ip_input.c revision 1.164
1/* $NetBSD: ip_input.c,v 1.164 2003/02/26 06:31:14 matt 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 1.164 2003/02/26 06:31:14 matt 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#ifdef MBUFTRACE 313struct mowner ip_rx_mowner = { "internet", "rx" }; 314struct mowner ip_tx_mowner = { "internet", "tx" }; 315#endif 316 317/* 318 * IP initialization: fill in IP protocol switch table. 319 * All protocols not implemented in kernel go to raw IP protocol handler. 320 */ 321void 322ip_init() 323{ 324 struct protosw *pr; 325 int i; 326 327 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 328 NULL); 329 330 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 331 if (pr == 0) 332 panic("ip_init"); 333 for (i = 0; i < IPPROTO_MAX; i++) 334 ip_protox[i] = pr - inetsw; 335 for (pr = inetdomain.dom_protosw; 336 pr < inetdomain.dom_protoswNPROTOSW; pr++) 337 if (pr->pr_domain->dom_family == PF_INET && 338 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 339 ip_protox[pr->pr_protocol] = pr - inetsw; 340 LIST_INIT(&ipq); 341 ip_id = time.tv_sec & 0xffff; 342 ipintrq.ifq_maxlen = ipqmaxlen; 343 TAILQ_INIT(&in_ifaddr); 344 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR, 345 M_WAITOK, &in_ifaddrhash); 346 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 347#ifdef GATEWAY 348 ipflow_init(); 349#endif 350 351#ifdef PFIL_HOOKS 352 /* Register our Packet Filter hook. */ 353 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 354 inet_pfil_hook.ph_af = AF_INET; 355 i = pfil_head_register(&inet_pfil_hook); 356 if (i != 0) 357 printf("ip_init: WARNING: unable to register pfil hook, " 358 "error %d\n", i); 359#endif /* PFIL_HOOKS */ 360 361#ifdef INET_CSUM_COUNTERS 362 evcnt_attach_static(&ip_hwcsum_bad); 363 evcnt_attach_static(&ip_hwcsum_ok); 364 evcnt_attach_static(&ip_swcsum); 365#endif /* INET_CSUM_COUNTERS */ 366 367#ifdef MBUFTRACE 368 MOWNER_ATTACH(&ip_tx_mowner); 369 MOWNER_ATTACH(&ip_rx_mowner); 370#endif /* MBUFTRACE */ 371} 372 373struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 374struct route ipforward_rt; 375 376/* 377 * IP software interrupt routine 378 */ 379void 380ipintr() 381{ 382 int s; 383 struct mbuf *m; 384 385 while (1) { 386 s = splnet(); 387 IF_DEQUEUE(&ipintrq, m); 388 splx(s); 389 if (m == 0) 390 return; 391 MCLAIM(m, &ip_rx_mowner); 392 ip_input(m); 393 } 394} 395 396/* 397 * Ip input routine. Checksum and byte swap header. If fragmented 398 * try to reassemble. Process options. Pass to next level. 399 */ 400void 401ip_input(struct mbuf *m) 402{ 403 struct ip *ip = NULL; 404 struct ipq *fp; 405 struct in_ifaddr *ia; 406 struct ifaddr *ifa; 407 struct ipqent *ipqe; 408 int hlen = 0, mff, len; 409 int downmatch; 410 411 MCLAIM(m, &ip_rx_mowner); 412#ifdef DIAGNOSTIC 413 if ((m->m_flags & M_PKTHDR) == 0) 414 panic("ipintr no HDR"); 415#endif 416#ifdef IPSEC 417 /* 418 * should the inner packet be considered authentic? 419 * see comment in ah4_input(). 420 */ 421 if (m) { 422 m->m_flags &= ~M_AUTHIPHDR; 423 m->m_flags &= ~M_AUTHIPDGM; 424 } 425#endif 426 427 /* 428 * If no IP addresses have been set yet but the interfaces 429 * are receiving, can't do anything with incoming packets yet. 430 */ 431 if (TAILQ_FIRST(&in_ifaddr) == 0) 432 goto bad; 433 ipstat.ips_total++; 434 /* 435 * If the IP header is not aligned, slurp it up into a new 436 * mbuf with space for link headers, in the event we forward 437 * it. Otherwise, if it is aligned, make sure the entire 438 * base IP header is in the first mbuf of the chain. 439 */ 440 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) { 441 if ((m = m_copyup(m, sizeof(struct ip), 442 (max_linkhdr + 3) & ~3)) == NULL) { 443 /* XXXJRT new stat, please */ 444 ipstat.ips_toosmall++; 445 return; 446 } 447 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 448 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 449 ipstat.ips_toosmall++; 450 return; 451 } 452 } 453 ip = mtod(m, struct ip *); 454 if (ip->ip_v != IPVERSION) { 455 ipstat.ips_badvers++; 456 goto bad; 457 } 458 hlen = ip->ip_hl << 2; 459 if (hlen < sizeof(struct ip)) { /* minimum header length */ 460 ipstat.ips_badhlen++; 461 goto bad; 462 } 463 if (hlen > m->m_len) { 464 if ((m = m_pullup(m, hlen)) == 0) { 465 ipstat.ips_badhlen++; 466 return; 467 } 468 ip = mtod(m, struct ip *); 469 } 470 471 /* 472 * RFC1122: packets with a multicast source address are 473 * not allowed. 474 */ 475 if (IN_MULTICAST(ip->ip_src.s_addr)) { 476 ipstat.ips_badaddr++; 477 goto bad; 478 } 479 480 /* 127/8 must not appear on wire - RFC1122 */ 481 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 482 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 483 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 484 ipstat.ips_badaddr++; 485 goto bad; 486 } 487 } 488 489 switch (m->m_pkthdr.csum_flags & 490 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 491 M_CSUM_IPv4_BAD)) { 492 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 493 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 494 goto badcsum; 495 496 case M_CSUM_IPv4: 497 /* Checksum was okay. */ 498 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 499 break; 500 501 default: 502 /* Must compute it ourselves. */ 503 INET_CSUM_COUNTER_INCR(&ip_swcsum); 504 if (in_cksum(m, hlen) != 0) 505 goto bad; 506 break; 507 } 508 509 /* Retrieve the packet length. */ 510 len = ntohs(ip->ip_len); 511 512 /* 513 * Check for additional length bogosity 514 */ 515 if (len < hlen) { 516 ipstat.ips_badlen++; 517 goto bad; 518 } 519 520 /* 521 * Check that the amount of data in the buffers 522 * is as at least much as the IP header would have us expect. 523 * Trim mbufs if longer than we expect. 524 * Drop packet if shorter than we expect. 525 */ 526 if (m->m_pkthdr.len < len) { 527 ipstat.ips_tooshort++; 528 goto bad; 529 } 530 if (m->m_pkthdr.len > len) { 531 if (m->m_len == m->m_pkthdr.len) { 532 m->m_len = len; 533 m->m_pkthdr.len = len; 534 } else 535 m_adj(m, len - m->m_pkthdr.len); 536 } 537 538#ifdef IPSEC 539 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 540 m->m_flags &= ~M_CANFASTFWD; 541#else 542 /* 543 * Assume that we can create a fast-forward IP flow entry 544 * based on this packet. 545 */ 546 m->m_flags |= M_CANFASTFWD; 547#endif 548 549#ifdef PFIL_HOOKS 550 /* 551 * Run through list of hooks for input packets. If there are any 552 * filters which require that additional packets in the flow are 553 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 554 * Note that filters must _never_ set this flag, as another filter 555 * in the list may have previously cleared it. 556 */ 557 /* 558 * let ipfilter look at packet on the wire, 559 * not the decapsulated packet. 560 */ 561#ifdef IPSEC 562 if (!ipsec_getnhist(m)) 563#else 564 if (1) 565#endif 566 { 567 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 568 PFIL_IN) != 0) 569 return; 570 if (m == NULL) 571 return; 572 ip = mtod(m, struct ip *); 573 hlen = ip->ip_hl << 2; 574 } 575#endif /* PFIL_HOOKS */ 576 577#ifdef ALTQ 578 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 579 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 580 /* packet dropped by traffic conditioner */ 581 return; 582 } 583#endif 584 585 /* 586 * Process options and, if not destined for us, 587 * ship it on. ip_dooptions returns 1 when an 588 * error was detected (causing an icmp message 589 * to be sent and the original packet to be freed). 590 */ 591 ip_nhops = 0; /* for source routed packets */ 592 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 593 return; 594 595 /* 596 * Check our list of addresses, to see if the packet is for us. 597 * 598 * Traditional 4.4BSD did not consult IFF_UP at all. 599 * The behavior here is to treat addresses on !IFF_UP interface 600 * as not mine. 601 */ 602 downmatch = 0; 603 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 604 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 605 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 606 break; 607 else 608 downmatch++; 609 } 610 } 611 if (ia != NULL) 612 goto ours; 613 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 614 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) { 615 if (ifa->ifa_addr->sa_family != AF_INET) 616 continue; 617 ia = ifatoia(ifa); 618 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 619 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 620 /* 621 * Look for all-0's host part (old broadcast addr), 622 * either for subnet or net. 623 */ 624 ip->ip_dst.s_addr == ia->ia_subnet || 625 ip->ip_dst.s_addr == ia->ia_net) 626 goto ours; 627 /* 628 * An interface with IP address zero accepts 629 * all packets that arrive on that interface. 630 */ 631 if (in_nullhost(ia->ia_addr.sin_addr)) 632 goto ours; 633 } 634 } 635 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 636 struct in_multi *inm; 637#ifdef MROUTING 638 extern struct socket *ip_mrouter; 639 640 if (M_READONLY(m)) { 641 if ((m = m_pullup(m, hlen)) == 0) { 642 ipstat.ips_toosmall++; 643 return; 644 } 645 ip = mtod(m, struct ip *); 646 } 647 648 if (ip_mrouter) { 649 /* 650 * If we are acting as a multicast router, all 651 * incoming multicast packets are passed to the 652 * kernel-level multicast forwarding function. 653 * The packet is returned (relatively) intact; if 654 * ip_mforward() returns a non-zero value, the packet 655 * must be discarded, else it may be accepted below. 656 * 657 * (The IP ident field is put in the same byte order 658 * as expected when ip_mforward() is called from 659 * ip_output().) 660 */ 661 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 662 ipstat.ips_cantforward++; 663 m_freem(m); 664 return; 665 } 666 667 /* 668 * The process-level routing demon needs to receive 669 * all multicast IGMP packets, whether or not this 670 * host belongs to their destination groups. 671 */ 672 if (ip->ip_p == IPPROTO_IGMP) 673 goto ours; 674 ipstat.ips_forward++; 675 } 676#endif 677 /* 678 * See if we belong to the destination multicast group on the 679 * arrival interface. 680 */ 681 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 682 if (inm == NULL) { 683 ipstat.ips_cantforward++; 684 m_freem(m); 685 return; 686 } 687 goto ours; 688 } 689 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 690 in_nullhost(ip->ip_dst)) 691 goto ours; 692 693 /* 694 * Not for us; forward if possible and desirable. 695 */ 696 if (ipforwarding == 0) { 697 ipstat.ips_cantforward++; 698 m_freem(m); 699 } else { 700 /* 701 * If ip_dst matched any of my address on !IFF_UP interface, 702 * and there's no IFF_UP interface that matches ip_dst, 703 * send icmp unreach. Forwarding it will result in in-kernel 704 * forwarding loop till TTL goes to 0. 705 */ 706 if (downmatch) { 707 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 708 ipstat.ips_cantforward++; 709 return; 710 } 711#ifdef IPSEC 712 if (ipsec4_in_reject(m, NULL)) { 713 ipsecstat.in_polvio++; 714 goto bad; 715 } 716#endif 717 718 ip_forward(m, 0); 719 } 720 return; 721 722ours: 723 /* 724 * If offset or IP_MF are set, must reassemble. 725 * Otherwise, nothing need be done. 726 * (We could look in the reassembly queue to see 727 * if the packet was previously fragmented, 728 * but it's not worth the time; just let them time out.) 729 */ 730 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 731 if (M_READONLY(m)) { 732 if ((m = m_pullup(m, hlen)) == NULL) { 733 ipstat.ips_toosmall++; 734 goto bad; 735 } 736 ip = mtod(m, struct ip *); 737 } 738 739 /* 740 * Look for queue of fragments 741 * of this datagram. 742 */ 743 IPQ_LOCK(); 744 LIST_FOREACH(fp, &ipq, ipq_q) 745 if (ip->ip_id == fp->ipq_id && 746 in_hosteq(ip->ip_src, fp->ipq_src) && 747 in_hosteq(ip->ip_dst, fp->ipq_dst) && 748 ip->ip_p == fp->ipq_p) 749 goto found; 750 fp = 0; 751found: 752 753 /* 754 * Adjust ip_len to not reflect header, 755 * set ipqe_mff if more fragments are expected, 756 * convert offset of this to bytes. 757 */ 758 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 759 mff = (ip->ip_off & htons(IP_MF)) != 0; 760 if (mff) { 761 /* 762 * Make sure that fragments have a data length 763 * that's a non-zero multiple of 8 bytes. 764 */ 765 if (ntohs(ip->ip_len) == 0 || 766 (ntohs(ip->ip_len) & 0x7) != 0) { 767 ipstat.ips_badfrags++; 768 IPQ_UNLOCK(); 769 goto bad; 770 } 771 } 772 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 773 774 /* 775 * If datagram marked as having more fragments 776 * or if this is not the first fragment, 777 * attempt reassembly; if it succeeds, proceed. 778 */ 779 if (mff || ip->ip_off != htons(0)) { 780 ipstat.ips_fragments++; 781 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 782 if (ipqe == NULL) { 783 ipstat.ips_rcvmemdrop++; 784 IPQ_UNLOCK(); 785 goto bad; 786 } 787 ipqe->ipqe_mff = mff; 788 ipqe->ipqe_m = m; 789 ipqe->ipqe_ip = ip; 790 m = ip_reass(ipqe, fp); 791 if (m == 0) { 792 IPQ_UNLOCK(); 793 return; 794 } 795 ipstat.ips_reassembled++; 796 ip = mtod(m, struct ip *); 797 hlen = ip->ip_hl << 2; 798 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 799 } else 800 if (fp) 801 ip_freef(fp); 802 IPQ_UNLOCK(); 803 } 804 805#ifdef IPSEC 806 /* 807 * enforce IPsec policy checking if we are seeing last header. 808 * note that we do not visit this with protocols with pcb layer 809 * code - like udp/tcp/raw ip. 810 */ 811 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 812 ipsec4_in_reject(m, NULL)) { 813 ipsecstat.in_polvio++; 814 goto bad; 815 } 816#endif 817 818 /* 819 * Switch out to protocol's input routine. 820 */ 821#if IFA_STATS 822 if (ia && ip) 823 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 824#endif 825 ipstat.ips_delivered++; 826 { 827 int off = hlen, nh = ip->ip_p; 828 829 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 830 return; 831 } 832bad: 833 m_freem(m); 834 return; 835 836badcsum: 837 ipstat.ips_badsum++; 838 m_freem(m); 839} 840 841/* 842 * Take incoming datagram fragment and try to 843 * reassemble it into whole datagram. If a chain for 844 * reassembly of this datagram already exists, then it 845 * is given as fp; otherwise have to make a chain. 846 */ 847struct mbuf * 848ip_reass(ipqe, fp) 849 struct ipqent *ipqe; 850 struct ipq *fp; 851{ 852 struct mbuf *m = ipqe->ipqe_m; 853 struct ipqent *nq, *p, *q; 854 struct ip *ip; 855 struct mbuf *t; 856 int hlen = ipqe->ipqe_ip->ip_hl << 2; 857 int i, next; 858 859 IPQ_LOCK_CHECK(); 860 861 /* 862 * Presence of header sizes in mbufs 863 * would confuse code below. 864 */ 865 m->m_data += hlen; 866 m->m_len -= hlen; 867 868 /* 869 * If first fragment to arrive, create a reassembly queue. 870 */ 871 if (fp == 0) { 872 /* 873 * Enforce upper bound on number of fragmented packets 874 * for which we attempt reassembly; 875 * If maxfrag is 0, never accept fragments. 876 * If maxfrag is -1, accept all fragments without limitation. 877 */ 878 if (ip_maxfragpackets < 0) 879 ; 880 else if (ip_nfragpackets >= ip_maxfragpackets) 881 goto dropfrag; 882 ip_nfragpackets++; 883 MALLOC(fp, struct ipq *, sizeof (struct ipq), 884 M_FTABLE, M_NOWAIT); 885 if (fp == NULL) 886 goto dropfrag; 887 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 888 fp->ipq_ttl = IPFRAGTTL; 889 fp->ipq_p = ipqe->ipqe_ip->ip_p; 890 fp->ipq_id = ipqe->ipqe_ip->ip_id; 891 TAILQ_INIT(&fp->ipq_fragq); 892 fp->ipq_src = ipqe->ipqe_ip->ip_src; 893 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 894 p = NULL; 895 goto insert; 896 } 897 898 /* 899 * Find a segment which begins after this one does. 900 */ 901 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 902 p = q, q = TAILQ_NEXT(q, ipqe_q)) 903 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 904 break; 905 906 /* 907 * If there is a preceding segment, it may provide some of 908 * our data already. If so, drop the data from the incoming 909 * segment. If it provides all of our data, drop us. 910 */ 911 if (p != NULL) { 912 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 913 ntohs(ipqe->ipqe_ip->ip_off); 914 if (i > 0) { 915 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 916 goto dropfrag; 917 m_adj(ipqe->ipqe_m, i); 918 ipqe->ipqe_ip->ip_off = 919 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 920 ipqe->ipqe_ip->ip_len = 921 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 922 } 923 } 924 925 /* 926 * While we overlap succeeding segments trim them or, 927 * if they are completely covered, dequeue them. 928 */ 929 for (; q != NULL && 930 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 931 ntohs(q->ipqe_ip->ip_off); q = nq) { 932 i = (ntohs(ipqe->ipqe_ip->ip_off) + 933 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 934 if (i < ntohs(q->ipqe_ip->ip_len)) { 935 q->ipqe_ip->ip_len = 936 htons(ntohs(q->ipqe_ip->ip_len) - i); 937 q->ipqe_ip->ip_off = 938 htons(ntohs(q->ipqe_ip->ip_off) + i); 939 m_adj(q->ipqe_m, i); 940 break; 941 } 942 nq = TAILQ_NEXT(q, ipqe_q); 943 m_freem(q->ipqe_m); 944 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 945 pool_put(&ipqent_pool, q); 946 } 947 948insert: 949 /* 950 * Stick new segment in its place; 951 * check for complete reassembly. 952 */ 953 if (p == NULL) { 954 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 955 } else { 956 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 957 } 958 next = 0; 959 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 960 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 961 if (ntohs(q->ipqe_ip->ip_off) != next) 962 return (0); 963 next += ntohs(q->ipqe_ip->ip_len); 964 } 965 if (p->ipqe_mff) 966 return (0); 967 968 /* 969 * Reassembly is complete. Check for a bogus message size and 970 * concatenate fragments. 971 */ 972 q = TAILQ_FIRST(&fp->ipq_fragq); 973 ip = q->ipqe_ip; 974 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 975 ipstat.ips_toolong++; 976 ip_freef(fp); 977 return (0); 978 } 979 m = q->ipqe_m; 980 t = m->m_next; 981 m->m_next = 0; 982 m_cat(m, t); 983 nq = TAILQ_NEXT(q, ipqe_q); 984 pool_put(&ipqent_pool, q); 985 for (q = nq; q != NULL; q = nq) { 986 t = q->ipqe_m; 987 nq = TAILQ_NEXT(q, ipqe_q); 988 pool_put(&ipqent_pool, q); 989 m_cat(m, t); 990 } 991 992 /* 993 * Create header for new ip packet by 994 * modifying header of first packet; 995 * dequeue and discard fragment reassembly header. 996 * Make header visible. 997 */ 998 ip->ip_len = htons(next); 999 ip->ip_src = fp->ipq_src; 1000 ip->ip_dst = fp->ipq_dst; 1001 LIST_REMOVE(fp, ipq_q); 1002 FREE(fp, M_FTABLE); 1003 ip_nfragpackets--; 1004 m->m_len += (ip->ip_hl << 2); 1005 m->m_data -= (ip->ip_hl << 2); 1006 /* some debugging cruft by sklower, below, will go away soon */ 1007 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1008 int plen = 0; 1009 for (t = m; t; t = t->m_next) 1010 plen += t->m_len; 1011 m->m_pkthdr.len = plen; 1012 } 1013 return (m); 1014 1015dropfrag: 1016 ipstat.ips_fragdropped++; 1017 m_freem(m); 1018 pool_put(&ipqent_pool, ipqe); 1019 return (0); 1020} 1021 1022/* 1023 * Free a fragment reassembly header and all 1024 * associated datagrams. 1025 */ 1026void 1027ip_freef(fp) 1028 struct ipq *fp; 1029{ 1030 struct ipqent *q, *p; 1031 1032 IPQ_LOCK_CHECK(); 1033 1034 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1035 p = TAILQ_NEXT(q, ipqe_q); 1036 m_freem(q->ipqe_m); 1037 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1038 pool_put(&ipqent_pool, q); 1039 } 1040 LIST_REMOVE(fp, ipq_q); 1041 FREE(fp, M_FTABLE); 1042 ip_nfragpackets--; 1043} 1044 1045/* 1046 * IP timer processing; 1047 * if a timer expires on a reassembly 1048 * queue, discard it. 1049 */ 1050void 1051ip_slowtimo() 1052{ 1053 struct ipq *fp, *nfp; 1054 int s = splsoftnet(); 1055 1056 IPQ_LOCK(); 1057 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) { 1058 nfp = LIST_NEXT(fp, ipq_q); 1059 if (--fp->ipq_ttl == 0) { 1060 ipstat.ips_fragtimeout++; 1061 ip_freef(fp); 1062 } 1063 } 1064 /* 1065 * If we are over the maximum number of fragments 1066 * (due to the limit being lowered), drain off 1067 * enough to get down to the new limit. 1068 */ 1069 if (ip_maxfragpackets < 0) 1070 ; 1071 else { 1072 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq)) 1073 ip_freef(LIST_FIRST(&ipq)); 1074 } 1075 IPQ_UNLOCK(); 1076#ifdef GATEWAY 1077 ipflow_slowtimo(); 1078#endif 1079 splx(s); 1080} 1081 1082/* 1083 * Drain off all datagram fragments. 1084 */ 1085void 1086ip_drain() 1087{ 1088 1089 /* 1090 * We may be called from a device's interrupt context. If 1091 * the ipq is already busy, just bail out now. 1092 */ 1093 if (ipq_lock_try() == 0) 1094 return; 1095 1096 while (LIST_FIRST(&ipq) != NULL) { 1097 ipstat.ips_fragdropped++; 1098 ip_freef(LIST_FIRST(&ipq)); 1099 } 1100 1101 IPQ_UNLOCK(); 1102} 1103 1104/* 1105 * Do option processing on a datagram, 1106 * possibly discarding it if bad options are encountered, 1107 * or forwarding it if source-routed. 1108 * Returns 1 if packet has been forwarded/freed, 1109 * 0 if the packet should be processed further. 1110 */ 1111int 1112ip_dooptions(m) 1113 struct mbuf *m; 1114{ 1115 struct ip *ip = mtod(m, struct ip *); 1116 u_char *cp, *cp0; 1117 struct ip_timestamp *ipt; 1118 struct in_ifaddr *ia; 1119 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1120 struct in_addr dst; 1121 n_time ntime; 1122 1123 dst = ip->ip_dst; 1124 cp = (u_char *)(ip + 1); 1125 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1126 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1127 opt = cp[IPOPT_OPTVAL]; 1128 if (opt == IPOPT_EOL) 1129 break; 1130 if (opt == IPOPT_NOP) 1131 optlen = 1; 1132 else { 1133 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1134 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1135 goto bad; 1136 } 1137 optlen = cp[IPOPT_OLEN]; 1138 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1139 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1140 goto bad; 1141 } 1142 } 1143 switch (opt) { 1144 1145 default: 1146 break; 1147 1148 /* 1149 * Source routing with record. 1150 * Find interface with current destination address. 1151 * If none on this machine then drop if strictly routed, 1152 * or do nothing if loosely routed. 1153 * Record interface address and bring up next address 1154 * component. If strictly routed make sure next 1155 * address is on directly accessible net. 1156 */ 1157 case IPOPT_LSRR: 1158 case IPOPT_SSRR: 1159 if (ip_allowsrcrt == 0) { 1160 type = ICMP_UNREACH; 1161 code = ICMP_UNREACH_NET_PROHIB; 1162 goto bad; 1163 } 1164 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1165 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1166 goto bad; 1167 } 1168 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1169 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1170 goto bad; 1171 } 1172 ipaddr.sin_addr = ip->ip_dst; 1173 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1174 if (ia == 0) { 1175 if (opt == IPOPT_SSRR) { 1176 type = ICMP_UNREACH; 1177 code = ICMP_UNREACH_SRCFAIL; 1178 goto bad; 1179 } 1180 /* 1181 * Loose routing, and not at next destination 1182 * yet; nothing to do except forward. 1183 */ 1184 break; 1185 } 1186 off--; /* 0 origin */ 1187 if ((off + sizeof(struct in_addr)) > optlen) { 1188 /* 1189 * End of source route. Should be for us. 1190 */ 1191 save_rte(cp, ip->ip_src); 1192 break; 1193 } 1194 /* 1195 * locate outgoing interface 1196 */ 1197 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 1198 sizeof(ipaddr.sin_addr)); 1199 if (opt == IPOPT_SSRR) 1200 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1201 else 1202 ia = ip_rtaddr(ipaddr.sin_addr); 1203 if (ia == 0) { 1204 type = ICMP_UNREACH; 1205 code = ICMP_UNREACH_SRCFAIL; 1206 goto bad; 1207 } 1208 ip->ip_dst = ipaddr.sin_addr; 1209 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1210 (caddr_t)(cp + off), sizeof(struct in_addr)); 1211 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1212 /* 1213 * Let ip_intr's mcast routing check handle mcast pkts 1214 */ 1215 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1216 break; 1217 1218 case IPOPT_RR: 1219 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1220 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1221 goto bad; 1222 } 1223 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1224 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1225 goto bad; 1226 } 1227 /* 1228 * If no space remains, ignore. 1229 */ 1230 off--; /* 0 origin */ 1231 if ((off + sizeof(struct in_addr)) > optlen) 1232 break; 1233 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 1234 sizeof(ipaddr.sin_addr)); 1235 /* 1236 * locate outgoing interface; if we're the destination, 1237 * use the incoming interface (should be same). 1238 */ 1239 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1240 == NULL && 1241 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1242 type = ICMP_UNREACH; 1243 code = ICMP_UNREACH_HOST; 1244 goto bad; 1245 } 1246 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1247 (caddr_t)(cp + off), sizeof(struct in_addr)); 1248 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1249 break; 1250 1251 case IPOPT_TS: 1252 code = cp - (u_char *)ip; 1253 ipt = (struct ip_timestamp *)cp; 1254 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1255 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1256 goto bad; 1257 } 1258 if (ipt->ipt_ptr < 5) { 1259 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1260 goto bad; 1261 } 1262 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1263 if (++ipt->ipt_oflw == 0) { 1264 code = (u_char *)&ipt->ipt_ptr - 1265 (u_char *)ip; 1266 goto bad; 1267 } 1268 break; 1269 } 1270 cp0 = (cp + ipt->ipt_ptr - 1); 1271 switch (ipt->ipt_flg) { 1272 1273 case IPOPT_TS_TSONLY: 1274 break; 1275 1276 case IPOPT_TS_TSANDADDR: 1277 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1278 sizeof(struct in_addr) > ipt->ipt_len) { 1279 code = (u_char *)&ipt->ipt_ptr - 1280 (u_char *)ip; 1281 goto bad; 1282 } 1283 ipaddr.sin_addr = dst; 1284 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1285 m->m_pkthdr.rcvif)); 1286 if (ia == 0) 1287 continue; 1288 bcopy(&ia->ia_addr.sin_addr, 1289 cp0, sizeof(struct in_addr)); 1290 ipt->ipt_ptr += sizeof(struct in_addr); 1291 break; 1292 1293 case IPOPT_TS_PRESPEC: 1294 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1295 sizeof(struct in_addr) > ipt->ipt_len) { 1296 code = (u_char *)&ipt->ipt_ptr - 1297 (u_char *)ip; 1298 goto bad; 1299 } 1300 bcopy(cp0, &ipaddr.sin_addr, 1301 sizeof(struct in_addr)); 1302 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1303 == NULL) 1304 continue; 1305 ipt->ipt_ptr += sizeof(struct in_addr); 1306 break; 1307 1308 default: 1309 /* XXX can't take &ipt->ipt_flg */ 1310 code = (u_char *)&ipt->ipt_ptr - 1311 (u_char *)ip + 1; 1312 goto bad; 1313 } 1314 ntime = iptime(); 1315 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1316 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1, 1317 sizeof(n_time)); 1318 ipt->ipt_ptr += sizeof(n_time); 1319 } 1320 } 1321 if (forward) { 1322 if (ip_forwsrcrt == 0) { 1323 type = ICMP_UNREACH; 1324 code = ICMP_UNREACH_SRCFAIL; 1325 goto bad; 1326 } 1327 ip_forward(m, 1); 1328 return (1); 1329 } 1330 return (0); 1331bad: 1332 icmp_error(m, type, code, 0, 0); 1333 ipstat.ips_badoptions++; 1334 return (1); 1335} 1336 1337/* 1338 * Given address of next destination (final or next hop), 1339 * return internet address info of interface to be used to get there. 1340 */ 1341struct in_ifaddr * 1342ip_rtaddr(dst) 1343 struct in_addr dst; 1344{ 1345 struct sockaddr_in *sin; 1346 1347 sin = satosin(&ipforward_rt.ro_dst); 1348 1349 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 1350 if (ipforward_rt.ro_rt) { 1351 RTFREE(ipforward_rt.ro_rt); 1352 ipforward_rt.ro_rt = 0; 1353 } 1354 sin->sin_family = AF_INET; 1355 sin->sin_len = sizeof(*sin); 1356 sin->sin_addr = dst; 1357 1358 rtalloc(&ipforward_rt); 1359 } 1360 if (ipforward_rt.ro_rt == 0) 1361 return ((struct in_ifaddr *)0); 1362 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 1363} 1364 1365/* 1366 * Save incoming source route for use in replies, 1367 * to be picked up later by ip_srcroute if the receiver is interested. 1368 */ 1369void 1370save_rte(option, dst) 1371 u_char *option; 1372 struct in_addr dst; 1373{ 1374 unsigned olen; 1375 1376 olen = option[IPOPT_OLEN]; 1377#ifdef DIAGNOSTIC 1378 if (ipprintfs) 1379 printf("save_rte: olen %d\n", olen); 1380#endif /* 0 */ 1381 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1382 return; 1383 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1384 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1385 ip_srcrt.dst = dst; 1386} 1387 1388/* 1389 * Retrieve incoming source route for use in replies, 1390 * in the same form used by setsockopt. 1391 * The first hop is placed before the options, will be removed later. 1392 */ 1393struct mbuf * 1394ip_srcroute() 1395{ 1396 struct in_addr *p, *q; 1397 struct mbuf *m; 1398 1399 if (ip_nhops == 0) 1400 return ((struct mbuf *)0); 1401 m = m_get(M_DONTWAIT, MT_SOOPTS); 1402 if (m == 0) 1403 return ((struct mbuf *)0); 1404 1405 MCLAIM(m, &inetdomain.dom_mowner); 1406#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1407 1408 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1409 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1410 OPTSIZ; 1411#ifdef DIAGNOSTIC 1412 if (ipprintfs) 1413 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1414#endif 1415 1416 /* 1417 * First save first hop for return route 1418 */ 1419 p = &ip_srcrt.route[ip_nhops - 1]; 1420 *(mtod(m, struct in_addr *)) = *p--; 1421#ifdef DIAGNOSTIC 1422 if (ipprintfs) 1423 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1424#endif 1425 1426 /* 1427 * Copy option fields and padding (nop) to mbuf. 1428 */ 1429 ip_srcrt.nop = IPOPT_NOP; 1430 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1431 bcopy((caddr_t)&ip_srcrt.nop, 1432 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1433 q = (struct in_addr *)(mtod(m, caddr_t) + 1434 sizeof(struct in_addr) + OPTSIZ); 1435#undef OPTSIZ 1436 /* 1437 * Record return path as an IP source route, 1438 * reversing the path (pointers are now aligned). 1439 */ 1440 while (p >= ip_srcrt.route) { 1441#ifdef DIAGNOSTIC 1442 if (ipprintfs) 1443 printf(" %x", ntohl(q->s_addr)); 1444#endif 1445 *q++ = *p--; 1446 } 1447 /* 1448 * Last hop goes to final destination. 1449 */ 1450 *q = ip_srcrt.dst; 1451#ifdef DIAGNOSTIC 1452 if (ipprintfs) 1453 printf(" %x\n", ntohl(q->s_addr)); 1454#endif 1455 return (m); 1456} 1457 1458/* 1459 * Strip out IP options, at higher 1460 * level protocol in the kernel. 1461 * Second argument is buffer to which options 1462 * will be moved, and return value is their length. 1463 * XXX should be deleted; last arg currently ignored. 1464 */ 1465void 1466ip_stripoptions(m, mopt) 1467 struct mbuf *m; 1468 struct mbuf *mopt; 1469{ 1470 int i; 1471 struct ip *ip = mtod(m, struct ip *); 1472 caddr_t opts; 1473 int olen; 1474 1475 olen = (ip->ip_hl << 2) - sizeof (struct ip); 1476 opts = (caddr_t)(ip + 1); 1477 i = m->m_len - (sizeof (struct ip) + olen); 1478 bcopy(opts + olen, opts, (unsigned)i); 1479 m->m_len -= olen; 1480 if (m->m_flags & M_PKTHDR) 1481 m->m_pkthdr.len -= olen; 1482 ip->ip_len = htons(ntohs(ip->ip_len) - olen); 1483 ip->ip_hl = sizeof (struct ip) >> 2; 1484} 1485 1486const int inetctlerrmap[PRC_NCMDS] = { 1487 0, 0, 0, 0, 1488 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1489 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1490 EMSGSIZE, EHOSTUNREACH, 0, 0, 1491 0, 0, 0, 0, 1492 ENOPROTOOPT 1493}; 1494 1495/* 1496 * Forward a packet. If some error occurs return the sender 1497 * an icmp packet. Note we can't always generate a meaningful 1498 * icmp message because icmp doesn't have a large enough repertoire 1499 * of codes and types. 1500 * 1501 * If not forwarding, just drop the packet. This could be confusing 1502 * if ipforwarding was zero but some routing protocol was advancing 1503 * us as a gateway to somewhere. However, we must let the routing 1504 * protocol deal with that. 1505 * 1506 * The srcrt parameter indicates whether the packet is being forwarded 1507 * via a source route. 1508 */ 1509void 1510ip_forward(m, srcrt) 1511 struct mbuf *m; 1512 int srcrt; 1513{ 1514 struct ip *ip = mtod(m, struct ip *); 1515 struct sockaddr_in *sin; 1516 struct rtentry *rt; 1517 int error, type = 0, code = 0; 1518 struct mbuf *mcopy; 1519 n_long dest; 1520 struct ifnet *destifp; 1521#ifdef IPSEC 1522 struct ifnet dummyifp; 1523#endif 1524 1525 /* 1526 * We are now in the output path. 1527 */ 1528 MCLAIM(m, &ip_tx_mowner); 1529 1530 /* 1531 * Clear any in-bound checksum flags for this packet. 1532 */ 1533 m->m_pkthdr.csum_flags = 0; 1534 1535 dest = 0; 1536#ifdef DIAGNOSTIC 1537 if (ipprintfs) 1538 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1539 ntohl(ip->ip_src.s_addr), 1540 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1541#endif 1542 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1543 ipstat.ips_cantforward++; 1544 m_freem(m); 1545 return; 1546 } 1547 if (ip->ip_ttl <= IPTTLDEC) { 1548 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1549 return; 1550 } 1551 ip->ip_ttl -= IPTTLDEC; 1552 1553 sin = satosin(&ipforward_rt.ro_dst); 1554 if ((rt = ipforward_rt.ro_rt) == 0 || 1555 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1556 if (ipforward_rt.ro_rt) { 1557 RTFREE(ipforward_rt.ro_rt); 1558 ipforward_rt.ro_rt = 0; 1559 } 1560 sin->sin_family = AF_INET; 1561 sin->sin_len = sizeof(struct sockaddr_in); 1562 sin->sin_addr = ip->ip_dst; 1563 1564 rtalloc(&ipforward_rt); 1565 if (ipforward_rt.ro_rt == 0) { 1566 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1567 return; 1568 } 1569 rt = ipforward_rt.ro_rt; 1570 } 1571 1572 /* 1573 * Save at most 68 bytes of the packet in case 1574 * we need to generate an ICMP message to the src. 1575 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1576 */ 1577 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1578 if (mcopy) 1579 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1580 1581 /* 1582 * If forwarding packet using same interface that it came in on, 1583 * perhaps should send a redirect to sender to shortcut a hop. 1584 * Only send redirect if source is sending directly to us, 1585 * and if packet was not source routed (or has any options). 1586 * Also, don't send redirect if forwarding using a default route 1587 * or a route modified by a redirect. 1588 */ 1589 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1590 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1591 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1592 ipsendredirects && !srcrt) { 1593 if (rt->rt_ifa && 1594 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1595 ifatoia(rt->rt_ifa)->ia_subnet) { 1596 if (rt->rt_flags & RTF_GATEWAY) 1597 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1598 else 1599 dest = ip->ip_dst.s_addr; 1600 /* 1601 * Router requirements says to only send host 1602 * redirects. 1603 */ 1604 type = ICMP_REDIRECT; 1605 code = ICMP_REDIRECT_HOST; 1606#ifdef DIAGNOSTIC 1607 if (ipprintfs) 1608 printf("redirect (%d) to %x\n", code, 1609 (u_int32_t)dest); 1610#endif 1611 } 1612 } 1613 1614#ifdef IPSEC 1615 /* Don't lookup socket in forwarding case */ 1616 (void)ipsec_setsocket(m, NULL); 1617#endif 1618 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1619 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1620 if (error) 1621 ipstat.ips_cantforward++; 1622 else { 1623 ipstat.ips_forward++; 1624 if (type) 1625 ipstat.ips_redirectsent++; 1626 else { 1627 if (mcopy) { 1628#ifdef GATEWAY 1629 if (mcopy->m_flags & M_CANFASTFWD) 1630 ipflow_create(&ipforward_rt, mcopy); 1631#endif 1632 m_freem(mcopy); 1633 } 1634 return; 1635 } 1636 } 1637 if (mcopy == NULL) 1638 return; 1639 destifp = NULL; 1640 1641 switch (error) { 1642 1643 case 0: /* forwarded, but need redirect */ 1644 /* type, code set above */ 1645 break; 1646 1647 case ENETUNREACH: /* shouldn't happen, checked above */ 1648 case EHOSTUNREACH: 1649 case ENETDOWN: 1650 case EHOSTDOWN: 1651 default: 1652 type = ICMP_UNREACH; 1653 code = ICMP_UNREACH_HOST; 1654 break; 1655 1656 case EMSGSIZE: 1657 type = ICMP_UNREACH; 1658 code = ICMP_UNREACH_NEEDFRAG; 1659#ifndef IPSEC 1660 if (ipforward_rt.ro_rt) 1661 destifp = ipforward_rt.ro_rt->rt_ifp; 1662#else 1663 /* 1664 * If the packet is routed over IPsec tunnel, tell the 1665 * originator the tunnel MTU. 1666 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1667 * XXX quickhack!!! 1668 */ 1669 if (ipforward_rt.ro_rt) { 1670 struct secpolicy *sp; 1671 int ipsecerror; 1672 size_t ipsechdr; 1673 struct route *ro; 1674 1675 sp = ipsec4_getpolicybyaddr(mcopy, 1676 IPSEC_DIR_OUTBOUND, 1677 IP_FORWARDING, 1678 &ipsecerror); 1679 1680 if (sp == NULL) 1681 destifp = ipforward_rt.ro_rt->rt_ifp; 1682 else { 1683 /* count IPsec header size */ 1684 ipsechdr = ipsec4_hdrsiz(mcopy, 1685 IPSEC_DIR_OUTBOUND, 1686 NULL); 1687 1688 /* 1689 * find the correct route for outer IPv4 1690 * header, compute tunnel MTU. 1691 * 1692 * XXX BUG ALERT 1693 * The "dummyifp" code relies upon the fact 1694 * that icmp_error() touches only ifp->if_mtu. 1695 */ 1696 /*XXX*/ 1697 destifp = NULL; 1698 if (sp->req != NULL 1699 && sp->req->sav != NULL 1700 && sp->req->sav->sah != NULL) { 1701 ro = &sp->req->sav->sah->sa_route; 1702 if (ro->ro_rt && ro->ro_rt->rt_ifp) { 1703 dummyifp.if_mtu = 1704 ro->ro_rt->rt_rmx.rmx_mtu ? 1705 ro->ro_rt->rt_rmx.rmx_mtu : 1706 ro->ro_rt->rt_ifp->if_mtu; 1707 dummyifp.if_mtu -= ipsechdr; 1708 destifp = &dummyifp; 1709 } 1710 } 1711 1712 key_freesp(sp); 1713 } 1714 } 1715#endif /*IPSEC*/ 1716 ipstat.ips_cantfrag++; 1717 break; 1718 1719 case ENOBUFS: 1720#if 1 1721 /* 1722 * a router should not generate ICMP_SOURCEQUENCH as 1723 * required in RFC1812 Requirements for IP Version 4 Routers. 1724 * source quench could be a big problem under DoS attacks, 1725 * or if the underlying interface is rate-limited. 1726 */ 1727 if (mcopy) 1728 m_freem(mcopy); 1729 return; 1730#else 1731 type = ICMP_SOURCEQUENCH; 1732 code = 0; 1733 break; 1734#endif 1735 } 1736 icmp_error(mcopy, type, code, dest, destifp); 1737} 1738 1739void 1740ip_savecontrol(inp, mp, ip, m) 1741 struct inpcb *inp; 1742 struct mbuf **mp; 1743 struct ip *ip; 1744 struct mbuf *m; 1745{ 1746 1747 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1748 struct timeval tv; 1749 1750 microtime(&tv); 1751 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1752 SCM_TIMESTAMP, SOL_SOCKET); 1753 if (*mp) 1754 mp = &(*mp)->m_next; 1755 } 1756 if (inp->inp_flags & INP_RECVDSTADDR) { 1757 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1758 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1759 if (*mp) 1760 mp = &(*mp)->m_next; 1761 } 1762#ifdef notyet 1763 /* 1764 * XXX 1765 * Moving these out of udp_input() made them even more broken 1766 * than they already were. 1767 * - fenner@parc.xerox.com 1768 */ 1769 /* options were tossed already */ 1770 if (inp->inp_flags & INP_RECVOPTS) { 1771 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1772 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1773 if (*mp) 1774 mp = &(*mp)->m_next; 1775 } 1776 /* ip_srcroute doesn't do what we want here, need to fix */ 1777 if (inp->inp_flags & INP_RECVRETOPTS) { 1778 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1779 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1780 if (*mp) 1781 mp = &(*mp)->m_next; 1782 } 1783#endif 1784 if (inp->inp_flags & INP_RECVIF) { 1785 struct sockaddr_dl sdl; 1786 1787 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1788 sdl.sdl_family = AF_LINK; 1789 sdl.sdl_index = m->m_pkthdr.rcvif ? 1790 m->m_pkthdr.rcvif->if_index : 0; 1791 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1792 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1793 IP_RECVIF, IPPROTO_IP); 1794 if (*mp) 1795 mp = &(*mp)->m_next; 1796 } 1797} 1798 1799int 1800ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1801 int *name; 1802 u_int namelen; 1803 void *oldp; 1804 size_t *oldlenp; 1805 void *newp; 1806 size_t newlen; 1807{ 1808 extern int subnetsarelocal, hostzeroisbroadcast; 1809 1810 int error, old; 1811 1812 /* All sysctl names at this level are terminal. */ 1813 if (namelen != 1) 1814 return (ENOTDIR); 1815 1816 switch (name[0]) { 1817 case IPCTL_FORWARDING: 1818 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1819 case IPCTL_SENDREDIRECTS: 1820 return (sysctl_int(oldp, oldlenp, newp, newlen, 1821 &ipsendredirects)); 1822 case IPCTL_DEFTTL: 1823 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1824#ifdef notyet 1825 case IPCTL_DEFMTU: 1826 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1827#endif 1828 case IPCTL_FORWSRCRT: 1829 /* Don't allow this to change in a secure environment. */ 1830 if (securelevel > 0) 1831 return (sysctl_rdint(oldp, oldlenp, newp, 1832 ip_forwsrcrt)); 1833 else 1834 return (sysctl_int(oldp, oldlenp, newp, newlen, 1835 &ip_forwsrcrt)); 1836 case IPCTL_DIRECTEDBCAST: 1837 return (sysctl_int(oldp, oldlenp, newp, newlen, 1838 &ip_directedbcast)); 1839 case IPCTL_ALLOWSRCRT: 1840 return (sysctl_int(oldp, oldlenp, newp, newlen, 1841 &ip_allowsrcrt)); 1842 case IPCTL_SUBNETSARELOCAL: 1843 return (sysctl_int(oldp, oldlenp, newp, newlen, 1844 &subnetsarelocal)); 1845 case IPCTL_MTUDISC: 1846 error = sysctl_int(oldp, oldlenp, newp, newlen, 1847 &ip_mtudisc); 1848 if (error == 0 && ip_mtudisc == 0) 1849 rt_timer_queue_remove_all(ip_mtudisc_timeout_q, TRUE); 1850 return error; 1851 case IPCTL_ANONPORTMIN: 1852 old = anonportmin; 1853 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1854 if (anonportmin >= anonportmax || anonportmin < 0 1855 || anonportmin > 65535 1856#ifndef IPNOPRIVPORTS 1857 || anonportmin < IPPORT_RESERVED 1858#endif 1859 ) { 1860 anonportmin = old; 1861 return (EINVAL); 1862 } 1863 return (error); 1864 case IPCTL_ANONPORTMAX: 1865 old = anonportmax; 1866 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1867 if (anonportmin >= anonportmax || anonportmax < 0 1868 || anonportmax > 65535 1869#ifndef IPNOPRIVPORTS 1870 || anonportmax < IPPORT_RESERVED 1871#endif 1872 ) { 1873 anonportmax = old; 1874 return (EINVAL); 1875 } 1876 return (error); 1877 case IPCTL_MTUDISCTIMEOUT: 1878 old = ip_mtudisc_timeout; 1879 error = sysctl_int(oldp, oldlenp, newp, newlen, 1880 &ip_mtudisc_timeout); 1881 if (ip_mtudisc_timeout < 0) { 1882 ip_mtudisc_timeout = old; 1883 return (EINVAL); 1884 } 1885 if (error == 0) 1886 rt_timer_queue_change(ip_mtudisc_timeout_q, 1887 ip_mtudisc_timeout); 1888 return (error); 1889#ifdef GATEWAY 1890 case IPCTL_MAXFLOWS: 1891 { 1892 int s; 1893 1894 error = sysctl_int(oldp, oldlenp, newp, newlen, 1895 &ip_maxflows); 1896 s = splsoftnet(); 1897 ipflow_reap(0); 1898 splx(s); 1899 return (error); 1900 } 1901#endif 1902 case IPCTL_HOSTZEROBROADCAST: 1903 return (sysctl_int(oldp, oldlenp, newp, newlen, 1904 &hostzeroisbroadcast)); 1905#if NGIF > 0 1906 case IPCTL_GIF_TTL: 1907 return (sysctl_int(oldp, oldlenp, newp, newlen, 1908 &ip_gif_ttl)); 1909#endif 1910 1911#if NGRE > 0 1912 case IPCTL_GRE_TTL: 1913 return (sysctl_int(oldp, oldlenp, newp, newlen, 1914 &ip_gre_ttl)); 1915#endif 1916 1917#ifndef IPNOPRIVPORTS 1918 case IPCTL_LOWPORTMIN: 1919 old = lowportmin; 1920 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin); 1921 if (lowportmin >= lowportmax 1922 || lowportmin > IPPORT_RESERVEDMAX 1923 || lowportmin < IPPORT_RESERVEDMIN 1924 ) { 1925 lowportmin = old; 1926 return (EINVAL); 1927 } 1928 return (error); 1929 case IPCTL_LOWPORTMAX: 1930 old = lowportmax; 1931 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax); 1932 if (lowportmin >= lowportmax 1933 || lowportmax > IPPORT_RESERVEDMAX 1934 || lowportmax < IPPORT_RESERVEDMIN 1935 ) { 1936 lowportmax = old; 1937 return (EINVAL); 1938 } 1939 return (error); 1940#endif 1941 1942 case IPCTL_MAXFRAGPACKETS: 1943 return (sysctl_int(oldp, oldlenp, newp, newlen, 1944 &ip_maxfragpackets)); 1945 1946 default: 1947 return (EOPNOTSUPP); 1948 } 1949 /* NOTREACHED */ 1950} 1951