ip_input.c revision 1.267
1 /* $NetBSD: ip_input.c,v 1.267 2008/04/23 06:09:04 thorpej Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * Copyright (c) 1982, 1986, 1988, 1993 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. Neither the name of the University nor the names of its contributors 82 * may be used to endorse or promote products derived from this software 83 * without specific prior written permission. 84 * 85 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 86 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 87 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 88 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 89 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 90 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 91 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 92 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 93 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 94 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 95 * SUCH DAMAGE. 96 * 97 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 98 */ 99 100 #include <sys/cdefs.h> 101 __KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.267 2008/04/23 06:09:04 thorpej Exp $"); 102 103 #include "opt_inet.h" 104 #include "opt_gateway.h" 105 #include "opt_pfil_hooks.h" 106 #include "opt_ipsec.h" 107 #include "opt_mrouting.h" 108 #include "opt_mbuftrace.h" 109 #include "opt_inet_csum.h" 110 111 #include <sys/param.h> 112 #include <sys/systm.h> 113 #include <sys/malloc.h> 114 #include <sys/mbuf.h> 115 #include <sys/domain.h> 116 #include <sys/protosw.h> 117 #include <sys/socket.h> 118 #include <sys/socketvar.h> 119 #include <sys/errno.h> 120 #include <sys/time.h> 121 #include <sys/kernel.h> 122 #include <sys/pool.h> 123 #include <sys/sysctl.h> 124 #include <sys/kauth.h> 125 126 #include <net/if.h> 127 #include <net/if_dl.h> 128 #include <net/route.h> 129 #include <net/pfil.h> 130 131 #include <netinet/in.h> 132 #include <netinet/in_systm.h> 133 #include <netinet/ip.h> 134 #include <netinet/in_pcb.h> 135 #include <netinet/in_proto.h> 136 #include <netinet/in_var.h> 137 #include <netinet/ip_var.h> 138 #include <netinet/ip_private.h> 139 #include <netinet/ip_icmp.h> 140 /* just for gif_ttl */ 141 #include <netinet/in_gif.h> 142 #include "gif.h" 143 #include <net/if_gre.h> 144 #include "gre.h" 145 146 #ifdef MROUTING 147 #include <netinet/ip_mroute.h> 148 #endif 149 150 #ifdef IPSEC 151 #include <netinet6/ipsec.h> 152 #include <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 */ 194 int ipforwarding = IPFORWARDING; 195 int ipsendredirects = IPSENDREDIRECTS; 196 int ip_defttl = IPDEFTTL; 197 int ip_forwsrcrt = IPFORWSRCRT; 198 int ip_directedbcast = IPDIRECTEDBCAST; 199 int ip_allowsrcrt = IPALLOWSRCRT; 200 int ip_mtudisc = IPMTUDISC; 201 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 202 #ifdef DIAGNOSTIC 203 int ipprintfs = 0; 204 #endif 205 206 int 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 */ 221 int ip_checkinterface = 0; 222 223 224 struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 225 226 int ipqmaxlen = IFQ_MAXLEN; 227 u_long in_ifaddrhash; /* size of hash table - 1 */ 228 int in_ifaddrentries; /* total number of addrs */ 229 struct in_ifaddrhead in_ifaddrhead; 230 struct in_ifaddrhashhead *in_ifaddrhashtbl; 231 u_long in_multihash; /* size of hash table - 1 */ 232 int in_multientries; /* total number of addrs */ 233 struct in_multihashhead *in_multihashtbl; 234 struct ifqueue ipintrq; 235 uint16_t ip_id; 236 237 percpu_t *ipstat_percpu; 238 239 #ifdef PFIL_HOOKS 240 struct 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 */ 247 static int ip_nmbclusters; /* copy of nmbclusters */ 248 static void ip_nmbclusters_changed(void); /* recalc limits */ 249 250 #define CHECK_NMBCLUSTER_PARAMS() \ 251 do { \ 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) 262 struct ipqhead ipq[IPREASS_NHASH]; 263 int ipq_locked; 264 static int ip_nfragpackets; /* packets in reass queue */ 265 static int ip_nfrags; /* total fragments in reass queues */ 266 267 int ip_maxfragpackets = 200; /* limit on packets. XXX sysctl */ 268 int 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 */ 282 static u_int ip_reass_ttl_decr(u_int ticks); 283 static void ip_reass_drophalf(void); 284 285 286 static inline int ipq_lock_try(void); 287 static inline void ipq_unlock(void); 288 289 static inline int 290 ipq_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 } 307 308 static inline void 309 ipq_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() \ 320 do { \ 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() \ 327 do { \ 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() 339 340 POOL_INIT(inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", NULL, 341 IPL_SOFTNET); 342 POOL_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> 347 348 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 349 NULL, "inet", "hwcsum bad"); 350 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 351 NULL, "inet", "hwcsum ok"); 352 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 353 NULL, "inet", "swcsum"); 354 355 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 356 357 EVCNT_ATTACH_STATIC(ip_hwcsum_bad); 358 EVCNT_ATTACH_STATIC(ip_hwcsum_ok); 359 EVCNT_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 */ 374 int ip_nhops = 0; 375 static 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; 381 382 static void save_rte(u_char *, struct in_addr); 383 384 #ifdef MBUFTRACE 385 struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx"); 386 struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx"); 387 #endif 388 389 /* 390 * Compute IP limits derived from the value of nmbclusters. 391 */ 392 static void 393 ip_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 */ 403 void 404 ip_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 } 456 457 struct sockaddr_in ipaddr = { 458 .sin_len = sizeof(ipaddr), 459 .sin_family = AF_INET, 460 }; 461 struct route ipforward_rt; 462 463 /* 464 * IP software interrupt routine 465 */ 466 void 467 ipintr(void) 468 { 469 int s; 470 struct mbuf *m; 471 472 while (!IF_IS_EMPTY(&ipintrq)) { 473 s = splnet(); 474 IF_DEQUEUE(&ipintrq, m); 475 splx(s); 476 if (m == 0) 477 return; 478 ip_input(m); 479 } 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 goto bad; 935 } 936 goto found; 937 } 938 } 939 fp = 0; 940 found: 941 942 /* 943 * Adjust ip_len to not reflect header, 944 * set ipqe_mff if more fragments are expected, 945 * convert offset of this to bytes. 946 */ 947 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 948 mff = (ip->ip_off & htons(IP_MF)) != 0; 949 if (mff) { 950 /* 951 * Make sure that fragments have a data length 952 * that's a non-zero multiple of 8 bytes. 953 */ 954 if (ntohs(ip->ip_len) == 0 || 955 (ntohs(ip->ip_len) & 0x7) != 0) { 956 IP_STATINC(IP_STAT_BADFRAGS); 957 IPQ_UNLOCK(); 958 goto bad; 959 } 960 } 961 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 962 963 /* 964 * If datagram marked as having more fragments 965 * or if this is not the first fragment, 966 * attempt reassembly; if it succeeds, proceed. 967 */ 968 if (mff || ip->ip_off != htons(0)) { 969 IP_STATINC(IP_STAT_FRAGMENTS); 970 s = splvm(); 971 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 972 splx(s); 973 if (ipqe == NULL) { 974 IP_STATINC(IP_STAT_RCVMEMDROP); 975 IPQ_UNLOCK(); 976 goto bad; 977 } 978 ipqe->ipqe_mff = mff; 979 ipqe->ipqe_m = m; 980 ipqe->ipqe_ip = ip; 981 m = ip_reass(ipqe, fp, &ipq[hash]); 982 if (m == 0) { 983 IPQ_UNLOCK(); 984 return; 985 } 986 IP_STATINC(IP_STAT_REASSEMBLED); 987 ip = mtod(m, struct ip *); 988 hlen = ip->ip_hl << 2; 989 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 990 } else 991 if (fp) 992 ip_freef(fp); 993 IPQ_UNLOCK(); 994 } 995 996 #if defined(IPSEC) 997 /* 998 * enforce IPsec policy checking if we are seeing last header. 999 * note that we do not visit this with protocols with pcb layer 1000 * code - like udp/tcp/raw ip. 1001 */ 1002 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 1003 ipsec4_in_reject(m, NULL)) { 1004 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1005 goto bad; 1006 } 1007 #endif 1008 #ifdef FAST_IPSEC 1009 /* 1010 * enforce IPsec policy checking if we are seeing last header. 1011 * note that we do not visit this with protocols with pcb layer 1012 * code - like udp/tcp/raw ip. 1013 */ 1014 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 1015 /* 1016 * Check if the packet has already had IPsec processing 1017 * done. If so, then just pass it along. This tag gets 1018 * set during AH, ESP, etc. input handling, before the 1019 * packet is returned to the ip input queue for delivery. 1020 */ 1021 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 1022 s = splsoftnet(); 1023 if (mtag != NULL) { 1024 tdbi = (struct tdb_ident *)(mtag + 1); 1025 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 1026 } else { 1027 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1028 IP_FORWARDING, &error); 1029 } 1030 if (sp != NULL) { 1031 /* 1032 * Check security policy against packet attributes. 1033 */ 1034 error = ipsec_in_reject(sp, m); 1035 KEY_FREESP(&sp); 1036 } else { 1037 /* XXX error stat??? */ 1038 error = EINVAL; 1039 DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 1040 } 1041 splx(s); 1042 if (error) 1043 goto bad; 1044 } 1045 #endif /* FAST_IPSEC */ 1046 1047 /* 1048 * Switch out to protocol's input routine. 1049 */ 1050 #if IFA_STATS 1051 if (ia && ip) 1052 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 1053 #endif 1054 IP_STATINC(IP_STAT_DELIVERED); 1055 { 1056 int off = hlen, nh = ip->ip_p; 1057 1058 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 1059 return; 1060 } 1061 bad: 1062 m_freem(m); 1063 return; 1064 1065 badcsum: 1066 IP_STATINC(IP_STAT_BADSUM); 1067 m_freem(m); 1068 } 1069 1070 /* 1071 * Take incoming datagram fragment and try to 1072 * reassemble it into whole datagram. If a chain for 1073 * reassembly of this datagram already exists, then it 1074 * is given as fp; otherwise have to make a chain. 1075 */ 1076 struct mbuf * 1077 ip_reass(struct ipqent *ipqe, struct ipq *fp, struct ipqhead *ipqhead) 1078 { 1079 struct mbuf *m = ipqe->ipqe_m; 1080 struct ipqent *nq, *p, *q; 1081 struct ip *ip; 1082 struct mbuf *t; 1083 int hlen = ipqe->ipqe_ip->ip_hl << 2; 1084 int i, next, s; 1085 1086 IPQ_LOCK_CHECK(); 1087 1088 /* 1089 * Presence of header sizes in mbufs 1090 * would confuse code below. 1091 */ 1092 m->m_data += hlen; 1093 m->m_len -= hlen; 1094 1095 #ifdef notyet 1096 /* make sure fragment limit is up-to-date */ 1097 CHECK_NMBCLUSTER_PARAMS(); 1098 1099 /* If we have too many fragments, drop the older half. */ 1100 if (ip_nfrags >= ip_maxfrags) 1101 ip_reass_drophalf(void); 1102 #endif 1103 1104 /* 1105 * We are about to add a fragment; increment frag count. 1106 */ 1107 ip_nfrags++; 1108 1109 /* 1110 * If first fragment to arrive, create a reassembly queue. 1111 */ 1112 if (fp == 0) { 1113 /* 1114 * Enforce upper bound on number of fragmented packets 1115 * for which we attempt reassembly; 1116 * If maxfrag is 0, never accept fragments. 1117 * If maxfrag is -1, accept all fragments without limitation. 1118 */ 1119 if (ip_maxfragpackets < 0) 1120 ; 1121 else if (ip_nfragpackets >= ip_maxfragpackets) 1122 goto dropfrag; 1123 ip_nfragpackets++; 1124 MALLOC(fp, struct ipq *, sizeof (struct ipq), 1125 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 int s = splsoftnet(); 1393 1394 IPQ_LOCK(); 1395 1396 /* Age TTL of all fragments by 1 tick .*/ 1397 median_ttl = ip_reass_ttl_decr(1); 1398 1399 /* make sure fragment limit is up-to-date */ 1400 CHECK_NMBCLUSTER_PARAMS(); 1401 1402 /* If we have too many fragments, drop the older half. */ 1403 if (ip_nfrags > ip_maxfrags) 1404 ip_reass_ttl_decr(median_ttl); 1405 1406 /* 1407 * If we are over the maximum number of fragmented packets 1408 * (due to the limit being lowered), drain off 1409 * enough to get down to the new limit. Start draining 1410 * from the reassembly hashqueue most recently drained. 1411 */ 1412 if (ip_maxfragpackets < 0) 1413 ; 1414 else { 1415 int wrapped = 0; 1416 1417 i = dropscanidx; 1418 while (ip_nfragpackets > ip_maxfragpackets && wrapped == 0) { 1419 while (LIST_FIRST(&ipq[i]) != NULL) 1420 ip_freef(LIST_FIRST(&ipq[i])); 1421 if (++i >= IPREASS_NHASH) { 1422 i = 0; 1423 } 1424 /* 1425 * Dont scan forever even if fragment counters are 1426 * wrong: stop after scanning entire reassembly queue. 1427 */ 1428 if (i == dropscanidx) 1429 wrapped = 1; 1430 } 1431 dropscanidx = i; 1432 } 1433 IPQ_UNLOCK(); 1434 splx(s); 1435 } 1436 1437 /* 1438 * Drain off all datagram fragments. 1439 */ 1440 void 1441 ip_drain(void) 1442 { 1443 1444 /* 1445 * We may be called from a device's interrupt context. If 1446 * the ipq is already busy, just bail out now. 1447 */ 1448 if (ipq_lock_try() == 0) 1449 return; 1450 1451 /* 1452 * Drop half the total fragments now. If more mbufs are needed, 1453 * we will be called again soon. 1454 */ 1455 ip_reass_drophalf(); 1456 1457 IPQ_UNLOCK(); 1458 } 1459 1460 /* 1461 * Do option processing on a datagram, 1462 * possibly discarding it if bad options are encountered, 1463 * or forwarding it if source-routed. 1464 * Returns 1 if packet has been forwarded/freed, 1465 * 0 if the packet should be processed further. 1466 */ 1467 int 1468 ip_dooptions(struct mbuf *m) 1469 { 1470 struct ip *ip = mtod(m, struct ip *); 1471 u_char *cp, *cp0; 1472 struct ip_timestamp *ipt; 1473 struct in_ifaddr *ia; 1474 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1475 struct in_addr dst; 1476 n_time ntime; 1477 1478 dst = ip->ip_dst; 1479 cp = (u_char *)(ip + 1); 1480 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1481 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1482 opt = cp[IPOPT_OPTVAL]; 1483 if (opt == IPOPT_EOL) 1484 break; 1485 if (opt == IPOPT_NOP) 1486 optlen = 1; 1487 else { 1488 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1489 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1490 goto bad; 1491 } 1492 optlen = cp[IPOPT_OLEN]; 1493 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1494 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1495 goto bad; 1496 } 1497 } 1498 switch (opt) { 1499 1500 default: 1501 break; 1502 1503 /* 1504 * Source routing with record. 1505 * Find interface with current destination address. 1506 * If none on this machine then drop if strictly routed, 1507 * or do nothing if loosely routed. 1508 * Record interface address and bring up next address 1509 * component. If strictly routed make sure next 1510 * address is on directly accessible net. 1511 */ 1512 case IPOPT_LSRR: 1513 case IPOPT_SSRR: 1514 if (ip_allowsrcrt == 0) { 1515 type = ICMP_UNREACH; 1516 code = ICMP_UNREACH_NET_PROHIB; 1517 goto bad; 1518 } 1519 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1520 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1521 goto bad; 1522 } 1523 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1524 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1525 goto bad; 1526 } 1527 ipaddr.sin_addr = ip->ip_dst; 1528 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1529 if (ia == 0) { 1530 if (opt == IPOPT_SSRR) { 1531 type = ICMP_UNREACH; 1532 code = ICMP_UNREACH_SRCFAIL; 1533 goto bad; 1534 } 1535 /* 1536 * Loose routing, and not at next destination 1537 * yet; nothing to do except forward. 1538 */ 1539 break; 1540 } 1541 off--; /* 0 origin */ 1542 if ((off + sizeof(struct in_addr)) > optlen) { 1543 /* 1544 * End of source route. Should be for us. 1545 */ 1546 save_rte(cp, ip->ip_src); 1547 break; 1548 } 1549 /* 1550 * locate outgoing interface 1551 */ 1552 bcopy((void *)(cp + off), (void *)&ipaddr.sin_addr, 1553 sizeof(ipaddr.sin_addr)); 1554 if (opt == IPOPT_SSRR) 1555 ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr))); 1556 else 1557 ia = ip_rtaddr(ipaddr.sin_addr); 1558 if (ia == 0) { 1559 type = ICMP_UNREACH; 1560 code = ICMP_UNREACH_SRCFAIL; 1561 goto bad; 1562 } 1563 ip->ip_dst = ipaddr.sin_addr; 1564 bcopy((void *)&ia->ia_addr.sin_addr, 1565 (void *)(cp + off), sizeof(struct in_addr)); 1566 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1567 /* 1568 * Let ip_intr's mcast routing check handle mcast pkts 1569 */ 1570 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1571 break; 1572 1573 case IPOPT_RR: 1574 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1575 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1576 goto bad; 1577 } 1578 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1579 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1580 goto bad; 1581 } 1582 /* 1583 * If no space remains, ignore. 1584 */ 1585 off--; /* 0 origin */ 1586 if ((off + sizeof(struct in_addr)) > optlen) 1587 break; 1588 bcopy((void *)(&ip->ip_dst), (void *)&ipaddr.sin_addr, 1589 sizeof(ipaddr.sin_addr)); 1590 /* 1591 * locate outgoing interface; if we're the destination, 1592 * use the incoming interface (should be same). 1593 */ 1594 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1595 == NULL && 1596 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1597 type = ICMP_UNREACH; 1598 code = ICMP_UNREACH_HOST; 1599 goto bad; 1600 } 1601 bcopy((void *)&ia->ia_addr.sin_addr, 1602 (void *)(cp + off), sizeof(struct in_addr)); 1603 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1604 break; 1605 1606 case IPOPT_TS: 1607 code = cp - (u_char *)ip; 1608 ipt = (struct ip_timestamp *)cp; 1609 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1610 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1611 goto bad; 1612 } 1613 if (ipt->ipt_ptr < 5) { 1614 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1615 goto bad; 1616 } 1617 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1618 if (++ipt->ipt_oflw == 0) { 1619 code = (u_char *)&ipt->ipt_ptr - 1620 (u_char *)ip; 1621 goto bad; 1622 } 1623 break; 1624 } 1625 cp0 = (cp + ipt->ipt_ptr - 1); 1626 switch (ipt->ipt_flg) { 1627 1628 case IPOPT_TS_TSONLY: 1629 break; 1630 1631 case IPOPT_TS_TSANDADDR: 1632 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1633 sizeof(struct in_addr) > ipt->ipt_len) { 1634 code = (u_char *)&ipt->ipt_ptr - 1635 (u_char *)ip; 1636 goto bad; 1637 } 1638 ipaddr.sin_addr = dst; 1639 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1640 m->m_pkthdr.rcvif)); 1641 if (ia == 0) 1642 continue; 1643 bcopy(&ia->ia_addr.sin_addr, 1644 cp0, sizeof(struct in_addr)); 1645 ipt->ipt_ptr += sizeof(struct in_addr); 1646 break; 1647 1648 case IPOPT_TS_PRESPEC: 1649 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1650 sizeof(struct in_addr) > ipt->ipt_len) { 1651 code = (u_char *)&ipt->ipt_ptr - 1652 (u_char *)ip; 1653 goto bad; 1654 } 1655 bcopy(cp0, &ipaddr.sin_addr, 1656 sizeof(struct in_addr)); 1657 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1658 == NULL) 1659 continue; 1660 ipt->ipt_ptr += sizeof(struct in_addr); 1661 break; 1662 1663 default: 1664 /* XXX can't take &ipt->ipt_flg */ 1665 code = (u_char *)&ipt->ipt_ptr - 1666 (u_char *)ip + 1; 1667 goto bad; 1668 } 1669 ntime = iptime(); 1670 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1671 memmove((char *)cp + ipt->ipt_ptr - 1, cp0, 1672 sizeof(n_time)); 1673 ipt->ipt_ptr += sizeof(n_time); 1674 } 1675 } 1676 if (forward) { 1677 if (ip_forwsrcrt == 0) { 1678 type = ICMP_UNREACH; 1679 code = ICMP_UNREACH_SRCFAIL; 1680 goto bad; 1681 } 1682 ip_forward(m, 1); 1683 return (1); 1684 } 1685 return (0); 1686 bad: 1687 icmp_error(m, type, code, 0, 0); 1688 IP_STATINC(IP_STAT_BADOPTIONS); 1689 return (1); 1690 } 1691 1692 /* 1693 * Given address of next destination (final or next hop), 1694 * return internet address info of interface to be used to get there. 1695 */ 1696 struct in_ifaddr * 1697 ip_rtaddr(struct in_addr dst) 1698 { 1699 struct rtentry *rt; 1700 union { 1701 struct sockaddr dst; 1702 struct sockaddr_in dst4; 1703 } u; 1704 1705 sockaddr_in_init(&u.dst4, &dst, 0); 1706 1707 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) 1708 return NULL; 1709 1710 return ifatoia(rt->rt_ifa); 1711 } 1712 1713 /* 1714 * Save incoming source route for use in replies, 1715 * to be picked up later by ip_srcroute if the receiver is interested. 1716 */ 1717 void 1718 save_rte(u_char *option, struct in_addr dst) 1719 { 1720 unsigned olen; 1721 1722 olen = option[IPOPT_OLEN]; 1723 #ifdef DIAGNOSTIC 1724 if (ipprintfs) 1725 printf("save_rte: olen %d\n", olen); 1726 #endif /* 0 */ 1727 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1728 return; 1729 bcopy((void *)option, (void *)ip_srcrt.srcopt, olen); 1730 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1731 ip_srcrt.dst = dst; 1732 } 1733 1734 /* 1735 * Retrieve incoming source route for use in replies, 1736 * in the same form used by setsockopt. 1737 * The first hop is placed before the options, will be removed later. 1738 */ 1739 struct mbuf * 1740 ip_srcroute(void) 1741 { 1742 struct in_addr *p, *q; 1743 struct mbuf *m; 1744 1745 if (ip_nhops == 0) 1746 return NULL; 1747 m = m_get(M_DONTWAIT, MT_SOOPTS); 1748 if (m == 0) 1749 return NULL; 1750 1751 MCLAIM(m, &inetdomain.dom_mowner); 1752 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1753 1754 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1755 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1756 OPTSIZ; 1757 #ifdef DIAGNOSTIC 1758 if (ipprintfs) 1759 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1760 #endif 1761 1762 /* 1763 * First save first hop for return route 1764 */ 1765 p = &ip_srcrt.route[ip_nhops - 1]; 1766 *(mtod(m, struct in_addr *)) = *p--; 1767 #ifdef DIAGNOSTIC 1768 if (ipprintfs) 1769 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1770 #endif 1771 1772 /* 1773 * Copy option fields and padding (nop) to mbuf. 1774 */ 1775 ip_srcrt.nop = IPOPT_NOP; 1776 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1777 memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop, 1778 OPTSIZ); 1779 q = (struct in_addr *)(mtod(m, char *) + 1780 sizeof(struct in_addr) + OPTSIZ); 1781 #undef OPTSIZ 1782 /* 1783 * Record return path as an IP source route, 1784 * reversing the path (pointers are now aligned). 1785 */ 1786 while (p >= ip_srcrt.route) { 1787 #ifdef DIAGNOSTIC 1788 if (ipprintfs) 1789 printf(" %x", ntohl(q->s_addr)); 1790 #endif 1791 *q++ = *p--; 1792 } 1793 /* 1794 * Last hop goes to final destination. 1795 */ 1796 *q = ip_srcrt.dst; 1797 #ifdef DIAGNOSTIC 1798 if (ipprintfs) 1799 printf(" %x\n", ntohl(q->s_addr)); 1800 #endif 1801 return (m); 1802 } 1803 1804 const int inetctlerrmap[PRC_NCMDS] = { 1805 [PRC_MSGSIZE] = EMSGSIZE, 1806 [PRC_HOSTDEAD] = EHOSTDOWN, 1807 [PRC_HOSTUNREACH] = EHOSTUNREACH, 1808 [PRC_UNREACH_NET] = EHOSTUNREACH, 1809 [PRC_UNREACH_HOST] = EHOSTUNREACH, 1810 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED, 1811 [PRC_UNREACH_PORT] = ECONNREFUSED, 1812 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH, 1813 [PRC_PARAMPROB] = ENOPROTOOPT, 1814 }; 1815 1816 /* 1817 * Forward a packet. If some error occurs return the sender 1818 * an icmp packet. Note we can't always generate a meaningful 1819 * icmp message because icmp doesn't have a large enough repertoire 1820 * of codes and types. 1821 * 1822 * If not forwarding, just drop the packet. This could be confusing 1823 * if ipforwarding was zero but some routing protocol was advancing 1824 * us as a gateway to somewhere. However, we must let the routing 1825 * protocol deal with that. 1826 * 1827 * The srcrt parameter indicates whether the packet is being forwarded 1828 * via a source route. 1829 */ 1830 void 1831 ip_forward(struct mbuf *m, int srcrt) 1832 { 1833 struct ip *ip = mtod(m, struct ip *); 1834 struct rtentry *rt; 1835 int error, type = 0, code = 0, destmtu = 0; 1836 struct mbuf *mcopy; 1837 n_long dest; 1838 union { 1839 struct sockaddr dst; 1840 struct sockaddr_in dst4; 1841 } u; 1842 1843 /* 1844 * We are now in the output path. 1845 */ 1846 MCLAIM(m, &ip_tx_mowner); 1847 1848 /* 1849 * Clear any in-bound checksum flags for this packet. 1850 */ 1851 m->m_pkthdr.csum_flags = 0; 1852 1853 dest = 0; 1854 #ifdef DIAGNOSTIC 1855 if (ipprintfs) { 1856 printf("forward: src %s ", inet_ntoa(ip->ip_src)); 1857 printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl); 1858 } 1859 #endif 1860 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1861 IP_STATINC(IP_STAT_CANTFORWARD); 1862 m_freem(m); 1863 return; 1864 } 1865 if (ip->ip_ttl <= IPTTLDEC) { 1866 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1867 return; 1868 } 1869 1870 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0); 1871 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) { 1872 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0); 1873 return; 1874 } 1875 1876 /* 1877 * Save at most 68 bytes of the packet in case 1878 * we need to generate an ICMP message to the src. 1879 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1880 */ 1881 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1882 if (mcopy) 1883 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1884 1885 ip->ip_ttl -= IPTTLDEC; 1886 1887 /* 1888 * If forwarding packet using same interface that it came in on, 1889 * perhaps should send a redirect to sender to shortcut a hop. 1890 * Only send redirect if source is sending directly to us, 1891 * and if packet was not source routed (or has any options). 1892 * Also, don't send redirect if forwarding using a default route 1893 * or a route modified by a redirect. 1894 */ 1895 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1896 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1897 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) && 1898 ipsendredirects && !srcrt) { 1899 if (rt->rt_ifa && 1900 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1901 ifatoia(rt->rt_ifa)->ia_subnet) { 1902 if (rt->rt_flags & RTF_GATEWAY) 1903 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1904 else 1905 dest = ip->ip_dst.s_addr; 1906 /* 1907 * Router requirements says to only send host 1908 * redirects. 1909 */ 1910 type = ICMP_REDIRECT; 1911 code = ICMP_REDIRECT_HOST; 1912 #ifdef DIAGNOSTIC 1913 if (ipprintfs) 1914 printf("redirect (%d) to %x\n", code, 1915 (u_int32_t)dest); 1916 #endif 1917 } 1918 } 1919 1920 error = ip_output(m, NULL, &ipforward_rt, 1921 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1922 (struct ip_moptions *)NULL, (struct socket *)NULL); 1923 1924 if (error) 1925 IP_STATINC(IP_STAT_CANTFORWARD); 1926 else { 1927 uint64_t *ips = IP_STAT_GETREF(); 1928 ips[IP_STAT_FORWARD]++; 1929 if (type) { 1930 ips[IP_STAT_REDIRECTSENT]++; 1931 IP_STAT_PUTREF(); 1932 } else { 1933 IP_STAT_PUTREF(); 1934 if (mcopy) { 1935 #ifdef GATEWAY 1936 if (mcopy->m_flags & M_CANFASTFWD) 1937 ipflow_create(&ipforward_rt, mcopy); 1938 #endif 1939 m_freem(mcopy); 1940 } 1941 return; 1942 } 1943 } 1944 if (mcopy == NULL) 1945 return; 1946 1947 switch (error) { 1948 1949 case 0: /* forwarded, but need redirect */ 1950 /* type, code set above */ 1951 break; 1952 1953 case ENETUNREACH: /* shouldn't happen, checked above */ 1954 case EHOSTUNREACH: 1955 case ENETDOWN: 1956 case EHOSTDOWN: 1957 default: 1958 type = ICMP_UNREACH; 1959 code = ICMP_UNREACH_HOST; 1960 break; 1961 1962 case EMSGSIZE: 1963 type = ICMP_UNREACH; 1964 code = ICMP_UNREACH_NEEDFRAG; 1965 1966 if ((rt = rtcache_validate(&ipforward_rt)) != NULL) { 1967 1968 #if defined(IPSEC) || defined(FAST_IPSEC) 1969 /* 1970 * If the packet is routed over IPsec tunnel, tell the 1971 * originator the tunnel MTU. 1972 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1973 * XXX quickhack!!! 1974 */ 1975 1976 struct secpolicy *sp; 1977 int ipsecerror; 1978 size_t ipsechdr; 1979 struct route *ro; 1980 1981 sp = ipsec4_getpolicybyaddr(mcopy, 1982 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1983 &ipsecerror); 1984 #endif 1985 1986 destmtu = rt->rt_ifp->if_mtu; 1987 #if defined(IPSEC) || defined(FAST_IPSEC) 1988 if (sp != NULL) { 1989 /* count IPsec header size */ 1990 ipsechdr = ipsec4_hdrsiz(mcopy, 1991 IPSEC_DIR_OUTBOUND, NULL); 1992 1993 /* 1994 * find the correct route for outer IPv4 1995 * header, compute tunnel MTU. 1996 */ 1997 1998 if (sp->req != NULL 1999 && sp->req->sav != NULL 2000 && sp->req->sav->sah != NULL) { 2001 ro = &sp->req->sav->sah->sa_route; 2002 if (rt && rt->rt_ifp) { 2003 destmtu = 2004 rt->rt_rmx.rmx_mtu ? 2005 rt->rt_rmx.rmx_mtu : 2006 rt->rt_ifp->if_mtu; 2007 destmtu -= ipsechdr; 2008 } 2009 } 2010 2011 #ifdef IPSEC 2012 key_freesp(sp); 2013 #else 2014 KEY_FREESP(&sp); 2015 #endif 2016 } 2017 #endif /*defined(IPSEC) || defined(FAST_IPSEC)*/ 2018 } 2019 IP_STATINC(IP_STAT_CANTFRAG); 2020 break; 2021 2022 case ENOBUFS: 2023 #if 1 2024 /* 2025 * a router should not generate ICMP_SOURCEQUENCH as 2026 * required in RFC1812 Requirements for IP Version 4 Routers. 2027 * source quench could be a big problem under DoS attacks, 2028 * or if the underlying interface is rate-limited. 2029 */ 2030 if (mcopy) 2031 m_freem(mcopy); 2032 return; 2033 #else 2034 type = ICMP_SOURCEQUENCH; 2035 code = 0; 2036 break; 2037 #endif 2038 } 2039 icmp_error(mcopy, type, code, dest, destmtu); 2040 } 2041 2042 void 2043 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 2044 struct mbuf *m) 2045 { 2046 2047 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 2048 struct timeval tv; 2049 2050 microtime(&tv); 2051 *mp = sbcreatecontrol((void *) &tv, sizeof(tv), 2052 SCM_TIMESTAMP, SOL_SOCKET); 2053 if (*mp) 2054 mp = &(*mp)->m_next; 2055 } 2056 if (inp->inp_flags & INP_RECVDSTADDR) { 2057 *mp = sbcreatecontrol((void *) &ip->ip_dst, 2058 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 2059 if (*mp) 2060 mp = &(*mp)->m_next; 2061 } 2062 #ifdef notyet 2063 /* 2064 * XXX 2065 * Moving these out of udp_input() made them even more broken 2066 * than they already were. 2067 * - fenner (at) parc.xerox.com 2068 */ 2069 /* options were tossed already */ 2070 if (inp->inp_flags & INP_RECVOPTS) { 2071 *mp = sbcreatecontrol((void *) opts_deleted_above, 2072 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 2073 if (*mp) 2074 mp = &(*mp)->m_next; 2075 } 2076 /* ip_srcroute doesn't do what we want here, need to fix */ 2077 if (inp->inp_flags & INP_RECVRETOPTS) { 2078 *mp = sbcreatecontrol((void *) ip_srcroute(), 2079 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 2080 if (*mp) 2081 mp = &(*mp)->m_next; 2082 } 2083 #endif 2084 if (inp->inp_flags & INP_RECVIF) { 2085 struct sockaddr_dl sdl; 2086 2087 sockaddr_dl_init(&sdl, sizeof(sdl), 2088 (m->m_pkthdr.rcvif != NULL) 2089 ? m->m_pkthdr.rcvif->if_index 2090 : 0, 2091 0, NULL, 0, NULL, 0); 2092 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP); 2093 if (*mp) 2094 mp = &(*mp)->m_next; 2095 } 2096 } 2097 2098 /* 2099 * sysctl helper routine for net.inet.ip.forwsrcrt. 2100 */ 2101 static int 2102 sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS) 2103 { 2104 int error, tmp; 2105 struct sysctlnode node; 2106 2107 node = *rnode; 2108 tmp = ip_forwsrcrt; 2109 node.sysctl_data = &tmp; 2110 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2111 if (error || newp == NULL) 2112 return (error); 2113 2114 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT, 2115 0, NULL, NULL, NULL)) 2116 return (EPERM); 2117 2118 ip_forwsrcrt = tmp; 2119 2120 return (0); 2121 } 2122 2123 /* 2124 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the 2125 * range of the new value and tweaks timers if it changes. 2126 */ 2127 static int 2128 sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS) 2129 { 2130 int error, tmp; 2131 struct sysctlnode node; 2132 2133 node = *rnode; 2134 tmp = ip_mtudisc_timeout; 2135 node.sysctl_data = &tmp; 2136 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2137 if (error || newp == NULL) 2138 return (error); 2139 if (tmp < 0) 2140 return (EINVAL); 2141 2142 ip_mtudisc_timeout = tmp; 2143 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 2144 2145 return (0); 2146 } 2147 2148 #ifdef GATEWAY 2149 /* 2150 * sysctl helper routine for net.inet.ip.maxflows. 2151 */ 2152 static int 2153 sysctl_net_inet_ip_maxflows(SYSCTLFN_ARGS) 2154 { 2155 int s; 2156 2157 s = sysctl_lookup(SYSCTLFN_CALL(rnode)); 2158 if (s || newp == NULL) 2159 return (s); 2160 2161 s = splsoftnet(); 2162 ipflow_prune(); 2163 splx(s); 2164 2165 return (0); 2166 } 2167 2168 static int 2169 sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS) 2170 { 2171 int error, tmp; 2172 struct sysctlnode node; 2173 2174 node = *rnode; 2175 tmp = ip_hashsize; 2176 node.sysctl_data = &tmp; 2177 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2178 if (error || newp == NULL) 2179 return (error); 2180 2181 if ((tmp & (tmp - 1)) == 0 && tmp != 0) { 2182 /* 2183 * Can only fail due to malloc() 2184 */ 2185 if (ipflow_invalidate_all(tmp)) 2186 return ENOMEM; 2187 } else { 2188 /* 2189 * EINVAL if not a power of 2 2190 */ 2191 return EINVAL; 2192 } 2193 2194 return (0); 2195 } 2196 #endif /* GATEWAY */ 2197 2198 static int 2199 sysctl_net_inet_ip_stats(SYSCTLFN_ARGS) 2200 { 2201 netstat_sysctl_context ctx; 2202 uint64_t ips[IP_NSTATS]; 2203 2204 ctx.ctx_stat = ipstat_percpu; 2205 ctx.ctx_counters = ips; 2206 ctx.ctx_ncounters = IP_NSTATS; 2207 return (NETSTAT_SYSCTL(&ctx)); 2208 } 2209 2210 SYSCTL_SETUP(sysctl_net_inet_ip_setup, "sysctl net.inet.ip subtree setup") 2211 { 2212 extern int subnetsarelocal, hostzeroisbroadcast; 2213 2214 sysctl_createv(clog, 0, NULL, NULL, 2215 CTLFLAG_PERMANENT, 2216 CTLTYPE_NODE, "net", NULL, 2217 NULL, 0, NULL, 0, 2218 CTL_NET, CTL_EOL); 2219 sysctl_createv(clog, 0, NULL, NULL, 2220 CTLFLAG_PERMANENT, 2221 CTLTYPE_NODE, "inet", 2222 SYSCTL_DESCR("PF_INET related settings"), 2223 NULL, 0, NULL, 0, 2224 CTL_NET, PF_INET, CTL_EOL); 2225 sysctl_createv(clog, 0, NULL, NULL, 2226 CTLFLAG_PERMANENT, 2227 CTLTYPE_NODE, "ip", 2228 SYSCTL_DESCR("IPv4 related settings"), 2229 NULL, 0, NULL, 0, 2230 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL); 2231 2232 sysctl_createv(clog, 0, NULL, NULL, 2233 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2234 CTLTYPE_INT, "forwarding", 2235 SYSCTL_DESCR("Enable forwarding of INET datagrams"), 2236 NULL, 0, &ipforwarding, 0, 2237 CTL_NET, PF_INET, IPPROTO_IP, 2238 IPCTL_FORWARDING, CTL_EOL); 2239 sysctl_createv(clog, 0, NULL, NULL, 2240 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2241 CTLTYPE_INT, "redirect", 2242 SYSCTL_DESCR("Enable sending of ICMP redirect messages"), 2243 NULL, 0, &ipsendredirects, 0, 2244 CTL_NET, PF_INET, IPPROTO_IP, 2245 IPCTL_SENDREDIRECTS, CTL_EOL); 2246 sysctl_createv(clog, 0, NULL, NULL, 2247 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2248 CTLTYPE_INT, "ttl", 2249 SYSCTL_DESCR("Default TTL for an INET datagram"), 2250 NULL, 0, &ip_defttl, 0, 2251 CTL_NET, PF_INET, IPPROTO_IP, 2252 IPCTL_DEFTTL, CTL_EOL); 2253 #ifdef IPCTL_DEFMTU 2254 sysctl_createv(clog, 0, NULL, NULL, 2255 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */, 2256 CTLTYPE_INT, "mtu", 2257 SYSCTL_DESCR("Default MTA for an INET route"), 2258 NULL, 0, &ip_mtu, 0, 2259 CTL_NET, PF_INET, IPPROTO_IP, 2260 IPCTL_DEFMTU, CTL_EOL); 2261 #endif /* IPCTL_DEFMTU */ 2262 sysctl_createv(clog, 0, NULL, NULL, 2263 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2264 CTLTYPE_INT, "forwsrcrt", 2265 SYSCTL_DESCR("Enable forwarding of source-routed " 2266 "datagrams"), 2267 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0, 2268 CTL_NET, PF_INET, IPPROTO_IP, 2269 IPCTL_FORWSRCRT, CTL_EOL); 2270 sysctl_createv(clog, 0, NULL, NULL, 2271 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2272 CTLTYPE_INT, "directed-broadcast", 2273 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"), 2274 NULL, 0, &ip_directedbcast, 0, 2275 CTL_NET, PF_INET, IPPROTO_IP, 2276 IPCTL_DIRECTEDBCAST, CTL_EOL); 2277 sysctl_createv(clog, 0, NULL, NULL, 2278 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2279 CTLTYPE_INT, "allowsrcrt", 2280 SYSCTL_DESCR("Accept source-routed datagrams"), 2281 NULL, 0, &ip_allowsrcrt, 0, 2282 CTL_NET, PF_INET, IPPROTO_IP, 2283 IPCTL_ALLOWSRCRT, CTL_EOL); 2284 sysctl_createv(clog, 0, NULL, NULL, 2285 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2286 CTLTYPE_INT, "subnetsarelocal", 2287 SYSCTL_DESCR("Whether logical subnets are considered " 2288 "local"), 2289 NULL, 0, &subnetsarelocal, 0, 2290 CTL_NET, PF_INET, IPPROTO_IP, 2291 IPCTL_SUBNETSARELOCAL, CTL_EOL); 2292 sysctl_createv(clog, 0, NULL, NULL, 2293 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2294 CTLTYPE_INT, "mtudisc", 2295 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"), 2296 NULL, 0, &ip_mtudisc, 0, 2297 CTL_NET, PF_INET, IPPROTO_IP, 2298 IPCTL_MTUDISC, CTL_EOL); 2299 sysctl_createv(clog, 0, NULL, NULL, 2300 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2301 CTLTYPE_INT, "anonportmin", 2302 SYSCTL_DESCR("Lowest ephemeral port number to assign"), 2303 sysctl_net_inet_ip_ports, 0, &anonportmin, 0, 2304 CTL_NET, PF_INET, IPPROTO_IP, 2305 IPCTL_ANONPORTMIN, CTL_EOL); 2306 sysctl_createv(clog, 0, NULL, NULL, 2307 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2308 CTLTYPE_INT, "anonportmax", 2309 SYSCTL_DESCR("Highest ephemeral port number to assign"), 2310 sysctl_net_inet_ip_ports, 0, &anonportmax, 0, 2311 CTL_NET, PF_INET, IPPROTO_IP, 2312 IPCTL_ANONPORTMAX, CTL_EOL); 2313 sysctl_createv(clog, 0, NULL, NULL, 2314 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2315 CTLTYPE_INT, "mtudisctimeout", 2316 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"), 2317 sysctl_net_inet_ip_pmtudto, 0, &ip_mtudisc_timeout, 0, 2318 CTL_NET, PF_INET, IPPROTO_IP, 2319 IPCTL_MTUDISCTIMEOUT, CTL_EOL); 2320 #ifdef GATEWAY 2321 sysctl_createv(clog, 0, NULL, NULL, 2322 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2323 CTLTYPE_INT, "maxflows", 2324 SYSCTL_DESCR("Number of flows for fast forwarding"), 2325 sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0, 2326 CTL_NET, PF_INET, IPPROTO_IP, 2327 IPCTL_MAXFLOWS, CTL_EOL); 2328 sysctl_createv(clog, 0, NULL, NULL, 2329 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2330 CTLTYPE_INT, "hashsize", 2331 SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"), 2332 sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0, 2333 CTL_NET, PF_INET, IPPROTO_IP, 2334 CTL_CREATE, CTL_EOL); 2335 #endif /* GATEWAY */ 2336 sysctl_createv(clog, 0, NULL, NULL, 2337 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2338 CTLTYPE_INT, "hostzerobroadcast", 2339 SYSCTL_DESCR("All zeroes address is broadcast address"), 2340 NULL, 0, &hostzeroisbroadcast, 0, 2341 CTL_NET, PF_INET, IPPROTO_IP, 2342 IPCTL_HOSTZEROBROADCAST, CTL_EOL); 2343 #if NGIF > 0 2344 sysctl_createv(clog, 0, NULL, NULL, 2345 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2346 CTLTYPE_INT, "gifttl", 2347 SYSCTL_DESCR("Default TTL for a gif tunnel datagram"), 2348 NULL, 0, &ip_gif_ttl, 0, 2349 CTL_NET, PF_INET, IPPROTO_IP, 2350 IPCTL_GIF_TTL, CTL_EOL); 2351 #endif /* NGIF */ 2352 #ifndef IPNOPRIVPORTS 2353 sysctl_createv(clog, 0, NULL, NULL, 2354 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2355 CTLTYPE_INT, "lowportmin", 2356 SYSCTL_DESCR("Lowest privileged ephemeral port number " 2357 "to assign"), 2358 sysctl_net_inet_ip_ports, 0, &lowportmin, 0, 2359 CTL_NET, PF_INET, IPPROTO_IP, 2360 IPCTL_LOWPORTMIN, CTL_EOL); 2361 sysctl_createv(clog, 0, NULL, NULL, 2362 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2363 CTLTYPE_INT, "lowportmax", 2364 SYSCTL_DESCR("Highest privileged ephemeral port number " 2365 "to assign"), 2366 sysctl_net_inet_ip_ports, 0, &lowportmax, 0, 2367 CTL_NET, PF_INET, IPPROTO_IP, 2368 IPCTL_LOWPORTMAX, CTL_EOL); 2369 #endif /* IPNOPRIVPORTS */ 2370 sysctl_createv(clog, 0, NULL, NULL, 2371 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2372 CTLTYPE_INT, "maxfragpackets", 2373 SYSCTL_DESCR("Maximum number of fragments to retain for " 2374 "possible reassembly"), 2375 NULL, 0, &ip_maxfragpackets, 0, 2376 CTL_NET, PF_INET, IPPROTO_IP, 2377 IPCTL_MAXFRAGPACKETS, CTL_EOL); 2378 #if NGRE > 0 2379 sysctl_createv(clog, 0, NULL, NULL, 2380 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2381 CTLTYPE_INT, "grettl", 2382 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"), 2383 NULL, 0, &ip_gre_ttl, 0, 2384 CTL_NET, PF_INET, IPPROTO_IP, 2385 IPCTL_GRE_TTL, CTL_EOL); 2386 #endif /* NGRE */ 2387 sysctl_createv(clog, 0, NULL, NULL, 2388 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2389 CTLTYPE_INT, "checkinterface", 2390 SYSCTL_DESCR("Enable receive side of Strong ES model " 2391 "from RFC1122"), 2392 NULL, 0, &ip_checkinterface, 0, 2393 CTL_NET, PF_INET, IPPROTO_IP, 2394 IPCTL_CHECKINTERFACE, CTL_EOL); 2395 sysctl_createv(clog, 0, NULL, NULL, 2396 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2397 CTLTYPE_INT, "random_id", 2398 SYSCTL_DESCR("Assign random ip_id values"), 2399 NULL, 0, &ip_do_randomid, 0, 2400 CTL_NET, PF_INET, IPPROTO_IP, 2401 IPCTL_RANDOMID, CTL_EOL); 2402 sysctl_createv(clog, 0, NULL, NULL, 2403 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2404 CTLTYPE_INT, "do_loopback_cksum", 2405 SYSCTL_DESCR("Perform IP checksum on loopback"), 2406 NULL, 0, &ip_do_loopback_cksum, 0, 2407 CTL_NET, PF_INET, IPPROTO_IP, 2408 IPCTL_LOOPBACKCKSUM, CTL_EOL); 2409 sysctl_createv(clog, 0, NULL, NULL, 2410 CTLFLAG_PERMANENT, 2411 CTLTYPE_STRUCT, "stats", 2412 SYSCTL_DESCR("IP statistics"), 2413 sysctl_net_inet_ip_stats, 0, NULL, 0, 2414 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS, 2415 CTL_EOL); 2416 } 2417 2418 void 2419 ip_statinc(u_int stat) 2420 { 2421 2422 KASSERT(stat < IP_NSTATS); 2423 IP_STATINC(stat); 2424 } 2425
Indexes created Wed Sep 24 15:09:51 GMT 2025