ip_input.c revision 1.268
1/* $NetBSD: ip_input.c,v 1.268 2008/04/24 11:38:37 ad 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 1.268 2008/04/24 11:38:37 ad 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 <netinet6/ipsec_private.h> 153#include <netkey/key.h> 154#endif 155#ifdef FAST_IPSEC 156#include <netipsec/ipsec.h> 157#include <netipsec/key.h> 158#endif /* FAST_IPSEC*/ 159 160#ifndef IPFORWARDING 161#ifdef GATEWAY 162#define IPFORWARDING 1 /* forward IP packets not for us */ 163#else /* GATEWAY */ 164#define IPFORWARDING 0 /* don't forward IP packets not for us */ 165#endif /* GATEWAY */ 166#endif /* IPFORWARDING */ 167#ifndef IPSENDREDIRECTS 168#define IPSENDREDIRECTS 1 169#endif 170#ifndef IPFORWSRCRT 171#define IPFORWSRCRT 1 /* forward source-routed packets */ 172#endif 173#ifndef IPALLOWSRCRT 174#define IPALLOWSRCRT 1 /* allow source-routed packets */ 175#endif 176#ifndef IPMTUDISC 177#define IPMTUDISC 1 178#endif 179#ifndef IPMTUDISCTIMEOUT 180#define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 181#endif 182 183/* 184 * Note: DIRECTED_BROADCAST is handled this way so that previous 185 * configuration using this option will Just Work. 186 */ 187#ifndef IPDIRECTEDBCAST 188#ifdef DIRECTED_BROADCAST 189#define IPDIRECTEDBCAST 1 190#else 191#define IPDIRECTEDBCAST 0 192#endif /* DIRECTED_BROADCAST */ 193#endif /* IPDIRECTEDBCAST */ 194int ipforwarding = IPFORWARDING; 195int ipsendredirects = IPSENDREDIRECTS; 196int ip_defttl = IPDEFTTL; 197int ip_forwsrcrt = IPFORWSRCRT; 198int ip_directedbcast = IPDIRECTEDBCAST; 199int ip_allowsrcrt = IPALLOWSRCRT; 200int ip_mtudisc = IPMTUDISC; 201int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 202#ifdef DIAGNOSTIC 203int ipprintfs = 0; 204#endif 205 206int ip_do_randomid = 0; 207 208/* 209 * XXX - Setting ip_checkinterface mostly implements the receive side of 210 * the Strong ES model described in RFC 1122, but since the routing table 211 * and transmit implementation do not implement the Strong ES model, 212 * setting this to 1 results in an odd hybrid. 213 * 214 * XXX - ip_checkinterface currently must be disabled if you use ipnat 215 * to translate the destination address to another local interface. 216 * 217 * XXX - ip_checkinterface must be disabled if you add IP aliases 218 * to the loopback interface instead of the interface where the 219 * packets for those addresses are received. 220 */ 221int ip_checkinterface = 0; 222 223 224struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 225 226int ipqmaxlen = IFQ_MAXLEN; 227u_long in_ifaddrhash; /* size of hash table - 1 */ 228int in_ifaddrentries; /* total number of addrs */ 229struct in_ifaddrhead in_ifaddrhead; 230struct in_ifaddrhashhead *in_ifaddrhashtbl; 231u_long in_multihash; /* size of hash table - 1 */ 232int in_multientries; /* total number of addrs */ 233struct in_multihashhead *in_multihashtbl; 234struct ifqueue ipintrq; 235uint16_t ip_id; 236 237percpu_t *ipstat_percpu; 238 239#ifdef PFIL_HOOKS 240struct pfil_head inet_pfil_hook; 241#endif 242 243/* 244 * Cached copy of nmbclusters. If nbclusters is different, 245 * recalculate IP parameters derived from nmbclusters. 246 */ 247static int ip_nmbclusters; /* copy of nmbclusters */ 248static void ip_nmbclusters_changed(void); /* recalc limits */ 249 250#define CHECK_NMBCLUSTER_PARAMS() \ 251do { \ 252 if (__predict_false(ip_nmbclusters != nmbclusters)) \ 253 ip_nmbclusters_changed(); \ 254} while (/*CONSTCOND*/0) 255 256/* IP datagram reassembly queues (hashed) */ 257#define IPREASS_NHASH_LOG2 6 258#define IPREASS_NHASH (1 << IPREASS_NHASH_LOG2) 259#define IPREASS_HMASK (IPREASS_NHASH - 1) 260#define IPREASS_HASH(x,y) \ 261 (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK) 262struct ipqhead ipq[IPREASS_NHASH]; 263int ipq_locked; 264static int ip_nfragpackets; /* packets in reass queue */ 265static int ip_nfrags; /* total fragments in reass queues */ 266 267int ip_maxfragpackets = 200; /* limit on packets. XXX sysctl */ 268int ip_maxfrags; /* limit on fragments. XXX sysctl */ 269 270 271/* 272 * Additive-Increase/Multiplicative-Decrease (AIMD) strategy for 273 * IP reassembly queue buffer managment. 274 * 275 * We keep a count of total IP fragments (NB: not fragmented packets!) 276 * awaiting reassembly (ip_nfrags) and a limit (ip_maxfrags) on fragments. 277 * If ip_nfrags exceeds ip_maxfrags the limit, we drop half the 278 * total fragments in reassembly queues.This AIMD policy avoids 279 * repeatedly deleting single packets under heavy fragmentation load 280 * (e.g., from lossy NFS peers). 281 */ 282static u_int ip_reass_ttl_decr(u_int ticks); 283static void ip_reass_drophalf(void); 284 285 286static inline int ipq_lock_try(void); 287static inline void ipq_unlock(void); 288 289static inline int 290ipq_lock_try(void) 291{ 292 int s; 293 294 /* 295 * Use splvm() -- we're blocking things that would cause 296 * mbuf allocation. 297 */ 298 s = splvm(); 299 if (ipq_locked) { 300 splx(s); 301 return (0); 302 } 303 ipq_locked = 1; 304 splx(s); 305 return (1); 306} 307 308static inline void 309ipq_unlock(void) 310{ 311 int s; 312 313 s = splvm(); 314 ipq_locked = 0; 315 splx(s); 316} 317 318#ifdef DIAGNOSTIC 319#define IPQ_LOCK() \ 320do { \ 321 if (ipq_lock_try() == 0) { \ 322 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 323 panic("ipq_lock"); \ 324 } \ 325} while (/*CONSTCOND*/ 0) 326#define IPQ_LOCK_CHECK() \ 327do { \ 328 if (ipq_locked == 0) { \ 329 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 330 panic("ipq lock check"); \ 331 } \ 332} while (/*CONSTCOND*/ 0) 333#else 334#define IPQ_LOCK() (void) ipq_lock_try() 335#define IPQ_LOCK_CHECK() /* nothing */ 336#endif 337 338#define IPQ_UNLOCK() ipq_unlock() 339 340POOL_INIT(inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", NULL, 341 IPL_SOFTNET); 342POOL_INIT(ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", NULL, 343 IPL_VM); 344 345#ifdef INET_CSUM_COUNTERS 346#include <sys/device.h> 347 348struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 349 NULL, "inet", "hwcsum bad"); 350struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 351 NULL, "inet", "hwcsum ok"); 352struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 353 NULL, "inet", "swcsum"); 354 355#define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 356 357EVCNT_ATTACH_STATIC(ip_hwcsum_bad); 358EVCNT_ATTACH_STATIC(ip_hwcsum_ok); 359EVCNT_ATTACH_STATIC(ip_swcsum); 360 361#else 362 363#define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 364 365#endif /* INET_CSUM_COUNTERS */ 366 367/* 368 * We need to save the IP options in case a protocol wants to respond 369 * to an incoming packet over the same route if the packet got here 370 * using IP source routing. This allows connection establishment and 371 * maintenance when the remote end is on a network that is not known 372 * to us. 373 */ 374int ip_nhops = 0; 375static struct ip_srcrt { 376 struct in_addr dst; /* final destination */ 377 char nop; /* one NOP to align */ 378 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 379 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 380} ip_srcrt; 381 382static void save_rte(u_char *, struct in_addr); 383 384#ifdef MBUFTRACE 385struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx"); 386struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx"); 387#endif 388 389/* 390 * Compute IP limits derived from the value of nmbclusters. 391 */ 392static void 393ip_nmbclusters_changed(void) 394{ 395 ip_maxfrags = nmbclusters / 4; 396 ip_nmbclusters = nmbclusters; 397} 398 399/* 400 * IP initialization: fill in IP protocol switch table. 401 * All protocols not implemented in kernel go to raw IP protocol handler. 402 */ 403void 404ip_init(void) 405{ 406 const struct protosw *pr; 407 int i; 408 409 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 410 if (pr == 0) 411 panic("ip_init"); 412 for (i = 0; i < IPPROTO_MAX; i++) 413 ip_protox[i] = pr - inetsw; 414 for (pr = inetdomain.dom_protosw; 415 pr < inetdomain.dom_protoswNPROTOSW; pr++) 416 if (pr->pr_domain->dom_family == PF_INET && 417 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 418 ip_protox[pr->pr_protocol] = pr - inetsw; 419 420 for (i = 0; i < IPREASS_NHASH; i++) 421 LIST_INIT(&ipq[i]); 422 423 ip_initid(); 424 ip_id = time_second & 0xfffff; 425 426 ipintrq.ifq_maxlen = ipqmaxlen; 427 ip_nmbclusters_changed(); 428 429 TAILQ_INIT(&in_ifaddrhead); 430 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR, 431 M_WAITOK, &in_ifaddrhash); 432 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IPMADDR, 433 M_WAITOK, &in_multihash); 434 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 435#ifdef GATEWAY 436 ipflow_init(ip_hashsize); 437#endif 438 439#ifdef PFIL_HOOKS 440 /* Register our Packet Filter hook. */ 441 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 442 inet_pfil_hook.ph_af = AF_INET; 443 i = pfil_head_register(&inet_pfil_hook); 444 if (i != 0) 445 printf("ip_init: WARNING: unable to register pfil hook, " 446 "error %d\n", i); 447#endif /* PFIL_HOOKS */ 448 449#ifdef MBUFTRACE 450 MOWNER_ATTACH(&ip_tx_mowner); 451 MOWNER_ATTACH(&ip_rx_mowner); 452#endif /* MBUFTRACE */ 453 454 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS); 455} 456 457struct sockaddr_in ipaddr = { 458 .sin_len = sizeof(ipaddr), 459 .sin_family = AF_INET, 460}; 461struct route ipforward_rt; 462 463/* 464 * IP software interrupt routine 465 */ 466void 467ipintr(void) 468{ 469 int s; 470 struct mbuf *m; 471 472 mutex_enter(softnet_lock); 473 KERNEL_LOCK(1, NULL); 474 while (!IF_IS_EMPTY(&ipintrq)) { 475 s = splnet(); 476 IF_DEQUEUE(&ipintrq, m); 477 splx(s); 478 if (m == NULL) 479 break; 480 ip_input(m); 481 } 482 KERNEL_UNLOCK_ONE(NULL); 483 mutex_exit(softnet_lock); 484} 485 486/* 487 * Ip input routine. Checksum and byte swap header. If fragmented 488 * try to reassemble. Process options. Pass to next level. 489 */ 490void 491ip_input(struct mbuf *m) 492{ 493 struct ip *ip = NULL; 494 struct ipq *fp; 495 struct in_ifaddr *ia; 496 struct ifaddr *ifa; 497 struct ipqent *ipqe; 498 int hlen = 0, mff, len; 499 int downmatch; 500 int checkif; 501 int srcrt = 0; 502 int s; 503 u_int hash; 504#ifdef FAST_IPSEC 505 struct m_tag *mtag; 506 struct tdb_ident *tdbi; 507 struct secpolicy *sp; 508 int error; 509#endif /* FAST_IPSEC */ 510 511 MCLAIM(m, &ip_rx_mowner); 512#ifdef DIAGNOSTIC 513 if ((m->m_flags & M_PKTHDR) == 0) 514 panic("ipintr no HDR"); 515#endif 516 517 /* 518 * If no IP addresses have been set yet but the interfaces 519 * are receiving, can't do anything with incoming packets yet. 520 */ 521 if (TAILQ_FIRST(&in_ifaddrhead) == 0) 522 goto bad; 523 IP_STATINC(IP_STAT_TOTAL); 524 /* 525 * If the IP header is not aligned, slurp it up into a new 526 * mbuf with space for link headers, in the event we forward 527 * it. Otherwise, if it is aligned, make sure the entire 528 * base IP header is in the first mbuf of the chain. 529 */ 530 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) { 531 if ((m = m_copyup(m, sizeof(struct ip), 532 (max_linkhdr + 3) & ~3)) == NULL) { 533 /* XXXJRT new stat, please */ 534 IP_STATINC(IP_STAT_TOOSMALL); 535 return; 536 } 537 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 538 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 539 IP_STATINC(IP_STAT_TOOSMALL); 540 return; 541 } 542 } 543 ip = mtod(m, struct ip *); 544 if (ip->ip_v != IPVERSION) { 545 IP_STATINC(IP_STAT_BADVERS); 546 goto bad; 547 } 548 hlen = ip->ip_hl << 2; 549 if (hlen < sizeof(struct ip)) { /* minimum header length */ 550 IP_STATINC(IP_STAT_BADHLEN); 551 goto bad; 552 } 553 if (hlen > m->m_len) { 554 if ((m = m_pullup(m, hlen)) == 0) { 555 IP_STATINC(IP_STAT_BADHLEN); 556 return; 557 } 558 ip = mtod(m, struct ip *); 559 } 560 561 /* 562 * RFC1122: packets with a multicast source address are 563 * not allowed. 564 */ 565 if (IN_MULTICAST(ip->ip_src.s_addr)) { 566 IP_STATINC(IP_STAT_BADADDR); 567 goto bad; 568 } 569 570 /* 127/8 must not appear on wire - RFC1122 */ 571 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 572 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 573 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 574 IP_STATINC(IP_STAT_BADADDR); 575 goto bad; 576 } 577 } 578 579 switch (m->m_pkthdr.csum_flags & 580 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 581 M_CSUM_IPv4_BAD)) { 582 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 583 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 584 goto badcsum; 585 586 case M_CSUM_IPv4: 587 /* Checksum was okay. */ 588 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 589 break; 590 591 default: 592 /* 593 * Must compute it ourselves. Maybe skip checksum on 594 * loopback interfaces. 595 */ 596 if (__predict_true(!(m->m_pkthdr.rcvif->if_flags & 597 IFF_LOOPBACK) || ip_do_loopback_cksum)) { 598 INET_CSUM_COUNTER_INCR(&ip_swcsum); 599 if (in_cksum(m, hlen) != 0) 600 goto badcsum; 601 } 602 break; 603 } 604 605 /* Retrieve the packet length. */ 606 len = ntohs(ip->ip_len); 607 608 /* 609 * Check for additional length bogosity 610 */ 611 if (len < hlen) { 612 IP_STATINC(IP_STAT_BADLEN); 613 goto bad; 614 } 615 616 /* 617 * Check that the amount of data in the buffers 618 * is as at least much as the IP header would have us expect. 619 * Trim mbufs if longer than we expect. 620 * Drop packet if shorter than we expect. 621 */ 622 if (m->m_pkthdr.len < len) { 623 IP_STATINC(IP_STAT_TOOSHORT); 624 goto bad; 625 } 626 if (m->m_pkthdr.len > len) { 627 if (m->m_len == m->m_pkthdr.len) { 628 m->m_len = len; 629 m->m_pkthdr.len = len; 630 } else 631 m_adj(m, len - m->m_pkthdr.len); 632 } 633 634#if defined(IPSEC) 635 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 636 m->m_flags &= ~M_CANFASTFWD; 637#else 638 /* 639 * Assume that we can create a fast-forward IP flow entry 640 * based on this packet. 641 */ 642 m->m_flags |= M_CANFASTFWD; 643#endif 644 645#ifdef PFIL_HOOKS 646 /* 647 * Run through list of hooks for input packets. If there are any 648 * filters which require that additional packets in the flow are 649 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 650 * Note that filters must _never_ set this flag, as another filter 651 * in the list may have previously cleared it. 652 */ 653 /* 654 * let ipfilter look at packet on the wire, 655 * not the decapsulated packet. 656 */ 657#ifdef IPSEC 658 if (!ipsec_getnhist(m)) 659#elif defined(FAST_IPSEC) 660 if (!ipsec_indone(m)) 661#else 662 if (1) 663#endif 664 { 665 struct in_addr odst; 666 667 odst = ip->ip_dst; 668 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 669 PFIL_IN) != 0) 670 return; 671 if (m == NULL) 672 return; 673 ip = mtod(m, struct ip *); 674 hlen = ip->ip_hl << 2; 675 /* 676 * XXX The setting of "srcrt" here is to prevent ip_forward() 677 * from generating ICMP redirects for packets that have 678 * been redirected by a hook back out on to the same LAN that 679 * they came from and is not an indication that the packet 680 * is being inffluenced by source routing options. This 681 * allows things like 682 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp" 683 * where tlp0 is both on the 1.1.1.0/24 network and is the 684 * default route for hosts on 1.1.1.0/24. Of course this 685 * also requires a "map tlp0 ..." to complete the story. 686 * One might argue whether or not this kind of network config. 687 * should be supported in this manner... 688 */ 689 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 690 } 691#endif /* PFIL_HOOKS */ 692 693#ifdef ALTQ 694 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 695 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 696 /* packet dropped by traffic conditioner */ 697 return; 698 } 699#endif 700 701 /* 702 * Process options and, if not destined for us, 703 * ship it on. ip_dooptions returns 1 when an 704 * error was detected (causing an icmp message 705 * to be sent and the original packet to be freed). 706 */ 707 ip_nhops = 0; /* for source routed packets */ 708 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 709 return; 710 711 /* 712 * Enable a consistency check between the destination address 713 * and the arrival interface for a unicast packet (the RFC 1122 714 * strong ES model) if IP forwarding is disabled and the packet 715 * is not locally generated. 716 * 717 * XXX - Checking also should be disabled if the destination 718 * address is ipnat'ed to a different interface. 719 * 720 * XXX - Checking is incompatible with IP aliases added 721 * to the loopback interface instead of the interface where 722 * the packets are received. 723 * 724 * XXX - We need to add a per ifaddr flag for this so that 725 * we get finer grain control. 726 */ 727 checkif = ip_checkinterface && (ipforwarding == 0) && 728 (m->m_pkthdr.rcvif != NULL) && 729 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 730 731 /* 732 * Check our list of addresses, to see if the packet is for us. 733 * 734 * Traditional 4.4BSD did not consult IFF_UP at all. 735 * The behavior here is to treat addresses on !IFF_UP interface 736 * as not mine. 737 */ 738 downmatch = 0; 739 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 740 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 741 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 742 continue; 743 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 744 break; 745 else 746 downmatch++; 747 } 748 } 749 if (ia != NULL) 750 goto ours; 751 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 752 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 753 if (ifa->ifa_addr->sa_family != AF_INET) 754 continue; 755 ia = ifatoia(ifa); 756 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 757 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 758 /* 759 * Look for all-0's host part (old broadcast addr), 760 * either for subnet or net. 761 */ 762 ip->ip_dst.s_addr == ia->ia_subnet || 763 ip->ip_dst.s_addr == ia->ia_net) 764 goto ours; 765 /* 766 * An interface with IP address zero accepts 767 * all packets that arrive on that interface. 768 */ 769 if (in_nullhost(ia->ia_addr.sin_addr)) 770 goto ours; 771 } 772 } 773 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 774 struct in_multi *inm; 775#ifdef MROUTING 776 extern struct socket *ip_mrouter; 777 778 if (ip_mrouter) { 779 /* 780 * If we are acting as a multicast router, all 781 * incoming multicast packets are passed to the 782 * kernel-level multicast forwarding function. 783 * The packet is returned (relatively) intact; if 784 * ip_mforward() returns a non-zero value, the packet 785 * must be discarded, else it may be accepted below. 786 * 787 * (The IP ident field is put in the same byte order 788 * as expected when ip_mforward() is called from 789 * ip_output().) 790 */ 791 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 792 IP_STATINC(IP_STAT_CANTFORWARD); 793 m_freem(m); 794 return; 795 } 796 797 /* 798 * The process-level routing demon needs to receive 799 * all multicast IGMP packets, whether or not this 800 * host belongs to their destination groups. 801 */ 802 if (ip->ip_p == IPPROTO_IGMP) 803 goto ours; 804 IP_STATINC(IP_STAT_CANTFORWARD); 805 } 806#endif 807 /* 808 * See if we belong to the destination multicast group on the 809 * arrival interface. 810 */ 811 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 812 if (inm == NULL) { 813 IP_STATINC(IP_STAT_CANTFORWARD); 814 m_freem(m); 815 return; 816 } 817 goto ours; 818 } 819 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 820 in_nullhost(ip->ip_dst)) 821 goto ours; 822 823 /* 824 * Not for us; forward if possible and desirable. 825 */ 826 if (ipforwarding == 0) { 827 IP_STATINC(IP_STAT_CANTFORWARD); 828 m_freem(m); 829 } else { 830 /* 831 * If ip_dst matched any of my address on !IFF_UP interface, 832 * and there's no IFF_UP interface that matches ip_dst, 833 * send icmp unreach. Forwarding it will result in in-kernel 834 * forwarding loop till TTL goes to 0. 835 */ 836 if (downmatch) { 837 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 838 IP_STATINC(IP_STAT_CANTFORWARD); 839 return; 840 } 841#ifdef IPSEC 842 if (ipsec4_in_reject(m, NULL)) { 843 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 844 goto bad; 845 } 846#endif 847#ifdef FAST_IPSEC 848 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 849 s = splsoftnet(); 850 if (mtag != NULL) { 851 tdbi = (struct tdb_ident *)(mtag + 1); 852 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 853 } else { 854 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 855 IP_FORWARDING, &error); 856 } 857 if (sp == NULL) { /* NB: can happen if error */ 858 splx(s); 859 /*XXX error stat???*/ 860 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/ 861 goto bad; 862 } 863 864 /* 865 * Check security policy against packet attributes. 866 */ 867 error = ipsec_in_reject(sp, m); 868 KEY_FREESP(&sp); 869 splx(s); 870 if (error) { 871 IP_STATINC(IP_STAT_CANTFORWARD); 872 goto bad; 873 } 874 875 /* 876 * Peek at the outbound SP for this packet to determine if 877 * it's a Fast Forward candidate. 878 */ 879 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 880 if (mtag != NULL) 881 m->m_flags &= ~M_CANFASTFWD; 882 else { 883 s = splsoftnet(); 884 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, 885 (IP_FORWARDING | 886 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 887 &error, NULL); 888 if (sp != NULL) { 889 m->m_flags &= ~M_CANFASTFWD; 890 KEY_FREESP(&sp); 891 } 892 splx(s); 893 } 894#endif /* FAST_IPSEC */ 895 896 ip_forward(m, srcrt); 897 } 898 return; 899 900ours: 901 /* 902 * If offset or IP_MF are set, must reassemble. 903 * Otherwise, nothing need be done. 904 * (We could look in the reassembly queue to see 905 * if the packet was previously fragmented, 906 * but it's not worth the time; just let them time out.) 907 */ 908 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 909 uint16_t off; 910 /* 911 * Prevent TCP blind data attacks by not allowing non-initial 912 * fragments to start at less than 68 bytes (minimal fragment 913 * size) and making sure the first fragment is at least 68 914 * bytes. 915 */ 916 off = (ntohs(ip->ip_off) & IP_OFFMASK) << 3; 917 if ((off > 0 ? off + hlen : len) < IP_MINFRAGSIZE - 1) { 918 IP_STATINC(IP_STAT_BADFRAGS); 919 goto bad; 920 } 921 /* 922 * Look for queue of fragments 923 * of this datagram. 924 */ 925 IPQ_LOCK(); 926 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id); 927 LIST_FOREACH(fp, &ipq[hash], ipq_q) { 928 if (ip->ip_id == fp->ipq_id && 929 in_hosteq(ip->ip_src, fp->ipq_src) && 930 in_hosteq(ip->ip_dst, fp->ipq_dst) && 931 ip->ip_p == fp->ipq_p) { 932 /* 933 * Make sure the TOS is matches previous 934 * fragments. 935 */ 936 if (ip->ip_tos != fp->ipq_tos) { 937 IP_STATINC(IP_STAT_BADFRAGS); 938 goto bad; 939 } 940 goto found; 941 } 942 } 943 fp = 0; 944found: 945 946 /* 947 * Adjust ip_len to not reflect header, 948 * set ipqe_mff if more fragments are expected, 949 * convert offset of this to bytes. 950 */ 951 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 952 mff = (ip->ip_off & htons(IP_MF)) != 0; 953 if (mff) { 954 /* 955 * Make sure that fragments have a data length 956 * that's a non-zero multiple of 8 bytes. 957 */ 958 if (ntohs(ip->ip_len) == 0 || 959 (ntohs(ip->ip_len) & 0x7) != 0) { 960 IP_STATINC(IP_STAT_BADFRAGS); 961 IPQ_UNLOCK(); 962 goto bad; 963 } 964 } 965 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 966 967 /* 968 * If datagram marked as having more fragments 969 * or if this is not the first fragment, 970 * attempt reassembly; if it succeeds, proceed. 971 */ 972 if (mff || ip->ip_off != htons(0)) { 973 IP_STATINC(IP_STAT_FRAGMENTS); 974 s = splvm(); 975 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 976 splx(s); 977 if (ipqe == NULL) { 978 IP_STATINC(IP_STAT_RCVMEMDROP); 979 IPQ_UNLOCK(); 980 goto bad; 981 } 982 ipqe->ipqe_mff = mff; 983 ipqe->ipqe_m = m; 984 ipqe->ipqe_ip = ip; 985 m = ip_reass(ipqe, fp, &ipq[hash]); 986 if (m == 0) { 987 IPQ_UNLOCK(); 988 return; 989 } 990 IP_STATINC(IP_STAT_REASSEMBLED); 991 ip = mtod(m, struct ip *); 992 hlen = ip->ip_hl << 2; 993 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 994 } else 995 if (fp) 996 ip_freef(fp); 997 IPQ_UNLOCK(); 998 } 999 1000#if defined(IPSEC) 1001 /* 1002 * enforce IPsec policy checking if we are seeing last header. 1003 * note that we do not visit this with protocols with pcb layer 1004 * code - like udp/tcp/raw ip. 1005 */ 1006 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 1007 ipsec4_in_reject(m, NULL)) { 1008 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1009 goto bad; 1010 } 1011#endif 1012#ifdef FAST_IPSEC 1013 /* 1014 * enforce IPsec policy checking if we are seeing last header. 1015 * note that we do not visit this with protocols with pcb layer 1016 * code - like udp/tcp/raw ip. 1017 */ 1018 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 1019 /* 1020 * Check if the packet has already had IPsec processing 1021 * done. If so, then just pass it along. This tag gets 1022 * set during AH, ESP, etc. input handling, before the 1023 * packet is returned to the ip input queue for delivery. 1024 */ 1025 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 1026 s = splsoftnet(); 1027 if (mtag != NULL) { 1028 tdbi = (struct tdb_ident *)(mtag + 1); 1029 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 1030 } else { 1031 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1032 IP_FORWARDING, &error); 1033 } 1034 if (sp != NULL) { 1035 /* 1036 * Check security policy against packet attributes. 1037 */ 1038 error = ipsec_in_reject(sp, m); 1039 KEY_FREESP(&sp); 1040 } else { 1041 /* XXX error stat??? */ 1042 error = EINVAL; 1043DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 1044 } 1045 splx(s); 1046 if (error) 1047 goto bad; 1048 } 1049#endif /* FAST_IPSEC */ 1050 1051 /* 1052 * Switch out to protocol's input routine. 1053 */ 1054#if IFA_STATS 1055 if (ia && ip) 1056 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 1057#endif 1058 IP_STATINC(IP_STAT_DELIVERED); 1059 { 1060 int off = hlen, nh = ip->ip_p; 1061 1062 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 1063 return; 1064 } 1065bad: 1066 m_freem(m); 1067 return; 1068 1069badcsum: 1070 IP_STATINC(IP_STAT_BADSUM); 1071 m_freem(m); 1072} 1073 1074/* 1075 * Take incoming datagram fragment and try to 1076 * reassemble it into whole datagram. If a chain for 1077 * reassembly of this datagram already exists, then it 1078 * is given as fp; otherwise have to make a chain. 1079 */ 1080struct mbuf * 1081ip_reass(struct ipqent *ipqe, struct ipq *fp, struct ipqhead *ipqhead) 1082{ 1083 struct mbuf *m = ipqe->ipqe_m; 1084 struct ipqent *nq, *p, *q; 1085 struct ip *ip; 1086 struct mbuf *t; 1087 int hlen = ipqe->ipqe_ip->ip_hl << 2; 1088 int i, next, s; 1089 1090 IPQ_LOCK_CHECK(); 1091 1092 /* 1093 * Presence of header sizes in mbufs 1094 * would confuse code below. 1095 */ 1096 m->m_data += hlen; 1097 m->m_len -= hlen; 1098 1099#ifdef notyet 1100 /* make sure fragment limit is up-to-date */ 1101 CHECK_NMBCLUSTER_PARAMS(); 1102 1103 /* If we have too many fragments, drop the older half. */ 1104 if (ip_nfrags >= ip_maxfrags) 1105 ip_reass_drophalf(void); 1106#endif 1107 1108 /* 1109 * We are about to add a fragment; increment frag count. 1110 */ 1111 ip_nfrags++; 1112 1113 /* 1114 * If first fragment to arrive, create a reassembly queue. 1115 */ 1116 if (fp == 0) { 1117 /* 1118 * Enforce upper bound on number of fragmented packets 1119 * for which we attempt reassembly; 1120 * If maxfrag is 0, never accept fragments. 1121 * If maxfrag is -1, accept all fragments without limitation. 1122 */ 1123 if (ip_maxfragpackets < 0) 1124 ; 1125 else if (ip_nfragpackets >= ip_maxfragpackets) 1126 goto dropfrag; 1127 ip_nfragpackets++; 1128 MALLOC(fp, struct ipq *, sizeof (struct ipq), 1129 M_FTABLE, M_NOWAIT); 1130 if (fp == NULL) 1131 goto dropfrag; 1132 LIST_INSERT_HEAD(ipqhead, fp, ipq_q); 1133 fp->ipq_nfrags = 1; 1134 fp->ipq_ttl = IPFRAGTTL; 1135 fp->ipq_p = ipqe->ipqe_ip->ip_p; 1136 fp->ipq_id = ipqe->ipqe_ip->ip_id; 1137 fp->ipq_tos = ipqe->ipqe_ip->ip_tos; 1138 TAILQ_INIT(&fp->ipq_fragq); 1139 fp->ipq_src = ipqe->ipqe_ip->ip_src; 1140 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 1141 p = NULL; 1142 goto insert; 1143 } else { 1144 fp->ipq_nfrags++; 1145 } 1146 1147 /* 1148 * Find a segment which begins after this one does. 1149 */ 1150 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1151 p = q, q = TAILQ_NEXT(q, ipqe_q)) 1152 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 1153 break; 1154 1155 /* 1156 * If there is a preceding segment, it may provide some of 1157 * our data already. If so, drop the data from the incoming 1158 * segment. If it provides all of our data, drop us. 1159 */ 1160 if (p != NULL) { 1161 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 1162 ntohs(ipqe->ipqe_ip->ip_off); 1163 if (i > 0) { 1164 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 1165 goto dropfrag; 1166 m_adj(ipqe->ipqe_m, i); 1167 ipqe->ipqe_ip->ip_off = 1168 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 1169 ipqe->ipqe_ip->ip_len = 1170 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 1171 } 1172 } 1173 1174 /* 1175 * While we overlap succeeding segments trim them or, 1176 * if they are completely covered, dequeue them. 1177 */ 1178 for (; q != NULL && 1179 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 1180 ntohs(q->ipqe_ip->ip_off); q = nq) { 1181 i = (ntohs(ipqe->ipqe_ip->ip_off) + 1182 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 1183 if (i < ntohs(q->ipqe_ip->ip_len)) { 1184 q->ipqe_ip->ip_len = 1185 htons(ntohs(q->ipqe_ip->ip_len) - i); 1186 q->ipqe_ip->ip_off = 1187 htons(ntohs(q->ipqe_ip->ip_off) + i); 1188 m_adj(q->ipqe_m, i); 1189 break; 1190 } 1191 nq = TAILQ_NEXT(q, ipqe_q); 1192 m_freem(q->ipqe_m); 1193 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1194 s = splvm(); 1195 pool_put(&ipqent_pool, q); 1196 splx(s); 1197 fp->ipq_nfrags--; 1198 ip_nfrags--; 1199 } 1200 1201insert: 1202 /* 1203 * Stick new segment in its place; 1204 * check for complete reassembly. 1205 */ 1206 if (p == NULL) { 1207 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1208 } else { 1209 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1210 } 1211 next = 0; 1212 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1213 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1214 if (ntohs(q->ipqe_ip->ip_off) != next) 1215 return (0); 1216 next += ntohs(q->ipqe_ip->ip_len); 1217 } 1218 if (p->ipqe_mff) 1219 return (0); 1220 1221 /* 1222 * Reassembly is complete. Check for a bogus message size and 1223 * concatenate fragments. 1224 */ 1225 q = TAILQ_FIRST(&fp->ipq_fragq); 1226 ip = q->ipqe_ip; 1227 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1228 IP_STATINC(IP_STAT_TOOLONG); 1229 ip_freef(fp); 1230 return (0); 1231 } 1232 m = q->ipqe_m; 1233 t = m->m_next; 1234 m->m_next = 0; 1235 m_cat(m, t); 1236 nq = TAILQ_NEXT(q, ipqe_q); 1237 s = splvm(); 1238 pool_put(&ipqent_pool, q); 1239 splx(s); 1240 for (q = nq; q != NULL; q = nq) { 1241 t = q->ipqe_m; 1242 nq = TAILQ_NEXT(q, ipqe_q); 1243 s = splvm(); 1244 pool_put(&ipqent_pool, q); 1245 splx(s); 1246 m_cat(m, t); 1247 } 1248 ip_nfrags -= fp->ipq_nfrags; 1249 1250 /* 1251 * Create header for new ip packet by 1252 * modifying header of first packet; 1253 * dequeue and discard fragment reassembly header. 1254 * Make header visible. 1255 */ 1256 ip->ip_len = htons(next); 1257 ip->ip_src = fp->ipq_src; 1258 ip->ip_dst = fp->ipq_dst; 1259 LIST_REMOVE(fp, ipq_q); 1260 FREE(fp, M_FTABLE); 1261 ip_nfragpackets--; 1262 m->m_len += (ip->ip_hl << 2); 1263 m->m_data -= (ip->ip_hl << 2); 1264 /* some debugging cruft by sklower, below, will go away soon */ 1265 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1266 int plen = 0; 1267 for (t = m; t; t = t->m_next) 1268 plen += t->m_len; 1269 m->m_pkthdr.len = plen; 1270 m->m_pkthdr.csum_flags = 0; 1271 } 1272 return (m); 1273 1274dropfrag: 1275 if (fp != 0) 1276 fp->ipq_nfrags--; 1277 ip_nfrags--; 1278 IP_STATINC(IP_STAT_FRAGDROPPED); 1279 m_freem(m); 1280 s = splvm(); 1281 pool_put(&ipqent_pool, ipqe); 1282 splx(s); 1283 return (0); 1284} 1285 1286/* 1287 * Free a fragment reassembly header and all 1288 * associated datagrams. 1289 */ 1290void 1291ip_freef(struct ipq *fp) 1292{ 1293 struct ipqent *q, *p; 1294 u_int nfrags = 0; 1295 int s; 1296 1297 IPQ_LOCK_CHECK(); 1298 1299 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1300 p = TAILQ_NEXT(q, ipqe_q); 1301 m_freem(q->ipqe_m); 1302 nfrags++; 1303 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1304 s = splvm(); 1305 pool_put(&ipqent_pool, q); 1306 splx(s); 1307 } 1308 1309 if (nfrags != fp->ipq_nfrags) 1310 printf("ip_freef: nfrags %d != %d\n", fp->ipq_nfrags, nfrags); 1311 ip_nfrags -= nfrags; 1312 LIST_REMOVE(fp, ipq_q); 1313 FREE(fp, M_FTABLE); 1314 ip_nfragpackets--; 1315} 1316 1317/* 1318 * IP reassembly TTL machinery for multiplicative drop. 1319 */ 1320static u_int fragttl_histo[(IPFRAGTTL+1)]; 1321 1322 1323/* 1324 * Decrement TTL of all reasembly queue entries by `ticks'. 1325 * Count number of distinct fragments (as opposed to partial, fragmented 1326 * datagrams) in the reassembly queue. While we traverse the entire 1327 * reassembly queue, compute and return the median TTL over all fragments. 1328 */ 1329static u_int 1330ip_reass_ttl_decr(u_int ticks) 1331{ 1332 u_int nfrags, median, dropfraction, keepfraction; 1333 struct ipq *fp, *nfp; 1334 int i; 1335 1336 nfrags = 0; 1337 memset(fragttl_histo, 0, sizeof fragttl_histo); 1338 1339 for (i = 0; i < IPREASS_NHASH; i++) { 1340 for (fp = LIST_FIRST(&ipq[i]); fp != NULL; fp = nfp) { 1341 fp->ipq_ttl = ((fp->ipq_ttl <= ticks) ? 1342 0 : fp->ipq_ttl - ticks); 1343 nfp = LIST_NEXT(fp, ipq_q); 1344 if (fp->ipq_ttl == 0) { 1345 IP_STATINC(IP_STAT_FRAGTIMEOUT); 1346 ip_freef(fp); 1347 } else { 1348 nfrags += fp->ipq_nfrags; 1349 fragttl_histo[fp->ipq_ttl] += fp->ipq_nfrags; 1350 } 1351 } 1352 } 1353 1354 KASSERT(ip_nfrags == nfrags); 1355 1356 /* Find median (or other drop fraction) in histogram. */ 1357 dropfraction = (ip_nfrags / 2); 1358 keepfraction = ip_nfrags - dropfraction; 1359 for (i = IPFRAGTTL, median = 0; i >= 0; i--) { 1360 median += fragttl_histo[i]; 1361 if (median >= keepfraction) 1362 break; 1363 } 1364 1365 /* Return TTL of median (or other fraction). */ 1366 return (u_int)i; 1367} 1368 1369void 1370ip_reass_drophalf(void) 1371{ 1372 1373 u_int median_ticks; 1374 /* 1375 * Compute median TTL of all fragments, and count frags 1376 * with that TTL or lower (roughly half of all fragments). 1377 */ 1378 median_ticks = ip_reass_ttl_decr(0); 1379 1380 /* Drop half. */ 1381 median_ticks = ip_reass_ttl_decr(median_ticks); 1382 1383} 1384 1385/* 1386 * IP timer processing; 1387 * if a timer expires on a reassembly 1388 * queue, discard it. 1389 */ 1390void 1391ip_slowtimo(void) 1392{ 1393 static u_int dropscanidx = 0; 1394 u_int i; 1395 u_int median_ttl; 1396 1397 mutex_enter(softnet_lock); 1398 KERNEL_LOCK(1, NULL); 1399 1400 IPQ_LOCK(); 1401 1402 /* Age TTL of all fragments by 1 tick .*/ 1403 median_ttl = ip_reass_ttl_decr(1); 1404 1405 /* make sure fragment limit is up-to-date */ 1406 CHECK_NMBCLUSTER_PARAMS(); 1407 1408 /* If we have too many fragments, drop the older half. */ 1409 if (ip_nfrags > ip_maxfrags) 1410 ip_reass_ttl_decr(median_ttl); 1411 1412 /* 1413 * If we are over the maximum number of fragmented packets 1414 * (due to the limit being lowered), drain off 1415 * enough to get down to the new limit. Start draining 1416 * from the reassembly hashqueue most recently drained. 1417 */ 1418 if (ip_maxfragpackets < 0) 1419 ; 1420 else { 1421 int wrapped = 0; 1422 1423 i = dropscanidx; 1424 while (ip_nfragpackets > ip_maxfragpackets && wrapped == 0) { 1425 while (LIST_FIRST(&ipq[i]) != NULL) 1426 ip_freef(LIST_FIRST(&ipq[i])); 1427 if (++i >= IPREASS_NHASH) { 1428 i = 0; 1429 } 1430 /* 1431 * Dont scan forever even if fragment counters are 1432 * wrong: stop after scanning entire reassembly queue. 1433 */ 1434 if (i == dropscanidx) 1435 wrapped = 1; 1436 } 1437 dropscanidx = i; 1438 } 1439 IPQ_UNLOCK(); 1440 1441 KERNEL_UNLOCK_ONE(NULL); 1442 mutex_exit(softnet_lock); 1443} 1444 1445/* 1446 * Drain off all datagram fragments. 1447 */ 1448void 1449ip_drain(void) 1450{ 1451 1452 mutex_enter(softnet_lock); 1453 KERNEL_LOCK(1, NULL); 1454 1455 /* 1456 * We may be called from a device's interrupt context. If 1457 * the ipq is already busy, just bail out now. 1458 */ 1459 if (ipq_lock_try() != 0) { 1460 /* 1461 * Drop half the total fragments now. If more mbufs are 1462 * needed, we will be called again soon. 1463 */ 1464 ip_reass_drophalf(); 1465 IPQ_UNLOCK(); 1466 } 1467 1468 KERNEL_UNLOCK_ONE(NULL); 1469 mutex_exit(softnet_lock); 1470} 1471 1472/* 1473 * Do option processing on a datagram, 1474 * possibly discarding it if bad options are encountered, 1475 * or forwarding it if source-routed. 1476 * Returns 1 if packet has been forwarded/freed, 1477 * 0 if the packet should be processed further. 1478 */ 1479int 1480ip_dooptions(struct mbuf *m) 1481{ 1482 struct ip *ip = mtod(m, struct ip *); 1483 u_char *cp, *cp0; 1484 struct ip_timestamp *ipt; 1485 struct in_ifaddr *ia; 1486 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1487 struct in_addr dst; 1488 n_time ntime; 1489 1490 dst = ip->ip_dst; 1491 cp = (u_char *)(ip + 1); 1492 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1493 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1494 opt = cp[IPOPT_OPTVAL]; 1495 if (opt == IPOPT_EOL) 1496 break; 1497 if (opt == IPOPT_NOP) 1498 optlen = 1; 1499 else { 1500 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1501 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1502 goto bad; 1503 } 1504 optlen = cp[IPOPT_OLEN]; 1505 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1506 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1507 goto bad; 1508 } 1509 } 1510 switch (opt) { 1511 1512 default: 1513 break; 1514 1515 /* 1516 * Source routing with record. 1517 * Find interface with current destination address. 1518 * If none on this machine then drop if strictly routed, 1519 * or do nothing if loosely routed. 1520 * Record interface address and bring up next address 1521 * component. If strictly routed make sure next 1522 * address is on directly accessible net. 1523 */ 1524 case IPOPT_LSRR: 1525 case IPOPT_SSRR: 1526 if (ip_allowsrcrt == 0) { 1527 type = ICMP_UNREACH; 1528 code = ICMP_UNREACH_NET_PROHIB; 1529 goto bad; 1530 } 1531 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1532 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1533 goto bad; 1534 } 1535 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1536 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1537 goto bad; 1538 } 1539 ipaddr.sin_addr = ip->ip_dst; 1540 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1541 if (ia == 0) { 1542 if (opt == IPOPT_SSRR) { 1543 type = ICMP_UNREACH; 1544 code = ICMP_UNREACH_SRCFAIL; 1545 goto bad; 1546 } 1547 /* 1548 * Loose routing, and not at next destination 1549 * yet; nothing to do except forward. 1550 */ 1551 break; 1552 } 1553 off--; /* 0 origin */ 1554 if ((off + sizeof(struct in_addr)) > optlen) { 1555 /* 1556 * End of source route. Should be for us. 1557 */ 1558 save_rte(cp, ip->ip_src); 1559 break; 1560 } 1561 /* 1562 * locate outgoing interface 1563 */ 1564 bcopy((void *)(cp + off), (void *)&ipaddr.sin_addr, 1565 sizeof(ipaddr.sin_addr)); 1566 if (opt == IPOPT_SSRR) 1567 ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr))); 1568 else 1569 ia = ip_rtaddr(ipaddr.sin_addr); 1570 if (ia == 0) { 1571 type = ICMP_UNREACH; 1572 code = ICMP_UNREACH_SRCFAIL; 1573 goto bad; 1574 } 1575 ip->ip_dst = ipaddr.sin_addr; 1576 bcopy((void *)&ia->ia_addr.sin_addr, 1577 (void *)(cp + off), sizeof(struct in_addr)); 1578 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1579 /* 1580 * Let ip_intr's mcast routing check handle mcast pkts 1581 */ 1582 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1583 break; 1584 1585 case IPOPT_RR: 1586 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1587 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1588 goto bad; 1589 } 1590 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1591 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1592 goto bad; 1593 } 1594 /* 1595 * If no space remains, ignore. 1596 */ 1597 off--; /* 0 origin */ 1598 if ((off + sizeof(struct in_addr)) > optlen) 1599 break; 1600 bcopy((void *)(&ip->ip_dst), (void *)&ipaddr.sin_addr, 1601 sizeof(ipaddr.sin_addr)); 1602 /* 1603 * locate outgoing interface; if we're the destination, 1604 * use the incoming interface (should be same). 1605 */ 1606 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1607 == NULL && 1608 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1609 type = ICMP_UNREACH; 1610 code = ICMP_UNREACH_HOST; 1611 goto bad; 1612 } 1613 bcopy((void *)&ia->ia_addr.sin_addr, 1614 (void *)(cp + off), sizeof(struct in_addr)); 1615 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1616 break; 1617 1618 case IPOPT_TS: 1619 code = cp - (u_char *)ip; 1620 ipt = (struct ip_timestamp *)cp; 1621 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1622 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1623 goto bad; 1624 } 1625 if (ipt->ipt_ptr < 5) { 1626 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1627 goto bad; 1628 } 1629 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1630 if (++ipt->ipt_oflw == 0) { 1631 code = (u_char *)&ipt->ipt_ptr - 1632 (u_char *)ip; 1633 goto bad; 1634 } 1635 break; 1636 } 1637 cp0 = (cp + ipt->ipt_ptr - 1); 1638 switch (ipt->ipt_flg) { 1639 1640 case IPOPT_TS_TSONLY: 1641 break; 1642 1643 case IPOPT_TS_TSANDADDR: 1644 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1645 sizeof(struct in_addr) > ipt->ipt_len) { 1646 code = (u_char *)&ipt->ipt_ptr - 1647 (u_char *)ip; 1648 goto bad; 1649 } 1650 ipaddr.sin_addr = dst; 1651 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1652 m->m_pkthdr.rcvif)); 1653 if (ia == 0) 1654 continue; 1655 bcopy(&ia->ia_addr.sin_addr, 1656 cp0, sizeof(struct in_addr)); 1657 ipt->ipt_ptr += sizeof(struct in_addr); 1658 break; 1659 1660 case IPOPT_TS_PRESPEC: 1661 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1662 sizeof(struct in_addr) > ipt->ipt_len) { 1663 code = (u_char *)&ipt->ipt_ptr - 1664 (u_char *)ip; 1665 goto bad; 1666 } 1667 bcopy(cp0, &ipaddr.sin_addr, 1668 sizeof(struct in_addr)); 1669 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1670 == NULL) 1671 continue; 1672 ipt->ipt_ptr += sizeof(struct in_addr); 1673 break; 1674 1675 default: 1676 /* XXX can't take &ipt->ipt_flg */ 1677 code = (u_char *)&ipt->ipt_ptr - 1678 (u_char *)ip + 1; 1679 goto bad; 1680 } 1681 ntime = iptime(); 1682 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1683 memmove((char *)cp + ipt->ipt_ptr - 1, cp0, 1684 sizeof(n_time)); 1685 ipt->ipt_ptr += sizeof(n_time); 1686 } 1687 } 1688 if (forward) { 1689 if (ip_forwsrcrt == 0) { 1690 type = ICMP_UNREACH; 1691 code = ICMP_UNREACH_SRCFAIL; 1692 goto bad; 1693 } 1694 ip_forward(m, 1); 1695 return (1); 1696 } 1697 return (0); 1698bad: 1699 icmp_error(m, type, code, 0, 0); 1700 IP_STATINC(IP_STAT_BADOPTIONS); 1701 return (1); 1702} 1703 1704/* 1705 * Given address of next destination (final or next hop), 1706 * return internet address info of interface to be used to get there. 1707 */ 1708struct in_ifaddr * 1709ip_rtaddr(struct in_addr dst) 1710{ 1711 struct rtentry *rt; 1712 union { 1713 struct sockaddr dst; 1714 struct sockaddr_in dst4; 1715 } u; 1716 1717 sockaddr_in_init(&u.dst4, &dst, 0); 1718 1719 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) 1720 return NULL; 1721 1722 return ifatoia(rt->rt_ifa); 1723} 1724 1725/* 1726 * Save incoming source route for use in replies, 1727 * to be picked up later by ip_srcroute if the receiver is interested. 1728 */ 1729void 1730save_rte(u_char *option, struct in_addr dst) 1731{ 1732 unsigned olen; 1733 1734 olen = option[IPOPT_OLEN]; 1735#ifdef DIAGNOSTIC 1736 if (ipprintfs) 1737 printf("save_rte: olen %d\n", olen); 1738#endif /* 0 */ 1739 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1740 return; 1741 bcopy((void *)option, (void *)ip_srcrt.srcopt, olen); 1742 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1743 ip_srcrt.dst = dst; 1744} 1745 1746/* 1747 * Retrieve incoming source route for use in replies, 1748 * in the same form used by setsockopt. 1749 * The first hop is placed before the options, will be removed later. 1750 */ 1751struct mbuf * 1752ip_srcroute(void) 1753{ 1754 struct in_addr *p, *q; 1755 struct mbuf *m; 1756 1757 if (ip_nhops == 0) 1758 return NULL; 1759 m = m_get(M_DONTWAIT, MT_SOOPTS); 1760 if (m == 0) 1761 return NULL; 1762 1763 MCLAIM(m, &inetdomain.dom_mowner); 1764#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1765 1766 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1767 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1768 OPTSIZ; 1769#ifdef DIAGNOSTIC 1770 if (ipprintfs) 1771 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1772#endif 1773 1774 /* 1775 * First save first hop for return route 1776 */ 1777 p = &ip_srcrt.route[ip_nhops - 1]; 1778 *(mtod(m, struct in_addr *)) = *p--; 1779#ifdef DIAGNOSTIC 1780 if (ipprintfs) 1781 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1782#endif 1783 1784 /* 1785 * Copy option fields and padding (nop) to mbuf. 1786 */ 1787 ip_srcrt.nop = IPOPT_NOP; 1788 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1789 memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop, 1790 OPTSIZ); 1791 q = (struct in_addr *)(mtod(m, char *) + 1792 sizeof(struct in_addr) + OPTSIZ); 1793#undef OPTSIZ 1794 /* 1795 * Record return path as an IP source route, 1796 * reversing the path (pointers are now aligned). 1797 */ 1798 while (p >= ip_srcrt.route) { 1799#ifdef DIAGNOSTIC 1800 if (ipprintfs) 1801 printf(" %x", ntohl(q->s_addr)); 1802#endif 1803 *q++ = *p--; 1804 } 1805 /* 1806 * Last hop goes to final destination. 1807 */ 1808 *q = ip_srcrt.dst; 1809#ifdef DIAGNOSTIC 1810 if (ipprintfs) 1811 printf(" %x\n", ntohl(q->s_addr)); 1812#endif 1813 return (m); 1814} 1815 1816const int inetctlerrmap[PRC_NCMDS] = { 1817 [PRC_MSGSIZE] = EMSGSIZE, 1818 [PRC_HOSTDEAD] = EHOSTDOWN, 1819 [PRC_HOSTUNREACH] = EHOSTUNREACH, 1820 [PRC_UNREACH_NET] = EHOSTUNREACH, 1821 [PRC_UNREACH_HOST] = EHOSTUNREACH, 1822 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED, 1823 [PRC_UNREACH_PORT] = ECONNREFUSED, 1824 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH, 1825 [PRC_PARAMPROB] = ENOPROTOOPT, 1826}; 1827 1828/* 1829 * Forward a packet. If some error occurs return the sender 1830 * an icmp packet. Note we can't always generate a meaningful 1831 * icmp message because icmp doesn't have a large enough repertoire 1832 * of codes and types. 1833 * 1834 * If not forwarding, just drop the packet. This could be confusing 1835 * if ipforwarding was zero but some routing protocol was advancing 1836 * us as a gateway to somewhere. However, we must let the routing 1837 * protocol deal with that. 1838 * 1839 * The srcrt parameter indicates whether the packet is being forwarded 1840 * via a source route. 1841 */ 1842void 1843ip_forward(struct mbuf *m, int srcrt) 1844{ 1845 struct ip *ip = mtod(m, struct ip *); 1846 struct rtentry *rt; 1847 int error, type = 0, code = 0, destmtu = 0; 1848 struct mbuf *mcopy; 1849 n_long dest; 1850 union { 1851 struct sockaddr dst; 1852 struct sockaddr_in dst4; 1853 } u; 1854 1855 /* 1856 * We are now in the output path. 1857 */ 1858 MCLAIM(m, &ip_tx_mowner); 1859 1860 /* 1861 * Clear any in-bound checksum flags for this packet. 1862 */ 1863 m->m_pkthdr.csum_flags = 0; 1864 1865 dest = 0; 1866#ifdef DIAGNOSTIC 1867 if (ipprintfs) { 1868 printf("forward: src %s ", inet_ntoa(ip->ip_src)); 1869 printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl); 1870 } 1871#endif 1872 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1873 IP_STATINC(IP_STAT_CANTFORWARD); 1874 m_freem(m); 1875 return; 1876 } 1877 if (ip->ip_ttl <= IPTTLDEC) { 1878 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1879 return; 1880 } 1881 1882 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0); 1883 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) { 1884 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0); 1885 return; 1886 } 1887 1888 /* 1889 * Save at most 68 bytes of the packet in case 1890 * we need to generate an ICMP message to the src. 1891 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1892 */ 1893 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1894 if (mcopy) 1895 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1896 1897 ip->ip_ttl -= IPTTLDEC; 1898 1899 /* 1900 * If forwarding packet using same interface that it came in on, 1901 * perhaps should send a redirect to sender to shortcut a hop. 1902 * Only send redirect if source is sending directly to us, 1903 * and if packet was not source routed (or has any options). 1904 * Also, don't send redirect if forwarding using a default route 1905 * or a route modified by a redirect. 1906 */ 1907 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1908 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1909 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) && 1910 ipsendredirects && !srcrt) { 1911 if (rt->rt_ifa && 1912 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1913 ifatoia(rt->rt_ifa)->ia_subnet) { 1914 if (rt->rt_flags & RTF_GATEWAY) 1915 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1916 else 1917 dest = ip->ip_dst.s_addr; 1918 /* 1919 * Router requirements says to only send host 1920 * redirects. 1921 */ 1922 type = ICMP_REDIRECT; 1923 code = ICMP_REDIRECT_HOST; 1924#ifdef DIAGNOSTIC 1925 if (ipprintfs) 1926 printf("redirect (%d) to %x\n", code, 1927 (u_int32_t)dest); 1928#endif 1929 } 1930 } 1931 1932 error = ip_output(m, NULL, &ipforward_rt, 1933 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1934 (struct ip_moptions *)NULL, (struct socket *)NULL); 1935 1936 if (error) 1937 IP_STATINC(IP_STAT_CANTFORWARD); 1938 else { 1939 uint64_t *ips = IP_STAT_GETREF(); 1940 ips[IP_STAT_FORWARD]++; 1941 if (type) { 1942 ips[IP_STAT_REDIRECTSENT]++; 1943 IP_STAT_PUTREF(); 1944 } else { 1945 IP_STAT_PUTREF(); 1946 if (mcopy) { 1947#ifdef GATEWAY 1948 if (mcopy->m_flags & M_CANFASTFWD) 1949 ipflow_create(&ipforward_rt, mcopy); 1950#endif 1951 m_freem(mcopy); 1952 } 1953 return; 1954 } 1955 } 1956 if (mcopy == NULL) 1957 return; 1958 1959 switch (error) { 1960 1961 case 0: /* forwarded, but need redirect */ 1962 /* type, code set above */ 1963 break; 1964 1965 case ENETUNREACH: /* shouldn't happen, checked above */ 1966 case EHOSTUNREACH: 1967 case ENETDOWN: 1968 case EHOSTDOWN: 1969 default: 1970 type = ICMP_UNREACH; 1971 code = ICMP_UNREACH_HOST; 1972 break; 1973 1974 case EMSGSIZE: 1975 type = ICMP_UNREACH; 1976 code = ICMP_UNREACH_NEEDFRAG; 1977 1978 if ((rt = rtcache_validate(&ipforward_rt)) != NULL) { 1979 1980#if defined(IPSEC) || defined(FAST_IPSEC) 1981 /* 1982 * If the packet is routed over IPsec tunnel, tell the 1983 * originator the tunnel MTU. 1984 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1985 * XXX quickhack!!! 1986 */ 1987 1988 struct secpolicy *sp; 1989 int ipsecerror; 1990 size_t ipsechdr; 1991 struct route *ro; 1992 1993 sp = ipsec4_getpolicybyaddr(mcopy, 1994 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1995 &ipsecerror); 1996#endif 1997 1998 destmtu = rt->rt_ifp->if_mtu; 1999#if defined(IPSEC) || defined(FAST_IPSEC) 2000 if (sp != NULL) { 2001 /* count IPsec header size */ 2002 ipsechdr = ipsec4_hdrsiz(mcopy, 2003 IPSEC_DIR_OUTBOUND, NULL); 2004 2005 /* 2006 * find the correct route for outer IPv4 2007 * header, compute tunnel MTU. 2008 */ 2009 2010 if (sp->req != NULL 2011 && sp->req->sav != NULL 2012 && sp->req->sav->sah != NULL) { 2013 ro = &sp->req->sav->sah->sa_route; 2014 if (rt && rt->rt_ifp) { 2015 destmtu = 2016 rt->rt_rmx.rmx_mtu ? 2017 rt->rt_rmx.rmx_mtu : 2018 rt->rt_ifp->if_mtu; 2019 destmtu -= ipsechdr; 2020 } 2021 } 2022 2023#ifdef IPSEC 2024 key_freesp(sp); 2025#else 2026 KEY_FREESP(&sp); 2027#endif 2028 } 2029#endif /*defined(IPSEC) || defined(FAST_IPSEC)*/ 2030 } 2031 IP_STATINC(IP_STAT_CANTFRAG); 2032 break; 2033 2034 case ENOBUFS: 2035#if 1 2036 /* 2037 * a router should not generate ICMP_SOURCEQUENCH as 2038 * required in RFC1812 Requirements for IP Version 4 Routers. 2039 * source quench could be a big problem under DoS attacks, 2040 * or if the underlying interface is rate-limited. 2041 */ 2042 if (mcopy) 2043 m_freem(mcopy); 2044 return; 2045#else 2046 type = ICMP_SOURCEQUENCH; 2047 code = 0; 2048 break; 2049#endif 2050 } 2051 icmp_error(mcopy, type, code, dest, destmtu); 2052} 2053 2054void 2055ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 2056 struct mbuf *m) 2057{ 2058 2059 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 2060 struct timeval tv; 2061 2062 microtime(&tv); 2063 *mp = sbcreatecontrol((void *) &tv, sizeof(tv), 2064 SCM_TIMESTAMP, SOL_SOCKET); 2065 if (*mp) 2066 mp = &(*mp)->m_next; 2067 } 2068 if (inp->inp_flags & INP_RECVDSTADDR) { 2069 *mp = sbcreatecontrol((void *) &ip->ip_dst, 2070 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 2071 if (*mp) 2072 mp = &(*mp)->m_next; 2073 } 2074#ifdef notyet 2075 /* 2076 * XXX 2077 * Moving these out of udp_input() made them even more broken 2078 * than they already were. 2079 * - fenner@parc.xerox.com 2080 */ 2081 /* options were tossed already */ 2082 if (inp->inp_flags & INP_RECVOPTS) { 2083 *mp = sbcreatecontrol((void *) opts_deleted_above, 2084 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 2085 if (*mp) 2086 mp = &(*mp)->m_next; 2087 } 2088 /* ip_srcroute doesn't do what we want here, need to fix */ 2089 if (inp->inp_flags & INP_RECVRETOPTS) { 2090 *mp = sbcreatecontrol((void *) ip_srcroute(), 2091 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 2092 if (*mp) 2093 mp = &(*mp)->m_next; 2094 } 2095#endif 2096 if (inp->inp_flags & INP_RECVIF) { 2097 struct sockaddr_dl sdl; 2098 2099 sockaddr_dl_init(&sdl, sizeof(sdl), 2100 (m->m_pkthdr.rcvif != NULL) 2101 ? m->m_pkthdr.rcvif->if_index 2102 : 0, 2103 0, NULL, 0, NULL, 0); 2104 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP); 2105 if (*mp) 2106 mp = &(*mp)->m_next; 2107 } 2108} 2109 2110/* 2111 * sysctl helper routine for net.inet.ip.forwsrcrt. 2112 */ 2113static int 2114sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS) 2115{ 2116 int error, tmp; 2117 struct sysctlnode node; 2118 2119 node = *rnode; 2120 tmp = ip_forwsrcrt; 2121 node.sysctl_data = &tmp; 2122 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2123 if (error || newp == NULL) 2124 return (error); 2125 2126 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT, 2127 0, NULL, NULL, NULL)) 2128 return (EPERM); 2129 2130 ip_forwsrcrt = tmp; 2131 2132 return (0); 2133} 2134 2135/* 2136 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the 2137 * range of the new value and tweaks timers if it changes. 2138 */ 2139static int 2140sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS) 2141{ 2142 int error, tmp; 2143 struct sysctlnode node; 2144 2145 node = *rnode; 2146 tmp = ip_mtudisc_timeout; 2147 node.sysctl_data = &tmp; 2148 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2149 if (error || newp == NULL) 2150 return (error); 2151 if (tmp < 0) 2152 return (EINVAL); 2153 2154 ip_mtudisc_timeout = tmp; 2155 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 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 s; 2168 2169 s = sysctl_lookup(SYSCTLFN_CALL(rnode)); 2170 if (s || newp == NULL) 2171 return (s); 2172 2173 s = splsoftnet(); 2174 ipflow_prune(); 2175 splx(s); 2176 2177 return (0); 2178} 2179 2180static int 2181sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS) 2182{ 2183 int error, tmp; 2184 struct sysctlnode node; 2185 2186 node = *rnode; 2187 tmp = ip_hashsize; 2188 node.sysctl_data = &tmp; 2189 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2190 if (error || newp == NULL) 2191 return (error); 2192 2193 if ((tmp & (tmp - 1)) == 0 && tmp != 0) { 2194 /* 2195 * Can only fail due to malloc() 2196 */ 2197 if (ipflow_invalidate_all(tmp)) 2198 return ENOMEM; 2199 } else { 2200 /* 2201 * EINVAL if not a power of 2 2202 */ 2203 return EINVAL; 2204 } 2205 2206 return (0); 2207} 2208#endif /* GATEWAY */ 2209 2210static int 2211sysctl_net_inet_ip_stats(SYSCTLFN_ARGS) 2212{ 2213 netstat_sysctl_context ctx; 2214 uint64_t ips[IP_NSTATS]; 2215 2216 ctx.ctx_stat = ipstat_percpu; 2217 ctx.ctx_counters = ips; 2218 ctx.ctx_ncounters = IP_NSTATS; 2219 return (NETSTAT_SYSCTL(&ctx)); 2220} 2221 2222SYSCTL_SETUP(sysctl_net_inet_ip_setup, "sysctl net.inet.ip subtree setup") 2223{ 2224 extern int subnetsarelocal, hostzeroisbroadcast; 2225 2226 sysctl_createv(clog, 0, NULL, NULL, 2227 CTLFLAG_PERMANENT, 2228 CTLTYPE_NODE, "net", NULL, 2229 NULL, 0, NULL, 0, 2230 CTL_NET, CTL_EOL); 2231 sysctl_createv(clog, 0, NULL, NULL, 2232 CTLFLAG_PERMANENT, 2233 CTLTYPE_NODE, "inet", 2234 SYSCTL_DESCR("PF_INET related settings"), 2235 NULL, 0, NULL, 0, 2236 CTL_NET, PF_INET, CTL_EOL); 2237 sysctl_createv(clog, 0, NULL, NULL, 2238 CTLFLAG_PERMANENT, 2239 CTLTYPE_NODE, "ip", 2240 SYSCTL_DESCR("IPv4 related settings"), 2241 NULL, 0, NULL, 0, 2242 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL); 2243 2244 sysctl_createv(clog, 0, NULL, NULL, 2245 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2246 CTLTYPE_INT, "forwarding", 2247 SYSCTL_DESCR("Enable forwarding of INET datagrams"), 2248 NULL, 0, &ipforwarding, 0, 2249 CTL_NET, PF_INET, IPPROTO_IP, 2250 IPCTL_FORWARDING, CTL_EOL); 2251 sysctl_createv(clog, 0, NULL, NULL, 2252 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2253 CTLTYPE_INT, "redirect", 2254 SYSCTL_DESCR("Enable sending of ICMP redirect messages"), 2255 NULL, 0, &ipsendredirects, 0, 2256 CTL_NET, PF_INET, IPPROTO_IP, 2257 IPCTL_SENDREDIRECTS, CTL_EOL); 2258 sysctl_createv(clog, 0, NULL, NULL, 2259 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2260 CTLTYPE_INT, "ttl", 2261 SYSCTL_DESCR("Default TTL for an INET datagram"), 2262 NULL, 0, &ip_defttl, 0, 2263 CTL_NET, PF_INET, IPPROTO_IP, 2264 IPCTL_DEFTTL, CTL_EOL); 2265#ifdef IPCTL_DEFMTU 2266 sysctl_createv(clog, 0, NULL, NULL, 2267 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */, 2268 CTLTYPE_INT, "mtu", 2269 SYSCTL_DESCR("Default MTA for an INET route"), 2270 NULL, 0, &ip_mtu, 0, 2271 CTL_NET, PF_INET, IPPROTO_IP, 2272 IPCTL_DEFMTU, CTL_EOL); 2273#endif /* IPCTL_DEFMTU */ 2274 sysctl_createv(clog, 0, NULL, NULL, 2275 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2276 CTLTYPE_INT, "forwsrcrt", 2277 SYSCTL_DESCR("Enable forwarding of source-routed " 2278 "datagrams"), 2279 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0, 2280 CTL_NET, PF_INET, IPPROTO_IP, 2281 IPCTL_FORWSRCRT, CTL_EOL); 2282 sysctl_createv(clog, 0, NULL, NULL, 2283 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2284 CTLTYPE_INT, "directed-broadcast", 2285 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"), 2286 NULL, 0, &ip_directedbcast, 0, 2287 CTL_NET, PF_INET, IPPROTO_IP, 2288 IPCTL_DIRECTEDBCAST, CTL_EOL); 2289 sysctl_createv(clog, 0, NULL, NULL, 2290 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2291 CTLTYPE_INT, "allowsrcrt", 2292 SYSCTL_DESCR("Accept source-routed datagrams"), 2293 NULL, 0, &ip_allowsrcrt, 0, 2294 CTL_NET, PF_INET, IPPROTO_IP, 2295 IPCTL_ALLOWSRCRT, CTL_EOL); 2296 sysctl_createv(clog, 0, NULL, NULL, 2297 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2298 CTLTYPE_INT, "subnetsarelocal", 2299 SYSCTL_DESCR("Whether logical subnets are considered " 2300 "local"), 2301 NULL, 0, &subnetsarelocal, 0, 2302 CTL_NET, PF_INET, IPPROTO_IP, 2303 IPCTL_SUBNETSARELOCAL, CTL_EOL); 2304 sysctl_createv(clog, 0, NULL, NULL, 2305 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2306 CTLTYPE_INT, "mtudisc", 2307 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"), 2308 NULL, 0, &ip_mtudisc, 0, 2309 CTL_NET, PF_INET, IPPROTO_IP, 2310 IPCTL_MTUDISC, CTL_EOL); 2311 sysctl_createv(clog, 0, NULL, NULL, 2312 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2313 CTLTYPE_INT, "anonportmin", 2314 SYSCTL_DESCR("Lowest ephemeral port number to assign"), 2315 sysctl_net_inet_ip_ports, 0, &anonportmin, 0, 2316 CTL_NET, PF_INET, IPPROTO_IP, 2317 IPCTL_ANONPORTMIN, CTL_EOL); 2318 sysctl_createv(clog, 0, NULL, NULL, 2319 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2320 CTLTYPE_INT, "anonportmax", 2321 SYSCTL_DESCR("Highest ephemeral port number to assign"), 2322 sysctl_net_inet_ip_ports, 0, &anonportmax, 0, 2323 CTL_NET, PF_INET, IPPROTO_IP, 2324 IPCTL_ANONPORTMAX, CTL_EOL); 2325 sysctl_createv(clog, 0, NULL, NULL, 2326 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2327 CTLTYPE_INT, "mtudisctimeout", 2328 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"), 2329 sysctl_net_inet_ip_pmtudto, 0, &ip_mtudisc_timeout, 0, 2330 CTL_NET, PF_INET, IPPROTO_IP, 2331 IPCTL_MTUDISCTIMEOUT, CTL_EOL); 2332#ifdef GATEWAY 2333 sysctl_createv(clog, 0, NULL, NULL, 2334 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2335 CTLTYPE_INT, "maxflows", 2336 SYSCTL_DESCR("Number of flows for fast forwarding"), 2337 sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0, 2338 CTL_NET, PF_INET, IPPROTO_IP, 2339 IPCTL_MAXFLOWS, CTL_EOL); 2340 sysctl_createv(clog, 0, NULL, NULL, 2341 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2342 CTLTYPE_INT, "hashsize", 2343 SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"), 2344 sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0, 2345 CTL_NET, PF_INET, IPPROTO_IP, 2346 CTL_CREATE, CTL_EOL); 2347#endif /* GATEWAY */ 2348 sysctl_createv(clog, 0, NULL, NULL, 2349 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2350 CTLTYPE_INT, "hostzerobroadcast", 2351 SYSCTL_DESCR("All zeroes address is broadcast address"), 2352 NULL, 0, &hostzeroisbroadcast, 0, 2353 CTL_NET, PF_INET, IPPROTO_IP, 2354 IPCTL_HOSTZEROBROADCAST, CTL_EOL); 2355#if NGIF > 0 2356 sysctl_createv(clog, 0, NULL, NULL, 2357 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2358 CTLTYPE_INT, "gifttl", 2359 SYSCTL_DESCR("Default TTL for a gif tunnel datagram"), 2360 NULL, 0, &ip_gif_ttl, 0, 2361 CTL_NET, PF_INET, IPPROTO_IP, 2362 IPCTL_GIF_TTL, CTL_EOL); 2363#endif /* NGIF */ 2364#ifndef IPNOPRIVPORTS 2365 sysctl_createv(clog, 0, NULL, NULL, 2366 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2367 CTLTYPE_INT, "lowportmin", 2368 SYSCTL_DESCR("Lowest privileged ephemeral port number " 2369 "to assign"), 2370 sysctl_net_inet_ip_ports, 0, &lowportmin, 0, 2371 CTL_NET, PF_INET, IPPROTO_IP, 2372 IPCTL_LOWPORTMIN, CTL_EOL); 2373 sysctl_createv(clog, 0, NULL, NULL, 2374 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2375 CTLTYPE_INT, "lowportmax", 2376 SYSCTL_DESCR("Highest privileged ephemeral port number " 2377 "to assign"), 2378 sysctl_net_inet_ip_ports, 0, &lowportmax, 0, 2379 CTL_NET, PF_INET, IPPROTO_IP, 2380 IPCTL_LOWPORTMAX, CTL_EOL); 2381#endif /* IPNOPRIVPORTS */ 2382 sysctl_createv(clog, 0, NULL, NULL, 2383 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2384 CTLTYPE_INT, "maxfragpackets", 2385 SYSCTL_DESCR("Maximum number of fragments to retain for " 2386 "possible reassembly"), 2387 NULL, 0, &ip_maxfragpackets, 0, 2388 CTL_NET, PF_INET, IPPROTO_IP, 2389 IPCTL_MAXFRAGPACKETS, CTL_EOL); 2390#if NGRE > 0 2391 sysctl_createv(clog, 0, NULL, NULL, 2392 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2393 CTLTYPE_INT, "grettl", 2394 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"), 2395 NULL, 0, &ip_gre_ttl, 0, 2396 CTL_NET, PF_INET, IPPROTO_IP, 2397 IPCTL_GRE_TTL, CTL_EOL); 2398#endif /* NGRE */ 2399 sysctl_createv(clog, 0, NULL, NULL, 2400 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2401 CTLTYPE_INT, "checkinterface", 2402 SYSCTL_DESCR("Enable receive side of Strong ES model " 2403 "from RFC1122"), 2404 NULL, 0, &ip_checkinterface, 0, 2405 CTL_NET, PF_INET, IPPROTO_IP, 2406 IPCTL_CHECKINTERFACE, CTL_EOL); 2407 sysctl_createv(clog, 0, NULL, NULL, 2408 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2409 CTLTYPE_INT, "random_id", 2410 SYSCTL_DESCR("Assign random ip_id values"), 2411 NULL, 0, &ip_do_randomid, 0, 2412 CTL_NET, PF_INET, IPPROTO_IP, 2413 IPCTL_RANDOMID, CTL_EOL); 2414 sysctl_createv(clog, 0, NULL, NULL, 2415 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2416 CTLTYPE_INT, "do_loopback_cksum", 2417 SYSCTL_DESCR("Perform IP checksum on loopback"), 2418 NULL, 0, &ip_do_loopback_cksum, 0, 2419 CTL_NET, PF_INET, IPPROTO_IP, 2420 IPCTL_LOOPBACKCKSUM, CTL_EOL); 2421 sysctl_createv(clog, 0, NULL, NULL, 2422 CTLFLAG_PERMANENT, 2423 CTLTYPE_STRUCT, "stats", 2424 SYSCTL_DESCR("IP statistics"), 2425 sysctl_net_inet_ip_stats, 0, NULL, 0, 2426 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS, 2427 CTL_EOL); 2428} 2429 2430void 2431ip_statinc(u_int stat) 2432{ 2433 2434 KASSERT(stat < IP_NSTATS); 2435 IP_STATINC(stat); 2436} 2437