1 /* $FreeBSD: src/sys/netinet6/ip6_input.c,v 1.11.2.15 2003/01/24 05:11:35 sam Exp $ */ 2 /* $DragonFly: src/sys/netinet6/ip6_input.c,v 1.38 2008/09/24 14:26:39 sephe Exp $ */ 3 /* $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1988, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 67 */ 68 69 #include "opt_ip6fw.h" 70 #include "opt_inet.h" 71 #include "opt_inet6.h" 72 #include "opt_ipsec.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/malloc.h> 77 #include <sys/mbuf.h> 78 #include <sys/domain.h> 79 #include <sys/protosw.h> 80 #include <sys/socket.h> 81 #include <sys/socketvar.h> 82 #include <sys/errno.h> 83 #include <sys/time.h> 84 #include <sys/kernel.h> 85 #include <sys/syslog.h> 86 #include <sys/proc.h> 87 #include <sys/priv.h> 88 89 #include <net/if.h> 90 #include <net/if_types.h> 91 #include <net/if_dl.h> 92 #include <net/route.h> 93 #include <net/netisr.h> 94 #include <net/pfil.h> 95 96 #include <sys/thread2.h> 97 #include <sys/msgport2.h> 98 #include <net/netmsg2.h> 99 100 #include <netinet/in.h> 101 #include <netinet/in_systm.h> 102 #ifdef INET 103 #include <netinet/ip.h> 104 #include <netinet/ip_icmp.h> 105 #endif /* INET */ 106 #include <netinet/ip6.h> 107 #include <netinet6/in6_var.h> 108 #include <netinet6/ip6_var.h> 109 #include <netinet/in_pcb.h> 110 #include <netinet/icmp6.h> 111 #include <netinet6/scope6_var.h> 112 #include <netinet6/in6_ifattach.h> 113 #include <netinet6/nd6.h> 114 #include <netinet6/in6_prefix.h> 115 116 #ifdef IPSEC 117 #include <netinet6/ipsec.h> 118 #ifdef INET6 119 #include <netinet6/ipsec6.h> 120 #endif 121 #endif 122 123 #ifdef FAST_IPSEC 124 #include <netproto/ipsec/ipsec.h> 125 #include <netproto/ipsec/ipsec6.h> 126 #define IPSEC 127 #endif /* FAST_IPSEC */ 128 129 #include <net/ip6fw/ip6_fw.h> 130 131 #include <netinet6/ip6protosw.h> 132 133 /* we need it for NLOOP. */ 134 #include "use_loop.h" 135 136 #include <net/net_osdep.h> 137 138 extern struct domain inet6domain; 139 extern struct ip6protosw inet6sw[]; 140 141 u_char ip6_protox[IPPROTO_MAX]; 142 struct in6_ifaddr *in6_ifaddr; 143 144 extern struct callout in6_tmpaddrtimer_ch; 145 146 int ip6_forward_srcrt; /* XXX */ 147 int ip6_sourcecheck; /* XXX */ 148 int ip6_sourcecheck_interval; /* XXX */ 149 150 int ip6_ours_check_algorithm; 151 152 struct pfil_head inet6_pfil_hook; 153 154 /* firewall hooks */ 155 ip6_fw_chk_t *ip6_fw_chk_ptr; 156 ip6_fw_ctl_t *ip6_fw_ctl_ptr; 157 int ip6_fw_enable = 1; 158 159 struct ip6stat ip6stat; 160 161 static void ip6_init2 (void *); 162 static struct ip6aux *ip6_setdstifaddr (struct mbuf *, struct in6_ifaddr *); 163 static int ip6_hopopts_input (u_int32_t *, u_int32_t *, struct mbuf **, int *); 164 static void ip6_input(struct netmsg *msg); 165 #ifdef PULLDOWN_TEST 166 static struct mbuf *ip6_pullexthdr (struct mbuf *, size_t, int); 167 #endif 168 static void transport6_processing_handler(netmsg_t netmsg); 169 170 /* 171 * IP6 initialization: fill in IP6 protocol switch table. 172 * All protocols not implemented in kernel go to raw IP6 protocol handler. 173 */ 174 void 175 ip6_init(void) 176 { 177 struct ip6protosw *pr; 178 int i; 179 struct timeval tv; 180 181 #ifdef DIAGNOSTIC 182 if (sizeof(struct protosw) != sizeof(struct ip6protosw)) 183 panic("sizeof(protosw) != sizeof(ip6protosw)"); 184 #endif 185 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 186 if (pr == 0) 187 panic("ip6_init"); 188 for (i = 0; i < IPPROTO_MAX; i++) 189 ip6_protox[i] = pr - inet6sw; 190 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 191 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 192 if (pr->pr_domain->dom_family == PF_INET6 && 193 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 194 ip6_protox[pr->pr_protocol] = pr - inet6sw; 195 196 inet6_pfil_hook.ph_type = PFIL_TYPE_AF; 197 inet6_pfil_hook.ph_af = AF_INET6; 198 if ((i = pfil_head_register(&inet6_pfil_hook)) != 0) { 199 kprintf("%s: WARNING: unable to register pfil hook, " 200 "error %d\n", __func__, i); 201 } 202 203 netisr_register(NETISR_IPV6, ip6_input, NULL); /* XXX cpufn */ 204 scope6_init(); 205 addrsel_policy_init(); 206 nd6_init(); 207 frag6_init(); 208 /* 209 * in many cases, random() here does NOT return random number 210 * as initialization during bootstrap time occur in fixed order. 211 */ 212 microtime(&tv); 213 ip6_flow_seq = krandom() ^ tv.tv_usec; 214 microtime(&tv); 215 ip6_desync_factor = (krandom() ^ tv.tv_usec) % MAX_TEMP_DESYNC_FACTOR; 216 } 217 218 static void 219 ip6_init2(void *dummy) 220 { 221 /* nd6_timer_init */ 222 callout_init(&nd6_timer_ch); 223 callout_reset(&nd6_timer_ch, hz, nd6_timer, NULL); 224 225 /* router renumbering prefix list maintenance */ 226 callout_init(&in6_rr_timer_ch); 227 callout_reset(&in6_rr_timer_ch, hz, in6_rr_timer, NULL); 228 229 /* timer for regeneranation of temporary addresses randomize ID */ 230 callout_init(&in6_tmpaddrtimer_ch); 231 callout_reset(&in6_tmpaddrtimer_ch, 232 (ip6_temp_preferred_lifetime - ip6_desync_factor - 233 ip6_temp_regen_advance) * hz, 234 in6_tmpaddrtimer, NULL); 235 } 236 237 /* cheat */ 238 /* This must be after route_init(), which is now SI_ORDER_THIRD */ 239 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL); 240 241 extern struct route_in6 ip6_forward_rt; 242 243 static 244 void 245 ip6_input(struct netmsg *msg) 246 { 247 struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet; 248 struct ip6_hdr *ip6; 249 int off = sizeof(struct ip6_hdr), nest; 250 u_int32_t plen; 251 u_int32_t rtalert = ~0; 252 int nxt, ours = 0, rh_present = 0; 253 struct ifnet *deliverifp = NULL; 254 struct in6_addr odst; 255 int srcrt = 0; 256 257 #ifdef IPSEC 258 /* 259 * should the inner packet be considered authentic? 260 * see comment in ah4_input(). 261 */ 262 if (m) { 263 m->m_flags &= ~M_AUTHIPHDR; 264 m->m_flags &= ~M_AUTHIPDGM; 265 } 266 #endif 267 268 /* 269 * make sure we don't have onion peering information into m_aux. 270 */ 271 ip6_delaux(m); 272 273 /* 274 * mbuf statistics 275 */ 276 if (m->m_flags & M_EXT) { 277 if (m->m_next) 278 ip6stat.ip6s_mext2m++; 279 else 280 ip6stat.ip6s_mext1++; 281 } else { 282 #define M2MMAX (sizeof(ip6stat.ip6s_m2m)/sizeof(ip6stat.ip6s_m2m[0])) 283 if (m->m_next) { 284 if (m->m_flags & M_LOOP) { 285 ip6stat.ip6s_m2m[loif[0].if_index]++; /* XXX */ 286 } else if (m->m_pkthdr.rcvif->if_index < M2MMAX) 287 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 288 else 289 ip6stat.ip6s_m2m[0]++; 290 } else 291 ip6stat.ip6s_m1++; 292 #undef M2MMAX 293 } 294 295 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 296 ip6stat.ip6s_total++; 297 298 #ifndef PULLDOWN_TEST 299 /* 300 * L2 bridge code and some other code can return mbuf chain 301 * that does not conform to KAME requirement. too bad. 302 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? 303 */ 304 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { 305 struct mbuf *n; 306 307 n = m_getb(m->m_pkthdr.len, MB_DONTWAIT, MT_HEADER, M_PKTHDR); 308 if (n == NULL) 309 goto bad; 310 M_MOVE_PKTHDR(n, m); 311 312 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t)); 313 n->m_len = n->m_pkthdr.len; 314 m_freem(m); 315 m = n; 316 } 317 IP6_EXTHDR_CHECK_VOIDRET(m, 0, sizeof(struct ip6_hdr)); 318 #endif 319 320 if (m->m_len < sizeof(struct ip6_hdr)) { 321 struct ifnet *inifp; 322 inifp = m->m_pkthdr.rcvif; 323 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 324 ip6stat.ip6s_toosmall++; 325 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 326 goto bad2; 327 } 328 } 329 330 ip6 = mtod(m, struct ip6_hdr *); 331 332 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 333 ip6stat.ip6s_badvers++; 334 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 335 goto bad; 336 } 337 338 /* 339 * Run through list of hooks for input packets. 340 * 341 * NB: Beware of the destination address changing 342 * (e.g. by NAT rewriting). When this happens, 343 * tell ip6_forward to do the right thing. 344 */ 345 if (pfil_has_hooks(&inet6_pfil_hook)) { 346 odst = ip6->ip6_dst; 347 if (pfil_run_hooks(&inet6_pfil_hook, &m, 348 m->m_pkthdr.rcvif, PFIL_IN)) { 349 goto bad2; 350 } 351 if (m == NULL) /* consumed by filter */ 352 goto bad2; 353 ip6 = mtod(m, struct ip6_hdr *); 354 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 355 } 356 357 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 358 359 #ifdef ALTQ 360 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 361 /* packet is dropped by traffic conditioner */ 362 return; 363 } 364 #endif 365 366 /* 367 * Check with the firewall... 368 */ 369 if (ip6_fw_enable && ip6_fw_chk_ptr) { 370 u_short port = 0; 371 /* If ipfw says divert, we have to just drop packet */ 372 /* use port as a dummy argument */ 373 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) { 374 m_freem(m); 375 m = NULL; 376 } 377 if (!m) 378 goto bad2; 379 } 380 381 /* 382 * Check against address spoofing/corruption. 383 */ 384 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 385 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 386 /* 387 * XXX: "badscope" is not very suitable for a multicast source. 388 */ 389 ip6stat.ip6s_badscope++; 390 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 391 goto bad; 392 } 393 if ((IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 394 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) && 395 (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 396 ip6stat.ip6s_badscope++; 397 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 398 goto bad; 399 } 400 401 /* 402 * The following check is not documented in specs. A malicious 403 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 404 * and bypass security checks (act as if it was from 127.0.0.1 by using 405 * IPv6 src ::ffff:127.0.0.1). Be cautious. 406 * 407 * This check chokes if we are in an SIIT cloud. As none of BSDs 408 * support IPv4-less kernel compilation, we cannot support SIIT 409 * environment at all. So, it makes more sense for us to reject any 410 * malicious packets for non-SIIT environment, than try to do a 411 * partical support for SIIT environment. 412 */ 413 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 414 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 415 ip6stat.ip6s_badscope++; 416 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 417 goto bad; 418 } 419 #if 0 420 /* 421 * Reject packets with IPv4 compatible addresses (auto tunnel). 422 * 423 * The code forbids auto tunnel relay case in RFC1933 (the check is 424 * stronger than RFC1933). We may want to re-enable it if mech-xx 425 * is revised to forbid relaying case. 426 */ 427 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 428 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 429 ip6stat.ip6s_badscope++; 430 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 431 goto bad; 432 } 433 #endif 434 435 /* drop packets if interface ID portion is already filled */ 436 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 437 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src) && 438 ip6->ip6_src.s6_addr16[1]) { 439 ip6stat.ip6s_badscope++; 440 goto bad; 441 } 442 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst) && 443 ip6->ip6_dst.s6_addr16[1]) { 444 ip6stat.ip6s_badscope++; 445 goto bad; 446 } 447 } 448 449 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 450 ip6->ip6_src.s6_addr16[1] 451 = htons(m->m_pkthdr.rcvif->if_index); 452 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 453 ip6->ip6_dst.s6_addr16[1] 454 = htons(m->m_pkthdr.rcvif->if_index); 455 456 #if 0 /* this case seems to be unnecessary. (jinmei, 20010401) */ 457 /* 458 * We use rt->rt_ifp to determine if the address is ours or not. 459 * If rt_ifp is lo0, the address is ours. 460 * The problem here is, rt->rt_ifp for fe80::%lo0/64 is set to lo0, 461 * so any address under fe80::%lo0/64 will be mistakenly considered 462 * local. The special case is supplied to handle the case properly 463 * by actually looking at interface addresses 464 * (using in6ifa_ifpwithaddr). 465 */ 466 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) && 467 IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 468 if (!in6ifa_ifpwithaddr(m->m_pkthdr.rcvif, &ip6->ip6_dst)) { 469 icmp6_error(m, ICMP6_DST_UNREACH, 470 ICMP6_DST_UNREACH_ADDR, 0); 471 /* m is already freed */ 472 goto bad2; 473 } 474 475 ours = 1; 476 deliverifp = m->m_pkthdr.rcvif; 477 goto hbhcheck; 478 } 479 #endif 480 481 /* 482 * Multicast check 483 */ 484 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 485 struct in6_multi *in6m = 0; 486 487 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 488 /* 489 * See if we belong to the destination multicast group on the 490 * arrival interface. 491 */ 492 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 493 if (in6m) 494 ours = 1; 495 else if (!ip6_mrouter) { 496 ip6stat.ip6s_notmember++; 497 ip6stat.ip6s_cantforward++; 498 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 499 goto bad; 500 } 501 deliverifp = m->m_pkthdr.rcvif; 502 goto hbhcheck; 503 } 504 505 /* 506 * Unicast check 507 */ 508 switch (ip6_ours_check_algorithm) { 509 default: 510 /* 511 * XXX: I intentionally broke our indentation rule here, 512 * since this switch-case is just for measurement and 513 * therefore should soon be removed. 514 */ 515 if (ip6_forward_rt.ro_rt != NULL && 516 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) && 517 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 518 &((struct sockaddr_in6 *)(&ip6_forward_rt.ro_dst))->sin6_addr)) 519 ip6stat.ip6s_forward_cachehit++; 520 else { 521 struct sockaddr_in6 *dst6; 522 523 if (ip6_forward_rt.ro_rt) { 524 /* route is down or destination is different */ 525 ip6stat.ip6s_forward_cachemiss++; 526 RTFREE(ip6_forward_rt.ro_rt); 527 ip6_forward_rt.ro_rt = 0; 528 } 529 530 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 531 dst6 = &ip6_forward_rt.ro_dst; 532 dst6->sin6_len = sizeof(struct sockaddr_in6); 533 dst6->sin6_family = AF_INET6; 534 dst6->sin6_addr = ip6->ip6_dst; 535 536 rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING); 537 } 538 539 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 540 541 /* 542 * Accept the packet if the forwarding interface to the destination 543 * according to the routing table is the loopback interface, 544 * unless the associated route has a gateway. 545 * Note that this approach causes to accept a packet if there is a 546 * route to the loopback interface for the destination of the packet. 547 * But we think it's even useful in some situations, e.g. when using 548 * a special daemon which wants to intercept the packet. 549 * 550 * XXX: some OSes automatically make a cloned route for the destination 551 * of an outgoing packet. If the outgoing interface of the packet 552 * is a loopback one, the kernel would consider the packet to be 553 * accepted, even if we have no such address assinged on the interface. 554 * We check the cloned flag of the route entry to reject such cases, 555 * assuming that route entries for our own addresses are not made by 556 * cloning (it should be true because in6_addloop explicitly installs 557 * the host route). However, we might have to do an explicit check 558 * while it would be less efficient. Or, should we rather install a 559 * reject route for such a case? 560 */ 561 if (ip6_forward_rt.ro_rt && 562 (ip6_forward_rt.ro_rt->rt_flags & 563 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 564 #ifdef RTF_WASCLONED 565 !(ip6_forward_rt.ro_rt->rt_flags & RTF_WASCLONED) && 566 #endif 567 #ifdef RTF_CLONED 568 !(ip6_forward_rt.ro_rt->rt_flags & RTF_CLONED) && 569 #endif 570 #if 0 571 /* 572 * The check below is redundant since the comparison of 573 * the destination and the key of the rtentry has 574 * already done through looking up the routing table. 575 */ 576 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 577 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) 578 #endif 579 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 580 struct in6_ifaddr *ia6 = 581 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 582 583 /* 584 * record address information into m_aux. 585 */ 586 ip6_setdstifaddr(m, ia6); 587 588 /* 589 * packets to a tentative, duplicated, or somehow invalid 590 * address must not be accepted. 591 */ 592 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 593 /* this address is ready */ 594 ours = 1; 595 deliverifp = ia6->ia_ifp; /* correct? */ 596 /* Count the packet in the ip address stats */ 597 ia6->ia_ifa.if_ipackets++; 598 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len; 599 goto hbhcheck; 600 } else { 601 /* address is not ready, so discard the packet. */ 602 nd6log((LOG_INFO, 603 "ip6_input: packet to an unready address %s->%s\n", 604 ip6_sprintf(&ip6->ip6_src), 605 ip6_sprintf(&ip6->ip6_dst))); 606 607 goto bad; 608 } 609 } 610 } /* XXX indentation (see above) */ 611 612 /* 613 * FAITH(Firewall Aided Internet Translator) 614 */ 615 if (ip6_keepfaith) { 616 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 617 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 618 /* XXX do we need more sanity checks? */ 619 ours = 1; 620 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /* faith */ 621 goto hbhcheck; 622 } 623 } 624 625 /* 626 * Now there is no reason to process the packet if it's not our own 627 * and we're not a router. 628 */ 629 if (!ip6_forwarding) { 630 ip6stat.ip6s_cantforward++; 631 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 632 goto bad; 633 } 634 635 hbhcheck: 636 /* 637 * record address information into m_aux, if we don't have one yet. 638 * note that we are unable to record it, if the address is not listed 639 * as our interface address (e.g. multicast addresses, addresses 640 * within FAITH prefixes and such). 641 */ 642 if (deliverifp && !ip6_getdstifaddr(m)) { 643 struct in6_ifaddr *ia6; 644 645 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 646 if (ia6) { 647 if (!ip6_setdstifaddr(m, ia6)) { 648 /* 649 * XXX maybe we should drop the packet here, 650 * as we could not provide enough information 651 * to the upper layers. 652 */ 653 } 654 } 655 } 656 657 /* 658 * Process Hop-by-Hop options header if it's contained. 659 * m may be modified in ip6_hopopts_input(). 660 * If a JumboPayload option is included, plen will also be modified. 661 */ 662 plen = (u_int32_t)ntohs(ip6->ip6_plen); 663 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 664 struct ip6_hbh *hbh; 665 666 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 667 #if 0 /*touches NULL pointer*/ 668 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 669 #endif 670 goto bad2; /* m have already been freed */ 671 } 672 673 /* adjust pointer */ 674 ip6 = mtod(m, struct ip6_hdr *); 675 676 /* 677 * if the payload length field is 0 and the next header field 678 * indicates Hop-by-Hop Options header, then a Jumbo Payload 679 * option MUST be included. 680 */ 681 if (ip6->ip6_plen == 0 && plen == 0) { 682 /* 683 * Note that if a valid jumbo payload option is 684 * contained, ip6_hoptops_input() must set a valid 685 * (non-zero) payload length to the variable plen. 686 */ 687 ip6stat.ip6s_badoptions++; 688 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 689 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 690 icmp6_error(m, ICMP6_PARAM_PROB, 691 ICMP6_PARAMPROB_HEADER, 692 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 693 goto bad2; 694 } 695 #ifndef PULLDOWN_TEST 696 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 697 hbh = (struct ip6_hbh *)(ip6 + 1); 698 #else 699 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 700 sizeof(struct ip6_hbh)); 701 if (hbh == NULL) { 702 ip6stat.ip6s_tooshort++; 703 goto bad2; 704 } 705 #endif 706 nxt = hbh->ip6h_nxt; 707 708 /* 709 * If we are acting as a router and the packet contains a 710 * router alert option, see if we know the option value. 711 * Currently, we only support the option value for MLD, in which 712 * case we should pass the packet to the multicast routing 713 * daemon. 714 */ 715 if (rtalert != ~0 && ip6_forwarding) { 716 switch (rtalert) { 717 case IP6OPT_RTALERT_MLD: 718 ours = 1; 719 break; 720 default: 721 /* 722 * RFC2711 requires unrecognized values must be 723 * silently ignored. 724 */ 725 break; 726 } 727 } 728 } else 729 nxt = ip6->ip6_nxt; 730 731 /* 732 * Check that the amount of data in the buffers 733 * is as at least much as the IPv6 header would have us expect. 734 * Trim mbufs if longer than we expect. 735 * Drop packet if shorter than we expect. 736 */ 737 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 738 ip6stat.ip6s_tooshort++; 739 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 740 goto bad; 741 } 742 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 743 if (m->m_len == m->m_pkthdr.len) { 744 m->m_len = sizeof(struct ip6_hdr) + plen; 745 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 746 } else 747 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 748 } 749 750 /* 751 * Forward if desirable. 752 */ 753 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 754 /* 755 * If we are acting as a multicast router, all 756 * incoming multicast packets are passed to the 757 * kernel-level multicast forwarding function. 758 * The packet is returned (relatively) intact; if 759 * ip6_mforward() returns a non-zero value, the packet 760 * must be discarded, else it may be accepted below. 761 */ 762 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 763 ip6stat.ip6s_cantforward++; 764 goto bad; 765 } 766 if (!ours) 767 goto bad; 768 } else if (!ours) { 769 ip6_forward(m, srcrt); 770 goto bad2; 771 } 772 773 ip6 = mtod(m, struct ip6_hdr *); 774 775 /* 776 * Malicious party may be able to use IPv4 mapped addr to confuse 777 * tcp/udp stack and bypass security checks (act as if it was from 778 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 779 * 780 * For SIIT end node behavior, you may want to disable the check. 781 * However, you will become vulnerable to attacks using IPv4 mapped 782 * source. 783 */ 784 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 785 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 786 ip6stat.ip6s_badscope++; 787 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 788 goto bad; 789 } 790 791 /* 792 * Tell launch routine the next header 793 */ 794 ip6stat.ip6s_delivered++; 795 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 796 nest = 0; 797 798 rh_present = 0; 799 while (nxt != IPPROTO_DONE) { 800 struct ip6protosw *sw6; 801 802 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 803 ip6stat.ip6s_toomanyhdr++; 804 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 805 goto bad; 806 } 807 808 /* 809 * protection against faulty packet - there should be 810 * more sanity checks in header chain processing. 811 */ 812 if (m->m_pkthdr.len < off) { 813 ip6stat.ip6s_tooshort++; 814 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 815 goto bad; 816 } 817 818 #if 0 819 /* 820 * do we need to do it for every header? yeah, other 821 * functions can play with it (like re-allocate and copy). 822 */ 823 mhist = ip6_addaux(m); 824 if (mhist && M_TRAILINGSPACE(mhist) >= sizeof(nxt)) { 825 hist = mtod(mhist, caddr_t) + mhist->m_len; 826 bcopy(&nxt, hist, sizeof(nxt)); 827 mhist->m_len += sizeof(nxt); 828 } else { 829 ip6stat.ip6s_toomanyhdr++; 830 goto bad; 831 } 832 #endif 833 834 if (nxt == IPPROTO_ROUTING) { 835 if (rh_present++) { 836 in6_ifstat_inc(m->m_pkthdr.rcvif, 837 ifs6_in_hdrerr); 838 ip6stat.ip6s_badoptions++; 839 goto bad; 840 } 841 } 842 843 sw6 = &inet6sw[ip6_protox[nxt]]; 844 #ifdef IPSEC 845 /* 846 * enforce IPsec policy checking if we are seeing last header. 847 * note that we do not visit this with protocols with pcb layer 848 * code - like udp/tcp/raw ip. 849 */ 850 if ((sw6->pr_flags & PR_LASTHDR) && ipsec6_in_reject(m, NULL)) { 851 ipsec6stat.in_polvio++; 852 goto bad; 853 } 854 #endif 855 /* 856 * If this is a terminal header forward to the port, otherwise 857 * process synchronously for more headers. 858 */ 859 if (sw6->pr_flags & PR_LASTHDR) { 860 struct netmsg_packet *pmsg; 861 lwkt_port_t port; 862 863 port = sw6->pr_soport(NULL, NULL, &m); 864 KKASSERT(port != NULL); 865 pmsg = &m->m_hdr.mh_netmsg; 866 netmsg_init(&pmsg->nm_netmsg, NULL, 867 &netisr_apanic_rport, 868 0, transport6_processing_handler); 869 pmsg->nm_packet = m; 870 pmsg->nm_nxt = nxt; 871 pmsg->nm_netmsg.nm_lmsg.u.ms_result = off; 872 lwkt_sendmsg(port, &pmsg->nm_netmsg.nm_lmsg); 873 /* done with m */ 874 nxt = IPPROTO_DONE; 875 } else { 876 nxt = sw6->pr_input(&m, &off, nxt); 877 } 878 } 879 goto bad2; 880 bad: 881 m_freem(m); 882 bad2: 883 ; 884 /* msg was embedded in the mbuf, do not reply! */ 885 } 886 887 /* 888 * We have to call the pr_input() function from the correct protocol 889 * thread. The sw6->pr_soport() request at the end of ip6_input() 890 * returns the port and we forward a netmsg to the port to execute 891 * this function. 892 */ 893 static void 894 transport6_processing_handler(netmsg_t netmsg) 895 { 896 struct netmsg_packet *pmsg = (struct netmsg_packet *)netmsg; 897 struct ip6protosw *sw6; 898 int hlen; 899 int nxt; 900 901 sw6 = &inet6sw[ip6_protox[pmsg->nm_nxt]]; 902 hlen = pmsg->nm_netmsg.nm_lmsg.u.ms_result; 903 904 nxt = sw6->pr_input(&pmsg->nm_packet, &hlen, pmsg->nm_nxt); 905 KKASSERT(nxt == IPPROTO_DONE); 906 /* netmsg was embedded in the mbuf, do not reply! */ 907 } 908 909 /* 910 * set/grab in6_ifaddr correspond to IPv6 destination address. 911 * XXX backward compatibility wrapper 912 */ 913 static struct ip6aux * 914 ip6_setdstifaddr(struct mbuf *m, struct in6_ifaddr *ia6) 915 { 916 struct ip6aux *n; 917 918 n = ip6_addaux(m); 919 if (n) 920 n->ip6a_dstia6 = ia6; 921 return n; /* NULL if failed to set */ 922 } 923 924 struct in6_ifaddr * 925 ip6_getdstifaddr(struct mbuf *m) 926 { 927 struct ip6aux *n; 928 929 n = ip6_findaux(m); 930 if (n) 931 return n->ip6a_dstia6; 932 else 933 return NULL; 934 } 935 936 /* 937 * Hop-by-Hop options header processing. If a valid jumbo payload option is 938 * included, the real payload length will be stored in plenp. 939 */ 940 static int 941 ip6_hopopts_input(u_int32_t *plenp, 942 u_int32_t *rtalertp,/* XXX: should be stored more smart way */ 943 struct mbuf **mp, 944 int *offp) 945 { 946 struct mbuf *m = *mp; 947 int off = *offp, hbhlen; 948 struct ip6_hbh *hbh; 949 u_int8_t *opt; 950 951 /* validation of the length of the header */ 952 #ifndef PULLDOWN_TEST 953 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 954 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 955 hbhlen = (hbh->ip6h_len + 1) << 3; 956 957 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 958 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 959 #else 960 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 961 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 962 if (hbh == NULL) { 963 ip6stat.ip6s_tooshort++; 964 return -1; 965 } 966 hbhlen = (hbh->ip6h_len + 1) << 3; 967 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 968 hbhlen); 969 if (hbh == NULL) { 970 ip6stat.ip6s_tooshort++; 971 return -1; 972 } 973 #endif 974 off += hbhlen; 975 hbhlen -= sizeof(struct ip6_hbh); 976 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 977 978 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 979 hbhlen, rtalertp, plenp) < 0) 980 return (-1); 981 982 *offp = off; 983 *mp = m; 984 return (0); 985 } 986 987 /* 988 * Search header for all Hop-by-hop options and process each option. 989 * This function is separate from ip6_hopopts_input() in order to 990 * handle a case where the sending node itself process its hop-by-hop 991 * options header. In such a case, the function is called from ip6_output(). 992 * 993 * The function assumes that hbh header is located right after the IPv6 header 994 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 995 * opthead + hbhlen is located in continuous memory region. 996 */ 997 int 998 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 999 u_int32_t *rtalertp, u_int32_t *plenp) 1000 { 1001 struct ip6_hdr *ip6; 1002 int optlen = 0; 1003 u_int8_t *opt = opthead; 1004 u_int16_t rtalert_val; 1005 u_int32_t jumboplen; 1006 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 1007 1008 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 1009 switch (*opt) { 1010 case IP6OPT_PAD1: 1011 optlen = 1; 1012 break; 1013 case IP6OPT_PADN: 1014 if (hbhlen < IP6OPT_MINLEN) { 1015 ip6stat.ip6s_toosmall++; 1016 goto bad; 1017 } 1018 optlen = *(opt + 1) + 2; 1019 break; 1020 case IP6OPT_RTALERT: 1021 /* XXX may need check for alignment */ 1022 if (hbhlen < IP6OPT_RTALERT_LEN) { 1023 ip6stat.ip6s_toosmall++; 1024 goto bad; 1025 } 1026 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 1027 /* XXX stat */ 1028 icmp6_error(m, ICMP6_PARAM_PROB, 1029 ICMP6_PARAMPROB_HEADER, 1030 erroff + opt + 1 - opthead); 1031 return (-1); 1032 } 1033 optlen = IP6OPT_RTALERT_LEN; 1034 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 1035 *rtalertp = ntohs(rtalert_val); 1036 break; 1037 case IP6OPT_JUMBO: 1038 /* XXX may need check for alignment */ 1039 if (hbhlen < IP6OPT_JUMBO_LEN) { 1040 ip6stat.ip6s_toosmall++; 1041 goto bad; 1042 } 1043 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 1044 /* XXX stat */ 1045 icmp6_error(m, ICMP6_PARAM_PROB, 1046 ICMP6_PARAMPROB_HEADER, 1047 erroff + opt + 1 - opthead); 1048 return (-1); 1049 } 1050 optlen = IP6OPT_JUMBO_LEN; 1051 1052 /* 1053 * IPv6 packets that have non 0 payload length 1054 * must not contain a jumbo payload option. 1055 */ 1056 ip6 = mtod(m, struct ip6_hdr *); 1057 if (ip6->ip6_plen) { 1058 ip6stat.ip6s_badoptions++; 1059 icmp6_error(m, ICMP6_PARAM_PROB, 1060 ICMP6_PARAMPROB_HEADER, 1061 erroff + opt - opthead); 1062 return (-1); 1063 } 1064 1065 /* 1066 * We may see jumbolen in unaligned location, so 1067 * we'd need to perform bcopy(). 1068 */ 1069 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 1070 jumboplen = (u_int32_t)htonl(jumboplen); 1071 1072 #if 1 1073 /* 1074 * if there are multiple jumbo payload options, 1075 * *plenp will be non-zero and the packet will be 1076 * rejected. 1077 * the behavior may need some debate in ipngwg - 1078 * multiple options does not make sense, however, 1079 * there's no explicit mention in specification. 1080 */ 1081 if (*plenp != 0) { 1082 ip6stat.ip6s_badoptions++; 1083 icmp6_error(m, ICMP6_PARAM_PROB, 1084 ICMP6_PARAMPROB_HEADER, 1085 erroff + opt + 2 - opthead); 1086 return (-1); 1087 } 1088 #endif 1089 1090 /* 1091 * jumbo payload length must be larger than 65535. 1092 */ 1093 if (jumboplen <= IPV6_MAXPACKET) { 1094 ip6stat.ip6s_badoptions++; 1095 icmp6_error(m, ICMP6_PARAM_PROB, 1096 ICMP6_PARAMPROB_HEADER, 1097 erroff + opt + 2 - opthead); 1098 return (-1); 1099 } 1100 *plenp = jumboplen; 1101 1102 break; 1103 default: /* unknown option */ 1104 if (hbhlen < IP6OPT_MINLEN) { 1105 ip6stat.ip6s_toosmall++; 1106 goto bad; 1107 } 1108 optlen = ip6_unknown_opt(opt, m, 1109 erroff + opt - opthead); 1110 if (optlen == -1) 1111 return (-1); 1112 optlen += 2; 1113 break; 1114 } 1115 } 1116 1117 return (0); 1118 1119 bad: 1120 m_freem(m); 1121 return (-1); 1122 } 1123 1124 /* 1125 * Unknown option processing. 1126 * The third argument `off' is the offset from the IPv6 header to the option, 1127 * which is necessary if the IPv6 header the and option header and IPv6 header 1128 * is not continuous in order to return an ICMPv6 error. 1129 */ 1130 int 1131 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 1132 { 1133 struct ip6_hdr *ip6; 1134 1135 switch (IP6OPT_TYPE(*optp)) { 1136 case IP6OPT_TYPE_SKIP: /* ignore the option */ 1137 return ((int)*(optp + 1)); 1138 case IP6OPT_TYPE_DISCARD: /* silently discard */ 1139 m_freem(m); 1140 return (-1); 1141 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 1142 ip6stat.ip6s_badoptions++; 1143 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 1144 return (-1); 1145 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 1146 ip6stat.ip6s_badoptions++; 1147 ip6 = mtod(m, struct ip6_hdr *); 1148 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 1149 (m->m_flags & (M_BCAST|M_MCAST))) 1150 m_freem(m); 1151 else 1152 icmp6_error(m, ICMP6_PARAM_PROB, 1153 ICMP6_PARAMPROB_OPTION, off); 1154 return (-1); 1155 } 1156 1157 m_freem(m); /* XXX: NOTREACHED */ 1158 return (-1); 1159 } 1160 1161 /* 1162 * Create the "control" list for this pcb. 1163 * The function will not modify mbuf chain at all. 1164 * 1165 * with KAME mbuf chain restriction: 1166 * The routine will be called from upper layer handlers like tcp6_input(). 1167 * Thus the routine assumes that the caller (tcp6_input) have already 1168 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1169 * very first mbuf on the mbuf chain. 1170 */ 1171 void 1172 ip6_savecontrol(struct inpcb *in6p, struct mbuf **mp, struct ip6_hdr *ip6, 1173 struct mbuf *m) 1174 { 1175 #define IS2292(x, y) ((in6p->in6p_flags & IN6P_RFC2292) ? (x) : (y)) 1176 struct thread *td = curthread; /* XXX */ 1177 int privileged = 0; 1178 int rthdr_exist = 0; 1179 1180 1181 if (priv_check(td, PRIV_ROOT) == 0) 1182 privileged++; 1183 1184 #ifdef SO_TIMESTAMP 1185 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 1186 struct timeval tv; 1187 1188 microtime(&tv); 1189 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1190 SCM_TIMESTAMP, SOL_SOCKET); 1191 if (*mp) { 1192 mp = &(*mp)->m_next; 1193 } 1194 } 1195 #endif 1196 1197 /* RFC 2292 sec. 5 */ 1198 if (in6p->in6p_flags & IN6P_PKTINFO) { 1199 struct in6_pktinfo pi6; 1200 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1201 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 1202 pi6.ipi6_addr.s6_addr16[1] = 0; 1203 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 1204 ? m->m_pkthdr.rcvif->if_index 1205 : 0; 1206 *mp = sbcreatecontrol((caddr_t) &pi6, 1207 sizeof(struct in6_pktinfo), IS2292(IPV6_2292PKTINFO, IPV6_PKTINFO), 1208 IPPROTO_IPV6); 1209 if (*mp) 1210 mp = &(*mp)->m_next; 1211 } 1212 1213 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 1214 int hlim = ip6->ip6_hlim & 0xff; 1215 *mp = sbcreatecontrol((caddr_t) &hlim, 1216 sizeof(int), IS2292(IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), IPPROTO_IPV6); 1217 if (*mp) 1218 mp = &(*mp)->m_next; 1219 } 1220 1221 if ((in6p->in6p_flags & IN6P_TCLASS) != 0) { 1222 u_int32_t flowinfo; 1223 int tclass; 1224 1225 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1226 flowinfo >>= 20; 1227 1228 tclass = flowinfo & 0xff; 1229 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(tclass), 1230 IPV6_TCLASS, IPPROTO_IPV6); 1231 if (*mp) 1232 mp = &(*mp)->m_next; 1233 } 1234 1235 /* 1236 * IPV6_HOPOPTS socket option. We require super-user privilege 1237 * for the option, but it might be too strict, since there might 1238 * be some hop-by-hop options which can be returned to normal user. 1239 * See RFC 2292 section 6. 1240 */ 1241 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 1242 /* 1243 * Check if a hop-by-hop options header is contatined in the 1244 * received packet, and if so, store the options as ancillary 1245 * data. Note that a hop-by-hop options header must be 1246 * just after the IPv6 header, which fact is assured through 1247 * the IPv6 input processing. 1248 */ 1249 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1250 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1251 struct ip6_hbh *hbh; 1252 int hbhlen = 0; 1253 #ifdef PULLDOWN_TEST 1254 struct mbuf *ext; 1255 #endif 1256 1257 #ifndef PULLDOWN_TEST 1258 hbh = (struct ip6_hbh *)(ip6 + 1); 1259 hbhlen = (hbh->ip6h_len + 1) << 3; 1260 #else 1261 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1262 ip6->ip6_nxt); 1263 if (ext == NULL) { 1264 ip6stat.ip6s_tooshort++; 1265 return; 1266 } 1267 hbh = mtod(ext, struct ip6_hbh *); 1268 hbhlen = (hbh->ip6h_len + 1) << 3; 1269 if (hbhlen != ext->m_len) { 1270 m_freem(ext); 1271 ip6stat.ip6s_tooshort++; 1272 return; 1273 } 1274 #endif 1275 1276 /* 1277 * XXX: We copy whole the header even if a jumbo 1278 * payload option is included, which option is to 1279 * be removed before returning in the RFC 2292. 1280 * Note: this constraint is removed in 2292bis. 1281 */ 1282 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1283 IS2292(IPV6_2292HOPOPTS, IPV6_HOPOPTS), IPPROTO_IPV6); 1284 if (*mp) 1285 mp = &(*mp)->m_next; 1286 #ifdef PULLDOWN_TEST 1287 m_freem(ext); 1288 #endif 1289 } 1290 } 1291 1292 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 1293 if ((in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDRDSTOPTS)) != 0) { 1294 int proto, off, nxt; 1295 1296 /* 1297 * go through the header chain to see if a routing header is 1298 * contained in the packet. We need this information to store 1299 * destination options headers (if any) properly. 1300 * XXX: performance issue. We should record this info when 1301 * processing extension headers in incoming routine. 1302 * (todo) use m_aux? 1303 */ 1304 proto = IPPROTO_IPV6; 1305 off = 0; 1306 nxt = -1; 1307 while (1) { 1308 int newoff; 1309 1310 newoff = ip6_nexthdr(m, off, proto, &nxt); 1311 if (newoff < 0) 1312 break; 1313 if (newoff < off) /* invalid, check for safety */ 1314 break; 1315 if ((proto = nxt) == IPPROTO_ROUTING) { 1316 rthdr_exist = 1; 1317 break; 1318 } 1319 off = newoff; 1320 } 1321 } 1322 1323 if ((in6p->in6p_flags & 1324 (IN6P_RTHDR | IN6P_DSTOPTS | IN6P_RTHDRDSTOPTS)) != 0) { 1325 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1326 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1327 1328 /* 1329 * Search for destination options headers or routing 1330 * header(s) through the header chain, and stores each 1331 * header as ancillary data. 1332 * Note that the order of the headers remains in 1333 * the chain of ancillary data. 1334 */ 1335 while (1) { /* is explicit loop prevention necessary? */ 1336 struct ip6_ext *ip6e = NULL; 1337 int elen; 1338 #ifdef PULLDOWN_TEST 1339 struct mbuf *ext = NULL; 1340 #endif 1341 1342 /* 1343 * if it is not an extension header, don't try to 1344 * pull it from the chain. 1345 */ 1346 switch (nxt) { 1347 case IPPROTO_DSTOPTS: 1348 case IPPROTO_ROUTING: 1349 case IPPROTO_HOPOPTS: 1350 case IPPROTO_AH: /* is it possible? */ 1351 break; 1352 default: 1353 goto loopend; 1354 } 1355 1356 #ifndef PULLDOWN_TEST 1357 if (off + sizeof(*ip6e) > m->m_len) 1358 goto loopend; 1359 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1360 if (nxt == IPPROTO_AH) 1361 elen = (ip6e->ip6e_len + 2) << 2; 1362 else 1363 elen = (ip6e->ip6e_len + 1) << 3; 1364 if (off + elen > m->m_len) 1365 goto loopend; 1366 #else 1367 ext = ip6_pullexthdr(m, off, nxt); 1368 if (ext == NULL) { 1369 ip6stat.ip6s_tooshort++; 1370 return; 1371 } 1372 ip6e = mtod(ext, struct ip6_ext *); 1373 if (nxt == IPPROTO_AH) 1374 elen = (ip6e->ip6e_len + 2) << 2; 1375 else 1376 elen = (ip6e->ip6e_len + 1) << 3; 1377 if (elen != ext->m_len) { 1378 m_freem(ext); 1379 ip6stat.ip6s_tooshort++; 1380 return; 1381 } 1382 #endif 1383 1384 switch (nxt) { 1385 case IPPROTO_DSTOPTS: 1386 if ((in6p->in6p_flags & IN6P_DSTOPTS) == 0) 1387 break; 1388 1389 /* 1390 * We also require super-user privilege for 1391 * the option. 1392 * See the comments on IN6_HOPOPTS. 1393 */ 1394 if (!privileged) 1395 break; 1396 1397 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1398 IS2292(IPV6_2292DSTOPTS, IPV6_DSTOPTS), 1399 IPPROTO_IPV6); 1400 if (*mp) 1401 mp = &(*mp)->m_next; 1402 break; 1403 case IPPROTO_ROUTING: 1404 if (!in6p->in6p_flags & IN6P_RTHDR) 1405 break; 1406 1407 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1408 IS2292(IPV6_2292RTHDR, IPV6_RTHDR), 1409 IPPROTO_IPV6); 1410 if (*mp) 1411 mp = &(*mp)->m_next; 1412 break; 1413 case IPPROTO_HOPOPTS: 1414 case IPPROTO_AH: /* is it possible? */ 1415 break; 1416 1417 default: 1418 /* 1419 * other cases have been filtered in the above. 1420 * none will visit this case. here we supply 1421 * the code just in case (nxt overwritten or 1422 * other cases). 1423 */ 1424 #ifdef PULLDOWN_TEST 1425 m_freem(ext); 1426 #endif 1427 goto loopend; 1428 1429 } 1430 1431 /* proceed with the next header. */ 1432 off += elen; 1433 nxt = ip6e->ip6e_nxt; 1434 ip6e = NULL; 1435 #ifdef PULLDOWN_TEST 1436 m_freem(ext); 1437 ext = NULL; 1438 #endif 1439 } 1440 loopend: 1441 ; 1442 } 1443 #undef IS2292 1444 } 1445 1446 void 1447 ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu) 1448 { 1449 struct socket *so; 1450 struct mbuf *m_mtu; 1451 struct ip6_mtuinfo mtuctl; 1452 1453 so = in6p->inp_socket; 1454 1455 if (mtu == NULL) 1456 return; 1457 1458 #ifdef DIAGNOSTIC 1459 if (so == NULL) /* I believe this is impossible */ 1460 panic("ip6_notify_pmtu: socket is NULL"); 1461 #endif 1462 1463 bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */ 1464 mtuctl.ip6m_mtu = *mtu; 1465 mtuctl.ip6m_addr = *dst; 1466 1467 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), 1468 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) 1469 return; 1470 1471 if (sbappendaddr(&so->so_rcv.sb, (struct sockaddr *)dst, NULL, m_mtu) 1472 == 0) { 1473 m_freem(m_mtu); 1474 /* XXX: should count statistics */ 1475 } else 1476 sorwakeup(so); 1477 1478 return; 1479 } 1480 1481 #ifdef PULLDOWN_TEST 1482 /* 1483 * pull single extension header from mbuf chain. returns single mbuf that 1484 * contains the result, or NULL on error. 1485 */ 1486 static struct mbuf * 1487 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1488 { 1489 struct ip6_ext ip6e; 1490 size_t elen; 1491 struct mbuf *n; 1492 1493 #ifdef DIAGNOSTIC 1494 switch (nxt) { 1495 case IPPROTO_DSTOPTS: 1496 case IPPROTO_ROUTING: 1497 case IPPROTO_HOPOPTS: 1498 case IPPROTO_AH: /* is it possible? */ 1499 break; 1500 default: 1501 kprintf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1502 } 1503 #endif 1504 1505 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1506 if (nxt == IPPROTO_AH) 1507 elen = (ip6e.ip6e_len + 2) << 2; 1508 else 1509 elen = (ip6e.ip6e_len + 1) << 3; 1510 1511 n = m_getb(elen, MB_DONTWAIT, MT_DATA, 0); 1512 if (n == NULL) 1513 return NULL; 1514 n->m_len = 0; 1515 1516 if (elen >= M_TRAILINGSPACE(n)) { 1517 m_free(n); 1518 return NULL; 1519 } 1520 1521 m_copydata(m, off, elen, mtod(n, caddr_t)); 1522 n->m_len = elen; 1523 return n; 1524 } 1525 #endif 1526 1527 /* 1528 * Get pointer to the previous header followed by the header 1529 * currently processed. 1530 * XXX: This function supposes that 1531 * M includes all headers, 1532 * the next header field and the header length field of each header 1533 * are valid, and 1534 * the sum of each header length equals to OFF. 1535 * Because of these assumptions, this function must be called very 1536 * carefully. Moreover, it will not be used in the near future when 1537 * we develop `neater' mechanism to process extension headers. 1538 */ 1539 char * 1540 ip6_get_prevhdr(struct mbuf *m, int off) 1541 { 1542 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1543 1544 if (off == sizeof(struct ip6_hdr)) 1545 return (&ip6->ip6_nxt); 1546 else { 1547 int len, nxt; 1548 struct ip6_ext *ip6e = NULL; 1549 1550 nxt = ip6->ip6_nxt; 1551 len = sizeof(struct ip6_hdr); 1552 while (len < off) { 1553 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1554 1555 switch (nxt) { 1556 case IPPROTO_FRAGMENT: 1557 len += sizeof(struct ip6_frag); 1558 break; 1559 case IPPROTO_AH: 1560 len += (ip6e->ip6e_len + 2) << 2; 1561 break; 1562 default: 1563 len += (ip6e->ip6e_len + 1) << 3; 1564 break; 1565 } 1566 nxt = ip6e->ip6e_nxt; 1567 } 1568 if (ip6e) 1569 return (&ip6e->ip6e_nxt); 1570 else 1571 return NULL; 1572 } 1573 } 1574 1575 /* 1576 * get next header offset. m will be retained. 1577 */ 1578 int 1579 ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp) 1580 { 1581 struct ip6_hdr ip6; 1582 struct ip6_ext ip6e; 1583 struct ip6_frag fh; 1584 1585 /* just in case */ 1586 if (m == NULL) 1587 panic("ip6_nexthdr: m == NULL"); 1588 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1589 return -1; 1590 1591 switch (proto) { 1592 case IPPROTO_IPV6: 1593 if (m->m_pkthdr.len < off + sizeof(ip6)) 1594 return -1; 1595 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1596 if (nxtp) 1597 *nxtp = ip6.ip6_nxt; 1598 off += sizeof(ip6); 1599 return off; 1600 1601 case IPPROTO_FRAGMENT: 1602 /* 1603 * terminate parsing if it is not the first fragment, 1604 * it does not make sense to parse through it. 1605 */ 1606 if (m->m_pkthdr.len < off + sizeof(fh)) 1607 return -1; 1608 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1609 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ 1610 if (fh.ip6f_offlg & IP6F_OFF_MASK) 1611 return -1; 1612 if (nxtp) 1613 *nxtp = fh.ip6f_nxt; 1614 off += sizeof(struct ip6_frag); 1615 return off; 1616 1617 case IPPROTO_AH: 1618 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1619 return -1; 1620 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1621 if (nxtp) 1622 *nxtp = ip6e.ip6e_nxt; 1623 off += (ip6e.ip6e_len + 2) << 2; 1624 return off; 1625 1626 case IPPROTO_HOPOPTS: 1627 case IPPROTO_ROUTING: 1628 case IPPROTO_DSTOPTS: 1629 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1630 return -1; 1631 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1632 if (nxtp) 1633 *nxtp = ip6e.ip6e_nxt; 1634 off += (ip6e.ip6e_len + 1) << 3; 1635 return off; 1636 1637 case IPPROTO_NONE: 1638 case IPPROTO_ESP: 1639 case IPPROTO_IPCOMP: 1640 /* give up */ 1641 return -1; 1642 1643 default: 1644 return -1; 1645 } 1646 1647 return -1; 1648 } 1649 1650 /* 1651 * get offset for the last header in the chain. m will be kept untainted. 1652 */ 1653 int 1654 ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp) 1655 { 1656 int newoff; 1657 int nxt; 1658 1659 if (!nxtp) { 1660 nxt = -1; 1661 nxtp = &nxt; 1662 } 1663 while (1) { 1664 newoff = ip6_nexthdr(m, off, proto, nxtp); 1665 if (newoff < 0) 1666 return off; 1667 else if (newoff < off) 1668 return -1; /* invalid */ 1669 else if (newoff == off) 1670 return newoff; 1671 1672 off = newoff; 1673 proto = *nxtp; 1674 } 1675 } 1676 1677 struct ip6aux * 1678 ip6_addaux(struct mbuf *m) 1679 { 1680 struct m_tag *tag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1681 if (!tag) { 1682 tag = m_tag_get(PACKET_TAG_IPV6_INPUT, 1683 sizeof (struct ip6aux), 1684 MB_DONTWAIT); 1685 if (tag) 1686 m_tag_prepend(m, tag); 1687 } 1688 if (tag) 1689 bzero(m_tag_data(tag), sizeof (struct ip6aux)); 1690 return tag ? (struct ip6aux *)m_tag_data(tag) : NULL; 1691 } 1692 1693 struct ip6aux * 1694 ip6_findaux(struct mbuf *m) 1695 { 1696 struct m_tag *tag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1697 return tag ? (struct ip6aux*)(tag+1) : NULL; 1698 } 1699 1700 void 1701 ip6_delaux(struct mbuf *m) 1702 { 1703 struct m_tag *tag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL); 1704 if (tag) 1705 m_tag_delete(m, tag); 1706 } 1707 1708 /* 1709 * System control for IP6 1710 */ 1711 1712 u_char inet6ctlerrmap[PRC_NCMDS] = { 1713 0, 0, 0, 0, 1714 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1715 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1716 EMSGSIZE, EHOSTUNREACH, 0, 0, 1717 0, 0, 0, 0, 1718 ENOPROTOOPT 1719 }; 1720