ip_input.c revision 1.161
1/* $NetBSD: ip_input.c,v 1.161 2002/11/12 01:38:09 itojun Exp $ */ 2 3/* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32/*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69/* 70 * Copyright (c) 1982, 1986, 1988, 1993 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. All advertising materials mentioning features or use of this software 82 * must display the following acknowledgement: 83 * This product includes software developed by the University of 84 * California, Berkeley and its contributors. 85 * 4. Neither the name of the University nor the names of its contributors 86 * may be used to endorse or promote products derived from this software 87 * without specific prior written permission. 88 * 89 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 90 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 91 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 92 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 93 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 94 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 95 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 96 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 97 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 99 * SUCH DAMAGE. 100 * 101 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 102 */ 103 104#include <sys/cdefs.h> 105__KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.161 2002/11/12 01:38:09 itojun Exp $"); 106 107#include "opt_gateway.h" 108#include "opt_pfil_hooks.h" 109#include "opt_ipsec.h" 110#include "opt_mrouting.h" 111#include "opt_inet_csum.h" 112 113#include <sys/param.h> 114#include <sys/systm.h> 115#include <sys/malloc.h> 116#include <sys/mbuf.h> 117#include <sys/domain.h> 118#include <sys/protosw.h> 119#include <sys/socket.h> 120#include <sys/socketvar.h> 121#include <sys/errno.h> 122#include <sys/time.h> 123#include <sys/kernel.h> 124#include <sys/pool.h> 125#include <sys/sysctl.h> 126 127#include <net/if.h> 128#include <net/if_dl.h> 129#include <net/route.h> 130#include <net/pfil.h> 131 132#include <netinet/in.h> 133#include <netinet/in_systm.h> 134#include <netinet/ip.h> 135#include <netinet/in_pcb.h> 136#include <netinet/in_var.h> 137#include <netinet/ip_var.h> 138#include <netinet/ip_icmp.h> 139/* just for gif_ttl */ 140#include <netinet/in_gif.h> 141#include "gif.h" 142#include <net/if_gre.h> 143#include "gre.h" 144 145#ifdef MROUTING 146#include <netinet/ip_mroute.h> 147#endif 148 149#ifdef IPSEC 150#include <netinet6/ipsec.h> 151#include <netkey/key.h> 152#endif 153 154#ifndef IPFORWARDING 155#ifdef GATEWAY 156#define IPFORWARDING 1 /* forward IP packets not for us */ 157#else /* GATEWAY */ 158#define IPFORWARDING 0 /* don't forward IP packets not for us */ 159#endif /* GATEWAY */ 160#endif /* IPFORWARDING */ 161#ifndef IPSENDREDIRECTS 162#define IPSENDREDIRECTS 1 163#endif 164#ifndef IPFORWSRCRT 165#define IPFORWSRCRT 1 /* forward source-routed packets */ 166#endif 167#ifndef IPALLOWSRCRT 168#define IPALLOWSRCRT 1 /* allow source-routed packets */ 169#endif 170#ifndef IPMTUDISC 171#define IPMTUDISC 1 172#endif 173#ifndef IPMTUDISCTIMEOUT 174#define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 175#endif 176 177/* 178 * Note: DIRECTED_BROADCAST is handled this way so that previous 179 * configuration using this option will Just Work. 180 */ 181#ifndef IPDIRECTEDBCAST 182#ifdef DIRECTED_BROADCAST 183#define IPDIRECTEDBCAST 1 184#else 185#define IPDIRECTEDBCAST 0 186#endif /* DIRECTED_BROADCAST */ 187#endif /* IPDIRECTEDBCAST */ 188int ipforwarding = IPFORWARDING; 189int ipsendredirects = IPSENDREDIRECTS; 190int ip_defttl = IPDEFTTL; 191int ip_forwsrcrt = IPFORWSRCRT; 192int ip_directedbcast = IPDIRECTEDBCAST; 193int ip_allowsrcrt = IPALLOWSRCRT; 194int ip_mtudisc = IPMTUDISC; 195int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 196#ifdef DIAGNOSTIC 197int ipprintfs = 0; 198#endif 199 200struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 201 202extern struct domain inetdomain; 203int ipqmaxlen = IFQ_MAXLEN; 204u_long in_ifaddrhash; /* size of hash table - 1 */ 205int in_ifaddrentries; /* total number of addrs */ 206struct in_ifaddrhead in_ifaddr; 207struct in_ifaddrhashhead *in_ifaddrhashtbl; 208struct ifqueue ipintrq; 209struct ipstat ipstat; 210u_int16_t ip_id; 211 212#ifdef PFIL_HOOKS 213struct pfil_head inet_pfil_hook; 214#endif 215 216struct ipqhead ipq; 217int ipq_locked; 218int ip_nfragpackets = 0; 219int ip_maxfragpackets = 200; 220 221static __inline int ipq_lock_try __P((void)); 222static __inline void ipq_unlock __P((void)); 223 224static __inline int 225ipq_lock_try() 226{ 227 int s; 228 229 /* 230 * Use splvm() -- we're blocking things that would cause 231 * mbuf allocation. 232 */ 233 s = splvm(); 234 if (ipq_locked) { 235 splx(s); 236 return (0); 237 } 238 ipq_locked = 1; 239 splx(s); 240 return (1); 241} 242 243static __inline void 244ipq_unlock() 245{ 246 int s; 247 248 s = splvm(); 249 ipq_locked = 0; 250 splx(s); 251} 252 253#ifdef DIAGNOSTIC 254#define IPQ_LOCK() \ 255do { \ 256 if (ipq_lock_try() == 0) { \ 257 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 258 panic("ipq_lock"); \ 259 } \ 260} while (/*CONSTCOND*/ 0) 261#define IPQ_LOCK_CHECK() \ 262do { \ 263 if (ipq_locked == 0) { \ 264 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 265 panic("ipq lock check"); \ 266 } \ 267} while (/*CONSTCOND*/ 0) 268#else 269#define IPQ_LOCK() (void) ipq_lock_try() 270#define IPQ_LOCK_CHECK() /* nothing */ 271#endif 272 273#define IPQ_UNLOCK() ipq_unlock() 274 275struct pool ipqent_pool; 276 277#ifdef INET_CSUM_COUNTERS 278#include <sys/device.h> 279 280struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 281 NULL, "inet", "hwcsum bad"); 282struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 283 NULL, "inet", "hwcsum ok"); 284struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 285 NULL, "inet", "swcsum"); 286 287#define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 288 289#else 290 291#define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 292 293#endif /* INET_CSUM_COUNTERS */ 294 295/* 296 * We need to save the IP options in case a protocol wants to respond 297 * to an incoming packet over the same route if the packet got here 298 * using IP source routing. This allows connection establishment and 299 * maintenance when the remote end is on a network that is not known 300 * to us. 301 */ 302int ip_nhops = 0; 303static struct ip_srcrt { 304 struct in_addr dst; /* final destination */ 305 char nop; /* one NOP to align */ 306 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 307 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 308} ip_srcrt; 309 310static void save_rte __P((u_char *, struct in_addr)); 311 312/* 313 * IP initialization: fill in IP protocol switch table. 314 * All protocols not implemented in kernel go to raw IP protocol handler. 315 */ 316void 317ip_init() 318{ 319 struct protosw *pr; 320 int i; 321 322 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 323 NULL); 324 325 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 326 if (pr == 0) 327 panic("ip_init"); 328 for (i = 0; i < IPPROTO_MAX; i++) 329 ip_protox[i] = pr - inetsw; 330 for (pr = inetdomain.dom_protosw; 331 pr < inetdomain.dom_protoswNPROTOSW; pr++) 332 if (pr->pr_domain->dom_family == PF_INET && 333 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 334 ip_protox[pr->pr_protocol] = pr - inetsw; 335 LIST_INIT(&ipq); 336 ip_id = time.tv_sec & 0xffff; 337 ipintrq.ifq_maxlen = ipqmaxlen; 338 TAILQ_INIT(&in_ifaddr); 339 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR, 340 M_WAITOK, &in_ifaddrhash); 341 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 342#ifdef GATEWAY 343 ipflow_init(); 344#endif 345 346#ifdef PFIL_HOOKS 347 /* Register our Packet Filter hook. */ 348 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 349 inet_pfil_hook.ph_af = AF_INET; 350 i = pfil_head_register(&inet_pfil_hook); 351 if (i != 0) 352 printf("ip_init: WARNING: unable to register pfil hook, " 353 "error %d\n", i); 354#endif /* PFIL_HOOKS */ 355 356#ifdef INET_CSUM_COUNTERS 357 evcnt_attach_static(&ip_hwcsum_bad); 358 evcnt_attach_static(&ip_hwcsum_ok); 359 evcnt_attach_static(&ip_swcsum); 360#endif /* INET_CSUM_COUNTERS */ 361} 362 363struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 364struct route ipforward_rt; 365 366/* 367 * IP software interrupt routine 368 */ 369void 370ipintr() 371{ 372 int s; 373 struct mbuf *m; 374 375 while (1) { 376 s = splnet(); 377 IF_DEQUEUE(&ipintrq, m); 378 splx(s); 379 if (m == 0) 380 return; 381 ip_input(m); 382 } 383} 384 385/* 386 * Ip input routine. Checksum and byte swap header. If fragmented 387 * try to reassemble. Process options. Pass to next level. 388 */ 389void 390ip_input(struct mbuf *m) 391{ 392 struct ip *ip = NULL; 393 struct ipq *fp; 394 struct in_ifaddr *ia; 395 struct ifaddr *ifa; 396 struct ipqent *ipqe; 397 int hlen = 0, mff, len; 398 int downmatch; 399 400#ifdef DIAGNOSTIC 401 if ((m->m_flags & M_PKTHDR) == 0) 402 panic("ipintr no HDR"); 403#endif 404#ifdef IPSEC 405 /* 406 * should the inner packet be considered authentic? 407 * see comment in ah4_input(). 408 */ 409 if (m) { 410 m->m_flags &= ~M_AUTHIPHDR; 411 m->m_flags &= ~M_AUTHIPDGM; 412 } 413#endif 414 /* 415 * If no IP addresses have been set yet but the interfaces 416 * are receiving, can't do anything with incoming packets yet. 417 */ 418 if (TAILQ_FIRST(&in_ifaddr) == 0) 419 goto bad; 420 ipstat.ips_total++; 421 /* 422 * If the IP header is not aligned, slurp it up into a new 423 * mbuf with space for link headers, in the event we forward 424 * it. Otherwise, if it is aligned, make sure the entire 425 * base IP header is in the first mbuf of the chain. 426 */ 427 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) { 428 if ((m = m_copyup(m, sizeof(struct ip), 429 (max_linkhdr + 3) & ~3)) == NULL) { 430 /* XXXJRT new stat, please */ 431 ipstat.ips_toosmall++; 432 return; 433 } 434 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 435 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 436 ipstat.ips_toosmall++; 437 return; 438 } 439 } 440 ip = mtod(m, struct ip *); 441 if (ip->ip_v != IPVERSION) { 442 ipstat.ips_badvers++; 443 goto bad; 444 } 445 hlen = ip->ip_hl << 2; 446 if (hlen < sizeof(struct ip)) { /* minimum header length */ 447 ipstat.ips_badhlen++; 448 goto bad; 449 } 450 if (hlen > m->m_len) { 451 if ((m = m_pullup(m, hlen)) == 0) { 452 ipstat.ips_badhlen++; 453 return; 454 } 455 ip = mtod(m, struct ip *); 456 } 457 458 /* 459 * RFC1122: packets with a multicast source address are 460 * not allowed. 461 */ 462 if (IN_MULTICAST(ip->ip_src.s_addr)) { 463 ipstat.ips_badaddr++; 464 goto bad; 465 } 466 467 /* 127/8 must not appear on wire - RFC1122 */ 468 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 469 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 470 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 471 ipstat.ips_badaddr++; 472 goto bad; 473 } 474 } 475 476 switch (m->m_pkthdr.csum_flags & 477 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 478 M_CSUM_IPv4_BAD)) { 479 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 480 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 481 goto badcsum; 482 483 case M_CSUM_IPv4: 484 /* Checksum was okay. */ 485 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 486 break; 487 488 default: 489 /* Must compute it ourselves. */ 490 INET_CSUM_COUNTER_INCR(&ip_swcsum); 491 if (in_cksum(m, hlen) != 0) 492 goto bad; 493 break; 494 } 495 496 /* Retrieve the packet length. */ 497 len = ntohs(ip->ip_len); 498 499 /* 500 * Check for additional length bogosity 501 */ 502 if (len < hlen) { 503 ipstat.ips_badlen++; 504 goto bad; 505 } 506 507 /* 508 * Check that the amount of data in the buffers 509 * is as at least much as the IP header would have us expect. 510 * Trim mbufs if longer than we expect. 511 * Drop packet if shorter than we expect. 512 */ 513 if (m->m_pkthdr.len < len) { 514 ipstat.ips_tooshort++; 515 goto bad; 516 } 517 if (m->m_pkthdr.len > len) { 518 if (m->m_len == m->m_pkthdr.len) { 519 m->m_len = len; 520 m->m_pkthdr.len = len; 521 } else 522 m_adj(m, len - m->m_pkthdr.len); 523 } 524 525#ifdef IPSEC 526 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 527 m->m_flags &= ~M_CANFASTFWD; 528#else 529 /* 530 * Assume that we can create a fast-forward IP flow entry 531 * based on this packet. 532 */ 533 m->m_flags |= M_CANFASTFWD; 534#endif 535 536#ifdef PFIL_HOOKS 537 /* 538 * Run through list of hooks for input packets. If there are any 539 * filters which require that additional packets in the flow are 540 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 541 * Note that filters must _never_ set this flag, as another filter 542 * in the list may have previously cleared it. 543 */ 544 /* 545 * let ipfilter look at packet on the wire, 546 * not the decapsulated packet. 547 */ 548#ifdef IPSEC 549 if (!ipsec_getnhist(m)) 550#else 551 if (1) 552#endif 553 { 554 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 555 PFIL_IN) != 0) 556 return; 557 if (m == NULL) 558 return; 559 ip = mtod(m, struct ip *); 560 hlen = ip->ip_hl << 2; 561 } 562#endif /* PFIL_HOOKS */ 563 564#ifdef ALTQ 565 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 566 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 567 /* packet dropped by traffic conditioner */ 568 return; 569 } 570#endif 571 572 /* 573 * Process options and, if not destined for us, 574 * ship it on. ip_dooptions returns 1 when an 575 * error was detected (causing an icmp message 576 * to be sent and the original packet to be freed). 577 */ 578 ip_nhops = 0; /* for source routed packets */ 579 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 580 return; 581 582 /* 583 * Check our list of addresses, to see if the packet is for us. 584 * 585 * Traditional 4.4BSD did not consult IFF_UP at all. 586 * The behavior here is to treat addresses on !IFF_UP interface 587 * as not mine. 588 */ 589 downmatch = 0; 590 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 591 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 592 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 593 break; 594 else 595 downmatch++; 596 } 597 } 598 if (ia != NULL) 599 goto ours; 600 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 601 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) { 602 if (ifa->ifa_addr->sa_family != AF_INET) 603 continue; 604 ia = ifatoia(ifa); 605 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 606 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 607 /* 608 * Look for all-0's host part (old broadcast addr), 609 * either for subnet or net. 610 */ 611 ip->ip_dst.s_addr == ia->ia_subnet || 612 ip->ip_dst.s_addr == ia->ia_net) 613 goto ours; 614 /* 615 * An interface with IP address zero accepts 616 * all packets that arrive on that interface. 617 */ 618 if (in_nullhost(ia->ia_addr.sin_addr)) 619 goto ours; 620 } 621 } 622 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 623 struct in_multi *inm; 624#ifdef MROUTING 625 extern struct socket *ip_mrouter; 626 627 if (M_READONLY(m)) { 628 if ((m = m_pullup(m, hlen)) == 0) { 629 ipstat.ips_toosmall++; 630 return; 631 } 632 ip = mtod(m, struct ip *); 633 } 634 635 if (ip_mrouter) { 636 /* 637 * If we are acting as a multicast router, all 638 * incoming multicast packets are passed to the 639 * kernel-level multicast forwarding function. 640 * The packet is returned (relatively) intact; if 641 * ip_mforward() returns a non-zero value, the packet 642 * must be discarded, else it may be accepted below. 643 * 644 * (The IP ident field is put in the same byte order 645 * as expected when ip_mforward() is called from 646 * ip_output().) 647 */ 648 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 649 ipstat.ips_cantforward++; 650 m_freem(m); 651 return; 652 } 653 654 /* 655 * The process-level routing demon needs to receive 656 * all multicast IGMP packets, whether or not this 657 * host belongs to their destination groups. 658 */ 659 if (ip->ip_p == IPPROTO_IGMP) 660 goto ours; 661 ipstat.ips_forward++; 662 } 663#endif 664 /* 665 * See if we belong to the destination multicast group on the 666 * arrival interface. 667 */ 668 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 669 if (inm == NULL) { 670 ipstat.ips_cantforward++; 671 m_freem(m); 672 return; 673 } 674 goto ours; 675 } 676 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 677 in_nullhost(ip->ip_dst)) 678 goto ours; 679 680 /* 681 * Not for us; forward if possible and desirable. 682 */ 683 if (ipforwarding == 0) { 684 ipstat.ips_cantforward++; 685 m_freem(m); 686 } else { 687 /* 688 * If ip_dst matched any of my address on !IFF_UP interface, 689 * and there's no IFF_UP interface that matches ip_dst, 690 * send icmp unreach. Forwarding it will result in in-kernel 691 * forwarding loop till TTL goes to 0. 692 */ 693 if (downmatch) { 694 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 695 ipstat.ips_cantforward++; 696 return; 697 } 698#ifdef IPSEC 699 if (ipsec4_in_reject(m, NULL)) { 700 ipsecstat.in_polvio++; 701 goto bad; 702 } 703#endif 704 705 ip_forward(m, 0); 706 } 707 return; 708 709ours: 710 /* 711 * If offset or IP_MF are set, must reassemble. 712 * Otherwise, nothing need be done. 713 * (We could look in the reassembly queue to see 714 * if the packet was previously fragmented, 715 * but it's not worth the time; just let them time out.) 716 */ 717 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 718 if (M_READONLY(m)) { 719 if ((m = m_pullup(m, hlen)) == NULL) { 720 ipstat.ips_toosmall++; 721 goto bad; 722 } 723 ip = mtod(m, struct ip *); 724 } 725 726 /* 727 * Look for queue of fragments 728 * of this datagram. 729 */ 730 IPQ_LOCK(); 731 LIST_FOREACH(fp, &ipq, ipq_q) 732 if (ip->ip_id == fp->ipq_id && 733 in_hosteq(ip->ip_src, fp->ipq_src) && 734 in_hosteq(ip->ip_dst, fp->ipq_dst) && 735 ip->ip_p == fp->ipq_p) 736 goto found; 737 fp = 0; 738found: 739 740 /* 741 * Adjust ip_len to not reflect header, 742 * set ipqe_mff if more fragments are expected, 743 * convert offset of this to bytes. 744 */ 745 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 746 mff = (ip->ip_off & htons(IP_MF)) != 0; 747 if (mff) { 748 /* 749 * Make sure that fragments have a data length 750 * that's a non-zero multiple of 8 bytes. 751 */ 752 if (ntohs(ip->ip_len) == 0 || 753 (ntohs(ip->ip_len) & 0x7) != 0) { 754 ipstat.ips_badfrags++; 755 IPQ_UNLOCK(); 756 goto bad; 757 } 758 } 759 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 760 761 /* 762 * If datagram marked as having more fragments 763 * or if this is not the first fragment, 764 * attempt reassembly; if it succeeds, proceed. 765 */ 766 if (mff || ip->ip_off != htons(0)) { 767 ipstat.ips_fragments++; 768 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 769 if (ipqe == NULL) { 770 ipstat.ips_rcvmemdrop++; 771 IPQ_UNLOCK(); 772 goto bad; 773 } 774 ipqe->ipqe_mff = mff; 775 ipqe->ipqe_m = m; 776 ipqe->ipqe_ip = ip; 777 m = ip_reass(ipqe, fp); 778 if (m == 0) { 779 IPQ_UNLOCK(); 780 return; 781 } 782 ipstat.ips_reassembled++; 783 ip = mtod(m, struct ip *); 784 hlen = ip->ip_hl << 2; 785 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 786 } else 787 if (fp) 788 ip_freef(fp); 789 IPQ_UNLOCK(); 790 } 791 792#ifdef IPSEC 793 /* 794 * enforce IPsec policy checking if we are seeing last header. 795 * note that we do not visit this with protocols with pcb layer 796 * code - like udp/tcp/raw ip. 797 */ 798 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 799 ipsec4_in_reject(m, NULL)) { 800 ipsecstat.in_polvio++; 801 goto bad; 802 } 803#endif 804 805 /* 806 * Switch out to protocol's input routine. 807 */ 808#if IFA_STATS 809 if (ia && ip) 810 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 811#endif 812 ipstat.ips_delivered++; 813 { 814 int off = hlen, nh = ip->ip_p; 815 816 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 817 return; 818 } 819bad: 820 m_freem(m); 821 return; 822 823badcsum: 824 ipstat.ips_badsum++; 825 m_freem(m); 826} 827 828/* 829 * Take incoming datagram fragment and try to 830 * reassemble it into whole datagram. If a chain for 831 * reassembly of this datagram already exists, then it 832 * is given as fp; otherwise have to make a chain. 833 */ 834struct mbuf * 835ip_reass(ipqe, fp) 836 struct ipqent *ipqe; 837 struct ipq *fp; 838{ 839 struct mbuf *m = ipqe->ipqe_m; 840 struct ipqent *nq, *p, *q; 841 struct ip *ip; 842 struct mbuf *t; 843 int hlen = ipqe->ipqe_ip->ip_hl << 2; 844 int i, next; 845 846 IPQ_LOCK_CHECK(); 847 848 /* 849 * Presence of header sizes in mbufs 850 * would confuse code below. 851 */ 852 m->m_data += hlen; 853 m->m_len -= hlen; 854 855 /* 856 * If first fragment to arrive, create a reassembly queue. 857 */ 858 if (fp == 0) { 859 /* 860 * Enforce upper bound on number of fragmented packets 861 * for which we attempt reassembly; 862 * If maxfrag is 0, never accept fragments. 863 * If maxfrag is -1, accept all fragments without limitation. 864 */ 865 if (ip_maxfragpackets < 0) 866 ; 867 else if (ip_nfragpackets >= ip_maxfragpackets) 868 goto dropfrag; 869 ip_nfragpackets++; 870 MALLOC(fp, struct ipq *, sizeof (struct ipq), 871 M_FTABLE, M_NOWAIT); 872 if (fp == NULL) 873 goto dropfrag; 874 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 875 fp->ipq_ttl = IPFRAGTTL; 876 fp->ipq_p = ipqe->ipqe_ip->ip_p; 877 fp->ipq_id = ipqe->ipqe_ip->ip_id; 878 TAILQ_INIT(&fp->ipq_fragq); 879 fp->ipq_src = ipqe->ipqe_ip->ip_src; 880 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 881 p = NULL; 882 goto insert; 883 } 884 885 /* 886 * Find a segment which begins after this one does. 887 */ 888 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 889 p = q, q = TAILQ_NEXT(q, ipqe_q)) 890 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 891 break; 892 893 /* 894 * If there is a preceding segment, it may provide some of 895 * our data already. If so, drop the data from the incoming 896 * segment. If it provides all of our data, drop us. 897 */ 898 if (p != NULL) { 899 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 900 ntohs(ipqe->ipqe_ip->ip_off); 901 if (i > 0) { 902 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 903 goto dropfrag; 904 m_adj(ipqe->ipqe_m, i); 905 ipqe->ipqe_ip->ip_off = 906 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 907 ipqe->ipqe_ip->ip_len = 908 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 909 } 910 } 911 912 /* 913 * While we overlap succeeding segments trim them or, 914 * if they are completely covered, dequeue them. 915 */ 916 for (; q != NULL && 917 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 918 ntohs(q->ipqe_ip->ip_off); q = nq) { 919 i = (ntohs(ipqe->ipqe_ip->ip_off) + 920 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 921 if (i < ntohs(q->ipqe_ip->ip_len)) { 922 q->ipqe_ip->ip_len = 923 htons(ntohs(q->ipqe_ip->ip_len) - i); 924 q->ipqe_ip->ip_off = 925 htons(ntohs(q->ipqe_ip->ip_off) + i); 926 m_adj(q->ipqe_m, i); 927 break; 928 } 929 nq = TAILQ_NEXT(q, ipqe_q); 930 m_freem(q->ipqe_m); 931 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 932 pool_put(&ipqent_pool, q); 933 } 934 935insert: 936 /* 937 * Stick new segment in its place; 938 * check for complete reassembly. 939 */ 940 if (p == NULL) { 941 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 942 } else { 943 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 944 } 945 next = 0; 946 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 947 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 948 if (ntohs(q->ipqe_ip->ip_off) != next) 949 return (0); 950 next += ntohs(q->ipqe_ip->ip_len); 951 } 952 if (p->ipqe_mff) 953 return (0); 954 955 /* 956 * Reassembly is complete. Check for a bogus message size and 957 * concatenate fragments. 958 */ 959 q = TAILQ_FIRST(&fp->ipq_fragq); 960 ip = q->ipqe_ip; 961 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 962 ipstat.ips_toolong++; 963 ip_freef(fp); 964 return (0); 965 } 966 m = q->ipqe_m; 967 t = m->m_next; 968 m->m_next = 0; 969 m_cat(m, t); 970 nq = TAILQ_NEXT(q, ipqe_q); 971 pool_put(&ipqent_pool, q); 972 for (q = nq; q != NULL; q = nq) { 973 t = q->ipqe_m; 974 nq = TAILQ_NEXT(q, ipqe_q); 975 pool_put(&ipqent_pool, q); 976 m_cat(m, t); 977 } 978 979 /* 980 * Create header for new ip packet by 981 * modifying header of first packet; 982 * dequeue and discard fragment reassembly header. 983 * Make header visible. 984 */ 985 ip->ip_len = htons(next); 986 ip->ip_src = fp->ipq_src; 987 ip->ip_dst = fp->ipq_dst; 988 LIST_REMOVE(fp, ipq_q); 989 FREE(fp, M_FTABLE); 990 ip_nfragpackets--; 991 m->m_len += (ip->ip_hl << 2); 992 m->m_data -= (ip->ip_hl << 2); 993 /* some debugging cruft by sklower, below, will go away soon */ 994 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 995 int plen = 0; 996 for (t = m; t; t = t->m_next) 997 plen += t->m_len; 998 m->m_pkthdr.len = plen; 999 } 1000 return (m); 1001 1002dropfrag: 1003 ipstat.ips_fragdropped++; 1004 m_freem(m); 1005 pool_put(&ipqent_pool, ipqe); 1006 return (0); 1007} 1008 1009/* 1010 * Free a fragment reassembly header and all 1011 * associated datagrams. 1012 */ 1013void 1014ip_freef(fp) 1015 struct ipq *fp; 1016{ 1017 struct ipqent *q, *p; 1018 1019 IPQ_LOCK_CHECK(); 1020 1021 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1022 p = TAILQ_NEXT(q, ipqe_q); 1023 m_freem(q->ipqe_m); 1024 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1025 pool_put(&ipqent_pool, q); 1026 } 1027 LIST_REMOVE(fp, ipq_q); 1028 FREE(fp, M_FTABLE); 1029 ip_nfragpackets--; 1030} 1031 1032/* 1033 * IP timer processing; 1034 * if a timer expires on a reassembly 1035 * queue, discard it. 1036 */ 1037void 1038ip_slowtimo() 1039{ 1040 struct ipq *fp, *nfp; 1041 int s = splsoftnet(); 1042 1043 IPQ_LOCK(); 1044 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) { 1045 nfp = LIST_NEXT(fp, ipq_q); 1046 if (--fp->ipq_ttl == 0) { 1047 ipstat.ips_fragtimeout++; 1048 ip_freef(fp); 1049 } 1050 } 1051 /* 1052 * If we are over the maximum number of fragments 1053 * (due to the limit being lowered), drain off 1054 * enough to get down to the new limit. 1055 */ 1056 if (ip_maxfragpackets < 0) 1057 ; 1058 else { 1059 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq)) 1060 ip_freef(LIST_FIRST(&ipq)); 1061 } 1062 IPQ_UNLOCK(); 1063#ifdef GATEWAY 1064 ipflow_slowtimo(); 1065#endif 1066 splx(s); 1067} 1068 1069/* 1070 * Drain off all datagram fragments. 1071 */ 1072void 1073ip_drain() 1074{ 1075 1076 /* 1077 * We may be called from a device's interrupt context. If 1078 * the ipq is already busy, just bail out now. 1079 */ 1080 if (ipq_lock_try() == 0) 1081 return; 1082 1083 while (LIST_FIRST(&ipq) != NULL) { 1084 ipstat.ips_fragdropped++; 1085 ip_freef(LIST_FIRST(&ipq)); 1086 } 1087 1088 IPQ_UNLOCK(); 1089} 1090 1091/* 1092 * Do option processing on a datagram, 1093 * possibly discarding it if bad options are encountered, 1094 * or forwarding it if source-routed. 1095 * Returns 1 if packet has been forwarded/freed, 1096 * 0 if the packet should be processed further. 1097 */ 1098int 1099ip_dooptions(m) 1100 struct mbuf *m; 1101{ 1102 struct ip *ip = mtod(m, struct ip *); 1103 u_char *cp, *cp0; 1104 struct ip_timestamp *ipt; 1105 struct in_ifaddr *ia; 1106 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1107 struct in_addr dst; 1108 n_time ntime; 1109 1110 dst = ip->ip_dst; 1111 cp = (u_char *)(ip + 1); 1112 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1113 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1114 opt = cp[IPOPT_OPTVAL]; 1115 if (opt == IPOPT_EOL) 1116 break; 1117 if (opt == IPOPT_NOP) 1118 optlen = 1; 1119 else { 1120 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1121 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1122 goto bad; 1123 } 1124 optlen = cp[IPOPT_OLEN]; 1125 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1126 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1127 goto bad; 1128 } 1129 } 1130 switch (opt) { 1131 1132 default: 1133 break; 1134 1135 /* 1136 * Source routing with record. 1137 * Find interface with current destination address. 1138 * If none on this machine then drop if strictly routed, 1139 * or do nothing if loosely routed. 1140 * Record interface address and bring up next address 1141 * component. If strictly routed make sure next 1142 * address is on directly accessible net. 1143 */ 1144 case IPOPT_LSRR: 1145 case IPOPT_SSRR: 1146 if (ip_allowsrcrt == 0) { 1147 type = ICMP_UNREACH; 1148 code = ICMP_UNREACH_NET_PROHIB; 1149 goto bad; 1150 } 1151 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1152 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1153 goto bad; 1154 } 1155 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1156 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1157 goto bad; 1158 } 1159 ipaddr.sin_addr = ip->ip_dst; 1160 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1161 if (ia == 0) { 1162 if (opt == IPOPT_SSRR) { 1163 type = ICMP_UNREACH; 1164 code = ICMP_UNREACH_SRCFAIL; 1165 goto bad; 1166 } 1167 /* 1168 * Loose routing, and not at next destination 1169 * yet; nothing to do except forward. 1170 */ 1171 break; 1172 } 1173 off--; /* 0 origin */ 1174 if ((off + sizeof(struct in_addr)) > optlen) { 1175 /* 1176 * End of source route. Should be for us. 1177 */ 1178 save_rte(cp, ip->ip_src); 1179 break; 1180 } 1181 /* 1182 * locate outgoing interface 1183 */ 1184 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 1185 sizeof(ipaddr.sin_addr)); 1186 if (opt == IPOPT_SSRR) 1187 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1188 else 1189 ia = ip_rtaddr(ipaddr.sin_addr); 1190 if (ia == 0) { 1191 type = ICMP_UNREACH; 1192 code = ICMP_UNREACH_SRCFAIL; 1193 goto bad; 1194 } 1195 ip->ip_dst = ipaddr.sin_addr; 1196 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1197 (caddr_t)(cp + off), sizeof(struct in_addr)); 1198 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1199 /* 1200 * Let ip_intr's mcast routing check handle mcast pkts 1201 */ 1202 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1203 break; 1204 1205 case IPOPT_RR: 1206 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1207 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1208 goto bad; 1209 } 1210 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1211 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1212 goto bad; 1213 } 1214 /* 1215 * If no space remains, ignore. 1216 */ 1217 off--; /* 0 origin */ 1218 if ((off + sizeof(struct in_addr)) > optlen) 1219 break; 1220 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 1221 sizeof(ipaddr.sin_addr)); 1222 /* 1223 * locate outgoing interface; if we're the destination, 1224 * use the incoming interface (should be same). 1225 */ 1226 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1227 == NULL && 1228 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1229 type = ICMP_UNREACH; 1230 code = ICMP_UNREACH_HOST; 1231 goto bad; 1232 } 1233 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1234 (caddr_t)(cp + off), sizeof(struct in_addr)); 1235 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1236 break; 1237 1238 case IPOPT_TS: 1239 code = cp - (u_char *)ip; 1240 ipt = (struct ip_timestamp *)cp; 1241 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1242 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1243 goto bad; 1244 } 1245 if (ipt->ipt_ptr < 5) { 1246 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1247 goto bad; 1248 } 1249 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1250 if (++ipt->ipt_oflw == 0) { 1251 code = (u_char *)&ipt->ipt_ptr - 1252 (u_char *)ip; 1253 goto bad; 1254 } 1255 break; 1256 } 1257 cp0 = (cp + ipt->ipt_ptr - 1); 1258 switch (ipt->ipt_flg) { 1259 1260 case IPOPT_TS_TSONLY: 1261 break; 1262 1263 case IPOPT_TS_TSANDADDR: 1264 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1265 sizeof(struct in_addr) > ipt->ipt_len) { 1266 code = (u_char *)&ipt->ipt_ptr - 1267 (u_char *)ip; 1268 goto bad; 1269 } 1270 ipaddr.sin_addr = dst; 1271 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1272 m->m_pkthdr.rcvif)); 1273 if (ia == 0) 1274 continue; 1275 bcopy(&ia->ia_addr.sin_addr, 1276 cp0, sizeof(struct in_addr)); 1277 ipt->ipt_ptr += sizeof(struct in_addr); 1278 break; 1279 1280 case IPOPT_TS_PRESPEC: 1281 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1282 sizeof(struct in_addr) > ipt->ipt_len) { 1283 code = (u_char *)&ipt->ipt_ptr - 1284 (u_char *)ip; 1285 goto bad; 1286 } 1287 bcopy(cp0, &ipaddr.sin_addr, 1288 sizeof(struct in_addr)); 1289 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1290 == NULL) 1291 continue; 1292 ipt->ipt_ptr += sizeof(struct in_addr); 1293 break; 1294 1295 default: 1296 /* XXX can't take &ipt->ipt_flg */ 1297 code = (u_char *)&ipt->ipt_ptr - 1298 (u_char *)ip + 1; 1299 goto bad; 1300 } 1301 ntime = iptime(); 1302 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1303 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1, 1304 sizeof(n_time)); 1305 ipt->ipt_ptr += sizeof(n_time); 1306 } 1307 } 1308 if (forward) { 1309 if (ip_forwsrcrt == 0) { 1310 type = ICMP_UNREACH; 1311 code = ICMP_UNREACH_SRCFAIL; 1312 goto bad; 1313 } 1314 ip_forward(m, 1); 1315 return (1); 1316 } 1317 return (0); 1318bad: 1319 icmp_error(m, type, code, 0, 0); 1320 ipstat.ips_badoptions++; 1321 return (1); 1322} 1323 1324/* 1325 * Given address of next destination (final or next hop), 1326 * return internet address info of interface to be used to get there. 1327 */ 1328struct in_ifaddr * 1329ip_rtaddr(dst) 1330 struct in_addr dst; 1331{ 1332 struct sockaddr_in *sin; 1333 1334 sin = satosin(&ipforward_rt.ro_dst); 1335 1336 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 1337 if (ipforward_rt.ro_rt) { 1338 RTFREE(ipforward_rt.ro_rt); 1339 ipforward_rt.ro_rt = 0; 1340 } 1341 sin->sin_family = AF_INET; 1342 sin->sin_len = sizeof(*sin); 1343 sin->sin_addr = dst; 1344 1345 rtalloc(&ipforward_rt); 1346 } 1347 if (ipforward_rt.ro_rt == 0) 1348 return ((struct in_ifaddr *)0); 1349 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 1350} 1351 1352/* 1353 * Save incoming source route for use in replies, 1354 * to be picked up later by ip_srcroute if the receiver is interested. 1355 */ 1356void 1357save_rte(option, dst) 1358 u_char *option; 1359 struct in_addr dst; 1360{ 1361 unsigned olen; 1362 1363 olen = option[IPOPT_OLEN]; 1364#ifdef DIAGNOSTIC 1365 if (ipprintfs) 1366 printf("save_rte: olen %d\n", olen); 1367#endif /* 0 */ 1368 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1369 return; 1370 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1371 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1372 ip_srcrt.dst = dst; 1373} 1374 1375/* 1376 * Retrieve incoming source route for use in replies, 1377 * in the same form used by setsockopt. 1378 * The first hop is placed before the options, will be removed later. 1379 */ 1380struct mbuf * 1381ip_srcroute() 1382{ 1383 struct in_addr *p, *q; 1384 struct mbuf *m; 1385 1386 if (ip_nhops == 0) 1387 return ((struct mbuf *)0); 1388 m = m_get(M_DONTWAIT, MT_SOOPTS); 1389 if (m == 0) 1390 return ((struct mbuf *)0); 1391 1392#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1393 1394 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1395 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1396 OPTSIZ; 1397#ifdef DIAGNOSTIC 1398 if (ipprintfs) 1399 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1400#endif 1401 1402 /* 1403 * First save first hop for return route 1404 */ 1405 p = &ip_srcrt.route[ip_nhops - 1]; 1406 *(mtod(m, struct in_addr *)) = *p--; 1407#ifdef DIAGNOSTIC 1408 if (ipprintfs) 1409 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1410#endif 1411 1412 /* 1413 * Copy option fields and padding (nop) to mbuf. 1414 */ 1415 ip_srcrt.nop = IPOPT_NOP; 1416 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1417 bcopy((caddr_t)&ip_srcrt.nop, 1418 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1419 q = (struct in_addr *)(mtod(m, caddr_t) + 1420 sizeof(struct in_addr) + OPTSIZ); 1421#undef OPTSIZ 1422 /* 1423 * Record return path as an IP source route, 1424 * reversing the path (pointers are now aligned). 1425 */ 1426 while (p >= ip_srcrt.route) { 1427#ifdef DIAGNOSTIC 1428 if (ipprintfs) 1429 printf(" %x", ntohl(q->s_addr)); 1430#endif 1431 *q++ = *p--; 1432 } 1433 /* 1434 * Last hop goes to final destination. 1435 */ 1436 *q = ip_srcrt.dst; 1437#ifdef DIAGNOSTIC 1438 if (ipprintfs) 1439 printf(" %x\n", ntohl(q->s_addr)); 1440#endif 1441 return (m); 1442} 1443 1444/* 1445 * Strip out IP options, at higher 1446 * level protocol in the kernel. 1447 * Second argument is buffer to which options 1448 * will be moved, and return value is their length. 1449 * XXX should be deleted; last arg currently ignored. 1450 */ 1451void 1452ip_stripoptions(m, mopt) 1453 struct mbuf *m; 1454 struct mbuf *mopt; 1455{ 1456 int i; 1457 struct ip *ip = mtod(m, struct ip *); 1458 caddr_t opts; 1459 int olen; 1460 1461 olen = (ip->ip_hl << 2) - sizeof (struct ip); 1462 opts = (caddr_t)(ip + 1); 1463 i = m->m_len - (sizeof (struct ip) + olen); 1464 bcopy(opts + olen, opts, (unsigned)i); 1465 m->m_len -= olen; 1466 if (m->m_flags & M_PKTHDR) 1467 m->m_pkthdr.len -= olen; 1468 ip->ip_len = htons(ntohs(ip->ip_len) - olen); 1469 ip->ip_hl = sizeof (struct ip) >> 2; 1470} 1471 1472const int inetctlerrmap[PRC_NCMDS] = { 1473 0, 0, 0, 0, 1474 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1475 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1476 EMSGSIZE, EHOSTUNREACH, 0, 0, 1477 0, 0, 0, 0, 1478 ENOPROTOOPT 1479}; 1480 1481/* 1482 * Forward a packet. If some error occurs return the sender 1483 * an icmp packet. Note we can't always generate a meaningful 1484 * icmp message because icmp doesn't have a large enough repertoire 1485 * of codes and types. 1486 * 1487 * If not forwarding, just drop the packet. This could be confusing 1488 * if ipforwarding was zero but some routing protocol was advancing 1489 * us as a gateway to somewhere. However, we must let the routing 1490 * protocol deal with that. 1491 * 1492 * The srcrt parameter indicates whether the packet is being forwarded 1493 * via a source route. 1494 */ 1495void 1496ip_forward(m, srcrt) 1497 struct mbuf *m; 1498 int srcrt; 1499{ 1500 struct ip *ip = mtod(m, struct ip *); 1501 struct sockaddr_in *sin; 1502 struct rtentry *rt; 1503 int error, type = 0, code = 0; 1504 struct mbuf *mcopy; 1505 n_long dest; 1506 struct ifnet *destifp; 1507#ifdef IPSEC 1508 struct ifnet dummyifp; 1509#endif 1510 1511 /* 1512 * Clear any in-bound checksum flags for this packet. 1513 */ 1514 m->m_pkthdr.csum_flags = 0; 1515 1516 dest = 0; 1517#ifdef DIAGNOSTIC 1518 if (ipprintfs) 1519 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1520 ntohl(ip->ip_src.s_addr), 1521 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1522#endif 1523 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1524 ipstat.ips_cantforward++; 1525 m_freem(m); 1526 return; 1527 } 1528 if (ip->ip_ttl <= IPTTLDEC) { 1529 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1530 return; 1531 } 1532 ip->ip_ttl -= IPTTLDEC; 1533 1534 sin = satosin(&ipforward_rt.ro_dst); 1535 if ((rt = ipforward_rt.ro_rt) == 0 || 1536 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1537 if (ipforward_rt.ro_rt) { 1538 RTFREE(ipforward_rt.ro_rt); 1539 ipforward_rt.ro_rt = 0; 1540 } 1541 sin->sin_family = AF_INET; 1542 sin->sin_len = sizeof(struct sockaddr_in); 1543 sin->sin_addr = ip->ip_dst; 1544 1545 rtalloc(&ipforward_rt); 1546 if (ipforward_rt.ro_rt == 0) { 1547 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1548 return; 1549 } 1550 rt = ipforward_rt.ro_rt; 1551 } 1552 1553 /* 1554 * Save at most 68 bytes of the packet in case 1555 * we need to generate an ICMP message to the src. 1556 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1557 */ 1558 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1559 if (mcopy) 1560 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1561 1562 /* 1563 * If forwarding packet using same interface that it came in on, 1564 * perhaps should send a redirect to sender to shortcut a hop. 1565 * Only send redirect if source is sending directly to us, 1566 * and if packet was not source routed (or has any options). 1567 * Also, don't send redirect if forwarding using a default route 1568 * or a route modified by a redirect. 1569 */ 1570 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1571 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1572 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1573 ipsendredirects && !srcrt) { 1574 if (rt->rt_ifa && 1575 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1576 ifatoia(rt->rt_ifa)->ia_subnet) { 1577 if (rt->rt_flags & RTF_GATEWAY) 1578 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1579 else 1580 dest = ip->ip_dst.s_addr; 1581 /* 1582 * Router requirements says to only send host 1583 * redirects. 1584 */ 1585 type = ICMP_REDIRECT; 1586 code = ICMP_REDIRECT_HOST; 1587#ifdef DIAGNOSTIC 1588 if (ipprintfs) 1589 printf("redirect (%d) to %x\n", code, 1590 (u_int32_t)dest); 1591#endif 1592 } 1593 } 1594 1595#ifdef IPSEC 1596 /* Don't lookup socket in forwarding case */ 1597 (void)ipsec_setsocket(m, NULL); 1598#endif 1599 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1600 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1601 if (error) 1602 ipstat.ips_cantforward++; 1603 else { 1604 ipstat.ips_forward++; 1605 if (type) 1606 ipstat.ips_redirectsent++; 1607 else { 1608 if (mcopy) { 1609#ifdef GATEWAY 1610 if (mcopy->m_flags & M_CANFASTFWD) 1611 ipflow_create(&ipforward_rt, mcopy); 1612#endif 1613 m_freem(mcopy); 1614 } 1615 return; 1616 } 1617 } 1618 if (mcopy == NULL) 1619 return; 1620 destifp = NULL; 1621 1622 switch (error) { 1623 1624 case 0: /* forwarded, but need redirect */ 1625 /* type, code set above */ 1626 break; 1627 1628 case ENETUNREACH: /* shouldn't happen, checked above */ 1629 case EHOSTUNREACH: 1630 case ENETDOWN: 1631 case EHOSTDOWN: 1632 default: 1633 type = ICMP_UNREACH; 1634 code = ICMP_UNREACH_HOST; 1635 break; 1636 1637 case EMSGSIZE: 1638 type = ICMP_UNREACH; 1639 code = ICMP_UNREACH_NEEDFRAG; 1640#ifndef IPSEC 1641 if (ipforward_rt.ro_rt) 1642 destifp = ipforward_rt.ro_rt->rt_ifp; 1643#else 1644 /* 1645 * If the packet is routed over IPsec tunnel, tell the 1646 * originator the tunnel MTU. 1647 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1648 * XXX quickhack!!! 1649 */ 1650 if (ipforward_rt.ro_rt) { 1651 struct secpolicy *sp; 1652 int ipsecerror; 1653 size_t ipsechdr; 1654 struct route *ro; 1655 1656 sp = ipsec4_getpolicybyaddr(mcopy, 1657 IPSEC_DIR_OUTBOUND, 1658 IP_FORWARDING, 1659 &ipsecerror); 1660 1661 if (sp == NULL) 1662 destifp = ipforward_rt.ro_rt->rt_ifp; 1663 else { 1664 /* count IPsec header size */ 1665 ipsechdr = ipsec4_hdrsiz(mcopy, 1666 IPSEC_DIR_OUTBOUND, 1667 NULL); 1668 1669 /* 1670 * find the correct route for outer IPv4 1671 * header, compute tunnel MTU. 1672 * 1673 * XXX BUG ALERT 1674 * The "dummyifp" code relies upon the fact 1675 * that icmp_error() touches only ifp->if_mtu. 1676 */ 1677 /*XXX*/ 1678 destifp = NULL; 1679 if (sp->req != NULL 1680 && sp->req->sav != NULL 1681 && sp->req->sav->sah != NULL) { 1682 ro = &sp->req->sav->sah->sa_route; 1683 if (ro->ro_rt && ro->ro_rt->rt_ifp) { 1684 dummyifp.if_mtu = 1685 ro->ro_rt->rt_rmx.rmx_mtu ? 1686 ro->ro_rt->rt_rmx.rmx_mtu : 1687 ro->ro_rt->rt_ifp->if_mtu; 1688 dummyifp.if_mtu -= ipsechdr; 1689 destifp = &dummyifp; 1690 } 1691 } 1692 1693 key_freesp(sp); 1694 } 1695 } 1696#endif /*IPSEC*/ 1697 ipstat.ips_cantfrag++; 1698 break; 1699 1700 case ENOBUFS: 1701#if 1 1702 /* 1703 * a router should not generate ICMP_SOURCEQUENCH as 1704 * required in RFC1812 Requirements for IP Version 4 Routers. 1705 * source quench could be a big problem under DoS attacks, 1706 * or if the underlying interface is rate-limited. 1707 */ 1708 if (mcopy) 1709 m_freem(mcopy); 1710 return; 1711#else 1712 type = ICMP_SOURCEQUENCH; 1713 code = 0; 1714 break; 1715#endif 1716 } 1717 icmp_error(mcopy, type, code, dest, destifp); 1718} 1719 1720void 1721ip_savecontrol(inp, mp, ip, m) 1722 struct inpcb *inp; 1723 struct mbuf **mp; 1724 struct ip *ip; 1725 struct mbuf *m; 1726{ 1727 1728 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1729 struct timeval tv; 1730 1731 microtime(&tv); 1732 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1733 SCM_TIMESTAMP, SOL_SOCKET); 1734 if (*mp) 1735 mp = &(*mp)->m_next; 1736 } 1737 if (inp->inp_flags & INP_RECVDSTADDR) { 1738 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1739 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1740 if (*mp) 1741 mp = &(*mp)->m_next; 1742 } 1743#ifdef notyet 1744 /* 1745 * XXX 1746 * Moving these out of udp_input() made them even more broken 1747 * than they already were. 1748 * - fenner@parc.xerox.com 1749 */ 1750 /* options were tossed already */ 1751 if (inp->inp_flags & INP_RECVOPTS) { 1752 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1753 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1754 if (*mp) 1755 mp = &(*mp)->m_next; 1756 } 1757 /* ip_srcroute doesn't do what we want here, need to fix */ 1758 if (inp->inp_flags & INP_RECVRETOPTS) { 1759 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1760 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1761 if (*mp) 1762 mp = &(*mp)->m_next; 1763 } 1764#endif 1765 if (inp->inp_flags & INP_RECVIF) { 1766 struct sockaddr_dl sdl; 1767 1768 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1769 sdl.sdl_family = AF_LINK; 1770 sdl.sdl_index = m->m_pkthdr.rcvif ? 1771 m->m_pkthdr.rcvif->if_index : 0; 1772 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1773 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1774 IP_RECVIF, IPPROTO_IP); 1775 if (*mp) 1776 mp = &(*mp)->m_next; 1777 } 1778} 1779 1780int 1781ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1782 int *name; 1783 u_int namelen; 1784 void *oldp; 1785 size_t *oldlenp; 1786 void *newp; 1787 size_t newlen; 1788{ 1789 extern int subnetsarelocal, hostzeroisbroadcast; 1790 1791 int error, old; 1792 1793 /* All sysctl names at this level are terminal. */ 1794 if (namelen != 1) 1795 return (ENOTDIR); 1796 1797 switch (name[0]) { 1798 case IPCTL_FORWARDING: 1799 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1800 case IPCTL_SENDREDIRECTS: 1801 return (sysctl_int(oldp, oldlenp, newp, newlen, 1802 &ipsendredirects)); 1803 case IPCTL_DEFTTL: 1804 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1805#ifdef notyet 1806 case IPCTL_DEFMTU: 1807 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1808#endif 1809 case IPCTL_FORWSRCRT: 1810 /* Don't allow this to change in a secure environment. */ 1811 if (securelevel > 0) 1812 return (sysctl_rdint(oldp, oldlenp, newp, 1813 ip_forwsrcrt)); 1814 else 1815 return (sysctl_int(oldp, oldlenp, newp, newlen, 1816 &ip_forwsrcrt)); 1817 case IPCTL_DIRECTEDBCAST: 1818 return (sysctl_int(oldp, oldlenp, newp, newlen, 1819 &ip_directedbcast)); 1820 case IPCTL_ALLOWSRCRT: 1821 return (sysctl_int(oldp, oldlenp, newp, newlen, 1822 &ip_allowsrcrt)); 1823 case IPCTL_SUBNETSARELOCAL: 1824 return (sysctl_int(oldp, oldlenp, newp, newlen, 1825 &subnetsarelocal)); 1826 case IPCTL_MTUDISC: 1827 error = sysctl_int(oldp, oldlenp, newp, newlen, 1828 &ip_mtudisc); 1829 if (ip_mtudisc == 0) 1830 rt_timer_queue_remove_all(ip_mtudisc_timeout_q, TRUE); 1831 return error; 1832 case IPCTL_ANONPORTMIN: 1833 old = anonportmin; 1834 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1835 if (anonportmin >= anonportmax || anonportmin < 0 1836 || anonportmin > 65535 1837#ifndef IPNOPRIVPORTS 1838 || anonportmin < IPPORT_RESERVED 1839#endif 1840 ) { 1841 anonportmin = old; 1842 return (EINVAL); 1843 } 1844 return (error); 1845 case IPCTL_ANONPORTMAX: 1846 old = anonportmax; 1847 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1848 if (anonportmin >= anonportmax || anonportmax < 0 1849 || anonportmax > 65535 1850#ifndef IPNOPRIVPORTS 1851 || anonportmax < IPPORT_RESERVED 1852#endif 1853 ) { 1854 anonportmax = old; 1855 return (EINVAL); 1856 } 1857 return (error); 1858 case IPCTL_MTUDISCTIMEOUT: 1859 old = ip_mtudisc_timeout; 1860 error = sysctl_int(oldp, oldlenp, newp, newlen, 1861 &ip_mtudisc_timeout); 1862 if (ip_mtudisc_timeout < 0) { 1863 ip_mtudisc_timeout = old; 1864 return (EINVAL); 1865 } 1866 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 1867 return (error); 1868#ifdef GATEWAY 1869 case IPCTL_MAXFLOWS: 1870 { 1871 int s; 1872 1873 error = sysctl_int(oldp, oldlenp, newp, newlen, 1874 &ip_maxflows); 1875 s = splsoftnet(); 1876 ipflow_reap(0); 1877 splx(s); 1878 return (error); 1879 } 1880#endif 1881 case IPCTL_HOSTZEROBROADCAST: 1882 return (sysctl_int(oldp, oldlenp, newp, newlen, 1883 &hostzeroisbroadcast)); 1884#if NGIF > 0 1885 case IPCTL_GIF_TTL: 1886 return (sysctl_int(oldp, oldlenp, newp, newlen, 1887 &ip_gif_ttl)); 1888#endif 1889 1890#if NGRE > 0 1891 case IPCTL_GRE_TTL: 1892 return (sysctl_int(oldp, oldlenp, newp, newlen, 1893 &ip_gre_ttl)); 1894#endif 1895 1896#ifndef IPNOPRIVPORTS 1897 case IPCTL_LOWPORTMIN: 1898 old = lowportmin; 1899 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin); 1900 if (lowportmin >= lowportmax 1901 || lowportmin > IPPORT_RESERVEDMAX 1902 || lowportmin < IPPORT_RESERVEDMIN 1903 ) { 1904 lowportmin = old; 1905 return (EINVAL); 1906 } 1907 return (error); 1908 case IPCTL_LOWPORTMAX: 1909 old = lowportmax; 1910 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax); 1911 if (lowportmin >= lowportmax 1912 || lowportmax > IPPORT_RESERVEDMAX 1913 || lowportmax < IPPORT_RESERVEDMIN 1914 ) { 1915 lowportmax = old; 1916 return (EINVAL); 1917 } 1918 return (error); 1919#endif 1920 1921 case IPCTL_MAXFRAGPACKETS: 1922 return (sysctl_int(oldp, oldlenp, newp, newlen, 1923 &ip_maxfragpackets)); 1924 1925 default: 1926 return (EOPNOTSUPP); 1927 } 1928 /* NOTREACHED */ 1929} 1930