1 /* $NetBSD: ip_input.c,v 1.284 2009/09/16 15:23:05 pooka 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 1.284 2009/09/16 15:23:05 pooka 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 static void sysctl_net_inet_ip_setup(struct sysctllog **); 387 388 /* 389 * Compute IP limits derived from the value of nmbclusters. 390 */ 391 static void 392 ip_nmbclusters_changed(void) 393 { 394 ip_maxfrags = nmbclusters / 4; 395 ip_nmbclusters = nmbclusters; 396 } 397 398 /* 399 * IP initialization: fill in IP protocol switch table. 400 * All protocols not implemented in kernel go to raw IP protocol handler. 401 */ 402 void 403 ip_init(void) 404 { 405 const struct protosw *pr; 406 int i; 407 408 sysctl_net_inet_ip_setup(NULL); 409 410 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", 411 NULL, IPL_SOFTNET); 412 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 413 NULL, IPL_VM); 414 415 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 416 if (pr == 0) 417 panic("ip_init"); 418 for (i = 0; i < IPPROTO_MAX; i++) 419 ip_protox[i] = pr - inetsw; 420 for (pr = inetdomain.dom_protosw; 421 pr < inetdomain.dom_protoswNPROTOSW; pr++) 422 if (pr->pr_domain->dom_family == PF_INET && 423 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 424 ip_protox[pr->pr_protocol] = pr - inetsw; 425 426 for (i = 0; i < IPREASS_NHASH; i++) 427 LIST_INIT(&ipq[i]); 428 429 ip_initid(); 430 ip_id = time_second & 0xfffff; 431 432 ipintrq.ifq_maxlen = ipqmaxlen; 433 ip_nmbclusters_changed(); 434 435 TAILQ_INIT(&in_ifaddrhead); 436 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 437 &in_ifaddrhash); 438 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true, 439 &in_multihash); 440 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 441 #ifdef GATEWAY 442 ipflow_init(ip_hashsize); 443 #endif 444 445 #ifdef PFIL_HOOKS 446 /* Register our Packet Filter hook. */ 447 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 448 inet_pfil_hook.ph_af = AF_INET; 449 i = pfil_head_register(&inet_pfil_hook); 450 if (i != 0) 451 printf("ip_init: WARNING: unable to register pfil hook, " 452 "error %d\n", i); 453 #endif /* PFIL_HOOKS */ 454 455 #ifdef MBUFTRACE 456 MOWNER_ATTACH(&ip_tx_mowner); 457 MOWNER_ATTACH(&ip_rx_mowner); 458 #endif /* MBUFTRACE */ 459 460 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS); 461 } 462 463 struct sockaddr_in ipaddr = { 464 .sin_len = sizeof(ipaddr), 465 .sin_family = AF_INET, 466 }; 467 struct route ipforward_rt; 468 469 /* 470 * IP software interrupt routine 471 */ 472 void 473 ipintr(void) 474 { 475 int s; 476 struct mbuf *m; 477 478 mutex_enter(softnet_lock); 479 KERNEL_LOCK(1, NULL); 480 while (!IF_IS_EMPTY(&ipintrq)) { 481 s = splnet(); 482 IF_DEQUEUE(&ipintrq, m); 483 splx(s); 484 if (m == NULL) 485 break; 486 ip_input(m); 487 } 488 KERNEL_UNLOCK_ONE(NULL); 489 mutex_exit(softnet_lock); 490 } 491 492 /* 493 * Ip input routine. Checksum and byte swap header. If fragmented 494 * try to reassemble. Process options. Pass to next level. 495 */ 496 void 497 ip_input(struct mbuf *m) 498 { 499 struct ip *ip = NULL; 500 struct ipq *fp; 501 struct in_ifaddr *ia; 502 struct ifaddr *ifa; 503 struct ipqent *ipqe; 504 int hlen = 0, mff, len; 505 int downmatch; 506 int checkif; 507 int srcrt = 0; 508 int s; 509 u_int hash; 510 #ifdef FAST_IPSEC 511 struct m_tag *mtag; 512 struct tdb_ident *tdbi; 513 struct secpolicy *sp; 514 int error; 515 #endif /* FAST_IPSEC */ 516 517 MCLAIM(m, &ip_rx_mowner); 518 #ifdef DIAGNOSTIC 519 if ((m->m_flags & M_PKTHDR) == 0) 520 panic("ipintr no HDR"); 521 #endif 522 523 /* 524 * If no IP addresses have been set yet but the interfaces 525 * are receiving, can't do anything with incoming packets yet. 526 */ 527 if (TAILQ_FIRST(&in_ifaddrhead) == 0) 528 goto bad; 529 IP_STATINC(IP_STAT_TOTAL); 530 /* 531 * If the IP header is not aligned, slurp it up into a new 532 * mbuf with space for link headers, in the event we forward 533 * it. Otherwise, if it is aligned, make sure the entire 534 * base IP header is in the first mbuf of the chain. 535 */ 536 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) { 537 if ((m = m_copyup(m, sizeof(struct ip), 538 (max_linkhdr + 3) & ~3)) == NULL) { 539 /* XXXJRT new stat, please */ 540 IP_STATINC(IP_STAT_TOOSMALL); 541 return; 542 } 543 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 544 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 545 IP_STATINC(IP_STAT_TOOSMALL); 546 return; 547 } 548 } 549 ip = mtod(m, struct ip *); 550 if (ip->ip_v != IPVERSION) { 551 IP_STATINC(IP_STAT_BADVERS); 552 goto bad; 553 } 554 hlen = ip->ip_hl << 2; 555 if (hlen < sizeof(struct ip)) { /* minimum header length */ 556 IP_STATINC(IP_STAT_BADHLEN); 557 goto bad; 558 } 559 if (hlen > m->m_len) { 560 if ((m = m_pullup(m, hlen)) == 0) { 561 IP_STATINC(IP_STAT_BADHLEN); 562 return; 563 } 564 ip = mtod(m, struct ip *); 565 } 566 567 /* 568 * RFC1122: packets with a multicast source address are 569 * not allowed. 570 */ 571 if (IN_MULTICAST(ip->ip_src.s_addr)) { 572 IP_STATINC(IP_STAT_BADADDR); 573 goto bad; 574 } 575 576 /* 127/8 must not appear on wire - RFC1122 */ 577 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 578 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 579 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 580 IP_STATINC(IP_STAT_BADADDR); 581 goto bad; 582 } 583 } 584 585 switch (m->m_pkthdr.csum_flags & 586 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 587 M_CSUM_IPv4_BAD)) { 588 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 589 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 590 goto badcsum; 591 592 case M_CSUM_IPv4: 593 /* Checksum was okay. */ 594 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 595 break; 596 597 default: 598 /* 599 * Must compute it ourselves. Maybe skip checksum on 600 * loopback interfaces. 601 */ 602 if (__predict_true(!(m->m_pkthdr.rcvif->if_flags & 603 IFF_LOOPBACK) || ip_do_loopback_cksum)) { 604 INET_CSUM_COUNTER_INCR(&ip_swcsum); 605 if (in_cksum(m, hlen) != 0) 606 goto badcsum; 607 } 608 break; 609 } 610 611 /* Retrieve the packet length. */ 612 len = ntohs(ip->ip_len); 613 614 /* 615 * Check for additional length bogosity 616 */ 617 if (len < hlen) { 618 IP_STATINC(IP_STAT_BADLEN); 619 goto bad; 620 } 621 622 /* 623 * Check that the amount of data in the buffers 624 * is as at least much as the IP header would have us expect. 625 * Trim mbufs if longer than we expect. 626 * Drop packet if shorter than we expect. 627 */ 628 if (m->m_pkthdr.len < len) { 629 IP_STATINC(IP_STAT_TOOSHORT); 630 goto bad; 631 } 632 if (m->m_pkthdr.len > len) { 633 if (m->m_len == m->m_pkthdr.len) { 634 m->m_len = len; 635 m->m_pkthdr.len = len; 636 } else 637 m_adj(m, len - m->m_pkthdr.len); 638 } 639 640 #if defined(IPSEC) 641 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 642 m->m_flags &= ~M_CANFASTFWD; 643 #else 644 /* 645 * Assume that we can create a fast-forward IP flow entry 646 * based on this packet. 647 */ 648 m->m_flags |= M_CANFASTFWD; 649 #endif 650 651 #ifdef PFIL_HOOKS 652 /* 653 * Run through list of hooks for input packets. If there are any 654 * filters which require that additional packets in the flow are 655 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 656 * Note that filters must _never_ set this flag, as another filter 657 * in the list may have previously cleared it. 658 */ 659 /* 660 * let ipfilter look at packet on the wire, 661 * not the decapsulated packet. 662 */ 663 #ifdef IPSEC 664 if (!ipsec_getnhist(m)) 665 #elif defined(FAST_IPSEC) 666 if (!ipsec_indone(m)) 667 #else 668 if (1) 669 #endif 670 { 671 struct in_addr odst; 672 673 odst = ip->ip_dst; 674 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 675 PFIL_IN) != 0) 676 return; 677 if (m == NULL) 678 return; 679 ip = mtod(m, struct ip *); 680 hlen = ip->ip_hl << 2; 681 /* 682 * XXX The setting of "srcrt" here is to prevent ip_forward() 683 * from generating ICMP redirects for packets that have 684 * been redirected by a hook back out on to the same LAN that 685 * they came from and is not an indication that the packet 686 * is being inffluenced by source routing options. This 687 * allows things like 688 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp" 689 * where tlp0 is both on the 1.1.1.0/24 network and is the 690 * default route for hosts on 1.1.1.0/24. Of course this 691 * also requires a "map tlp0 ..." to complete the story. 692 * One might argue whether or not this kind of network config. 693 * should be supported in this manner... 694 */ 695 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 696 } 697 #endif /* PFIL_HOOKS */ 698 699 #ifdef ALTQ 700 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 701 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 702 /* packet dropped by traffic conditioner */ 703 return; 704 } 705 #endif 706 707 /* 708 * Process options and, if not destined for us, 709 * ship it on. ip_dooptions returns 1 when an 710 * error was detected (causing an icmp message 711 * to be sent and the original packet to be freed). 712 */ 713 ip_nhops = 0; /* for source routed packets */ 714 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 715 return; 716 717 /* 718 * Enable a consistency check between the destination address 719 * and the arrival interface for a unicast packet (the RFC 1122 720 * strong ES model) if IP forwarding is disabled and the packet 721 * is not locally generated. 722 * 723 * XXX - Checking also should be disabled if the destination 724 * address is ipnat'ed to a different interface. 725 * 726 * XXX - Checking is incompatible with IP aliases added 727 * to the loopback interface instead of the interface where 728 * the packets are received. 729 * 730 * XXX - We need to add a per ifaddr flag for this so that 731 * we get finer grain control. 732 */ 733 checkif = ip_checkinterface && (ipforwarding == 0) && 734 (m->m_pkthdr.rcvif != NULL) && 735 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 736 737 /* 738 * Check our list of addresses, to see if the packet is for us. 739 * 740 * Traditional 4.4BSD did not consult IFF_UP at all. 741 * The behavior here is to treat addresses on !IFF_UP interface 742 * as not mine. 743 */ 744 downmatch = 0; 745 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 746 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 747 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 748 continue; 749 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 750 break; 751 else 752 downmatch++; 753 } 754 } 755 if (ia != NULL) 756 goto ours; 757 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 758 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 759 if (ifa->ifa_addr->sa_family != AF_INET) 760 continue; 761 ia = ifatoia(ifa); 762 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 763 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 764 /* 765 * Look for all-0's host part (old broadcast addr), 766 * either for subnet or net. 767 */ 768 ip->ip_dst.s_addr == ia->ia_subnet || 769 ip->ip_dst.s_addr == ia->ia_net) 770 goto ours; 771 /* 772 * An interface with IP address zero accepts 773 * all packets that arrive on that interface. 774 */ 775 if (in_nullhost(ia->ia_addr.sin_addr)) 776 goto ours; 777 } 778 } 779 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 780 struct in_multi *inm; 781 #ifdef MROUTING 782 extern struct socket *ip_mrouter; 783 784 if (ip_mrouter) { 785 /* 786 * If we are acting as a multicast router, all 787 * incoming multicast packets are passed to the 788 * kernel-level multicast forwarding function. 789 * The packet is returned (relatively) intact; if 790 * ip_mforward() returns a non-zero value, the packet 791 * must be discarded, else it may be accepted below. 792 * 793 * (The IP ident field is put in the same byte order 794 * as expected when ip_mforward() is called from 795 * ip_output().) 796 */ 797 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 798 IP_STATINC(IP_STAT_CANTFORWARD); 799 m_freem(m); 800 return; 801 } 802 803 /* 804 * The process-level routing demon needs to receive 805 * all multicast IGMP packets, whether or not this 806 * host belongs to their destination groups. 807 */ 808 if (ip->ip_p == IPPROTO_IGMP) 809 goto ours; 810 IP_STATINC(IP_STAT_CANTFORWARD); 811 } 812 #endif 813 /* 814 * See if we belong to the destination multicast group on the 815 * arrival interface. 816 */ 817 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 818 if (inm == NULL) { 819 IP_STATINC(IP_STAT_CANTFORWARD); 820 m_freem(m); 821 return; 822 } 823 goto ours; 824 } 825 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 826 in_nullhost(ip->ip_dst)) 827 goto ours; 828 829 /* 830 * Not for us; forward if possible and desirable. 831 */ 832 if (ipforwarding == 0) { 833 IP_STATINC(IP_STAT_CANTFORWARD); 834 m_freem(m); 835 } else { 836 /* 837 * If ip_dst matched any of my address on !IFF_UP interface, 838 * and there's no IFF_UP interface that matches ip_dst, 839 * send icmp unreach. Forwarding it will result in in-kernel 840 * forwarding loop till TTL goes to 0. 841 */ 842 if (downmatch) { 843 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 844 IP_STATINC(IP_STAT_CANTFORWARD); 845 return; 846 } 847 #ifdef IPSEC 848 if (ipsec4_in_reject(m, NULL)) { 849 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 850 goto bad; 851 } 852 #endif 853 #ifdef FAST_IPSEC 854 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 855 s = splsoftnet(); 856 if (mtag != NULL) { 857 tdbi = (struct tdb_ident *)(mtag + 1); 858 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 859 } else { 860 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 861 IP_FORWARDING, &error); 862 } 863 if (sp == NULL) { /* NB: can happen if error */ 864 splx(s); 865 /*XXX error stat???*/ 866 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/ 867 goto bad; 868 } 869 870 /* 871 * Check security policy against packet attributes. 872 */ 873 error = ipsec_in_reject(sp, m); 874 KEY_FREESP(&sp); 875 splx(s); 876 if (error) { 877 IP_STATINC(IP_STAT_CANTFORWARD); 878 goto bad; 879 } 880 881 /* 882 * Peek at the outbound SP for this packet to determine if 883 * it's a Fast Forward candidate. 884 */ 885 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 886 if (mtag != NULL) 887 m->m_flags &= ~M_CANFASTFWD; 888 else { 889 s = splsoftnet(); 890 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, 891 (IP_FORWARDING | 892 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 893 &error, NULL); 894 if (sp != NULL) { 895 m->m_flags &= ~M_CANFASTFWD; 896 KEY_FREESP(&sp); 897 } 898 splx(s); 899 } 900 #endif /* FAST_IPSEC */ 901 902 ip_forward(m, srcrt); 903 } 904 return; 905 906 ours: 907 /* 908 * If offset or IP_MF are set, must reassemble. 909 * Otherwise, nothing need be done. 910 * (We could look in the reassembly queue to see 911 * if the packet was previously fragmented, 912 * but it's not worth the time; just let them time out.) 913 */ 914 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 915 uint16_t off; 916 /* 917 * Prevent TCP blind data attacks by not allowing non-initial 918 * fragments to start at less than 68 bytes (minimal fragment 919 * size) and making sure the first fragment is at least 68 920 * bytes. 921 */ 922 off = (ntohs(ip->ip_off) & IP_OFFMASK) << 3; 923 if ((off > 0 ? off + hlen : len) < IP_MINFRAGSIZE - 1) { 924 IP_STATINC(IP_STAT_BADFRAGS); 925 goto bad; 926 } 927 /* 928 * Look for queue of fragments 929 * of this datagram. 930 */ 931 IPQ_LOCK(); 932 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id); 933 LIST_FOREACH(fp, &ipq[hash], ipq_q) { 934 if (ip->ip_id == fp->ipq_id && 935 in_hosteq(ip->ip_src, fp->ipq_src) && 936 in_hosteq(ip->ip_dst, fp->ipq_dst) && 937 ip->ip_p == fp->ipq_p) { 938 /* 939 * Make sure the TOS is matches previous 940 * fragments. 941 */ 942 if (ip->ip_tos != fp->ipq_tos) { 943 IP_STATINC(IP_STAT_BADFRAGS); 944 IPQ_UNLOCK(); 945 goto bad; 946 } 947 goto found; 948 } 949 } 950 fp = 0; 951 found: 952 953 /* 954 * Adjust ip_len to not reflect header, 955 * set ipqe_mff if more fragments are expected, 956 * convert offset of this to bytes. 957 */ 958 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 959 mff = (ip->ip_off & htons(IP_MF)) != 0; 960 if (mff) { 961 /* 962 * Make sure that fragments have a data length 963 * that's a non-zero multiple of 8 bytes. 964 */ 965 if (ntohs(ip->ip_len) == 0 || 966 (ntohs(ip->ip_len) & 0x7) != 0) { 967 IP_STATINC(IP_STAT_BADFRAGS); 968 IPQ_UNLOCK(); 969 goto bad; 970 } 971 } 972 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 973 974 /* 975 * If datagram marked as having more fragments 976 * or if this is not the first fragment, 977 * attempt reassembly; if it succeeds, proceed. 978 */ 979 if (mff || ip->ip_off != htons(0)) { 980 IP_STATINC(IP_STAT_FRAGMENTS); 981 s = splvm(); 982 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 983 splx(s); 984 if (ipqe == NULL) { 985 IP_STATINC(IP_STAT_RCVMEMDROP); 986 IPQ_UNLOCK(); 987 goto bad; 988 } 989 ipqe->ipqe_mff = mff; 990 ipqe->ipqe_m = m; 991 ipqe->ipqe_ip = ip; 992 m = ip_reass(ipqe, fp, &ipq[hash]); 993 if (m == 0) { 994 IPQ_UNLOCK(); 995 return; 996 } 997 IP_STATINC(IP_STAT_REASSEMBLED); 998 ip = mtod(m, struct ip *); 999 hlen = ip->ip_hl << 2; 1000 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 1001 } else 1002 if (fp) 1003 ip_freef(fp); 1004 IPQ_UNLOCK(); 1005 } 1006 1007 #if defined(IPSEC) 1008 /* 1009 * enforce IPsec policy checking if we are seeing last header. 1010 * note that we do not visit this with protocols with pcb layer 1011 * code - like udp/tcp/raw ip. 1012 */ 1013 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 1014 ipsec4_in_reject(m, NULL)) { 1015 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1016 goto bad; 1017 } 1018 #endif 1019 #ifdef FAST_IPSEC 1020 /* 1021 * enforce IPsec policy checking if we are seeing last header. 1022 * note that we do not visit this with protocols with pcb layer 1023 * code - like udp/tcp/raw ip. 1024 */ 1025 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 1026 /* 1027 * Check if the packet has already had IPsec processing 1028 * done. If so, then just pass it along. This tag gets 1029 * set during AH, ESP, etc. input handling, before the 1030 * packet is returned to the ip input queue for delivery. 1031 */ 1032 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 1033 s = splsoftnet(); 1034 if (mtag != NULL) { 1035 tdbi = (struct tdb_ident *)(mtag + 1); 1036 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 1037 } else { 1038 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1039 IP_FORWARDING, &error); 1040 } 1041 if (sp != NULL) { 1042 /* 1043 * Check security policy against packet attributes. 1044 */ 1045 error = ipsec_in_reject(sp, m); 1046 KEY_FREESP(&sp); 1047 } else { 1048 /* XXX error stat??? */ 1049 error = EINVAL; 1050 DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 1051 } 1052 splx(s); 1053 if (error) 1054 goto bad; 1055 } 1056 #endif /* FAST_IPSEC */ 1057 1058 /* 1059 * Switch out to protocol's input routine. 1060 */ 1061 #if IFA_STATS 1062 if (ia && ip) 1063 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 1064 #endif 1065 IP_STATINC(IP_STAT_DELIVERED); 1066 { 1067 int off = hlen, nh = ip->ip_p; 1068 1069 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 1070 return; 1071 } 1072 bad: 1073 m_freem(m); 1074 return; 1075 1076 badcsum: 1077 IP_STATINC(IP_STAT_BADSUM); 1078 m_freem(m); 1079 } 1080 1081 /* 1082 * Take incoming datagram fragment and try to 1083 * reassemble it into whole datagram. If a chain for 1084 * reassembly of this datagram already exists, then it 1085 * is given as fp; otherwise have to make a chain. 1086 */ 1087 struct mbuf * 1088 ip_reass(struct ipqent *ipqe, struct ipq *fp, struct ipqhead *ipqhead) 1089 { 1090 struct mbuf *m = ipqe->ipqe_m; 1091 struct ipqent *nq, *p, *q; 1092 struct ip *ip; 1093 struct mbuf *t; 1094 int hlen = ipqe->ipqe_ip->ip_hl << 2; 1095 int i, next, s; 1096 1097 IPQ_LOCK_CHECK(); 1098 1099 /* 1100 * Presence of header sizes in mbufs 1101 * would confuse code below. 1102 */ 1103 m->m_data += hlen; 1104 m->m_len -= hlen; 1105 1106 #ifdef notyet 1107 /* make sure fragment limit is up-to-date */ 1108 CHECK_NMBCLUSTER_PARAMS(); 1109 1110 /* If we have too many fragments, drop the older half. */ 1111 if (ip_nfrags >= ip_maxfrags) 1112 ip_reass_drophalf(void); 1113 #endif 1114 1115 /* 1116 * We are about to add a fragment; increment frag count. 1117 */ 1118 ip_nfrags++; 1119 1120 /* 1121 * If first fragment to arrive, create a reassembly queue. 1122 */ 1123 if (fp == 0) { 1124 /* 1125 * Enforce upper bound on number of fragmented packets 1126 * for which we attempt reassembly; 1127 * If maxfrag is 0, never accept fragments. 1128 * If maxfrag is -1, accept all fragments without limitation. 1129 */ 1130 if (ip_maxfragpackets < 0) 1131 ; 1132 else if (ip_nfragpackets >= ip_maxfragpackets) 1133 goto dropfrag; 1134 ip_nfragpackets++; 1135 fp = malloc(sizeof (struct ipq), M_FTABLE, M_NOWAIT); 1136 if (fp == NULL) 1137 goto dropfrag; 1138 LIST_INSERT_HEAD(ipqhead, fp, ipq_q); 1139 fp->ipq_nfrags = 1; 1140 fp->ipq_ttl = IPFRAGTTL; 1141 fp->ipq_p = ipqe->ipqe_ip->ip_p; 1142 fp->ipq_id = ipqe->ipqe_ip->ip_id; 1143 fp->ipq_tos = ipqe->ipqe_ip->ip_tos; 1144 TAILQ_INIT(&fp->ipq_fragq); 1145 fp->ipq_src = ipqe->ipqe_ip->ip_src; 1146 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 1147 p = NULL; 1148 goto insert; 1149 } else { 1150 fp->ipq_nfrags++; 1151 } 1152 1153 /* 1154 * Find a segment which begins after this one does. 1155 */ 1156 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1157 p = q, q = TAILQ_NEXT(q, ipqe_q)) 1158 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 1159 break; 1160 1161 /* 1162 * If there is a preceding segment, it may provide some of 1163 * our data already. If so, drop the data from the incoming 1164 * segment. If it provides all of our data, drop us. 1165 */ 1166 if (p != NULL) { 1167 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 1168 ntohs(ipqe->ipqe_ip->ip_off); 1169 if (i > 0) { 1170 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 1171 goto dropfrag; 1172 m_adj(ipqe->ipqe_m, i); 1173 ipqe->ipqe_ip->ip_off = 1174 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 1175 ipqe->ipqe_ip->ip_len = 1176 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 1177 } 1178 } 1179 1180 /* 1181 * While we overlap succeeding segments trim them or, 1182 * if they are completely covered, dequeue them. 1183 */ 1184 for (; q != NULL && 1185 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 1186 ntohs(q->ipqe_ip->ip_off); q = nq) { 1187 i = (ntohs(ipqe->ipqe_ip->ip_off) + 1188 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 1189 if (i < ntohs(q->ipqe_ip->ip_len)) { 1190 q->ipqe_ip->ip_len = 1191 htons(ntohs(q->ipqe_ip->ip_len) - i); 1192 q->ipqe_ip->ip_off = 1193 htons(ntohs(q->ipqe_ip->ip_off) + i); 1194 m_adj(q->ipqe_m, i); 1195 break; 1196 } 1197 nq = TAILQ_NEXT(q, ipqe_q); 1198 m_freem(q->ipqe_m); 1199 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1200 s = splvm(); 1201 pool_put(&ipqent_pool, q); 1202 splx(s); 1203 fp->ipq_nfrags--; 1204 ip_nfrags--; 1205 } 1206 1207 insert: 1208 /* 1209 * Stick new segment in its place; 1210 * check for complete reassembly. 1211 */ 1212 if (p == NULL) { 1213 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1214 } else { 1215 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1216 } 1217 next = 0; 1218 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1219 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1220 if (ntohs(q->ipqe_ip->ip_off) != next) 1221 return (0); 1222 next += ntohs(q->ipqe_ip->ip_len); 1223 } 1224 if (p->ipqe_mff) 1225 return (0); 1226 1227 /* 1228 * Reassembly is complete. Check for a bogus message size and 1229 * concatenate fragments. 1230 */ 1231 q = TAILQ_FIRST(&fp->ipq_fragq); 1232 ip = q->ipqe_ip; 1233 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1234 IP_STATINC(IP_STAT_TOOLONG); 1235 ip_freef(fp); 1236 return (0); 1237 } 1238 m = q->ipqe_m; 1239 t = m->m_next; 1240 m->m_next = 0; 1241 m_cat(m, t); 1242 nq = TAILQ_NEXT(q, ipqe_q); 1243 s = splvm(); 1244 pool_put(&ipqent_pool, q); 1245 splx(s); 1246 for (q = nq; q != NULL; q = nq) { 1247 t = q->ipqe_m; 1248 nq = TAILQ_NEXT(q, ipqe_q); 1249 s = splvm(); 1250 pool_put(&ipqent_pool, q); 1251 splx(s); 1252 m_cat(m, t); 1253 } 1254 ip_nfrags -= fp->ipq_nfrags; 1255 1256 /* 1257 * Create header for new ip packet by 1258 * modifying header of first packet; 1259 * dequeue and discard fragment reassembly header. 1260 * Make header visible. 1261 */ 1262 ip->ip_len = htons(next); 1263 ip->ip_src = fp->ipq_src; 1264 ip->ip_dst = fp->ipq_dst; 1265 LIST_REMOVE(fp, ipq_q); 1266 free(fp, M_FTABLE); 1267 ip_nfragpackets--; 1268 m->m_len += (ip->ip_hl << 2); 1269 m->m_data -= (ip->ip_hl << 2); 1270 /* some debugging cruft by sklower, below, will go away soon */ 1271 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1272 int plen = 0; 1273 for (t = m; t; t = t->m_next) 1274 plen += t->m_len; 1275 m->m_pkthdr.len = plen; 1276 m->m_pkthdr.csum_flags = 0; 1277 } 1278 return (m); 1279 1280 dropfrag: 1281 if (fp != 0) 1282 fp->ipq_nfrags--; 1283 ip_nfrags--; 1284 IP_STATINC(IP_STAT_FRAGDROPPED); 1285 m_freem(m); 1286 s = splvm(); 1287 pool_put(&ipqent_pool, ipqe); 1288 splx(s); 1289 return (0); 1290 } 1291 1292 /* 1293 * Free a fragment reassembly header and all 1294 * associated datagrams. 1295 */ 1296 void 1297 ip_freef(struct ipq *fp) 1298 { 1299 struct ipqent *q, *p; 1300 u_int nfrags = 0; 1301 int s; 1302 1303 IPQ_LOCK_CHECK(); 1304 1305 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1306 p = TAILQ_NEXT(q, ipqe_q); 1307 m_freem(q->ipqe_m); 1308 nfrags++; 1309 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1310 s = splvm(); 1311 pool_put(&ipqent_pool, q); 1312 splx(s); 1313 } 1314 1315 if (nfrags != fp->ipq_nfrags) 1316 printf("ip_freef: nfrags %d != %d\n", fp->ipq_nfrags, nfrags); 1317 ip_nfrags -= nfrags; 1318 LIST_REMOVE(fp, ipq_q); 1319 free(fp, M_FTABLE); 1320 ip_nfragpackets--; 1321 } 1322 1323 /* 1324 * IP reassembly TTL machinery for multiplicative drop. 1325 */ 1326 static u_int fragttl_histo[(IPFRAGTTL+1)]; 1327 1328 1329 /* 1330 * Decrement TTL of all reasembly queue entries by `ticks'. 1331 * Count number of distinct fragments (as opposed to partial, fragmented 1332 * datagrams) in the reassembly queue. While we traverse the entire 1333 * reassembly queue, compute and return the median TTL over all fragments. 1334 */ 1335 static u_int 1336 ip_reass_ttl_decr(u_int ticks) 1337 { 1338 u_int nfrags, median, dropfraction, keepfraction; 1339 struct ipq *fp, *nfp; 1340 int i; 1341 1342 nfrags = 0; 1343 memset(fragttl_histo, 0, sizeof fragttl_histo); 1344 1345 for (i = 0; i < IPREASS_NHASH; i++) { 1346 for (fp = LIST_FIRST(&ipq[i]); fp != NULL; fp = nfp) { 1347 fp->ipq_ttl = ((fp->ipq_ttl <= ticks) ? 1348 0 : fp->ipq_ttl - ticks); 1349 nfp = LIST_NEXT(fp, ipq_q); 1350 if (fp->ipq_ttl == 0) { 1351 IP_STATINC(IP_STAT_FRAGTIMEOUT); 1352 ip_freef(fp); 1353 } else { 1354 nfrags += fp->ipq_nfrags; 1355 fragttl_histo[fp->ipq_ttl] += fp->ipq_nfrags; 1356 } 1357 } 1358 } 1359 1360 KASSERT(ip_nfrags == nfrags); 1361 1362 /* Find median (or other drop fraction) in histogram. */ 1363 dropfraction = (ip_nfrags / 2); 1364 keepfraction = ip_nfrags - dropfraction; 1365 for (i = IPFRAGTTL, median = 0; i >= 0; i--) { 1366 median += fragttl_histo[i]; 1367 if (median >= keepfraction) 1368 break; 1369 } 1370 1371 /* Return TTL of median (or other fraction). */ 1372 return (u_int)i; 1373 } 1374 1375 void 1376 ip_reass_drophalf(void) 1377 { 1378 1379 u_int median_ticks; 1380 /* 1381 * Compute median TTL of all fragments, and count frags 1382 * with that TTL or lower (roughly half of all fragments). 1383 */ 1384 median_ticks = ip_reass_ttl_decr(0); 1385 1386 /* Drop half. */ 1387 median_ticks = ip_reass_ttl_decr(median_ticks); 1388 1389 } 1390 1391 /* 1392 * IP timer processing; 1393 * if a timer expires on a reassembly 1394 * queue, discard it. 1395 */ 1396 void 1397 ip_slowtimo(void) 1398 { 1399 static u_int dropscanidx = 0; 1400 u_int i; 1401 u_int median_ttl; 1402 1403 mutex_enter(softnet_lock); 1404 KERNEL_LOCK(1, NULL); 1405 1406 IPQ_LOCK(); 1407 1408 /* Age TTL of all fragments by 1 tick .*/ 1409 median_ttl = ip_reass_ttl_decr(1); 1410 1411 /* make sure fragment limit is up-to-date */ 1412 CHECK_NMBCLUSTER_PARAMS(); 1413 1414 /* If we have too many fragments, drop the older half. */ 1415 if (ip_nfrags > ip_maxfrags) 1416 ip_reass_ttl_decr(median_ttl); 1417 1418 /* 1419 * If we are over the maximum number of fragmented packets 1420 * (due to the limit being lowered), drain off 1421 * enough to get down to the new limit. Start draining 1422 * from the reassembly hashqueue most recently drained. 1423 */ 1424 if (ip_maxfragpackets < 0) 1425 ; 1426 else { 1427 int wrapped = 0; 1428 1429 i = dropscanidx; 1430 while (ip_nfragpackets > ip_maxfragpackets && wrapped == 0) { 1431 while (LIST_FIRST(&ipq[i]) != NULL) 1432 ip_freef(LIST_FIRST(&ipq[i])); 1433 if (++i >= IPREASS_NHASH) { 1434 i = 0; 1435 } 1436 /* 1437 * Dont scan forever even if fragment counters are 1438 * wrong: stop after scanning entire reassembly queue. 1439 */ 1440 if (i == dropscanidx) 1441 wrapped = 1; 1442 } 1443 dropscanidx = i; 1444 } 1445 IPQ_UNLOCK(); 1446 1447 KERNEL_UNLOCK_ONE(NULL); 1448 mutex_exit(softnet_lock); 1449 } 1450 1451 /* 1452 * Drain off all datagram fragments. Don't acquire softnet_lock as 1453 * can be called from hardware interrupt context. 1454 */ 1455 void 1456 ip_drain(void) 1457 { 1458 1459 KERNEL_LOCK(1, NULL); 1460 1461 /* 1462 * We may be called from a device's interrupt context. If 1463 * the ipq is already busy, just bail out now. 1464 */ 1465 if (ipq_lock_try() != 0) { 1466 /* 1467 * Drop half the total fragments now. If more mbufs are 1468 * needed, we will be called again soon. 1469 */ 1470 ip_reass_drophalf(); 1471 IPQ_UNLOCK(); 1472 } 1473 1474 KERNEL_UNLOCK_ONE(NULL); 1475 } 1476 1477 /* 1478 * Do option processing on a datagram, 1479 * possibly discarding it if bad options are encountered, 1480 * or forwarding it if source-routed. 1481 * Returns 1 if packet has been forwarded/freed, 1482 * 0 if the packet should be processed further. 1483 */ 1484 int 1485 ip_dooptions(struct mbuf *m) 1486 { 1487 struct ip *ip = mtod(m, struct ip *); 1488 u_char *cp, *cp0; 1489 struct ip_timestamp *ipt; 1490 struct in_ifaddr *ia; 1491 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1492 struct in_addr dst; 1493 n_time ntime; 1494 1495 dst = ip->ip_dst; 1496 cp = (u_char *)(ip + 1); 1497 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1498 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1499 opt = cp[IPOPT_OPTVAL]; 1500 if (opt == IPOPT_EOL) 1501 break; 1502 if (opt == IPOPT_NOP) 1503 optlen = 1; 1504 else { 1505 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1506 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1507 goto bad; 1508 } 1509 optlen = cp[IPOPT_OLEN]; 1510 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1511 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1512 goto bad; 1513 } 1514 } 1515 switch (opt) { 1516 1517 default: 1518 break; 1519 1520 /* 1521 * Source routing with record. 1522 * Find interface with current destination address. 1523 * If none on this machine then drop if strictly routed, 1524 * or do nothing if loosely routed. 1525 * Record interface address and bring up next address 1526 * component. If strictly routed make sure next 1527 * address is on directly accessible net. 1528 */ 1529 case IPOPT_LSRR: 1530 case IPOPT_SSRR: 1531 if (ip_allowsrcrt == 0) { 1532 type = ICMP_UNREACH; 1533 code = ICMP_UNREACH_NET_PROHIB; 1534 goto bad; 1535 } 1536 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1537 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1538 goto bad; 1539 } 1540 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1541 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1542 goto bad; 1543 } 1544 ipaddr.sin_addr = ip->ip_dst; 1545 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1546 if (ia == 0) { 1547 if (opt == IPOPT_SSRR) { 1548 type = ICMP_UNREACH; 1549 code = ICMP_UNREACH_SRCFAIL; 1550 goto bad; 1551 } 1552 /* 1553 * Loose routing, and not at next destination 1554 * yet; nothing to do except forward. 1555 */ 1556 break; 1557 } 1558 off--; /* 0 origin */ 1559 if ((off + sizeof(struct in_addr)) > optlen) { 1560 /* 1561 * End of source route. Should be for us. 1562 */ 1563 save_rte(cp, ip->ip_src); 1564 break; 1565 } 1566 /* 1567 * locate outgoing interface 1568 */ 1569 memcpy((void *)&ipaddr.sin_addr, (void *)(cp + off), 1570 sizeof(ipaddr.sin_addr)); 1571 if (opt == IPOPT_SSRR) 1572 ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr))); 1573 else 1574 ia = ip_rtaddr(ipaddr.sin_addr); 1575 if (ia == 0) { 1576 type = ICMP_UNREACH; 1577 code = ICMP_UNREACH_SRCFAIL; 1578 goto bad; 1579 } 1580 ip->ip_dst = ipaddr.sin_addr; 1581 bcopy((void *)&ia->ia_addr.sin_addr, 1582 (void *)(cp + off), sizeof(struct in_addr)); 1583 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1584 /* 1585 * Let ip_intr's mcast routing check handle mcast pkts 1586 */ 1587 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1588 break; 1589 1590 case IPOPT_RR: 1591 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1592 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1593 goto bad; 1594 } 1595 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1596 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1597 goto bad; 1598 } 1599 /* 1600 * If no space remains, ignore. 1601 */ 1602 off--; /* 0 origin */ 1603 if ((off + sizeof(struct in_addr)) > optlen) 1604 break; 1605 memcpy((void *)&ipaddr.sin_addr, (void *)(&ip->ip_dst), 1606 sizeof(ipaddr.sin_addr)); 1607 /* 1608 * locate outgoing interface; if we're the destination, 1609 * use the incoming interface (should be same). 1610 */ 1611 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1612 == NULL && 1613 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1614 type = ICMP_UNREACH; 1615 code = ICMP_UNREACH_HOST; 1616 goto bad; 1617 } 1618 bcopy((void *)&ia->ia_addr.sin_addr, 1619 (void *)(cp + off), sizeof(struct in_addr)); 1620 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1621 break; 1622 1623 case IPOPT_TS: 1624 code = cp - (u_char *)ip; 1625 ipt = (struct ip_timestamp *)cp; 1626 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1627 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1628 goto bad; 1629 } 1630 if (ipt->ipt_ptr < 5) { 1631 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1632 goto bad; 1633 } 1634 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1635 if (++ipt->ipt_oflw == 0) { 1636 code = (u_char *)&ipt->ipt_ptr - 1637 (u_char *)ip; 1638 goto bad; 1639 } 1640 break; 1641 } 1642 cp0 = (cp + ipt->ipt_ptr - 1); 1643 switch (ipt->ipt_flg) { 1644 1645 case IPOPT_TS_TSONLY: 1646 break; 1647 1648 case IPOPT_TS_TSANDADDR: 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 ipaddr.sin_addr = dst; 1656 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1657 m->m_pkthdr.rcvif)); 1658 if (ia == 0) 1659 continue; 1660 bcopy(&ia->ia_addr.sin_addr, 1661 cp0, sizeof(struct in_addr)); 1662 ipt->ipt_ptr += sizeof(struct in_addr); 1663 break; 1664 1665 case IPOPT_TS_PRESPEC: 1666 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1667 sizeof(struct in_addr) > ipt->ipt_len) { 1668 code = (u_char *)&ipt->ipt_ptr - 1669 (u_char *)ip; 1670 goto bad; 1671 } 1672 memcpy(&ipaddr.sin_addr, cp0, 1673 sizeof(struct in_addr)); 1674 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1675 == NULL) 1676 continue; 1677 ipt->ipt_ptr += sizeof(struct in_addr); 1678 break; 1679 1680 default: 1681 /* XXX can't take &ipt->ipt_flg */ 1682 code = (u_char *)&ipt->ipt_ptr - 1683 (u_char *)ip + 1; 1684 goto bad; 1685 } 1686 ntime = iptime(); 1687 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1688 memmove((char *)cp + ipt->ipt_ptr - 1, cp0, 1689 sizeof(n_time)); 1690 ipt->ipt_ptr += sizeof(n_time); 1691 } 1692 } 1693 if (forward) { 1694 if (ip_forwsrcrt == 0) { 1695 type = ICMP_UNREACH; 1696 code = ICMP_UNREACH_SRCFAIL; 1697 goto bad; 1698 } 1699 ip_forward(m, 1); 1700 return (1); 1701 } 1702 return (0); 1703 bad: 1704 icmp_error(m, type, code, 0, 0); 1705 IP_STATINC(IP_STAT_BADOPTIONS); 1706 return (1); 1707 } 1708 1709 /* 1710 * Given address of next destination (final or next hop), 1711 * return internet address info of interface to be used to get there. 1712 */ 1713 struct in_ifaddr * 1714 ip_rtaddr(struct in_addr dst) 1715 { 1716 struct rtentry *rt; 1717 union { 1718 struct sockaddr dst; 1719 struct sockaddr_in dst4; 1720 } u; 1721 1722 sockaddr_in_init(&u.dst4, &dst, 0); 1723 1724 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) 1725 return NULL; 1726 1727 return ifatoia(rt->rt_ifa); 1728 } 1729 1730 /* 1731 * Save incoming source route for use in replies, 1732 * to be picked up later by ip_srcroute if the receiver is interested. 1733 */ 1734 void 1735 save_rte(u_char *option, struct in_addr dst) 1736 { 1737 unsigned olen; 1738 1739 olen = option[IPOPT_OLEN]; 1740 #ifdef DIAGNOSTIC 1741 if (ipprintfs) 1742 printf("save_rte: olen %d\n", olen); 1743 #endif /* 0 */ 1744 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1745 return; 1746 memcpy((void *)ip_srcrt.srcopt, (void *)option, olen); 1747 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1748 ip_srcrt.dst = dst; 1749 } 1750 1751 /* 1752 * Retrieve incoming source route for use in replies, 1753 * in the same form used by setsockopt. 1754 * The first hop is placed before the options, will be removed later. 1755 */ 1756 struct mbuf * 1757 ip_srcroute(void) 1758 { 1759 struct in_addr *p, *q; 1760 struct mbuf *m; 1761 1762 if (ip_nhops == 0) 1763 return NULL; 1764 m = m_get(M_DONTWAIT, MT_SOOPTS); 1765 if (m == 0) 1766 return NULL; 1767 1768 MCLAIM(m, &inetdomain.dom_mowner); 1769 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1770 1771 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1772 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1773 OPTSIZ; 1774 #ifdef DIAGNOSTIC 1775 if (ipprintfs) 1776 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1777 #endif 1778 1779 /* 1780 * First save first hop for return route 1781 */ 1782 p = &ip_srcrt.route[ip_nhops - 1]; 1783 *(mtod(m, struct in_addr *)) = *p--; 1784 #ifdef DIAGNOSTIC 1785 if (ipprintfs) 1786 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1787 #endif 1788 1789 /* 1790 * Copy option fields and padding (nop) to mbuf. 1791 */ 1792 ip_srcrt.nop = IPOPT_NOP; 1793 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1794 memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop, 1795 OPTSIZ); 1796 q = (struct in_addr *)(mtod(m, char *) + 1797 sizeof(struct in_addr) + OPTSIZ); 1798 #undef OPTSIZ 1799 /* 1800 * Record return path as an IP source route, 1801 * reversing the path (pointers are now aligned). 1802 */ 1803 while (p >= ip_srcrt.route) { 1804 #ifdef DIAGNOSTIC 1805 if (ipprintfs) 1806 printf(" %x", ntohl(q->s_addr)); 1807 #endif 1808 *q++ = *p--; 1809 } 1810 /* 1811 * Last hop goes to final destination. 1812 */ 1813 *q = ip_srcrt.dst; 1814 #ifdef DIAGNOSTIC 1815 if (ipprintfs) 1816 printf(" %x\n", ntohl(q->s_addr)); 1817 #endif 1818 return (m); 1819 } 1820 1821 const int inetctlerrmap[PRC_NCMDS] = { 1822 [PRC_MSGSIZE] = EMSGSIZE, 1823 [PRC_HOSTDEAD] = EHOSTDOWN, 1824 [PRC_HOSTUNREACH] = EHOSTUNREACH, 1825 [PRC_UNREACH_NET] = EHOSTUNREACH, 1826 [PRC_UNREACH_HOST] = EHOSTUNREACH, 1827 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED, 1828 [PRC_UNREACH_PORT] = ECONNREFUSED, 1829 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH, 1830 [PRC_PARAMPROB] = ENOPROTOOPT, 1831 }; 1832 1833 /* 1834 * Forward a packet. If some error occurs return the sender 1835 * an icmp packet. Note we can't always generate a meaningful 1836 * icmp message because icmp doesn't have a large enough repertoire 1837 * of codes and types. 1838 * 1839 * If not forwarding, just drop the packet. This could be confusing 1840 * if ipforwarding was zero but some routing protocol was advancing 1841 * us as a gateway to somewhere. However, we must let the routing 1842 * protocol deal with that. 1843 * 1844 * The srcrt parameter indicates whether the packet is being forwarded 1845 * via a source route. 1846 */ 1847 void 1848 ip_forward(struct mbuf *m, int srcrt) 1849 { 1850 struct ip *ip = mtod(m, struct ip *); 1851 struct rtentry *rt; 1852 int error, type = 0, code = 0, destmtu = 0; 1853 struct mbuf *mcopy; 1854 n_long dest; 1855 union { 1856 struct sockaddr dst; 1857 struct sockaddr_in dst4; 1858 } u; 1859 1860 /* 1861 * We are now in the output path. 1862 */ 1863 MCLAIM(m, &ip_tx_mowner); 1864 1865 /* 1866 * Clear any in-bound checksum flags for this packet. 1867 */ 1868 m->m_pkthdr.csum_flags = 0; 1869 1870 dest = 0; 1871 #ifdef DIAGNOSTIC 1872 if (ipprintfs) { 1873 printf("forward: src %s ", inet_ntoa(ip->ip_src)); 1874 printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl); 1875 } 1876 #endif 1877 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1878 IP_STATINC(IP_STAT_CANTFORWARD); 1879 m_freem(m); 1880 return; 1881 } 1882 if (ip->ip_ttl <= IPTTLDEC) { 1883 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1884 return; 1885 } 1886 1887 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0); 1888 if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) { 1889 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0); 1890 return; 1891 } 1892 1893 /* 1894 * Save at most 68 bytes of the packet in case 1895 * we need to generate an ICMP message to the src. 1896 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1897 */ 1898 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1899 if (mcopy) 1900 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1901 1902 ip->ip_ttl -= IPTTLDEC; 1903 1904 /* 1905 * If forwarding packet using same interface that it came in on, 1906 * perhaps should send a redirect to sender to shortcut a hop. 1907 * Only send redirect if source is sending directly to us, 1908 * and if packet was not source routed (or has any options). 1909 * Also, don't send redirect if forwarding using a default route 1910 * or a route modified by a redirect. 1911 */ 1912 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1913 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1914 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) && 1915 ipsendredirects && !srcrt) { 1916 if (rt->rt_ifa && 1917 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1918 ifatoia(rt->rt_ifa)->ia_subnet) { 1919 if (rt->rt_flags & RTF_GATEWAY) 1920 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1921 else 1922 dest = ip->ip_dst.s_addr; 1923 /* 1924 * Router requirements says to only send host 1925 * redirects. 1926 */ 1927 type = ICMP_REDIRECT; 1928 code = ICMP_REDIRECT_HOST; 1929 #ifdef DIAGNOSTIC 1930 if (ipprintfs) 1931 printf("redirect (%d) to %x\n", code, 1932 (u_int32_t)dest); 1933 #endif 1934 } 1935 } 1936 1937 error = ip_output(m, NULL, &ipforward_rt, 1938 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1939 (struct ip_moptions *)NULL, (struct socket *)NULL); 1940 1941 if (error) 1942 IP_STATINC(IP_STAT_CANTFORWARD); 1943 else { 1944 uint64_t *ips = IP_STAT_GETREF(); 1945 ips[IP_STAT_FORWARD]++; 1946 if (type) { 1947 ips[IP_STAT_REDIRECTSENT]++; 1948 IP_STAT_PUTREF(); 1949 } else { 1950 IP_STAT_PUTREF(); 1951 if (mcopy) { 1952 #ifdef GATEWAY 1953 if (mcopy->m_flags & M_CANFASTFWD) 1954 ipflow_create(&ipforward_rt, mcopy); 1955 #endif 1956 m_freem(mcopy); 1957 } 1958 return; 1959 } 1960 } 1961 if (mcopy == NULL) 1962 return; 1963 1964 switch (error) { 1965 1966 case 0: /* forwarded, but need redirect */ 1967 /* type, code set above */ 1968 break; 1969 1970 case ENETUNREACH: /* shouldn't happen, checked above */ 1971 case EHOSTUNREACH: 1972 case ENETDOWN: 1973 case EHOSTDOWN: 1974 default: 1975 type = ICMP_UNREACH; 1976 code = ICMP_UNREACH_HOST; 1977 break; 1978 1979 case EMSGSIZE: 1980 type = ICMP_UNREACH; 1981 code = ICMP_UNREACH_NEEDFRAG; 1982 1983 if ((rt = rtcache_validate(&ipforward_rt)) != NULL) 1984 destmtu = rt->rt_ifp->if_mtu; 1985 1986 #if defined(IPSEC) || defined(FAST_IPSEC) 1987 { 1988 /* 1989 * If the packet is routed over IPsec tunnel, tell the 1990 * originator the tunnel MTU. 1991 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1992 * XXX quickhack!!! 1993 */ 1994 1995 struct secpolicy *sp; 1996 int ipsecerror; 1997 size_t ipsechdr; 1998 struct route *ro; 1999 2000 sp = ipsec4_getpolicybyaddr(mcopy, 2001 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 2002 &ipsecerror); 2003 2004 if (sp != NULL) { 2005 /* count IPsec header size */ 2006 ipsechdr = ipsec4_hdrsiz(mcopy, 2007 IPSEC_DIR_OUTBOUND, NULL); 2008 2009 /* 2010 * find the correct route for outer IPv4 2011 * header, compute tunnel MTU. 2012 */ 2013 2014 if (sp->req != NULL 2015 && sp->req->sav != NULL 2016 && sp->req->sav->sah != NULL) { 2017 ro = &sp->req->sav->sah->sa_route; 2018 rt = rtcache_validate(ro); 2019 if (rt && rt->rt_ifp) { 2020 destmtu = 2021 rt->rt_rmx.rmx_mtu ? 2022 rt->rt_rmx.rmx_mtu : 2023 rt->rt_ifp->if_mtu; 2024 destmtu -= ipsechdr; 2025 } 2026 } 2027 2028 #ifdef IPSEC 2029 key_freesp(sp); 2030 #else 2031 KEY_FREESP(&sp); 2032 #endif 2033 } 2034 } 2035 #endif /*defined(IPSEC) || defined(FAST_IPSEC)*/ 2036 IP_STATINC(IP_STAT_CANTFRAG); 2037 break; 2038 2039 case ENOBUFS: 2040 #if 1 2041 /* 2042 * a router should not generate ICMP_SOURCEQUENCH as 2043 * required in RFC1812 Requirements for IP Version 4 Routers. 2044 * source quench could be a big problem under DoS attacks, 2045 * or if the underlying interface is rate-limited. 2046 */ 2047 if (mcopy) 2048 m_freem(mcopy); 2049 return; 2050 #else 2051 type = ICMP_SOURCEQUENCH; 2052 code = 0; 2053 break; 2054 #endif 2055 } 2056 icmp_error(mcopy, type, code, dest, destmtu); 2057 } 2058 2059 void 2060 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 2061 struct mbuf *m) 2062 { 2063 2064 if (inp->inp_socket->so_options & SO_TIMESTAMP 2065 #ifdef SO_OTIMESTAMP 2066 || inp->inp_socket->so_options & SO_OTIMESTAMP 2067 #endif 2068 ) { 2069 struct timeval tv; 2070 2071 microtime(&tv); 2072 #ifdef SO_OTIMESTAMP 2073 if (inp->inp_socket->so_options & SO_OTIMESTAMP) { 2074 struct timeval50 tv50; 2075 timeval_to_timeval50(&tv, &tv50); 2076 *mp = sbcreatecontrol((void *) &tv50, sizeof(tv50), 2077 SCM_OTIMESTAMP, SOL_SOCKET); 2078 } else 2079 #endif 2080 *mp = sbcreatecontrol((void *) &tv, sizeof(tv), 2081 SCM_TIMESTAMP, SOL_SOCKET); 2082 if (*mp) 2083 mp = &(*mp)->m_next; 2084 } 2085 if (inp->inp_flags & INP_RECVDSTADDR) { 2086 *mp = sbcreatecontrol((void *) &ip->ip_dst, 2087 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 2088 if (*mp) 2089 mp = &(*mp)->m_next; 2090 } 2091 #ifdef notyet 2092 /* 2093 * XXX 2094 * Moving these out of udp_input() made them even more broken 2095 * than they already were. 2096 * - fenner@parc.xerox.com 2097 */ 2098 /* options were tossed already */ 2099 if (inp->inp_flags & INP_RECVOPTS) { 2100 *mp = sbcreatecontrol((void *) opts_deleted_above, 2101 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 2102 if (*mp) 2103 mp = &(*mp)->m_next; 2104 } 2105 /* ip_srcroute doesn't do what we want here, need to fix */ 2106 if (inp->inp_flags & INP_RECVRETOPTS) { 2107 *mp = sbcreatecontrol((void *) ip_srcroute(), 2108 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 2109 if (*mp) 2110 mp = &(*mp)->m_next; 2111 } 2112 #endif 2113 if (inp->inp_flags & INP_RECVIF) { 2114 struct sockaddr_dl sdl; 2115 2116 sockaddr_dl_init(&sdl, sizeof(sdl), 2117 (m->m_pkthdr.rcvif != NULL) 2118 ? m->m_pkthdr.rcvif->if_index 2119 : 0, 2120 0, NULL, 0, NULL, 0); 2121 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP); 2122 if (*mp) 2123 mp = &(*mp)->m_next; 2124 } 2125 if (inp->inp_flags & INP_RECVTTL) { 2126 *mp = sbcreatecontrol((void *) &ip->ip_ttl, 2127 sizeof(uint8_t), IP_RECVTTL, IPPROTO_IP); 2128 if (*mp) 2129 mp = &(*mp)->m_next; 2130 } 2131 } 2132 2133 /* 2134 * sysctl helper routine for net.inet.ip.forwsrcrt. 2135 */ 2136 static int 2137 sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS) 2138 { 2139 int error, tmp; 2140 struct sysctlnode node; 2141 2142 node = *rnode; 2143 tmp = ip_forwsrcrt; 2144 node.sysctl_data = &tmp; 2145 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2146 if (error || newp == NULL) 2147 return (error); 2148 2149 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT, 2150 0, NULL, NULL, NULL); 2151 if (error) 2152 return (error); 2153 2154 ip_forwsrcrt = tmp; 2155 2156 return (0); 2157 } 2158 2159 /* 2160 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the 2161 * range of the new value and tweaks timers if it changes. 2162 */ 2163 static int 2164 sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS) 2165 { 2166 int error, tmp; 2167 struct sysctlnode node; 2168 2169 node = *rnode; 2170 tmp = ip_mtudisc_timeout; 2171 node.sysctl_data = &tmp; 2172 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2173 if (error || newp == NULL) 2174 return (error); 2175 if (tmp < 0) 2176 return (EINVAL); 2177 2178 mutex_enter(softnet_lock); 2179 2180 ip_mtudisc_timeout = tmp; 2181 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout); 2182 2183 mutex_exit(softnet_lock); 2184 2185 return (0); 2186 } 2187 2188 #ifdef GATEWAY 2189 /* 2190 * sysctl helper routine for net.inet.ip.maxflows. 2191 */ 2192 static int 2193 sysctl_net_inet_ip_maxflows(SYSCTLFN_ARGS) 2194 { 2195 int error; 2196 2197 error = sysctl_lookup(SYSCTLFN_CALL(rnode)); 2198 if (error || newp == NULL) 2199 return (error); 2200 2201 mutex_enter(softnet_lock); 2202 KERNEL_LOCK(1, NULL); 2203 2204 ipflow_prune(); 2205 2206 KERNEL_UNLOCK_ONE(NULL); 2207 mutex_exit(softnet_lock); 2208 2209 return (0); 2210 } 2211 2212 static int 2213 sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS) 2214 { 2215 int error, tmp; 2216 struct sysctlnode node; 2217 2218 node = *rnode; 2219 tmp = ip_hashsize; 2220 node.sysctl_data = &tmp; 2221 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2222 if (error || newp == NULL) 2223 return (error); 2224 2225 if ((tmp & (tmp - 1)) == 0 && tmp != 0) { 2226 /* 2227 * Can only fail due to malloc() 2228 */ 2229 mutex_enter(softnet_lock); 2230 KERNEL_LOCK(1, NULL); 2231 2232 error = ipflow_invalidate_all(tmp); 2233 2234 KERNEL_UNLOCK_ONE(NULL); 2235 mutex_exit(softnet_lock); 2236 2237 } else { 2238 /* 2239 * EINVAL if not a power of 2 2240 */ 2241 error = EINVAL; 2242 } 2243 2244 return error; 2245 } 2246 #endif /* GATEWAY */ 2247 2248 static int 2249 sysctl_net_inet_ip_stats(SYSCTLFN_ARGS) 2250 { 2251 2252 return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS)); 2253 } 2254 2255 static void 2256 sysctl_net_inet_ip_setup(struct sysctllog **clog) 2257 { 2258 extern int subnetsarelocal, hostzeroisbroadcast; 2259 2260 sysctl_createv(clog, 0, NULL, NULL, 2261 CTLFLAG_PERMANENT, 2262 CTLTYPE_NODE, "net", NULL, 2263 NULL, 0, NULL, 0, 2264 CTL_NET, CTL_EOL); 2265 sysctl_createv(clog, 0, NULL, NULL, 2266 CTLFLAG_PERMANENT, 2267 CTLTYPE_NODE, "inet", 2268 SYSCTL_DESCR("PF_INET related settings"), 2269 NULL, 0, NULL, 0, 2270 CTL_NET, PF_INET, CTL_EOL); 2271 sysctl_createv(clog, 0, NULL, NULL, 2272 CTLFLAG_PERMANENT, 2273 CTLTYPE_NODE, "ip", 2274 SYSCTL_DESCR("IPv4 related settings"), 2275 NULL, 0, NULL, 0, 2276 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL); 2277 2278 sysctl_createv(clog, 0, NULL, NULL, 2279 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2280 CTLTYPE_INT, "forwarding", 2281 SYSCTL_DESCR("Enable forwarding of INET datagrams"), 2282 NULL, 0, &ipforwarding, 0, 2283 CTL_NET, PF_INET, IPPROTO_IP, 2284 IPCTL_FORWARDING, CTL_EOL); 2285 sysctl_createv(clog, 0, NULL, NULL, 2286 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2287 CTLTYPE_INT, "redirect", 2288 SYSCTL_DESCR("Enable sending of ICMP redirect messages"), 2289 NULL, 0, &ipsendredirects, 0, 2290 CTL_NET, PF_INET, IPPROTO_IP, 2291 IPCTL_SENDREDIRECTS, CTL_EOL); 2292 sysctl_createv(clog, 0, NULL, NULL, 2293 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2294 CTLTYPE_INT, "ttl", 2295 SYSCTL_DESCR("Default TTL for an INET datagram"), 2296 NULL, 0, &ip_defttl, 0, 2297 CTL_NET, PF_INET, IPPROTO_IP, 2298 IPCTL_DEFTTL, CTL_EOL); 2299 #ifdef IPCTL_DEFMTU 2300 sysctl_createv(clog, 0, NULL, NULL, 2301 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */, 2302 CTLTYPE_INT, "mtu", 2303 SYSCTL_DESCR("Default MTA for an INET route"), 2304 NULL, 0, &ip_mtu, 0, 2305 CTL_NET, PF_INET, IPPROTO_IP, 2306 IPCTL_DEFMTU, CTL_EOL); 2307 #endif /* IPCTL_DEFMTU */ 2308 sysctl_createv(clog, 0, NULL, NULL, 2309 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2310 CTLTYPE_INT, "forwsrcrt", 2311 SYSCTL_DESCR("Enable forwarding of source-routed " 2312 "datagrams"), 2313 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0, 2314 CTL_NET, PF_INET, IPPROTO_IP, 2315 IPCTL_FORWSRCRT, CTL_EOL); 2316 sysctl_createv(clog, 0, NULL, NULL, 2317 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2318 CTLTYPE_INT, "directed-broadcast", 2319 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"), 2320 NULL, 0, &ip_directedbcast, 0, 2321 CTL_NET, PF_INET, IPPROTO_IP, 2322 IPCTL_DIRECTEDBCAST, CTL_EOL); 2323 sysctl_createv(clog, 0, NULL, NULL, 2324 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2325 CTLTYPE_INT, "allowsrcrt", 2326 SYSCTL_DESCR("Accept source-routed datagrams"), 2327 NULL, 0, &ip_allowsrcrt, 0, 2328 CTL_NET, PF_INET, IPPROTO_IP, 2329 IPCTL_ALLOWSRCRT, CTL_EOL); 2330 sysctl_createv(clog, 0, NULL, NULL, 2331 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2332 CTLTYPE_INT, "subnetsarelocal", 2333 SYSCTL_DESCR("Whether logical subnets are considered " 2334 "local"), 2335 NULL, 0, &subnetsarelocal, 0, 2336 CTL_NET, PF_INET, IPPROTO_IP, 2337 IPCTL_SUBNETSARELOCAL, CTL_EOL); 2338 sysctl_createv(clog, 0, NULL, NULL, 2339 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2340 CTLTYPE_INT, "mtudisc", 2341 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"), 2342 NULL, 0, &ip_mtudisc, 0, 2343 CTL_NET, PF_INET, IPPROTO_IP, 2344 IPCTL_MTUDISC, CTL_EOL); 2345 sysctl_createv(clog, 0, NULL, NULL, 2346 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2347 CTLTYPE_INT, "anonportmin", 2348 SYSCTL_DESCR("Lowest ephemeral port number to assign"), 2349 sysctl_net_inet_ip_ports, 0, &anonportmin, 0, 2350 CTL_NET, PF_INET, IPPROTO_IP, 2351 IPCTL_ANONPORTMIN, CTL_EOL); 2352 sysctl_createv(clog, 0, NULL, NULL, 2353 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2354 CTLTYPE_INT, "anonportmax", 2355 SYSCTL_DESCR("Highest ephemeral port number to assign"), 2356 sysctl_net_inet_ip_ports, 0, &anonportmax, 0, 2357 CTL_NET, PF_INET, IPPROTO_IP, 2358 IPCTL_ANONPORTMAX, CTL_EOL); 2359 sysctl_createv(clog, 0, NULL, NULL, 2360 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2361 CTLTYPE_INT, "mtudisctimeout", 2362 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"), 2363 sysctl_net_inet_ip_pmtudto, 0, &ip_mtudisc_timeout, 0, 2364 CTL_NET, PF_INET, IPPROTO_IP, 2365 IPCTL_MTUDISCTIMEOUT, CTL_EOL); 2366 #ifdef GATEWAY 2367 sysctl_createv(clog, 0, NULL, NULL, 2368 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2369 CTLTYPE_INT, "maxflows", 2370 SYSCTL_DESCR("Number of flows for fast forwarding"), 2371 sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0, 2372 CTL_NET, PF_INET, IPPROTO_IP, 2373 IPCTL_MAXFLOWS, CTL_EOL); 2374 sysctl_createv(clog, 0, NULL, NULL, 2375 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2376 CTLTYPE_INT, "hashsize", 2377 SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"), 2378 sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0, 2379 CTL_NET, PF_INET, IPPROTO_IP, 2380 CTL_CREATE, CTL_EOL); 2381 #endif /* GATEWAY */ 2382 sysctl_createv(clog, 0, NULL, NULL, 2383 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2384 CTLTYPE_INT, "hostzerobroadcast", 2385 SYSCTL_DESCR("All zeroes address is broadcast address"), 2386 NULL, 0, &hostzeroisbroadcast, 0, 2387 CTL_NET, PF_INET, IPPROTO_IP, 2388 IPCTL_HOSTZEROBROADCAST, CTL_EOL); 2389 #if NGIF > 0 2390 sysctl_createv(clog, 0, NULL, NULL, 2391 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2392 CTLTYPE_INT, "gifttl", 2393 SYSCTL_DESCR("Default TTL for a gif tunnel datagram"), 2394 NULL, 0, &ip_gif_ttl, 0, 2395 CTL_NET, PF_INET, IPPROTO_IP, 2396 IPCTL_GIF_TTL, CTL_EOL); 2397 #endif /* NGIF */ 2398 #ifndef IPNOPRIVPORTS 2399 sysctl_createv(clog, 0, NULL, NULL, 2400 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2401 CTLTYPE_INT, "lowportmin", 2402 SYSCTL_DESCR("Lowest privileged ephemeral port number " 2403 "to assign"), 2404 sysctl_net_inet_ip_ports, 0, &lowportmin, 0, 2405 CTL_NET, PF_INET, IPPROTO_IP, 2406 IPCTL_LOWPORTMIN, CTL_EOL); 2407 sysctl_createv(clog, 0, NULL, NULL, 2408 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2409 CTLTYPE_INT, "lowportmax", 2410 SYSCTL_DESCR("Highest privileged ephemeral port number " 2411 "to assign"), 2412 sysctl_net_inet_ip_ports, 0, &lowportmax, 0, 2413 CTL_NET, PF_INET, IPPROTO_IP, 2414 IPCTL_LOWPORTMAX, CTL_EOL); 2415 #endif /* IPNOPRIVPORTS */ 2416 sysctl_createv(clog, 0, NULL, NULL, 2417 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2418 CTLTYPE_INT, "maxfragpackets", 2419 SYSCTL_DESCR("Maximum number of fragments to retain for " 2420 "possible reassembly"), 2421 NULL, 0, &ip_maxfragpackets, 0, 2422 CTL_NET, PF_INET, IPPROTO_IP, 2423 IPCTL_MAXFRAGPACKETS, CTL_EOL); 2424 #if NGRE > 0 2425 sysctl_createv(clog, 0, NULL, NULL, 2426 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2427 CTLTYPE_INT, "grettl", 2428 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"), 2429 NULL, 0, &ip_gre_ttl, 0, 2430 CTL_NET, PF_INET, IPPROTO_IP, 2431 IPCTL_GRE_TTL, CTL_EOL); 2432 #endif /* NGRE */ 2433 sysctl_createv(clog, 0, NULL, NULL, 2434 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2435 CTLTYPE_INT, "checkinterface", 2436 SYSCTL_DESCR("Enable receive side of Strong ES model " 2437 "from RFC1122"), 2438 NULL, 0, &ip_checkinterface, 0, 2439 CTL_NET, PF_INET, IPPROTO_IP, 2440 IPCTL_CHECKINTERFACE, CTL_EOL); 2441 sysctl_createv(clog, 0, NULL, NULL, 2442 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2443 CTLTYPE_INT, "random_id", 2444 SYSCTL_DESCR("Assign random ip_id values"), 2445 NULL, 0, &ip_do_randomid, 0, 2446 CTL_NET, PF_INET, IPPROTO_IP, 2447 IPCTL_RANDOMID, CTL_EOL); 2448 sysctl_createv(clog, 0, NULL, NULL, 2449 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2450 CTLTYPE_INT, "do_loopback_cksum", 2451 SYSCTL_DESCR("Perform IP checksum on loopback"), 2452 NULL, 0, &ip_do_loopback_cksum, 0, 2453 CTL_NET, PF_INET, IPPROTO_IP, 2454 IPCTL_LOOPBACKCKSUM, CTL_EOL); 2455 sysctl_createv(clog, 0, NULL, NULL, 2456 CTLFLAG_PERMANENT, 2457 CTLTYPE_STRUCT, "stats", 2458 SYSCTL_DESCR("IP statistics"), 2459 sysctl_net_inet_ip_stats, 0, NULL, 0, 2460 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS, 2461 CTL_EOL); 2462 } 2463 2464 void 2465 ip_statinc(u_int stat) 2466 { 2467 2468 KASSERT(stat < IP_NSTATS); 2469 IP_STATINC(stat); 2470 } 2471