ip_input.c revision 1.276
1/* $NetBSD: ip_input.c,v 1.276 2008/11/23 19:52:38 rmind 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 * 49 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 50 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 51 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 52 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 53 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 54 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 55 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 56 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 57 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 58 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 59 * POSSIBILITY OF SUCH DAMAGE. 60 */ 61 62/* 63 * Copyright (c) 1982, 1986, 1988, 1993 64 * The Regents of the University of California. All rights reserved. 65 * 66 * Redistribution and use in source and binary forms, with or without 67 * modification, are permitted provided that the following conditions 68 * are met: 69 * 1. Redistributions of source code must retain the above copyright 70 * notice, this list of conditions and the following disclaimer. 71 * 2. Redistributions in binary form must reproduce the above copyright 72 * notice, this list of conditions and the following disclaimer in the 73 * documentation and/or other materials provided with the distribution. 74 * 3. Neither the name of the University nor the names of its contributors 75 * may be used to endorse or promote products derived from this software 76 * without specific prior written permission. 77 * 78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 81 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 88 * SUCH DAMAGE. 89 * 90 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 91 */ 92 93#include <sys/cdefs.h> 94__KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.276 2008/11/23 19:52:38 rmind Exp $"); 95 96#include "opt_inet.h" 97#include "opt_gateway.h" 98#include "opt_pfil_hooks.h" 99#include "opt_ipsec.h" 100#include "opt_mrouting.h" 101#include "opt_mbuftrace.h" 102#include "opt_inet_csum.h" 103 104#include <sys/param.h> 105#include <sys/systm.h> 106#include <sys/malloc.h> 107#include <sys/mbuf.h> 108#include <sys/domain.h> 109#include <sys/protosw.h> 110#include <sys/socket.h> 111#include <sys/socketvar.h> 112#include <sys/errno.h> 113#include <sys/time.h> 114#include <sys/kernel.h> 115#include <sys/pool.h> 116#include <sys/sysctl.h> 117#include <sys/kauth.h> 118 119#include <net/if.h> 120#include <net/if_dl.h> 121#include <net/route.h> 122#include <net/pfil.h> 123 124#include <netinet/in.h> 125#include <netinet/in_systm.h> 126#include <netinet/ip.h> 127#include <netinet/in_pcb.h> 128#include <netinet/in_proto.h> 129#include <netinet/in_var.h> 130#include <netinet/ip_var.h> 131#include <netinet/ip_private.h> 132#include <netinet/ip_icmp.h> 133/* just for gif_ttl */ 134#include <netinet/in_gif.h> 135#include "gif.h" 136#include <net/if_gre.h> 137#include "gre.h" 138 139#ifdef MROUTING 140#include <netinet/ip_mroute.h> 141#endif 142 143#ifdef IPSEC 144#include <netinet6/ipsec.h> 145#include <netinet6/ipsec_private.h> 146#include <netkey/key.h> 147#endif 148#ifdef FAST_IPSEC 149#include <netipsec/ipsec.h> 150#include <netipsec/key.h> 151#endif /* FAST_IPSEC*/ 152 153#ifndef IPFORWARDING 154#ifdef GATEWAY 155#define IPFORWARDING 1 /* forward IP packets not for us */ 156#else /* GATEWAY */ 157#define IPFORWARDING 0 /* don't forward IP packets not for us */ 158#endif /* GATEWAY */ 159#endif /* IPFORWARDING */ 160#ifndef IPSENDREDIRECTS 161#define IPSENDREDIRECTS 1 162#endif 163#ifndef IPFORWSRCRT 164#define IPFORWSRCRT 1 /* forward source-routed packets */ 165#endif 166#ifndef IPALLOWSRCRT 167#define IPALLOWSRCRT 1 /* allow source-routed packets */ 168#endif 169#ifndef IPMTUDISC 170#define IPMTUDISC 1 171#endif 172#ifndef IPMTUDISCTIMEOUT 173#define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 174#endif 175 176/* 177 * Note: DIRECTED_BROADCAST is handled this way so that previous 178 * configuration using this option will Just Work. 179 */ 180#ifndef IPDIRECTEDBCAST 181#ifdef DIRECTED_BROADCAST 182#define IPDIRECTEDBCAST 1 183#else 184#define IPDIRECTEDBCAST 0 185#endif /* DIRECTED_BROADCAST */ 186#endif /* IPDIRECTEDBCAST */ 187int ipforwarding = IPFORWARDING; 188int ipsendredirects = IPSENDREDIRECTS; 189int ip_defttl = IPDEFTTL; 190int ip_forwsrcrt = IPFORWSRCRT; 191int ip_directedbcast = IPDIRECTEDBCAST; 192int ip_allowsrcrt = IPALLOWSRCRT; 193int ip_mtudisc = IPMTUDISC; 194int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 195#ifdef DIAGNOSTIC 196int ipprintfs = 0; 197#endif 198 199int ip_do_randomid = 0; 200 201/* 202 * XXX - Setting ip_checkinterface mostly implements the receive side of 203 * the Strong ES model described in RFC 1122, but since the routing table 204 * and transmit implementation do not implement the Strong ES model, 205 * setting this to 1 results in an odd hybrid. 206 * 207 * XXX - ip_checkinterface currently must be disabled if you use ipnat 208 * to translate the destination address to another local interface. 209 * 210 * XXX - ip_checkinterface must be disabled if you add IP aliases 211 * to the loopback interface instead of the interface where the 212 * packets for those addresses are received. 213 */ 214int ip_checkinterface = 0; 215 216 217struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 218 219int ipqmaxlen = IFQ_MAXLEN; 220u_long in_ifaddrhash; /* size of hash table - 1 */ 221int in_ifaddrentries; /* total number of addrs */ 222struct in_ifaddrhead in_ifaddrhead; 223struct in_ifaddrhashhead *in_ifaddrhashtbl; 224u_long in_multihash; /* size of hash table - 1 */ 225int in_multientries; /* total number of addrs */ 226struct in_multihashhead *in_multihashtbl; 227struct ifqueue ipintrq; 228uint16_t ip_id; 229 230percpu_t *ipstat_percpu; 231 232#ifdef PFIL_HOOKS 233struct pfil_head inet_pfil_hook; 234#endif 235 236/* 237 * Cached copy of nmbclusters. If nbclusters is different, 238 * recalculate IP parameters derived from nmbclusters. 239 */ 240static int ip_nmbclusters; /* copy of nmbclusters */ 241static void ip_nmbclusters_changed(void); /* recalc limits */ 242 243#define CHECK_NMBCLUSTER_PARAMS() \ 244do { \ 245 if (__predict_false(ip_nmbclusters != nmbclusters)) \ 246 ip_nmbclusters_changed(); \ 247} while (/*CONSTCOND*/0) 248 249/* IP datagram reassembly queues (hashed) */ 250#define IPREASS_NHASH_LOG2 6 251#define IPREASS_NHASH (1 << IPREASS_NHASH_LOG2) 252#define IPREASS_HMASK (IPREASS_NHASH - 1) 253#define IPREASS_HASH(x,y) \ 254 (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK) 255struct ipqhead ipq[IPREASS_NHASH]; 256int ipq_locked; 257static int ip_nfragpackets; /* packets in reass queue */ 258static int ip_nfrags; /* total fragments in reass queues */ 259 260int ip_maxfragpackets = 200; /* limit on packets. XXX sysctl */ 261int ip_maxfrags; /* limit on fragments. XXX sysctl */ 262 263 264/* 265 * Additive-Increase/Multiplicative-Decrease (AIMD) strategy for 266 * IP reassembly queue buffer managment. 267 * 268 * We keep a count of total IP fragments (NB: not fragmented packets!) 269 * awaiting reassembly (ip_nfrags) and a limit (ip_maxfrags) on fragments. 270 * If ip_nfrags exceeds ip_maxfrags the limit, we drop half the 271 * total fragments in reassembly queues.This AIMD policy avoids 272 * repeatedly deleting single packets under heavy fragmentation load 273 * (e.g., from lossy NFS peers). 274 */ 275static u_int ip_reass_ttl_decr(u_int ticks); 276static void ip_reass_drophalf(void); 277 278 279static inline int ipq_lock_try(void); 280static inline void ipq_unlock(void); 281 282static inline int 283ipq_lock_try(void) 284{ 285 int s; 286 287 /* 288 * Use splvm() -- we're blocking things that would cause 289 * mbuf allocation. 290 */ 291 s = splvm(); 292 if (ipq_locked) { 293 splx(s); 294 return (0); 295 } 296 ipq_locked = 1; 297 splx(s); 298 return (1); 299} 300 301static inline void 302ipq_unlock(void) 303{ 304 int s; 305 306 s = splvm(); 307 ipq_locked = 0; 308 splx(s); 309} 310 311#ifdef DIAGNOSTIC 312#define IPQ_LOCK() \ 313do { \ 314 if (ipq_lock_try() == 0) { \ 315 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 316 panic("ipq_lock"); \ 317 } \ 318} while (/*CONSTCOND*/ 0) 319#define IPQ_LOCK_CHECK() \ 320do { \ 321 if (ipq_locked == 0) { \ 322 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 323 panic("ipq lock check"); \ 324 } \ 325} while (/*CONSTCOND*/ 0) 326#else 327#define IPQ_LOCK() (void) ipq_lock_try() 328#define IPQ_LOCK_CHECK() /* nothing */ 329#endif 330 331#define IPQ_UNLOCK() ipq_unlock() 332 333struct pool inmulti_pool; 334struct pool ipqent_pool; 335 336#ifdef INET_CSUM_COUNTERS 337#include <sys/device.h> 338 339struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 340 NULL, "inet", "hwcsum bad"); 341struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 342 NULL, "inet", "hwcsum ok"); 343struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 344 NULL, "inet", "swcsum"); 345 346#define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 347 348EVCNT_ATTACH_STATIC(ip_hwcsum_bad); 349EVCNT_ATTACH_STATIC(ip_hwcsum_ok); 350EVCNT_ATTACH_STATIC(ip_swcsum); 351 352#else 353 354#define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 355 356#endif /* INET_CSUM_COUNTERS */ 357 358/* 359 * We need to save the IP options in case a protocol wants to respond 360 * to an incoming packet over the same route if the packet got here 361 * using IP source routing. This allows connection establishment and 362 * maintenance when the remote end is on a network that is not known 363 * to us. 364 */ 365int ip_nhops = 0; 366static struct ip_srcrt { 367 struct in_addr dst; /* final destination */ 368 char nop; /* one NOP to align */ 369 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 370 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 371} ip_srcrt; 372 373static void save_rte(u_char *, struct in_addr); 374 375#ifdef MBUFTRACE 376struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx"); 377struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx"); 378#endif 379 380/* 381 * Compute IP limits derived from the value of nmbclusters. 382 */ 383static void 384ip_nmbclusters_changed(void) 385{ 386 ip_maxfrags = nmbclusters / 4; 387 ip_nmbclusters = nmbclusters; 388} 389 390/* 391 * IP initialization: fill in IP protocol switch table. 392 * All protocols not implemented in kernel go to raw IP protocol handler. 393 */ 394void 395ip_init(void) 396{ 397 const struct protosw *pr; 398 int i; 399 400 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", 401 NULL, IPL_SOFTNET); 402 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 403 NULL, IPL_VM); 404 405 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 406 if (pr == 0) 407 panic("ip_init"); 408 for (i = 0; i < IPPROTO_MAX; i++) 409 ip_protox[i] = pr - inetsw; 410 for (pr = inetdomain.dom_protosw; 411 pr < inetdomain.dom_protoswNPROTOSW; pr++) 412 if (pr->pr_domain->dom_family == PF_INET && 413 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 414 ip_protox[pr->pr_protocol] = pr - inetsw; 415 416 for (i = 0; i < IPREASS_NHASH; i++) 417 LIST_INIT(&ipq[i]); 418 419 ip_initid(); 420 ip_id = time_second & 0xfffff; 421 422 ipintrq.ifq_maxlen = ipqmaxlen; 423 ip_nmbclusters_changed(); 424 425 TAILQ_INIT(&in_ifaddrhead); 426 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 427 &in_ifaddrhash); 428 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 429 &in_multihash); 430 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 431#ifdef GATEWAY 432 ipflow_init(ip_hashsize); 433#endif 434 435#ifdef PFIL_HOOKS 436 /* Register our Packet Filter hook. */ 437 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 438 inet_pfil_hook.ph_af = AF_INET; 439 i = pfil_head_register(&inet_pfil_hook); 440 if (i != 0) 441 printf("ip_init: WARNING: unable to register pfil hook, " 442 "error %d\n", i); 443#endif /* PFIL_HOOKS */ 444 445#ifdef MBUFTRACE 446 MOWNER_ATTACH(&ip_tx_mowner); 447 MOWNER_ATTACH(&ip_rx_mowner); 448#endif /* MBUFTRACE */ 449 450 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS); 451} 452 453struct sockaddr_in ipaddr = { 454 .sin_len = sizeof(ipaddr), 455 .sin_family = AF_INET, 456}; 457struct route ipforward_rt; 458 459/* 460 * IP software interrupt routine 461 */ 462void 463ipintr(void) 464{ 465 int s; 466 struct mbuf *m; 467 468 mutex_enter(softnet_lock); 469 KERNEL_LOCK(1, NULL); 470 while (!IF_IS_EMPTY(&ipintrq)) { 471 s = splnet(); 472 IF_DEQUEUE(&ipintrq, m); 473 splx(s); 474 if (m == NULL) 475 break; 476 ip_input(m); 477 } 478 KERNEL_UNLOCK_ONE(NULL); 479 mutex_exit(softnet_lock); 480} 481 482/* 483 * Ip input routine. Checksum and byte swap header. If fragmented 484 * try to reassemble. Process options. Pass to next level. 485 */ 486void 487ip_input(struct mbuf *m) 488{ 489 struct ip *ip = NULL; 490 struct ipq *fp; 491 struct in_ifaddr *ia; 492 struct ifaddr *ifa; 493 struct ipqent *ipqe; 494 int hlen = 0, mff, len; 495 int downmatch; 496 int checkif; 497 int srcrt = 0; 498 int s; 499 u_int hash; 500#ifdef FAST_IPSEC 501 struct m_tag *mtag; 502 struct tdb_ident *tdbi; 503 struct secpolicy *sp; 504 int error; 505#endif /* FAST_IPSEC */ 506 507 MCLAIM(m, &ip_rx_mowner); 508#ifdef DIAGNOSTIC 509 if ((m->m_flags & M_PKTHDR) == 0) 510 panic("ipintr no HDR"); 511#endif 512 513 /* 514 * If no IP addresses have been set yet but the interfaces 515 * are receiving, can't do anything with incoming packets yet. 516 */ 517 if (TAILQ_FIRST(&in_ifaddrhead) == 0) 518 goto bad; 519 IP_STATINC(IP_STAT_TOTAL); 520 /* 521 * If the IP header is not aligned, slurp it up into a new 522 * mbuf with space for link headers, in the event we forward 523 * it. Otherwise, if it is aligned, make sure the entire 524 * base IP header is in the first mbuf of the chain. 525 */ 526 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) { 527 if ((m = m_copyup(m, sizeof(struct ip), 528 (max_linkhdr + 3) & ~3)) == NULL) { 529 /* XXXJRT new stat, please */ 530 IP_STATINC(IP_STAT_TOOSMALL); 531 return; 532 } 533 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 534 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 535 IP_STATINC(IP_STAT_TOOSMALL); 536 return; 537 } 538 } 539 ip = mtod(m, struct ip *); 540 if (ip->ip_v != IPVERSION) { 541 IP_STATINC(IP_STAT_BADVERS); 542 goto bad; 543 } 544 hlen = ip->ip_hl << 2; 545 if (hlen < sizeof(struct ip)) { /* minimum header length */ 546 IP_STATINC(IP_STAT_BADHLEN); 547 goto bad; 548 } 549 if (hlen > m->m_len) { 550 if ((m = m_pullup(m, hlen)) == 0) { 551 IP_STATINC(IP_STAT_BADHLEN); 552 return; 553 } 554 ip = mtod(m, struct ip *); 555 } 556 557 /* 558 * RFC1122: packets with a multicast source address are 559 * not allowed. 560 */ 561 if (IN_MULTICAST(ip->ip_src.s_addr)) { 562 IP_STATINC(IP_STAT_BADADDR); 563 goto bad; 564 } 565 566 /* 127/8 must not appear on wire - RFC1122 */ 567 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 568 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 569 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 570 IP_STATINC(IP_STAT_BADADDR); 571 goto bad; 572 } 573 } 574 575 switch (m->m_pkthdr.csum_flags & 576 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 577 M_CSUM_IPv4_BAD)) { 578 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 579 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 580 goto badcsum; 581 582 case M_CSUM_IPv4: 583 /* Checksum was okay. */ 584 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 585 break; 586 587 default: 588 /* 589 * Must compute it ourselves. Maybe skip checksum on 590 * loopback interfaces. 591 */ 592 if (__predict_true(!(m->m_pkthdr.rcvif->if_flags & 593 IFF_LOOPBACK) || ip_do_loopback_cksum)) { 594 INET_CSUM_COUNTER_INCR(&ip_swcsum); 595 if (in_cksum(m, hlen) != 0) 596 goto badcsum; 597 } 598 break; 599 } 600 601 /* Retrieve the packet length. */ 602 len = ntohs(ip->ip_len); 603 604 /* 605 * Check for additional length bogosity 606 */ 607 if (len < hlen) { 608 IP_STATINC(IP_STAT_BADLEN); 609 goto bad; 610 } 611 612 /* 613 * Check that the amount of data in the buffers 614 * is as at least much as the IP header would have us expect. 615 * Trim mbufs if longer than we expect. 616 * Drop packet if shorter than we expect. 617 */ 618 if (m->m_pkthdr.len < len) { 619 IP_STATINC(IP_STAT_TOOSHORT); 620 goto bad; 621 } 622 if (m->m_pkthdr.len > len) { 623 if (m->m_len == m->m_pkthdr.len) { 624 m->m_len = len; 625 m->m_pkthdr.len = len; 626 } else 627 m_adj(m, len - m->m_pkthdr.len); 628 } 629 630#if defined(IPSEC) 631 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 632 m->m_flags &= ~M_CANFASTFWD; 633#else 634 /* 635 * Assume that we can create a fast-forward IP flow entry 636 * based on this packet. 637 */ 638 m->m_flags |= M_CANFASTFWD; 639#endif 640 641#ifdef PFIL_HOOKS 642 /* 643 * Run through list of hooks for input packets. If there are any 644 * filters which require that additional packets in the flow are 645 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 646 * Note that filters must _never_ set this flag, as another filter 647 * in the list may have previously cleared it. 648 */ 649 /* 650 * let ipfilter look at packet on the wire, 651 * not the decapsulated packet. 652 */ 653#ifdef IPSEC 654 if (!ipsec_getnhist(m)) 655#elif defined(FAST_IPSEC) 656 if (!ipsec_indone(m)) 657#else 658 if (1) 659#endif 660 { 661 struct in_addr odst; 662 663 odst = ip->ip_dst; 664 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 665 PFIL_IN) != 0) 666 return; 667 if (m == NULL) 668 return; 669 ip = mtod(m, struct ip *); 670 hlen = ip->ip_hl << 2; 671 /* 672 * XXX The setting of "srcrt" here is to prevent ip_forward() 673 * from generating ICMP redirects for packets that have 674 * been redirected by a hook back out on to the same LAN that 675 * they came from and is not an indication that the packet 676 * is being inffluenced by source routing options. This 677 * allows things like 678 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp" 679 * where tlp0 is both on the 1.1.1.0/24 network and is the 680 * default route for hosts on 1.1.1.0/24. Of course this 681 * also requires a "map tlp0 ..." to complete the story. 682 * One might argue whether or not this kind of network config. 683 * should be supported in this manner... 684 */ 685 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 686 } 687#endif /* PFIL_HOOKS */ 688 689#ifdef ALTQ 690 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 691 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 692 /* packet dropped by traffic conditioner */ 693 return; 694 } 695#endif 696 697 /* 698 * Process options and, if not destined for us, 699 * ship it on. ip_dooptions returns 1 when an 700 * error was detected (causing an icmp message 701 * to be sent and the original packet to be freed). 702 */ 703 ip_nhops = 0; /* for source routed packets */ 704 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 705 return; 706 707 /* 708 * Enable a consistency check between the destination address 709 * and the arrival interface for a unicast packet (the RFC 1122 710 * strong ES model) if IP forwarding is disabled and the packet 711 * is not locally generated. 712 * 713 * XXX - Checking also should be disabled if the destination 714 * address is ipnat'ed to a different interface. 715 * 716 * XXX - Checking is incompatible with IP aliases added 717 * to the loopback interface instead of the interface where 718 * the packets are received. 719 * 720 * XXX - We need to add a per ifaddr flag for this so that 721 * we get finer grain control. 722 */ 723 checkif = ip_checkinterface && (ipforwarding == 0) && 724 (m->m_pkthdr.rcvif != NULL) && 725 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 726 727 /* 728 * Check our list of addresses, to see if the packet is for us. 729 * 730 * Traditional 4.4BSD did not consult IFF_UP at all. 731 * The behavior here is to treat addresses on !IFF_UP interface 732 * as not mine. 733 */ 734 downmatch = 0; 735 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 736 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 737 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 738 continue; 739 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 740 break; 741 else 742 downmatch++; 743 } 744 } 745 if (ia != NULL) 746 goto ours; 747 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 748 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 749 if (ifa->ifa_addr->sa_family != AF_INET) 750 continue; 751 ia = ifatoia(ifa); 752 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 753 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 754 /* 755 * Look for all-0's host part (old broadcast addr), 756 * either for subnet or net. 757 */ 758 ip->ip_dst.s_addr == ia->ia_subnet || 759 ip->ip_dst.s_addr == ia->ia_net) 760 goto ours; 761 /* 762 * An interface with IP address zero accepts 763 * all packets that arrive on that interface. 764 */ 765 if (in_nullhost(ia->ia_addr.sin_addr)) 766 goto ours; 767 } 768 } 769 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 770 struct in_multi *inm; 771#ifdef MROUTING 772 extern struct socket *ip_mrouter; 773 774 if (ip_mrouter) { 775 /* 776 * If we are acting as a multicast router, all 777 * incoming multicast packets are passed to the 778 * kernel-level multicast forwarding function. 779 * The packet is returned (relatively) intact; if 780 * ip_mforward() returns a non-zero value, the packet 781 * must be discarded, else it may be accepted below. 782 * 783 * (The IP ident field is put in the same byte order 784 * as expected when ip_mforward() is called from 785 * ip_output().) 786 */ 787 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 788 IP_STATINC(IP_STAT_CANTFORWARD); 789 m_freem(m); 790 return; 791 } 792 793 /* 794 * The process-level routing demon needs to receive 795 * all multicast IGMP packets, whether or not this 796 * host belongs to their destination groups. 797 */ 798 if (ip->ip_p == IPPROTO_IGMP) 799 goto ours; 800 IP_STATINC(IP_STAT_CANTFORWARD); 801 } 802#endif 803 /* 804 * See if we belong to the destination multicast group on the 805 * arrival interface. 806 */ 807 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 808 if (inm == NULL) { 809 IP_STATINC(IP_STAT_CANTFORWARD); 810 m_freem(m); 811 return; 812 } 813 goto ours; 814 } 815 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 816 in_nullhost(ip->ip_dst)) 817 goto ours; 818 819 /* 820 * Not for us; forward if possible and desirable. 821 */ 822 if (ipforwarding == 0) { 823 IP_STATINC(IP_STAT_CANTFORWARD); 824 m_freem(m); 825 } else { 826 /* 827 * If ip_dst matched any of my address on !IFF_UP interface, 828 * and there's no IFF_UP interface that matches ip_dst, 829 * send icmp unreach. Forwarding it will result in in-kernel 830 * forwarding loop till TTL goes to 0. 831 */ 832 if (downmatch) { 833 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 834 IP_STATINC(IP_STAT_CANTFORWARD); 835 return; 836 } 837#ifdef IPSEC 838 if (ipsec4_in_reject(m, NULL)) { 839 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 840 goto bad; 841 } 842#endif 843#ifdef FAST_IPSEC 844 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 845 s = splsoftnet(); 846 if (mtag != NULL) { 847 tdbi = (struct tdb_ident *)(mtag + 1); 848 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 849 } else { 850 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 851 IP_FORWARDING, &error); 852 } 853 if (sp == NULL) { /* NB: can happen if error */ 854 splx(s); 855 /*XXX error stat???*/ 856 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/ 857 goto bad; 858 } 859 860 /* 861 * Check security policy against packet attributes. 862 */ 863 error = ipsec_in_reject(sp, m); 864 KEY_FREESP(&sp); 865 splx(s); 866 if (error) { 867 IP_STATINC(IP_STAT_CANTFORWARD); 868 goto bad; 869 } 870 871 /* 872 * Peek at the outbound SP for this packet to determine if 873 * it's a Fast Forward candidate. 874 */ 875 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 876 if (mtag != NULL) 877 m->m_flags &= ~M_CANFASTFWD; 878 else { 879 s = splsoftnet(); 880 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, 881 (IP_FORWARDING | 882 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 883 &error, NULL); 884 if (sp != NULL) { 885 m->m_flags &= ~M_CANFASTFWD; 886 KEY_FREESP(&sp); 887 } 888 splx(s); 889 } 890#endif /* FAST_IPSEC */ 891 892 ip_forward(m, srcrt); 893 } 894 return; 895 896ours: 897 /* 898 * If offset or IP_MF are set, must reassemble. 899 * Otherwise, nothing need be done. 900 * (We could look in the reassembly queue to see 901 * if the packet was previously fragmented, 902 * but it's not worth the time; just let them time out.) 903 */ 904 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 905 uint16_t off; 906 /* 907 * Prevent TCP blind data attacks by not allowing non-initial 908 * fragments to start at less than 68 bytes (minimal fragment 909 * size) and making sure the first fragment is at least 68 910 * bytes. 911 */ 912 off = (ntohs(ip->ip_off) & IP_OFFMASK) << 3; 913 if ((off > 0 ? off + hlen : len) < IP_MINFRAGSIZE - 1) { 914 IP_STATINC(IP_STAT_BADFRAGS); 915 goto bad; 916 } 917 /* 918 * Look for queue of fragments 919 * of this datagram. 920 */ 921 IPQ_LOCK(); 922 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id); 923 LIST_FOREACH(fp, &ipq[hash], ipq_q) { 924 if (ip->ip_id == fp->ipq_id && 925 in_hosteq(ip->ip_src, fp->ipq_src) && 926 in_hosteq(ip->ip_dst, fp->ipq_dst) && 927 ip->ip_p == fp->ipq_p) { 928 /* 929 * Make sure the TOS is matches previous 930 * fragments. 931 */ 932 if (ip->ip_tos != fp->ipq_tos) { 933 IP_STATINC(IP_STAT_BADFRAGS); 934 IPQ_UNLOCK(); 935 goto bad; 936 } 937 goto found; 938 } 939 } 940 fp = 0; 941found: 942 943 /* 944 * Adjust ip_len to not reflect header, 945 * set ipqe_mff if more fragments are expected, 946 * convert offset of this to bytes. 947 */ 948 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 949 mff = (ip->ip_off & htons(IP_MF)) != 0; 950 if (mff) { 951 /* 952 * Make sure that fragments have a data length 953 * that's a non-zero multiple of 8 bytes. 954 */ 955 if (ntohs(ip->ip_len) == 0 || 956 (ntohs(ip->ip_len) & 0x7) != 0) { 957 IP_STATINC(IP_STAT_BADFRAGS); 958 IPQ_UNLOCK(); 959 goto bad; 960 } 961 } 962 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 963 964 /* 965 * If datagram marked as having more fragments 966 * or if this is not the first fragment, 967 * attempt reassembly; if it succeeds, proceed. 968 */ 969 if (mff || ip->ip_off != htons(0)) { 970 IP_STATINC(IP_STAT_FRAGMENTS); 971 s = splvm(); 972 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 973 splx(s); 974 if (ipqe == NULL) { 975 IP_STATINC(IP_STAT_RCVMEMDROP); 976 IPQ_UNLOCK(); 977 goto bad; 978 } 979 ipqe->ipqe_mff = mff; 980 ipqe->ipqe_m = m; 981 ipqe->ipqe_ip = ip; 982 m = ip_reass(ipqe, fp, &ipq[hash]); 983 if (m == 0) { 984 IPQ_UNLOCK(); 985 return; 986 } 987 IP_STATINC(IP_STAT_REASSEMBLED); 988 ip = mtod(m, struct ip *); 989 hlen = ip->ip_hl << 2; 990 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 991 } else 992 if (fp) 993 ip_freef(fp); 994 IPQ_UNLOCK(); 995 } 996 997#if defined(IPSEC) 998 /* 999 * enforce IPsec policy checking if we are seeing last header. 1000 * note that we do not visit this with protocols with pcb layer 1001 * code - like udp/tcp/raw ip. 1002 */ 1003 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 1004 ipsec4_in_reject(m, NULL)) { 1005 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1006 goto bad; 1007 } 1008#endif 1009#ifdef FAST_IPSEC 1010 /* 1011 * enforce IPsec policy checking if we are seeing last header. 1012 * note that we do not visit this with protocols with pcb layer 1013 * code - like udp/tcp/raw ip. 1014 */ 1015 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 1016 /* 1017 * Check if the packet has already had IPsec processing 1018 * done. If so, then just pass it along. This tag gets 1019 * set during AH, ESP, etc. input handling, before the 1020 * packet is returned to the ip input queue for delivery. 1021 */ 1022 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 1023 s = splsoftnet(); 1024 if (mtag != NULL) { 1025 tdbi = (struct tdb_ident *)(mtag + 1); 1026 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 1027 } else { 1028 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1029 IP_FORWARDING, &error); 1030 } 1031 if (sp != NULL) { 1032 /* 1033 * Check security policy against packet attributes. 1034 */ 1035 error = ipsec_in_reject(sp, m); 1036 KEY_FREESP(&sp); 1037 } else { 1038 /* XXX error stat??? */ 1039 error = EINVAL; 1040DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 1041 } 1042 splx(s); 1043 if (error) 1044 goto bad; 1045 } 1046#endif /* FAST_IPSEC */ 1047 1048 /* 1049 * Switch out to protocol's input routine. 1050 */ 1051#if IFA_STATS 1052 if (ia && ip) 1053 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 1054#endif 1055 IP_STATINC(IP_STAT_DELIVERED); 1056 { 1057 int off = hlen, nh = ip->ip_p; 1058 1059 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 1060 return; 1061 } 1062bad: 1063 m_freem(m); 1064 return; 1065 1066badcsum: 1067 IP_STATINC(IP_STAT_BADSUM); 1068 m_freem(m); 1069} 1070 1071/* 1072 * Take incoming datagram fragment and try to 1073 * reassemble it into whole datagram. If a chain for 1074 * reassembly of this datagram already exists, then it 1075 * is given as fp; otherwise have to make a chain. 1076 */ 1077struct mbuf * 1078ip_reass(struct ipqent *ipqe, struct ipq *fp, struct ipqhead *ipqhead) 1079{ 1080 struct mbuf *m = ipqe->ipqe_m; 1081 struct ipqent *nq, *p, *q; 1082 struct ip *ip; 1083 struct mbuf *t; 1084 int hlen = ipqe->ipqe_ip->ip_hl << 2; 1085 int i, next, s; 1086 1087 IPQ_LOCK_CHECK(); 1088 1089 /* 1090 * Presence of header sizes in mbufs 1091 * would confuse code below. 1092 */ 1093 m->m_data += hlen; 1094 m->m_len -= hlen; 1095 1096#ifdef notyet 1097 /* make sure fragment limit is up-to-date */ 1098 CHECK_NMBCLUSTER_PARAMS(); 1099 1100 /* If we have too many fragments, drop the older half. */ 1101 if (ip_nfrags >= ip_maxfrags) 1102 ip_reass_drophalf(void); 1103#endif 1104 1105 /* 1106 * We are about to add a fragment; increment frag count. 1107 */ 1108 ip_nfrags++; 1109 1110 /* 1111 * If first fragment to arrive, create a reassembly queue. 1112 */ 1113 if (fp == 0) { 1114 /* 1115 * Enforce upper bound on number of fragmented packets 1116 * for which we attempt reassembly; 1117 * If maxfrag is 0, never accept fragments. 1118 * If maxfrag is -1, accept all fragments without limitation. 1119 */ 1120 if (ip_maxfragpackets < 0) 1121 ; 1122 else if (ip_nfragpackets >= ip_maxfragpackets) 1123 goto dropfrag; 1124 ip_nfragpackets++; 1125 MALLOC(fp, struct ipq *, sizeof (struct ipq), 1126 M_FTABLE, M_NOWAIT); 1127 if (fp == NULL) 1128 goto dropfrag; 1129 LIST_INSERT_HEAD(ipqhead, fp, ipq_q); 1130 fp->ipq_nfrags = 1; 1131 fp->ipq_ttl = IPFRAGTTL; 1132 fp->ipq_p = ipqe->ipqe_ip->ip_p; 1133 fp->ipq_id = ipqe->ipqe_ip->ip_id; 1134 fp->ipq_tos = ipqe->ipqe_ip->ip_tos; 1135 TAILQ_INIT(&fp->ipq_fragq); 1136 fp->ipq_src = ipqe->ipqe_ip->ip_src; 1137 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 1138 p = NULL; 1139 goto insert; 1140 } else { 1141 fp->ipq_nfrags++; 1142 } 1143 1144 /* 1145 * Find a segment which begins after this one does. 1146 */ 1147 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1148 p = q, q = TAILQ_NEXT(q, ipqe_q)) 1149 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 1150 break; 1151 1152 /* 1153 * If there is a preceding segment, it may provide some of 1154 * our data already. If so, drop the data from the incoming 1155 * segment. If it provides all of our data, drop us. 1156 */ 1157 if (p != NULL) { 1158 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 1159 ntohs(ipqe->ipqe_ip->ip_off); 1160 if (i > 0) { 1161 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 1162 goto dropfrag; 1163 m_adj(ipqe->ipqe_m, i); 1164 ipqe->ipqe_ip->ip_off = 1165 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 1166 ipqe->ipqe_ip->ip_len = 1167 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 1168 } 1169 } 1170 1171 /* 1172 * While we overlap succeeding segments trim them or, 1173 * if they are completely covered, dequeue them. 1174 */ 1175 for (; q != NULL && 1176 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 1177 ntohs(q->ipqe_ip->ip_off); q = nq) { 1178 i = (ntohs(ipqe->ipqe_ip->ip_off) + 1179 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 1180 if (i < ntohs(q->ipqe_ip->ip_len)) { 1181 q->ipqe_ip->ip_len = 1182 htons(ntohs(q->ipqe_ip->ip_len) - i); 1183 q->ipqe_ip->ip_off = 1184 htons(ntohs(q->ipqe_ip->ip_off) + i); 1185 m_adj(q->ipqe_m, i); 1186 break; 1187 } 1188 nq = TAILQ_NEXT(q, ipqe_q); 1189 m_freem(q->ipqe_m); 1190 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1191 s = splvm(); 1192 pool_put(&ipqent_pool, q); 1193 splx(s); 1194 fp->ipq_nfrags--; 1195 ip_nfrags--; 1196 } 1197 1198insert: 1199 /* 1200 * Stick new segment in its place; 1201 * check for complete reassembly. 1202 */ 1203 if (p == NULL) { 1204 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1205 } else { 1206 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1207 } 1208 next = 0; 1209 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1210 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1211 if (ntohs(q->ipqe_ip->ip_off) != next) 1212 return (0); 1213 next += ntohs(q->ipqe_ip->ip_len); 1214 } 1215 if (p->ipqe_mff) 1216 return (0); 1217 1218 /* 1219 * Reassembly is complete. Check for a bogus message size and 1220 * concatenate fragments. 1221 */ 1222 q = TAILQ_FIRST(&fp->ipq_fragq); 1223 ip = q->ipqe_ip; 1224 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1225 IP_STATINC(IP_STAT_TOOLONG); 1226 ip_freef(fp); 1227 return (0); 1228 } 1229 m = q->ipqe_m; 1230 t = m->m_next; 1231 m->m_next = 0; 1232 m_cat(m, t); 1233 nq = TAILQ_NEXT(q, ipqe_q); 1234 s = splvm(); 1235 pool_put(&ipqent_pool, q); 1236 splx(s); 1237 for (q = nq; q != NULL; q = nq) { 1238 t = q->ipqe_m; 1239 nq = TAILQ_NEXT(q, ipqe_q); 1240 s = splvm(); 1241 pool_put(&ipqent_pool, q); 1242 splx(s); 1243 m_cat(m, t); 1244 } 1245 ip_nfrags -= fp->ipq_nfrags; 1246 1247 /* 1248 * Create header for new ip packet by 1249 * modifying header of first packet; 1250 * dequeue and discard fragment reassembly header. 1251 * Make header visible. 1252 */ 1253 ip->ip_len = htons(next); 1254 ip->ip_src = fp->ipq_src; 1255 ip->ip_dst = fp->ipq_dst; 1256 LIST_REMOVE(fp, ipq_q); 1257 FREE(fp, M_FTABLE); 1258 ip_nfragpackets--; 1259 m->m_len += (ip->ip_hl << 2); 1260 m->m_data -= (ip->ip_hl << 2); 1261 /* some debugging cruft by sklower, below, will go away soon */ 1262 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1263 int plen = 0; 1264 for (t = m; t; t = t->m_next) 1265 plen += t->m_len; 1266 m->m_pkthdr.len = plen; 1267 m->m_pkthdr.csum_flags = 0; 1268 } 1269 return (m); 1270 1271dropfrag: 1272 if (fp != 0) 1273 fp->ipq_nfrags--; 1274 ip_nfrags--; 1275 IP_STATINC(IP_STAT_FRAGDROPPED); 1276 m_freem(m); 1277 s = splvm(); 1278 pool_put(&ipqent_pool, ipqe); 1279 splx(s); 1280 return (0); 1281} 1282 1283/* 1284 * Free a fragment reassembly header and all 1285 * associated datagrams. 1286 */ 1287void 1288ip_freef(struct ipq *fp) 1289{ 1290 struct ipqent *q, *p; 1291 u_int nfrags = 0; 1292 int s; 1293 1294 IPQ_LOCK_CHECK(); 1295 1296 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1297 p = TAILQ_NEXT(q, ipqe_q); 1298 m_freem(q->ipqe_m); 1299 nfrags++; 1300 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1301 s = splvm(); 1302 pool_put(&ipqent_pool, q); 1303 splx(s); 1304 } 1305 1306 if (nfrags != fp->ipq_nfrags) 1307 printf("ip_freef: nfrags %d != %d\n", fp->ipq_nfrags, nfrags); 1308 ip_nfrags -= nfrags; 1309 LIST_REMOVE(fp, ipq_q); 1310 FREE(fp, M_FTABLE); 1311 ip_nfragpackets--; 1312} 1313 1314/* 1315 * IP reassembly TTL machinery for multiplicative drop. 1316 */ 1317static u_int fragttl_histo[(IPFRAGTTL+1)]; 1318 1319 1320/* 1321 * Decrement TTL of all reasembly queue entries by `ticks'. 1322 * Count number of distinct fragments (as opposed to partial, fragmented 1323 * datagrams) in the reassembly queue. While we traverse the entire 1324 * reassembly queue, compute and return the median TTL over all fragments. 1325 */ 1326static u_int 1327ip_reass_ttl_decr(u_int ticks) 1328{ 1329 u_int nfrags, median, dropfraction, keepfraction; 1330 struct ipq *fp, *nfp; 1331 int i; 1332 1333 nfrags = 0; 1334 memset(fragttl_histo, 0, sizeof fragttl_histo); 1335 1336 for (i = 0; i < IPREASS_NHASH; i++) { 1337 for (fp = LIST_FIRST(&ipq[i]); fp != NULL; fp = nfp) { 1338 fp->ipq_ttl = ((fp->ipq_ttl <= ticks) ? 1339 0 : fp->ipq_ttl - ticks); 1340 nfp = LIST_NEXT(fp, ipq_q); 1341 if (fp->ipq_ttl == 0) { 1342 IP_STATINC(IP_STAT_FRAGTIMEOUT); 1343 ip_freef(fp); 1344 } else { 1345 nfrags += fp->ipq_nfrags; 1346 fragttl_histo[fp->ipq_ttl] += fp->ipq_nfrags; 1347 } 1348 } 1349 } 1350 1351 KASSERT(ip_nfrags == nfrags); 1352 1353 /* Find median (or other drop fraction) in histogram. */ 1354 dropfraction = (ip_nfrags / 2); 1355 keepfraction = ip_nfrags - dropfraction; 1356 for (i = IPFRAGTTL, median = 0; i >= 0; i--) { 1357 median += fragttl_histo[i]; 1358 if (median >= keepfraction) 1359 break; 1360 } 1361 1362 /* Return TTL of median (or other fraction). */ 1363 return (u_int)i; 1364} 1365 1366void 1367ip_reass_drophalf(void) 1368{ 1369 1370 u_int median_ticks; 1371 /* 1372 * Compute median TTL of all fragments, and count frags 1373 * with that TTL or lower (roughly half of all fragments). 1374 */ 1375 median_ticks = ip_reass_ttl_decr(0); 1376 1377 /* Drop half. */ 1378 median_ticks = ip_reass_ttl_decr(median_ticks); 1379 1380} 1381 1382/* 1383 * IP timer processing; 1384 * if a timer expires on a reassembly 1385 * queue, discard it. 1386 */ 1387void 1388ip_slowtimo(void) 1389{ 1390 static u_int dropscanidx = 0; 1391 u_int i; 1392 u_int median_ttl; 1393 1394 mutex_enter(softnet_lock); 1395 KERNEL_LOCK(1, NULL); 1396 1397 IPQ_LOCK(); 1398 1399 /* Age TTL of all fragments by 1 tick .*/ 1400 median_ttl = ip_reass_ttl_decr(1); 1401 1402 /* make sure fragment limit is up-to-date */ 1403 CHECK_NMBCLUSTER_PARAMS(); 1404 1405 /* If we have too many fragments, drop the older half. */ 1406 if (ip_nfrags > ip_maxfrags) 1407 ip_reass_ttl_decr(median_ttl); 1408 1409 /* 1410 * If we are over the maximum number of fragmented packets 1411 * (due to the limit being lowered), drain off 1412 * enough to get down to the new limit. Start draining 1413 * from the reassembly hashqueue most recently drained. 1414 */ 1415 if (ip_maxfragpackets < 0) 1416 ; 1417 else { 1418 int wrapped = 0; 1419 1420 i = dropscanidx; 1421 while (ip_nfragpackets > ip_maxfragpackets && wrapped == 0) { 1422 while (LIST_FIRST(&ipq[i]) != NULL) 1423 ip_freef(LIST_FIRST(&ipq[i])); 1424 if (++i >= IPREASS_NHASH) { 1425 i = 0; 1426 } 1427 /* 1428 * Dont scan forever even if fragment counters are 1429 * wrong: stop after scanning entire reassembly queue. 1430 */ 1431 if (i == dropscanidx) 1432 wrapped = 1; 1433 } 1434 dropscanidx = i; 1435 } 1436 IPQ_UNLOCK(); 1437 1438 KERNEL_UNLOCK_ONE(NULL); 1439 mutex_exit(softnet_lock); 1440} 1441 1442/* 1443 * Drain off all datagram fragments. Don't acquire softnet_lock as 1444 * can be called from hardware interrupt context. 1445 */ 1446void 1447ip_drain(void) 1448{ 1449 1450 KERNEL_LOCK(1, NULL); 1451 1452 /* 1453 * We may be called from a device's interrupt context. If 1454 * the ipq is already busy, just bail out now. 1455 */ 1456 if (ipq_lock_try() != 0) { 1457 /* 1458 * Drop half the total fragments now. If more mbufs are 1459 * needed, we will be called again soon. 1460 */ 1461 ip_reass_drophalf(); 1462 IPQ_UNLOCK(); 1463 } 1464 1465 KERNEL_UNLOCK_ONE(NULL); 1466} 1467 1468/* 1469 * Do option processing on a datagram, 1470 * possibly discarding it if bad options are encountered, 1471 * or forwarding it if source-routed. 1472 * Returns 1 if packet has been forwarded/freed, 1473 * 0 if the packet should be processed further. 1474 */ 1475int 1476ip_dooptions(struct mbuf *m) 1477{ 1478 struct ip *ip = mtod(m, struct ip *); 1479 u_char *cp, *cp0; 1480 struct ip_timestamp *ipt; 1481 struct in_ifaddr *ia; 1482 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1483 struct in_addr dst; 1484 n_time ntime; 1485 1486 dst = ip->ip_dst; 1487 cp = (u_char *)(ip + 1); 1488 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1489 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1490 opt = cp[IPOPT_OPTVAL]; 1491 if (opt == IPOPT_EOL) 1492 break; 1493 if (opt == IPOPT_NOP) 1494 optlen = 1; 1495 else { 1496 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1497 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1498 goto bad; 1499 } 1500 optlen = cp[IPOPT_OLEN]; 1501 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1502 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1503 goto bad; 1504 } 1505 } 1506 switch (opt) { 1507 1508 default: 1509 break; 1510 1511 /* 1512 * Source routing with record. 1513 * Find interface with current destination address. 1514 * If none on this machine then drop if strictly routed, 1515 * or do nothing if loosely routed. 1516 * Record interface address and bring up next address 1517 * component. If strictly routed make sure next 1518 * address is on directly accessible net. 1519 */ 1520 case IPOPT_LSRR: 1521 case IPOPT_SSRR: 1522 if (ip_allowsrcrt == 0) { 1523 type = ICMP_UNREACH; 1524 code = ICMP_UNREACH_NET_PROHIB; 1525 goto bad; 1526 } 1527 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1528 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1529 goto bad; 1530 } 1531 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1532 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1533 goto bad; 1534 } 1535 ipaddr.sin_addr = ip->ip_dst; 1536 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1537 if (ia == 0) { 1538 if (opt == IPOPT_SSRR) { 1539 type = ICMP_UNREACH; 1540 code = ICMP_UNREACH_SRCFAIL; 1541 goto bad; 1542 } 1543 /* 1544 * Loose routing, and not at next destination 1545 * yet; nothing to do except forward. 1546 */ 1547 break; 1548 } 1549 off--; /* 0 origin */ 1550 if ((off + sizeof(struct in_addr)) > optlen) { 1551 /* 1552 * End of source route. Should be for us. 1553 */ 1554 save_rte(cp, ip->ip_src); 1555 break; 1556 } 1557 /* 1558 * locate outgoing interface 1559 */ 1560 bcopy((void *)(cp + off), (void *)&ipaddr.sin_addr, 1561 sizeof(ipaddr.sin_addr)); 1562 if (opt == IPOPT_SSRR) 1563 ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr))); 1564 else 1565 ia = ip_rtaddr(ipaddr.sin_addr); 1566 if (ia == 0) { 1567 type = ICMP_UNREACH; 1568 code = ICMP_UNREACH_SRCFAIL; 1569 goto bad; 1570 } 1571 ip->ip_dst = ipaddr.sin_addr; 1572 bcopy((void *)&ia->ia_addr.sin_addr, 1573 (void *)(cp + off), sizeof(struct in_addr)); 1574 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1575 /* 1576 * Let ip_intr's mcast routing check handle mcast pkts 1577 */ 1578 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1579 break; 1580 1581 case IPOPT_RR: 1582 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1583 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1584 goto bad; 1585 } 1586 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1587 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1588 goto bad; 1589 } 1590 /* 1591 * If no space remains, ignore. 1592 */ 1593 off--; /* 0 origin */ 1594 if ((off + sizeof(struct in_addr)) > optlen) 1595 break; 1596 bcopy((void *)(&ip->ip_dst), (void *)&ipaddr.sin_addr, 1597 sizeof(ipaddr.sin_addr)); 1598 /* 1599 * locate outgoing interface; if we're the destination, 1600 * use the incoming interface (should be same). 1601 */ 1602 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1603 == NULL && 1604 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1605 type = ICMP_UNREACH; 1606 code = ICMP_UNREACH_HOST; 1607 goto bad; 1608 } 1609 bcopy((void *)&ia->ia_addr.sin_addr, 1610 (void *)(cp + off), sizeof(struct in_addr)); 1611 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1612 break; 1613 1614 case IPOPT_TS: 1615 code = cp - (u_char *)ip; 1616 ipt = (struct ip_timestamp *)cp; 1617 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1618 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1619 goto bad; 1620 } 1621 if (ipt->ipt_ptr < 5) { 1622 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1623 goto bad; 1624 } 1625 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1626 if (++ipt->ipt_oflw == 0) { 1627 code = (u_char *)&ipt->ipt_ptr - 1628 (u_char *)ip; 1629 goto bad; 1630 } 1631 break; 1632 } 1633 cp0 = (cp + ipt->ipt_ptr - 1); 1634 switch (ipt->ipt_flg) { 1635 1636 case IPOPT_TS_TSONLY: 1637 break; 1638 1639 case IPOPT_TS_TSANDADDR: 1640 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1641 sizeof(struct in_addr) > ipt->ipt_len) { 1642 code = (u_char *)&ipt->ipt_ptr - 1643 (u_char *)ip; 1644 goto bad; 1645 } 1646 ipaddr.sin_addr = dst; 1647 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1648 m->m_pkthdr.rcvif)); 1649 if (ia == 0) 1650 continue; 1651 bcopy(&ia->ia_addr.sin_addr, 1652 cp0, sizeof(struct in_addr)); 1653 ipt->ipt_ptr += sizeof(struct in_addr); 1654 break; 1655 1656 case IPOPT_TS_PRESPEC: 1657 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1658 sizeof(struct in_addr) > ipt->ipt_len) { 1659 code = (u_char *)&ipt->ipt_ptr - 1660 (u_char *)ip; 1661 goto bad; 1662 } 1663 bcopy(cp0, &ipaddr.sin_addr, 1664 sizeof(struct in_addr)); 1665 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1666 == NULL) 1667 continue; 1668 ipt->ipt_ptr += sizeof(struct in_addr); 1669 break; 1670 1671 default: 1672 /* XXX can't take &ipt->ipt_flg */ 1673 code = (u_char *)&ipt->ipt_ptr - 1674 (u_char *)ip + 1; 1675 goto bad; 1676 } 1677 ntime = iptime(); 1678 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1679 memmove((char *)cp + ipt->ipt_ptr - 1, cp0, 1680 sizeof(n_time)); 1681 ipt->ipt_ptr += sizeof(n_time); 1682 } 1683 } 1684 if (forward) { 1685 if (ip_forwsrcrt == 0) { 1686 type = ICMP_UNREACH; 1687 code = ICMP_UNREACH_SRCFAIL; 1688 goto bad; 1689 } 1690 ip_forward(m, 1); 1691 return (1); 1692 } 1693 return (0); 1694bad: 1695 icmp_error(m, type, code, 0, 0); 1696 IP_STATINC(IP_STAT_BADOPTIONS); 1697 return (1); 1698} 1699 1700/* 1701 * Given address of next destination (final or next hop), 1702 * return internet address info of interface to be used to get there. 1703 */ 1704struct in_ifaddr * 1705ip_rtaddr(struct in_addr dst) 1706{ 1707 struct rtentry *rt; 1708 union { 1709 struct sockaddr dst; 1710 struct sockaddr_in dst4; 1711 } u; 1712 1713 sockaddr_in_init(&u.dst4, &dst, 0); 1714 1715 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) 1716 return NULL; 1717 1718 return ifatoia(rt->rt_ifa); 1719} 1720 1721/* 1722 * Save incoming source route for use in replies, 1723 * to be picked up later by ip_srcroute if the receiver is interested. 1724 */ 1725void 1726save_rte(u_char *option, struct in_addr dst) 1727{ 1728 unsigned olen; 1729 1730 olen = option[IPOPT_OLEN]; 1731#ifdef DIAGNOSTIC 1732 if (ipprintfs) 1733 printf("save_rte: olen %d\n", olen); 1734#endif /* 0 */ 1735 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1736 return; 1737 bcopy((void *)option, (void *)ip_srcrt.srcopt, olen); 1738 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1739 ip_srcrt.dst = dst; 1740} 1741 1742/* 1743 * Retrieve incoming source route for use in replies, 1744 * in the same form used by setsockopt. 1745 * The first hop is placed before the options, will be removed later. 1746 */ 1747struct mbuf * 1748ip_srcroute(void) 1749{ 1750 struct in_addr *p, *q; 1751 struct mbuf *m; 1752 1753 if (ip_nhops == 0) 1754 return NULL; 1755 m = m_get(M_DONTWAIT, MT_SOOPTS); 1756 if (m == 0) 1757 return NULL; 1758 1759 MCLAIM(m, &inetdomain.dom_mowner); 1760#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1761 1762 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1763 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1764 OPTSIZ; 1765#ifdef DIAGNOSTIC 1766 if (ipprintfs) 1767 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1768#endif 1769 1770 /* 1771 * First save first hop for return route 1772 */ 1773 p = &ip_srcrt.route[ip_nhops - 1]; 1774 *(mtod(m, struct in_addr *)) = *p--; 1775#ifdef DIAGNOSTIC 1776 if (ipprintfs) 1777 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1778#endif 1779 1780 /* 1781 * Copy option fields and padding (nop) to mbuf. 1782 */ 1783 ip_srcrt.nop = IPOPT_NOP; 1784 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1785 memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop, 1786 OPTSIZ); 1787 q = (struct in_addr *)(mtod(m, char *) + 1788 sizeof(struct in_addr) + OPTSIZ); 1789#undef OPTSIZ 1790 /* 1791 * Record return path as an IP source route, 1792 * reversing the path (pointers are now aligned). 1793 */ 1794 while (p >= ip_srcrt.route) { 1795#ifdef DIAGNOSTIC 1796 if (ipprintfs) 1797 printf(" %x", ntohl(q->s_addr)); 1798#endif 1799 *q++ = *p--; 1800 } 1801 /* 1802 * Last hop goes to final destination. 1803 */ 1804 *q = ip_srcrt.dst; 1805#ifdef DIAGNOSTIC 1806 if (ipprintfs) 1807 printf(" %x\n", ntohl(q->s_addr)); 1808#endif 1809 return (m); 1810} 1811 1812const int inetctlerrmap[PRC_NCMDS] = { 1813 [PRC_MSGSIZE] = EMSGSIZE, 1814 [PRC_HOSTDEAD] = EHOSTDOWN, 1815 [PRC_HOSTUNREACH] = EHOSTUNREACH, 1816 [PRC_UNREACH_NET] = EHOSTUNREACH, 1817 [PRC_UNREACH_HOST] = EHOSTUNREACH, 1818 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED, 1819 [PRC_UNREACH_PORT] = ECONNREFUSED, 1820 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH, 1821 [PRC_PARAMPROB] = ENOPROTOOPT, 1822}; 1823 1824/* 1825 * Forward a packet. If some error occurs return the sender 1826 * an icmp packet. Note we can't always generate a meaningful 1827 * icmp message because icmp doesn't have a large enough repertoire 1828 * of codes and types. 1829 * 1830 * If not forwarding, just drop the packet. This could be confusing 1831 * if ipforwarding was zero but some routing protocol was advancing 1832 * us as a gateway to somewhere. However, we must let the routing 1833 * protocol deal with that. 1834 * 1835 * The srcrt parameter indicates whether the packet is being forwarded 1836 * via a source route. 1837 */ 1838void 1839ip_forward(struct mbuf *m, int srcrt) 1840{ 1841 struct ip *ip = mtod(m, struct ip *); 1842 struct rtentry *rt; 1843 int error, type = 0, code = 0, destmtu = 0; 1844 struct mbuf *mcopy; 1845 n_long dest; 1846 union { 1847 struct sockaddr dst; 1848 struct sockaddr_in dst4; 1849 } u; 1850 1851 /* 1852 * We are now in the output path. 1853 */ 1854 MCLAIM(m, &ip_tx_mowner); 1855 1856 /* 1857 * Clear any in-bound checksum flags for this packet. 1858 */ 1859 m->m_pkthdr.csum_flags = 0; 1860 1861 dest = 0; 1862#ifdef DIAGNOSTIC 1863 if (ipprintfs) { 1864 printf("forward: src %s ", inet_ntoa(ip->ip_src)); 1865 printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl); 1866 } 1867#endif 1868 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1869 IP_STATINC(IP_STAT_CANTFORWARD); 1870 m_freem(m); 1871 return; 1872 } 1873 if (ip->ip_ttl <= IPTTLDEC) { 1874 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1875 return; 1876 } 1877 1878 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0); 1879 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) { 1880 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0); 1881 return; 1882 } 1883 1884 /* 1885 * Save at most 68 bytes of the packet in case 1886 * we need to generate an ICMP message to the src. 1887 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1888 */ 1889 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1890 if (mcopy) 1891 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1892 1893 ip->ip_ttl -= IPTTLDEC; 1894 1895 /* 1896 * If forwarding packet using same interface that it came in on, 1897 * perhaps should send a redirect to sender to shortcut a hop. 1898 * Only send redirect if source is sending directly to us, 1899 * and if packet was not source routed (or has any options). 1900 * Also, don't send redirect if forwarding using a default route 1901 * or a route modified by a redirect. 1902 */ 1903 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1904 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1905 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) && 1906 ipsendredirects && !srcrt) { 1907 if (rt->rt_ifa && 1908 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1909 ifatoia(rt->rt_ifa)->ia_subnet) { 1910 if (rt->rt_flags & RTF_GATEWAY) 1911 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1912 else 1913 dest = ip->ip_dst.s_addr; 1914 /* 1915 * Router requirements says to only send host 1916 * redirects. 1917 */ 1918 type = ICMP_REDIRECT; 1919 code = ICMP_REDIRECT_HOST; 1920#ifdef DIAGNOSTIC 1921 if (ipprintfs) 1922 printf("redirect (%d) to %x\n", code, 1923 (u_int32_t)dest); 1924#endif 1925 } 1926 } 1927 1928 error = ip_output(m, NULL, &ipforward_rt, 1929 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1930 (struct ip_moptions *)NULL, (struct socket *)NULL); 1931 1932 if (error) 1933 IP_STATINC(IP_STAT_CANTFORWARD); 1934 else { 1935 uint64_t *ips = IP_STAT_GETREF(); 1936 ips[IP_STAT_FORWARD]++; 1937 if (type) { 1938 ips[IP_STAT_REDIRECTSENT]++; 1939 IP_STAT_PUTREF(); 1940 } else { 1941 IP_STAT_PUTREF(); 1942 if (mcopy) { 1943#ifdef GATEWAY 1944 if (mcopy->m_flags & M_CANFASTFWD) 1945 ipflow_create(&ipforward_rt, mcopy); 1946#endif 1947 m_freem(mcopy); 1948 } 1949 return; 1950 } 1951 } 1952 if (mcopy == NULL) 1953 return; 1954 1955 switch (error) { 1956 1957 case 0: /* forwarded, but need redirect */ 1958 /* type, code set above */ 1959 break; 1960 1961 case ENETUNREACH: /* shouldn't happen, checked above */ 1962 case EHOSTUNREACH: 1963 case ENETDOWN: 1964 case EHOSTDOWN: 1965 default: 1966 type = ICMP_UNREACH; 1967 code = ICMP_UNREACH_HOST; 1968 break; 1969 1970 case EMSGSIZE: 1971 type = ICMP_UNREACH; 1972 code = ICMP_UNREACH_NEEDFRAG; 1973 1974 if ((rt = rtcache_validate(&ipforward_rt)) != NULL) 1975 destmtu = rt->rt_ifp->if_mtu; 1976 1977#if defined(IPSEC) || defined(FAST_IPSEC) 1978 { 1979 /* 1980 * If the packet is routed over IPsec tunnel, tell the 1981 * originator the tunnel MTU. 1982 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1983 * XXX quickhack!!! 1984 */ 1985 1986 struct secpolicy *sp; 1987 int ipsecerror; 1988 size_t ipsechdr; 1989 struct route *ro; 1990 1991 sp = ipsec4_getpolicybyaddr(mcopy, 1992 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1993 &ipsecerror); 1994 1995 if (sp != NULL) { 1996 /* count IPsec header size */ 1997 ipsechdr = ipsec4_hdrsiz(mcopy, 1998 IPSEC_DIR_OUTBOUND, NULL); 1999 2000 /* 2001 * find the correct route for outer IPv4 2002 * header, compute tunnel MTU. 2003 */ 2004 2005 if (sp->req != NULL 2006 && sp->req->sav != NULL 2007 && sp->req->sav->sah != NULL) { 2008 ro = &sp->req->sav->sah->sa_route; 2009 rt = rtcache_validate(ro); 2010 if (rt && rt->rt_ifp) { 2011 destmtu = 2012 rt->rt_rmx.rmx_mtu ? 2013 rt->rt_rmx.rmx_mtu : 2014 rt->rt_ifp->if_mtu; 2015 destmtu -= ipsechdr; 2016 } 2017 } 2018 2019#ifdef IPSEC 2020 key_freesp(sp); 2021#else 2022 KEY_FREESP(&sp); 2023#endif 2024 } 2025 } 2026#endif /*defined(IPSEC) || defined(FAST_IPSEC)*/ 2027 IP_STATINC(IP_STAT_CANTFRAG); 2028 break; 2029 2030 case ENOBUFS: 2031#if 1 2032 /* 2033 * a router should not generate ICMP_SOURCEQUENCH as 2034 * required in RFC1812 Requirements for IP Version 4 Routers. 2035 * source quench could be a big problem under DoS attacks, 2036 * or if the underlying interface is rate-limited. 2037 */ 2038 if (mcopy) 2039 m_freem(mcopy); 2040 return; 2041#else 2042 type = ICMP_SOURCEQUENCH; 2043 code = 0; 2044 break; 2045#endif 2046 } 2047 icmp_error(mcopy, type, code, dest, destmtu); 2048} 2049 2050void 2051ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 2052 struct mbuf *m) 2053{ 2054 2055 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 2056 struct timeval tv; 2057 2058 microtime(&tv); 2059 *mp = sbcreatecontrol((void *) &tv, sizeof(tv), 2060 SCM_TIMESTAMP, SOL_SOCKET); 2061 if (*mp) 2062 mp = &(*mp)->m_next; 2063 } 2064 if (inp->inp_flags & INP_RECVDSTADDR) { 2065 *mp = sbcreatecontrol((void *) &ip->ip_dst, 2066 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 2067 if (*mp) 2068 mp = &(*mp)->m_next; 2069 } 2070#ifdef notyet 2071 /* 2072 * XXX 2073 * Moving these out of udp_input() made them even more broken 2074 * than they already were. 2075 * - fenner@parc.xerox.com 2076 */ 2077 /* options were tossed already */ 2078 if (inp->inp_flags & INP_RECVOPTS) { 2079 *mp = sbcreatecontrol((void *) opts_deleted_above, 2080 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 2081 if (*mp) 2082 mp = &(*mp)->m_next; 2083 } 2084 /* ip_srcroute doesn't do what we want here, need to fix */ 2085 if (inp->inp_flags & INP_RECVRETOPTS) { 2086 *mp = sbcreatecontrol((void *) ip_srcroute(), 2087 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 2088 if (*mp) 2089 mp = &(*mp)->m_next; 2090 } 2091#endif 2092 if (inp->inp_flags & INP_RECVIF) { 2093 struct sockaddr_dl sdl; 2094 2095 sockaddr_dl_init(&sdl, sizeof(sdl), 2096 (m->m_pkthdr.rcvif != NULL) 2097 ? m->m_pkthdr.rcvif->if_index 2098 : 0, 2099 0, NULL, 0, NULL, 0); 2100 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP); 2101 if (*mp) 2102 mp = &(*mp)->m_next; 2103 } 2104} 2105 2106/* 2107 * sysctl helper routine for net.inet.ip.forwsrcrt. 2108 */ 2109static int 2110sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS) 2111{ 2112 int error, tmp; 2113 struct sysctlnode node; 2114 2115 node = *rnode; 2116 tmp = ip_forwsrcrt; 2117 node.sysctl_data = &tmp; 2118 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2119 if (error || newp == NULL) 2120 return (error); 2121 2122 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT, 2123 0, NULL, NULL, NULL)) 2124 return (EPERM); 2125 2126 ip_forwsrcrt = tmp; 2127 2128 return (0); 2129} 2130 2131/* 2132 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the 2133 * range of the new value and tweaks timers if it changes. 2134 */ 2135static int 2136sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS) 2137{ 2138 int error, tmp; 2139 struct sysctlnode node; 2140 2141 node = *rnode; 2142 tmp = ip_mtudisc_timeout; 2143 node.sysctl_data = &tmp; 2144 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2145 if (error || newp == NULL) 2146 return (error); 2147 if (tmp < 0) 2148 return (EINVAL); 2149 2150 mutex_enter(softnet_lock); 2151 2152 ip_mtudisc_timeout = tmp; 2153 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 2154 2155 mutex_exit(softnet_lock); 2156 2157 return (0); 2158} 2159 2160#ifdef GATEWAY 2161/* 2162 * sysctl helper routine for net.inet.ip.maxflows. 2163 */ 2164static int 2165sysctl_net_inet_ip_maxflows(SYSCTLFN_ARGS) 2166{ 2167 int error; 2168 2169 error = sysctl_lookup(SYSCTLFN_CALL(rnode)); 2170 if (error || newp == NULL) 2171 return (error); 2172 2173 mutex_enter(softnet_lock); 2174 KERNEL_LOCK(1, NULL); 2175 2176 ipflow_prune(); 2177 2178 KERNEL_UNLOCK_ONE(NULL); 2179 mutex_exit(softnet_lock); 2180 2181 return (0); 2182} 2183 2184static int 2185sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS) 2186{ 2187 int error, tmp; 2188 struct sysctlnode node; 2189 2190 node = *rnode; 2191 tmp = ip_hashsize; 2192 node.sysctl_data = &tmp; 2193 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2194 if (error || newp == NULL) 2195 return (error); 2196 2197 if ((tmp & (tmp - 1)) == 0 && tmp != 0) { 2198 /* 2199 * Can only fail due to malloc() 2200 */ 2201 mutex_enter(softnet_lock); 2202 KERNEL_LOCK(1, NULL); 2203 2204 error = ipflow_invalidate_all(tmp); 2205 2206 KERNEL_UNLOCK_ONE(NULL); 2207 mutex_exit(softnet_lock); 2208 2209 } else { 2210 /* 2211 * EINVAL if not a power of 2 2212 */ 2213 error = EINVAL; 2214 } 2215 2216 return error; 2217} 2218#endif /* GATEWAY */ 2219 2220static int 2221sysctl_net_inet_ip_stats(SYSCTLFN_ARGS) 2222{ 2223 2224 return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS)); 2225} 2226 2227SYSCTL_SETUP(sysctl_net_inet_ip_setup, "sysctl net.inet.ip subtree setup") 2228{ 2229 extern int subnetsarelocal, hostzeroisbroadcast; 2230 2231 sysctl_createv(clog, 0, NULL, NULL, 2232 CTLFLAG_PERMANENT, 2233 CTLTYPE_NODE, "net", NULL, 2234 NULL, 0, NULL, 0, 2235 CTL_NET, CTL_EOL); 2236 sysctl_createv(clog, 0, NULL, NULL, 2237 CTLFLAG_PERMANENT, 2238 CTLTYPE_NODE, "inet", 2239 SYSCTL_DESCR("PF_INET related settings"), 2240 NULL, 0, NULL, 0, 2241 CTL_NET, PF_INET, CTL_EOL); 2242 sysctl_createv(clog, 0, NULL, NULL, 2243 CTLFLAG_PERMANENT, 2244 CTLTYPE_NODE, "ip", 2245 SYSCTL_DESCR("IPv4 related settings"), 2246 NULL, 0, NULL, 0, 2247 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL); 2248 2249 sysctl_createv(clog, 0, NULL, NULL, 2250 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2251 CTLTYPE_INT, "forwarding", 2252 SYSCTL_DESCR("Enable forwarding of INET datagrams"), 2253 NULL, 0, &ipforwarding, 0, 2254 CTL_NET, PF_INET, IPPROTO_IP, 2255 IPCTL_FORWARDING, CTL_EOL); 2256 sysctl_createv(clog, 0, NULL, NULL, 2257 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2258 CTLTYPE_INT, "redirect", 2259 SYSCTL_DESCR("Enable sending of ICMP redirect messages"), 2260 NULL, 0, &ipsendredirects, 0, 2261 CTL_NET, PF_INET, IPPROTO_IP, 2262 IPCTL_SENDREDIRECTS, CTL_EOL); 2263 sysctl_createv(clog, 0, NULL, NULL, 2264 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2265 CTLTYPE_INT, "ttl", 2266 SYSCTL_DESCR("Default TTL for an INET datagram"), 2267 NULL, 0, &ip_defttl, 0, 2268 CTL_NET, PF_INET, IPPROTO_IP, 2269 IPCTL_DEFTTL, CTL_EOL); 2270#ifdef IPCTL_DEFMTU 2271 sysctl_createv(clog, 0, NULL, NULL, 2272 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */, 2273 CTLTYPE_INT, "mtu", 2274 SYSCTL_DESCR("Default MTA for an INET route"), 2275 NULL, 0, &ip_mtu, 0, 2276 CTL_NET, PF_INET, IPPROTO_IP, 2277 IPCTL_DEFMTU, CTL_EOL); 2278#endif /* IPCTL_DEFMTU */ 2279 sysctl_createv(clog, 0, NULL, NULL, 2280 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2281 CTLTYPE_INT, "forwsrcrt", 2282 SYSCTL_DESCR("Enable forwarding of source-routed " 2283 "datagrams"), 2284 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0, 2285 CTL_NET, PF_INET, IPPROTO_IP, 2286 IPCTL_FORWSRCRT, CTL_EOL); 2287 sysctl_createv(clog, 0, NULL, NULL, 2288 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2289 CTLTYPE_INT, "directed-broadcast", 2290 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"), 2291 NULL, 0, &ip_directedbcast, 0, 2292 CTL_NET, PF_INET, IPPROTO_IP, 2293 IPCTL_DIRECTEDBCAST, CTL_EOL); 2294 sysctl_createv(clog, 0, NULL, NULL, 2295 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2296 CTLTYPE_INT, "allowsrcrt", 2297 SYSCTL_DESCR("Accept source-routed datagrams"), 2298 NULL, 0, &ip_allowsrcrt, 0, 2299 CTL_NET, PF_INET, IPPROTO_IP, 2300 IPCTL_ALLOWSRCRT, CTL_EOL); 2301 sysctl_createv(clog, 0, NULL, NULL, 2302 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2303 CTLTYPE_INT, "subnetsarelocal", 2304 SYSCTL_DESCR("Whether logical subnets are considered " 2305 "local"), 2306 NULL, 0, &subnetsarelocal, 0, 2307 CTL_NET, PF_INET, IPPROTO_IP, 2308 IPCTL_SUBNETSARELOCAL, CTL_EOL); 2309 sysctl_createv(clog, 0, NULL, NULL, 2310 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2311 CTLTYPE_INT, "mtudisc", 2312 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"), 2313 NULL, 0, &ip_mtudisc, 0, 2314 CTL_NET, PF_INET, IPPROTO_IP, 2315 IPCTL_MTUDISC, CTL_EOL); 2316 sysctl_createv(clog, 0, NULL, NULL, 2317 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2318 CTLTYPE_INT, "anonportmin", 2319 SYSCTL_DESCR("Lowest ephemeral port number to assign"), 2320 sysctl_net_inet_ip_ports, 0, &anonportmin, 0, 2321 CTL_NET, PF_INET, IPPROTO_IP, 2322 IPCTL_ANONPORTMIN, CTL_EOL); 2323 sysctl_createv(clog, 0, NULL, NULL, 2324 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2325 CTLTYPE_INT, "anonportmax", 2326 SYSCTL_DESCR("Highest ephemeral port number to assign"), 2327 sysctl_net_inet_ip_ports, 0, &anonportmax, 0, 2328 CTL_NET, PF_INET, IPPROTO_IP, 2329 IPCTL_ANONPORTMAX, CTL_EOL); 2330 sysctl_createv(clog, 0, NULL, NULL, 2331 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2332 CTLTYPE_INT, "mtudisctimeout", 2333 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"), 2334 sysctl_net_inet_ip_pmtudto, 0, &ip_mtudisc_timeout, 0, 2335 CTL_NET, PF_INET, IPPROTO_IP, 2336 IPCTL_MTUDISCTIMEOUT, CTL_EOL); 2337#ifdef GATEWAY 2338 sysctl_createv(clog, 0, NULL, NULL, 2339 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2340 CTLTYPE_INT, "maxflows", 2341 SYSCTL_DESCR("Number of flows for fast forwarding"), 2342 sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0, 2343 CTL_NET, PF_INET, IPPROTO_IP, 2344 IPCTL_MAXFLOWS, CTL_EOL); 2345 sysctl_createv(clog, 0, NULL, NULL, 2346 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2347 CTLTYPE_INT, "hashsize", 2348 SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"), 2349 sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0, 2350 CTL_NET, PF_INET, IPPROTO_IP, 2351 CTL_CREATE, CTL_EOL); 2352#endif /* GATEWAY */ 2353 sysctl_createv(clog, 0, NULL, NULL, 2354 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2355 CTLTYPE_INT, "hostzerobroadcast", 2356 SYSCTL_DESCR("All zeroes address is broadcast address"), 2357 NULL, 0, &hostzeroisbroadcast, 0, 2358 CTL_NET, PF_INET, IPPROTO_IP, 2359 IPCTL_HOSTZEROBROADCAST, CTL_EOL); 2360#if NGIF > 0 2361 sysctl_createv(clog, 0, NULL, NULL, 2362 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2363 CTLTYPE_INT, "gifttl", 2364 SYSCTL_DESCR("Default TTL for a gif tunnel datagram"), 2365 NULL, 0, &ip_gif_ttl, 0, 2366 CTL_NET, PF_INET, IPPROTO_IP, 2367 IPCTL_GIF_TTL, CTL_EOL); 2368#endif /* NGIF */ 2369#ifndef IPNOPRIVPORTS 2370 sysctl_createv(clog, 0, NULL, NULL, 2371 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2372 CTLTYPE_INT, "lowportmin", 2373 SYSCTL_DESCR("Lowest privileged ephemeral port number " 2374 "to assign"), 2375 sysctl_net_inet_ip_ports, 0, &lowportmin, 0, 2376 CTL_NET, PF_INET, IPPROTO_IP, 2377 IPCTL_LOWPORTMIN, CTL_EOL); 2378 sysctl_createv(clog, 0, NULL, NULL, 2379 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2380 CTLTYPE_INT, "lowportmax", 2381 SYSCTL_DESCR("Highest privileged ephemeral port number " 2382 "to assign"), 2383 sysctl_net_inet_ip_ports, 0, &lowportmax, 0, 2384 CTL_NET, PF_INET, IPPROTO_IP, 2385 IPCTL_LOWPORTMAX, CTL_EOL); 2386#endif /* IPNOPRIVPORTS */ 2387 sysctl_createv(clog, 0, NULL, NULL, 2388 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2389 CTLTYPE_INT, "maxfragpackets", 2390 SYSCTL_DESCR("Maximum number of fragments to retain for " 2391 "possible reassembly"), 2392 NULL, 0, &ip_maxfragpackets, 0, 2393 CTL_NET, PF_INET, IPPROTO_IP, 2394 IPCTL_MAXFRAGPACKETS, CTL_EOL); 2395#if NGRE > 0 2396 sysctl_createv(clog, 0, NULL, NULL, 2397 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2398 CTLTYPE_INT, "grettl", 2399 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"), 2400 NULL, 0, &ip_gre_ttl, 0, 2401 CTL_NET, PF_INET, IPPROTO_IP, 2402 IPCTL_GRE_TTL, CTL_EOL); 2403#endif /* NGRE */ 2404 sysctl_createv(clog, 0, NULL, NULL, 2405 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2406 CTLTYPE_INT, "checkinterface", 2407 SYSCTL_DESCR("Enable receive side of Strong ES model " 2408 "from RFC1122"), 2409 NULL, 0, &ip_checkinterface, 0, 2410 CTL_NET, PF_INET, IPPROTO_IP, 2411 IPCTL_CHECKINTERFACE, CTL_EOL); 2412 sysctl_createv(clog, 0, NULL, NULL, 2413 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2414 CTLTYPE_INT, "random_id", 2415 SYSCTL_DESCR("Assign random ip_id values"), 2416 NULL, 0, &ip_do_randomid, 0, 2417 CTL_NET, PF_INET, IPPROTO_IP, 2418 IPCTL_RANDOMID, CTL_EOL); 2419 sysctl_createv(clog, 0, NULL, NULL, 2420 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2421 CTLTYPE_INT, "do_loopback_cksum", 2422 SYSCTL_DESCR("Perform IP checksum on loopback"), 2423 NULL, 0, &ip_do_loopback_cksum, 0, 2424 CTL_NET, PF_INET, IPPROTO_IP, 2425 IPCTL_LOOPBACKCKSUM, CTL_EOL); 2426 sysctl_createv(clog, 0, NULL, NULL, 2427 CTLFLAG_PERMANENT, 2428 CTLTYPE_STRUCT, "stats", 2429 SYSCTL_DESCR("IP statistics"), 2430 sysctl_net_inet_ip_stats, 0, NULL, 0, 2431 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS, 2432 CTL_EOL); 2433} 2434 2435void 2436ip_statinc(u_int stat) 2437{ 2438 2439 KASSERT(stat < IP_NSTATS); 2440 IP_STATINC(stat); 2441} 2442