ip_input.c revision 1.266
1/* $NetBSD: ip_input.c,v 1.266 2008/04/12 05:58:22 thorpej 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. Neither the name of the University nor the names of its contributors 82 * may be used to endorse or promote products derived from this software 83 * without specific prior written permission. 84 * 85 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 86 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 87 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 88 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 89 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 90 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 91 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 92 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 93 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 94 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 95 * SUCH DAMAGE. 96 * 97 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 98 */ 99 100#include <sys/cdefs.h> 101__KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.266 2008/04/12 05:58:22 thorpej Exp $"); 102 103#include "opt_inet.h" 104#include "opt_gateway.h" 105#include "opt_pfil_hooks.h" 106#include "opt_ipsec.h" 107#include "opt_mrouting.h" 108#include "opt_mbuftrace.h" 109#include "opt_inet_csum.h" 110 111#include <sys/param.h> 112#include <sys/systm.h> 113#include <sys/malloc.h> 114#include <sys/mbuf.h> 115#include <sys/domain.h> 116#include <sys/protosw.h> 117#include <sys/socket.h> 118#include <sys/socketvar.h> 119#include <sys/errno.h> 120#include <sys/time.h> 121#include <sys/kernel.h> 122#include <sys/pool.h> 123#include <sys/sysctl.h> 124#include <sys/kauth.h> 125 126#include <net/if.h> 127#include <net/if_dl.h> 128#include <net/route.h> 129#include <net/pfil.h> 130 131#include <netinet/in.h> 132#include <netinet/in_systm.h> 133#include <netinet/ip.h> 134#include <netinet/in_pcb.h> 135#include <netinet/in_proto.h> 136#include <netinet/in_var.h> 137#include <netinet/ip_var.h> 138#include <netinet/ip_private.h> 139#include <netinet/ip_icmp.h> 140/* just for gif_ttl */ 141#include <netinet/in_gif.h> 142#include "gif.h" 143#include <net/if_gre.h> 144#include "gre.h" 145 146#ifdef MROUTING 147#include <netinet/ip_mroute.h> 148#endif 149 150#ifdef IPSEC 151#include <netinet6/ipsec.h> 152#include <netkey/key.h> 153#endif 154#ifdef FAST_IPSEC 155#include <netipsec/ipsec.h> 156#include <netipsec/key.h> 157#endif /* FAST_IPSEC*/ 158 159#ifndef IPFORWARDING 160#ifdef GATEWAY 161#define IPFORWARDING 1 /* forward IP packets not for us */ 162#else /* GATEWAY */ 163#define IPFORWARDING 0 /* don't forward IP packets not for us */ 164#endif /* GATEWAY */ 165#endif /* IPFORWARDING */ 166#ifndef IPSENDREDIRECTS 167#define IPSENDREDIRECTS 1 168#endif 169#ifndef IPFORWSRCRT 170#define IPFORWSRCRT 1 /* forward source-routed packets */ 171#endif 172#ifndef IPALLOWSRCRT 173#define IPALLOWSRCRT 1 /* allow source-routed packets */ 174#endif 175#ifndef IPMTUDISC 176#define IPMTUDISC 1 177#endif 178#ifndef IPMTUDISCTIMEOUT 179#define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 180#endif 181 182/* 183 * Note: DIRECTED_BROADCAST is handled this way so that previous 184 * configuration using this option will Just Work. 185 */ 186#ifndef IPDIRECTEDBCAST 187#ifdef DIRECTED_BROADCAST 188#define IPDIRECTEDBCAST 1 189#else 190#define IPDIRECTEDBCAST 0 191#endif /* DIRECTED_BROADCAST */ 192#endif /* IPDIRECTEDBCAST */ 193int ipforwarding = IPFORWARDING; 194int ipsendredirects = IPSENDREDIRECTS; 195int ip_defttl = IPDEFTTL; 196int ip_forwsrcrt = IPFORWSRCRT; 197int ip_directedbcast = IPDIRECTEDBCAST; 198int ip_allowsrcrt = IPALLOWSRCRT; 199int ip_mtudisc = IPMTUDISC; 200int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 201#ifdef DIAGNOSTIC 202int ipprintfs = 0; 203#endif 204 205int ip_do_randomid = 0; 206 207/* 208 * XXX - Setting ip_checkinterface mostly implements the receive side of 209 * the Strong ES model described in RFC 1122, but since the routing table 210 * and transmit implementation do not implement the Strong ES model, 211 * setting this to 1 results in an odd hybrid. 212 * 213 * XXX - ip_checkinterface currently must be disabled if you use ipnat 214 * to translate the destination address to another local interface. 215 * 216 * XXX - ip_checkinterface must be disabled if you add IP aliases 217 * to the loopback interface instead of the interface where the 218 * packets for those addresses are received. 219 */ 220int ip_checkinterface = 0; 221 222 223struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 224 225int ipqmaxlen = IFQ_MAXLEN; 226u_long in_ifaddrhash; /* size of hash table - 1 */ 227int in_ifaddrentries; /* total number of addrs */ 228struct in_ifaddrhead in_ifaddrhead; 229struct in_ifaddrhashhead *in_ifaddrhashtbl; 230u_long in_multihash; /* size of hash table - 1 */ 231int in_multientries; /* total number of addrs */ 232struct in_multihashhead *in_multihashtbl; 233struct ifqueue ipintrq; 234uint16_t ip_id; 235 236percpu_t *ipstat_percpu; 237 238#ifdef PFIL_HOOKS 239struct pfil_head inet_pfil_hook; 240#endif 241 242/* 243 * Cached copy of nmbclusters. If nbclusters is different, 244 * recalculate IP parameters derived from nmbclusters. 245 */ 246static int ip_nmbclusters; /* copy of nmbclusters */ 247static void ip_nmbclusters_changed(void); /* recalc limits */ 248 249#define CHECK_NMBCLUSTER_PARAMS() \ 250do { \ 251 if (__predict_false(ip_nmbclusters != nmbclusters)) \ 252 ip_nmbclusters_changed(); \ 253} while (/*CONSTCOND*/0) 254 255/* IP datagram reassembly queues (hashed) */ 256#define IPREASS_NHASH_LOG2 6 257#define IPREASS_NHASH (1 << IPREASS_NHASH_LOG2) 258#define IPREASS_HMASK (IPREASS_NHASH - 1) 259#define IPREASS_HASH(x,y) \ 260 (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK) 261struct ipqhead ipq[IPREASS_NHASH]; 262int ipq_locked; 263static int ip_nfragpackets; /* packets in reass queue */ 264static int ip_nfrags; /* total fragments in reass queues */ 265 266int ip_maxfragpackets = 200; /* limit on packets. XXX sysctl */ 267int ip_maxfrags; /* limit on fragments. XXX sysctl */ 268 269 270/* 271 * Additive-Increase/Multiplicative-Decrease (AIMD) strategy for 272 * IP reassembly queue buffer managment. 273 * 274 * We keep a count of total IP fragments (NB: not fragmented packets!) 275 * awaiting reassembly (ip_nfrags) and a limit (ip_maxfrags) on fragments. 276 * If ip_nfrags exceeds ip_maxfrags the limit, we drop half the 277 * total fragments in reassembly queues.This AIMD policy avoids 278 * repeatedly deleting single packets under heavy fragmentation load 279 * (e.g., from lossy NFS peers). 280 */ 281static u_int ip_reass_ttl_decr(u_int ticks); 282static void ip_reass_drophalf(void); 283 284 285static inline int ipq_lock_try(void); 286static inline void ipq_unlock(void); 287 288static inline int 289ipq_lock_try(void) 290{ 291 int s; 292 293 /* 294 * Use splvm() -- we're blocking things that would cause 295 * mbuf allocation. 296 */ 297 s = splvm(); 298 if (ipq_locked) { 299 splx(s); 300 return (0); 301 } 302 ipq_locked = 1; 303 splx(s); 304 return (1); 305} 306 307static inline void 308ipq_unlock(void) 309{ 310 int s; 311 312 s = splvm(); 313 ipq_locked = 0; 314 splx(s); 315} 316 317#ifdef DIAGNOSTIC 318#define IPQ_LOCK() \ 319do { \ 320 if (ipq_lock_try() == 0) { \ 321 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 322 panic("ipq_lock"); \ 323 } \ 324} while (/*CONSTCOND*/ 0) 325#define IPQ_LOCK_CHECK() \ 326do { \ 327 if (ipq_locked == 0) { \ 328 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 329 panic("ipq lock check"); \ 330 } \ 331} while (/*CONSTCOND*/ 0) 332#else 333#define IPQ_LOCK() (void) ipq_lock_try() 334#define IPQ_LOCK_CHECK() /* nothing */ 335#endif 336 337#define IPQ_UNLOCK() ipq_unlock() 338 339POOL_INIT(inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", NULL, 340 IPL_SOFTNET); 341POOL_INIT(ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", NULL, 342 IPL_VM); 343 344#ifdef INET_CSUM_COUNTERS 345#include <sys/device.h> 346 347struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 348 NULL, "inet", "hwcsum bad"); 349struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 350 NULL, "inet", "hwcsum ok"); 351struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 352 NULL, "inet", "swcsum"); 353 354#define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 355 356EVCNT_ATTACH_STATIC(ip_hwcsum_bad); 357EVCNT_ATTACH_STATIC(ip_hwcsum_ok); 358EVCNT_ATTACH_STATIC(ip_swcsum); 359 360#else 361 362#define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 363 364#endif /* INET_CSUM_COUNTERS */ 365 366/* 367 * We need to save the IP options in case a protocol wants to respond 368 * to an incoming packet over the same route if the packet got here 369 * using IP source routing. This allows connection establishment and 370 * maintenance when the remote end is on a network that is not known 371 * to us. 372 */ 373int ip_nhops = 0; 374static struct ip_srcrt { 375 struct in_addr dst; /* final destination */ 376 char nop; /* one NOP to align */ 377 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 378 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 379} ip_srcrt; 380 381static void save_rte(u_char *, struct in_addr); 382 383#ifdef MBUFTRACE 384struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx"); 385struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx"); 386#endif 387 388/* 389 * Compute IP limits derived from the value of nmbclusters. 390 */ 391static void 392ip_nmbclusters_changed(void) 393{ 394 ip_maxfrags = nmbclusters / 4; 395 ip_nmbclusters = nmbclusters; 396} 397 398/* 399 * IP initialization: fill in IP protocol switch table. 400 * All protocols not implemented in kernel go to raw IP protocol handler. 401 */ 402void 403ip_init(void) 404{ 405 const struct protosw *pr; 406 int i; 407 408 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 409 if (pr == 0) 410 panic("ip_init"); 411 for (i = 0; i < IPPROTO_MAX; i++) 412 ip_protox[i] = pr - inetsw; 413 for (pr = inetdomain.dom_protosw; 414 pr < inetdomain.dom_protoswNPROTOSW; pr++) 415 if (pr->pr_domain->dom_family == PF_INET && 416 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 417 ip_protox[pr->pr_protocol] = pr - inetsw; 418 419 for (i = 0; i < IPREASS_NHASH; i++) 420 LIST_INIT(&ipq[i]); 421 422 ip_initid(); 423 ip_id = time_second & 0xfffff; 424 425 ipintrq.ifq_maxlen = ipqmaxlen; 426 ip_nmbclusters_changed(); 427 428 TAILQ_INIT(&in_ifaddrhead); 429 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR, 430 M_WAITOK, &in_ifaddrhash); 431 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IPMADDR, 432 M_WAITOK, &in_multihash); 433 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 434#ifdef GATEWAY 435 ipflow_init(ip_hashsize); 436#endif 437 438#ifdef PFIL_HOOKS 439 /* Register our Packet Filter hook. */ 440 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 441 inet_pfil_hook.ph_af = AF_INET; 442 i = pfil_head_register(&inet_pfil_hook); 443 if (i != 0) 444 printf("ip_init: WARNING: unable to register pfil hook, " 445 "error %d\n", i); 446#endif /* PFIL_HOOKS */ 447 448#ifdef MBUFTRACE 449 MOWNER_ATTACH(&ip_tx_mowner); 450 MOWNER_ATTACH(&ip_rx_mowner); 451#endif /* MBUFTRACE */ 452 453 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS); 454} 455 456struct sockaddr_in ipaddr = { 457 .sin_len = sizeof(ipaddr), 458 .sin_family = AF_INET, 459}; 460struct route ipforward_rt; 461 462/* 463 * IP software interrupt routine 464 */ 465void 466ipintr(void) 467{ 468 int s; 469 struct mbuf *m; 470 471 while (!IF_IS_EMPTY(&ipintrq)) { 472 s = splnet(); 473 IF_DEQUEUE(&ipintrq, m); 474 splx(s); 475 if (m == 0) 476 return; 477 ip_input(m); 478 } 479} 480 481/* 482 * Ip input routine. Checksum and byte swap header. If fragmented 483 * try to reassemble. Process options. Pass to next level. 484 */ 485void 486ip_input(struct mbuf *m) 487{ 488 struct ip *ip = NULL; 489 struct ipq *fp; 490 struct in_ifaddr *ia; 491 struct ifaddr *ifa; 492 struct ipqent *ipqe; 493 int hlen = 0, mff, len; 494 int downmatch; 495 int checkif; 496 int srcrt = 0; 497 int s; 498 u_int hash; 499#ifdef FAST_IPSEC 500 struct m_tag *mtag; 501 struct tdb_ident *tdbi; 502 struct secpolicy *sp; 503 int error; 504#endif /* FAST_IPSEC */ 505 506 MCLAIM(m, &ip_rx_mowner); 507#ifdef DIAGNOSTIC 508 if ((m->m_flags & M_PKTHDR) == 0) 509 panic("ipintr no HDR"); 510#endif 511 512 /* 513 * If no IP addresses have been set yet but the interfaces 514 * are receiving, can't do anything with incoming packets yet. 515 */ 516 if (TAILQ_FIRST(&in_ifaddrhead) == 0) 517 goto bad; 518 IP_STATINC(IP_STAT_TOTAL); 519 /* 520 * If the IP header is not aligned, slurp it up into a new 521 * mbuf with space for link headers, in the event we forward 522 * it. Otherwise, if it is aligned, make sure the entire 523 * base IP header is in the first mbuf of the chain. 524 */ 525 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) { 526 if ((m = m_copyup(m, sizeof(struct ip), 527 (max_linkhdr + 3) & ~3)) == NULL) { 528 /* XXXJRT new stat, please */ 529 IP_STATINC(IP_STAT_TOOSMALL); 530 return; 531 } 532 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 533 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 534 IP_STATINC(IP_STAT_TOOSMALL); 535 return; 536 } 537 } 538 ip = mtod(m, struct ip *); 539 if (ip->ip_v != IPVERSION) { 540 IP_STATINC(IP_STAT_BADVERS); 541 goto bad; 542 } 543 hlen = ip->ip_hl << 2; 544 if (hlen < sizeof(struct ip)) { /* minimum header length */ 545 IP_STATINC(IP_STAT_BADHLEN); 546 goto bad; 547 } 548 if (hlen > m->m_len) { 549 if ((m = m_pullup(m, hlen)) == 0) { 550 IP_STATINC(IP_STAT_BADHLEN); 551 return; 552 } 553 ip = mtod(m, struct ip *); 554 } 555 556 /* 557 * RFC1122: packets with a multicast source address are 558 * not allowed. 559 */ 560 if (IN_MULTICAST(ip->ip_src.s_addr)) { 561 IP_STATINC(IP_STAT_BADADDR); 562 goto bad; 563 } 564 565 /* 127/8 must not appear on wire - RFC1122 */ 566 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 567 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 568 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 569 IP_STATINC(IP_STAT_BADADDR); 570 goto bad; 571 } 572 } 573 574 switch (m->m_pkthdr.csum_flags & 575 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 576 M_CSUM_IPv4_BAD)) { 577 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 578 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 579 goto badcsum; 580 581 case M_CSUM_IPv4: 582 /* Checksum was okay. */ 583 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 584 break; 585 586 default: 587 /* 588 * Must compute it ourselves. Maybe skip checksum on 589 * loopback interfaces. 590 */ 591 if (__predict_true(!(m->m_pkthdr.rcvif->if_flags & 592 IFF_LOOPBACK) || ip_do_loopback_cksum)) { 593 INET_CSUM_COUNTER_INCR(&ip_swcsum); 594 if (in_cksum(m, hlen) != 0) 595 goto badcsum; 596 } 597 break; 598 } 599 600 /* Retrieve the packet length. */ 601 len = ntohs(ip->ip_len); 602 603 /* 604 * Check for additional length bogosity 605 */ 606 if (len < hlen) { 607 IP_STATINC(IP_STAT_BADLEN); 608 goto bad; 609 } 610 611 /* 612 * Check that the amount of data in the buffers 613 * is as at least much as the IP header would have us expect. 614 * Trim mbufs if longer than we expect. 615 * Drop packet if shorter than we expect. 616 */ 617 if (m->m_pkthdr.len < len) { 618 IP_STATINC(IP_STAT_TOOSHORT); 619 goto bad; 620 } 621 if (m->m_pkthdr.len > len) { 622 if (m->m_len == m->m_pkthdr.len) { 623 m->m_len = len; 624 m->m_pkthdr.len = len; 625 } else 626 m_adj(m, len - m->m_pkthdr.len); 627 } 628 629#if defined(IPSEC) 630 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 631 m->m_flags &= ~M_CANFASTFWD; 632#else 633 /* 634 * Assume that we can create a fast-forward IP flow entry 635 * based on this packet. 636 */ 637 m->m_flags |= M_CANFASTFWD; 638#endif 639 640#ifdef PFIL_HOOKS 641 /* 642 * Run through list of hooks for input packets. If there are any 643 * filters which require that additional packets in the flow are 644 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 645 * Note that filters must _never_ set this flag, as another filter 646 * in the list may have previously cleared it. 647 */ 648 /* 649 * let ipfilter look at packet on the wire, 650 * not the decapsulated packet. 651 */ 652#ifdef IPSEC 653 if (!ipsec_getnhist(m)) 654#elif defined(FAST_IPSEC) 655 if (!ipsec_indone(m)) 656#else 657 if (1) 658#endif 659 { 660 struct in_addr odst; 661 662 odst = ip->ip_dst; 663 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 664 PFIL_IN) != 0) 665 return; 666 if (m == NULL) 667 return; 668 ip = mtod(m, struct ip *); 669 hlen = ip->ip_hl << 2; 670 /* 671 * XXX The setting of "srcrt" here is to prevent ip_forward() 672 * from generating ICMP redirects for packets that have 673 * been redirected by a hook back out on to the same LAN that 674 * they came from and is not an indication that the packet 675 * is being inffluenced by source routing options. This 676 * allows things like 677 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp" 678 * where tlp0 is both on the 1.1.1.0/24 network and is the 679 * default route for hosts on 1.1.1.0/24. Of course this 680 * also requires a "map tlp0 ..." to complete the story. 681 * One might argue whether or not this kind of network config. 682 * should be supported in this manner... 683 */ 684 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 685 } 686#endif /* PFIL_HOOKS */ 687 688#ifdef ALTQ 689 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 690 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 691 /* packet dropped by traffic conditioner */ 692 return; 693 } 694#endif 695 696 /* 697 * Process options and, if not destined for us, 698 * ship it on. ip_dooptions returns 1 when an 699 * error was detected (causing an icmp message 700 * to be sent and the original packet to be freed). 701 */ 702 ip_nhops = 0; /* for source routed packets */ 703 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 704 return; 705 706 /* 707 * Enable a consistency check between the destination address 708 * and the arrival interface for a unicast packet (the RFC 1122 709 * strong ES model) if IP forwarding is disabled and the packet 710 * is not locally generated. 711 * 712 * XXX - Checking also should be disabled if the destination 713 * address is ipnat'ed to a different interface. 714 * 715 * XXX - Checking is incompatible with IP aliases added 716 * to the loopback interface instead of the interface where 717 * the packets are received. 718 * 719 * XXX - We need to add a per ifaddr flag for this so that 720 * we get finer grain control. 721 */ 722 checkif = ip_checkinterface && (ipforwarding == 0) && 723 (m->m_pkthdr.rcvif != NULL) && 724 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 725 726 /* 727 * Check our list of addresses, to see if the packet is for us. 728 * 729 * Traditional 4.4BSD did not consult IFF_UP at all. 730 * The behavior here is to treat addresses on !IFF_UP interface 731 * as not mine. 732 */ 733 downmatch = 0; 734 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 735 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 736 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 737 continue; 738 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 739 break; 740 else 741 downmatch++; 742 } 743 } 744 if (ia != NULL) 745 goto ours; 746 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 747 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 748 if (ifa->ifa_addr->sa_family != AF_INET) 749 continue; 750 ia = ifatoia(ifa); 751 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 752 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 753 /* 754 * Look for all-0's host part (old broadcast addr), 755 * either for subnet or net. 756 */ 757 ip->ip_dst.s_addr == ia->ia_subnet || 758 ip->ip_dst.s_addr == ia->ia_net) 759 goto ours; 760 /* 761 * An interface with IP address zero accepts 762 * all packets that arrive on that interface. 763 */ 764 if (in_nullhost(ia->ia_addr.sin_addr)) 765 goto ours; 766 } 767 } 768 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 769 struct in_multi *inm; 770#ifdef MROUTING 771 extern struct socket *ip_mrouter; 772 773 if (ip_mrouter) { 774 /* 775 * If we are acting as a multicast router, all 776 * incoming multicast packets are passed to the 777 * kernel-level multicast forwarding function. 778 * The packet is returned (relatively) intact; if 779 * ip_mforward() returns a non-zero value, the packet 780 * must be discarded, else it may be accepted below. 781 * 782 * (The IP ident field is put in the same byte order 783 * as expected when ip_mforward() is called from 784 * ip_output().) 785 */ 786 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 787 IP_STATINC(IP_STAT_CANTFORWARD); 788 m_freem(m); 789 return; 790 } 791 792 /* 793 * The process-level routing demon needs to receive 794 * all multicast IGMP packets, whether or not this 795 * host belongs to their destination groups. 796 */ 797 if (ip->ip_p == IPPROTO_IGMP) 798 goto ours; 799 IP_STATINC(IP_STAT_CANTFORWARD); 800 } 801#endif 802 /* 803 * See if we belong to the destination multicast group on the 804 * arrival interface. 805 */ 806 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 807 if (inm == NULL) { 808 IP_STATINC(IP_STAT_CANTFORWARD); 809 m_freem(m); 810 return; 811 } 812 goto ours; 813 } 814 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 815 in_nullhost(ip->ip_dst)) 816 goto ours; 817 818 /* 819 * Not for us; forward if possible and desirable. 820 */ 821 if (ipforwarding == 0) { 822 IP_STATINC(IP_STAT_CANTFORWARD); 823 m_freem(m); 824 } else { 825 /* 826 * If ip_dst matched any of my address on !IFF_UP interface, 827 * and there's no IFF_UP interface that matches ip_dst, 828 * send icmp unreach. Forwarding it will result in in-kernel 829 * forwarding loop till TTL goes to 0. 830 */ 831 if (downmatch) { 832 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 833 IP_STATINC(IP_STAT_CANTFORWARD); 834 return; 835 } 836#ifdef IPSEC 837 if (ipsec4_in_reject(m, NULL)) { 838 ipsecstat.in_polvio++; 839 goto bad; 840 } 841#endif 842#ifdef FAST_IPSEC 843 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 844 s = splsoftnet(); 845 if (mtag != NULL) { 846 tdbi = (struct tdb_ident *)(mtag + 1); 847 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 848 } else { 849 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 850 IP_FORWARDING, &error); 851 } 852 if (sp == NULL) { /* NB: can happen if error */ 853 splx(s); 854 /*XXX error stat???*/ 855 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/ 856 goto bad; 857 } 858 859 /* 860 * Check security policy against packet attributes. 861 */ 862 error = ipsec_in_reject(sp, m); 863 KEY_FREESP(&sp); 864 splx(s); 865 if (error) { 866 IP_STATINC(IP_STAT_CANTFORWARD); 867 goto bad; 868 } 869 870 /* 871 * Peek at the outbound SP for this packet to determine if 872 * it's a Fast Forward candidate. 873 */ 874 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 875 if (mtag != NULL) 876 m->m_flags &= ~M_CANFASTFWD; 877 else { 878 s = splsoftnet(); 879 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, 880 (IP_FORWARDING | 881 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 882 &error, NULL); 883 if (sp != NULL) { 884 m->m_flags &= ~M_CANFASTFWD; 885 KEY_FREESP(&sp); 886 } 887 splx(s); 888 } 889#endif /* FAST_IPSEC */ 890 891 ip_forward(m, srcrt); 892 } 893 return; 894 895ours: 896 /* 897 * If offset or IP_MF are set, must reassemble. 898 * Otherwise, nothing need be done. 899 * (We could look in the reassembly queue to see 900 * if the packet was previously fragmented, 901 * but it's not worth the time; just let them time out.) 902 */ 903 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 904 uint16_t off; 905 /* 906 * Prevent TCP blind data attacks by not allowing non-initial 907 * fragments to start at less than 68 bytes (minimal fragment 908 * size) and making sure the first fragment is at least 68 909 * bytes. 910 */ 911 off = (ntohs(ip->ip_off) & IP_OFFMASK) << 3; 912 if ((off > 0 ? off + hlen : len) < IP_MINFRAGSIZE - 1) { 913 IP_STATINC(IP_STAT_BADFRAGS); 914 goto bad; 915 } 916 /* 917 * Look for queue of fragments 918 * of this datagram. 919 */ 920 IPQ_LOCK(); 921 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id); 922 LIST_FOREACH(fp, &ipq[hash], ipq_q) { 923 if (ip->ip_id == fp->ipq_id && 924 in_hosteq(ip->ip_src, fp->ipq_src) && 925 in_hosteq(ip->ip_dst, fp->ipq_dst) && 926 ip->ip_p == fp->ipq_p) { 927 /* 928 * Make sure the TOS is matches previous 929 * fragments. 930 */ 931 if (ip->ip_tos != fp->ipq_tos) { 932 IP_STATINC(IP_STAT_BADFRAGS); 933 goto bad; 934 } 935 goto found; 936 } 937 } 938 fp = 0; 939found: 940 941 /* 942 * Adjust ip_len to not reflect header, 943 * set ipqe_mff if more fragments are expected, 944 * convert offset of this to bytes. 945 */ 946 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 947 mff = (ip->ip_off & htons(IP_MF)) != 0; 948 if (mff) { 949 /* 950 * Make sure that fragments have a data length 951 * that's a non-zero multiple of 8 bytes. 952 */ 953 if (ntohs(ip->ip_len) == 0 || 954 (ntohs(ip->ip_len) & 0x7) != 0) { 955 IP_STATINC(IP_STAT_BADFRAGS); 956 IPQ_UNLOCK(); 957 goto bad; 958 } 959 } 960 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 961 962 /* 963 * If datagram marked as having more fragments 964 * or if this is not the first fragment, 965 * attempt reassembly; if it succeeds, proceed. 966 */ 967 if (mff || ip->ip_off != htons(0)) { 968 IP_STATINC(IP_STAT_FRAGMENTS); 969 s = splvm(); 970 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 971 splx(s); 972 if (ipqe == NULL) { 973 IP_STATINC(IP_STAT_RCVMEMDROP); 974 IPQ_UNLOCK(); 975 goto bad; 976 } 977 ipqe->ipqe_mff = mff; 978 ipqe->ipqe_m = m; 979 ipqe->ipqe_ip = ip; 980 m = ip_reass(ipqe, fp, &ipq[hash]); 981 if (m == 0) { 982 IPQ_UNLOCK(); 983 return; 984 } 985 IP_STATINC(IP_STAT_REASSEMBLED); 986 ip = mtod(m, struct ip *); 987 hlen = ip->ip_hl << 2; 988 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 989 } else 990 if (fp) 991 ip_freef(fp); 992 IPQ_UNLOCK(); 993 } 994 995#if defined(IPSEC) 996 /* 997 * enforce IPsec policy checking if we are seeing last header. 998 * note that we do not visit this with protocols with pcb layer 999 * code - like udp/tcp/raw ip. 1000 */ 1001 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 1002 ipsec4_in_reject(m, NULL)) { 1003 ipsecstat.in_polvio++; 1004 goto bad; 1005 } 1006#endif 1007#ifdef FAST_IPSEC 1008 /* 1009 * enforce IPsec policy checking if we are seeing last header. 1010 * note that we do not visit this with protocols with pcb layer 1011 * code - like udp/tcp/raw ip. 1012 */ 1013 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 1014 /* 1015 * Check if the packet has already had IPsec processing 1016 * done. If so, then just pass it along. This tag gets 1017 * set during AH, ESP, etc. input handling, before the 1018 * packet is returned to the ip input queue for delivery. 1019 */ 1020 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 1021 s = splsoftnet(); 1022 if (mtag != NULL) { 1023 tdbi = (struct tdb_ident *)(mtag + 1); 1024 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 1025 } else { 1026 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1027 IP_FORWARDING, &error); 1028 } 1029 if (sp != NULL) { 1030 /* 1031 * Check security policy against packet attributes. 1032 */ 1033 error = ipsec_in_reject(sp, m); 1034 KEY_FREESP(&sp); 1035 } else { 1036 /* XXX error stat??? */ 1037 error = EINVAL; 1038DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 1039 } 1040 splx(s); 1041 if (error) 1042 goto bad; 1043 } 1044#endif /* FAST_IPSEC */ 1045 1046 /* 1047 * Switch out to protocol's input routine. 1048 */ 1049#if IFA_STATS 1050 if (ia && ip) 1051 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 1052#endif 1053 IP_STATINC(IP_STAT_DELIVERED); 1054 { 1055 int off = hlen, nh = ip->ip_p; 1056 1057 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 1058 return; 1059 } 1060bad: 1061 m_freem(m); 1062 return; 1063 1064badcsum: 1065 IP_STATINC(IP_STAT_BADSUM); 1066 m_freem(m); 1067} 1068 1069/* 1070 * Take incoming datagram fragment and try to 1071 * reassemble it into whole datagram. If a chain for 1072 * reassembly of this datagram already exists, then it 1073 * is given as fp; otherwise have to make a chain. 1074 */ 1075struct mbuf * 1076ip_reass(struct ipqent *ipqe, struct ipq *fp, struct ipqhead *ipqhead) 1077{ 1078 struct mbuf *m = ipqe->ipqe_m; 1079 struct ipqent *nq, *p, *q; 1080 struct ip *ip; 1081 struct mbuf *t; 1082 int hlen = ipqe->ipqe_ip->ip_hl << 2; 1083 int i, next, s; 1084 1085 IPQ_LOCK_CHECK(); 1086 1087 /* 1088 * Presence of header sizes in mbufs 1089 * would confuse code below. 1090 */ 1091 m->m_data += hlen; 1092 m->m_len -= hlen; 1093 1094#ifdef notyet 1095 /* make sure fragment limit is up-to-date */ 1096 CHECK_NMBCLUSTER_PARAMS(); 1097 1098 /* If we have too many fragments, drop the older half. */ 1099 if (ip_nfrags >= ip_maxfrags) 1100 ip_reass_drophalf(void); 1101#endif 1102 1103 /* 1104 * We are about to add a fragment; increment frag count. 1105 */ 1106 ip_nfrags++; 1107 1108 /* 1109 * If first fragment to arrive, create a reassembly queue. 1110 */ 1111 if (fp == 0) { 1112 /* 1113 * Enforce upper bound on number of fragmented packets 1114 * for which we attempt reassembly; 1115 * If maxfrag is 0, never accept fragments. 1116 * If maxfrag is -1, accept all fragments without limitation. 1117 */ 1118 if (ip_maxfragpackets < 0) 1119 ; 1120 else if (ip_nfragpackets >= ip_maxfragpackets) 1121 goto dropfrag; 1122 ip_nfragpackets++; 1123 MALLOC(fp, struct ipq *, sizeof (struct ipq), 1124 M_FTABLE, M_NOWAIT); 1125 if (fp == NULL) 1126 goto dropfrag; 1127 LIST_INSERT_HEAD(ipqhead, fp, ipq_q); 1128 fp->ipq_nfrags = 1; 1129 fp->ipq_ttl = IPFRAGTTL; 1130 fp->ipq_p = ipqe->ipqe_ip->ip_p; 1131 fp->ipq_id = ipqe->ipqe_ip->ip_id; 1132 fp->ipq_tos = ipqe->ipqe_ip->ip_tos; 1133 TAILQ_INIT(&fp->ipq_fragq); 1134 fp->ipq_src = ipqe->ipqe_ip->ip_src; 1135 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 1136 p = NULL; 1137 goto insert; 1138 } else { 1139 fp->ipq_nfrags++; 1140 } 1141 1142 /* 1143 * Find a segment which begins after this one does. 1144 */ 1145 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1146 p = q, q = TAILQ_NEXT(q, ipqe_q)) 1147 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 1148 break; 1149 1150 /* 1151 * If there is a preceding segment, it may provide some of 1152 * our data already. If so, drop the data from the incoming 1153 * segment. If it provides all of our data, drop us. 1154 */ 1155 if (p != NULL) { 1156 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 1157 ntohs(ipqe->ipqe_ip->ip_off); 1158 if (i > 0) { 1159 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 1160 goto dropfrag; 1161 m_adj(ipqe->ipqe_m, i); 1162 ipqe->ipqe_ip->ip_off = 1163 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 1164 ipqe->ipqe_ip->ip_len = 1165 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 1166 } 1167 } 1168 1169 /* 1170 * While we overlap succeeding segments trim them or, 1171 * if they are completely covered, dequeue them. 1172 */ 1173 for (; q != NULL && 1174 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 1175 ntohs(q->ipqe_ip->ip_off); q = nq) { 1176 i = (ntohs(ipqe->ipqe_ip->ip_off) + 1177 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 1178 if (i < ntohs(q->ipqe_ip->ip_len)) { 1179 q->ipqe_ip->ip_len = 1180 htons(ntohs(q->ipqe_ip->ip_len) - i); 1181 q->ipqe_ip->ip_off = 1182 htons(ntohs(q->ipqe_ip->ip_off) + i); 1183 m_adj(q->ipqe_m, i); 1184 break; 1185 } 1186 nq = TAILQ_NEXT(q, ipqe_q); 1187 m_freem(q->ipqe_m); 1188 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1189 s = splvm(); 1190 pool_put(&ipqent_pool, q); 1191 splx(s); 1192 fp->ipq_nfrags--; 1193 ip_nfrags--; 1194 } 1195 1196insert: 1197 /* 1198 * Stick new segment in its place; 1199 * check for complete reassembly. 1200 */ 1201 if (p == NULL) { 1202 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1203 } else { 1204 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1205 } 1206 next = 0; 1207 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1208 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1209 if (ntohs(q->ipqe_ip->ip_off) != next) 1210 return (0); 1211 next += ntohs(q->ipqe_ip->ip_len); 1212 } 1213 if (p->ipqe_mff) 1214 return (0); 1215 1216 /* 1217 * Reassembly is complete. Check for a bogus message size and 1218 * concatenate fragments. 1219 */ 1220 q = TAILQ_FIRST(&fp->ipq_fragq); 1221 ip = q->ipqe_ip; 1222 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1223 IP_STATINC(IP_STAT_TOOLONG); 1224 ip_freef(fp); 1225 return (0); 1226 } 1227 m = q->ipqe_m; 1228 t = m->m_next; 1229 m->m_next = 0; 1230 m_cat(m, t); 1231 nq = TAILQ_NEXT(q, ipqe_q); 1232 s = splvm(); 1233 pool_put(&ipqent_pool, q); 1234 splx(s); 1235 for (q = nq; q != NULL; q = nq) { 1236 t = q->ipqe_m; 1237 nq = TAILQ_NEXT(q, ipqe_q); 1238 s = splvm(); 1239 pool_put(&ipqent_pool, q); 1240 splx(s); 1241 m_cat(m, t); 1242 } 1243 ip_nfrags -= fp->ipq_nfrags; 1244 1245 /* 1246 * Create header for new ip packet by 1247 * modifying header of first packet; 1248 * dequeue and discard fragment reassembly header. 1249 * Make header visible. 1250 */ 1251 ip->ip_len = htons(next); 1252 ip->ip_src = fp->ipq_src; 1253 ip->ip_dst = fp->ipq_dst; 1254 LIST_REMOVE(fp, ipq_q); 1255 FREE(fp, M_FTABLE); 1256 ip_nfragpackets--; 1257 m->m_len += (ip->ip_hl << 2); 1258 m->m_data -= (ip->ip_hl << 2); 1259 /* some debugging cruft by sklower, below, will go away soon */ 1260 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1261 int plen = 0; 1262 for (t = m; t; t = t->m_next) 1263 plen += t->m_len; 1264 m->m_pkthdr.len = plen; 1265 m->m_pkthdr.csum_flags = 0; 1266 } 1267 return (m); 1268 1269dropfrag: 1270 if (fp != 0) 1271 fp->ipq_nfrags--; 1272 ip_nfrags--; 1273 IP_STATINC(IP_STAT_FRAGDROPPED); 1274 m_freem(m); 1275 s = splvm(); 1276 pool_put(&ipqent_pool, ipqe); 1277 splx(s); 1278 return (0); 1279} 1280 1281/* 1282 * Free a fragment reassembly header and all 1283 * associated datagrams. 1284 */ 1285void 1286ip_freef(struct ipq *fp) 1287{ 1288 struct ipqent *q, *p; 1289 u_int nfrags = 0; 1290 int s; 1291 1292 IPQ_LOCK_CHECK(); 1293 1294 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1295 p = TAILQ_NEXT(q, ipqe_q); 1296 m_freem(q->ipqe_m); 1297 nfrags++; 1298 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1299 s = splvm(); 1300 pool_put(&ipqent_pool, q); 1301 splx(s); 1302 } 1303 1304 if (nfrags != fp->ipq_nfrags) 1305 printf("ip_freef: nfrags %d != %d\n", fp->ipq_nfrags, nfrags); 1306 ip_nfrags -= nfrags; 1307 LIST_REMOVE(fp, ipq_q); 1308 FREE(fp, M_FTABLE); 1309 ip_nfragpackets--; 1310} 1311 1312/* 1313 * IP reassembly TTL machinery for multiplicative drop. 1314 */ 1315static u_int fragttl_histo[(IPFRAGTTL+1)]; 1316 1317 1318/* 1319 * Decrement TTL of all reasembly queue entries by `ticks'. 1320 * Count number of distinct fragments (as opposed to partial, fragmented 1321 * datagrams) in the reassembly queue. While we traverse the entire 1322 * reassembly queue, compute and return the median TTL over all fragments. 1323 */ 1324static u_int 1325ip_reass_ttl_decr(u_int ticks) 1326{ 1327 u_int nfrags, median, dropfraction, keepfraction; 1328 struct ipq *fp, *nfp; 1329 int i; 1330 1331 nfrags = 0; 1332 memset(fragttl_histo, 0, sizeof fragttl_histo); 1333 1334 for (i = 0; i < IPREASS_NHASH; i++) { 1335 for (fp = LIST_FIRST(&ipq[i]); fp != NULL; fp = nfp) { 1336 fp->ipq_ttl = ((fp->ipq_ttl <= ticks) ? 1337 0 : fp->ipq_ttl - ticks); 1338 nfp = LIST_NEXT(fp, ipq_q); 1339 if (fp->ipq_ttl == 0) { 1340 IP_STATINC(IP_STAT_FRAGTIMEOUT); 1341 ip_freef(fp); 1342 } else { 1343 nfrags += fp->ipq_nfrags; 1344 fragttl_histo[fp->ipq_ttl] += fp->ipq_nfrags; 1345 } 1346 } 1347 } 1348 1349 KASSERT(ip_nfrags == nfrags); 1350 1351 /* Find median (or other drop fraction) in histogram. */ 1352 dropfraction = (ip_nfrags / 2); 1353 keepfraction = ip_nfrags - dropfraction; 1354 for (i = IPFRAGTTL, median = 0; i >= 0; i--) { 1355 median += fragttl_histo[i]; 1356 if (median >= keepfraction) 1357 break; 1358 } 1359 1360 /* Return TTL of median (or other fraction). */ 1361 return (u_int)i; 1362} 1363 1364void 1365ip_reass_drophalf(void) 1366{ 1367 1368 u_int median_ticks; 1369 /* 1370 * Compute median TTL of all fragments, and count frags 1371 * with that TTL or lower (roughly half of all fragments). 1372 */ 1373 median_ticks = ip_reass_ttl_decr(0); 1374 1375 /* Drop half. */ 1376 median_ticks = ip_reass_ttl_decr(median_ticks); 1377 1378} 1379 1380/* 1381 * IP timer processing; 1382 * if a timer expires on a reassembly 1383 * queue, discard it. 1384 */ 1385void 1386ip_slowtimo(void) 1387{ 1388 static u_int dropscanidx = 0; 1389 u_int i; 1390 u_int median_ttl; 1391 int s = splsoftnet(); 1392 1393 IPQ_LOCK(); 1394 1395 /* Age TTL of all fragments by 1 tick .*/ 1396 median_ttl = ip_reass_ttl_decr(1); 1397 1398 /* make sure fragment limit is up-to-date */ 1399 CHECK_NMBCLUSTER_PARAMS(); 1400 1401 /* If we have too many fragments, drop the older half. */ 1402 if (ip_nfrags > ip_maxfrags) 1403 ip_reass_ttl_decr(median_ttl); 1404 1405 /* 1406 * If we are over the maximum number of fragmented packets 1407 * (due to the limit being lowered), drain off 1408 * enough to get down to the new limit. Start draining 1409 * from the reassembly hashqueue most recently drained. 1410 */ 1411 if (ip_maxfragpackets < 0) 1412 ; 1413 else { 1414 int wrapped = 0; 1415 1416 i = dropscanidx; 1417 while (ip_nfragpackets > ip_maxfragpackets && wrapped == 0) { 1418 while (LIST_FIRST(&ipq[i]) != NULL) 1419 ip_freef(LIST_FIRST(&ipq[i])); 1420 if (++i >= IPREASS_NHASH) { 1421 i = 0; 1422 } 1423 /* 1424 * Dont scan forever even if fragment counters are 1425 * wrong: stop after scanning entire reassembly queue. 1426 */ 1427 if (i == dropscanidx) 1428 wrapped = 1; 1429 } 1430 dropscanidx = i; 1431 } 1432 IPQ_UNLOCK(); 1433 splx(s); 1434} 1435 1436/* 1437 * Drain off all datagram fragments. 1438 */ 1439void 1440ip_drain(void) 1441{ 1442 1443 /* 1444 * We may be called from a device's interrupt context. If 1445 * the ipq is already busy, just bail out now. 1446 */ 1447 if (ipq_lock_try() == 0) 1448 return; 1449 1450 /* 1451 * Drop half the total fragments now. If more mbufs are needed, 1452 * we will be called again soon. 1453 */ 1454 ip_reass_drophalf(); 1455 1456 IPQ_UNLOCK(); 1457} 1458 1459/* 1460 * Do option processing on a datagram, 1461 * possibly discarding it if bad options are encountered, 1462 * or forwarding it if source-routed. 1463 * Returns 1 if packet has been forwarded/freed, 1464 * 0 if the packet should be processed further. 1465 */ 1466int 1467ip_dooptions(struct mbuf *m) 1468{ 1469 struct ip *ip = mtod(m, struct ip *); 1470 u_char *cp, *cp0; 1471 struct ip_timestamp *ipt; 1472 struct in_ifaddr *ia; 1473 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1474 struct in_addr dst; 1475 n_time ntime; 1476 1477 dst = ip->ip_dst; 1478 cp = (u_char *)(ip + 1); 1479 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1480 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1481 opt = cp[IPOPT_OPTVAL]; 1482 if (opt == IPOPT_EOL) 1483 break; 1484 if (opt == IPOPT_NOP) 1485 optlen = 1; 1486 else { 1487 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1488 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1489 goto bad; 1490 } 1491 optlen = cp[IPOPT_OLEN]; 1492 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1493 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1494 goto bad; 1495 } 1496 } 1497 switch (opt) { 1498 1499 default: 1500 break; 1501 1502 /* 1503 * Source routing with record. 1504 * Find interface with current destination address. 1505 * If none on this machine then drop if strictly routed, 1506 * or do nothing if loosely routed. 1507 * Record interface address and bring up next address 1508 * component. If strictly routed make sure next 1509 * address is on directly accessible net. 1510 */ 1511 case IPOPT_LSRR: 1512 case IPOPT_SSRR: 1513 if (ip_allowsrcrt == 0) { 1514 type = ICMP_UNREACH; 1515 code = ICMP_UNREACH_NET_PROHIB; 1516 goto bad; 1517 } 1518 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1519 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1520 goto bad; 1521 } 1522 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1523 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1524 goto bad; 1525 } 1526 ipaddr.sin_addr = ip->ip_dst; 1527 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1528 if (ia == 0) { 1529 if (opt == IPOPT_SSRR) { 1530 type = ICMP_UNREACH; 1531 code = ICMP_UNREACH_SRCFAIL; 1532 goto bad; 1533 } 1534 /* 1535 * Loose routing, and not at next destination 1536 * yet; nothing to do except forward. 1537 */ 1538 break; 1539 } 1540 off--; /* 0 origin */ 1541 if ((off + sizeof(struct in_addr)) > optlen) { 1542 /* 1543 * End of source route. Should be for us. 1544 */ 1545 save_rte(cp, ip->ip_src); 1546 break; 1547 } 1548 /* 1549 * locate outgoing interface 1550 */ 1551 bcopy((void *)(cp + off), (void *)&ipaddr.sin_addr, 1552 sizeof(ipaddr.sin_addr)); 1553 if (opt == IPOPT_SSRR) 1554 ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr))); 1555 else 1556 ia = ip_rtaddr(ipaddr.sin_addr); 1557 if (ia == 0) { 1558 type = ICMP_UNREACH; 1559 code = ICMP_UNREACH_SRCFAIL; 1560 goto bad; 1561 } 1562 ip->ip_dst = ipaddr.sin_addr; 1563 bcopy((void *)&ia->ia_addr.sin_addr, 1564 (void *)(cp + off), sizeof(struct in_addr)); 1565 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1566 /* 1567 * Let ip_intr's mcast routing check handle mcast pkts 1568 */ 1569 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1570 break; 1571 1572 case IPOPT_RR: 1573 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1574 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1575 goto bad; 1576 } 1577 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1578 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1579 goto bad; 1580 } 1581 /* 1582 * If no space remains, ignore. 1583 */ 1584 off--; /* 0 origin */ 1585 if ((off + sizeof(struct in_addr)) > optlen) 1586 break; 1587 bcopy((void *)(&ip->ip_dst), (void *)&ipaddr.sin_addr, 1588 sizeof(ipaddr.sin_addr)); 1589 /* 1590 * locate outgoing interface; if we're the destination, 1591 * use the incoming interface (should be same). 1592 */ 1593 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1594 == NULL && 1595 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1596 type = ICMP_UNREACH; 1597 code = ICMP_UNREACH_HOST; 1598 goto bad; 1599 } 1600 bcopy((void *)&ia->ia_addr.sin_addr, 1601 (void *)(cp + off), sizeof(struct in_addr)); 1602 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1603 break; 1604 1605 case IPOPT_TS: 1606 code = cp - (u_char *)ip; 1607 ipt = (struct ip_timestamp *)cp; 1608 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1609 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1610 goto bad; 1611 } 1612 if (ipt->ipt_ptr < 5) { 1613 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1614 goto bad; 1615 } 1616 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1617 if (++ipt->ipt_oflw == 0) { 1618 code = (u_char *)&ipt->ipt_ptr - 1619 (u_char *)ip; 1620 goto bad; 1621 } 1622 break; 1623 } 1624 cp0 = (cp + ipt->ipt_ptr - 1); 1625 switch (ipt->ipt_flg) { 1626 1627 case IPOPT_TS_TSONLY: 1628 break; 1629 1630 case IPOPT_TS_TSANDADDR: 1631 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1632 sizeof(struct in_addr) > ipt->ipt_len) { 1633 code = (u_char *)&ipt->ipt_ptr - 1634 (u_char *)ip; 1635 goto bad; 1636 } 1637 ipaddr.sin_addr = dst; 1638 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1639 m->m_pkthdr.rcvif)); 1640 if (ia == 0) 1641 continue; 1642 bcopy(&ia->ia_addr.sin_addr, 1643 cp0, sizeof(struct in_addr)); 1644 ipt->ipt_ptr += sizeof(struct in_addr); 1645 break; 1646 1647 case IPOPT_TS_PRESPEC: 1648 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1649 sizeof(struct in_addr) > ipt->ipt_len) { 1650 code = (u_char *)&ipt->ipt_ptr - 1651 (u_char *)ip; 1652 goto bad; 1653 } 1654 bcopy(cp0, &ipaddr.sin_addr, 1655 sizeof(struct in_addr)); 1656 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1657 == NULL) 1658 continue; 1659 ipt->ipt_ptr += sizeof(struct in_addr); 1660 break; 1661 1662 default: 1663 /* XXX can't take &ipt->ipt_flg */ 1664 code = (u_char *)&ipt->ipt_ptr - 1665 (u_char *)ip + 1; 1666 goto bad; 1667 } 1668 ntime = iptime(); 1669 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1670 memmove((char *)cp + ipt->ipt_ptr - 1, cp0, 1671 sizeof(n_time)); 1672 ipt->ipt_ptr += sizeof(n_time); 1673 } 1674 } 1675 if (forward) { 1676 if (ip_forwsrcrt == 0) { 1677 type = ICMP_UNREACH; 1678 code = ICMP_UNREACH_SRCFAIL; 1679 goto bad; 1680 } 1681 ip_forward(m, 1); 1682 return (1); 1683 } 1684 return (0); 1685bad: 1686 icmp_error(m, type, code, 0, 0); 1687 IP_STATINC(IP_STAT_BADOPTIONS); 1688 return (1); 1689} 1690 1691/* 1692 * Given address of next destination (final or next hop), 1693 * return internet address info of interface to be used to get there. 1694 */ 1695struct in_ifaddr * 1696ip_rtaddr(struct in_addr dst) 1697{ 1698 struct rtentry *rt; 1699 union { 1700 struct sockaddr dst; 1701 struct sockaddr_in dst4; 1702 } u; 1703 1704 sockaddr_in_init(&u.dst4, &dst, 0); 1705 1706 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) 1707 return NULL; 1708 1709 return ifatoia(rt->rt_ifa); 1710} 1711 1712/* 1713 * Save incoming source route for use in replies, 1714 * to be picked up later by ip_srcroute if the receiver is interested. 1715 */ 1716void 1717save_rte(u_char *option, struct in_addr dst) 1718{ 1719 unsigned olen; 1720 1721 olen = option[IPOPT_OLEN]; 1722#ifdef DIAGNOSTIC 1723 if (ipprintfs) 1724 printf("save_rte: olen %d\n", olen); 1725#endif /* 0 */ 1726 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1727 return; 1728 bcopy((void *)option, (void *)ip_srcrt.srcopt, olen); 1729 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1730 ip_srcrt.dst = dst; 1731} 1732 1733/* 1734 * Retrieve incoming source route for use in replies, 1735 * in the same form used by setsockopt. 1736 * The first hop is placed before the options, will be removed later. 1737 */ 1738struct mbuf * 1739ip_srcroute(void) 1740{ 1741 struct in_addr *p, *q; 1742 struct mbuf *m; 1743 1744 if (ip_nhops == 0) 1745 return NULL; 1746 m = m_get(M_DONTWAIT, MT_SOOPTS); 1747 if (m == 0) 1748 return NULL; 1749 1750 MCLAIM(m, &inetdomain.dom_mowner); 1751#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1752 1753 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1754 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1755 OPTSIZ; 1756#ifdef DIAGNOSTIC 1757 if (ipprintfs) 1758 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1759#endif 1760 1761 /* 1762 * First save first hop for return route 1763 */ 1764 p = &ip_srcrt.route[ip_nhops - 1]; 1765 *(mtod(m, struct in_addr *)) = *p--; 1766#ifdef DIAGNOSTIC 1767 if (ipprintfs) 1768 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1769#endif 1770 1771 /* 1772 * Copy option fields and padding (nop) to mbuf. 1773 */ 1774 ip_srcrt.nop = IPOPT_NOP; 1775 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1776 memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop, 1777 OPTSIZ); 1778 q = (struct in_addr *)(mtod(m, char *) + 1779 sizeof(struct in_addr) + OPTSIZ); 1780#undef OPTSIZ 1781 /* 1782 * Record return path as an IP source route, 1783 * reversing the path (pointers are now aligned). 1784 */ 1785 while (p >= ip_srcrt.route) { 1786#ifdef DIAGNOSTIC 1787 if (ipprintfs) 1788 printf(" %x", ntohl(q->s_addr)); 1789#endif 1790 *q++ = *p--; 1791 } 1792 /* 1793 * Last hop goes to final destination. 1794 */ 1795 *q = ip_srcrt.dst; 1796#ifdef DIAGNOSTIC 1797 if (ipprintfs) 1798 printf(" %x\n", ntohl(q->s_addr)); 1799#endif 1800 return (m); 1801} 1802 1803const int inetctlerrmap[PRC_NCMDS] = { 1804 [PRC_MSGSIZE] = EMSGSIZE, 1805 [PRC_HOSTDEAD] = EHOSTDOWN, 1806 [PRC_HOSTUNREACH] = EHOSTUNREACH, 1807 [PRC_UNREACH_NET] = EHOSTUNREACH, 1808 [PRC_UNREACH_HOST] = EHOSTUNREACH, 1809 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED, 1810 [PRC_UNREACH_PORT] = ECONNREFUSED, 1811 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH, 1812 [PRC_PARAMPROB] = ENOPROTOOPT, 1813}; 1814 1815/* 1816 * Forward a packet. If some error occurs return the sender 1817 * an icmp packet. Note we can't always generate a meaningful 1818 * icmp message because icmp doesn't have a large enough repertoire 1819 * of codes and types. 1820 * 1821 * If not forwarding, just drop the packet. This could be confusing 1822 * if ipforwarding was zero but some routing protocol was advancing 1823 * us as a gateway to somewhere. However, we must let the routing 1824 * protocol deal with that. 1825 * 1826 * The srcrt parameter indicates whether the packet is being forwarded 1827 * via a source route. 1828 */ 1829void 1830ip_forward(struct mbuf *m, int srcrt) 1831{ 1832 struct ip *ip = mtod(m, struct ip *); 1833 struct rtentry *rt; 1834 int error, type = 0, code = 0, destmtu = 0; 1835 struct mbuf *mcopy; 1836 n_long dest; 1837 union { 1838 struct sockaddr dst; 1839 struct sockaddr_in dst4; 1840 } u; 1841 1842 /* 1843 * We are now in the output path. 1844 */ 1845 MCLAIM(m, &ip_tx_mowner); 1846 1847 /* 1848 * Clear any in-bound checksum flags for this packet. 1849 */ 1850 m->m_pkthdr.csum_flags = 0; 1851 1852 dest = 0; 1853#ifdef DIAGNOSTIC 1854 if (ipprintfs) { 1855 printf("forward: src %s ", inet_ntoa(ip->ip_src)); 1856 printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl); 1857 } 1858#endif 1859 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1860 IP_STATINC(IP_STAT_CANTFORWARD); 1861 m_freem(m); 1862 return; 1863 } 1864 if (ip->ip_ttl <= IPTTLDEC) { 1865 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1866 return; 1867 } 1868 1869 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0); 1870 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) { 1871 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0); 1872 return; 1873 } 1874 1875 /* 1876 * Save at most 68 bytes of the packet in case 1877 * we need to generate an ICMP message to the src. 1878 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1879 */ 1880 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1881 if (mcopy) 1882 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1883 1884 ip->ip_ttl -= IPTTLDEC; 1885 1886 /* 1887 * If forwarding packet using same interface that it came in on, 1888 * perhaps should send a redirect to sender to shortcut a hop. 1889 * Only send redirect if source is sending directly to us, 1890 * and if packet was not source routed (or has any options). 1891 * Also, don't send redirect if forwarding using a default route 1892 * or a route modified by a redirect. 1893 */ 1894 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1895 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1896 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) && 1897 ipsendredirects && !srcrt) { 1898 if (rt->rt_ifa && 1899 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1900 ifatoia(rt->rt_ifa)->ia_subnet) { 1901 if (rt->rt_flags & RTF_GATEWAY) 1902 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1903 else 1904 dest = ip->ip_dst.s_addr; 1905 /* 1906 * Router requirements says to only send host 1907 * redirects. 1908 */ 1909 type = ICMP_REDIRECT; 1910 code = ICMP_REDIRECT_HOST; 1911#ifdef DIAGNOSTIC 1912 if (ipprintfs) 1913 printf("redirect (%d) to %x\n", code, 1914 (u_int32_t)dest); 1915#endif 1916 } 1917 } 1918 1919 error = ip_output(m, NULL, &ipforward_rt, 1920 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1921 (struct ip_moptions *)NULL, (struct socket *)NULL); 1922 1923 if (error) 1924 IP_STATINC(IP_STAT_CANTFORWARD); 1925 else { 1926 uint64_t *ips = IP_STAT_GETREF(); 1927 ips[IP_STAT_FORWARD]++; 1928 if (type) { 1929 ips[IP_STAT_REDIRECTSENT]++; 1930 IP_STAT_PUTREF(); 1931 } else { 1932 IP_STAT_PUTREF(); 1933 if (mcopy) { 1934#ifdef GATEWAY 1935 if (mcopy->m_flags & M_CANFASTFWD) 1936 ipflow_create(&ipforward_rt, mcopy); 1937#endif 1938 m_freem(mcopy); 1939 } 1940 return; 1941 } 1942 } 1943 if (mcopy == NULL) 1944 return; 1945 1946 switch (error) { 1947 1948 case 0: /* forwarded, but need redirect */ 1949 /* type, code set above */ 1950 break; 1951 1952 case ENETUNREACH: /* shouldn't happen, checked above */ 1953 case EHOSTUNREACH: 1954 case ENETDOWN: 1955 case EHOSTDOWN: 1956 default: 1957 type = ICMP_UNREACH; 1958 code = ICMP_UNREACH_HOST; 1959 break; 1960 1961 case EMSGSIZE: 1962 type = ICMP_UNREACH; 1963 code = ICMP_UNREACH_NEEDFRAG; 1964 1965 if ((rt = rtcache_validate(&ipforward_rt)) != NULL) { 1966 1967#if defined(IPSEC) || defined(FAST_IPSEC) 1968 /* 1969 * If the packet is routed over IPsec tunnel, tell the 1970 * originator the tunnel MTU. 1971 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1972 * XXX quickhack!!! 1973 */ 1974 1975 struct secpolicy *sp; 1976 int ipsecerror; 1977 size_t ipsechdr; 1978 struct route *ro; 1979 1980 sp = ipsec4_getpolicybyaddr(mcopy, 1981 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1982 &ipsecerror); 1983#endif 1984 1985 destmtu = rt->rt_ifp->if_mtu; 1986#if defined(IPSEC) || defined(FAST_IPSEC) 1987 if (sp != NULL) { 1988 /* count IPsec header size */ 1989 ipsechdr = ipsec4_hdrsiz(mcopy, 1990 IPSEC_DIR_OUTBOUND, NULL); 1991 1992 /* 1993 * find the correct route for outer IPv4 1994 * header, compute tunnel MTU. 1995 */ 1996 1997 if (sp->req != NULL 1998 && sp->req->sav != NULL 1999 && sp->req->sav->sah != NULL) { 2000 ro = &sp->req->sav->sah->sa_route; 2001 if (rt && rt->rt_ifp) { 2002 destmtu = 2003 rt->rt_rmx.rmx_mtu ? 2004 rt->rt_rmx.rmx_mtu : 2005 rt->rt_ifp->if_mtu; 2006 destmtu -= ipsechdr; 2007 } 2008 } 2009 2010#ifdef IPSEC 2011 key_freesp(sp); 2012#else 2013 KEY_FREESP(&sp); 2014#endif 2015 } 2016#endif /*defined(IPSEC) || defined(FAST_IPSEC)*/ 2017 } 2018 IP_STATINC(IP_STAT_CANTFRAG); 2019 break; 2020 2021 case ENOBUFS: 2022#if 1 2023 /* 2024 * a router should not generate ICMP_SOURCEQUENCH as 2025 * required in RFC1812 Requirements for IP Version 4 Routers. 2026 * source quench could be a big problem under DoS attacks, 2027 * or if the underlying interface is rate-limited. 2028 */ 2029 if (mcopy) 2030 m_freem(mcopy); 2031 return; 2032#else 2033 type = ICMP_SOURCEQUENCH; 2034 code = 0; 2035 break; 2036#endif 2037 } 2038 icmp_error(mcopy, type, code, dest, destmtu); 2039} 2040 2041void 2042ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 2043 struct mbuf *m) 2044{ 2045 2046 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 2047 struct timeval tv; 2048 2049 microtime(&tv); 2050 *mp = sbcreatecontrol((void *) &tv, sizeof(tv), 2051 SCM_TIMESTAMP, SOL_SOCKET); 2052 if (*mp) 2053 mp = &(*mp)->m_next; 2054 } 2055 if (inp->inp_flags & INP_RECVDSTADDR) { 2056 *mp = sbcreatecontrol((void *) &ip->ip_dst, 2057 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 2058 if (*mp) 2059 mp = &(*mp)->m_next; 2060 } 2061#ifdef notyet 2062 /* 2063 * XXX 2064 * Moving these out of udp_input() made them even more broken 2065 * than they already were. 2066 * - fenner@parc.xerox.com 2067 */ 2068 /* options were tossed already */ 2069 if (inp->inp_flags & INP_RECVOPTS) { 2070 *mp = sbcreatecontrol((void *) opts_deleted_above, 2071 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 2072 if (*mp) 2073 mp = &(*mp)->m_next; 2074 } 2075 /* ip_srcroute doesn't do what we want here, need to fix */ 2076 if (inp->inp_flags & INP_RECVRETOPTS) { 2077 *mp = sbcreatecontrol((void *) ip_srcroute(), 2078 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 2079 if (*mp) 2080 mp = &(*mp)->m_next; 2081 } 2082#endif 2083 if (inp->inp_flags & INP_RECVIF) { 2084 struct sockaddr_dl sdl; 2085 2086 sockaddr_dl_init(&sdl, sizeof(sdl), 2087 (m->m_pkthdr.rcvif != NULL) 2088 ? m->m_pkthdr.rcvif->if_index 2089 : 0, 2090 0, NULL, 0, NULL, 0); 2091 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP); 2092 if (*mp) 2093 mp = &(*mp)->m_next; 2094 } 2095} 2096 2097/* 2098 * sysctl helper routine for net.inet.ip.forwsrcrt. 2099 */ 2100static int 2101sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS) 2102{ 2103 int error, tmp; 2104 struct sysctlnode node; 2105 2106 node = *rnode; 2107 tmp = ip_forwsrcrt; 2108 node.sysctl_data = &tmp; 2109 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2110 if (error || newp == NULL) 2111 return (error); 2112 2113 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT, 2114 0, NULL, NULL, NULL)) 2115 return (EPERM); 2116 2117 ip_forwsrcrt = tmp; 2118 2119 return (0); 2120} 2121 2122/* 2123 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the 2124 * range of the new value and tweaks timers if it changes. 2125 */ 2126static int 2127sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS) 2128{ 2129 int error, tmp; 2130 struct sysctlnode node; 2131 2132 node = *rnode; 2133 tmp = ip_mtudisc_timeout; 2134 node.sysctl_data = &tmp; 2135 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2136 if (error || newp == NULL) 2137 return (error); 2138 if (tmp < 0) 2139 return (EINVAL); 2140 2141 ip_mtudisc_timeout = tmp; 2142 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 2143 2144 return (0); 2145} 2146 2147#ifdef GATEWAY 2148/* 2149 * sysctl helper routine for net.inet.ip.maxflows. 2150 */ 2151static int 2152sysctl_net_inet_ip_maxflows(SYSCTLFN_ARGS) 2153{ 2154 int s; 2155 2156 s = sysctl_lookup(SYSCTLFN_CALL(rnode)); 2157 if (s || newp == NULL) 2158 return (s); 2159 2160 s = splsoftnet(); 2161 ipflow_prune(); 2162 splx(s); 2163 2164 return (0); 2165} 2166 2167static int 2168sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS) 2169{ 2170 int error, tmp; 2171 struct sysctlnode node; 2172 2173 node = *rnode; 2174 tmp = ip_hashsize; 2175 node.sysctl_data = &tmp; 2176 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2177 if (error || newp == NULL) 2178 return (error); 2179 2180 if ((tmp & (tmp - 1)) == 0 && tmp != 0) { 2181 /* 2182 * Can only fail due to malloc() 2183 */ 2184 if (ipflow_invalidate_all(tmp)) 2185 return ENOMEM; 2186 } else { 2187 /* 2188 * EINVAL if not a power of 2 2189 */ 2190 return EINVAL; 2191 } 2192 2193 return (0); 2194} 2195#endif /* GATEWAY */ 2196 2197static void 2198ipstat_convert_to_user_cb(void *v1, void *v2, struct cpu_info *ci) 2199{ 2200 uint64_t *ipsc = v1; 2201 uint64_t *ips = v2; 2202 u_int i; 2203 2204 for (i = 0; i < IP_NSTATS; i++) 2205 ips[i] += ipsc[i]; 2206} 2207 2208static void 2209ipstat_convert_to_user(uint64_t *ips) 2210{ 2211 2212 memset(ips, 0, sizeof(uint64_t) * IP_NSTATS); 2213 percpu_foreach(ipstat_percpu, ipstat_convert_to_user_cb, ips); 2214} 2215 2216static int 2217sysctl_net_inet_ip_stats(SYSCTLFN_ARGS) 2218{ 2219 struct sysctlnode node; 2220 uint64_t ips[IP_NSTATS]; 2221 2222 ipstat_convert_to_user(ips); 2223 node = *rnode; 2224 node.sysctl_data = ips; 2225 node.sysctl_size = sizeof(ips); 2226 return (sysctl_lookup(SYSCTLFN_CALL(&node))); 2227} 2228 2229SYSCTL_SETUP(sysctl_net_inet_ip_setup, "sysctl net.inet.ip subtree setup") 2230{ 2231 extern int subnetsarelocal, hostzeroisbroadcast; 2232 2233 sysctl_createv(clog, 0, NULL, NULL, 2234 CTLFLAG_PERMANENT, 2235 CTLTYPE_NODE, "net", NULL, 2236 NULL, 0, NULL, 0, 2237 CTL_NET, CTL_EOL); 2238 sysctl_createv(clog, 0, NULL, NULL, 2239 CTLFLAG_PERMANENT, 2240 CTLTYPE_NODE, "inet", 2241 SYSCTL_DESCR("PF_INET related settings"), 2242 NULL, 0, NULL, 0, 2243 CTL_NET, PF_INET, CTL_EOL); 2244 sysctl_createv(clog, 0, NULL, NULL, 2245 CTLFLAG_PERMANENT, 2246 CTLTYPE_NODE, "ip", 2247 SYSCTL_DESCR("IPv4 related settings"), 2248 NULL, 0, NULL, 0, 2249 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL); 2250 2251 sysctl_createv(clog, 0, NULL, NULL, 2252 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2253 CTLTYPE_INT, "forwarding", 2254 SYSCTL_DESCR("Enable forwarding of INET datagrams"), 2255 NULL, 0, &ipforwarding, 0, 2256 CTL_NET, PF_INET, IPPROTO_IP, 2257 IPCTL_FORWARDING, CTL_EOL); 2258 sysctl_createv(clog, 0, NULL, NULL, 2259 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2260 CTLTYPE_INT, "redirect", 2261 SYSCTL_DESCR("Enable sending of ICMP redirect messages"), 2262 NULL, 0, &ipsendredirects, 0, 2263 CTL_NET, PF_INET, IPPROTO_IP, 2264 IPCTL_SENDREDIRECTS, CTL_EOL); 2265 sysctl_createv(clog, 0, NULL, NULL, 2266 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2267 CTLTYPE_INT, "ttl", 2268 SYSCTL_DESCR("Default TTL for an INET datagram"), 2269 NULL, 0, &ip_defttl, 0, 2270 CTL_NET, PF_INET, IPPROTO_IP, 2271 IPCTL_DEFTTL, CTL_EOL); 2272#ifdef IPCTL_DEFMTU 2273 sysctl_createv(clog, 0, NULL, NULL, 2274 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */, 2275 CTLTYPE_INT, "mtu", 2276 SYSCTL_DESCR("Default MTA for an INET route"), 2277 NULL, 0, &ip_mtu, 0, 2278 CTL_NET, PF_INET, IPPROTO_IP, 2279 IPCTL_DEFMTU, CTL_EOL); 2280#endif /* IPCTL_DEFMTU */ 2281 sysctl_createv(clog, 0, NULL, NULL, 2282 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2283 CTLTYPE_INT, "forwsrcrt", 2284 SYSCTL_DESCR("Enable forwarding of source-routed " 2285 "datagrams"), 2286 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0, 2287 CTL_NET, PF_INET, IPPROTO_IP, 2288 IPCTL_FORWSRCRT, CTL_EOL); 2289 sysctl_createv(clog, 0, NULL, NULL, 2290 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2291 CTLTYPE_INT, "directed-broadcast", 2292 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"), 2293 NULL, 0, &ip_directedbcast, 0, 2294 CTL_NET, PF_INET, IPPROTO_IP, 2295 IPCTL_DIRECTEDBCAST, CTL_EOL); 2296 sysctl_createv(clog, 0, NULL, NULL, 2297 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2298 CTLTYPE_INT, "allowsrcrt", 2299 SYSCTL_DESCR("Accept source-routed datagrams"), 2300 NULL, 0, &ip_allowsrcrt, 0, 2301 CTL_NET, PF_INET, IPPROTO_IP, 2302 IPCTL_ALLOWSRCRT, CTL_EOL); 2303 sysctl_createv(clog, 0, NULL, NULL, 2304 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2305 CTLTYPE_INT, "subnetsarelocal", 2306 SYSCTL_DESCR("Whether logical subnets are considered " 2307 "local"), 2308 NULL, 0, &subnetsarelocal, 0, 2309 CTL_NET, PF_INET, IPPROTO_IP, 2310 IPCTL_SUBNETSARELOCAL, CTL_EOL); 2311 sysctl_createv(clog, 0, NULL, NULL, 2312 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2313 CTLTYPE_INT, "mtudisc", 2314 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"), 2315 NULL, 0, &ip_mtudisc, 0, 2316 CTL_NET, PF_INET, IPPROTO_IP, 2317 IPCTL_MTUDISC, CTL_EOL); 2318 sysctl_createv(clog, 0, NULL, NULL, 2319 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2320 CTLTYPE_INT, "anonportmin", 2321 SYSCTL_DESCR("Lowest ephemeral port number to assign"), 2322 sysctl_net_inet_ip_ports, 0, &anonportmin, 0, 2323 CTL_NET, PF_INET, IPPROTO_IP, 2324 IPCTL_ANONPORTMIN, CTL_EOL); 2325 sysctl_createv(clog, 0, NULL, NULL, 2326 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2327 CTLTYPE_INT, "anonportmax", 2328 SYSCTL_DESCR("Highest ephemeral port number to assign"), 2329 sysctl_net_inet_ip_ports, 0, &anonportmax, 0, 2330 CTL_NET, PF_INET, IPPROTO_IP, 2331 IPCTL_ANONPORTMAX, CTL_EOL); 2332 sysctl_createv(clog, 0, NULL, NULL, 2333 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2334 CTLTYPE_INT, "mtudisctimeout", 2335 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"), 2336 sysctl_net_inet_ip_pmtudto, 0, &ip_mtudisc_timeout, 0, 2337 CTL_NET, PF_INET, IPPROTO_IP, 2338 IPCTL_MTUDISCTIMEOUT, CTL_EOL); 2339#ifdef GATEWAY 2340 sysctl_createv(clog, 0, NULL, NULL, 2341 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2342 CTLTYPE_INT, "maxflows", 2343 SYSCTL_DESCR("Number of flows for fast forwarding"), 2344 sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0, 2345 CTL_NET, PF_INET, IPPROTO_IP, 2346 IPCTL_MAXFLOWS, CTL_EOL); 2347 sysctl_createv(clog, 0, NULL, NULL, 2348 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2349 CTLTYPE_INT, "hashsize", 2350 SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"), 2351 sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0, 2352 CTL_NET, PF_INET, IPPROTO_IP, 2353 CTL_CREATE, CTL_EOL); 2354#endif /* GATEWAY */ 2355 sysctl_createv(clog, 0, NULL, NULL, 2356 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2357 CTLTYPE_INT, "hostzerobroadcast", 2358 SYSCTL_DESCR("All zeroes address is broadcast address"), 2359 NULL, 0, &hostzeroisbroadcast, 0, 2360 CTL_NET, PF_INET, IPPROTO_IP, 2361 IPCTL_HOSTZEROBROADCAST, CTL_EOL); 2362#if NGIF > 0 2363 sysctl_createv(clog, 0, NULL, NULL, 2364 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2365 CTLTYPE_INT, "gifttl", 2366 SYSCTL_DESCR("Default TTL for a gif tunnel datagram"), 2367 NULL, 0, &ip_gif_ttl, 0, 2368 CTL_NET, PF_INET, IPPROTO_IP, 2369 IPCTL_GIF_TTL, CTL_EOL); 2370#endif /* NGIF */ 2371#ifndef IPNOPRIVPORTS 2372 sysctl_createv(clog, 0, NULL, NULL, 2373 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2374 CTLTYPE_INT, "lowportmin", 2375 SYSCTL_DESCR("Lowest privileged ephemeral port number " 2376 "to assign"), 2377 sysctl_net_inet_ip_ports, 0, &lowportmin, 0, 2378 CTL_NET, PF_INET, IPPROTO_IP, 2379 IPCTL_LOWPORTMIN, CTL_EOL); 2380 sysctl_createv(clog, 0, NULL, NULL, 2381 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2382 CTLTYPE_INT, "lowportmax", 2383 SYSCTL_DESCR("Highest privileged ephemeral port number " 2384 "to assign"), 2385 sysctl_net_inet_ip_ports, 0, &lowportmax, 0, 2386 CTL_NET, PF_INET, IPPROTO_IP, 2387 IPCTL_LOWPORTMAX, CTL_EOL); 2388#endif /* IPNOPRIVPORTS */ 2389 sysctl_createv(clog, 0, NULL, NULL, 2390 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2391 CTLTYPE_INT, "maxfragpackets", 2392 SYSCTL_DESCR("Maximum number of fragments to retain for " 2393 "possible reassembly"), 2394 NULL, 0, &ip_maxfragpackets, 0, 2395 CTL_NET, PF_INET, IPPROTO_IP, 2396 IPCTL_MAXFRAGPACKETS, CTL_EOL); 2397#if NGRE > 0 2398 sysctl_createv(clog, 0, NULL, NULL, 2399 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2400 CTLTYPE_INT, "grettl", 2401 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"), 2402 NULL, 0, &ip_gre_ttl, 0, 2403 CTL_NET, PF_INET, IPPROTO_IP, 2404 IPCTL_GRE_TTL, CTL_EOL); 2405#endif /* NGRE */ 2406 sysctl_createv(clog, 0, NULL, NULL, 2407 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2408 CTLTYPE_INT, "checkinterface", 2409 SYSCTL_DESCR("Enable receive side of Strong ES model " 2410 "from RFC1122"), 2411 NULL, 0, &ip_checkinterface, 0, 2412 CTL_NET, PF_INET, IPPROTO_IP, 2413 IPCTL_CHECKINTERFACE, CTL_EOL); 2414 sysctl_createv(clog, 0, NULL, NULL, 2415 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2416 CTLTYPE_INT, "random_id", 2417 SYSCTL_DESCR("Assign random ip_id values"), 2418 NULL, 0, &ip_do_randomid, 0, 2419 CTL_NET, PF_INET, IPPROTO_IP, 2420 IPCTL_RANDOMID, CTL_EOL); 2421 sysctl_createv(clog, 0, NULL, NULL, 2422 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2423 CTLTYPE_INT, "do_loopback_cksum", 2424 SYSCTL_DESCR("Perform IP checksum on loopback"), 2425 NULL, 0, &ip_do_loopback_cksum, 0, 2426 CTL_NET, PF_INET, IPPROTO_IP, 2427 IPCTL_LOOPBACKCKSUM, CTL_EOL); 2428 sysctl_createv(clog, 0, NULL, NULL, 2429 CTLFLAG_PERMANENT, 2430 CTLTYPE_STRUCT, "stats", 2431 SYSCTL_DESCR("IP statistics"), 2432 sysctl_net_inet_ip_stats, 0, NULL, 0, 2433 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS, 2434 CTL_EOL); 2435} 2436 2437void 2438ip_statinc(u_int stat) 2439{ 2440 2441 KASSERT(stat < IP_NSTATS); 2442 IP_STATINC(stat); 2443} 2444