726 ip6stat.ip6s_tooshort++; 727 return -1; 728 } 729 #endif 730 off += hbhlen; 731 hbhlen -= sizeof(struct ip6_hbh); 732 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 733 734 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 735 hbhlen, rtalertp, plenp) < 0) 736 return(-1); 737 738 *offp = off; 739 *mp = m; 740 return(0); 741 } 742 743 /* 744 * Search header for all Hop-by-hop options and process each option. 745 * This function is separate from ip6_hopopts_input() in order to 746 * handle a case where the sending node itself process its hop-by-hop 747 * options header. In such a case, the function is called from ip6_output(). 748 */ 749 int 750 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 751 struct mbuf *m; 752 u_int8_t *opthead; 753 int hbhlen; 754 u_int32_t *rtalertp; 755 u_int32_t *plenp; 756 { 757 struct ip6_hdr *ip6; 758 int optlen = 0; 759 u_int8_t *opt = opthead; 760 u_int16_t rtalert_val; 761 u_int32_t jumboplen; 762 763 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 764 switch(*opt) { 765 case IP6OPT_PAD1: 766 optlen = 1; 767 break; 768 case IP6OPT_PADN: 769 if (hbhlen < IP6OPT_MINLEN) { 770 ip6stat.ip6s_toosmall++; 771 goto bad; 772 } 773 optlen = *(opt + 1) + 2; 774 break; 775 case IP6OPT_RTALERT: 776 /* XXX may need check for alignment */ 777 if (hbhlen < IP6OPT_RTALERT_LEN) { 778 ip6stat.ip6s_toosmall++; 779 goto bad; 780 } 781 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) 782 /* XXX: should we discard the packet? */ 783 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 784 *(opt + 1)); 785 optlen = IP6OPT_RTALERT_LEN; 786 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 787 *rtalertp = ntohs(rtalert_val); 788 break; 789 case IP6OPT_JUMBO: 790 /* XXX may need check for alignment */ 791 if (hbhlen < IP6OPT_JUMBO_LEN) { 792 ip6stat.ip6s_toosmall++; 793 goto bad; 794 } 795 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) 796 /* XXX: should we discard the packet? */ 797 log(LOG_ERR, "length of jumbopayload opt " 798 "is inconsistent(%d)", 799 *(opt + 1)); 800 optlen = IP6OPT_JUMBO_LEN; 801 802 /* 803 * IPv6 packets that have non 0 payload length 804 * must not contain a jumbo paylod option. 805 */ 806 ip6 = mtod(m, struct ip6_hdr *); 807 if (ip6->ip6_plen) { 808 ip6stat.ip6s_badoptions++; 809 icmp6_error(m, ICMP6_PARAM_PROB, 810 ICMP6_PARAMPROB_HEADER, 811 sizeof(struct ip6_hdr) + 812 sizeof(struct ip6_hbh) + 813 opt - opthead); 814 return(-1); 815 } 816 817 /* 818 * We may see jumbolen in unaligned location, so 819 * we'd need to perform bcopy(). 820 */ 821 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 822 jumboplen = (u_int32_t)htonl(jumboplen); 823 824 #if 1 825 /* 826 * if there are multiple jumbo payload options, 827 * *plenp will be non-zero and the packet will be 828 * rejected. 829 * the behavior may need some debate in ipngwg - 830 * multiple options does not make sense, however, 831 * there's no explicit mention in specification. 832 */ 833 if (*plenp != 0) { 834 ip6stat.ip6s_badoptions++; 835 icmp6_error(m, ICMP6_PARAM_PROB, 836 ICMP6_PARAMPROB_HEADER, 837 sizeof(struct ip6_hdr) + 838 sizeof(struct ip6_hbh) + 839 opt + 2 - opthead); 840 return(-1); 841 } 842 #endif 843 844 /* 845 * jumbo payload length must be larger than 65535. 846 */ 847 if (jumboplen <= IPV6_MAXPACKET) { 848 ip6stat.ip6s_badoptions++; 849 icmp6_error(m, ICMP6_PARAM_PROB, 850 ICMP6_PARAMPROB_HEADER, 851 sizeof(struct ip6_hdr) + 852 sizeof(struct ip6_hbh) + 853 opt + 2 - opthead); 854 return(-1); 855 } 856 *plenp = jumboplen; 857 858 break; 859 default: /* unknown option */ 860 if (hbhlen < IP6OPT_MINLEN) { 861 ip6stat.ip6s_toosmall++; 862 goto bad; 863 } 864 if ((optlen = ip6_unknown_opt(opt, m, 865 sizeof(struct ip6_hdr) + 866 sizeof(struct ip6_hbh) + 867 opt - opthead)) == -1) 868 return(-1); 869 optlen += 2; 870 break; 871 } 872 } 873 874 return(0); 875 876 bad: 877 m_freem(m); 878 return(-1); 879 } 880 881 /* 882 * Unknown option processing. 883 * The third argument `off' is the offset from the IPv6 header to the option, 884 * which is necessary if the IPv6 header the and option header and IPv6 header 885 * is not continuous in order to return an ICMPv6 error. 886 */ 887 int 888 ip6_unknown_opt(optp, m, off) 889 u_int8_t *optp; 890 struct mbuf *m; 891 int off; 892 { 893 struct ip6_hdr *ip6; 894 895 switch(IP6OPT_TYPE(*optp)) { 896 case IP6OPT_TYPE_SKIP: /* ignore the option */ 897 return((int)*(optp + 1)); 898 case IP6OPT_TYPE_DISCARD: /* silently discard */ 899 m_freem(m); 900 return(-1); 901 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 902 ip6stat.ip6s_badoptions++; 903 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 904 return(-1); 905 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 906 ip6stat.ip6s_badoptions++; 907 ip6 = mtod(m, struct ip6_hdr *); 908 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 909 (m->m_flags & (M_BCAST|M_MCAST))) 910 m_freem(m); 911 else 912 icmp6_error(m, ICMP6_PARAM_PROB, 913 ICMP6_PARAMPROB_OPTION, off); 914 return(-1); 915 } 916 917 m_freem(m); /* XXX: NOTREACHED */ 918 return(-1); 919 } 920 921 /* 922 * Create the "control" list for this pcb. 923 * 924 * The routine will be called from upper layer handlers like tcp6_input(). 925 * Thus the routine assumes that the caller (tcp6_input) have already 926 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 927 * very first mbuf on the mbuf chain. 928 * We may want to add some infinite loop prevention or sanity checks for safety. 929 * (This applies only when you are using KAME mbuf chain restriction, i.e. 930 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 931 */ 932 void 933 ip6_savecontrol(in6p, mp, ip6, m) 934 register struct in6pcb *in6p; 935 register struct mbuf **mp; 936 register struct ip6_hdr *ip6; 937 register struct mbuf *m; 938 { 939 struct proc *p = curproc; /* XXX */ 940 int privileged; 941 942 privileged = 0; 943 if (p && !suser(p)) 944 privileged++; 945 946 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 947 struct timeval tv; 948 949 microtime(&tv); 950 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 951 SCM_TIMESTAMP, SOL_SOCKET); 952 if (*mp) 953 mp = &(*mp)->m_next; 954 } 955 956 #ifdef noyet 957 /* options were tossed above */ 958 if (in6p->in6p_flags & IN6P_RECVOPTS) 959 /* broken */ 960 /* ip6_srcroute doesn't do what we want here, need to fix */ 961 if (in6p->in6p_flags & IPV6P_RECVRETOPTS) 962 /* broken */ 963 #endif 964 965 /* RFC 2292 sec. 5 */ 966 if (in6p->in6p_flags & IN6P_PKTINFO) { 967 struct in6_pktinfo pi6; 968 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 969 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 970 pi6.ipi6_addr.s6_addr16[1] = 0; 971 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 972 ? m->m_pkthdr.rcvif->if_index 973 : 0; 974 *mp = sbcreatecontrol((caddr_t) &pi6, 975 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 976 IPPROTO_IPV6); 977 if (*mp) 978 mp = &(*mp)->m_next; 979 } 980 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 981 int hlim = ip6->ip6_hlim & 0xff; 982 *mp = sbcreatecontrol((caddr_t) &hlim, 983 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 984 if (*mp) 985 mp = &(*mp)->m_next; 986 } 987 /* IN6P_NEXTHOP - for outgoing packet only */ 988 989 /* 990 * IPV6_HOPOPTS socket option. We require super-user privilege 991 * for the option, but it might be too strict, since there might 992 * be some hop-by-hop options which can be returned to normal user. 993 * See RFC 2292 section 6. 994 */ 995 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 996 /* 997 * Check if a hop-by-hop options header is contatined in the 998 * received packet, and if so, store the options as ancillary 999 * data. Note that a hop-by-hop options header must be 1000 * just after the IPv6 header, which fact is assured through 1001 * the IPv6 input processing. 1002 */ 1003 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1004 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1005 struct ip6_hbh *hbh; 1006 int hbhlen; 1007 1008 #ifndef PULLDOWN_TEST 1009 hbh = (struct ip6_hbh *)(ip6 + 1); 1010 hbhlen = (hbh->ip6h_len + 1) << 3; 1011 #else 1012 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1013 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1014 if (hbh == NULL) { 1015 ip6stat.ip6s_tooshort++; 1016 return; 1017 } 1018 hbhlen = (hbh->ip6h_len + 1) << 3; 1019 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1020 sizeof(struct ip6_hdr), hbhlen); 1021 if (hbh == NULL) { 1022 ip6stat.ip6s_tooshort++; 1023 return; 1024 } 1025 #endif 1026 1027 /* 1028 * XXX: We copy whole the header even if a jumbo 1029 * payload option is included, which option is to 1030 * be removed before returning in the RFC 2292. 1031 * But it's too painful operation... 1032 */ 1033 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1034 IPV6_HOPOPTS, IPPROTO_IPV6); 1035 if (*mp) 1036 mp = &(*mp)->m_next; 1037 } 1038 } 1039 1040 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1041 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 1042 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1043 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 1044 1045 /* 1046 * Search for destination options headers or routing 1047 * header(s) through the header chain, and stores each 1048 * header as ancillary data. 1049 * Note that the order of the headers remains in 1050 * the chain of ancillary data. 1051 */ 1052 while(1) { /* is explicit loop prevention necessary? */ 1053 struct ip6_ext *ip6e; 1054 int elen; 1055 1056 #ifndef PULLDOWN_TEST 1057 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1058 if (nxt == IPPROTO_AH) 1059 elen = (ip6e->ip6e_len + 2) << 2; 1060 else 1061 elen = (ip6e->ip6e_len + 1) << 3; 1062 #else 1063 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, 1064 sizeof(struct ip6_ext)); 1065 if (ip6e == NULL) { 1066 ip6stat.ip6s_tooshort++; 1067 return; 1068 } 1069 if (nxt == IPPROTO_AH) 1070 elen = (ip6e->ip6e_len + 2) << 2; 1071 else 1072 elen = (ip6e->ip6e_len + 1) << 3; 1073 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, elen); 1074 if (ip6e == NULL) { 1075 ip6stat.ip6s_tooshort++; 1076 return; 1077 } 1078 #endif 1079 1080 switch(nxt) { 1081 case IPPROTO_DSTOPTS: 1082 if (!in6p->in6p_flags & IN6P_DSTOPTS) 1083 break; 1084 1085 /* 1086 * We also require super-user privilege for 1087 * the option. 1088 * See the comments on IN6_HOPOPTS. 1089 */ 1090 if (!privileged) 1091 break; 1092 1093 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1094 IPV6_DSTOPTS, 1095 IPPROTO_IPV6); 1096 if (*mp) 1097 mp = &(*mp)->m_next; 1098 break; 1099 1100 case IPPROTO_ROUTING: 1101 if (!in6p->in6p_flags & IN6P_RTHDR) 1102 break; 1103 1104 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1105 IPV6_RTHDR, 1106 IPPROTO_IPV6); 1107 if (*mp) 1108 mp = &(*mp)->m_next; 1109 break; 1110 1111 case IPPROTO_UDP: 1112 case IPPROTO_TCP: 1113 case IPPROTO_ICMPV6: 1114 default: 1115 /* 1116 * stop search if we encounter an upper 1117 * layer protocol headers. 1118 */ 1119 goto loopend; 1120 1121 case IPPROTO_HOPOPTS: 1122 case IPPROTO_AH: /* is it possible? */ 1123 break; 1124 } 1125 1126 /* proceed with the next header. */ 1127 off += elen; 1128 nxt = ip6e->ip6e_nxt; 1129 } 1130 loopend: 1131 } 1132 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1133 /* to be done */ 1134 } 1135 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 1136 /* to be done */ 1137 } 1138 /* IN6P_RTHDR - to be done */ 1139 1140 } 1141 1142 /* 1143 * Get pointer to the previous header followed by the header 1144 * currently processed. 1145 * XXX: This function supposes that 1146 * M includes all headers, 1147 * the next header field and the header length field of each header 1148 * are valid, and 1149 * the sum of each header length equals to OFF. 1150 * Because of these assumptions, this function must be called very 1151 * carefully. Moreover, it will not be used in the near future when 1152 * we develop `neater' mechanism to process extension headers. 1153 */ 1154 char * 1155 ip6_get_prevhdr(m, off) 1156 struct mbuf *m; 1157 int off; 1158 { 1159 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1160 1161 if (off == sizeof(struct ip6_hdr)) 1162 return(&ip6->ip6_nxt); 1163 else { 1164 int len, nxt; 1165 struct ip6_ext *ip6e = NULL; 1166 1167 nxt = ip6->ip6_nxt; 1168 len = sizeof(struct ip6_hdr); 1169 while (len < off) { 1170 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1171 1172 switch(nxt) { 1173 case IPPROTO_FRAGMENT: 1174 len += sizeof(struct ip6_frag); 1175 break; 1176 case IPPROTO_AH: 1177 len += (ip6e->ip6e_len + 2) << 2; 1178 break; 1179 default: 1180 len += (ip6e->ip6e_len + 1) << 3; 1181 break; 1182 } 1183 nxt = ip6e->ip6e_nxt; 1184 } 1185 if (ip6e) 1186 return(&ip6e->ip6e_nxt); 1187 else 1188 return NULL; 1189 } 1190 } 1191 1192 /* 1193 * get next header offset. m will be retained. 1194 */ 1195 int 1196 ip6_nexthdr(m, off, proto, nxtp) 1197 struct mbuf *m; 1198 int off; 1199 int proto; 1200 int *nxtp; 1201 { 1202 struct ip6_hdr ip6; 1203 struct ip6_ext ip6e; 1204 struct ip6_frag fh; 1205 1206 /* just in case */ 1207 if (m == NULL) 1208 panic("ip6_nexthdr: m == NULL"); 1209 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1210 return -1; 1211 1212 switch (proto) { 1213 case IPPROTO_IPV6: 1214 if (m->m_pkthdr.len < off + sizeof(ip6)) 1215 return -1; 1216 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1217 if (nxtp) 1218 *nxtp = ip6.ip6_nxt; 1219 off += sizeof(ip6); 1220 return off; 1221 1222 case IPPROTO_FRAGMENT: 1223 /* 1224 * terminate parsing if it is not the first fragment, 1225 * it does not make sense to parse through it. 1226 */ 1227 if (m->m_pkthdr.len < off + sizeof(fh)) 1228 return -1; 1229 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1230 if ((ntohs(fh.ip6f_offlg) & IP6F_OFF_MASK) != 0) 1231 return -1; 1232 if (nxtp) 1233 *nxtp = fh.ip6f_nxt; 1234 off += sizeof(struct ip6_frag); 1235 return off; 1236 1237 case IPPROTO_AH: 1238 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1239 return -1; 1240 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1241 if (nxtp) 1242 *nxtp = ip6e.ip6e_nxt; 1243 off += (ip6e.ip6e_len + 2) << 2; 1244 return off; 1245 1246 case IPPROTO_HOPOPTS: 1247 case IPPROTO_ROUTING: 1248 case IPPROTO_DSTOPTS: 1249 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1250 return -1; 1251 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1252 if (nxtp) 1253 *nxtp = ip6e.ip6e_nxt; 1254 off += (ip6e.ip6e_len + 1) << 3; 1255 return off; 1256 1257 case IPPROTO_NONE: 1258 case IPPROTO_ESP: 1259 case IPPROTO_IPCOMP: 1260 /* give up */ 1261 return -1; 1262 1263 default: 1264 return -1; 1265 } 1266 1267 return -1; 1268 } 1269 1270 /* 1271 * get offset for the last header in the chain. m will be kept untainted. 1272 */ 1273 int 1274 ip6_lasthdr(m, off, proto, nxtp) 1275 struct mbuf *m; 1276 int off; 1277 int proto; 1278 int *nxtp; 1279 { 1280 int newoff; 1281 int nxt; 1282 1283 if (!nxtp) { 1284 nxt = -1; 1285 nxtp = &nxt; 1286 } 1287 while (1) { 1288 newoff = ip6_nexthdr(m, off, proto, nxtp); 1289 if (newoff < 0) 1290 return off; 1291 else if (newoff < off) 1292 return -1; /* invalid */ 1293 else if (newoff == off) 1294 return newoff; 1295 1296 off = newoff; 1297 proto = *nxtp; 1298 } 1299 } 1300 1301 /* 1302 * System control for IP6 1303 */ 1304 1305 u_char inet6ctlerrmap[PRC_NCMDS] = { 1306 0, 0, 0, 0, 1307 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1308 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1309 EMSGSIZE, EHOSTUNREACH, 0, 0, 1310 0, 0, 0, 0, 1311 ENOPROTOOPT 1312 }; 1313