1 /* $NetBSD: ip6_input.c,v 1.33 2000/12/28 21:41:00 thorpej Exp $ */ 2 /* $KAME: ip6_input.c,v 1.121 2000/08/31 06:07:29 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 IPV6FIREWALL 111 #include <netinet6/ip6_fw.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 IPV6FIREWALL 138 /* firewall hooks */ 139 ip6_fw_chk_t *ip6_fw_chk_ptr; 140 ip6_fw_ctl_t *ip6_fw_ctl_ptr; 141 #endif 142 143 #ifdef PFIL_HOOKS 144 struct pfil_head inet6_pfil_hook; 145 #endif 146 147 struct ip6stat ip6stat; 148 149 static void ip6_init2 __P((void *)); 150 151 static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *)); 152 153 /* 154 * IP6 initialization: fill in IP6 protocol switch table. 155 * All protocols not implemented in kernel go to raw IP6 protocol handler. 156 */ 157 void 158 ip6_init() 159 { 160 register struct ip6protosw *pr; 161 register int i; 162 struct timeval tv; 163 164 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 165 if (pr == 0) 166 panic("ip6_init"); 167 for (i = 0; i < IPPROTO_MAX; i++) 168 ip6_protox[i] = pr - inet6sw; 169 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 170 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 171 if (pr->pr_domain->dom_family == PF_INET6 && 172 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 173 ip6_protox[pr->pr_protocol] = pr - inet6sw; 174 ip6intrq.ifq_maxlen = ip6qmaxlen; 175 nd6_init(); 176 frag6_init(); 177 #ifdef IPV6FIREWALL 178 ip6_fw_init(); 179 #endif 180 /* 181 * in many cases, random() here does NOT return random number 182 * as initialization during bootstrap time occur in fixed order. 183 */ 184 microtime(&tv); 185 ip6_flow_seq = random() ^ tv.tv_usec; 186 187 ip6_init2((void *)0); 188 189 #ifdef PFIL_HOOKS 190 /* Register our Packet Filter hook. */ 191 inet6_pfil_hook.ph_type = PFIL_TYPE_AF; 192 inet6_pfil_hook.ph_af = AF_INET6; 193 i = pfil_head_register(&inet6_pfil_hook); 194 if (i != 0) 195 printf("ip6_init: WARNING: unable to register pfil hook, " 196 "error %d\n", i); 197 #endif /* PFIL_HOOKS */ 198 } 199 200 static void 201 ip6_init2(dummy) 202 void *dummy; 203 { 204 /* 205 * to route local address of p2p link to loopback, 206 * assign loopback address first. 207 */ 208 in6_ifattach(&loif[0], NULL); 209 210 /* nd6_timer_init */ 211 callout_init(&nd6_timer_ch); 212 callout_reset(&nd6_timer_ch, hz, nd6_timer, NULL); 213 /* router renumbering prefix list maintenance */ 214 callout_init(&in6_rr_timer_ch); 215 callout_reset(&in6_rr_timer_ch, hz, in6_rr_timer, NULL); 216 } 217 218 /* 219 * IP6 input interrupt handling. Just pass the packet to ip6_input. 220 */ 221 void 222 ip6intr() 223 { 224 int s; 225 struct mbuf *m; 226 227 for (;;) { 228 s = splimp(); 229 IF_DEQUEUE(&ip6intrq, m); 230 splx(s); 231 if (m == 0) 232 return; 233 ip6_input(m); 234 } 235 } 236 237 extern struct route_in6 ip6_forward_rt; 238 239 void 240 ip6_input(m) 241 struct mbuf *m; 242 { 243 struct ip6_hdr *ip6; 244 int off = sizeof(struct ip6_hdr), nest; 245 u_int32_t plen; 246 u_int32_t rtalert = ~0; 247 int nxt, ours = 0; 248 struct ifnet *deliverifp = NULL; 249 250 #ifdef IPSEC 251 /* 252 * should the inner packet be considered authentic? 253 * see comment in ah4_input(). 254 */ 255 if (m) { 256 m->m_flags &= ~M_AUTHIPHDR; 257 m->m_flags &= ~M_AUTHIPDGM; 258 } 259 #endif 260 261 /* 262 * mbuf statistics by kazu 263 */ 264 if (m->m_flags & M_EXT) { 265 if (m->m_next) 266 ip6stat.ip6s_mext2m++; 267 else 268 ip6stat.ip6s_mext1++; 269 } else { 270 if (m->m_next) { 271 if (m->m_flags & M_LOOP) { 272 ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/ 273 } else if (m->m_pkthdr.rcvif->if_index <= 31) 274 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 275 else 276 ip6stat.ip6s_m2m[0]++; 277 } else 278 ip6stat.ip6s_m1++; 279 } 280 281 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 282 ip6stat.ip6s_total++; 283 284 #ifndef PULLDOWN_TEST 285 /* XXX is the line really necessary? */ 286 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/); 287 #endif 288 289 if (m->m_len < sizeof(struct ip6_hdr)) { 290 struct ifnet *inifp; 291 inifp = m->m_pkthdr.rcvif; 292 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 293 ip6stat.ip6s_toosmall++; 294 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 295 return; 296 } 297 } 298 299 ip6 = mtod(m, struct ip6_hdr *); 300 301 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 302 ip6stat.ip6s_badvers++; 303 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 304 goto bad; 305 } 306 307 #ifdef PFIL_HOOKS 308 /* 309 * Run through list of hooks for input packets. If there are any 310 * filters which require that additional packets in the flow are 311 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 312 * Note that filters must _never_ set this flag, as another filter 313 * in the list may have previously cleared it. 314 */ 315 if (pfil_run_hooks(&inet6_pfil_hook, &m, m->m_pkthdr.rcvif, 316 PFIL_IN) != 0) 317 return; 318 if (m == NULL) 319 return; 320 ip6 = mtod(m, struct ip6_hdr *); 321 #endif /* PFIL_HOOKS */ 322 323 324 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 325 326 #ifdef IPV6FIREWALL 327 /* 328 * Check with the firewall... 329 */ 330 if (ip6_fw_chk_ptr) { 331 u_short port = 0; 332 /* If ipfw says divert, we have to just drop packet */ 333 /* use port as a dummy argument */ 334 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) { 335 m_freem(m); 336 m = NULL; 337 } 338 if (!m) 339 return; 340 } 341 #endif 342 343 #ifdef ALTQ 344 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 345 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 346 /* packet is dropped by traffic conditioner */ 347 return; 348 } 349 #endif 350 351 /* 352 * Scope check 353 */ 354 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 355 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 356 ip6stat.ip6s_badscope++; 357 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 358 goto bad; 359 } 360 /* 361 * The following check is not documented in the spec. Malicious party 362 * may be able to use IPv4 mapped addr to confuse tcp/udp stack and 363 * bypass security checks (act as if it was from 127.0.0.1 by using 364 * IPv6 src ::ffff:127.0.0.1). Be cautious. 365 */ 366 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 367 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 368 ip6stat.ip6s_badscope++; 369 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 370 goto bad; 371 } 372 #if 0 373 /* 374 * Reject packets with IPv4 compatible addresses (auto tunnel). 375 * 376 * The code forbids auto tunnel relay case in RFC1933 (the check is 377 * stronger than RFC1933). We may want to re-enable it if mech-xx 378 * is revised to forbid relaying case. 379 */ 380 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 381 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 382 ip6stat.ip6s_badscope++; 383 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 384 goto bad; 385 } 386 #endif 387 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 388 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 389 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 390 ours = 1; 391 deliverifp = m->m_pkthdr.rcvif; 392 goto hbhcheck; 393 } else { 394 ip6stat.ip6s_badscope++; 395 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 396 goto bad; 397 } 398 } 399 400 #ifndef FAKE_LOOPBACK_IF 401 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) 402 #else 403 if (1) 404 #endif 405 { 406 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 407 ip6->ip6_src.s6_addr16[1] 408 = htons(m->m_pkthdr.rcvif->if_index); 409 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 410 ip6->ip6_dst.s6_addr16[1] 411 = htons(m->m_pkthdr.rcvif->if_index); 412 } 413 414 /* 415 * XXX we need this since we do not have "goto ours" hack route 416 * for some of our ifaddrs on loopback interface. 417 * we should correct it by changing in6_ifattach to install 418 * "goto ours" hack route. 419 */ 420 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) != 0) { 421 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 422 ours = 1; 423 deliverifp = m->m_pkthdr.rcvif; 424 goto hbhcheck; 425 } 426 } 427 428 /* 429 * Multicast check 430 */ 431 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 432 struct in6_multi *in6m = 0; 433 434 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 435 /* 436 * See if we belong to the destination multicast group on the 437 * arrival interface. 438 */ 439 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 440 if (in6m) 441 ours = 1; 442 else if (!ip6_mrouter) { 443 ip6stat.ip6s_notmember++; 444 ip6stat.ip6s_cantforward++; 445 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 446 goto bad; 447 } 448 deliverifp = m->m_pkthdr.rcvif; 449 goto hbhcheck; 450 } 451 452 /* 453 * Unicast check 454 */ 455 if (ip6_forward_rt.ro_rt != NULL && 456 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) != 0 && 457 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 458 &ip6_forward_rt.ro_dst.sin6_addr)) 459 ip6stat.ip6s_forward_cachehit++; 460 else { 461 if (ip6_forward_rt.ro_rt) { 462 /* route is down or destination is different */ 463 ip6stat.ip6s_forward_cachemiss++; 464 RTFREE(ip6_forward_rt.ro_rt); 465 ip6_forward_rt.ro_rt = 0; 466 } 467 468 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 469 ip6_forward_rt.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 470 ip6_forward_rt.ro_dst.sin6_family = AF_INET6; 471 ip6_forward_rt.ro_dst.sin6_addr = ip6->ip6_dst; 472 473 rtalloc((struct route *)&ip6_forward_rt); 474 } 475 476 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 477 478 /* 479 * Accept the packet if the forwarding interface to the destination 480 * according to the routing table is the loopback interface, 481 * unless the associated route has a gateway. 482 * Note that this approach causes to accept a packet if there is a 483 * route to the loopback interface for the destination of the packet. 484 * But we think it's even useful in some situations, e.g. when using 485 * a special daemon which wants to intercept the packet. 486 */ 487 if (ip6_forward_rt.ro_rt && 488 (ip6_forward_rt.ro_rt->rt_flags & 489 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 490 #if 0 491 /* 492 * The check below is redundant since the comparison of 493 * the destination and the key of the rtentry has 494 * already done through looking up the routing table. 495 */ 496 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 497 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) && 498 #endif 499 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 500 struct in6_ifaddr *ia6 = 501 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 502 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 503 m->m_flags |= M_ANYCAST6; 504 /* 505 * packets to a tentative, duplicated, or somehow invalid 506 * address must not be accepted. 507 */ 508 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 509 /* this address is ready */ 510 ours = 1; 511 deliverifp = ia6->ia_ifp; /* correct? */ 512 goto hbhcheck; 513 } else { 514 /* address is not ready, so discard the packet. */ 515 log(LOG_INFO, 516 "ip6_input: packet to an unready address %s->%s\n", 517 ip6_sprintf(&ip6->ip6_src), 518 ip6_sprintf(&ip6->ip6_dst)); 519 520 goto bad; 521 } 522 } 523 524 /* 525 * FAITH(Firewall Aided Internet Translator) 526 */ 527 #if defined(NFAITH) && 0 < NFAITH 528 if (ip6_keepfaith) { 529 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 530 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 531 /* XXX do we need more sanity checks? */ 532 ours = 1; 533 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 534 goto hbhcheck; 535 } 536 } 537 #endif 538 539 #if 0 540 { 541 /* 542 * Last resort: check in6_ifaddr for incoming interface. 543 * The code is here until I update the "goto ours hack" code above 544 * working right. 545 */ 546 struct ifaddr *ifa; 547 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 548 ifa; 549 ifa = ifa->ifa_list.tqe_next) { 550 if (ifa->ifa_addr == NULL) 551 continue; /* just for safety */ 552 if (ifa->ifa_addr->sa_family != AF_INET6) 553 continue; 554 if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ip6->ip6_dst)) { 555 ours = 1; 556 deliverifp = ifa->ifa_ifp; 557 goto hbhcheck; 558 } 559 } 560 } 561 #endif 562 563 /* 564 * Now there is no reason to process the packet if it's not our own 565 * and we're not a router. 566 */ 567 if (!ip6_forwarding) { 568 ip6stat.ip6s_cantforward++; 569 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 570 goto bad; 571 } 572 573 hbhcheck: 574 /* 575 * Process Hop-by-Hop options header if it's contained. 576 * m may be modified in ip6_hopopts_input(). 577 * If a JumboPayload option is included, plen will also be modified. 578 */ 579 plen = (u_int32_t)ntohs(ip6->ip6_plen); 580 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 581 struct ip6_hbh *hbh; 582 583 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 584 #if 0 /*touches NULL pointer*/ 585 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 586 #endif 587 return; /* m have already been freed */ 588 } 589 590 /* adjust pointer */ 591 ip6 = mtod(m, struct ip6_hdr *); 592 593 /* 594 * if the payload length field is 0 and the next header field 595 * indicates Hop-by-Hop Options header, then a Jumbo Payload 596 * option MUST be included. 597 */ 598 if (ip6->ip6_plen == 0 && plen == 0) { 599 /* 600 * Note that if a valid jumbo payload option is 601 * contained, ip6_hoptops_input() must set a valid 602 * (non-zero) payload length to the variable plen. 603 */ 604 ip6stat.ip6s_badoptions++; 605 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 606 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 607 icmp6_error(m, ICMP6_PARAM_PROB, 608 ICMP6_PARAMPROB_HEADER, 609 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 610 return; 611 } 612 #ifndef PULLDOWN_TEST 613 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 614 hbh = (struct ip6_hbh *)(ip6 + 1); 615 #else 616 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 617 sizeof(struct ip6_hbh)); 618 if (hbh == NULL) { 619 ip6stat.ip6s_tooshort++; 620 return; 621 } 622 #endif 623 nxt = hbh->ip6h_nxt; 624 625 /* 626 * accept the packet if a router alert option is included 627 * and we act as an IPv6 router. 628 */ 629 if (rtalert != ~0 && ip6_forwarding) 630 ours = 1; 631 } else 632 nxt = ip6->ip6_nxt; 633 634 /* 635 * Check that the amount of data in the buffers 636 * is as at least much as the IPv6 header would have us expect. 637 * Trim mbufs if longer than we expect. 638 * Drop packet if shorter than we expect. 639 */ 640 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 641 ip6stat.ip6s_tooshort++; 642 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 643 goto bad; 644 } 645 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 646 if (m->m_len == m->m_pkthdr.len) { 647 m->m_len = sizeof(struct ip6_hdr) + plen; 648 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 649 } else 650 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 651 } 652 653 /* 654 * Forward if desirable. 655 */ 656 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 657 /* 658 * If we are acting as a multicast router, all 659 * incoming multicast packets are passed to the 660 * kernel-level multicast forwarding function. 661 * The packet is returned (relatively) intact; if 662 * ip6_mforward() returns a non-zero value, the packet 663 * must be discarded, else it may be accepted below. 664 */ 665 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 666 ip6stat.ip6s_cantforward++; 667 m_freem(m); 668 return; 669 } 670 if (!ours) { 671 m_freem(m); 672 return; 673 } 674 } else if (!ours) { 675 ip6_forward(m, 0); 676 return; 677 } 678 679 ip6 = mtod(m, struct ip6_hdr *); 680 681 /* 682 * Malicious party may be able to use IPv4 mapped addr to confuse 683 * tcp/udp stack and bypass security checks (act as if it was from 684 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 685 * 686 * For SIIT end node behavior, you may want to disable the check. 687 * However, you will become vulnerable to attacks using IPv4 mapped 688 * source. 689 */ 690 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 691 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 692 ip6stat.ip6s_badscope++; 693 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 694 goto bad; 695 } 696 697 /* 698 * Tell launch routine the next header 699 */ 700 #ifdef IFA_STATS 701 if (deliverifp != NULL) { 702 struct in6_ifaddr *ia6; 703 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 704 if (ia6) 705 ia6->ia_ifa.ifa_data.ifad_inbytes += m->m_pkthdr.len; 706 } 707 #endif 708 ip6stat.ip6s_delivered++; 709 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 710 nest = 0; 711 while (nxt != IPPROTO_DONE) { 712 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 713 ip6stat.ip6s_toomanyhdr++; 714 goto bad; 715 } 716 717 /* 718 * protection against faulty packet - there should be 719 * more sanity checks in header chain processing. 720 */ 721 if (m->m_pkthdr.len < off) { 722 ip6stat.ip6s_tooshort++; 723 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 724 goto bad; 725 } 726 727 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 728 } 729 return; 730 bad: 731 m_freem(m); 732 } 733 734 /* 735 * Hop-by-Hop options header processing. If a valid jumbo payload option is 736 * included, the real payload length will be stored in plenp. 737 */ 738 static int 739 ip6_hopopts_input(plenp, rtalertp, mp, offp) 740 u_int32_t *plenp; 741 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 742 struct mbuf **mp; 743 int *offp; 744 { 745 register struct mbuf *m = *mp; 746 int off = *offp, hbhlen; 747 struct ip6_hbh *hbh; 748 u_int8_t *opt; 749 750 /* validation of the length of the header */ 751 #ifndef PULLDOWN_TEST 752 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 753 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 754 hbhlen = (hbh->ip6h_len + 1) << 3; 755 756 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 757 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 758 #else 759 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 760 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 761 if (hbh == NULL) { 762 ip6stat.ip6s_tooshort++; 763 return -1; 764 } 765 hbhlen = (hbh->ip6h_len + 1) << 3; 766 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 767 hbhlen); 768 if (hbh == NULL) { 769 ip6stat.ip6s_tooshort++; 770 return -1; 771 } 772 #endif 773 off += hbhlen; 774 hbhlen -= sizeof(struct ip6_hbh); 775 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 776 777 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 778 hbhlen, rtalertp, plenp) < 0) 779 return(-1); 780 781 *offp = off; 782 *mp = m; 783 return(0); 784 } 785 786 /* 787 * Search header for all Hop-by-hop options and process each option. 788 * This function is separate from ip6_hopopts_input() in order to 789 * handle a case where the sending node itself process its hop-by-hop 790 * options header. In such a case, the function is called from ip6_output(). 791 */ 792 int 793 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 794 struct mbuf *m; 795 u_int8_t *opthead; 796 int hbhlen; 797 u_int32_t *rtalertp; 798 u_int32_t *plenp; 799 { 800 struct ip6_hdr *ip6; 801 int optlen = 0; 802 u_int8_t *opt = opthead; 803 u_int16_t rtalert_val; 804 u_int32_t jumboplen; 805 806 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 807 switch(*opt) { 808 case IP6OPT_PAD1: 809 optlen = 1; 810 break; 811 case IP6OPT_PADN: 812 if (hbhlen < IP6OPT_MINLEN) { 813 ip6stat.ip6s_toosmall++; 814 goto bad; 815 } 816 optlen = *(opt + 1) + 2; 817 break; 818 case IP6OPT_RTALERT: 819 /* XXX may need check for alignment */ 820 if (hbhlen < IP6OPT_RTALERT_LEN) { 821 ip6stat.ip6s_toosmall++; 822 goto bad; 823 } 824 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) 825 /* XXX: should we discard the packet? */ 826 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 827 *(opt + 1)); 828 optlen = IP6OPT_RTALERT_LEN; 829 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 830 *rtalertp = ntohs(rtalert_val); 831 break; 832 case IP6OPT_JUMBO: 833 /* XXX may need check for alignment */ 834 if (hbhlen < IP6OPT_JUMBO_LEN) { 835 ip6stat.ip6s_toosmall++; 836 goto bad; 837 } 838 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) 839 /* XXX: should we discard the packet? */ 840 log(LOG_ERR, "length of jumbopayload opt " 841 "is inconsistent(%d)\n", 842 *(opt + 1)); 843 optlen = IP6OPT_JUMBO_LEN; 844 845 /* 846 * IPv6 packets that have non 0 payload length 847 * must not contain a jumbo paylod option. 848 */ 849 ip6 = mtod(m, struct ip6_hdr *); 850 if (ip6->ip6_plen) { 851 ip6stat.ip6s_badoptions++; 852 icmp6_error(m, ICMP6_PARAM_PROB, 853 ICMP6_PARAMPROB_HEADER, 854 sizeof(struct ip6_hdr) + 855 sizeof(struct ip6_hbh) + 856 opt - opthead); 857 return(-1); 858 } 859 860 /* 861 * We may see jumbolen in unaligned location, so 862 * we'd need to perform bcopy(). 863 */ 864 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 865 jumboplen = (u_int32_t)htonl(jumboplen); 866 867 #if 1 868 /* 869 * if there are multiple jumbo payload options, 870 * *plenp will be non-zero and the packet will be 871 * rejected. 872 * the behavior may need some debate in ipngwg - 873 * multiple options does not make sense, however, 874 * there's no explicit mention in specification. 875 */ 876 if (*plenp != 0) { 877 ip6stat.ip6s_badoptions++; 878 icmp6_error(m, ICMP6_PARAM_PROB, 879 ICMP6_PARAMPROB_HEADER, 880 sizeof(struct ip6_hdr) + 881 sizeof(struct ip6_hbh) + 882 opt + 2 - opthead); 883 return(-1); 884 } 885 #endif 886 887 /* 888 * jumbo payload length must be larger than 65535. 889 */ 890 if (jumboplen <= IPV6_MAXPACKET) { 891 ip6stat.ip6s_badoptions++; 892 icmp6_error(m, ICMP6_PARAM_PROB, 893 ICMP6_PARAMPROB_HEADER, 894 sizeof(struct ip6_hdr) + 895 sizeof(struct ip6_hbh) + 896 opt + 2 - opthead); 897 return(-1); 898 } 899 *plenp = jumboplen; 900 901 break; 902 default: /* unknown option */ 903 if (hbhlen < IP6OPT_MINLEN) { 904 ip6stat.ip6s_toosmall++; 905 goto bad; 906 } 907 if ((optlen = ip6_unknown_opt(opt, m, 908 sizeof(struct ip6_hdr) + 909 sizeof(struct ip6_hbh) + 910 opt - opthead)) == -1) 911 return(-1); 912 optlen += 2; 913 break; 914 } 915 } 916 917 return(0); 918 919 bad: 920 m_freem(m); 921 return(-1); 922 } 923 924 /* 925 * Unknown option processing. 926 * The third argument `off' is the offset from the IPv6 header to the option, 927 * which is necessary if the IPv6 header the and option header and IPv6 header 928 * is not continuous in order to return an ICMPv6 error. 929 */ 930 int 931 ip6_unknown_opt(optp, m, off) 932 u_int8_t *optp; 933 struct mbuf *m; 934 int off; 935 { 936 struct ip6_hdr *ip6; 937 938 switch(IP6OPT_TYPE(*optp)) { 939 case IP6OPT_TYPE_SKIP: /* ignore the option */ 940 return((int)*(optp + 1)); 941 case IP6OPT_TYPE_DISCARD: /* silently discard */ 942 m_freem(m); 943 return(-1); 944 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 945 ip6stat.ip6s_badoptions++; 946 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 947 return(-1); 948 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 949 ip6stat.ip6s_badoptions++; 950 ip6 = mtod(m, struct ip6_hdr *); 951 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 952 (m->m_flags & (M_BCAST|M_MCAST))) 953 m_freem(m); 954 else 955 icmp6_error(m, ICMP6_PARAM_PROB, 956 ICMP6_PARAMPROB_OPTION, off); 957 return(-1); 958 } 959 960 m_freem(m); /* XXX: NOTREACHED */ 961 return(-1); 962 } 963 964 /* 965 * Create the "control" list for this pcb. 966 * 967 * The routine will be called from upper layer handlers like tcp6_input(). 968 * Thus the routine assumes that the caller (tcp6_input) have already 969 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 970 * very first mbuf on the mbuf chain. 971 * We may want to add some infinite loop prevention or sanity checks for safety. 972 * (This applies only when you are using KAME mbuf chain restriction, i.e. 973 * you are using IP6_EXTHDR_CHECK() not m_pulldown()) 974 */ 975 void 976 ip6_savecontrol(in6p, mp, ip6, m) 977 register struct in6pcb *in6p; 978 register struct mbuf **mp; 979 register struct ip6_hdr *ip6; 980 register struct mbuf *m; 981 { 982 struct proc *p = curproc; /* XXX */ 983 int privileged; 984 985 privileged = 0; 986 if (p && !suser(p->p_ucred, &p->p_acflag)) 987 privileged++; 988 989 #ifdef SO_TIMESTAMP 990 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 991 struct timeval tv; 992 993 microtime(&tv); 994 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 995 SCM_TIMESTAMP, SOL_SOCKET); 996 if (*mp) 997 mp = &(*mp)->m_next; 998 } 999 #endif 1000 if (in6p->in6p_flags & IN6P_RECVDSTADDR) { 1001 *mp = sbcreatecontrol((caddr_t) &ip6->ip6_dst, 1002 sizeof(struct in6_addr), IPV6_RECVDSTADDR, 1003 IPPROTO_IPV6); 1004 if (*mp) 1005 mp = &(*mp)->m_next; 1006 } 1007 1008 #ifdef noyet 1009 /* options were tossed above */ 1010 if (in6p->in6p_flags & IN6P_RECVOPTS) 1011 /* broken */ 1012 /* ip6_srcroute doesn't do what we want here, need to fix */ 1013 if (in6p->in6p_flags & IPV6P_RECVRETOPTS) 1014 /* broken */ 1015 #endif 1016 1017 /* RFC 2292 sec. 5 */ 1018 if (in6p->in6p_flags & IN6P_PKTINFO) { 1019 struct in6_pktinfo pi6; 1020 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1021 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 1022 pi6.ipi6_addr.s6_addr16[1] = 0; 1023 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 1024 ? m->m_pkthdr.rcvif->if_index 1025 : 0; 1026 *mp = sbcreatecontrol((caddr_t) &pi6, 1027 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 1028 IPPROTO_IPV6); 1029 if (*mp) 1030 mp = &(*mp)->m_next; 1031 } 1032 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 1033 int hlim = ip6->ip6_hlim & 0xff; 1034 *mp = sbcreatecontrol((caddr_t) &hlim, 1035 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 1036 if (*mp) 1037 mp = &(*mp)->m_next; 1038 } 1039 /* IN6P_NEXTHOP - for outgoing packet only */ 1040 1041 /* 1042 * IPV6_HOPOPTS socket option. We require super-user privilege 1043 * for the option, but it might be too strict, since there might 1044 * be some hop-by-hop options which can be returned to normal user. 1045 * See RFC 2292 section 6. 1046 */ 1047 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1048 /* 1049 * Check if a hop-by-hop options header is contatined in the 1050 * received packet, and if so, store the options as ancillary 1051 * data. Note that a hop-by-hop options header must be 1052 * just after the IPv6 header, which fact is assured through 1053 * the IPv6 input processing. 1054 */ 1055 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1056 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1057 struct ip6_hbh *hbh; 1058 int hbhlen; 1059 1060 #ifndef PULLDOWN_TEST 1061 hbh = (struct ip6_hbh *)(ip6 + 1); 1062 hbhlen = (hbh->ip6h_len + 1) << 3; 1063 #else 1064 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1065 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 1066 if (hbh == NULL) { 1067 ip6stat.ip6s_tooshort++; 1068 return; 1069 } 1070 hbhlen = (hbh->ip6h_len + 1) << 3; 1071 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 1072 sizeof(struct ip6_hdr), hbhlen); 1073 if (hbh == NULL) { 1074 ip6stat.ip6s_tooshort++; 1075 return; 1076 } 1077 #endif 1078 1079 /* 1080 * XXX: We copy whole the header even if a jumbo 1081 * payload option is included, which option is to 1082 * be removed before returning in the RFC 2292. 1083 * But it's too painful operation... 1084 */ 1085 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1086 IPV6_HOPOPTS, IPPROTO_IPV6); 1087 if (*mp) 1088 mp = &(*mp)->m_next; 1089 } 1090 } 1091 1092 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1093 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 1094 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1095 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 1096 1097 /* 1098 * Search for destination options headers or routing 1099 * header(s) through the header chain, and stores each 1100 * header as ancillary data. 1101 * Note that the order of the headers remains in 1102 * the chain of ancillary data. 1103 */ 1104 while(1) { /* is explicit loop prevention necessary? */ 1105 struct ip6_ext *ip6e; 1106 int elen; 1107 1108 #ifndef PULLDOWN_TEST 1109 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1110 if (nxt == IPPROTO_AH) 1111 elen = (ip6e->ip6e_len + 2) << 2; 1112 else 1113 elen = (ip6e->ip6e_len + 1) << 3; 1114 #else 1115 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, 1116 sizeof(struct ip6_ext)); 1117 if (ip6e == NULL) { 1118 ip6stat.ip6s_tooshort++; 1119 return; 1120 } 1121 if (nxt == IPPROTO_AH) 1122 elen = (ip6e->ip6e_len + 2) << 2; 1123 else 1124 elen = (ip6e->ip6e_len + 1) << 3; 1125 IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off, elen); 1126 if (ip6e == NULL) { 1127 ip6stat.ip6s_tooshort++; 1128 return; 1129 } 1130 #endif 1131 1132 switch(nxt) { 1133 case IPPROTO_DSTOPTS: 1134 if (!in6p->in6p_flags & IN6P_DSTOPTS) 1135 break; 1136 1137 /* 1138 * We also require super-user privilege for 1139 * the option. 1140 * See the comments on IN6_HOPOPTS. 1141 */ 1142 if (!privileged) 1143 break; 1144 1145 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1146 IPV6_DSTOPTS, 1147 IPPROTO_IPV6); 1148 if (*mp) 1149 mp = &(*mp)->m_next; 1150 break; 1151 1152 case IPPROTO_ROUTING: 1153 if (!in6p->in6p_flags & IN6P_RTHDR) 1154 break; 1155 1156 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1157 IPV6_RTHDR, 1158 IPPROTO_IPV6); 1159 if (*mp) 1160 mp = &(*mp)->m_next; 1161 break; 1162 1163 case IPPROTO_UDP: 1164 case IPPROTO_TCP: 1165 case IPPROTO_ICMPV6: 1166 default: 1167 /* 1168 * stop search if we encounter an upper 1169 * layer protocol headers. 1170 */ 1171 goto loopend; 1172 1173 case IPPROTO_HOPOPTS: 1174 case IPPROTO_AH: /* is it possible? */ 1175 break; 1176 } 1177 1178 /* proceed with the next header. */ 1179 off += elen; 1180 nxt = ip6e->ip6e_nxt; 1181 } 1182 loopend: 1183 } 1184 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1185 /* to be done */ 1186 } 1187 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 1188 /* to be done */ 1189 } 1190 /* IN6P_RTHDR - to be done */ 1191 1192 } 1193 1194 /* 1195 * Get pointer to the previous header followed by the header 1196 * currently processed. 1197 * XXX: This function supposes that 1198 * M includes all headers, 1199 * the next header field and the header length field of each header 1200 * are valid, and 1201 * the sum of each header length equals to OFF. 1202 * Because of these assumptions, this function must be called very 1203 * carefully. Moreover, it will not be used in the near future when 1204 * we develop `neater' mechanism to process extension headers. 1205 */ 1206 char * 1207 ip6_get_prevhdr(m, off) 1208 struct mbuf *m; 1209 int off; 1210 { 1211 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1212 1213 if (off == sizeof(struct ip6_hdr)) 1214 return(&ip6->ip6_nxt); 1215 else { 1216 int len, nxt; 1217 struct ip6_ext *ip6e = NULL; 1218 1219 nxt = ip6->ip6_nxt; 1220 len = sizeof(struct ip6_hdr); 1221 while (len < off) { 1222 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1223 1224 switch(nxt) { 1225 case IPPROTO_FRAGMENT: 1226 len += sizeof(struct ip6_frag); 1227 break; 1228 case IPPROTO_AH: 1229 len += (ip6e->ip6e_len + 2) << 2; 1230 break; 1231 default: 1232 len += (ip6e->ip6e_len + 1) << 3; 1233 break; 1234 } 1235 nxt = ip6e->ip6e_nxt; 1236 } 1237 if (ip6e) 1238 return(&ip6e->ip6e_nxt); 1239 else 1240 return NULL; 1241 } 1242 } 1243 1244 /* 1245 * get next header offset. m will be retained. 1246 */ 1247 int 1248 ip6_nexthdr(m, off, proto, nxtp) 1249 struct mbuf *m; 1250 int off; 1251 int proto; 1252 int *nxtp; 1253 { 1254 struct ip6_hdr ip6; 1255 struct ip6_ext ip6e; 1256 struct ip6_frag fh; 1257 1258 /* just in case */ 1259 if (m == NULL) 1260 panic("ip6_nexthdr: m == NULL"); 1261 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1262 return -1; 1263 1264 switch (proto) { 1265 case IPPROTO_IPV6: 1266 if (m->m_pkthdr.len < off + sizeof(ip6)) 1267 return -1; 1268 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1269 if (nxtp) 1270 *nxtp = ip6.ip6_nxt; 1271 off += sizeof(ip6); 1272 return off; 1273 1274 case IPPROTO_FRAGMENT: 1275 /* 1276 * terminate parsing if it is not the first fragment, 1277 * it does not make sense to parse through it. 1278 */ 1279 if (m->m_pkthdr.len < off + sizeof(fh)) 1280 return -1; 1281 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1282 if ((ntohs(fh.ip6f_offlg) & IP6F_OFF_MASK) != 0) 1283 return -1; 1284 if (nxtp) 1285 *nxtp = fh.ip6f_nxt; 1286 off += sizeof(struct ip6_frag); 1287 return off; 1288 1289 case IPPROTO_AH: 1290 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1291 return -1; 1292 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1293 if (nxtp) 1294 *nxtp = ip6e.ip6e_nxt; 1295 off += (ip6e.ip6e_len + 2) << 2; 1296 return off; 1297 1298 case IPPROTO_HOPOPTS: 1299 case IPPROTO_ROUTING: 1300 case IPPROTO_DSTOPTS: 1301 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1302 return -1; 1303 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1304 if (nxtp) 1305 *nxtp = ip6e.ip6e_nxt; 1306 off += (ip6e.ip6e_len + 1) << 3; 1307 return off; 1308 1309 case IPPROTO_NONE: 1310 case IPPROTO_ESP: 1311 case IPPROTO_IPCOMP: 1312 /* give up */ 1313 return -1; 1314 1315 default: 1316 return -1; 1317 } 1318 1319 return -1; 1320 } 1321 1322 /* 1323 * get offset for the last header in the chain. m will be kept untainted. 1324 */ 1325 int 1326 ip6_lasthdr(m, off, proto, nxtp) 1327 struct mbuf *m; 1328 int off; 1329 int proto; 1330 int *nxtp; 1331 { 1332 int newoff; 1333 int nxt; 1334 1335 if (!nxtp) { 1336 nxt = -1; 1337 nxtp = &nxt; 1338 } 1339 while (1) { 1340 newoff = ip6_nexthdr(m, off, proto, nxtp); 1341 if (newoff < 0) 1342 return off; 1343 else if (newoff < off) 1344 return -1; /* invalid */ 1345 else if (newoff == off) 1346 return newoff; 1347 1348 off = newoff; 1349 proto = *nxtp; 1350 } 1351 } 1352 1353 /* 1354 * System control for IP6 1355 */ 1356 1357 u_char inet6ctlerrmap[PRC_NCMDS] = { 1358 0, 0, 0, 0, 1359 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1360 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1361 EMSGSIZE, EHOSTUNREACH, 0, 0, 1362 0, 0, 0, 0, 1363 ENOPROTOOPT 1364 }; 1365 1366 #include <uvm/uvm_extern.h> 1367 #include <sys/sysctl.h> 1368 1369 int 1370 ip6_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1371 int *name; 1372 u_int namelen; 1373 void *oldp; 1374 size_t *oldlenp; 1375 void *newp; 1376 size_t newlen; 1377 { 1378 int old, error; 1379 1380 /* All sysctl names at this level are terminal. */ 1381 if (namelen != 1) 1382 return ENOTDIR; 1383 1384 switch (name[0]) { 1385 1386 case IPV6CTL_FORWARDING: 1387 return sysctl_int(oldp, oldlenp, newp, newlen, 1388 &ip6_forwarding); 1389 case IPV6CTL_SENDREDIRECTS: 1390 return sysctl_int(oldp, oldlenp, newp, newlen, 1391 &ip6_sendredirects); 1392 case IPV6CTL_DEFHLIM: 1393 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_defhlim); 1394 case IPV6CTL_MAXFRAGPACKETS: 1395 return sysctl_int(oldp, oldlenp, newp, newlen, 1396 &ip6_maxfragpackets); 1397 case IPV6CTL_ACCEPT_RTADV: 1398 return sysctl_int(oldp, oldlenp, newp, newlen, 1399 &ip6_accept_rtadv); 1400 case IPV6CTL_KEEPFAITH: 1401 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_keepfaith); 1402 case IPV6CTL_LOG_INTERVAL: 1403 return sysctl_int(oldp, oldlenp, newp, newlen, 1404 &ip6_log_interval); 1405 case IPV6CTL_HDRNESTLIMIT: 1406 return sysctl_int(oldp, oldlenp, newp, newlen, 1407 &ip6_hdrnestlimit); 1408 case IPV6CTL_DAD_COUNT: 1409 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_dad_count); 1410 case IPV6CTL_AUTO_FLOWLABEL: 1411 return sysctl_int(oldp, oldlenp, newp, newlen, 1412 &ip6_auto_flowlabel); 1413 case IPV6CTL_DEFMCASTHLIM: 1414 return sysctl_int(oldp, oldlenp, newp, newlen, 1415 &ip6_defmcasthlim); 1416 case IPV6CTL_GIF_HLIM: 1417 return sysctl_int(oldp, oldlenp, newp, newlen, 1418 &ip6_gif_hlim); 1419 case IPV6CTL_KAME_VERSION: 1420 return sysctl_rdstring(oldp, oldlenp, newp, __KAME_VERSION); 1421 case IPV6CTL_USE_DEPRECATED: 1422 return sysctl_int(oldp, oldlenp, newp, newlen, 1423 &ip6_use_deprecated); 1424 case IPV6CTL_RR_PRUNE: 1425 return sysctl_int(oldp, oldlenp, newp, newlen, &ip6_rr_prune); 1426 #ifndef INET6_BINDV6ONLY 1427 case IPV6CTL_BINDV6ONLY: 1428 return sysctl_int(oldp, oldlenp, newp, newlen, 1429 &ip6_bindv6only); 1430 #endif 1431 case IPV6CTL_ANONPORTMIN: 1432 old = ip6_anonportmin; 1433 error = sysctl_int(oldp, oldlenp, newp, newlen, 1434 &ip6_anonportmin); 1435 if (ip6_anonportmin >= ip6_anonportmax || ip6_anonportmin < 0 || 1436 ip6_anonportmin > 65535 1437 #ifndef IPNOPRIVPORTS 1438 || ip6_anonportmin < IPV6PORT_RESERVED 1439 #endif 1440 ) { 1441 ip6_anonportmin = old; 1442 return (EINVAL); 1443 } 1444 return (error); 1445 case IPV6CTL_ANONPORTMAX: 1446 old = ip6_anonportmax; 1447 error = sysctl_int(oldp, oldlenp, newp, newlen, 1448 &ip6_anonportmax); 1449 if (ip6_anonportmin >= ip6_anonportmax || ip6_anonportmax < 0 || 1450 ip6_anonportmax > 65535 1451 #ifndef IPNOPRIVPORTS 1452 || ip6_anonportmax < IPV6PORT_RESERVED 1453 #endif 1454 ) { 1455 ip6_anonportmax = old; 1456 return (EINVAL); 1457 } 1458 return (error); 1459 #ifndef IPNOPRIVPORTS 1460 case IPV6CTL_LOWPORTMIN: 1461 old = ip6_lowportmin; 1462 error = sysctl_int(oldp, oldlenp, newp, newlen, 1463 &ip6_lowportmin); 1464 if (ip6_lowportmin >= ip6_lowportmax || 1465 ip6_lowportmin > IPV6PORT_RESERVEDMAX || 1466 ip6_lowportmin < IPV6PORT_RESERVEDMIN) { 1467 ip6_lowportmin = old; 1468 return (EINVAL); 1469 } 1470 return (error); 1471 case IPV6CTL_LOWPORTMAX: 1472 old = ip6_lowportmax; 1473 error = sysctl_int(oldp, oldlenp, newp, newlen, 1474 &ip6_lowportmax); 1475 if (ip6_lowportmin >= ip6_lowportmax || 1476 ip6_lowportmax > IPV6PORT_RESERVEDMAX || 1477 ip6_lowportmax < IPV6PORT_RESERVEDMIN) { 1478 ip6_lowportmax = old; 1479 return (EINVAL); 1480 } 1481 return (error); 1482 #endif 1483 default: 1484 return EOPNOTSUPP; 1485 } 1486 /* NOTREACHED */ 1487 } 1488