ip6_input.c revision 1.38
1 /* $NetBSD: ip6_input.c,v 1.38 2001/03/16 12:22:34 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 if (pfil_run_hooks(&inet6_pfil_hook, &m, m->m_pkthdr.rcvif, 307 PFIL_IN) != 0) 308 return; 309 if (m == NULL) 310 return; 311 ip6 = mtod(m, struct ip6_hdr *); 312 #endif /* PFIL_HOOKS */ 313 314 315 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 316 317 #ifdef ALTQ 318 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 319 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 320 /* packet is dropped by traffic conditioner */ 321 return; 322 } 323 #endif 324 325 /* 326 * Scope check 327 */ 328 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 329 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 330 ip6stat.ip6s_badscope++; 331 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 332 goto bad; 333 } 334 /* 335 * The following check is not documented in the spec. Malicious party 336 * may be able to use IPv4 mapped addr to confuse tcp/udp stack and 337 * bypass security checks (act as if it was from 127.0.0.1 by using 338 * IPv6 src ::ffff:127.0.0.1). Be cautious. 339 * 340 * This check chokes if we are in SIIT cloud. As none of BSDs support 341 * IPv4-less kernel compilation, we cannot support SIIT environment 342 * at all. So, it makes more sense for us to reject any malicious 343 * packets for non-SIIT environment, than try to do a partical support 344 * for SIIT environment. 345 */ 346 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 347 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 348 ip6stat.ip6s_badscope++; 349 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 350 goto bad; 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 367 368 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 369 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 370 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 371 ours = 1; 372 deliverifp = m->m_pkthdr.rcvif; 373 goto hbhcheck; 374 } else { 375 ip6stat.ip6s_badscope++; 376 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 377 goto bad; 378 } 379 } 380 381 /* drop packets if interface ID portion is already filled */ 382 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 383 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src) && 384 ip6->ip6_src.s6_addr16[1]) { 385 ip6stat.ip6s_badscope++; 386 goto bad; 387 } 388 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst) && 389 ip6->ip6_dst.s6_addr16[1]) { 390 ip6stat.ip6s_badscope++; 391 goto bad; 392 } 393 } 394 395 #ifndef FAKE_LOOPBACK_IF 396 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) 397 #else 398 if (1) 399 #endif 400 { 401 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 402 ip6->ip6_src.s6_addr16[1] 403 = htons(m->m_pkthdr.rcvif->if_index); 404 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 405 ip6->ip6_dst.s6_addr16[1] 406 = htons(m->m_pkthdr.rcvif->if_index); 407 } 408 409 /* 410 * XXX we need this since we do not have "goto ours" hack route 411 * for some of our ifaddrs on loopback interface. 412 * we should correct it by changing in6_ifattach to install 413 * "goto ours" hack route. 414 */ 415 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) != 0) { 416 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 417 ours = 1; 418 deliverifp = m->m_pkthdr.rcvif; 419 goto hbhcheck; 420 } 421 } 422 423 /* 424 * Multicast check 425 */ 426 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 427 struct in6_multi *in6m = 0; 428 429 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 430 /* 431 * See if we belong to the destination multicast group on the 432 * arrival interface. 433 */ 434 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 435 if (in6m) 436 ours = 1; 437 else if (!ip6_mrouter) { 438 ip6stat.ip6s_notmember++; 439 ip6stat.ip6s_cantforward++; 440 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 441 goto bad; 442 } 443 deliverifp = m->m_pkthdr.rcvif; 444 goto hbhcheck; 445 } 446 447 /* 448 * Unicast check 449 */ 450 if (ip6_forward_rt.ro_rt != NULL && 451 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) != 0 && 452 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 453 &((struct sockaddr_in6 *)(&ip6_forward_rt.ro_dst))->sin6_addr)) 454 ip6stat.ip6s_forward_cachehit++; 455 else { 456 struct sockaddr_in6 *dst6; 457 458 if (ip6_forward_rt.ro_rt) { 459 /* route is down or destination is different */ 460 ip6stat.ip6s_forward_cachemiss++; 461 RTFREE(ip6_forward_rt.ro_rt); 462 ip6_forward_rt.ro_rt = 0; 463 } 464 465 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 466 dst6 = (struct sockaddr_in6 *)&ip6_forward_rt.ro_dst; 467 dst6->sin6_len = sizeof(struct sockaddr_in6); 468 dst6->sin6_family = AF_INET6; 469 dst6->sin6_addr = ip6->ip6_dst; 470 471 rtalloc((struct route *)&ip6_forward_rt); 472 } 473 474 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 475 476 /* 477 * Accept the packet if the forwarding interface to the destination 478 * according to the routing table is the loopback interface, 479 * unless the associated route has a gateway. 480 * Note that this approach causes to accept a packet if there is a 481 * route to the loopback interface for the destination of the packet. 482 * But we think it's even useful in some situations, e.g. when using 483 * a special daemon which wants to intercept the packet. 484 */ 485 if (ip6_forward_rt.ro_rt && 486 (ip6_forward_rt.ro_rt->rt_flags & 487 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 488 #if 0 489 /* 490 * The check below is redundant since the comparison of 491 * the destination and the key of the rtentry has 492 * already done through looking up the routing table. 493 */ 494 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 495 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) && 496 #endif 497 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 498 struct in6_ifaddr *ia6 = 499 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 500 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 501 m->m_flags |= M_ANYCAST6; 502 /* 503 * packets to a tentative, duplicated, or somehow invalid 504 * address must not be accepted. 505 */ 506 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 507 /* this address is ready */ 508 ours = 1; 509 deliverifp = ia6->ia_ifp; /* correct? */ 510 goto hbhcheck; 511 } else { 512 /* address is not ready, so discard the packet. */ 513 nd6log((LOG_INFO, 514 "ip6_input: packet to an unready address %s->%s\n", 515 ip6_sprintf(&ip6->ip6_src), 516 ip6_sprintf(&ip6->ip6_dst))); 517 518 goto bad; 519 } 520 } 521 522 /* 523 * FAITH(Firewall Aided Internet Translator) 524 */ 525 #if defined(NFAITH) && 0 < NFAITH 526 if (ip6_keepfaith) { 527 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 528 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 529 /* XXX do we need more sanity checks? */ 530 ours = 1; 531 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 532 goto hbhcheck; 533 } 534 } 535 #endif 536 537 #if 0 538 { 539 /* 540 * Last resort: check in6_ifaddr for incoming interface. 541 * The code is here until I update the "goto ours hack" code above 542 * working right. 543 */ 544 struct ifaddr *ifa; 545 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 546 ifa; 547 ifa = ifa->ifa_list.tqe_next) { 548 if (ifa->ifa_addr == NULL) 549 continue; /* just for safety */ 550 if (ifa->ifa_addr->sa_family != AF_INET6) 551 continue; 552 if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ip6->ip6_dst)) { 553 ours = 1; 554 deliverifp = ifa->ifa_ifp; 555 goto hbhcheck; 556 } 557 } 558 } 559 #endif 560 561 /* 562 * Now there is no reason to process the packet if it's not our own 563 * and we're not a router. 564 */ 565 if (!ip6_forwarding) { 566 ip6stat.ip6s_cantforward++; 567 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 568 goto bad; 569 } 570 571 hbhcheck: 572 /* 573 * Process Hop-by-Hop options header if it's contained. 574 * m may be modified in ip6_hopopts_input(). 575 * If a JumboPayload option is included, plen will also be modified. 576 */ 577 plen = (u_int32_t)ntohs(ip6->ip6_plen); 578 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 579 struct ip6_hbh *hbh; 580 581 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 582 #if 0 /*touches NULL pointer*/ 583 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 584 #endif 585 return; /* m have already been freed */ 586 } 587 588 /* adjust pointer */ 589 ip6 = mtod(m, struct ip6_hdr *); 590 591 /* 592 * if the payload length field is 0 and the next header field 593 * indicates Hop-by-Hop Options header, then a Jumbo Payload 594 * option MUST be included. 595 */ 596 if (ip6->ip6_plen == 0 && plen == 0) { 597 /* 598 * Note that if a valid jumbo payload option is 599 * contained, ip6_hoptops_input() must set a valid 600 * (non-zero) payload length to the variable plen. 601 */ 602 ip6stat.ip6s_badoptions++; 603 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 604 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 605 icmp6_error(m, ICMP6_PARAM_PROB, 606 ICMP6_PARAMPROB_HEADER, 607 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 608 return; 609 } 610 #ifndef PULLDOWN_TEST 611 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 612 hbh = (struct ip6_hbh *)(ip6 + 1); 613 #else 614 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 615 sizeof(struct ip6_hbh)); 616 if (hbh == NULL) { 617 ip6stat.ip6s_tooshort++; 618 return; 619 } 620 #endif 621 nxt = hbh->ip6h_nxt; 622 623 /* 624 * accept the packet if a router alert option is included 625 * and we act as an IPv6 router. 626 */ 627 if (rtalert != ~0 && ip6_forwarding) 628 ours = 1; 629 } else 630 nxt = ip6->ip6_nxt; 631 632 /* 633 * Check that the amount of data in the buffers 634 * is as at least much as the IPv6 header would have us expect. 635 * Trim mbufs if longer than we expect. 636 * Drop packet if shorter than we expect. 637 */ 638 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 639 ip6stat.ip6s_tooshort++; 640 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 641 goto bad; 642 } 643 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 644 if (m->m_len == m->m_pkthdr.len) { 645 m->m_len = sizeof(struct ip6_hdr) + plen; 646 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 647 } else 648 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 649 } 650 651 /* 652 * Forward if desirable. 653 */ 654 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 655 /* 656 * If we are acting as a multicast router, all 657 * incoming multicast packets are passed to the 658 * kernel-level multicast forwarding function. 659 * The packet is returned (relatively) intact; if 660 * ip6_mforward() returns a non-zero value, the packet 661 * must be discarded, else it may be accepted below. 662 */ 663 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 664 ip6stat.ip6s_cantforward++; 665 m_freem(m); 666 return; 667 } 668 if (!ours) { 669 m_freem(m); 670 return; 671 } 672 } else if (!ours) { 673 ip6_forward(m, 0); 674 return; 675 } 676 677 ip6 = mtod(m, struct ip6_hdr *); 678 679 /* 680 * Malicious party may be able to use IPv4 mapped addr to confuse 681 * tcp/udp stack and bypass security checks (act as if it was from 682 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 683 * 684 * For SIIT end node behavior, you may want to disable the check. 685 * However, you will become vulnerable to attacks using IPv4 mapped 686 * source. 687 */ 688 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 689 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 690 ip6stat.ip6s_badscope++; 691 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 692 goto bad; 693 } 694 695 /* 696 * Tell launch routine the next header 697 */ 698 #ifdef IFA_STATS 699 if (deliverifp != NULL) { 700 struct in6_ifaddr *ia6; 701 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 702 if (ia6) 703 ia6->ia_ifa.ifa_data.ifad_inbytes += m->m_pkthdr.len; 704 } 705 #endif 706 ip6stat.ip6s_delivered++; 707 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 708 nest = 0; 709 while (nxt != IPPROTO_DONE) { 710 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 711 ip6stat.ip6s_toomanyhdr++; 712 goto bad; 713 } 714 715 /* 716 * protection against faulty packet - there should be 717 * more sanity checks in header chain processing. 718 */ 719 if (m->m_pkthdr.len < off) { 720 ip6stat.ip6s_tooshort++; 721 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 722 goto bad; 723 } 724 725 #ifdef IPSEC 726 /* 727 * enforce IPsec policy checking if we are seeing last header. 728 * note that we do not visit this with protocols with pcb layer 729 * code - like udp/tcp/raw ip. 730 */ 731 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && 732 ipsec6_in_reject(m, NULL)) { 733 ipsec6stat.in_polvio++; 734 goto bad; 735 } 736 #endif 737 738 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 739 } 740 return; 741 bad: 742 m_freem(m); 743 } 744 745 /* 746 * Hop-by-Hop options header processing. If a valid jumbo payload option is 747 * included, the real payload length will be stored in plenp. 748 */ 749 static int 750 ip6_hopopts_input(plenp, rtalertp, mp, offp) 751 u_int32_t *plenp; 752 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 753 struct mbuf **mp; 754 int *offp; 755 { 756 struct mbuf *m = *mp; 757 int off = *offp, hbhlen; 758 struct ip6_hbh *hbh; 759 u_int8_t *opt; 760 761 /* validation of the length of the header */ 762 #ifndef PULLDOWN_TEST 763 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 764 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 765 hbhlen = (hbh->ip6h_len + 1) << 3; 766 767 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 768 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 769 #else 770 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 771 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 772 if (hbh == NULL) { 773 ip6stat.ip6s_tooshort++; 774 return -1; 775 } 776 hbhlen = (hbh->ip6h_len + 1) << 3; 777 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 778 hbhlen); 779 if (hbh == NULL) { 780 ip6stat.ip6s_tooshort++; 781 return -1; 782 } 783 #endif 784 off += hbhlen; 785 hbhlen -= sizeof(struct ip6_hbh); 786 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 787 788 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 789 hbhlen, rtalertp, plenp) < 0) 790 return(-1); 791 792 *offp = off; 793 *mp = m; 794 return(0); 795 } 796 797 /* 798 * Search header for all Hop-by-hop options and process each option. 799 * This function is separate from ip6_hopopts_input() in order to 800 * handle a case where the sending node itself process its hop-by-hop 801 * options header. In such a case, the function is called from ip6_output(). 802 */ 803 int 804 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 805 struct mbuf *m; 806 u_int8_t *opthead; 807 int hbhlen; 808 u_int32_t *rtalertp; 809 u_int32_t *plenp; 810 { 811 struct ip6_hdr *ip6; 812 int optlen = 0; 813 u_int8_t *opt = opthead; 814 u_int16_t rtalert_val; 815 u_int32_t jumboplen; 816 817 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 818 switch (*opt) { 819 case IP6OPT_PAD1: 820 optlen = 1; 821 break; 822 case IP6OPT_PADN: 823 if (hbhlen < IP6OPT_MINLEN) { 824 ip6stat.ip6s_toosmall++; 825 goto bad; 826 } 827 optlen = *(opt + 1) + 2; 828 break; 829 case IP6OPT_RTALERT: 830 /* XXX may need check for alignment */ 831 if (hbhlen < IP6OPT_RTALERT_LEN) { 832 ip6stat.ip6s_toosmall++; 833 goto bad; 834 } 835 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 836 /* XXX: should we discard the packet? */ 837 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 838 *(opt + 1)); 839 } 840 optlen = IP6OPT_RTALERT_LEN; 841 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 842 *rtalertp = ntohs(rtalert_val); 843 break; 844 case IP6OPT_JUMBO: 845 /* XXX may need check for alignment */ 846 if (hbhlen < IP6OPT_JUMBO_LEN) { 847 ip6stat.ip6s_toosmall++; 848 goto bad; 849 } 850 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 851 /* XXX: should we discard the packet? */ 852 log(LOG_ERR, "length of jumbopayload opt " 853 "is inconsistent(%d)\n", 854 *(opt + 1)); 855 } 856 optlen = IP6OPT_JUMBO_LEN; 857 858 /* 859 * IPv6 packets that have non 0 payload length 860 * must not contain a jumbo payload option. 861 */ 862 ip6 = mtod(m, struct ip6_hdr *); 863 if (ip6->ip6_plen) { 864 ip6stat.ip6s_badoptions++; 865 icmp6_error(m, ICMP6_PARAM_PROB, 866 ICMP6_PARAMPROB_HEADER, 867 sizeof(struct ip6_hdr) + 868 sizeof(struct ip6_hbh) + 869 opt - opthead); 870 return(-1); 871 } 872 873 /* 874 * We may see jumbolen in unaligned location, so 875 * we'd need to perform bcopy(). 876 */ 877 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 878 jumboplen = (u_int32_t)htonl(jumboplen); 879 880 #if 1 881 /* 882 * if there are multiple jumbo payload options, 883 * *plenp will be non-zero and the packet will be 884 * rejected. 885 * the behavior may need some debate in ipngwg - 886 * multiple options does not make sense, however, 887 * there's no explicit mention in specification. 888 */ 889 if (*plenp != 0) { 890 ip6stat.ip6s_badoptions++; 891 icmp6_error(m, ICMP6_PARAM_PROB, 892 ICMP6_PARAMPROB_HEADER, 893 sizeof(struct ip6_hdr) + 894 sizeof(struct ip6_hbh) + 895 opt + 2 - opthead); 896 return(-1); 897 } 898 #endif 899 900 /* 901 * jumbo payload length must be larger than 65535. 902 */ 903 if (jumboplen <= IPV6_MAXPACKET) { 904 ip6stat.ip6s_badoptions++; 905 icmp6_error(m, ICMP6_PARAM_PROB, 906 ICMP6_PARAMPROB_HEADER, 907 sizeof(struct ip6_hdr) + 908 sizeof(struct ip6_hbh) + 909 opt + 2 - opthead); 910 return(-1); 911 } 912 *plenp = jumboplen; 913 914 break; 915 default: /* unknown option */ 916 if (hbhlen < IP6OPT_MINLEN) { 917 ip6stat.ip6s_toosmall++; 918 goto bad; 919 } 920 if ((optlen = ip6_unknown_opt(opt, m, 921 sizeof(struct ip6_hdr) + 922 sizeof(struct ip6_hbh) + 923 opt - opthead)) == -1) 924 return(-1); 925 optlen += 2; 926 break; 927 } 928 } 929 930 return(0); 931 932 bad: 933 m_freem(m); 934 return(-1); 935 } 936 937 /* 938 * Unknown option processing. 939 * The third argument `off' is the offset from the IPv6 header to the option, 940 * which is necessary if the IPv6 header the and option header and IPv6 header 941 * is not continuous in order to return an ICMPv6 error. 942 */ 943 int 944 ip6_unknown_opt(optp, m, off) 945 u_int8_t *optp; 946 struct mbuf *m; 947 int off; 948 { 949 struct ip6_hdr *ip6; 950 951 switch (IP6OPT_TYPE(*optp)) { 952 case IP6OPT_TYPE_SKIP: /* ignore the option */ 953 return((int)*(optp + 1)); 954 case IP6OPT_TYPE_DISCARD: /* silently discard */ 955 m_freem(m); 956 return(-1); 957 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 958 ip6stat.ip6s_badoptions++; 959 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 960 return(-1); 961 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 962 ip6stat.ip6s_badoptions++; 963 ip6 = mtod(m, struct ip6_hdr *); 964 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 965 (m->m_flags & (M_BCAST|M_MCAST))) 966 m_freem(m); 967 else 968 icmp6_error(m, ICMP6_PARAM_PROB, 969 ICMP6_PARAMPROB_OPTION, off); 970 return(-1); 971 } 972 973 m_freem(m); /* XXX: NOTREACHED */ 974 return(-1); 975 } 976 977 /* 978 * Create the "control" list for this pcb. 979 * 980 * The routine will be called from upper layer handlers like tcp6_input(). 981 * Thus the routine assumes that the caller (tcp6_input) have already 982 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 983 * very first mbuf on the mbuf chain. 984 * We may want to add some infinite loop prevention or sanity checks for safety. 985 * (This applies only when you are using KAME mbuf chain restriction, i.e. 986 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 987 */ 988 void 989 ip6_savecontrol(in6p, mp, ip6, m) 990 struct in6pcb *in6p; 991 struct mbuf **mp; 992 struct ip6_hdr *ip6; 993 struct mbuf *m; 994 { 995 struct proc *p = curproc; /* XXX */ 996 int privileged; 997 998 privileged = 0; 999 if (p && !suser(p->p_ucred, &p->p_acflag)) 1000 privileged++; 1001 1002 #ifdef SO_TIMESTAMP 1003 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 1004 struct timeval tv; 1005 1006 microtime(&tv); 1007 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1008 SCM_TIMESTAMP, SOL_SOCKET); 1009 if (*mp) 1010 mp = &(*mp)->m_next; 1011 } 1012 #endif 1013 if (in6p->in6p_flags & IN6P_RECVDSTADDR) { 1014 *mp = sbcreatecontrol((caddr_t) &ip6->ip6_dst, 1015 sizeof(struct in6_addr), IPV6_RECVDSTADDR, 1016 IPPROTO_IPV6); 1017 if (*mp) 1018 mp = &(*mp)->m_next; 1019 } 1020 1021 #ifdef noyet 1022 /* options were tossed above */ 1023 if (in6p->in6p_flags & IN6P_RECVOPTS) 1024 /* broken */ 1025 /* ip6_srcroute doesn't do what we want here, need to fix */ 1026 if (in6p->in6p_flags & IPV6P_RECVRETOPTS) 1027 /* broken */ 1028 #endif 1029 1030 /* RFC 2292 sec. 5 */ 1031 if ((in6p->in6p_flags & IN6P_PKTINFO) != 0) { 1032 struct in6_pktinfo pi6; 1033 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1034 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 1035 pi6.ipi6_addr.s6_addr16[1] = 0; 1036 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 1037 ? m->m_pkthdr.rcvif->if_index 1038 : 0; 1039 *mp = sbcreatecontrol((caddr_t) &pi6, 1040 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 1041 IPPROTO_IPV6); 1042 if (*mp) 1043 mp = &(*mp)->m_next; 1044 } 1045 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 1046 int hlim = ip6->ip6_hlim & 0xff; 1047 *mp = sbcreatecontrol((caddr_t) &hlim, 1048 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 1049 if (*mp) 1050 mp = &(*mp)->m_next; 1051 } 1052 /* IN6P_NEXTHOP - for outgoing packet only */ 1053 1054 /* 1055 * IPV6_HOPOPTS socket option. We require super-user privilege 1056 * for the option, but it might be too strict, since there might 1057 * be some hop-by-hop options which can be returned to normal user. 1058 * See RFC 2292 section 6. 1059 */ 1060 if ((in6p->in6p_flags & IN6P_HOPOPTS) != 0 && privileged) { 1061 /* 1062 * Check if a hop-by-hop options header is contatined in the 1063 * received packet, and if so, store the options as ancillary 1064 * data. Note that a hop-by-hop options header must be 1065 * just after the IPv6 header, which fact is assured through 1066 * the IPv6 input processing. 1067 */ 1068 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1069 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1070 struct ip6_hbh *hbh; 1071 int hbhlen; 1072 1073 #ifndef PULLDOWN_TEST 1074 hbh = (struct ip6_hbh *)(ip6 + 1); 1075 hbhlen = (hbh->ip6h_len + 1) << 3; 1076 #else 1077 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1078 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1079 if (hbh == NULL) { 1080 ip6stat.ip6s_tooshort++; 1081 return; 1082 } 1083 hbhlen = (hbh->ip6h_len + 1) << 3; 1084 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1085 sizeof(struct ip6_hdr), hbhlen); 1086 if (hbh == NULL) { 1087 ip6stat.ip6s_tooshort++; 1088 return; 1089 } 1090 #endif 1091 1092 /* 1093 * XXX: We copy whole the header even if a jumbo 1094 * payload option is included, which option is to 1095 * be removed before returning in the RFC 2292. 1096 * But it's too painful operation... 1097 */ 1098 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1099 IPV6_HOPOPTS, IPPROTO_IPV6); 1100 if (*mp) 1101 mp = &(*mp)->m_next; 1102 } 1103 } 1104 1105 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1106 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 1107 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1108 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 1109 1110 /* 1111 * Search for destination options headers or routing 1112 * header(s) through the header chain, and stores each 1113 * header as ancillary data. 1114 * Note that the order of the headers remains in 1115 * the chain of ancillary data. 1116 */ 1117 while (1) { /* is explicit loop prevention necessary? */ 1118 struct ip6_ext *ip6e; 1119 int elen; 1120 1121 #ifndef PULLDOWN_TEST 1122 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1123 if (nxt == IPPROTO_AH) 1124 elen = (ip6e->ip6e_len + 2) << 2; 1125 else 1126 elen = (ip6e->ip6e_len + 1) << 3; 1127 #else 1128 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, 1129 sizeof(struct ip6_ext)); 1130 if (ip6e == NULL) { 1131 ip6stat.ip6s_tooshort++; 1132 return; 1133 } 1134 if (nxt == IPPROTO_AH) 1135 elen = (ip6e->ip6e_len + 2) << 2; 1136 else 1137 elen = (ip6e->ip6e_len + 1) << 3; 1138 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, elen); 1139 if (ip6e == NULL) { 1140 ip6stat.ip6s_tooshort++; 1141 return; 1142 } 1143 #endif 1144 1145 switch (nxt) { 1146 case IPPROTO_DSTOPTS: 1147 if (!in6p->in6p_flags & IN6P_DSTOPTS) 1148 break; 1149 1150 /* 1151 * We also require super-user privilege for 1152 * the option. 1153 * See the comments on IN6_HOPOPTS. 1154 */ 1155 if (!privileged) 1156 break; 1157 1158 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1159 IPV6_DSTOPTS, 1160 IPPROTO_IPV6); 1161 if (*mp) 1162 mp = &(*mp)->m_next; 1163 break; 1164 1165 case IPPROTO_ROUTING: 1166 if (!in6p->in6p_flags & IN6P_RTHDR) 1167 break; 1168 1169 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1170 IPV6_RTHDR, 1171 IPPROTO_IPV6); 1172 if (*mp) 1173 mp = &(*mp)->m_next; 1174 break; 1175 1176 case IPPROTO_UDP: 1177 case IPPROTO_TCP: 1178 case IPPROTO_ICMPV6: 1179 default: 1180 /* 1181 * stop search if we encounter an upper 1182 * layer protocol headers. 1183 */ 1184 goto loopend; 1185 1186 case IPPROTO_HOPOPTS: 1187 case IPPROTO_AH: /* is it possible? */ 1188 break; 1189 } 1190 1191 /* proceed with the next header. */ 1192 off += elen; 1193 nxt = ip6e->ip6e_nxt; 1194 } 1195 loopend: 1196 ; 1197 } 1198 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1199 /* to be done */ 1200 } 1201 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 1202 /* to be done */ 1203 } 1204 /* IN6P_RTHDR - to be done */ 1205 1206 } 1207 1208 /* 1209 * Get pointer to the previous header followed by the header 1210 * currently processed. 1211 * XXX: This function supposes that 1212 * M includes all headers, 1213 * the next header field and the header length field of each header 1214 * are valid, and 1215 * the sum of each header length equals to OFF. 1216 * Because of these assumptions, this function must be called very 1217 * carefully. Moreover, it will not be used in the near future when 1218 * we develop `neater' mechanism to process extension headers. 1219 */ 1220 char * 1221 ip6_get_prevhdr(m, off) 1222 struct mbuf *m; 1223 int off; 1224 { 1225 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1226 1227 if (off == sizeof(struct ip6_hdr)) 1228 return(&ip6->ip6_nxt); 1229 else { 1230 int len, nxt; 1231 struct ip6_ext *ip6e = NULL; 1232 1233 nxt = ip6->ip6_nxt; 1234 len = sizeof(struct ip6_hdr); 1235 while (len < off) { 1236 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1237 1238 switch (nxt) { 1239 case IPPROTO_FRAGMENT: 1240 len += sizeof(struct ip6_frag); 1241 break; 1242 case IPPROTO_AH: 1243 len += (ip6e->ip6e_len + 2) << 2; 1244 break; 1245 default: 1246 len += (ip6e->ip6e_len + 1) << 3; 1247 break; 1248 } 1249 nxt = ip6e->ip6e_nxt; 1250 } 1251 if (ip6e) 1252 return(&ip6e->ip6e_nxt); 1253 else 1254 return NULL; 1255 } 1256 } 1257 1258 /* 1259 * get next header offset. m will be retained. 1260 */ 1261 int 1262 ip6_nexthdr(m, off, proto, nxtp) 1263 struct mbuf *m; 1264 int off; 1265 int proto; 1266 int *nxtp; 1267 { 1268 struct ip6_hdr ip6; 1269 struct ip6_ext ip6e; 1270 struct ip6_frag fh; 1271 1272 /* just in case */ 1273 if (m == NULL) 1274 panic("ip6_nexthdr: m == NULL"); 1275 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1276 return -1; 1277 1278 switch (proto) { 1279 case IPPROTO_IPV6: 1280 if (m->m_pkthdr.len < off + sizeof(ip6)) 1281 return -1; 1282 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1283 if (nxtp) 1284 *nxtp = ip6.ip6_nxt; 1285 off += sizeof(ip6); 1286 return off; 1287 1288 case IPPROTO_FRAGMENT: 1289 /* 1290 * terminate parsing if it is not the first fragment, 1291 * it does not make sense to parse through it. 1292 */ 1293 if (m->m_pkthdr.len < off + sizeof(fh)) 1294 return -1; 1295 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1296 if ((ntohs(fh.ip6f_offlg) & IP6F_OFF_MASK) != 0) 1297 return -1; 1298 if (nxtp) 1299 *nxtp = fh.ip6f_nxt; 1300 off += sizeof(struct ip6_frag); 1301 return off; 1302 1303 case IPPROTO_AH: 1304 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1305 return -1; 1306 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1307 if (nxtp) 1308 *nxtp = ip6e.ip6e_nxt; 1309 off += (ip6e.ip6e_len + 2) << 2; 1310 return off; 1311 1312 case IPPROTO_HOPOPTS: 1313 case IPPROTO_ROUTING: 1314 case IPPROTO_DSTOPTS: 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 + 1) << 3; 1321 return off; 1322 1323 case IPPROTO_NONE: 1324 case IPPROTO_ESP: 1325 case IPPROTO_IPCOMP: 1326 /* give up */ 1327 return -1; 1328 1329 default: 1330 return -1; 1331 } 1332 1333 return -1; 1334 } 1335 1336 /* 1337 * get offset for the last header in the chain. m will be kept untainted. 1338 */ 1339 int 1340 ip6_lasthdr(m, off, proto, nxtp) 1341 struct mbuf *m; 1342 int off; 1343 int proto; 1344 int *nxtp; 1345 { 1346 int newoff; 1347 int nxt; 1348 1349 if (!nxtp) { 1350 nxt = -1; 1351 nxtp = &nxt; 1352 } 1353 while (1) { 1354 newoff = ip6_nexthdr(m, off, proto, nxtp); 1355 if (newoff < 0) 1356 return off; 1357 else if (newoff < off) 1358 return -1; /* invalid */ 1359 else if (newoff == off) 1360 return newoff; 1361 1362 off = newoff; 1363 proto = *nxtp; 1364 } 1365 } 1366 1367 /* 1368 * System control for IP6 1369 */ 1370 1371 u_char inet6ctlerrmap[PRC_NCMDS] = { 1372 0, 0, 0, 0, 1373 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1374 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1375 EMSGSIZE, EHOSTUNREACH, 0, 0, 1376 0, 0, 0, 0, 1377 ENOPROTOOPT 1378 }; 1379 1380 #include <uvm/uvm_extern.h> 1381 #include <sys/sysctl.h> 1382 1383 int 1384 ip6_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1385 int *name; 1386 u_int namelen; 1387 void *oldp; 1388 size_t *oldlenp; 1389 void *newp; 1390 size_t newlen; 1391 { 1392 int old, error; 1393 1394 /* All sysctl names at this level are terminal. */ 1395 if (namelen != 1) 1396 return ENOTDIR; 1397 1398 switch (name[0]) { 1399 1400 case IPV6CTL_FORWARDING: 1401 return sysctl_int(oldp, oldlenp, newp, newlen, 1402 &ip6_forwarding); 1403 case IPV6CTL_SENDREDIRECTS: 1404 return sysctl_int(oldp, oldlenp, newp, newlen, 1405 &ip6_sendredirects); 1406 case IPV6CTL_DEFHLIM: 1407 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_defhlim); 1408 case IPV6CTL_MAXFRAGPACKETS: 1409 return sysctl_int(oldp, oldlenp, newp, newlen, 1410 &ip6_maxfragpackets); 1411 case IPV6CTL_ACCEPT_RTADV: 1412 return sysctl_int(oldp, oldlenp, newp, newlen, 1413 &ip6_accept_rtadv); 1414 case IPV6CTL_KEEPFAITH: 1415 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_keepfaith); 1416 case IPV6CTL_LOG_INTERVAL: 1417 return sysctl_int(oldp, oldlenp, newp, newlen, 1418 &ip6_log_interval); 1419 case IPV6CTL_HDRNESTLIMIT: 1420 return sysctl_int(oldp, oldlenp, newp, newlen, 1421 &ip6_hdrnestlimit); 1422 case IPV6CTL_DAD_COUNT: 1423 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_dad_count); 1424 case IPV6CTL_AUTO_FLOWLABEL: 1425 return sysctl_int(oldp, oldlenp, newp, newlen, 1426 &ip6_auto_flowlabel); 1427 case IPV6CTL_DEFMCASTHLIM: 1428 return sysctl_int(oldp, oldlenp, newp, newlen, 1429 &ip6_defmcasthlim); 1430 case IPV6CTL_GIF_HLIM: 1431 return sysctl_int(oldp, oldlenp, newp, newlen, 1432 &ip6_gif_hlim); 1433 case IPV6CTL_KAME_VERSION: 1434 return sysctl_rdstring(oldp, oldlenp, newp, __KAME_VERSION); 1435 case IPV6CTL_USE_DEPRECATED: 1436 return sysctl_int(oldp, oldlenp, newp, newlen, 1437 &ip6_use_deprecated); 1438 case IPV6CTL_RR_PRUNE: 1439 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_rr_prune); 1440 #ifndef INET6_BINDV6ONLY 1441 case IPV6CTL_BINDV6ONLY: 1442 return sysctl_int(oldp, oldlenp, newp, newlen, 1443 &ip6_bindv6only); 1444 #endif 1445 case IPV6CTL_ANONPORTMIN: 1446 old = ip6_anonportmin; 1447 error = sysctl_int(oldp, oldlenp, newp, newlen, 1448 &ip6_anonportmin); 1449 if (ip6_anonportmin >= ip6_anonportmax || ip6_anonportmin < 0 || 1450 ip6_anonportmin > 65535 1451 #ifndef IPNOPRIVPORTS 1452 || ip6_anonportmin < IPV6PORT_RESERVED 1453 #endif 1454 ) { 1455 ip6_anonportmin = old; 1456 return (EINVAL); 1457 } 1458 return (error); 1459 case IPV6CTL_ANONPORTMAX: 1460 old = ip6_anonportmax; 1461 error = sysctl_int(oldp, oldlenp, newp, newlen, 1462 &ip6_anonportmax); 1463 if (ip6_anonportmin >= ip6_anonportmax || ip6_anonportmax < 0 || 1464 ip6_anonportmax > 65535 1465 #ifndef IPNOPRIVPORTS 1466 || ip6_anonportmax < IPV6PORT_RESERVED 1467 #endif 1468 ) { 1469 ip6_anonportmax = old; 1470 return (EINVAL); 1471 } 1472 return (error); 1473 #ifndef IPNOPRIVPORTS 1474 case IPV6CTL_LOWPORTMIN: 1475 old = ip6_lowportmin; 1476 error = sysctl_int(oldp, oldlenp, newp, newlen, 1477 &ip6_lowportmin); 1478 if (ip6_lowportmin >= ip6_lowportmax || 1479 ip6_lowportmin > IPV6PORT_RESERVEDMAX || 1480 ip6_lowportmin < IPV6PORT_RESERVEDMIN) { 1481 ip6_lowportmin = old; 1482 return (EINVAL); 1483 } 1484 return (error); 1485 case IPV6CTL_LOWPORTMAX: 1486 old = ip6_lowportmax; 1487 error = sysctl_int(oldp, oldlenp, newp, newlen, 1488 &ip6_lowportmax); 1489 if (ip6_lowportmin >= ip6_lowportmax || 1490 ip6_lowportmax > IPV6PORT_RESERVEDMAX || 1491 ip6_lowportmax < IPV6PORT_RESERVEDMIN) { 1492 ip6_lowportmax = old; 1493 return (EINVAL); 1494 } 1495 return (error); 1496 #endif 1497 default: 1498 return EOPNOTSUPP; 1499 } 1500 /* NOTREACHED */ 1501 } 1502
Indexes created Wed Sep 24 05:09:52 GMT 2025