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 <sys/param.h> 68 #include <sys/systm.h> 69 #include <sys/malloc.h> 70 #include <sys/mbuf.h> 71 #include <sys/domain.h> 72 #include <sys/protosw.h> 73 #include <sys/socket.h> 74 #include <sys/socketvar.h> 75 #include <sys/errno.h> 76 #include <sys/time.h> 77 #include <sys/kernel.h> 78 #include <sys/syslog.h> 79 #include <sys/proc.h> 80 81 #include <net/if.h> 82 #include <net/if_types.h> 83 #include <net/if_dl.h> 84 #include <net/route.h> 85 #include <net/netisr.h> 86 87 #include <netinet/in.h> 88 #include <netinet/in_systm.h> 89 #include <netinet/ip.h> 90 #include <netinet/ip_icmp.h> 91 #include <netinet/in_pcb.h> 92 #include <netinet6/in6_var.h> 93 #include <netinet6/ip6.h> 94 #include <netinet6/ip6_var.h> 95 #include <netinet6/icmp6.h> 96 #include <netinet6/in6_ifattach.h> 97 #include <netinet6/nd6.h> 98 #include <netinet6/in6_prefix.h> 99 100 #ifdef IPV6FIREWALL 101 #include <netinet6/ip6_fw.h> 102 #endif 103 104 #ifdef ALTQ 105 #include <netinet/altq_cdnr.h> 106 #endif 107 108 #include <netinet6/ip6protosw.h> 109 110 /* we need it for NLOOP. */ 111 #include "loop.h" 112 113 #include "faith.h" 114 #include "gif.h" 115 116 #include <net/net_osdep.h> 117 118 extern struct domain inet6domain; 119 extern struct ip6protosw inet6sw[]; 120 121 u_char ip6_protox[IPPROTO_MAX]; 122 static int ip6qmaxlen = IFQ_MAXLEN; 123 struct in6_ifaddr *in6_ifaddr; 124 struct ifqueue ip6intrq; 125 126 int ip6_forward_srcrt; /* XXX */ 127 int ip6_sourcecheck; /* XXX */ 128 int ip6_sourcecheck_interval; /* XXX */ 129 130 #ifdef IPV6FIREWALL 131 /* firewall hooks */ 132 ip6_fw_chk_t *ip6_fw_chk_ptr; 133 ip6_fw_ctl_t *ip6_fw_ctl_ptr; 134 #endif 135 136 struct ip6stat ip6stat; 137 138 static void ip6_init2 __P((void *)); 139 140 static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *)); 141 142 #if defined(PTR) 143 extern int ip6_protocol_tr; 144 145 int ptr_in6 __P((struct mbuf *, struct mbuf **)); 146 extern void ip_forward __P((struct mbuf *, int)); 147 #endif 148 149 /* 150 * IP6 initialization: fill in IP6 protocol switch table. 151 * All protocols not implemented in kernel go to raw IP6 protocol handler. 152 */ 153 void 154 ip6_init() 155 { 156 register struct ip6protosw *pr; 157 register int i; 158 struct timeval tv; 159 160 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 161 if (pr == 0) 162 panic("ip6_init"); 163 for (i = 0; i < IPPROTO_MAX; i++) 164 ip6_protox[i] = pr - inet6sw; 165 for (pr = (struct ip6protosw *)inet6domain.dom_protosw; 166 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) 167 if (pr->pr_domain->dom_family == PF_INET6 && 168 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 169 ip6_protox[pr->pr_protocol] = pr - inet6sw; 170 ip6intrq.ifq_maxlen = ip6qmaxlen; 171 nd6_init(); 172 frag6_init(); 173 #ifdef IPV6FIREWALL 174 ip6_fw_init(); 175 #endif 176 /* 177 * in many cases, random() here does NOT return random number 178 * as initialization during bootstrap time occur in fixed order. 179 */ 180 microtime(&tv); 181 ip6_flow_seq = random() ^ tv.tv_usec; 182 } 183 184 static void 185 ip6_init2(dummy) 186 void *dummy; 187 { 188 int i; 189 int ret; 190 191 /* get EUI64 from somewhere */ 192 ret = in6_ifattach_getifid(NULL); 193 194 /* 195 * to route local address of p2p link to loopback, 196 * assign loopback address first. 197 */ 198 for (i = 0; i < NLOOP; i++) 199 in6_ifattach(&loif[i], IN6_IFT_LOOP, NULL, 0); 200 201 /* attach pseudo interfaces */ 202 if (ret == 0) 203 in6_ifattach_p2p(); 204 205 /* nd6_timer_init */ 206 timeout(nd6_timer, (caddr_t)0, hz); 207 /* router renumbering prefix list maintenance */ 208 timeout(in6_rr_timer, (caddr_t)0, hz); 209 } 210 211 /* cheat */ 212 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_init2, NULL); 213 214 /* 215 * IP6 input interrupt handling. Just pass the packet to ip6_input. 216 */ 217 void 218 ip6intr() 219 { 220 int s; 221 struct mbuf *m; 222 223 for (;;) { 224 s = splimp(); 225 IF_DEQUEUE(&ip6intrq, m); 226 splx(s); 227 if (m == 0) 228 return; 229 ip6_input(m); 230 } 231 } 232 233 NETISR_SET(NETISR_IPV6, ip6intr); 234 235 extern struct route_in6 ip6_forward_rt; 236 237 void 238 ip6_input(m) 239 struct mbuf *m; 240 { 241 struct ip6_hdr *ip6; 242 int off = sizeof(struct ip6_hdr), nest; 243 u_int32_t plen; 244 u_int32_t rtalert = ~0; 245 int nxt, ours = 0; 246 struct ifnet *deliverifp = NULL; 247 248 #ifdef IPSEC 249 /* 250 * should the inner packet be considered authentic? 251 * see comment in ah4_input(). 252 */ 253 if (m) { 254 m->m_flags &= ~M_AUTHIPHDR; 255 m->m_flags &= ~M_AUTHIPDGM; 256 } 257 #endif 258 259 /* 260 * mbuf statistics by kazu 261 */ 262 if (m->m_flags & M_EXT) { 263 if (m->m_next) 264 ip6stat.ip6s_mext2m++; 265 else 266 ip6stat.ip6s_mext1++; 267 } else { 268 if (m->m_next) { 269 if (m->m_flags & M_LOOP) { 270 ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/ 271 } else if (m->m_pkthdr.rcvif->if_index <= 31) 272 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++; 273 else 274 ip6stat.ip6s_m2m[0]++; 275 } else 276 ip6stat.ip6s_m1++; 277 } 278 279 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 280 ip6stat.ip6s_total++; 281 282 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/); 283 284 if (m->m_len < sizeof(struct ip6_hdr)) { 285 struct ifnet *inifp; 286 inifp = m->m_pkthdr.rcvif; 287 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 288 ip6stat.ip6s_toosmall++; 289 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 290 return; 291 } 292 } 293 294 ip6 = mtod(m, struct ip6_hdr *); 295 296 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 297 ip6stat.ip6s_badvers++; 298 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 299 goto bad; 300 } 301 302 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; 303 304 #ifdef IPV6FIREWALL 305 /* 306 * Check with the firewall... 307 */ 308 if (ip6_fw_chk_ptr) { 309 u_short port = 0; 310 /* If ipfw says divert, we have to just drop packet */ 311 /* use port as a dummy argument */ 312 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) { 313 m_freem(m); 314 m = NULL; 315 } 316 if (!m) 317 return; 318 } 319 #endif 320 321 #ifdef ALTQ 322 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 323 /* packet is dropped by traffic conditioner */ 324 return; 325 } 326 #endif 327 328 /* 329 * Scope check 330 */ 331 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 332 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 333 ip6stat.ip6s_badscope++; 334 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 335 goto bad; 336 } 337 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) || 338 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) { 339 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 340 ours = 1; 341 deliverifp = m->m_pkthdr.rcvif; 342 goto hbhcheck; 343 } else { 344 ip6stat.ip6s_badscope++; 345 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 346 goto bad; 347 } 348 } 349 350 if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) { 351 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) { 352 ours = 1; 353 deliverifp = m->m_pkthdr.rcvif; 354 goto hbhcheck; 355 } 356 } else { 357 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 358 ip6->ip6_src.s6_addr16[1] 359 = htons(m->m_pkthdr.rcvif->if_index); 360 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 361 ip6->ip6_dst.s6_addr16[1] 362 = htons(m->m_pkthdr.rcvif->if_index); 363 } 364 365 #if defined(PTR) 366 /* 367 * 368 */ 369 if (ip6_protocol_tr) 370 { 371 struct mbuf *m1 = NULL; 372 373 switch (ptr_in6(m, &m1)) 374 { 375 case IPPROTO_IP: goto mcastcheck; 376 case IPPROTO_IPV4: ip_forward(m1, 0); break; 377 case IPPROTO_IPV6: ip6_forward(m1, 0); break; 378 case IPPROTO_MAX: /* discard this packet */ 379 default: 380 } 381 382 if (m != m1) 383 m_freem(m); 384 385 return; 386 } 387 388 mcastcheck: 389 #endif 390 391 /* 392 * Multicast check 393 */ 394 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 395 struct in6_multi *in6m = 0; 396 397 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 398 /* 399 * See if we belong to the destination multicast group on the 400 * arrival interface. 401 */ 402 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m); 403 if (in6m) 404 ours = 1; 405 else { 406 ip6stat.ip6s_notmember++; 407 ip6stat.ip6s_cantforward++; 408 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 409 goto bad; 410 } 411 deliverifp = m->m_pkthdr.rcvif; 412 goto hbhcheck; 413 } 414 415 /* 416 * Unicast check 417 */ 418 if (ip6_forward_rt.ro_rt == 0 || 419 !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 420 &ip6_forward_rt.ro_dst.sin6_addr)) { 421 if (ip6_forward_rt.ro_rt) { 422 RTFREE(ip6_forward_rt.ro_rt); 423 ip6_forward_rt.ro_rt = 0; 424 } 425 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6)); 426 ip6_forward_rt.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 427 ip6_forward_rt.ro_dst.sin6_family = AF_INET6; 428 ip6_forward_rt.ro_dst.sin6_addr = ip6->ip6_dst; 429 430 rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING); 431 } 432 433 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key)) 434 435 /* 436 * Accept the packet if the forwarding interface to the destination 437 * according to the routing table is the loopback interface, 438 * unless the associated route has a gateway. 439 * Note that this approach causes to accept a packet if there is a 440 * route to the loopback interface for the destination of the packet. 441 * But we think it's even useful in some situations, e.g. when using 442 * a special daemon which wants to intercept the packet. 443 */ 444 if (ip6_forward_rt.ro_rt && 445 (ip6_forward_rt.ro_rt->rt_flags & 446 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST && 447 /* 448 * The comparison of the destination and the key of the rtentry 449 * has already done through looking up the routing table, 450 * so no need to do such a comparison here again. 451 */ 452 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) { 453 struct in6_ifaddr *ia6 = 454 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa; 455 /* packet to tentative address must not be received */ 456 if (ia6->ia6_flags & IN6_IFF_ANYCAST) 457 m->m_flags |= M_ANYCAST6; 458 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { 459 /* this interface is ready */ 460 ours = 1; 461 deliverifp = ia6->ia_ifp; /* correct? */ 462 goto hbhcheck; 463 } else { 464 /* this interface is not ready, fall through */ 465 } 466 } 467 468 /* 469 * FAITH(Firewall Aided Internet Translator) 470 */ 471 #if defined(NFAITH) && 0 < NFAITH 472 if (ip6_keepfaith) { 473 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp 474 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) { 475 /* XXX do we need more sanity checks? */ 476 ours = 1; 477 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/ 478 goto hbhcheck; 479 } 480 } 481 #endif 482 483 /* 484 * Now there is no reason to process the packet if it's not our own 485 * and we're not a router. 486 */ 487 if (!ip6_forwarding) { 488 ip6stat.ip6s_cantforward++; 489 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 490 goto bad; 491 } 492 493 hbhcheck: 494 /* 495 * Process Hop-by-Hop options header if it's contained. 496 * m may be modified in ip6_hopopts_input(). 497 * If a JumboPayload option is included, plen will also be modified. 498 */ 499 plen = (u_int32_t)ntohs(ip6->ip6_plen); 500 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 501 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { 502 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 503 return; /* m have already been freed */ 504 } 505 /* adjust pointer */ 506 ip6 = mtod(m, struct ip6_hdr *); 507 nxt = ((struct ip6_hbh *)(ip6 + 1))->ip6h_nxt; 508 509 /* 510 * accept the packet if a router alert option is included 511 * and we act as an IPv6 router. 512 */ 513 if (rtalert != ~0 && ip6_forwarding) 514 ours = 1; 515 } else 516 nxt = ip6->ip6_nxt; 517 518 /* 519 * Check that the amount of data in the buffers 520 * is as at least much as the IPv6 header would have us expect. 521 * Trim mbufs if longer than we expect. 522 * Drop packet if shorter than we expect. 523 */ 524 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 525 ip6stat.ip6s_tooshort++; 526 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 527 goto bad; 528 } 529 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 530 if (m->m_len == m->m_pkthdr.len) { 531 m->m_len = sizeof(struct ip6_hdr) + plen; 532 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 533 } else 534 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 535 } 536 537 /* 538 * Forward if desirable. 539 */ 540 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 541 if (!ours) { 542 m_freem(m); 543 return; 544 } 545 } else if (!ours) { 546 ip6_forward(m, 0); 547 return; 548 } 549 550 /* 551 * Tell launch routine the next header 552 */ 553 #if defined(__NetBSD__) && defined(IFA_STATS) 554 if (IFA_STATS && deliverifp != NULL) { 555 struct in6_ifaddr *ia6; 556 ip6 = mtod(m, struct ip6_hdr *); 557 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); 558 if (ia6) 559 ia6->ia_ifa.ifa_data.ifad_inbytes += m->m_pkthdr.len; 560 } 561 #endif 562 ip6stat.ip6s_delivered++; 563 in6_ifstat_inc(deliverifp, ifs6_in_deliver); 564 nest = 0; 565 while (nxt != IPPROTO_DONE) { 566 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 567 ip6stat.ip6s_toomanyhdr++; 568 goto bad; 569 } 570 571 /* 572 * protection against faulty packet - there should be 573 * more sanity checks in header chain processing. 574 */ 575 if (m->m_pkthdr.len < off) { 576 ip6stat.ip6s_tooshort++; 577 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 578 goto bad; 579 } 580 581 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 582 } 583 return; 584 bad: 585 m_freem(m); 586 } 587 588 /* 589 * Hop-by-Hop options header processing. If a valid jumbo payload option is 590 * included, the real payload length will be stored in plenp. 591 */ 592 static int 593 ip6_hopopts_input(plenp, rtalertp, mp, offp) 594 u_int32_t *plenp; 595 u_int32_t *rtalertp; /* XXX: should be stored more smart way */ 596 struct mbuf **mp; 597 int *offp; 598 { 599 register struct mbuf *m = *mp; 600 int off = *offp, hbhlen; 601 struct ip6_hbh *hbh; 602 u_int8_t *opt; 603 604 /* validation of the length of the header */ 605 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 606 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 607 hbhlen = (hbh->ip6h_len + 1) << 3; 608 609 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 610 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 611 off += hbhlen; 612 hbhlen -= sizeof(struct ip6_hbh); 613 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); 614 615 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 616 hbhlen, rtalertp, plenp) < 0) 617 return(-1); 618 619 *offp = off; 620 *mp = m; 621 return(0); 622 } 623 624 /* 625 * Search header for all Hop-by-hop options and process each option. 626 * This function is separate from ip6_hopopts_input() in order to 627 * handle a case where the sending node itself process its hop-by-hop 628 * options header. In such a case, the function is called from ip6_output(). 629 */ 630 int 631 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp) 632 struct mbuf *m; 633 u_int8_t *opthead; 634 int hbhlen; 635 u_int32_t *rtalertp; 636 u_int32_t *plenp; 637 { 638 struct ip6_hdr *ip6; 639 int optlen = 0; 640 u_int8_t *opt = opthead; 641 u_int16_t rtalert_val; 642 643 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 644 switch(*opt) { 645 case IP6OPT_PAD1: 646 optlen = 1; 647 break; 648 case IP6OPT_PADN: 649 if (hbhlen < IP6OPT_MINLEN) { 650 ip6stat.ip6s_toosmall++; 651 goto bad; 652 } 653 optlen = *(opt + 1) + 2; 654 break; 655 case IP6OPT_RTALERT: 656 /* XXX may need check for alignment */ 657 if (hbhlen < IP6OPT_RTALERT_LEN) { 658 ip6stat.ip6s_toosmall++; 659 goto bad; 660 } 661 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) 662 /* XXX: should we discard the packet? */ 663 log(LOG_ERR, "length of router alert opt is inconsitent(%d)", 664 *(opt + 1)); 665 optlen = IP6OPT_RTALERT_LEN; 666 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 667 *rtalertp = ntohs(rtalert_val); 668 break; 669 case IP6OPT_JUMBO: 670 /* XXX may need check for alignment */ 671 if (hbhlen < IP6OPT_JUMBO_LEN) { 672 ip6stat.ip6s_toosmall++; 673 goto bad; 674 } 675 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) 676 /* XXX: should we discard the packet? */ 677 log(LOG_ERR, "length of jumbopayload opt " 678 "is inconsistent(%d)", 679 *(opt + 1)); 680 optlen = IP6OPT_JUMBO_LEN; 681 682 bcopy(opt + 2, plenp, sizeof(*plenp)); 683 *plenp = htonl(*plenp); 684 if (*plenp <= IPV6_MAXPACKET) { 685 /* 686 * jumbo payload length must be larger 687 * than 65535 688 */ 689 ip6stat.ip6s_badoptions++; 690 icmp6_error(m, ICMP6_PARAM_PROB, 691 ICMP6_PARAMPROB_HEADER, 692 sizeof(struct ip6_hdr) + 693 sizeof(struct ip6_hbh) + 694 opt + 2 - opthead); 695 return(-1); 696 } 697 698 ip6 = mtod(m, struct ip6_hdr *); 699 if (ip6->ip6_plen) { 700 /* 701 * IPv6 packets that have non 0 payload length 702 * must not contain a jumbo paylod option. 703 */ 704 ip6stat.ip6s_badoptions++; 705 icmp6_error(m, ICMP6_PARAM_PROB, 706 ICMP6_PARAMPROB_HEADER, 707 sizeof(struct ip6_hdr) + 708 sizeof(struct ip6_hbh) + 709 opt - opthead); 710 return(-1); 711 } 712 break; 713 default: /* unknown option */ 714 if (hbhlen < IP6OPT_MINLEN) { 715 ip6stat.ip6s_toosmall++; 716 goto bad; 717 } 718 if ((optlen = ip6_unknown_opt(opt, m, 719 sizeof(struct ip6_hdr) + 720 sizeof(struct ip6_hbh) + 721 opt - opthead)) == -1) 722 return(-1); 723 optlen += 2; 724 break; 725 } 726 } 727 728 return(0); 729 730 bad: 731 m_freem(m); 732 return(-1); 733 } 734 735 /* 736 * Unknown option processing. 737 * The third argument `off' is the offset from the IPv6 header to the option, 738 * which is necessary if the IPv6 header the and option header and IPv6 header 739 * is not continuous in order to return an ICMPv6 error. 740 */ 741 int 742 ip6_unknown_opt(optp, m, off) 743 u_int8_t *optp; 744 struct mbuf *m; 745 int off; 746 { 747 struct ip6_hdr *ip6; 748 749 switch(IP6OPT_TYPE(*optp)) { 750 case IP6OPT_TYPE_SKIP: /* ignore the option */ 751 return((int)*(optp + 1)); 752 case IP6OPT_TYPE_DISCARD: /* silently discard */ 753 m_freem(m); 754 return(-1); 755 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 756 ip6stat.ip6s_badoptions++; 757 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 758 return(-1); 759 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 760 ip6stat.ip6s_badoptions++; 761 ip6 = mtod(m, struct ip6_hdr *); 762 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 763 (m->m_flags & (M_BCAST|M_MCAST))) 764 m_freem(m); 765 else 766 icmp6_error(m, ICMP6_PARAM_PROB, 767 ICMP6_PARAMPROB_OPTION, off); 768 return(-1); 769 } 770 771 m_freem(m); /* XXX: NOTREACHED */ 772 return(-1); 773 } 774 775 /* 776 * Create the "control" list for this pcb 777 */ 778 void 779 ip6_savecontrol(in6p, mp, ip6, m) 780 register struct inpcb *in6p; 781 register struct mbuf **mp; 782 register struct ip6_hdr *ip6; 783 register struct mbuf *m; 784 { 785 struct proc *p = curproc; /* XXX */ 786 int privileged; 787 788 privileged = 0; 789 if (p && !suser(p)) 790 privileged++; 791 792 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) { 793 struct timeval tv; 794 795 microtime(&tv); 796 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 797 SCM_TIMESTAMP, SOL_SOCKET); 798 if (*mp) 799 mp = &(*mp)->m_next; 800 } 801 if (in6p->in6p_flags & IN6P_RECVDSTADDR) { 802 *mp = sbcreatecontrol((caddr_t) &ip6->ip6_dst, 803 sizeof(struct in6_addr), IPV6_RECVDSTADDR, 804 IPPROTO_IPV6); 805 if (*mp) 806 mp = &(*mp)->m_next; 807 } 808 809 /* RFC 2292 sec. 5 */ 810 if (in6p->in6p_flags & IN6P_PKTINFO) { 811 struct in6_pktinfo pi6; 812 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 813 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr)) 814 pi6.ipi6_addr.s6_addr16[1] = 0; 815 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) 816 ? m->m_pkthdr.rcvif->if_index 817 : 0; 818 *mp = sbcreatecontrol((caddr_t) &pi6, 819 sizeof(struct in6_pktinfo), IPV6_PKTINFO, 820 IPPROTO_IPV6); 821 if (*mp) 822 mp = &(*mp)->m_next; 823 } 824 if (in6p->in6p_flags & IN6P_HOPLIMIT) { 825 int hlim = ip6->ip6_hlim & 0xff; 826 *mp = sbcreatecontrol((caddr_t) &hlim, 827 sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6); 828 if (*mp) 829 mp = &(*mp)->m_next; 830 } 831 /* IN6P_NEXTHOP - for outgoing packet only */ 832 833 /* 834 * IPV6_HOPOPTS socket option. We require super-user privilege 835 * for the option, but it might be too strict, since there might 836 * be some hop-by-hop options which can be returned to normal user. 837 * See RFC 2292 section 6. 838 */ 839 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 840 /* 841 * Check if a hop-by-hop options header is contatined in the 842 * received packet, and if so, store the options as ancillary 843 * data. Note that a hop-by-hop options header must be 844 * just after the IPv6 header, which fact is assured through 845 * the IPv6 input processing. 846 */ 847 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 848 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 849 struct ip6_hbh *hbh = (struct ip6_hbh *)(ip6 + 1); 850 851 /* 852 * XXX: We copy whole the header even if a jumbo 853 * payload option is included, which option is to 854 * be removed before returning in the RFC 2292. 855 * But it's too painful operation... 856 */ 857 *mp = sbcreatecontrol((caddr_t)hbh, 858 (hbh->ip6h_len + 1) << 3, 859 IPV6_HOPOPTS, IPPROTO_IPV6); 860 if (*mp) 861 mp = &(*mp)->m_next; 862 } 863 } 864 865 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */ 866 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) { 867 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 868 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);; 869 870 /* 871 * Search for destination options headers or routing 872 * header(s) through the header chain, and stores each 873 * header as ancillary data. 874 * Note that the order of the headers remains in 875 * the chain of ancillary data. 876 */ 877 while(1) { /* is explicit loop prevention necessary? */ 878 struct ip6_ext *ip6e = 879 (struct ip6_ext *)(mtod(m, caddr_t) + off); 880 881 switch(nxt) { 882 case IPPROTO_DSTOPTS: 883 if (!in6p->in6p_flags & IN6P_DSTOPTS) 884 break; 885 886 /* 887 * We also require super-user privilege for 888 * the option. 889 * See the comments on IN6_HOPOPTS. 890 */ 891 if (!privileged) 892 break; 893 894 *mp = sbcreatecontrol((caddr_t)ip6e, 895 (ip6e->ip6e_len + 1) << 3, 896 IPV6_DSTOPTS, 897 IPPROTO_IPV6); 898 if (*mp) 899 mp = &(*mp)->m_next; 900 break; 901 902 case IPPROTO_ROUTING: 903 if (!in6p->in6p_flags & IN6P_RTHDR) 904 break; 905 906 *mp = sbcreatecontrol((caddr_t)ip6e, 907 (ip6e->ip6e_len + 1) << 3, 908 IPV6_RTHDR, 909 IPPROTO_IPV6); 910 if (*mp) 911 mp = &(*mp)->m_next; 912 break; 913 914 case IPPROTO_UDP: 915 case IPPROTO_TCP: 916 case IPPROTO_ICMPV6: 917 default: 918 /* 919 * stop search if we encounter an upper 920 * layer protocol headers. 921 */ 922 goto loopend; 923 924 case IPPROTO_HOPOPTS: 925 case IPPROTO_AH: /* is it possible? */ 926 break; 927 } 928 929 /* proceed with the next header. */ 930 if (nxt == IPPROTO_AH) 931 off += (ip6e->ip6e_len + 2) << 2; 932 else 933 off += (ip6e->ip6e_len + 1) << 3; 934 nxt = ip6e->ip6e_nxt; 935 } 936 loopend: 937 } 938 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) { 939 /* to be done */ 940 } 941 if ((in6p->in6p_flags & IN6P_DSTOPTS) && privileged) { 942 /* to be done */ 943 } 944 /* IN6P_RTHDR - to be done */ 945 } 946 947 /* 948 * Get pointer to the previous header followed by the header 949 * currently processed. 950 * XXX: This function supposes that 951 * M includes all headers, 952 * the next header field and the header length field of each header 953 * are valid, and 954 * the sum of each header length equals to OFF. 955 * Because of these assumptions, this function must be called very 956 * carefully. Moreover, it will not be used in the near future when 957 * we develop `neater' mechanism to process extension headers. 958 */ 959 char * 960 ip6_get_prevhdr(m, off) 961 struct mbuf *m; 962 int off; 963 { 964 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 965 966 if (off == sizeof(struct ip6_hdr)) 967 return(&ip6->ip6_nxt); 968 else { 969 int len, nxt; 970 struct ip6_ext *ip6e = NULL; 971 972 nxt = ip6->ip6_nxt; 973 len = sizeof(struct ip6_hdr); 974 while (len < off) { 975 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 976 977 switch(nxt) { 978 case IPPROTO_FRAGMENT: 979 len += sizeof(struct ip6_frag); 980 break; 981 case IPPROTO_AH: 982 len += (ip6e->ip6e_len + 2) << 2; 983 break; 984 default: 985 len += (ip6e->ip6e_len + 1) << 3; 986 break; 987 } 988 nxt = ip6e->ip6e_nxt; 989 } 990 if (ip6e) 991 return(&ip6e->ip6e_nxt); 992 else 993 return NULL; 994 } 995 } 996 997 /* 998 * System control for IP6 999 */ 1000 1001 u_char inet6ctlerrmap[PRC_NCMDS] = { 1002 0, 0, 0, 0, 1003 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1004 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1005 EMSGSIZE, EHOSTUNREACH, 0, 0, 1006 0, 0, 0, 0, 1007 ENOPROTOOPT 1008 }; 1009