1 /* 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 /* 33 * Copyright (c) 1982, 1986, 1988, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 3. All advertising materials mentioning features or use of this software 45 * must display the following acknowledgement: 46 * This product includes software developed by the University of 47 * California, Berkeley and its contributors. 48 * 4. Neither the name of the University nor the names of its contributors 49 * may be used to endorse or promote products derived from this software 50 * without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 * 64 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 65 */ 66 67 #include "opt_ipsec.h" 68 69 #include <sys/param.h> 70 #include <sys/systm.h> 71 #include <sys/malloc.h> 72 #include <sys/mbuf.h> 73 #include <sys/domain.h> 74 #include <sys/protosw.h> 75 #include <sys/socket.h> 76 #include <sys/socketvar.h> 77 #include <sys/errno.h> 78 #include <sys/time.h> 79 #include <sys/kernel.h> 80 #include <sys/syslog.h> 81 #include <sys/proc.h> 82 83 #include <net/if.h> 84 #include <net/if_types.h> 85 #include <net/if_dl.h> 86 #include <net/route.h> 87 #include <net/netisr.h> 88 89 #include <netinet/in.h> 90 #include <netinet/in_systm.h> 91 #include <netinet/ip.h> 92 #include <netinet/ip_icmp.h> 93 #include <netinet/in_pcb.h> 94 #include <netinet6/in6_var.h> 95 #include <netinet6/ip6.h> 96 #include <netinet6/ip6_var.h> 97 #include <netinet6/icmp6.h> 98 #include <netinet6/in6_ifattach.h> 99 #include <netinet6/nd6.h> 100 #include <netinet6/in6_prefix.h> 101 102 #ifdef IPV6FIREWALL 103 #include <netinet6/ip6_fw.h> 104 #endif 105 106 #ifdef ALTQ 107 #include <netinet/altq_cdnr.h> 108 #endif 109 110 #include <netinet6/ip6protosw.h> 111 112 /* we need it for NLOOP. */ 113 #include "loop.h" 114 115 #include "faith.h" 116 #include "gif.h" 117 118 #include <net/net_osdep.h> 119 120 extern struct domain inet6domain; 121 extern struct ip6protosw inet6sw[]; 122 123 u_char ip6_protox[IPPROTO_MAX]; 124 static int ip6qmaxlen = IFQ_MAXLEN; 125 struct in6_ifaddr *in6_ifaddr; 126 struct ifqueue ip6intrq; 127 128 int ip6_forward_srcrt; /* XXX */ 129 int ip6_sourcecheck; /* XXX */ 130 int ip6_sourcecheck_interval; /* XXX */ 131 132 #ifdef IPV6FIREWALL 133 /* firewall hooks */ 134 ip6_fw_chk_t *ip6_fw_chk_ptr; 135 ip6_fw_ctl_t *ip6_fw_ctl_ptr; 136 #endif 137 138 struct ip6stat ip6stat; 139 140 static void ip6_init2 __P((void *)); 141 142 static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *)); 143 144 #if defined(PTR) 145 extern int ip6_protocol_tr; 146 147 int ptr_in6 __P((struct mbuf *, struct mbuf **)); 148 extern void ip_forward __P((struct mbuf *, int)); 149 #endif 150 151 /* 152 * IP6 initialization: fill in IP6 protocol switch table. 153 * All protocols not implemented in kernel go to raw IP6 protocol handler. 154 */ 155 void 156 ip6_init() 157 { 158 register struct ip6protosw *pr; 159 register int i; 160 struct timeval tv; 161 162 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 163 if (pr == 0) 164 panic("ip6_init"); 165 for (i = 0; i < IPPROTO_MAX; i++) 166 ip6_protox[i] = pr - inet6sw; 167 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 168 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 169 if (pr->pr_domain->dom_family == PF_INET6 && 170 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 171 ip6_protox[pr->pr_protocol] = pr - inet6sw; 172 ip6intrq.ifq_maxlen = ip6qmaxlen; 173 nd6_init(); 174 frag6_init(); 175 #ifdef IPV6FIREWALL 176 ip6_fw_init(); 177 #endif 178 /* 179 * in many cases, random() here does NOT return random number 180 * as initialization during bootstrap time occur in fixed order. 181 */ 182 microtime(&tv); 183 ip6_flow_seq = random() ^ tv.tv_usec; 184 } 185 186 static void 187 ip6_init2(dummy) 188 void *dummy; 189 { 190 int i; 191 int ret; 192 193 /* get EUI64 from somewhere */ 194 ret = in6_ifattach_getifid(NULL); 195 196 /* 197 * to route local address of p2p link to loopback, 198 * assign loopback address first. 199 */ 200 for (i = 0; i < NLOOP; i++) 201 in6_ifattach(&loif[i], IN6_IFT_LOOP, NULL, 0); 202 203 /* attach pseudo interfaces */ 204 if (ret == 0) 205 in6_ifattach_p2p(); 206 207 /* nd6_timer_init */ 208 timeout(nd6_timer, (caddr_t)0, hz); 209 /* router renumbering prefix list maintenance */ 210 timeout(in6_rr_timer, (caddr_t)0, hz); 211 } 212 213 /* cheat */ 214 /* This must be after route_init(), which is now SI_ORDER_THIRD */ 215 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL); 216 217 /* 218 * IP6 input interrupt handling. Just pass the packet to ip6_input. 219 */ 220 void 221 ip6intr() 222 { 223 int s; 224 struct mbuf *m; 225 226 for (;;) { 227 s = splimp(); 228 IF_DEQUEUE(&ip6intrq, m); 229 splx(s); 230 if (m == 0) 231 return; 232 ip6_input(m); 233 } 234 } 235 236 NETISR_SET(NETISR_IPV6, ip6intr); 237 238 extern struct route_in6 ip6_forward_rt; 239 240 void 241 ip6_input(m) 242 struct mbuf *m; 243 { 244 struct ip6_hdr *ip6; 245 int off = sizeof(struct ip6_hdr), nest; 246 u_int32_t plen; 247 u_int32_t rtalert = ~0; 248 int nxt, ours = 0; 249 struct ifnet *deliverifp = NULL; 250 251 #ifdef IPSEC 252 /* 253 * should the inner packet be considered authentic? 254 * see comment in ah4_input(). 255 */ 256 if (m) { 257 m->m_flags &= ~M_AUTHIPHDR; 258 m->m_flags &= ~M_AUTHIPDGM; 259 } 260 #endif 261 262 /* 263 * mbuf statistics by kazu 264 */ 265 if (m->m_flags & M_EXT) { 266 if (m->m_next) 267 ip6stat.ip6s_mext2m++; 268 else 269 ip6stat.ip6s_mext1++; 270 } else { 271 if (m->m_next) { 272 if (m->m_flags & M_LOOP) { 273 ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/ 274 } else if (m->m_pkthdr.rcvif->if_index <= 31) 275 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 276 else 277 ip6stat.ip6s_m2m[0]++; 278 } else 279 ip6stat.ip6s_m1++; 280 } 281 282 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 283 ip6stat.ip6s_total++; 284 285 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/); 286 287 if (m->m_len < sizeof(struct ip6_hdr)) { 288 struct ifnet *inifp; 289 inifp = m->m_pkthdr.rcvif; 290 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 291 ip6stat.ip6s_toosmall++; 292 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 293 return; 294 } 295 } 296 297 ip6 = mtod(m, struct ip6_hdr *); 298 299 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 300 ip6stat.ip6s_badvers++; 301 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 302 goto bad; 303 } 304 305 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 306 307 #ifdef IPV6FIREWALL 308 /* 309 * Check with the firewall... 310 */ 311 if (ip6_fw_chk_ptr) { 312 u_short port = 0; 313 /* If ipfw says divert, we have to just drop packet */ 314 /* use port as a dummy argument */ 315 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) { 316 m_freem(m); 317 m = NULL; 318 } 319 if (!m) 320 return; 321 } 322 #endif 323 324 #ifdef ALTQ 325 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 326 /* packet is dropped by traffic conditioner */ 327 return; 328 } 329 #endif 330 331 /* 332 * Scope check 333 */ 334 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 335 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 336 ip6stat.ip6s_badscope++; 337 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 338 goto bad; 339 } 340 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 341 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 342 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 343 ip6stat.ip6s_badscope++; 344 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 345 goto bad; 346 } 347 } 348 349 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 350 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 351 ours = 1; 352 deliverifp = m->m_pkthdr.rcvif; 353 goto hbhcheck; 354 } 355 } else { 356 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 357 ip6->ip6_src.s6_addr16[1] 358 = htons(m->m_pkthdr.rcvif->if_index); 359 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 360 ip6->ip6_dst.s6_addr16[1] 361 = htons(m->m_pkthdr.rcvif->if_index); 362 } 363 364 #if defined(PTR) 365 /* 366 * 367 */ 368 if (ip6_protocol_tr) 369 { 370 struct mbuf *m1 = NULL; 371 372 switch (ptr_in6(m, &m1)) 373 { 374 case IPPROTO_IP: goto mcastcheck; 375 case IPPROTO_IPV4: ip_forward(m1, 0); break; 376 case IPPROTO_IPV6: ip6_forward(m1, 0); break; 377 case IPPROTO_MAX: /* discard this packet */ 378 default: 379 } 380 381 if (m != m1) 382 m_freem(m); 383 384 return; 385 } 386 387 mcastcheck: 388 #endif 389 390 /* 391 * Multicast check 392 */ 393 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 394 struct in6_multi *in6m = 0; 395 396 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 397 /* 398 * See if we belong to the destination multicast group on the 399 * arrival interface. 400 */ 401 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 402 if (in6m) 403 ours = 1; 404 else { 405 ip6stat.ip6s_notmember++; 406 ip6stat.ip6s_cantforward++; 407 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 408 goto bad; 409 } 410 deliverifp = m->m_pkthdr.rcvif; 411 goto hbhcheck; 412 } 413 414 /* 415 * Unicast check 416 */ 417 if (ip6_forward_rt.ro_rt == 0 || 418 !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 419 &ip6_forward_rt.ro_dst.sin6_addr)) { 420 if (ip6_forward_rt.ro_rt) { 421 RTFREE(ip6_forward_rt.ro_rt); 422 ip6_forward_rt.ro_rt = 0; 423 } 424 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 425 ip6_forward_rt.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 426 ip6_forward_rt.ro_dst.sin6_family = AF_INET6; 427 ip6_forward_rt.ro_dst.sin6_addr = ip6->ip6_dst; 428 429 rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING); 430 } 431 432 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 433 434 /* 435 * Accept the packet if the forwarding interface to the destination 436 * according to the routing table is the loopback interface, 437 * unless the associated route has a gateway. 438 * Note that this approach causes to accept a packet if there is a 439 * route to the loopback interface for the destination of the packet. 440 * But we think it's even useful in some situations, e.g. when using 441 * a special daemon which wants to intercept the packet. 442 */ 443 if (ip6_forward_rt.ro_rt && 444 (ip6_forward_rt.ro_rt->rt_flags & 445 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 446 /* 447 * The comparison of the destination and the key of the rtentry 448 * has already done through looking up the routing table, 449 * so no need to do such a comparison here again. 450 */ 451 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 452 struct in6_ifaddr *ia6 = 453 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 454 /* packet to tentative address must not be received */ 455 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 456 m->m_flags |= M_ANYCAST6; 457 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 458 /* this interface is ready */ 459 ours = 1; 460 deliverifp = ia6->ia_ifp; /* correct? */ 461 goto hbhcheck; 462 } else { 463 /* this interface is not ready, fall through */ 464 } 465 } 466 467 /* 468 * FAITH(Firewall Aided Internet Translator) 469 */ 470 #if defined(NFAITH) && 0 < NFAITH 471 if (ip6_keepfaith) { 472 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 473 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 474 /* XXX do we need more sanity checks? */ 475 ours = 1; 476 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 477 goto hbhcheck; 478 } 479 } 480 #endif 481 482 /* 483 * Now there is no reason to process the packet if it's not our own 484 * and we're not a router. 485 */ 486 if (!ip6_forwarding) { 487 ip6stat.ip6s_cantforward++; 488 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 489 goto bad; 490 } 491 492 hbhcheck: 493 /* 494 * Process Hop-by-Hop options header if it's contained. 495 * m may be modified in ip6_hopopts_input(). 496 * If a JumboPayload option is included, plen will also be modified. 497 */ 498 plen = (u_int32_t)ntohs(ip6->ip6_plen); 499 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 500 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 501 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 502 return; /* m have already been freed */ 503 } 504 /* adjust pointer */ 505 ip6 = mtod(m, struct ip6_hdr *); 506 nxt = ((struct ip6_hbh *)(ip6 + 1))->ip6h_nxt; 507 508 /* 509 * accept the packet if a router alert option is included 510 * and we act as an IPv6 router. 511 */ 512 if (rtalert != ~0 && ip6_forwarding) 513 ours = 1; 514 } else 515 nxt = ip6->ip6_nxt; 516 517 /* 518 * Check that the amount of data in the buffers 519 * is as at least much as the IPv6 header would have us expect. 520 * Trim mbufs if longer than we expect. 521 * Drop packet if shorter than we expect. 522 */ 523 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 524 ip6stat.ip6s_tooshort++; 525 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 526 goto bad; 527 } 528 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 529 if (m->m_len == m->m_pkthdr.len) { 530 m->m_len = sizeof(struct ip6_hdr) + plen; 531 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 532 } else 533 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 534 } 535 536 /* 537 * Forward if desirable. 538 */ 539 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 540 if (!ours) { 541 m_freem(m); 542 return; 543 } 544 } else if (!ours) { 545 ip6_forward(m, 0); 546 return; 547 } 548 549 /* 550 * Tell launch routine the next header 551 */ 552 #if defined(__NetBSD__) && defined(IFA_STATS) 553 if (IFA_STATS && deliverifp != NULL) { 554 struct in6_ifaddr *ia6; 555 ip6 = mtod(m, struct ip6_hdr *); 556 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 557 if (ia6) 558 ia6->ia_ifa.ifa_data.ifad_inbytes += m->m_pkthdr.len; 559 } 560 #endif 561 ip6stat.ip6s_delivered++; 562 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 563 nest = 0; 564 while (nxt != IPPROTO_DONE) { 565 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 566 ip6stat.ip6s_toomanyhdr++; 567 goto bad; 568 } 569 570 /* 571 * protection against faulty packet - there should be 572 * more sanity checks in header chain processing. 573 */ 574 if (m->m_pkthdr.len < off) { 575 ip6stat.ip6s_tooshort++; 576 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 577 goto bad; 578 } 579 580 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 581 } 582 return; 583 bad: 584 m_freem(m); 585 } 586 587 /* 588 * Hop-by-Hop options header processing. If a valid jumbo payload option is 589 * included, the real payload length will be stored in plenp. 590 */ 591 static int 592 ip6_hopopts_input(plenp, rtalertp, mp, offp) 593 u_int32_t *plenp; 594 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 595 struct mbuf **mp; 596 int *offp; 597 { 598 register struct mbuf *m = *mp; 599 int off = *offp, hbhlen; 600 struct ip6_hbh *hbh; 601 u_int8_t *opt; 602 603 /* validation of the length of the header */ 604 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 605 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 606 hbhlen = (hbh->ip6h_len + 1) << 3; 607 608 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 609 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 610 off += hbhlen; 611 hbhlen -= sizeof(struct ip6_hbh); 612 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 613 614 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 615 hbhlen, rtalertp, plenp) < 0) 616 return(-1); 617 618 *offp = off; 619 *mp = m; 620 return(0); 621 } 622 623 /* 624 * Search header for all Hop-by-hop options and process each option. 625 * This function is separate from ip6_hopopts_input() in order to 626 * handle a case where the sending node itself process its hop-by-hop 627 * options header. In such a case, the function is called from ip6_output(). 628 */ 629 int 630 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 631 struct mbuf *m; 632 u_int8_t *opthead; 633 int hbhlen; 634 u_int32_t *rtalertp; 635 u_int32_t *plenp; 636 { 637 struct ip6_hdr *ip6; 638 int optlen = 0; 639 u_int8_t *opt = opthead; 640 u_int16_t rtalert_val; 641 642 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 643 switch(*opt) { 644 case IP6OPT_PAD1: 645 optlen = 1; 646 break; 647 case IP6OPT_PADN: 648 if (hbhlen < IP6OPT_MINLEN) { 649 ip6stat.ip6s_toosmall++; 650 goto bad; 651 } 652 optlen = *(opt + 1) + 2; 653 break; 654 case IP6OPT_RTALERT: 655 /* XXX may need check for alignment */ 656 if (hbhlen < IP6OPT_RTALERT_LEN) { 657 ip6stat.ip6s_toosmall++; 658 goto bad; 659 } 660 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) 661 /* XXX: should we discard the packet? */ 662 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 663 *(opt + 1)); 664 optlen = IP6OPT_RTALERT_LEN; 665 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 666 *rtalertp = ntohs(rtalert_val); 667 break; 668 case IP6OPT_JUMBO: 669 /* XXX may need check for alignment */ 670 if (hbhlen < IP6OPT_JUMBO_LEN) { 671 ip6stat.ip6s_toosmall++; 672 goto bad; 673 } 674 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) 675 /* XXX: should we discard the packet? */ 676 log(LOG_ERR, "length of jumbopayload opt " 677 "is inconsistent(%d)", 678 *(opt + 1)); 679 optlen = IP6OPT_JUMBO_LEN; 680 681 bcopy(opt + 2, plenp, sizeof(*plenp)); 682 *plenp = htonl(*plenp); 683 if (*plenp <= IPV6_MAXPACKET) { 684 /* 685 * jumbo payload length must be larger 686 * than 65535 687 */ 688 ip6stat.ip6s_badoptions++; 689 icmp6_error(m, ICMP6_PARAM_PROB, 690 ICMP6_PARAMPROB_HEADER, 691 sizeof(struct ip6_hdr) + 692 sizeof(struct ip6_hbh) + 693 opt + 2 - opthead); 694 return(-1); 695 } 696 697 ip6 = mtod(m, struct ip6_hdr *); 698 if (ip6->ip6_plen) { 699 /* 700 * IPv6 packets that have non 0 payload length 701 * must not contain a jumbo paylod option. 702 */ 703 ip6stat.ip6s_badoptions++; 704 icmp6_error(m, ICMP6_PARAM_PROB, 705 ICMP6_PARAMPROB_HEADER, 706 sizeof(struct ip6_hdr) + 707 sizeof(struct ip6_hbh) + 708 opt - opthead); 709 return(-1); 710 } 711 break; 712 default: /* unknown option */ 713 if (hbhlen < IP6OPT_MINLEN) { 714 ip6stat.ip6s_toosmall++; 715 goto bad; 716 } 717 if ((optlen = ip6_unknown_opt(opt, m, 718 sizeof(struct ip6_hdr) + 719 sizeof(struct ip6_hbh) + 720 opt - opthead)) == -1) 721 return(-1); 722 optlen += 2; 723 break; 724 } 725 } 726 727 return(0); 728 729 bad: 730 m_freem(m); 731 return(-1); 732 } 733 734 /* 735 * Unknown option processing. 736 * The third argument `off' is the offset from the IPv6 header to the option, 737 * which is necessary if the IPv6 header the and option header and IPv6 header 738 * is not continuous in order to return an ICMPv6 error. 739 */ 740 int 741 ip6_unknown_opt(optp, m, off) 742 u_int8_t *optp; 743 struct mbuf *m; 744 int off; 745 { 746 struct ip6_hdr *ip6; 747 748 switch(IP6OPT_TYPE(*optp)) { 749 case IP6OPT_TYPE_SKIP: /* ignore the option */ 750 return((int)*(optp + 1)); 751 case IP6OPT_TYPE_DISCARD: /* silently discard */ 752 m_freem(m); 753 return(-1); 754 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 755 ip6stat.ip6s_badoptions++; 756 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 757 return(-1); 758 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 759 ip6stat.ip6s_badoptions++; 760 ip6 = mtod(m, struct ip6_hdr *); 761 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 762 (m->m_flags & (M_BCAST|M_MCAST))) 763 m_freem(m); 764 else 765 icmp6_error(m, ICMP6_PARAM_PROB, 766 ICMP6_PARAMPROB_OPTION, off); 767 return(-1); 768 } 769 770 m_freem(m); /* XXX: NOTREACHED */ 771 return(-1); 772 } 773 774 /* 775 * Create the "control" list for this pcb 776 */ 777 void 778 ip6_savecontrol(in6p, mp, ip6, m) 779 register struct inpcb *in6p; 780 register struct mbuf **mp; 781 register struct ip6_hdr *ip6; 782 register struct mbuf *m; 783 { 784 struct proc *p = curproc; /* XXX */ 785 int privileged; 786 787 privileged = 0; 788 if (p && !suser(p)) 789 privileged++; 790 791 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 792 struct timeval tv; 793 794 microtime(&tv); 795 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 796 SCM_TIMESTAMP, SOL_SOCKET); 797 if (*mp) 798 mp = &(*mp)->m_next; 799 } 800 if (in6p->in6p_flags & IN6P_RECVDSTADDR) { 801 *mp = sbcreatecontrol((caddr_t) &ip6->ip6_dst, 802 sizeof(struct in6_addr), IPV6_RECVDSTADDR, 803 IPPROTO_IPV6); 804 if (*mp) 805 mp = &(*mp)->m_next; 806 } 807 808 /* RFC 2292 sec. 5 */ 809 if (in6p->in6p_flags & IN6P_PKTINFO) { 810 struct in6_pktinfo pi6; 811 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 812 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 813 pi6.ipi6_addr.s6_addr16[1] = 0; 814 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 815 ? m->m_pkthdr.rcvif->if_index 816 : 0; 817 *mp = sbcreatecontrol((caddr_t) &pi6, 818 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 819 IPPROTO_IPV6); 820 if (*mp) 821 mp = &(*mp)->m_next; 822 } 823 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 824 int hlim = ip6->ip6_hlim & 0xff; 825 *mp = sbcreatecontrol((caddr_t) &hlim, 826 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 827 if (*mp) 828 mp = &(*mp)->m_next; 829 } 830 /* IN6P_NEXTHOP - for outgoing packet only */ 831 832 /* 833 * IPV6_HOPOPTS socket option. We require super-user privilege 834 * for the option, but it might be too strict, since there might 835 * be some hop-by-hop options which can be returned to normal user. 836 * See RFC 2292 section 6. 837 */ 838 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 839 /* 840 * Check if a hop-by-hop options header is contatined in the 841 * received packet, and if so, store the options as ancillary 842 * data. Note that a hop-by-hop options header must be 843 * just after the IPv6 header, which fact is assured through 844 * the IPv6 input processing. 845 */ 846 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 847 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 848 struct ip6_hbh *hbh = (struct ip6_hbh *)(ip6 + 1); 849 850 /* 851 * XXX: We copy whole the header even if a jumbo 852 * payload option is included, which option is to 853 * be removed before returning in the RFC 2292. 854 * But it's too painful operation... 855 */ 856 *mp = sbcreatecontrol((caddr_t)hbh, 857 (hbh->ip6h_len + 1) << 3, 858 IPV6_HOPOPTS, IPPROTO_IPV6); 859 if (*mp) 860 mp = &(*mp)->m_next; 861 } 862 } 863 864 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 865 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 866 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 867 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 868 869 /* 870 * Search for destination options headers or routing 871 * header(s) through the header chain, and stores each 872 * header as ancillary data. 873 * Note that the order of the headers remains in 874 * the chain of ancillary data. 875 */ 876 while(1) { /* is explicit loop prevention necessary? */ 877 struct ip6_ext *ip6e = 878 (struct ip6_ext *)(mtod(m, caddr_t) + off); 879 880 switch(nxt) { 881 case IPPROTO_DSTOPTS: 882 if (!in6p->in6p_flags & IN6P_DSTOPTS) 883 break; 884 885 /* 886 * We also require super-user privilege for 887 * the option. 888 * See the comments on IN6_HOPOPTS. 889 */ 890 if (!privileged) 891 break; 892 893 *mp = sbcreatecontrol((caddr_t)ip6e, 894 (ip6e->ip6e_len + 1) << 3, 895 IPV6_DSTOPTS, 896 IPPROTO_IPV6); 897 if (*mp) 898 mp = &(*mp)->m_next; 899 break; 900 901 case IPPROTO_ROUTING: 902 if (!in6p->in6p_flags & IN6P_RTHDR) 903 break; 904 905 *mp = sbcreatecontrol((caddr_t)ip6e, 906 (ip6e->ip6e_len + 1) << 3, 907 IPV6_RTHDR, 908 IPPROTO_IPV6); 909 if (*mp) 910 mp = &(*mp)->m_next; 911 break; 912 913 case IPPROTO_UDP: 914 case IPPROTO_TCP: 915 case IPPROTO_ICMPV6: 916 default: 917 /* 918 * stop search if we encounter an upper 919 * layer protocol headers. 920 */ 921 goto loopend; 922 923 case IPPROTO_HOPOPTS: 924 case IPPROTO_AH: /* is it possible? */ 925 break; 926 } 927 928 /* proceed with the next header. */ 929 if (nxt == IPPROTO_AH) 930 off += (ip6e->ip6e_len + 2) << 2; 931 else 932 off += (ip6e->ip6e_len + 1) << 3; 933 nxt = ip6e->ip6e_nxt; 934 } 935 loopend: 936 } 937 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 938 /* to be done */ 939 } 940 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 941 /* to be done */ 942 } 943 /* IN6P_RTHDR - to be done */ 944 } 945 946 /* 947 * Get pointer to the previous header followed by the header 948 * currently processed. 949 * XXX: This function supposes that 950 * M includes all headers, 951 * the next header field and the header length field of each header 952 * are valid, and 953 * the sum of each header length equals to OFF. 954 * Because of these assumptions, this function must be called very 955 * carefully. Moreover, it will not be used in the near future when 956 * we develop `neater' mechanism to process extension headers. 957 */ 958 char * 959 ip6_get_prevhdr(m, off) 960 struct mbuf *m; 961 int off; 962 { 963 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 964 965 if (off == sizeof(struct ip6_hdr)) 966 return(&ip6->ip6_nxt); 967 else { 968 int len, nxt; 969 struct ip6_ext *ip6e = NULL; 970 971 nxt = ip6->ip6_nxt; 972 len = sizeof(struct ip6_hdr); 973 while (len < off) { 974 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 975 976 switch(nxt) { 977 case IPPROTO_FRAGMENT: 978 len += sizeof(struct ip6_frag); 979 break; 980 case IPPROTO_AH: 981 len += (ip6e->ip6e_len + 2) << 2; 982 break; 983 default: 984 len += (ip6e->ip6e_len + 1) << 3; 985 break; 986 } 987 nxt = ip6e->ip6e_nxt; 988 } 989 if (ip6e) 990 return(&ip6e->ip6e_nxt); 991 else 992 return NULL; 993 } 994 } 995 996 /* 997 * System control for IP6 998 */ 999 1000 u_char inet6ctlerrmap[PRC_NCMDS] = { 1001 0, 0, 0, 0, 1002 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1003 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1004 EMSGSIZE, EHOSTUNREACH, 0, 0, 1005 0, 0, 0, 0, 1006 ENOPROTOOPT 1007 }; 1008