1 /* $NetBSD: ip_input.c,v 1.279 2009/03/18 17:06:52 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 1.279 2009/03/18 17:06:52 cegger Exp $"); 95 96 #include "opt_inet.h" 97 #include "opt_compat_netbsd.h" 98 #include "opt_gateway.h" 99 #include "opt_pfil_hooks.h" 100 #include "opt_ipsec.h" 101 #include "opt_mrouting.h" 102 #include "opt_mbuftrace.h" 103 #include "opt_inet_csum.h" 104 105 #include <sys/param.h> 106 #include <sys/systm.h> 107 #include <sys/malloc.h> 108 #include <sys/mbuf.h> 109 #include <sys/domain.h> 110 #include <sys/protosw.h> 111 #include <sys/socket.h> 112 #include <sys/socketvar.h> 113 #include <sys/errno.h> 114 #include <sys/time.h> 115 #include <sys/kernel.h> 116 #include <sys/pool.h> 117 #include <sys/sysctl.h> 118 #include <sys/kauth.h> 119 120 #include <net/if.h> 121 #include <net/if_dl.h> 122 #include <net/route.h> 123 #include <net/pfil.h> 124 125 #include <netinet/in.h> 126 #include <netinet/in_systm.h> 127 #include <netinet/ip.h> 128 #include <netinet/in_pcb.h> 129 #include <netinet/in_proto.h> 130 #include <netinet/in_var.h> 131 #include <netinet/ip_var.h> 132 #include <netinet/ip_private.h> 133 #include <netinet/ip_icmp.h> 134 /* just for gif_ttl */ 135 #include <netinet/in_gif.h> 136 #include "gif.h" 137 #include <net/if_gre.h> 138 #include "gre.h" 139 140 #ifdef MROUTING 141 #include <netinet/ip_mroute.h> 142 #endif 143 144 #ifdef IPSEC 145 #include <netinet6/ipsec.h> 146 #include <netinet6/ipsec_private.h> 147 #include <netkey/key.h> 148 #endif 149 #ifdef FAST_IPSEC 150 #include <netipsec/ipsec.h> 151 #include <netipsec/key.h> 152 #endif /* FAST_IPSEC*/ 153 154 #ifndef IPFORWARDING 155 #ifdef GATEWAY 156 #define IPFORWARDING 1 /* forward IP packets not for us */ 157 #else /* GATEWAY */ 158 #define IPFORWARDING 0 /* don't forward IP packets not for us */ 159 #endif /* GATEWAY */ 160 #endif /* IPFORWARDING */ 161 #ifndef IPSENDREDIRECTS 162 #define IPSENDREDIRECTS 1 163 #endif 164 #ifndef IPFORWSRCRT 165 #define IPFORWSRCRT 1 /* forward source-routed packets */ 166 #endif 167 #ifndef IPALLOWSRCRT 168 #define IPALLOWSRCRT 1 /* allow source-routed packets */ 169 #endif 170 #ifndef IPMTUDISC 171 #define IPMTUDISC 1 172 #endif 173 #ifndef IPMTUDISCTIMEOUT 174 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 175 #endif 176 177 #ifdef COMPAT_50 178 #include <compat/sys/time.h> 179 #include <compat/sys/socket.h> 180 #endif 181 182 /* 183 * Note: DIRECTED_BROADCAST is handled this way so that previous 184 * configuration using this option will Just Work. 185 */ 186 #ifndef IPDIRECTEDBCAST 187 #ifdef DIRECTED_BROADCAST 188 #define IPDIRECTEDBCAST 1 189 #else 190 #define IPDIRECTEDBCAST 0 191 #endif /* DIRECTED_BROADCAST */ 192 #endif /* IPDIRECTEDBCAST */ 193 int ipforwarding = IPFORWARDING; 194 int ipsendredirects = IPSENDREDIRECTS; 195 int ip_defttl = IPDEFTTL; 196 int ip_forwsrcrt = IPFORWSRCRT; 197 int ip_directedbcast = IPDIRECTEDBCAST; 198 int ip_allowsrcrt = IPALLOWSRCRT; 199 int ip_mtudisc = IPMTUDISC; 200 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 201 #ifdef DIAGNOSTIC 202 int ipprintfs = 0; 203 #endif 204 205 int ip_do_randomid = 0; 206 207 /* 208 * XXX - Setting ip_checkinterface mostly implements the receive side of 209 * the Strong ES model described in RFC 1122, but since the routing table 210 * and transmit implementation do not implement the Strong ES model, 211 * setting this to 1 results in an odd hybrid. 212 * 213 * XXX - ip_checkinterface currently must be disabled if you use ipnat 214 * to translate the destination address to another local interface. 215 * 216 * XXX - ip_checkinterface must be disabled if you add IP aliases 217 * to the loopback interface instead of the interface where the 218 * packets for those addresses are received. 219 */ 220 int ip_checkinterface = 0; 221 222 223 struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 224 225 int ipqmaxlen = IFQ_MAXLEN; 226 u_long in_ifaddrhash; /* size of hash table - 1 */ 227 int in_ifaddrentries; /* total number of addrs */ 228 struct in_ifaddrhead in_ifaddrhead; 229 struct in_ifaddrhashhead *in_ifaddrhashtbl; 230 u_long in_multihash; /* size of hash table - 1 */ 231 int in_multientries; /* total number of addrs */ 232 struct in_multihashhead *in_multihashtbl; 233 struct ifqueue ipintrq; 234 uint16_t ip_id; 235 236 percpu_t *ipstat_percpu; 237 238 #ifdef PFIL_HOOKS 239 struct pfil_head inet_pfil_hook; 240 #endif 241 242 /* 243 * Cached copy of nmbclusters. If nbclusters is different, 244 * recalculate IP parameters derived from nmbclusters. 245 */ 246 static int ip_nmbclusters; /* copy of nmbclusters */ 247 static void ip_nmbclusters_changed(void); /* recalc limits */ 248 249 #define CHECK_NMBCLUSTER_PARAMS() \ 250 do { \ 251 if (__predict_false(ip_nmbclusters != nmbclusters)) \ 252 ip_nmbclusters_changed(); \ 253 } while (/*CONSTCOND*/0) 254 255 /* IP datagram reassembly queues (hashed) */ 256 #define IPREASS_NHASH_LOG2 6 257 #define IPREASS_NHASH (1 << IPREASS_NHASH_LOG2) 258 #define IPREASS_HMASK (IPREASS_NHASH - 1) 259 #define IPREASS_HASH(x,y) \ 260 (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK) 261 struct ipqhead ipq[IPREASS_NHASH]; 262 int ipq_locked; 263 static int ip_nfragpackets; /* packets in reass queue */ 264 static int ip_nfrags; /* total fragments in reass queues */ 265 266 int ip_maxfragpackets = 200; /* limit on packets. XXX sysctl */ 267 int ip_maxfrags; /* limit on fragments. XXX sysctl */ 268 269 270 /* 271 * Additive-Increase/Multiplicative-Decrease (AIMD) strategy for 272 * IP reassembly queue buffer managment. 273 * 274 * We keep a count of total IP fragments (NB: not fragmented packets!) 275 * awaiting reassembly (ip_nfrags) and a limit (ip_maxfrags) on fragments. 276 * If ip_nfrags exceeds ip_maxfrags the limit, we drop half the 277 * total fragments in reassembly queues.This AIMD policy avoids 278 * repeatedly deleting single packets under heavy fragmentation load 279 * (e.g., from lossy NFS peers). 280 */ 281 static u_int ip_reass_ttl_decr(u_int ticks); 282 static void ip_reass_drophalf(void); 283 284 285 static inline int ipq_lock_try(void); 286 static inline void ipq_unlock(void); 287 288 static inline int 289 ipq_lock_try(void) 290 { 291 int s; 292 293 /* 294 * Use splvm() -- we're blocking things that would cause 295 * mbuf allocation. 296 */ 297 s = splvm(); 298 if (ipq_locked) { 299 splx(s); 300 return (0); 301 } 302 ipq_locked = 1; 303 splx(s); 304 return (1); 305 } 306 307 static inline void 308 ipq_unlock(void) 309 { 310 int s; 311 312 s = splvm(); 313 ipq_locked = 0; 314 splx(s); 315 } 316 317 #ifdef DIAGNOSTIC 318 #define IPQ_LOCK() \ 319 do { \ 320 if (ipq_lock_try() == 0) { \ 321 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 322 panic("ipq_lock"); \ 323 } \ 324 } while (/*CONSTCOND*/ 0) 325 #define IPQ_LOCK_CHECK() \ 326 do { \ 327 if (ipq_locked == 0) { \ 328 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 329 panic("ipq lock check"); \ 330 } \ 331 } while (/*CONSTCOND*/ 0) 332 #else 333 #define IPQ_LOCK() (void) ipq_lock_try() 334 #define IPQ_LOCK_CHECK() /* nothing */ 335 #endif 336 337 #define IPQ_UNLOCK() ipq_unlock() 338 339 struct pool inmulti_pool; 340 struct pool ipqent_pool; 341 342 #ifdef INET_CSUM_COUNTERS 343 #include <sys/device.h> 344 345 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 346 NULL, "inet", "hwcsum bad"); 347 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 348 NULL, "inet", "hwcsum ok"); 349 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 350 NULL, "inet", "swcsum"); 351 352 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 353 354 EVCNT_ATTACH_STATIC(ip_hwcsum_bad); 355 EVCNT_ATTACH_STATIC(ip_hwcsum_ok); 356 EVCNT_ATTACH_STATIC(ip_swcsum); 357 358 #else 359 360 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 361 362 #endif /* INET_CSUM_COUNTERS */ 363 364 /* 365 * We need to save the IP options in case a protocol wants to respond 366 * to an incoming packet over the same route if the packet got here 367 * using IP source routing. This allows connection establishment and 368 * maintenance when the remote end is on a network that is not known 369 * to us. 370 */ 371 int ip_nhops = 0; 372 static struct ip_srcrt { 373 struct in_addr dst; /* final destination */ 374 char nop; /* one NOP to align */ 375 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 376 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 377 } ip_srcrt; 378 379 static void save_rte(u_char *, struct in_addr); 380 381 #ifdef MBUFTRACE 382 struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx"); 383 struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx"); 384 #endif 385 386 /* 387 * Compute IP limits derived from the value of nmbclusters. 388 */ 389 static void 390 ip_nmbclusters_changed(void) 391 { 392 ip_maxfrags = nmbclusters / 4; 393 ip_nmbclusters = nmbclusters; 394 } 395 396 /* 397 * IP initialization: fill in IP protocol switch table. 398 * All protocols not implemented in kernel go to raw IP protocol handler. 399 */ 400 void 401 ip_init(void) 402 { 403 const struct protosw *pr; 404 int i; 405 406 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", 407 NULL, IPL_SOFTNET); 408 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 409 NULL, IPL_VM); 410 411 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 412 if (pr == 0) 413 panic("ip_init"); 414 for (i = 0; i < IPPROTO_MAX; i++) 415 ip_protox[i] = pr - inetsw; 416 for (pr = inetdomain.dom_protosw; 417 pr < inetdomain.dom_protoswNPROTOSW; pr++) 418 if (pr->pr_domain->dom_family == PF_INET && 419 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 420 ip_protox[pr->pr_protocol] = pr - inetsw; 421 422 for (i = 0; i < IPREASS_NHASH; i++) 423 LIST_INIT(&ipq[i]); 424 425 ip_initid(); 426 ip_id = time_second & 0xfffff; 427 428 ipintrq.ifq_maxlen = ipqmaxlen; 429 ip_nmbclusters_changed(); 430 431 TAILQ_INIT(&in_ifaddrhead); 432 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 433 &in_ifaddrhash); 434 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 435 &in_multihash); 436 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 437 #ifdef GATEWAY 438 ipflow_init(ip_hashsize); 439 #endif 440 441 #ifdef PFIL_HOOKS 442 /* Register our Packet Filter hook. */ 443 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 444 inet_pfil_hook.ph_af = AF_INET; 445 i = pfil_head_register(&inet_pfil_hook); 446 if (i != 0) 447 printf("ip_init: WARNING: unable to register pfil hook, " 448 "error %d\n", i); 449 #endif /* PFIL_HOOKS */ 450 451 #ifdef MBUFTRACE 452 MOWNER_ATTACH(&ip_tx_mowner); 453 MOWNER_ATTACH(&ip_rx_mowner); 454 #endif /* MBUFTRACE */ 455 456 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS); 457 } 458 459 struct sockaddr_in ipaddr = { 460 .sin_len = sizeof(ipaddr), 461 .sin_family = AF_INET, 462 }; 463 struct route ipforward_rt; 464 465 /* 466 * IP software interrupt routine 467 */ 468 void 469 ipintr(void) 470 { 471 int s; 472 struct mbuf *m; 473 474 mutex_enter(softnet_lock); 475 KERNEL_LOCK(1, NULL); 476 while (!IF_IS_EMPTY(&ipintrq)) { 477 s = splnet(); 478 IF_DEQUEUE(&ipintrq, m); 479 splx(s); 480 if (m == NULL) 481 break; 482 ip_input(m); 483 } 484 KERNEL_UNLOCK_ONE(NULL); 485 mutex_exit(softnet_lock); 486 } 487 488 /* 489 * Ip input routine. Checksum and byte swap header. If fragmented 490 * try to reassemble. Process options. Pass to next level. 491 */ 492 void 493 ip_input(struct mbuf *m) 494 { 495 struct ip *ip = NULL; 496 struct ipq *fp; 497 struct in_ifaddr *ia; 498 struct ifaddr *ifa; 499 struct ipqent *ipqe; 500 int hlen = 0, mff, len; 501 int downmatch; 502 int checkif; 503 int srcrt = 0; 504 int s; 505 u_int hash; 506 #ifdef FAST_IPSEC 507 struct m_tag *mtag; 508 struct tdb_ident *tdbi; 509 struct secpolicy *sp; 510 int error; 511 #endif /* FAST_IPSEC */ 512 513 MCLAIM(m, &ip_rx_mowner); 514 #ifdef DIAGNOSTIC 515 if ((m->m_flags & M_PKTHDR) == 0) 516 panic("ipintr no HDR"); 517 #endif 518 519 /* 520 * If no IP addresses have been set yet but the interfaces 521 * are receiving, can't do anything with incoming packets yet. 522 */ 523 if (TAILQ_FIRST(&in_ifaddrhead) == 0) 524 goto bad; 525 IP_STATINC(IP_STAT_TOTAL); 526 /* 527 * If the IP header is not aligned, slurp it up into a new 528 * mbuf with space for link headers, in the event we forward 529 * it. Otherwise, if it is aligned, make sure the entire 530 * base IP header is in the first mbuf of the chain. 531 */ 532 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) { 533 if ((m = m_copyup(m, sizeof(struct ip), 534 (max_linkhdr + 3) & ~3)) == NULL) { 535 /* XXXJRT new stat, please */ 536 IP_STATINC(IP_STAT_TOOSMALL); 537 return; 538 } 539 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 540 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 541 IP_STATINC(IP_STAT_TOOSMALL); 542 return; 543 } 544 } 545 ip = mtod(m, struct ip *); 546 if (ip->ip_v != IPVERSION) { 547 IP_STATINC(IP_STAT_BADVERS); 548 goto bad; 549 } 550 hlen = ip->ip_hl << 2; 551 if (hlen < sizeof(struct ip)) { /* minimum header length */ 552 IP_STATINC(IP_STAT_BADHLEN); 553 goto bad; 554 } 555 if (hlen > m->m_len) { 556 if ((m = m_pullup(m, hlen)) == 0) { 557 IP_STATINC(IP_STAT_BADHLEN); 558 return; 559 } 560 ip = mtod(m, struct ip *); 561 } 562 563 /* 564 * RFC1122: packets with a multicast source address are 565 * not allowed. 566 */ 567 if (IN_MULTICAST(ip->ip_src.s_addr)) { 568 IP_STATINC(IP_STAT_BADADDR); 569 goto bad; 570 } 571 572 /* 127/8 must not appear on wire - RFC1122 */ 573 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 574 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 575 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 576 IP_STATINC(IP_STAT_BADADDR); 577 goto bad; 578 } 579 } 580 581 switch (m->m_pkthdr.csum_flags & 582 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 583 M_CSUM_IPv4_BAD)) { 584 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 585 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 586 goto badcsum; 587 588 case M_CSUM_IPv4: 589 /* Checksum was okay. */ 590 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 591 break; 592 593 default: 594 /* 595 * Must compute it ourselves. Maybe skip checksum on 596 * loopback interfaces. 597 */ 598 if (__predict_true(!(m->m_pkthdr.rcvif->if_flags & 599 IFF_LOOPBACK) || ip_do_loopback_cksum)) { 600 INET_CSUM_COUNTER_INCR(&ip_swcsum); 601 if (in_cksum(m, hlen) != 0) 602 goto badcsum; 603 } 604 break; 605 } 606 607 /* Retrieve the packet length. */ 608 len = ntohs(ip->ip_len); 609 610 /* 611 * Check for additional length bogosity 612 */ 613 if (len < hlen) { 614 IP_STATINC(IP_STAT_BADLEN); 615 goto bad; 616 } 617 618 /* 619 * Check that the amount of data in the buffers 620 * is as at least much as the IP header would have us expect. 621 * Trim mbufs if longer than we expect. 622 * Drop packet if shorter than we expect. 623 */ 624 if (m->m_pkthdr.len < len) { 625 IP_STATINC(IP_STAT_TOOSHORT); 626 goto bad; 627 } 628 if (m->m_pkthdr.len > len) { 629 if (m->m_len == m->m_pkthdr.len) { 630 m->m_len = len; 631 m->m_pkthdr.len = len; 632 } else 633 m_adj(m, len - m->m_pkthdr.len); 634 } 635 636 #if defined(IPSEC) 637 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 638 m->m_flags &= ~M_CANFASTFWD; 639 #else 640 /* 641 * Assume that we can create a fast-forward IP flow entry 642 * based on this packet. 643 */ 644 m->m_flags |= M_CANFASTFWD; 645 #endif 646 647 #ifdef PFIL_HOOKS 648 /* 649 * Run through list of hooks for input packets. If there are any 650 * filters which require that additional packets in the flow are 651 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 652 * Note that filters must _never_ set this flag, as another filter 653 * in the list may have previously cleared it. 654 */ 655 /* 656 * let ipfilter look at packet on the wire, 657 * not the decapsulated packet. 658 */ 659 #ifdef IPSEC 660 if (!ipsec_getnhist(m)) 661 #elif defined(FAST_IPSEC) 662 if (!ipsec_indone(m)) 663 #else 664 if (1) 665 #endif 666 { 667 struct in_addr odst; 668 669 odst = ip->ip_dst; 670 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 671 PFIL_IN) != 0) 672 return; 673 if (m == NULL) 674 return; 675 ip = mtod(m, struct ip *); 676 hlen = ip->ip_hl << 2; 677 /* 678 * XXX The setting of "srcrt" here is to prevent ip_forward() 679 * from generating ICMP redirects for packets that have 680 * been redirected by a hook back out on to the same LAN that 681 * they came from and is not an indication that the packet 682 * is being inffluenced by source routing options. This 683 * allows things like 684 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp" 685 * where tlp0 is both on the 1.1.1.0/24 network and is the 686 * default route for hosts on 1.1.1.0/24. Of course this 687 * also requires a "map tlp0 ..." to complete the story. 688 * One might argue whether or not this kind of network config. 689 * should be supported in this manner... 690 */ 691 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 692 } 693 #endif /* PFIL_HOOKS */ 694 695 #ifdef ALTQ 696 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 697 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 698 /* packet dropped by traffic conditioner */ 699 return; 700 } 701 #endif 702 703 /* 704 * Process options and, if not destined for us, 705 * ship it on. ip_dooptions returns 1 when an 706 * error was detected (causing an icmp message 707 * to be sent and the original packet to be freed). 708 */ 709 ip_nhops = 0; /* for source routed packets */ 710 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 711 return; 712 713 /* 714 * Enable a consistency check between the destination address 715 * and the arrival interface for a unicast packet (the RFC 1122 716 * strong ES model) if IP forwarding is disabled and the packet 717 * is not locally generated. 718 * 719 * XXX - Checking also should be disabled if the destination 720 * address is ipnat'ed to a different interface. 721 * 722 * XXX - Checking is incompatible with IP aliases added 723 * to the loopback interface instead of the interface where 724 * the packets are received. 725 * 726 * XXX - We need to add a per ifaddr flag for this so that 727 * we get finer grain control. 728 */ 729 checkif = ip_checkinterface && (ipforwarding == 0) && 730 (m->m_pkthdr.rcvif != NULL) && 731 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 732 733 /* 734 * Check our list of addresses, to see if the packet is for us. 735 * 736 * Traditional 4.4BSD did not consult IFF_UP at all. 737 * The behavior here is to treat addresses on !IFF_UP interface 738 * as not mine. 739 */ 740 downmatch = 0; 741 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 742 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 743 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 744 continue; 745 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 746 break; 747 else 748 downmatch++; 749 } 750 } 751 if (ia != NULL) 752 goto ours; 753 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 754 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 755 if (ifa->ifa_addr->sa_family != AF_INET) 756 continue; 757 ia = ifatoia(ifa); 758 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 759 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 760 /* 761 * Look for all-0's host part (old broadcast addr), 762 * either for subnet or net. 763 */ 764 ip->ip_dst.s_addr == ia->ia_subnet || 765 ip->ip_dst.s_addr == ia->ia_net) 766 goto ours; 767 /* 768 * An interface with IP address zero accepts 769 * all packets that arrive on that interface. 770 */ 771 if (in_nullhost(ia->ia_addr.sin_addr)) 772 goto ours; 773 } 774 } 775 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 776 struct in_multi *inm; 777 #ifdef MROUTING 778 extern struct socket *ip_mrouter; 779 780 if (ip_mrouter) { 781 /* 782 * If we are acting as a multicast router, all 783 * incoming multicast packets are passed to the 784 * kernel-level multicast forwarding function. 785 * The packet is returned (relatively) intact; if 786 * ip_mforward() returns a non-zero value, the packet 787 * must be discarded, else it may be accepted below. 788 * 789 * (The IP ident field is put in the same byte order 790 * as expected when ip_mforward() is called from 791 * ip_output().) 792 */ 793 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 794 IP_STATINC(IP_STAT_CANTFORWARD); 795 m_freem(m); 796 return; 797 } 798 799 /* 800 * The process-level routing demon needs to receive 801 * all multicast IGMP packets, whether or not this 802 * host belongs to their destination groups. 803 */ 804 if (ip->ip_p == IPPROTO_IGMP) 805 goto ours; 806 IP_STATINC(IP_STAT_CANTFORWARD); 807 } 808 #endif 809 /* 810 * See if we belong to the destination multicast group on the 811 * arrival interface. 812 */ 813 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 814 if (inm == NULL) { 815 IP_STATINC(IP_STAT_CANTFORWARD); 816 m_freem(m); 817 return; 818 } 819 goto ours; 820 } 821 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 822 in_nullhost(ip->ip_dst)) 823 goto ours; 824 825 /* 826 * Not for us; forward if possible and desirable. 827 */ 828 if (ipforwarding == 0) { 829 IP_STATINC(IP_STAT_CANTFORWARD); 830 m_freem(m); 831 } else { 832 /* 833 * If ip_dst matched any of my address on !IFF_UP interface, 834 * and there's no IFF_UP interface that matches ip_dst, 835 * send icmp unreach. Forwarding it will result in in-kernel 836 * forwarding loop till TTL goes to 0. 837 */ 838 if (downmatch) { 839 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 840 IP_STATINC(IP_STAT_CANTFORWARD); 841 return; 842 } 843 #ifdef IPSEC 844 if (ipsec4_in_reject(m, NULL)) { 845 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 846 goto bad; 847 } 848 #endif 849 #ifdef FAST_IPSEC 850 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 851 s = splsoftnet(); 852 if (mtag != NULL) { 853 tdbi = (struct tdb_ident *)(mtag + 1); 854 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 855 } else { 856 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 857 IP_FORWARDING, &error); 858 } 859 if (sp == NULL) { /* NB: can happen if error */ 860 splx(s); 861 /*XXX error stat???*/ 862 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/ 863 goto bad; 864 } 865 866 /* 867 * Check security policy against packet attributes. 868 */ 869 error = ipsec_in_reject(sp, m); 870 KEY_FREESP(&sp); 871 splx(s); 872 if (error) { 873 IP_STATINC(IP_STAT_CANTFORWARD); 874 goto bad; 875 } 876 877 /* 878 * Peek at the outbound SP for this packet to determine if 879 * it's a Fast Forward candidate. 880 */ 881 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 882 if (mtag != NULL) 883 m->m_flags &= ~M_CANFASTFWD; 884 else { 885 s = splsoftnet(); 886 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, 887 (IP_FORWARDING | 888 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 889 &error, NULL); 890 if (sp != NULL) { 891 m->m_flags &= ~M_CANFASTFWD; 892 KEY_FREESP(&sp); 893 } 894 splx(s); 895 } 896 #endif /* FAST_IPSEC */ 897 898 ip_forward(m, srcrt); 899 } 900 return; 901 902 ours: 903 /* 904 * If offset or IP_MF are set, must reassemble. 905 * Otherwise, nothing need be done. 906 * (We could look in the reassembly queue to see 907 * if the packet was previously fragmented, 908 * but it's not worth the time; just let them time out.) 909 */ 910 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 911 uint16_t off; 912 /* 913 * Prevent TCP blind data attacks by not allowing non-initial 914 * fragments to start at less than 68 bytes (minimal fragment 915 * size) and making sure the first fragment is at least 68 916 * bytes. 917 */ 918 off = (ntohs(ip->ip_off) & IP_OFFMASK) << 3; 919 if ((off > 0 ? off + hlen : len) < IP_MINFRAGSIZE - 1) { 920 IP_STATINC(IP_STAT_BADFRAGS); 921 goto bad; 922 } 923 /* 924 * Look for queue of fragments 925 * of this datagram. 926 */ 927 IPQ_LOCK(); 928 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id); 929 LIST_FOREACH(fp, &ipq[hash], ipq_q) { 930 if (ip->ip_id == fp->ipq_id && 931 in_hosteq(ip->ip_src, fp->ipq_src) && 932 in_hosteq(ip->ip_dst, fp->ipq_dst) && 933 ip->ip_p == fp->ipq_p) { 934 /* 935 * Make sure the TOS is matches previous 936 * fragments. 937 */ 938 if (ip->ip_tos != fp->ipq_tos) { 939 IP_STATINC(IP_STAT_BADFRAGS); 940 IPQ_UNLOCK(); 941 goto bad; 942 } 943 goto found; 944 } 945 } 946 fp = 0; 947 found: 948 949 /* 950 * Adjust ip_len to not reflect header, 951 * set ipqe_mff if more fragments are expected, 952 * convert offset of this to bytes. 953 */ 954 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 955 mff = (ip->ip_off & htons(IP_MF)) != 0; 956 if (mff) { 957 /* 958 * Make sure that fragments have a data length 959 * that's a non-zero multiple of 8 bytes. 960 */ 961 if (ntohs(ip->ip_len) == 0 || 962 (ntohs(ip->ip_len) & 0x7) != 0) { 963 IP_STATINC(IP_STAT_BADFRAGS); 964 IPQ_UNLOCK(); 965 goto bad; 966 } 967 } 968 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 969 970 /* 971 * If datagram marked as having more fragments 972 * or if this is not the first fragment, 973 * attempt reassembly; if it succeeds, proceed. 974 */ 975 if (mff || ip->ip_off != htons(0)) { 976 IP_STATINC(IP_STAT_FRAGMENTS); 977 s = splvm(); 978 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 979 splx(s); 980 if (ipqe == NULL) { 981 IP_STATINC(IP_STAT_RCVMEMDROP); 982 IPQ_UNLOCK(); 983 goto bad; 984 } 985 ipqe->ipqe_mff = mff; 986 ipqe->ipqe_m = m; 987 ipqe->ipqe_ip = ip; 988 m = ip_reass(ipqe, fp, &ipq[hash]); 989 if (m == 0) { 990 IPQ_UNLOCK(); 991 return; 992 } 993 IP_STATINC(IP_STAT_REASSEMBLED); 994 ip = mtod(m, struct ip *); 995 hlen = ip->ip_hl << 2; 996 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 997 } else 998 if (fp) 999 ip_freef(fp); 1000 IPQ_UNLOCK(); 1001 } 1002 1003 #if defined(IPSEC) 1004 /* 1005 * enforce IPsec policy checking if we are seeing last header. 1006 * note that we do not visit this with protocols with pcb layer 1007 * code - like udp/tcp/raw ip. 1008 */ 1009 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 1010 ipsec4_in_reject(m, NULL)) { 1011 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1012 goto bad; 1013 } 1014 #endif 1015 #ifdef FAST_IPSEC 1016 /* 1017 * enforce IPsec policy checking if we are seeing last header. 1018 * note that we do not visit this with protocols with pcb layer 1019 * code - like udp/tcp/raw ip. 1020 */ 1021 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 1022 /* 1023 * Check if the packet has already had IPsec processing 1024 * done. If so, then just pass it along. This tag gets 1025 * set during AH, ESP, etc. input handling, before the 1026 * packet is returned to the ip input queue for delivery. 1027 */ 1028 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 1029 s = splsoftnet(); 1030 if (mtag != NULL) { 1031 tdbi = (struct tdb_ident *)(mtag + 1); 1032 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 1033 } else { 1034 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1035 IP_FORWARDING, &error); 1036 } 1037 if (sp != NULL) { 1038 /* 1039 * Check security policy against packet attributes. 1040 */ 1041 error = ipsec_in_reject(sp, m); 1042 KEY_FREESP(&sp); 1043 } else { 1044 /* XXX error stat??? */ 1045 error = EINVAL; 1046 DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 1047 } 1048 splx(s); 1049 if (error) 1050 goto bad; 1051 } 1052 #endif /* FAST_IPSEC */ 1053 1054 /* 1055 * Switch out to protocol's input routine. 1056 */ 1057 #if IFA_STATS 1058 if (ia && ip) 1059 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 1060 #endif 1061 IP_STATINC(IP_STAT_DELIVERED); 1062 { 1063 int off = hlen, nh = ip->ip_p; 1064 1065 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 1066 return; 1067 } 1068 bad: 1069 m_freem(m); 1070 return; 1071 1072 badcsum: 1073 IP_STATINC(IP_STAT_BADSUM); 1074 m_freem(m); 1075 } 1076 1077 /* 1078 * Take incoming datagram fragment and try to 1079 * reassemble it into whole datagram. If a chain for 1080 * reassembly of this datagram already exists, then it 1081 * is given as fp; otherwise have to make a chain. 1082 */ 1083 struct mbuf * 1084 ip_reass(struct ipqent *ipqe, struct ipq *fp, struct ipqhead *ipqhead) 1085 { 1086 struct mbuf *m = ipqe->ipqe_m; 1087 struct ipqent *nq, *p, *q; 1088 struct ip *ip; 1089 struct mbuf *t; 1090 int hlen = ipqe->ipqe_ip->ip_hl << 2; 1091 int i, next, s; 1092 1093 IPQ_LOCK_CHECK(); 1094 1095 /* 1096 * Presence of header sizes in mbufs 1097 * would confuse code below. 1098 */ 1099 m->m_data += hlen; 1100 m->m_len -= hlen; 1101 1102 #ifdef notyet 1103 /* make sure fragment limit is up-to-date */ 1104 CHECK_NMBCLUSTER_PARAMS(); 1105 1106 /* If we have too many fragments, drop the older half. */ 1107 if (ip_nfrags >= ip_maxfrags) 1108 ip_reass_drophalf(void); 1109 #endif 1110 1111 /* 1112 * We are about to add a fragment; increment frag count. 1113 */ 1114 ip_nfrags++; 1115 1116 /* 1117 * If first fragment to arrive, create a reassembly queue. 1118 */ 1119 if (fp == 0) { 1120 /* 1121 * Enforce upper bound on number of fragmented packets 1122 * for which we attempt reassembly; 1123 * If maxfrag is 0, never accept fragments. 1124 * If maxfrag is -1, accept all fragments without limitation. 1125 */ 1126 if (ip_maxfragpackets < 0) 1127 ; 1128 else if (ip_nfragpackets >= ip_maxfragpackets) 1129 goto dropfrag; 1130 ip_nfragpackets++; 1131 fp = malloc(sizeof (struct ipq), M_FTABLE, M_NOWAIT); 1132 if (fp == NULL) 1133 goto dropfrag; 1134 LIST_INSERT_HEAD(ipqhead, fp, ipq_q); 1135 fp->ipq_nfrags = 1; 1136 fp->ipq_ttl = IPFRAGTTL; 1137 fp->ipq_p = ipqe->ipqe_ip->ip_p; 1138 fp->ipq_id = ipqe->ipqe_ip->ip_id; 1139 fp->ipq_tos = ipqe->ipqe_ip->ip_tos; 1140 TAILQ_INIT(&fp->ipq_fragq); 1141 fp->ipq_src = ipqe->ipqe_ip->ip_src; 1142 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 1143 p = NULL; 1144 goto insert; 1145 } else { 1146 fp->ipq_nfrags++; 1147 } 1148 1149 /* 1150 * Find a segment which begins after this one does. 1151 */ 1152 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1153 p = q, q = TAILQ_NEXT(q, ipqe_q)) 1154 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 1155 break; 1156 1157 /* 1158 * If there is a preceding segment, it may provide some of 1159 * our data already. If so, drop the data from the incoming 1160 * segment. If it provides all of our data, drop us. 1161 */ 1162 if (p != NULL) { 1163 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 1164 ntohs(ipqe->ipqe_ip->ip_off); 1165 if (i > 0) { 1166 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 1167 goto dropfrag; 1168 m_adj(ipqe->ipqe_m, i); 1169 ipqe->ipqe_ip->ip_off = 1170 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 1171 ipqe->ipqe_ip->ip_len = 1172 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 1173 } 1174 } 1175 1176 /* 1177 * While we overlap succeeding segments trim them or, 1178 * if they are completely covered, dequeue them. 1179 */ 1180 for (; q != NULL && 1181 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 1182 ntohs(q->ipqe_ip->ip_off); q = nq) { 1183 i = (ntohs(ipqe->ipqe_ip->ip_off) + 1184 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 1185 if (i < ntohs(q->ipqe_ip->ip_len)) { 1186 q->ipqe_ip->ip_len = 1187 htons(ntohs(q->ipqe_ip->ip_len) - i); 1188 q->ipqe_ip->ip_off = 1189 htons(ntohs(q->ipqe_ip->ip_off) + i); 1190 m_adj(q->ipqe_m, i); 1191 break; 1192 } 1193 nq = TAILQ_NEXT(q, ipqe_q); 1194 m_freem(q->ipqe_m); 1195 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1196 s = splvm(); 1197 pool_put(&ipqent_pool, q); 1198 splx(s); 1199 fp->ipq_nfrags--; 1200 ip_nfrags--; 1201 } 1202 1203 insert: 1204 /* 1205 * Stick new segment in its place; 1206 * check for complete reassembly. 1207 */ 1208 if (p == NULL) { 1209 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1210 } else { 1211 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1212 } 1213 next = 0; 1214 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1215 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1216 if (ntohs(q->ipqe_ip->ip_off) != next) 1217 return (0); 1218 next += ntohs(q->ipqe_ip->ip_len); 1219 } 1220 if (p->ipqe_mff) 1221 return (0); 1222 1223 /* 1224 * Reassembly is complete. Check for a bogus message size and 1225 * concatenate fragments. 1226 */ 1227 q = TAILQ_FIRST(&fp->ipq_fragq); 1228 ip = q->ipqe_ip; 1229 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1230 IP_STATINC(IP_STAT_TOOLONG); 1231 ip_freef(fp); 1232 return (0); 1233 } 1234 m = q->ipqe_m; 1235 t = m->m_next; 1236 m->m_next = 0; 1237 m_cat(m, t); 1238 nq = TAILQ_NEXT(q, ipqe_q); 1239 s = splvm(); 1240 pool_put(&ipqent_pool, q); 1241 splx(s); 1242 for (q = nq; q != NULL; q = nq) { 1243 t = q->ipqe_m; 1244 nq = TAILQ_NEXT(q, ipqe_q); 1245 s = splvm(); 1246 pool_put(&ipqent_pool, q); 1247 splx(s); 1248 m_cat(m, t); 1249 } 1250 ip_nfrags -= fp->ipq_nfrags; 1251 1252 /* 1253 * Create header for new ip packet by 1254 * modifying header of first packet; 1255 * dequeue and discard fragment reassembly header. 1256 * Make header visible. 1257 */ 1258 ip->ip_len = htons(next); 1259 ip->ip_src = fp->ipq_src; 1260 ip->ip_dst = fp->ipq_dst; 1261 LIST_REMOVE(fp, ipq_q); 1262 free(fp, M_FTABLE); 1263 ip_nfragpackets--; 1264 m->m_len += (ip->ip_hl << 2); 1265 m->m_data -= (ip->ip_hl << 2); 1266 /* some debugging cruft by sklower, below, will go away soon */ 1267 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1268 int plen = 0; 1269 for (t = m; t; t = t->m_next) 1270 plen += t->m_len; 1271 m->m_pkthdr.len = plen; 1272 m->m_pkthdr.csum_flags = 0; 1273 } 1274 return (m); 1275 1276 dropfrag: 1277 if (fp != 0) 1278 fp->ipq_nfrags--; 1279 ip_nfrags--; 1280 IP_STATINC(IP_STAT_FRAGDROPPED); 1281 m_freem(m); 1282 s = splvm(); 1283 pool_put(&ipqent_pool, ipqe); 1284 splx(s); 1285 return (0); 1286 } 1287 1288 /* 1289 * Free a fragment reassembly header and all 1290 * associated datagrams. 1291 */ 1292 void 1293 ip_freef(struct ipq *fp) 1294 { 1295 struct ipqent *q, *p; 1296 u_int nfrags = 0; 1297 int s; 1298 1299 IPQ_LOCK_CHECK(); 1300 1301 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1302 p = TAILQ_NEXT(q, ipqe_q); 1303 m_freem(q->ipqe_m); 1304 nfrags++; 1305 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1306 s = splvm(); 1307 pool_put(&ipqent_pool, q); 1308 splx(s); 1309 } 1310 1311 if (nfrags != fp->ipq_nfrags) 1312 printf("ip_freef: nfrags %d != %d\n", fp->ipq_nfrags, nfrags); 1313 ip_nfrags -= nfrags; 1314 LIST_REMOVE(fp, ipq_q); 1315 free(fp, M_FTABLE); 1316 ip_nfragpackets--; 1317 } 1318 1319 /* 1320 * IP reassembly TTL machinery for multiplicative drop. 1321 */ 1322 static u_int fragttl_histo[(IPFRAGTTL+1)]; 1323 1324 1325 /* 1326 * Decrement TTL of all reasembly queue entries by `ticks'. 1327 * Count number of distinct fragments (as opposed to partial, fragmented 1328 * datagrams) in the reassembly queue. While we traverse the entire 1329 * reassembly queue, compute and return the median TTL over all fragments. 1330 */ 1331 static u_int 1332 ip_reass_ttl_decr(u_int ticks) 1333 { 1334 u_int nfrags, median, dropfraction, keepfraction; 1335 struct ipq *fp, *nfp; 1336 int i; 1337 1338 nfrags = 0; 1339 memset(fragttl_histo, 0, sizeof fragttl_histo); 1340 1341 for (i = 0; i < IPREASS_NHASH; i++) { 1342 for (fp = LIST_FIRST(&ipq[i]); fp != NULL; fp = nfp) { 1343 fp->ipq_ttl = ((fp->ipq_ttl <= ticks) ? 1344 0 : fp->ipq_ttl - ticks); 1345 nfp = LIST_NEXT(fp, ipq_q); 1346 if (fp->ipq_ttl == 0) { 1347 IP_STATINC(IP_STAT_FRAGTIMEOUT); 1348 ip_freef(fp); 1349 } else { 1350 nfrags += fp->ipq_nfrags; 1351 fragttl_histo[fp->ipq_ttl] += fp->ipq_nfrags; 1352 } 1353 } 1354 } 1355 1356 KASSERT(ip_nfrags == nfrags); 1357 1358 /* Find median (or other drop fraction) in histogram. */ 1359 dropfraction = (ip_nfrags / 2); 1360 keepfraction = ip_nfrags - dropfraction; 1361 for (i = IPFRAGTTL, median = 0; i >= 0; i--) { 1362 median += fragttl_histo[i]; 1363 if (median >= keepfraction) 1364 break; 1365 } 1366 1367 /* Return TTL of median (or other fraction). */ 1368 return (u_int)i; 1369 } 1370 1371 void 1372 ip_reass_drophalf(void) 1373 { 1374 1375 u_int median_ticks; 1376 /* 1377 * Compute median TTL of all fragments, and count frags 1378 * with that TTL or lower (roughly half of all fragments). 1379 */ 1380 median_ticks = ip_reass_ttl_decr(0); 1381 1382 /* Drop half. */ 1383 median_ticks = ip_reass_ttl_decr(median_ticks); 1384 1385 } 1386 1387 /* 1388 * IP timer processing; 1389 * if a timer expires on a reassembly 1390 * queue, discard it. 1391 */ 1392 void 1393 ip_slowtimo(void) 1394 { 1395 static u_int dropscanidx = 0; 1396 u_int i; 1397 u_int median_ttl; 1398 1399 mutex_enter(softnet_lock); 1400 KERNEL_LOCK(1, NULL); 1401 1402 IPQ_LOCK(); 1403 1404 /* Age TTL of all fragments by 1 tick .*/ 1405 median_ttl = ip_reass_ttl_decr(1); 1406 1407 /* make sure fragment limit is up-to-date */ 1408 CHECK_NMBCLUSTER_PARAMS(); 1409 1410 /* If we have too many fragments, drop the older half. */ 1411 if (ip_nfrags > ip_maxfrags) 1412 ip_reass_ttl_decr(median_ttl); 1413 1414 /* 1415 * If we are over the maximum number of fragmented packets 1416 * (due to the limit being lowered), drain off 1417 * enough to get down to the new limit. Start draining 1418 * from the reassembly hashqueue most recently drained. 1419 */ 1420 if (ip_maxfragpackets < 0) 1421 ; 1422 else { 1423 int wrapped = 0; 1424 1425 i = dropscanidx; 1426 while (ip_nfragpackets > ip_maxfragpackets && wrapped == 0) { 1427 while (LIST_FIRST(&ipq[i]) != NULL) 1428 ip_freef(LIST_FIRST(&ipq[i])); 1429 if (++i >= IPREASS_NHASH) { 1430 i = 0; 1431 } 1432 /* 1433 * Dont scan forever even if fragment counters are 1434 * wrong: stop after scanning entire reassembly queue. 1435 */ 1436 if (i == dropscanidx) 1437 wrapped = 1; 1438 } 1439 dropscanidx = i; 1440 } 1441 IPQ_UNLOCK(); 1442 1443 KERNEL_UNLOCK_ONE(NULL); 1444 mutex_exit(softnet_lock); 1445 } 1446 1447 /* 1448 * Drain off all datagram fragments. Don't acquire softnet_lock as 1449 * can be called from hardware interrupt context. 1450 */ 1451 void 1452 ip_drain(void) 1453 { 1454 1455 KERNEL_LOCK(1, NULL); 1456 1457 /* 1458 * We may be called from a device's interrupt context. If 1459 * the ipq is already busy, just bail out now. 1460 */ 1461 if (ipq_lock_try() != 0) { 1462 /* 1463 * Drop half the total fragments now. If more mbufs are 1464 * needed, we will be called again soon. 1465 */ 1466 ip_reass_drophalf(); 1467 IPQ_UNLOCK(); 1468 } 1469 1470 KERNEL_UNLOCK_ONE(NULL); 1471 } 1472 1473 /* 1474 * Do option processing on a datagram, 1475 * possibly discarding it if bad options are encountered, 1476 * or forwarding it if source-routed. 1477 * Returns 1 if packet has been forwarded/freed, 1478 * 0 if the packet should be processed further. 1479 */ 1480 int 1481 ip_dooptions(struct mbuf *m) 1482 { 1483 struct ip *ip = mtod(m, struct ip *); 1484 u_char *cp, *cp0; 1485 struct ip_timestamp *ipt; 1486 struct in_ifaddr *ia; 1487 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1488 struct in_addr dst; 1489 n_time ntime; 1490 1491 dst = ip->ip_dst; 1492 cp = (u_char *)(ip + 1); 1493 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1494 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1495 opt = cp[IPOPT_OPTVAL]; 1496 if (opt == IPOPT_EOL) 1497 break; 1498 if (opt == IPOPT_NOP) 1499 optlen = 1; 1500 else { 1501 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1502 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1503 goto bad; 1504 } 1505 optlen = cp[IPOPT_OLEN]; 1506 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1507 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1508 goto bad; 1509 } 1510 } 1511 switch (opt) { 1512 1513 default: 1514 break; 1515 1516 /* 1517 * Source routing with record. 1518 * Find interface with current destination address. 1519 * If none on this machine then drop if strictly routed, 1520 * or do nothing if loosely routed. 1521 * Record interface address and bring up next address 1522 * component. If strictly routed make sure next 1523 * address is on directly accessible net. 1524 */ 1525 case IPOPT_LSRR: 1526 case IPOPT_SSRR: 1527 if (ip_allowsrcrt == 0) { 1528 type = ICMP_UNREACH; 1529 code = ICMP_UNREACH_NET_PROHIB; 1530 goto bad; 1531 } 1532 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1533 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1534 goto bad; 1535 } 1536 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1537 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1538 goto bad; 1539 } 1540 ipaddr.sin_addr = ip->ip_dst; 1541 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1542 if (ia == 0) { 1543 if (opt == IPOPT_SSRR) { 1544 type = ICMP_UNREACH; 1545 code = ICMP_UNREACH_SRCFAIL; 1546 goto bad; 1547 } 1548 /* 1549 * Loose routing, and not at next destination 1550 * yet; nothing to do except forward. 1551 */ 1552 break; 1553 } 1554 off--; /* 0 origin */ 1555 if ((off + sizeof(struct in_addr)) > optlen) { 1556 /* 1557 * End of source route. Should be for us. 1558 */ 1559 save_rte(cp, ip->ip_src); 1560 break; 1561 } 1562 /* 1563 * locate outgoing interface 1564 */ 1565 memcpy( (void *)&ipaddr.sin_addr, (void *)(cp + off), 1566 sizeof(ipaddr.sin_addr)); 1567 if (opt == IPOPT_SSRR) 1568 ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr))); 1569 else 1570 ia = ip_rtaddr(ipaddr.sin_addr); 1571 if (ia == 0) { 1572 type = ICMP_UNREACH; 1573 code = ICMP_UNREACH_SRCFAIL; 1574 goto bad; 1575 } 1576 ip->ip_dst = ipaddr.sin_addr; 1577 bcopy((void *)&ia->ia_addr.sin_addr, 1578 (void *)(cp + off), sizeof(struct in_addr)); 1579 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1580 /* 1581 * Let ip_intr's mcast routing check handle mcast pkts 1582 */ 1583 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1584 break; 1585 1586 case IPOPT_RR: 1587 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1588 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1589 goto bad; 1590 } 1591 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1592 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1593 goto bad; 1594 } 1595 /* 1596 * If no space remains, ignore. 1597 */ 1598 off--; /* 0 origin */ 1599 if ((off + sizeof(struct in_addr)) > optlen) 1600 break; 1601 memcpy( (void *)&ipaddr.sin_addr, (void *)(&ip->ip_dst), 1602 sizeof(ipaddr.sin_addr)); 1603 /* 1604 * locate outgoing interface; if we're the destination, 1605 * use the incoming interface (should be same). 1606 */ 1607 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1608 == NULL && 1609 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1610 type = ICMP_UNREACH; 1611 code = ICMP_UNREACH_HOST; 1612 goto bad; 1613 } 1614 bcopy((void *)&ia->ia_addr.sin_addr, 1615 (void *)(cp + off), sizeof(struct in_addr)); 1616 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1617 break; 1618 1619 case IPOPT_TS: 1620 code = cp - (u_char *)ip; 1621 ipt = (struct ip_timestamp *)cp; 1622 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1623 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1624 goto bad; 1625 } 1626 if (ipt->ipt_ptr < 5) { 1627 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1628 goto bad; 1629 } 1630 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1631 if (++ipt->ipt_oflw == 0) { 1632 code = (u_char *)&ipt->ipt_ptr - 1633 (u_char *)ip; 1634 goto bad; 1635 } 1636 break; 1637 } 1638 cp0 = (cp + ipt->ipt_ptr - 1); 1639 switch (ipt->ipt_flg) { 1640 1641 case IPOPT_TS_TSONLY: 1642 break; 1643 1644 case IPOPT_TS_TSANDADDR: 1645 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1646 sizeof(struct in_addr) > ipt->ipt_len) { 1647 code = (u_char *)&ipt->ipt_ptr - 1648 (u_char *)ip; 1649 goto bad; 1650 } 1651 ipaddr.sin_addr = dst; 1652 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1653 m->m_pkthdr.rcvif)); 1654 if (ia == 0) 1655 continue; 1656 bcopy(&ia->ia_addr.sin_addr, 1657 cp0, sizeof(struct in_addr)); 1658 ipt->ipt_ptr += sizeof(struct in_addr); 1659 break; 1660 1661 case IPOPT_TS_PRESPEC: 1662 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1663 sizeof(struct in_addr) > ipt->ipt_len) { 1664 code = (u_char *)&ipt->ipt_ptr - 1665 (u_char *)ip; 1666 goto bad; 1667 } 1668 memcpy( &ipaddr.sin_addr, cp0, 1669 sizeof(struct in_addr)); 1670 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1671 == NULL) 1672 continue; 1673 ipt->ipt_ptr += sizeof(struct in_addr); 1674 break; 1675 1676 default: 1677 /* XXX can't take &ipt->ipt_flg */ 1678 code = (u_char *)&ipt->ipt_ptr - 1679 (u_char *)ip + 1; 1680 goto bad; 1681 } 1682 ntime = iptime(); 1683 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1684 memmove((char *)cp + ipt->ipt_ptr - 1, cp0, 1685 sizeof(n_time)); 1686 ipt->ipt_ptr += sizeof(n_time); 1687 } 1688 } 1689 if (forward) { 1690 if (ip_forwsrcrt == 0) { 1691 type = ICMP_UNREACH; 1692 code = ICMP_UNREACH_SRCFAIL; 1693 goto bad; 1694 } 1695 ip_forward(m, 1); 1696 return (1); 1697 } 1698 return (0); 1699 bad: 1700 icmp_error(m, type, code, 0, 0); 1701 IP_STATINC(IP_STAT_BADOPTIONS); 1702 return (1); 1703 } 1704 1705 /* 1706 * Given address of next destination (final or next hop), 1707 * return internet address info of interface to be used to get there. 1708 */ 1709 struct in_ifaddr * 1710 ip_rtaddr(struct in_addr dst) 1711 { 1712 struct rtentry *rt; 1713 union { 1714 struct sockaddr dst; 1715 struct sockaddr_in dst4; 1716 } u; 1717 1718 sockaddr_in_init(&u.dst4, &dst, 0); 1719 1720 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) 1721 return NULL; 1722 1723 return ifatoia(rt->rt_ifa); 1724 } 1725 1726 /* 1727 * Save incoming source route for use in replies, 1728 * to be picked up later by ip_srcroute if the receiver is interested. 1729 */ 1730 void 1731 save_rte(u_char *option, struct in_addr dst) 1732 { 1733 unsigned olen; 1734 1735 olen = option[IPOPT_OLEN]; 1736 #ifdef DIAGNOSTIC 1737 if (ipprintfs) 1738 printf("save_rte: olen %d\n", olen); 1739 #endif /* 0 */ 1740 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1741 return; 1742 memcpy( (void *)ip_srcrt.srcopt, (void *)option, olen); 1743 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1744 ip_srcrt.dst = dst; 1745 } 1746 1747 /* 1748 * Retrieve incoming source route for use in replies, 1749 * in the same form used by setsockopt. 1750 * The first hop is placed before the options, will be removed later. 1751 */ 1752 struct mbuf * 1753 ip_srcroute(void) 1754 { 1755 struct in_addr *p, *q; 1756 struct mbuf *m; 1757 1758 if (ip_nhops == 0) 1759 return NULL; 1760 m = m_get(M_DONTWAIT, MT_SOOPTS); 1761 if (m == 0) 1762 return NULL; 1763 1764 MCLAIM(m, &inetdomain.dom_mowner); 1765 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1766 1767 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1768 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1769 OPTSIZ; 1770 #ifdef DIAGNOSTIC 1771 if (ipprintfs) 1772 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1773 #endif 1774 1775 /* 1776 * First save first hop for return route 1777 */ 1778 p = &ip_srcrt.route[ip_nhops - 1]; 1779 *(mtod(m, struct in_addr *)) = *p--; 1780 #ifdef DIAGNOSTIC 1781 if (ipprintfs) 1782 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1783 #endif 1784 1785 /* 1786 * Copy option fields and padding (nop) to mbuf. 1787 */ 1788 ip_srcrt.nop = IPOPT_NOP; 1789 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1790 memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop, 1791 OPTSIZ); 1792 q = (struct in_addr *)(mtod(m, char *) + 1793 sizeof(struct in_addr) + OPTSIZ); 1794 #undef OPTSIZ 1795 /* 1796 * Record return path as an IP source route, 1797 * reversing the path (pointers are now aligned). 1798 */ 1799 while (p >= ip_srcrt.route) { 1800 #ifdef DIAGNOSTIC 1801 if (ipprintfs) 1802 printf(" %x", ntohl(q->s_addr)); 1803 #endif 1804 *q++ = *p--; 1805 } 1806 /* 1807 * Last hop goes to final destination. 1808 */ 1809 *q = ip_srcrt.dst; 1810 #ifdef DIAGNOSTIC 1811 if (ipprintfs) 1812 printf(" %x\n", ntohl(q->s_addr)); 1813 #endif 1814 return (m); 1815 } 1816 1817 const int inetctlerrmap[PRC_NCMDS] = { 1818 [PRC_MSGSIZE] = EMSGSIZE, 1819 [PRC_HOSTDEAD] = EHOSTDOWN, 1820 [PRC_HOSTUNREACH] = EHOSTUNREACH, 1821 [PRC_UNREACH_NET] = EHOSTUNREACH, 1822 [PRC_UNREACH_HOST] = EHOSTUNREACH, 1823 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED, 1824 [PRC_UNREACH_PORT] = ECONNREFUSED, 1825 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH, 1826 [PRC_PARAMPROB] = ENOPROTOOPT, 1827 }; 1828 1829 /* 1830 * Forward a packet. If some error occurs return the sender 1831 * an icmp packet. Note we can't always generate a meaningful 1832 * icmp message because icmp doesn't have a large enough repertoire 1833 * of codes and types. 1834 * 1835 * If not forwarding, just drop the packet. This could be confusing 1836 * if ipforwarding was zero but some routing protocol was advancing 1837 * us as a gateway to somewhere. However, we must let the routing 1838 * protocol deal with that. 1839 * 1840 * The srcrt parameter indicates whether the packet is being forwarded 1841 * via a source route. 1842 */ 1843 void 1844 ip_forward(struct mbuf *m, int srcrt) 1845 { 1846 struct ip *ip = mtod(m, struct ip *); 1847 struct rtentry *rt; 1848 int error, type = 0, code = 0, destmtu = 0; 1849 struct mbuf *mcopy; 1850 n_long dest; 1851 union { 1852 struct sockaddr dst; 1853 struct sockaddr_in dst4; 1854 } u; 1855 1856 /* 1857 * We are now in the output path. 1858 */ 1859 MCLAIM(m, &ip_tx_mowner); 1860 1861 /* 1862 * Clear any in-bound checksum flags for this packet. 1863 */ 1864 m->m_pkthdr.csum_flags = 0; 1865 1866 dest = 0; 1867 #ifdef DIAGNOSTIC 1868 if (ipprintfs) { 1869 printf("forward: src %s ", inet_ntoa(ip->ip_src)); 1870 printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl); 1871 } 1872 #endif 1873 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1874 IP_STATINC(IP_STAT_CANTFORWARD); 1875 m_freem(m); 1876 return; 1877 } 1878 if (ip->ip_ttl <= IPTTLDEC) { 1879 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1880 return; 1881 } 1882 1883 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0); 1884 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) { 1885 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0); 1886 return; 1887 } 1888 1889 /* 1890 * Save at most 68 bytes of the packet in case 1891 * we need to generate an ICMP message to the src. 1892 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1893 */ 1894 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1895 if (mcopy) 1896 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1897 1898 ip->ip_ttl -= IPTTLDEC; 1899 1900 /* 1901 * If forwarding packet using same interface that it came in on, 1902 * perhaps should send a redirect to sender to shortcut a hop. 1903 * Only send redirect if source is sending directly to us, 1904 * and if packet was not source routed (or has any options). 1905 * Also, don't send redirect if forwarding using a default route 1906 * or a route modified by a redirect. 1907 */ 1908 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1909 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1910 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) && 1911 ipsendredirects && !srcrt) { 1912 if (rt->rt_ifa && 1913 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1914 ifatoia(rt->rt_ifa)->ia_subnet) { 1915 if (rt->rt_flags & RTF_GATEWAY) 1916 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1917 else 1918 dest = ip->ip_dst.s_addr; 1919 /* 1920 * Router requirements says to only send host 1921 * redirects. 1922 */ 1923 type = ICMP_REDIRECT; 1924 code = ICMP_REDIRECT_HOST; 1925 #ifdef DIAGNOSTIC 1926 if (ipprintfs) 1927 printf("redirect (%d) to %x\n", code, 1928 (u_int32_t)dest); 1929 #endif 1930 } 1931 } 1932 1933 error = ip_output(m, NULL, &ipforward_rt, 1934 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1935 (struct ip_moptions *)NULL, (struct socket *)NULL); 1936 1937 if (error) 1938 IP_STATINC(IP_STAT_CANTFORWARD); 1939 else { 1940 uint64_t *ips = IP_STAT_GETREF(); 1941 ips[IP_STAT_FORWARD]++; 1942 if (type) { 1943 ips[IP_STAT_REDIRECTSENT]++; 1944 IP_STAT_PUTREF(); 1945 } else { 1946 IP_STAT_PUTREF(); 1947 if (mcopy) { 1948 #ifdef GATEWAY 1949 if (mcopy->m_flags & M_CANFASTFWD) 1950 ipflow_create(&ipforward_rt, mcopy); 1951 #endif 1952 m_freem(mcopy); 1953 } 1954 return; 1955 } 1956 } 1957 if (mcopy == NULL) 1958 return; 1959 1960 switch (error) { 1961 1962 case 0: /* forwarded, but need redirect */ 1963 /* type, code set above */ 1964 break; 1965 1966 case ENETUNREACH: /* shouldn't happen, checked above */ 1967 case EHOSTUNREACH: 1968 case ENETDOWN: 1969 case EHOSTDOWN: 1970 default: 1971 type = ICMP_UNREACH; 1972 code = ICMP_UNREACH_HOST; 1973 break; 1974 1975 case EMSGSIZE: 1976 type = ICMP_UNREACH; 1977 code = ICMP_UNREACH_NEEDFRAG; 1978 1979 if ((rt = rtcache_validate(&ipforward_rt)) != NULL) 1980 destmtu = rt->rt_ifp->if_mtu; 1981 1982 #if defined(IPSEC) || defined(FAST_IPSEC) 1983 { 1984 /* 1985 * If the packet is routed over IPsec tunnel, tell the 1986 * originator the tunnel MTU. 1987 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1988 * XXX quickhack!!! 1989 */ 1990 1991 struct secpolicy *sp; 1992 int ipsecerror; 1993 size_t ipsechdr; 1994 struct route *ro; 1995 1996 sp = ipsec4_getpolicybyaddr(mcopy, 1997 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1998 &ipsecerror); 1999 2000 if (sp != NULL) { 2001 /* count IPsec header size */ 2002 ipsechdr = ipsec4_hdrsiz(mcopy, 2003 IPSEC_DIR_OUTBOUND, NULL); 2004 2005 /* 2006 * find the correct route for outer IPv4 2007 * header, compute tunnel MTU. 2008 */ 2009 2010 if (sp->req != NULL 2011 && sp->req->sav != NULL 2012 && sp->req->sav->sah != NULL) { 2013 ro = &sp->req->sav->sah->sa_route; 2014 rt = rtcache_validate(ro); 2015 if (rt && rt->rt_ifp) { 2016 destmtu = 2017 rt->rt_rmx.rmx_mtu ? 2018 rt->rt_rmx.rmx_mtu : 2019 rt->rt_ifp->if_mtu; 2020 destmtu -= ipsechdr; 2021 } 2022 } 2023 2024 #ifdef IPSEC 2025 key_freesp(sp); 2026 #else 2027 KEY_FREESP(&sp); 2028 #endif 2029 } 2030 } 2031 #endif /*defined(IPSEC) || defined(FAST_IPSEC)*/ 2032 IP_STATINC(IP_STAT_CANTFRAG); 2033 break; 2034 2035 case ENOBUFS: 2036 #if 1 2037 /* 2038 * a router should not generate ICMP_SOURCEQUENCH as 2039 * required in RFC1812 Requirements for IP Version 4 Routers. 2040 * source quench could be a big problem under DoS attacks, 2041 * or if the underlying interface is rate-limited. 2042 */ 2043 if (mcopy) 2044 m_freem(mcopy); 2045 return; 2046 #else 2047 type = ICMP_SOURCEQUENCH; 2048 code = 0; 2049 break; 2050 #endif 2051 } 2052 icmp_error(mcopy, type, code, dest, destmtu); 2053 } 2054 2055 void 2056 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 2057 struct mbuf *m) 2058 { 2059 2060 if (inp->inp_socket->so_options & SO_TIMESTAMP 2061 #ifdef SO_OTIMESTAMP 2062 || inp->inp_socket->so_options & SO_OTIMESTAMP 2063 #endif 2064 ) { 2065 struct timeval tv; 2066 2067 microtime(&tv); 2068 #ifdef SO_OTIMESTAMP 2069 if (inp->inp_socket->so_options & SO_OTIMESTAMP) { 2070 struct timeval50 tv50; 2071 timeval_to_timeval50(&tv, &tv50); 2072 *mp = sbcreatecontrol((void *) &tv50, sizeof(tv50), 2073 SCM_OTIMESTAMP, SOL_SOCKET); 2074 } else 2075 #endif 2076 *mp = sbcreatecontrol((void *) &tv, sizeof(tv), 2077 SCM_TIMESTAMP, SOL_SOCKET); 2078 if (*mp) 2079 mp = &(*mp)->m_next; 2080 } 2081 if (inp->inp_flags & INP_RECVDSTADDR) { 2082 *mp = sbcreatecontrol((void *) &ip->ip_dst, 2083 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 2084 if (*mp) 2085 mp = &(*mp)->m_next; 2086 } 2087 #ifdef notyet 2088 /* 2089 * XXX 2090 * Moving these out of udp_input() made them even more broken 2091 * than they already were. 2092 * - fenner@parc.xerox.com 2093 */ 2094 /* options were tossed already */ 2095 if (inp->inp_flags & INP_RECVOPTS) { 2096 *mp = sbcreatecontrol((void *) opts_deleted_above, 2097 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 2098 if (*mp) 2099 mp = &(*mp)->m_next; 2100 } 2101 /* ip_srcroute doesn't do what we want here, need to fix */ 2102 if (inp->inp_flags & INP_RECVRETOPTS) { 2103 *mp = sbcreatecontrol((void *) ip_srcroute(), 2104 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 2105 if (*mp) 2106 mp = &(*mp)->m_next; 2107 } 2108 #endif 2109 if (inp->inp_flags & INP_RECVIF) { 2110 struct sockaddr_dl sdl; 2111 2112 sockaddr_dl_init(&sdl, sizeof(sdl), 2113 (m->m_pkthdr.rcvif != NULL) 2114 ? m->m_pkthdr.rcvif->if_index 2115 : 0, 2116 0, NULL, 0, NULL, 0); 2117 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP); 2118 if (*mp) 2119 mp = &(*mp)->m_next; 2120 } 2121 } 2122 2123 /* 2124 * sysctl helper routine for net.inet.ip.forwsrcrt. 2125 */ 2126 static int 2127 sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS) 2128 { 2129 int error, tmp; 2130 struct sysctlnode node; 2131 2132 node = *rnode; 2133 tmp = ip_forwsrcrt; 2134 node.sysctl_data = &tmp; 2135 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2136 if (error || newp == NULL) 2137 return (error); 2138 2139 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT, 2140 0, NULL, NULL, NULL)) 2141 return (EPERM); 2142 2143 ip_forwsrcrt = tmp; 2144 2145 return (0); 2146 } 2147 2148 /* 2149 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the 2150 * range of the new value and tweaks timers if it changes. 2151 */ 2152 static int 2153 sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS) 2154 { 2155 int error, tmp; 2156 struct sysctlnode node; 2157 2158 node = *rnode; 2159 tmp = ip_mtudisc_timeout; 2160 node.sysctl_data = &tmp; 2161 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2162 if (error || newp == NULL) 2163 return (error); 2164 if (tmp < 0) 2165 return (EINVAL); 2166 2167 mutex_enter(softnet_lock); 2168 2169 ip_mtudisc_timeout = tmp; 2170 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 2171 2172 mutex_exit(softnet_lock); 2173 2174 return (0); 2175 } 2176 2177 #ifdef GATEWAY 2178 /* 2179 * sysctl helper routine for net.inet.ip.maxflows. 2180 */ 2181 static int 2182 sysctl_net_inet_ip_maxflows(SYSCTLFN_ARGS) 2183 { 2184 int error; 2185 2186 error = sysctl_lookup(SYSCTLFN_CALL(rnode)); 2187 if (error || newp == NULL) 2188 return (error); 2189 2190 mutex_enter(softnet_lock); 2191 KERNEL_LOCK(1, NULL); 2192 2193 ipflow_prune(); 2194 2195 KERNEL_UNLOCK_ONE(NULL); 2196 mutex_exit(softnet_lock); 2197 2198 return (0); 2199 } 2200 2201 static int 2202 sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS) 2203 { 2204 int error, tmp; 2205 struct sysctlnode node; 2206 2207 node = *rnode; 2208 tmp = ip_hashsize; 2209 node.sysctl_data = &tmp; 2210 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2211 if (error || newp == NULL) 2212 return (error); 2213 2214 if ((tmp & (tmp - 1)) == 0 && tmp != 0) { 2215 /* 2216 * Can only fail due to malloc() 2217 */ 2218 mutex_enter(softnet_lock); 2219 KERNEL_LOCK(1, NULL); 2220 2221 error = ipflow_invalidate_all(tmp); 2222 2223 KERNEL_UNLOCK_ONE(NULL); 2224 mutex_exit(softnet_lock); 2225 2226 } else { 2227 /* 2228 * EINVAL if not a power of 2 2229 */ 2230 error = EINVAL; 2231 } 2232 2233 return error; 2234 } 2235 #endif /* GATEWAY */ 2236 2237 static int 2238 sysctl_net_inet_ip_stats(SYSCTLFN_ARGS) 2239 { 2240 2241 return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS)); 2242 } 2243 2244 SYSCTL_SETUP(sysctl_net_inet_ip_setup, "sysctl net.inet.ip subtree setup") 2245 { 2246 extern int subnetsarelocal, hostzeroisbroadcast; 2247 2248 sysctl_createv(clog, 0, NULL, NULL, 2249 CTLFLAG_PERMANENT, 2250 CTLTYPE_NODE, "net", NULL, 2251 NULL, 0, NULL, 0, 2252 CTL_NET, CTL_EOL); 2253 sysctl_createv(clog, 0, NULL, NULL, 2254 CTLFLAG_PERMANENT, 2255 CTLTYPE_NODE, "inet", 2256 SYSCTL_DESCR("PF_INET related settings"), 2257 NULL, 0, NULL, 0, 2258 CTL_NET, PF_INET, CTL_EOL); 2259 sysctl_createv(clog, 0, NULL, NULL, 2260 CTLFLAG_PERMANENT, 2261 CTLTYPE_NODE, "ip", 2262 SYSCTL_DESCR("IPv4 related settings"), 2263 NULL, 0, NULL, 0, 2264 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL); 2265 2266 sysctl_createv(clog, 0, NULL, NULL, 2267 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2268 CTLTYPE_INT, "forwarding", 2269 SYSCTL_DESCR("Enable forwarding of INET datagrams"), 2270 NULL, 0, &ipforwarding, 0, 2271 CTL_NET, PF_INET, IPPROTO_IP, 2272 IPCTL_FORWARDING, CTL_EOL); 2273 sysctl_createv(clog, 0, NULL, NULL, 2274 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2275 CTLTYPE_INT, "redirect", 2276 SYSCTL_DESCR("Enable sending of ICMP redirect messages"), 2277 NULL, 0, &ipsendredirects, 0, 2278 CTL_NET, PF_INET, IPPROTO_IP, 2279 IPCTL_SENDREDIRECTS, CTL_EOL); 2280 sysctl_createv(clog, 0, NULL, NULL, 2281 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2282 CTLTYPE_INT, "ttl", 2283 SYSCTL_DESCR("Default TTL for an INET datagram"), 2284 NULL, 0, &ip_defttl, 0, 2285 CTL_NET, PF_INET, IPPROTO_IP, 2286 IPCTL_DEFTTL, CTL_EOL); 2287 #ifdef IPCTL_DEFMTU 2288 sysctl_createv(clog, 0, NULL, NULL, 2289 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */, 2290 CTLTYPE_INT, "mtu", 2291 SYSCTL_DESCR("Default MTA for an INET route"), 2292 NULL, 0, &ip_mtu, 0, 2293 CTL_NET, PF_INET, IPPROTO_IP, 2294 IPCTL_DEFMTU, CTL_EOL); 2295 #endif /* IPCTL_DEFMTU */ 2296 sysctl_createv(clog, 0, NULL, NULL, 2297 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2298 CTLTYPE_INT, "forwsrcrt", 2299 SYSCTL_DESCR("Enable forwarding of source-routed " 2300 "datagrams"), 2301 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0, 2302 CTL_NET, PF_INET, IPPROTO_IP, 2303 IPCTL_FORWSRCRT, CTL_EOL); 2304 sysctl_createv(clog, 0, NULL, NULL, 2305 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2306 CTLTYPE_INT, "directed-broadcast", 2307 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"), 2308 NULL, 0, &ip_directedbcast, 0, 2309 CTL_NET, PF_INET, IPPROTO_IP, 2310 IPCTL_DIRECTEDBCAST, CTL_EOL); 2311 sysctl_createv(clog, 0, NULL, NULL, 2312 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2313 CTLTYPE_INT, "allowsrcrt", 2314 SYSCTL_DESCR("Accept source-routed datagrams"), 2315 NULL, 0, &ip_allowsrcrt, 0, 2316 CTL_NET, PF_INET, IPPROTO_IP, 2317 IPCTL_ALLOWSRCRT, CTL_EOL); 2318 sysctl_createv(clog, 0, NULL, NULL, 2319 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2320 CTLTYPE_INT, "subnetsarelocal", 2321 SYSCTL_DESCR("Whether logical subnets are considered " 2322 "local"), 2323 NULL, 0, &subnetsarelocal, 0, 2324 CTL_NET, PF_INET, IPPROTO_IP, 2325 IPCTL_SUBNETSARELOCAL, CTL_EOL); 2326 sysctl_createv(clog, 0, NULL, NULL, 2327 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2328 CTLTYPE_INT, "mtudisc", 2329 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"), 2330 NULL, 0, &ip_mtudisc, 0, 2331 CTL_NET, PF_INET, IPPROTO_IP, 2332 IPCTL_MTUDISC, CTL_EOL); 2333 sysctl_createv(clog, 0, NULL, NULL, 2334 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2335 CTLTYPE_INT, "anonportmin", 2336 SYSCTL_DESCR("Lowest ephemeral port number to assign"), 2337 sysctl_net_inet_ip_ports, 0, &anonportmin, 0, 2338 CTL_NET, PF_INET, IPPROTO_IP, 2339 IPCTL_ANONPORTMIN, CTL_EOL); 2340 sysctl_createv(clog, 0, NULL, NULL, 2341 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2342 CTLTYPE_INT, "anonportmax", 2343 SYSCTL_DESCR("Highest ephemeral port number to assign"), 2344 sysctl_net_inet_ip_ports, 0, &anonportmax, 0, 2345 CTL_NET, PF_INET, IPPROTO_IP, 2346 IPCTL_ANONPORTMAX, CTL_EOL); 2347 sysctl_createv(clog, 0, NULL, NULL, 2348 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2349 CTLTYPE_INT, "mtudisctimeout", 2350 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"), 2351 sysctl_net_inet_ip_pmtudto, 0, &ip_mtudisc_timeout, 0, 2352 CTL_NET, PF_INET, IPPROTO_IP, 2353 IPCTL_MTUDISCTIMEOUT, CTL_EOL); 2354 #ifdef GATEWAY 2355 sysctl_createv(clog, 0, NULL, NULL, 2356 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2357 CTLTYPE_INT, "maxflows", 2358 SYSCTL_DESCR("Number of flows for fast forwarding"), 2359 sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0, 2360 CTL_NET, PF_INET, IPPROTO_IP, 2361 IPCTL_MAXFLOWS, CTL_EOL); 2362 sysctl_createv(clog, 0, NULL, NULL, 2363 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2364 CTLTYPE_INT, "hashsize", 2365 SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"), 2366 sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0, 2367 CTL_NET, PF_INET, IPPROTO_IP, 2368 CTL_CREATE, CTL_EOL); 2369 #endif /* GATEWAY */ 2370 sysctl_createv(clog, 0, NULL, NULL, 2371 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2372 CTLTYPE_INT, "hostzerobroadcast", 2373 SYSCTL_DESCR("All zeroes address is broadcast address"), 2374 NULL, 0, &hostzeroisbroadcast, 0, 2375 CTL_NET, PF_INET, IPPROTO_IP, 2376 IPCTL_HOSTZEROBROADCAST, CTL_EOL); 2377 #if NGIF > 0 2378 sysctl_createv(clog, 0, NULL, NULL, 2379 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2380 CTLTYPE_INT, "gifttl", 2381 SYSCTL_DESCR("Default TTL for a gif tunnel datagram"), 2382 NULL, 0, &ip_gif_ttl, 0, 2383 CTL_NET, PF_INET, IPPROTO_IP, 2384 IPCTL_GIF_TTL, CTL_EOL); 2385 #endif /* NGIF */ 2386 #ifndef IPNOPRIVPORTS 2387 sysctl_createv(clog, 0, NULL, NULL, 2388 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2389 CTLTYPE_INT, "lowportmin", 2390 SYSCTL_DESCR("Lowest privileged ephemeral port number " 2391 "to assign"), 2392 sysctl_net_inet_ip_ports, 0, &lowportmin, 0, 2393 CTL_NET, PF_INET, IPPROTO_IP, 2394 IPCTL_LOWPORTMIN, CTL_EOL); 2395 sysctl_createv(clog, 0, NULL, NULL, 2396 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2397 CTLTYPE_INT, "lowportmax", 2398 SYSCTL_DESCR("Highest privileged ephemeral port number " 2399 "to assign"), 2400 sysctl_net_inet_ip_ports, 0, &lowportmax, 0, 2401 CTL_NET, PF_INET, IPPROTO_IP, 2402 IPCTL_LOWPORTMAX, CTL_EOL); 2403 #endif /* IPNOPRIVPORTS */ 2404 sysctl_createv(clog, 0, NULL, NULL, 2405 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2406 CTLTYPE_INT, "maxfragpackets", 2407 SYSCTL_DESCR("Maximum number of fragments to retain for " 2408 "possible reassembly"), 2409 NULL, 0, &ip_maxfragpackets, 0, 2410 CTL_NET, PF_INET, IPPROTO_IP, 2411 IPCTL_MAXFRAGPACKETS, CTL_EOL); 2412 #if NGRE > 0 2413 sysctl_createv(clog, 0, NULL, NULL, 2414 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2415 CTLTYPE_INT, "grettl", 2416 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"), 2417 NULL, 0, &ip_gre_ttl, 0, 2418 CTL_NET, PF_INET, IPPROTO_IP, 2419 IPCTL_GRE_TTL, CTL_EOL); 2420 #endif /* NGRE */ 2421 sysctl_createv(clog, 0, NULL, NULL, 2422 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2423 CTLTYPE_INT, "checkinterface", 2424 SYSCTL_DESCR("Enable receive side of Strong ES model " 2425 "from RFC1122"), 2426 NULL, 0, &ip_checkinterface, 0, 2427 CTL_NET, PF_INET, IPPROTO_IP, 2428 IPCTL_CHECKINTERFACE, CTL_EOL); 2429 sysctl_createv(clog, 0, NULL, NULL, 2430 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2431 CTLTYPE_INT, "random_id", 2432 SYSCTL_DESCR("Assign random ip_id values"), 2433 NULL, 0, &ip_do_randomid, 0, 2434 CTL_NET, PF_INET, IPPROTO_IP, 2435 IPCTL_RANDOMID, CTL_EOL); 2436 sysctl_createv(clog, 0, NULL, NULL, 2437 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2438 CTLTYPE_INT, "do_loopback_cksum", 2439 SYSCTL_DESCR("Perform IP checksum on loopback"), 2440 NULL, 0, &ip_do_loopback_cksum, 0, 2441 CTL_NET, PF_INET, IPPROTO_IP, 2442 IPCTL_LOOPBACKCKSUM, CTL_EOL); 2443 sysctl_createv(clog, 0, NULL, NULL, 2444 CTLFLAG_PERMANENT, 2445 CTLTYPE_STRUCT, "stats", 2446 SYSCTL_DESCR("IP statistics"), 2447 sysctl_net_inet_ip_stats, 0, NULL, 0, 2448 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS, 2449 CTL_EOL); 2450 } 2451 2452 void 2453 ip_statinc(u_int stat) 2454 { 2455 2456 KASSERT(stat < IP_NSTATS); 2457 IP_STATINC(stat); 2458 } 2459