1 /* $NetBSD: ip_input.c,v 1.277 2008/12/17 20:51:37 cegger Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 50 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 51 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 52 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 53 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 54 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 55 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 56 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 57 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 58 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 59 * POSSIBILITY OF SUCH DAMAGE. 60 */ 61 62 /* 63 * Copyright (c) 1982, 1986, 1988, 1993 64 * The Regents of the University of California. All rights reserved. 65 * 66 * Redistribution and use in source and binary forms, with or without 67 * modification, are permitted provided that the following conditions 68 * are met: 69 * 1. Redistributions of source code must retain the above copyright 70 * notice, this list of conditions and the following disclaimer. 71 * 2. Redistributions in binary form must reproduce the above copyright 72 * notice, this list of conditions and the following disclaimer in the 73 * documentation and/or other materials provided with the distribution. 74 * 3. Neither the name of the University nor the names of its contributors 75 * may be used to endorse or promote products derived from this software 76 * without specific prior written permission. 77 * 78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 81 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 88 * SUCH DAMAGE. 89 * 90 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 91 */ 92 93 #include <sys/cdefs.h> 94 __KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.277 2008/12/17 20:51:37 cegger Exp $"); 95 96 #include "opt_inet.h" 97 #include "opt_gateway.h" 98 #include "opt_pfil_hooks.h" 99 #include "opt_ipsec.h" 100 #include "opt_mrouting.h" 101 #include "opt_mbuftrace.h" 102 #include "opt_inet_csum.h" 103 104 #include <sys/param.h> 105 #include <sys/systm.h> 106 #include <sys/malloc.h> 107 #include <sys/mbuf.h> 108 #include <sys/domain.h> 109 #include <sys/protosw.h> 110 #include <sys/socket.h> 111 #include <sys/socketvar.h> 112 #include <sys/errno.h> 113 #include <sys/time.h> 114 #include <sys/kernel.h> 115 #include <sys/pool.h> 116 #include <sys/sysctl.h> 117 #include <sys/kauth.h> 118 119 #include <net/if.h> 120 #include <net/if_dl.h> 121 #include <net/route.h> 122 #include <net/pfil.h> 123 124 #include <netinet/in.h> 125 #include <netinet/in_systm.h> 126 #include <netinet/ip.h> 127 #include <netinet/in_pcb.h> 128 #include <netinet/in_proto.h> 129 #include <netinet/in_var.h> 130 #include <netinet/ip_var.h> 131 #include <netinet/ip_private.h> 132 #include <netinet/ip_icmp.h> 133 /* just for gif_ttl */ 134 #include <netinet/in_gif.h> 135 #include "gif.h" 136 #include <net/if_gre.h> 137 #include "gre.h" 138 139 #ifdef MROUTING 140 #include <netinet/ip_mroute.h> 141 #endif 142 143 #ifdef IPSEC 144 #include <netinet6/ipsec.h> 145 #include <netinet6/ipsec_private.h> 146 #include <netkey/key.h> 147 #endif 148 #ifdef FAST_IPSEC 149 #include <netipsec/ipsec.h> 150 #include <netipsec/key.h> 151 #endif /* FAST_IPSEC*/ 152 153 #ifndef IPFORWARDING 154 #ifdef GATEWAY 155 #define IPFORWARDING 1 /* forward IP packets not for us */ 156 #else /* GATEWAY */ 157 #define IPFORWARDING 0 /* don't forward IP packets not for us */ 158 #endif /* GATEWAY */ 159 #endif /* IPFORWARDING */ 160 #ifndef IPSENDREDIRECTS 161 #define IPSENDREDIRECTS 1 162 #endif 163 #ifndef IPFORWSRCRT 164 #define IPFORWSRCRT 1 /* forward source-routed packets */ 165 #endif 166 #ifndef IPALLOWSRCRT 167 #define IPALLOWSRCRT 1 /* allow source-routed packets */ 168 #endif 169 #ifndef IPMTUDISC 170 #define IPMTUDISC 1 171 #endif 172 #ifndef IPMTUDISCTIMEOUT 173 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 174 #endif 175 176 /* 177 * Note: DIRECTED_BROADCAST is handled this way so that previous 178 * configuration using this option will Just Work. 179 */ 180 #ifndef IPDIRECTEDBCAST 181 #ifdef DIRECTED_BROADCAST 182 #define IPDIRECTEDBCAST 1 183 #else 184 #define IPDIRECTEDBCAST 0 185 #endif /* DIRECTED_BROADCAST */ 186 #endif /* IPDIRECTEDBCAST */ 187 int ipforwarding = IPFORWARDING; 188 int ipsendredirects = IPSENDREDIRECTS; 189 int ip_defttl = IPDEFTTL; 190 int ip_forwsrcrt = IPFORWSRCRT; 191 int ip_directedbcast = IPDIRECTEDBCAST; 192 int ip_allowsrcrt = IPALLOWSRCRT; 193 int ip_mtudisc = IPMTUDISC; 194 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 195 #ifdef DIAGNOSTIC 196 int ipprintfs = 0; 197 #endif 198 199 int ip_do_randomid = 0; 200 201 /* 202 * XXX - Setting ip_checkinterface mostly implements the receive side of 203 * the Strong ES model described in RFC 1122, but since the routing table 204 * and transmit implementation do not implement the Strong ES model, 205 * setting this to 1 results in an odd hybrid. 206 * 207 * XXX - ip_checkinterface currently must be disabled if you use ipnat 208 * to translate the destination address to another local interface. 209 * 210 * XXX - ip_checkinterface must be disabled if you add IP aliases 211 * to the loopback interface instead of the interface where the 212 * packets for those addresses are received. 213 */ 214 int ip_checkinterface = 0; 215 216 217 struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 218 219 int ipqmaxlen = IFQ_MAXLEN; 220 u_long in_ifaddrhash; /* size of hash table - 1 */ 221 int in_ifaddrentries; /* total number of addrs */ 222 struct in_ifaddrhead in_ifaddrhead; 223 struct in_ifaddrhashhead *in_ifaddrhashtbl; 224 u_long in_multihash; /* size of hash table - 1 */ 225 int in_multientries; /* total number of addrs */ 226 struct in_multihashhead *in_multihashtbl; 227 struct ifqueue ipintrq; 228 uint16_t ip_id; 229 230 percpu_t *ipstat_percpu; 231 232 #ifdef PFIL_HOOKS 233 struct pfil_head inet_pfil_hook; 234 #endif 235 236 /* 237 * Cached copy of nmbclusters. If nbclusters is different, 238 * recalculate IP parameters derived from nmbclusters. 239 */ 240 static int ip_nmbclusters; /* copy of nmbclusters */ 241 static void ip_nmbclusters_changed(void); /* recalc limits */ 242 243 #define CHECK_NMBCLUSTER_PARAMS() \ 244 do { \ 245 if (__predict_false(ip_nmbclusters != nmbclusters)) \ 246 ip_nmbclusters_changed(); \ 247 } while (/*CONSTCOND*/0) 248 249 /* IP datagram reassembly queues (hashed) */ 250 #define IPREASS_NHASH_LOG2 6 251 #define IPREASS_NHASH (1 << IPREASS_NHASH_LOG2) 252 #define IPREASS_HMASK (IPREASS_NHASH - 1) 253 #define IPREASS_HASH(x,y) \ 254 (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK) 255 struct ipqhead ipq[IPREASS_NHASH]; 256 int ipq_locked; 257 static int ip_nfragpackets; /* packets in reass queue */ 258 static int ip_nfrags; /* total fragments in reass queues */ 259 260 int ip_maxfragpackets = 200; /* limit on packets. XXX sysctl */ 261 int ip_maxfrags; /* limit on fragments. XXX sysctl */ 262 263 264 /* 265 * Additive-Increase/Multiplicative-Decrease (AIMD) strategy for 266 * IP reassembly queue buffer managment. 267 * 268 * We keep a count of total IP fragments (NB: not fragmented packets!) 269 * awaiting reassembly (ip_nfrags) and a limit (ip_maxfrags) on fragments. 270 * If ip_nfrags exceeds ip_maxfrags the limit, we drop half the 271 * total fragments in reassembly queues.This AIMD policy avoids 272 * repeatedly deleting single packets under heavy fragmentation load 273 * (e.g., from lossy NFS peers). 274 */ 275 static u_int ip_reass_ttl_decr(u_int ticks); 276 static void ip_reass_drophalf(void); 277 278 279 static inline int ipq_lock_try(void); 280 static inline void ipq_unlock(void); 281 282 static inline int 283 ipq_lock_try(void) 284 { 285 int s; 286 287 /* 288 * Use splvm() -- we're blocking things that would cause 289 * mbuf allocation. 290 */ 291 s = splvm(); 292 if (ipq_locked) { 293 splx(s); 294 return (0); 295 } 296 ipq_locked = 1; 297 splx(s); 298 return (1); 299 } 300 301 static inline void 302 ipq_unlock(void) 303 { 304 int s; 305 306 s = splvm(); 307 ipq_locked = 0; 308 splx(s); 309 } 310 311 #ifdef DIAGNOSTIC 312 #define IPQ_LOCK() \ 313 do { \ 314 if (ipq_lock_try() == 0) { \ 315 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 316 panic("ipq_lock"); \ 317 } \ 318 } while (/*CONSTCOND*/ 0) 319 #define IPQ_LOCK_CHECK() \ 320 do { \ 321 if (ipq_locked == 0) { \ 322 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 323 panic("ipq lock check"); \ 324 } \ 325 } while (/*CONSTCOND*/ 0) 326 #else 327 #define IPQ_LOCK() (void) ipq_lock_try() 328 #define IPQ_LOCK_CHECK() /* nothing */ 329 #endif 330 331 #define IPQ_UNLOCK() ipq_unlock() 332 333 struct pool inmulti_pool; 334 struct pool ipqent_pool; 335 336 #ifdef INET_CSUM_COUNTERS 337 #include <sys/device.h> 338 339 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 340 NULL, "inet", "hwcsum bad"); 341 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 342 NULL, "inet", "hwcsum ok"); 343 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 344 NULL, "inet", "swcsum"); 345 346 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 347 348 EVCNT_ATTACH_STATIC(ip_hwcsum_bad); 349 EVCNT_ATTACH_STATIC(ip_hwcsum_ok); 350 EVCNT_ATTACH_STATIC(ip_swcsum); 351 352 #else 353 354 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 355 356 #endif /* INET_CSUM_COUNTERS */ 357 358 /* 359 * We need to save the IP options in case a protocol wants to respond 360 * to an incoming packet over the same route if the packet got here 361 * using IP source routing. This allows connection establishment and 362 * maintenance when the remote end is on a network that is not known 363 * to us. 364 */ 365 int ip_nhops = 0; 366 static struct ip_srcrt { 367 struct in_addr dst; /* final destination */ 368 char nop; /* one NOP to align */ 369 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 370 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 371 } ip_srcrt; 372 373 static void save_rte(u_char *, struct in_addr); 374 375 #ifdef MBUFTRACE 376 struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx"); 377 struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx"); 378 #endif 379 380 /* 381 * Compute IP limits derived from the value of nmbclusters. 382 */ 383 static void 384 ip_nmbclusters_changed(void) 385 { 386 ip_maxfrags = nmbclusters / 4; 387 ip_nmbclusters = nmbclusters; 388 } 389 390 /* 391 * IP initialization: fill in IP protocol switch table. 392 * All protocols not implemented in kernel go to raw IP protocol handler. 393 */ 394 void 395 ip_init(void) 396 { 397 const struct protosw *pr; 398 int i; 399 400 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", 401 NULL, IPL_SOFTNET); 402 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 403 NULL, IPL_VM); 404 405 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 406 if (pr == 0) 407 panic("ip_init"); 408 for (i = 0; i < IPPROTO_MAX; i++) 409 ip_protox[i] = pr - inetsw; 410 for (pr = inetdomain.dom_protosw; 411 pr < inetdomain.dom_protoswNPROTOSW; pr++) 412 if (pr->pr_domain->dom_family == PF_INET && 413 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 414 ip_protox[pr->pr_protocol] = pr - inetsw; 415 416 for (i = 0; i < IPREASS_NHASH; i++) 417 LIST_INIT(&ipq[i]); 418 419 ip_initid(); 420 ip_id = time_second & 0xfffff; 421 422 ipintrq.ifq_maxlen = ipqmaxlen; 423 ip_nmbclusters_changed(); 424 425 TAILQ_INIT(&in_ifaddrhead); 426 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 427 &in_ifaddrhash); 428 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 429 &in_multihash); 430 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 431 #ifdef GATEWAY 432 ipflow_init(ip_hashsize); 433 #endif 434 435 #ifdef PFIL_HOOKS 436 /* Register our Packet Filter hook. */ 437 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 438 inet_pfil_hook.ph_af = AF_INET; 439 i = pfil_head_register(&inet_pfil_hook); 440 if (i != 0) 441 printf("ip_init: WARNING: unable to register pfil hook, " 442 "error %d\n", i); 443 #endif /* PFIL_HOOKS */ 444 445 #ifdef MBUFTRACE 446 MOWNER_ATTACH(&ip_tx_mowner); 447 MOWNER_ATTACH(&ip_rx_mowner); 448 #endif /* MBUFTRACE */ 449 450 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS); 451 } 452 453 struct sockaddr_in ipaddr = { 454 .sin_len = sizeof(ipaddr), 455 .sin_family = AF_INET, 456 }; 457 struct route ipforward_rt; 458 459 /* 460 * IP software interrupt routine 461 */ 462 void 463 ipintr(void) 464 { 465 int s; 466 struct mbuf *m; 467 468 mutex_enter(softnet_lock); 469 KERNEL_LOCK(1, NULL); 470 while (!IF_IS_EMPTY(&ipintrq)) { 471 s = splnet(); 472 IF_DEQUEUE(&ipintrq, m); 473 splx(s); 474 if (m == NULL) 475 break; 476 ip_input(m); 477 } 478 KERNEL_UNLOCK_ONE(NULL); 479 mutex_exit(softnet_lock); 480 } 481 482 /* 483 * Ip input routine. Checksum and byte swap header. If fragmented 484 * try to reassemble. Process options. Pass to next level. 485 */ 486 void 487 ip_input(struct mbuf *m) 488 { 489 struct ip *ip = NULL; 490 struct ipq *fp; 491 struct in_ifaddr *ia; 492 struct ifaddr *ifa; 493 struct ipqent *ipqe; 494 int hlen = 0, mff, len; 495 int downmatch; 496 int checkif; 497 int srcrt = 0; 498 int s; 499 u_int hash; 500 #ifdef FAST_IPSEC 501 struct m_tag *mtag; 502 struct tdb_ident *tdbi; 503 struct secpolicy *sp; 504 int error; 505 #endif /* FAST_IPSEC */ 506 507 MCLAIM(m, &ip_rx_mowner); 508 #ifdef DIAGNOSTIC 509 if ((m->m_flags & M_PKTHDR) == 0) 510 panic("ipintr no HDR"); 511 #endif 512 513 /* 514 * If no IP addresses have been set yet but the interfaces 515 * are receiving, can't do anything with incoming packets yet. 516 */ 517 if (TAILQ_FIRST(&in_ifaddrhead) == 0) 518 goto bad; 519 IP_STATINC(IP_STAT_TOTAL); 520 /* 521 * If the IP header is not aligned, slurp it up into a new 522 * mbuf with space for link headers, in the event we forward 523 * it. Otherwise, if it is aligned, make sure the entire 524 * base IP header is in the first mbuf of the chain. 525 */ 526 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) { 527 if ((m = m_copyup(m, sizeof(struct ip), 528 (max_linkhdr + 3) & ~3)) == NULL) { 529 /* XXXJRT new stat, please */ 530 IP_STATINC(IP_STAT_TOOSMALL); 531 return; 532 } 533 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 534 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 535 IP_STATINC(IP_STAT_TOOSMALL); 536 return; 537 } 538 } 539 ip = mtod(m, struct ip *); 540 if (ip->ip_v != IPVERSION) { 541 IP_STATINC(IP_STAT_BADVERS); 542 goto bad; 543 } 544 hlen = ip->ip_hl << 2; 545 if (hlen < sizeof(struct ip)) { /* minimum header length */ 546 IP_STATINC(IP_STAT_BADHLEN); 547 goto bad; 548 } 549 if (hlen > m->m_len) { 550 if ((m = m_pullup(m, hlen)) == 0) { 551 IP_STATINC(IP_STAT_BADHLEN); 552 return; 553 } 554 ip = mtod(m, struct ip *); 555 } 556 557 /* 558 * RFC1122: packets with a multicast source address are 559 * not allowed. 560 */ 561 if (IN_MULTICAST(ip->ip_src.s_addr)) { 562 IP_STATINC(IP_STAT_BADADDR); 563 goto bad; 564 } 565 566 /* 127/8 must not appear on wire - RFC1122 */ 567 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 568 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 569 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 570 IP_STATINC(IP_STAT_BADADDR); 571 goto bad; 572 } 573 } 574 575 switch (m->m_pkthdr.csum_flags & 576 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 577 M_CSUM_IPv4_BAD)) { 578 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 579 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 580 goto badcsum; 581 582 case M_CSUM_IPv4: 583 /* Checksum was okay. */ 584 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 585 break; 586 587 default: 588 /* 589 * Must compute it ourselves. Maybe skip checksum on 590 * loopback interfaces. 591 */ 592 if (__predict_true(!(m->m_pkthdr.rcvif->if_flags & 593 IFF_LOOPBACK) || ip_do_loopback_cksum)) { 594 INET_CSUM_COUNTER_INCR(&ip_swcsum); 595 if (in_cksum(m, hlen) != 0) 596 goto badcsum; 597 } 598 break; 599 } 600 601 /* Retrieve the packet length. */ 602 len = ntohs(ip->ip_len); 603 604 /* 605 * Check for additional length bogosity 606 */ 607 if (len < hlen) { 608 IP_STATINC(IP_STAT_BADLEN); 609 goto bad; 610 } 611 612 /* 613 * Check that the amount of data in the buffers 614 * is as at least much as the IP header would have us expect. 615 * Trim mbufs if longer than we expect. 616 * Drop packet if shorter than we expect. 617 */ 618 if (m->m_pkthdr.len < len) { 619 IP_STATINC(IP_STAT_TOOSHORT); 620 goto bad; 621 } 622 if (m->m_pkthdr.len > len) { 623 if (m->m_len == m->m_pkthdr.len) { 624 m->m_len = len; 625 m->m_pkthdr.len = len; 626 } else 627 m_adj(m, len - m->m_pkthdr.len); 628 } 629 630 #if defined(IPSEC) 631 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 632 m->m_flags &= ~M_CANFASTFWD; 633 #else 634 /* 635 * Assume that we can create a fast-forward IP flow entry 636 * based on this packet. 637 */ 638 m->m_flags |= M_CANFASTFWD; 639 #endif 640 641 #ifdef PFIL_HOOKS 642 /* 643 * Run through list of hooks for input packets. If there are any 644 * filters which require that additional packets in the flow are 645 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 646 * Note that filters must _never_ set this flag, as another filter 647 * in the list may have previously cleared it. 648 */ 649 /* 650 * let ipfilter look at packet on the wire, 651 * not the decapsulated packet. 652 */ 653 #ifdef IPSEC 654 if (!ipsec_getnhist(m)) 655 #elif defined(FAST_IPSEC) 656 if (!ipsec_indone(m)) 657 #else 658 if (1) 659 #endif 660 { 661 struct in_addr odst; 662 663 odst = ip->ip_dst; 664 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 665 PFIL_IN) != 0) 666 return; 667 if (m == NULL) 668 return; 669 ip = mtod(m, struct ip *); 670 hlen = ip->ip_hl << 2; 671 /* 672 * XXX The setting of "srcrt" here is to prevent ip_forward() 673 * from generating ICMP redirects for packets that have 674 * been redirected by a hook back out on to the same LAN that 675 * they came from and is not an indication that the packet 676 * is being inffluenced by source routing options. This 677 * allows things like 678 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp" 679 * where tlp0 is both on the 1.1.1.0/24 network and is the 680 * default route for hosts on 1.1.1.0/24. Of course this 681 * also requires a "map tlp0 ..." to complete the story. 682 * One might argue whether or not this kind of network config. 683 * should be supported in this manner... 684 */ 685 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 686 } 687 #endif /* PFIL_HOOKS */ 688 689 #ifdef ALTQ 690 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 691 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 692 /* packet dropped by traffic conditioner */ 693 return; 694 } 695 #endif 696 697 /* 698 * Process options and, if not destined for us, 699 * ship it on. ip_dooptions returns 1 when an 700 * error was detected (causing an icmp message 701 * to be sent and the original packet to be freed). 702 */ 703 ip_nhops = 0; /* for source routed packets */ 704 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 705 return; 706 707 /* 708 * Enable a consistency check between the destination address 709 * and the arrival interface for a unicast packet (the RFC 1122 710 * strong ES model) if IP forwarding is disabled and the packet 711 * is not locally generated. 712 * 713 * XXX - Checking also should be disabled if the destination 714 * address is ipnat'ed to a different interface. 715 * 716 * XXX - Checking is incompatible with IP aliases added 717 * to the loopback interface instead of the interface where 718 * the packets are received. 719 * 720 * XXX - We need to add a per ifaddr flag for this so that 721 * we get finer grain control. 722 */ 723 checkif = ip_checkinterface && (ipforwarding == 0) && 724 (m->m_pkthdr.rcvif != NULL) && 725 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 726 727 /* 728 * Check our list of addresses, to see if the packet is for us. 729 * 730 * Traditional 4.4BSD did not consult IFF_UP at all. 731 * The behavior here is to treat addresses on !IFF_UP interface 732 * as not mine. 733 */ 734 downmatch = 0; 735 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 736 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 737 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 738 continue; 739 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 740 break; 741 else 742 downmatch++; 743 } 744 } 745 if (ia != NULL) 746 goto ours; 747 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 748 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 749 if (ifa->ifa_addr->sa_family != AF_INET) 750 continue; 751 ia = ifatoia(ifa); 752 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 753 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 754 /* 755 * Look for all-0's host part (old broadcast addr), 756 * either for subnet or net. 757 */ 758 ip->ip_dst.s_addr == ia->ia_subnet || 759 ip->ip_dst.s_addr == ia->ia_net) 760 goto ours; 761 /* 762 * An interface with IP address zero accepts 763 * all packets that arrive on that interface. 764 */ 765 if (in_nullhost(ia->ia_addr.sin_addr)) 766 goto ours; 767 } 768 } 769 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 770 struct in_multi *inm; 771 #ifdef MROUTING 772 extern struct socket *ip_mrouter; 773 774 if (ip_mrouter) { 775 /* 776 * If we are acting as a multicast router, all 777 * incoming multicast packets are passed to the 778 * kernel-level multicast forwarding function. 779 * The packet is returned (relatively) intact; if 780 * ip_mforward() returns a non-zero value, the packet 781 * must be discarded, else it may be accepted below. 782 * 783 * (The IP ident field is put in the same byte order 784 * as expected when ip_mforward() is called from 785 * ip_output().) 786 */ 787 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 788 IP_STATINC(IP_STAT_CANTFORWARD); 789 m_freem(m); 790 return; 791 } 792 793 /* 794 * The process-level routing demon needs to receive 795 * all multicast IGMP packets, whether or not this 796 * host belongs to their destination groups. 797 */ 798 if (ip->ip_p == IPPROTO_IGMP) 799 goto ours; 800 IP_STATINC(IP_STAT_CANTFORWARD); 801 } 802 #endif 803 /* 804 * See if we belong to the destination multicast group on the 805 * arrival interface. 806 */ 807 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 808 if (inm == NULL) { 809 IP_STATINC(IP_STAT_CANTFORWARD); 810 m_freem(m); 811 return; 812 } 813 goto ours; 814 } 815 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 816 in_nullhost(ip->ip_dst)) 817 goto ours; 818 819 /* 820 * Not for us; forward if possible and desirable. 821 */ 822 if (ipforwarding == 0) { 823 IP_STATINC(IP_STAT_CANTFORWARD); 824 m_freem(m); 825 } else { 826 /* 827 * If ip_dst matched any of my address on !IFF_UP interface, 828 * and there's no IFF_UP interface that matches ip_dst, 829 * send icmp unreach. Forwarding it will result in in-kernel 830 * forwarding loop till TTL goes to 0. 831 */ 832 if (downmatch) { 833 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 834 IP_STATINC(IP_STAT_CANTFORWARD); 835 return; 836 } 837 #ifdef IPSEC 838 if (ipsec4_in_reject(m, NULL)) { 839 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 840 goto bad; 841 } 842 #endif 843 #ifdef FAST_IPSEC 844 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 845 s = splsoftnet(); 846 if (mtag != NULL) { 847 tdbi = (struct tdb_ident *)(mtag + 1); 848 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 849 } else { 850 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 851 IP_FORWARDING, &error); 852 } 853 if (sp == NULL) { /* NB: can happen if error */ 854 splx(s); 855 /*XXX error stat???*/ 856 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/ 857 goto bad; 858 } 859 860 /* 861 * Check security policy against packet attributes. 862 */ 863 error = ipsec_in_reject(sp, m); 864 KEY_FREESP(&sp); 865 splx(s); 866 if (error) { 867 IP_STATINC(IP_STAT_CANTFORWARD); 868 goto bad; 869 } 870 871 /* 872 * Peek at the outbound SP for this packet to determine if 873 * it's a Fast Forward candidate. 874 */ 875 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 876 if (mtag != NULL) 877 m->m_flags &= ~M_CANFASTFWD; 878 else { 879 s = splsoftnet(); 880 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, 881 (IP_FORWARDING | 882 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 883 &error, NULL); 884 if (sp != NULL) { 885 m->m_flags &= ~M_CANFASTFWD; 886 KEY_FREESP(&sp); 887 } 888 splx(s); 889 } 890 #endif /* FAST_IPSEC */ 891 892 ip_forward(m, srcrt); 893 } 894 return; 895 896 ours: 897 /* 898 * If offset or IP_MF are set, must reassemble. 899 * Otherwise, nothing need be done. 900 * (We could look in the reassembly queue to see 901 * if the packet was previously fragmented, 902 * but it's not worth the time; just let them time out.) 903 */ 904 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 905 uint16_t off; 906 /* 907 * Prevent TCP blind data attacks by not allowing non-initial 908 * fragments to start at less than 68 bytes (minimal fragment 909 * size) and making sure the first fragment is at least 68 910 * bytes. 911 */ 912 off = (ntohs(ip->ip_off) & IP_OFFMASK) << 3; 913 if ((off > 0 ? off + hlen : len) < IP_MINFRAGSIZE - 1) { 914 IP_STATINC(IP_STAT_BADFRAGS); 915 goto bad; 916 } 917 /* 918 * Look for queue of fragments 919 * of this datagram. 920 */ 921 IPQ_LOCK(); 922 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id); 923 LIST_FOREACH(fp, &ipq[hash], ipq_q) { 924 if (ip->ip_id == fp->ipq_id && 925 in_hosteq(ip->ip_src, fp->ipq_src) && 926 in_hosteq(ip->ip_dst, fp->ipq_dst) && 927 ip->ip_p == fp->ipq_p) { 928 /* 929 * Make sure the TOS is matches previous 930 * fragments. 931 */ 932 if (ip->ip_tos != fp->ipq_tos) { 933 IP_STATINC(IP_STAT_BADFRAGS); 934 IPQ_UNLOCK(); 935 goto bad; 936 } 937 goto found; 938 } 939 } 940 fp = 0; 941 found: 942 943 /* 944 * Adjust ip_len to not reflect header, 945 * set ipqe_mff if more fragments are expected, 946 * convert offset of this to bytes. 947 */ 948 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 949 mff = (ip->ip_off & htons(IP_MF)) != 0; 950 if (mff) { 951 /* 952 * Make sure that fragments have a data length 953 * that's a non-zero multiple of 8 bytes. 954 */ 955 if (ntohs(ip->ip_len) == 0 || 956 (ntohs(ip->ip_len) & 0x7) != 0) { 957 IP_STATINC(IP_STAT_BADFRAGS); 958 IPQ_UNLOCK(); 959 goto bad; 960 } 961 } 962 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 963 964 /* 965 * If datagram marked as having more fragments 966 * or if this is not the first fragment, 967 * attempt reassembly; if it succeeds, proceed. 968 */ 969 if (mff || ip->ip_off != htons(0)) { 970 IP_STATINC(IP_STAT_FRAGMENTS); 971 s = splvm(); 972 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 973 splx(s); 974 if (ipqe == NULL) { 975 IP_STATINC(IP_STAT_RCVMEMDROP); 976 IPQ_UNLOCK(); 977 goto bad; 978 } 979 ipqe->ipqe_mff = mff; 980 ipqe->ipqe_m = m; 981 ipqe->ipqe_ip = ip; 982 m = ip_reass(ipqe, fp, &ipq[hash]); 983 if (m == 0) { 984 IPQ_UNLOCK(); 985 return; 986 } 987 IP_STATINC(IP_STAT_REASSEMBLED); 988 ip = mtod(m, struct ip *); 989 hlen = ip->ip_hl << 2; 990 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 991 } else 992 if (fp) 993 ip_freef(fp); 994 IPQ_UNLOCK(); 995 } 996 997 #if defined(IPSEC) 998 /* 999 * enforce IPsec policy checking if we are seeing last header. 1000 * note that we do not visit this with protocols with pcb layer 1001 * code - like udp/tcp/raw ip. 1002 */ 1003 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 1004 ipsec4_in_reject(m, NULL)) { 1005 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1006 goto bad; 1007 } 1008 #endif 1009 #ifdef FAST_IPSEC 1010 /* 1011 * enforce IPsec policy checking if we are seeing last header. 1012 * note that we do not visit this with protocols with pcb layer 1013 * code - like udp/tcp/raw ip. 1014 */ 1015 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 1016 /* 1017 * Check if the packet has already had IPsec processing 1018 * done. If so, then just pass it along. This tag gets 1019 * set during AH, ESP, etc. input handling, before the 1020 * packet is returned to the ip input queue for delivery. 1021 */ 1022 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 1023 s = splsoftnet(); 1024 if (mtag != NULL) { 1025 tdbi = (struct tdb_ident *)(mtag + 1); 1026 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 1027 } else { 1028 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1029 IP_FORWARDING, &error); 1030 } 1031 if (sp != NULL) { 1032 /* 1033 * Check security policy against packet attributes. 1034 */ 1035 error = ipsec_in_reject(sp, m); 1036 KEY_FREESP(&sp); 1037 } else { 1038 /* XXX error stat??? */ 1039 error = EINVAL; 1040 DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 1041 } 1042 splx(s); 1043 if (error) 1044 goto bad; 1045 } 1046 #endif /* FAST_IPSEC */ 1047 1048 /* 1049 * Switch out to protocol's input routine. 1050 */ 1051 #if IFA_STATS 1052 if (ia && ip) 1053 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 1054 #endif 1055 IP_STATINC(IP_STAT_DELIVERED); 1056 { 1057 int off = hlen, nh = ip->ip_p; 1058 1059 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 1060 return; 1061 } 1062 bad: 1063 m_freem(m); 1064 return; 1065 1066 badcsum: 1067 IP_STATINC(IP_STAT_BADSUM); 1068 m_freem(m); 1069 } 1070 1071 /* 1072 * Take incoming datagram fragment and try to 1073 * reassemble it into whole datagram. If a chain for 1074 * reassembly of this datagram already exists, then it 1075 * is given as fp; otherwise have to make a chain. 1076 */ 1077 struct mbuf * 1078 ip_reass(struct ipqent *ipqe, struct ipq *fp, struct ipqhead *ipqhead) 1079 { 1080 struct mbuf *m = ipqe->ipqe_m; 1081 struct ipqent *nq, *p, *q; 1082 struct ip *ip; 1083 struct mbuf *t; 1084 int hlen = ipqe->ipqe_ip->ip_hl << 2; 1085 int i, next, s; 1086 1087 IPQ_LOCK_CHECK(); 1088 1089 /* 1090 * Presence of header sizes in mbufs 1091 * would confuse code below. 1092 */ 1093 m->m_data += hlen; 1094 m->m_len -= hlen; 1095 1096 #ifdef notyet 1097 /* make sure fragment limit is up-to-date */ 1098 CHECK_NMBCLUSTER_PARAMS(); 1099 1100 /* If we have too many fragments, drop the older half. */ 1101 if (ip_nfrags >= ip_maxfrags) 1102 ip_reass_drophalf(void); 1103 #endif 1104 1105 /* 1106 * We are about to add a fragment; increment frag count. 1107 */ 1108 ip_nfrags++; 1109 1110 /* 1111 * If first fragment to arrive, create a reassembly queue. 1112 */ 1113 if (fp == 0) { 1114 /* 1115 * Enforce upper bound on number of fragmented packets 1116 * for which we attempt reassembly; 1117 * If maxfrag is 0, never accept fragments. 1118 * If maxfrag is -1, accept all fragments without limitation. 1119 */ 1120 if (ip_maxfragpackets < 0) 1121 ; 1122 else if (ip_nfragpackets >= ip_maxfragpackets) 1123 goto dropfrag; 1124 ip_nfragpackets++; 1125 fp = malloc(sizeof (struct ipq), M_FTABLE, M_NOWAIT); 1126 if (fp == NULL) 1127 goto dropfrag; 1128 LIST_INSERT_HEAD(ipqhead, fp, ipq_q); 1129 fp->ipq_nfrags = 1; 1130 fp->ipq_ttl = IPFRAGTTL; 1131 fp->ipq_p = ipqe->ipqe_ip->ip_p; 1132 fp->ipq_id = ipqe->ipqe_ip->ip_id; 1133 fp->ipq_tos = ipqe->ipqe_ip->ip_tos; 1134 TAILQ_INIT(&fp->ipq_fragq); 1135 fp->ipq_src = ipqe->ipqe_ip->ip_src; 1136 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 1137 p = NULL; 1138 goto insert; 1139 } else { 1140 fp->ipq_nfrags++; 1141 } 1142 1143 /* 1144 * Find a segment which begins after this one does. 1145 */ 1146 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1147 p = q, q = TAILQ_NEXT(q, ipqe_q)) 1148 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 1149 break; 1150 1151 /* 1152 * If there is a preceding segment, it may provide some of 1153 * our data already. If so, drop the data from the incoming 1154 * segment. If it provides all of our data, drop us. 1155 */ 1156 if (p != NULL) { 1157 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 1158 ntohs(ipqe->ipqe_ip->ip_off); 1159 if (i > 0) { 1160 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 1161 goto dropfrag; 1162 m_adj(ipqe->ipqe_m, i); 1163 ipqe->ipqe_ip->ip_off = 1164 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 1165 ipqe->ipqe_ip->ip_len = 1166 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 1167 } 1168 } 1169 1170 /* 1171 * While we overlap succeeding segments trim them or, 1172 * if they are completely covered, dequeue them. 1173 */ 1174 for (; q != NULL && 1175 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 1176 ntohs(q->ipqe_ip->ip_off); q = nq) { 1177 i = (ntohs(ipqe->ipqe_ip->ip_off) + 1178 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 1179 if (i < ntohs(q->ipqe_ip->ip_len)) { 1180 q->ipqe_ip->ip_len = 1181 htons(ntohs(q->ipqe_ip->ip_len) - i); 1182 q->ipqe_ip->ip_off = 1183 htons(ntohs(q->ipqe_ip->ip_off) + i); 1184 m_adj(q->ipqe_m, i); 1185 break; 1186 } 1187 nq = TAILQ_NEXT(q, ipqe_q); 1188 m_freem(q->ipqe_m); 1189 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1190 s = splvm(); 1191 pool_put(&ipqent_pool, q); 1192 splx(s); 1193 fp->ipq_nfrags--; 1194 ip_nfrags--; 1195 } 1196 1197 insert: 1198 /* 1199 * Stick new segment in its place; 1200 * check for complete reassembly. 1201 */ 1202 if (p == NULL) { 1203 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1204 } else { 1205 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1206 } 1207 next = 0; 1208 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1209 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1210 if (ntohs(q->ipqe_ip->ip_off) != next) 1211 return (0); 1212 next += ntohs(q->ipqe_ip->ip_len); 1213 } 1214 if (p->ipqe_mff) 1215 return (0); 1216 1217 /* 1218 * Reassembly is complete. Check for a bogus message size and 1219 * concatenate fragments. 1220 */ 1221 q = TAILQ_FIRST(&fp->ipq_fragq); 1222 ip = q->ipqe_ip; 1223 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1224 IP_STATINC(IP_STAT_TOOLONG); 1225 ip_freef(fp); 1226 return (0); 1227 } 1228 m = q->ipqe_m; 1229 t = m->m_next; 1230 m->m_next = 0; 1231 m_cat(m, t); 1232 nq = TAILQ_NEXT(q, ipqe_q); 1233 s = splvm(); 1234 pool_put(&ipqent_pool, q); 1235 splx(s); 1236 for (q = nq; q != NULL; q = nq) { 1237 t = q->ipqe_m; 1238 nq = TAILQ_NEXT(q, ipqe_q); 1239 s = splvm(); 1240 pool_put(&ipqent_pool, q); 1241 splx(s); 1242 m_cat(m, t); 1243 } 1244 ip_nfrags -= fp->ipq_nfrags; 1245 1246 /* 1247 * Create header for new ip packet by 1248 * modifying header of first packet; 1249 * dequeue and discard fragment reassembly header. 1250 * Make header visible. 1251 */ 1252 ip->ip_len = htons(next); 1253 ip->ip_src = fp->ipq_src; 1254 ip->ip_dst = fp->ipq_dst; 1255 LIST_REMOVE(fp, ipq_q); 1256 free(fp, M_FTABLE); 1257 ip_nfragpackets--; 1258 m->m_len += (ip->ip_hl << 2); 1259 m->m_data -= (ip->ip_hl << 2); 1260 /* some debugging cruft by sklower, below, will go away soon */ 1261 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1262 int plen = 0; 1263 for (t = m; t; t = t->m_next) 1264 plen += t->m_len; 1265 m->m_pkthdr.len = plen; 1266 m->m_pkthdr.csum_flags = 0; 1267 } 1268 return (m); 1269 1270 dropfrag: 1271 if (fp != 0) 1272 fp->ipq_nfrags--; 1273 ip_nfrags--; 1274 IP_STATINC(IP_STAT_FRAGDROPPED); 1275 m_freem(m); 1276 s = splvm(); 1277 pool_put(&ipqent_pool, ipqe); 1278 splx(s); 1279 return (0); 1280 } 1281 1282 /* 1283 * Free a fragment reassembly header and all 1284 * associated datagrams. 1285 */ 1286 void 1287 ip_freef(struct ipq *fp) 1288 { 1289 struct ipqent *q, *p; 1290 u_int nfrags = 0; 1291 int s; 1292 1293 IPQ_LOCK_CHECK(); 1294 1295 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1296 p = TAILQ_NEXT(q, ipqe_q); 1297 m_freem(q->ipqe_m); 1298 nfrags++; 1299 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1300 s = splvm(); 1301 pool_put(&ipqent_pool, q); 1302 splx(s); 1303 } 1304 1305 if (nfrags != fp->ipq_nfrags) 1306 printf("ip_freef: nfrags %d != %d\n", fp->ipq_nfrags, nfrags); 1307 ip_nfrags -= nfrags; 1308 LIST_REMOVE(fp, ipq_q); 1309 free(fp, M_FTABLE); 1310 ip_nfragpackets--; 1311 } 1312 1313 /* 1314 * IP reassembly TTL machinery for multiplicative drop. 1315 */ 1316 static u_int fragttl_histo[(IPFRAGTTL+1)]; 1317 1318 1319 /* 1320 * Decrement TTL of all reasembly queue entries by `ticks'. 1321 * Count number of distinct fragments (as opposed to partial, fragmented 1322 * datagrams) in the reassembly queue. While we traverse the entire 1323 * reassembly queue, compute and return the median TTL over all fragments. 1324 */ 1325 static u_int 1326 ip_reass_ttl_decr(u_int ticks) 1327 { 1328 u_int nfrags, median, dropfraction, keepfraction; 1329 struct ipq *fp, *nfp; 1330 int i; 1331 1332 nfrags = 0; 1333 memset(fragttl_histo, 0, sizeof fragttl_histo); 1334 1335 for (i = 0; i < IPREASS_NHASH; i++) { 1336 for (fp = LIST_FIRST(&ipq[i]); fp != NULL; fp = nfp) { 1337 fp->ipq_ttl = ((fp->ipq_ttl <= ticks) ? 1338 0 : fp->ipq_ttl - ticks); 1339 nfp = LIST_NEXT(fp, ipq_q); 1340 if (fp->ipq_ttl == 0) { 1341 IP_STATINC(IP_STAT_FRAGTIMEOUT); 1342 ip_freef(fp); 1343 } else { 1344 nfrags += fp->ipq_nfrags; 1345 fragttl_histo[fp->ipq_ttl] += fp->ipq_nfrags; 1346 } 1347 } 1348 } 1349 1350 KASSERT(ip_nfrags == nfrags); 1351 1352 /* Find median (or other drop fraction) in histogram. */ 1353 dropfraction = (ip_nfrags / 2); 1354 keepfraction = ip_nfrags - dropfraction; 1355 for (i = IPFRAGTTL, median = 0; i >= 0; i--) { 1356 median += fragttl_histo[i]; 1357 if (median >= keepfraction) 1358 break; 1359 } 1360 1361 /* Return TTL of median (or other fraction). */ 1362 return (u_int)i; 1363 } 1364 1365 void 1366 ip_reass_drophalf(void) 1367 { 1368 1369 u_int median_ticks; 1370 /* 1371 * Compute median TTL of all fragments, and count frags 1372 * with that TTL or lower (roughly half of all fragments). 1373 */ 1374 median_ticks = ip_reass_ttl_decr(0); 1375 1376 /* Drop half. */ 1377 median_ticks = ip_reass_ttl_decr(median_ticks); 1378 1379 } 1380 1381 /* 1382 * IP timer processing; 1383 * if a timer expires on a reassembly 1384 * queue, discard it. 1385 */ 1386 void 1387 ip_slowtimo(void) 1388 { 1389 static u_int dropscanidx = 0; 1390 u_int i; 1391 u_int median_ttl; 1392 1393 mutex_enter(softnet_lock); 1394 KERNEL_LOCK(1, NULL); 1395 1396 IPQ_LOCK(); 1397 1398 /* Age TTL of all fragments by 1 tick .*/ 1399 median_ttl = ip_reass_ttl_decr(1); 1400 1401 /* make sure fragment limit is up-to-date */ 1402 CHECK_NMBCLUSTER_PARAMS(); 1403 1404 /* If we have too many fragments, drop the older half. */ 1405 if (ip_nfrags > ip_maxfrags) 1406 ip_reass_ttl_decr(median_ttl); 1407 1408 /* 1409 * If we are over the maximum number of fragmented packets 1410 * (due to the limit being lowered), drain off 1411 * enough to get down to the new limit. Start draining 1412 * from the reassembly hashqueue most recently drained. 1413 */ 1414 if (ip_maxfragpackets < 0) 1415 ; 1416 else { 1417 int wrapped = 0; 1418 1419 i = dropscanidx; 1420 while (ip_nfragpackets > ip_maxfragpackets && wrapped == 0) { 1421 while (LIST_FIRST(&ipq[i]) != NULL) 1422 ip_freef(LIST_FIRST(&ipq[i])); 1423 if (++i >= IPREASS_NHASH) { 1424 i = 0; 1425 } 1426 /* 1427 * Dont scan forever even if fragment counters are 1428 * wrong: stop after scanning entire reassembly queue. 1429 */ 1430 if (i == dropscanidx) 1431 wrapped = 1; 1432 } 1433 dropscanidx = i; 1434 } 1435 IPQ_UNLOCK(); 1436 1437 KERNEL_UNLOCK_ONE(NULL); 1438 mutex_exit(softnet_lock); 1439 } 1440 1441 /* 1442 * Drain off all datagram fragments. Don't acquire softnet_lock as 1443 * can be called from hardware interrupt context. 1444 */ 1445 void 1446 ip_drain(void) 1447 { 1448 1449 KERNEL_LOCK(1, NULL); 1450 1451 /* 1452 * We may be called from a device's interrupt context. If 1453 * the ipq is already busy, just bail out now. 1454 */ 1455 if (ipq_lock_try() != 0) { 1456 /* 1457 * Drop half the total fragments now. If more mbufs are 1458 * needed, we will be called again soon. 1459 */ 1460 ip_reass_drophalf(); 1461 IPQ_UNLOCK(); 1462 } 1463 1464 KERNEL_UNLOCK_ONE(NULL); 1465 } 1466 1467 /* 1468 * Do option processing on a datagram, 1469 * possibly discarding it if bad options are encountered, 1470 * or forwarding it if source-routed. 1471 * Returns 1 if packet has been forwarded/freed, 1472 * 0 if the packet should be processed further. 1473 */ 1474 int 1475 ip_dooptions(struct mbuf *m) 1476 { 1477 struct ip *ip = mtod(m, struct ip *); 1478 u_char *cp, *cp0; 1479 struct ip_timestamp *ipt; 1480 struct in_ifaddr *ia; 1481 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1482 struct in_addr dst; 1483 n_time ntime; 1484 1485 dst = ip->ip_dst; 1486 cp = (u_char *)(ip + 1); 1487 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1488 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1489 opt = cp[IPOPT_OPTVAL]; 1490 if (opt == IPOPT_EOL) 1491 break; 1492 if (opt == IPOPT_NOP) 1493 optlen = 1; 1494 else { 1495 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1496 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1497 goto bad; 1498 } 1499 optlen = cp[IPOPT_OLEN]; 1500 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1501 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1502 goto bad; 1503 } 1504 } 1505 switch (opt) { 1506 1507 default: 1508 break; 1509 1510 /* 1511 * Source routing with record. 1512 * Find interface with current destination address. 1513 * If none on this machine then drop if strictly routed, 1514 * or do nothing if loosely routed. 1515 * Record interface address and bring up next address 1516 * component. If strictly routed make sure next 1517 * address is on directly accessible net. 1518 */ 1519 case IPOPT_LSRR: 1520 case IPOPT_SSRR: 1521 if (ip_allowsrcrt == 0) { 1522 type = ICMP_UNREACH; 1523 code = ICMP_UNREACH_NET_PROHIB; 1524 goto bad; 1525 } 1526 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1527 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1528 goto bad; 1529 } 1530 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1531 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1532 goto bad; 1533 } 1534 ipaddr.sin_addr = ip->ip_dst; 1535 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1536 if (ia == 0) { 1537 if (opt == IPOPT_SSRR) { 1538 type = ICMP_UNREACH; 1539 code = ICMP_UNREACH_SRCFAIL; 1540 goto bad; 1541 } 1542 /* 1543 * Loose routing, and not at next destination 1544 * yet; nothing to do except forward. 1545 */ 1546 break; 1547 } 1548 off--; /* 0 origin */ 1549 if ((off + sizeof(struct in_addr)) > optlen) { 1550 /* 1551 * End of source route. Should be for us. 1552 */ 1553 save_rte(cp, ip->ip_src); 1554 break; 1555 } 1556 /* 1557 * locate outgoing interface 1558 */ 1559 bcopy((void *)(cp + off), (void *)&ipaddr.sin_addr, 1560 sizeof(ipaddr.sin_addr)); 1561 if (opt == IPOPT_SSRR) 1562 ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr))); 1563 else 1564 ia = ip_rtaddr(ipaddr.sin_addr); 1565 if (ia == 0) { 1566 type = ICMP_UNREACH; 1567 code = ICMP_UNREACH_SRCFAIL; 1568 goto bad; 1569 } 1570 ip->ip_dst = ipaddr.sin_addr; 1571 bcopy((void *)&ia->ia_addr.sin_addr, 1572 (void *)(cp + off), sizeof(struct in_addr)); 1573 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1574 /* 1575 * Let ip_intr's mcast routing check handle mcast pkts 1576 */ 1577 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1578 break; 1579 1580 case IPOPT_RR: 1581 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1582 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1583 goto bad; 1584 } 1585 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1586 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1587 goto bad; 1588 } 1589 /* 1590 * If no space remains, ignore. 1591 */ 1592 off--; /* 0 origin */ 1593 if ((off + sizeof(struct in_addr)) > optlen) 1594 break; 1595 bcopy((void *)(&ip->ip_dst), (void *)&ipaddr.sin_addr, 1596 sizeof(ipaddr.sin_addr)); 1597 /* 1598 * locate outgoing interface; if we're the destination, 1599 * use the incoming interface (should be same). 1600 */ 1601 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1602 == NULL && 1603 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1604 type = ICMP_UNREACH; 1605 code = ICMP_UNREACH_HOST; 1606 goto bad; 1607 } 1608 bcopy((void *)&ia->ia_addr.sin_addr, 1609 (void *)(cp + off), sizeof(struct in_addr)); 1610 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1611 break; 1612 1613 case IPOPT_TS: 1614 code = cp - (u_char *)ip; 1615 ipt = (struct ip_timestamp *)cp; 1616 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1617 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1618 goto bad; 1619 } 1620 if (ipt->ipt_ptr < 5) { 1621 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1622 goto bad; 1623 } 1624 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1625 if (++ipt->ipt_oflw == 0) { 1626 code = (u_char *)&ipt->ipt_ptr - 1627 (u_char *)ip; 1628 goto bad; 1629 } 1630 break; 1631 } 1632 cp0 = (cp + ipt->ipt_ptr - 1); 1633 switch (ipt->ipt_flg) { 1634 1635 case IPOPT_TS_TSONLY: 1636 break; 1637 1638 case IPOPT_TS_TSANDADDR: 1639 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1640 sizeof(struct in_addr) > ipt->ipt_len) { 1641 code = (u_char *)&ipt->ipt_ptr - 1642 (u_char *)ip; 1643 goto bad; 1644 } 1645 ipaddr.sin_addr = dst; 1646 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1647 m->m_pkthdr.rcvif)); 1648 if (ia == 0) 1649 continue; 1650 bcopy(&ia->ia_addr.sin_addr, 1651 cp0, sizeof(struct in_addr)); 1652 ipt->ipt_ptr += sizeof(struct in_addr); 1653 break; 1654 1655 case IPOPT_TS_PRESPEC: 1656 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1657 sizeof(struct in_addr) > ipt->ipt_len) { 1658 code = (u_char *)&ipt->ipt_ptr - 1659 (u_char *)ip; 1660 goto bad; 1661 } 1662 bcopy(cp0, &ipaddr.sin_addr, 1663 sizeof(struct in_addr)); 1664 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1665 == NULL) 1666 continue; 1667 ipt->ipt_ptr += sizeof(struct in_addr); 1668 break; 1669 1670 default: 1671 /* XXX can't take &ipt->ipt_flg */ 1672 code = (u_char *)&ipt->ipt_ptr - 1673 (u_char *)ip + 1; 1674 goto bad; 1675 } 1676 ntime = iptime(); 1677 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1678 memmove((char *)cp + ipt->ipt_ptr - 1, cp0, 1679 sizeof(n_time)); 1680 ipt->ipt_ptr += sizeof(n_time); 1681 } 1682 } 1683 if (forward) { 1684 if (ip_forwsrcrt == 0) { 1685 type = ICMP_UNREACH; 1686 code = ICMP_UNREACH_SRCFAIL; 1687 goto bad; 1688 } 1689 ip_forward(m, 1); 1690 return (1); 1691 } 1692 return (0); 1693 bad: 1694 icmp_error(m, type, code, 0, 0); 1695 IP_STATINC(IP_STAT_BADOPTIONS); 1696 return (1); 1697 } 1698 1699 /* 1700 * Given address of next destination (final or next hop), 1701 * return internet address info of interface to be used to get there. 1702 */ 1703 struct in_ifaddr * 1704 ip_rtaddr(struct in_addr dst) 1705 { 1706 struct rtentry *rt; 1707 union { 1708 struct sockaddr dst; 1709 struct sockaddr_in dst4; 1710 } u; 1711 1712 sockaddr_in_init(&u.dst4, &dst, 0); 1713 1714 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) 1715 return NULL; 1716 1717 return ifatoia(rt->rt_ifa); 1718 } 1719 1720 /* 1721 * Save incoming source route for use in replies, 1722 * to be picked up later by ip_srcroute if the receiver is interested. 1723 */ 1724 void 1725 save_rte(u_char *option, struct in_addr dst) 1726 { 1727 unsigned olen; 1728 1729 olen = option[IPOPT_OLEN]; 1730 #ifdef DIAGNOSTIC 1731 if (ipprintfs) 1732 printf("save_rte: olen %d\n", olen); 1733 #endif /* 0 */ 1734 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1735 return; 1736 bcopy((void *)option, (void *)ip_srcrt.srcopt, olen); 1737 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1738 ip_srcrt.dst = dst; 1739 } 1740 1741 /* 1742 * Retrieve incoming source route for use in replies, 1743 * in the same form used by setsockopt. 1744 * The first hop is placed before the options, will be removed later. 1745 */ 1746 struct mbuf * 1747 ip_srcroute(void) 1748 { 1749 struct in_addr *p, *q; 1750 struct mbuf *m; 1751 1752 if (ip_nhops == 0) 1753 return NULL; 1754 m = m_get(M_DONTWAIT, MT_SOOPTS); 1755 if (m == 0) 1756 return NULL; 1757 1758 MCLAIM(m, &inetdomain.dom_mowner); 1759 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1760 1761 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1762 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1763 OPTSIZ; 1764 #ifdef DIAGNOSTIC 1765 if (ipprintfs) 1766 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1767 #endif 1768 1769 /* 1770 * First save first hop for return route 1771 */ 1772 p = &ip_srcrt.route[ip_nhops - 1]; 1773 *(mtod(m, struct in_addr *)) = *p--; 1774 #ifdef DIAGNOSTIC 1775 if (ipprintfs) 1776 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1777 #endif 1778 1779 /* 1780 * Copy option fields and padding (nop) to mbuf. 1781 */ 1782 ip_srcrt.nop = IPOPT_NOP; 1783 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1784 memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop, 1785 OPTSIZ); 1786 q = (struct in_addr *)(mtod(m, char *) + 1787 sizeof(struct in_addr) + OPTSIZ); 1788 #undef OPTSIZ 1789 /* 1790 * Record return path as an IP source route, 1791 * reversing the path (pointers are now aligned). 1792 */ 1793 while (p >= ip_srcrt.route) { 1794 #ifdef DIAGNOSTIC 1795 if (ipprintfs) 1796 printf(" %x", ntohl(q->s_addr)); 1797 #endif 1798 *q++ = *p--; 1799 } 1800 /* 1801 * Last hop goes to final destination. 1802 */ 1803 *q = ip_srcrt.dst; 1804 #ifdef DIAGNOSTIC 1805 if (ipprintfs) 1806 printf(" %x\n", ntohl(q->s_addr)); 1807 #endif 1808 return (m); 1809 } 1810 1811 const int inetctlerrmap[PRC_NCMDS] = { 1812 [PRC_MSGSIZE] = EMSGSIZE, 1813 [PRC_HOSTDEAD] = EHOSTDOWN, 1814 [PRC_HOSTUNREACH] = EHOSTUNREACH, 1815 [PRC_UNREACH_NET] = EHOSTUNREACH, 1816 [PRC_UNREACH_HOST] = EHOSTUNREACH, 1817 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED, 1818 [PRC_UNREACH_PORT] = ECONNREFUSED, 1819 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH, 1820 [PRC_PARAMPROB] = ENOPROTOOPT, 1821 }; 1822 1823 /* 1824 * Forward a packet. If some error occurs return the sender 1825 * an icmp packet. Note we can't always generate a meaningful 1826 * icmp message because icmp doesn't have a large enough repertoire 1827 * of codes and types. 1828 * 1829 * If not forwarding, just drop the packet. This could be confusing 1830 * if ipforwarding was zero but some routing protocol was advancing 1831 * us as a gateway to somewhere. However, we must let the routing 1832 * protocol deal with that. 1833 * 1834 * The srcrt parameter indicates whether the packet is being forwarded 1835 * via a source route. 1836 */ 1837 void 1838 ip_forward(struct mbuf *m, int srcrt) 1839 { 1840 struct ip *ip = mtod(m, struct ip *); 1841 struct rtentry *rt; 1842 int error, type = 0, code = 0, destmtu = 0; 1843 struct mbuf *mcopy; 1844 n_long dest; 1845 union { 1846 struct sockaddr dst; 1847 struct sockaddr_in dst4; 1848 } u; 1849 1850 /* 1851 * We are now in the output path. 1852 */ 1853 MCLAIM(m, &ip_tx_mowner); 1854 1855 /* 1856 * Clear any in-bound checksum flags for this packet. 1857 */ 1858 m->m_pkthdr.csum_flags = 0; 1859 1860 dest = 0; 1861 #ifdef DIAGNOSTIC 1862 if (ipprintfs) { 1863 printf("forward: src %s ", inet_ntoa(ip->ip_src)); 1864 printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl); 1865 } 1866 #endif 1867 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1868 IP_STATINC(IP_STAT_CANTFORWARD); 1869 m_freem(m); 1870 return; 1871 } 1872 if (ip->ip_ttl <= IPTTLDEC) { 1873 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1874 return; 1875 } 1876 1877 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0); 1878 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) { 1879 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0); 1880 return; 1881 } 1882 1883 /* 1884 * Save at most 68 bytes of the packet in case 1885 * we need to generate an ICMP message to the src. 1886 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1887 */ 1888 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1889 if (mcopy) 1890 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1891 1892 ip->ip_ttl -= IPTTLDEC; 1893 1894 /* 1895 * If forwarding packet using same interface that it came in on, 1896 * perhaps should send a redirect to sender to shortcut a hop. 1897 * Only send redirect if source is sending directly to us, 1898 * and if packet was not source routed (or has any options). 1899 * Also, don't send redirect if forwarding using a default route 1900 * or a route modified by a redirect. 1901 */ 1902 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1903 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1904 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) && 1905 ipsendredirects && !srcrt) { 1906 if (rt->rt_ifa && 1907 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1908 ifatoia(rt->rt_ifa)->ia_subnet) { 1909 if (rt->rt_flags & RTF_GATEWAY) 1910 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1911 else 1912 dest = ip->ip_dst.s_addr; 1913 /* 1914 * Router requirements says to only send host 1915 * redirects. 1916 */ 1917 type = ICMP_REDIRECT; 1918 code = ICMP_REDIRECT_HOST; 1919 #ifdef DIAGNOSTIC 1920 if (ipprintfs) 1921 printf("redirect (%d) to %x\n", code, 1922 (u_int32_t)dest); 1923 #endif 1924 } 1925 } 1926 1927 error = ip_output(m, NULL, &ipforward_rt, 1928 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1929 (struct ip_moptions *)NULL, (struct socket *)NULL); 1930 1931 if (error) 1932 IP_STATINC(IP_STAT_CANTFORWARD); 1933 else { 1934 uint64_t *ips = IP_STAT_GETREF(); 1935 ips[IP_STAT_FORWARD]++; 1936 if (type) { 1937 ips[IP_STAT_REDIRECTSENT]++; 1938 IP_STAT_PUTREF(); 1939 } else { 1940 IP_STAT_PUTREF(); 1941 if (mcopy) { 1942 #ifdef GATEWAY 1943 if (mcopy->m_flags & M_CANFASTFWD) 1944 ipflow_create(&ipforward_rt, mcopy); 1945 #endif 1946 m_freem(mcopy); 1947 } 1948 return; 1949 } 1950 } 1951 if (mcopy == NULL) 1952 return; 1953 1954 switch (error) { 1955 1956 case 0: /* forwarded, but need redirect */ 1957 /* type, code set above */ 1958 break; 1959 1960 case ENETUNREACH: /* shouldn't happen, checked above */ 1961 case EHOSTUNREACH: 1962 case ENETDOWN: 1963 case EHOSTDOWN: 1964 default: 1965 type = ICMP_UNREACH; 1966 code = ICMP_UNREACH_HOST; 1967 break; 1968 1969 case EMSGSIZE: 1970 type = ICMP_UNREACH; 1971 code = ICMP_UNREACH_NEEDFRAG; 1972 1973 if ((rt = rtcache_validate(&ipforward_rt)) != NULL) 1974 destmtu = rt->rt_ifp->if_mtu; 1975 1976 #if defined(IPSEC) || defined(FAST_IPSEC) 1977 { 1978 /* 1979 * If the packet is routed over IPsec tunnel, tell the 1980 * originator the tunnel MTU. 1981 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1982 * XXX quickhack!!! 1983 */ 1984 1985 struct secpolicy *sp; 1986 int ipsecerror; 1987 size_t ipsechdr; 1988 struct route *ro; 1989 1990 sp = ipsec4_getpolicybyaddr(mcopy, 1991 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1992 &ipsecerror); 1993 1994 if (sp != NULL) { 1995 /* count IPsec header size */ 1996 ipsechdr = ipsec4_hdrsiz(mcopy, 1997 IPSEC_DIR_OUTBOUND, NULL); 1998 1999 /* 2000 * find the correct route for outer IPv4 2001 * header, compute tunnel MTU. 2002 */ 2003 2004 if (sp->req != NULL 2005 && sp->req->sav != NULL 2006 && sp->req->sav->sah != NULL) { 2007 ro = &sp->req->sav->sah->sa_route; 2008 rt = rtcache_validate(ro); 2009 if (rt && rt->rt_ifp) { 2010 destmtu = 2011 rt->rt_rmx.rmx_mtu ? 2012 rt->rt_rmx.rmx_mtu : 2013 rt->rt_ifp->if_mtu; 2014 destmtu -= ipsechdr; 2015 } 2016 } 2017 2018 #ifdef IPSEC 2019 key_freesp(sp); 2020 #else 2021 KEY_FREESP(&sp); 2022 #endif 2023 } 2024 } 2025 #endif /*defined(IPSEC) || defined(FAST_IPSEC)*/ 2026 IP_STATINC(IP_STAT_CANTFRAG); 2027 break; 2028 2029 case ENOBUFS: 2030 #if 1 2031 /* 2032 * a router should not generate ICMP_SOURCEQUENCH as 2033 * required in RFC1812 Requirements for IP Version 4 Routers. 2034 * source quench could be a big problem under DoS attacks, 2035 * or if the underlying interface is rate-limited. 2036 */ 2037 if (mcopy) 2038 m_freem(mcopy); 2039 return; 2040 #else 2041 type = ICMP_SOURCEQUENCH; 2042 code = 0; 2043 break; 2044 #endif 2045 } 2046 icmp_error(mcopy, type, code, dest, destmtu); 2047 } 2048 2049 void 2050 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 2051 struct mbuf *m) 2052 { 2053 2054 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 2055 struct timeval tv; 2056 2057 microtime(&tv); 2058 *mp = sbcreatecontrol((void *) &tv, sizeof(tv), 2059 SCM_TIMESTAMP, SOL_SOCKET); 2060 if (*mp) 2061 mp = &(*mp)->m_next; 2062 } 2063 if (inp->inp_flags & INP_RECVDSTADDR) { 2064 *mp = sbcreatecontrol((void *) &ip->ip_dst, 2065 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 2066 if (*mp) 2067 mp = &(*mp)->m_next; 2068 } 2069 #ifdef notyet 2070 /* 2071 * XXX 2072 * Moving these out of udp_input() made them even more broken 2073 * than they already were. 2074 * - fenner@parc.xerox.com 2075 */ 2076 /* options were tossed already */ 2077 if (inp->inp_flags & INP_RECVOPTS) { 2078 *mp = sbcreatecontrol((void *) opts_deleted_above, 2079 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 2080 if (*mp) 2081 mp = &(*mp)->m_next; 2082 } 2083 /* ip_srcroute doesn't do what we want here, need to fix */ 2084 if (inp->inp_flags & INP_RECVRETOPTS) { 2085 *mp = sbcreatecontrol((void *) ip_srcroute(), 2086 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 2087 if (*mp) 2088 mp = &(*mp)->m_next; 2089 } 2090 #endif 2091 if (inp->inp_flags & INP_RECVIF) { 2092 struct sockaddr_dl sdl; 2093 2094 sockaddr_dl_init(&sdl, sizeof(sdl), 2095 (m->m_pkthdr.rcvif != NULL) 2096 ? m->m_pkthdr.rcvif->if_index 2097 : 0, 2098 0, NULL, 0, NULL, 0); 2099 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP); 2100 if (*mp) 2101 mp = &(*mp)->m_next; 2102 } 2103 } 2104 2105 /* 2106 * sysctl helper routine for net.inet.ip.forwsrcrt. 2107 */ 2108 static int 2109 sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS) 2110 { 2111 int error, tmp; 2112 struct sysctlnode node; 2113 2114 node = *rnode; 2115 tmp = ip_forwsrcrt; 2116 node.sysctl_data = &tmp; 2117 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2118 if (error || newp == NULL) 2119 return (error); 2120 2121 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT, 2122 0, NULL, NULL, NULL)) 2123 return (EPERM); 2124 2125 ip_forwsrcrt = tmp; 2126 2127 return (0); 2128 } 2129 2130 /* 2131 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the 2132 * range of the new value and tweaks timers if it changes. 2133 */ 2134 static int 2135 sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS) 2136 { 2137 int error, tmp; 2138 struct sysctlnode node; 2139 2140 node = *rnode; 2141 tmp = ip_mtudisc_timeout; 2142 node.sysctl_data = &tmp; 2143 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2144 if (error || newp == NULL) 2145 return (error); 2146 if (tmp < 0) 2147 return (EINVAL); 2148 2149 mutex_enter(softnet_lock); 2150 2151 ip_mtudisc_timeout = tmp; 2152 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 2153 2154 mutex_exit(softnet_lock); 2155 2156 return (0); 2157 } 2158 2159 #ifdef GATEWAY 2160 /* 2161 * sysctl helper routine for net.inet.ip.maxflows. 2162 */ 2163 static int 2164 sysctl_net_inet_ip_maxflows(SYSCTLFN_ARGS) 2165 { 2166 int error; 2167 2168 error = sysctl_lookup(SYSCTLFN_CALL(rnode)); 2169 if (error || newp == NULL) 2170 return (error); 2171 2172 mutex_enter(softnet_lock); 2173 KERNEL_LOCK(1, NULL); 2174 2175 ipflow_prune(); 2176 2177 KERNEL_UNLOCK_ONE(NULL); 2178 mutex_exit(softnet_lock); 2179 2180 return (0); 2181 } 2182 2183 static int 2184 sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS) 2185 { 2186 int error, tmp; 2187 struct sysctlnode node; 2188 2189 node = *rnode; 2190 tmp = ip_hashsize; 2191 node.sysctl_data = &tmp; 2192 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2193 if (error || newp == NULL) 2194 return (error); 2195 2196 if ((tmp & (tmp - 1)) == 0 && tmp != 0) { 2197 /* 2198 * Can only fail due to malloc() 2199 */ 2200 mutex_enter(softnet_lock); 2201 KERNEL_LOCK(1, NULL); 2202 2203 error = ipflow_invalidate_all(tmp); 2204 2205 KERNEL_UNLOCK_ONE(NULL); 2206 mutex_exit(softnet_lock); 2207 2208 } else { 2209 /* 2210 * EINVAL if not a power of 2 2211 */ 2212 error = EINVAL; 2213 } 2214 2215 return error; 2216 } 2217 #endif /* GATEWAY */ 2218 2219 static int 2220 sysctl_net_inet_ip_stats(SYSCTLFN_ARGS) 2221 { 2222 2223 return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS)); 2224 } 2225 2226 SYSCTL_SETUP(sysctl_net_inet_ip_setup, "sysctl net.inet.ip subtree setup") 2227 { 2228 extern int subnetsarelocal, hostzeroisbroadcast; 2229 2230 sysctl_createv(clog, 0, NULL, NULL, 2231 CTLFLAG_PERMANENT, 2232 CTLTYPE_NODE, "net", NULL, 2233 NULL, 0, NULL, 0, 2234 CTL_NET, CTL_EOL); 2235 sysctl_createv(clog, 0, NULL, NULL, 2236 CTLFLAG_PERMANENT, 2237 CTLTYPE_NODE, "inet", 2238 SYSCTL_DESCR("PF_INET related settings"), 2239 NULL, 0, NULL, 0, 2240 CTL_NET, PF_INET, CTL_EOL); 2241 sysctl_createv(clog, 0, NULL, NULL, 2242 CTLFLAG_PERMANENT, 2243 CTLTYPE_NODE, "ip", 2244 SYSCTL_DESCR("IPv4 related settings"), 2245 NULL, 0, NULL, 0, 2246 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL); 2247 2248 sysctl_createv(clog, 0, NULL, NULL, 2249 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2250 CTLTYPE_INT, "forwarding", 2251 SYSCTL_DESCR("Enable forwarding of INET datagrams"), 2252 NULL, 0, &ipforwarding, 0, 2253 CTL_NET, PF_INET, IPPROTO_IP, 2254 IPCTL_FORWARDING, CTL_EOL); 2255 sysctl_createv(clog, 0, NULL, NULL, 2256 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2257 CTLTYPE_INT, "redirect", 2258 SYSCTL_DESCR("Enable sending of ICMP redirect messages"), 2259 NULL, 0, &ipsendredirects, 0, 2260 CTL_NET, PF_INET, IPPROTO_IP, 2261 IPCTL_SENDREDIRECTS, CTL_EOL); 2262 sysctl_createv(clog, 0, NULL, NULL, 2263 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2264 CTLTYPE_INT, "ttl", 2265 SYSCTL_DESCR("Default TTL for an INET datagram"), 2266 NULL, 0, &ip_defttl, 0, 2267 CTL_NET, PF_INET, IPPROTO_IP, 2268 IPCTL_DEFTTL, CTL_EOL); 2269 #ifdef IPCTL_DEFMTU 2270 sysctl_createv(clog, 0, NULL, NULL, 2271 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */, 2272 CTLTYPE_INT, "mtu", 2273 SYSCTL_DESCR("Default MTA for an INET route"), 2274 NULL, 0, &ip_mtu, 0, 2275 CTL_NET, PF_INET, IPPROTO_IP, 2276 IPCTL_DEFMTU, CTL_EOL); 2277 #endif /* IPCTL_DEFMTU */ 2278 sysctl_createv(clog, 0, NULL, NULL, 2279 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2280 CTLTYPE_INT, "forwsrcrt", 2281 SYSCTL_DESCR("Enable forwarding of source-routed " 2282 "datagrams"), 2283 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0, 2284 CTL_NET, PF_INET, IPPROTO_IP, 2285 IPCTL_FORWSRCRT, CTL_EOL); 2286 sysctl_createv(clog, 0, NULL, NULL, 2287 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2288 CTLTYPE_INT, "directed-broadcast", 2289 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"), 2290 NULL, 0, &ip_directedbcast, 0, 2291 CTL_NET, PF_INET, IPPROTO_IP, 2292 IPCTL_DIRECTEDBCAST, CTL_EOL); 2293 sysctl_createv(clog, 0, NULL, NULL, 2294 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2295 CTLTYPE_INT, "allowsrcrt", 2296 SYSCTL_DESCR("Accept source-routed datagrams"), 2297 NULL, 0, &ip_allowsrcrt, 0, 2298 CTL_NET, PF_INET, IPPROTO_IP, 2299 IPCTL_ALLOWSRCRT, CTL_EOL); 2300 sysctl_createv(clog, 0, NULL, NULL, 2301 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2302 CTLTYPE_INT, "subnetsarelocal", 2303 SYSCTL_DESCR("Whether logical subnets are considered " 2304 "local"), 2305 NULL, 0, &subnetsarelocal, 0, 2306 CTL_NET, PF_INET, IPPROTO_IP, 2307 IPCTL_SUBNETSARELOCAL, CTL_EOL); 2308 sysctl_createv(clog, 0, NULL, NULL, 2309 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2310 CTLTYPE_INT, "mtudisc", 2311 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"), 2312 NULL, 0, &ip_mtudisc, 0, 2313 CTL_NET, PF_INET, IPPROTO_IP, 2314 IPCTL_MTUDISC, CTL_EOL); 2315 sysctl_createv(clog, 0, NULL, NULL, 2316 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2317 CTLTYPE_INT, "anonportmin", 2318 SYSCTL_DESCR("Lowest ephemeral port number to assign"), 2319 sysctl_net_inet_ip_ports, 0, &anonportmin, 0, 2320 CTL_NET, PF_INET, IPPROTO_IP, 2321 IPCTL_ANONPORTMIN, CTL_EOL); 2322 sysctl_createv(clog, 0, NULL, NULL, 2323 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2324 CTLTYPE_INT, "anonportmax", 2325 SYSCTL_DESCR("Highest ephemeral port number to assign"), 2326 sysctl_net_inet_ip_ports, 0, &anonportmax, 0, 2327 CTL_NET, PF_INET, IPPROTO_IP, 2328 IPCTL_ANONPORTMAX, CTL_EOL); 2329 sysctl_createv(clog, 0, NULL, NULL, 2330 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2331 CTLTYPE_INT, "mtudisctimeout", 2332 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"), 2333 sysctl_net_inet_ip_pmtudto, 0, &ip_mtudisc_timeout, 0, 2334 CTL_NET, PF_INET, IPPROTO_IP, 2335 IPCTL_MTUDISCTIMEOUT, CTL_EOL); 2336 #ifdef GATEWAY 2337 sysctl_createv(clog, 0, NULL, NULL, 2338 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2339 CTLTYPE_INT, "maxflows", 2340 SYSCTL_DESCR("Number of flows for fast forwarding"), 2341 sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0, 2342 CTL_NET, PF_INET, IPPROTO_IP, 2343 IPCTL_MAXFLOWS, CTL_EOL); 2344 sysctl_createv(clog, 0, NULL, NULL, 2345 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2346 CTLTYPE_INT, "hashsize", 2347 SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"), 2348 sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0, 2349 CTL_NET, PF_INET, IPPROTO_IP, 2350 CTL_CREATE, CTL_EOL); 2351 #endif /* GATEWAY */ 2352 sysctl_createv(clog, 0, NULL, NULL, 2353 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2354 CTLTYPE_INT, "hostzerobroadcast", 2355 SYSCTL_DESCR("All zeroes address is broadcast address"), 2356 NULL, 0, &hostzeroisbroadcast, 0, 2357 CTL_NET, PF_INET, IPPROTO_IP, 2358 IPCTL_HOSTZEROBROADCAST, CTL_EOL); 2359 #if NGIF > 0 2360 sysctl_createv(clog, 0, NULL, NULL, 2361 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2362 CTLTYPE_INT, "gifttl", 2363 SYSCTL_DESCR("Default TTL for a gif tunnel datagram"), 2364 NULL, 0, &ip_gif_ttl, 0, 2365 CTL_NET, PF_INET, IPPROTO_IP, 2366 IPCTL_GIF_TTL, CTL_EOL); 2367 #endif /* NGIF */ 2368 #ifndef IPNOPRIVPORTS 2369 sysctl_createv(clog, 0, NULL, NULL, 2370 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2371 CTLTYPE_INT, "lowportmin", 2372 SYSCTL_DESCR("Lowest privileged ephemeral port number " 2373 "to assign"), 2374 sysctl_net_inet_ip_ports, 0, &lowportmin, 0, 2375 CTL_NET, PF_INET, IPPROTO_IP, 2376 IPCTL_LOWPORTMIN, CTL_EOL); 2377 sysctl_createv(clog, 0, NULL, NULL, 2378 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2379 CTLTYPE_INT, "lowportmax", 2380 SYSCTL_DESCR("Highest privileged ephemeral port number " 2381 "to assign"), 2382 sysctl_net_inet_ip_ports, 0, &lowportmax, 0, 2383 CTL_NET, PF_INET, IPPROTO_IP, 2384 IPCTL_LOWPORTMAX, CTL_EOL); 2385 #endif /* IPNOPRIVPORTS */ 2386 sysctl_createv(clog, 0, NULL, NULL, 2387 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2388 CTLTYPE_INT, "maxfragpackets", 2389 SYSCTL_DESCR("Maximum number of fragments to retain for " 2390 "possible reassembly"), 2391 NULL, 0, &ip_maxfragpackets, 0, 2392 CTL_NET, PF_INET, IPPROTO_IP, 2393 IPCTL_MAXFRAGPACKETS, CTL_EOL); 2394 #if NGRE > 0 2395 sysctl_createv(clog, 0, NULL, NULL, 2396 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2397 CTLTYPE_INT, "grettl", 2398 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"), 2399 NULL, 0, &ip_gre_ttl, 0, 2400 CTL_NET, PF_INET, IPPROTO_IP, 2401 IPCTL_GRE_TTL, CTL_EOL); 2402 #endif /* NGRE */ 2403 sysctl_createv(clog, 0, NULL, NULL, 2404 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2405 CTLTYPE_INT, "checkinterface", 2406 SYSCTL_DESCR("Enable receive side of Strong ES model " 2407 "from RFC1122"), 2408 NULL, 0, &ip_checkinterface, 0, 2409 CTL_NET, PF_INET, IPPROTO_IP, 2410 IPCTL_CHECKINTERFACE, CTL_EOL); 2411 sysctl_createv(clog, 0, NULL, NULL, 2412 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2413 CTLTYPE_INT, "random_id", 2414 SYSCTL_DESCR("Assign random ip_id values"), 2415 NULL, 0, &ip_do_randomid, 0, 2416 CTL_NET, PF_INET, IPPROTO_IP, 2417 IPCTL_RANDOMID, CTL_EOL); 2418 sysctl_createv(clog, 0, NULL, NULL, 2419 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2420 CTLTYPE_INT, "do_loopback_cksum", 2421 SYSCTL_DESCR("Perform IP checksum on loopback"), 2422 NULL, 0, &ip_do_loopback_cksum, 0, 2423 CTL_NET, PF_INET, IPPROTO_IP, 2424 IPCTL_LOOPBACKCKSUM, CTL_EOL); 2425 sysctl_createv(clog, 0, NULL, NULL, 2426 CTLFLAG_PERMANENT, 2427 CTLTYPE_STRUCT, "stats", 2428 SYSCTL_DESCR("IP statistics"), 2429 sysctl_net_inet_ip_stats, 0, NULL, 0, 2430 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS, 2431 CTL_EOL); 2432 } 2433 2434 void 2435 ip_statinc(u_int stat) 2436 { 2437 2438 KASSERT(stat < IP_NSTATS); 2439 IP_STATINC(stat); 2440 } 2441