ip6_input.c revision 1.39
1 /* $NetBSD: ip6_input.c,v 1.39 2001/03/21 19:12:56 itojun Exp $ */ 2 /* $KAME: ip6_input.c,v 1.183 2001/03/01 15:15:23 itojun 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_inet.h" 69 #include "opt_ipsec.h" 70 #include "opt_pfil_hooks.h" 71 72 #include <sys/param.h> 73 #include <sys/systm.h> 74 #include <sys/malloc.h> 75 #include <sys/mbuf.h> 76 #include <sys/domain.h> 77 #include <sys/protosw.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/errno.h> 81 #include <sys/time.h> 82 #include <sys/kernel.h> 83 #include <sys/syslog.h> 84 #include <sys/proc.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 #ifdef PFIL_HOOKS 92 #include <net/pfil.h> 93 #endif 94 95 #include <netinet/in.h> 96 #include <netinet/in_systm.h> 97 #ifdef INET 98 #include <netinet/ip.h> 99 #include <netinet/ip_icmp.h> 100 #endif /*INET*/ 101 #include <netinet/ip6.h> 102 #include <netinet6/in6_var.h> 103 #include <netinet6/ip6_var.h> 104 #include <netinet6/in6_pcb.h> 105 #include <netinet/icmp6.h> 106 #include <netinet6/in6_ifattach.h> 107 #include <netinet6/nd6.h> 108 #include <netinet6/in6_prefix.h> 109 110 #ifdef IPSEC 111 #include <netinet6/ipsec.h> 112 #endif 113 114 #include <netinet6/ip6protosw.h> 115 116 /* we need it for NLOOP. */ 117 #include "loop.h" 118 #include "faith.h" 119 120 #include "gif.h" 121 #include "bpfilter.h" 122 123 #include <net/net_osdep.h> 124 125 extern struct domain inet6domain; 126 127 u_char ip6_protox[IPPROTO_MAX]; 128 static int ip6qmaxlen = IFQ_MAXLEN; 129 struct in6_ifaddr *in6_ifaddr; 130 struct ifqueue ip6intrq; 131 132 extern struct ifnet loif[NLOOP]; 133 int ip6_forward_srcrt; /* XXX */ 134 int ip6_sourcecheck; /* XXX */ 135 int ip6_sourcecheck_interval; /* XXX */ 136 137 #ifdef PFIL_HOOKS 138 struct pfil_head inet6_pfil_hook; 139 #endif 140 141 struct ip6stat ip6stat; 142 143 static void ip6_init2 __P((void *)); 144 145 static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *)); 146 147 /* 148 * IP6 initialization: fill in IP6 protocol switch table. 149 * All protocols not implemented in kernel go to raw IP6 protocol handler. 150 */ 151 void 152 ip6_init() 153 { 154 struct ip6protosw *pr; 155 int i; 156 struct timeval tv; 157 158 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 159 if (pr == 0) 160 panic("ip6_init"); 161 for (i = 0; i < IPPROTO_MAX; i++) 162 ip6_protox[i] = pr - inet6sw; 163 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 164 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 165 if (pr->pr_domain->dom_family == PF_INET6 && 166 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 167 ip6_protox[pr->pr_protocol] = pr - inet6sw; 168 ip6intrq.ifq_maxlen = ip6qmaxlen; 169 nd6_init(); 170 frag6_init(); 171 /* 172 * in many cases, random() here does NOT return random number 173 * as initialization during bootstrap time occur in fixed order. 174 */ 175 microtime(&tv); 176 ip6_flow_seq = random() ^ tv.tv_usec; 177 178 ip6_init2((void *)0); 179 180 #ifdef PFIL_HOOKS 181 /* Register our Packet Filter hook. */ 182 inet6_pfil_hook.ph_type = PFIL_TYPE_AF; 183 inet6_pfil_hook.ph_af = AF_INET6; 184 i = pfil_head_register(&inet6_pfil_hook); 185 if (i != 0) 186 printf("ip6_init: WARNING: unable to register pfil hook, " 187 "error %d\n", i); 188 #endif /* PFIL_HOOKS */ 189 } 190 191 static void 192 ip6_init2(dummy) 193 void *dummy; 194 { 195 /* 196 * to route local address of p2p link to loopback, 197 * assign loopback address first. 198 */ 199 in6_ifattach(&loif[0], NULL); 200 201 /* nd6_timer_init */ 202 callout_init(&nd6_timer_ch); 203 callout_reset(&nd6_timer_ch, hz, nd6_timer, NULL); 204 /* router renumbering prefix list maintenance */ 205 callout_init(&in6_rr_timer_ch); 206 callout_reset(&in6_rr_timer_ch, hz, in6_rr_timer, NULL); 207 } 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; 240 241 #ifdef IPSEC 242 /* 243 * should the inner packet be considered authentic? 244 * see comment in ah4_input(). 245 */ 246 if (m) { 247 m->m_flags &= ~M_AUTHIPHDR; 248 m->m_flags &= ~M_AUTHIPDGM; 249 } 250 #endif 251 252 /* 253 * mbuf statistics by kazu 254 */ 255 if (m->m_flags & M_EXT) { 256 if (m->m_next) 257 ip6stat.ip6s_mext2m++; 258 else 259 ip6stat.ip6s_mext1++; 260 } else { 261 if (m->m_next) { 262 if (m->m_flags & M_LOOP) { 263 ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/ 264 } else if (m->m_pkthdr.rcvif->if_index <= 31) 265 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 266 else 267 ip6stat.ip6s_m2m[0]++; 268 } else 269 ip6stat.ip6s_m1++; 270 } 271 272 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 273 ip6stat.ip6s_total++; 274 275 #ifndef PULLDOWN_TEST 276 /* XXX is the line really necessary? */ 277 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/); 278 #endif 279 280 if (m->m_len < sizeof(struct ip6_hdr)) { 281 struct ifnet *inifp; 282 inifp = m->m_pkthdr.rcvif; 283 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 284 ip6stat.ip6s_toosmall++; 285 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 286 return; 287 } 288 } 289 290 ip6 = mtod(m, struct ip6_hdr *); 291 292 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 293 ip6stat.ip6s_badvers++; 294 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 295 goto bad; 296 } 297 298 #ifdef PFIL_HOOKS 299 /* 300 * Run through list of hooks for input packets. If there are any 301 * filters which require that additional packets in the flow are 302 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 303 * Note that filters must _never_ set this flag, as another filter 304 * in the list may have previously cleared it. 305 */ 306 /* 307 * let ipfilter look at packet on the wire, 308 * not the decapsulated packet. 309 */ 310 #ifdef IPSEC 311 if (!ipsec_gethist(m, NULL)) 312 #else 313 if (1) 314 #endif 315 { 316 if (pfil_run_hooks(&inet6_pfil_hook, &m, m->m_pkthdr.rcvif, 317 PFIL_IN) != 0) 318 return; 319 if (m == NULL) 320 return; 321 ip6 = mtod(m, struct ip6_hdr *); 322 } 323 #endif /* PFIL_HOOKS */ 324 325 326 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 327 328 #ifdef ALTQ 329 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 330 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 331 /* packet is dropped by traffic conditioner */ 332 return; 333 } 334 #endif 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 * The following check is not documented in the spec. Malicious party 347 * may be able to use IPv4 mapped addr to confuse tcp/udp stack and 348 * bypass security checks (act as if it was from 127.0.0.1 by using 349 * IPv6 src ::ffff:127.0.0.1). Be cautious. 350 * 351 * This check chokes if we are in SIIT cloud. As none of BSDs support 352 * IPv4-less kernel compilation, we cannot support SIIT environment 353 * at all. So, it makes more sense for us to reject any malicious 354 * packets for non-SIIT environment, than try to do a partical support 355 * for SIIT environment. 356 */ 357 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 358 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 359 ip6stat.ip6s_badscope++; 360 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 361 goto bad; 362 } 363 #if 0 364 /* 365 * Reject packets with IPv4 compatible addresses (auto tunnel). 366 * 367 * The code forbids auto tunnel relay case in RFC1933 (the check is 368 * stronger than RFC1933). We may want to re-enable it if mech-xx 369 * is revised to forbid relaying case. 370 */ 371 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 372 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 373 ip6stat.ip6s_badscope++; 374 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 375 goto bad; 376 } 377 #endif 378 379 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 380 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 381 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 382 ours = 1; 383 deliverifp = m->m_pkthdr.rcvif; 384 goto hbhcheck; 385 } else { 386 ip6stat.ip6s_badscope++; 387 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 388 goto bad; 389 } 390 } 391 392 /* drop packets if interface ID portion is already filled */ 393 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 394 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src) && 395 ip6->ip6_src.s6_addr16[1]) { 396 ip6stat.ip6s_badscope++; 397 goto bad; 398 } 399 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst) && 400 ip6->ip6_dst.s6_addr16[1]) { 401 ip6stat.ip6s_badscope++; 402 goto bad; 403 } 404 } 405 406 #ifndef FAKE_LOOPBACK_IF 407 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) 408 #else 409 if (1) 410 #endif 411 { 412 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 413 ip6->ip6_src.s6_addr16[1] 414 = htons(m->m_pkthdr.rcvif->if_index); 415 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 416 ip6->ip6_dst.s6_addr16[1] 417 = htons(m->m_pkthdr.rcvif->if_index); 418 } 419 420 /* 421 * XXX we need this since we do not have "goto ours" hack route 422 * for some of our ifaddrs on loopback interface. 423 * we should correct it by changing in6_ifattach to install 424 * "goto ours" hack route. 425 */ 426 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) != 0) { 427 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 428 ours = 1; 429 deliverifp = m->m_pkthdr.rcvif; 430 goto hbhcheck; 431 } 432 } 433 434 /* 435 * Multicast check 436 */ 437 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 438 struct in6_multi *in6m = 0; 439 440 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 441 /* 442 * See if we belong to the destination multicast group on the 443 * arrival interface. 444 */ 445 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 446 if (in6m) 447 ours = 1; 448 else if (!ip6_mrouter) { 449 ip6stat.ip6s_notmember++; 450 ip6stat.ip6s_cantforward++; 451 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 452 goto bad; 453 } 454 deliverifp = m->m_pkthdr.rcvif; 455 goto hbhcheck; 456 } 457 458 /* 459 * Unicast check 460 */ 461 if (ip6_forward_rt.ro_rt != NULL && 462 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) != 0 && 463 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 464 &((struct sockaddr_in6 *)(&ip6_forward_rt.ro_dst))->sin6_addr)) 465 ip6stat.ip6s_forward_cachehit++; 466 else { 467 struct sockaddr_in6 *dst6; 468 469 if (ip6_forward_rt.ro_rt) { 470 /* route is down or destination is different */ 471 ip6stat.ip6s_forward_cachemiss++; 472 RTFREE(ip6_forward_rt.ro_rt); 473 ip6_forward_rt.ro_rt = 0; 474 } 475 476 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 477 dst6 = (struct sockaddr_in6 *)&ip6_forward_rt.ro_dst; 478 dst6->sin6_len = sizeof(struct sockaddr_in6); 479 dst6->sin6_family = AF_INET6; 480 dst6->sin6_addr = ip6->ip6_dst; 481 482 rtalloc((struct route *)&ip6_forward_rt); 483 } 484 485 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 486 487 /* 488 * Accept the packet if the forwarding interface to the destination 489 * according to the routing table is the loopback interface, 490 * unless the associated route has a gateway. 491 * Note that this approach causes to accept a packet if there is a 492 * route to the loopback interface for the destination of the packet. 493 * But we think it's even useful in some situations, e.g. when using 494 * a special daemon which wants to intercept the packet. 495 */ 496 if (ip6_forward_rt.ro_rt && 497 (ip6_forward_rt.ro_rt->rt_flags & 498 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 499 #if 0 500 /* 501 * The check below is redundant since the comparison of 502 * the destination and the key of the rtentry has 503 * already done through looking up the routing table. 504 */ 505 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 506 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) && 507 #endif 508 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 509 struct in6_ifaddr *ia6 = 510 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 511 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 512 m->m_flags |= M_ANYCAST6; 513 /* 514 * packets to a tentative, duplicated, or somehow invalid 515 * address must not be accepted. 516 */ 517 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 518 /* this address is ready */ 519 ours = 1; 520 deliverifp = ia6->ia_ifp; /* correct? */ 521 goto hbhcheck; 522 } else { 523 /* address is not ready, so discard the packet. */ 524 nd6log((LOG_INFO, 525 "ip6_input: packet to an unready address %s->%s\n", 526 ip6_sprintf(&ip6->ip6_src), 527 ip6_sprintf(&ip6->ip6_dst))); 528 529 goto bad; 530 } 531 } 532 533 /* 534 * FAITH(Firewall Aided Internet Translator) 535 */ 536 #if defined(NFAITH) && 0 < NFAITH 537 if (ip6_keepfaith) { 538 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 539 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 540 /* XXX do we need more sanity checks? */ 541 ours = 1; 542 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 543 goto hbhcheck; 544 } 545 } 546 #endif 547 548 #if 0 549 { 550 /* 551 * Last resort: check in6_ifaddr for incoming interface. 552 * The code is here until I update the "goto ours hack" code above 553 * working right. 554 */ 555 struct ifaddr *ifa; 556 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 557 ifa; 558 ifa = ifa->ifa_list.tqe_next) { 559 if (ifa->ifa_addr == NULL) 560 continue; /* just for safety */ 561 if (ifa->ifa_addr->sa_family != AF_INET6) 562 continue; 563 if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ip6->ip6_dst)) { 564 ours = 1; 565 deliverifp = ifa->ifa_ifp; 566 goto hbhcheck; 567 } 568 } 569 } 570 #endif 571 572 /* 573 * Now there is no reason to process the packet if it's not our own 574 * and we're not a router. 575 */ 576 if (!ip6_forwarding) { 577 ip6stat.ip6s_cantforward++; 578 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 579 goto bad; 580 } 581 582 hbhcheck: 583 /* 584 * Process Hop-by-Hop options header if it's contained. 585 * m may be modified in ip6_hopopts_input(). 586 * If a JumboPayload option is included, plen will also be modified. 587 */ 588 plen = (u_int32_t)ntohs(ip6->ip6_plen); 589 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 590 struct ip6_hbh *hbh; 591 592 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 593 #if 0 /*touches NULL pointer*/ 594 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 595 #endif 596 return; /* m have already been freed */ 597 } 598 599 /* adjust pointer */ 600 ip6 = mtod(m, struct ip6_hdr *); 601 602 /* 603 * if the payload length field is 0 and the next header field 604 * indicates Hop-by-Hop Options header, then a Jumbo Payload 605 * option MUST be included. 606 */ 607 if (ip6->ip6_plen == 0 && plen == 0) { 608 /* 609 * Note that if a valid jumbo payload option is 610 * contained, ip6_hoptops_input() must set a valid 611 * (non-zero) payload length to the variable plen. 612 */ 613 ip6stat.ip6s_badoptions++; 614 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 615 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 616 icmp6_error(m, ICMP6_PARAM_PROB, 617 ICMP6_PARAMPROB_HEADER, 618 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 619 return; 620 } 621 #ifndef PULLDOWN_TEST 622 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 623 hbh = (struct ip6_hbh *)(ip6 + 1); 624 #else 625 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 626 sizeof(struct ip6_hbh)); 627 if (hbh == NULL) { 628 ip6stat.ip6s_tooshort++; 629 return; 630 } 631 #endif 632 nxt = hbh->ip6h_nxt; 633 634 /* 635 * accept the packet if a router alert option is included 636 * and we act as an IPv6 router. 637 */ 638 if (rtalert != ~0 && ip6_forwarding) 639 ours = 1; 640 } else 641 nxt = ip6->ip6_nxt; 642 643 /* 644 * Check that the amount of data in the buffers 645 * is as at least much as the IPv6 header would have us expect. 646 * Trim mbufs if longer than we expect. 647 * Drop packet if shorter than we expect. 648 */ 649 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 650 ip6stat.ip6s_tooshort++; 651 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 652 goto bad; 653 } 654 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 655 if (m->m_len == m->m_pkthdr.len) { 656 m->m_len = sizeof(struct ip6_hdr) + plen; 657 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 658 } else 659 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 660 } 661 662 /* 663 * Forward if desirable. 664 */ 665 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 666 /* 667 * If we are acting as a multicast router, all 668 * incoming multicast packets are passed to the 669 * kernel-level multicast forwarding function. 670 * The packet is returned (relatively) intact; if 671 * ip6_mforward() returns a non-zero value, the packet 672 * must be discarded, else it may be accepted below. 673 */ 674 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 675 ip6stat.ip6s_cantforward++; 676 m_freem(m); 677 return; 678 } 679 if (!ours) { 680 m_freem(m); 681 return; 682 } 683 } else if (!ours) { 684 ip6_forward(m, 0); 685 return; 686 } 687 688 ip6 = mtod(m, struct ip6_hdr *); 689 690 /* 691 * Malicious party may be able to use IPv4 mapped addr to confuse 692 * tcp/udp stack and bypass security checks (act as if it was from 693 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 694 * 695 * For SIIT end node behavior, you may want to disable the check. 696 * However, you will become vulnerable to attacks using IPv4 mapped 697 * source. 698 */ 699 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 700 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 701 ip6stat.ip6s_badscope++; 702 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 703 goto bad; 704 } 705 706 /* 707 * Tell launch routine the next header 708 */ 709 #ifdef IFA_STATS 710 if (deliverifp != NULL) { 711 struct in6_ifaddr *ia6; 712 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 713 if (ia6) 714 ia6->ia_ifa.ifa_data.ifad_inbytes += m->m_pkthdr.len; 715 } 716 #endif 717 ip6stat.ip6s_delivered++; 718 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 719 nest = 0; 720 while (nxt != IPPROTO_DONE) { 721 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 722 ip6stat.ip6s_toomanyhdr++; 723 goto bad; 724 } 725 726 /* 727 * protection against faulty packet - there should be 728 * more sanity checks in header chain processing. 729 */ 730 if (m->m_pkthdr.len < off) { 731 ip6stat.ip6s_tooshort++; 732 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 733 goto bad; 734 } 735 736 #ifdef IPSEC 737 /* 738 * enforce IPsec policy checking if we are seeing last header. 739 * note that we do not visit this with protocols with pcb layer 740 * code - like udp/tcp/raw ip. 741 */ 742 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && 743 ipsec6_in_reject(m, NULL)) { 744 ipsec6stat.in_polvio++; 745 goto bad; 746 } 747 #endif 748 749 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 750 } 751 return; 752 bad: 753 m_freem(m); 754 } 755 756 /* 757 * Hop-by-Hop options header processing. If a valid jumbo payload option is 758 * included, the real payload length will be stored in plenp. 759 */ 760 static int 761 ip6_hopopts_input(plenp, rtalertp, mp, offp) 762 u_int32_t *plenp; 763 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 764 struct mbuf **mp; 765 int *offp; 766 { 767 struct mbuf *m = *mp; 768 int off = *offp, hbhlen; 769 struct ip6_hbh *hbh; 770 u_int8_t *opt; 771 772 /* validation of the length of the header */ 773 #ifndef PULLDOWN_TEST 774 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 775 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 776 hbhlen = (hbh->ip6h_len + 1) << 3; 777 778 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 779 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 780 #else 781 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 782 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 783 if (hbh == NULL) { 784 ip6stat.ip6s_tooshort++; 785 return -1; 786 } 787 hbhlen = (hbh->ip6h_len + 1) << 3; 788 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 789 hbhlen); 790 if (hbh == NULL) { 791 ip6stat.ip6s_tooshort++; 792 return -1; 793 } 794 #endif 795 off += hbhlen; 796 hbhlen -= sizeof(struct ip6_hbh); 797 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 798 799 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 800 hbhlen, rtalertp, plenp) < 0) 801 return(-1); 802 803 *offp = off; 804 *mp = m; 805 return(0); 806 } 807 808 /* 809 * Search header for all Hop-by-hop options and process each option. 810 * This function is separate from ip6_hopopts_input() in order to 811 * handle a case where the sending node itself process its hop-by-hop 812 * options header. In such a case, the function is called from ip6_output(). 813 */ 814 int 815 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 816 struct mbuf *m; 817 u_int8_t *opthead; 818 int hbhlen; 819 u_int32_t *rtalertp; 820 u_int32_t *plenp; 821 { 822 struct ip6_hdr *ip6; 823 int optlen = 0; 824 u_int8_t *opt = opthead; 825 u_int16_t rtalert_val; 826 u_int32_t jumboplen; 827 828 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 829 switch (*opt) { 830 case IP6OPT_PAD1: 831 optlen = 1; 832 break; 833 case IP6OPT_PADN: 834 if (hbhlen < IP6OPT_MINLEN) { 835 ip6stat.ip6s_toosmall++; 836 goto bad; 837 } 838 optlen = *(opt + 1) + 2; 839 break; 840 case IP6OPT_RTALERT: 841 /* XXX may need check for alignment */ 842 if (hbhlen < IP6OPT_RTALERT_LEN) { 843 ip6stat.ip6s_toosmall++; 844 goto bad; 845 } 846 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 847 /* XXX: should we discard the packet? */ 848 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 849 *(opt + 1)); 850 } 851 optlen = IP6OPT_RTALERT_LEN; 852 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 853 *rtalertp = ntohs(rtalert_val); 854 break; 855 case IP6OPT_JUMBO: 856 /* XXX may need check for alignment */ 857 if (hbhlen < IP6OPT_JUMBO_LEN) { 858 ip6stat.ip6s_toosmall++; 859 goto bad; 860 } 861 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 862 /* XXX: should we discard the packet? */ 863 log(LOG_ERR, "length of jumbopayload opt " 864 "is inconsistent(%d)\n", 865 *(opt + 1)); 866 } 867 optlen = IP6OPT_JUMBO_LEN; 868 869 /* 870 * IPv6 packets that have non 0 payload length 871 * must not contain a jumbo payload option. 872 */ 873 ip6 = mtod(m, struct ip6_hdr *); 874 if (ip6->ip6_plen) { 875 ip6stat.ip6s_badoptions++; 876 icmp6_error(m, ICMP6_PARAM_PROB, 877 ICMP6_PARAMPROB_HEADER, 878 sizeof(struct ip6_hdr) + 879 sizeof(struct ip6_hbh) + 880 opt - opthead); 881 return(-1); 882 } 883 884 /* 885 * We may see jumbolen in unaligned location, so 886 * we'd need to perform bcopy(). 887 */ 888 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 889 jumboplen = (u_int32_t)htonl(jumboplen); 890 891 #if 1 892 /* 893 * if there are multiple jumbo payload options, 894 * *plenp will be non-zero and the packet will be 895 * rejected. 896 * the behavior may need some debate in ipngwg - 897 * multiple options does not make sense, however, 898 * there's no explicit mention in specification. 899 */ 900 if (*plenp != 0) { 901 ip6stat.ip6s_badoptions++; 902 icmp6_error(m, ICMP6_PARAM_PROB, 903 ICMP6_PARAMPROB_HEADER, 904 sizeof(struct ip6_hdr) + 905 sizeof(struct ip6_hbh) + 906 opt + 2 - opthead); 907 return(-1); 908 } 909 #endif 910 911 /* 912 * jumbo payload length must be larger than 65535. 913 */ 914 if (jumboplen <= IPV6_MAXPACKET) { 915 ip6stat.ip6s_badoptions++; 916 icmp6_error(m, ICMP6_PARAM_PROB, 917 ICMP6_PARAMPROB_HEADER, 918 sizeof(struct ip6_hdr) + 919 sizeof(struct ip6_hbh) + 920 opt + 2 - opthead); 921 return(-1); 922 } 923 *plenp = jumboplen; 924 925 break; 926 default: /* unknown option */ 927 if (hbhlen < IP6OPT_MINLEN) { 928 ip6stat.ip6s_toosmall++; 929 goto bad; 930 } 931 if ((optlen = ip6_unknown_opt(opt, m, 932 sizeof(struct ip6_hdr) + 933 sizeof(struct ip6_hbh) + 934 opt - opthead)) == -1) 935 return(-1); 936 optlen += 2; 937 break; 938 } 939 } 940 941 return(0); 942 943 bad: 944 m_freem(m); 945 return(-1); 946 } 947 948 /* 949 * Unknown option processing. 950 * The third argument `off' is the offset from the IPv6 header to the option, 951 * which is necessary if the IPv6 header the and option header and IPv6 header 952 * is not continuous in order to return an ICMPv6 error. 953 */ 954 int 955 ip6_unknown_opt(optp, m, off) 956 u_int8_t *optp; 957 struct mbuf *m; 958 int off; 959 { 960 struct ip6_hdr *ip6; 961 962 switch (IP6OPT_TYPE(*optp)) { 963 case IP6OPT_TYPE_SKIP: /* ignore the option */ 964 return((int)*(optp + 1)); 965 case IP6OPT_TYPE_DISCARD: /* silently discard */ 966 m_freem(m); 967 return(-1); 968 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 969 ip6stat.ip6s_badoptions++; 970 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 971 return(-1); 972 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 973 ip6stat.ip6s_badoptions++; 974 ip6 = mtod(m, struct ip6_hdr *); 975 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 976 (m->m_flags & (M_BCAST|M_MCAST))) 977 m_freem(m); 978 else 979 icmp6_error(m, ICMP6_PARAM_PROB, 980 ICMP6_PARAMPROB_OPTION, off); 981 return(-1); 982 } 983 984 m_freem(m); /* XXX: NOTREACHED */ 985 return(-1); 986 } 987 988 /* 989 * Create the "control" list for this pcb. 990 * 991 * The routine will be called from upper layer handlers like tcp6_input(). 992 * Thus the routine assumes that the caller (tcp6_input) have already 993 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 994 * very first mbuf on the mbuf chain. 995 * We may want to add some infinite loop prevention or sanity checks for safety. 996 * (This applies only when you are using KAME mbuf chain restriction, i.e. 997 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 998 */ 999 void 1000 ip6_savecontrol(in6p, mp, ip6, m) 1001 struct in6pcb *in6p; 1002 struct mbuf **mp; 1003 struct ip6_hdr *ip6; 1004 struct mbuf *m; 1005 { 1006 struct proc *p = curproc; /* XXX */ 1007 int privileged; 1008 1009 privileged = 0; 1010 if (p && !suser(p->p_ucred, &p->p_acflag)) 1011 privileged++; 1012 1013 #ifdef SO_TIMESTAMP 1014 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 1015 struct timeval tv; 1016 1017 microtime(&tv); 1018 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1019 SCM_TIMESTAMP, SOL_SOCKET); 1020 if (*mp) 1021 mp = &(*mp)->m_next; 1022 } 1023 #endif 1024 if (in6p->in6p_flags & IN6P_RECVDSTADDR) { 1025 *mp = sbcreatecontrol((caddr_t) &ip6->ip6_dst, 1026 sizeof(struct in6_addr), IPV6_RECVDSTADDR, 1027 IPPROTO_IPV6); 1028 if (*mp) 1029 mp = &(*mp)->m_next; 1030 } 1031 1032 #ifdef noyet 1033 /* options were tossed above */ 1034 if (in6p->in6p_flags & IN6P_RECVOPTS) 1035 /* broken */ 1036 /* ip6_srcroute doesn't do what we want here, need to fix */ 1037 if (in6p->in6p_flags & IPV6P_RECVRETOPTS) 1038 /* broken */ 1039 #endif 1040 1041 /* RFC 2292 sec. 5 */ 1042 if ((in6p->in6p_flags & IN6P_PKTINFO) != 0) { 1043 struct in6_pktinfo pi6; 1044 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1045 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 1046 pi6.ipi6_addr.s6_addr16[1] = 0; 1047 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 1048 ? m->m_pkthdr.rcvif->if_index 1049 : 0; 1050 *mp = sbcreatecontrol((caddr_t) &pi6, 1051 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 1052 IPPROTO_IPV6); 1053 if (*mp) 1054 mp = &(*mp)->m_next; 1055 } 1056 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 1057 int hlim = ip6->ip6_hlim & 0xff; 1058 *mp = sbcreatecontrol((caddr_t) &hlim, 1059 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 1060 if (*mp) 1061 mp = &(*mp)->m_next; 1062 } 1063 /* IN6P_NEXTHOP - for outgoing packet only */ 1064 1065 /* 1066 * IPV6_HOPOPTS socket option. We require super-user privilege 1067 * for the option, but it might be too strict, since there might 1068 * be some hop-by-hop options which can be returned to normal user. 1069 * See RFC 2292 section 6. 1070 */ 1071 if ((in6p->in6p_flags & IN6P_HOPOPTS) != 0 && privileged) { 1072 /* 1073 * Check if a hop-by-hop options header is contatined in the 1074 * received packet, and if so, store the options as ancillary 1075 * data. Note that a hop-by-hop options header must be 1076 * just after the IPv6 header, which fact is assured through 1077 * the IPv6 input processing. 1078 */ 1079 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1080 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1081 struct ip6_hbh *hbh; 1082 int hbhlen; 1083 1084 #ifndef PULLDOWN_TEST 1085 hbh = (struct ip6_hbh *)(ip6 + 1); 1086 hbhlen = (hbh->ip6h_len + 1) << 3; 1087 #else 1088 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1089 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1090 if (hbh == NULL) { 1091 ip6stat.ip6s_tooshort++; 1092 return; 1093 } 1094 hbhlen = (hbh->ip6h_len + 1) << 3; 1095 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1096 sizeof(struct ip6_hdr), hbhlen); 1097 if (hbh == NULL) { 1098 ip6stat.ip6s_tooshort++; 1099 return; 1100 } 1101 #endif 1102 1103 /* 1104 * XXX: We copy whole the header even if a jumbo 1105 * payload option is included, which option is to 1106 * be removed before returning in the RFC 2292. 1107 * But it's too painful operation... 1108 */ 1109 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1110 IPV6_HOPOPTS, IPPROTO_IPV6); 1111 if (*mp) 1112 mp = &(*mp)->m_next; 1113 } 1114 } 1115 1116 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1117 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 1118 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1119 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 1120 1121 /* 1122 * Search for destination options headers or routing 1123 * header(s) through the header chain, and stores each 1124 * header as ancillary data. 1125 * Note that the order of the headers remains in 1126 * the chain of ancillary data. 1127 */ 1128 while (1) { /* is explicit loop prevention necessary? */ 1129 struct ip6_ext *ip6e; 1130 int elen; 1131 1132 #ifndef PULLDOWN_TEST 1133 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1134 if (nxt == IPPROTO_AH) 1135 elen = (ip6e->ip6e_len + 2) << 2; 1136 else 1137 elen = (ip6e->ip6e_len + 1) << 3; 1138 #else 1139 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, 1140 sizeof(struct ip6_ext)); 1141 if (ip6e == NULL) { 1142 ip6stat.ip6s_tooshort++; 1143 return; 1144 } 1145 if (nxt == IPPROTO_AH) 1146 elen = (ip6e->ip6e_len + 2) << 2; 1147 else 1148 elen = (ip6e->ip6e_len + 1) << 3; 1149 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, elen); 1150 if (ip6e == NULL) { 1151 ip6stat.ip6s_tooshort++; 1152 return; 1153 } 1154 #endif 1155 1156 switch (nxt) { 1157 case IPPROTO_DSTOPTS: 1158 if (!in6p->in6p_flags & IN6P_DSTOPTS) 1159 break; 1160 1161 /* 1162 * We also require super-user privilege for 1163 * the option. 1164 * See the comments on IN6_HOPOPTS. 1165 */ 1166 if (!privileged) 1167 break; 1168 1169 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1170 IPV6_DSTOPTS, 1171 IPPROTO_IPV6); 1172 if (*mp) 1173 mp = &(*mp)->m_next; 1174 break; 1175 1176 case IPPROTO_ROUTING: 1177 if (!in6p->in6p_flags & IN6P_RTHDR) 1178 break; 1179 1180 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1181 IPV6_RTHDR, 1182 IPPROTO_IPV6); 1183 if (*mp) 1184 mp = &(*mp)->m_next; 1185 break; 1186 1187 case IPPROTO_UDP: 1188 case IPPROTO_TCP: 1189 case IPPROTO_ICMPV6: 1190 default: 1191 /* 1192 * stop search if we encounter an upper 1193 * layer protocol headers. 1194 */ 1195 goto loopend; 1196 1197 case IPPROTO_HOPOPTS: 1198 case IPPROTO_AH: /* is it possible? */ 1199 break; 1200 } 1201 1202 /* proceed with the next header. */ 1203 off += elen; 1204 nxt = ip6e->ip6e_nxt; 1205 } 1206 loopend: 1207 ; 1208 } 1209 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1210 /* to be done */ 1211 } 1212 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 1213 /* to be done */ 1214 } 1215 /* IN6P_RTHDR - to be done */ 1216 1217 } 1218 1219 /* 1220 * Get pointer to the previous header followed by the header 1221 * currently processed. 1222 * XXX: This function supposes that 1223 * M includes all headers, 1224 * the next header field and the header length field of each header 1225 * are valid, and 1226 * the sum of each header length equals to OFF. 1227 * Because of these assumptions, this function must be called very 1228 * carefully. Moreover, it will not be used in the near future when 1229 * we develop `neater' mechanism to process extension headers. 1230 */ 1231 char * 1232 ip6_get_prevhdr(m, off) 1233 struct mbuf *m; 1234 int off; 1235 { 1236 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1237 1238 if (off == sizeof(struct ip6_hdr)) 1239 return(&ip6->ip6_nxt); 1240 else { 1241 int len, nxt; 1242 struct ip6_ext *ip6e = NULL; 1243 1244 nxt = ip6->ip6_nxt; 1245 len = sizeof(struct ip6_hdr); 1246 while (len < off) { 1247 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1248 1249 switch (nxt) { 1250 case IPPROTO_FRAGMENT: 1251 len += sizeof(struct ip6_frag); 1252 break; 1253 case IPPROTO_AH: 1254 len += (ip6e->ip6e_len + 2) << 2; 1255 break; 1256 default: 1257 len += (ip6e->ip6e_len + 1) << 3; 1258 break; 1259 } 1260 nxt = ip6e->ip6e_nxt; 1261 } 1262 if (ip6e) 1263 return(&ip6e->ip6e_nxt); 1264 else 1265 return NULL; 1266 } 1267 } 1268 1269 /* 1270 * get next header offset. m will be retained. 1271 */ 1272 int 1273 ip6_nexthdr(m, off, proto, nxtp) 1274 struct mbuf *m; 1275 int off; 1276 int proto; 1277 int *nxtp; 1278 { 1279 struct ip6_hdr ip6; 1280 struct ip6_ext ip6e; 1281 struct ip6_frag fh; 1282 1283 /* just in case */ 1284 if (m == NULL) 1285 panic("ip6_nexthdr: m == NULL"); 1286 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1287 return -1; 1288 1289 switch (proto) { 1290 case IPPROTO_IPV6: 1291 if (m->m_pkthdr.len < off + sizeof(ip6)) 1292 return -1; 1293 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1294 if (nxtp) 1295 *nxtp = ip6.ip6_nxt; 1296 off += sizeof(ip6); 1297 return off; 1298 1299 case IPPROTO_FRAGMENT: 1300 /* 1301 * terminate parsing if it is not the first fragment, 1302 * it does not make sense to parse through it. 1303 */ 1304 if (m->m_pkthdr.len < off + sizeof(fh)) 1305 return -1; 1306 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1307 if ((ntohs(fh.ip6f_offlg) & IP6F_OFF_MASK) != 0) 1308 return -1; 1309 if (nxtp) 1310 *nxtp = fh.ip6f_nxt; 1311 off += sizeof(struct ip6_frag); 1312 return off; 1313 1314 case IPPROTO_AH: 1315 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1316 return -1; 1317 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1318 if (nxtp) 1319 *nxtp = ip6e.ip6e_nxt; 1320 off += (ip6e.ip6e_len + 2) << 2; 1321 return off; 1322 1323 case IPPROTO_HOPOPTS: 1324 case IPPROTO_ROUTING: 1325 case IPPROTO_DSTOPTS: 1326 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1327 return -1; 1328 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1329 if (nxtp) 1330 *nxtp = ip6e.ip6e_nxt; 1331 off += (ip6e.ip6e_len + 1) << 3; 1332 return off; 1333 1334 case IPPROTO_NONE: 1335 case IPPROTO_ESP: 1336 case IPPROTO_IPCOMP: 1337 /* give up */ 1338 return -1; 1339 1340 default: 1341 return -1; 1342 } 1343 1344 return -1; 1345 } 1346 1347 /* 1348 * get offset for the last header in the chain. m will be kept untainted. 1349 */ 1350 int 1351 ip6_lasthdr(m, off, proto, nxtp) 1352 struct mbuf *m; 1353 int off; 1354 int proto; 1355 int *nxtp; 1356 { 1357 int newoff; 1358 int nxt; 1359 1360 if (!nxtp) { 1361 nxt = -1; 1362 nxtp = &nxt; 1363 } 1364 while (1) { 1365 newoff = ip6_nexthdr(m, off, proto, nxtp); 1366 if (newoff < 0) 1367 return off; 1368 else if (newoff < off) 1369 return -1; /* invalid */ 1370 else if (newoff == off) 1371 return newoff; 1372 1373 off = newoff; 1374 proto = *nxtp; 1375 } 1376 } 1377 1378 /* 1379 * System control for IP6 1380 */ 1381 1382 u_char inet6ctlerrmap[PRC_NCMDS] = { 1383 0, 0, 0, 0, 1384 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1385 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1386 EMSGSIZE, EHOSTUNREACH, 0, 0, 1387 0, 0, 0, 0, 1388 ENOPROTOOPT 1389 }; 1390 1391 #include <uvm/uvm_extern.h> 1392 #include <sys/sysctl.h> 1393 1394 int 1395 ip6_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1396 int *name; 1397 u_int namelen; 1398 void *oldp; 1399 size_t *oldlenp; 1400 void *newp; 1401 size_t newlen; 1402 { 1403 int old, error; 1404 1405 /* All sysctl names at this level are terminal. */ 1406 if (namelen != 1) 1407 return ENOTDIR; 1408 1409 switch (name[0]) { 1410 1411 case IPV6CTL_FORWARDING: 1412 return sysctl_int(oldp, oldlenp, newp, newlen, 1413 &ip6_forwarding); 1414 case IPV6CTL_SENDREDIRECTS: 1415 return sysctl_int(oldp, oldlenp, newp, newlen, 1416 &ip6_sendredirects); 1417 case IPV6CTL_DEFHLIM: 1418 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_defhlim); 1419 case IPV6CTL_MAXFRAGPACKETS: 1420 return sysctl_int(oldp, oldlenp, newp, newlen, 1421 &ip6_maxfragpackets); 1422 case IPV6CTL_ACCEPT_RTADV: 1423 return sysctl_int(oldp, oldlenp, newp, newlen, 1424 &ip6_accept_rtadv); 1425 case IPV6CTL_KEEPFAITH: 1426 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_keepfaith); 1427 case IPV6CTL_LOG_INTERVAL: 1428 return sysctl_int(oldp, oldlenp, newp, newlen, 1429 &ip6_log_interval); 1430 case IPV6CTL_HDRNESTLIMIT: 1431 return sysctl_int(oldp, oldlenp, newp, newlen, 1432 &ip6_hdrnestlimit); 1433 case IPV6CTL_DAD_COUNT: 1434 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_dad_count); 1435 case IPV6CTL_AUTO_FLOWLABEL: 1436 return sysctl_int(oldp, oldlenp, newp, newlen, 1437 &ip6_auto_flowlabel); 1438 case IPV6CTL_DEFMCASTHLIM: 1439 return sysctl_int(oldp, oldlenp, newp, newlen, 1440 &ip6_defmcasthlim); 1441 case IPV6CTL_GIF_HLIM: 1442 return sysctl_int(oldp, oldlenp, newp, newlen, 1443 &ip6_gif_hlim); 1444 case IPV6CTL_KAME_VERSION: 1445 return sysctl_rdstring(oldp, oldlenp, newp, __KAME_VERSION); 1446 case IPV6CTL_USE_DEPRECATED: 1447 return sysctl_int(oldp, oldlenp, newp, newlen, 1448 &ip6_use_deprecated); 1449 case IPV6CTL_RR_PRUNE: 1450 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_rr_prune); 1451 #ifndef INET6_BINDV6ONLY 1452 case IPV6CTL_BINDV6ONLY: 1453 return sysctl_int(oldp, oldlenp, newp, newlen, 1454 &ip6_bindv6only); 1455 #endif 1456 case IPV6CTL_ANONPORTMIN: 1457 old = ip6_anonportmin; 1458 error = sysctl_int(oldp, oldlenp, newp, newlen, 1459 &ip6_anonportmin); 1460 if (ip6_anonportmin >= ip6_anonportmax || ip6_anonportmin < 0 || 1461 ip6_anonportmin > 65535 1462 #ifndef IPNOPRIVPORTS 1463 || ip6_anonportmin < IPV6PORT_RESERVED 1464 #endif 1465 ) { 1466 ip6_anonportmin = old; 1467 return (EINVAL); 1468 } 1469 return (error); 1470 case IPV6CTL_ANONPORTMAX: 1471 old = ip6_anonportmax; 1472 error = sysctl_int(oldp, oldlenp, newp, newlen, 1473 &ip6_anonportmax); 1474 if (ip6_anonportmin >= ip6_anonportmax || ip6_anonportmax < 0 || 1475 ip6_anonportmax > 65535 1476 #ifndef IPNOPRIVPORTS 1477 || ip6_anonportmax < IPV6PORT_RESERVED 1478 #endif 1479 ) { 1480 ip6_anonportmax = old; 1481 return (EINVAL); 1482 } 1483 return (error); 1484 #ifndef IPNOPRIVPORTS 1485 case IPV6CTL_LOWPORTMIN: 1486 old = ip6_lowportmin; 1487 error = sysctl_int(oldp, oldlenp, newp, newlen, 1488 &ip6_lowportmin); 1489 if (ip6_lowportmin >= ip6_lowportmax || 1490 ip6_lowportmin > IPV6PORT_RESERVEDMAX || 1491 ip6_lowportmin < IPV6PORT_RESERVEDMIN) { 1492 ip6_lowportmin = old; 1493 return (EINVAL); 1494 } 1495 return (error); 1496 case IPV6CTL_LOWPORTMAX: 1497 old = ip6_lowportmax; 1498 error = sysctl_int(oldp, oldlenp, newp, newlen, 1499 &ip6_lowportmax); 1500 if (ip6_lowportmin >= ip6_lowportmax || 1501 ip6_lowportmax > IPV6PORT_RESERVEDMAX || 1502 ip6_lowportmax < IPV6PORT_RESERVEDMIN) { 1503 ip6_lowportmax = old; 1504 return (EINVAL); 1505 } 1506 return (error); 1507 #endif 1508 default: 1509 return EOPNOTSUPP; 1510 } 1511 /* NOTREACHED */ 1512 } 1513
Indexes created Mon Sep 22 21:09:42 GMT 2025